FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Tigelaar, DA Waldecker, JR Peplowski, KM Kinder, JD AF Tigelaar, Dean A. Waldecker, James R. Peplowski, Katherine M. Kinder, James D. TI Study of the incorporation of protic ionic liquids into hydrophilic and hydrophobic rigid-rod elastomeric polymers SO POLYMER LA English DT Article DE proton exchange membrane; poly(pyridinium triflate)s; melamine ID RANDOM STATISTICAL COPOLYMERS; TEMPERATURE FUEL-CELLS; CONDUCTING MEMBRANES; EXCHANGE MEMBRANES; ELECTROLYTE MEMBRANES; DIRECT POLYMERIZATION; CONVERGENT SYNTHESES; PEMFC SCIENCE; QUANTUM JUMPS; ACID AB A series of polymers was synthesized that contain a rigid aromatic backbone connected through triazine linkages that are cross-linked by flexible diamine-terminated poly(ethylene oxide) oligomers. Polymers were made that contained both hydrophilic sulfonated aromatic and hydrophobic pyridinium triflate backbones. Thermal and mechanical properties of the resulting polymer films were studied, as well as uptake of water and protic ionic liquids. Ionic liquid uptake varied from 41 to 440%, depending upon the nature of the polymer. The ionic liquid-doped films were analyzed for proton conductivity at high temperatures (> 150 degrees C) under non-humidified conditions. Conductivities as high as 5 X 10(-2) S/cm were observed at 150 degrees C. (c) 2006 Published by Elsevier Ltd. C1 NASA, Glenn Res Ctr, Mat Branch, Cleveland, OH 44135 USA. RP Tigelaar, DA (reprint author), NASA, Glenn Res Ctr, Mat Branch, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM dean.m.tigelaar@grc.nasa.gov NR 38 TC 27 Z9 28 U1 4 U2 24 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY 31 PY 2006 VL 47 IS 12 BP 4269 EP 4275 DI 10.1016/j.polymer.2006.04.014 PG 7 WC Polymer Science SC Polymer Science GA 060UM UT WOS:000238827100004 ER PT J AU Notomi, Y Srinath, G Shiota, T Martin-Miklovic, MG Beachler, L Howell, K Oryszak, SJ Deserranno, DG Freed, AD Greenberg, NL Younoszai, A Thomas, JD AF Notomi, Yuichi Srinath, Gowdagere Shiota, Takahiro Martin-Miklovic, Maureen G. Beachler, Lisa Howell, Kelly Oryszak, Stephanie J. Deserranno, Dimitri G. Freed, Alan D. Greenberg, Neil L. Younoszai, Adel Thomas, James D. TI Maturational and adaptive modulation of left ventricular torsional biomechanics - Doppler tissue imaging observation from infancy to adulthood SO CIRCULATION LA English DT Article DE aging; cardiac development; echocardiography; left ventricular function; pediatrics ID HUMAN-HEART; AORTIC-STENOSIS; RELAXATION; AGE; CONTRACTILITY; AFTERLOAD; CHILDREN; GROWTH; MRI; DEFORMATION AB Background - Left ventricular (LV) torsional deformation, based in part on the helical myocardial fiber architecture, is an important component of LV systolic and diastolic performance. However, there is no comprehensive study describing its normal development during childhood and adult life. Methods and Results - Forty-five normal subjects (25 children and 20 adults; aged 9 days to 49 years; divided into 5 groups: infants, children, adolescents, and young and middle-age adults) underwent assessment of LV torsion and untwisting rate by Doppler tissue imaging. LV torsion increased with age, primarily owing to augmentation in basal clockwise rotation during childhood and apical counterclockwise rotation during adulthood. Although LV torsion and untwisting overall showed age-related increases, when normalized by LV length, they showed higher values in infancy and middle age. The proportion of untwisting during isovolumic relaxation was lowest in infancy, increased during childhood, and leveled off thereafter, whereas peak untwisting performance (peak untwisting velocity normalized by peak LV torsion) showed a decrease during adulthood. Conclusions - We have shown the maturational process of LV torsion in normal subjects. Net LV torsion increases gradually from infancy to adulthood, but the determinants of this were different in the 2 age groups. The smaller LV isovolumic untwisting recoil during infancy and its decline in adulthood may suggest mechanisms for alterations in diastolic function. C1 Cleveland Clin Fdn, Dept Cardiovasc Med F15, Cleveland, OH 44195 USA. Cleveland Clin Fdn, Dept Pediat, Cleveland, OH 44195 USA. NASA, Glenn Res Ctr, Cleveland, OH USA. RP Thomas, JD (reprint author), Cleveland Clin Fdn, Dept Cardiovasc Med F15, 9500 Euclid Ave, Cleveland, OH 44195 USA. EM thomasj@ccf.org OI Freed, Alan/0000-0002-3492-0628 FU NCRR NIH HHS [M01 RR-018390] NR 39 TC 86 Z9 111 U1 0 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD MAY 30 PY 2006 VL 113 IS 21 BP 2534 EP 2541 DI 10.1161/CIRCULATIONHA.105.537639 PG 8 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 048RQ UT WOS:000237964600013 PM 16717154 ER PT J AU Hyde, P Dubayah, R Walker, W Blair, JB Hofton, M Hunsaker, C AF Hyde, P Dubayah, R Walker, W Blair, JB Hofton, M Hunsaker, C TI Mapping forest structure for wildlife habitat analysis using multi-sensor (LiDAR, SAR/InSAR, ETM plus , Quickbird) synergy SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE LiDAR; RaDAR; SAR; InSAR; fusion; habitat; forest structure; canopy height; biomass ID AIRBORNE LASER DATA; CANOPY STRUCTURE; RAIN-FOREST; VEGETATION; BIOMASS; INTEGRATION; TOPOGRAPHY; ALTIMETER; INVENTORY; HEIGHT AB Measurements of forest structure are important for wildlife habitat management. An optimal strategy for mapping forest structure would include detailed measurements of the vertical dimension, which are traditionally provided by field sampling, together with the broad spatial coverage afforded by remote sensing. While no single sensor is capable of delivering this at the present time, it should be possible to combine information from multiple sensors to achieve a reasonable approximation. In this study, we compare estimates of forest structural metrics derived from remote sensing to measurements obtained in the field (large tree maximum canopy height, mean canopy height, standard deviation canopy height, and biomass). We then statistically combine structural information from LiDAR, RaDAR, and passive optical sensors in an attempt to improve accuracy of our estimates. The results of this study indicate that LiDAR is the best single sensor for estimating canopy height and biomass. The addition of ETM+ metrics significantly improved LiDAR estimates of large tree structure, while Quickbird and InSAR/SAR improved estimates either marginally or not at all. The combination of all sensors was more accurate than LiDAR alone, but only marginally better than the combination of LiDAR and ETM+. Structure metrics from LiDAR and RaDAR are essentially redundant, as are ETM+ and Quickbird. (c) 2006 Elsevier Inc. All rights reserved. C1 Univ Maryland, Dept Geog, College Pk, MD 20742 USA. Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. NASAs Goddard Space Flight Ctr, Lab Terr Phys, Greenbelt, MD 20771 USA. US Forest Serv, Dept Agr, Fresno, CA 93729 USA. RP Hyde, P (reprint author), Univ Maryland, Dept Geog, College Pk, MD 20742 USA. EM phyde@geog.umd.edu RI Blair, James/D-3881-2013; Beckley, Matthew/D-4547-2013 NR 27 TC 180 Z9 186 U1 8 U2 93 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 30 PY 2006 VL 102 IS 1-2 BP 63 EP 73 DI 10.1016/j.rse.2006.01.021 PG 11 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 045WD UT WOS:000237772500006 ER PT J AU Textor, C Schulz, M Guibert, S Kinne, S Balkanski, Y Bauer, S Berntsen, T Berglen, T Boucher, O Chin, M Dentener, F Diehl, T Easter, R Feichter, H Fillmore, D Ghan, S Ginoux, P Gong, S Kristjansson, JE Krol, M Lauer, A Lamarque, JF Liu, X Montanaro, V Myhre, G Penner, J Pitari, G Reddy, S Seland, O Stier, P Takemura, T Tie, X AF Textor, C. Schulz, M. Guibert, S. Kinne, S. Balkanski, Y. Bauer, S. Berntsen, T. Berglen, T. Boucher, O. Chin, M. Dentener, F. Diehl, T. Easter, R. Feichter, H. Fillmore, D. Ghan, S. Ginoux, P. Gong, S. Kristjansson, J. E. Krol, M. Lauer, A. Lamarque, J. F. Liu, X. Montanaro, V. Myhre, G. Penner, J. Pitari, G. Reddy, S. Seland, O. Stier, P. Takemura, T. Tie, X. TI Analysis and quantification of the diversities of aerosol life cycles within AeroCom SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Review ID GENERAL-CIRCULATION MODEL; GLOBAL 3-DIMENSIONAL MODEL; CHEMICAL-TRANSPORT MODEL; SEA-SALT AEROSOL; DRY DEPOSITION PARAMETERIZATION; SIZE-SEGREGATED SIMULATION; TROPOSPHERIC SULFUR CYCLE; COMMUNITY CLIMATE MODEL; AIR-QUALITY MODELS; LARGE-SCALE MODELS AB Simulation results of global aerosol models have been assembled in the framework of the AeroCom intercomparison exercise. In this paper, we analyze the life cycles of dust, sea salt, sulfate, black carbon and particulate organic matter as simulated by sixteen global aerosol models. The differences among the results (model diversities) for sources and sinks, burdens, particle sizes, water uptakes, and spatial dispersals have been established. These diversities have large consequences for the calculated radiative forcing and the aerosol concentrations at the surface. Processes and parameters are identified which deserve further research. The AeroCom all-models-average emissions are dominated by the mass of sea salt (SS), followed by dust (DU), sulfate (SO4), particulate organic matter (POM), and finally black carbon (BC). Interactive parameterizations of the emissions and contrasting particles sizes of SS and DU lead generally to higher diversities of these species, and for total aerosol. The lower diversity of the emissions of the fine aerosols, BC, POM, and SO4, is due to the use of similar emission inventories, and does therefore not necessarily indicate a better understanding of their sources. The diversity of SO4-sources is mainly caused by the disagreement on depositional loss of precursor gases and on chemical production. The diversities of the emissions are passed on to the burdens, but the latter are also strongly affected by the model-specific treatments of transport and aerosol processes. The burdens of dry masses decrease from largest to smallest: DU, SS, SO4, POM, and BC. The all-models-average residence time is shortest for SS with about half a day, followed by SO4 and DU with four days, and POM and BC with six and seven days, respectively. The wet deposition rate is controlled by the solubility and increases from DU, BC, POM to SO4 and SS. It is the dominant sink for SO4, BC, and POM, and contributes about one third to the total removal of SS and DU species. For SS and DU we find high diversities for the removal rate coefficients and deposition pathways. Models do neither agree on the split between wet and dry deposition, nor on that between sedimentation and other dry deposition processes. We diagnose an extremely high diversity for the uptake of ambient water vapor that influences the particle size and thus the sink rate coefficients. Furthermore, we find little agreement among the model results for the partitioning of wet removal into scavenging by convective and stratiform rain. Large differences exist for aerosol dispersal both in the vertical and in the horizontal direction. In some models, a minimum of total aerosol concentration is simulated at the surface. Aerosol dispersal is most pronounced for SO4 and BC and lowest for SS. Diversities are higher for meridional than for vertical dispersal, they are similar for the individual species and highest for SS and DU. For these two components we do not find a correlation between vertical and meridional aerosol dispersal. In addition the degree of dispersals of SS and DU is not related to their residence times. SO4, BC, and POM, however, show increased meridional dispersal in models with larger vertical dispersal, and dispersal is larger for longer simulated residence times. C1 Lab Sci Climat & Environm, Gif Sur Yvette, France. Max Planck Inst Meteorol, Hamburg, Germany. Columbia Univ, GISS, New York, NY 10027 USA. Univ Oslo, Dept Geophys, Oslo, Norway. Univ Sci & Technol Lille, CNRS, Opt Atmospher Lab, Villeneuve Dascq, France. EC, Joint Res Ctr, Inst Environm & Sustainabil, Climate Change Unit, Ispra, Italy. NCAR, Boulder, CO USA. Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ USA. ARQM Meteorol Serv Canda, Toronto, ON, Canada. DLR Oberpfaffenhofen, Inst Phys Atmosphare, Oberpfaffenhofen, Germany. Univ Utrecht, Inst Marine & Atmospher Res Utrecht, Utrecht, Netherlands. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Aquila, I-67100 Laquila, Italy. Kyushu Univ, Fukuoka 812, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Met Off, Hadley Ctr, Exeter, Devon, England. RP Textor, C (reprint author), Lab Sci Climat & Environm, Gif Sur Yvette, France. EM christiane.textor@cea.fr RI Lamarque, Jean-Francois/L-2313-2014; Bauer, Susanne/P-3082-2014; Schulz, Michael/A-6930-2011; U-ID, Kyushu/C-5291-2016; Ghan, Steven/H-4301-2011; Kyushu, RIAM/F-4018-2015; Myhre, Gunnar/A-3598-2008; Stier, Philip/B-2258-2008; Krol, Maarten/B-3597-2010; Takemura, Toshihiko/C-2822-2009; Ginoux, Paul/C-2326-2008; Boucher, Olivier/J-5810-2012; Chin, Mian/J-8354-2012; Boucher, Olivier/K-7483-2012; Penner, Joyce/J-1719-2012; Krol, Maarten/E-3414-2013; Liu, Xiaohong/E-9304-2011; Balkanski, Yves/A-6616-2011 OI Lamarque, Jean-Francois/0000-0002-4225-5074; Schulz, Michael/0000-0003-4493-4158; Ghan, Steven/0000-0001-8355-8699; Pitari, Giovanni/0000-0001-7051-9578; Myhre, Gunnar/0000-0002-4309-476X; Stier, Philip/0000-0002-1191-0128; Takemura, Toshihiko/0000-0002-2859-6067; Ginoux, Paul/0000-0003-3642-2988; Boucher, Olivier/0000-0003-2328-5769; Boucher, Olivier/0000-0003-2328-5769; Liu, Xiaohong/0000-0002-3994-5955; Balkanski, Yves/0000-0001-8241-2858 NR 208 TC 524 Z9 530 U1 15 U2 116 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 EI 1680-7324 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD MAY 29 PY 2006 VL 6 BP 1777 EP 1813 PG 37 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046XY UT WOS:000237845600002 ER PT J AU Kinne, S Schulz, M Textor, C Guibert, S Balkanski, Y Bauer, SE Berntsen, T Berglen, TF Boucher, O Chin, M Collins, W Dentener, F Diehl, T Easter, R Feichter, J Fillmore, D Ghan, S Ginoux, P Gong, S Grini, A Hendricks, JE Herzog, M Horowitz, L Isaksen, I Iversen, T Kirkavag, A Kloster, S Koch, D Kristjansson, JE Krol, M Lauer, A Lamarque, JF Lesins, G Liu, X Lohmann, U Montanaro, V Myhre, G Penner, JE Pitari, G Reddy, S Seland, O Stier, P Takemura, T Tie, X AF Kinne, S. Schulz, M. Textor, C. Guibert, S. Balkanski, Y. Bauer, S. E. Berntsen, T. Berglen, T. F. Boucher, O. Chin, M. Collins, W. Dentener, F. Diehl, T. Easter, R. Feichter, J. Fillmore, D. Ghan, S. Ginoux, P. Gong, S. Grini, A. Hendricks, J.E. Herzog, M. Horowitz, L. Isaksen, I. Iversen, T. Kirkavag, A. Kloster, S. Koch, D. Kristjansson, J. E. Krol, M. Lauer, A. Lamarque, J. F. Lesins, G. Liu, X. Lohmann, U. Montanaro, V. Myhre, G. Penner, J. E. Pitari, G. Reddy, S. Seland, O. Stier, P. Takemura, T. Tie, X. TI An AeroCom initial assessment - optical properties in aerosol component modules of global models SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID OCEAN; AERONET; DEPTH; RETRIEVALS; PERIOD; LAND AB The AeroCom exercise diagnoses multicomponent aerosol modules in global modeling. In an initial assessment simulated global distributions for mass and mid-visible aerosol optical thickness (aot) were compared among 20 different modules. Model diversity was also explored in the context of previous comparisons. For the component combined aot general agreement has improved for the annual global mean. At 0.11 to 0.14, simulated aot values are at the lower end of global averages suggested by remote sensing from ground (AERONET ca. 0.135) and space ( satellite composite ca. 0.15). More detailed comparisons, however, reveal that larger differences in regional distribution and significant differences in compositional mixture remain. Of particular concern are large model diversities for contributions by dust and carbonaceous aerosol, because they lead to significant uncertainty in aerosol absorption (aab). Since aot and aab, both, influence the aerosol impact on the radiative energy-balance, the aerosol (direct) forcing uncertainty in modeling is larger than differences in aot might suggest. New diagnostic approaches are proposed to trace model differences in terms of aerosol processing and transport: These include the prescription of common input (e.g. amount, size and injection of aerosol component emissions) and the use of observational capabilities from ground (e.g. measurements networks) or space (e.g. correlations between aerosol and clouds). C1 Max Planck Inst Meteorol, Hamburg, Germany. Lab Sci Climat & Environm, Gif Sur Yvette, France. Columbia Univ, Earth Inst, New York, NY USA. Univ Oslo, Dept Geosci, Oslo, Norway. USTL, CNRS, Opt Atmospher Lab, Villeneuve Dascq, France. Met Off, Hadley Ctr, Exeter, Devon, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NCAR, Boulder, CO USA. EC, Joint Res Ctr, IES, Climate Change Unit, Ispra, Italy. UMBC, Goddard Earth Sci & Technol Ctr, Baltimore, MD USA. Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ USA. ARQM Mateorol Serv Canada, Toronto, ON, Canada. DLR, Inst Phys Atmosphare, Oberpfaffenhofen, Germany. Univ Michigan, Ann Arbor, MI 48109 USA. Inst Marine & Atmospher Res Utrecht, Utrecht, Netherlands. Dalhousie Univ, Halifax, NS, Canada. ETH, Zurich, Switzerland. Univ Aquila, I-67100 Laquila, Italy. Kyushu Univ, Fukuoka 812, Japan. RP Kinne, S (reprint author), Max Planck Inst Meteorol, Hamburg, Germany. EM stefan.kinne@zmaw.de RI Balkanski, Yves/A-6616-2011; Collins, William/J-3147-2014; Lamarque, Jean-Francois/L-2313-2014; Bauer, Susanne/P-3082-2014; Lohmann, Ulrike/B-6153-2009; Schulz, Michael/A-6930-2011; U-ID, Kyushu/C-5291-2016; Ghan, Steven/H-4301-2011; Kyushu, RIAM/F-4018-2015; Myhre, Gunnar/A-3598-2008; Stier, Philip/B-2258-2008; Liu, Xiaohong/E-9304-2011; Krol, Maarten/B-3597-2010; Herzog, Michael/B-4722-2010; Takemura, Toshihiko/C-2822-2009; Ginoux, Paul/C-2326-2008; Boucher, Olivier/J-5810-2012; Chin, Mian/J-8354-2012; Boucher, Olivier/K-7483-2012; Penner, Joyce/J-1719-2012; Krol, Maarten/E-3414-2013; Horowitz, Larry/D-8048-2014 OI Balkanski, Yves/0000-0001-8241-2858; Collins, William/0000-0002-4463-9848; Lamarque, Jean-Francois/0000-0002-4225-5074; Lohmann, Ulrike/0000-0001-8885-3785; Schulz, Michael/0000-0003-4493-4158; Ghan, Steven/0000-0001-8355-8699; Pitari, Giovanni/0000-0001-7051-9578; Myhre, Gunnar/0000-0002-4309-476X; Stier, Philip/0000-0002-1191-0128; Liu, Xiaohong/0000-0002-3994-5955; Takemura, Toshihiko/0000-0002-2859-6067; Ginoux, Paul/0000-0003-3642-2988; Boucher, Olivier/0000-0003-2328-5769; Boucher, Olivier/0000-0003-2328-5769; Horowitz, Larry/0000-0002-5886-3314 NR 18 TC 354 Z9 359 U1 5 U2 39 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD MAY 29 PY 2006 VL 6 BP 1815 EP 1834 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046XY UT WOS:000237845600003 ER PT J AU Swartz, WH Yee, JH Randall, CE Shetter, RE Browell, EV Burris, JF Mcgee, TJ Avery, MA AF Swartz, WH Yee, JH Randall, CE Shetter, RE Browell, EV Burris, JF Mcgee, TJ Avery, MA TI Comparison of high-latitude line-of-sight ozone column density with derived ozone fields and the effects of horizontal inhomogeneity SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID AIRBORNE SUN PHOTOMETER; SOLVE-II; POAM-III; POLAR VORTEX; RETRIEVAL; SATELLITE; RECONSTRUCTION; LIDAR; VALIDATION; MODEL AB Extensive ozone measurements were made during the second SAGE III Ozone Loss and Validation Experiment (SOLVE II). We compare high-latitude line-of-sight (LOS) slant column ozone measurements from the NASA DC-8 to ozone simulated by forward integration of measurement-derived ozone fields constructed both with and without the assumption of horizontal homogeneity. The average bias and rms error of the simulations assuming homogeneity are relatively small (-6 and 10%, respectively) in comparison to the LOS measurements. The comparison improves significantly (-2% bias; 8% rms error) using forward integrations of three-dimensional proxy ozone fields reconstructed from potential vorticity-O-3 correlations. The comparisons provide additional verification of the proxy fields and quantify the influence of large-scale ozone inhomogeneity. The spatial inhomogeneity of the atmosphere is a source of error in the retrieval of trace gas vertical profiles and column abundance from LOS measurements, as well as a complicating factor in intercomparisons that include LOS measurements at large solar zenith angles. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Swartz, WH (reprint author), Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. EM bill.swartz@jhuapl.edu RI Swartz, William/A-1965-2010; McGee, Thomas/G-4951-2013; Randall, Cora/L-8760-2014 OI Swartz, William/0000-0002-9172-7189; Randall, Cora/0000-0002-4313-4397 NR 23 TC 4 Z9 4 U1 1 U2 3 PU EUROPEAN GEOSCIENCES UNION PI KATLENBURG-LINDAU PA MAX-PLANCK-STR 13, 37191 KATLENBURG-LINDAU, GERMANY SN 1680-7316 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD MAY 29 PY 2006 VL 6 BP 1843 EP 1852 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046XY UT WOS:000237845600005 ER PT J AU Wang, DY AF Wang, DY TI A full dimensional, nine-degree-of-freedom, time-dependent quantum dynamics study for the H-2+C2H reaction SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RATE CONSTANTS; REDUCED DIMENSIONALITY; SCATTERING; STATE; STEREODYNAMICS; ATMOSPHERE; CHEMISTRY AB A full dimensional, nine-degree-of-freedom (9DOF), time-dependent quantum dynamics wave packet approach is presented for the study of the H-2+C2H -> H+C2H2 reaction system. This is the first full dimensional quantum dynamics study for a diatom-triatom reaction system. The effects of the initial vibrational and rotational excitations of the reactants on the reactivity of this reaction are investigated. This study shows that vibrational excitations of H-2 enhance the reactivity; whereas, the vibrational excitations of C2H only have a small effect on the reaction probability. In addition, the bending excitations of C2H, compared to the ground state reaction probability, hinder the reactivity. Comparison of the ground state reaction probabilities of the 9DOF and 8DOF shows the reaction probability from the full dimensional calculation is larger, with more prominent resonance features. (c) 2006 American Institute of Physics. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Wang, DY (reprint author), Pacific NW Natl Lab, POB 999 MSIN,K8-91, Richland, WA 99352 USA. EM dunyou.wang@pnl.gov NR 34 TC 31 Z9 31 U1 1 U2 14 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 28 PY 2006 VL 124 IS 20 AR 201105 DI 10.1063/1.2206180 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 048JX UT WOS:000237944500005 PM 16774308 ER PT J AU Frieler, K Rex, M Salawitch, RJ Canty, T Streibel, M Stimpfle, RM Pfeilsticker, K Dorf, M Weisenstein, DK Godin-Beekmann, S AF Frieler, K. Rex, M. Salawitch, R. J. Canty, T. Streibel, M. Stimpfle, R. M. Pfeilsticker, K. Dorf, M. Weisenstein, D. K. Godin-Beekmann, S. TI Toward a better quantitative understanding of polar stratospheric ozone loss SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID DEPLETION; VORTEX; MODEL; CLO AB Previous studies have shown that observed large O-3 loss rates in cold Arctic Januaries cannot be explained with current understanding of the loss processes, recommended reaction kinetics, and standard assumptions about total stratospheric chlorine and bromine. Studies based on data collected during recent field campaigns suggest faster rates of photolysis and thermal decomposition of ClOOCl and higher stratospheric bromine concentrations than previously assumed. We show that a model accounting for these kinetic changes and higher levels of BrO can largely resolve the January Arctic O-3 loss problem and closely reproduces observed Arctic O-3 loss while being consistent with observed levels of ClO and ClOOCl. The model also suggests that bromine catalysed O-3 loss is more important relative to chlorine catalysed loss than previously thought. C1 Alfred Wegener Inst Polar & Marine Res, Res Dept, D-14401 Potsdam, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Cambridge, Dept Chem, European Ozone Res Coordinating Unit, Cambridge CB2 1EW, England. Harvard Univ, Dept Chem & Biol Chem, Cambridge, MA 02138 USA. Heidelberg Univ, Inst Umweltphys, D-69120 Heidelberg, Germany. Atmospher & Environm Res Inc, Lexington, MA 02421 USA. Univ Paris 06, CNRS, Serv Aeron, F-75252 Paris 05, France. RP Frieler, K (reprint author), Alfred Wegener Inst Polar & Marine Res, Res Dept, D-14401 Potsdam, Germany. EM kfrieler@awi-potsdam.de RI Rex, Markus/A-6054-2009; Salawitch, Ross/B-4605-2009; Canty, Timothy/F-2631-2010; OI Rex, Markus/0000-0001-7847-8221; Salawitch, Ross/0000-0001-8597-5832; Canty, Timothy/0000-0003-0618-056X; Frieler, Katja/0000-0003-4869-3013 NR 19 TC 43 Z9 43 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 27 PY 2006 VL 33 IS 10 AR L10812 DI 10.1029/2005GL025466 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 049TB UT WOS:000238038700002 ER PT J AU Thomas, R Frederick, E Krabill, W Manizade, S Martin, C AF Thomas, R Frederick, E Krabill, W Manizade, S Martin, C TI Progressive increase in ice loss from Greenland SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MASS-BALANCE; ELEVATION CHANGES; EAST GREENLAND; OUTLET GLACIER; SHEET; ALTIMETRY; SURFACE; GRACE AB Laser altimeter measurements over Greenland show increasing thickening rates above 2000 m, reflecting increasing snowfall in a warming climate. But near-coastal thinning rates have increased substantially since the mid 1990s, and net mass loss more than doubled from an average of 4 - 50 Gt yr(-1) between 1993/4 and 1998/9 to 57 - 105 Gt yr(-1) between 1998/9 and 2004. This increasing trend is very similar to findings from independent mass-budget studies, but differs widely from ERS radar altimeter results. This may result from limitations associated with the large ERS footprint over sloping and undulating surfaces that typify fast, narrow glaciers where thinning is most pronounced. C1 NASA, Goddard Space Flight Ctr, WFF, EG&G, Wallops Isl, VA 23337 USA. RP Thomas, R (reprint author), NASA, Goddard Space Flight Ctr, WFF, EG&G, Bldg N-159, Wallops Isl, VA 23337 USA. EM thomas@osb.wff.nasa.gov NR 19 TC 87 Z9 87 U1 2 U2 29 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 27 PY 2006 VL 33 IS 10 AR L10503 DI 10.1029/2006GL026075 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 049TB UT WOS:000238038700007 ER PT J AU Suess, ST Nerney, S AF Suess, ST Nerney, S TI Flow speed inside the brightness boundary of coronal streamers SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOLAR MINIMUM; STAGNATION FLOW; WIND; TEMPERATURE; OUTFLOW; REGION; MODEL; IONS AB Density measurements in the legs of coronal streamers, where there might be outflow, are reproduced here using a magnetohydrodynamic model of the flow inside the brightness boundary of streamers. The model returns values for the flow speed and stream tube geometry (spreading) between the base and a few solar radii. The flow speed is consistent with there being no measurable outflow below 2.5 R. and an outflow of similar to 100 km/s at 5 R.. We briefly describe the model, observations, and physical interpretation. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Ohio Univ, Dept Phys, Lancaster, OH 43130 USA. RP Suess, ST (reprint author), NASA, George C Marshall Space Flight Ctr, Mail Code VP62, Huntsville, AL 35812 USA. EM steven.t.suess@nasa.gov; nerney@ohiou.edu NR 22 TC 7 Z9 7 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 26 PY 2006 VL 33 IS 10 AR L10104 DI 10.1029/2006GL026182 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 049TA UT WOS:000238038500007 ER PT J AU Richardson, IG Webb, DF Zhang, J Berdichevsky, DB Biesecker, DA Kasper, JC Kataoka, R Steinberg, JT Thompson, BJ Wu, CC Zhukov, AN AF Richardson, IG Webb, DF Zhang, J Berdichevsky, DB Biesecker, DA Kasper, JC Kataoka, R Steinberg, JT Thompson, BJ Wu, CC Zhukov, AN TI Major geomagnetic storms (Dst <=-100 nT) generated by corotating interaction regions SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; INTERPLANETARY MAGNETIC-FIELD; HELIOSPHERIC PLASMA SHEET; WIND STREAM INTERFACES; SOLAR-WIND; SEMIANNUAL VARIATION; ALFVEN WAVES; ELECTRONS; IDENTIFICATION; DISTURBANCES AB [ 1] Seventy-nine major geomagnetic storms ( minimum Dst <= - 100 nT) observed in 1996 to 2004 were the focus of a "Living with a Star'' Coordinated Data Analysis Workshop ( CDAW) in March 2005. In nine cases, the storm driver appears to have been purely a corotating interaction region (CIR) without any contribution from coronal mass ejection-related material ( interplanetary coronal mass ejections (ICMEs)). These storms were generated by structures within CIRs located both before and/or after the stream interface that included persistently southward magnetic fields for intervals of several hours. We compare their geomagnetic effects with those of 159 CIRs observed during 1996 - 2005. The major storms form the extreme tail of a continuous distribution of CIR geoeffectiveness which peaks at Dst similar to - 40 nT but is subject to a prominent seasonal variation of similar to 40 nT which is ordered by the spring and fall equinoxes and the solar wind magnetic field direction toward or away from the Sun. The O'Brien and McPherron ( 2000) equations, which estimate Dst by integrating the incident solar wind electric field and incorporating a ring current loss term, largely account for the variation in storm size. They tend to underestimate the size of the larger CIR-associated storms by Dst similar to 20 nT. This suggests that injection into the ring current may be more efficient than expected in such storms. Four of the nine major storms in 1996 - 2004 occurred during a period of less than three solar rotations in September to November 2002, also the time of maximum mean IMF and solar magnetic field intensity during the current solar cycle. The maximum CIR-storm strength found in our sample of events, plus additional 23 probable CIR-associated Dst <= - 100 nT storms in 1972 - 1995, is ( Dst = - 161 nT). This is consistent with the maximum storm strength ( Dst similar to - 180 nT) expected from the O'Brien and McPherron equations for the typical range of solar wind electric fields associated with CIRs. This suggests that CIRs alone are unlikely to generate geomagnetic storms that exceed these levels. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. L3 Govt Serv Inc, Chantilly, VA USA. NOAA, Space Environm Ctr, Boulder, CO 80305 USA. MIT, Space Res Ctr, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL USA. Royal Observ Belgium, B-1180 Brussels, Belgium. Moscow MV Lomonosov State Univ, Skobeltsyn Inst Nucl Phys, Moscow, Russia. RP Richardson, IG (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM richardson@lheavx.gsfc.nasa.gov; david.webb.ctr@hanscom.af.mil; jierz@scs.gmu.edu; dberdich@pop600.gsfc.nasa.gov; doug.biesecker@noaa.gov; jck@mit.edu; ryuho@nict.go.jp; jsteinberg@lanl.gov; barbara.j.thompson@nasa.gov; wuc@cspar.uah.edu; andrei.zhukov@oma.be RI Kasper, Justin/D-1152-2010; Thompson, Barbara/C-9429-2012; OI Kasper, Justin/0000-0002-7077-930X; Richardson, Ian/0000-0002-3855-3634 NR 49 TC 74 Z9 74 U1 1 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 26 PY 2006 VL 111 IS A7 AR A07S09 DI 10.1029/2005JA011476 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 049VS UT WOS:000238046300001 ER PT J AU Acosta, D AF Acosta, D TI Working together for communication SO SCIENCE LA English DT Letter C1 NASA, Off Publ Affairs, Washington, DC 20546 USA. RP Acosta, D (reprint author), NASA, Off Publ Affairs, Washington, DC 20546 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAY 26 PY 2006 VL 312 IS 5777 BP 1138 EP 1138 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 048OW UT WOS:000237957400020 PM 16728617 ER PT J AU Chang-Diaz, FR AF Chang-Diaz, FR TI Plasma propulsion for interplanetary flight SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Joint Meeting of the 7th Asia Pacific Conference on Plasma Science and Technology/17th Symposium on Plasma Science for Materials (APCPST/SPSM) CY JUN 29-JUL 02, 2004 CL Fukuoka, JAPAN SP 153rd Comm Plasma Mat Sci DE experimental methods; helicon; plasma propulsion AB The Variable Specific Impulse Magnetoplasma Rocket (VASIMR) is a high-power propulsion concept using radio waves to create and accelerate plasma in a magnetic nozzle. Important features are its high and variable exhaust velocity, which greatly enhances performance. A NASA-led, research team is developing this technology in the U.S. Recent advances include demonstration of efficient propellant utilization in its helicon plasma source and experimental verification of high ion acceleration through ion cyclotron wave resonance absorption, as predicted by theory. This paper describes the physics and engineering of VASIMR, reviews recent progress and discusses its application in a piloted Mars mission architecture. (c) 2005 Published by Elsevier B.V. C1 NASA, Johnson Space Ctr, ASPL, Houston, TX 77059 USA. RP Chang-Diaz, FR (reprint author), NASA, Johnson Space Ctr, ASPL, 13000 Space Ctr Blvd, Houston, TX 77059 USA. EM fcliatlg@ems.jsc.nasa.gov NR 7 TC 9 Z9 9 U1 0 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD MAY 26 PY 2006 VL 506 BP 449 EP 453 DI 10.1016/j.tsf.2005.08.324 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 034ME UT WOS:000236932300097 ER PT J AU Squire, JP Chang-Diaz, FR Glover, TW Jacobson, VT McCaskill, GE Winter, DS Baity, FW Carter, MD Goulding, RH AF Squire, JP Chang-Diaz, FR Glover, TW Jacobson, VT McCaskill, GE Winter, DS Baity, FW Carter, MD Goulding, RH TI High power light gas helicon plasma source for VASIMR SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Joint Meeting of the 7th Asia Pacific Conference on Plasma Science and Technology/17th Symposium on Plasma Science for Materials (APCPST/SPSM) CY JUN 29-JUL 02, 2004 CL Fukuoka, JAPAN SP 153rd Comm Plasma Mat Sci DE experimental methods; helicon; plasma propulsion AB In the Advanced Space Propulsion Laboratory (ASPL) helicon experiment (VX-10) we have measured a plasma flux to input gas rate ratio near 100% for both helium and deuterium at power levels up to 10 M Recent results at Oak Ridge National Laboratory (ORNL) show enhanced efficiency operation with a high power density, over 5 kW in a 5 cm diameter tube. Our helicon is presently 9 cm in diameter and operates up to 10 kW of input power. The data here uses a Boswell double-saddle antenna design with a magnetic cusp just upstream of the antenna. Similar to ORNL, for deuterium at near 10 M, we find an enhanced performance of operation at magnetic fields above the lower hybrid matching condition. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, ASPL, Houston, TX 77059 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Squire, JP (reprint author), NASA, Lyndon B Johnson Space Ctr, ASPL, 13000 Space Ctr Blvd, Houston, TX 77059 USA. RI Goulding, Richard/C-5982-2016 OI Goulding, Richard/0000-0002-1776-7983 NR 9 TC 14 Z9 14 U1 1 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD MAY 26 PY 2006 VL 506 BP 579 EP 582 DI 10.1016/j.tsf.2005.08.061 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 034ME UT WOS:000236932300124 ER PT J AU Benna, M Mahaffy, PR AF Benna, M Mahaffy, PR TI New multi-fluid MHD model of comet 26P/Grigg-Skjellerup: Extrapolation to comet 67P/Churyumov-Gerasimenko SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID P-GRIGG-SKJELLERUP; SOLAR-WIND; ENCOUNTER; HALLEY; GIOTTO AB The Multi-fluid MHD simulator CASIM3D models the atmosphere of comet 26P/Grigg-Skjellerup as it was seen by the Giotto spacecraft during its flyby of the comet in July 1992. CASIM3D integrates the major chemical reactions and physical interactions to compute self-consistently over an adaptive Cartesian mesh the dynamics of ions, electrons, and neutrals within the coma. Using this model, we derived water ion velocity and density profiles and magnetic field strength along the Giotto path that are in good agreement with the recorded observations. This model is also extrapolated to the case of 67P/Churyumov-Gerasimenko for its perihelion passage of 2015 to provide a preliminary assessment of the structure of the coma of this comet. We show that the inner boundary layers are just few dozen kilometers large. This could provide an additional constraint to the orbit of the spacecraft Rosetta to maximize the science return of the mission. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Benna, M (reprint author), NASA, Goddard Space Flight Ctr, Code 699, Greenbelt, MD 20771 USA. EM mehdi.benna@gsfc.nasa.gov RI Mahaffy, Paul/E-4609-2012; Benna, Mehdi/F-3489-2012 NR 18 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 25 PY 2006 VL 33 IS 10 AR L10103 DI 10.1029/2006GL026197 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 049SY UT WOS:000238038300004 ER PT J AU Fruchter, AS Levan, AJ Strolger, L Vreeswijk, PM Thorsett, SE Bersier, D Burud, I Ceron, JMC Castro-Tirado, AJ Conselice, C Dahlen, T Ferguson, HC Fynbo, JPU Garnavich, PM Gibbons, RA Gorosabel, J Gull, TR Hjorth, J Holland, ST Kouveliotou, C Levay, Z Livio, M Metzger, MR Nugent, PE Petro, L Pian, E Rhoads, JE Riess, AG Sahu, KC Smette, A Tanvir, NR Wijers, RAMJ Woosley, SE AF Fruchter, A. S. Levan, A. J. Strolger, L. Vreeswijk, P. M. Thorsett, S. E. Bersier, D. Burud, I. Castro Ceron, J. M. Castro-Tirado, A. J. Conselice, C. Dahlen, T. Ferguson, H. C. Fynbo, J. P. U. Garnavich, P. M. Gibbons, R. A. Gorosabel, J. Gull, T. R. Hjorth, J. Holland, S. T. Kouveliotou, C. Levay, Z. Livio, M. Metzger, M. R. Nugent, P. E. Petro, L. Pian, E. Rhoads, J. E. Riess, A. G. Sahu, K. C. Smette, A. Tanvir, N. R. Wijers, R. A. M. J. Woosley, S. E. TI Long gamma-ray bursts and core-collapse supernovae have different environments SO NATURE LA English DT Article ID HOST GALAXIES; LOW METALLICITY; MASSIVE STARS; IA SUPERNOVAE; REDSHIFT; AFTERGLOW; PROGENITORS; RATES; SPECTROSCOPY; CONSTRAINTS AB When massive stars exhaust their fuel, they collapse and often produce the extraordinarily bright explosions known as core-collapse supernovae. On occasion, this stellar collapse also powers an even more brilliant relativistic explosion known as a long-duration gamma-ray burst. One would then expect that these long gamma-ray bursts and core-collapse supernovae should be found in similar galactic environments. Here we show that this expectation is wrong. We find that the gamma-ray bursts are far more concentrated in the very brightest regions of their host galaxies than are the core-collapse supernovae. Furthermore, the host galaxies of the long gamma-ray bursts are significantly fainter and more irregular than the hosts of the core-collapse supernovae. Together these results suggest that long-duration gamma-ray bursts are associated with the most extremely massive stars and may be restricted to galaxies of limited chemical evolution. Our results directly imply that long gamma-ray bursts are relatively rare in galaxies such as our own Milky Way. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. Western Kentucky Univ, Bowling Green, KY 42101 USA. European So Observ, Santiago 19, Chile. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England. Norwegian Meteorol Inst, N-0313 Oslo, Norway. Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen, Denmark. CSIC, Inst Astrofis Andalucia, E-18008 Granada, Spain. CALTECH, Pasadena, CA 91125 USA. Univ Nottingham, Sch Phys & Astron, Nottingham NG7 2RD, England. Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Extraterr Planets & Stellar Astrophys Explorat Un, Greenbelt, MD 20771 USA. NASA, George C Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA. Renaissance Technol Corp, E Setauket, NY 11733 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Osserv Astron Trieste, INAF, I-34131 Trieste, Italy. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. RP Fruchter, AS (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. EM fruchter@stsci.edu RI Gull, Theodore/D-2753-2012; Conselice, Christopher/B-4348-2013; Fynbo, Johan/L-8496-2014; Hjorth, Jens/M-5787-2014; OI Gull, Theodore/0000-0002-6851-5380; Fynbo, Johan/0000-0002-8149-8298; Hjorth, Jens/0000-0002-4571-2306; Thorsett, Stephen/0000-0002-2025-9613; Castro-Tirado, A. J./0000-0003-2999-3563; Petro, Larry/0000-0001-8879-528X; Wijers, Ralph/0000-0002-3101-1808 NR 50 TC 472 Z9 475 U1 1 U2 13 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 25 PY 2006 VL 441 IS 7092 BP 463 EP 468 DI 10.1038/nature04787 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 045YP UT WOS:000237778900040 PM 16688183 ER PT J AU Cuzzi, JN Alexander, CMO AF Cuzzi, JN Alexander, CMO TI Chondrule formation in particle-rich nebular regions at least hundreds of kilometres across SO NATURE LA English DT Article ID SOLAR NEBULA; ISOTOPIC FRACTIONATION; PROTOPLANETARY DISK; EVOLUTION; MODEL; CONSTRAINTS; ORIGIN; SHOCKS AB Chondrules are millimetre-sized spherules (mostly silicate) that dominate the texture of primitive meteorites(1). Their formation mechanism is debated, but their sheer abundance suggests that the mechanism was both energetic and ubiquitous in the early inner Solar System(2). The processes suggested-such as shock waves, solar flares or nebula lightning(3-7)-operate on different length scales that have been hard to relate directly to chondrule properties. Chondrules are depleted in volatile elements, but surprisingly they show little evidence for the associated loss of lighter isotopes one would expect(8). Here we report a model in which molten chondrules come to equilibrium with the gas that was evaporated from other chondrules, and which explains the observations in a natural way. The regions within which the chondrules formed must have been larger than 150-6,000 km in radius, and must have had a precursor number density of at least 10 m(-3). These constraints probably exclude nebula lightning, and also make formation far from the nebula midplane problematic. The wide range of chondrule compositions may be the result of different combinations of the local concentrations of precursors and the local abundance of water ice or vapour. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. RP Cuzzi, JN (reprint author), NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM jcuzzi@mail.arc.nasa.gov RI Alexander, Conel/N-7533-2013 OI Alexander, Conel/0000-0002-8558-1427 NR 27 TC 79 Z9 79 U1 0 U2 4 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 25 PY 2006 VL 441 IS 7092 BP 483 EP 485 DI 10.1038/nature04834 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 045YP UT WOS:000237778900043 PM 16724060 ER PT J AU Yamasoe, MA von Randow, C Manzi, AO Schafer, JS Eck, TF Holben, BN AF Yamasoe, MA von Randow, C Manzi, AO Schafer, JS Eck, TF Holben, BN TI Effect of smoke and clouds on the transmissivity of photosynthetically active radiation inside the canopy SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID BIOMASS-BURNING AEROSOLS; OPTICAL-PROPERTIES; GLOBAL RADIATION; DIRECT COMPONENT; AMAZON SMOKE; RAIN-FOREST; CARBON; SCATTERING; DIFFUSE; ALBEDO AB Biomass burning activities emit high concentrations of aerosol particles to the atmosphere. Such particles can interact with solar radiation, decreasing the amount of light reaching the surface and increasing the fraction of diffuse radiation through scattering processes, and thus has implications for photosynthesis within plant canopies. This work reports results from photosynthetically active radiation ( PAR) and aerosol optical depth (AOD) measurements conducted simultaneously at Reserva Biologica do Jaru (Rondonia State, Brazil) during LBA/SMOCC (Large-Scale Biosphere-Atmosphere Experiment in Amazonia/Smoke, Aerosols, Clouds, Rainfall, and Climate) and RaCCI ( Radiation, Cloud, and Climate Interactions in the Amazon during the Dry-to-Wet Transition Season) field experiments from 15 September to 15 November 2002. AOD values were retrieved from an AERONET ( Aerosol Robotic Network) radiometer, MODIS ( Moderate Resolution Spectroradiometer) and a portable sunphotometer from the United States Department of Agriculture - Forest Service. Significant reduction of PAR irradiance at the top of the canopy was observed due to the smoke aerosol particles layer. This radiation reduction affected turbulent fluxes of sensible and latent heats. The increase of AOD also enhanced the transmission of PAR inside the canopy. As a consequence, the availability of diffuse radiation was enhanced due to light scattering by the aerosol particles. A complex relationship was identified between light availability inside the canopy and net ecosystem exchange ( NEE). The results showed that the increase of aerosol optical depth corresponded to an increase of CO2 uptake by the vegetation. However, for even higher AOD values, the corresponding NEE was lower than for intermediate values. As expected, water vapor pressure deficit (VPD), retrieved at 28 m height inside the canopy, can also affect photosynthesis. A decrease in NEE was observed as VPD increased. Further studies are needed to better understand these findings, which were reported for the first time for the Amazon region under smoky conditions. C1 Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo, Brazil. Univ Wageningen & Res Ctr, Alterra, NL-6700 AA Wageningen, Netherlands. Inst Nacl de Pesquisas da Amazonia, BR-69060001 Manaus, Amazonas, Brazil. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP Yamasoe, MA (reprint author), Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Rua Matao 1226, BR-05508090 Sao Paulo, Brazil. EM akemi@model.iag.usp.br RI von Randow, Celso/B-3335-2009; Schafer, Joel/A-3978-2010; ECK, THOMAS/D-7407-2012; Yamasoe, Marcia/L-3667-2013 OI von Randow, Celso/0000-0003-1045-4316; Yamasoe, Marcia/0000-0003-3066-9146 NR 35 TC 18 Z9 22 U1 0 U2 14 PU EUROPEAN GEOSCIENCES UNION PI KATLENBURG-LINDAU PA MAX-PLANCK-STR 13, 37191 KATLENBURG-LINDAU, GERMANY SN 1680-7316 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD MAY 22 PY 2006 VL 6 BP 1645 EP 1656 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 044TS UT WOS:000237695900002 ER PT J AU Bates, TS Anderson, TL Baynard, T Bond, T Boucher, O Carmichael, G Clarke, A Erlick, C Guo, H Horowitz, L Howell, S Kulkarni, S Maring, H McComiskey, A Middlebrook, A Noone, K O'Dowd, CD Ogren, J Penner, J Quinn, PK Ravishankara, AR Savoie, DL Schwartz, SE Shinozuka, Y Tang, Y Weber, RJ Wu, Y AF Bates, T. S. Anderson, T. L. Baynard, T. Bond, T. Boucher, O. Carmichael, G. Clarke, A. Erlick, C. Guo, H. Horowitz, L. Howell, S. Kulkarni, S. Maring, H. McComiskey, A. Middlebrook, A. Noone, K. O'Dowd, C. D. Ogren, J. Penner, J. Quinn, P. K. Ravishankara, A. R. Savoie, D. L. Schwartz, S. E. Shinozuka, Y. Tang, Y. Weber, R. J. Wu, Y. TI Aerosol direct radiative effects over the northwest Atlantic, northwest Pacific, and North Indian Oceans: estimates based on in-situ chemical and optical measurements and chemical transport modeling SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Review ID EXPERIMENT ACE 1; TRACE-P EXPERIMENT; ANTHROPOGENIC SULFATE AEROSOLS; LOWER TROPOSPHERIC AEROSOL; GREENSTEIN PHASE FUNCTION; SINGLE SCATTERING ALBEDO; MARINE BOUNDARY-LAYER; LONG-RANGE TRANSPORT; SEA-SALT AEROSOLS; CARBONACEOUS AEROSOLS AB The largest uncertainty in the radiative forcing of climate change over the industrial era is that due to aerosols, a substantial fraction of which is the uncertainty associated with scattering and absorption of shortwave ( solar) radiation by anthropogenic aerosols in cloud-free conditions (IPCC, 2001). Quantifying and reducing the uncertainty in aerosol influences on climate is critical to understanding climate change over the industrial period and to improving predictions of future climate change for assumed emission scenarios. Measurements of aerosol properties during major field campaigns in several regions of the globe during the past decade are contributing to an enhanced understanding of atmospheric aerosols and their effects on light scattering and climate. The present study, which focuses on three regions downwind of major urban/population centers ( North Indian Ocean (NIO) during INDOEX, the Northwest Pacific Ocean (NWP) during ACE-Asia, and the Northwest Atlantic Ocean (NWA) during ICARTT), incorporates understanding gained from field observations of aerosol distributions and properties into calculations of perturbations in radiative fluxes due to these aerosols. This study evaluates the current state of observations and of two chemical transport models ( STEM and MOZART). Measurements of burdens, extinction optical depth (AOD), and direct radiative effect of aerosols (DRE - change in radiative flux due to total aerosols) are used as measurement-model check points to assess uncertainties. In-situ measured and remotely sensed aerosol properties for each region ( mixing state, mass scattering efficiency, single scattering albedo, and angular scattering properties and their dependences on relative humidity) are used as input parameters to two radiative transfer models (GFDL and University of Michigan) to constrain estimates of aerosol radiative effects, with uncertainties in each step propagated through the analysis. Constraining the radiative transfer calculations by observational inputs increases the clear-sky, 24-h averaged AOD ( 34 +/- 8%), top of atmosphere (TOA) DRE ( 32 +/- 12%), and TOA direct climate forcing of aerosols (DCF - change in radiative flux due to anthropogenic aerosols) ( 37 +/- 7%) relative to values obtained with "a priori" parameterizations of aerosol loadings and properties (GFDL RTM). The resulting constrained clear-sky TOA DCF is - 3.3 +/- 0.47, - 14 +/- 2.6, - 6.4 +/- 2.1W m(-2) for the NIO, NWP, and NWA, respectively. With the use of constrained quantities ( extensive and intensive parameters) the calculated uncertainty in DCF was 25% less than the "structural uncertainties" used in the IPCC-2001 global estimates of direct aerosol climate forcing. Such comparisons with observations and resultant reductions in uncertainties are essential for improving and developing confidence in climate model calculations incorporating aerosol forcing. C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. NOAA, Earth Syst Res Lab, Boulder, CO USA. Univ Illinois, Dept Civil & Environm Engn, Urbana, IL 61801 USA. Met Off, Climate Chem & Ecosyst Team, Exeter, Devon, England. Univ Iowa, Ctr Global & Reg Environm Res, Iowa City, IA USA. Univ Hawaii, Dept Oceanog, Honolulu, HI 96822 USA. Hebrew Univ Jerusalem, Dept Atmospher Sci, Jerusalem, Israel. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ USA. NASA Headquarters, Radiat Sci Program, Washington, DC USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Int Geosphere Biosphere Program, Stockholm, Sweden. Natl Univ Ireland, Dept Expt Phys, Galway, Ireland. Natl Univ Ireland, Environm Change Inst, Galway, Ireland. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. RP Bates, TS (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way NE, Seattle, WA 98115 USA. EM tim.bates@noaa.gov RI Quinn, Patricia/R-1493-2016; Manager, CSD Publications/B-2789-2015; Middlebrook, Ann/E-4831-2011; Boucher, Olivier/J-5810-2012; Penner, Joyce/J-1719-2012; Guo, Huan/D-8282-2014; Horowitz, Larry/D-8048-2014; O'Dowd , Colin/K-8904-2012; Tang, Youhua/D-5205-2016; Bates, Timothy/L-6080-2016; Boucher, Olivier/K-7483-2012; Bond, Tami/A-1317-2013; Schwartz, Stephen/C-2729-2008; McComiskey, Allison/I-3933-2013; Ravishankara, Akkihebbal/A-2914-2011 OI Quinn, Patricia/0000-0003-0337-4895; Middlebrook, Ann/0000-0002-2984-6304; Boucher, Olivier/0000-0003-2328-5769; Horowitz, Larry/0000-0002-5886-3314; O'Dowd , Colin/0000-0002-3068-2212; Tang, Youhua/0000-0001-7089-7915; Boucher, Olivier/0000-0003-2328-5769; Bond, Tami/0000-0001-5968-8928; Schwartz, Stephen/0000-0001-6288-310X; McComiskey, Allison/0000-0002-6125-742X; NR 243 TC 92 Z9 95 U1 3 U2 38 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 EI 1680-7324 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD MAY 22 PY 2006 VL 6 BP 1657 EP 1732 DI 10.5194/acp-6-1657-2006 PG 76 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 044TS UT WOS:000237695900003 ER PT J AU Hurkett, CP Osborne, JP Page, KL Rol, E Goad, MR O'Brien, PT Beardmore, A Godet, O Burrows, DN Tanvir, NR Levan, A Zhang, B Malesani, D Hill, JE Kennea, JA Chapman, R La Parola, V Perri, M Romano, P Smith, R Gehrels, N AF Hurkett, CP Osborne, JP Page, KL Rol, E Goad, MR O'Brien, PT Beardmore, A Godet, O Burrows, DN Tanvir, NR Levan, A Zhang, B Malesani, D Hill, JE Kennea, JA Chapman, R La Parola, V Perri, M Romano, P Smith, R Gehrels, N TI GRB 050505: a high-redshift burst discovered by Swift SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : high-redshift; galaxies : ISM; gamma-rays : bursts; gamma-rays : observations ID GAMMA-RAY BURST; STRUCTURED OUTFLOWS; ENERGY INJECTION; LIGHT-CURVE; AFTERGLOWS; JETS; DUST; TELESCOPE; SPECTRA; ENVIRONMENT AB We report the discovery and subsequent multiwavelength afterglow behaviour of the high-redshift (z = 4.27) Gamma Ray Burst (GRB) 050505. This burst is the third most-distant burst, measured by spectroscopic redshift, discovered after GRB 000131 (z = 4.50) and GRB ;050904 (z = 6.29). GRB 050505 is a long GRB with a multipeaked gamma-ray light curve, with a duration of T-90 = 63 +/- 2 s and an inferred isotropic release in gamma-rays of similar to 4.44 x 1053 erg in the 1-10(4) keV rest-frame energy range. The Swift X-Ray Telescope followed the afterglow for 14 d, detecting two breaks in the light curve at 7.4(-1.5)(+1.5) and 58.0(-15.4)(+9.9) ks after the burst trigger. The power-law decay slopes before, between and after these breaks were 0.25(-0.17)(+0.16), 1.17(-0.09)(+0.08) and 1.97(-0.28)(+0.27), respectively. The light curve can also be fitted with a 'smoothly broken' power- law model with a break observed at similar to T + 18.5 ks, with decay slopes of similar to 0.4 and similar to 1.8, before and after the break, respectively. The X-ray afterglow shows no spectral variation over the course of the Swift observations, being well fitted with a single power law of photon index similar to 1.90. This behaviour is expected for the cessation of the continued energization of the interstellar medium shock, followed by a break caused by a jet, either uniform or structured. Neither break is consistent with a cooling break. The spectral energy distribution, indeed, shows the cooling frequency to be below the X-ray but above the optical frequencies. The optical-X-ray spectrum also shows that there is significant X-ray absorption in excess of that due to our Galaxy but very little optical-ultraviolet extinction, with E( B - V) approximate to 0.10 for a Small Magellanic Cloud like extinction curve. C1 Univ Leicester, Dept Phys & Astron, Xray & Observ Grp, Leicester LE1 7RH, Leics, England. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. SISSA, ISAS, I-34014 Trieste, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Ist Astrofis Spaziale & Fis Csom, INAF, Sez Palermo, I-90146 Palermo, Italy. ASI Sci Data Ctr, I-00044 Frascati, Italy. Osserv Astron Brera, INAF, I-23807 Merate, Italy. Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England. RP Hurkett, CP (reprint author), Univ Leicester, Dept Phys & Astron, Xray & Observ Grp, Leicester LE1 7RH, Leics, England. EM cph9@star.le.ac.uk RI Gehrels, Neil/D-2971-2012; OI Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488 NR 71 TC 15 Z9 15 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 21 PY 2006 VL 368 IS 3 BP 1101 EP 1109 DI 10.1111/j.1365-2966.2006.10188.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 040BC UT WOS:000237353000011 ER PT J AU Heymans, C Van Waerbeke, L Bacon, D Berge, J Bernstein, G Bertin, E Bridle, S Brown, ML Clowe, D Dahle, H Erben, T Gray, M Hetterscheidt, M Hoekstra, H Hudelot, P Jarvis, M Kuijken, K Margoniner, V Massey, R Mellier, Y Nakajima, R Refregier, A Rhodes, J Schrabback, T Wittman, D AF Heymans, C Van Waerbeke, L Bacon, D Berge, J Bernstein, G Bertin, E Bridle, S Brown, ML Clowe, D Dahle, H Erben, T Gray, M Hetterscheidt, M Hoekstra, H Hudelot, P Jarvis, M Kuijken, K Margoniner, V Massey, R Mellier, Y Nakajima, R Refregier, A Rhodes, J Schrabback, T Wittman, D TI The Shear Testing Programme - I. Weak lensing analysis of simulated ground-based observations SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE gravitational lensing; cosmology : observations; large-scale structure of Universe ID LARGE-SCALE STRUCTURE; INTRINSIC GALAXY ALIGNMENTS; CLUSTER SURVEY FIELDS; DIGITAL SKY SURVEY; COSMIC SHEAR; DARK-MATTER; GRAVITATIONAL SHEAR; SYSTEMATIC-ERRORS; SPIRAL GALAXIES; TELESCOPE AB The Shear Testing Programme (STEP) is a collaborative project to improve the accuracy and reliability of all weak lensing measurements in preparation for the next generation of wide-field surveys. In this first STEP paper, we present the results of a blind analysis of simulated ground-based observations of relatively simple galaxy morphologies. The most successful methods are shown to achieve percent level accuracy. From the cosmic shear pipelines that have been used to constrain cosmology, we find weak lensing shear measured to an accuracy that is within the statistical errors of current weak lensing analyses, with shear measurements accurate to better than 7 per cent. The dominant source of measurement error is shown to arise from calibration uncertainties where the measured shear is over or underestimated by a constant multiplicative factor. This is of concern as calibration errors cannot be detected through standard diagnostic tests. The measured calibration errors appear to result from stellar contamination, false object detection, the shear measurement method itself, selection bias and/or the use of biased weights. Additive systematics (false detections of shear) resulting from residual point-spread function anisotropy are, in most cases, reduced to below an equivalent shear of 0.001, an order of magnitude below cosmic shear distortions on the scales probed by current surveys. Our results provide a snapshot view of the accuracy of current ground-based weak lensing methods and a benchmark upon which we can improve. To this end we provide descriptions of each method tested and include details of the eight different implementations of the commonly used Kaiser, Squires & Broadhurst method (KSB+) to aid the improvement of future KSB+ analyses. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Univ Edinburgh, Royal Observ, Inst Astron, Edinburgh EH9 3HJ, Midlothian, Scotland. CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Univ Paris 06, CNRS, UMR7095, Inst Astrophys, F-75014 Paris, France. UCL, Dept Phys & Astron, London WC1E 6BT, England. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Oslo, Inst Theoret Astrophys, N-0315 Oslo, Norway. Univ Bonn, Inst Astrophys & Extraterr Forsch, D-53121 Bonn, Germany. Univ Nottingham, Sch Phys & Astron, Nottingham NG7 2RD, England. Univ Victoria, Victoria, BC V8P 5C2, Canada. Observ Midi Pyrenees, UMR5572, F-31000 Toulouse, France. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. CALTECH, Pasadena, CA 91125 USA. Observ Paris, LERMA, F-75014 Paris, France. Jet Prop Lab, Pasadena, CA 91109 USA. RP Heymans, C (reprint author), Max Planck Inst Astron, D-69117 Heidelberg, Germany. EM heymans@physics.ubc.ca OI Gray, Meghan/0000-0002-6301-5870; Wittman, David/0000-0002-0813-5888; Hoekstra, Henk/0000-0002-0641-3231 NR 83 TC 270 Z9 272 U1 1 U2 5 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 21 PY 2006 VL 368 IS 3 BP 1323 EP 1339 DI 10.1111/j.1365-2966.2006.10198.x PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 040BC UT WOS:000237353000028 ER PT J AU Machol, JL Ayers, T Schwenz, KT Koenig, KW Hardesty, RM Senff, CJ Krainak, MA Abshire, JB Bravo, HE Sandberg, SP AF Machol, Janet L. Ayers, Tom Schwenz, Karl T. Koenig, Keith W. Hardesty, R. Michael Senff, Christoph J. Krainak, Michael A. Abshire, James B. Bravo, Hector E. Sandberg, Scott P. TI Preliminary measurements with an automated compact differential absorption lidar for the profiling of water vapor (vol 43, pg 3110, 2004) SO APPLIED OPTICS LA English DT Correction AB In the original paper [Appl. Opt. 43, 3110 (2004)], all occurrences of the Greek letter "mu" were printed as ''m". The corrected expressions are given here. (c) 2006 Optical Society of America C1 Univ Colorado, Cooperat Inst Res Environm Sci, NOAA, ETL, Boulder, CO 80305 USA. Natl Ctr Atmospher Res, Adv Technol Div, Boulder, CO 80307 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Machol, JL (reprint author), Univ Colorado, Cooperat Inst Res Environm Sci, NOAA, ETL, 325 Broadway, Boulder, CO 80305 USA. EM janet.machol@noaa.gov RI Hardesty, Robert/H-9844-2013; Abshire, James/I-2800-2013; Sandberg, Scott/I-4875-2013; Senff, Christoph/I-2592-2013; Machol, Janet/D-5896-2016 OI Machol, Janet/0000-0002-0344-0314 NR 1 TC 3 Z9 3 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAY 20 PY 2006 VL 45 IS 15 BP 3544 EP 3544 DI 10.1364/AO.45.003544 PG 1 WC Optics SC Optics GA 044JM UT WOS:000237668400018 ER PT J AU Lock, JA Wrbanek, SY Weiland, KE AF Lock, James A. Wrbanek, Susan Y. Weiland, Kenneth E. TI Scattering of a tightly focused beam by an optically trapped particle SO APPLIED OPTICS LA English DT Article ID LORENZ-MIE THEORY; AXISYMMETRICAL LASER-BEAM; FAR-FIELD SCATTERING; SPHERICAL-PARTICLE; ELECTROMAGNETIC DIFFRACTION; DIELECTRIC PARTICLES; RADIATION PRESSURE; GAUSSIAN-BEAM; FORCES; AXIS AB Near-forward scattering of an optically trapped 5-mu m-radius polystyrene latex sphere by the trapping beam was examined both theoretically and experimentally. Since the trapping beam is tightly focused, the beam fields superpose and interfere with the scattered fields in the forward hemisphere. The observed light intensity consists of a series of concentric bright and dark fringes centered about the forward-scattering direction. Both the number of fringes and their contrast depend on the position of the trapping beam focal waist with respect to the sphere. The fringes are caused by diffraction that is due to the truncation of the tail of the trapping beam as the beam is transmitted through the sphere. (c) 2006 Optical Society of America C1 Cleveland State Univ, Dept Phys, Cleveland, OH 44115 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Lock, JA (reprint author), Cleveland State Univ, Dept Phys, Cleveland, OH 44115 USA. NR 33 TC 14 Z9 14 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAY 20 PY 2006 VL 45 IS 15 BP 3634 EP 3645 DI 10.1364/AO.45.003634 PG 12 WC Optics SC Optics GA 044JM UT WOS:000237668400028 PM 16708110 ER PT J AU Hornschemeier, AE Mobasher, B Alexander, DM Bauer, FE Bautz, MW Hammer, D Poggianti, BM AF Hornschemeier, AE Mobasher, B Alexander, DM Bauer, FE Bautz, MW Hammer, D Poggianti, BM TI Chandra X-ray observations of galaxies in an off-center region of the Coma Cluster SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; diffuse radiation; surveys; X-rays : galaxies; X-rays : general ID FORMATION RATE INDICATOR; ACTIVE GALACTIC NUCLEI; STAR-FORMING GALAXIES; FIELD NORTH SURVEY; LUMINOSITY FUNCTION; GIANT GALAXIES; DEEP SURVEY; NEARBY GALAXIES; NUMBER COUNTS; POINT SOURCES AB We have performed a pilot Chandra survey of an off-center region of the Coma Cluster to explore the X-ray properties and luminosity function of normal galaxies. We present results on 13 Chandra-detected galaxies with optical photometric matches, including four spectroscopically confirmed Coma-member galaxies. All seven spectroscopically confirmed giant Coma galaxies in this field have detections or limits consistent with low X-ray to optical flux ratios [(f(X)/f(R)) < 10(-3)]. We do not have sufficient numbers of X-ray-detected galaxies to directly measure the galaxy X-ray luminosity function (XLF). However, since we have a well-measured optical LF, we take this low X-ray to optical flux ratio for the seven spectroscopically confirmed galaxies to translate the optical LF to an XLF. We find good agreement with Finoguenov et al. (2004), indicating that the X-ray emission per unit optical flux per galaxy is suppressed in clusters of galaxies, but we extend this work to a specific off-center environment in the Coma Cluster. Finally, we report the discovery of a region of diffuse X-ray flux that might correspond to a small group interacting with the Coma intracluster medium (ICM). C1 NASA, Goddard Space Flight Ctr, Lab XRay Astrophys, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Osserv Astron Padova, I-35122 Padua, Italy. RP Hornschemeier, AE (reprint author), NASA, Goddard Space Flight Ctr, Lab XRay Astrophys, Code 662-0, Greenbelt, MD 20771 USA. OI Alexander, David/0000-0002-5896-6313 NR 40 TC 10 Z9 10 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 144 EP 153 DI 10.1086/500798 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900015 ER PT J AU Norris, JP Bonnell, JT AF Norris, J. P. Bonnell, J. T. TI Short gamma-ray bursts with extended emission SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID BATSE OBSERVATIONS; GRB-050709; AFTERGLOW; ENERGY; DISTRIBUTIONS; DURATION; MISSION; GALAXY AB The recent association of several short gamma-ray bursts ( GRBs) with early-type galaxies with low star formation rates demonstrates that short bursts arise from a different progenitor mechanism than long bursts. However, since the duration distributions of the two classes overlap, membership is not always easily established. The picture is complicated by occasional softer, extended emission lasting tens of seconds after the initial spikelike emission comprising an otherwise short burst. Using the large BATSE sample with time-tagged event ( TTE) data, we show that the fundamental defining characteristic of the short-burst class is that the initial spike exhibits negligible spectral evolution at energies above similar to 25 keV. The behavior is nearly ubiquitous for the 260 bursts with T(90) < 2 s for which the BATSE TTE data type completely included the initial spike. We find this same signature-negligible spectral lag-for six Swift BAT short bursts and one HETE-2 short burst. We also analyze a small sample of "short'' BATSE bursts-those with the most fluent, intense extended emission. The same lack of evolution on the pulse timescale obtains for the extended emission in the brighter bursts for which significant measurements can be made. We also show that the dynamic range in the ratio of peak intensities, spike: extended, is similar to 10(4). However, for our BATSE sample the total counts fluence of the extended component equals or exceeds that in the spike by a factor of several. A high Lorentz factor, similar to 500-1000, might explain the negligible lags. C1 NASA, Goddard Space Flight Ctr, Astroparticle Phys Lab, Greenbelt, MD 20771 USA. RP Norris, JP (reprint author), NASA, Goddard Space Flight Ctr, Astroparticle Phys Lab, Code 661, Greenbelt, MD 20771 USA. NR 42 TC 231 Z9 235 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 266 EP 275 DI 10.1086/502796 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900027 ER PT J AU Schady, P Mason, KO Osborne, JP Page, MJ Roming, PWA Still, M Zhang, B Blustin, AJ Boyd, P Cucchiara, A Gehrels, N Gronwall, C De Pasquale, M Holland, ST Marshall, FE McGowan, KE Nousek, JA AF Schady, P. Mason, K. O. Osborne, J. P. Page, M. J. Roming, P. W. A. Still, M. Zhang, B. Blustin, A. J. Boyd, P. Cucchiara, A. Gehrels, N. Gronwall, C. De Pasquale, M. Holland, S. T. Marshall, F. E. McGowan, K. E. Nousek, J. A. TI Swift UVOT observations of X-ray flash 050406 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; X-rays : individual (XRF 050406) ID GAMMA-RAY-BURSTS; AFTERGLOW LIGHT CURVES; 2-COMPONENT JET; VIEWING ANGLE; FLASHES; EMISSION; ENERGY; TELESCOPE; MODEL; UNIVERSAL AB We present Swift UVOT data on the optical afterglow of the X-ray flash of 2005 April 6 ( XRF 050406) from 88 to similar to 10(5) s after the initial prompt gamma-ray emission. Our observations in the V, B, and U bands are the earliest that have been taken of an XRF optical counterpart. Combining the early-time optical temporal and spectral properties with gamma-ray and simultaneous X-ray data taken with the BAT and XRT telescopes on board Swift, we are able to constrain possible origins of the XRF. The prompt emission had a FRED ( fast-rise, exponential decay) profile with a duration of T(90 =) 5.7 +/- 0.2 s, putting it at the short end of the long-burst duration distribution. The absence of photoelectric absorption redward of 4000 (A) over circle in the UV/optical spectrum provides a firm upper limit of z <= 3.1 on the redshift, thus excluding a high redshift as the sole reason for the soft spectrum. The optical light curve is consistent with a power-law decay with slope alpha = 0.75 +/- 0.26( F(v) proportional to t(alpha)) and a maximum occurring in the first 200 s after the initial gamma-ray emission. The softness of the prompt emission is well described by an off-axis structured jet model, which is able to account for the early peak flux and shallow decay observed in the optical and X- ray bands. C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Particle Phys & Astron Res Council, Swindon SN2 1SZ, Wilts, England. Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. S African Astron Observ, ZA-7935 Cape Town, South Africa. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Schady, P (reprint author), Penn State Univ, Dept Astron & Astrophys, 525 Davey Lab, University Pk, PA 16802 USA. RI Boyd, Patricia/D-3274-2012; Gehrels, Neil/D-2971-2012 NR 73 TC 22 Z9 22 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 276 EP 283 DI 10.1086/501449 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900028 ER PT J AU Bersier, D Fruchter, AS Strolger, LG Gorosabel, J Levan, A Burud, I Rhoads, JE Becker, AC Cassan, A Chornock, R Covino, S De Jong, RS Dominis, D Filippenko, AV Hjorth, J Holmberg, J Malesani, D Mobasher, B Olsen, KAG Stefanon, M Ceron, JMC Fynbo, JPU Holland, ST Kouveliotou, C Pedersen, H Tanvir, NR Woosley, SE AF Bersier, D Fruchter, AS Strolger, LG Gorosabel, J Levan, A Burud, I Rhoads, JE Becker, AC Cassan, A Chornock, R Covino, S De Jong, RS Dominis, D Filippenko, AV Hjorth, J Holmberg, J Malesani, D Mobasher, B Olsen, KAG Stefanon, M Ceron, JMC Fynbo, JPU Holland, ST Kouveliotou, C Pedersen, H Tanvir, NR Woosley, SE TI Evidence for a supernova associated with the X-ray flash 020903 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; supernovae : general ID GAMMA-RAY BURSTS; HUBBLE-SPACE-TELESCOPE; IMAGE SUBTRACTION; OPTICAL AFTERGLOW; UBVRI PHOTOMETRY; LOW-REDSHIFT; GRB 970508; SN 1998BW; FLASHES; LIGHT AB We present ground-based and Hubble Space Telescope optical observations of the X-ray flash ( XRF) 020903, covering 300 days. The afterglow showed a very rapid rise in the first day, followed by a relatively slow decay in the next few days. There was a clear bump in the light curve after similar to 25 days, accompanied by a drastic change in the spectral energy distribution. The light curve and the spectral energy distribution are naturally interpreted as describing the emergence and subsequent decay of a supernova ( SN), similar to SN 1998bw. At peak luminosity, the SN is estimated to be 0.8 +/- 0.1 mag fainter than SN 1998bw. This argues in favor of the existence of a SN associated with this XRF. A spectrum obtained 35 days after the burst shows emission lines from the host galaxy. We use this spectrum to put an upper limit on the oxygen abundance of the host at [O/H] <= 0.6 dex. We also discuss a possible trend between the softness of several bursts and the early behavior of the optical afterglow, in the sense that XRFs and X-ray-rich gamma-ray bursts ( GRBs) seem to have a plateau phase or even a rising light curve. This can be naturally explained in models in which XRFs are similar to GRBs but are seen off the jet axis. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Inst Astrophys, F-75014 Paris, France. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Osserv Astron Brera, INAF, I-23807 Merate, LC, Italy. Univ Potsdam, D-14469 Potsdam, Germany. Astrophys Inst Potsdam, D-14482 Potsdam, Germany. Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen, Denmark. Tuorla Observ, FI-21500 Piikkio, Finland. SISSA, ISAS, I-34014 Trieste, Italy. Cerro Tololo Interamer Observ, Natl Opt Astron Observ, La Serena, Chile. NASA, Goddard Space Flight Ctr, Swift Sci Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. NASA, George C Marshall Space Flight Ctr, NSSTC, Huntsville, AL 35805 USA. Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. RP Bersier, D (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. RI Fynbo, Johan/L-8496-2014; Hjorth, Jens/M-5787-2014; Stefanon, Mauro/F-8708-2016; OI Fynbo, Johan/0000-0002-8149-8298; Hjorth, Jens/0000-0002-4571-2306; Stefanon, Mauro/0000-0001-7768-5309; Covino, Stefano/0000-0001-9078-5507 NR 63 TC 35 Z9 36 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 284 EP 291 DI 10.1086/502640 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900029 ER PT J AU Stothers, RB AF Stothers, RB TI Generalized analytic stellar stability criteria with applications to luminous stellar envelopes SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : mass loss; stars : oscillations; stars : rotation; stars : variables : other; turbulence ID BLUE VARIABLES; RADIATIVE INSTABILITY; STARS; PULSATION; CONVECTION; PRESSURE; MODELS AB Baker's one-zone model of a radiative stellar envelope is generalized here to include additional forces that can be represented as a function of only the stellar radius. The criteria for dynamical, secular, and pulsational stability against radial perturbations are derived and expressed in simple, general analytic forms. Applications are made to the outer envelopes of luminous blue variables ( LBVs). The acceleration of stellar-wind mass loss has no effect on the stability criteria, but axial rotation and slowly adapting convective turbulence produce more complicated effects, depending on whether the envelope is dynamically stable or not. On the other hand, rotation and turbulence are probably very weak in most LBV outer envelopes. C1 NASA, Goddard Space Flight Ctr, Inst Space Studies, New York, NY 10025 USA. RP Stothers, RB (reprint author), NASA, Goddard Space Flight Ctr, Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. NR 25 TC 2 Z9 2 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 423 EP 425 DI 10.1086/501513 PN 1 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900039 ER PT J AU Brown, JC Emslie, AG Holman, GD Johns-Krull, CM Kontar, EP Lin, RP Massone, AM Piana, M AF Brown, JC Emslie, AG Holman, GD Johns-Krull, CM Kontar, EP Lin, RP Massone, AM Piana, M TI Evaluation of algorithms for reconstructing electron spectra from their bremsstrahlung hard X-ray spectra SO ASTROPHYSICAL JOURNAL LA English DT Article DE methods : data analysis; Sun : flares; Sun : X-rays, gamma rays ID 23 SOLAR-FLARE; FLUX SPECTRA; DISTRIBUTIONS; POLARIZATION; INVERSION; BURSTS AB The Ramaty High Energy Solar Spectroscopic Imager (RHESSI) has yielded solar flare hard X-ray spectra with unprecedented resolution, enabling reconstruction of mean source electron energy spectra F(E) by deconvolution of photon energy spectra I(epsilon). While various algorithms have been proposed, the strengths and weaknesses of each have yet to be explored in a systematic fashion. For real data F(E) is unknown, so these various algorithms must instead be tested on simulated data for which the "true'' F(E) is known. Accordingly, we devised several forms of F(E) with "interesting'' features, generated the corresponding (noise-added) I (epsilon), and recovered F(E) using a variety of algorithms, including zero- and first-order Tikhonov regularizations, triangular matrix row elimination, and forward fitting using a parametric form consisting of a double power law with low/high cutoffs plus an isothermal component. All inversion methods reconstructed the general magnitude and form of F(E) well, suffering only from (1) blurring of sharp features and (2) poor recovery at low electron energies E in cases in which F'(E) was positive and large. Addition of a steep thermal component at low E did not prevent recovery of features at higher values of E. Forward fitting did recover large-scale forms and features well but, inevitably, failed to recover local features not expressible within the parametric used. This confirms that inversions are the most dependable way to discover such features. However, examination of the pattern of I(epsilon) residuals can suggest feature locations and so help refine the parametric form used. Since quite smooth F(E) forms do reproduce the observed I(epsilon) form with relatively small residuals, it appears that sharp features may be uncommon in actual flares. C1 Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. CNR, INFM, LAMIA, I-16146 Genoa, Italy. Univ Genoa, Dipartimento Matemat, I-16146 Genoa, Italy. Univ Verona, Dipartimento Informat, I-37134 Verona, Italy. RP Brown, JC (reprint author), Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. EM john@astro.gla.ac.uk; gordon.emslie@okstate.edu; holman@stars.gsfc.nasa.gov; cmj@rice.edu; eduard@astro.gla.ac.uk; boblin@ssl.berkeley.edu; massone@ge.infm.it; piana@dima.unige.it RI Kontar, Eduard/B-7897-2008; Holman, Gordon/C-9548-2012; piana, michele/H-9376-2015; OI Kontar, Eduard/0000-0002-8078-0902; PIANA, MICHELE/0000-0003-1700-991X NR 30 TC 42 Z9 42 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 523 EP 531 DI 10.1086/501497 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900048 ER PT J AU Stansberry, JA Grundy, WM Margot, JL Cruikshank, DP Emery, JP Rieke, GH Trilling, DE AF Stansberry, JA Grundy, WM Margot, JL Cruikshank, DP Emery, JP Rieke, GH Trilling, DE TI The albedo, size, and density of binary Kuiper Belt object (47171) 1999 TC36 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : solar system; Kuiper Belt; solar system : formation ID TRANS-NEPTUNIAN OBJECTS; MULTIBAND IMAGING PHOTOMETER; NEAR-EARTH ASTEROIDS; ESO LARGE PROGRAM; SPACE-TELESCOPE; TRANSNEPTUNIAN OBJECTS; THERMAL-MODEL; SIERRA-NEVADA; SOURCE COUNTS; 1999 TC36 AB We measured the system-integrated thermal emission of the binary Kuiper Belt object (47171) 1999 TC36 at wavelengths near 24 and 70 mu m using the Spitzer Space Telescope. We fit these data and the visual magnitude using both the standard thermal model and thermophysical models. We find that the effective diameter of the binary is 405 km, with a range of 350-470 km, and the effective visible geometric albedo for the system is 0.079, with a range of 0.055-0.11. The binary orbit, magnitude contrast between the components, and system mass have been determined from HST data studied by Margot et al. Our effective diameter, combined with that system mass, indicates an average density for the objects of 0.5 g cm(-3), with a range 0.3-0.8 g cm(-3). This density is low compared to that of materials expected to be abundant in solid bodies in the trans-Neptunian region, requiring 50%-75% of the interior of (47171) 1999 TC36 be taken up by void space. This conclusion is not greatly affected if (47171) 1999 TC36 is "differentiated'' (in the sense of having either a rocky or just a nonporous core). If the primary is itself a binary, the average density of that (hypothetical) triple system would be in the range 0.4-1.1 g cm(-3), with a porosity in the range 15%-70%. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Lowell Observ, Flagstaff, AZ 86001 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. SETI Inst, Mountain View, CA 94043 USA. RP Stansberry, JA (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM stansber@as.arizona.edu RI Margot, Jean-Luc/A-6154-2012 OI Margot, Jean-Luc/0000-0001-9798-1797 NR 78 TC 34 Z9 34 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 556 EP 566 DI 10.1086/502674 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900052 ER PT J AU Remijan, AJ Friedel, DN de Pater, I Hogerheijde, MR Snyder, LE A'Hearn, MF Blake, GA Dickel, HR Forster, JR Kraybill, C Looney, LW Palmer, P Wright, MCH AF Remijan, AJ Friedel, DN de Pater, I Hogerheijde, MR Snyder, LE A'Hearn, MF Blake, GA Dickel, HR Forster, JR Kraybill, C Looney, LW Palmer, P Wright, MCH TI A BIMA array survey of molecules in comets linear (C/2002 T7) and neat (C/2001 Q4) SO ASTROPHYSICAL JOURNAL LA English DT Article DE comets : individual (LINEAR (C/2002 T7), NEAT (C/2001 Q4)); molecular processes; radio lines : solar system; techniques : interferometric ID O1 HALE-BOPP; B2 HYAKUTAKE; C/1995 O1; SUBMILLIMETER; COMA; HCN AB We present an interferometric search for large molecules, including methanol (CH3OH), methyl cyanide (CH3CN), ethyl cyanide (CH3CH2CN), ethanol (CH3CH2OH), and methyl formate (CH3OCHO), in comets LINEAR (C/2002 T7) and NEAT (C/2001 Q4) with the Berkeley-Illinois-Maryland Association (BIMA) array. We also searched for transitions of the simpler molecules CS, SiO, HNC, (HNC)-C-13, and (CO)-C-13. We detected transitions of CH3OH and CS around comet LINEAR and one transition of CH3OH around comet NEAT within a synthesized beam of similar to 20". We calculated the total column density and production rate of each molecular species using the variable temperature and outflow velocity (VTOV) model recently described by Friedel et al. Considering the molecular production rate ratios with respect to water, comet T7 LINEAR is more similar to comet Hale-Bopp, while comet Q4 NEAT is more similar to comet Hyakutake. It is unclear, however, due to such a small sample size, whether there is a clear distinction between a Hale-Bopp and Hyakutake class of comet or whether comets have a continuous range of molecular production rate ratios. C1 NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. CALTECH, Div Chem & Chem Engn, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Remijan, AJ (reprint author), Natl Radio Astron Observ, 520 Edgemont Rd, Charlottesville, VA 22901 USA. EM aremijan@nrao.edu; friedel@astro.uiuc.edu; imke@floris.berkeley.edu; michiel@strw.leidenuniv.nl; snyder@astro.uiuc.edu; ma@astro.umd.edu; gab@gps.caltech.edu; h-dickel@phys.unm.edu; rforster@astro.berkeley.edu; ckraybill@astro.berkeley.edu; lwl@astro.uiuc.edu; wright@astro.berkeley.edu NR 20 TC 19 Z9 19 U1 0 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP 567 EP 572 DI 10.1086/502713 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TP UT WOS:000237624900053 ER PT J AU Apponi, AJ Halfen, DT Ziurys, LM Hollis, JM Remijan, AJ Lovas, FJ AF Apponi, AJ Halfen, DT Ziurys, LM Hollis, JM Remijan, AJ Lovas, FJ TI Investigating the limits of chemical complexity in Sagittarius B2(N): A rigorous attempt to confirm 1,3-dihydroxyacetone SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrobiology; astrochemistry; ISM : abundances; ISM : individual (Sagittarius B2); ISM : molecules ID GLYCOLALDEHYDE; SPECTRUM AB A search for confirming transitions of 1,3-dihydroxyacetone, (CH2OH)(2)CO ( hereafter DHA), has been made toward Sgr B2(N) using the Arizona Radio Observatory Submillimeter Telescope (SMT) and 12 m telescope at millimeter wavelengths. In addition, data for this species have been obtained at the Green Bank Telescope. In all, 63 new transitions of DHA were sought; no plausible emission was detected at 97% of these frequencies. Typical peak-to-peak limits of 10 - 30 mK were achieved, indicating that DHA is not present in Sgr B2( N) at the level reported by Widicus Weaver & Blake in 2005, by at least a factor of 300. The upper limit to the DHA column density is N-tot < 5 x 10(13) cm(-2), suggesting that this species, a three-carbon keto sugar, is less abundant than the two-carbon aldehyde sugar, glycolaldehyde (CH2OHCHO), by a factor of at least 4. If sugars of higher complexity are formed in interstellar clouds, their synthesis may proceed one carbon atom at a time, possibly through aldehyde intermediates. C1 Univ Arizona, Dept Chem, Tucson, AZ 85721 USA. Univ Arizona, Dept Astron, Tucson, AZ 85721 USA. NASA, Computat & Informat Sci & Technol Off, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Radio Astron Observ, Charlottesville, VA 22901 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Apponi, AJ (reprint author), Univ Arizona, Dept Chem, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM aapponi@as.arizona.edu OI Halfen, DeWayne/0000-0003-2483-3616 NR 8 TC 18 Z9 18 U1 0 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP L29 EP L32 DI 10.1086/504979 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TQ UT WOS:000237625000008 ER PT J AU Hollis, JM Lovas, FJ Remijan, AJ Jewell, PR Ilyushin, VV Kleiner, I AF Hollis, JM Lovas, FJ Remijan, AJ Jewell, PR Ilyushin, VV Kleiner, I TI Detection of acetamide (CH3CONH2): The largest interstellar molecule with a peptide bond SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : clouds; ISM : individual (Sagittarius B2(N-LMH)); ISM : molecules; radio lines : ISM ID MICROWAVE-SPECTRUM; TEMPERATURE; FORMAMIDE; ICES AB Acetamide (CH3CONH2) has been detected in emission and absorption toward the star-forming region Sagittarius B2(N) with the 100 m Green Bank Telescope (GBT) by means of four A-species and four E-species rotational transitions. All transitions have energy levels less than 10 K. The Sgr B2( N) cloud is known to have a cold halo with clumps of gas at several different velocities. Absorption features are largely characterized by local standard of rest (LSR) velocities that are typical of the two star-forming cores with systemic LSR velocities of +64 and + 82 km s(-1). Continuum sources embedded within the star-forming cores give rise to the absorption from the molecular gas halo surrounding the cores. Emission features are seen at an approximate intermediate LSR velocity of + 73 km s(-1) that characterizes the widespread molecular halo that has a spatial scale of a few arcminutes. Two low-energy transitions of formamide (HCONH2) were also observed with the GBT toward Sagittarius B2( N) since formamide is the potential parent molecule of acetamide; both molecules are the only interstellar species with an NH2 group bound to a CO group, the so-called peptide bond, that provides the linkage for the polymerization of amino acids. While the acetamide transitions observed appear to be confined to the cold (similar to 8 K) halo region, only the 1(01) - 0(00) transition of formamide appears to be exclusively from the cold halo; the 3(12) - 3(13) transition of formamide is apparently contaminated with emission from the two hot cores. The relative abundance ratio of acetamide to formamide is estimated to be in the range of similar to 0.1 to similar to 0.5 in the cold halo. The exothermic neutral-radical reaction of formamide with methylene (CH2) may account for the synthesis of interstellar acetamide in the presence of shock phenomenon in this star-forming region. C1 NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. Natl Acad Sci Ukraine, Inst Radio Astron, UA-61002 Kharkov, Ukraine. Univ Paris 12, CNRS, LISA, F-94010 Creteil, France. Univ Paris 07, CNRS, LISA, F-94010 Creteil, France. RP Hollis, JM (reprint author), NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Code 606, Greenbelt, MD 20771 USA. NR 16 TC 86 Z9 86 U1 1 U2 15 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP L25 EP L28 DI 10.1086/505110 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TQ UT WOS:000237625000007 ER PT J AU Remijan, AJ Hollis, JM Snyder, LE Jewell, PR Lovas, FJ AF Remijan, AJ Hollis, JM Snyder, LE Jewell, PR Lovas, FJ TI Methyltriacetylene (CH3C6H) toward TMC-1: The largest detected symmetric top SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : clouds; ISM : individual (TMC-1); ISM : molecules; radio lines : ISM ID INTERSTELLAR; METHYLDIACETYLENE; CLOUDS AB We report the detection of a new interstellar methylpolyyne, CH3C6H (methyltriacetylene), with the 100 m Green Bank Telescope. Ten spectral lines of this species were detected toward the Taurus molecular cloud (TMC-1): the K - 0 and K = 1 components of the 12, K - 11, K, 13, K - 12, K, 14, K - 13, K, 15, K - 14, K, and 16, K 15, K transitions. Also observed were the K = 0 and K = 1 components of the 6, K - 5, K transition of CH3C4H (methyldiacetylene). For both methylpolyynes, no higher energy K-components were detected, which is consistent with the 10 K kinetic temperature of the TMC-1 dark cloud. Moreover, radio spectral line data of the cyanopolyyne, methylcyanopolyyne, and methylpolyyne carbon-chain sequences were studied, and strong correlations are found among the values of the three different carbon-chain slopes when total column densities of sequence members are plotted against the number of carbon atoms in the carbon chain. This result suggests that the formation chemistry for all these carbon-chain sequences is common, and the total column density of the next larger, undetected species in each of the three carbon chain sequences is predicted. C1 Natl Radio Astron Observ, Charlottesville, VA 22903 USA. NASA, Computat & Informat Sci & Technol Off, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Remijan, AJ (reprint author), Natl Radio Astron Observ, 520 Edgemont Rd, Charlottesville, VA 22903 USA. NR 19 TC 23 Z9 23 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2006 VL 643 IS 1 BP L37 EP L40 DI 10.1086/504918 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 043TQ UT WOS:000237625000010 ER PT J AU Zhang, MJ Yu, STJ Lin, SCH Chang, SC Blankson, I AF Zhang, MJ Yu, STJ Lin, SCH Chang, SC Blankson, I TI Solving the MHD equations by the space-time conservation element and solution element method SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE MHD; the CESE method; constraint transport ID MULTIDIMENSIONAL IDEAL MAGNETOHYDRODYNAMICS; CONSTRAINED TRANSPORT METHOD; FINITE-DIFFERENCE SCHEME; GODUNOV-TYPE SCHEMES; EULER EQUATIONS; FLOWS AB We apply the space-time conservation element and solution element (CESE) method to solve the ideal MHD equations with special emphasis on satisfying the divergence free constraint of magnetic field.. i.e., del B-. = 0. In the setting of the CESE method, four approaches ire employed: (i) the original CESE method without any additional treatment, (ii) a simple corrector procedure to update the spatial derivatives of magnetic field B after each time marching step to enforce del B-. = 0 at all mesh nodes, (iii) a constraint-transport method by using a special staggered mesh to calculate magnetic field B. and (iv) the projection method by solving a Poisson solver after each time marching step. To demonstrate the capabilities of these methods, two benchmark MHD flows are calculated: (i) a rotated one-dimensional MHD shock tube problem and (ii) a MHD vortex problem. The results show no differences between different approaches and all results compare favorably with previously reported data. (c) 2005 Elsevier Inc. All rights reserved. C1 Ohio State Univ, Dept Mech Engn, Columbus, OH 43202 USA. GM Corp, Warren, MI 48090 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Yu, STJ (reprint author), Ohio State Univ, Dept Mech Engn, 650 Ackerman Rd,Suite 255, Columbus, OH 43202 USA. EM yu.274@osu.edu NR 21 TC 33 Z9 36 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY 20 PY 2006 VL 214 IS 2 BP 599 EP 617 DI 10.1016/j.jcp.2005.10.006 PG 19 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 028WF UT WOS:000236518800009 ER PT J AU Kulikov, I AF Kulikov, I TI Gravitational field measurement with an equilibrium ensemble of cold atoms SO JOURNAL OF MODERN OPTICS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY AB A new approach to the measurement of gravitational fields with an equilibrium ensemble of ultra-cold alkali atoms confined in a cell of volume V is investigated. The proposed model of the gravitational sensor is based on a variation of the density pro. le of the ensemble due to a changing of gravitational field. Measuring the atomic density variations of the ensemble is accomplished through the method of electromagnetically induced transparency. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kulikov, I (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 126-347, Pasadena, CA 91109 USA. EM kulikov@jpl.nasa.gov NR 15 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0950-0340 J9 J MOD OPTIC JI J. Mod. Opt. PD MAY 20 PY 2006 VL 53 IS 8 BP 1061 EP 1067 DI 10.1080/09500340500473422 PG 7 WC Optics SC Optics GA 036IU UT WOS:000237065600004 ER PT J AU Olson, JR Crawford, JH Chen, G Brune, WH Faloona, IC Tan, D Harder, H Martinez, M AF Olson, Jennifer R. Crawford, James H. Chen, Gao Brune, William H. Faloona, Ian C. Tan, David Harder, Hartwig Martinez, Monica TI A reevaluation of airborne HOx observations from NASA field campaigns SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID LASER-INDUCED FLUORESCENCE; WESTERN NORTH PACIFIC; PEM-TROPICS-B; UPPER TROPOSPHERE; OZONE PRODUCTION; OH; CHEMISTRY; NOX; PHOTOCHEMISTRY; AIRCRAFT AB [ 1] In situ observations of tropospheric HO2 obtained during four NASA airborne campaigns ( SUCCESS, SONEX, PEM-Tropics B and TRACE-P) are reevaluated using the NASA Langley time-dependent photochemical box model. Special attention is given to previously diagnosed discrepancies between observed and predicted HO2 which increase with higher NOx (NO + NO2) levels and at high solar zenith angles. This analysis shows that much of the model discrepancy at high NOx during SUCCESS can be attributed to modeling observations at timescales too long to capture the nonlinearity of HOx (OH+ HO2) chemistry under highly variable conditions for NOx. Discrepancies at high NOx during SONEX can be moderated to a large extent by complete use of all available precursor observations. Differences between kinetic rate coefficients and photolysis frequencies available for previous studies versus current recommendations also explain some of the disparity. Each of these causes is shown to exert greater influence with increasing NOx because of both the chemical nonlinearity between HOx and NOx and the increased sensitivity of HOx to changes in sources at high NOx. In contrast, discrepancies at high solar zenith angles will persist until an adequate nighttime source of HOx can be identified. It is important to note that other data sets from ground-based field studies show a similar discrepancy between observed and predicted HO2 for high NOx environments, and that the analysis presented here cannot resolve differences from those additional ground studies. Nevertheless, results from this study highlight important considerations in the application of box models to observationally based predictions of HOx radicals. C1 NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA. Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30306 USA. Max Planck Inst Chem, D-55128 Mainz, Germany. RP Olson, JR (reprint author), NASA, Langley Res Ctr, Div Atmospher Sci, MS 401B, Hampton, VA 23681 USA. EM j.r.olson@larc.nasa.gov RI Crawford, James/L-6632-2013; Harder, Hartwig/L-2511-2014 OI Crawford, James/0000-0002-6982-0934; Harder, Hartwig/0000-0002-6868-714X NR 43 TC 40 Z9 40 U1 1 U2 21 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 19 PY 2006 VL 111 IS D10 AR D10301 DI 10.1029/2005JD006617 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 049EZ UT WOS:000238000000001 ER PT J AU Vasavada, AR Horst, SM Kennedy, MR Ingersoll, AP Porco, CC Del Genio, AD West, RA AF Vasavada, A. R. Hoerst, S. M. Kennedy, M. R. Ingersoll, A. P. Porco, C. C. Del Genio, A. D. West, R. A. TI Cassini imaging of Saturn: Southern hemisphere winds and vortices SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID 1990 EQUATORIAL DISTURBANCE; GREAT RED SPOT; CLOUD STRUCTURE; ZONAL WINDS; JUPITERS ATMOSPHERE; VERTICAL STRUCTURE; IMAGES; GALILEO; SCIENCE; SYSTEM AB [ 1] High-resolution images of Saturn's southern hemisphere acquired by the Cassini Imaging Science Subsystem between February and October 2004 are used to create maps of cloud morphology at several wavelengths, to derive zonal winds, and to characterize the distribution, frequency, size, morphology, color, behavior, and lifetime of vortices. Nonequatorial wind measurements display only minor differences from those collected since 1981 and reveal a strong, prograde flow near the pole. The region just southward of the velocity minimum at 40.7 degrees S is especially active, containing numerous vortices, some generated in the proximity of convective storms. The two eastward jets nearest the pole display periodicity in their longitudinal structure, but no direct analogs to the northern hemisphere's polar hexagon or ribbon waves were observed. Characteristics of winds and vortices are compared with those of Saturn's northern hemisphere and Jupiter's atmosphere. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. Space Sci Inst, Cassini Imaging Cent Lab Operat, Boulder, CO USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Vasavada, AR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ashwin.r.vasavada@jpl.nasa.gov; horst@alumni.caltech.edu; megan.kennedy@asu.edu; api@gps.caltech.edu; carolyn@ciclops.org; adelgenio@giss.nasa.gov; robert.a.west@jpl.nasa.gov RI Horst, Sarah/A-9906-2010; Del Genio, Anthony/D-4663-2012 OI Horst, Sarah/0000-0003-4596-0702; Del Genio, Anthony/0000-0001-7450-1359 NR 36 TC 47 Z9 47 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 19 PY 2006 VL 111 IS E5 AR E05004 DI 10.1029/2005JE002563 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 049II UT WOS:000238009300001 ER PT J AU Seo, KW Wilson, CR Famiglietti, JS Chen, JL Rodell, M AF Seo, K. -W. Wilson, C. R. Famiglietti, J. S. Chen, J. L. Rodell, M. TI Terrestrial water mass load changes from gravity recovery and climate experiment (GRACE) SO WATER RESOURCES RESEARCH LA English DT Article ID TIME-VARIABLE GRAVITY; STORAGE; VARIABILITY; SYSTEM AB [ 1] Recent studies show that data from the Gravity Recovery and Climate Experiment ( GRACE) is promising for basin-to global-scale water cycle research. This study provides varied assessments of errors associated with GRACE water storage estimates. Thirteen monthly GRACE gravity solutions from August 2002 to December 2004 are examined, along with synthesized GRACE gravity fields for the same period that incorporate simulated errors. The synthetic GRACE fields are calculated using numerical climate models and GRACE internal error estimates. We consider the influence of measurement noise, spatial leakage error, and atmospheric and ocean dealiasing (AOD) model error as the major contributors to the error budget. Leakage error arises from the limited range of GRACE spherical harmonics not corrupted by noise. AOD model error is due to imperfect correction for atmosphere and ocean mass redistribution applied during GRACE processing. Four methods of forming water storage estimates from GRACE spherical harmonics ( four different basin filters) are applied to both GRACE and synthetic data. Two basin filters use Gaussian smoothing, and the other two are dynamic basin filters which use knowledge of geographical locations where water storage variations are expected. Global maps of measurement noise, leakage error, and AOD model errors are estimated for each basin filter. Dynamic basin filters yield the smallest errors and highest signal-to-noise ratio. Within 12 selected basins, GRACE and synthetic data show similar amplitudes of water storage change. Using 53 river basins, covering most of Earth's land surface excluding Antarctica and Greenland, we document how error changes with basin size, latitude, and shape. Leakage error is most affected by basin size and latitude, and AOD model error is most dependent on basin latitude. C1 Univ Texas, Ctr Space Res, Austin, TX 78712 USA. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Texas, Dept Geol Sci, Jackson Sch Geosci, Austin, TX 78712 USA. RP Seo, KW (reprint author), CALTECH, Jet Prop Lab, MS 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM weon.seo@jpl.nasa.gov; kiweon@geo.utexas.edu; jfamigli@uci.edu; chen@csr.utexas.edu; matthew.rodell@nasa.gov RI Rodell, Matthew/E-4946-2012 OI Rodell, Matthew/0000-0003-0106-7437 NR 17 TC 54 Z9 56 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 EI 1944-7973 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY 16 PY 2006 VL 42 IS 5 AR W05417 DI 10.1029/2005WR004255 PG 15 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 049KV UT WOS:000238016000002 ER PT J AU Keating, SM Bornstein, BJ Finney, A Hucka, M AF Keating, SM Bornstein, BJ Finney, A Hucka, M TI SBMLToolbox: an SBML toolbox for MATLAB users SO BIOINFORMATICS LA English DT Article AB We present SBMLToolbox, a toolbox that facilitates importing and exporting models represented in the Systems Biology Markup Language (SBML) in and out of the MATLAB environment and provides functionality that enables an experienced user of either SBML or MATLAB to combine the computing power of MATLAB with the portability and exchangeability of an SBML model. SBMLToolbox supports all levels and versions of SBML. C1 Univ Hertfordshire, Sci & Technol Res Inst, Hatfield AL10 9AB, Herts, England. NASA, Jet Prop Lab, Pasadena, CA USA. Physiom PLC, Oxford, England. CALTECH, Biol Network Modeling Ctr, Beckman Inst 13974, Pasadena, CA 91125 USA. RP Keating, SM (reprint author), Univ Hertfordshire, Sci & Technol Res Inst, Hatfield AL10 9AB, Herts, England. EM s.m.keating@herts.ac.uk RI Hucka, Michael/B-1896-2012; OI Keating, Sarah/0000-0002-3356-3542 FU NIGMS NIH HHS [R01 GM70923] NR 7 TC 64 Z9 66 U1 0 U2 4 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1367-4803 J9 BIOINFORMATICS JI Bioinformatics PD MAY 15 PY 2006 VL 22 IS 10 BP 1275 EP 1277 DI 10.1093/bioinformatics/btl111 PG 3 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Mathematical & Computational Biology; Statistics & Probability SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Computer Science; Mathematical & Computational Biology; Mathematics GA 039PS UT WOS:000237319300020 PM 16574696 ER PT J AU Grant, SB Ahn, JH Surbeck, CQ Jiang, SC Nezlin, NP DiGiacomo, PM AF Grant, SB Ahn, JH Surbeck, CQ Jiang, SC Nezlin, NP DiGiacomo, PM TI Response to comment on "Coastal water quality impact of stormwater runoff from an urban watershed in southern California" SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Letter ID SURF ZONE; ORANGE-COUNTY; POLLUTION; TRANSPORT C1 Univ Calif Irvine, Henry Samueli Sch Engn, Irvine, CA 92697 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. RP Grant, SB (reprint author), Univ Calif Irvine, Henry Samueli Sch Engn, Irvine, CA 92697 USA. RI DiGiacomo, Paul/F-5584-2010; Jiang, Sunny/H-7702-2012; Grant, Stanley/K-8179-2016 OI DiGiacomo, Paul/0000-0003-4550-1899; Jiang, Sunny/0000-0002-4993-8038; Grant, Stanley/0000-0001-6221-7211 NR 8 TC 0 Z9 0 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAY 15 PY 2006 VL 40 IS 10 BP 3441 EP 3442 DI 10.1021/es0607133 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 042JZ UT WOS:000237525500055 ER PT J AU Hou, TH AF Hou, TH TI Processing robustness for a phenylethynyl-terminated polyimide composite SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE composites; curing of polymers; polyimides; voids AB The processability of a phenylethynyl-terminated imide resin matrix (PETI-5) composite was investigated. Unidirectional prepregs were made through the coating of an N-methylpyrrolidone solution of an amide acid oligomer (PETAA-5/NMP) onto unsized IM7 fibers. Two batches of prepregs were used: one was made by the National Aeronautics and Space Administration in house, and the other was from an industrial Source. The composite processing robustness was investigated with respect to the prepreg shelf life, the effect of B-staging conditions, and the optimal processing window. The prepreg rheology and open hole compression (OHC) strengths were not to affected by prolonged ambient storage (i.e., up to 60 days). Rheological measurements indicated that the PETAA-5/NMP processability was only slightly affected over a wide range of B-stage temperatures (from 250 to 300 degrees C). The OHC strength values were statistically indistinguishable among laminates consolidated under various B-staging conditions. An optimal processing window was established with response surface methodology. The IM7/PETAA-5/NMP prepreg was more sensitive to the consolidation temperature than to the pressure. A good consolidation was achievable at 371 degrees C (700 degrees F)/100 psi, which yielded a room-temperature OHC strength of 62 ksi. However, the processability declined dramatically at temperatures below 350 degrees C (662 degrees F), as evidenced by the OHC strength values. The processability of the IM7/PETI-5 prepreg was robust. (c) 2006 Wiley Periodicals, Inc. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Hou, TH (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 11 TC 5 Z9 5 U1 0 U2 8 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD MAY 15 PY 2006 VL 100 IS 4 BP 3212 EP 3221 DI 10.1002/app.21625 PG 10 WC Polymer Science SC Polymer Science GA 027NZ UT WOS:000236423600080 ER PT J AU Antonakakis, JN Bhargava, P Chuang, KC Zehnder, AT AF Antonakakis, JN Bhargava, P Chuang, KC Zehnder, AT TI Linear viscoelastic properties of HFPE-II-52 polyimide SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE high temperature materials; mechanical properties; polyimides; viscoelastic properties; Prony series ID COMPOSITES; INTERCONVERSION; SHEAR AB The polyimide HFPE-II-52 was developed at NASA Glenn Research Center for use as a matrix in high temperature composite materials. The unique properties of such composites stem largely from the performance of the matrix at high temperature. Thus, as part of a larger effort to Study high temperature composite materials, the linear viscoelastic properties of HFPE are measured and a mathematical model of the properties is developed. In particular, storage, loss, and stress relaxation moduli were obtained from cyclic and transient loading experiments. A Prony series was fit to the relaxation modulus data. As a cross check, the fit to the relaxation modulus was converted to storage and loss moduli and compared with those measured directly. Effects of postcuring and of moisture on the properties are investigated as well. These results provide researchers with a constitutive model for HFPE-II-52 and provide some insight into the performance of HFPE matrix composites at high temperatures. (c) 2006 Wiley Periodicals, Inc. C1 Cornell Univ, Dept Theoret & Appl Mech, Ithaca, NY 14853 USA. NASA, Glenn Res Ctr, Div Polymers, Cleveland, OH 44135 USA. RP Zehnder, AT (reprint author), Cornell Univ, Dept Theoret & Appl Mech, Ithaca, NY 14853 USA. EM atz2@cornell.edu RI Zehnder, Alan/E-7458-2012 NR 30 TC 12 Z9 12 U1 0 U2 7 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD MAY 15 PY 2006 VL 100 IS 4 BP 3255 EP 3263 DI 10.1002/app.23067 PG 9 WC Polymer Science SC Polymer Science GA 027NZ UT WOS:000236423600084 ER PT J AU Wu, MLC Schubert, SD Suarez, MJ Pegion, PJ Waliser, DE AF Wu, Man-Li C. Schubert, Siegfried D. Suarez, Max J. Pegion, Philip J. Waliser, Duane E. TI Seasonality and meridional propagation of the MJO SO JOURNAL OF CLIMATE LA English DT Article ID SUMMER INTRASEASONAL OSCILLATION; FREQUENCY EQUATORIAL WAVES; SHEARED ZONAL FLOW; BOREAL SUMMER; TROPICAL ATMOSPHERE; CIRCULATION; MONSOON; CONVECTION; MODEL; TEMPERATURE AB The Madden-Julian oscillation (MJO) is known to have a substantial impact on the variability of the Asian-Australian summer monsoons. An important, but not well understood, aspect of the MJO-monsoon connection is the meridional propagation of bands of enhanced or reduced precipitation that are especially pronounced during the northern Summer. In this study, the nature of the seasonality of the MJO is examined, with a focus on the meridional propagation, using both observations and simulations with an atmospheric general circulation model (AGCM). A key result is that the AGCM, when forced with idealized eastward propagating equatorial dipole heating anomalies, reproduces the salient features of the observed seasonality in the precipitation and wind fields associated with the MJO, including meridional propagation into the Indian and Australian summer monsoon regions. An analysis of the simulations and observations shows that the off-equatorial precipitation anomalies are initiated by surface frictional convergence/divergence associated with the Rossby wave response to the leading pole of the equatorial heating dipole. The off-equatorial precipitation anomalies develop further by interacting with the trailing pole of the equatorial dipole heating to produce a northwest-southeast (or southwest-northeast) oriented line of surface convergence/divergence that propagates to the east. Since the prescribed heating does not vary by season. the seasonal asymmetry in the response must be the result of the seasonal changes in the background state. In particular, the results suggest that seasonal changes in both the vertical wind shear and static stability play a role. C1 NASA, Goddard Space Flight Ctr, Earth Sun Explorat Div, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. NASA, Jet Propuls Lab, Pasadena, CA USA. RP Wu, MLC (reprint author), NASA, Goddard Space Flight Ctr, Earth Sun Explorat Div, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA. EM man-li.c.wu@nasa.gov RI Pegion, Philip/E-5247-2012 NR 47 TC 22 Z9 23 U1 1 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD MAY 15 PY 2006 VL 19 IS 10 BP 1901 EP 1921 DI 10.1175/JCLI3680.1 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 045YN UT WOS:000237778700002 ER PT J AU Jensen, MP Del Genio, AD AF Jensen, MP Del Genio, AD TI Factors limiting convective cloud-top height at the ARM Nauru Island climate research facility SO JOURNAL OF CLIMATE LA English DT Article ID TROPICAL WESTERN PACIFIC; TOGA-COARE; BOUNDARY-LAYER; PART II; DRY AIR; HUMIDITY; MICROPHYSICS; VARIABILITY; SENSITIVITY; RADIOSONDE AB Cumulus congestus clouds, with moderate shortwave albedos and cloud-top temperatures near freezing, occur fairly often in the Tropics. These clouds may play an important role in the evolution of the Madden-Julian oscillation and the regulation of relative humidity in the midtroposphere. Despite this importance they are not necessarily simulated very well in global climate models. Surface remote sensing observations and soundings from the Atmospheric Radiation Measurement (ARM) climate research facility at Nauru Island are coupled with a simple parcel model in order to address the following questions about these cloud types: 1) Which environmental factors play a role in determining the depth of tropical convective clouds? 2) What environmental parameters are related to entrainment rate in cumulus congestus clouds? The results presented herein suggest that at Nauru Island a drying of the midtroposphere is more likely to be responsible for limiting congestus cloud-top heights than is a stabilizing of the freezing level. It is also found that low-level CAPE and the RH profile account for the largest portion of the variance in cumulus congestus entrainment rates, consistent with the idea that entrainment rate depends on the buoyant production of turbulent kinetic energy. If the analysis is limited to cases where there is a sounding during the hour preceding the cumulus congestus observations, it is found that the low-level CAPE accounts for 85% of the total variance in entrainment rate. C1 Columbia Univ, Dept Appl Phys & Appl Math, New York, NY USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Jensen, MP (reprint author), Brookhaven Natl Lab, ESD, ESSD, Bldg 490D, Upton, NY 11973 USA. EM mjensen@bnl.gov RI Del Genio, Anthony/D-4663-2012 OI Del Genio, Anthony/0000-0001-7450-1359 NR 34 TC 56 Z9 56 U1 1 U2 8 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAY 15 PY 2006 VL 19 IS 10 BP 2105 EP 2117 DI 10.1175/JCLI3722.1 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 045YN UT WOS:000237778700014 ER PT J AU Dold, P Szofran, FR Benz, KW AF Dold, P Szofran, FR Benz, KW TI Thermoelectromagnetic convection in vertical Bridgman grown germanium-silicon SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE fluid flows; magnetic field; mass transfer; segregation; thermoelectromagnetic convection; semiconducting materials ID ROTATING MAGNETIC-FIELD; FLOATING-ZONE GROWTH; CRYSTAL-GROWTH; MELT FLOW; GE1-XSIX AB The effect of thermoelectromagnetic convection (TEMC) was investigated in the system germanium silicon, grown by the vertical Bridgman method under axial static magnetic fields of up to 5 T. TEMC is generated, if thermocurrents, caused by concentration and/or temperature gradients, are running non-parallel to magnetic field lines. Under the influence of strong axial magnetic fields, the macro segregation along the growth axis changed from a profile typical for normal freezing toward a concentration profile described by diffusive mass transport. At the same time, the segregation pattern on the microscale (i.e. the non-steady distribution of the silicon incorporation perpendicular to the growth axis) changed significantly. Without magnetic field, no evidence of short-range compositional fluctuations has been detected. Growth under static magnetic fields of B >= 0.5 T and B <= 4 T resulted in strong microsegregation. These compositional fluctuations are in the range of a few micrometers up to several hundred micrometers. The strength increased with the field strength and reached a maximum at a magnetic induction of 2 T. These magnetic field induced inhomogeneities are damped with higher magnetic fields and can nearly be eliminated with a magnetic field of 5 T. Due to their coupling to the static magnetic field and their specific shape, they can be attributed to TEMC. (c) 2006 Elsevier B.V. All rights reserved. C1 Univ Freiburg, Inst Kristallog, D-79104 Freiburg, Germany. Univ Freiburg, FMF, D-79104 Freiburg, Germany. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Dold, P (reprint author), Tohoku Univ, Grad Sch Sci, Sendai, Miyagi 9808578, Japan. EM p.dold@ganko.tohoku.ac.jp NR 16 TC 15 Z9 16 U1 1 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY 15 PY 2006 VL 291 IS 1 BP 1 EP 7 DI 10.1016/j.jcrysgro.2006.02.055 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 049CU UT WOS:000237993900001 ER PT J AU Kundu, PK Bell, TL AF Kundu, Prasun K. Bell, Thomas L. TI Space-time scaling behavior of rain statistics in a stochastic fractional diffusion model SO JOURNAL OF HYDROLOGY LA English DT Article; Proceedings Paper CT International Conference on Fractals in the Hydrosciences (Hydrofractals 03) CY AUG, 2003 CL Ascona, SWITZERLAND DE rain statistics; space-time scaling; Stochastic models; fractional diffusion ID ANOMALOUS DIFFUSION; MESOSCALE RAINFALL; GAUGE DATA AB Statistical properties of rain exhibit the interesting feature that they depend in a nontrivial way on the length and time scales over which rain rate is averaged. A quantitative understanding of this dependence can be utilized to relate statistics at different scales and is important for inter-comparison of rainfall data obtained from measuring devices with differing space-time resolutions. A stochastic dynamical model of rainfall based on a fractional diffusion type kinetic equation introduced earlier by the authors describes fairly well how the second moment statistics of area-averaged rain rate depend on the averaging length L and predicts a power law scaling behavior as L -> 0. The model pictures the correlation of the precipitation field as arising from two-dimensional Levy flights. The present paper extends the investigation to the full space-time covariance function of the precipitation field. In particular, a scaling regime is identified in which the various second moment statistics of area- and/or time-averaged rain field exhibit invariance under a combined rescaling of the space and time variables-a property known as dynamic scaling, the scaling exponent being identified with the Levy index. Although the space and time scales resolved in the radar data used to establish the model turn out to be too coarse for the dynamic scaling behavior to be experimentally demonstrated, we predict that it should be observable in high frequency rain gauge data from dense gauge networks. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Maryland Baltimore Cty, JCET, Catonsville, MD 21228 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Kundu, PK (reprint author), Univ Maryland Baltimore Cty, JCET, Catonsville, MD 21228 USA. EM kundu@climate.gsfc.nasa.gov RI Kundu, Prasun/C-7212-2013 OI Kundu, Prasun/0000-0002-2284-9852 NR 18 TC 8 Z9 9 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD MAY 15 PY 2006 VL 322 IS 1-4 BP 49 EP 58 DI 10.1016/j.jhydro1.2005.02.031 PG 10 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 045UN UT WOS:000237768100005 ER PT J AU Fetzer, EJ AF Fetzer, Eric J. TI Preface to special section: Validation of Atmospheric Infrared Sounder Observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Editorial Material ID RADIATIVE-TRANSFER MODEL; AIRS; AIRS/AMSU/HSB; SATELLITE; AQUA; CALIBRATION; PARAMETERS; RETRIEVAL; MISSION; WATER C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Fetzer, EJ (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM eric.j.fetzer@jpl.nasa.gov NR 42 TC 27 Z9 27 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 13 PY 2006 VL 111 IS D9 AR D09S01 DI 10.1029/2005JD007020 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046GY UT WOS:000237800700009 ER PT J AU Marshak, A Platnick, S Varnai, T Wen, GY Cahalan, RF AF Marshak, Alexander Platnick, Steven Varnai, Tamas Wen, Guoyong Cahalan, Robert F. TI Impact of three-dimensional radiative effects on satellite retrievals of cloud droplet sizes SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID INDEPENDENT PIXEL APPROXIMATION; NEURAL-NETWORK RETRIEVAL; OPTICAL-THICKNESS; BOUNDARY-LAYER; INHOMOGENEOUS CLOUDS; EFFECTIVE RADIUS; SCATTERING; AEROSOL; DEPTH; STRATOCUMULUS AB [1] There are several dozen papers that study the effects of cloud horizontal inhomogeneity on the retrievals of cloud optical thickness, but only a few of them deal with cloud droplet sizes. This paper is one of the first comprehensive attempts to fill this gap: It takes a close theoretical look at the radiative effects of cloud 3-D structure in retrievals of droplet effective radii. Under some general assumptions, it was found that ignoring subpixel ( unresolved) variability produces a negative bias in the retrieved effective radius, while ignoring cloud inhomogeneity at scales larger than a pixel scale ( resolved variability), on the contrary, leads to overestimation of the domain average droplet size. The theoretical results are illustrated with examples from Large Eddy Simulations (LES) of cumulus (Cu) and stratocumulus (Sc) cloud fields. The analysis of cloud drop size distributions retrieved from both LES fields confirms that ignoring shadowing in 1-D retrievals results in substantial overestimation of effective radii which is more pronounced for broken Cu than for Sc clouds. Collocated measurements of broken Cu clouds by Moderate Resolution Imaging Spectrometer ( MODIS) and Advanced Spaceborne Thermal Emission and Reflection Radiometer ( ASTER) are used to check simulations and theory with observations. The analysis of ASTER and MODIS data and associated derived products recommends against blindly using retrieved effective radii for broken cloud fields, especially if one wants to relate aerosol amounts to cloud droplet sizes. C1 NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21250 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. RP Marshak, A (reprint author), NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. EM alexander.marshak@nasa.gov RI Marshak, Alexander/D-5671-2012; Cahalan, Robert/E-3462-2012; Platnick, Steven/J-9982-2014 OI Cahalan, Robert/0000-0001-9724-1270; Platnick, Steven/0000-0003-3964-3567 NR 42 TC 93 Z9 95 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 13 PY 2006 VL 111 IS D9 AR D09207 DI 10.1029/2005JD006686 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046GY UT WOS:000237800700008 ER PT J AU Jezek, K Rodriguez, E Gogineni, P Freeman, A Curlander, J Wu, XQ Paden, J Allen, C AF Jezek, K Rodriguez, E Gogineni, P Freeman, A Curlander, J Wu, XQ Paden, J Allen, C TI Glaciers and Ice Sheets Mapping Orbiter concept SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID FARADAY-ROTATION; ANTARCTICA AB [ 1] We describe a concept for a spaceborne radar system designed to measure the surface and basal topography of terrestrial ice sheets and to determine the physical properties of the glacier bed. Our primary objective is to develop this new technology for obtaining spaceborne estimates of the thickness of the polar ice sheets with an ultimate goal of providing essential information to modelers estimating the mass balance of the polar ice sheets and estimating the response of ice sheets to changing climate. Our new technology concept employs VHF and P-band interferometric radars using a novel clutter rejection technique for measuring surface and bottom topographies of polar ice sheets from aircraft and spacecraft. Our approach will enable us to reduce signal contamination from surface clutter, measure the topography of the glacier bed at better than 1 km intervals with an accuracy of 20 m, and paint a picture of variations in bed characteristics. The technology will also have applications for planetary exploration including studies of the Martian ice caps and the icy moons of the outer solar system. Through the concept developed here we believe that we can image the base and map the three-dimensional basal topography beneath an ice sheet at up to 5 km depth. C1 Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Kansas, Dept Elect Engn & Comp Sci, Lawrence, KS 66045 USA. Vexcel Corp, Boulder, CO 80301 USA. RP Jezek, K (reprint author), Ohio State Univ, Byrd Polar Res Ctr, 108 Scott Hall,1090 Carmack Rd, Columbus, OH 43210 USA. EM jezek.1@osu.edu NR 18 TC 4 Z9 4 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 13 PY 2006 VL 111 IS E6 AR E06S20 DI 10.1029/2005JE002572 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 046HI UT WOS:000237801800002 ER PT J AU Xu, YB Cummer, SA Farrell, WM AF Xu, YB Cummer, SA Farrell, WM TI Application of an orbital radar sounder model to detecting Martian polar subsurface features SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MARS; WATER; IONOSPHERE; SIMULATION; OPERATION; LAYER AB [ 1] A model to simulate the complete planetary orbital radar sounder problem is presented in this paper. The subsurface features and the ionosphere will not only bring ambiguity to the collected radar sounder data, but also critically affect instrument capabilities. These environmental uncertainties generate a compelling need for meaningful quantitative simulation of the orbital radar sounder problem. Our model combines finite difference time domain (FDTD) and analytical methods and splits the computational volume into two pieces owing to the large size of the simulation space. The near-surface and subsurface fields are computed with the FDTD method to improve the simulation flexibility of the surface and subsurface features. The two-way ionospheric propagation is treated with the simpler but accurate near-far field transformation method to maximize computational efficiency. With the capability of including all of the important radar sounder effects that can be difficult to compute analytically, the model enables accurate numerical experimentation with realistic instrumental and environmental parameters, and can handle an arbitrarily two-dimensionally inhomogeneous ground and an arbitrary ionospheric profile. Simulation results are given on the application of detecting Martian polar subsurface water, and we place bounds on the ionospheric losses and the subsurface conductivity through which water can be detected. We find that a basal lake located similar to 2.5 km below the surface is near the limit of detectability. The ionospheric losses should be no larger than 10 dB and the average subsurface conductivity should be no larger than 4 x 10(-6) S/m for the basal lake to be detectable. C1 Duke Univ, Dept Elect & Comp Engn, Durham, NC 27708 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Xu, YB (reprint author), Duke Univ, Dept Elect & Comp Engn, Durham, NC 27708 USA. EM ybxu@ee.duke.edu RI Cummer, Steven/A-6118-2008; Farrell, William/I-4865-2013 OI Cummer, Steven/0000-0002-0002-0613; NR 29 TC 3 Z9 3 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 13 PY 2006 VL 111 IS E6 AR E06S17 DI 10.1029/2005JE002547 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 046HI UT WOS:000237801800001 ER PT J AU Susskind, J Barnet, C Blaisdell, J Iredell, L Keita, F Kouvaris, L Molnar, G Chahine, M AF Susskind, Joel Barnet, Chris Blaisdell, John Iredell, Lena Keita, Fricky Kouvaris, Lou Molnar, Gyula Chahine, Moustafa TI Accuracy of geophysical parameters derived from Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit as a function of fractional cloud cover SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SEA-SURFACE; AIRS/AMSU/HSB; PRODUCTS; EMISSIVITY; AIRS AB AIRS was launched on EOS Aqua on 4 May 2002, together with AMSU A and HSB, to form a next generation polar orbiting infrared and microwave atmospheric sounding system. The primary products of AIRS/AMSU are twice daily global fields of atmospheric temperature-humidity profiles, ozone profiles, sea/land surface skin temperature, and cloud related parameters including OLR. The sounding goals of AIRS are to produce 1 km tropospheric layer mean temperatures with an RMS error of 1 K, and layer precipitable water with an RMS error of 20%, in cases with up to 80% effective cloud cover. The basic theory used to analyze AIRS/AMSU/HSB data in the presence of clouds, called the at-launch algorithm, was described previously. Prelaunch simulation studies using this algorithm indicated that these results should be achievable. Some modifications have been made to the at-launch retrieval algorithm as described in this paper. Sample fields of parameters retrieved from AIRS/AMSU/HSB data are presented and validated as a function of retrieved fractional cloud cover. As in simulation, the degradation of retrieval accuracy with increasing cloud cover is small and the RMS accuracy of lower-tropospheric temperature retrieved with 80% cloud cover is about 0.5 K poorer than for clear cases. HSB failed in February 2003, and consequently, HSB channel radiances are not used in the results shown in this paper. The AIRS/AMSU retrieval algorithm described in this paper, called version 4, become operational at the Goddard DAAC (Distributed Active Archive Center) in April 2003 and is being used to analyze near-real time AIRS/AMSU data. Historical AIRS/AMSU data, going backward from March 2005 through September 2002, is also being analyzed by the DAAC using the version 4 algorithm. C1 NASA, Goddard Space Flight Ctr, Sci Applicat Int Corp, Greenbelt, MD 20771 USA. NOAA, Natl Environm Satellite Data & Informat Serv, Camp Springs, MD 20746 USA. Jet Prop Lab, Pasadena, CA 94709 USA. NASA, Goddard Space Flight Ctr, Joint Ctr Earth Syst Technol, Greenbelt, MD 20771 USA. RP Susskind, J (reprint author), NASA, Goddard Space Flight Ctr, Sci Applicat Int Corp, Greenbelt, MD 20771 USA. EM joel.susskind-1@nasa.gov RI Barnet, Christopher/F-5573-2010 NR 14 TC 71 Z9 71 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 12 PY 2006 VL 111 IS D9 AR D09S17 DI 10.1029/2005JD006272 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046GW UT WOS:000237800500002 ER PT J AU Lee, YK Yang, P Hu, YX Baum, BA Loeb, NG Gao, BC AF Lee, Yong-Keun Yang, Ping Hu, Yongxiang Baum, Bryan A. Loeb, Norman G. Gao, Bo-Cai TI Potential nighttime contamination of CERES clear-sky fields of view by optically thin cirrus during the CRYSTAL-FACE campaign SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIANT ENERGY SYSTEM; ANGULAR-DISTRIBUTION MODELS; RADIATIVE FLUX ESTIMATION; MEASURING MISSION SATELLITE; WATER-VAPOR; PART I; MICROPHYSICAL PROPERTIES; PLANETARY ATMOSPHERES; SCATTERING PROPERTIES; MULTIPLE-SCATTERING AB [1] We investigate the outgoing broadband longwave ( LW, 5 similar to 200 mu m) and window ( WIN, 8 similar to 12 mu m) channel radiances at the top of atmosphere (TOA) under clear-sky conditions, using data acquired by the Cloud and the Earth's Radiant Energy System (CERES) and Moderate-Resolution Imaging Spectroradiometer ( MODIS) instruments on board the NASA Terra satellite platform. In this study, detailed analyses are performed on the CERES Single Scanner Footprint TOA/Surface Fluxes and Clouds product to understand the radiative effect of thin cirrus. The data are acquired over the Florida area during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers - Florida Area Cirrus Experiment (CRYSTAL-FACE) field program. Of particular interest is the anisotropy associated with the radiation field. Measured CERES broadband radiances are compared to those obtained from rigorous radiative transfer simulations. Analysis of results from this comparison indicates that the simulated radiances tend to be larger than their measured counterparts, with differences ranging from 2.1% to 8.3% for the LW band and from 1.7% to 10.6% for the WIN band. The averaged difference in radiance is approximately 4% for both the LW and WIN channels. A potential cause for the differences could be the presence of thin cirrus (i.e., optically thin ice clouds with visible optical thicknesses smaller than approximately 0.3). The detection and quantitative analysis of these thin cirrus clouds are challenging even with sophisticated multispectral instruments. While large differences in radiance between the CERES observations and the theoretical calculations are found, the corresponding difference in the anisotropic factors is very small (0.2%). Furthermore, sensitivity studies show that the influence due to a +/- 1 K bias of the surface temperature on the errors of the LW and WIN channel radiances is of the same order as that associated with a +/- 2% bias of the surface emissivity. The LW and WIN errors associated with a +/- 5% bias of water vapor amount in the lower atmosphere in conjunction with a +/- 50% bias of water vapor amount in the upper atmosphere is similar to that of a +/- 1 K bias of the vertical temperature profile. Even with the uncertainties considered for these various factors, the simulated LW and WIN radiances are still larger than the observed radiances if thin cirrus clouds are excluded. C1 Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Hampton Univ, Hampton, VA 23668 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. RP Lee, YK (reprint author), Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. EM pyang@ariel.met.tamu.edu RI Hu, Yongxiang/K-4426-2012; LEE, YONG-KEUN/A-1352-2015; Yang, Ping/B-4590-2011; Baum, Bryan/B-7670-2011 OI Baum, Bryan/0000-0002-7193-2767 NR 51 TC 3 Z9 3 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 11 PY 2006 VL 111 IS D9 AR D09203 DI 10.1029/2005JD006372 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 046GU UT WOS:000237800300002 ER PT J AU Thevar, T Barnes, NP AF Thevar, Thangavel Barnes, Norman P. TI Diode-pumped, continuous-wave Tm : YAlO3 laser SO APPLIED OPTICS LA English DT Article AB A continuous-wave, diode-pumped, room-temperature Tm:YAlO3 laser was built, characterized, and compared with a theoretical model. Spectroscopic parameters of the laser crystal, such as the pump band (H-3(4), manifold) lifetime, the upper laser level (F-3(4) manifold) lifetime, and the absorption coefficient were measured. The experimental data were used to calculate the quantum efficiency of Tm self-quenching of the H-3(4) manifold. (c) 2006 Optical Society of America. C1 Univ Aberdeen, Kings Coll, Dept Engn, Aberdeen AB24 3UE, Scotland. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Thevar, T (reprint author), Univ Aberdeen, Kings Coll, Dept Engn, Aberdeen AB24 3UE, Scotland. EM t.thevar@abdn.ac.uk NR 13 TC 16 Z9 16 U1 0 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAY 10 PY 2006 VL 45 IS 14 BP 3352 EP 3355 DI 10.1364/AO.45.003352 PG 4 WC Optics SC Optics GA 041PB UT WOS:000237467000019 PM 16676041 ER PT J AU Beelen, A Cox, P Benford, DJ Dowell, CD Kovacs, A Bertoldi, F Omont, A Carilli, CL AF Beelen, A Cox, P Benford, DJ Dowell, CD Kovacs, A Bertoldi, F Omont, A Carilli, CL TI 350 mu m dust emission from high-redshift quasars SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : evolution; galaxies : starburst; infrared : galaxies; infrared : ISM; quasars : individual (APM 08279+5255, HS 1002+4400, KUV 08086+4037, J1409+5628, PSS 2322+1944; SDSS J1148+5251) ID ABSORPTION-LINE QUASAR; SPECTRAL ENERGY-DISTRIBUTION; UNIVERSE GALAXY SURVEY; APM 08279+5255; MOLECULAR GAS; HOST GALAXY; SUBMILLIMETER OBSERVATIONS; PHOTOMETRIC REDSHIFTS; MAMBO/IRAM-30 M; STELLAR OBJECT AB We report detections of six high-redshift (1: 8 <= z <= 6: 4), optically luminous, radio-quiet quasars at 350 mu m, using the SHARC II bolometer camera at the Caltech Submillimeter Observatory. Our observations double the number of high-redshift quasars for which 350 mu m photometry is available. By combining the 350 mu m measurements with observations at other submillimeter/millimeter wavelengths, for each source we have determined the temperature of the emitting dust ( ranging from 40 to 60 K) and the far-infrared luminosity [(0.6-2.2) x 10(13) L-circle dot]. The combined mean spectral energy distribution of all high-redshift quasars with two or more rest-frame far-infrared photometric measurements is best fit with a graybody with temperature of 47 +/- 3 K and a dust emissivity power-law spectral index of beta = 1.6 +/- 0.1. This warm dust component is a good tracer of the starburst activity of the quasar host galaxy. The ratio of the far-infrared to radio luminosities of infrared-luminous, radio-quiet high-redshift quasars is consistent with that found for local star-forming galaxies. C1 Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. Max Planck Inst Radioastron, D-53121 Bonn, Germany. Univ Bonn, Inst Radioastron, D-53121 Bonn, Germany. Inst Radio Astron Millimetr, F-38406 St Martin Dheres, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. CNRS, Inst Astrophys Paris, F-75014 Paris, France. Univ Paris 06, F-75014 Paris, France. Natl Radio Astron Observ, Socorro, NM 87801 USA. RP Beelen, A (reprint author), Univ Paris 11, Inst Astrophys Spatiale, Batiment 121, F-91405 Orsay, France. EM alexandre.beelen@ias.u-psud.fr; cox@iram.fr; dominic.benford@nasa.gov; cdd@submm.caltech.edu; attila@submm.caltech.edu; bertoldi@astro.uni-bonn.de; omont@iap.fr; ccarilli@aoc.nrao.edu RI Benford, Dominic/D-4760-2012; Kovacs, Attila/C-1171-2010 OI Benford, Dominic/0000-0002-9884-4206; Kovacs, Attila/0000-0001-8991-9088 NR 44 TC 171 Z9 172 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 694 EP 701 DI 10.1086/500636 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200006 ER PT J AU Lewis, KT Eracleous, M AF Lewis, KT Eracleous, M TI Black hole masses of active galaxies with double-peaked Balmer emission lines SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; galaxies : active; galaxies : nuclei ID GALACTIC NUCLEI; BROAD-LINE; ACCRETION DISK; LONG-TERM; 3C 390.3; ARP 102B; VELOCITY DISPERSIONS; PROFILE VARIABILITY; SKY SURVEY; NGC 4203 AB We have obtained near-IRspectra of five AGNs that exhibit double-peaked Balmer emission lines (NGC 1097, Pictor A, PKS 0921-213, 1E 0450.30-1817, and IRAS 0236.6-3101). The stellar velocity dispersions of the host galaxies were measured from the Ca (II) lambda lambda 8494, 8542, 8662 absorption lines and were found to range from 140 to 200 km s(-1). Using the well-known correlation between the black hole mass and the stellar velocity dispersion, the black hole masses in these galaxies were estimated to range from 4 x 10(7) to 1.2 x 10(8) M-circle dot. We supplement the observations presented here with estimates of the black holes masses for five additional double-peaked emitters (Arp 102B, 3C 390.3, NGC 4579, NGC 4203, and M81) obtained by other authors using similar methods. Using these black hole masses, we infer the ratio of the bolometric luminosity to the Eddington luminosity, (L-bol/L-Edd). We find that two objects ( Pictor A and PKS 0921-213) have L-bol/L-Edd similar to 0.2, whereas the other objects have L-bol/L-Edd less than or similar to 10(-2) (nearby, low-luminosity double-peaked emitters are the most extreme, with L-bol/L-Edd less than or similar to 10(-4)). The physical timescales in the outer regions of the accretion disks (at r similar to 10(3)GM/c(2)) in these objects were also estimated and range from a few months for the dynamical timescale to several decades for the sound crossing timescale. The profile variability in these objects is typically an order of magnitude longer than the dynamical time, but we note that variability occurring on the dynamical timescale has not been ruled out by the observations. C1 Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. RP Lewis, KT (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. EM ktlewis@milkyway.gsfc.nasa.gov NR 80 TC 56 Z9 56 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 711 EP 719 DI 10.1086/501419 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200008 ER PT J AU Ptuskin, VS Moskalenko, IV Jones, FC Strong, AW Zirakashvili, VN AF Ptuskin, VS Moskalenko, IV Jones, FC Strong, AW Zirakashvili, VN TI Dissipation of magnetohydrodynamic waves on energetic particles: Impact on interstellar turbulence and cosmic-ray transport SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; diffusion; elementary particles; MHD; turbulence; waves ID DENSITY POWER SPECTRUM; PARTIAL CROSS-SECTIONS; MAGNETIC-FIELD; HELIUM SPECTRA; ALFVENIC TURBULENCE; MHD-TURBULENCE; SOLAR MINIMUM; WIND-DRIVEN; PROPAGATION; PROTON AB The physical processes involved in diffusion of Galactic cosmic rays in the interstellar medium are addressed. We study the possibility that the nonlinear MHD cascade sets the power-law spectrum of turbulence that scatters charged energetic particles. We find that the dissipation of waves due to the resonant interaction with cosmic-ray particles may terminate the Kraichnan-type cascade below wavelengths 10(13) cm. The effect of this wave dissipation has been incorporated in the GALPROP numerical propagation code in order to asses the impact on measurable astrophysical data. The energy dependence of the cosmic-ray diffusion coefficient found in the resulting self-consistent model may explain the peaks in the secondary to primary nuclei ratios observed at about 1 GeV nucleon(-1). C1 Inst Terr Magnetism Ionosphere & Radio Wave Propa, Troitsk 142190, Moscow Region, Russia. Stanford Univ, Hansen Expt Phys Lab, Stanford, CA 94305 USA. NASA, Goddard Space Flight Ctr, Explorat Universe Div, Code 661, Greenbelt, MD 20771 USA. Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94309 USA. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. RP Ptuskin, VS (reprint author), Inst Terr Magnetism Ionosphere & Radio Wave Propa, Troitsk 142190, Moscow Region, Russia. EM vptuskin@izmiran.rssi.ru; imos@stanford.edu; Frank.C.Jones@gsfc.nasa.gov; aws@mpe.mpg.de; zirak@mpimail.mpi-hd.mpg.de RI Moskalenko, Igor/A-1301-2007 OI Moskalenko, Igor/0000-0001-6141-458X NR 97 TC 134 Z9 137 U1 1 U2 7 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 902 EP 916 DI 10.1086/501117 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200023 ER PT J AU Hollis, JM Remijan, AJ Jewell, PR Lovas, FJ AF Hollis, JM Remijan, AJ Jewell, PR Lovas, FJ TI Cyclopropenone (c-H2C3O): A new interstellar ring molecule SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : clouds; ISM : individual (Sagittarius B2(N)); ISM : molecules; radio lines : ISM ID ELECTRIC-DIPOLE MOMENT; MICROWAVE-SPECTRUM; GALACTIC-CENTER; QUADRUPOLE MOMENTS; WAVE SPECTRUM; ACETIC-ACID; G VALUES; MILLIMETER; GLYCOLALDEHYDE; STARK AB The three-carbon keto ring cyclopropenone (c-H2C3O) has been detected largely in absorption with the 100 m Green Bank Telescope (GBT) toward the star-forming region Sagittarius B2(N) by means of a number of rotational transitions between energy levels that have energies less than 10 K. Previous negative results from searches for interstellar c-H2C3O by other investigators attempting to detect rotational transitions that have energy levels similar to 10 K or greater indicate no significant hot core component. Thus, we conclude that only the low-energy levels of c-H2C3O are populated because the molecule state temperature is low, suggesting that c-H2C3O resides in a star-forming core halo region that has a widespread arcminute spatial scale. Toward Sagittarius B2(N), the GBT was also used to observe the previously reported, spatially ubiquitous, three-carbon ring cyclopropenylidene (c-C3H2), which has a divalent carbon that makes it highly reactive in the laboratory. The presence of both c-C3H2 and c-H2C3O toward Sagittarius B2(N) suggests that gas-phase oxygen addition may account for the synthesis of c-H2C3O from c-C3H2. We also searched for but did not detect the three-carbon sugar glyceraldehyde (CH2OHCHOHCHO). C1 NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Hollis, JM (reprint author), NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Code 606, Greenbelt, MD 20771 USA. NR 48 TC 43 Z9 43 U1 0 U2 16 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 933 EP 939 DI 10.1086/501121 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200026 ER PT J AU Young, ET Teixeira, PS Lada, CJ Muzerolle, J Persson, SE Murphy, DC Siegler, N Marengo, M Krause, O Mainzer, AK AF Young, ET Teixeira, PS Lada, CJ Muzerolle, J Persson, SE Murphy, DC Siegler, N Marengo, M Krause, O Mainzer, AK TI Spitzer and Magellan observations of NGC 2264: A remarkable star-forming core near IRS 2 SO ASTROPHYSICAL JOURNAL LA English DT Article DE open clusters and associations : individual (NGC 2264); stars : formation; stars : pre-main-sequence ID INITIAL MASS FUNCTION; MULTIBAND IMAGING PHOTOMETER; OB1 MOLECULAR CLOUD; NGC 2264; INTERMEDIATE-MASS; DARK CLOUD; CLUSTER; PROTOCLUSTERS; OUTFLOWS; OBJECTS AB We analyze Spitzer and Magellan observations of a star-forming core near IRS 2 in the young cluster NGC 2264. The submillimeter source IRAS 12 S1, previously believed to be an intermediate-mass Class 0 object is shown to be a dense collection of embedded, low-mass stars. We argue that this group of stars represents the fragmenting collapse of a dense, turbulent core, using a number of indicators of extreme youth. With reasonable estimates for the velocity dispersion in the group, we estimate a dynamical lifetime of only a few times 10(4) yr. Spectral energy distributions of stars in the core are consistent with Class I or Class 0 assignments. We present observations of an extensive system of molecular hydrogen emission knots. The luminosity of the objects in the core region are consistent with roughly solar mass protostars. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Lisbon, Fac Ciencias, Dept Fis, Lisbon, Portugal. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Young, ET (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. RI Teixeira, Paula Stella/O-2289-2013 OI Teixeira, Paula Stella/0000-0002-3665-5784 NR 27 TC 23 Z9 23 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 972 EP 978 DI 10.1086/501227 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200030 ER PT J AU Prochaska, JX Bloom, JS Chen, HW Foley, RJ Perley, DA Ramirez-Ruiz, E Granot, J Lee, WH Pooley, D Alatalo, K Hurley, K Cooper, MC Dupree, AK Gerke, BF Hansen, BMS Kalirai, JS Newman, JA Rich, RM Richer, H Stanford, SA Stern, D van Breugel, WJM AF Prochaska, JX Bloom, JS Chen, HW Foley, RJ Perley, DA Ramirez-Ruiz, E Granot, J Lee, WH Pooley, D Alatalo, K Hurley, K Cooper, MC Dupree, AK Gerke, BF Hansen, BMS Kalirai, JS Newman, JA Rich, RM Richer, H Stanford, SA Stern, D van Breugel, WJM TI The galaxy hosts and large-scale environments of short-hard gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; stars : formation; stars : neutron ID STAR-FORMATION; SHORT-DURATION; FORMATION RATES; NEUTRON-STARS; GRB 050509B; AFTERGLOW; GRB-050709; REDSHIFT; CONSTRAINTS; RESOLUTION AB The rapid succession of discoveries of short-duration hard-spectrum gamma-ray bursts (GRBs) has led to unprecedented insights into the energetics of the explosion and nature of the progenitors. Yet short of the detection of a smoking gun, such as a burst of coincident gravitational radiation or a Li-Paczynski minisupernova, it is unlikely that a definitive claim can be made for the progenitors. As was the case with long-duration soft-spectrum GRBs, however, the expectation is that a systematic study of the hosts and locations of short GRBs could begin to yield fundamental clues as to their nature. We present an aggregate study of the host galaxies of short-duration hard-spectrum GRBs. In particular, we present the Gemini-North and Keck discovery spectra of the galaxies that hosted three short GRBs and a moderate-resolution ( R approximate to 6000) spectrum of a fourth host. We find that these short-hard GRBs originate in a variety of low-redshift (z < 1) environments that differ substantially from those of long-soft GRBs, both on individual galaxy scales and on galaxy-cluster scales. Specifically, three of the bursts are found to be associated with old and massive galaxies with no current (< 0.1 M-circle dot yr(-1)) or recent star formation. Two of these galaxies are located within a cluster environment. These observations support an origin from the merger of compact stellar remnants, such as double neutron stars or a neutron star-black hole binary. The fourth event, in contrast, occurred within a dwarf galaxy with a star formation rate exceeding 0.3 M-circle dot yr(-1). Therefore, it appears that like supernovae of Type Ia, the progenitors of short-hard bursts are created in all galaxy types, suggesting a corresponding class with a wide distribution of delay times between formation and explosion. C1 Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Inst Adv Study, Princeton, NJ 08540 USA. Stanford Univ, KIPAC, Stanford, CA 94309 USA. Natl Autonomous Univ Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Calif Berkeley, Inst Nucl & Particle Astrophys, Berkeley, CA 94720 USA. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Prochaska, JX (reprint author), Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. OI Alatalo, Katherine/0000-0002-4261-2326 NR 50 TC 73 Z9 73 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 989 EP 994 DI 10.1086/501160 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200032 ER PT J AU Kilic, M von Hippel, T Mullally, F Reach, WT Kuchner, MJ Winget, DE Burrows, A AF Kilic, M von Hippel, T Mullally, F Reach, WT Kuchner, MJ Winget, DE Burrows, A TI The mystery deepens: Spitzer observations of cool white dwarfs SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; stars : individual (LHS 1126, WD 0038-226); white dwarfs ID DIGITAL-SKY-SURVEY; EXCESS INFRARED RADIATION; SPACE-TELESCOPE; MODEL ATMOSPHERES; ARRAY CAMERA; DISCOVERY; DISK; GD-362; STARS AB We present 4.5 and 8 mu m photometric observations of 18 cool white dwarfs obtained with the Spitzer Space Telescope. Our observations demonstrate that four white dwarfs with T-eff < 6000 K show slightly depressed mid-infrared fluxes relative to white dwarf models. In addition, another white dwarf with a peculiar optical and near-infrared spectral energy distribution (LHS 1126) is found to display significant flux deficits in Spitzer observations. These mid-infrared flux deficits are not predicted by the current white dwarf models including collision-induced absorption due to molecular hydrogen. We postulate that either the collision-induced absorption calculations are incomplete or there are other unrecognized physical processes occurring in cool white dwarf atmospheres. The spectral energy distribution of LHS 1126 surprisingly fits a Rayleigh-Jeans spectrum in the infrared, mimicking a hot white dwarf with effective temperature well in excess of 105 K. This implies that the source of this flux deficit is probably not molecular absorption but some other process. C1 Univ Texas, Dept Astron, Austin, TX 78712 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Arizona, Dept Astron, Tucson, AZ 85721 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Kilic, M (reprint author), Univ Texas, Dept Astron, 1 Univ Stn C1400, Austin, TX 78712 USA. EM kilic@astro.as.utexas.edu RI Kuchner, Marc/E-2288-2012; OI Reach, William/0000-0001-8362-4094 NR 40 TC 25 Z9 25 U1 1 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 1051 EP 1056 DI 10.1086/501042 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200039 ER PT J AU Hillier, DJ Gull, T Nielsen, K Sonneborn, G Iping, R Smith, N Corcoran, M Damineli, A Hamann, FW Martin, JC Weis, K AF Hillier, D. John Gull, T. Nielsen, K. Sonneborn, G. Iping, R. Smith, Nathan Corcoran, M. Damineli, A. Hamann, F. W. Martin, J. C. Weis, K. TI The UV scattering halo of the central source associated with eta Carinae SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : atmospheres; stars : early-type; stars : fundamental parameters; stars : individual (eta Carinae); stars : mass loss; ultraviolet : stars ID RADIATION-DRIVEN WINDS; HOT LUMINOUS STARS; X-RAY-EMISSION; HOMUNCULUS-NEBULA; FE-II; STELLAR WIND; ULTRAVIOLET-SPECTRUM; SPECTROSCOPIC EVENT; INFRARED MORPHOLOGY; BINARY HYPOTHESIS AB We have made an extensive study of the UV spectrum of eta Carinae and find that we do not directly observe the star and its wind in the UV. Because of dust along our line of sight, the UV light that we observe arises from bound-bound scattering at large impact parameters. We obtain a reasonable fit to the UV spectrum by using only the flux that originates outside 0''033. This explains why we can still observe the primary star in the UV despite the large optical extinction: it is due to the presence of an intrinsic coronagraph in the eta Car system and to the extension of the UV-emitting region. It is not due to peculiar dust properties alone. We have computed the spectrum of the purported companion star and show that it could only be directly detected in the UV spectrum, preferentially in the FUSE spectral region (912 - 1175 A). However, we find no direct evidence for a companion star, with the properties indicated by X-ray studies and studies of the Weigelt blobs, in UV spectra. This might be due to reprocessing of the companion's light by the dense stellar wind of the primary. Broad Fe II and [Fe II] emission lines, which form in the stellar wind, are detected in spectra taken in the southeastern lobe, 0''2 from the central star. The wind spectrum shows some similarities to the spectra of the B and D Weigelt blobs but also shows some marked differences in that lines pumped by Ly alpha are not seen. The detection of the broad lines lends support to our interpretation of the UV spectrum and to our model for eta Car. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NASA, Goddard Space Flight Ctr, Lab Observat Cosmol, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508900 Sao Paulo, Brazil. Univ Florida, Dept Astron, Bryant Space Sci Ctr 211, Gainesville, FL 32611 USA. Univ Minnesota, Dept Phys & Astron, Minneapolis, MN 55455 USA. Ruhr Univ Bochum, Inst Astron, D-44780 Bochum, Germany. RP Hillier, DJ (reprint author), Univ Pittsburgh, Dept Phys & Astron, 3941 Ohara St, Pittsburgh, PA 15260 USA. RI Sonneborn, George/D-5255-2012; Damineli, Augusto/D-8210-2012; Gull, Theodore/D-2753-2012 OI Damineli, Augusto/0000-0002-7978-2994; Gull, Theodore/0000-0002-6851-5380 NR 99 TC 55 Z9 55 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 1098 EP 1116 DI 10.1086/501225 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200043 ER PT J AU Nishikawa, KI Hardee, PE Hededal, CB Fishman, GJ AF Nishikawa, KI Hardee, PE Hededal, CB Fishman, GJ TI Acceleration mechanics in relativistic shocks by the Weibel instability SO ASTROPHYSICAL JOURNAL LA English DT Article DE acceleration of particles; instabilities; plasmas; shock waves ID MAGNETIC-FIELD GENERATION; ELECTRON-POSITRON PLASMA; RAY BURST SOURCES; PARTICLE-ACCELERATION; EMISSION; WAVES AB Plasma instabilities (e.g., Buneman, Weibel, and other two-stream instabilities) created in collisionless shocks may be responsible for particle ( electron, positron, and ion) acceleration. Using a three-dimensional relativistic electromagnetic particle code, we have investigated long-term particle acceleration associated with relativistic electron-ion or electron-positron jet fronts propagating into an unmagnetized ambient electron-ion or electron-positron plasma. These simulations have been performed with a longer simulation system than our previous simulations in order to investigate the nonlinear stage of the Weibel instability and its particle acceleration mechanism. The current channels generated by the Weibel instability are surrounded by toroidal magnetic fields and radial electric fields. This radial electric field is quasi stationary and accelerates particles that are then deflected by the magnetic field. Whether particles are accelerated or decelerated along the jet propagation direction depends on the velocity of particles and the sign of E x B in the moving frame of each particle. For the electron-ion case the large-scale current channels generated by the ion Weibel instability lead to more acceleration near the jet head. Consequently, the accelerated jet electrons in the electron-ion jet have a significant hump above a thermal distribution. However, in the electron-positron case, accelerated jet electrons have a smoother, nearly thermal distribution. In the electron-positron case, initial acceleration occurs as current channels form and then continues at a much lesser rate as the current channels and corresponding toroidal magnetic fields generated by the Weibel instability dissipate. C1 Natl Space & Technol Ctr, Huntsville, AL 35805 USA. Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA. Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen, Denmark. Natl Space Sci & Technol Ctr, NASA, Marshall Space Flight Ctr, Huntsville, AL 35805 USA. RP Nishikawa, KI (reprint author), Natl Space & Technol Ctr, Huntsville, AL 35805 USA. EM ken-ichi.nishikawa@nsstc.nasa.gov; phardee@bama.ua.edu NR 29 TC 59 Z9 59 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP 1267 EP 1274 DI 10.1086/501426 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UC UT WOS:000237554200058 ER PT J AU Bhattacharyya, S Strohmayer, TE AF Bhattacharyya, S Strohmayer, TE TI Spreading of thermonuclear flames on the neutron star in SAX J1808.4-3658: An observational tool SO ASTROPHYSICAL JOURNAL LA English DT Article DE equation of state; methods : data analysis; stars : neutron; X-rays : binaries; X-rays : bursts; X-rays : individual (SAX J1808.4-3658) ID X-RAY-BURSTS; MILLISECOND PULSAR; BRIGHTNESS OSCILLATIONS; COHERENT OSCILLATIONS; FREQUENCY EVOLUTION; LIGHT CURVES; RISING PHASE; PROPAGATION; COMPACTNESS; EXPANSION AB We analyze archival Rossi X-Ray Timing Explorer (RXTE) proportional counter array (PCA) data of thermonuclear X-ray bursts from the 2002 outburst of the accreting millisecond pulsar SAX J1808.4 - 3658. We present evidence of nonmonotonic variations of oscillation frequency during burst rise, and correlations among the time evolution of the oscillation frequency, amplitude, and the inferred burning region area. We also find that the amplitude and burning region area evolutions are consistent with thermonuclear flames spreading on the neutron star surface. Based on this discussion, we infer that for the 2002 October 15 thermonuclear burst, the ignition likely occurred in the midlatitudes, the burning region took similar to 0.2 s to nearly encircle the equatorial region of the neutron star, and after that the lower amplitude oscillation originated from the remaining asymmetry of the burning front in the same hemisphere where the burst ignited. Our observational findings and theoretical discussion indicate that studies of the evolution of burst oscillation properties during burst rise can provide a powerful tool to understand thermonuclear flame spreading on neutron star surfaces under extreme physical conditions. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Explorat Universe Div, Greenbelt, MD 20771 USA. RP Bhattacharyya, S (reprint author), Univ Maryland, Dept Astron, College Pk, MD 20742 USA. EM sudip@milkyway.gsfc.nasa.gov; stroh@clarence.gsfc.nasa.gov NR 24 TC 15 Z9 15 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP L161 EP L164 DI 10.1086/504841 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UD UT WOS:000237554300019 ER PT J AU Della Valle, M Malesani, D Bloom, JS Benetti, S Chincarini, G D'Avanzo, P Foley, RJ Covino, S Melandri, A Piranomonte, S Tagliaferri, G Stella, L Gilmozzi, R Antonelli, LA Campana, S Chen, HW Filliatre, P Fiore, F Fugazza, D Gehrels, N Hurley, K Mirabel, IF Pellizza, LJ Piro, L Prochaska, JX AF Della Valle, M Malesani, D Bloom, JS Benetti, S Chincarini, G D'Avanzo, P Foley, RJ Covino, S Melandri, A Piranomonte, S Tagliaferri, G Stella, L Gilmozzi, R Antonelli, LA Campana, S Chen, HW Filliatre, P Fiore, F Fugazza, D Gehrels, N Hurley, K Mirabel, IF Pellizza, LJ Piro, L Prochaska, JX TI Hypernova signatures in the late rebrightening of GRB 050525A SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; supernovae : individual (GRB 050525A) ID GAMMA-RAY BURST; INFRARED LIGHT CURVES; SUPERNOVA 2002AP; SN 2002AP; AFTERGLOW; DISCOVERY; ENERGY; SPECTROSCOPY; GRB-011121; PHOTOMETRY AB We report observations of GRB 050525A, for which a Gemini North spectrum shows its redshift to be z = 0.606 . This is the third closest long GRB discovered by Swift. We observed its afterglow using the VLT, Gemini, and TNG telescopes to search for an associated supernova. We find that the early-time light curve is described by a broken power law with a break at days after the burst. About 5 days after the burst, a flattening is apparent, followed t similar to 0.3 by a further dimming. Both the magnitude and the shape of the light curve suggest that a supernova was emerging during the late decay of the afterglow. This supernova, named SN 2005nc, had a rise time faster than SN 1998bw and a long-lasting maximum. A spectrum obtained about 20 days (rest frame) after the GRB resembles the spectrum of SN 1998bw obtained close to maximum light. C1 Osserv Astrofis Arcetri, Ist Nazl Astrofis, I-50125 Florence, Italy. Univ Calif Santa Barbara, Kavl Inst Theoret Phys, Santa Barbara, CA 93106 USA. Sch Adv Int Studies, I-34014 Trieste, Italy. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Osserv Astron Padova, Ist Nazl Astrofis, I-35122 Padua, Italy. Osserv Astron Brera, Ist Nazl Astrofis, I-23807 Merate, LC, Italy. Univ Milan Bicocca, Dipartimento Fis, I-20126 Milan, Italy. Univ Insubria, Dipartimento Matemat & Fis, I-22100 Como, Italy. John Moores Univ, Astrophys Res Inst, Birkenhead CH41, Merseyside, England. Osserv Astron Roma, Ist Nazl Astrofis, I-00040 Monte Porzio Catone, Roma, Italy. European So Observ, D-85748 Garching, Germany. MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Lab Astroparticule & Cosmol, UMR 7164, F-75231 Paris 05, France. CEA, Serv Astrophys, DSM, DAPNIA,CE Saclay, F-91191 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. European So Observ, Santiago 19, Chile. Univ Paris 07, CNRS,CEA Saclay, CEA,Serv Astrophys, AIM,UMR 7158, F-91191 Gif Sur Yvette, France. Inst Nazl Astrofis, IASF, Sez Roma, I-00113 Rome, Italy. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. RP Della Valle, M (reprint author), Osserv Astrofis Arcetri, Ist Nazl Astrofis, Largo E Fermi 5, I-50125 Florence, Italy. RI Gehrels, Neil/D-2971-2012; PIRO, LUIGI/E-4954-2013; OI PIRO, LUIGI/0000-0003-4159-3984; Della Valle, Massimo/0000-0003-3142-5020; Covino, Stefano/0000-0001-9078-5507; Tagliaferri, Gianpiero/0000-0003-0121-0723; Fiore, Fabrizio/0000-0002-4031-4157 NR 58 TC 64 Z9 64 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP L103 EP L106 DI 10.1086/504636 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UD UT WOS:000237554300005 ER PT J AU Engelbracht, CW Kundurthy, P Gordon, KD Rieke, GH Kennicutt, RC Smith, JDT Regan, MW Makovoz, D Sosey, M Draine, BT Helou, G Armus, L Calzetti, D Meyer, M Bendo, GJ Walter, F Hollenbach, D Cannon, JM Murphy, EJ Dale, DA Buckalew, BA Sheth, K AF Engelbracht, CW Kundurthy, P Gordon, KD Rieke, GH Kennicutt, RC Smith, JDT Regan, MW Makovoz, D Sosey, M Draine, BT Helou, G Armus, L Calzetti, D Meyer, M Bendo, GJ Walter, F Hollenbach, D Cannon, JM Murphy, EJ Dale, DA Buckalew, BA Sheth, K TI Extended mid-infrared aromatic feature emission in M82 SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; galaxies : individual (M82); galaxies : ISM; galaxies : peculiar; galaxies : starburst ID NEARBY GALAXIES SURVEY; INITIAL MASS FUNCTION; STAR-FORMATION; GALACTIC SUPERWINDS; STARBURST GALAXIES; INFRARED-EMISSION; SPACE-TELESCOPE; PAH EMISSION; H-ALPHA; NGC 253 AB We present new images (ground-based optical and mid-infrared [MIR] from the Spitzer Space Telescope) and spectra (from Spitzer) of the archetypal starburst galaxy M82. The Spitzer data show that the MIR emission extends at least 6 kpc along the minor axis of the galaxy. We use the optical and infrared data to demonstrate that the extended emission is dominated by emission from dust. The colors of the MIR emission and the spectra indicate that there is a strong component of aromatic feature emission (the MIR features commonly attributed to polycyclic aromatic hydrocarbons). The dust continuum and aromatic feature emission are both strong in the well-known superwind region of this galaxy; clearly, the carrier of the aromatic features can survive in close proximity to the wind, far from the plane of the galaxy. We also see significant emission by dust well outside the superwind region, providing the clearest picture to date of the dust distribution in the halo of this galaxy. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, London SW7 2BW, England. Max Planck Inst Astron, D-69117 Heidelberg, Germany. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. RP Engelbracht, CW (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM cengelbracht@as.arizona.edu OI Draine, Bruce/0000-0002-0846-936X NR 46 TC 93 Z9 94 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP L127 EP L132 DI 10.1086/504590 PN 2 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UD UT WOS:000237554300011 ER PT J AU Milligan, RO Gallagher, PT Mathioudakis, M Keenan, FP AF Milligan, RO Gallagher, PT Mathioudakis, M Keenan, FP TI Observational evidence of gentle chromospheric evaporation during the impulsive phase of a solar flare SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : atmospheric motions; Sun : flares; Sun : UV radiation; Sun : x-rays, gamma rays ID LOOP RADIATIVE HYDRODYNAMICS; GRADUAL PHASE; RHESSI; ULTRAVIOLET; EMISSION; MODELS AB Observational evidence of gentle chromospheric evaporation during the impulsive phase of a C9.1 solar flare is presented using data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager and the Coronal Diagnostic Spectrometer on board the Solar and Heliospheric Observatory. Until now, evidence of gentle evaporation has often been reported during the decay phase of solar flares, where thermal conduction is thought to be the driving mechanism. Here we show that the chromospheric response to a low flux of nonthermal electrons (>= 5 cm(-2) s(-1)) results in plasma upflows of 13 +/- 16, 16 +/- 18, and 110 +/- 58 km s(-1) in the cool He I and O V emission lines and the 8 MK Fe XIX line, respectively. These findings, in conjunction with other recently reported work, now confirm that the dynamic response of the solar atmosphere is sensitively dependent on the flux of incident electrons. C1 Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. Trinity Coll Dublin, Sch Phys, Dublin, Ireland. RP Milligan, RO (reprint author), Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. RI Gallagher, Peter/C-7717-2011 OI Gallagher, Peter/0000-0001-9745-0400 NR 17 TC 54 Z9 54 U1 1 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2006 VL 642 IS 2 BP L169 EP L171 DI 10.1086/504592 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042UD UT WOS:000237554300021 ER PT J AU Tan, XF Salama, F AF Tan, Xiaofeng Salama, Farid TI Cavity ring-down spectroscopy of jet-cooled 1-pyrenecarboxyaldehyde (C17H10O) and 1-methylpyrene (C17H12) cations SO CHEMICAL PHYSICS LETTERS LA English DT Article ID DIFFUSE INTERSTELLAR BANDS; POLYCYCLIC AROMATIC-HYDROCARBONS; INHOMOGENEOUS ELECTRON-GAS; DENSITY-FUNCTIONAL THEORY; BASIS-SETS; APPROXIMATION; TRANSITION; ENERGY; ATOMS AB To study the correlation between pyrene-like species and the diffuse interstellar bands (DIBs), we have investigated the electronic transitions of 1-pyrenecarboxaldehyde(+) and 1-methylpyrene(+) which were prepared with a pulsed discharge slit nozzle and detected by cavity ring-down spectroscopy. Several vibronic bands were observed near the gimel 4428 DIB is detected. Time-dependent density functional theory calculations were performed to aid the assignment of these bands. It is found that none of the observed bands correlate with the gimel 4428 DIB. The effect of side groups on the vibronic spectrum of pyrene(+) is discussed. Published by Elsevier B.V. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Tan, XF (reprint author), NASA, Ames Res Ctr, Div Space Sci, Mail Stop 245-6, Moffett Field, CA 94035 USA. EM x.tan@jhu.edu; farid.salama@nasa.gov RI Salama, Farid/A-8787-2009 OI Salama, Farid/0000-0002-6064-4401 NR 30 TC 14 Z9 14 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 EI 1873-4448 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD MAY 10 PY 2006 VL 422 IS 4-6 BP 518 EP 521 DI 10.1016/j.cplett.2006.03.006 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 046VW UT WOS:000237840200044 ER PT J AU Zhang, B Harb, JN Davis, RC Choi, S Kim, JW Miller, T Chu, SH Watt, GD AF Zhang, B Harb, JN Davis, RC Choi, S Kim, JW Miller, T Chu, SH Watt, GD TI Electron exchange between Fe(II)-horse spleen ferritin and Co(III)/Mn(III) reconstituted horse spleen and Azotobacter vinelandii ferritins SO BIOCHEMISTRY LA English DT Article ID CARBON-MONOXIDE DEHYDROGENASE; MAMMALIAN FERRITIN; IRON RELEASE; PROTEIN CAGE; RHODOSPIRILLUM-RUBRUM; MOLECULAR-DIFFUSION; LISTERIA-INNOCUA; REDOX REACTIVITY; GOLD ELECTRODES; COBALT AB Azotobacter vinelandii bacterioferritin (AvBF) containing 800-1500 Co or Mn atoms as Co(III) and Mn(III) oxyhydroxide cores (Co-AvBF, Mn-AvBF) was synthesized by the same procedure used previously for horse spleen ferritin (HoSF). The kinetics of reduction of Co-AvBF and Mn-AvBF by ascorbic acid are first-order in each reactant. The rate constant for the reduction of Mn-AvBF (8.52 M-1 min(-1)) is similar to 12 times larger than that for Co-AvBF (0.72 M-1 min(-1)), which is consistent with a previous observation that Mn-HoSF is reduced similar to 10-fold faster than Co-HoSF [Zhang, B. et al. (2005) Inorg. Chent. 44, 3738-3745]. The rates of reduction of M-AvBF (M = Co and Mn) are more than twice that for the reduction of the corresponding M-HoSF. HoSF containing reduced Fe(II) cores (Fe(II)-HoSF), prepared by methyl viologen and CO, also reduces M-HoSF and M-AvBF species, with both cores remaining within ferritin, suggesting that electrons transfer through the ferritin shell. Electron transfer from Fe(II)-HoSF to Co-AvBF occurs at a rate similar to 3 times faster than that to Co-HoSF, indicating that the Co cores in AvBF are more accessible to reduction than the Co cores in HoSF. The presence of nonconductive (SiO2) or conductive (gold) surfaces known to bind ferritins enhances the rate of electron transfer. A more than similar to 4-fold increase in the apparent reaction rate is observed in the presence of gold. Although both surfaces (SiO2 and gold) enhance reaction by providing binding sites for molecular interaction, results show that ferritins with different mineral cores bound to a gold surface transfer electrons through the gold substrate so that direct contact of the reacting molecules is not required. C1 Brigham Young Univ, Dept Chem & Biochem, Provo, UT 84602 USA. Brigham Young Univ, Dept Chem Engn, Provo, UT 84602 USA. Brigham Young Univ, Dept Phys, Provo, UT 84602 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Watt, GD (reprint author), Brigham Young Univ, Dept Chem & Biochem, Provo, UT 84602 USA. EM gdwatt@chem.byu.edu RI Kim, Jae-Woo/A-8314-2008 NR 42 TC 13 Z9 13 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD MAY 9 PY 2006 VL 45 IS 18 BP 5766 EP 5774 DI 10.1021/bi060164d PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 041QZ UT WOS:000237472100009 PM 16669620 ER PT J AU Flood, AH Wong, EW Stoddart, JF AF Flood, Amar H. Wong, Eric W. Stoddart, J. Fraser TI Models of charge transport and transfer in molecular switch tunnel junctions of bistable catenanes and rotaxanes SO CHEMICAL PHYSICS LA English DT Article DE hopping; molecular electronics; molecular machines; Raman spectroscopy; tunneling ID SELF-ASSEMBLED MONOLAYERS; NEGATIVE DIFFERENTIAL RESISTANCE; LINEAR MOTOR-MOLECULES; ELECTRON-TRANSFER; TETRATHIAFULVALENE UNIT; DEVICES; REDOX; NANOSCALE; STATE; SILICON AB The processes by which charge transfer can occur play a foundational role in molecular electronics. Here we consider simplified models of the transfer processes that could be present in bistable molecular switch tunnel junction (MSTJ) devices during one complete cycle of the device from its low- to high- and back to low-conductance state. The bistable molecular switches, which are composed of a monolayer of either switchable catenanes or rotaxanes, exist in either a ground-state co-conformation or a metastable one in which the conduction properties of the two co-conformations, when measured at small biases (+0.1 V), are significantly different irrespective of whether transport is dominated by tunneling or hopping. The voltage-driven generation (+/- 2 V) of molecule-based redox states, which are sufficiently long-lived to allow the relative mechanical movements necessary to switch between the two co-conformations, rely upon unequal charge transfer rates on to and/or off of the molecules. Surface-enhanced Raman spectroscopy has been used to image the ground state of the bistable rotaxane in MSTJ-Iike devices. Consideration of these models provide new ways of looking at molecular electronic devices that rely, not only on nanoscale charge-transport, but also upon the bustling world of molecular motion in mechanically interlocked bistable molecules. (c) 2005 Elsevier B.V. All rights reserved. C1 Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Flood, AH (reprint author), Indiana Univ, Dept Chem, 800 E Kirkwood Ave, Bloomington, IN 47405 USA. EM aflood@indiana.edu RI Stoddart, James /H-1518-2011; Flood, Amar/B-3863-2016 NR 67 TC 36 Z9 36 U1 3 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD MAY 9 PY 2006 VL 324 IS 1 BP 280 EP 290 DI 10.1016/j.chemphys.2005.12.031 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 045TV UT WOS:000237766300028 ER PT J AU Sheta, EF Moses, RW Huttsell, LJ AF Sheta, EF Moses, RW Huttsell, LJ TI Active smart material control system for buffet alleviation SO JOURNAL OF SOUND AND VIBRATION LA English DT Article AB Vertical tail buffeting is a serious multidisciplinary problem that limits the performance and maneuverability of twin-tail fighter aircraft. The buffet problem occurs at high angles of attack when the vortical flow breaks down ahead of the vertical tails resulting in unsteady and unbalanced loads on the tails leading to their premature fatigue failure. An active smart material control system, using distributed piezoelectric (PZT) actuators, is developed for buffet alleviation and is presented. The surfaces of the vertical tail are equipped with PZT actuators to control the buffet responses in the first bending and torsion modes. The electrodynamics of the PZT actuators are modeled using a finite-element model. A singleinput/single-output controller is designed to drive the active PZT actuators. High-fidelity analysis modules for the fluid dynamics, structural dynamics, electrodynamics of the PZT actuators, control law, fluid-structure interfacing, and and motion are integrated into a multidisciplinary computing environment that controls the temporal synchronization of the analysis modules. The results of this study indicate that the actively controlled PZT actuators are an effective tool for buffet alleviation over wide range of angels of attack. Peak values of power spectral density of tail-tip acceleration are reduced by as much as 22% in the first bending mode and by as much as 82% in the first torsion mode. The root mean square values of tail-tip acceleration are reduced by as much as 12%. (c) 2005 Elsevier Ltd. All rights reserved. C1 CFD Res Corp, Huntsville, AL 35805 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. USAF, Res Lab, Dayton, OH USA. RP Sheta, EF (reprint author), CFD Res Corp, 215 Wynn Dr, Huntsville, AL 35805 USA. EM efs@cfdrc.com NR 22 TC 20 Z9 21 U1 2 U2 5 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD MAY 9 PY 2006 VL 292 IS 3-5 BP 854 EP 868 DI 10.1016/j.jsv.2005.09.002 PG 15 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 025AW UT WOS:000236238700028 ER PT J AU Estabrook, FB AF Estabrook, Frank B. TI Conservation laws for vacuum tetrad gravity SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article ID NONLINEAR EVOLUTION-EQUATIONS; GENERAL-RELATIVITY; PROLONGATION STRUCTURES; FIELD; SYSTEMS AB Ten conservation laws in useful polynomial form are derived from a Cartan form and exterior differential system (EDS) for the tetrad equations of vacuum general relativity. The Noether construction of conservation laws for well-posed EDSs is introduced first, and an illustration given, deriving 15 conservation laws of the free field Maxwell equations from symmetries of its EDS. The Maxwell EDS and tetrad gravity EDS have parallel structures, with their numbers of dependent variables, numbers of generating 2-forms and generating 3-forms, and Cartan character tables all in the ratio of 1 to 4. They have ten corresponding symmetries with the same Lorentz algebra and ten corresponding conservation laws. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Estabrook, FB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM frank.estabrook@jpl.nasa.gov NR 32 TC 7 Z9 7 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAY 7 PY 2006 VL 23 IS 9 BP 2841 EP 2848 DI 10.1088/0264-9381/23/9/005 PG 8 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 050KW UT WOS:000238087300006 ER PT J AU Arellano, AF Kasibhatla, PS Giglio, L van der Werf, GR Randerson, JT Collatz, GJ AF Arellano, AF Kasibhatla, PS Giglio, L van der Werf, GR Randerson, JT Collatz, GJ TI Time-dependent inversion estimates of global biomass-burning CO emissions using Measurement of Pollution in the Troposphere (MOPITT) measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TRACE-P OBSERVATIONS; CARBON-MONOXIDE; ATMOSPHERIC CO2; NORTH-AMERICA; SATELLITE-OBSERVATIONS; TROPICAL ATLANTIC; TRANSPORT MODEL; FOREST-FIRES; ART.; OZONE AB [ 1] We present an inverse-modeling analysis of CO emissions using column CO retrievals from the Measurement of Pollution in the Troposphere (MOPITT) instrument and a global chemical transport model (GEOS-CHEM). We first focus on the information content of MOPITT CO column retrievals in terms of constraining CO emissions associated with biomass burning and fossil fuel/biofuel use. Our analysis shows that seasonal variation of biomass-burning CO emissions in Africa, South America, and Southeast Asia can be characterized using monthly mean MOPITT CO columns. For the fossil fuel/biofuel source category the derived monthly mean emission estimates are noisy even when the error statistics are accurately known, precluding a characterization of seasonal variations of regional CO emissions for this source category. The derived estimate of CO emissions from biomass burning in southern Africa during the June - July 2000 period is significantly higher than the prior estimate ( prior, 34 Tg; posterior, 13 Tg). We also estimate that emissions are higher relative to the prior estimate in northern Africa during December 2000 to January 2001 and lower relative to the prior estimate in Central America and Oceania/Indonesia during April - May and September - October 2000, respectively. While these adjustments provide better agreement of the model with MOPITT CO column fields and with independent measurements of surface CO from National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory at background sites in the Northern Hemisphere, some systematic differences between modeled and measured CO fields persist, including model overestimation of background surface CO in the Southern Hemisphere. Characterizing and accounting for underlying biases in the measurement model system are needed to improve the robustness of the top-down estimates. C1 Duke Univ, Nicholas Sch Environm & Earth Sci, Durham, NC 27708 USA. Sci Syst & Applicat Inc, Lanham, MD USA. Vrije Univ Amsterdam, Fac Earth & Life Sci, NL-1081 HV Amsterdam, Netherlands. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Natl Ctr Atmospher Res, Div Atmospher Chem, POB 3000, Boulder, CO 80307 USA. EM arellano@ucar.edu RI Arellano, Avelino, Jr./F-5674-2010; Kasibhatla, Prasad/A-2574-2010; collatz, george/D-5381-2012; Chem, GEOS/C-5595-2014; van der Werf, Guido/M-8260-2016; OI van der Werf, Guido/0000-0001-9042-8630; Kasibhatla, Prasad/0000-0003-3562-3737 NR 64 TC 58 Z9 59 U1 1 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 6 PY 2006 VL 111 IS D9 AR D09303 DI 10.1029/2005JD006613 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 041ID UT WOS:000237447100004 ER PT J AU Lopez, JP Fridlind, AM Jost, HJ Loewenstein, M Ackerman, AS Campos, TL Weinstock, EM Sayres, DS Smith, JB Pittman, JV Hallar, AG Avallone, LM Davis, SM Herman, RL AF Lopez, JP Fridlind, AM Jost, HJ Loewenstein, M Ackerman, AS Campos, TL Weinstock, EM Sayres, DS Smith, JB Pittman, JV Hallar, AG Avallone, LM Davis, SM Herman, RL TI CO signatures in subtropical convective clouds and anvils during CRYSTAL-FACE: An analysis of convective transport and entrainment using observations and a cloud-resolving model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TRACE GAS-TRANSPORT; STRATOSPHERIC-TROPOSPHERIC EXPERIMENT; OZONE PRODUCTION; NUMERICAL SIMULATIONS; DEEP CONVECTION; JULY 10; TROPICAL PACIFIC; MESOSCALE MODEL; SULFUR-DIOXIDE; UNITED-STATES AB [1] Convective systems are an important mechanism in the transport of boundary layer air into the upper troposphere. The Cirrus Regional Study of Tropical Anvils and Cirrus Layers - Florida Area Cirrus Experiment ( CRYSTAL-FACE) campaign, in July 2002, was developed as a comprehensive atmospheric mission to improve knowledge of subtropical cirrus systems and their roles in regional and global climate. In situ measurements of carbon monoxide ( CO), water vapor ( H(2)Ov), and total water (H(2)Ot) aboard NASA's WB-57F aircraft and CO aboard the U. S. Navy's Twin Otter aircraft were obtained to study the role of convective transport. Three flights sampled convective outflow on 11, 16 and 29 July found varying degrees of CO enhancement relative to the free troposphere. A cloud-resolving model used the in situ observations and meteorological fields to study these three systems. Several methods of filtering the observations were devised here using ice water content, relative humidity with respect to ice, and particle number concentration as a means to statistically sample the model results to represent the flight tracks. A weighted histogram based on ice water content observations was then used to sample the simulations for the three flights. In addition, because the observations occurred in the convective outflow cirrus and not in the storm cores, the model was used to estimate the maximum CO within the convective systems. In general, anvil-level air parcels contained an estimated 20 - 40% boundary layer air in the analyzed storms. C1 Bay Area Environm Res Inst, Sonoma, CA 95476 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Natl Ctr Atmospher Res, Boulder, CO 80303 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lopez, JP (reprint author), Bay Area Environm Res Inst, Sonoma, CA 95476 USA. EM jlopez@mail.arc.nasa.gov RI Davis, Sean/C-9570-2011; Ackerman, Andrew/D-4433-2012; Fridlind, Ann/E-1495-2012; Herman, Robert/H-9389-2012; Hallar, Anna Gannet/I-9104-2012 OI Davis, Sean/0000-0001-9276-6158; Ackerman, Andrew/0000-0003-0254-6253; Herman, Robert/0000-0001-7063-6424; Hallar, Anna Gannet/0000-0001-9972-0056 NR 61 TC 7 Z9 8 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 6 PY 2006 VL 111 IS D9 AR D09305 DI 10.1029/2005JD006104 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 041ID UT WOS:000237447100002 ER PT J AU Barwick, SW Beatty, JJ Besson, DZ Binns, WR Cai, B Clem, JM Connolly, A Cowen, DF Dowkontt, PF DuVernois, MA Evenson, PA Goldstein, D Gorham, PW Hebert, CL Israel, MH Learned, JG Liewer, KM Link, JT Matsuno, S Miocinovic, P Nam, J Naudet, CJ Nichol, R Palladino, K Rosen, M Saltzberg, D Seckel, D Silvestri, A Stokes, BT Varner, GS Wu, F AF Barwick, SW Beatty, JJ Besson, DZ Binns, WR Cai, B Clem, JM Connolly, A Cowen, DF Dowkontt, PF DuVernois, MA Evenson, PA Goldstein, D Gorham, PW Hebert, CL Israel, MH Learned, JG Liewer, KM Link, JT Matsuno, S Miocinovic, P Nam, J Naudet, CJ Nichol, R Palladino, K Rosen, M Saltzberg, D Seckel, D Silvestri, A Stokes, BT Varner, GS Wu, F TI Constraints on cosmic neutrino fluxes from the Antarctic Impulsive Transient Antenna experiment SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-ENERGY NEUTRINOS; COHERENT RADIO EMISSION; ULTRAHIGH ENERGY; RAYS; CASCADES; SPECTRUM; SHOWERS; CHARGE; LIMITS; AIR AB We report new limits on cosmic neutrino fluxes from the test flight of the Antarctic Impulsive Transient Antenna (ANITA) experiment, which completed an 18.4 day flight of a prototype long-duration balloon payload, called ANITA-lite, in early 2004. We search for impulsive events that could be associated with ultrahigh energy neutrino interactions in the ice and derive limits that constrain several models for ultrahigh energy neutrino fluxes and rule out the long-standing Z-burst model. C1 Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. Washington Univ, Dept Phys, St Louis, MO 63130 USA. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Delaware, Bartol Res Inst, Newark, DE USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Hawaii Manoa, Dept Phys & Astron, Honolulu, HI 96822 USA. Jet Propuls Lab, Pasadena, CA USA. RP Barwick, SW (reprint author), Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. RI Nichol, Ryan/C-1645-2008; Connolly, Amy/J-3958-2013; Beatty, James/D-9310-2011 OI Beatty, James/0000-0003-0481-4952 NR 36 TC 136 Z9 136 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 5 PY 2006 VL 96 IS 17 AR 171101 DI 10.1103/PhysRevLett.96.171101 PG 4 WC Physics, Multidisciplinary SC Physics GA 039QO UT WOS:000237321500005 PM 16712284 ER PT J AU Lorenz, RD Wall, S Radebaugh, J Boubin, G Reffet, E Janssen, M Stofan, E Lopes, R Kirk, R Elachi, C Lunine, J Mitchell, K Paganelli, F Soderblom, L Wood, C Wye, L Zebker, H Anderson, Y Ostro, S Allison, M Boehmer, R Callahan, P Encrenaz, P Ori, GG Francescetti, G Gim, Y Hamilton, G Hensley, S Johnson, W Kelleher, K Muhleman, D Picardi, G Posa, F Roth, L Seu, R Shaffer, S Stiles, B Vetrella, S Flamini, E West, R AF Lorenz, RD Wall, S Radebaugh, J Boubin, G Reffet, E Janssen, M Stofan, E Lopes, R Kirk, R Elachi, C Lunine, J Mitchell, K Paganelli, F Soderblom, L Wood, C Wye, L Zebker, H Anderson, Y Ostro, S Allison, M Boehmer, R Callahan, P Encrenaz, P Ori, GG Francescetti, G Gim, Y Hamilton, G Hensley, S Johnson, W Kelleher, K Muhleman, D Picardi, G Posa, F Roth, L Seu, R Shaffer, S Stiles, B Vetrella, S Flamini, E West, R TI The sand seas of Titan: Cassini RADAR observations of longitudinal dunes SO SCIENCE LA English DT Article ID SURFACE; WINDS AB The most recent Cassini RADAR images of Titan show widespread regions ( up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show similar to 100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of similar to 0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps. C1 Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. US Geol Survey, Flagstaff, AZ 86001 USA. Proxemy Res, Bowie, MD 20715 USA. Planetary Sci Inst, Tucson, AZ 85719 USA. Wheeling Jesuit Coll, Wheeling, WV 26003 USA. Stanford Univ, Stanford, CA 94305 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Observ Paris, F-92195 Meudon, France. Univ G DAnnunzio, Int Res Sch Planetary Sci, I-65127 Pescara, Italy. Fac Ingn, I-80125 Naples, Italy. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. Univ Roma La Sapienza, I-00184 Rome, Italy. Politecn Bari, Dipartimento Interateneo Fis, I-70126 Bari, Italy. INFM, I-70126 Bari, Italy. Agenzia Spaziale Italiana, I-00131 Rome, Italy. RP Lorenz, RD (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. EM rlorenz@lpl.arizona.edu RI Lorenz, Ralph/B-8759-2016; Lopes, Rosaly/D-1608-2016; OI Lorenz, Ralph/0000-0001-8528-4644; Lopes, Rosaly/0000-0002-7928-3167; ORI, Gian Gabriele/0000-0002-6460-1476 NR 27 TC 194 Z9 199 U1 3 U2 23 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAY 5 PY 2006 VL 312 IS 5774 BP 724 EP 727 DI 10.1126/science.1123257 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 039NF UT WOS:000237312100044 PM 16675695 ER PT J AU Lohmann, U Koren, I Kaufman, YJ AF Lohmann, U Koren, I Kaufman, YJ TI Disentangling the role of microphysical and dynamical effects in determining cloud properties over the Atlantic SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GENERAL-CIRCULATION MODEL; OPTICAL-PROPERTIES; AEROSOL; NUMBER; GCM AB MODIS satellite data reveal that over the Atlantic Ocean ( 20 degrees S - 30 degrees N) in June - August 2002 indirect aerosol effects cause a decrease in the cloud top effective radius of stratiform clouds of 2.9 mu m and an increase in cloud fraction of 21%, when increasing the aerosol optical thickness (AOT) from the cleanest 5 percentile to an AOT of 0.2. Thus, indirect aerosol effects are responsible for 72% (- 8.8 W m(-2)) of the - 12.2 W m(-2) decrease in the shortwave radiation at the top-of-the atmosphere (TOA). Global climate model simulations with and without indirect aerosol effects confirm a decrease in TOA shortwave cloud forcing of - 9 W m(-2) over the Atlantic from the cleanest to the highest AOT due to indirect aerosol effects. While MODIS shows an increase in cloud fraction due to aerosols, in the model aerosols cause primarily an increase in cloud water. Thus, unlike the analysis from MODIS, the increase in cloud fraction with increasing AOT is dominated by changes in dynamical regimes, not by aerosol indirect effects. C1 ETH, Inst Atmospher & Climate Sci, CH-8092 Zurich, Switzerland. Weizmann Inst Sci, Dept Environm Sci, IL-76100 Rehovot, Israel. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lohmann, U (reprint author), ETH, Inst Atmospher & Climate Sci, CH-8092 Zurich, Switzerland. EM ulrike.lohmann@env.ethz.ch RI Koren, Ilan/K-1417-2012; Lohmann, Ulrike/B-6153-2009 OI Koren, Ilan/0000-0001-6759-6265; Lohmann, Ulrike/0000-0001-8885-3785 NR 18 TC 16 Z9 16 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 4 PY 2006 VL 33 IS 9 AR L09802 DI 10.1029/2005GL024625 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 041HV UT WOS:000237446300002 ER PT J AU Giampieri, G Dougherty, MK Smith, EJ Russell, CT AF Giampieri, G Dougherty, MK Smith, EJ Russell, CT TI A regular period for Saturn's magnetic field that may track its internal rotation SO NATURE LA English DT Article ID MAGNETOSPHERE; VOYAGER-1; RADIO; ORBIT AB The rotation rate of a planet is one of its fundamental properties. Saturn's rotation, however, is difficult to determine because there is no solid surface from which to time it, and the alternative 'clock'-the magnetic field-is nearly symmetrically aligned with the rotation axis(1-7). Radio emissions, thought to provide a proxy measure of the rotation of the magnetic field, have yielded estimates of the rotation period between 10 h 39 min 22 s and 10 h 45 min 45 s (refs 8-10). Because the period determined from radio measurements exhibits large time variations, even on time-scales of months, it has been uncertain whether the radio-emission periodicity coincides with the inner rotation rate of the planet. Here we report magnetic field measurements that revealed a time-stationary magnetic signal with a period of 10 h 47 min 6 s +/-40 s. The signal appears to be stable in period, amplitude and phase over 14 months of observations, pointing to a close connection with the conductive region inside the planet, although its interpretation as the 'true' inner rotation period is still uncertain. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2AZ, England. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90025 USA. RP Giampieri, G (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM giacomo.giampieri@jpl.nasa.gov OI Russell, Christopher/0000-0003-1639-8298 NR 21 TC 82 Z9 82 U1 0 U2 3 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 4 PY 2006 VL 441 IS 7089 BP 62 EP 64 DI 10.1038/nature04750 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 038TB UT WOS:000237248600031 PM 16672964 ER PT J AU Platts, SH Shi, SJ Meck, JV AF Platts, SH Shi, SJ Meck, JV TI Akathisia with combined use of midodrine and promethazine SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Letter ID HUMAN LIVER-MICROSOMES; METABOLISM C1 Univ Space Res Assoc, Columbia, MD 21044 USA. Wyle Labs, El Segundo, CA 90245 USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. RP Platts, SH (reprint author), Univ Space Res Assoc, Columbia, MD 21044 USA. EM jmeck@ems.jsc.nasa.gov NR 6 TC 4 Z9 4 U1 1 U2 1 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610-0946 USA SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD MAY 3 PY 2006 VL 295 IS 17 BP 2000 EP 2001 DI 10.1001/jama.295.17.2000-b PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 038MF UT WOS:000237225100015 PM 16670408 ER PT J AU Hocke, K Kampfer, N Feist, DG Calisesi, Y Jiang, JH Chabrillat, S AF Hocke, K Kampfer, N Feist, DG Calisesi, Y Jiang, JH Chabrillat, S TI Temporal variance of lower mesospheric ozone over Switzerland during winter 2000/2001 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The Stratospheric Ozone Monitoring Radiometer (SOMORA) is continuously operated in Switzerland and measures ozone volume mixing ratio q(O3) in the stratosphere and lower mesosphere with a time resolution of about 30 min. Temporal variances S ( wave period band 1 - 3 h) of daytime and nighttime ozone are studied at an altitude of 55 km from October 1, 2000 to May 1, 2001. Gravity waves are assumed as cause of the observed short-time fluctuations of q(O3). Strong negative and positive correlations are found between the dynamic state of the stratosphere ( represented by time series of ERA-40 reanalyses) and SOMORA's S and q(O3) series of lower mesospheric ozone. Oscillations with periods of 5-30 days are present in the S and q(O3) series. C1 Univ Bern, Inst Appl Phys, CH-3012 Bern, Switzerland. Int Space Sci Inst, CH-3012 Bern, Switzerland. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Meteorol Serv Canada, Dorval, PQ H9P 1J3, Canada. RP Hocke, K (reprint author), Univ Bern, Inst Appl Phys, Sidlerstr 5, CH-3012 Bern, Switzerland. EM klemens.hocke@mw.iap.unibe.ch RI Feist, Dietrich/B-6489-2013 OI Feist, Dietrich/0000-0002-5890-6687 NR 8 TC 5 Z9 5 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 2 PY 2006 VL 33 IS 9 AR L09801 DI 10.1029/2005GL025496 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 041HT UT WOS:000237446100001 ER PT J AU Fernandez, JM Gomez, ARP Cancapa, JJQ de Arellano Lopez, AR Llorca, J AF Martinez Fernandez, J. Pinto Gomez, A. R. Quispe Cancapa, J. J. de Arellano Lopez, A. R. Llorca, J. TI High-temperature plastic deformation of Er2O3-doped ZrO2 single crystals SO ACTA MATERIALIA LA English DT Article DE plastic deformation; zirconia; high-temperature mechanical properties; dislocations; scanning/transmission electron microscopy ID YTTRIA-STABILIZED ZIRCONIA; MECHANICAL-PROPERTIES; MICROSTRUCTURE AB The high-temperature plastic deformation of 5 mol% Er2O3-doped ZrO2 monofilaments and rods processed by the laser-heated floating-zone method was studied using tensile and compression tests. The microstructure of the as-fabricated and plastically deformed crystals was characterized by scanning and transmission electron microscopy. The crystals were formed by a fine distribution of nano-meter-sized tetragonal variants with the c-axes mutually perpendicular, this particular microstructure being a consequence of the fast quenching associated with the fabrication process. A model is proposed to analyze the interaction between dislocations gliding in the multiple {100} (011) slip planes and the interaction of dislocations with the tetragonal variants, taking into account the peculiar microstructure of the material. The model explains the high work hardening observed in the system, the formation of unique plasticity-induced defects, and the high-temperature fracture mechanisms. These issues are discussed in comparison with previous studies of yttria-doped partially stabilized zirconia. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 Univ Seville, Dept Condensed Matter Phys, ICMSE, CSIC, Seville 41080, Spain. Univ Politecn Madrid, Dept Mat Sci, ETS Ingn Caminos, E-28040 Madrid, Spain. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Fernandez, JM (reprint author), Univ Seville, Dept Condensed Matter Phys, ICMSE, CSIC, POB 1065, Seville 41080, Spain. EM martinez@us.es RI LLorca, Javier/C-1140-2013; OI LLorca, Javier/0000-0002-3122-7879; R. de Arellano Lopez, Antonio/0000-0002-7443-0244 NR 19 TC 1 Z9 1 U1 0 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAY PY 2006 VL 54 IS 8 BP 2195 EP 2204 DI 10.1016/j.actamat.2006.01.012 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 043KR UT WOS:000237600400020 ER PT J AU Munson, JC Nikora, AP Sherif, JS AF Munson, JC Nikora, AP Sherif, JS TI Software faults: A quantifiable definition SO ADVANCES IN ENGINEERING SOFTWARE LA English DT Review DE software faults; defect detection; software quality ID MULTIPLE PROCESSOR SYSTEMS; CONCURRENT ERROR-DETECTION; INSPECTION METHOD; RELIABILITY; EXPERIENCE; PROGRAMS; LESSONS; METRICS AB An important aspect of developing models relating the number and type of faults in a software system to a set of structural measurement is defining what constitutes a fault. By definition, a fault is a structural imperfection in a software system that may lead to the system's eventually failing. A measurable and precise definition of what faults are makes it possible to accurately identify and count them, which in turn allows the formulation of models relating fault counts and types to other measurable attributes of a software system. Unfortunately, the most widely used definitions are not measurable-there is no guarantee that two different individuals looking at the same set of failure reports and the same set of fault definitions will count the same number of underlying faults. The incomplete and ambiguous nature of current fault definitions adds a noise component to the inputs used in modeling fault content. If this noise component is sufficiently large, any attempt to develop a fault model will produce invalid results. In this paper, we base our recognition and enumeration of software faults on the grammar of the language of the software system. By tokenizing the differences between a version of the system exhibiting a particular failure behavior, and the version in which changes were made to eliminate that behavior, we are able to unambiguously count the number of faults associated with that failure. With modern configuration management tools, the identification and counting of software faults can be automated. (C) 2005 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Idaho, Dept Comp Sci, Moscow, ID 83844 USA. Calif State Univ Fullerton, Fullerton, CA 92834 USA. RP Sherif, JS (reprint author), CALTECH, Jet Prop Lab, Mail Stop 126-201,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rolf.hanitsch@iee.tu-berlin.de NR 134 TC 5 Z9 9 U1 0 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0965-9978 J9 ADV ENG SOFTW JI Adv. Eng. Softw. PD MAY PY 2006 VL 37 IS 5 BP 327 EP 333 DI 10.1016/j.advengsoft.2005.07.003 PG 7 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Engineering, Multidisciplinary SC Computer Science; Engineering GA 022KL UT WOS:000236054600004 ER PT J AU Nielsen, EJ Park, MA AF Nielsen, Eric J. Park, Michael A. TI Using an adjoint approach to eliminate mesh sensitivities in computational design SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 43rd Aerospace Sciences Meeting and Exhibit CY JAN 10-13, 2005 CL Reno, NV SP AIAA ID UNSTRUCTURED GRIDS; TURBULENT FLOWS; OPTIMIZATION; FORMULATION; ALGORITHM; EQUATIONS AB An adjoint algorithm for efficiently incorporating the effects of mesh sensitivities in a computational design framework is introduced. The method eliminates the need for explicit linearizations of the mesh movement scheme with respect to the geometric parameterization variables, an expense that has hindered large-scale design optimization for practical applications. The effects of the mesh sensitivities can be accounted for through the solution of an adjoint problem equivalent in cost to a single mesh movement computation, followed by an explicit matrix-vector product whose cost scales with the number of design variables and the resolution of the parameterized surface grid. The methodology augments the current practice of using adjoints solely for the flowfield and leads to a dramatic computational savings. The accuracy of the implementation is established, and several sample design optimizations are shown. C1 NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. RP Nielsen, EJ (reprint author), NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Mail Stop 128, Hampton, VA 23681 USA. NR 49 TC 25 Z9 25 U1 1 U2 1 PU AMER INST AERONAUTICS ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 EI 1533-385X J9 AIAA J JI AIAA J. PD MAY PY 2006 VL 44 IS 5 BP 948 EP 953 DI 10.2514/1.16052 PG 6 WC Engineering, Aerospace SC Engineering GA 041YB UT WOS:000237492000003 ER PT J AU Liu, TS Kuykendoll, K Rhew, R Jones, S AF Liu, TS Kuykendoll, K Rhew, R Jones, S TI Avian wing geometry and kinematics SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 24th Aerodynamic Measurement Technology and Ground Testing Conference CY JUN 28-JUL 01, 2004 CL Portland, OR SP AIAA AB The avian wing geometry of a seagull, merganser, teal, and owl extracted from noncontact surface measurements using a three-dimensional laser scanner is presented; The geometrical quantities, including the camber line and thickness distribution of the airfoil, wing planform, chord distribution, and twist distribution, are given in convenient analytical expressions. The avian wing kinematics is recovered from videos of a level-flying seagull, crane, and goose based on a two-jointed arm model in which three characteristic angles are expressed in the Fourier series as a function of time. Therefore, the flapping avian wing with the correct kinematics can be computationally generated for the aerodynamic study of flapping flight. C1 Western Michigan Univ, Dept Mech & Aeronaut Engn, Kalamazoo, MI 49008 USA. NASA, Langley Res Ctr, Res Hardware Validat & Verificat Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Aeronaut Syst Engn Branch, Hampton, VA 23681 USA. RP Liu, TS (reprint author), Western Michigan Univ, Dept Mech & Aeronaut Engn, G-220, Kalamazoo, MI 49008 USA. EM tianshu.liu@wmich.edu NR 10 TC 31 Z9 35 U1 2 U2 12 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD MAY PY 2006 VL 44 IS 5 BP 954 EP 963 DI 10.2514/1.16224 PG 10 WC Engineering, Aerospace SC Engineering GA 041YB UT WOS:000237492000004 ER PT J AU Loh, CY Hultgren, LS AF Loh, CY Hultgren, LS TI Jet screech noise computation SO AIAA JOURNAL LA English DT Article ID TIME CONSERVATION ELEMENT; LARGE-EDDY SIMULATION; NUMERICAL-SIMULATION; LIP THICKNESS; GENERATION; TONES AB The near-field screech-tone noise of a typical underexpanded circular jet issuing from a sonic nozzle is simulated numerically. The self-sustained feedback loop is automatically established in the simulation. The computed shock-cell structure, acoustic wave length, screech-tone frequencies, and sound pressure levels in the near field are in good agreement with existing experimental results. C1 NASA, John H Glenn Res Ctr Lewis Field, Taitech Inc, Cleveland, OH 44135 USA. NASA, John H Glenn Res Ctr Lewis Field, Prop Syst Div, Cleveland, OH 44135 USA. RP Loh, CY (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Taitech Inc, Cleveland, OH 44135 USA. NR 29 TC 12 Z9 12 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD MAY PY 2006 VL 44 IS 5 BP 992 EP 998 DI 10.2514/1.4591 PG 7 WC Engineering, Aerospace SC Engineering GA 041YB UT WOS:000237492000008 ER PT J AU Turyshev, SG Anderson, JD Nieto, MM AF Turyshev, SG Anderson, JD Nieto, MM TI The pioneer spacecraft - Reply SO AMERICAN JOURNAL OF PHYSICS LA English DT Letter C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Turyshev, SG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC PHYSICS TEACHERS AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD MAY PY 2006 VL 74 IS 5 BP 373 EP 374 DI 10.1119/1.2167766 PG 2 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 040GJ UT WOS:000237366700004 ER PT J AU Snover, ML Watters, GM Mangel, M AF Snover, ML Watters, GM Mangel, M TI Top-down and bottom-up control of life-history strategies in coho salmon (Oncorhynchus kisutch) SO AMERICAN NATURALIST LA English DT Article DE reproductive fitness; freshwater; saltwater; genotype ID DWELLING ATLANTIC SALMON; PRINCE-WILLIAM SOUND; SOCKEYE-SALMON; CHINOOK SALMON; PACIFIC SALMON; MARINE GROWTH; FRESH-WATER; BODY-SIZE; BREEDING COMPETITION; MATING STRATEGIES AB Sexual maturation profoundly affects population dynamics, but the degrees to which genetic, top-down, and bottom-up controls affect age at maturity are unclear. Salmonid fishes have plastic age at maturity, and we consider genetic and environmental effects on this trait by developing fitness functions for coho salmon ( Oncorhynchus kisutch). The functions are based on size-specific survival and reproductive success, where reproductive success is the product of fecundity and ability to defend nests ( females) or the product of sperm volume and ability to mate ( males). We model genetic and bottom-up controls ( e. g., food availability) with an environmentally explicit growth function and top-down control ( predation mortality) with survival functions that consider both size-dependent and size-independent mortality. For females, we predict that early maturation rarely maximizes fitness, but males can maximize fitness by maturing early if they grow well in freshwater. We predict that early maturation is most affected by the bottom-up effects of resource distribution at sea, followed by bottom-up and genotypic effects in freshwater. Top-down processes are predicted to have strong effects on the likelihood of delayed maturation. C1 NOAA, Div Environm Res, Natl Marine Fisheries Serv, Pacific Grove, CA 93950 USA. Univ Hawaii, Joint Inst Marine & Atmospher Res, Honolulu, HI 96822 USA. Univ Calif Santa Cruz, Dept Appl Math & Stat, Ctr Stock Assessment Res, Santa Cruz, CA 95064 USA. RP Snover, ML (reprint author), NOAA, Pacific Isl Fisheries Sci Ctr, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. EM melissa.snover@noaa.gov; george.watters@noaa.gov; msmangel@soe.ucsc.edu NR 69 TC 12 Z9 12 U1 3 U2 18 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0003-0147 J9 AM NAT JI Am. Nat. PD MAY PY 2006 VL 167 IS 5 BP E140 EP E157 DI 10.1086/502804 PG 18 WC Ecology; Evolutionary Biology SC Environmental Sciences & Ecology; Evolutionary Biology GA 038GM UT WOS:000237207100018 PM 16671006 ER PT J AU Ley, RE Harris, JK Wilcox, J Spear, JR Miller, SR Bebout, BM Maresca, JA Bryant, DA Sogin, ML Pace, NR AF Ley, RE Harris, JK Wilcox, J Spear, JR Miller, SR Bebout, BM Maresca, JA Bryant, DA Sogin, ML Pace, NR TI Unexpected diversity and complexity of the Guerrero Negro hypersaline microbial mat SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SULFATE-REDUCING BACTERIA; RNA HYBRIDIZATION PROBES; GEN. NOV.; COMMUNITIES; STROMATOLITES; PROGRAM; BIOGEOCHEMISTRY; ENVIRONMENTS; ECOSYSTEMS; BIOMARKERS AB We applied nucleic acid-based molecular methods, combined with estimates of biomass (ATP), pigments, and microelectrode measurements of chemical gradients, to map microbial diversity vertically on a millimeter scale in a hypersaline microbial mat from Guerrero Negro, Baja California Sur, Mexico. To identify the constituents of the mat, small-subunit rRNA genes were amplified by PCR from community genomic DNA extracted from layers, cloned, and sequenced. Bacteria dominated the mat and displayed unexpected and unprecedented diversity. The majority (1,336) of the 1,586 bacterial 16S rRNA sequences generated were unique, representing 752 species (>= 97% rRNA sequence identity) in 42 of the main bacterial phyla, including 15 novel candidate phyla. The diversity of the mat samples differentiated according to the chemical milieu defined by concentrations of 0, and H,S. Bacteria of the phylum Chloroflexi formed the majority of the biomass by percentage of bulk rRNA and of clones in rRNA gene libraries. This result contradicts the general belief that cyanobacteria dominate these communities. Although cyanobacteria constituted a large fraction of the biomass in the upper few millimeters (> 80% of the total rRNA and photosynthetic pigments), Chloroflexi sequences were conspicuous throughout the mat. Filamentous Chloroflexi bacteria were identified by fluorescence in situ hybridization within the polysaccharide sheaths of the prominent cyanobacterium Microcoleus chthonoplastes, in addition to free living in the mat. The biological complexity of the mat far exceeds that observed in other polysaccharide-rich microbial ecosystems, such as the human and mouse distal guts, and suggests that positive feedbacks exist between chemical complexity and biological diversity. C1 Univ Colorado, Dept Mol Cellular & Dev Biol, Boulder, CO 80309 USA. Univ Colorado, Ctr Astrobiol, Boulder, CO 80309 USA. Univ Montana, Div Biol Sci, Missoula, MT 59812 USA. NASA Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. Penn State Univ, Dept Biochem & Mol Biol, University Pk, PA 16802 USA. Marine Biol Lab, Woods Hole, MA 02543 USA. RP Pace, NR (reprint author), Univ Colorado, Dept Mol Cellular & Dev Biol, Boulder, CO 80309 USA. EM nrpace@colorado.edu RI Ley, Ruth/M-8542-2014; OI Ley, Ruth/0000-0002-9087-1672; Spear, John/0000-0002-4664-7438; Maresca, Julia/0000-0002-3955-1585 NR 63 TC 235 Z9 240 U1 4 U2 87 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD MAY PY 2006 VL 72 IS 5 BP 3685 EP 3695 DI 10.1128/AEM.72.5.3685-3695.2006 PG 11 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 041XV UT WOS:000237491200074 PM 16672518 ER PT J AU Larochelle, KJ Morscher, GN AF Larochelle, K. J. Morscher, G. N. TI Tensile stress rupture behavior of a woven ceramic matrix composite in humid environments at intermediate temperature - Part I SO APPLIED COMPOSITE MATERIALS LA English DT Article DE ceramic matrix composites; silicon carbide; boron nitride; embrittlement; stress rupture; moisture; intermediate temperature; sylramic ID BORON-NITRIDE; OXIDATION; INTERFACES AB The stress rupture strength. of the SYL-iBN/BN/SiC composite was evaluated at 550 and 750 degrees C with moisture content levels of 0.0, 0.2, and 0.6 atm partial pressure of water vapor, pH(2)O. The stress rupture strengths decreased with respect to time with the rate of decrease related to the temperature and the amount of moisture content. In all cases the degradation was more severe initially and then approached a run-out threshold level. The thresholds were reached at approximately 100+, 60, 80 h for the 550 degrees C with 0.0, 0.2, and 0.6 pH(2)O, respectively. The thresholds were reached at approximately 40, 20, and 10 h for the 750 degrees C cases. The interpolated stress rupture strengths at 100 h for 0.0, 0.2, and 0.6 pH(2)O at 550 degrees C were 82%, 68%, and 51% of the room temperature monotonic tensile strength. At 750 degrees C these strengths were 67%, 51%, and 50%. Analysis of Field Emission Scanning Electron Microscopy images showed evidence of embrittlement of the fiber/matrix interphase. Little to no embrittlement was observed at both temperatures with 0.0 pH(2)O. At both 550 and 750 degrees C with 0.2 and 0.6 pH(2)O, evidence of embrittlement increased with temperature and test duration with the most extensive embrittlement observed at 750 degrees C with 0.6 pH(2)O. C1 European Off Aerosp Res & Dev, London NW1 5TH, England. NASA, Ohio Aerosp Inst, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Larochelle, KJ (reprint author), European Off Aerosp Res & Dev, 223-231 Old Marylebone Rd, London NW1 5TH, England. EM kevin@larochelle.demon.co.uk NR 18 TC 5 Z9 5 U1 0 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-189X J9 APPL COMPOS MATER JI Appl. Compos. Mater. PD MAY PY 2006 VL 13 IS 3 BP 147 EP 172 DI 10.1007/s10443-006-9009-8 PG 26 WC Materials Science, Composites SC Materials Science GA 074VO UT WOS:000239840100002 ER PT J AU O'Brien, TK Krueger, R AF O'Brien, T. Kevin Krueger, Ronald TI Influence of compression and shear on the strength of composite laminates with z-pinned reinforcement SO APPLIED COMPOSITE MATERIALS LA English DT Article DE z-pin; compression strength; shear; laminates ID FIBER COMPOSITES AB The influence of compression and shear loads on the strength of composite laminates with z-pins is evaluated parametrically using a 2D Finite Element Code (FLASH) based on Cosserat couple stress theory. Meshes were generated for three unique combinations of z-pin diameter and density. A laminated plate theory analysis was performed on several layups to determine the bi-axial stresses in the zero degree plies. These stresses, in turn, were used to determine the magnitude of the relative load steps prescribed in the FLASH analyses. Results indicated that increasing pin density was more detrimental to in-plane compression strength than increasing pin diameter. Compression strengths of lamina without z-pins agreed well with a closed form expression derived by Budiansky and Fleck. FLASH results for lamina with z-pins were consistent with the closed form results, and FLASH results without z-pins, if the initial fiber waviness due to z-pin insertion was added to the fiber waviness in the material to yield a total misalignment. Addition of 10% shear to the compression loading significantly reduced the lamina strength compared to pure compression loading. Addition of 50% shear to the compression indicated shear yielding rather than kink band formation as the likely failure mode. Two different stiffener reinforced skin configurations with z-pins, one quasi-isotropic and one orthotropic, were also analyzed. Six unique loading cases ranging from pure compression to compression plus 50% shear were analyzed assuming material fiber waviness misalignment angles of 0, 1, and 2 degrees. Compression strength decreased with increased shear loading for both configurations, with the quasi-isotropic configuration yielding lower strengths than the orthotropic configuration. C1 NASA, Langley Res Ctr, USA Res Lab, Hampton, VA 23681 USA. Natl Inst Aerosp, Hampton, VA 23681 USA. RP O'Brien, TK (reprint author), NASA, Langley Res Ctr, USA Res Lab, Hampton, VA 23681 USA. EM thomas.k.obrien@nasa.gov RI Krueger, Ronald/G-5356-2015 NR 12 TC 22 Z9 24 U1 0 U2 11 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-189X J9 APPL COMPOS MATER JI Appl. Compos. Mater. PD MAY PY 2006 VL 13 IS 3 BP 173 EP 189 DI 10.1007/s10443-005-9005-4 PG 17 WC Materials Science, Composites SC Materials Science GA 074VO UT WOS:000239840100003 ER PT J AU Kondrachuk, AV Boyle, RD AF Kondrachuk, AV Boyle, RD TI Feedback hypothesis and the effects of altered gravity on formation and function of gravireceptors of mollusks and fish SO ARCHIVES ITALIENNES DE BIOLOGIE LA English DT Article; Proceedings Paper CT Joint Life Science Conference of the European-Space-Agency/International-Society-of-Gravitational-Physiology CY JUN 26-JUL 01, 2005 CL Cologne, GERMANY SP European Space Agcy, Int Soc Gravitat Phys ID INNER-EAR OTOLITHS; APLYSIA-CALIFORNICA; CRITICAL PERIOD; STATOCYST; HYPERGRAVITY; ZEBRAFISH; STATOCONIA; GROWTH; SPACE AB Popular hypothesis based on the idea of simple feedback mechanism that correlates gravity level and weight of test mass cannot explain the variety of the effects of altered gravity on development and function of gravireceptors. The reaction of organisms to the change of gravity depends on the gravisensitivity of the physical and chemical processes corresponding to specific phases of development and may have no relation to any feedback mechanisms of compensation of altered weight of the test mass. The present work analyzes the hypothesis of feedback and shows the ambiguity of possible effects of the altered gravity on formation and function of gravireceptors basing on the data from mollusks and fish. C1 NASA, Ames Res Ctr, BioVis Technol Ctr, Moffett Field, CA 94035 USA. Natl Acad Sci, Inst Phys, UA-03028 Kiev, Ukraine. NASA, Ames Res Ctr, Vestibular Res Facil, Moffett Field, CA 94035 USA. RP Boyle, RD (reprint author), NASA, Ames Res Ctr, BioVis Technol Ctr, M-S 239-11, Moffett Field, CA 94035 USA. EM kondr@kondr.kiev.ua; richard.boyle@nasa.gov NR 24 TC 4 Z9 4 U1 0 U2 3 PU UNIV PISA PI PISA PA LUNGARNO A PACINOTTI 43, 56100 PISA, ITALY SN 0003-9829 J9 ARCH ITAL BIOL JI Arch. Ital. Biol. PD MAY PY 2006 VL 144 IS 2 BP 75 EP 87 PG 13 WC Neurosciences SC Neurosciences & Neurology GA 033AE UT WOS:000236817500002 PM 16642787 ER PT J AU Lehmer, BD Brandt, WN Hornschemeier, AE Alexander, DM Bauer, FE Koekemoer, AM Schneider, DP Steffen, AT AF Lehmer, BD Brandt, WN Hornschemeier, AE Alexander, DM Bauer, FE Koekemoer, AM Schneider, DP Steffen, AT TI The properties and redshift evolution of intermediate-luminosity off-nuclear X-ray sources in the Chandra Deep Fields SO ASTRONOMICAL JOURNAL LA English DT Article DE cosmology : observations; diffuse radiation; surveys; X-rays : galaxies; X-rays : general ID STAR-FORMING GALAXIES; POINT-SOURCE CATALOGS; MASS BLACK-HOLES; NEARBY GALAXIES; PHOTOMETRIC REDSHIFTS; NORTH SURVEY; SOUTH; STELLAR; OBJECTS AB We analyze a population of intermediate-redshift (z approximate to 0.05-0.3) off-nuclear X-ray sources located within optically bright galaxies in the Great Observatories Origins Deep Survey and Galaxy Evolution from Morphology and SEDs fields. A total of 24 off-nuclear source candidates are classified using deep Chandra X-Ray Observatory exposures from the Chandra Deep Field-North, Chandra Deep Field-South, and Extended Chandra Deep Field-South; 15 of these are newly identified. These sources have average X-ray spectral shapes and optical environments similar to those observed for off-nuclear intermediate-luminosity (L(X) >= 10(39) ergs s(-1) in the 0.5-2.0 keV band) X-ray objects (IXOs; sometimes referred to as ultraluminous X-ray sources) in the local universe. This sample improves the available source statistics for intermediate-redshift off-nuclear sources with L(X) greater than or similar to 10(39.5) ergs s(-1), and it places significant new constraints on the redshift evolution of the off-nuclear source frequency in field galaxies. The fraction of intermediate-redshift field galaxies containing an off-nuclear source with L(X) greater than or similar to 10(39) ergs s(-1) is suggestively elevated (approximate to 80% confidence level) with respect to that observed for IXOs in the local universe; we calculate this elevation to be a factor of approximate to 1.9(-1.3)(+1.4). A rise in this fraction is plausibly expected as a consequence of the observed increase in global star formation density with redshift, and our results are consistent with the expected magnitude of the rise in this fraction. C1 Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. NASA, Goddard Space Flight Ctr, Lab XRay Astrophys, Greenbelt, MD 20771 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Columbia Univ, Pupin Labs, Columbia Astrophys Lab, New York, NY 10027 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Lehmer, BD (reprint author), Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. RI Brandt, William/N-2844-2015; OI Brandt, William/0000-0002-0167-2453; Alexander, David/0000-0002-5896-6313; Koekemoer, Anton/0000-0002-6610-2048 NR 47 TC 23 Z9 23 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2006 VL 131 IS 5 BP 2394 EP 2405 DI 10.1086/503107 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 037KY UT WOS:000237146900004 ER PT J AU Miller, NA Oegerle, WR Hill, JM AF Miller, NA Oegerle, WR Hill, JM TI Abell 2111: An optical and radio study of the richest Butcher-Oemler cluster SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : clusters : individual ( Abell 2111); galaxies : evolution; radio continuum : galaxies ID DIGITAL SKY SURVEY; SPECTROSCOPIC TARGET SELECTION; DATA REDUCTION TECHNIQUES; STAR-FORMATION; DISTANT CLUSTERS; MODERATE-REDSHIFT; GALAXY SAMPLE; EVOLUTION; EMISSION; MERGER AB We present an in-depth analysis of the Butcher-Oemler cluster A2111, including new optical spectroscopy plus a deep Very Large Array (VLA) radio continuum observation. These are combined with optical imaging from the Sloan Digital Sky Survey ( SDSS) to assess the activity and properties of member galaxies. Prior X-ray studies have suggested A2111 to be a head-on cluster merger, a dynamical state that might be connected to the high level of activity inferred from its blue fraction. We are able to directly assess this claim, using our spectroscopic data to identify 95 cluster members among 196 total galaxy spectra. These galaxy velocities do not themselves provide significant evidence for the merger interpretation; however, they are consistent with it provided that the system is viewed near the time of core passage and at a viewing angle greater than or similar to 30 degrees from the merger axis. The SDSS data allow us to confirm the high blue fraction for A2111, f(b) 0.15 +/- 0.03 based on photometry alone and f(b) 0.23 +/- 0.03 using spectroscopic data to remove background galaxies. We are able to detect 175 optical sources from the SDSS in our VLA radio data, of which 35 have redshift information. We use the SDSS photometry to determine photometric redshifts for the remaining 140 radio-optical sources. In total we identify up to 26 cluster radio galaxies, 14 of which have spectroscopic redshifts. The optical spectroscopy and radio data reveal a substantial population of dusty starbursts within the cluster. The high blue fraction and prevalence of star formation are consistent with the hypothesis that dynamically active clusters are associated with more active member galaxies than relaxed clusters. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. Large Binocular Telescope Observ, Tucson, AZ 85721 USA. RI Oegerle, William/C-9070-2012 NR 50 TC 13 Z9 14 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2006 VL 131 IS 5 BP 2426 EP 2441 DI 10.1086/503254 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 037KY UT WOS:000237146900007 ER PT J AU Howell, JH AF Howell, JH TI Star formation histories of nearby elliptical galaxies. II. Merger remnant sample SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : abundances; galaxies : elliptical and lenticular, cD; galaxies : evolution; galaxies : formation; galaxies : general; galaxies : interactions; galaxies : stellar content ID STELLAR POPULATION-MODELS; ABUNDANCE RATIOS; FINE-STRUCTURE; EVOLUTION; HYDROGEN; METALLICITIES; SPECTROSCOPY; GRADIENTS; NGC-1052; INDEXES AB This work presents high signal-to-noise spectroscopic observations of a sample of six suspected merger remnants, selected primarily on the basis of H I tidal debris detections. Single stellar population analysis of these galaxies indicates that their ages, metallicities, and alpha-enhancement ratios are consistent with those of a representative sample of nearby elliptical galaxies. The expected stellar population of a recent merger remnant, a young age combined with low [alpha/Fe], is not seen in any H I-selected galaxy. However, one galaxy (NGC 2534) is found to deviate from the Z-plane in the sense expected for a merger remnant. Another galaxy (NGC 7332), selected by other criteria, best matches the merger remnant expectations. C1 Univ Calif Santa Cruz, Dept Astron & Astrophys, UCO, Lick Observ, Santa Cruz, CA 95064 USA. RP Howell, JH (reprint author), CALTECH, Ctr Infrared Proc & Anal, Jet Prop Lab, MS 100-22, Pasadena, CA 91125 USA. EM jhhowell@ucolick.org NR 34 TC 2 Z9 2 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2006 VL 131 IS 5 BP 2469 EP 2477 DI 10.1086/503103 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 037KY UT WOS:000237146900010 ER PT J AU De Marco, O O'Dell, CR Gelfond, P Rubin, RH Glover, SCO AF De Marco, O O'Dell, CR Gelfond, P Rubin, RH Glover, SCO TI Cloud fragmentation and proplyd-like features in HII regions imaged by the Hubble Space Telescope SO ASTRONOMICAL JOURNAL LA English DT Article DE HII regions; planetary systems : protoplanetary disks; stars : formation; surveys ID INFRARED STAR-CLUSTERS; SOUTHERN MILKY-WAY; ORION-NEBULA; THACKERAYS GLOBULES; MOLECULAR CLOUD; STELLAR OBJECTS; OB STARS; NGC 6611; PHOTOMETRY; DISKS AB We have analyzed Hubble Space Telescope ACS and WFPC2 new and archival images of eight H II regions to look for new protoplanetary disks (proplyds) similar to those found in the Orion Nebula. We find a wealth of features similar in size ( although many are larger) to the bright cusps around the Orion Nebula proplyds. None of them, however, contains a definitive central star. From this, we deduce that the new cusps may not be proplyds but instead fragments of molecular cloud material. Out of all the features found in the eight H II regions examined, only one, an apparent edge-on silhouette in M17, may have a central star. This feature might join the small number of bona fide proplyds found outside the Orion Nebula, in M8, M20, and possibly M16. In line with the results found recently by Smith et al., the paucity of proplyds outside the Orion Nebula can be explained by their transient nature, as well as by the specific environmental conditions under which they can be observed. Several fragments are seen as dark silhouettes against a bright background. We have reanalyzed those found in IC 2944 by Reipurth et al. and found new, similar ones in M16. None of these fragments contains a central star, and we exclude the possibility that they are disks. Reipurth et al. concluded that the IC 2944 silhouettes are not star forming. We argue here that their assumption of a constant optical depth for these fragments is not physical and that it is more likely that these fragments are star forming, a condition that is supported, although not proved, by their shapes and distributions. The process of cloud fragmentation and photoevaporation produces a large number of small fragments, while the size hierarchy expected in a photoevaporative environment would not favor small fragments. The size distributions observed will constrain any future theories of cloud fragmentation. One bright microjet candidate is found in M17, protruding from a large, limb-brightened fragment. A second, larger, jetlike feature, similar in shape and size to a Herbig-Haro jet, is found in Pismis 24. No central star appears to be associated with either of these jet candidates. C1 Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Yale Univ, Dept Phys, New Haven, CT 06511 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Or Enterprises, Stanford, CA 94305 USA. RP De Marco, O (reprint author), Amer Museum Nat Hist, Dept Astrophys, Cent Pk W 79th St, New York, NY 10024 USA. EM orsola@amnh.org; cr.odell@vanderbilt.edu; pamela.gelfond@yale.edu; rubin@cygnus.arc.nasa.gov NR 52 TC 21 Z9 21 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2006 VL 131 IS 5 BP 2580 EP 2600 DI 10.1086/501528 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 037KY UT WOS:000237146900020 ER PT J AU O'Linger, JC Cole, DM Ressler, ME Wolf-Chase, G AF O'Linger, JC Cole, DM Ressler, ME Wolf-Chase, G TI A mid-infrared study of the class 0 cluster in LDN 1448 SO ASTRONOMICAL JOURNAL LA English DT Article DE infrared : stars; ISM : individual (LDN 1448); methods : data analysis (mid-infrared imaging); stars : formation ID YOUNG STELLAR OBJECTS; MOLECULAR OUTFLOW; OPHIUCHI CLOUD; PROTOSTARS; L1448; EVOLUTION; PERSEUS; BIPOLAR; IMAGES; STARS AB We present ground-based mid-infrared observations of Class 0 protostars in LDN 1448. Of the five known protostars in this cloud, we detected two, L1448N: A and L1448C, at 12.5, 17.9, 20.8, and 24.5 mu m, and a third, L1448 IRS 2, at 24.5 mu m. We present high-resolution images of the detected sources and photometry or upper limits for all five Class 0 sources in this cloud. With these data we are able to augment existing spectral energy distributions for all five objects and place them on an evolutionary status diagram. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Jet Propuls Lab, Pasadena, CA 91109 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP O'Linger, JC (reprint author), CALTECH, Spitzer Sci Ctr, MS 314-6, Pasadena, CA 91125 USA. EM joanno@ipac.caltech.edu; david.m.cole@jpl.nasa.gov; michael.e.ressler@jpl.nasa.gov; grace@horta.uchicago.edu NR 39 TC 12 Z9 12 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2006 VL 131 IS 5 BP 2601 EP 2608 DI 10.1086/500809 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 037KY UT WOS:000237146900021 ER PT J AU Marcillac, D Elbaz, D Chary, RR Dickinson, M Galliano, F Morrison, G AF Marcillac, D Elbaz, D Chary, RR Dickinson, M Galliano, F Morrison, G TI Mid infrared properties of distant infrared luminous galaxies SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : evolution; infrared : galaxies; galaxies : starburst ID DEEP-FIELD-NORTH; SPECTRAL ENERGY-DISTRIBUTION; STAR-FORMATION RATE; REDSHIFT SURVEY; MIDINFRARED OBSERVATIONS; ISOCAM OBSERVATIONS; RADIO-EMISSION; SOURCE COUNTS; HDF-N; SPITZER AB We present evidence that the mid infrared (MIR, rest frame 5-30 mu m) is a good tracer of the total infrared luminosity, L(IR)(=L[8-1000 mu m]), and star formation rate (SFR), of galaxies up to z similar to 1.3. We use deep MIR images from the Infrared Space Observatory (ISO) and the Spitzer Space Telescope in the Northern field of the Great Observatories Origins Deep Survey (GOODS-N) together with VLA radio data to compute three independant estimates of L(IR). The L(IR, MIR) derived from the observed 15 and/or 24 mu m flux densities using a library of template SEDs, and L(IR, radio), derived from the radio (1.4 and/or 8.5 GHz) using the radio-far infrared correlation, agree with a 1-sigma dispersion of 40%. We use the k-correction as a tool to probe different parts of the MIR spectral energy distribution (SED) of galaxies as a function of their redshift and find that on average distant galaxies present MIR SEDs very similar to local ones. However, in the redshift range z = 0.4-1.2, L( IR, 24 mu m) is in better agreement with L(IR, radio) than L(IR, 15 mu m) by 20%, suggesting that the warm dust continuum is a better tracer of the SFR than the broad emission features due to polycyclic aromatic hydrocarbons (PAHs). We find marginal evidence for an evolution with redshift of the MIR SEDs: two thirds of the distant galaxies exhibit rest-frame MIR colors (L(12 mu m)/L(7 mu m) and L(10 mu m)/L(15 mu m) luminosity ratios) below the median value measured for local galaxies. Possible explanations are examined but these results are not sufficient to constrain the physics of the emitting regions. If confirmed through direct spectroscopy and if it gets amplified at higher redshifts, such an effect should be considered when deriving cosmic star formation histories of dust-obscured galaxies. We compare three commonly used SED libraries which reproduce the color-luminosity correlations of local galaxies with our data and discuss possible refinements to the relative intensities of PAHs, warm dust continuum and silicate absorption. C1 CEA Saclay, Serv Astrophys, DSM, DAPNIA, F-91191 Gif Sur Yvette, France. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 USA. Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA. Univ Hawaii, Inst Astron, Kamuela, HI 96743 USA. RP CEA Saclay, Serv Astrophys, DSM, DAPNIA, F-91191 Gif Sur Yvette, France. EM marcilla@discovery.saclay.cea.fr NR 62 TC 54 Z9 54 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 451 IS 1 BP 57 EP 69 DI 10.1051/0004-6361:20054035 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 036TB UT WOS:000237097200008 ER PT J AU Kundu, MR Schmahl, EJ Grigis, PC Garaimov, VI Shibasaki, K AF Kundu, MR Schmahl, EJ Grigis, PC Garaimov, VI Shibasaki, K TI Nobeyama radio heliograph observations of RHESSI microflares SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE flares; sun : photosphere; sun : X-rays, gamma rays; sun : corona ID HARD X-RAY; SOLAR ACTIVE REGIONS; TRANSIENT BRIGHTENINGS; EMISSION; FLARES; SPECTROMETER; YOHKOH AB Aims. We present a summary of the analysis of thirty microflares, observed simultaneously by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) in hard X-rays and by Nobeyama RadioHeliograph (NoRH) in microwaves ( 17 GHz). Methods. We used microflares observed by RHESSI in the energy range 3-25 keV, and for larger events, up to 35 keV. The observations were made 2002, May 2-6. Results. We describe the imaging characteristics of these microflares including their locations in hard X-rays and microwaves and the relative positions of the micro-flaring sources. We discuss the brightness temperatures, emission measures and their hard X-ray spectral properties. We see small ( mini) flaring loops clearly in NoRH and RHESSI images. The microwave emission often seems to come from the RHESSI foot points ( for higher energies), and from the entire small ( mini) flaring loop ( for lower energies). Sometimes the two ( microwave and hard X-ray) sources coincide, at other times they are at opposite ends of a mini flaring loop. Typically, the hard X-ray spectrum of the microwave associated RHESSI microflares can be fit by an isothermal component at low energies ( below 10 or 12 keV) and a nonthermal component at higher energies ( above 12 keV). Conclusions. Microflares in hard X-rays and in microwaves behave like normal flares in many respects. They can have both thermal and nonthermal components appearing in bremsstrahlung and gyrosynchrotron radiation. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. ETH, Inst Astron, CH-8092 Zurich, Switzerland. Special Astrophys Observ, St Petersburg, Russia. Nobeyama Radio Observ, Minamisa Ku, Nagano 38413, Japan. RP Kundu, MR (reprint author), Univ Maryland, Dept Astron, College Pk, MD 20742 USA. EM ed@astro.umd.edu NR 21 TC 10 Z9 10 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 451 IS 2 BP 691 EP 707 DI 10.1051/0004-6361:20053987 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 039AP UT WOS:000237272100029 ER PT J AU Dennerl, K Lisse, CM Bhardwaj, A Burwitz, V Englhauser, J Gunell, H Holmstrom, M Jansen, F Kharchenko, V Rodriguez-Pascual, PM AF Dennerl, K Lisse, CM Bhardwaj, A Burwitz, V Englhauser, J Gunell, H Holmstrom, M Jansen, F Kharchenko, V Rodriguez-Pascual, PM TI First observation of Mars with XMM-Newton - High resolution X-ray spectroscopy with RGS SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE atomic processes; molecular processes; solar wind; sun : X-rays, gamma rays; planets and satellites : individual : Mars; X-rays : individuals : Mars ID WIND CHARGE-EXCHANGE; SOLAR-WIND; PARAMETER-ESTIMATION; EMISSION; SPECTRA; VENUS; DISCOVERY; CHANDRA; HELIUM; COMETS AB In the first observation of Mars with XMM-Newton, on 20-21 November 2003, this planet is clearly detected as an X-ray source. High resolution X-ray spectroscopy with the Reflection Grating Spectrometer (RGS) confirms that the X-ray radiation from Mars is composed of two different components: one due to fluorescent scattering of solar X-rays in its upper atmosphere and the other one due to solar wind charge exchange in its exosphere. Close to Mars, the RGS spectrum is dominated by two pronounced CO2 fluorescence lines at 23.5 angstrom and 23.7 angstrom. Fluorescence from N-2 at 31.5 angstrom is also observed. With increasing distance from Mars, these lines fade, while numerous (similar to 12) emission lines become prominent at the positions expected for de-excitation of highly ionized C, N, O, and Ne atoms, strongly resembling a cometary X-ray spectrum. The He-like O6+ multiplet is resolved and is dominated by the spin-forbidden magnetic dipole transition 2 S-3(1) -> 1 S-1(0), confirming charge exchange as the origin of the emission, while the resonance line 2 P-1(1) -> 1 S-1(0) increases in intensity closer to Mars, where the density of the exosphere is higher. The high spectral dispersion and throughput of XMM-Newton / RGS make it possible to produce X- ray images of the Martian exosphere in individual emission lines, free from fluorescent radiation. They show extended emission out to similar to 8 Mars radii, with morphological differences between individual ions and ionization states. This is the first definite detection of charge exchange induced X-ray emission from the exosphere of another planet, providing a direct link to cometary X- ray emission. C1 Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. Swedish Inst Space Phys, S-98128 Kiruna, Sweden. European Space Agcy, Estec, NL-2200 AG Noordwijk, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. XMM Newton SOC, Madrid 28080, Spain. RP Dennerl, K (reprint author), Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. EM kod@mpe.mpg.de RI Gunell, Herbert/D-5611-2013; Lisse, Carey/B-7772-2016; OI Lisse, Carey/0000-0002-9548-1526; Gunell, Herbert/0000-0001-5379-1158; Bhardwaj, Anil/0000-0003-1693-453X NR 36 TC 56 Z9 56 U1 1 U2 3 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 451 IS 2 BP 709 EP 722 DI 10.1051/0004-6361:20054253 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 039AP UT WOS:000237272100030 ER PT J AU Stute, M AF Stute, M TI Hydrodynamical simulations of the jet in the symbiotic star MWC 560 - II. Simulations beyond density balance SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ISM : jets and outflows; binaries : symbiotic; line : profiles; hydrodynamics; methods : numerical ID R-AQUARII; SYSTEM AB Context. In the first paper of this series, we presented hydrodynamical simulations with radiative cooling of jet models with parameters representative of the symbiotic system MWC 560. These were jet simulations of a pulsed, initially underdense jet in a high-density ambient medium. They were stopped when the jet reached a length of 50 AU. There, however, a transition of the initially underdense jet towards an overdense jet should occur, which should result in changed kinematics. A few minor differences between the models and the observations were thought to be solved by a model with an increased jet density during the pulses which was calculated only with purely hydrodynamical means in the former paper. Aims. Therefore, we describe two hydrodynamical simulations with cooling beyond this density balance, one with the same parameters as model i in Paper I ( now called model i'), which was presented there with and without cooling, and the second with higher gas densities in the jet pulses ( model iv'). Methods. Hydrodynamical simulations, with a further approximated cooling treatment compared to Paper I, were used to be able to enlarge the computational domain. Results. The transition causes changes in the expansion of the cocoon and therefore the morphology of the jet, e. g. a larger radial width of the jet knots. We investigate the radiation properties of the jets, the bremsstrahlung and optical emissivities, integrated emission maps, and synthetic absorption line profiles. Conclusions. The conclusion that the high observed velocities in CH Cygni, R Aquarii, and MWC 560 favor the models with cooling is unchanged by the transition. The observed parallel features in R Aquarii can be produced by the internal knots or by a variable dense radiative shell of shocked ambient medium. The absorption line profiles show that the real parameters in MWC 560 are closer to model iv' than to model i'. C1 Landessternwarte Heidelberg, D-69117 Heidelberg, Germany. RP Stute, M (reprint author), CALTECH, Jet Prop Lab, Mail Stop 169-506,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Matthias.Stute@jpl.nasa.gov NR 19 TC 6 Z9 6 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 450 IS 2 BP 645 EP 654 DI 10.1051/0004-6361:20054089 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 031LZ UT WOS:000236707400018 ER PT J AU Strazzullo, V Rosati, P Stanford, SA Lidman, C Nonino, M Demarco, R Eisenhardt, PE Ettori, S Mainieri, V Toft, S AF Strazzullo, V Rosati, P Stanford, SA Lidman, C Nonino, M Demarco, R Eisenhardt, PE Ettori, S Mainieri, V Toft, S TI The near-infrared luminosity function of cluster galaxies beyond redshift one SO ASTRONOMY & ASTROPHYSICS LA English DT Review DE galaxies : clusters : general; galaxy : evolution; galaxy : formation; galaxies : luminosity function; mass function; cosmology : observations ID COLOR-MAGNITUDE RELATION; DEEP FIELD SOUTH; TO-LIGHT RATIOS; STELLAR MASS FUNCTIONS; S-BAND LUMINOSITY; X-RAY; FUNDAMENTAL PLANE; RICH CLUSTERS; ELLIPTIC GALAXIES; COMA CLUSTER AB Aims. We determined the K-s band luminosity function (LF), and inferred the corresponding stellar mass function, of cluster galaxies at redshift z similar or equal to 1.2, using near-infrared images of three X-ray luminous clusters at z = 1.11, 1.24, 1.27. Methods. The composite LF was derived down to M* + 4, by means of statistical background subtraction, and is well described by a Schechter function with K-s* = 20.5(-1)(+0.4) and alpha = -1.0(-0.3)(+0.2). Using available X-ray mass profiles we determined the M/L ratios of these three clusters, which tend to be lower than those measured in the local universe. Finally, from the Ks band composite LF we derived the stellar mass function of cluster galaxies. Results. With these data, no significant difference can be seen between the cluster galaxies LF and the LF of field galaxies at similar redshift. We also found no significant evolution out to z similar or equal to 1.2 in the bright (< M* + 4) part of the LF probed in this study, apart from a brightening of similar or equal to 1.3 mag of the characteristic magnitude of the high redshift LF. We confirm, and extend to higher redshift, the result from previous work that the redshift evolution of the characteristic magnitude M* is consistent with passive evolution of a stellar population formed at z > 2. Conclusions. The results obtained in this work support and extend previous findings that most of the stars in bright galaxies were formed at high redshift, and that K-s-bright (M > 10(11) M circle dot) galaxies were already in place at z similar or equal to 1.2, at least in the central regions of X-ray luminous clusters. Together with recent results on the field galaxy stellar mass function, this implies that most of the stellar mass is already assembled in massive galaxies by z similar or equal to 1, both in low and high density environments. C1 Univ Naples Federico II, Dipartimento Sci Fisiche, I-80126 Naples, Italy. European So Observ, D-85748 Garching, Germany. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. LLNL, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. European So Observ, Santiago 19, Chile. Osserv Astron Trieste, Inst Nazl Astrofis, I-34131 Trieste, Italy. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Osservatorio Astron Bologna, Ist Nazl Astrofis, I-40127 Bologna, Italy. Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. Yale Univ, Dept Astron, New Haven, CT 06520 USA. RP Strazzullo, V (reprint author), Univ Naples Federico II, Dipartimento Sci Fisiche, Via Cinthia, I-80126 Naples, Italy. EM vstrazzu@eso.org RI Ettori, Stefano/N-5004-2015; OI Ettori, Stefano/0000-0003-4117-8617; Nonino, Mario/0000-0001-6342-9662 NR 116 TC 40 Z9 40 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 450 IS 3 BP 909 EP 923 DI 10.1051/0004-6361:20054341 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032TK UT WOS:000236797400006 ER PT J AU Weidenspointner, G Shrader, CR Knodlseder, J Jean, P Lonjou, V Guessoum, N Diehl, R Gillard, W Harris, MJ Skinner, GK von Ballmoos, P Vedrenne, G Roques, JP Schanne, S Sizun, P Teegarden, BJ Schonfelder, V Winkler, C AF Weidenspointner, G Shrader, CR Knodlseder, J Jean, P Lonjou, V Guessoum, N Diehl, R Gillard, W Harris, MJ Skinner, GK von Ballmoos, P Vedrenne, G Roques, JP Schanne, S Sizun, P Teegarden, BJ Schonfelder, V Winkler, C TI The sky distribution of positronium annihilation continuum emission measured with SPI/INTEGRAL SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : observations; Galaxy : bulge ID 4TH GALACTIC QUADRANT; GAMMA-RAY EMISSION; LINE EMISSION; SPECTRAL-ANALYSIS; SPI OBSERVATIONS; MILKY-WAY; RADIATION; SPECTROMETER; GALAXY; INTEGRAL/SPI AB We present a measurement of the sky distribution of positronium (Ps) annihilation continuum emission obtained with the SPI spectrometer on board ESA's INTEGRAL observatory. The only sky region from which significant Ps continuum emission is detected is the Galactic bulge. The Ps continuum emission is circularly symmetric about the Galactic centre, with an extension of about 8 degrees FWHM. Within measurement uncertainties, the sky distribution of the Ps continuum emission is consistent with that found by us for the 511 keV electron-positron annihilation line using SPI. Assuming that 511 keV line and Ps continuum emission follow the same spatial distribution, we derive a Ps fraction of 0.92 +/- 0.09. These results strengthen our conclusions regarding the origin of positrons in our Galaxy based on observations of the 511 keV line. In particular, they suggest that the main source of Galactic positrons is associated with an old stellar population, such as Type Ia supernovae, classical novae, or low-mass X-ray binaries. Light dark matter is a possible alternative source of positrons. C1 Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 4, France. NASA, Goddard Space Flight Ctr, LHEA, Greenbelt, MD 20771 USA. Amer Univ Sharjah, Coll Arts & Sci, Dept Phys, Sharjah, U Arab Emirates. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. CEA Saclay, DSM, DAPNIA, SAp, F-91191 Gif Sur Yvette, France. ESA, ESTEC, Sci Operat & Data Syst Div, SCI SD, NL-2201 AZ Noordwijk, Netherlands. RP Ctr Etud Spatiale Rayonnements, 9 Ave Colonel Roche, F-31028 Toulouse 4, France. EM Georg.Weidenspointner@cesr.fr RI Guessoum, Nidhal/C-3051-2013; OI GILLARD, William/0000-0003-4744-9748 NR 45 TC 71 Z9 71 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 450 IS 3 BP 1013 EP 1021 DI 10.1051/0004-6361:20054046 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032TK UT WOS:000236797400015 ER PT J AU Justtanont, K Olofsson, G Dijkstra, C Meyer, AW AF Justtanont, K Olofsson, G Dijkstra, C Meyer, AW TI Near-infrared observations of water-ice in OH/IR stars SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : AGB and post-AGB; stars : circumstellar matter; stars : evolution; stars : late-type; stars : mass-loss; infrared : stars ID MASS-LOSS RATES; CIRCUMSTELLAR ENVELOPES; RADIATIVE-TRANSFER; EVOLVED STARS; CARBON STARS; CO EMISSION; OH 26.5+0.6; DUST; AGB; ENVIRONMENTS AB A search for the near-infrared water-ice absorption band was made in a number of very red OH/IR stars which are known to exhibit the 10 mu m silicate absorption. As a by-product, accurate positions of these highly reddened objects are obtained. We derived a dust mass loss rate for each object by modelling the spectral energy distribution and the gas mass loss rate by solving the equation of motion for the dust drag wind. The derived mass loss rates show a strong correlation with the silicate optical depth as well as that of the water-ice. The stars have a high mass loss rate (> 10(-4) M circle dot yr(-1)) with an average gas-to-dust mass ratio of 110. In objects which show the 3.1 mu m water-ice absorption, the near-IR slope is much steeper than those with no water-ice. Comparison between our calculated mass loss rates and those derived from OH and CO observations indicates that these stars have recently increased their mass loss rates. C1 AlbaNova, Stockholm Observ, Dept Astron, S-10691 Stockholm, Sweden. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. NASA, Ames Res Ctr, USRA, SOFIA, Moffett Field, CA 94035 USA. RP Justtanont, K (reprint author), AlbaNova, Stockholm Observ, Dept Astron, S-10691 Stockholm, Sweden. OI /0000-0003-1689-9201 NR 33 TC 22 Z9 22 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 450 IS 3 BP 1051 EP 1059 DI 10.1051/0004-6361:20054569 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032TK UT WOS:000236797400018 ER PT J AU Broeg, C Joergens, V Fernandez, M Husar, D Hearty, T Ammler, M Neuhauser, R AF Broeg, C Joergens, V Fernandez, M Husar, D Hearty, T Ammler, M Neuhauser, R TI Rotational periods of T Tauri stars in Taurus-Auriga, south of Taurus-Auriga, and in MBM12 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : rotation; stars : fundamental parameters; stars : starspots; stars : variables : general; stars : pre-main sequence; stars : binaries : eclipsing ID MAIN-SEQUENCE STARS; ALL-SKY SURVEY; HIGH-RESOLUTION SPECTROSCOPY; LOW-MASS STARS; MOLECULAR CLOUDS; STATISTICAL-METHODS; ASTRONOMICAL DATA; FORMING REGION; UPPER LIMITS; ZERO-AGE AB Context. The ROSAT All-Sky Survey detected many young objects outside any known star forming region. Their formation is yet unclear. Aims. In order to improve the knowledge about these X-ray bright objects we aimed at measuring their rotational properties, which are fundamental stellar parameters, and at comparing them to young objects inside molecular clouds. Methods. We monitored photometric variations of 5 T Tauri stars in MBM12 and of 26 young objects in the Taurus-Auriga molecular cloud and south of it. Among the 26 young objects there are 17 weak-line T Tauri stars, 7 zero age main-sequence stars and 2 of unknown type. In addition, 2 main-sequence K-type stars were observed, and one comparison star turned out to be an eclipsing binary. Results. We found periodic variations for most of the targets. The measured periods of the T Tauri stars range from 0.57 to 7.4 days. The photometric variation can be ascribed to rotational modulation caused by spots. For a few of the periodic variables, changes of the light curve profile within several weeks are reported. For one star such changes have been observed in data taken two years apart. The exceptions are two eclipsing systems. One so far unknown system - GSC2.2N3022313162 - shows a light curve with full phase coverage having both primary and secondary minima well resolved. It has an orbital period of 0.59075 days. From our spectroscopic observations we conclude that it is a main sequence star of spectral type F2 +/- 4. We further compared the off cloud weak-line T Tauri stars to the weak- line T Tauri stars inside the molecular cloud in terms of rotational period distribution. Statistical analysis of the two samples shows that both groups are likely to have the same period distribution. C1 Inst Astrophys, D-07745 Jena, Germany. Univ Sternwarte, D-07745 Jena, Germany. Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. Leiden Observ, Sterrewacht Leiden, NL-2300 RA Leiden, Netherlands. Max Planck Inst Astron, D-69117 Heidelberg, Germany. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. BAV eV, D-12169 Berlin, Germany. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Broeg, C (reprint author), Inst Astrophys, Schillergasschen 2-3, D-07745 Jena, Germany. EM broeg@astro.uni-jena.de NR 65 TC 8 Z9 8 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2006 VL 450 IS 3 BP 1135 EP U192 DI 10.1051/0004-6361:20053777 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032TK UT WOS:000236797400024 ER PT J AU Kusenko, A Schissel, J Stecker, FW AF Kusenko, A Schissel, J Stecker, FW TI Interactions of ultrahigh-energy cosmic rays with photons in the galactic center SO ASTROPARTICLE PHYSICS LA English DT Article DE cosmic rays ID UNIVERSAL RADIATION FIELD; ZATSEPIN-KUZMIN CUTOFF; LORENTZ INVARIANCE; SOLAR PHOTONS; SPECTRUM; PHOTODISINTEGRATION; INFLATION; PARTICLES; NEUTRINOS; AMMONIA AB Ultrahigh-energy cosmic rays passing through the central region of the Galaxy interact with starlight and the infrared photons. Both nuclei and protons generate secondary fluxes of photons and neutrinos on their passage through the central region. We compute the fluxes of these secondary particles, the observations of which can be used to improve one's understanding of origin and composition of ultrahigh-energy comic rays, especially if the violation of the Greisen-Zatespin-Kuzmin cutoff is confirmed by the future data. (c) 2006 Elsevier B.V. All rights reserved. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Kusenko, A (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. EM kusenko@ucla.edu RI Stecker, Floyd/D-3169-2012 NR 40 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-6505 J9 ASTROPART PHYS JI Astropart Phys. PD MAY PY 2006 VL 25 IS 4 BP 242 EP 245 DI 10.1016/j.astropartphys.2006.02.001 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 042YO UT WOS:000237566700002 ER PT J AU Sasaki, M Gaetz, TJ Blair, WP Edgar, RJ Morse, JA Plucinsky, PP Smith, RK AF Sasaki, M Gaetz, TJ Blair, WP Edgar, RJ Morse, JA Plucinsky, PP Smith, RK TI Far-Ultraviolet and X-ray observations of the reverse shock in the Small Magellanic Cloud supernova remnant 1E 0102.2-7219 SO ASTROPHYSICAL JOURNAL LA English DT Article DE shock waves; supernova remnants; ultraviolet : ISM; X-rays : individual (1E 0102.2-7219) ID MOLECULAR-HYDROGEN; EXTINCTION CURVES; YOUNG; 1E-0102.2-7219; ABUNDANCES; SPECTRUM; INSTABILITIES; ELEMENTS; ATLAS AB We present Far Ultraviolet Spectroscopic Explorer (FUSE) and X-Ray Multi-Mirror Mission (XMM-Newton) data for the reverse shock of the O-rich supernova remnant (SNR) 1E 0102.2-7219 in the Small Magellanic Cloud (SMC). The FUSE observations cover three regions with significantly different optical [O (III)] intensities, all associated with the relatively bright part of the X-ray ring. Emission lines of O (VI) lambda lambda 1032, 1038 are clearly detected in the FUSE spectra. The XMM-Newton EPIC MOS 1/2 spectra are dominated by strong emission lines of O, Ne, and Mg. By combining the O (VI) doublet emission with the O (VII) triplet and O (VIII) Ly alpha fluxes from the X-ray spectra and assuming a nonequilibrium ionization (NEI) model with a single ionization timescale for the spectra, we find an increase of the ionization timescale tau from north (tau approximate to 0.6 x 10(11) s cm(-3)) to southeast (tau approximate to 2 x 10(11) s cm(-3)). This is indicative of increasing density in the X-ray-bright ring, in good agreement with the optical [O (III)] emission, which is strongest in the southeast. However, if we assume a plane-parallel shock model with a distribution of ionization timescales, the O (VI) emission appears to be inconsistent with O (VII) and O (VIII) in X-rays. The analysis of the total X-ray spectra shows that there is no consistent set of values for the temperature and ionization timescale that can explain the observed line ratios for O, Ne, and Mg. This would be consistent with a structured distribution of the ejecta, as the O, Ne, and Mg would have interacted with the reverse shock at different times. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM msasaki@cfa.harvard.edu RI Sasaki, Manami/P-3045-2016 OI Sasaki, Manami/0000-0001-5302-1866 NR 35 TC 11 Z9 11 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 260 EP 269 DI 10.1086/500789 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600021 ER PT J AU de Gregorio-Monsalvo, I Gomez, JF Suarez, O Kuiper, TBH Rodriguez, LF Jimenez-Bailon, E AF de Gregorio-Monsalvo, I Gomez, JF Suarez, O Kuiper, TBH Rodriguez, LF Jimenez-Bailon, E TI CCS and NH3 emission associated with low-mass young stellar objects SO ASTROPHYSICAL JOURNAL LA English DT Review DE astrochemistry; ISM : clouds; ISM : evolution; ISM : molecules; stars : formation; stars : pre-main-sequence ID STAR-FORMING REGIONS; MONTH MONITORING SURVEY; VELOCITY MOLECULAR GAS; HERBIG-HARO OBJECTS; DARK CLOUD CORES; H-II-REGIONS; IRAS SOURCES; DENSE CORES; WATER MASERS; BIPOLAR OUTFLOW AB In this work we present a sensitive and systematic single-dish survey of CCS emission ( complemented with ammonia observations) at 1 cm, toward a sample of low- and intermediate-mass young star-forming regions known to harbor water maser emission, made with NASA's 70 m antenna at Robledo de Chavela, Spain. Out of the 40 star-forming regions surveyed in the CCS (2(1) - 1(0)) line, only six low- mass sources show CCS emission: one transitional object between the prestellar and protostellar Class 0 phase (GF9-2), three Class 0 protostars (L1448-IRS3, L1448C, and B1-IRS), a Class I source (L1251A), and a young T Tauri star (NGC 2071 North). Since CCS is considered an "early-time'' (less than or similar to 10(5) yr) molecule, we explain these results by either proposing a revision of the classification of the age of NGC 2071 North and L1251A, or suggesting the possibility that the particular physical conditions and processes of each source affect the destruction/production of the CCS. No statistically significant relationship was found between the presence of CCS and parameters of the molecular outflows and their driving sources. Nevertheless, we found a significant relationship between the detectability of CCS and the ammonia peak intensity ( higher in regions with CCS), but not with its integrated intensity. This tendency may suggest that the narrower ammonia line widths in the less turbulent medium associated with younger cores may compensate for the differences in ammonia peak intensity, rendering differences in integrated intensity negligible. From the CCS detection rate we derive a lifetime of this molecule of similar or equal to(0.7-3) x 10(4) yr in low-mass star-forming regions. C1 Lab Astrofis Espacial & Fis Fundamental INTA, E-28080 Madrid, Spain. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Nacl Autonoma Mexico, Ctr Radioastron & Astrofis, Morelia 58089, Michoacan, Mexico. ESA, RSSD, XMM Newton Sci Operat Ctr, E-28080 Madrid, Spain. RP de Gregorio-Monsalvo, I (reprint author), Lab Astrofis Espacial & Fis Fundamental INTA, Apartado 50727, E-28080 Madrid, Spain. RI Gomez, Jose Francisco/D-8392-2016 OI Gomez, Jose Francisco/0000-0002-7065-542X NR 109 TC 15 Z9 15 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 319 EP 329 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600025 ER PT J AU Simpson, JP Colgan, SWJ Erickson, EF Burton, MG Schultz, ASB AF Simpson, JP Colgan, SWJ Erickson, EF Burton, MG Schultz, ASB TI Hubble Space Telescope NICMOS polarization measurements of OMC-1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : ISM; infrared : stars; ISM : individual (Orion BN/ KL); ISM : magnetic fields; stars : formation; stars : pre-main sequence ID INTERSTELLAR DUST GRAINS; BECKLIN-NEUGEBAUER OBJECT; ORION MOLECULAR CLOUD; MAGNETIC-FIELD; MASS FUNCTION; BN OBJECT; INFRARED POLARIMETRY; TRAPEZIUM CLUSTER; PROPER MOTIONS; NEBULA CLUSTER AB We present 2 mu m polarization measurements of positions in the IRc2 and BN regions of the OrionMolecular Cloud (OMC-1) made with NICMOS Camera 2 (0."2 resolution) on the Hubble Space Telescope. Our results are as follows: BN is similar to 29% polarized by dichroic absorption and appears to be the illuminating source for most of the nebulosity to its north and for up to similar to 5" to its south. Although the stars are probably all polarized by dichroic absorption, there are a number of compact but non-point-source objects that could be polarized by a combination of both dichroic absorption and local scattering of starlight. We identify several candidate YSOs, including an approximately edge-on bipolar YSO 8"7 east of BN, and a deeply embedded variable star. Additional strongly polarized sources are IRc2-B, IRc2-D, and IRc7, all of which are obviously self-luminous at mid-infrared wavelengths and may be YSOs. None of these is a reflection nebula illuminated by a star located near radio source I, as was previously suggested. Other IRc sources are clearly reflection nebulae: IRc3 appears to be illuminated by IRc2-B or a combination of the IRc2 sources, and IRc4 and IRc5 appear to be illuminated by an unseen star in the vicinity of radio source I, or by star n or IRc2-A. Trends in the magnetic field direction are inferred from the polarization of the 26 stars that are bright enough to be seen as NICMOS point sources. The most polarized star has a polarization position angle different from its neighbors by similar to 40 degrees, but in agreement with the grain alignment inferred from millimeter polarization measurements of the cold dust cloud in the southern part of OMC-1. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ New S Wales, Sch Phys, Sydney, NSW 2052, Australia. SETI Inst, Mountain View, CA 94043 USA. RP Simpson, JP (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. EM simpson@cygnus.arc.nasa.gov; sean.colgan@nasa.gov; erickson@cygnus.arc.nasa.gov; mgb@phys.unsw.edu.au; schultz@cygnus.arc.nasa.gov RI Colgan, Sean/M-4742-2014 NR 80 TC 24 Z9 24 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 339 EP 353 DI 10.1086/500656 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600027 ER PT J AU Zhang, B Fan, YZ Dyks, J Kobayashi, S Meszaros, P Burrows, DN Nousek, JA Gehrels, N AF Zhang, B Fan, YZ Dyks, J Kobayashi, S Meszaros, P Burrows, DN Nousek, JA Gehrels, N TI Physical processes shaping gamma-ray burst X-ray afterglow light curves: Theoretical implications from the Swift X-ray telescope observations SO ASTROPHYSICAL JOURNAL LA English DT Review DE gamma rays : bursts; radiation mechanisms : nonthermal; shock waves ID REVERSE SHOCK EMISSION; CONTINUOUS ENERGY INJECTION; EARLY OPTICAL AFTERGLOWS; INTERNAL SHOCKS; MILLISECOND PULSARS; RELATIVISTIC JETS; WIND ENVIRONMENTS; FIREBALL MODEL; COMMON ORIGIN; PROMPT PHASE AB With the successful launch of the Swift Gamma-Ray Burst Explorer, a rich trove of early X-ray afterglow data has been collected by its onboard X-Ray Telescope (XRT). Some interesting features are emerging, including a distinct rapidly decaying component preceding the conventional afterglow component in many sources, a shallow decay component before the more "normal'' decay component observed in a good fraction of GRBs, and X-ray flares in nearly half of the afterglows. In this paper we systematically analyze the possible physical processes that shape the properties of the early X-ray afterglow light curves and use the data to constrain various models. We suggest that the steep decay component is consistent with the tail emission of the prompt gamma-ray bursts and/or the X-ray flares. This provides strong evidence that the prompt emission and afterglow emission are likely two distinct components, supporting the internal origin of the GRB prompt emission. The shallow decay segment observed in a group of GRBs suggests that very likely the forward shock keeps being refreshed for some time. This might be caused by either a long-lived central engine, or a wide distribution of the shell Lorentz factors, or else possibly the deceleration of a Poynting flux-dominated flow. X-ray flares suggest that the GRB central engine is very likely still active after the prompt gamma-ray emission is over, but with a reduced activity at later times. In some cases, the central engine activity even extends to days after the burst triggers. Analyses of early X-ray afterglow data reveal that GRBs are indeed highly relativistic events and that early afterglow data of many bursts, starting from the beginning of the XRT observations, are consistent with the afterglow emission from an ISM environment. C1 Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Jiangsu, Peoples R China. Chinese Acad Sci, Inst Geog, Natl Astron Observ, Beijing 100012, Peoples R China. Nicholas Copernicus Astron Ctr, Lab Astrophys 1, PL-87100 Torun, Poland. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zhang, B (reprint author), Univ Nevada, Dept Phys, 4505 S Maryland Pkwy, Las Vegas, NV 89154 USA. RI Gehrels, Neil/D-2971-2012 NR 148 TC 604 Z9 611 U1 2 U2 21 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 354 EP 370 DI 10.1086/500723 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600028 ER PT J AU Nousek, JA Kouveliotou, C Grupe, D Page, KL Granot, J Ramirez-Ruiz, E Patel, SK Burrows, DN Mangano, V Barthelmy, S Beardmore, AP Campana, S Capalbi, M Chincarini, G Cusumano, G Falcone, AD Gehrels, N Giommi, P Goad, MR Godet, O Hurkett, CP Kennea, JA Moretti, A O'Brien, PT Osborne, JP Romano, P Tagliaferri, G Wells, AA AF Nousek, JA Kouveliotou, C Grupe, D Page, KL Granot, J Ramirez-Ruiz, E Patel, SK Burrows, DN Mangano, V Barthelmy, S Beardmore, AP Campana, S Capalbi, M Chincarini, G Cusumano, G Falcone, AD Gehrels, N Giommi, P Goad, MR Godet, O Hurkett, CP Kennea, JA Moretti, A O'Brien, PT Osborne, JP Romano, P Tagliaferri, G Wells, AA TI Evidence for a canonical gamma-ray burst afterglow light curve in the Swift XRT data SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; radiation mechanisms : nonthermal ID NEUTRON-STARS; REFRESHED SHOCKS; ACCRETION DISKS; FIREBALL MODEL; KINETIC-ENERGY; CENTRAL ENGINE; OPTICAL FLASH; GRB 050509B; BLACK-HOLES; HOST GALAXY AB We present new observations of the early X-ray afterglows of the first 27 gamma-ray bursts (GRBs) well observed by the Swift X-Ray Telescope (XRT). The early X-ray afterglows show a canonical behavior, where the light curve broadly consists of three distinct power-law segments: (1) an initial very steep decay (alpha(t-alpha) with 3 less than or similar to alpha(1) less than or similar to 5), followed by (2) a very shallow decay (0:5P less than or similar to alpha(2) less than or similar to 1.0), and finally ( 3) a somewhat steeper decay (1 less than or similar to alpha(3) less than or similar to 1.5). These power-law segments are separated by two corresponding break times, t(break,1) less than or similar to 500 s and 10(3) s less than or similar to t(break,2) less than or similar to 10(4) s. On top of this canonical behavior, many events have superimposed X-ray flares, which are most likely caused by internal shocks due to long-lasting sporadic activity of the central engine, up to several hours after the GRB. We find that the initial steep decay is consistent with it being the tail of the prompt emission, from photons that are radiated at large angles relative to our line of sight. The first break in the light curve (t(break,1)) takes place when the forward shock emission becomes dominant, with the intermediate shallow flux decay (alpha 2) likely caused by the continuous energy injection into the external shock. When this energy injection stops, a second break is then observed in the light curve (t(break,2)). This energy injection increases the energy of the afterglow shock by at least a factor of f greater than or similar to 4 and augments the already severe requirements for the efficiency of the prompt gamma-ray emission. C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Natl Space Sci Technol Ctr, NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94309 USA. Inst Adv Study, Princeton, NJ 08540 USA. Univ Space Res Assoc, MSFC, NASA, IPA, Columbia, MD 21044 USA. Ist Fis Spazialee Fis Cosm, Sez Palermo, INAF, Palermo, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Osserv Astron Brera, INAF, Merate, Italy. ASI Sci Data Ctr, Frascati, Italy. Univ Milan, Dipartimento Fis, Milan, Italy. RP Nousek, JA (reprint author), Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; OI giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 83 TC 566 Z9 573 U1 0 U2 15 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 389 EP 400 DI 10.1086/500724 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600031 ER PT J AU Fortney, JJ Saumon, D Marley, MS Lodders, K Freedman, RS AF Fortney, JJ Saumon, D Marley, MS Lodders, K Freedman, RS TI Atmosphere, interior, and evolution of the metal-rich transiting planet HD 149026b SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : eclipsing; planetary systems; radiative transfer; stars : individual (HD 149026, HD 189733) ID EXTRASOLAR GIANT PLANETS; MASS DWARF STARS; B-LIKE PLANETS; BROWN DWARFS; HOT-JUPITERS; THERMAL STRUCTURE; PHASE-SEPARATION; MODELS; SATURN; URANUS AB We investigate the atmosphere and interior of the new transiting planet HD 149026b, which appears to be very rich in heavy elements. We first compute model atmospheres at metallicities ranging from solar to 10 times solar and show how for cases with high metallicity or inefficient redistribution of energy from the dayside, the planet may develop a hot stratosphere due to absorption of stellar flux by TiO and VO. The spectra predicted by these models are very different than cooler atmosphere models without stratospheres. The spectral effects are potentially detectable with the Spitzer Space Telescope. In addition, the models with hot stratospheres lead to a large limb brightening, rather than darkening. We compare the atmosphere of HD 149026b to other well-known transiting planets, including the recently discovered HD 189733b, which we show has a planet-to-star flux ratio twice that of HD 209458 and TrES-1. The methane abundance in the atmosphere of HD 189733b is a sensitive indicator of atmospheric temperature and metallicity and can be constrained with Spitzer IRAC observations. We then turn to interior studies of HD 149026b and use a grid of self-consistent model atmospheres and high-pressure equations of state for all components to compute thermal evolution models of the planet. We estimate that the mass of heavy elements within the planet is in the range of 60-93 M(circle plus). Finally, we discuss trends in the radii of transiting planets with metallicity in light of this new member of the class. C1 NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Washington Univ, Dept Earth & Planetary Sci, Planetary Chem Lab, St Louis, MO 63130 USA. SETI Inst, Mountain View, CA 94043 USA. RP Fortney, JJ (reprint author), NASA, Ames Res Ctr, Space Sci & Astrobiol Div, MS 245-3, Moffett Field, CA 94035 USA. EM jfortney@arc.nasa.gov RI Marley, Mark/I-4704-2013; OI Fortney, Jonathan/0000-0002-9843-4354 NR 72 TC 127 Z9 128 U1 2 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 495 EP 504 DI 10.1086/500920 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600043 ER PT J AU Burlaga, LF Ness, NF Acuna, MH AF Burlaga, LF Ness, NF Acuna, MH TI Magnetic fields in the heliosheath: Voyager 1 observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : magnetic fields ID LOCAL INTERSTELLAR-MEDIUM; HELIOSPHERIC TERMINAL SHOCK; ANOMALOUS COSMIC-RAYS; SOLAR-WIND; MAGNETOHYDRODYNAMIC TURBULENCE; FLOW DOWNSTREAM; DISTANT HELIOSPHERE; OUTER HELIOSPHERE; STREAM STRUCTURE; PICKUP PROTONS AB Magnetic fields in the heliosheath were observed by Voyager 1 (V1) from 2004 DOY 352 to 2005 125, when V1 moved from 94.04 to 95.24 AU at 34 degrees.1N. The strongest fields (0.31 nT, observed on 2005 DOY 8-9, occurred in a narrow peak containing very large amplitude fluctuations. This peak was associated with a cusplike minimum in the flux of ions > 0.5MeV. The largest structure observed in the interval was a unipolar magnetic sector, which V1 entered on 2004 DOY 360 and exited on 2005 DOY 110. In the sector, the distribution functions of each of the three components of hour averages of B relative to their mean values were Gaussian; the widths of these distributions were all comparable, indicating that the fluctuations in B were nearly isotropic. The distribution of hour averages of the magnetic field strength B was also Gaussian in the sector. A high-resolution sample of turbulence in the sector shows that the fluctuations in both the magnitude and each of the components of the 48 s averages of B also have Gaussian distributions. The turbulence on this scale is compressible and isotropic relative to the mean B. This sample of the turbulence contains ordered features, including magnetic holes. The leading sector boundary occurred within an 18 hr interval on 2004 DOY 360. The trailing sector boundary occurred within a approximate to 14 hr interval on 2005 DOY 110-111, beginning with a very narrow (approximate to 20 minutes) "D-sheet'' (consistent with magnetic reconnection). Both sector boundaries were associated with large variations in B, including magnetic holes and waves. There was a large, abrupt decrease in B from 0.14 to 0.05 nT across the trailing sector boundary, and a region with low values of B (approximate to 0.05 nT) moved past V1 for more than 15 days following the sector boundary. C1 NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. Catholic Univ Amer, Inst Astrophys & Computat Sci, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Planetary Magnetospheres Lab, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Code 912-2, Greenbelt, MD 20771 USA. EM leonard.f.burlaga@nasa.gov; nfnudel@yahoo.com; mario.h.acuna@nasa.gov NR 84 TC 55 Z9 55 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2006 VL 642 IS 1 BP 584 EP 592 DI 10.1086/500826 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 038GH UT WOS:000237206600052 ER PT J AU Iglesias-Paramo, J Buat, V Takeuchi, TT Xu, K Boissier, S Boselli, A Burgarella, D Madore, BF De Paz, AG Bianchi, L Barlow, TA Byun, YI Donas, J Forster, K Friedman, PG Heckman, TM Jelinski, PN Lee, YW Malina, RF Martin, DC Milliard, B Morrissey, PF Neff, SG Rich, RM Schiminovich, D Seibert, M Siegmund, OHW Small, T Szalay, AS Welsh, BY Wyder, TK AF Iglesias-Paramo, J Buat, V Takeuchi, TT Xu, K Boissier, S Boselli, A Burgarella, D Madore, BF De Paz, AG Bianchi, L Barlow, TA Byun, YI Donas, J Forster, K Friedman, PG Heckman, TM Jelinski, PN Lee, YW Malina, RF Martin, DC Milliard, B Morrissey, PF Neff, SG Rich, RM Schiminovich, D Seibert, M Siegmund, OHW Small, T Szalay, AS Welsh, BY Wyder, TK TI Star formation in the nearby universe: The ultraviolet and infrared points of view SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE infrared : galaxies; surveys; ultraviolet : galaxies ID HUBBLE DEEP FIELD; GALAXY LUMINOSITY FUNCTION; HIGH-REDSHIFT GALAXIES; LYMAN-BREAK GALAXIES; FORMATION HISTORY; DUST ATTENUATION; LOCAL UNIVERSE; STARBURST GALAXIES; DISK GALAXIES; EVOLUTION-EXPLORER AB This work presents the main ultraviolet (UV) and far-infrared (FIR) properties of two samples of nearby galaxies selected from the GALEX (gimel = 2315 angstrom, hereafter NUV) and IRAS (gimel = 60 mu m) surveys, respectively. They are built in order to obtain detection at both wavelengths for most of the galaxies. Star formation rate (SFR) estimators based on the UV and FIR emissions are compared. Systematic differences are found between the SFR estimators for individual galaxies based on the NUV fluxes corrected for dust attenuation and on the total IR luminosity. A combined estimator based on NUV and IR luminosities seems to be the best proxy over the whole range of values of SFR. Although both samples present similar average values of the birthrate parameter b, their star-formation-related properties are substantially different: NUV-selected galaxies tend to show larger values of b for lower masses, SFRs, and dust attenuation, supporting previous scenarios of star formation history (SFH). Conversely, about 20% of the FIR-selected galaxies show high values of b, SFR, and NUV attenuation. These galaxies, most of them being LIRGs and ULIRGs, break down the downsizing picture of SFH; however, their relative contribution per unit volume is small in the local universe. Finally, the cosmic SFR density of the local universe is estimated in a consistent way from the NUV and IR luminosities. C1 Astrophys Lab, F-13376 Marseille, France. Inst Astrofis Andalucia, E-18080 Granada, Spain. CALTECH, Space Astrophys Lab, Pasadena, CA 91125 USA. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. Johns Hopkins Univ, Ctr Astrophys Sci, Baltimore, MD 21218 USA. Yonsei Univ, Ctr Space Astrophys, Seoul 120749, South Korea. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. RP Iglesias-Paramo, J (reprint author), Astrophys Lab, F-13376 Marseille, France. RI Gil de Paz, Armando/J-2874-2016; OI Gil de Paz, Armando/0000-0001-6150-2854; malina, roger/0000-0003-3399-3865; Iglesias-Paramo, Jorge/0000-0003-2726-6370 NR 59 TC 93 Z9 93 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 EI 1538-4365 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAY PY 2006 VL 164 IS 1 BP 38 EP 51 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 039JD UT WOS:000237300900002 ER PT J AU Hurley, K Mitrofanov, I Kozyrev, A Litvak, M Sanin, A Grinkov, V Charyshnikov, S Boynton, W Fellows, C Harshman, K Hamara, D Shinohara, C Starr, R AF Hurley, K Mitrofanov, I Kozyrev, A Litvak, M Sanin, A Grinkov, V Charyshnikov, S Boynton, W Fellows, C Harshman, K Hamara, D Shinohara, C Starr, R TI Mars odyssey joins the third interplanetary network SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE catalogs; gamma rays : bursts ID GAMMA-RAY BURST; GIANT FLARE; MAGNETAR SGR-1806-20; ULYSSES SUPPLEMENT; GRB-020405; POLARIZATION; SPECTROMETER; GRB-021206; AFTERGLOW; MISSION AB The Mars Odyssey spacecraft carries two experiments that are capable of detecting cosmic gamma-ray bursts and soft gamma repeaters. Since 2001 April they have detected over 275 bursts and, in conjunction with the other spacecraft of the interplanetary network, localized many of them rapidly and precisely enough to allow sensitive multiwavelength counterpart searches. We present the Mars Odyssey mission and describe the burst capabilities of the two experiments in detail. We explain how the spacecraft timing and ephemeris have been verified in-flight using bursts from objects whose precise positions are known by other means. Finally, we show several examples of localizations and discuss future plans for the Odyssey mission and the network as a whole. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Moscow Space Res Inst, Moscow 117810, Russia. Univ Arizona, Lumar & Planetary Lab, Tucson, AZ 85721 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hurley, K (reprint author), Univ Calif Berkeley, Space Sci Lab, 7 Gauss Way, Berkeley, CA 94720 USA. EM khurley@ssl.berkeley.edu NR 32 TC 16 Z9 16 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAY PY 2006 VL 164 IS 1 BP 124 EP 129 DI 10.1086/501352 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 039JD UT WOS:000237300900006 ER PT J AU Landi, E Bhatia, AK AF Landi, E Bhatia, AK TI Atomic data and spectral line intensities for Ar XI SO ATOMIC DATA AND NUCLEAR DATA TABLES LA English DT Article ID COLLISION STRENGTHS; EMISSION-LINES; ISOELECTRONIC SEQUENCE; GROUND CONFIGURATION; OSCILLATOR-STRENGTHS; RATE COEFFICIENTS; IRON PROJECT; NI-XXI; IONS; TRANSITIONS AB Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Ar XI. The configurations used are 2s(2)2p(4), 2s2p(5), 2p(6), 2s(2)2p(3)3s, 2s(2)2p(3)3p, and 2s(2)2P(3)3d giving rise to 86 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies (30, 60, 90, 120, and 150 Ry) in the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(8)-10(14) cm(-3) at an electron temperature of log T-c (K) = 6.3, corresponding to the maximum abundance of Ar XI. Relative and absolute spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database. (c) 2006 Elsevier Inc. All rights reserved. C1 ARTEP Inc, Columbia, MD 21044 USA. USN, Res Lab, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Landi, E (reprint author), ARTEP Inc, Columbia, MD 21044 USA. EM landi@poppeo.nrl.navy.mil RI Landi, Enrico/H-4493-2011 NR 27 TC 4 Z9 4 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0092-640X J9 ATOM DATA NUCL DATA JI Atom. Data Nucl. Data Tables PD MAY PY 2006 VL 92 IS 3 BP 305 EP 374 DI 10.1016/j.adt.2006.01.002 PG 70 WC Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Physics GA 043XW UT WOS:000237637300001 ER PT J AU Convertino, VA Ratliff, DA Eisenhower, KC Warren, C Doerr, DF Idris, AH Lurie, KG AF Convertino, VA Ratliff, DA Eisenhower, KC Warren, C Doerr, DF Idris, AH Lurie, KG TI Inspiratory impedance effects on hemodynamic responses to orthostasis in normal subjects SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE respiration; heart rate; stroke volume; cardiac output; peripheral vascular resistance; impedance threshold device; tilt test; hypotension ID BLOOD-PRESSURE; VASCULAR-RESISTANCE; HEMORRHAGIC-SHOCK; SPACE-FLIGHT; STAND TEST; HYPOTENSION; MICROGRAVITY; SPACEFLIGHT; INTOLERANCE; FINGER AB Background: Breathing through an impedance threshold device (ITD) might prove effective as a countermeasure against post-spaceflight orthostatic hypotension since it increased blood pressure (BP) and cardiac output in supine human subjects. Objective: We tested the hypothesis that spontaneous breathing through an ITD would attenuate the reduction in stroke volume and BP during orthostasis in human subjects. Methods: There were 19 volunteers (10 men, 9 women) who completed two 80 degrees head-up tilt (HUT) protocols with (active) and without (sham control) an ITD set to open at -7 cm H2O pressure. Heart rate (HR), stroke volume (SV), cardiac output (CO), mean arterial pressure (MAP), and total peripheral resistance (TPR) were measured non-invasively during transition from supine to HUT. Results: HUT caused significant elevation in HR and reductions in SV, CO, TPR, and MAP. Hemodynamic effects of HUT were similar for sham and active ITD. Further analysis revealed a subset (n = 11) of subjects who demonstrated a > 20% decrease in SV during HUT with the sham ITD. In this subset of subjects, the ITD attenuated (p = 0.004) the %Delta SV (-22.5 +/- 3.0%) during HUT compared with the sham ITD (%Delta SV = -37.4 +/- 2.6%). There was no statistical effect of ITD use in the subgroup who demonstrated < 20% reduction in SV (-16.6 +/- 0.4%). Conclusions: Use of an ITD may provide significant protection against orthostatic compromise in individuals with greater than 20% reductions in SV, such as astronauts returning from space. C1 USA, Inst Surg Res, Ft Sam Houston, TX 78234 USA. NASA, Off Hlth & Med Syst, Dynam Corp, Kennedy Space Ctr, FL 32899 USA. NASA, Spaceflight & Life Sci Training Program, Kennedy Space Ctr, FL 32899 USA. NASA, Biomed Res Lab, Kennedy Space Ctr, FL 32899 USA. Univ Texas, SW Med Ctr, Dept Emergency Med, Dallas, TX 75230 USA. Adv Circulatory Syst Inc, Minneapolis, MN USA. Hennepin Cty Med Ctr, Dept Emergency Med, Minneapolis, MN 55415 USA. RP Convertino, VA (reprint author), USA, Inst Surg Res, 3400 Rawley R Chambers Ave,Bldg 3611, Ft Sam Houston, TX 78234 USA. EM victor.convertino@amedd.army.mil NR 35 TC 12 Z9 12 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAY PY 2006 VL 77 IS 5 BP 486 EP 493 PG 8 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 040GD UT WOS:000237366100003 PM 16708528 ER PT J AU Desai, AR Davis, KJ Senff, CJ Ismail, S Browell, EV Stauffer, DR Reen, BP AF Desai, Ankur R. Davis, Kenneth J. Senff, Christoph J. Ismail, Syed Browell, Edward V. Stauffer, David R. Reen, Brian P. TI A case study on the effects of heterogeneous soil moisture on mesoscale boundary-layer structure in the Southern Great Plains, USA Part I: Simple prognostic model SO BOUNDARY-LAYER METEOROLOGY LA English DT Article DE boundary-layer depth; convective boundary layer; lidar; soil moisture; surface buoyancy flux ID ESTIMATING SURFACE FLUXES; REMOTELY-SENSED DATA; SENSIBLE HEAT-FLUX; WATER CONTENT; SCALE; CLOUD; PARAMETERIZATION; CIRCULATIONS; METEOROLOGY; INVERSION AB The atmospheric boundary-layer (ABL) depth was observed by airborne lidar and balloon soundings during the Southern Great Plains 1997 field study (SGP97). This paper is Part I of a two-part case study examining the relationship of surface heterogeneity to observed ABL structure. Part I focuses on observations. During two days (12-13 July 1997) following rain, midday convective ABL depth varied by as much as 1.5 km across 400 km, even with moderate winds. Variability in ABL depth was driven primarily by the spatial variation in surface buoyancy flux as measured from short towers and aircraft within the SGP97 domain. Strong correlation was found between time-integrated buoyancy flux and airborne remotely sensed surface soil moisture for the two case-study days, but only a weak correlation was found between surface energy fluxes and vegetation greenness as measured by satellite. A simple prognostic one-dimensional ABL model was applied to test to what extent the soil moisture spatial heterogeneity explained the variation in north-south ABL depth across the SGP97 domain. The model was able to better predict mean ABL depth and variations on horizontal scales of approximately 100 km using observed soil moisture instead of constant soil moisture. Subsidence, advection, convergence/divergence and spatial variability of temperature inversion strength also contributed to ABL depth variations. In Part II, assimilation of high-resolution soil moisture into a three-dimensional mesoscale model (MM5) is discussed and shown to improve predictions of ABL structure. These results have implications for ABL models and the influence of soil moisture on mesoscale meteorology. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. NOAA, Environm Technol Lab, Atmospher Lidar Div, Boulder, CO USA. NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23665 USA. RP Desai, AR (reprint author), Penn State Univ, Dept Meteorol, 503 Walker Bldg, University Pk, PA 16802 USA. EM adesai@psu.edu RI Senff, Christoph/I-2592-2013; Desai, Ankur/A-5899-2008; Manager, CSD Publications/B-2789-2015 OI Desai, Ankur/0000-0002-5226-6041; NR 56 TC 20 Z9 20 U1 2 U2 8 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD MAY PY 2006 VL 119 IS 2 BP 195 EP 238 DI 10.1007/s10546-005-9024-6 PG 44 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 047FA UT WOS:000237864000001 ER PT J AU Prins, EM Velden, CS Hawkins, JD Turk, FJ Daniels, JM Dittberner, GJ Holmlund, K Hood, RE Laing, AG Nasiri, SL Puschell, JJ Shepherd, JM Zapotocny, JV AF Prins, Elaine M. Velden, Christopher S. Hawkins, Jeffrey D. Turk, F. Joseph Daniels, Jaime M. Dittberner, Gerald J. Holmlund, Kenneth Hood, Robbie E. Laing, Arlene G. Nasiri, Shaima L. Puschell, Jeffery J. Shepherd, J. Marshall Zapotocny, John V. TI 13TH AMS Conference on Satellite Meteorology and Oceanography SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Editorial Material C1 Univ Wisconsin, CIMSS, SSEC, Madison, WI USA. USN, Res Lab, Monterey, CA USA. NOAA, NESDIS, Off Res & Applicat, Camp Springs, MD USA. NOAA, NESDIS, Silver Spring, MD USA. EUMETSTAT, Darmstadt, Germany. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Santa Barbara Remote Sensing, Raytheon Elect Syst, Goleta, CA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USAF Weather Agcy, Offutt AFB, NE USA. RP Prins, EM (reprint author), 17207 Alexandra Way, Grass Valley, CA USA. EM elaine.prins@ssec.wisc.edu RI Nasiri, Shaima/C-8044-2011; Daniels, Jaime/E-7933-2011 OI Daniels, Jaime/0000-0002-9438-6631 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAY PY 2006 VL 87 IS 5 BP 633 EP 637 DI 10.1175/BAMS-87-5-633 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 047JP UT WOS:000237875900023 ER PT J AU Zak, M AF Zak, M TI Expectation-based intelligent control SO CHAOS SOLITONS & FRACTALS LA English DT Article AB New dynamics paradigms-negative diffusion and terminal attractors-are introduced to control noise and chaos. The applied control forces are composed of expectations governed by the associated Fokker-Planck and Liouville equations. The approach is expanded to a general concept of intelligent control via expectations. Relevance to control in livings is emphasized and illustrated by neural nets with mirror neurons. (c) 2005 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Adv Comp Algorithms & IVHM Grp, Pasadena, CA 91109 USA. RP Zak, M (reprint author), CALTECH, Jet Prop Lab, Adv Comp Algorithms & IVHM Grp, 4800 Oak Grove Dr,MS 126-347, Pasadena, CA 91109 USA. EM Michail.Zak@jpl.nasa.gov NR 8 TC 9 Z9 9 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-0779 J9 CHAOS SOLITON FRACT JI Chaos Solitons Fractals PD MAY PY 2006 VL 28 IS 3 BP 616 EP 626 DI 10.1016/j.chaos.2005.08.009 PG 11 WC Mathematics, Interdisciplinary Applications; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA 016BP UT WOS:000235595900004 ER PT J AU Gormly, S AF Gormly, S TI Storm clouds SO CIVIL ENGINEERING LA English DT Letter C1 NASA, Ames Res Ctr, Carson City, NV USA. RP Gormly, S (reprint author), NASA, Ames Res Ctr, Carson City, NV USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0885-7024 J9 CIVIL ENG JI Civil Eng. PD MAY PY 2006 VL 76 IS 5 BP 10 EP 10 PG 1 WC Engineering, Civil SC Engineering GA 041GW UT WOS:000237443600002 ER PT J AU Tena-Zaera, R Ryan, MA Katty, A Hodes, G Bastide, S Levy-Clement, C AF Tena-Zaera, Ramon Ryan, Margaret A. Katty, Abou Hodes, Gary Bastide, Stephane Levy-Clement, Claude TI Fabrication and characterization of ZnO nanowires/CdSe/CuSCN eta-solar cell SO COMPTES RENDUS CHIMIE LA English DT Article; Proceedings Paper CT 15th International Conference on Photochemical Conversion and Storage of Solar Energy CY JUL 04-07, 2004 CL Paris, FRANCE DE nano-heterojunctions; eta-solar cells; ZnO nanowires; CdSeCuSCN; electrodeposition ID EXTREMELY THIN ABSORBER; OPTICAL-PROPERTIES; PHOTOVOLTAIC CELL; OXIDE-FILMS; CDSE; CUSCN; ELECTRODEPOSITION; DEPOSITION; SUBSTRATE AB ZnO/CdSe/CuSCN extremely thin absorber (eta)-solar cells based oil ZnO nanowires have been successfully realized using easily accessible electrochemical and solution deposition techniques. An n-type ZnO film consisting of free-standing single crystal nanowires several microns high and 100-200 nm in diameter was-deposited oil a conducting glass (SnO2:F) substrate covered by a thin spray pyrolysis ZnO electronic blocking layer. A 30-40-nm-thin layer of CdSe absorber was electrodeposited, coating the ZnO nanowires. The voids between the ZnO/CdSe nanowires were filled with p-type CuSCN; the entire assembly formed a p-i-n junction. The ZnO/CdSe nanowire layer exhibited a high light-trapping effect, with all effective absorbance of similar to 89% and effective reflectance of similar to 8% in the 400-800 nm region of the solar spectrum (AM 1.5). The effects of an annealing process on the Use grain size and on the energy conversion efficiency of the eta-solar cell have been analyzed. The obtained efficiencies, for cells with annealed CdSe (1.5-2.3%) show that the ZnO/CdSe/CuSCN nano-heterostructure is an interesting option for developing new solar cell devices. To cite this article: R. Tena-Zaera et al., CR. Chimie 9 (2006). (C) 2005 Academie des sciences. Published by Elsevier SAS. All rights reserved. C1 CNRS, Inst Sci Chim Seine Amont, LCMTR, F-94320 Thiais, France. Univ Valencia, Dept Fis Aplicada & Electromagnetisme, E-46100 Burjassot, Spain. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Weizmann Inst Sci, Dept Mat & Interfaces, IL-76100 Rehovot, Israel. RP Levy-Clement, C (reprint author), CNRS, Inst Sci Chim Seine Amont, LCMTR, 2-8 Rue Henri Dunant, F-94320 Thiais, France. EM claude.levy-clement@glvt-cnrs.fr RI Tena-Zaera, Ramon/M-2413-2014 OI Tena-Zaera, Ramon/0000-0002-1525-7760 NR 37 TC 74 Z9 74 U1 3 U2 50 PU ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS PA 23 RUE LINOIS, 75724 PARIS, FRANCE SN 1631-0748 EI 1878-1543 J9 CR CHIM JI C. R. Chim. PD MAY-JUN PY 2006 VL 9 IS 5-6 BP 717 EP 729 DI 10.1016/j.crci.2005.03.034 PG 13 WC Chemistry, Multidisciplinary SC Chemistry GA 042AD UT WOS:000237498400023 ER PT J AU Wentz, EA Stefanov, WL Gries, C Hope, D AF Wentz, Elizabeth A. Stefanov, William L. Gries, Corinna Hope, Diane TI Land use and land cover mapping from diverse data sources for an and urban environments SO COMPUTERS ENVIRONMENT AND URBAN SYSTEMS LA English DT Article DE urban land use; urban land cover; landsat thematic mapper; aerial photography; ground observations; Phoenix AZ ID REMOTE-SENSING DATA; AERIAL-PHOTOGRAPHY; SATELLITE IMAGERY; TM IMAGERY; CLASSIFICATION; AREA; INFORMATION; GROWTH; INTEGRATION; ESTIMATORS AB Accurate and up-to-date data describing land use and land cover change support studies of urban growth such as quantifying the amount of rural to urban change and identifying change trajectories. This paper compares three methods for identifying urban land use/land cover, based on aerial photography, satellite imagery, and ground observations. While it might be natural to assume that classification based on ground observations would be the most accurate, this may not always be the case. Here we aim to quantify to what degree these three different classification approaches agree or contradict each other and to understand why. Land use/land cover data derived from these three sources were compared for the Phoenix metropolitan area, an and urban region undergoing rapid urbanization. Our results show that satellite data are well suited to classify land use/land cover where land use categories are associated with homogeneous land cover at the subpixel level, but that for land use categories with subpixel land cover complexity, aerial photographs or ground observations are needed to aid in the classification. (c) 2004 Elsevier Ltd. All rights reserved. C1 Arizona State Univ, Dept Geog, Tempe, AZ 85287 USA. NASA, Lyndon B Johnson Space Ctr, Image Sci & Anal Lab, Houston, TX 77058 USA. Arizona State Univ, Ctr Environm Studies, Tempe, AZ 85287 USA. RP Wentz, EA (reprint author), Arizona State Univ, Dept Geog, Tempe, AZ 85287 USA. EM wentz@asu.edu NR 55 TC 20 Z9 24 U1 2 U2 15 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0198-9715 J9 COMPUT ENVIRON URBAN JI Comput. Environ. Urban Syst. PD MAY PY 2006 VL 30 IS 3 BP 320 EP 346 DI 10.1016/j.compenvurbsys.2004.07.002 PG 27 WC Computer Science, Interdisciplinary Applications; Engineering, Environmental; Environmental Studies; Geography; Operations Research & Management Science SC Computer Science; Engineering; Environmental Sciences & Ecology; Geography; Operations Research & Management Science GA 113TG UT WOS:000242619700006 ER PT J AU Stone, RP AF Stone, RP TI Coral habitat in the Aleutian Islands of Alaska: depth distribution, fine-scale species associations, and fisheries interactions SO CORAL REEFS LA English DT Article DE cold-water corals; gorgonians; hydrocorals; Aleutian Islands; fishing disturbance; Emergent epifauna ID DEEP-SEA; GORGONIAN CORALS; ATLANTIC CANADA; MEGAFAUNA; GULF; ABUNDANCE; GROWTH; SHELF; USA AB The first in situ exploration of Aleutian Island coral habitat was completed in 2002 to determine the distribution of corals, to examine fine-scale associations between targeted fish species and corals, and to investigate the interaction between the areas' diverse fisheries and coral habitat. Corals, mostly gorgonians and hydrocorals, were present on all 25 seafloor transects and at depths between 27 and 363 m, but were most abundant between 100 and 200 m depth. Mean coral abundance (1.23 colonies m(-2)) far exceeded that reported for other high-latitude ecosystems and high-density coral gardens (3.85 colonies m(-2)) were observed at seven locations. Slope and offshore pinnacle habitats characterized by exposed bedrock, boulders, and cobbles generally supported the highest abundances of coral and fish. Overall, 85% of the economically important fish species observed on transects were associated with corals and other emergent epifauna. Disturbance to the seafloor from bottom-contact fishing gear was evident on 88% of the transects, and approximately 39% of the total area of the seafloor observed had been disturbed. Since cold-water corals appear to be a ubiquitous feature of seafloor habitats in the Aleutian Islands, fisheries managers face clear challenges integrating coral conservation into an ecosystem approach to fisheries management. C1 Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Lab, Juneau, AK 99801 USA. RP Stone, RP (reprint author), Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. EM bob.stone@noaa.gov NR 33 TC 91 Z9 98 U1 4 U2 23 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0722-4028 EI 1432-0975 J9 CORAL REEFS JI Coral Reefs PD MAY PY 2006 VL 25 IS 2 BP 229 EP 238 DI 10.1007/s00338-006-0091-z PG 10 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 039GA UT WOS:000237292800014 ER PT J AU Fleck, B Muller, D Haugan, S Duarte, LS Siili, T Gurman, JB AF Fleck, B Muller, D Haugan, S Duarte, LS Siili, T Gurman, JB TI 10 years of SOHO SO ESA BULLETIN-EUROPEAN SPACE AGENCY LA English DT Article AB Since its launch on 2 December 1995, SOHO has revolutionised our understanding of the Sun. It has provided the first images of structures and flows below the Sun's surface and of activity on the far side. SOHO has revealed the Sun's extremely dynamic atmosphere, provided evidence for the transfer of magnetic energy from the surface to the outer solar atmosphere, the corona, through a 'magnetic carpet'. and identified the source regions of the fast solar wind. It has revolutionised our understanding of solar-terrestrial relations and dramatically improved our space weather-forecasting by its continuous stream of images covering the atmosphere, extended corona and far side. The findings are documented in an impressive number of scientific publications: over 2500 papers in refereed journals since launch, representing the work of over 2300 individual scientists. At the same time, SOHO's easily accessible, spectacular data and fundamental scientific results have captured the imagination of the space science community and the general public alike. As a byproduct of the efforts to provide real-time data to the public, amateurs now dominate SOHO's discovery of over 1100 Sun-grazing comets. C1 NASA, Solar & Solar Terr Missions Div, ESA Res & Sci Support Dept, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fleck, B (reprint author), NASA, Solar & Solar Terr Missions Div, ESA Res & Sci Support Dept, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Fleck, Bernhard/C-9520-2012 NR 0 TC 0 Z9 0 U1 0 U2 1 PU EUROPEAN SPACE AGENCY PI NOORDWIJK PA ESTEC, PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0376-4265 J9 ESA BULL-EUR SPACE JI ESA Bull.-Eur. Space Agency PD MAY PY 2006 IS 126 BP 24 EP 32 PG 9 WC Engineering, Aerospace SC Engineering GA 048BF UT WOS:000237921900004 ER PT J AU Simon, D Simon, DL AF Simon, Dan Simon, Donald L. TI Kalman filter constraint switching for turbofan engine health estimation SO EUROPEAN JOURNAL OF CONTROL LA English DT Article DE estimation; gas turbine engines; Kalman filter; quadratic programming; residuals; state constraints ID STATE ESTIMATION AB Kalman filters are often used to estimate the state variables of a dynamic system. However, in the application of Kalman filters some known signal information is often either ignored or dealt with heuristically. For instance, state variable constraints (which may be based on physical considerations) are often neglected because they do not fit easily into the structure of the Kalman filter. Recently published work has shown a new method for incorporating state variable inequality constraints in the Kalman filter. The resultant filter is a combination of a standard Kalman filter and a quadratic programming problem. The incorporation of state variable constraints has been shown to generally improve the filters estimation accuracy. However, the incorporation of inequality constraints poses some risk to the estimation accuracy. After all, the Kalman filter is theoretically optimal, so the incorporation of heuristic constraints may degrade the optimality of the filter. This paper proposes a way to switch the filter constraints so that the state estimates follow the unconstrained (theoretically optimal) filter when the confidence in the unconstrained filter is high. When confidence in the unconstrained filter is not so high, then we use our heuristic knowledge to constrain the state estimates. The confidence measure is based on the agreement of measurement residuals with their theoretical values. If some measurement residuals are low, and those residuals are highly sensitive to a given state, then we are confident that the unconstrained estimate of that state is correct. Otherwise, we incorporate our heuristic knowledge as state constraints. The algorithm is demonstrated on a linearized simulation of a turbofan engine to estimate engine health. C1 Cleveland State Univ, Cleveland, OH 44115 USA. USA, Res Lab, NASA Glenn Res Ctr, Cleveland, OH 44135 USA. RP Simon, D (reprint author), Cleveland State Univ, Stilwell Hall Room 332,2121 Euclid Ave, Cleveland, OH 44115 USA. EM d.j.simon@csuohio.edu NR 23 TC 4 Z9 4 U1 2 U2 4 PU LAVOISIER PI CACHAN PA 14, RUE DE PROVIGNY, 94236 CACHAN, FRANCE SN 0947-3580 J9 EUR J CONTROL JI Eur. J. Control PD MAY-JUN PY 2006 VL 12 IS 3 BP 331 EP 343 DI 10.3166/ejc.12.341-343 PG 13 WC Automation & Control Systems SC Automation & Control Systems GA 104ND UT WOS:000241964200009 ER PT J AU Pappa, RS Jones, TW Lunsford, CB Meyer, CG AF Pappa, RS Jones, TW Lunsford, CB Meyer, CG TI In-vacuum photogrammetry of a ten-meter square solar sail SO EXPERIMENTAL TECHNIQUES LA English DT Article C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. PEBCO Inc, Paducah, KY USA. RP Pappa, RS (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 5 TC 0 Z9 0 U1 0 U2 2 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0732-8818 J9 EXP TECHNIQUES JI Exp. Tech. PD MAY-JUN PY 2006 VL 30 IS 3 BP 46 EP 51 DI 10.1111/j.1747-1567.2006.00042.x PG 6 WC Engineering, Mechanical; Mechanics; Materials Science, Characterization & Testing SC Engineering; Mechanics; Materials Science GA 048RZ UT WOS:000237965500005 ER PT J AU Ghoshal, A Kim, HS Kim, J Choi, SB Prosser, WH Tai, H AF Ghoshal, A Kim, HS Kim, J Choi, SB Prosser, WH Tai, H TI Modeling delamination in composite structures by incorporating the Fermi-Dirac distribution function and hybrid damage indicators SO FINITE ELEMENTS IN ANALYSIS AND DESIGN LA English DT Article DE computational modeling; delaminations; hybrid damage indicator; Fermi-Dirac distribution function ID ORDER ZIGZAG THEORY; DYNAMIC CHARACTERISTICS; VIBRATION ANALYSIS; LAYERWISE THEORY; PLATE-THEORY; BEAMS AB Conventional finite element approaches for modeling delaminations in laminated composite structures use the Heaviside unit step function at the interfacial nodes in the delaminated zone of the structure to model the possible jumps in the displacement field during "breathing" of the delaminated layers. In quantum mechanics, the Fermi-Dirac distribution applies to Fermion particles whose characteristics are half-integer spins. The present paper uses the Fermi-Dirac distribution function to model a smoother transition in the displacement and the strain fields of the delaminated interfaces during the opening and closing of the delaminated layers under vibratory loads. This paper successfully shows that the Fermi-Dirac distribution function can be used to more accurately model the dynamic effects of delaminations in laminated composite structures. Optimizing the parameters in the Fermi-Dirac distribution function can lead to more accurate modeling of the dynamic and transient behavior of the delaminated zones in laminated composite structures. This paper also effectively demonstrates how hybrid sensors comprising of out of plane displacement sensors and in plane strain sensors can effectively map a composite structure to detect and locate the delaminated zones. It also shows how simple mode shapes can be used to determine the locations of single and multiple delaminations in laminated composite structures. (c) 2005 Elsevier B.V. All rights reserved. C1 Inha Univ, Dept Mech Engn, Inchon 402751, South Korea. United Technol Res Ctr, E Hartford, CT 06108 USA. NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, Hampton, VA 23681 USA. RP Kim, HS (reprint author), Inha Univ, Dept Mech Engn, 253 YongHyun-Dong, Inchon 402751, South Korea. EM heungsookim@inha.ac.kr RI Kim, Heung Soo /F-6611-2011; choi, seungbok/G-6922-2011; OI Kim, Heung Soo /0000-0001-7057-5174; choi, seungbok/0000-0001-6262-2815; Kim, Jaehwan/0000-0002-6152-2924 NR 21 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-874X J9 FINITE ELEM ANAL DES JI Finite Elem. Anal. Des. PD MAY PY 2006 VL 42 IS 8-9 BP 715 EP 725 DI 10.1016/j.finel.2005.10.008 PG 11 WC Mathematics, Applied; Mechanics SC Mathematics; Mechanics GA 038JV UT WOS:000237216700008 ER PT J AU Aubrey, A Cleaves, HJ Chalmers, JH Skelley, AM Mathies, RA Grunthaner, FJ Ehrenfreund, P Bada, JL AF Aubrey, A Cleaves, HJ Chalmers, JH Skelley, AM Mathies, RA Grunthaner, FJ Ehrenfreund, P Bada, JL TI Sulfate minerals and organic compounds on Mars SO GEOLOGY LA English DT Article DE Mars; sulfates; evaporites; amino acids; gypsum; jarosite; anhydrite; kerogen ID OMEGA/MARS EXPRESS; MERIDIANI-PLANUM; NATURAL SAMPLES; AMINO-ACIDS; PRESERVATION; SUBLIMATION; ENANTIOMERS; CALIFORNIA; REGION; LIFE AB Strong evidence for evaporitic sulfate minerals such as gypsum and jarosite has recently been found on Mars. Although organic molecules are often codeposited with terrestrial evaporitic minerals, there have been no systematic investigations of organic components in sulfate minerals. We report here the detection of organic material, including amino acids and their amine degradation products, in ancient terrestrial sulfate minerals. Amino acids and amines appear to be preserved for geologically long periods in sulfate mineral matrices. This suggests that sulfate minerals should be prime targets in the search for organic compounds, including those of biological origin, on Mars. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. RP Aubrey, A (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. EM jbada@ucsd.edu OI Cleaves, Henderson/0000-0003-4101-0654 NR 30 TC 83 Z9 88 U1 9 U2 26 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 2006 VL 34 IS 5 BP 357 EP 360 DI 10.1130/G22316.1 PG 4 WC Geology SC Geology GA 039NN UT WOS:000237312900010 ER PT J AU Henderson-Sellers, A Fischer, M Aleinov, I McGuffie, K Riley, WJ Schmidt, GA Sturm, K Yoshimura, K Irannejad, P AF Henderson-Sellers, A Fischer, M Aleinov, I McGuffie, K Riley, WJ Schmidt, GA Sturm, K Yoshimura, K Irannejad, P TI Stable water isotope simulation by current land-surface schemes: Results of iPILPS Phase 1 SO GLOBAL AND PLANETARY CHANGE LA English DT Article DE water isotopes; land parameterization; model intercomparison; Craig-Gordon scheme; PILPS ID MODELS; CIRCULATION; DELTA-O-18; RUNOFF; PRECIPITATION; TRANSPIRATION; PROJECT; CLIMATE; VAPOR AB Phase I of isotopes in the Project for Intercomparison of Land-surface Parameterization Schemes (iPILPS) compares the simulation of two stable water isotopologues (H-1(2) O-18 and (HH)-H-1-H-2 O-16) at the land-atmosphere interface. The simulations are offline, with forcing from an isotopically enabled regional model for three locations selected to offer contrasting climates and ecotypes: an evergreen tropical forest, a sclerophyll eucalypt forest and a mixed deciduous wood. Here, we report on the experimental framework, the quality control undertaken on the simulation results and the method of intercomparisons employed. The small number of available isotopically enabled land-surface schemes (ILSSs) limits the drawing of strong conclusions, but, despite this, there is shown to be benefit in undertaking this type of isotopic intercomparison. Although validation of isotopic simulations at the land surface must await more and much more complete, observational campaigns, we find that the empirically based Craig-Gordon parameterization (of isotopic fractionation during evaporation) gives adequately realistic isotopic simulations when incorporated in a wide range of land-surface codes. By introducing two new tools for understanding isotopic variability from the land surface, the isotope transfer function and the iPILPS plot, we show that different hydrological parameterizations cause very different isotopic responses. We show that ILSS-simulated isotopic equilibrium is independent of the total water and energy budget (with respect to both equilibration time and state), but interestingly the partitioning of available energy and water is a function of the models' complexity. (C) 2006 Elsevier B.V. All rights reserved. C1 Australian Nucl Sci & Technol Org, Inst Nucl Geophysiol, Lucas Hts Sci & Technol Ctr, Menai, NSW 2234, Australia. Columbia Univ, New York, NY 10025 USA. NASA, Goddard Inst Space Sci, New York, NY 10025 USA. Univ Technol Sydney, Dept Appl Phys, Sydney, NSW 2007, Australia. LBNL, Div Earth Sci, Berkeley, CA USA. Univ Tokyo, Tokyo 1538505, Japan. Univ Tehran, Inst Geophys, Tehran 646614155, Iran. RP Fischer, M (reprint author), Australian Nucl Sci & Technol Org, Inst Nucl Geophysiol, Lucas Hts Sci & Technol Ctr, Private Mail Bag 1, Menai, NSW 2234, Australia. EM ipilps@ansto.gov.au RI Schmidt, Gavin/D-4427-2012; Riley, William/D-3345-2015; Henderson-Sellers, Ann/H-5323-2011; Yoshimura, Kei/F-2041-2010; Fischer, Matt/G-8160-2011; Sturm, Christophe/C-3055-2012 OI Schmidt, Gavin/0000-0002-2258-0486; Riley, William/0000-0002-4615-2304; Yoshimura, Kei/0000-0002-5761-1561; Fischer, Matt/0000-0002-4052-3549; NR 30 TC 27 Z9 29 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD MAY PY 2006 VL 51 IS 1-2 BP 34 EP 58 DI 10.1016/j.gloplacha.2006.01.003 PG 25 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 049TY UT WOS:000238041400004 ER PT J AU Aleinov, I Schmidt, GA AF Aleinov, I. Schmidt, G. A. TI Water isotopes in the GISS ModelE land surface scheme SO GLOBAL AND PLANETARY CHANGE LA English DT Article DE iPILPS; stable water isotopes; land surface model; GCM; GISS ModelE ID STABLE-ISOTOPES; CLIMATE; SNOW; GCM; SIMULATIONS; VALIDATION AB We describe the isotope-capable Land Surface Model (LSM) developed at NASA Goddard Institute for Space Studies (GISS). This model is a part of the GISS ModelE General Circulation Model (GCM), which includes the water isotopes (H2O)-O-18 and HDO as tracers in every aspect of the model's hydrological cycle. We discuss results for the soil isotopes from a number of full GCM simulations. In particular, we focus upon the spin up and equilibrium behavior of the isotope fields in a present day (ca. 1980) control simulation and the response of the isotopes to forcings over transient AMIP-style 20th century simulations. In addition, we investigate whether the isotope fields are affected by a change in the runoff algorithm, and so examine whether the isotope fields have the potential to constrain model land surface physics. (C) 2006 Elsevier B.V. All rights reserved. C1 Columbia Univ, Ctr Climate Syst Res, New York, NY 10025 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Aleinov, I (reprint author), Columbia Univ, Ctr Climate Syst Res, 2880 Broadway, New York, NY 10025 USA. EM ialeinov@giss.nasa.gov RI Schmidt, Gavin/D-4427-2012 OI Schmidt, Gavin/0000-0002-2258-0486 NR 25 TC 18 Z9 19 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 EI 1872-6364 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD MAY PY 2006 VL 51 IS 1-2 BP 108 EP 120 DI 10.1016/j.gloplacha.2005.12.010 PG 13 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 049TY UT WOS:000238041400008 ER PT J AU Gillespie, TW Zutta, BR Early, MK Saatchi, S AF Gillespie, TW Zutta, BR Early, MK Saatchi, S TI Predicting and quantifying the structure of tropical dry forests in South Florida and the Neotropics using spaceborne imagery SO GLOBAL ECOLOGY AND BIOGEOGRAPHY LA English DT Article DE climate; Florida; forest structure; hurricanes; Landsat; NED; Neotropics; SRTM; tropical dry forests ID LANDSAT TM DATA; VEGETATION INDEX; FLORISTIC COMPOSITION; PRIMARY PRODUCTIVITY; CENTRAL-AMERICA; RAIN-FOREST; BIOMASS; DIVERSITY; PATTERNS; BOLIVIA AB Aim This research examines environmental theories and remote sensing methods that have been hypothesized to be associated with tropical dry forest structure. Location Tropical dry forests of South Florida and the Neotropics. Methods Field measurements of stand density, basal area and tree height were collected from 22 stands in South Florida and 30 stands in the Neotropics. In South Florida, field measurements were compared to climatic (temperature, precipitation, hurricane disturbance) and edaphic (rockiness, soil depth) variables, spectral indices (NDVI, IRI, MIRI) from Landsat 7 ETM+, and estimates of tree height from the Shuttle Radar Topography Mission (SRTM) and the National Elevation Dataset (NED). Environmental variables associated with tropical dry forest structure in South Florida were compared to tropical dry forest in other Neotropical sites. Results There were significant correlations among temperature and precipitation, and stand density and tree height in South Florida. There were significant correlations between (i) stand density and mean NDVI and standard deviation of NDVI, (ii) MIRI and stand density, basal area and mean tree height, and (iii) estimates of tree height from SRTM with maximum tree height. In the Neotropics, there were no relationships between temperature or precipitation and tropical dry forest structure, however, Neotropical sites that experience hurricane disturbance had significantly shorter tree heights and higher stand densities. Main conclusions It is possible to predict and quantify the forest structure characteristics of tropical dry forests using climatic data, Landsat 7 ETM+ imagery and SRTM data in South Florida. However, results based on climatic data are region-specific and not necessarily transferable between tropical dry forests at a continental spatial scale. Spectral indices from Landsat 7 ETM+ can be used to quantify forest structure characteristics, but SRTM data are currently not transferable to other regions. Hurricane disturbance has a significant impact on forest structure in the Neotropics. C1 Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Ecol & Evolutionary Biol, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gillespie, TW (reprint author), Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. EM tg@geog.ucla.edu; bzutta@ucla.edu; mearly@ucla.edu; saatchi@congo.jpl.nasa.gov NR 57 TC 18 Z9 18 U1 1 U2 12 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1466-822X EI 1466-8238 J9 GLOBAL ECOL BIOGEOGR JI Glob. Ecol. Biogeogr. PD MAY PY 2006 VL 15 IS 3 BP 225 EP 236 DI 10.1111/j.1466-8238.2005.00203.x PG 12 WC Ecology; Geography, Physical SC Environmental Sciences & Ecology; Physical Geography GA 036ZP UT WOS:000237116800002 ER PT J AU Konopliv, AS Yoder, CF Standish, EM Yuan, DN Sjogren, WL AF Konopliv, AS Yoder, CF Standish, EM Yuan, DN Sjogren, WL TI A global solution for the Mars static and seasonal gravity, Mars orientation, Phobos and Deimos masses, and Mars ephemeris SO ICARUS LA English DT Article DE Mars, interior; geophysics; satellites of Mars; planetary dynamics; asteroids ID ORBITER LASER ALTIMETER; ASTEROID MASSES; SNOW DEPTH; ROTATION; FIELD; TOPOGRAPHY; TRACKING; SURVEYOR; PATHFINDER; THICKNESS AB With the collection of six years of MGS tracking data and three years of Mars Odyssey tracking data, there has been a continual improvement in the JPL Mars gravity field determination. This includes the measurement of the seasonal changes in the gravity coefficients (e.g., (J) over bar (2), (J) over bar (3), (C) over bar (21), (C) over bar (21), (S) over bar (21), (C) over bar (31), (S) over bar (31) ) caused by the mass exchange between the polar ice caps and atmosphere. This paper describes the latest gravity field MGS95J to degree and order 95. The improvement comes from additional tracking data and the adoption of a more complete Mars orientation model with nutation, instead of the IAU 2000 model. Free wobble of the Mars' spin axis, i.e. polar motion, has been constrained to be less than 10 mas by looking at the temporal history of (C) over bar (21) and (S) over bar (21). A strong annual signature is observed in (C) over bar (21), and this is it Mixture of polar motion and ice mass redistribution. The Love number Solution with a subset of Odyssey tracking data is consistent with the previous liquid outer core determination from MGS tracking data [Yoder et a]., 2003. Science 300, 299-303], giving a combined solution of k(2) = 0. 152 +/- 0.009 using MGS and Odyssey tracking data. The solutions for the masses of the Mars' moons show consistency between MGS, Odyssey, and Viking data sets; Phobos GM = (7.16 +/- 0.005) x 10(-4) km(3)/s(2) and Deimos GM = (0.98 +/- 0.07) x 10(-4) km(3)/s(2). Average MGS orbit errors, determined from differences in the overlaps of orbit solutions, have been reduced to 10-cm in the radial direction and 1.5 m along the spacecraft velocity and normal to the orbit plane. Hence, the ranging to the MGS and Odyssey spacecraft has resulted in position measurements of the Mars system center-of-mass relative to the Earth to an accuracy of one meter, greatly reducing the Mars ephemeris errors by several orders of magnitude, and providing mass estimates for Asteroids 1 Ceres, 2 Pallas, 3 Juno, 4 Vesta, and 324 Bamberga. (c) 2006 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM alex.konopliv@jpl.nasa.gov NR 60 TC 152 Z9 162 U1 2 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD MAY PY 2006 VL 182 IS 1 BP 23 EP 50 DI 10.1016/j.icarus.2005.12.025 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 041CK UT WOS:000237430600003 ER PT J AU Achterberg, RK Conrath, BJ Gierasch, PJ AF Achterberg, RK Conrath, BJ Gierasch, PJ TI Cassini CIRS retrievals of ammonia in Jupiter's upper troposphere SO ICARUS LA English DT Article DE Jupiter, atmosphere; atmospheres, structure; atmospheres, dynamics ID GREAT-RED-SPOT; ROTOTRANSLATIONAL ABSORPTION-SPECTRA; PROBE MASS-SPECTROMETER; VOYAGER IRIS; CLOUD STRUCTURE; ATMOSPHERIC COMPOSITION; JOVIAN ATMOSPHERE; OUTER PLANETS; ABUNDANCES; PAIRS AB The zonal mean ammonia abundance on Jupiter between the 400- and 500-mbar pressure levels is inferred as a function of latitude front Cassini Composite Infrared Spectrometer data. Near the Great Red Spot, the ammonia abundance is mapped as a function of latitude and longitude. The Equatorial Zone is rich in ammonia, with a relative humidity near unity. The North and South Equatorial Belts are depleted relative to the Equatorial Zone by an order of magnitude. The Great Red Spot shows a local maximum in the ammonia abundance. Ammonia abundance is highly correlated with temperature perturbations at the same altitude. Under the assumption that anomalies in ammonia and temperature are both perturbed from equilibrium by vertical motion, we find that the adjustment time constant for ammonia equilibration is about one third of the radiative time constant. (c) 2006 Elsevier Inc. All rights reserved. C1 Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Achterberg, RK (reprint author), NASA, Goddard Space Flight Ctr, Code 693, Greenbelt, MD 20771 USA. EM richard.k.achterberg@gsfc.nasa.gov NR 38 TC 22 Z9 22 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2006 VL 182 IS 1 BP 169 EP 180 DI 10.1016/j.icarus.2005.12.020 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 041CK UT WOS:000237430600011 ER PT J AU Spencer, JR Grundy, WM Dumas, C Carlson, RW McCord, TB Hansen, GB Terrile, RJ AF Spencer, JR Grundy, WM Dumas, C Carlson, RW McCord, TB Hansen, GB Terrile, RJ TI The nature of Europa's dark non-ice surface material: Spatially-resolved high spectral resolution spectroscopy from the Keck telescope SO ICARUS LA English DT Article DE satellites of Jupiter; Europa; surfaces, satellite; spectroscopy ID INFRARED MAPPING SPECTROMETER; HYDRATED SALT MINERALS; SUBSURFACE OCEAN; SULFURIC-ACID; GALILEO; FEATURES; DESIGN; ALBEDO; IO AB We present new 1.45-1.75 mu m spectra of Europa's dark non-ice material with a spectral resolution (lambda/delta lambda) of 1200, obtained by using adaptive optics on the Keck telescope to spatially separate the spectrum of the non-ice material from that of the surrounding ice-rich regions. Despite the great increase in spectral resolution over the previous best spectra of the non-ice material. taken with Galileo's near-infrared mapping spectrometer (NIMS) with lambda/delta lambda = 66, no new fine-scale spectral structure is revealed. The smoothness of the spectra is inconsistent with available laboratory spectra of crystalline hydrated salts at Europa temperatures, but is more consistent with various combinations of non-crystal line hydrated salts and/or hydrated Sulfuric acid, as have been matched to the lower-resolution NIMS spectra. (c) 2006 Elsevier Inc. All rights reserved. C1 Lowell Observ, Flagstaff, AZ 86001 USA. SW Res Inst, Dept Space Studies, Boulder, CO 80302 USA. European So Observ, Santiago, Chile. Jet Prop Lab, Pasadena, CA 91109 USA. Univ Hawaii, Planetary Sci Div, Hawaii Inst Geophys & Planetary Sci, Honolulu, HI 96822 USA. Univ Washington, Planetary Sci Inst, Seattle, WA 98195 USA. RP Spencer, JR (reprint author), Lowell Observ, 1400 W Mars Hill Rd, Flagstaff, AZ 86001 USA. EM spencer@boulder.swri.edu NR 28 TC 16 Z9 16 U1 0 U2 4 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2006 VL 182 IS 1 BP 202 EP 210 DI 10.1016/j.icarus.2005.12.024 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 041CK UT WOS:000237430600013 ER PT J AU Simon, D Simon, DL AF Simon, D. Simon, D. L. TI Kalman filtering with inequality constraints for turbofan engine health estimation SO IEE PROCEEDINGS-CONTROL THEORY AND APPLICATIONS LA English DT Article AB Kalman filters are often used to estimate the state variables of a dynamic system. However, in the application of Kalman filters some known signal information is often either ignored or dealt with heuristically. For instance, state-variable constraints (which may be based on physical considerations) are often neglected because they do not fit easily into the structure of the Kalman filter. Thus, two analytical methods to incorporate state-variable inequality constraints into the Kalman filter are now derived. The first method is a general technique that uses hard constraints to enforce inequalities on the state-variable estimates. The resultant filter is a combination of a standard Kalman filter and a quadratic programming problem. The second method uses soft constraints to estimate those state variables that are known to vary slowly with time. (Soft constraints are constraints that are required to be approximately satisfied rather than exactly satisfied.) The incorporation of state-variable constraints increases the computational effort of the filter but significantly improves its estimation accuracy. The improvement is proven theoretically and simulations are used to show that the proposed algorithms can provide an improved performance over unconstrained Kalman filtering. C1 Cleveland State Univ, Cleveland, OH 44115 USA. NASA, USA, Res Lab, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Simon, D (reprint author), Cleveland State Univ, Stilwell Hall,Room 332,1960 E 24th St, Cleveland, OH 44115 USA. EM dj.simon@csuohio.edu NR 28 TC 58 Z9 64 U1 2 U2 14 PU INST ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2379 J9 IEE P-CONTR THEOR AP JI IEE Proc.-Control Theory Appl. PD MAY PY 2006 VL 153 IS 3 BP 371 EP 378 DI 10.1049/ip-cta:20050074 PG 8 WC Automation & Control Systems; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Automation & Control Systems; Engineering; Instruments & Instrumentation GA 050RY UT WOS:000238106800016 ER PT J AU Hoque, MR Ahmad, T McNutt, TR Mantooth, HA Mojarradi, MM AF Hoque, MR Ahmad, T McNutt, TR Mantooth, HA Mojarradi, MM TI A technique to increase the efficiency of high-voltage charge pumps SO IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS LA English DT Article DE charge pump; charge transfer; dc-dc converter; dc-dc power conversion; silicon-on-insulator (SOI); voltage multiplier ID CIRCUITS AB A charge pump that utilizes a MOSFET body diode as a charge transfer switch is discussed. The body diode is characterized and a body diode model is developed for simulating the charge pump circuit. A 10% increase of voltage gain has been achieved in the proposed switching technique when compared with a traditional Dickson charge pump. The top plate and bottom plate switching technique have also been illustrated to improve the efficiency of the charge pump. A six-stage Dickson charge pump was designed to produce a 19 V output from a 3.3-V supply, using a 4 MHz, two-phase nonoverlapping clock signal driving the charge pump. The design was fabricated in a 0.35-mu m SOI CMOS process. An efficiency of 79% is achieved at a load current of approximately 19 mu A. C1 Univ Arkansas, Dept Elect Engn, Fayetteville, AR 72701 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Hoque, MR (reprint author), Univ Arkansas, Dept Elect Engn, Fayetteville, AR 72701 USA. EM mhoque@engr.uark.edu NR 6 TC 19 Z9 20 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1057-7130 J9 IEEE T CIRCUITS-II JI IEEE Trans. Circuits Syst. II-Express Briefs PD MAY PY 2006 VL 53 IS 5 BP 364 EP 368 DI 10.1109/TCSII.2006.869922 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA 047AR UT WOS:000237852700008 ER PT J AU Simon, MK AF Simon, MK TI On the bit-error probability of differentially encoded QPSK and offset QPSK in the presence of carrier synchronization SO IEEE TRANSACTIONS ON COMMUNICATIONS LA English DT Article DE bit-error probability (BEP); carrier synchronization; differentially encoded offset QPSK (DE-OQPSK); differentially encoded quadrature phase-shift keying (DE-QPSK) AB We investigate the differences between allowable differential encoding strategies and their associated bit-error probability performances for quadrature phase-shift keying (QPSK) and offset QPSK modulations when the carrier demodulation reference signals are supplied by the optimum (motivated by maximum a posteriori estimation of carrier phase) carrier-tracking loop suitable for that modulation. In particular, we show that in the presence of carrier-synchronization phase ambiguity but an otherwise ideal loop, both the symbol and bit-error probabilities in the presence of differential encoding are identical for the two modulations. On the other hand, when in addition the phase error introduced by the loop's finite signal-to-noise ratio is taken into account, it is shown that the two differentially encoded modulations behave differently, and their performances are no longer equivalent. A similar statement has previously been demonstrated for the same modulations when the phase ambiguity was assumed to have been perfectly resolved by means other than differential encoding. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Simon, MK (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM marvin.k.simon@jpl.nasa.gov NR 10 TC 8 Z9 8 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0090-6778 J9 IEEE T COMMUN JI IEEE Trans. Commun. PD MAY PY 2006 VL 54 IS 5 BP 806 EP 812 DI 10.1109/TCOMM.2006.874002 PG 7 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 047AP UT WOS:000237852500009 ER PT J AU Simon, MK Tkacenko, A AF Simon, MK Tkacenko, A TI Noncoherent data transition tracking loops for symbol synchronization in digital communication receivers SO IEEE TRANSACTIONS ON COMMUNICATIONS LA English DT Article DE data transition tracking loop (DTTL); noncoherent symbol sync loop; symbol synchronization AB Starting with the maximum a posteriori (MAP) estimation approach, this paper derives the optimum (in the MAP estimation sense) means for performing symbol-timing recovery in the absence of carrier-phase information (i.e., prior to carrier-phase recovery). Specifically, we examine the necessary modification of a well-known form of coherent symbol synchronizer, namely, the data transition tracking loop (DTTL), to allow its operation in the absence of carrier-phase information, i.e., as a so-called noncoherent symbol sync loop. By employing such a noncoherent scheme, one can eliminate the. need for iteration between the carrier and symbol sync functions, as typically takes place in receivers that more commonly perform carrier tracking and acquisition prior to symbol timing. The performance of both the linear and nonlinear versions of this noncoherent DTTL is obtained by a combination of analysis and simulation, and compared with that of the corresponding coherent DTTLs. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Simon, MK (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM marvin.k.simon@jpl.nasa.gov; andre.tkacenko@jpl.nasa.gov NR 6 TC 6 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0090-6778 J9 IEEE T COMMUN JI IEEE Trans. Commun. PD MAY PY 2006 VL 54 IS 5 BP 889 EP 899 DI 10.1109/TCOMM.2006.873984 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 047AP UT WOS:000237852500018 ER PT J AU Perhinschi, MG Napolitano, MR Campa, G Seanor, B Burken, J Larson, R AF Perhinschi, Mario G. Napolitano, Marcello R. Campa, Giampiero Seanor, Brad Burken, John Larson, Richard TI An adaptive threshold approach for the design of an actuator failure detection and identification scheme SO IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY LA English DT Article DE actuator failure detection; aicraft control; failure analysis; flight safety; neural network AB Typical logic schemes associated with failure detection and identification algorithms rely on a set of constant thresholds. The selection of the values for these thresholds is generally a tradeoff between the goals of maximizing failure detectability while minimizing false alarm rates. The main purpose of this brief is to propose an alternative to this conventional approach for defining the thresholds of a specific aircraft actuator failure detection and identification scheme. A specific set of detection and identification criteria for failures of the decoupled stabilators, canards, ailerons, and rudders of the NASA Advanced Control Technology for Integrated Vehicle F-15 aircraft have been formulated in terms of neural network estimates and correlation functions of the angular rates. The proposed scheme is based on the use of adaptive thresholds through the floating limiter concept. This new approach eliminates the need for parameter scheduling and has shown to be able to reduce the delays associated with the constant threshold method. The functionality of the approach has been illustrated through numerical simulations on the West Virginia University NASA Intelligent Flight Control System F-15 simulator. C1 W Virginia Univ, Dept Mech & Aerosp Engn, Morgantown, WV 26506 USA. NASA, Dryden Flight Res Ctr, Edwards AFB, CA 93523 USA. RP Perhinschi, MG (reprint author), W Virginia Univ, Dept Mech & Aerosp Engn, Morgantown, WV 26506 USA. EM Mario.Perhinschi@mail.wvu.edu NR 20 TC 17 Z9 18 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1063-6536 EI 1558-0865 J9 IEEE T CONTR SYST T JI IEEE Trans. Control Syst. Technol. PD MAY PY 2006 VL 14 IS 3 BP 519 EP 525 DI 10.1109/TCST.2005.860522 PG 7 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 043LX UT WOS:000237603700014 ER PT J AU Rajamani, V Bunting, CF Deshpande, MD Khan, ZA AF Rajamani, V Bunting, CF Deshpande, MD Khan, ZA TI Validation of Modal/MoM in shielding effectiveness studies of rectangular enclosures with apertures SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article DE FEKO; MoM; shielding effectiveness; validation ID PENETRATION AB This paper discusses the validation of Modal/method of moments (MoM) including cases when the apertures are made as big as the wall of the enclosure (equivalent to having one side of the cavity open). The validation is done using field computations involving bodies of arbitrary shape (FEKO), a commercially available code. The results show that Modal/MoM predicts the results close to the analytical results of Robinson et al. Electron. Lett., 32 (17), 1996; Robinson et al., IEEE Trans. Electromagn. Compat., 40 (3), 240-247, 1998 for single-aperture cases and for most double-aperture cases. Also, for the cases of considering oblique incident plane Waves, through validation, it has been found that Modal/MoM can predict the shielding effectiveness close to measured results for smaller angles and not for larger angles of incidence due to the edge effects. In this work, the shielding effectiveness is calculated at only one point, the center of the cavity assuming it to be the worst case. This work discovers the limitation of Modal/MoM for certain applications. C1 Oklahoma State Univ, Stillwater, OK 74078 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Ohio State Univ, Columbus, OH 43212 USA. RP Rajamani, V (reprint author), Oklahoma State Univ, Stillwater, OK 74078 USA. EM vignesh.rajamani@okstate.edu; reverb@okstate.edu; manohar.D.Deshpande@nasa.gov; khan.166@osu.edu RI Bunting, Charles/B-9762-2013 OI Bunting, Charles/0000-0001-9167-4235 NR 7 TC 25 Z9 30 U1 3 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD MAY PY 2006 VL 48 IS 2 BP 348 EP 353 DI 10.1109/TEMC.2006.873864 PG 6 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 048OJ UT WOS:000237956100012 ER PT J AU Schoeberl, MR Douglass, AR Hilsenrath, E AF Schoeberl, MR Douglass, AR Hilsenrath, E TI Foreword to the Special Issue on the EOS Aura Mission SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Editorial Material C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Schoeberl, MR (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. RI Douglass, Anne/D-4655-2012 NR 0 TC 1 Z9 1 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1063 EP 1064 DI 10.1109/TGRS.2006.871403 PG 2 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100001 ER PT J AU Schoeberl, MR Douglass, AR Hilsenrath, E Bhartia, PK Beer, R Waters, JW Gunson, MR Froidevaux, L Gille, JC Barnett, JJ Levelt, PE DeCola, P AF Schoeberl, MR Douglass, AR Hilsenrath, E Bhartia, PK Beer, R Waters, JW Gunson, MR Froidevaux, L Gille, JC Barnett, JJ Levelt, PE DeCola, P TI Overview of the EOS Aura Mission SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE atmospheric composition; Aura; Earth Observing Sytem (EOS); remote sensing; satellites ID TROPOSPHERIC WATER-VAPOR; MICROWAVE LIMB SOUNDER; UARS MLS; OZONE; SATELLITE; HIRDLS AB Aura, the last of the large Earth Observing System observatories, was launched on July 15, 2004. Aura is designed to make comprehensive stratospheric and tropospheric composition measurements from its four instruments, the High Resolution Dynamics Limb Sounder (HIRDLS), the Microwave Limb Sounder (MLS), the Ozone Monitoring Instrument (OMI), and the Tropospheric Emission Spectrometer (TES). With the exception of HIRDLS, all of the instruments are performing as expected, and HIRDLS will likely be able to deliver most of their planned data products. We summarize the mission, instruments, and synergies in this paper. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Colorado, Boulder, CO 80309 USA. Univ Oxford, Oxford OX1 2JD, England. Royal Dutch Meteorol Inst, KNMI, KSAS, NL-3730 AE De Bilt, Netherlands. NASA, Washington, DC 20546 USA. RP Schoeberl, MR (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM mark.r.schoeberl@nasa.gov RI Douglass, Anne/D-4655-2012; Bhartia, Pawan/A-4209-2016 OI Bhartia, Pawan/0000-0001-8307-9137 NR 22 TC 184 Z9 194 U1 2 U2 26 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1066 EP 1074 DI 10.1109/TGRS.2005.861950 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100002 ER PT J AU Waters, JW Froidevaux, L Harwood, RS Jarnot, RF Pickett, HM Read, WG Siegel, PH Cofield, RE Filipiak, MJ Flower, DA Holden, JR Lau, GKK Livesey, NJ Manney, GL Pumphrey, HC Santee, ML Wu, DL Cuddy, DT Lay, RR Loo, MS Perun, VS Schwartz, MJ Stek, PC Thurstans, RP Boyles, MA Chandra, KM Chavez, MC Chen, GS Chudasama, BV Dodge, R Fuller, RA Girard, MA Jiang, JH Jiang, YB Knosp, BW LaBelle, RC Lam, JC Lee, KA Miller, D Oswald, JE Patel, NC Pukala, DM Quintero, O Scaff, DM Van Snyder, W Tope, MC Wagner, PA Walch, MJ AF Waters, JW Froidevaux, L Harwood, RS Jarnot, RF Pickett, HM Read, WG Siegel, PH Cofield, RE Filipiak, MJ Flower, DA Holden, JR Lau, GKK Livesey, NJ Manney, GL Pumphrey, HC Santee, ML Wu, DL Cuddy, DT Lay, RR Loo, MS Perun, VS Schwartz, MJ Stek, PC Thurstans, RP Boyles, MA Chandra, KM Chavez, MC Chen, GS Chudasama, BV Dodge, R Fuller, RA Girard, MA Jiang, JH Jiang, YB Knosp, BW LaBelle, RC Lam, JC Lee, KA Miller, D Oswald, JE Patel, NC Pukala, DM Quintero, O Scaff, DM Van Snyder, W Tope, MC Wagner, PA Walch, MJ TI The Earth Observing System Microwave Limb Sounder (EOS MLS) on the Aura satellite SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE microwave; remote sensing; stratosphere; submitlimeter wave ID ATMOSPHERE RESEARCH SATELLITE; PRESSURE-INDUCED LINESHAPE; CLOUD ICE MEASUREMENTS; GRAVITY-WAVES; WATER-VAPOR; OZONE; CALIBRATION; UARS; STRATOSPHERE; VALIDATION AB The Earth Observing System Microwave Limb Sounder measures several atmospheric chemical species (OH, HO2, H2O, O-3, HCl, ClO, HOCl, BrO, HNO3, N2O, CO, HCN, CH3CN, volcanic SO2), cloud ice, temperature, and geopotential height to improve our understanding of stratospheric ozone chemistry, the interaction of composition and climate, and pollution in the upper troposphere. All measurements are made simultaneously and continuously, during both day and night. The instrument uses heterodyne radiometers that observe thermal emission from the atmospheric limb in broad spectral regions centered near 118, 190, 240, and 640 GHz, and 2.5 THz. It was launched July 15, 2004 on the National Aeronautics and Space Administration's Aura satellite and started full-up science operations on August 13, 2004. An atmospheric limb scan and radiometric calibration for all bands are performed routinely every 25 s. Vertical profiles are retrieved every 165 km along the suborbital track, covering 82 degrees S to 82 degrees N latitudes on each orbit. Instrument performance to date has been excellent; data have been made publicly available; and initial science results have been obtained. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. RP Waters, JW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM joe@mls.jpl.nasa.gov RI Schwartz, Michael/F-5172-2016; Wu, Dong/D-5375-2012 OI Schwartz, Michael/0000-0001-6169-5094; NR 61 TC 521 Z9 535 U1 7 U2 50 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 EI 1558-0644 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1075 EP 1092 DI 10.1109/TGRS.2006.873771 PG 18 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100003 ER PT J AU Beer, R AF Beer, R TI TES on the Aura mission: Scientific objectives, measurements, and analysis overview SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE chemistry; Fourier spectroscopy; infrared spectroscopy; ozone; remote sensing; terrestrial atmosphere ID SATELLITE AB The Tropospheric Emission Spectrometer (TES) is a high-resolution infrared imaging Fourier transform spectrometer specifically aimed at determining the chemical state of the Earth's lower atmosphere (the troposphere). In particular, TES produces vertical profiles 0-32 km of important pollutant and greenhouse gases such as carbon monoxide, ozone, methane, and water vapor on a global scale every other day. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Beer, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Reinhard.Beer@jpl.nasa.gov NR 16 TC 141 Z9 145 U1 0 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1102 EP 1105 DI 10.1109/TGRS.2005.863716 PG 4 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100005 ER PT J AU Froidevaux, L Livesey, NJ Read, WG Jiang, YBB Jimenez, C Filipiak, MJ Schwartz, MJ Santee, ML Pumphrey, HC Jiang, JH Wu, DL Manney, GL Drouin, BJ Waters, JW Fetzer, EJ Bernath, PF Boone, CD Walker, KA Jucks, KW Toon, GC Margitan, JJ Sen, B Webster, CR Christensen, LE Elkins, JW Atlas, E Lueb, RA Hendershot, R AF Froidevaux, L Livesey, NJ Read, WG Jiang, YBB Jimenez, C Filipiak, MJ Schwartz, MJ Santee, ML Pumphrey, HC Jiang, JH Wu, DL Manney, GL Drouin, BJ Waters, JW Fetzer, EJ Bernath, PF Boone, CD Walker, KA Jucks, KW Toon, GC Margitan, JJ Sen, B Webster, CR Christensen, LE Elkins, JW Atlas, E Lueb, RA Hendershot, R TI Early validation analyses of atmospheric profiles from EOS MLS on the Aura satellite SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE atmospheric retrievals; data validation ID HALOGEN OCCULTATION EXPERIMENT; DATA SET; SPECTROMETER; AIRS/AMSU/HSB; BALLOON; SYSTEM AB We present results of early validation studies using retrieved atmospheric profiles from the Earth Observing System Microwave Limb Sounder (MLS) instrument on the Aura satellite. "Global" results are presented for MLS measurements of atmospheric temperature, ozone, water vapor, hydrogen chloride, nitrous oxide, nitric acid, and carbon monoxide, with a focus on the January-March 2005 time period. These global comparisons are made using long-standing global satellites and meteorological datasets, as well as some measurements from more recently launched satellites. Comparisons of MLS data with measurements from the Ft. Sumner, NM, September 2004 balloon flights are also presented. Overall, good agreement is obtained, often within 5% to 10%, but we point out certain issues to resolve and some larger systematic differences; some artifacts in the first publicly released MLS (version 1.5) dataset are noted. We comment briefly on future plans for validation and software improvements. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Edinburgh EH9 3JN, Midlothian, Scotland. Univ Waterloo, Waterloo, ON N2L 3G1, Canada. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Ocean & Atmospher Adm, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. Univ Miami, Miami, FL 33149 USA. Natl Ctr Atmospher Res, Boulder, CO 80303 USA. New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM lucien@mls.jpl.nasa.gov RI Bernath, Peter/B-6567-2012; Atlas, Elliot/J-8171-2015; Schwartz, Michael/F-5172-2016; Wu, Dong/D-5375-2012 OI Bernath, Peter/0000-0002-1255-396X; Schwartz, Michael/0000-0001-6169-5094; NR 45 TC 168 Z9 170 U1 2 U2 14 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 EI 1558-0644 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1106 EP 1121 DI 10.1109/TGRS.2006.864366 PG 16 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100006 ER PT J AU Pickett, HM AF Pickett, HM TI Microwave Limb Sounder THz module on Aura SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE mesosphere; OH; stratosphere; THz ID OH AB The objective of the Microwave Limb Sounder THz module on the Aura satellite is to measure stratospheric and meso- spheric OH. This paper describes the optical design, alignment, calibration, and performance of the THz module. The calibration uncertainty for one limb scan is substantially less than the precision due to radiometric noise. For averages of many scans, the dominant calibration uncertainty of 2% is due to uncertainty in beam efficiency. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pickett, HM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM herbert.m.pickett@jpl.nasa.gov NR 9 TC 26 Z9 29 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1122 EP 1130 DI 10.1109/TGRS.2005.862667 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100007 ER PT J AU Jarnot, RF Perun, VS Schwartz, MJ AF Jarnot, RF Perun, VS Schwartz, MJ TI Radiometric and spectral performance and calibration of the GHz bands of EOS MLS SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE calibration; GHz; limb sounding; microwave; submillimeter wave ID ATMOSPHERE RESEARCH SATELLITE; MICROWAVE LIMB SOUNDER AB This paper describes radiometric performance and prelaunch radiometric and spectral calibrations of the GHz component of the Microwave Limb Sounder (MLS) experiment on NASA's Aura spacecraft. Estimated systematic scaling uncertainties (3 sigma) on limb port radiances are similar to 0.5% from radiometric calibration and similar to 0.5% to similar to 1% from spectral calibrations. Operational noise performance is consistent with prelaunch expectations, and in-orbit measurements to date indicate no changes in noise characteristics, and no observable calibration drifts. Spectral baseline has remained stable to similar to 20 mK since launch. Refinements to calibrations based on in-flight data are discussed, and radiometric calibration algorithms are described. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Jarnot, RF (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Robert.F.Jarnot@jpl.nasa.gov RI Schwartz, Michael/F-5172-2016 OI Schwartz, Michael/0000-0001-6169-5094 NR 13 TC 25 Z9 28 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1131 EP 1143 DI 10.1109/TGRS.2005.863714 PG 13 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100008 ER PT J AU Livesey, NJ Van Snyder, W Read, WG Wagner, PA AF Livesey, NJ Van Snyder, W Read, WG Wagner, PA TI Retrieval algorithms for the EOS Microwave Limb Sounder (MLS) SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE atmospheric measurements; inverse problems; millimeterwave measurements; remote sensing; terrestrial atmosphere ID UARS AB The retrieval algorithms for the Earth Observing System Microwave Limb Sounder (MLS) on the Aura spacecraft, launched on July 15, 2004, are described. These algorithms are used to produce estimates of geophysical parameters such as vertical profiles of atmospheric temperature and composition ("Level 2" data) from the calibrated MLS observations of microwave limb radiance ("Level 1" data). The MLS algorithms are based on the standard optimal estimation approach, a weighted nonlinear least squares optimization with a priori constraints. New aspects include adaptation to a two-dimensional system, and an approach to the issues of retrieval "phasing" and error propagation that differs from that taken for previous similar instruments. Important new aspects of the software that implements these algorithms are also described, along with the algorithm configuration for the "version 1.5" dataset. Some examples are shown from MLS in-orbit observations. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Livesey, NJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM livesey@mls.jpl.nasa.gov NR 15 TC 132 Z9 135 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1144 EP 1155 DI 10.1109/TGRS.2006.872327 PG 12 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100009 ER PT J AU Wu, DL Jiang, JH Davis, CP AF Wu, DL Jiang, JH Davis, CP TI EOS MLS cloud ice measurements and cloudy-sky radiative transfer model SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE ice water content (IWC); limb sounding; microwave; polarization; satellite; upper-tropospheric clouds ID CLIMATE; PRODUCTS; CRYSTALS; MISSION; EARTH AB A cloud ice retrieval technique is described here using measurements at frequencies near 118, 190, 240, and 640 GHz and 2.5 THz from the Earth Observing System Microwave Limb Sounder on the NASA Aura satellite. Measurement principles, methods for cloud detection, and radiative transfer models for retrieving cloud properties are discussed. The 240-GHz data from high-tangent heights are used to retrieve ice water content at pressures < 215 hPa, and the 118-, 190-, 240-, and 640-GHz radiances from low-tangent heights are used to retrieve ice water paths with different penetration depths. Some early Microwave Limb Sounder (MLS) results are highlighted, and the observed cloud signatures are consistent with the expectation from model simulations, in general. The simultaneous measurements from MLS 240 and 640 GHz radiometers contain useful information on particle sizes. There are significant cloud-induced radiances at 2.5 THz, despite strong attenuation from the atmosphere. Cloud-scattering signatures are polarized at 122 GHz, but the polarization differences are typically less than 10% of the total cloud-induced radiance. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Sch Geosci, Inst Atmospher & Environm Sci, Edinburgh EH9 3JZ, Midlothian, Scotland. RP Wu, DL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM dong.l.wu@jpl.nasa.gov; jonathan.h.jiang@jpl.nasa.gov; cdavis@staffmail.ed.ac.uk RI Wu, Dong/D-5375-2012 NR 30 TC 49 Z9 50 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1156 EP 1165 DI 10.1109/TGRS.2006.869994 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100010 ER PT J AU Cofield, RE Stek, PC AF Cofield, RE Stek, PC TI Design and field-of-view calibration of 114-660-GHz optics of the Earth Observing System Microwave Limb Sounder SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE calibration; microwave optics; near-field range; remote sensing ID ATMOSPHERE RESEARCH SATELLITE AB This paper describes the optics design and field-of-view (FOV) calibration for five radiometers covering 114-660 GHz which share a common antenna in the Microwave Limb Sounder instrument on the National Aeronautics and Space Administration's Aura satellite. Details of near-field pattern measurements are presented. Estimated systematic scaling uncertainties (3 sigma) on calibrated limb emissions, due to FOV calibration uncertainties, are below 0.4%. 3 sigma uncertainties in beamwidth and relative pointing of radiometer boresights are 0.006 degrees and 0.003 degrees, respectively. The uncertainty in modeled instrument response, due to the scan dependence of FOV patterns, is less than 0.24 K equivalent blackbody temperature. Refinements to the calibration using in-flight data are presented. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Cofield, RE (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Richard.E.Cofield@jpl.nasa.gov NR 19 TC 25 Z9 26 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1166 EP 1181 DI 10.1109/TGRS.2006.873234 PG 16 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100011 ER PT J AU Schwartz, MJ Read, WG Van Snyder, W AF Schwartz, MJ Read, WG Van Snyder, W TI EOS MLS forward model polarized radiative transfer for Zeeman-split oxygen lines SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE Earth Observing System (EOS) Aura; forward model; Microwave Limb Sounder (MLS); Zeeman ID DEPENDENCE; FIELD AB This work supplements the Earth Observing System (EOS) Microwave Limb Sounder (MLS) clear-sky unpolarized forward model with algorithms for modeling polarized emission from the Zeeman-split 118.75-GHz O-2 spectral line. The model accounts for polarization-dependent emission and for correlation between polarizations with complex, 2 x 2 intensity and absorption matrices. The oxygen line is split into three Zeeman components by the interaction of oxygen's electronic spin with an external magnetic field, and the splitting is of order 0.5 MHz in a typical geomagnetic field. Zeeman splitting is only significant at pressures low enough that collisional broadening (similar to 1.6 MHz/hPa) is not very large by comparison. The polarized forward model becomes significant for MLS temperature retrievals at pressure below 1.0 hPa and is crucial at pressures below similar to 0.03 hPa. Interaction of the O-2 Molecule with the radiation field depends upon the relative orientation of the radiation polarization mode and the geomagnetic field direction. The model provides both limb radiances and the derivatives of these radiances with respect to atmospheric temperature and composition, as required by MLS temperature retrievals. EOS MLS views the atmospheric limb at 118.75 GHz with a pair of linear-cross-polarized, 100-kHz-resolution, 10-MHz-wide spectrometers. The antennas of the associated receivers are scanned to view rays with tangent heights from the Earth's surface to 0.001 hPa. Comparisons of the modeled MLS radiances with measurements show generally good agreement in line positions and strengths, however residuals in the line centers at the highest tangent heights are larger than desired and still under investigation. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Schwartz, MJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Michael.J.Schwartz@jpl.nasa.gov RI Schwartz, Michael/F-5172-2016 OI Schwartz, Michael/0000-0001-6169-5094 NR 21 TC 18 Z9 19 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1182 EP 1191 DI 10.1109/TGRS.2005.862267 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100012 ER PT J AU Cuddy, DT Echeverri, MD Wagner, PA Hanzel, AT Fuller, RA AF Cuddy, DT Echeverri, MD Wagner, PA Hanzel, AT Fuller, RA TI EOS MLS science data processing system: A description of architecture and capabilities SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE computer facilities; data handling; data processing AB The Earth Observing System (EOS) Microwave Limb Sounder (MLS) is an atmospheric remote sensing experiment led by the Jet Propulsion Laboratory of the California Institute of Technology. The objectives of the EOS MLS are to learn more about stratospheric chemistry and causes of ozone changes, processes affecting climate variability, and pollution in the upper troposphere. The EOS MLS is one of four instruments on the National Aeronautics and Space Administration (NASA) FOS Aura spacecraft launched on July 15, 2004, with an operational period extending at least 5 years after launch. This paper describes the architecture and capabilities of the Science Data Processing System (SDPS) for the FOS MLS. The SDPS consists of two major components-the Science Computing Facility and the Science Investigator-led Processing System. The Science Computing Facility provides the facilities for the EOS MLS Science Team to perform the functions of scientific algorithm development, processing software development, quality control of data products, and scientific analyses. The Science Investigator-led Processing System processes and reprocesses the science data for the entire mission and delivers the data products to the Science Computing Facility and to the Goddard Space Flight Center Earth Science Distributed Active Archive Center, which archives and distributes the standard science products. The Science Investigator-led Processing System is developed and operated by Raytheon Information Technology and Scientific Services of Pasadena under contract with Jet Propulsion Laboratory. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Raytheon Informat Technol & Sci Serv, Pasadena, CA 91101 USA. RP Cuddy, DT (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM david.t.cuddy@jpl.nasa.gov NR 13 TC 5 Z9 6 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1192 EP 1198 DI 10.1109/TGRS.2005.863712 PG 7 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100013 ER PT J AU Levelt, PF Hilsenrath, E Leppelmeier, GW van den Oord, GHJ Bhartia, PK Tamminen, J de Haan, JF Veefkind, JP AF Levelt, PF Hilsenrath, E Leppelmeier, GW van den Oord, GHJ Bhartia, PK Tamminen, J de Haan, JF Veefkind, JP TI Science objectives of the Ozone Monitoring Instrument SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE air quality; atmospheric composition; ozone monitoring; satellite measurements AB The Ozone Monitoring Instrument (OMI) flies on NASA's Earth Observing System AURA satellite, launched in July 2004. OMI is an ultraviolet/visible (UV/VIS) nadir solar backscatter spectrometer, which provides nearly global coverage in one day, with a spatial resolution of 13 km x 24 km. Trace gases measured include O-3, NO2, SO2, HCHO, BrO, and OClO. In addition OMI measures aerosol characteristics, cloud top heights and cloud coverage, and UV irradiance at the surface. OMI's unique capabilities for measuring important trace gases with daily global coverage and a small footprint will make a major contribution to our understanding of stratospheric and tropospheric chemistry and climate change along with Aura's other three instruments. OMI's high spatial resolution enables detection of air pollution at urban scales. Total Ozone Mapping Spectrometer and differential optical absorption spectroscopy heritage algorithms, as well as new ones developed by the international (Dutch, Finnish, and U.S.) OMI science team, are used to derive OMI's advanced backscatter data products. In addition to providing data for Aura's prime objectives, OMI will provide near-real-time data for operational agencies in Europe and the U.S. Examples of OMI's unique capabilities are presented in this paper. C1 Royal Dutch Meteorol Inst, KNMI, KSAS, NL-3730 AE De Bilt, Netherlands. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. G&S Associates Oy, Espoo 02360, Finland. Finnish Meteorol Inst, Earth Observat, FIN-00101 Helsinki, Finland. RP Levelt, PF (reprint author), Royal Dutch Meteorol Inst, KNMI, KSAS, NL-3730 AE De Bilt, Netherlands. EM levelt@knmi.nl; Ernest.Hilsenrath@nasa.gov; gwl@GandS.pp.fi; oordvd@knmi.nl; Pawan.Bhartia@nasa.gov; Johanna.Tamminen@fmi.fi; haandej@knmi.nl; veefkind@knmi.nl RI Tamminen, Johanna/D-7959-2014; Bhartia, Pawan/A-4209-2016 OI Tamminen, Johanna/0000-0003-3095-0069; Bhartia, Pawan/0000-0001-8307-9137 NR 28 TC 190 Z9 195 U1 2 U2 25 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1199 EP 1208 DI 10.1109/TGRS.2006.872336 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100014 ER PT J AU Dobber, MR Dirksen, RJ Levelt, PF Van den Oord, GHJ Voors, RHM Kleipool, Q Jaross, G Kowalewski, M Hilsenrath, E Leppelmeier, GW de Vries, J Dierssen, W Rozemeijer, NC AF Dobber, MR Dirksen, RJ Levelt, PF Van den Oord, GHJ Voors, RHM Kleipool, Q Jaross, G Kowalewski, M Hilsenrath, E Leppelmeier, GW de Vries, J Dierssen, W Rozemeijer, NC TI Ozone-Monitoring Instrument calibration SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE calibration; charge coupled device (CCD); remote sensing; ultraviolet spectroscopy ID RANDOM TELEGRAPH SIGNALS; PROTON-IRRADIATED CCDS AB The Ozone Monitoring Instrument (OMI) was launched on July 15, 2004 on the National Aeronautics and Space Administration's Earth Observing System Aura satellite. The OMI instrument is an ultraviolet-visible imaging spectrograph that uses two-dimensional charge-coupled device detectors to register both the spectrum and the swath perpendicular to the flight direction with a 115 degrees wide swath, which enables global daily ground coverage with high spatial resolution. This paper presents the OMI design and discusses the main performance and calibration features and results. C1 Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. Space Res Org Netherlands, NL-3584 CA Utrecht, Netherlands. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. G&S Assoc Oy, Espoo 02360, Finland. Dutch Space BV, NL-2303 DB Leiden, Netherlands. TriOpSys BV, NL-3605 JW Maarssen, Netherlands. RP Dobber, MR (reprint author), Royal Netherlands Meteorol Inst, POB 201, NL-3730 AE De Bilt, Netherlands. EM dobber@knmi.nl; Ernest.Hilsenrath@nasa.gov; gwl@GandS.pp.fi NR 19 TC 57 Z9 60 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1209 EP 1238 DI 10.1109/TGRS.2006.869987 PG 30 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100015 ER PT J AU Bucsela, EJ Celarier, EA Wenig, MO Gleason, JF Veefkind, JP Boersma, KF Brinksma, EJ AF Bucsela, EJ Celarier, EA Wenig, MO Gleason, JF Veefkind, JP Boersma, KF Brinksma, EJ TI Algorithm for NO2 vertical column retrieval from the ozone monitoring instrument SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE algorithm; nitrogen dioxide (NO2); Ozone Monitoring Instrument (OMI); troposphere ID ROTATIONAL RAMAN-SCATTERING; BACKSCATTER ULTRAVIOLET MEASUREMENTS; STRATOSPHERIC NO2; GOME MEASUREMENTS; TROPOSPHERIC NO2; ABSORPTION SPECTROSCOPY; NITROGEN-DIOXIDE; ATMOSPHERE; MODEL; DISTRIBUTIONS AB We describe the operational algorithm for the retrieval of stratospheric, tropospheric, and total column densities of nitrogen dioxide (NO2) from earthshine radiances measured by the Ozone Monitoring Instrument (OMI), aboard the EOS-Aura satellite. The algorithm uses the DOAS method for the retrieval of slant column NO2 densities. Air mass factors (AMFs) calculated from a stratospheric NO2 profile are used to make initial estimates of the vertical column density. Using data collected over a 24-h period, a smooth estimate of the global stratospheric field is constructed. Where the initial vertical column densities exceed the estimated stratospheric field, we infer the presence of tropospheric NO2, and recalculate the vertical column density (VCD) using an AMF calculated from an assumed tropospheric NO2 profile. The parameters that control the operational algorithm were selected with the aid of a set of data assembled from stratospheric and tropospheric chemical transport models. We apply the optimized algorithm to OMI data and present global maps of NO2 VCDs for the first time. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Royal Netherlands Meteorol Inst, De Bilt, Netherlands. RP Bucsela, EJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM eric.bucsela@gsfc.nasa.gov; veefkind@knmi.nl RI Gleason, James/E-1421-2012; Boersma, Klaas/H-4559-2012; Pfister, Gabriele/A-9349-2008 OI Boersma, Klaas/0000-0002-4591-7635; NR 45 TC 150 Z9 155 U1 0 U2 15 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 EI 1558-0644 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1245 EP 1258 DI 10.1109/TGRS.2005.863715 PG 14 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100017 ER PT J AU Krotkov, NA Carn, SA Krueger, AJ Bhartia, PK Yang, K AF Krotkov, NA Carn, SA Krueger, AJ Bhartia, PK Yang, K TI Band residual difference algorithm for retrieval of SO2 from the aura Ozone Monitoring Instrument (OMI) SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE anthropogenic pollution; aura; Ozone Monitoring Instrument (OMI); SO2; volcanic degassing ID SULFUR-DIOXIDE; CLOUDS; GOME AB The Ozone Monitoring Instrument (OMI) on EOS/Aura offers unprecedented spatial and spectral resolution, coupled with global coverage, for space-based UV measurements of sulfur dioxide (SO2). This paper describes an OMI SO2 algorithm (the band residual difference) that uses calibrated residuals at SO2 absorption band centers produced by the NASA operational ozone algorithm (OMTO3). By using optimum wavelengths for retrieval of SO2, the retrieval sensitivity is improved over NASA predecessor Total Ozone Mapping Spectrometer (TOMS) by factors of 10 to 20, depending on location. The ground footprint of OMI is eight times smaller than TOMS. These factors produce two orders of magnitude improvement in the minimum detectable mass Of SO2. Thus, the diffuse boundaries of volcanic clouds can be imaged better and the clouds can be tracked longer. More significantly, the improved sensitivity now permits daily global measurement of passive volcanic degassing of SO2 and of heavy anthropogenic SO2 pollution to provide new information on the relative importance of these sources for climate studies. C1 Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21250 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Krotkov, NA (reprint author), Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. EM krotkov@chescat.gsfc.nasa.gov; scarn@umbc.edu; akrueger@umbc.edu; Pawan.Bhartia@nasa.gov; Kai.Yang.1@gsfc.nasa.gov RI Krotkov, Nickolay/E-1541-2012; Bhartia, Pawan/A-4209-2016 OI Krotkov, Nickolay/0000-0001-6170-6750; Bhartia, Pawan/0000-0001-8307-9137 NR 30 TC 155 Z9 167 U1 2 U2 30 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1259 EP 1266 DI 10.1109/TGRS.2005.861932 PG 8 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100018 ER PT J AU Tanskanen, A Krotkov, NA Herman, JR Arola, A AF Tanskanen, A Krotkov, NA Herman, JR Arola, A TI Surface ultraviolet irradiance from OMI SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE algorithms; software verification and validation; solar radiation; ultraviolet radiation effects ID SATELLITE ESTIMATION; UV IRRADIANCE; TOTAL OZONE; AEROSOLS AB The Ozone Monitoring Instrument (OMI) onboard the NASA Earth Observing System (EOS) Aura spacecraft is a nadir-viewing spectrometer that measures solar reflected and backscattered light in a selected range of the ultraviolet and visible spectrum. The instrument has a 2600-km-wide viewing swath, and it is capable of daily, global contiguous mapping. We developed and implemented a surface ultraviolet (UV) irradiance algorithm for OMI that produces noontime surface spectral UV irradiance estimates at four wavelengths (305, 310, 324, and 380 nm). Additionally, noontime erythemal dose rate and the erythemal daily dose are estimated. The OMI surface UV algorithm inherits from the surface UV algorithm developed by NASA Goddard Space Flight Center for the Total Ozone Mapping Spectrometer (TOMS). The OMI surface UV irradiance products are produced and archived in HDF5-EOS format by Finnish Meteorological Institute. The accuracy of the surface UV estimates depend on UV wavelength and atmospheric and other geolocation specific conditions ranging from 7% to 30%. A postprocessing aerosol correction can be applied at sites with additional ground-based measurements of the aerosol absorption optical thickness. The current OMI surface UV product validation plan is presented. C1 Finnish Meteorol Inst, FIN-00101 Helsinki, Finland. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Tanskanen, A (reprint author), Finnish Meteorol Inst, FIN-00101 Helsinki, Finland. EM aapo.tanskanen@fmi.fi RI Krotkov, Nickolay/E-1541-2012; OI Krotkov, Nickolay/0000-0001-6170-6750; Herman, Jay/0000-0002-9146-1632; Arola, Antti/0000-0002-9220-0194 NR 13 TC 45 Z9 46 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1267 EP 1271 DI 10.1109/TGRS.2005.862203 PG 5 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100019 ER PT J AU Joiner, J Vasilkov, AP AF Joiner, J Vasilkov, AP TI First results from the OMI rotational Raman scattering cloud pressure algorithm SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE cloud; Raman; retrieval; scattering ID BACKSCATTER ULTRAVIOLET MEASUREMENTS; OZONE MONITORING EXPERIMENT; SATELLITE MEASUREMENTS; MODIS; RETRIEVAL; PROFILES; OXYGEN; WATER; BAND AB We have developed an algorithm to retrieve scattering cloud pressures and other cloud properties with the Aura Ozone Monitoring Instrument (OMI). The scattering cloud pressure is retrieved using the effects of rotational Raman scattering (RRS). It is defined as the pressure of a Lambertian surface that would produce the observed amount of RRS consistent with the derived reflectivity of that surface. The independent pixel approximation is used in conjunction with the Lambertian-equivalent reflectivity model to provide an effective radiative cloud fraction and scattering pressure in the presence of broken or thin cloud. The derived cloud pressures will enable accurate retrievals of trace gas mixing ratios, including ozone, in the troposphere within and above clouds. We describe details of the algorithm that will be used for the first release of these products. We compare our scattering cloud pressures with cloud-top pressures and other cloud properties from the Aqua Moderate-Resolution Imaging Spectroradiometer (MODIS) instrument. OMI and MODIS are part of the so-called A-train satellites flying in formation within 30 min of each other. Differences between OMI and MODIS are expected because the MODIS observations in the thermal infrared are more sensitive to the cloud top whereas the backscattered photons in the ultraviolet can penetrate deeper into clouds. Radiative transfer calculations are consistent with the observed differences. The OMI cloud pressures are shown to be correlated with the cirrus reflectance. This relationship indicates that OMI can probe through thin or moderately thick cirrus to lower lying water clouds. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Joiner, J (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM joanna.joiner@nasa.gov RI Joiner, Joanna/D-6264-2012 NR 31 TC 52 Z9 52 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1272 EP 1282 DI 10.1109/TGRS.2005.861385 PG 11 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100020 ER PT J AU Worden, H Beer, R Bowman, KW Fisher, B Luo, M Rider, D Sarkissian, E Tremblay, D Zong, J AF Worden, H Beer, R Bowman, KW Fisher, B Luo, M Rider, D Sarkissian, E Tremblay, D Zong, J TI TES level 1 algorithms: Interferogram processing, geolocation, radiometric, and spectral calibration SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE Aura; Earth Observing System (EOS); Fourier Transform Spectrometry (FTS); infrared remote sensing; radiometric calibration; Tropospheric Emission Spectrometer (TES) ID ATMOSPHERIC INFRARED SOUNDER; AIRS; SPECTROSCOPY; SPECTROMETRY; TRANSFORM; PRELAUNCH AB The Tropospheric Emission Spectromter (TES) on the Earth Observing System (EOS) Aura satellite measures the infrared radiance emitted by the Earth's surface and atmosphere using Fourier transform spectrometry. The measured interferograms are converted into geolocated, calibrated radiance spectra by the L1 (Level 1) processing, and are the inputs to L2 (Level 2) retrievals of atmospheric parameters, such as vertical profiles of trace gas abundance. We describe the algorithmic components of TES Level 1 processing, giving examples of the intermediate results and diagnostics that are necessary for creating TES L1 products. An assessment of noise-equivalent spectral radiance levels and current systematic errors is provided. As an initial validation of our spectral radiances, TES data are compared to the Atmospheric Infrared Sounder (AIRS) (on EOS Aqua), after accounting for spectral resolution differences by applying the AIRS spectral response function to the TES spectra. For the TES L1 nadir data products currently available, the agreement with AIRS is 1 K or better. C1 Jet Prop Lab, Pasadena, CA 91109 USA. Raytheon ITSS, Pasadena, CA 91101 USA. RP Worden, H (reprint author), Jet Prop Lab, Pasadena, CA 91109 USA. EM Helen.Worden@jpl.nasa.gov NR 20 TC 22 Z9 22 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1288 EP 1296 DI 10.1109/TGRS.2005.863717 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100022 ER PT J AU Bowman, KW Rodgers, CD Kulawik, SS Worden, J Sarkissian, E Osterman, G Steck, T Lou, M Eldering, A Shephard, M Worden, H Lampel, M Clough, S Brown, P Rinsland, C Gunson, M Beer, R AF Bowman, KW Rodgers, CD Kulawik, SS Worden, J Sarkissian, E Osterman, G Steck, T Lou, M Eldering, A Shephard, M Worden, H Lampel, M Clough, S Brown, P Rinsland, C Gunson, M Beer, R TI Tropospheric emission spectrometer: Retrieval method and error analysis SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE atmospheres; constituents; inverse methods; remote sounding; temperature ID SPECTRAL RADIANCES; OZONE; SIMULATIONS; SELECTION; SPACE AB We describe the approach for the estimation of the atmospheric state, e.g., temperature, water, ozone, from calibrated, spectral radiances measured from the Tropospheric Emission Spectrometer (TES) onboard the Aura spacecraft. The methodology is based on the maximum a posteriori estimate, which mathematically requires the minimization of the difference between observed spectral radiances and a nonlinear model of radiative transfer of the atmospheric state subject to the constraint that the estimated state must be consistent with an a priori probability distribution for that state. The minimization techniques employed here are based on the trust-region Levenberg-Marquardt algorithm. An analysis of the errors for this estimate include smoothing, random, spectroscopic, "cross-state," representation, and systematic errors. In addition, several metrics and diagnostics are introduced that assess the resolution, quality, and statistical significance of the retrievals. We illustrate this methodology for the retrieval of atmospheric and surface temperature, water vapor, and ozone over the Gulf of Mexico on November 3, 2004. C1 Jet Prop Lab, Pasadena, CA 91109 USA. Univ Oxford, Dept Phys, Oxford OX1 2JD, England. Forschungszentrum Karlsruhe, Inst Meterol & Klimaforsch, D-76021 Karlsruhe, Germany. Atmospher & Environm Res Inc, Lexington, MA 02421 USA. Raytheon ITSS, Pasadena, CA 91101 USA. Hartford Financial Serv, Hartford, CT 06115 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Jet Prop Lab, Pasadena, CA 91109 USA. EM kevin.bowman@.jpl.nasa.gov NR 28 TC 146 Z9 148 U1 2 U2 15 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 EI 1558-0644 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1297 EP 1307 DI 10.1109/TGRS.2006871234 PG 11 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100023 ER PT J AU Clough, SA Shephard, MW Worden, J Brown, PD Worden, HM Luo, M Rodgers, CD Rinsland, CP Goldman, A Brown, L Kulawik, SS Eldering, A Lampel, M Osterman, G Beer, R Bowman, K Cady-Pereira, KE Mlawer, EJ AF Clough, SA Shephard, MW Worden, J Brown, PD Worden, HM Luo, M Rodgers, CD Rinsland, CP Goldman, A Brown, L Kulawik, SS Eldering, A Lampel, M Osterman, G Beer, R Bowman, K Cady-Pereira, KE Mlawer, EJ TI Forward model and Jacobians for Tropospheric Emission Spectrometer retrievals SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE earth limb and nadir operational retrieval (ELANOR); forward model; Jacobians; line-by-line radiation transfer modeling (LBLRTM); radiative transfer (RT); TES; Tropospheric Emission Spectrometer (TES) ID ABSORPTION CROSS-SECTIONS; MOLECULAR SPECTROSCOPIC DATABASE; RADIATIVE-TRANSFER; MU-M; STRATOSPHERIC TEMPERATURES; ATMOSPHERIC CONDITIONS; SPECTRAL RADIANCES; COEFFICIENT DATA; LINE PARAMETERS; SEA-SURFACE AB The Tropospheric Emission Spectrometer (TES) is a high-resolution spaceborne sensor that is capable of observing tropospheric species. In order to exploit fully TES's potential for tropospheric constituent retrievals, an accurate and fast operational forward model was developed for TES. The forward model is an important component of the TES retrieval model, the Earth Limb and Nadir Operational Retrieval (ELANOR), as it governs the accuracy and speed of the calculations for the retrievals. In order to achieve the necessary accuracy and computational efficiency, TES adopted the strategy of utilizing precalculated absorption coefficients generated by the line-by-line calculations provided by line-by-line radiation transfer modeling. The decision to perform the radiative transfer with the highest monochromatic accuracy attainable, rather than with an accelerated scheme that has the potential to add algorithmic forward model error, has proven to be very successful for TES retrievals. A detailed description of the TES forward model and Jacobians is described. A preliminary TES observation is provided as an example to demonstrate that the TES forward model calculations represent TES observations. Also presented is a validation example, which is part of the extensive forward model validation effort. C1 Atmospher & Environm Res Inc, Lexington, MA 02421 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Univ Denver, Denver, CO 80208 USA. Raytheon Tech Serv Co LLC, Pasadena, CA 91101 USA. RP Clough, SA (reprint author), Atmospher & Environm Res Inc, Lexington, MA 02421 USA. EM sclough@aer.com; mshephar@aer.com NR 78 TC 52 Z9 53 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1308 EP 1323 DI 10.1109/TGRS.2005.860986 PG 16 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100024 ER PT J AU Kulawik, SS Worden, H Osterman, G Luo, M Beer, R Kinnison, DE Bowman, KW Worden, J Eldering, A Lampel, M Steck, T Rodgers, CD AF Kulawik, SS Worden, H Osterman, G Luo, M Beer, R Kinnison, DE Bowman, KW Worden, J Eldering, A Lampel, M Steck, T Rodgers, CD TI TES atmospheric profile retrieval characterization: An orbit of simulated observations SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE EOS-Aura; error analysis; infrared spectroscopy; nonlinear estimation; simulation; Tropospheric Emission Spectrometer (TES) ID OZONESONDE DATA; COOLING RATES; RECOMMENDATIONS; FLUXES; MODELS AB We test the accuracy of our error analysis and retrieval performance by examining retrievals over an orbits' worth of simulated data covering a variety of atmospheric conditions. The use of simulated data allows validation of the error analysis and retrieval algorithm by comparisons to the true values. To demonstrate typical results, two example retrievals are shown, along with associated diagnostic information. Curtain plots display comparisons between the retrieved results, the true values, and the initial guesses. The results show that the Tropospheric Emission Spectrometer (TES) retrieval algorithm is robust under a variety of atmospheric conditions, that TES can improve on the a priori for nadir species Tatim H2O, O-3, and CO, and that the predicted errors match well with the actual retrieved errors. The target scenes (nadir, ocean, cloud-free) simulate conditions that are most easily validated with real data, and comparisons of on orbit results can be made with this baseline. C1 Jet Prop Lab, Pasadena, CA 91109 USA. Natl Ctr Atmospher Res, Boulder, CO 80301 USA. Raytheon ITSS, Pasadena, CA 91101 USA. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. Univ Oxford, Dept Phys, Oxford OX1 3PU, England. RP Kulawik, SS (reprint author), Jet Prop Lab, Pasadena, CA 91109 USA. EM Susan.Sund.Kulawik@jpl.nasa.gov NR 23 TC 25 Z9 25 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1324 EP 1333 DI 10.1109/TGRS.2006.871207 PG 10 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100025 ER PT J AU Kulawik, SS Osterman, G Jones, DBA Bowman, KW AF Kulawik, SS Osterman, G Jones, DBA Bowman, KW TI Calculation of altitude-dependent Tikhonov constraints for TES nadir retrievals SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE EOS-Aura; error analysis; infrared remote sensing; Fourier transform spectrometry (FTS); nonlinear estimation; Tropospheric Emission Spectrometer (TES) ID MODEL DESCRIPTION; OZONESONDE DATA; REGULARIZATION; RECOMMENDATIONS AB A key component in the regularization of vertical atmospheric trace gas retrievals is the construction of constraint matrices. We introduce a novel method for developing a constraint matrix based on altitude-varying combinations of zeroth-, first-, and second-order derivatives of the trace gas profile. This constraint matrix can be optimized to minimize the diagonal a posteriori error covariance and can also consider other factors such as degrees of freedom. This approach is applied to the calculation of constraint matrices for Tropospheric Emission Spectrometer nadir retrievals of atmospheric temperature, H2O, O-3, CO, and CH4. The retrieval error achieved with these constraints is comparable to the error achieved with the classical Bayesian constraint. Furthermore, these constraints are shown to be robust under uncertainty in the climatological conditions. C1 Jet Prop Lab, Pasadena, CA 91109 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Kulawik, SS (reprint author), Jet Prop Lab, Pasadena, CA 91109 USA. EM Susan.Sund.Kulawik@jpl.nasa.gov RI Jones, Dylan/O-2475-2014 OI Jones, Dylan/0000-0002-1935-3725 NR 18 TC 34 Z9 34 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1334 EP 1342 DI 10.1109/TGRS.2006.871206 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100026 ER PT J AU Paradise, S Akopyan, S De Baca, RC Croft, K Fry, K Gluck, S Ho, D Koffend, B Lampel, M McDuffie, J Monarrez, R Nair, H Poosti, S Shepard, D Strickland, I Tremblay, D Yun, H Zong, J AF Paradise, S Akopyan, S De Baca, RC Croft, K Fry, K Gluck, S Ho, D Koffend, B Lampel, M McDuffie, J Monarrez, R Nair, H Poosti, S Shepard, D Strickland, I Tremblay, D Yun, H Zong, J TI TES ground data system software SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE data processing; EOS-Aura; ground system; Tropospheric Emission Spectrometer (TES) AB Software development in support of the tropospheric emission spectrometer instrument ground data system has undergone many challenges due to the uniqueness of the instrument, complexity of the science, data volume, and performance requirements. In this paper, we describe the software, its development, and the way in which many of these challenges were met. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Raytheon ITSS, Pasadena, CA 91101 USA. RP Paradise, S (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Susan.Paradise@jpl.nasa.gov NR 18 TC 2 Z9 2 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1343 EP 1351 DI 10.1109/TGRS.2006.871205 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100027 ER PT J AU Chu, E Tremblay, D Croft, K Griffin, A AF Chu, E Tremblay, D Croft, K Griffin, A TI TES Science Investigator-led Processing System SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE atmospheric measurements; calibration; computer; architecture; computer facilities; data processing; Fourier spectroscopy; Fourier transform; multiprocessing; optical interferometry; parallel processing; processor scheduling; spectroscopy; terrestrial atmosphere AB The Tropospheric Emission Spectrometer (TES) is one of four instruments onboard the Earth Observing System Aura satellite. The TES Science Investigator-led Processing System (SIPS) Facility performs production processing of all TES science data. When the TES project was proposed in 1988, its science algorithms were still evolving, but it was already understood to be at least two orders of magnitude more complex than its NASA predecessor, the Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument. In addition, the expected data volume of the TES instrument would be more than 1000 times greater than that of ATMOS. Development of the TES S I PS faced a number of technical challenges. It also would have been impractical and prohibitively costly to develop the TES SIPS facility without carefully deploying the computing technologies that have recently become available. This paper describes how the challenges were met in the development of the facility by making use of evolving hardware technology and software refinement. The process revealed that the architecture of the hardware implemented was highly dependent upon the processing algorithm, and a stable algorithm was needed early in the hardware development process for performance analysis and benchmarking. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Raytheon ITSS, Pasadena, CA 91101 USA. RP Chu, E (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM chu@tes-mail.jpl.nasa.gov; dtremblay@tes-mail.jpl.nasa.gov; kcroft@tes-mail.jpl.nasa.gov; agriffin@sdsio.jpl.nasa.gov NR 10 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1352 EP 1358 DI 10.1109/TGRS.2005.863713 PG 7 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100028 ER PT J AU Lary, DJ Lait, L AF Lary, DJ Lait, L TI Using probability distribution functions for satellite validation SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Review DE chemical data assimilation; probability distribution functions (PDFs); representativeness uncertainty; spatial variability ID ATMOSPHERE RESEARCH SATELLITE; MICROWAVE LIMB SOUNDER; CRYOGENIC INFRARED SPECTROMETERS; CHEMISTRY EXPERIMENT ACE; CONCENTRATION FLUCTUATION MEASUREMENTS; HALOGEN OCCULTATION EXPERIMENT; SOLAR BACKSCATTER ULTRAVIOLET; ADVECTION-DIFFUSION PROBLEM; LAGRANGIAN-MEAN DESCRIPTION; OZONE DATA SET AB Probability distribution functions (PDFs) can be used to assist in the validation of trace gas retrievals made by satellites. A major advantage of this approach is that large statistical samples are used that do not require correlative measurements to be co-located in space and time. Examples are shown from the launch of UARS through to the present. This approach is also useful to evaluate the consistency among Aura instruments as well as their agreement with other datasets. A key feature of this work is putting the observations of Aura in their long-term historical context via statistical comparisons with previous datasets collected over more than a decade. To validate the Aura data, we use data from a variety of platforms including solar occultation (Canadian ACE) and limb sounder satellite instruments, ozonesondes (WOUDC), lidar (NDSC), and aircraft instruments (AVE, PAVE, and MOZAIC). The width of the trace gas PDFs can be used to accurately estimate the atmospheric spatial variability (or representativeness uncertainty) of trace gases as a function of time and location. This statistical analysis is also being used as preparation for full Kalman filter chemical assimilations. The analysis is presented online at http://ww-tv.PDFCentral.info. C1 Univ Maryland Baltimore Cty, NASA, Goddard Space Flight Ctr, GEST,Global Modeling & Assimilat Off, Baltimore, MD 20771 USA. RP Lary, DJ (reprint author), Univ Maryland Baltimore Cty, NASA, Goddard Space Flight Ctr, GEST,Global Modeling & Assimilat Off, Baltimore, MD 20771 USA. EM David.Lary@umbc.edu RI Lary, David/A-6163-2010; Zhang, YIng/F-5751-2011 NR 104 TC 10 Z9 10 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1359 EP 1366 DI 10.1109/TGRS.2005.860662 PG 8 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100029 ER PT J AU Read, WG Shippony, Z Schwartz, MJ Livesey, NJ Van Snyder, W AF Read, WG Shippony, Z Schwartz, MJ Livesey, NJ Van Snyder, W TI The clear-sky unpolarized forward model for the EOS Aura Microwave Limb Sounder (MLS) SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE Aura; Earth Observing System (EOS); Microwave Limb Sounder (MLS); radiative transfer; spectroscopy ID SUBMILLIMETER; RETRIEVAL; UARS AB This paper describes the Earth Observing System (EOS) Aura Microwave Limb Sounder (MLS) forward model for a clear-sky atmosphere emitting unpolarized radiation. This model is used for the majority of the EOS MLS radiance calculations. The orbital and viewing geometry of MLS on Aura is such that a two-dimensional (vertical and line-of-sight, horizontal) forward model provides the most accurate basis for the inversion performed in retrievals. The model consists of atmospheric radiative transfer convolved with the instrumental field of view and the spectral response. An additional model relating the pointing heights supplied by the Aura satellite operations and MLS scan pointing encoders to the limb tangent pressure and atmospheric temperature is described. The analytic computation of Jacobians needed for retrievals is given. C1 Jet Prop Lab, Pasadena, CA 91109 USA. RP Read, WG (reprint author), Jet Prop Lab, Pasadena, CA 91109 USA. EM bill@mls.jpl.nasa.gov RI Schwartz, Michael/F-5172-2016 OI Schwartz, Michael/0000-0001-6169-5094 NR 31 TC 34 Z9 35 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2006 VL 44 IS 5 BP 1367 EP 1379 DI 10.1109/TGRS.2006.873233 PG 13 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 037SK UT WOS:000237167100030 ER PT J AU Gandhi, T Yang, MT Kasturi, R Camps, OI Coraor, LD McCandless, J AF Gandhi, T Yang, MT Kasturi, R Camps, OI Coraor, LD McCandless, J TI Performance characterization of the dynamic programming obstacle detection algorithm SO IEEE TRANSACTIONS ON IMAGE PROCESSING LA English DT Article DE autonomous navigation; dynamic programming; obstacle detection; performance characterization; target detection AB A computer vision-based system using images from an airborne aircraft can increase flight safety by aiding the pilot to detect obstacles in the flight path so as to avoid mid-air collisions. Such a system fits naturally with the development of an external vision system proposed by NASA for use in high-speed civil transport aircraft with limited cockpit visibility. The detection techniques should provide high detection probability for obstacles that can vary from subpixels to a few pixels in size, while maintaining a low false alarm probability in the presence of noise and severe background clutter. Furthermore, the detection algorithms must be able to report such obstacles in a timely fashion, imposing severe constraints on their execution time. For this purpose, we have implemented a number of algorithms to detect airborne obstacles using image sequences obtained from a camera mounted on an aircraft. This paper describes the methodology used for characterizing the performance of the dynamic programming obstacle detection algorithm and its special cases. The experimental results were obtained using several types of image sequences, with simulated and real backgrounds. The approximate performance of the algorithm is also theoretically derived using principles of statistical analysis in terms of the signal-to-noise ration (SNR) required for the probabilities of false alarms and misdetections to be lower than prespecified values. The theoretical and experimental performance are compared in terms of the required SNR. C1 Univ Calif San Diego, Comp Vis & Robot Res Lab, La Jolla, CA 92093 USA. Natl Dong Hwa Univ, Dept Comp Sci & Informat Engn, Hualien, Taiwan. Univ S Florida, Dept Comp Sci & Engn, Tampa, FL 33620 USA. Penn State Univ, Dept Elect Engn, University Pk, PA 16802 USA. Penn State Univ, Dept Comp Sci & Engn, University Pk, PA 16802 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Gandhi, T (reprint author), Univ Calif San Diego, Comp Vis & Robot Res Lab, La Jolla, CA 92093 USA. EM tarakgandhi@hotmail.com; mtyang@mail.ndhu.edu.tw; rlk@cse.usf.edu; camps@psu.edu; coraor@cse.psu.edu; jeffrey.mccandless@nasa.gov NR 11 TC 8 Z9 9 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1057-7149 J9 IEEE T IMAGE PROCESS JI IEEE Trans. Image Process. PD MAY PY 2006 VL 15 IS 5 BP 1202 EP 1214 DI 10.1109/TIP.2005.863973 PG 13 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 032WN UT WOS:000236807100015 PM 16671301 ER PT J AU Stevens, R Nguyen, C Meyyappan, M AF Stevens, R Nguyen, C Meyyappan, M TI Nanomanipulation and fabrication by ion beam molding SO IEEE TRANSACTIONS ON NANOTECHNOLOGY LA English DT Article DE carbon nanotube; ion beam molding; nanofabrication; nanomanipulation; nanomanufacturing ID ATOMIC-FORCE MICROSCOPY; NANOTUBE SCANNING PROBE; CARBON NANOTUBE; TIPS AB Nanoscale manipulation is a basic ability needed to realize many of the nanotechnology applications. We demonstrate an ion bean molding technique to shape the configuration of nanostructures. As an example, the native curvature of a carbon nanotube in an atomic force microscope tip and its undesirable angle with respect to the surface are removed by this technique to render the nanotube straight. The straightened nanotube is effectively used in a semiconductor profilometry application. The ion beam molding technique is also shown to be effective in creating a desirable net shape of nanotubes. As mechanical deformation determines electrical and other properties of nanotubes, such manipulation may be of use in nanodevice fabrication. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Stevens, R (reprint author), Modus Technol, San Francisco, CA 94107 USA. EM ramsey@modusnano.com; mmeyyappan@mail.arc.nasa.gov NR 14 TC 7 Z9 7 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1536-125X J9 IEEE T NANOTECHNOL JI IEEE Trans. Nanotechnol. PD MAY PY 2006 VL 5 IS 3 BP 255 EP 257 DI 10.1109/TNANO.2006.874056 PG 3 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Science & Technology - Other Topics; Materials Science; Physics GA 046PB UT WOS:000237822400020 ER PT J AU Polak, S Barniv, Y Baram, Y AF Polak, Simon Barniv, Yair Baram, Yoram TI Head motion anticipation for virtual-environment applications using kinematics and EMG energy SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART A-SYSTEMS AND HUMANS LA English DT Article DE electromyogram; head-mounted display; neural networks; pattern recognition; virtual environment ID MUSCLE; MODEL AB Real-time human-computer interaction plays an important role in virtual-environment (VE) applications. Such interaction can be improved by detecting and reacting to the user's head motion. Today's VE systems use head-mounted inertial sensors to update and spatially stabilize the image displayed to a user through a head-mounted display. Since motion can only be detected after it has already occurred, latencies in the stabilization scheme can only be reduced but never eliminated. Such latencies slow down manual control, cause inaccuracies in matching real and virtual objects through a half-transparent display, and reduce the sense of presence. This paper presents novel methods for reducing VE latencies by anticipating future head motion based on electromyographic (EMG) signals originating from the major neck muscles and head kinematics; it also reports results for anticipation of 17.5 and 35 ms. Features extracted from the EMG signals are used to train a neural network in mapping EMG data, given present head kinematics, into future head motion. The trained network is then used in real time for head-motion anticipation, which gives the VE system the time advantage necessary to compensate for the inherent latencies. The main contribution of this work is the use of EMG energy and bounded head acceleration as the key input/output information. which results in improved performance compared to the previous work. C1 Technion Israel Inst Technol, Dept Comp Sci, IL-32000 Haifa, Israel. NASA, Ames Res Ctr, Human Informat Proc Res Branch, Moffett Field, CA 94035 USA. RP Polak, S (reprint author), Technion Israel Inst Technol, Dept Comp Sci, IL-32000 Haifa, Israel. EM cspolak@tx.technion.ac.il; ybarniv@mail.arc.nasa.gov; baram@cs.technion.ac.il NR 26 TC 7 Z9 7 U1 0 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1083-4427 J9 IEEE T SYST MAN CY A JI IEEE Trans. Syst. Man Cybern. Paart A-Syst. Hum. PD MAY PY 2006 VL 36 IS 3 BP 569 EP 576 DI 10.1109/TSMCA.2005.855781 PG 8 WC Computer Science, Cybernetics; Computer Science, Theory & Methods SC Computer Science GA 041LL UT WOS:000237457600017 ER PT J AU Truszkowski, WF Hinchey, MG Rash, JL Rouff, CA AF Truszkowski, Walter F. Hinchey, Michael G. Rash, James L. Rouff, Christopher A. TI Autonomous and autonomic systems: A paradigm for future space exploration missions SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART C-APPLICATIONS AND REVIEWS LA English DT Article; Proceedings Paper CT 11th IEEE International Conference and Workshop on Engineering of Computer-Based Systems (ECBS 2004) CY MAY 24-27, 2004 CL Brno, CZECH REPUBLIC SP IEEE, Brno Univ Technol DE autonomic systems; autonomous systems; intelligent systems; multiagent technology; spacecraft AB More and more, the National Aeronautics and Space Administration (NASA) will rely on concepts from autonomous systems not only in mission control centers on the ground, but also on spacecraft and on rovers and other space assets on extraterrestrial bodies. Autonomy facilitates not only reduced operations costs, but also adaptable goal-driven functionality of mission systems. Space missions lacking autonomy will be unable to achieve the full range of advanced mission objectives, given that human control under dynamic environmental conditions will not be feasible due, in part, to the unavoidably high signal propagation latency and constrained data rates of mission communications links. While autonomy supports cost-effective accomplishment of mission goals, autonomicity supports survivability of remote mission assets, especially when tending by humans is not feasible. In principle, the properties of antonomic systems may enable space missions of a higher order than any previously flown. Analysis of two NASA agent-based systems previously prototyped, and of a proposed future mission involving numerous cooperating spacecraft, illustrates how autonomous and autonomic system concepts may be brought to bear on future space missions. C1 NASA, Adv Architectures & Automat Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Software Engn Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, Adv Concepts Business Unit, Mclean, VA 22102 USA. RP Truszkowski, WF (reprint author), NASA, Adv Architectures & Automat Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM Walter.F.Truszkowski@nasa.gov; Michael.G.Hinchey@nasa.gov; James.L.Rash@nasa.gov; rouffc@saic.com NR 22 TC 29 Z9 29 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1094-6977 EI 1558-2442 J9 IEEE T SYST MAN CY C JI IEEE Trans. Syst. Man Cybern. Part C-Appl. Rev. PD MAY PY 2006 VL 36 IS 3 BP 279 EP 291 DI 10.1109/TSMCC.2006.871600 PG 13 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Interdisciplinary Applications SC Computer Science GA 043DS UT WOS:000237580400002 ER PT J AU Kaber, DB Perry, CM Segall, N McClernon, CK Prinzel, LJ AF Kaber, David B. Perry, Carlene M. Segall, Noa McClernon, Christopher K. Prinzel, Lawrence J., III TI Situation awareness implications of adaptive automation for information processing in an air traffic control-related task SO INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS LA English DT Article DE adaptive automation; situation awareness; air traffic control; workload ID DYNAMIC-SYSTEMS; PERFORMANCE; DESIGN; MODEL AB The objective of this research was to assess the effectiveness of adaptive automation (AA) for supporting information processing (IP) in a complex, dynamic control task by defining a measure of situation awareness (SA) sensitive to differences in the forms of automation. The task was an air traffic control (ATC)-related simulation and was developed to present four different modes of automation of IP functions, including information acquisition, information analysis, decision making and action implementation automation, as well as a completely manual control mode. A total of 16 participants were recruited for a pilot study and primary experiment. The pilot assessed the sensitivity and reliability of the Situation Awareness Global Assessment Technique (SAGAT) for describing AA support of the IP functions. Half of the participants were used in the primary experiment, which refined the SA measure and described the implications of AA for IP on SA using the ATC-like simulation. Participants were exposed to all forms of automation and manual control. AA conditions matched operator workload states to dynamic control allocations in the primary task. The pilot did not reveal significant differences in SA among the various AA conditions. In the primary experiment, participant recall of aircraft was cued and relevance weights were assigned to aircraft at the time of simulation freezes. The modified measure of SA revealed operator perception and Total SA to improve when automation was applied to the information acquisition function. In both experiments, performance in the ATC-related task simulation was significantly superior when automation was applied to information acquisition and action implementation (sensory and motor processing), as compared to automation of cognitive functions, specifically information analysis. The primary experiment revealed information analysis and decision-making automation to cause higher workload, attributable to visual demands of displays. Industry relevance The results of this research may serve as a general guide for the design of adaptive automation functionality in the aviation industry, particularly for information processing support in air traffic control tasks. (c) 2006 Elsevier B.V. All rights reserved. C1 Univ Rostock, Coll Informat & Elect Engn, Inst Automat, Rostock, Germany. N Carolina State Univ, Edward P Fitts Dept Ind Engn, Raleigh, NC 27695 USA. NASA, Langley Res Ctr, Hampton, VA USA. RP Kaber, DB (reprint author), Univ Rostock, Coll Informat & Elect Engn, Inst Automat, Rostock, Germany. EM dbkaber@ncsu.edu NR 41 TC 50 Z9 54 U1 5 U2 31 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-8141 J9 INT J IND ERGONOM JI Int. J. Ind. Ergon. PD MAY PY 2006 VL 36 IS 5 BP 447 EP 462 DI 10.1016/j.ergon.2006.01.008 PG 16 WC Engineering, Industrial; Ergonomics SC Engineering GA 043YO UT WOS:000237639200006 ER PT J AU Siegel, PH Dengler, RJ AF Siegel, Peter H. Dengler, Robert J. TI Terahertz heterodyne imaging Part II: Instruments SO INTERNATIONAL JOURNAL OF INFRARED AND MILLIMETER WAVES LA English DT Article ID WAVE; HORN; AMPLIFIERS; ARRAYS AB This paper is Part II of a series of articles on Terahertz heterodyne imaging. In Pan I introductory information and techniques were presented. In this paper the authors describe four different types of heterodyne imaging instruments that have been established at their facilities. In Part III (to appear in a future issue of this journal) selected applications of these instruments are discussed. C1 CALTECH, Beckman Inst, Div Biol, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Submilliter Wave Adv Technol, Pasadena, CA 91109 USA. RP Siegel, PH (reprint author), CALTECH, Beckman Inst, Div Biol, 1200 E Calif Blvd, Pasadena, CA 91125 USA. EM phs@caltech.edu NR 51 TC 28 Z9 29 U1 0 U2 7 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0195-9271 J9 INT J INFRARED MILLI JI Int. J. Infrared Millimeter Waves PD MAY PY 2006 VL 27 IS 5 BP 631 EP 655 DI 10.1007/s10762-006-9109-4 PG 25 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 075QJ UT WOS:000239900000001 ER PT J AU Stanford, MK Ward, LD DellaCorte, C AF Stanford, MK Ward, LD DellaCorte, C TI Elevated-temperature stability of a PM composite solid lubricant SO INTERNATIONAL JOURNAL OF POWDER METALLURGY LA English DT Article ID KINETICS AB The elevated-temperature stability of PM300, a powder metallurgy (PM) composite solid lubricant composed of nickel-chromium, chromia, silver, and an alkaline earth fluoride, has been examined. Specimens were exposed at 500 degrees C and 650 degrees C in air for time intervals up to 5,000 h and then characterized in terms of changes in mass, size, hardness, and microstructure. After exposure, the microstructure exhibited precipitates within the nickel-chromium constituent, and a corresponding increase in mass, size, and hardness. The increase in mass and size followed a logarithmic curve; this behavior establishes guidelines for heat-treatment parameters. C1 NASA, John H Glenn Res Ctr Lewis Field, Oil Free Turbomachinery Tech Lead, Cleveland, OH 44135 USA. Spelman Coll, Atlanta, GA 30314 USA. RP Stanford, MK (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Oil Free Turbomachinery Tech Lead, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM malcolm.k.stanford@nasa.gov NR 26 TC 3 Z9 3 U1 0 U2 3 PU AMER POWDER METALLURGY INST PI PRINCETON PA 105 COLLEGE ROAD EAST, PRINCETON, NJ 08540 USA SN 0888-7462 J9 INT J POWDER METALL JI Int. J. Powder Metall. PD MAY-JUN PY 2006 VL 42 IS 3 BP 37 EP 47 PG 11 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 050GR UT WOS:000238076000008 ER PT J AU Seiz, G Davies, R Grun, A AF Seiz, G Davies, R Grun, A TI Stereo cloud-top height retrieval with ASTER and MISR SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID SPACEBORNE THERMAL EMISSION; REFLECTION RADIOMETER ASTER AB The combined multi-view photogrammetric retrieval of cloud-top height (CTH) from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Multi-angle Imaging SpectroRadiometer (MISR) is discussed. Although ASTER was designed mainly for land applications, the synergistic use of MISR and ASTER is shown to be valuable for 3D cloud analysis. A new cloud-adapted matching algorithm based on least-squares matching (LSM) was used for the photogrammetric processing of both MISR and ASTER. The methods were applied to an ASTER scene over Zurich-Kloten, Switzerland, in April 2002, which was acquired on-demand. This case study, with coincident ASTER, MISR and Meteosat-6 10-minute Rapid Scans, is treated in detail. As a matching validation option it is shown that, by chance, the cloud motion error for the MISR An-Aa and ASTER stereo CTHs is approximately the same, independent of the actual cloud height and cloud motion. It was therefore possible to evaluate the accuracy of the MISR An-Aa matching versus the ASTER matching, independent of artefacts due to the subsequent wind correction. The results were also compared to the operational MISR L2TC stereo CTH results. The results obtained by each of these methods yield consistent values for CTH (uncorrected for wind motion). C1 ETH Honggerberg, Swiss Fed Inst Technol, Inst Geodesy & Photogrammetry, CH-8093 Zurich, Switzerland. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Seiz, G (reprint author), ETH Honggerberg, Swiss Fed Inst Technol, Inst Geodesy & Photogrammetry, CH-8093 Zurich, Switzerland. EM gabriela.seiz@esa.int RI Davies, Roger/D-4296-2009 OI Davies, Roger/0000-0002-2991-0409 NR 27 TC 10 Z9 10 U1 0 U2 5 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAY PY 2006 VL 27 IS 9-10 BP 1839 EP 1853 DI 10.1080/01431160500380703 PG 15 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 058GE UT WOS:000238652700008 ER PT J AU Karnieli, A Bayasgalan, M Bayarjargal, Y Agam, N Khudulmur, S Tucker, CJ AF Karnieli, A Bayasgalan, M Bayarjargal, Y Agam, N Khudulmur, S Tucker, CJ TI Comments on the use of the vegetation health index over Mongolia SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID HIGH-RESOLUTION RADIOMETER; AVHRR-BASED VEGETATION; MONITORING VEGETATION; DROUGHT DETECTION; SENEGALESE SAHEL; TEMPERATURE; SPACE; NDVI; PHENOLOGY; RESPONSES AB The Vegetation Health index (VHI) is based on a combination of products extracted from vegetation signals, namely the Normalized Difference Vegetation Index (NDVI) and from the brightness temperatures, both derived from the NOAA Advanced Very High Resolution Radiometer (AVHRR) sensor. VH users rely on a strong inverse correlation between NDVI and land surface temperature, since increasing land temperatures are assumed to act negatively on vegetation vigour and consequently to cause stress. This Letter explores this hypothesis with data from Mongolia incorporating information from six different ecosystems. It was found that the northern ecosystems are characterized by positive correlations, implying that rising temperature favourably influences vegetation activity. It is concluded that the VHI should be used with caution, especially in high latitude regions. C1 Ben Gurion Univ Negev, Remote Sensing Lab, Jacob Blaustein Inst Desert Res, IL-84990 Sede Boqer, Israel. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Karnieli, A (reprint author), Ben Gurion Univ Negev, Remote Sensing Lab, Jacob Blaustein Inst Desert Res, Sede Boker Campus, IL-84990 Sede Boqer, Israel. EM karnieli@bgu.ac.il OI Agam, Nurit/0000-0002-8921-6179 NR 30 TC 43 Z9 44 U1 2 U2 10 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAY PY 2006 VL 27 IS 9-10 BP 2017 EP 2024 DI 10.1080/01431160500121727 PG 8 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 058GE UT WOS:000238652700021 ER PT J AU Apetre, NA Sankar, BV Ambur, DR AF Apetre, NA Sankar, BV Ambur, DR TI Low-velocity impact response of sandwich beams with functionally graded core SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE contact problem; functionally graded cores; functionally graded materials; impact damage; low-velocity impact; sandwich panels ID RECTANGULAR-PLATES; THERMAL-GRADIENTS; COMPOSITES; DEFORMATIONS; FABRICATION; STRESSES; FORCE AB The problem of low-speed impact of a one-dimensional sandwich panel by a rigid cylindrical projectile is considered. The core of the sandwich panel is functionally graded such that the density, and hence its stiffness, vary through the thickness. The problem is a combination of static contact problem and dynamic response of the sandwich panel obtained via a simple nonlinear spring-mass model (quasi-static approximation). The variation of core Young's modulus is represented by a polynomial in the thickness coordinate, but the Poisson's ratio is kept constant. The two-dimensional elasticity equations for the plane sandwich structure are solved using a combination of Fourier series and Galerkin method. The contact problem is solved using the assumed contact stress distribution method. For the impact problem we used a simple dynamic model based on quasi-static behavior of the panel-the sandwich beam was modeled as a combination of two springs, a linear spring to account for the global deflection and a nonlinear spring to represent the local indentation effects. Results indicate that the contact stiffness of the beam with graded core increases causing the contact stresses and other stress components in the vicinity of contact to increase. However, the values of maximum strains corresponding to the maximum impact load are reduced considerably due to grading of the core properties. For a better comparison, the thickness of the functionally graded cores was chosen such that the flexural stiffness was equal to that of a beam with homogeneous core. The results indicate that functionally graded cores can be used effectively to mitigate or completely prevent impact damage in sandwich composites. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Florida, Dept Mech & Aerosp Engn, Gainesville, FL 32611 USA. NASA Glenn Res Ctr, Cleveland, OH 44135 USA. RP Sankar, BV (reprint author), Univ Florida, Dept Mech & Aerosp Engn, Gainesville, FL 32611 USA. EM sankar@ufl.edu OI Sankar, Bhavani/0000-0002-4556-1982 NR 38 TC 62 Z9 66 U1 3 U2 30 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD MAY PY 2006 VL 43 IS 9 BP 2479 EP 2496 DI 10.1016/j.ijsolstr.2005.06.003 PG 18 WC Mechanics SC Mechanics GA 030HT UT WOS:000236626100002 ER PT J AU Zhu, LF Chattopadhyay, A Goldberg, RK AF Zhu, LF Chattopadhyay, A Goldberg, RK TI Nonlinear transient response of strain rate dependent composite laminated plates using multiscale simulation SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE transient response; composite laminates; multiscale simulation; micromechanics model ID HIGHER-ORDER THEORY; SANDWICH PLATES; REFINED THEORY; WAVES AB The effects of strain rate dependency and inelasticity on the transient responses of composite laminated plates are investigated. A micromechanics model which accounts for the transverse shear stress effect, the effect of strain rate dependency and the effect of inelasticity is used for analyzing the mechanical responses of the fiber and matrix constituents. The accuracy of the micromechanics model under transverse shear loading is verified by comparing the results with those obtained using a general purpose finite element code. A higher order laminated plate theory is extended to capture the inelastic deformations of the composite plate and is implemented using the finite element technique. A complete micro-macro numerical procedure is developed to model the strain rate dependent behavior of inelastic composite laminates by implementing the micromechanics model into the finite element model. Parametric studies of the transient responses of composite plates are conduced. The effects of geometry, ply stacking sequence, material models, boundary conditions and loadings are investigated. The results show that the strain rate dependency and inelasticity influence the transient responses of composite plates via two significantly different mechanisms. (c) 2005 Elsevier Ltd. All rights reserved. C1 Arizona State Univ, Dept Mech & Aerosp Engn, Tempe, AZ 85287 USA. Nalt Aeronaut & Space Adm, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Arizona State Univ, Dept Mech & Aerosp Engn, Tempe, AZ 85287 USA. EM linfa.zhu@asu.edu NR 42 TC 17 Z9 18 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 EI 1879-2146 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD MAY PY 2006 VL 43 IS 9 BP 2602 EP 2630 DI 10.1016/j.ijsolstr.2005.06.033 PG 29 WC Mechanics SC Mechanics GA 030HT UT WOS:000236626100007 ER PT J AU Owens, DB McConnell, JK Brandon, JM Hall, RM AF Owens, DB McConnell, JK Brandon, JM Hall, RM TI Transonic free-to-roll analysis of the F-35 (Joint Strike Fighter) aircraft SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA Atmospheric Flight Mechanics Conference CY AUG, 2004 CL Providence, RI SP Amer Inst Aeronaut & Astronaut ID ABRUPT-WING-STALL AB The free-to-roll technique is used as a tool for-predicting areas of uncommanded lateral motions. Recently, the NASA/Navy/Air Force Abrupt Wing Stall Program extended the use of this technique to the transonic speed regime. Using this technique, this paper evaluates various wing configurations on the Joint Strike Fighter (F-35) aircraft. The configurations investigated include leading- and trailing-edge flap deflections, leading-edge flap gap seals, and vortex generators. These tests were conducted in the NASA Langley 16-Foot Transonic Tunnel. The analysis used a modification of a figure of merit developed during the Abrupt Wing Stall Program to discern configuration effects. The results showed how the figure of merit can be used to schedule, wing flap deflections to avoid areas of uncommanded lateral motion. The analysis also used both static and dynamic wind-tunnel data to provide insight into the uncommanded lateral behavior. The dynamic data were extracted from the time history data using parameter identification techniques. In general, sealing the gap between the inboard and outboard leading-edge flaps on the Navy version of the F-35 eliminated uncommanded lateral activity or delayed the activity to a higher angle of attack. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Lockheed Martin Aeronaut Co, Ft Worth, TX 76101 USA. RP Owens, DB (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 28 TC 4 Z9 5 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2006 VL 43 IS 3 BP 608 EP 615 PG 8 WC Engineering, Aerospace SC Engineering GA 058NA UT WOS:000238670500005 ER PT J AU Li, W Krist, S Campbell, R AF Li, W Krist, S Campbell, R TI Transonic airfoil shape optimization in preliminary design environment SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA/ISSMO 10th Symposium on Multidisciplinary Analysis and Optimization CY AUG 30, 2001-SEP 01, 2004 CL Albany, NY SP Amer Inst Aeronaut & Astronaut, ISSMO AB A modified profile optimization method using a smoothest shape modification strategy (POSSEM) is developed for airfoil shape optimization in a preliminary design environment. POS EM is formulated to overcome two technical difficulties frequently encountered when conducting multipoint airfoil optimization within a high-resolution design space: the generation of undesirable optimal airfoil shapes and significant degradation in the off-design performance. To demonstrate the usefulness or POSSEM in a preliminary design environment, a design competition was conducted with the objective of improving a fairly well-designed baseline airfoil at four transonic flight conditions without incurring any off-design performance degradation. Independently, two designs were generated from the inverse design tool CDISC, while a third design was generated from POSSEM, using over 200 control points of a cubic B-spline curve representation of the airfoil as design variables for the shape optimization. Pros and cons of all of the airfoil designs are documented along with in-depth analyses of simulation results. The POSSEM design exhibits a fairly smooth curvature and no degradation in the off-design performance. Moreover, it has the lowest average drag at the design conditions among the three airfoil designs, as evaluated from each of three different flow solvers. C1 NASA, Langley Res Ctr, Aeronaut Syst Anal Branch, Syst Anal Concept Directorate, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Configurat Aerodynam Branch, Res & Technol Directorate, Hampton, VA 23681 USA. RP Li, W (reprint author), NASA, Langley Res Ctr, Aeronaut Syst Anal Branch, Syst Anal Concept Directorate, Hampton, VA 23681 USA. NR 16 TC 3 Z9 4 U1 1 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2006 VL 43 IS 3 BP 639 EP 651 DI 10.2514/1.13921 PG 13 WC Engineering, Aerospace SC Engineering GA 058NA UT WOS:000238670500008 ER PT J AU Rossow, VJ AF Rossow, VJ TI Origin of exponential solution for laminar decay of isolated vortex SO JOURNAL OF AIRCRAFT LA English DT Article AB The origin of the exact, closed-form, self similar exponential solution for the laminar decay of an isolated two-dimensional vortex in a viscous incompressible fluid is studied to find a proper name for the function. Two major contributions to the solution are the similarity parameter derived by Boltzmann and the derivation of the form of the solution by Carslaw for the diffusion of heat from a line source, that is, a spark or lightning stroke. Lamb adapted the heat transfer solution derived by Carslaw to the time-dependent diffusion of vorticity from a potential line vortex, and, after publication of his book, has provided a short, complete, and readily available derivation. Oseen's derivation followed about four years later and is not as complete. Various titles for the solution are believed to be appropriate, including a generic name such as exponential vortex solution, or the name of Lamb. The name of Lamb is probably the most appropriate because he was the first in existing literature to put the entire derivation together and because the presentation is compact, complex, and readily available. C1 NASA, Ames Res Ctr, Aviat Syst Div, Moffett Field, CA 94035 USA. RP Rossow, VJ (reprint author), NASA, Ames Res Ctr, Aviat Syst Div, Mail Stop N210-10, Moffett Field, CA 94035 USA. NR 11 TC 4 Z9 5 U1 1 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2006 VL 43 IS 3 BP 709 EP 712 DI 10.2514/1.16970 PG 4 WC Engineering, Aerospace SC Engineering GA 058NA UT WOS:000238670500015 ER PT J AU Potsdam, M Yeo, H Johnson, W AF Potsdam, M Yeo, H Johnson, W TI Rotor airloads prediction using loose aerodynamic/structural coupling SO JOURNAL OF AIRCRAFT LA English DT Article ID DYNAMICS; GRIDS AB A computational fluid dynamics (CFD) code and rotorcraft computational structural dynamics (CSD) code are coupled to calculate helicopter rotor airloads across a range of flight conditions. An iterative loose (weak) coupling methodology is used to couple the CFD and CSD codes on a per revolution, periodic basis. The CFD code uses a high fidelity, Navier-Stokes, overset grid methodology with first principles-based wake capturing. Modifications are made to the CFD code for the aeroelastic analysis. For a UH-60A Blackhawk helicopter, three challenging level flight conditions are computed: 1) high speed, mu = 0.37, with advancing blade negative lift, 2) low speed, mu = 0.15, with blade-vortex interaction, and 3) high thrust with dynamic stall, mu = 0.24. Results are compared with UH-60A Airloads program flight test data. For all cases the loose coupling methodology is shown to be stable, convergent, and robust with full coupling of normal force, pitching moment, and chord force. In comparison with flight test data, normal force and pitching moment phase and magnitude are in good agreement. The shapes of the airloads curves are well captured. Overall, the results are a noteworthy improvement over lifting line aerodynamics used in rotorcraft comprehensive codes. C1 NASA, Ames Res Ctr, USA, Res Dev & Engn Command, Moffett Field, CA 94035 USA. RP Potsdam, M (reprint author), NASA, Ames Res Ctr, USA, Res Dev & Engn Command, MS 215-1, Moffett Field, CA 94035 USA. EM mpotsdam@mail.arc.nasa.gov NR 32 TC 48 Z9 54 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2006 VL 43 IS 3 BP 732 EP 742 DI 10.2514/1.14006 PG 11 WC Engineering, Aerospace SC Engineering GA 058NA UT WOS:000238670500018 ER PT J AU Chabalko, CC Hajj, MR Silva, WA AF Chabalko, CC Hajj, MR Silva, WA TI Flutter of high-speed civil transport flexible semispan model: Time-frequency analysis SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 45th Structures, Structural Dynamics and Materials Conference CY APR 19-22, 2004 CL Palm Springs, CA SP Amer Inst Aeronaut & Astronaut, ASME, ASCE, AHS, ASC ID WAVELET TRANSFORM; IDENTIFICATION AB Time/frequency analysis of fluctuations measured by pressure taps and strain gauges in the experimental studies of the flexible semispan model of a high-speed civil transport wing configuration is performed. The interest is in determining the coupling between the aerodynamic loads and structural motions that led to the hard flutter conditions and loss of the model. The results show that, away from the hard flutter point, the aerodynamic loads at all pressure taps near the wing tip and the structural motions contained the same frequency components. On the other hand, in the flow conditions leading to the hard flatter, the frequency content of the pressure fluctuations near the leading and trailing edges varied significantly. This led to contribution to the structural motions over two frequency ranges. The ratio of these ranges was near 2:1. which suggests the possibility of nonlinear structural coupling. C1 Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. NASA, Langley Res Ctr, Aeroelast Branch, Hampton, VA 23681 USA. RP Chabalko, CC (reprint author), Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, 0219 Norris Hall, Blacksburg, VA 24061 USA. EM mhajj@vt.edu RI Hajj, Muhammad/A-1176-2010 NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2006 VL 43 IS 3 BP 743 EP 748 DI 10.2514/1.13661 PG 6 WC Engineering, Aerospace SC Engineering GA 058NA UT WOS:000238670500019 ER PT J AU Hussaini, MY Thangam, S Woodruff, SL Zhou, Y AF Hussaini, MY Thangam, S Woodruff, SL Zhou, Y TI Development of a continuous model for simulation of turbulent flows SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 4th ASME/JSME Joint Fluids Engineering Conference CY JUL 06-10, 2003 CL Honolulu, HI SP ASME, JSME ID RENORMALIZATION-GROUP THEORY; EDDY-VISCOSITY; KOLMOGOROV FLOW; REYNOLDS-STRESS; 3 DIMENSIONS AB The development of a continuous turbulence model that is suitable,for representing both the subgrid scale stresses in large eddy simulation and the Reynolds stresses in the Reynolds averaged Navier-Stokes formulation is described. A recursion approach is used to bridge the length scale disparity from the cutoff wave number to those in the energy-containing range. The proposed model is analyzed in conjunction with direct numerical simulations of Kolmogorov flows. C1 Stevens Inst Technol, Dept Mech Engn, Hoboken, NJ 07030 USA. Florida State Univ, Sch Computat Sci & Informat Technol, Tallahassee, FL 32306 USA. Florida State Univ, Ctr Adv Power Syst, Tallahassee, FL 32306 USA. NASA, ICASE, Langley Res Ctr, Hampton, VA 23681 USA. RP Thangam, S (reprint author), Stevens Inst Technol, Dept Mech Engn, Hoboken, NJ 07030 USA. NR 23 TC 5 Z9 5 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0021-8936 J9 J APPL MECH-T ASME JI J. Appl. Mech.-Trans. ASME PD MAY PY 2006 VL 73 IS 3 BP 441 EP 448 DI 10.1115/1.2173006 PG 8 WC Mechanics SC Mechanics GA 044ME UT WOS:000237675800013 ER PT J AU Olson, WS Kummerow, CD Yang, S Petty, GW Tao, WK Bell, TL Braun, SA Wang, Y Lang, SE Johnson, DE Chiu, C AF Olson, WS Kummerow, CD Yang, S Petty, GW Tao, WK Bell, TL Braun, SA Wang, Y Lang, SE Johnson, DE Chiu, C TI Precipitation and latent heating distributions from satellite passive microwave radiometry. Part I: Improved method and uncertainties SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article ID REMOTE-SENSING APPLICATIONS; MELTING-LAYER MODEL; OCEAN RAIN RATE; TOGA COARE; STOCHASTIC-MODEL; SAMPLING ERROR; MOISTURE OBSERVATIONS; GLOBAL PRECIPITATION; PHYSICAL RETRIEVALS; CONVECTIVE SYSTEMS AB A revised Bayesian algorithm for estimating surface rain rate, convective rain proportion, and latent heating profiles from satellite-borne passive microwave radiometer observations over ocean backgrounds is described. The algorithm searches a large database of cloud-radiative model simulations to find cloud profiles that are radiatively consistent with a given set of microwave radiance measurements. The properties of these radiatively consistent profiles are then composited to obtain best estimates of the observed properties. The revised algorithm is supported by an expanded and more physically consistent database of cloud-radiative model simulations. The algorithm also features a better quantification of the convective and nonconvective contributions to total rainfall, a new geographic database, and an improved representation of background radiances in rain-free regions. Bias and random error estimates are derived from applications of the algorithm to synthetic radiance data, based upon a subset of cloud-resolving model simulations, and from the Bayesian formulation itself. Synthetic rain-rate and latent heating estimates exhibit a trend of high ( low) bias for low ( high) retrieved values. The Bayesian estimates of random error are propagated to represent errors at coarser time and space resolutions, based upon applications of the algorithm to TRMM Microwave Imager (TMI) data. Errors in TMI instantaneous rain-rate estimates at 0.5 degrees-resolution range from approximately 50% at 1 mm h(-1) to 20% at 14 mm h(-1). Errors in collocated spaceborne radar rain-rate estimates are roughly 50%-80% of the TMI errors at this resolution. The estimated algorithm random error in TMI rain rates at monthly, 2.5 resolution is relatively small ( less than 6% at 5 mm day(-1)) in comparison with the random error resulting from infrequent satellite temporal sampling (8%-35% at the same rain rate). Percentage errors resulting from sampling decrease with increasing rain rate, and sampling errors in latent heating rates follow the same trend. Averaging over 3 months reduces sampling errors in rain rates to 6%-15% at 5 mm day(-1), with proportionate reductions in latent heating sampling errors. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. Univ Wisconsin, Dept Atmospher & Ocean Sci, Madison, WI USA. Sci Syst & Applicat Inc, Lanham, MD USA. Goddard Earth Sci & Technol Ctr, Greenbelt, MD USA. RP Olson, WS (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613-1, Greenbelt, MD 20771 USA. EM olson@agnes.gsfc.nasa.gov RI Petty, Grant/E-3118-2012; Bell, Thomas/G-5425-2012; Chiu, Christine/E-5649-2013 OI Chiu, Christine/0000-0002-8951-6913 NR 48 TC 94 Z9 95 U1 0 U2 9 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1558-8424 J9 J APPL METEOROL CLIM JI J. Appl. Meteorol. Climatol. PD MAY PY 2006 VL 45 IS 5 BP 702 EP 720 DI 10.1175/JAM2369.1 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 055GF UT WOS:000238437400004 ER PT J AU Yang, S Olson, WS Wang, JJ Bell, TL Smith, EA Kummerow, CD AF Yang, S Olson, WS Wang, JJ Bell, TL Smith, EA Kummerow, CD TI Precipitation and latent heating distributions from satellite passive microwave radiometry. part II: Evaluation of estimates using independent data SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article ID PROFILING ALGORITHM; TROPICAL RAINFALL; MOISTURE BUDGETS; SAMPLING ERRORS; SUMMER MONSOON; TOGA COARE; RADAR; TRMM; AREA; VALIDATION AB Rainfall rate estimates from spaceborne microwave radiometers are generally accepted as reliable by a majority of the atmospheric science community. One of the Tropical Rainfall Measuring Mission (TRMM) facility rain-rate algorithms is based upon passive microwave observations from the TRMM Microwave Imager (TMI). In Part I of this series, improvements of the TMI algorithm that are required to introduce latent heating as an additional algorithm product are described. Here, estimates of surface rain rate, convective proportion, and latent heating are evaluated using independent ground-based estimates and satellite products. Instantaneous, 0.5 degrees-resolution estimates of surface rain rate over ocean from the improved TMI algorithm are well correlated with independent radar estimates (r similar to 0.88 over the Tropics), but bias reduction is the most significant improvement over earlier algorithms. The bias reduction is attributed to the greater breadth of cloud-resolving model simulations that support the improved algorithm and the more consistent and specific convective/stratiform rain separation method utilized. The bias of monthly 2.5 degrees-resolution estimates is similarly reduced, with comparable correlations to radar estimates. Although the amount of independent latent heating data is limited, TMI-estimated latent heating profiles compare favorably with instantaneous estimates based upon dual-Doppler radar observations, and time series of surface rain-rate and heating profiles are generally consistent with those derived from rawinsonde analyses. Still, some biases in profile shape are evident, and these may be resolved with ( a) additional contextual information brought to the estimation problem and/or (b) physically consistent and representative databases supporting the algorithm. A model of the random error in instantaneous 0.5 degrees-resolution rain-rate estimates appears to be consistent with the levels of error determined from TMI comparisons with collocated radar. Error model modifications for nonraining situations will be required, however. Sampling error represents only a portion of the total error in monthly 2.5 degrees-resolution TMI estimates; the remaining error is attributed to random and systematic algorithm errors arising from the physical inconsistency and/or nonrepresentativeness of cloud-resolving-model-simulated profiles that support the algorithm. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Colorado State Univ, Ft Collins, CO 80523 USA. RP Yang, S (reprint author), NASA, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA. EM ysong@agnes.gsfc.nasa.gov RI Bell, Thomas/G-5425-2012 NR 33 TC 40 Z9 41 U1 0 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1558-8424 J9 J APPL METEOROL CLIM JI J. Appl. Meteorol. Climatol. PD MAY PY 2006 VL 45 IS 5 BP 721 EP 739 DI 10.1175/JAM2370.1 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 055GF UT WOS:000238437400005 ER PT J AU Fiorino, ST Smith, EA AF Fiorino, ST Smith, EA TI Critical assessment of microphysical assumptions within TRMM radiometer rain profile algorithm using satellite, aircraft, and surface datasets from KWAJEX SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article ID RETRIEVAL ALGORITHMS; PRECIPITATION RADAR; SIZE DISTRIBUTIONS; ATTENUATION; SCATTERING; EMISSION; CLOUDS AB The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager precipitation profile retrieval algorithm (2a12) assumes cloud model-derived vertically distributed microphysics as part of the radiative transfer-controlled inversion process to generate rain-rate estimates. Although this algorithm has been extensively evaluated, none of the evaluation approaches has explicitly examined the underlying microphysical assumptions through a direct intercomparison of the assumed cloud-model microphysics with in situ, three-dimensional microphysical observations. The main scientific objective of this study is to identify and overcome the foremost model-generated microphysical weaknesses in the TRMM 2a12 algorithm through analysis of ( a) in situ aircraft microphysical observations; (b) aircraft- and satellite-based passive microwave measurements; ( c) ground-, aircraft-, and satellite-based radar measurements; (d) synthesized satellite brightness temperatures and radar reflectivities; ( e) radiometer-only profile algorithm retrievals; and (f) radar-only profile or volume algorithm retrievals. Results indicate the assumed 2a12 microphysics differs most from aircraft- observed microphysics where either ground or aircraft radar-derived rain rates exhibit the greatest differences with 2a12-retrieved rain rates. An emission-scattering coordinate system highlights the 2a12 algorithm's tendency to match high-emission/high-scattering observed profiles to high-emission/low-scattering database profiles. This is due to a lack of mixed-phase-layer ice hydrometeor scatterers in the cloud model-generated profiles as compared with observed profiles. Direct comparisons between aircraft- measured and model-generated 2a12 microphysics suggest that, on average, the radiometer algorithm's microphysics database retrieves liquid and ice water contents that are approximately 1/3 the size of those observed at levels below 10 km. Also, the 2a12 rain-rate retrievals are shown to be strongly influenced by the 2a12's convective fraction specification. A proposed modification of this factor would improve 2a12 rain-rate retrievals; however, fundamental changes to the cloud radiation model's ice parameterization are necessary to overcome the algorithm's tendency to produce mixed-phase-layer ice hydrometeor deficits. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Smith, EA (reprint author), NASA, Goddard Space Flight Ctr, Code 613-6, Greenbelt, MD 20771 USA. EM eric.a.smith@nasa.gov NR 35 TC 12 Z9 12 U1 0 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1558-8424 J9 J APPL METEOROL CLIM JI J. Appl. Meteorol. Climatol. PD MAY PY 2006 VL 45 IS 5 BP 754 EP 786 DI 10.1175/JAM2336.1 PG 33 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 055GF UT WOS:000238437400007 ER PT J AU Hirshon, JM Weiss, SR LoCasale, R Levine, E Blaisdell, CJ AF Hirshon, JM Weiss, SR LoCasale, R Levine, E Blaisdell, CJ TI Looking beyond urban/rural differences: Emergency department utilization by asthmatic children SO JOURNAL OF ASTHMA LA English DT Article DE asthma; emergency departments; geographic variability; Maryland; children ID AIR-POLLUTION; RESPIRATORY-DISEASE; UNITED-STATES; RATES AB Asthma causes pediatric morbidity throughout the US with substantial regional variability. Emergency department (ED) utilization data were studied to determine if geographic variability of pediatric asthma cases exists within a state. Records for non-neonatal Maryland children less than 18 years of age seen and discharged from Maryland EDs from April 1997 through March 2001 were analyzed. While Baltimore City had the highest rates of asthma visits, adjusted odds ratios identified the wealthiest suburban county to have a higher risk of an asthma ED visit. Children from rural counties, for the most part, had fewer ED asthma visits than children from urban and suburban counties. C1 Univ Maryland, Sch Med, Dept Surg, Div Emergency Med, Baltimore, MD 21201 USA. Univ Maryland, Sch Med, Dept Epidemiol & Prevent Med, Baltimore, MD 21201 USA. Univ Maryland, Sch Pharm, Ctr Drugs & Publ Policy, Baltimore, MD 21201 USA. Univ Maryland, Sch Pharm, Dept Pharmaceut Hlth Serv Res, Baltimore, MD 21201 USA. Univ Maryland, Sch Med, Dept Pediat, Baltimore, MD 21201 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hirshon, JM (reprint author), Charles Mcc Mathias Jr Natl Study Ctr Trauma & EM, Dept Surg, Div Emergency Med, 701 W Pratt St,Room 524, Baltimore, MD 21201 USA. EM jhirs001@umaryland.edu OI Hirshon, Jon Mark/0000-0002-5247-529X NR 18 TC 6 Z9 6 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0277-0903 J9 J ASTHMA JI J. Asthma PD MAY PY 2006 VL 43 IS 4 BP 301 EP 306 DI 10.1080/02770900600623255 PG 6 WC Allergy; Respiratory System SC Allergy; Respiratory System GA 040NV UT WOS:000237386600009 PM 16809244 ER PT J AU Holz, RE Ackerman, S Antonelli, P Nagle, F Knuteson, RO McGill, M Hlavka, DL Hart, WD AF Holz, RE Ackerman, S Antonelli, P Nagle, F Knuteson, RO McGill, M Hlavka, DL Hart, WD TI An improvement to the high-spectral-resolution CO2-slicing cloud-top altitude retrieval SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID LASER MEASUREMENTS; SOUNDER; HEIGHTS; LIDAR AB An improvement to high-spectral-resolution infrared cloud-top altitude retrievals is compared to existing retrieval methods and cloud lidar measurements. The new method, CO2 sorting, determines optimal channel pairs to which the CO2 slicing retrieval will be applied. The new retrieval is applied to aircraft Scanning High-Resolution Interferometer Sounder (S-HIS) measurements. The results are compared to existing passive retrieval methods and coincident Cloud Physics Lidar (CPL) measurements. It is demonstrated that when CO2 sorting is used to select channel pairs for CO2 slicing there is an improvement in the retrieved cloud heights when compared to the CPL for the optically thin clouds (total optical depths less than 1.0). For geometrically thick but tenuous clouds, the infrared retrieved cloud tops underestimated the cloud height, when compared to those of the CPL, by greater than 2.5 km. For these cases the cloud heights retrieved by the S-HIS correlated closely with the level at which the CPL-integrated cloud optical depth was approximately 1.0. C1 Univ Wisconsin, CIMSS, Madison, WI USA. Goddard Space Flight Ctr, Greenbelt, MD USA. RP Holz, RE (reprint author), 1225 W Dayton,SSEC, Madison, WI 53706 USA. EM reholz@ssec.wisc.edu RI Ackerman, Steven/G-1640-2011; McGill, Matthew/D-8176-2012; OI Ackerman, Steven/0000-0002-4476-0269; Hlavka, Dennis/0000-0002-2976-7243 NR 22 TC 35 Z9 36 U1 2 U2 9 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAY PY 2006 VL 23 IS 5 BP 653 EP 670 DI 10.1175/JTECH1877.1 PG 18 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 060EM UT WOS:000238785200002 ER PT J AU Alvarez, JM Vaughan, MA Hostetler, CA Hunt, WH Winker, DM AF Alvarez, JM Vaughan, MA Hostetler, CA Hunt, WH Winker, DM TI Calibration technique for polarization-sensitive lidars SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID AIRBORNE LIDAR; CLOUD; DEPOLARIZATION; PARAMETERS; CAMPAIGN; PHASE AB Polarization-sensitive lidars have proven to be highly effective in discriminating between spherical and nonspherical particles in the atmosphere. These lidars use a linearly polarized laser and are equipped with a receiver that can separately measure the components of the return signal polarized parallel and perpendicular to the outgoing beam. In this work a technique for calibrating polarization-sensitive lidars is described that was originally developed at NASA's Langley Research Center (LaRC) and has been used continually over the past 15 yr. The procedure uses a rotatable half-wave plate inserted into the optical path of the lidar receiver to introduce controlled amounts of polarization cross talk into a sequence of atmospheric backscatter measurements. Solving the resulting system of nonlinear equations generates the system calibration constants (gain ratio and offset angle) required for deriving calibrated measurements of depolarization ratio from the lidar signals. In addition, this procedure also determines the mean depolarization ratio within the region of the atmosphere that is analyzed. Simulations and error propagation studies show the method to be both reliable and well behaved. Operational details of the technique are illustrated using measurements obtained as part of LaRC's participation in the First International Satellite Cloud Climatology Project Regional Experiment. C1 Sci Applicat Int Corp, NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Vaughan, MA (reprint author), Sci Applicat Int Corp, NASA, Langley Res Ctr, Mail Stop 475, Hampton, VA 23681 USA. EM m.a.vaughan@larc.nasa.gov NR 36 TC 39 Z9 40 U1 1 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAY PY 2006 VL 23 IS 5 BP 683 EP 699 DI 10.1175/JTECH1872.1 PG 17 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 060EM UT WOS:000238785200004 ER PT J AU Ridley, BA Avery, MA Plant, JV Vay, SA Montzka, DD Weinheimer, AJ Knapp, DJ Dye, JE Richard, EC AF Ridley, B. A. Avery, M. A. Plant, J. V. Vay, S. A. Montzka, D. D. Weinheimer, A. J. Knapp, D. J. Dye, J. E. Richard, E. C. TI Sampling of chemical constituents in electrically active convective systems: Results and cautions SO JOURNAL OF ATMOSPHERIC CHEMISTRY LA English DT Article DE PEM-tropics B; CRYSTAL-FACE; lightning; aircraft discharges; ozone; nitric oxide; carbon monoxide ID EXTREME OZONE CONCENTRATIONS; MARCH-APRIL 1999; AIRCRAFT OBSERVATIONS; NITROGEN-OXIDES; THUNDERSTORMS; TRANSPORT; NOX; PARTICLES; RADIATION; DISCHARGE AB On flights of a P3-B turboprop and a WB-57F jet aircraft within thunderstorm systems, short term spikes (1-2 sec or less in duration) in NO and O-3 were recorded and are attributed to hot or cold discharges occurring on the aircraft fuselage or air sampling inlets. One such spike of only similar to 300 msec duration reached 325 ppbv of NO on the flight of the jet aircraft while at 13.8 km altitude. In a lightning flash to the P3-B aircraft, production of NO (expected) and NO2 (unexpected) were directly observed. The NO production was similar to 1.7 x 10(22) molecules/m of flash length. In the P3-B flight at 5.5 km altitude and over a distance of similar to 275 km within a highly electrically active thunderstorm complex in the equatorial central Pacific Ocean, there was no evidence of production of O-3 or CO by lightning flashes or by any type of hot or cold discharge involved in the development of free-air lightning flashes. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NASA, Chem & Dynam Branch, Langley Res Ctr, Hampton, VA 23665 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. RP Ridley, BA (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM ridley@ucar.edu NR 29 TC 7 Z9 7 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-7764 EI 1573-0662 J9 J ATMOS CHEM JI J. Atmos. Chem. PD MAY PY 2006 VL 54 IS 1 BP 1 EP 20 DI 10.1007/s10874-005-9007-5 PG 20 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 068EE UT WOS:000239354400001 ER PT J AU Bauer, M Del Genio, AD AF Bauer, Mike Del Genio, Anthony D. TI Composite analysis of winter cyclones in a GCM: Influence on climatological humidity SO JOURNAL OF CLIMATE LA English DT Article ID NORTHERN-HEMISPHERE WINTER; UPPER-TROPOSPHERIC HUMIDITY; WATER-VAPOR; INTERANNUAL VARIABILITY; EXTRATROPICAL CYCLONES; ATMOSPHERIC RIVERS; CLOUD PROPERTIES; REANALYSIS DATA; STORM TRACK; PACIFIC AB The role of midlatitude baroclinic cyclones in maintaining the extratropical winter distribution of water vapor in an operational global climate model is investigated. A cyclone identification and tracking algorithm is used to compare the frequency of occurrence, propagation characteristics, and composite structure of 10 winters of storms in the Goddard Institute for Space Studies general circulation model (GCM) and in two reanalysis products. Cyclones are the major dynamical source of water vapor over the extratropical oceans in the reanalyses. The GCM produces fewer, generally weaker, and slower-moving cyclones than the reanalyses and is especially deficient in storms associated with secondary cyclogenesis. Composite fields show that GCM cyclones are shallower and drier aloft than those in the reanalyses and that their vertical structure is less tilted in the frontal region because of the GCM's weaker ageostrophic circulation. This is consistent with the GCM's underprediction of midlatitude cirrus. The GCM deficiencies do not appear to be primarily due to parameterization errors, the model is too dry despite producing less storm precipitation than is present in the reanalyses and in an experimental satellite precipitation dataset, and the weakness and shallow structure of GCM cyclones is already present at storm onset. These shortcomings may be common to most climate GCMs that do not resolve the mesoscale structure of frontal zones, and this may account for some universal problems in climate GCM midlatitude cloud properties. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Dept Earth & Environm Sci, New York, NY USA. RP Del Genio, AD (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM adelgenio@giss.nasa.gov RI Del Genio, Anthony/D-4663-2012 OI Del Genio, Anthony/0000-0001-7450-1359 NR 70 TC 40 Z9 41 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD MAY 1 PY 2006 VL 19 IS 9 BP 1652 EP 1672 DI 10.1175/JCLI3690.1 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 043US UT WOS:000237628300004 ER PT J AU Indeje, M Ward, MN Ogallo, LJ Davies, G Dilley, M Anyamba, A AF Indeje, M Ward, MN Ogallo, LJ Davies, G Dilley, M Anyamba, A TI Predictability of the normalized difference vegetation index in Kenya and potential applications as an indicator of Rift Valley Fever outbreaks in the Greater Horn of Africa SO JOURNAL OF CLIMATE LA English DT Article ID SEASONAL CLIMATE FORECASTS; NINO SOUTHERN OSCILLATION; SEA-SURFACE TEMPERATURE; EL-NINO; EASTERN AFRICA; SHORT RAINS; RAINFALL; MODEL; VARIABILITY; ENSO AB In this paper the progress made in producing predictions of the Normalized Difference Vegetation index (NDVI) over Kenya in the Greater Horn of Africa (GHA) for the October-December (OND) season is discussed. Several studies have identified a statistically significant relationship between rainfall and NDVI in the region. Predictability of seasonal rainfall by global climate models (GCMs) during the OND season over the GHA has also been established as being among the best in the world. Information was extracted from GCM seasonal prediction output using statistical transformations. The extracted information was then used in the prediction of NDVI. NDVI is a key variable for management of various climate-sensitive problems. For example. it has been shown to have the potential to predict environmental conditions associated with Rift Valley Fever (RVF) viral activity and this is referred to throughout the paper as a motivation for the study. RVF affects humans and livestock and is particularly economically important in the GHA. The establishment of predictability for NDVI in this paper is therefore part of a methodology that could ultimately generate information useful for managing RVF in livestock in the GHA. It has been shown that NDVI can be predicted skillfully over the GHA with a 2-3-month lead time. Such information is crucial for tailoring forecast information to support RVF monitoring and prediction over the region, as well as many other potential applications (e.g., livestock forage estimation). More generally, the Famine Early Warning System (FEWS). a project of the U.S. Agency for International Development (USAID) and the National Aeronautics and Space Administration (NASA) and other specialized technical centers routinely use NDVI images to monitor environmental conditions worldwide. The high predictability for NDVI established in this paper could therefore supplement the routine monitoring of environmental conditions for a wide range of applications. C1 Columbia Univ, Earth Inst, Int Res Inst Climate & Soc, Palisades, NY 10964 USA. IGAD Climate Predict & Applicat Ctr, Nairobi, Kenya. Vet Res Lab, Late SVRO, Kabete, Kenya. UMBC, Goddard Earth Sci Technol Ctr, Greenbelt, MD USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. RP Indeje, M (reprint author), Columbia Univ, Earth Inst, Int Res Inst Climate & Soc, 61 Route 9W, Palisades, NY 10964 USA. EM mindeje@iri.columbia.edu NR 41 TC 14 Z9 16 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAY 1 PY 2006 VL 19 IS 9 BP 1673 EP 1687 DI 10.1175/JCLI3708.1 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 043US UT WOS:000237628300005 ER PT J AU Dong, XQ Xi, BK Minnis, P AF Dong, XQ Xi, BK Minnis, P TI A climatology of midlatitude continental clouds from the ARM SGP central facility. Part II: Cloud fraction and surface radiative forcing SO JOURNAL OF CLIMATE LA English DT Article ID SOLAR-RADIATION; BUDGET EXPERIMENT; RADAR; EARTH; UNCERTAINTIES; VARIABILITY; ABSORPTION; ATMOSPHERE; MODELS; ALBEDO AB Data collected at the Department of Energy Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Central Facility (SCF) are analyzed to determine the monthly and hourly variations of cloud fraction and radiative forcing between January 1997 and December 2002. Cloud fractions are estimated for total cloud cover and for single-layered low (0-3 km), middle (3-6 km), and high Clouds (> 6 km) using ARM SCF ground-based paired lidar-radar measurements. Shortwave (SW) and longwave (LW) fluxes are derived from up- and down-looking standard precision spectral pyranometers and precision infrared radiometer measurements with uncertainties of similar to 10 W m(-2). The annual averages of total and single-lavered low-, middle-, and high-cloud fractions are 0.49, 0.11, 0.03, and 0.17, respectively. Both total- and low-cloud amounts peak during January and February and reach a minimum during July and August: high clouds occur more frequently than other types of clouds with a peak in summer. The average annual downwelling, surface SW fluxes for total and low clouds (151 and 138 W m(-2), respectively) are less than those under middle and high clouds (188 and 201 W m(-2). respectively), but the downwelling LW fluxes (349 and 356 W m(-2)) underneath total and low clouds are greater than those from middle and high clouds (337 and 333 W m(-2)). Low clouds produce the largest LW warming (55 W m(-2)) and SW cooling (-91 W m(-2)) effects with maximum and minimum absolute values in spring and summer, respectively. High clouds have the smallest LW warming (17 W m(-2)) and SW cooling (-37 W m(-2)) effects at the surface. All-sky SW cloud radiative forcing (CRF) decreases and LW CRF increases with increasing cloud fraction with mean slopes of -0.984 and 0.616 W m(-2) %(-1), respectively. Over the entire diurnal cycle, clouds deplete the amount of surface insolation more than they add to the downwelling LW flux. The calculated CRFs do not appear to be significantly affected by uncertainties in data sampling and clear-sky screening. Traditionally. cloud radiative forcing includes not only the radiative impact of the hydrometeors, but also the changes in the environment. Taken together over the ARM SCF, changes in humidity and surface albedo between clear and cloudy conditions offset similar to 20% of the NET radiative forcing caused by the cloud hydrometeors alone. Variations in water vapor, on average, account for 10% and 83% of the SW and LW CRFs, respectively, in total cloud cover conditions. The error analysis further reveals that the cloud hydrometeors dominate the SW CRF. white water vapor changes are most important for LW flux changes in cloudy skies. Similar studies over other locales are encouraged where water and surface albedo changes from clear to cloudy conditions may be much different than observed over the ARM SCF. C1 Univ N Dakota, Dept Atmospher Sci, Grand Forks, ND 58202 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Dong, XQ (reprint author), Univ N Dakota, Dept Atmospher Sci, 4149 Campus Rd,Box 9006, Grand Forks, ND 58202 USA. EM dong@aero.und.edu RI Minnis, Patrick/G-1902-2010; OI Minnis, Patrick/0000-0002-4733-6148; Dong, Xiquan/0000-0002-3359-6117 NR 34 TC 63 Z9 67 U1 2 U2 18 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD MAY 1 PY 2006 VL 19 IS 9 BP 1765 EP 1783 DI 10.1175/JCLI3710.1 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 043US UT WOS:000237628300011 ER PT J AU Liou, MS AF Liou, MS TI A sequel to AUSM, Part II: AUSM(+)-up for all speeds SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE upwind scheme; low Mach number; AUSM scheme; AUSM(+)-up; positivity; entropy-satisfying; carbuncle phenomenon; Euler and Navier-Stokes equations ID FLUX-SPLITTING METHODS; TURBULENCE MODELS; VISCOUS FLOWS; SCHEMES; SHOCK; EQUATIONS; ACCURATE AB In this paper, we present ideas and procedure to extend the AUSM-family schemes to solve flows at all speed regimes. To achieve this, we first focus on the theoretical development for the low Mach number limit. Specifically, we employ asymptotic analysis to formally derive proper scalings for the numerical fluxes in the limit of small Mach number. The resulting new scheme is shown to be simple and remarkably improved from previous schemes in robustness and accuracy. The convergence rate is shown to be independent of Mach number in the low Mach number regime up to M infinity = 0.5, and it is also essentially constant in the transonic and supersonic regimes. Contrary to previous findings, the solution remains stable, even if no local preconditioning matrix is included in the time derivative term, albeit a different convergence history may occur. Moreover, the new scheme is demonstrated to be accurate against analytical and experimental results. In summary, the new scheme, named AUSM(+)-up, improves over previous versions and eradicates fails found therein. 2005 Elsevier Inc. All rights reserved. C1 NASA, Turbomachinery & Prop Syst Div, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Liou, MS (reprint author), NASA, Turbomachinery & Prop Syst Div, Glenn Res Ctr, MS 5-11,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM MENG-SING.LIOU@grc.nasa.gov NR 43 TC 210 Z9 238 U1 7 U2 24 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY 1 PY 2006 VL 214 IS 1 BP 137 EP 170 DI 10.1016/j.jcp.2005.09.020 PG 34 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 027LP UT WOS:000236417400008 ER PT J AU Volz, MP Schweizer, M Raghothamachar, B Dudley, M Szoke, J Cobb, SD Szofran, FR AF Volz, MP Schweizer, M Raghothamachar, B Dudley, M Szoke, J Cobb, SD Szofran, FR TI X-ray characterization of detached-grown germanium crystals SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE defects; X-ray diffraction; X-ray topography; detached bridgman technique; semiconducting germanium ID BRIDGMAN GROWTH; SURFACE-TENSION; SOLIDIFICATION; MICROGRAVITY; MELTS; ANGLE; CDTE AB Germanium (I I I)-oriented crystals have been grown by the vertical Bridgman technique, in both detached and attached configurations. Microstructural characterization of these crystals has been performed using synchrotron white beam X-ray topography (SWBXT) and double axis X-ray diffraction. Dislocation densities were measured from X-ray topographs obtained using the reflection geometry. For detached-grown crystals, the dislocation density is on the order Of 10(4)cm(-2) in the seed region, and decreases in the direction of growth to less than 10(3) cm(-2), and in some crystals reaches less than 10(2) cm(-2). For crystals grown in the attached configuration, dislocation densities were on the order Of 10(4) cm(-2) in the middle of the crystals, increasing to greater than 105 cm(-2) near the edge. The measured dislocation densities are in excellent agreement with etch pit density (EPD) results. Broadening and splitting of the rocking curve linewidths was observed in the vicinity of subgrain boundaries identified by X-ray topography in some of the attached-grown crystal wafers. The spatial distribution of rocking curve linewidths across the wafers corresponds to the spatial distribution of defect densities measured in the X-ray topographs and EPD micrographs. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NASA, Marshall Space Flight Ctr, USRA, Huntsville, AL 35812 USA. SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. RP Volz, MP (reprint author), NASA, Marshall Space Flight Ctr, XD42, Huntsville, AL 35812 USA. EM Martin.Volz@nasa.gov RI Raghothamachar, Balaji/B-1094-2008 NR 19 TC 3 Z9 3 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY 1 PY 2006 VL 290 IS 2 BP 446 EP 451 DI 10.1016/j.jcrysgro.2006.01.025 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 037OM UT WOS:000237156400025 ER PT J AU Nori, V Lerma, N Gustavsson, J Segal, C Fernandez, R AF Nori, V Lerma, N Gustavsson, J Segal, C Fernandez, R TI Forced oscillations in a mixed-compression inlet at Mach 3.5 for pulse detonation engine systems SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID DIFFUSER FLOWS AB The effects of oscillatory backpressure on the air induction system for pulse detonation engines were examined for a two-dimensional, mixed-compression configuration at a freestream Mach number of 3.5. The pressure perturbations at the diffuser exit were produced by injecting air through four ports located at the corners of the exit cross section. The frequency, coupling of the-ports and airflow rates through the ports were varied, simulating the operation of detonation tubes. A terminal normal shock in the diffuser oscillated in the excited inlet, causing large pressure fluctuation amplitudes at some locations. Large injection mass flows resulted in inlet flow oscillations throughout the inlet, increased the spillage, yet did not cause inlet unstart. C1 Univ Florida, Dept Mech & Aerosp Engn, Gainesville, FL 32611 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Nori, V (reprint author), Univ Florida, Dept Mech & Aerosp Engn, Gainesville, FL 32611 USA. NR 18 TC 3 Z9 4 U1 0 U2 10 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD MAY PY 2006 VL 128 IS 3 BP 494 EP 506 DI 10.1115/1.2174061 PG 13 WC Engineering, Mechanical SC Engineering GA 046RU UT WOS:000237829500011 ER PT J AU Chen, RH Ng, HK Speyer, JL Guntur, LS Carpenter, R AF Chen, RH Ng, HK Speyer, JL Guntur, LS Carpenter, R TI Health monitoring of a satellite system SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA Guidance Navigation and Control Conference CY AUG 16-19, 2004 CL Providence, RI SP AIAA ID FAULT-DETECTION FILTER; PROBABILITY RATIO TEST; FAILURE-DETECTION; REDUNDANCY; DESIGN AB A health monitoring system based on analytical redundancy is developed for satellites on elliptical orbits. Analytical redundancy, which reduces the need for hardware redundancy, uses the modeled dynamic relationship between system inputs and measured system outputs to form a residual process that is used for detecting and identifying faults. First, the dynamics of the satellite including orbital mechanics and attitude dynamics is modeled as a periodic system. Then, periodic fault detection filters are designed to detect and identify the satellite's actuator and sensor faults. In addition, parity equations are constructed using the algebraic redundant relationship among actuators and sensors. Furthermore, a residual processor is designed to generate the probability of each fault by using a sequential probability test. Finally, the health monitoring system, consisting of periodic fault detection filters, parity equations, and residual processor, is evaluated in the simulation in the presence of disturbances and uncertainty. C1 Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90095 USA. NASA, Goddard Space Flight Ctr, Flight Dynam Anal Branch, Greenbelt, MD 20771 USA. RP Chen, RH (reprint author), Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90095 USA. EM speyer@seas.ucla.edu NR 24 TC 9 Z9 9 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 2006 VL 29 IS 3 BP 593 EP 605 DI 10.2514/1.15012 PG 13 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 041WE UT WOS:000237486300010 ER PT J AU Nguyen, N Ardema, M AF Nguyen, N Ardema, M TI Predictive optimal control of a hyperbolic distributed model for a wind tunnel SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID PARABOLIC EQUATIONS AB A new optimal-control approach is described, based on first-order hyperbolic partial differential equations to investigate a Mach number control problem for a closed-circuit wind tunnel. The flow in the wind tunnel is modeled as a distributed system using the Euler equations and is controlled by a compressor at the system boundary. The control inputs, to the compressor are in turn controlled by a lumped-parameter system modeled by ordinary differential equations that represent,dynamics of a drive-motor system and an inlet guide vane system. Optimality conditions of these coupled distributed and lump-parameter systems are developed using variational principles to establish an adjoint formulation for the optimal-control problem. The results are applied to a design of a predictive linear-quadratic optimal control for stabilizing the Mach number during a disturbance in the wind tunnel. C1 NASA, Ames Res Ctr, Intelligent Syst Div, Moffett Field, CA 94035 USA. Santa Clara Univ, Dept Mech Engn, Santa Clara, CA 95053 USA. RP Nguyen, N (reprint author), NASA, Ames Res Ctr, Intelligent Syst Div, Mail Stop 269-1, Moffett Field, CA 94035 USA. NR 9 TC 2 Z9 2 U1 1 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 2006 VL 29 IS 3 BP 626 EP 634 DI 10.2514/1.15381 PG 9 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 041WE UT WOS:000237486300014 ER PT J AU Ganji, F Joshi, SS Bayard, DS AF Ganji, F Joshi, SS Bayard, DS TI Adaptive formation control for rovers traveling over unknown terrains SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID MULTIPLE SPACECRAFT; DECENTRALIZED CONTROL; VIRTUAL STRUCTURES; MOBILE ROBOTS; EXPLORATION; ARCHITECTURE; VEHICLES; FEEDBACK; PLATOONS; SYSTEMS AB A novel adaptive formation-control strategy for a group of rovers navigating over unknown terrain is presented. A leader-follower formation control architecture is employed. Direct adaptive control laws and a formation speed adaptation strategy are developed that 1) bring the rovers into a prescribed formation from arbitrary in-plane locations and 2) enable the group to navigate over unknown and changing terrain, while staying in formation in the presence of actuator saturation. On-line estimates of generic friction parameters account for terrain surface variations. The leader specifies a reference motion for the entire fleet, including both straight-line and turning maneuvers. In saturation events, the formation speed is reduced based on the maximum sustainable speed of the slowest saturated rover using internal fleet communication, allowing the formation error to stay bounded and small. A formal proof for asymptotic stability of the formation system under nonsaturated conditions is given. A simulation example is presented that demonstrates formation initialization, formation-keeping, and formation-switching in both actuator saturation and nonsaturation circumstances. C1 Univ Calif Davis, Dept Mech & Aeronaut Engn, Davis, CA 95616 USA. Jet Prop Lab, Guidance & Control Anal Grp, Pasadena, CA 91101 USA. RP Ganji, F (reprint author), Univ Calif Davis, Dept Mech & Aeronaut Engn, Davis, CA 95616 USA. EM maejoshi@ucdavis.edu NR 31 TC 4 Z9 4 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 2006 VL 29 IS 3 BP 714 EP 724 DI 10.2514/1.15230 PG 11 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 041WE UT WOS:000237486300023 ER PT J AU Grenon, SM Xiao, XS Hurwitz, S Sheynberg, N Kim, C Seely, EW Cohen, RJ Williams, GH AF Grenon, S. Marlene Xiao, Xinshu Hurwitz, Shelley Sheynberg, Natalie Kim, Christine Seely, Ellen W. Cohen, Richard J. Williams, Gordon H. TI Why is orthostatic tolerance lower in women than in men? Renal and cardiovascular responses to simulated microgravity and the role of midodrine SO JOURNAL OF INVESTIGATIVE MEDICINE LA English DT Article DE gender; orthostatic intolerance; renin-angiotensin-aldosterone system; autonomic function; leg venous compliance ID BODY NEGATIVE-PRESSURE; DOWN BED REST; GENDER-DIFFERENCES; SYSTEM-IDENTIFICATION; SPACEFLIGHT; INTOLERANCE; ENDOCRINE AB Background: Exposure to microgravity induces cardiovascular deconditioning, manifested by orthostatic intolerance (OI). We assessed the renal, cardioendocrine, and cardiovascular responses of women and men to simulated microgravity to examine the impact of gender on OI. Methods: Fifteen healthy female and 14 healthy male subjects were given a constant diet for 3 to 5 days, after which they underwent a tilt-stand test (pre-TST) and began 14 to 16 days of head-down tilt bed rest (HDTB), followed by a repeat tilt-stand test (post-TST). Female subjects began HDTB so that the post-TST was at the same time in their menstrual cycle as their pre-TST. Twenty-four-hour urine collections (daily), hormonal measurements, plethysmography, and cardiovascular system identification were performed. Results: The times to presyncope were significantly different for men and women before (p=.005) and after HDTB (p =.001), with all of the women but only 50% of the men experiencing presyncope during the pre-TST (p =.002) and all of the women but only 64% of the men experiencing presyncope during the post-TST. At baseline, the following differences between women and men were observed: women had higher serum aldosterone levels (p =.02), higher parasympathetic responsiveness (p=.01), lower sympathetic responsiveness (p=.05), and lower venous compliance (p=.05). Several parameters changed with HDTB in both men and women. In a double-blinded randomized trial, midodrine (5 mg orally) or placebo given to female subjects 1 hour before post-TST was ineffective in preventing OI. Conclusion: In conclusion, the frequency of OI is higher in women than in men and is not modified by midodrine at the dose used. This increased susceptibility is likely secondary to intrinsic basal differences in the activity of volume-mediated parasympathetic and adrenergic systems and in venous tone. Thus, approaches to reduce OI in women are likely to differ from those effective in men. C1 Brigham & Womens Hosp, Div Endocrinol Hypertens & Diabet, Boston, MA 02115 USA. MIT, Harvard Mit Div Hlth Sci & Technol, NASA, Ctr Quantitat Cardiovasc Physiol Modeling & Data, Cambridge, MA 02139 USA. McGill Univ, Dept Cardiothorac Surg, Montreal, PQ, Canada. RP Williams, GH (reprint author), Brigham & Womens Hosp, Div Endocrinol Hypertens & Diabet, 221 Longwood Ave, Boston, MA 02115 USA. EM gwilliams@partners.org FU NCRR NIH HHS [5M01RR02635] NR 40 TC 14 Z9 16 U1 0 U2 1 PU B C DECKER INC PI HAMILTON PA 50 KING STREET EAST, 2ND FLOOR, PO BOX 620, L C D 1, HAMILTON, ONTARIO L8N 3K7, CANADA SN 1081-5589 J9 J INVEST MED JI J. Invest. Med. PD MAY PY 2006 VL 54 IS 4 BP 180 EP 190 DI 10.2310/6650.2006.05064 PG 11 WC Medicine, General & Internal; Medicine, Research & Experimental SC General & Internal Medicine; Research & Experimental Medicine GA 081ZR UT WOS:000240356600010 PM 17152857 ER PT J AU Anselmi-Tamburini, U Kodera, Y Gasch, M Unuvar, C Munir, ZA Ohyanagi, M Johnson, SM AF Anselmi-Tamburini, U Kodera, Y Gasch, M Unuvar, C Munir, ZA Ohyanagi, M Johnson, SM TI Synthesis and characterization of dense ultra-high temperature thermal protection materials produced by field activation through spark plasma sintering (SPS): I. Hafnium Diboride SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID SINTERING/SYNTHESIS PROCESS; FUNDAMENTAL INVESTIGATIONS; OXIDATION AB The consolidation of HfB2 by sintering and reactive sintering using the field-activated process of the spark plasma sintering (SPS) method was investigated. Sintering of the diboride at 1900 degrees C under a pressure of 95 MPa did not result in dense materials. In contrast, reactive sintering at 1700 degrees C produced about 98% dense HfB2 with a 10 min hold at temperature. In contrast to previous observations, the reaction between the elements and the consolidation of the resulting diboride did not coincide, the latter occurring at a much higher temperature. The reaction mechanism between B and Hf during reactive sintering was investigated. Measured rates of growth of the HfB2 were found to be in agreement with calculated values from diffusion couple experiments, suggesting that the current did not play a significant role in the reactivity. (c) 2006 Springer Science + Business Media, Inc. C1 Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. Ryukoku Univ, Dept Chem Mat, Otsu, Shiga, Japan. Ryukoku Univ, High Tech Res Ctr, Otsu, Shiga, Japan. NASA, Ames Res Ctr, ELORET Corp, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Thermal Protect & Mat Syst Branch, Moffett Field, CA 94035 USA. RP Munir, ZA (reprint author), Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. NR 17 TC 34 Z9 35 U1 2 U2 17 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY PY 2006 VL 41 IS 10 BP 3097 EP 3104 DI 10.1007/s10853-005-2457-y PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 047CC UT WOS:000237856400044 ER PT J AU Arepalli, S AF Arepalli, S TI A special issue: Second Workshop on SWCNT Growth Mechanisms - Preface SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Editorial Material C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Arepalli, S (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RI Arepalli, Sivaram/A-5372-2010 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD MAY PY 2006 VL 6 IS 5 BP I EP IB DI 10.1166/jnn.2006.182 PG 3 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 049QA UT WOS:000238030200001 ER PT J AU Farhat, S Scott, CD AF Farhat, Samir Scott, Carl D. TI Review of the arc process modeling for fullerene and nanotube production SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT 2nd Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes (SWCNTs) CY APR 08-12, 2005 CL Richard E Smalley Inst, Houston, TX SP Roce Univ, NASA Johnson Space Ctr, Rice Univ, Ctr Nanoscale Sci & Technol HO Richard E Smalley Inst DE carbon; nanotubes; arc discharge; kinetics; modeling ID WALLED CARBON NANOTUBES; OPTICAL-EMISSION SPECTROSCOPY; HIGH-YIELD SYNTHESIS; LARGE-SCALE PRODUCTION; GAS-PHASE; LASER-ABLATION; CLUSTER IONS; ELECTRIC-ARC; DIAMETER CONTROL; MIXED CATALYSTS AB The arc process remains the easiest and cheapest technique to obtain significant quantities of single wall carbon nanotubes (SWCNTs) with excellent structural properties. These nanotubes are quite straight and present few topological defects. However, the major inconvenience of this process remains the difficult in situ control of the final material's purity and physical properties. The first NASA/Rice workshop on growth mechanisms was devoted to addressing some specific questions on how and where the nanotubes are formed in several processes including the arc. Further advancement requires a detailed understanding of the growth mechanisms of fullerene, nanotubes and soot and their connection with process parameters. This approach is not highly developed today because of the coupling made by non-equilibrium plasma with the nonlinear chemical system makes, in which rate coefficients and reactions are not well known and this makes modeling difficult. This article is an attempt to analyze the effect of the individual arc parameters yielding guidelines for building a mechanistic understanding of carbon based nanomaterial growth in the arc discharge. C1 Univ Paris 13, LIMHP, F-93430 Villetaneuse, France. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Farhat, S (reprint author), Univ Paris 13, LIMHP, 99 Ave Jean Baptiste Clement, F-93430 Villetaneuse, France. NR 145 TC 33 Z9 33 U1 1 U2 25 PU AMER SCIENTIFIC PUBLISHERS PI VALENCIA PA 26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA SN 1533-4880 EI 1533-4899 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD MAY PY 2006 VL 6 IS 5 BP 1189 EP 1210 DI 10.1166/jnn.2006.331 PG 22 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 049QA UT WOS:000238030200004 PM 16792347 ER PT J AU Gutsev, GL Mochena, MD Bauschlicher, CW AF Gutsev, G. L. Mochena, M. D. Bauschlicher, C. W., Jr. TI All-electron DFT modeling of SWCNT growth on iron catalysts from carbon monoxide feedstock SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT 2nd Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes (SWCNTs) CY APR 08-12, 2005 CL Richard E Smalley Inst, Houston, TX SP Roce Univ, NASA Johnson Space Ctr, Rice Univ, Ctr Nanoscale Sci & Technol HO Richard E Smalley Inst DE iron catalyst; density functional theory; CO disproportionation; carbon dimers; carbon trimers; Boudouard reaction ID DENSITY-FUNCTIONAL THEORY; SINGLE-WALLED NANOTUBES; GAS-PHASE PRODUCTION; GAUSSIAN-BASIS SETS; PHOTOELECTRON-SPECTROSCOPY; MOLECULAR-DYNAMICS; METAL CLUSTER; IONIZATION ENERGIES; HIPCO PROCESS; FE-N AB Electronic and geometrical structures of Fe4Cn(CO)(m) (n + m <= 6) and their singly negatively and positively charged ions are computed using density functional theory with generalized gradient approximation. Isomers with CO bonded directly to the cluster iron atoms and bonded to a carbon atom chemisorbed on the cluster surface are optimized for the Fe4C2CO, Fe4C2(CO)(2), Fe4C3CO, and Fe4C4CO series. Optimizations of a large number of differently shaped Fe4C4, Fe4C5, and Fe4C6 clusters are performed to find trends in preferable arrangement of carbon atoms, in particular, to determine the relative energetics of structures with single C atoms versus those with C-2 dimers or C-3 trimers. The computed total energies are used to estimate the energetics of the Boudouard disproportionation reactions Fe4Cn(CO)(m)+CO --> Fe4Cn+1 (CO)(m-1) + CO2. C1 Florida A&M Univ, Dept Phys, Tallahassee, FL 32307 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Gutsev, GL (reprint author), Florida A&M Univ, Dept Phys, Tallahassee, FL 32307 USA. NR 60 TC 3 Z9 3 U1 1 U2 5 PU AMER SCIENTIFIC PUBLISHERS PI VALENCIA PA 26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA SN 1533-4880 EI 1533-4899 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD MAY PY 2006 VL 6 IS 5 BP 1281 EP 1289 DI 10.1166/jnn.2006.175 PG 9 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 049QA UT WOS:000238030200011 PM 16792354 ER PT J AU Cau, M Dorval, N Cao, B Attal-Tretout, B Cochon, JL Loiseau, A Farhat, S Scott, CD AF Cau, M Dorval, N Cao, B Attal-Tretout, B Cochon, JL Loiseau, A Farhat, S Scott, CD TI Spatial evolutions of Co and Ni atoms during single-walled carbon nanotubes formation: Measurements and modeling SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT 2nd Workshop on Growth Mechanisms of Single-Wall Carbon Nanotubes (SWCNTs) CY APR 08-12, 2005 CL Richard E Smalley Inst, Houston, TX SP Roce Univ, NASA Johnson Space Ctr, Rice Univ, Ctr Nanoscale Sci & Technol HO Richard E Smalley Inst DE laser induced fluorescence; cobalt; nickel; C-2; C-3 radicals; carbon nanotube formation; chemical kinetics calculations ID GROWTH; NANOPARTICLES; VAPORIZATION; DYNAMICS AB Spatial investigations of nickel and cobalt atoms and of C-2 and C-3 radicals are performed by laser induced fluorescence (LIF) in a continuous CO2 laser-vaporization reactor during the synthesis of single-walled carbon nanotubes. The chemical composition of the gas vaporized from bimetallic Ni/Co catalysts-carbon targets is determined using a chemical kinetic model. In this model, the evolution of Ni and Co atoms is driven by kinetics of condensation/evaporation process of pure metal clusters. Metal-carbon clusters are assumed to form from soot particles (C-80) and 128-atom metal clusters. Spatial profiles of Ni and Co atoms obtained by LIF are compared with the calculations to validate the modeling and to adjust the input data. The value of the initial molar fraction of carbon-metal mixture diluted in helium is determined through a parametric study. Good agreement is found between the measured and the calculated evolution of Ni for a molar fraction of the helium diluent ranging from 10 to 15%. To fit the spatial profile of Co, the activation energy is adjusted in the evaporation rate, changing the cobalt dimer bond energy. The latter is found to be largely uncertain; and three values are tested: 167, 208, and 230 kJ . mol(-1). From comparison, the activation energy is found to be 208 kJ . mol(-1). However, the C-2 LIF profiles show that the depletion of C-2 is accelerated when cobalt is present. The observed Co evolutions suggest that small Co-C clusters are easier and/or faster to form compared to Ni-C clusters. C1 Off Natl Etud & Rech Aerosp, F-91761 Palaiseau, France. Off Natl Etud & Rech Aerosp, CNRS, LEM, F-92322 Chatillon, France. Univ Paris 13, LIMHP, F-93430 Villetaneuse, France. NASA, Johnson Space Ctr ES4, Houston, TX 77058 USA. RP Dorval, N (reprint author), Off Natl Etud & Rech Aerosp, Chemin Huniere, F-91761 Palaiseau, France. NR 22 TC 8 Z9 8 U1 1 U2 1 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD MAY PY 2006 VL 6 IS 5 BP 1298 EP 1308 DI 10.1166/jnn.2006.178 PG 11 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 049QA UT WOS:000238030200013 PM 16792356 ER PT J AU Jin, HQ Van der Wijngaart, RF AF Jin, HQ Van der Wijngaart, RF TI Performance characteristics of the multi-zone NAS parallel benchmarks SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article; Proceedings Paper CT 18th International Parallel and Distributed Processing Symposium (IPDPS 2004) CY APR, 2004 CL Santa Fe, NM DE multi-zone parallel benchmarks; parallel computers; hybrid programming; performance model AB We describe a new suite of computational benchmarks that models applications featuring multiple levels of parallelism. Such parallelism is often available in realistic flow computations on systems of meshes, but had not previously been captured in benchmarks. The new suite, named NPB (NAS parallel benchmarks) multi-zone, is derived from the NPB suite, and involves solving the application benchmarks LU, BT and SP on collections of loosely coupled discretization meshes. The solutions on the meshes are updated independently. but after each time step they exchange boundary value information. This strategy provides relatively easily exploitable coarse-grain parallelism between meshes. Three reference implementations are available: one serial, one hybrid using the message passing interface (MPI) and OpenMP, and another hybrid using a shared memory multi-level programming model (SMP+OpenMP). We examine the effectiveness of hybrid parallelization paradigms in these implementations on four different parallel computers. We also use an empirical formula to investigate the performance characteristics of the hybrid parallel codes. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA Ames Res Ctr, NASA Adv Supercomp Div, Moffett Field, CA 94035 USA. RP Jin, HQ (reprint author), NASA Ames Res Ctr, NASA Adv Supercomp Div, MS T27A-1, Moffett Field, CA 94035 USA. EM hjin@nas.nasa.gov; rob.vanderwijngaart@sun.com NR 10 TC 19 Z9 19 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0743-7315 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD MAY PY 2006 VL 66 IS 5 BP 674 EP 685 DI 10.1016/j.jpdc.2005.06.016 PG 12 WC Computer Science, Theory & Methods SC Computer Science GA 032XU UT WOS:000236810700007 ER PT J AU Ayguade, E Gonzalez, M Martorell X Jost, G AF Ayguade, E Gonzalez, M Martorell, X Jost, G TI Employing nested OpenMP for the parallelization of multi-zone computational fluid dynamics applications SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article; Proceedings Paper CT 18th International Parallel and Distributed Processing Symposium (IPDPS 2004) CY APR, 2004 CL Santa Fe, NM DE OpenMP; parallel programming models; nested parallelism; NAS benchmarks AB In this paper we describe the parallelization of the multi-zone code versions of the NAS Parallel Benchmarks employing multi-level OpenMP parallelism. For our study, we use the NanosCompiler that supports nesting of OpenMP directives and provides clauses to control the grouping of threads, load balancing, and synchronization. We report the benchmark results, compare the timings with those of different hybrid parallelization paradigms (MPI+OpenMP and PLP) and discuss OpenMP implementation issues that affect the performance of multi-level parallel applications. (c) 2005 Elsevier Inc. All rights reserved. C1 UPC, Ctr Europeu Parallelisme Barcelona, Barcelona 08034, Spain. NASA Ames Res Ctr, NAS Div, Moffett Field, CA 94035 USA. RP Ayguade, E (reprint author), UPC, Ctr Europeu Parallelisme Barcelona, Jordi Girona 1-3 Modul D6, Barcelona 08034, Spain. EM eduard@ac.upc.es RI Ayguade, Eduard/D-8933-2014; Martorell, Xavier/G-6120-2015 OI Ayguade, Eduard/0000-0002-5146-103X; Martorell, Xavier/0000-0002-0417-3430 NR 17 TC 8 Z9 9 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0743-7315 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD MAY PY 2006 VL 66 IS 5 BP 686 EP 697 DI 10.1016/j.jpdc.2005.06.019 PG 12 WC Computer Science, Theory & Methods SC Computer Science GA 032XU UT WOS:000236810700008 ER PT J AU Goyne, CP Rodriguez, CG Krauss, RH McDaniel, JC McClinton, CR AF Goyne, CP Rodriguez, CG Krauss, RH McDaniel, JC McClinton, CR TI Experimental and numerical study of a dual-mode scramjet combustor SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/AAAF 11th International Space Planes and Hypersonic Systems and Technologies Conference CY SEP 29-OCT 04, 2002 CL ORLEANS, FRANCE SP Amer Inst Aeronaut & Astronaut, AAAF AB A Mach 2, hydrogen-air combustor with an unswept 10-deg ramp fuel injector was experimentally and numerically studied for a simulated flight Mach number near 5. Numerical modeling was performed using the Viscous Upwind Algorithm for Complex Flow Analysis code, and results were compared against experimental wall-pressure distributions, fuel plume images, and fuel plume velocity measurements. The model matched wall-pressure distributions well for the case of fuel-off and fuel-air mixing. For a fuel-air reacting case, pressure was matched well in the upstream third of the duct. Downstream, however, the pressure rise as a result of combustion was underpredicted. Based on the fuel plume imaging and velocity measurements,, fuel plume shape was matched well for both the mixing and reacting cases. However, plume size, penetration, and centerplane axial growth were generally underpredicted by the model. The full extent of the velocity reduction caused by thermal choking was also not predicted. Despite these, findings, the numerical model performed better than a previous model developed by the investigators. It was proposed that differences between the present numerical model and experiment stemmed from numerical underprediction of fuel-air turbulent mixing, and this resulted in underprediction of heat release. C1 Univ Virginia, Dept Mech & Aerosp Engn, Charlottesville, VA 22904 USA. ATK, GASL, Hampton, VA 23681 USA. Univ Virginia, Aerosp Res Lab, Charlottesville, VA 22904 USA. NASA, Langley Res Ctr, Flight Vehicles & Syst Program Off, Hampton, VA 23665 USA. RP Goyne, CP (reprint author), Univ Virginia, Dept Mech & Aerosp Engn, Charlottesville, VA 22904 USA. NR 19 TC 16 Z9 16 U1 0 U2 9 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2006 VL 22 IS 3 BP 481 EP 489 DI 10.2514/1.13215 PG 9 WC Engineering, Aerospace SC Engineering GA 045VN UT WOS:000237770900001 ER PT J AU Georgiadis, NJ Rumsey, CL Yoder, DA Zaman, KBMQ AF Georgiadis, NJ Rumsey, CL Yoder, DA Zaman, KBMQ TI Turbulence modeling effects on calculation of lobed nozzle flowfields SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA 41st Aerospace Sciences Meeting CY JAN 06-09, 2003 CL RENO, NV SP Amer Inst Aeronaut & Astronaut ID NOISE; PREDICTIONS; FLOWS AB Two Reynolds-averaged Navier-Stokes solvers, CFL3D and WIND, are applied to the subsonic turbulent jet flowfield originating from a six-lobed nozzle, with emphasis placed on turbulence modeling effects. The turbulence models investigated include linear one-equation and two-equation models and nonlinear two-equation explicit algebraic stress model (EASM) formulations. Two nozzle operating points are investigated, corresponding to exit Mach numbers of 0.30 and 0.94. Comparisons of calculated mean axial velocities and turbulence intensities are made with experimental data. All of the turbulence models were deficient in predicting the initial mixing rate 'exhibited by the experimental data. The one-equation model provided the best agreement with experimental data in the near field of the jet. The linear two-equation models and a modified EASM provided better agreement with data in the farfield. The Mach 0.30 k-omega EASM calculation required a time-accurate calculation because of significant unsteadiness in the initial jet region, which is believed to be characteristic of the nozzle flow under consideration. C1 NASA, John H Glenn Res Ctr Lewis Field, Nozzle Branch, Cleveland, OH 44135 USA. NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. NASA, John H Glenn Res Ctr Lewis Field, Nozzle Branch, Cleveland, OH 44135 USA. RP Georgiadis, NJ (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Nozzle Branch, Cleveland, OH 44135 USA. NR 22 TC 12 Z9 12 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2006 VL 22 IS 3 BP 567 EP 575 DI 10.2514/1.17160 PG 9 WC Engineering, Aerospace SC Engineering GA 045VN UT WOS:000237770900011 ER PT J AU Cassibry, JT Thio, YCF Markusic, TE Wu, ST AF Cassibry, JT Thio, YCF Markusic, TE Wu, ST TI Numerical modeling of a pulsed electromagnetic plasma thruster experiment SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID FIELD MAGNETOPLASMADYNAMIC THRUSTERS; OPENING SWITCH; PART 1; CONDUCTION; MACH2; CODE; FLUX; GUN AB We assessed the behavior and capabilities of a two-dimensional magnetohydrodynamic modeling code with a new tabular equation of state model for high-power pulsed plasma thrusters. The numerical results enabled detailed interpretation of the experimental data from a similar to 10-kJ pulsed coaxial plasma accelerator with ablative breech insulator pplytetrafluoroethylene. Our analysis showed that the initial conditions and ablation rate are critical to the behavior of the current sheet evolution in the numerical model. Qualitative agreement was obtained between the two-dimensional numerical model and experimental results, but there were significant quantitative discrepancies. The two-dimensional model indicates that some of the current remains trapped near the breech, because of the ablation of material off the breech boundary, Which appears to be supported by the experimental data. The sensitivity of the model to initial prefill density (small in comparison with the ablated mass) and ablation rate suggests that future modeling efforts involving high-power ablative fed pulsed plasma thrusters using the approach discussed in the paper should include a first-principles ablation model, together with density, temperature, and ablation rate estimates from the experimental apparatus. C1 Univ Alabama, Huntsville, AL 35899 USA. US DOE, Germantown, MD 20874 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Cassibry, JT (reprint author), Univ Alabama, Huntsville, AL 35899 USA. RI Thio, Yong Chia/G-5442-2014 OI Thio, Yong Chia/0000-0003-3615-643X NR 42 TC 4 Z9 7 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2006 VL 22 IS 3 BP 628 EP 636 DI 10.2514/1.16215 PG 9 WC Engineering, Aerospace SC Engineering GA 045VN UT WOS:000237770900019 ER PT J AU Chavers, DG Chang-Diaz, FR Irvine, C Squire, JP AF Chavers, DG Chang-Diaz, FR Irvine, C Squire, JP TI Momentum and heat flux measurements using an impact target in flowing plasma SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB An impact target plate was used to determine the momentum and heat flux quantities from a helicon plasma source. The plasma source is the first stage of the Variable Specific Impulse Magnetoplasma Rocket, which uses radio frequency waves to create and energize a flowing plasma. The momentum, and heat flux quantities are determined separately and agree favorably. They also agree with expected flux quantities calculated from the plasma parameters determined by other probes. The momentum and heat flux quantities were obtained at two axial locations in the exhaust or magnetic nozzle region of the device using helium and argon propellant. Only data from the plasma source are used,which shows that the plasma source does produce a flowing plasma with significant momentum. The flux data at the two axial locations verify the increase in momentum as the plasma flows through the diverging magnetic field in the magnetic nozzle region. Although the axial location for maximum momentum (or thrust) was not determined, forces of several millinewtons were measured for a combined neutral particle and plasma flow. The ionization fraction for these data was approximately 22%. Neutral particles entrained in the flow provided a significant part of the flow momentum thereby contributing to the potential thrust. The technique of measuring the momentum flux and heat flux in a flowing plasma is described. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Muniz Engn, Houston, TX 77058 USA. RP Chavers, DG (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 13 TC 7 Z9 7 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2006 VL 22 IS 3 BP 637 EP 644 DI 10.2514/1.1971 PG 8 WC Engineering, Aerospace SC Engineering GA 045VN UT WOS:000237770900020 ER PT J AU Blandino, J McDevitt, M Mueller, J Bame, D Green, A AF Blandino, J McDevitt, M Mueller, J Bame, D Green, A TI Characterization of dryout point in the vaporizing liquid microthruster SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 39th Joint Propulsion Conference CY JUL 20, 2003 CL Huntsville, AL SP AIAA, ASME, SAE, ASEE AB A specially designed vaporizing liquid microthruster (VLM) with a Pyrex cover glass to provide optical access has been used to investigate the two-phase flow of water through the heated channel, which is approximately 700 mu m wide and 300 mu m deep. The design and calibration of a feed system to control mass flow to the VLM in the range of 75-250 mu g/s is described along with the video microscopy system used for optical imaging of the phase transition within the channel. Images are presented showing the How structure during the initial vapor formation, a pulsing mode of operation, and unsteady interaction between individual vapor packets within the channel. As the flow rate is increased from 135-175 mu g/s at a heater power of 0.85 W, the location of phase boundary (dryout point) is found to move downstream by approximately 1 mm. Two candidate flow instabilities that could account for the observed unsteady behavior are discussed as well. C1 Worcester Polytech Inst, Worcester, MA 01609 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Blandino, J (reprint author), Worcester Polytech Inst, Worcester, MA 01609 USA. NR 15 TC 1 Z9 1 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2006 VL 22 IS 3 BP 677 EP 683 DI 10.2514/1.16179 PG 7 WC Engineering, Aerospace SC Engineering GA 045VN UT WOS:000237770900025 ER PT J AU Volchko, SJ Sung, CJ Huang, YM Schneider, SJ AF Volchko, SJ Sung, CJ Huang, YM Schneider, SJ TI Catalytic combustion of rich methane/oxygen mixtures for micropropulsion applications SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 41st Joint Propulsion Conference CY JUL 10-13, 2005 CL Tucson, AZ SP AIAA, ASME, SAE, ASEE ID CHEMISTRY; THRUSTER AB In an effort to aid the development of micropropulsion devices with a thrust level of 1-10 mN, as required by the next generation of miniaturized satellites and spacecraft, the combustion of rich methane/oxygen propellant mixtures in platinum microtubes with inside diameters of 0.4 and 0.8 mm is characterized. All of the mixtures tested had equivalence ratios beyond the corresponding rich flammability limits. Experimental results show that catalytic reactions could support combustion in mixtures even when gas-phase chemistry does not play a significant role. The effects of varying equivalence ratio, pressure, mass flow rate, and tube diameter on the critical temperature leading to catalytic ignition are systematically investigated. Furthermore, the effects of doping the methane/oxygen mixture with hydrogen are explored, demonstrating a substantial reduction in the ignition temperature with hydrogen addition. Microtube performance in terms of available thrust, specific impulse, and power required for preheating the microtube are also discussed. By the use of a plug flow model, the experimental conditions are simulated with detailed gas-phase/surface chemistry, thermodynamic properties, and transport properties. The computational results generally support the experimental findings. C1 Case Western Reserve Univ, Cleveland, OH 44106 USA. NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Volchko, SJ (reprint author), Case Western Reserve Univ, Cleveland, OH 44106 USA. EM sxv29@case.edu; cjs15@case.edu; yxh29@case.edu; Schneider@grc.nasa.gov NR 36 TC 16 Z9 18 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2006 VL 22 IS 3 BP 684 EP 693 DI 10.2514/1.19809 PG 10 WC Engineering, Aerospace SC Engineering GA 045VN UT WOS:000237770900026 ER PT J AU Schmidl, W Mikatarian, R Lam, CW West, B Buchanan, V Dee, L Baker, D Koontz, S AF Schmidl, W Mikatarian, R Lam, CW West, B Buchanan, V Dee, L Baker, D Koontz, S TI N-nitrosodimethylamine release from fuel oxidizer reaction product contaminated extravehicular activity suits SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT 7th International Conference on Protection of Materials and Structures from Space Environment (ICPMSE-7) CY 2004 CL Toronto, CANADA AB Before extravehicular activity (EVA) on the Russian segment (RS) of the International Space Station (ISS), the docking compartment (DC1) must be depressurized, because it is used as an airlock. It is preferred to use the U.S. control moment gyros (CMGs) instead of attitude-control thruster firings to compensate for disturbances and to maintain the ISS vehicle attitude. However, when the DC1 is depressurized, the CMGs' margin of momentum is insufficient to compensate for the disturbance and the service module (SM) attitude-control thrusters' need to fire to desaturate the CMGs. The SM roll-control thruster firings induce fuel-oxidizer reaction products (FORP) contamination on the adjacent SM surfaces around the thrusters. One of the components present in FORP is the potent carcinogen N-nitrosodimethylamine (NDMA). Because the EVA crewmembers often enter the area surrounding the thrusters for tasks on the aft end of the SM and when translating to other areas of the RS, the presence of FORP contamination is a concern. FORP contamination of the SM surfaces is discussed, along with the potential release of NDMA in a humid environment from crew EVA suits, whether they happen to be contaminated with FORP, the toxicological risk associated with the NDMA release, and the implementation of flight rules to mitigate the hazard. C1 Boeing Co, Boeing ISS Environm, Houston, TX 77059 USA. Wyle Labs, Dept Toxicol, Houston, TX 77058 USA. Hamilton Sundstrand, Johnson Space Ctr, EVA Off, ISS EVA Increment Management, Houston, TX 77058 USA. Honeywell Technol Solut, Las Cruces, NM 88004 USA. NASA, White Sands Test Facil, Las Cruces, NM 88004 USA. NASA, Lyndon B Johnson Space Ctr, ISS Environm, Houston, TX 77058 USA. RP Schmidl, W (reprint author), Boeing Co, Boeing ISS Environm, M-C HB3-20 77059,13100 Space Ctr Blvd, Houston, TX 77059 USA. NR 3 TC 1 Z9 1 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAY-JUN PY 2006 VL 43 IS 3 BP 557 EP 564 DI 10.2514/1.15041 PG 8 WC Engineering, Aerospace SC Engineering GA 055SM UT WOS:000238470700017 ER PT J AU Pinter, DJ Merceret, FJ Hatley, CV AF Pinter, DJ Merceret, FJ Hatley, CV TI Performance validation of upgraded eastern range 50-megahertz Doppler radar wind profiler SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT 7th International Conference on Protection of Materials and Structures from Space Environment (ICPMSE-7) CY 2004 CL Toronto, CANADA ID RESOLUTION C1 Raytheon Co, Comp Sci, Syst Anal, Patrick AFB, FL 32925 USA. NASA, Kennedy Space Ctr, YAD Weather Off, Kennedy Space Ctr, FL 32899 USA. ITT Ind, Patrick AFB, FL 32925 USA. RP Pinter, DJ (reprint author), Raytheon Co, Comp Sci, Syst Anal, POB 4127, Patrick AFB, FL 32925 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAY-JUN PY 2006 VL 43 IS 3 BP 693 EP 695 DI 10.2514/1.19660 PG 3 WC Engineering, Aerospace SC Engineering GA 055SM UT WOS:000238470700034 ER PT J AU Latournerie, J Dempsey, P Hourlier-Bahloul, D Bonnet, JP AF Latournerie, J Dempsey, P Hourlier-Bahloul, D Bonnet, JP TI Silicon oxycarbide glasses: Part 1 - Thermochemical stability SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID TRANSMISSION ELECTRON-MICROSCOPY; ENERGY-LOSS SPECTROSCOPY; OXYNITRIDE GLASSES; PHASE-SEPARATION; CARBIDE; PRECURSORS; CARBON; GEL; OXIDATION; FIBERS AB Silicon oxycarbide glasses (Si/C/O) of various compositions have been obtained after pyrolysis of polysiloxane gels produced by the sol-gel method. Four gels were synthesized from various structures of silicon precursors: MTES issued from methyltriethoxysilane CH3Si(-OEt)(3), VTES from vinyltriethoxysilane CH2=CH-Si(-OEt)(3), PTES from phenyltriethoxysilane C6H5-Si(-OEt)(3) and (DTH)-T-H 1/9 for that issued from the 1/9 molar ratio of methyldiethoxysilane D-H (CH3)HSi-(OEt)(2) and T-H triethoxysilane HSi(-OEt)(3). The resulting materials at 1000 degrees C can be described as an oxycarbide phase with the presence of either an excess of carbon or silicon depending on the starting structure of the precursor used to prepare the gels. By thermogravimetric analysis (TGA) coupled with mass spectrometry (MS), we followed the thermal behavior of each compound from 1000 degrees to 1500 degrees C. Based on these results and chemical analysis data, we have established the main reactions that occur during the decomposition of the oxycarbide glasses. At low temperature (T < 1400 degrees C), the dominant mechanism for carbon-rich materials first involves a solid-state reaction of SiO2 and C leading to SiC formation and removal of CO. That reaction proceeds at high temperature (above 1400 degrees C), as long as the amount of carbon in the material is high enough (PTES). When the system is depleted of its free carbon (VTES, MTES), however, another reaction can also proceed parallel to the former one, where SiO2 and SiC react leading to a loss of SiO and CO. The combination of an excess of silicon and a dense state of the material improves the thermo-chemical stability of the silicon oxycarbide phase present in the (DTH)-T-H 1/9 glass. By placing the chemical compositions in the ternary Si-C-O diagram, we could then determine the evolution at high temperature of any system of mixed Si/C-x/O-y phases. C1 Univ Limoges, SPCTS, UMR 6638, F-87060 Limoges, France. ENSCI, GEMH, F-87065 Limoges, France. RP Hourlier-Bahloul, D (reprint author), NASA, George C Marshall Space Flight Ctr, BAE Syst Analyt Solut, Biol & Phys Sci Explorat SD46, Huntsville, AL 35812 USA. EM djamila.hourlier@wanadoo.fr NR 41 TC 21 Z9 24 U1 3 U2 26 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2006 VL 89 IS 5 BP 1485 EP 1491 DI 10.1111/j.1551-2916.2005.00869.x PG 7 WC Materials Science, Ceramics SC Materials Science GA 038VP UT WOS:000237257900002 ER PT J AU Morscherz, GN Pujar, VV AF Morscherz, GN Pujar, VV TI Creep and stress-strain behavior after creep for SiC fiber reinforced, melt-infiltrated SiC matrix composites SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SILICON-CARBIDE; FATIGUE; CRACKING AB Silicon carbide fiber (Hi-Nicalon Type S, Nippon Carbon) reinforced silicon carbide matrix composites containing melt-infiltrated silicon were subjected to creep at 1315 degrees C at three different stress conditions. For the specimens that did not rupture after 100 h of tensile creep, fast-fracture experiments were performed immediately following the creep test at the creep temperature (1315 degrees C) or after cooling to room temperature. All specimens demonstrated excellent creep resistance and compared well to the creep behavior published in the literature on similar composite systems. Tensile results on the after-creep specimens showed that the matrix cracking stress actually increased, which is attributed to stress redistribution between composite constituents during tensile creep. C1 NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. Goodrich Corp, Mat & Simulat Ctr, Brecksville, OH 44141 USA. RP Pujar, VV (reprint author), NASA, Glenn Res Ctr, Ohio Aerosp Inst, MS 106-5, Cleveland, OH 44135 USA. EM vijay.pujar@goodrich.com OI Pujar, Vijay/0000-0003-0666-6842 NR 16 TC 14 Z9 14 U1 0 U2 3 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2006 VL 89 IS 5 BP 1652 EP 1658 DI 10.1111/j.1551-2916.2006.00939.x PG 7 WC Materials Science, Ceramics SC Materials Science GA 038VP UT WOS:000237257900029 ER PT J AU Malkova, N Ning, CZ AF Malkova, N Ning, CZ TI Ultrafast directional switching in photonic-crystal branched waveguides using electro-optical control SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID TRANSMISSION; BAND AB We propose and investigate ultrafast switching of light beams between different ports of a multibranch waveguide in photonic crystals. The branched waveguide is made of chains of coupled defects with degenerate states providing guided modes. Introduced at the corner of branches is a control cell made of an electro-optical active material. Depending on the symmetry of the refractive index changes, light propagation can be directed to specified direction. Dynamic changes of refractive index then provide ultrafast switching of light beams into a desired branch. (c) 2006 Optical Society of America C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Malkova, N (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM nmalkova@mail.arc.nasa.gov; cning@mail.arc.nasa.gov RI Ning, C. Z./D-4699-2009 OI Ning, C. Z./0000-0003-4583-8889 NR 19 TC 2 Z9 2 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 2006 VL 23 IS 5 BP 978 EP 985 DI 10.1364/JOSAB.23.000978 PG 8 WC Optics SC Optics GA 041EJ UT WOS:000237436000026 ER PT J AU Cucinotta, FA Durante, M AF Cucinotta, FA Durante, M TI Cancer risk from exposure to galactic cosmic rays: implications for space exploration by human beings SO LANCET ONCOLOGY LA English DT Article ID HZE-PARTICLE RADIATION; DOUBLE-STRAND BREAKS; IONIZING-RADIATION; HUMAN-LYMPHOCYTES; CHROMOSOME-ABERRATIONS; TELOMERE DYSFUNCTION; IRON IONS; HIGH-LET; DNA; CELL AB Space programmes are shifting toward planetary exploration, and in particular towards missions by human beings to the moon and Mars. However, exposure to space radiation is an important barrier to exploration of the solar system by human beings because of the biological effects of high-energy heavy ions. These ions have a high charge and energy, are the main contributors to radiation risk in deep space, and their biological effects are understood poorly. Predictions of the nature and magnitude of risks posed by exposure to radiation in space are subject to many uncertainties. In recent years, worldwide efforts have focussed on an increased understanding of the oncogenic potential of galactic cosmic rays. A review of the new results in this specialty will be presented here. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Naples Federico II, Dept Phys, Naples, Italy. Univ Naples Federico II, Natl Inst Nucl Phys, Naples, Italy. RP Cucinotta, FA (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM Francis.A.Cucinotta@nasa.gov RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 50 TC 276 Z9 285 U1 9 U2 34 PU LANCET LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 1470-2045 J9 LANCET ONCOL JI Lancet Oncol. PD MAY PY 2006 VL 7 IS 5 BP 431 EP 435 DI 10.1016/S1470-2045(06)70695-7 PG 5 WC Oncology SC Oncology GA 041XB UT WOS:000237488800029 PM 16648048 ER PT J AU Connolly, JF AF Connolly, JF TI One giant leap forward SO MECHANICAL ENGINEERING LA English DT Article C1 NASA, Lyndon B Johnson Space Ctr, New Lunar Lander Program, Houston, TX 77058 USA. RP Connolly, JF (reprint author), NASA, Lyndon B Johnson Space Ctr, New Lunar Lander Program, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0025-6501 J9 MECH ENG JI Mech. Eng. PD MAY PY 2006 VL 128 IS 5 BP 26 EP 31 PG 6 WC Engineering, Mechanical SC Engineering GA 040LT UT WOS:000237380800027 ER PT J AU Diaz, FJ Garcia, MR Melchor, T Montano, JG Sanchez, MA Najera, M Moreno, F Moreno, A Tovar, A Guerrero, H Hagan, DR AF Diaz, Francisco J. Refugio Garcia, Maria Melchor, Teresa Montano, Jose G. Sanchez, Marco A. Najera, Magdalena Moreno, Flora Moreno, Agustin Tovar, Antonio Guerrero, Humberto Hagan, Donald R. TI Prevalence and Trends in Metabolic Syndrome and Functional Aerobic Impairment in Adolescents, 1994-95, 2004-05 SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Diaz, Francisco J.; Refugio Garcia, Maria; Melchor, Teresa; Montano, Jose G.; Sanchez, Marco A.; Najera, Magdalena; Moreno, Flora; Moreno, Agustin; Tovar, Antonio; Guerrero, Humberto] Univ Guanajuato, Leon, Mexico. [Hagan, Donald R.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM msanchez@webtelmex.net.mx NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S200 EP S201 PG 2 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070802077 ER PT J AU Edwards, WB DeWitt, J Schaffner, G Hreljac, A Hagan, RD AF Edwards, W. Brent DeWitt, John Schaffner, Grant Hreljac, Alan Hagan, R. Donald TI Relationship Between External Load and Ground Reaction Force Parameters During Running in Weightlessness SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Edwards, W. Brent] Iowa State Univ, Ames, IA USA. [DeWitt, John] Bergaila Engn Serv, Houston, TX USA. [Schaffner, Grant] Wyle Life Sci, Houston, TX USA. [Hreljac, Alan] Calif State Univ Sacramento, Sacramento, CA 95819 USA. [Hagan, R. Donald] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM edwards9@iastate.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S391 EP S391 DI 10.1249/00005768-200605001-01655 PG 1 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070803052 ER PT J AU Norcross, J DeWitt, J Lee, SMC McCleary, F Edwards, WB Hagan, RD AF Norcross, Jason DeWitt, John Lee, Stuart M. C. McCleary, Frank Edwards, W. Brent Hagan, R. Donald TI Ground Reaction Forces and Gait Parameters during Motorized and Non-Motorized Treadmill Walking and Running on the International Space Station Treadmill SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Norcross, Jason; Lee, Stuart M. C.; McCleary, Frank] Wyle Labs, Houston, TX USA. [DeWitt, John] Bergaila Engn Serv, Houston, TX USA. [Edwards, W. Brent] LZ Technol, Houston, TX USA. [Hagan, R. Donald] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S122 EP S122 DI 10.1249/00005768-200605001-00564 PG 1 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070800479 ER PT J AU Powell, D Clowers, K Keefer, M Zhang, SN AF Powell, Douglas Clowers, Kurt Keefer, Maria Zhang, Songning TI Short-leg Walking Boots Alter Muscle Activation Patterns during Level Walking SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Powell, Douglas; Keefer, Maria; Zhang, Songning] Univ Tennessee, Knoxville, TN USA. [Clowers, Kurt] NASA, Lyndon B Johnson Space Ctr, Anthropometry & Biomech Facil, Houston, TX 77058 USA. EM dpowell4@utk.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S258 EP S258 DI 10.1249/00005768-200605001-01129 PG 1 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070802307 ER PT J AU Rodriguez, NR Gaine, PC Pikosky, MA Martin, WF Vislocky, LM Bolster, DR Ferrando, AA Wolfe, RR AF Rodriguez, Nancy R. Gaine, P. Courtney Pikosky, Matthew A. Martin, William F. Vislocky, Lisa M. Bolster, Douglas R. Ferrando, Arny A. Wolfe, Robert R. TI Gender Comparisons of Skeletal Muscle Protein Turnover Following an Endurance Exercise Bout SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Rodriguez, Nancy R.; Gaine, P. Courtney; Pikosky, Matthew A.; Martin, William F.; Vislocky, Lisa M.] Univ Connecticut, Storrs, CT USA. [Bolster, Douglas R.] NASA, USRA, Johnson Space Ctr, Houston, TX USA. [Ferrando, Arny A.; Wolfe, Robert R.] Univ Texas Med Branch, Galveston, TX USA. EM nancy.rodriguez@uconn.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S338 EP S338 DI 10.1249/00005768-200605001-01445 PG 1 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070802622 ER PT J AU Smith, CA Lee, SMC Laughlin, M Loehr, JA Norcross, J DeWitt, J Hagan, RD AF Smith, Cassie A. Lee, Stuart M. C. Laughlin, Mitzi Loehr, James A. Norcross, Jason DeWitt, John Hagan, R. Donald TI Physiologic Responses to Motorized and Non-Motorized Locomotion Utilizing the International Space Station Treadmill SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Smith, Cassie A.] JES Tech, Houston, TX USA. [Lee, Stuart M. C.; Laughlin, Mitzi; Loehr, James A.; Norcross, Jason] Wyle Labs, Houston, TX USA. [DeWitt, John] Bergaila Engn Serv, Houston, TX USA. [Hagan, R. Donald] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM csmith4@ems.jsc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S320 EP S320 DI 10.1249/00005768-200605001-01377 PG 1 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070802554 ER PT J AU Soller, BR Soyemi, O Landry, M Shear, M Wu, J Hagan, RD AF Soller, Babs R. Soyemi, Olusola Landry, Michelle Shear, Michael Wu, Jacqueline Hagan, R. Donald TI Validation of a New NIRS Method for Measuring Muscle Oxygenation during Rhythmic Handgrip Exercise SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Soller, Babs R.; Soyemi, Olusola; Landry, Michelle; Shear, Michael; Wu, Jacqueline] UMass Med Sch, Worcester, MA USA. [Hagan, R. Donald] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Soller, Babs R.] NIRStat LLC, Chatham, MA USA. EM babs.soller@umassmed.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S248 EP S249 PG 2 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070802271 ER PT J AU Zhang, SN Clowers, K Powell, D AF Zhang, Songning Clowers, Kurt Powell, Douglas TI Unique Joint Kinetic Patterns of Short-Leg Walkers in Gait SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Zhang, Songning; Powell, Douglas] Univ Tennessee, Knoxville, TN USA. [Clowers, Kurt] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM szhang@utk.edu OI Zhang, Songning/0000-0002-3712-9129 NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2006 VL 38 IS 5 SU S BP S172 EP S172 DI 10.1249/00005768-200605001-00782 PG 1 WC Sport Sciences SC Sport Sciences GA V19KH UT WOS:000208070801134 ER PT J AU Kimura, Y Nuth, JA Ferguson, FT AF Kimura, Yuki Nuth, Joseph A., III Ferguson, Frank T. TI Formation of TiC core-graphitic mantle grains from CO gas SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; CARBON NANOTUBES; MURCHISON METEORITE; NUCLEATION PROCESS; AMORPHOUS-CARBON; GROWTH; FULLERENES; PARTICLES; CONDENSATION; MECHANISM AB We demonstrate a new formation route for TiC core-graphitic mantle spherules that does not require carbon-atom addition and the very long time scales associated with such growth (Bernatowicz et al. 1996). Carbonaceous materials can be formed from C2H2 and its derivatives, as well as from CO gas. In this paper, we will demonstrate that large-cage-structure carbon particles can be produced from CO gas by the Boudouard reaction. Since the sublimation temperature for such fullerenes is low, the large cages can be deposited onto previously nucleated TiC and produce TiC core-graphitic mantle spherules. New constraints for the formation conditions and the time scale for the formation of TiC core-graphitic mantle spherules are suggested by the results of this study. In particular, TiC core-graphitic mantle grains that are found in primitive meteorites that have never experienced hydration Could be mantled by fullerenes or carbon nanotubes rather than by graphite. In situ observations of these grains in primitive anhydrous meteoritic matrix could confirm or refute this prediction and would demonstrate that the graphitic mantle on such grains is a metamorphic feature due to interaction of the presolar fullerenes with water within the meteorite matrix. C1 NASA, Goddard Space Flight Ctr, Astrochem Lab, Solar Syst Explorat Div, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Chem, Washington, DC 20064 USA. RP Kimura, Y (reprint author), NASA, Goddard Space Flight Ctr, Astrochem Lab, Solar Syst Explorat Div, Cose 691, Greenbelt, MD 20771 USA. EM ykimura@ssedmail.gsfc.nasa.gov RI Ferguson, Frank/C-9493-2012; Nuth, Joseph/E-7085-2012; Kimura, Yuki/J-9635-2014 OI Kimura, Yuki/0000-0002-9218-7663 NR 28 TC 2 Z9 2 U1 0 U2 5 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1086-9379 EI 1945-5100 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAY PY 2006 VL 41 IS 5 BP 673 EP 680 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 044LN UT WOS:000237674000002 ER PT J AU Elsila, JE Hammond, MR Bernstein, MP Sandford, SA Zare, RN AF Elsila, Jamie E. Hammond, Matthew R. Bernstein, Max P. Sandford, Scott A. Zare, Richard N. TI UV photolysis of quinoline in interstellar ice analogs SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; NITROGEN-HETEROCYCLIC COMPOUNDS; SIDE-GROUP ADDITION; MURCHISON METEORITE; CARBONACEOUS METEORITES; CAPILLARY ELECTROCHROMATOGRAPHY; ISOTOPIC CHARACTERIZATION; DEUTERIUM ENRICHMENT; MONOCARBOXYLIC ACIDS; ORGANIC-COMPOUNDS AB The polycyclic aromatic nitrogen heterocycle (PANH) quinoline (C(9)H(7)N) was frozen at 20 K in interstellar ice analogs containing either pure water or water mixed with methanol or methane and exposed to ultraviolet (UV) radiation. Upon warming, the photolysis products were analyzed by high-performance liquid chromatography and nanoscale liquid chromatography-electrospray ionization mass spectrometry. A suite of hydroxyquinolines, which were formed by the addition of oxygen atoms to quinoline, was observed as the primary product in all the ices. Quinoline N oxide was not formed, but five hydroxyquinoline isomers were produced with no clear dominance of one isomer. Reduction products, formed by hydrogen atom addition, were also created. Ices created at 20 K with H(2)O: quinoline ratios of 10:1 to 100:1 showed similar product distributions to those at 122 K, with no apparent temperature or concentration dependence. Increasing the UV dose led to a decrease in overall yield, indicating that quinoline and its products may be photo-destroyed. Methylquinolines were formed upon photolysis of the methanol- and methane-containing ices. In addition, possible methoxyquinolines or quinoline methylene alcohols were formed in the methanol-containing ice, while methylhydroxyquitiolines were created ill the methane-containing ice. This work indicates that oxidation of PANHs could occur in icy extraterrestrial environments and suggests that a search for such compounds in carbonaceous meteorites could illuminate the possible link between interstellar ice chemistry and meteoritic organics. Given the importance of oxidized and alkylated PANHs to biochemistry, the formation and delivery of such molecules to the early Earth may have played a role in the origin and evolution of life. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RP Elsila, JE (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. EM jelsila@mail.arc.nasa.gov RI Zare, Richard/A-8410-2009; Elsila, Jamie/C-9952-2012 NR 60 TC 25 Z9 25 U1 1 U2 9 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAY PY 2006 VL 41 IS 5 BP 785 EP 796 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 044LN UT WOS:000237674000011 ER PT J AU Nessel, JA Zaman, AJ Miranda, FA AF Nessel, JA Zaman, AJ Miranda, FA TI A miniaturized antenna for surface-to-surface and surface-to-orbiter applications SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE electrically small antennas; fractal antennas; multifrequency; miniature antennas; surface communications ID DESIGN AB A folded Hilbert curve fractal antenna (fHCFA) which produces end-fire radiation at the S-band and broadside radiation at the Ku-band without switches is presented. The measured gains/bandwidths were 12 dBi/10 MHz and 5.4 dBi/500 MHz at 2.3 GHz (S-band) and 16 8 GHz (Kit-band), respecively. This work offers a compact antenna design as a candidate for robotic applications, in future NASA planetary exploration missions. (c) 2006 Wiley Periodicals, Inc. C1 NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Nessel, JA (reprint author), NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. NR 11 TC 3 Z9 3 U1 0 U2 2 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0895-2477 J9 MICROW OPT TECHN LET JI Microw. Opt. Technol. Lett. PD MAY PY 2006 VL 48 IS 5 BP 859 EP 862 DI 10.1002/mop.21499 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 032XM UT WOS:000236809800011 ER PT J AU Shirley, JH AF Shirley, JH TI Axial rotation, orbital revolution and solar spin-orbit coupling SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE celestial mechanics; Sun : interior; Sun : magnetic fields; Sun : rotation ID INERTIAL MOTION; CYCLE AB The orbital motion of the Sun has been linked with solar variability, but the underlying physics remains unknown. A coupling of the solar axial rotation and the barycentric orbital revolution might account for the relationships found. Some recent published studies addressing the physics of this problem have made use of equations from rotational physics in order to model particle motions. However, our standard equations for rotational velocity do not accurately describe particle motions due to orbital revolution. The Sun's orbital motion is a state of free fall; in consequence, aside from very small tidal motions, the associated particle velocities do not vary as a function of position on or within the body of the Sun. In this note, I describe and illustrate the fundamental difference between particle motions in rotation and revolution, in order to dispel some part of the confusion that has arisen in the past and that which may yet arise in the future. This discussion highlights the principal physical difficulty that must be addressed and overcome by future dynamical spin-orbit coupling hypotheses. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Shirley, JH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 183-601, Pasadena, CA 91109 USA. EM James.H.Shirley@jpl.nasa.gov NR 14 TC 15 Z9 15 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 2006 VL 368 IS 1 BP 280 EP 282 DI 10.1111/j.1365-2966.2006.10107.x PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032TM UT WOS:000236797600038 ER PT J AU Xu, KM AF Xu, KM TI Using the bootstrap method for a statistical significance test of differences between summary histograms SO MONTHLY WEATHER REVIEW LA English DT Article ID EL-NINO; PRECIPITATION FORECASTS; HYPOTHESIS TESTS; CLOUD PROPERTIES; DISTANCE; PACIFIC; CERES AB A new method is proposed to compare statistical differences between summary histograms, which are the histograms summed over a large ensemble of individual histograms. It consists of choosing a distance statistic for measuring the difference between summary histograms and using a bootstrap procedure to calculate the statistical significance level. Bootstrapping is an approach to statistical inference that makes few assumptions about the underlying probability distribution that describes the data. Three distance statistics are compared in this study. They are the Euclidean distance, the Jeffries-Matusita distance, and the Kuiper distance. The data used in testing the bootstrap method are satellite measurements of cloud systems called "cloud objects." Each Cloud object is defined as a contiguous region/patch composed of individual footprints or fields of view. A histogram of measured values over footprints is generated for each parameter of each cloud object, and then summary histograms are accumulated over all individual histograms in a given cloud-object size category. The results of statistical hypothesis tests using all three distances as test statistics are generally similar, indicating the validity of the proposed method. The Euclidean distance is determined to be most suitable after comparing the statistical tests of several parameters with distinct probability distributions among three cloud-object size categories. Impacts on the statistical significance levels resulting from differences in the total lengths of satellite footprint data between two size categories are also discussed. C1 NASA, Langley Res Ctr, Climate Sci Branch, Hampton, VA 23681 USA. RP Xu, KM (reprint author), NASA, Langley Res Ctr, Climate Sci Branch, Mail Stop 420, Hampton, VA 23681 USA. EM Kuan-Man.Xu@nasa.gov RI Xu, Kuan-Man/B-7557-2013 OI Xu, Kuan-Man/0000-0001-7851-2629 NR 32 TC 13 Z9 13 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAY PY 2006 VL 134 IS 5 BP 1442 EP 1453 DI 10.1175/MWR3133.1 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 042VR UT WOS:000237559200007 ER PT J AU Kaul, AB Wong, EW Epp, L Hunt, BD AF Kaul, Anupama B. Wong, Eric W. Epp, Larry Hunt, Brian D. TI Electromechanical carbon nanotube switches for high-frequency applications SO NANO LETTERS LA English DT Article ID NANORELAY; GROWTH AB We describe the fabrication and characterization of a nanoelectromechanical (NEM) switch based on carbon nanotubes. Our NEM structure consists of single-walled nanotubes (SWNTs) suspended over shallow trenches in a SiO2 layer, with a Nb pull electrode beneath. The nanotube growth is done on-chip using a patterned Fe catalyst and a methane chemical vapor deposition (CVD) process at 850 degrees C. Electrical measurements of these devices show well-defined ON and OFF states as a dc bias up to a few volts is applied between the CNT and the Nb pull electrode. The CNT switches were measured to have speeds that are 3 orders of magnitude higher than MEMS-based electrostatically driven switches, with switching times down to a few nanoseconds, while at the same time requiring pull voltages less than 5 V. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kaul, AB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM anu.kaul@jpl.nasa.gov NR 24 TC 113 Z9 115 U1 2 U2 26 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD MAY PY 2006 VL 6 IS 5 BP 942 EP 947 DI 10.1021/nl052552r PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 043HY UT WOS:000237592900012 PM 16683830 ER PT J AU Savchenkov, AA Grudinin, IS Matsko, AB Strekalov, D Mohageg, M Chenko, VS Maleki, L AF Savchenkov, AA Grudinin, IS Matsko, AB Strekalov, D Mohageg, M Chenko, VS Maleki, L TI Morphology-dependent photonic circuit elements SO OPTICS LETTERS LA English DT Article AB We theoretically propose and experimentally demonstrate the design of a novel one-dimensional ringlike macroscopic optical circuit element. The similarity between morphologies of an optical planar waveguide and a whispering-gallery axially symmetric solid-state resonator is used. (c) 2006 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Savchenkov, AA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM andrey.matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 7 TC 39 Z9 39 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAY 1 PY 2006 VL 31 IS 9 BP 1313 EP 1315 DI 10.1364/OL.31.001313 PG 3 WC Optics SC Optics GA 036SL UT WOS:000237095600047 PM 16642096 ER PT J AU Greenberg, JA Dobrowski, SZ Ramirez, CM Tuil, JL Ustin, SL AF Greenberg, JA Dobrowski, SZ Ramirez, CM Tuil, JL Ustin, SL TI A bottom-up approach to vegetation mapping of the Lake Tahoe Basin using hyperspatial image analysis SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID MULTIRESOLUTION; MAPS AB Increasing demands on the accuracy and thematic resolution of vegetation community maps from remote sensing imagery has created a need Jar novel image analysis techniques. We present a case study for vegetation mapping of the Lake Tahoe Basin which fulfills many of the requirements of the Federal Geographic Data Committee base-level mapping (FGDC. 1997) by using hyperspatial Ikonos imagery analtyzed with a fusion of pixel-based species classification, automated image segmentation techniques to define vegetation patch boundaries, and vegetation community classification using querying of the species classification raster based on existing and novel rulesets. This technique led to accurate FGDC physiognomic classes. Floristic classes such as dominance type remain somewhat problematic due to inaccurate species classification results. Vegetation, tree and shrub cover estimates (FGDC required attributes) were determined accurately. We discuss strategies and challenges to vegetation community mapping in the context of standards currently being advanced for thematic attributes and accuracy requirements. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Calif Davis, CALSPACE, Davis, CA 95616 USA. USDA, Forest Serv, Forest Hlth Protect, McClellan, CA 95652 USA. RP Greenberg, JA (reprint author), NASA, Ames Res Ctr, MS 242-4, Moffett Field, CA 94035 USA. EM jgreenberg@arc.nasa.gov OI Greenberg, Jonathan/0000-0001-8435-9077 NR 20 TC 17 Z9 17 U1 1 U2 4 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 USA SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD MAY PY 2006 VL 72 IS 5 BP 581 EP 589 PG 9 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 042CI UT WOS:000237504400009 ER PT J AU Zuber, MT AF Zuber, MT TI Seconds of data ... Years of trying SO PHOTONICS SPECTRA LA English DT Article ID LASER ALTIMETER C1 MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zuber, MT (reprint author), MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. EM mtz@mit.edu NR 6 TC 4 Z9 4 U1 0 U2 0 PU LAURIN PUBL CO INC PI PITTSFIELD PA BERKSHIRE COMMON PO BOX 1146, PITTSFIELD, MA 01202 USA SN 0731-1230 J9 PHOTON SPECTRA JI Photon. Spect. PD MAY PY 2006 VL 40 IS 5 BP 56 EP + PG 5 WC Optics SC Optics GA 043GV UT WOS:000237589200019 ER PT J AU Florescu, M Scheel, S Lee, H Knight, PL Dowling, JP AF Florescu, M Scheel, S Lee, H Knight, PL Dowling, JP TI Nonlinear tuning of 3D photonic band-gap structures for single-photon on demand sources SO PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES LA English DT Article; Proceedings Paper CT 12th International Conference on Modulated Semiconductor Structures (MSS12) CY JUL 10-15, 2005 CL Albuquerque, NM DE photonic crystals; single-photon sources; linear optics quantum computation ID CAVITY-QUANTUM ELECTRODYNAMICS; SPONTANEOUS EMISSION; TURNSTILE DEVICE; DOT; CRYPTOGRAPHY; STATES AB We describe a practical implementation of a semi-deterministic photon gun based on the stimulated Raman adiabatic passage pumping and the nonlinear tuning of the photonic density of states in a photonic band-gap material. We show that this device allows deterministic and unidirectional production of single photons with a high repetition rate of the order of 100 kHz. We also discuss specific 3D photonic microstructure architectures in which our model can be realized and the feasibility of implementing such a device using Er3+ ions that produce single photons at the telecommunication wavelength of 1.55 mu m. (c) 2006 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ London Imperial Coll Sci & Technol, Blackett Lab, QOLS, London SW7 2BW, England. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. RP Florescu, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Marian.Florescu@jpl.nasa.gov RI Florescu, Marian/E-9009-2010; DOWLING, JONATHAN/L-2749-2013 NR 29 TC 4 Z9 4 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD MAY PY 2006 VL 32 IS 1-2 BP 484 EP 487 DI 10.1016/j.physe.2005.12.144 PG 4 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 046WQ UT WOS:000237842200123 ER PT J AU Florescu, L John, S Quang, T AF Florescu, L John, S Quang, T TI Emission properties of a single-emitter laser in photonic crystals SO PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES LA English DT Article; Proceedings Paper CT 12th International Conference on Modulated Semiconductor Structures (MSS12) CY JUL 10-15, 2005 CL Albuquerque, NM DE photonic crystals; single-atom lasers; quantum optics ID BAND-GAP; QUANTUM ELECTRODYNAMICS; CAVITY; ATOMS; EDGE; INVERSION AB We theoretically study a single-emitter laser in a photonic crystal. We consider a two-level atomic system coupled to a high-quality micro-cavity embedded within a photonic crystal and coherently pumped by an external laser field. We derive analytical expressions for the optical intensity and second order correlation function for the light emitted into the micro-cavity. The cavity field characteristics are highly distinct from that of a corresponding high-Q cavity in ordinary vacuum. We demonstrate enhanced, inversionless, nearly coherent light generation when the photon density of states of the photonic crystal presents a large discontinuity. (c) 2006 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Florescu, L (reprint author), CALTECH, Jet Prop Lab, NASA, MS 126-347,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM lucia.m.florescu@jpl.nasa.gov NR 21 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD MAY PY 2006 VL 32 IS 1-2 BP 488 EP 491 DI 10.1016/j.physe.2005.12.143 PG 4 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 046WQ UT WOS:000237842200124 ER PT J AU Cartoixa, X Wang, LW Ting, DZY Chang, YC AF Cartoixa, X. Wang, L. -W. Ting, D. Z. -Y. Chang, Y. -C. TI Higher-order contributions to Rashba and Dresselhaus effects SO PHYSICAL REVIEW B LA English DT Article ID GASB QUANTUM-WELLS; SPIN RELAXATION; ELECTRONIC-STRUCTURE; INVERSION ASYMMETRY; GALLIUM ANTIMONIDE; HOLE TRANSPORT; SURFACE-STATES; SEMICONDUCTORS; SUPERLATTICES; HETEROSTRUCTURES AB We have developed a method to systematically compute the form of Rashba- and Dresselhaus-like contributions to the spin Hamiltonian of heterostructures to an arbitrary order in the in-plane wave vector k(parallel to). This is achieved by using the double-group representations to construct general symmetry-allowed Hamiltonians with full spin-orbit effects within the tight-binding formalism. We have computed full-zone spin Hamiltonians for [001]-, [110]-, and [111]-grown zinc-blende heterostructures (D-2d,C-4v,C-2v,C-3v point-group symmetries), which are commonly used in spintronics. After an expansion of the Hamiltonian up to third order in k(parallel to), we are able to obtain additional terms not found previously. The present method also provides the matrix elements for bulk zinc blendes (T-d) in the anion-cation and effective bond orbital model (EBOM) basis sets with full spin-orbit effects. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. Univ Autonoma Barcelona, Dept Engn Electron, Barcelona 08193, Spain. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Cartoixa, X (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. EM Xavier.Cartoixa@uab.es RI Chang, Yia-Chung/F-4239-2011 NR 60 TC 29 Z9 29 U1 1 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY PY 2006 VL 73 IS 20 AR 205341 DI 10.1103/PhysRevB.73.205341 PG 11 WC Physics, Condensed Matter SC Physics GA 048MF UT WOS:000237950500077 ER PT J AU Abbott, B Abbott, R Adhikari, R Ageev, A Agresti, J Ajith, P Allen, B Allen, J Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cantley, CA Cao, J Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G Daw, E Debra, D Delker, T Dergachev, V Desai, S DeSalvo, R Dhurandhar, S Di Credico, A Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Goggin, L Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanna, C Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, G Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Luna, M Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mandic, V Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Melissinos, A Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, E Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robinson, C Robison, L Roddy, S Rodriguez, A Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Ruediger, A Ruet, L Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sarin, P Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sellers, D Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Spjeld, O Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sung, M Sutton, PJ Sylvestre, J Tanner, DB Tariq, H Tarallo, M Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ward, R Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Wette, K Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J Akutsu, T Akutsu, T Ando, M Arai, K Araya, A Asada, H Aso, Y Beyersdorf, P Fujiki, Y Fujimoto, MK Fujita, R Fukushima, M Futamase, T Hamuro, Y Haruyama, T Hayama, K Iguchi, H Iida, Y Ioka, K Ishitsuka, H Kamikubota, N Kanda, N Kaneyama, T Karasawa, Y Kasahara, K Kasai, T Katsuki, M Kawamura, S Kawamura, M Kawazoe, F Kojima, Y Kokeyama, K Kondo, K Kozai, Y Kudoh, H Kuroda, K Kuwabara, T Matsuda, N Mio, N Miura, K Miyama, S Miyoki, S Mizusawa, H Moriwaki, S Musha, M Nagayama, Y Nakagawa, K Nakamura, T Nakano, H Nakao, K Nishi, Y Numata, K Ogawa, Y Ohashi, M Ohishi, N Okutomi, A Oohara, K Otsuka, S Saito, Y Sakata, S Sasaki, M Sato, N Sato, S Sato, Y Sato, K Sekido, A Seto, N Shibata, M Shinkai, H Shintomi, T Soida, K Somiya, K Suzuki, T Tagoshi, H Takahashi, H Takahashi, R Takamori, A Takemoto, S Takeno, K Tanaka, T Taniguchi, K Tanji, T Tatsumi, D Telada, S Tokunari, M Tomaru, T Tsubono, K Tsuda, N Tsunesada, Y Uchiyama, T Ueda, K Ueda, A Waseda, K Yamamoto, A Yamamoto, K Yamazaki, T Yanagi, Y Yokoyama, J Yoshida, T Zhu, ZH AF Abbott, B. Abbott, R. Adhikari, R. Ageev, A. Agresti, J. Ajith, P. Allen, B. Allen, J. Amin, R. Anderson, S. B. Anderson, W. G. Araya, M. Armandula, H. Ashley, M. Asiri, F. Aufmuth, P. Aulbert, C. Babak, S. Balasubramanian, R. Ballmer, S. Barish, B. C. Barker, C. Barker, D. Barnes, M. Barr, B. Barton, M. A. Bayer, K. Beausoleil, R. Belczynski, K. Bennett, R. Berukoff, S. J. Betzwieser, J. Bhawal, B. Bilenko, I. A. Billingsley, G. Black, E. Blackburn, K. Blackburn, L. Bland, B. Bochner, B. Bogue, L. Bork, R. Bose, S. Brady, P. R. Braginsky, V. B. Brau, J. E. Brown, D. A. Bullington, A. Bunkowski, A. Buonanno, A. Burgess, R. Busby, D. Butler, W. E. Byer, R. L. Cadonati, L. Cagnoli, G. Camp, J. B. Cannizzo, J. Cannon, K. Cantley, C. A. Cao, J. Cardenas, L. Carter, K. Casey, M. M. Castiglione, J. Chandler, A. Chapsky, J. Charlton, P. Chatterji, S. Chelkowski, S. Chen, Y. Chickarmane, V. Chin, D. Christensen, N. Churches, D. Cokelaer, T. Colacino, C. Coldwell, R. Coles, M. Cook, D. Corbitt, T. Coyne, D. Creighton, J. D. E. Creighton, T. D. Crooks, D. R. M. Csatorday, P. Cusack, B. J. Cutler, C. Dalrymple, J. D'Ambrosio, E. Danzmann, K. Davies, G. Daw, E. DeBra, D. Delker, T. Dergachev, V. Desai, S. DeSalvo, R. Dhurandhar, S. Di Credico, A. Diaz, M. Ding, H. Drever, R. W. P. Dupuis, R. J. Edlund, J. A. Ehrens, P. Elliffe, E. J. Etzel, T. Evans, M. Evans, T. Fairhurst, S. Fallnich, C. Farnham, D. Fejer, M. M. Findley, T. Fine, M. Finn, L. S. Franzen, K. Y. Freise, A. Frey, R. Fritschel, P. Frolov, V. V. Fyffe, M. Ganezer, K. S. Garofoli, J. Giaime, J. A. Gillespie, A. Goda, K. Goggin, L. Gonzalez, G. Gossler, S. Grandclement, P. Grant, A. Gray, C. Gretarsson, A. M. Grimmett, D. Grote, H. Grunewald, S. Guenther, M. Gustafson, E. Gustafson, R. Hamilton, W. O. Hammond, M. Hanna, C. Hanson, J. Hardham, C. Harms, J. Harry, G. Hartunian, A. Heefner, J. Hefetz, Y. Heinzel, G. Heng, I. S. Hennessy, M. Hepler, N. Heptonstall, A. Heurs, M. Hewitson, M. Hild, S. Hindman, N. Hoang, P. Hough, J. Hrynevych, M. Hua, W. Ito, M. Itoh, Y. Ivanov, A. Jennrich, O. Johnson, B. Johnson, W. W. Johnston, W. R. Jones, D. I. Jones, G. Jones, L. Jungwirth, D. Kalogera, V. Katsavounidis, E. Kawabe, K. Kells, W. Kern, J. Khan, A. Killbourn, S. Killow, C. J. Kim, C. King, C. King, P. Klimenko, S. Koranda, S. Koetter, K. Kovalik, J. Kozak, D. Krishnan, B. Landry, M. Langdale, J. Lantz, B. Lawrence, R. Lazzarini, A. Lei, M. Leonor, I. Libbrecht, K. Libson, A. Lindquist, P. Liu, S. Logan, J. Lormand, M. Lubinski, M. Lueck, H. Luna, M. Lyons, T. T. Machenschalk, B. MacInnis, M. Mageswaran, M. Mailand, K. Majid, W. Malec, M. Mandic, V. Mann, F. Marin, A. Marka, S. Maros, E. Mason, J. Mason, K. Matherny, O. Matone, L. Mavalvala, N. McCarthy, R. McClelland, D. E. McHugh, M. McNabb, J. W. C. Melissinos, A. Mendell, G. Mercer, R. A. Meshkov, S. Messaritaki, E. Messenger, C. Mikhailov, E. Mitra, S. Mitrofanov, V. P. Mitselmakher, G. Mittleman, R. Miyakawa, O. Mohanty, S. Moreno, G. Mossavi, K. Mueller, G. Mukherjee, S. Murray, P. Myers, E. Myers, J. Nagano, S. Nash, T. Nayak, R. Newton, G. Nocera, F. Noel, J. S. Nutzman, P. Olson, T. O'Reilly, B. Ottaway, D. J. Ottewill, A. Ouimette, D. Overmier, H. Owen, B. J. Pan, Y. Papa, M. A. Parameshwaraiah, V. Parameswariah, C. Pedraza, M. Penn, S. Pitkin, M. Plissi, M. Prix, R. Quetschke, V. Raab, F. Radkins, H. Rahkola, R. Rakhmanov, M. Rao, S. R. Rawlins, K. Ray-Majumder, S. Re, V. Redding, D. Regehr, M. W. Regimbau, T. Reid, S. Reilly, K. T. Reithmaier, K. Reitze, D. H. Richman, S. Riesen, R. Riles, K. Rivera, B. Rizzi, A. Robertson, D. I. Robertson, N. A. Robinson, C. Robison, L. Roddy, S. Rodriguez, A. Rollins, J. Romano, J. D. Romie, J. Rong, H. Rose, D. Rotthoff, E. Rowan, S. Ruediger, A. Ruet, L. Russell, P. Ryan, K. Salzman, I. Sandberg, V. Sanders, G. H. Sannibale, V. Sarin, P. Sathyaprakash, B. Saulson, P. R. Savage, R. Sazonov, A. Schilling, R. Schlaufman, K. Schmidt, V. Schnabel, R. Schofield, R. Schutz, B. F. Schwinberg, P. Scott, S. M. Seader, S. E. Searle, A. C. Sears, B. Seel, S. Seifert, F. Sellers, D. Sengupta, A. S. Shapiro, C. A. Shawhan, P. Shoemaker, D. H. Shu, Q. Z. Sibley, A. Siemens, X. Sievers, L. Sigg, D. Sintes, A. M. Smith, J. R. Smith, M. Smith, M. R. Sneddon, P. H. Spero, R. Spjeld, O. Stapfer, G. Steussy, D. Strain, K. A. Strom, D. Stuver, A. Summerscales, T. Sumner, M. C. Sung, M. Sutton, P. J. Sylvestre, J. Tanner, D. B. Tariq, H. Tarallo, M. Taylor, I. Taylor, R. Taylor, R. Thorne, K. A. Thorne, K. S. Tibbits, M. Tilav, S. Tinto, M. Tokmakov, K. V. Torres, C. Torrie, C. Traylor, G. Tyler, W. Ugolini, D. Ungarelli, C. Vallisneri, M. van Putten, M. Vass, S. Vecchio, A. Veitch, J. Vorvick, C. Vyachanin, S. P. Wallace, L. Walther, H. Ward, H. Ward, R. Ware, B. Watts, K. Webber, D. Weidner, A. Weiland, U. Weinstein, A. Weiss, R. Welling, H. Wen, L. Wen, S. Wette, K. Whelan, J. T. Whitcomb, S. E. Whiting, B. F. Wiley, S. Wilkinson, C. Willems, P. A. Williams, P. R. Williams, R. Willke, B. Wilson, A. Winjum, B. J. Winkler, W. Wise, S. Wiseman, A. G. Woan, G. Woods, D. Wooley, R. Worden, J. Wu, W. Yakushin, I. Yamamoto, H. Yoshida, S. Zaleski, K. D. Zanolin, M. Zawischa, I. Zhang, L. Zhu, R. Zotov, N. Zucker, M. Zweizig, J. Akutsu, T. Akutsu, T. Ando, M. Arai, K. Araya, A. Asada, H. Aso, Y. Beyersdorf, P. Fujiki, Y. Fujimoto, M. -K. Fujita, R. Fukushima, M. Futamase, T. Hamuro, Y. Haruyama, T. Hayama, K. Iguchi, H. Iida, Y. Ioka, K. Ishitsuka, H. Kamikubota, N. Kanda, N. Kaneyama, T. Karasawa, Y. Kasahara, K. Kasai, T. Katsuki, M. Kawamura, S. Kawamura, M. Kawazoe, F. Kojima, Y. Kokeyama, K. Kondo, K. Kozai, Y. Kudoh, H. Kuroda, K. Kuwabara, T. Matsuda, N. Mio, N. Miura, K. Miyama, S. Miyoki, S. Mizusawa, H. Moriwaki, S. Musha, M. Nagayama, Y. Nakagawa, K. Nakamura, T. Nakano, H. Nakao, K. Nishi, Y. Numata, K. Ogawa, Y. Ohashi, M. Ohishi, N. Okutomi, A. Oohara, K. Otsuka, S. Saito, Y. Sakata, S. Sasaki, M. Sato, N. Sato, S. Sato, Y. Sato, K. Sekido, A. Seto, N. Shibata, M. Shinkai, H. Shintomi, T. Soida, K. Somiya, K. Suzuki, T. Tagoshi, H. Takahashi, H. Takahashi, R. Takamori, A. Takemoto, S. Takeno, K. Tanaka, T. Taniguchi, K. Tanji, T. Tatsumi, D. Telada, S. Tokunari, M. Tomaru, T. Tsubono, K. Tsuda, N. Tsunesada, Y. Uchiyama, T. Ueda, K. Ueda, A. Waseda, K. Yamamoto, A. Yamamoto, K. Yamazaki, T. Yanagi, Y. Yokoyama, J. Yoshida, T. Zhu, Z. -H. CA LIGO Sci Collaboration TAMA Collaboration TI Joint LIGO and TAMA300 search for gravitational waves from inspiralling neutron star binaries SO PHYSICAL REVIEW D LA English DT Article ID COALESCENCE RATES; COMPACT BINARIES; TELESCOPE; TEMPLATES; DETECTORS; EVENTS AB We search for coincident gravitational wave signals from inspiralling neutron star binaries using LIGO and TAMA300 data taken during early 2003. Using a simple trigger exchange method, we perform an intercollaboration coincidence search during times when TAMA300 and only one of the LIGO sites were operational. We find no evidence of any gravitational wave signals. We place an observational upper limit on the rate of binary neutron star coalescence with component masses between 1 and 3M of 49 per year per Milky Way equivalent galaxy at a 90% confidence level. The methods developed during this search will find application in future network inspiral analyses. C1 LIGO Calif Inst Technol, Pasadena, CA 91125 USA. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. Syracuse Univ, Syracuse, NY 13244 USA. Max Planck Inst Gravitat Phys, D-30167 Hannover, Germany. Univ Wisconsin, Milwaukee, WI 53201 USA. MIT, LIGO, Cambridge, MA 02139 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Univ Texas, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. Penn State Univ, University Pk, PA 16802 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. Albert Einstein Inst, Max Planck Inst Gravitationsphys, D-14476 Golm, Germany. Cardiff Univ, Cardiff CF2 3YB, Wales. LIGO Hanford Observ, Richland, WA 99352 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Stanford Univ, Stanford, CA 94305 USA. Northwestern Univ, Evanston, IL 60208 USA. LIGO Livingston Observ, Livingston, LA 70754 USA. Washington State Univ, Pullman, WA 99164 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Rochester, Rochester, NY 14627 USA. NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Florida, Gainesville, FL 32611 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Carleton Coll, Northfield, MN 55057 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Australian Natl Univ, Canberra, ACT 0200, Australia. Inter Univ Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. CALTECH, Pasadena, CA 91125 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. Embry Riddle Aeronaut Univ, Prescott, AZ 86301 USA. Max Planck Inst Quantenoptik, D-85748 Garching, Germany. Univ Illes Balears, E-07122 Palma De Mallorca, Spain. Vassar Coll, New York, NY 12604 USA. Salish Kootenai Coll, Pablo, MT 59855 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Trinity Univ, San Antonio, TX 78212 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. Univ Tokyo, Dept Astron, Tokyo 1130033, Japan. Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Natl Astron Observ Japan, Tokyo 1818588, Japan. Univ Tokyo, Earthquake Res Inst, Tokyo 1130032, Japan. Hirosaki Univ, Fac Sci & Technol, Hirosaki, Aomori 0368561, Japan. Niigata Univ, Fac Sci, Niigata 9502102, Japan. Osaka Univ, Grad Sch Sci, Toyonaka, Osaka 5600043, Japan. Tohoku Univ, Grad Sch Sci, Sendai, Miyagi 9808578, Japan. Tohoku Univ, Grad Sch Sci, Sendai, Miyagi 9808578, Japan. High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. Tokyo Inst Technol, Meguro Ku, Tokyo 1528551, Japan. Osaka City Univ, Grad Sch Sci, Sumiyoshi Ku, Osaka 5588585, Japan. Ochanomizu Univ, Tokyo 1128610, Japan. Hiroshima Univ, Dept Phys, Higashihiroshima 7398526, Japan. Kyoto Univ, Fac Sci, Sakyo Ku, Kyoto 6068502, Japan. Tokyo Denki Univ, Chiyoda Ku, Tokyo 1018457, Japan. Univ Tokyo, Dept Adv Mat Sci, Kashiwa, Chiba 2778561, Japan. Miyagi Univ Educ, Dept Phys, Sendai, Miyagi 9800845, Japan. Univ Electrocommun, Inst Laser Sci, Chofu, Tokyo 1828585, Japan. Tokai Univ, Fac Engn, Precis Engn Div, Hiratsuka, Kanagawa 2591292, Japan. Waseda Univ, Shinjyuku Ku, Tokyo 1698555, Japan. Univ Tokyo, Grad Sch Arts & Sci, Meguro Ku, Tokyo 1538902, Japan. RIKEN, Wako, Saitama 3510198, Japan. Kyoto Univ, Yukawa Inst Theoret Phys, Sakyo Ku, Kyoto 6068502, Japan. Univ Tokyo, Grad Sch Sci, Res Ctr Early Universe RESCEU, Tokyo 1130033, Japan. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058563, Japan. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Abbott, B (reprint author), LIGO Calif Inst Technol, Pasadena, CA 91125 USA. RI Freise, Andreas/F-8892-2011; Kawabe, Keita/G-9840-2011; Tarallo, Marco/B-2096-2012; Finn, Lee Samuel/A-3452-2009; Agresti, Juri/G-8168-2012; Taniguchi, Keisuke/G-2694-2011; Mitrofanov, Valery/D-8501-2012; Harms, Jan/J-4359-2012; Bilenko, Igor/D-5172-2012; Allen, Bruce/K-2327-2012; Chen, Yanbei/A-2604-2013; Barker, David/A-5671-2013; Pitkin, Matthew/I-3802-2013; Liu, Sheng/K-2815-2013; Vyatchanin, Sergey/J-2238-2012; van Putten, Maurice/F-5237-2011; ANDO, MASAKI/G-4989-2014; MIYAMA, Shoken/A-3598-2015; Vecchio, Alberto/F-8310-2015; Ottaway, David/J-5908-2015; Ottewill, Adrian/A-1838-2016; Messaritaki, Eirini/D-7393-2016; Sigg, Daniel/I-4308-2015; Frey, Raymond/E-2830-2016; Sylvestre, Julien/A-8610-2009; Beausoleil, Raymond/C-5076-2009; McClelland, David/E-6765-2010; Hild, Stefan/A-3864-2010; Schutz, Bernard/B-1504-2010; Casey, Morag/C-9703-2010; Rowan, Sheila/E-3032-2010; Strain, Kenneth/D-5236-2011; Raab, Frederick/E-2222-2011; Lueck, Harald/F-7100-2011; Kawazoe, Fumiko/F-7700-2011; Ward, Robert/I-8032-2014; OI Tarallo, Marco/0000-0001-5169-4987; Finn, Lee Samuel/0000-0002-3937-0688; Agresti, Juri/0000-0001-6119-2470; Allen, Bruce/0000-0003-4285-6256; Pitkin, Matthew/0000-0003-4548-526X; ANDO, MASAKI/0000-0002-8865-9998; Vecchio, Alberto/0000-0002-6254-1617; Ottewill, Adrian/0000-0003-3293-8450; Sigg, Daniel/0000-0003-4606-6526; Frey, Raymond/0000-0003-0341-2636; Sylvestre, Julien/0000-0001-8136-4348; McClelland, David/0000-0001-6210-5842; Strain, Kenneth/0000-0002-2066-5355; Lueck, Harald/0000-0001-9350-4846; Ward, Robert/0000-0001-5503-5241; Whelan, John/0000-0001-5710-6576; Stuver, Amber/0000-0003-0324-5735; Zweizig, John/0000-0002-1521-3397; Russell, Pamela/0000-0002-3995-1239; Fairhurst, Stephen/0000-0001-8480-1961; Aulbert, Carsten/0000-0002-1481-8319; Freise, Andreas/0000-0001-6586-9901; Whiting, Bernard F/0000-0002-8501-8669; Veitch, John/0000-0002-6508-0713; Nakano, Hiroyuki/0000-0001-7665-0796; Papa, M.Alessandra/0000-0002-1007-5298 NR 34 TC 39 Z9 39 U1 1 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAY PY 2006 VL 73 IS 10 AR 102002 DI 10.1103/PhysRevD.73.102002 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 048ML UT WOS:000237951100005 ER PT J AU Baker, JG Centrella, J Choi, DI Koppitz, M van Meter, J AF Baker, JG Centrella, J Choi, DI Koppitz, M van Meter, J TI Binary black hole merger dynamics and waveforms SO PHYSICAL REVIEW D LA English DT Article ID ADAPTIVE MESH REFINEMENT; INITIAL DATA AB We study dynamics and radiation generation in the last few orbits and merger of a binary black hole system, applying recently developed techniques for simulations of moving black holes. Our analysis of the gravitational radiation waveforms and dynamical black hole trajectories produces a consistent picture for a set of simulations with black holes beginning on circular-orbit trajectories at a variety of initial separations. We find profound agreement at the level of 1% among the simulations for the last orbit, merger and ringdown. We are confident that this part of our waveform result accurately represents the predictions from Einstein's General Relativity for the final burst of gravitational radiation resulting from the merger of an astrophysical system of equal-mass nonspinning black holes. The simulations result in a final black hole with spin parameter a/m=0.69. We also find good agreement at a level of roughly 10% for the radiation generated in the preceding few orbits. C1 NASA, Goddard Space Flight Ctr, Gravitat Astrophys Lab, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. RP Baker, JG (reprint author), NASA, Goddard Space Flight Ctr, Gravitat Astrophys Lab, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA. RI van meter, james/E-7893-2011 NR 28 TC 161 Z9 161 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 J9 PHYS REV D JI Phys. Rev. D PD MAY PY 2006 VL 73 IS 10 AR 104002 DI 10.1103/PhysRevD.73.104002 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 048ML UT WOS:000237951100033 ER PT J AU Parks, GK Lee, E Mozer, F Wilber, M Lucek, E Dandouras, I Reme, H Mazelle, C Cao, JB Meziane, K Goldstein, ML Escoubet, P AF Parks, GK Lee, E Mozer, F Wilber, M Lucek, E Dandouras, I Reme, H Mazelle, C Cao, JB Meziane, K Goldstein, ML Escoubet, P TI Larmor radius size density holes discovered in the solar wind upstream of Earth's bow shock SO PHYSICS OF PLASMAS LA English DT Article ID AMPLITUDE MAGNETIC-STRUCTURES; PARALLEL COLLISIONLESS SHOCKS; DIAMAGNETIC CAVITIES UPSTREAM; HOT FLOW ANOMALIES; CLUSTER OBSERVATIONS; CYCLIC BEHAVIOR; ELECTRIC-FIELD AB The Cluster and Double Star satellites recently observed plasma density holes upstream of Earth's collisionless bow shock to apogee distances of similar to 19 and 13 earth radii, respectively. A survey of 147 isolated density holes using 4 s time resolution data shows they have a mean duration of similar to 17.9 +/- 10.4 s, but holes as short as 4 s are observed. The average fractional density depletion (delta n/n) inside the holes is similar to 0.68 +/- 0.14. The upstream edge of density holes can have enhanced densities that are five or more times the solar wind density. Particle distributions show the steepened edge can behave like a shock. Multispacecraft analyses show the density holes move with the solar wind, can have an ion gyroradius scale, and could be expanding. A small normal electric field points outward. Similarly shaped magnetic holes accompany the density holes indicating strong coupling between fields and particles. The density holes are only observed with upstream particles, suggesting that backstreaming particles interacting with the solar wind are important.(c) 2006 American Institute of Physics. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ London Imperial Coll Sci & Technol, Blackett Lab, London, England. Univ Toulouse 3, Ctr Etud Spatiale Rayonnements, Toulouse, France. CAS, CSSAR, Key Lab Space Weather, Beijing, Peoples R China. Univ New Brunswick, Dept Phys, Fredericton, NB E3B 5A3, Canada. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. European Space Agcy, NL-2200 AG Noordwijk, Netherlands. RP Parks, GK (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RI Goldstein, Melvyn/B-1724-2008; Lee, Ensang/E-2356-2013; OI Dandouras, Iannis/0000-0002-7121-1118 NR 19 TC 26 Z9 29 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2006 VL 13 IS 5 AR 050701 DI 10.1063/1.2201056 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 048JI UT WOS:000237943000001 ER PT J AU Hinshaw, G AF Hinshaw, G TI WMAP data put cosmic inflation to the test SO PHYSICS WORLD LA English DT Article C1 NASA, Goddard Space Flight Ctr, WMAP Sci Team, Greenbelt, MD 20771 USA. RP Hinshaw, G (reprint author), NASA, Goddard Space Flight Ctr, WMAP Sci Team, Greenbelt, MD 20771 USA. EM gary.f.hinshaw@nasa.gov NR 0 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD MAY PY 2006 VL 19 IS 5 BP 16 EP 19 PG 4 WC Physics, Multidisciplinary SC Physics GA 046WD UT WOS:000237840900028 ER PT J AU Sato, T Kurumada, M Kamitsuji, K Kido, O Suzuki, H Shintaku, M Kimura, Y Saito, Y Kaito, C AF Sato, T Kurumada, M Kamitsuji, K Kido, O Suzuki, H Shintaku, M Kimura, Y Saito, Y Kaito, C TI Influence of plasma on formation of crystalline Fe2SiO4 grains SO PLANETARY AND SPACE SCIENCE LA English DT Article DE laboratory experiments; dusty plasma; grain size; dust particle; composition ID COMET HALE-BOPP; SILICATE DUST; DYNAMIC-BEHAVIOR; METAL PARTICLES; EVOLVED STARS; RF PLASMA; GROWTH; NANOPARTICLES; DISKS; IRON AB The production of Fe2SiO4 (fayalite) crystalline grains was performed by two processes, namely, grain formation in a plasma field by evaporating a mixture powder of Fe and SiO and heat treatment of the product collected on the radio-frequency (RF) electrode side. Fe grains < 20 nm in size covered with an amorphous SiO layer selectively formed Fe2SiO4 grains by heating at 800 degrees C. By heating at 600 degrees C, in addition to the formation of Fe2SiO4 crystal grains, the FeO phase appeared. The doping effect of excited oxygen in a plasma field into the Fe small grains may be the trigger on the formation of fayalite through the FeO phase formation. The present experimental result suggests that the probability Of Fe2SiO4 grain formation in space is low. (c) 2006 Published by Elsevier Ltd. C1 Ritsumeikan Univ, Dept Nanophys Frontier Phys, Shiga 5258577, Japan. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Kyoto Inst Technol, Dept Electron & Informat Sci, Kyoto 6068585, Japan. RP Sato, T (reprint author), Ritsumeikan Univ, Dept Nanophys Frontier Phys, 1-1-1,Nojihigashi, Shiga 5258577, Japan. EM kaito@se.ritsumei.ac.jp RI Kimura, Yuki/J-9635-2014 OI Kimura, Yuki/0000-0002-9218-7663 NR 29 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD MAY PY 2006 VL 54 IS 6 BP 612 EP 616 DI 10.1016/j.pss.2005.12.004 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 049MF UT WOS:000238019900006 ER PT J AU Sato, T Kamitsuji, K Shintaku, M Kimura, Y Kurumada, M Kido, O Suzuki, H Saito, Y Kaito, C AF Sato, T Kamitsuji, K Shintaku, M Kimura, Y Kurumada, M Kido, O Suzuki, H Saito, Y Kaito, C TI Laboratory analogy of crystalline enstatite grain formation in plasma field SO PLANETARY AND SPACE SCIENCE LA English DT Article DE laboratory experiments; dusty plasma; dust particle; composition ID SMOKE PARTICLES; COALESCENCE GROWTH; SILICA; FILM; MG AB Crystalline enstatite (MgSiO3) grains were produced by the simultaneous evaporation of SiO grains and Mg vapor in a plasma field. The MgSiO3 grains were spherical or needlelike. The necessity of a plasma field in astromineralogy is suggested in the present study. (c) 2006 Published by Elsevier Ltd. C1 Ritsumeikan Univ, Dept Nanophys Frontier Phys, Shiga 5258577, Japan. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Kyoto Inst Technol, Dept Electron & Informat Sci, Kyoto 6068585, Japan. RP Sato, T (reprint author), Ritsumeikan Univ, Dept Nanophys Frontier Phys, 1-1-1 Nojihigashi, Shiga 5258577, Japan. EM sato-t@se.ritsumei.ac.jp RI Kimura, Yuki/J-9635-2014 OI Kimura, Yuki/0000-0002-9218-7663 NR 17 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD MAY PY 2006 VL 54 IS 6 BP 617 EP 620 DI 10.1016/j.pss.2005.12.005 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 049MF UT WOS:000238019900007 ER PT J AU Ivanchenko, MG Coffeen, WC Lomax, TL Dubrovsky, JG AF Ivanchenko, MG Coffeen, WC Lomax, TL Dubrovsky, JG TI Mutations in the Diageotropica (Dgt) gene uncouple patterned cell division during lateral root initiation from proliferative cell division in the pericycle SO PLANT JOURNAL LA English DT Article DE lateral root initiation; pericycle; auxin; development; cyclophilin; tomato ID TOMATO MUTANT DIAGEOTROPICA; POLAR AUXIN TRANSPORT; ARABIDOPSIS-THALIANA; EXPRESSION; PLANT; MORPHOGENESIS; GROWTH; CYCLE; IMMUNOPHILINS; CYCLOPHILIN AB In angiosperms, root branching requires a continuous re-initiation of new root meristems. Through some unknown mechanism, in most eudicots pericycle cells positioned against the protoxylem change identity and initiate patterned division, leading to formation of lateral root primordia that further develop into lateral roots. This process is auxin-regulated. We have observed that three mutations in the Diageotropica (Dgt) gene in tomato prevent primordium formation. Detailed analysis of one of these mutants, dgt1-1, demonstrated that the mutation does not abolish the proliferative capacity of the xylem-adjacent pericycle in the differentiated root portion. Files of shortened pericycle cells found in dgt1-1 roots were unrelated to primordium formation. Auxin application stimulated this unusual proliferation, leading to formation of a multi-layered xylem-adjacent pericycle, but did not rescue the primordium formation. In contrast to wild type, auxin could not induce any cell divisions in the pericycle of the most distal dgt1-1 root-tip portion. In wild-type roots, the Dgt gene promoter was expressed strongly in lateral root primordia starting from their initiation, and on auxin treatment was induced in the primary root meristem. Auxin level and distribution were altered in dgt1-1 root tissues, as judged by direct auxin measurements, and the tissue-specific expression of an auxin-response reporter was altered in transgenic plants. Together, our data demonstrate that the Dgt gene product, a type-A cyclophilin, is essential for morphogenesis of lateral root primordia, and that the dgt mutations uncouple patterned cell division in lateral root initiation from proliferative cell division in the pericycle. C1 Oregon State Univ, Dept Bot & Plant Pathol, Corvallis, OR 97331 USA. NASA Headquarters, Explorat Syst Miss Directorate, Washington, DC 20546 USA. Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Biol Mol Plantas, Cuernavaca 62250, Morelos, Mexico. RP Ivanchenko, MG (reprint author), Oregon State Univ, Dept Bot & Plant Pathol, 2082 Cordley Hall, Corvallis, OR 97331 USA. EM ivanchem@science.oregonstate.edu RI Dubrovsky, Joseph/B-9479-2008 OI Dubrovsky, Joseph/0000-0002-2072-4650 NR 60 TC 43 Z9 45 U1 0 U2 12 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0960-7412 J9 PLANT J JI Plant J. PD MAY PY 2006 VL 46 IS 3 BP 436 EP 447 DI 10.1111/j.1365-313X.2006.02702.x PG 12 WC Plant Sciences SC Plant Sciences GA 030ZK UT WOS:000236673700007 PM 16623904 ER PT J AU Kuo, SP Bivolaru, D Williams, S Carter, CD AF Kuo, SP Bivolaru, D Williams, S Carter, CD TI A microwave-augmented plasma torch module SO PLASMA SOURCES SCIENCE & TECHNOLOGY LA English DT Article ID ATMOSPHERIC-PRESSURE; DECONTAMINATION; IGNITER AB A new plasma torch device which combines arc and microwave discharges to enhance the size and enthalpy of the plasma torch is described. A cylindrical-shaped plasma torch module is integrated into a tapered rectangular cavity to form a microwave adaptor at one end, which couples the microwave power injected into the cavity from the other end to the arc plasma generated by the torch module. A theoretical study of the microwave coupling from the cavity to the plasma torch, as the load, is presented. The numerical results indicate that the microwave power coupling efficiency exceeds 80%. Operational tests of the device indicate that the microwave power is coupled to the plasma torch and that the arc discharge power is increased. The addition of microwave energy enhances the height, volume and enthalpy of the plasma torch when the torch operates at a low airflow rate, and even when the flow speed is supersonic, a noticeable microwave effect on the plasma torch is observed. In addition, the present design allows the torch to be operated as both a fuel injector and igniter. Ignition of ethylene fuel injected through the centre of a tungsten carbide tube acting as the central electrode is demonstrated. C1 Polytech Univ, Dept Elect & Comp Engn, Brooklyn, NY 11201 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. USAF, Res Lab, Prop Directorate, Wright Patterson AFB, OH 45433 USA. RP Kuo, SP (reprint author), Polytech Univ, Dept Elect & Comp Engn, 6 Metrotech Ctr, Brooklyn, NY 11201 USA. NR 24 TC 7 Z9 7 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0963-0252 J9 PLASMA SOURCES SCI T JI Plasma Sources Sci. Technol. PD MAY PY 2006 VL 15 IS 2 BP 266 EP 275 DI 10.1088/0963-0252/15/2/012 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 053MS UT WOS:000238309800028 ER PT J AU Paulson, DB Yelda, S AF Paulson, DB Yelda, S TI Differential radial velocities and stellar parameters of nearby young stars SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID HIGH-RESOLUTION SPECTROSCOPY; PICTORIS MOVING GROUP; OPEN CLUSTER IC-2391; URSA MAJOR GROUP; SOLAR-TYPE STARS; LOW-MASS STARS; EXTRASOLAR PLANETS; CHEMICAL-COMPOSITION; KINEMATIC GROUPS; MAIN-SEQUENCE AB Radial velocity searches for substellar-mass companions have focused primarily on stars older than 1 Gyr. Increased levels of stellar activity in young stars hinders the detection of solar system analogs, and therefore until recently there has been a prejudice against inclusion of young stars in radial velocity surveys. Adaptive optics surveys of young stars have given us insight into the multiplicity of young stars, but only for massive, distant companions. Understanding the limit of the radial velocity technique, restricted to high-mass, close-orbiting planets and brown dwarfs, we began a survey of young stars of various ages. While the number of stars needed to carry out full analysis of the problems of planetary and brown dwarf population and evolution is large, the beginning of such a sample is included here. We report on 61 young stars ranging in age from the beta Pictoris association (similar to 12 Myr) to the Ursa Major association (similar to 300 Myr). This initial search resulted in no stars showing evidence of companions larger than similar to 1M(Jup)-2M(Jup) in short-period orbits at the 3 sigma level. We also present derived stellar parameters, as most have unpublished values. The chemical homogeneity of a cluster, and presumably of an association, may help to constrain true membership, so we present [Fe/H] abundances for the stars in our sample. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. RP Paulson, DB (reprint author), NASA, Goddard Space Flight Ctr, Code 693-0, Greenbelt, MD 20771 USA. EM b.paulson@gsfc.nasa.gov; syelda@umich.edu NR 52 TC 29 Z9 29 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAY PY 2006 VL 118 IS 843 BP 706 EP 715 DI 10.1086/504115 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 050WR UT WOS:000238120600006 ER PT J AU Lepri, ST Nikzad, S Jones, T Blacksberg, J Zurbuchen, TH AF Lepri, ST Nikzad, S Jones, T Blacksberg, J Zurbuchen, TH TI Response of a delta-doped charge-coupled device to low energy protons and nitrogen ions SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID CORONAL MASS EJECTIONS; SPACE WEATHER; SOLAR-WIND; SILICON; CCDS; DETECTORS; GROWTH; UV AB We present the results of a study of the response of a delta-doped charge-coupled device (CCD) exposed to ions with energies less than 10 keV. The study of ions in the solar wind, the majority having energies in the 1-5 keV range, has proven to be vital in understanding the solar atmosphere and the near Earth space environment. Delta-doped CCD technology has essentially removed the dead layer of the silicon detector. Using the delta-doped detector, we are able to detect H+ and N+ ions with energies ranging from 1 to 10 keV in the laboratory. This is a remarkable improvement in the low energy detection threshold over conventional solid-state detectors, such as those used in space sensors, one example being the solar wind ion composition spectrometer (SWICS) on the Advanced Composition Explorer spacecraft, which can only detect ions with energies greater than 30 keV because of the solid-state detector's minimum energy threshold. Because this threshold is much higher than the average energy of the solar wind ions, the SWICS instrument employs a bulky high voltage postacceleration stage that accelerates ions above the 30 keV detection threshold. This stage is massive, exposes the instrument to hazardous high voltages, and is therefore problematic both in terms of price and its impact on spacecraft resources. Adaptation of delta-doping technology in future space missions may be successful in reducing the need for heavy postacceleration stages allowing for miniaturization of space-borne ion detectors. (c) 2006 American Institute of Physics. C1 Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lepri, ST (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. RI Lepri, Susan/I-8611-2012 NR 31 TC 5 Z9 5 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 2006 VL 77 IS 5 AR 053301 DI 10.1063/1.2198829 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 048KM UT WOS:000237946000008 ER PT J AU Parravano, A Mckee, CF Hollenbach, DJ AF Parravano, A. McKee, C. F. Hollenbach, D. J. TI The stellar initial mass function and star formation in the galaxy SO REVISTA MEXICANA DE FISICA LA English DT Article DE stars : formation; stars : mass function; ISM : evolution ID LUMINOSITY FUNCTION; MILKY-WAY; CLUSTER; DEPENDENCE; EVOLUTION; DENSITY; DWARFS; COUNTS; BUDGET AB We use observational constraints on the galactic ionizing photon production, the surface mass distribution of field M dwarfs, and the mass distribution of brown dwarfs in clusters to produce an effective galactic initial mass function (IMF). We assume that the IMF can be expressed as the product of a smooth function of mass m (in units of M circle dot), psi(m), and a time dependent rate. We express the star formation rate per unit area per unit logarithmic mass interval as zeta(*)(m) equivalent to [d(2) N-* (m)]/[dA dln m] equivalent to zeta(*1) psi(m) = zeta(*1) (t) m(-Gamma) [1 - exp-(m/m(ch))(gamma+Gamma)] for (m <= m(u)), with gamma = 0.8 (the asymptotic low-mass slope inferred from the mass distribution in young clusters at sub-stellar masses), Gamma = 1.35 (the negative of the high-mass slope), m(ch) = 0.24 (producing a maximum at m(max) similar to m(ch)) and m(u) = 120. For a disk age of 11 Gyr, the average value of the star formation rate per unit logarithmic mass interval at 1 M-circle dot at the solar circle is similar or equal to 620 kpc(-2) Myr(-1), and the ratio of the present to the mean SFR is b(t(0)) = 1.085, where to is the age of the disk. C1 Univ Los Andes, Ctr Astrofis Teor, Merida 5101A, Venezuela. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Parravano, A (reprint author), Univ Los Andes, Ctr Astrofis Teor, Merida 5101A, Venezuela. NR 31 TC 1 Z9 1 U1 1 U2 1 PU SOCIEDAD MEXICANA DE FISICA PI COYOACAN PA APARTADO POSTAL 70-348, COYOACAN 04511, MEXICO SN 0035-001X J9 REV MEX FIS JI Rev. Mex. Fis. PD MAY PY 2006 VL 52 IS 3 SU S BP 1 EP 4 PG 4 WC Physics, Multidisciplinary SC Physics GA 142LO UT WOS:000244651600001 ER PT J AU Crouch, L AF Crouch, L TI The pressure's on - Students build and break composite wings with NASA mentors SO SAMPE JOURNAL LA English DT Editorial Material C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Crouch, L (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAMPE PUBLISHERS PI COVINA PA 1161 PARKVIEW DRIVE, COVINA, CA 91722 USA SN 0091-1062 J9 SAMPE J JI Sampe J. PD MAY-JUN PY 2006 VL 42 IS 3 BP 44 EP 44 PG 1 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 036RH UT WOS:000237092200017 ER PT J AU Egidi, A Caccin, B Sofia, S Heaps, W Hoegy, W Twigg, L AF Egidi, A Caccin, B Sofia, S Heaps, W Hoegy, W Twigg, L TI High-precision measurements of the solar diameter and oblateness by the Solar Disk Sextant (SDS) experiment SO SOLAR PHYSICS LA English DT Article AB We reduce and analyze, in a uniform way, all of the data obtained by the Solar Disk Sextant (SDS) experiment, concerning high-precision measurements of the solar radius and oblateness, in the bandwidth 590 - 670 nm, made onboard stratospheric balloons during a series of flights carried out in 1992, 1994, 1995, and 1996. The measured radius value appears anti-correlated with the level of solar activity, ranging from about 959.5 to 959.7 arcsec. Its variation from year to year is outside the error range, which is mostly due to a systematic diurnal behavior, particularly evident in the 1996 flight. The oblateness shows an analogous temporal behavior, ranging from about (4.3 to 10.3) x 10(-6). C1 Univ Roma Tor Vergata, Dipartimento Fis, I-00173 Rome, Italy. Yale Univ, Dept Astron, New Haven, CT 06511 USA. NASA, Goddard Space Flight Ctr, Instrument Technol Ctr, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Egidi, A (reprint author), Univ Roma Tor Vergata, Dipartimento Fis, Via E Carnevale, I-00173 Rome, Italy. EM egidi@roma2.infn.it; sofia@astro.yale.edu NR 12 TC 35 Z9 36 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD MAY PY 2006 VL 235 IS 1-2 BP 407 EP 418 DI 10.1007/s11207-006-0073-x PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 042CV UT WOS:000237505800023 ER PT J AU Silver, A Bunyk, P Kleinsasser, A Spargo, J AF Silver, A Bunyk, P Kleinsasser, A Spargo, J TI Vision for single flux quantum very large scale integrated technology SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article; Proceedings Paper CT 10th International Superconductive Electronics Conference (ISEC 2005) CY SEP 05-09, 2005 CL Noordwijkerhout, NETHERLANDS AB Single flux quantum (SFQ) electronics is extremely fast and has very low on-chip power dissipation. SFQ VLSI is an excellent candidate for high-performance computing and other applications requiring extremely high-speed signal processing. Despite this, SFQ technology has generally not been accepted for system implementation. We argue that this is due, at least in part, to the use of outdated tools to produce SFQ circuits and chips. Assuming the use of tools equivalent to those employed in the semiconductor industry, we estimate the density of Josephson junctions, circuit speed, and power dissipation that could be achieved with SFQ technology. Today, CMOS lithography is at 90-65 nm with about 20 layers. Assuming equivalent technology, aggressively increasing the current density above 100 kA cm(-2) to achieve junction speeds approximately 1000 GHz, and reducing device footprints by converting device profiles from planar to vertical, one could expect to integrate about 250 M Josephson junctions cm(-2) into SFQ digital circuits. This should enable circuit operation with clock frequencies above 200 GHz and place approximately 20 K gates within a radius of one clock period. As a result, complete microprocessors, including integrated memory registers, could be fabricated on a single chip. C1 Northrop Grumman Space Technol, Redondo Beach, CA 90278 USA. Jet Prop Lab, Pasadena, CA 91109 USA. D Wave Syst Inc, Burnaby, BC V5C 6G9, Canada. RP Silver, A (reprint author), Northrop Grumman Space Technol, 1 Space Pk, Redondo Beach, CA 90278 USA. EM Arnold.Silver@IEEE.org; pbunyk@lycos.com; alan.w.kleinsasse@jpl.nasa.gov; john.spargo@ngc.com NR 6 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD MAY PY 2006 VL 19 IS 5 BP S307 EP S311 DI 10.1088/0953-2048/19/5/S30 PG 5 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 054VE UT WOS:000238405900031 ER PT J AU Funk, S Hokkanen, B Burghaus, U Bozzolo, G Garces, JE AF Funk, S Hokkanen, B Burghaus, U Bozzolo, G Garces, JE TI CO2 adsorption on the bimetallic Zn-on-Cu(110) system SO SURFACE SCIENCE LA English DT Article DE molecular beam scattering; CO2; ZnCu surface alloy; Cu(110) support ID LOW-INDEX FACES; MOLECULAR-BEAM; METHANOL SYNTHESIS; MODEL CATALYSTS; CARBON-DIOXIDE; ZINC-OXIDE; SURFACE; ZN; DYNAMICS; CU(111) AB Adsorption probability measurements (molecular beam scattering) have been conducted to examine the adsorption dynamics (i.e. the gas-surface energy transfer processes) of CO2 adsorption on the Zn-on-Cu(110) bimetallic system. The results indicate surface alloy formation, which is in agreement with prior studies. Depositing Zn at 300 K on Cu(110), above the condensation temperature of CO2 leads to a "blocking" of CO2 adsorption sites by Zn which is incorporated in the Cu(110) surface. This apparent site blocking effect indicates a lowering of the CO, binding energy on the alloyed surface as compared with the clean Cu(110) support. The Zn coverage has been calibrated by Auger electron spectroscopy and thermal desorption spectroscopy. (c) 2006 Elsevier B.V. All rights reserved. C1 N Dakota State Univ, Dept Chem Biochem & Mol Biol, Fargo, ND 58105 USA. Ohio Aerosp Inst, Cleveland, OH 44142 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. RP Burghaus, U (reprint author), N Dakota State Univ, Dept Chem Biochem & Mol Biol, 1231 Albrecht Blv,Ladd Hall, Fargo, ND 58105 USA. EM uwe.burghaus@ndsu.edu NR 47 TC 1 Z9 1 U1 5 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 1 PY 2006 VL 600 IS 9 BP 1870 EP 1876 DI 10.1016/j.susc.2006.02.018 PG 7 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 043QU UT WOS:000237617300021 ER PT J AU Gharrett, AJ Mecklenburg, CW Seeb, LW Li, Z Matala, AP Gray, AK Heifetz, J AF Gharrett, AJ Mecklenburg, CW Seeb, LW Li, Z Matala, AP Gray, AK Heifetz, J TI Do genetically distinct rougheye rockfish sibling species differ phenotypically? SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID SEBASTES; SAMPLES AB Two cryptic species of rougheye rockfish Sebastes aleutianus, which we refer to as types I and II, have been identified independently from DNA (microsatellite and mitochondrial DNA [mtDNA]) markers and from distributions of allozyme allele frequencies. Visual differences that discriminate between these species in the field would improve their conservation and management. To delineate species, we used two microsatellite loci, mu Sma6 and mu Sma7, in conjunction with mtDNA site differences for the restriction enzymes Cfo I in the region of NADH dehydrogenase (ND) subunits 3 and 4 and Mbo I in the region of ND subunits 5 and 6. We compared meristic characters and morphological dimensions of the genetically determined species and observed that although all parameters had overlapping distributions, type II rougheye rockfish have slightly fewer and shorter gill rakers and deeper bodies. Discriminant analysis of morphological characteristics accurately delineated the species (> 94%). Rougheye rockfish have two color forms: light and dark. We examined the correlation between coloration and genotype and observed that most type II fish had the light coloration, but type I fish were either light or dark and the proportion of each color form changed geographically. We also demonstrated that frequency differences in the distributions of allozyme markers are concordant with diagnostic differences at microsatellite loci and mtDNA markers, although the allozyme markers are not diagnostic. C1 Univ Alaska Fairbanks, Juneau Ctr, Sch Fisheries & Ocean Sci, Juneau, AK 99801 USA. Point Stephens Res, Auke Bay, AK 99821 USA. Alaska Dept Fish & Game, Gene Conservat Lab, Anchorage, AK 99518 USA. Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. RP Gharrett, AJ (reprint author), Univ Alaska Fairbanks, Juneau Ctr, Sch Fisheries & Ocean Sci, 11120 Glacier Highway, Juneau, AK 99801 USA. EM ffajg@uaf.edu NR 22 TC 9 Z9 10 U1 1 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 2006 VL 135 IS 3 BP 792 EP 800 DI 10.1577/T05-136.1 PG 9 WC Fisheries SC Fisheries GA 058PJ UT WOS:000238676600020 ER PT J AU DellaCorte, C AF DellaCorte, C TI Planting the seeds for our next generation of tribologists SO TRIBOLOGY & LUBRICATION TECHNOLOGY LA English DT Editorial Material C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP DellaCorte, C (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM cdellacorte@stle.org NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 0024-7154 J9 TRIBOL LUBR TECHNOL JI Tribol. Lubr. Technol. PD MAY PY 2006 VL 62 IS 5 SI SI BP 6 EP 6 PG 1 WC Engineering, Mechanical SC Engineering GA 036MZ UT WOS:000237076500002 ER PT J AU Daulton, TL Little, BJ AF Daulton, Tyrone L. Little, Brenda J. TI Determination of chromium valence over the range Cr(0)-Cr(VI) by electron energy loss spectroscopy SO ULTRAMICROSCOPY LA English DT Article DE electron energy loss spectroscopy; chromium valence determination; L(2,3)-adsorption edges; transmission electron microscopy ID 3D TRANSITION-METALS; RAY PHOTOELECTRON-SPECTROSCOPY; EDGE FINE-STRUCTURE; LOW-FREQUENCY EPR; OXIDATION-STATES; AQUEOUS-SOLUTIONS; AB-INITIO; REDUCTION; MINERALS; SPECTRA AB Chromium is a redox active 3d transition metal with a wide range of valences (-2 to + 6) that control the geochemistry and toxicity of the element. Therefore, techniques that measure Cr valence are important bio/geochemical tools. Until now, all established methods to determine Cr valence were bulk techniques with many specific to a single, or at best, only a few oxidation state(s). We report an electron energy loss spectroscopy (EELS) technique along with an extensive suite of affined reference spectra that together, unlike other methods, can determine Cr valence (or at least constrain the possible valences) at high-spatial resolution (tens-of-nanometer scale) across a wide valence range, Cr(0)-Cr(VI). Fine structure of Cr-L(2,3) edges was parametrized by measurement of the chemical shift of the L(3) edge and the ratio of integrated intensity under the L(3) and L(2) edges. These two parameterizations were correlated to Cr valence and also the d" orbital configuration which has a large influence on L-edge fine structure. We demonstrate that it is not possible to unambiguously determine Cr valence from only one fine-structure parameterization which is the method employed to determine metal valence by nearly all previous EELS studies. Rather, multiple fine-structure parameterizations must be used together if the full range of possible Cr valences is considered. However even with two parameterizations, there are limitations. For example, distinguishing Cr(IV) from Cr(HI) is problematic and it may be difficult to distinguish low-spin Cr(H) from Cr(III). Nevertheless, when Cr is known to be divalent, low- and bigh-spin d" orbital configurations can be readily distinguished. Published by Elsevier B.V. C1 Washington Univ, Ctr Mat Innovat, St Louis, MO 63130 USA. USN, Res Lab, Stennis Space Ctr, Marine Geosci Div, Stennis Space Ctr, MS 39529 USA. USN, Res Lab, Stennis Space Ctr, Div Oceanog, Stennis Space Ctr, MS 39529 USA. RP Daulton, TL (reprint author), Washington Univ, Ctr Mat Innovat, St Louis, MO 63130 USA. EM tdaulton@physics.wustl.edu NR 97 TC 52 Z9 52 U1 1 U2 34 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 2006 VL 106 IS 7 BP 561 EP 573 DI 10.1016/j.ultramic.2006.02.005 PG 13 WC Microscopy SC Microscopy GA 055VS UT WOS:000238479300003 ER PT J AU Ominami, Y Ngo, Q Kobayashi, NP Mcilwrath, K Jarausch, K Cassell, AM Li, J Yang, CY AF Ominami, Y Ngo, Q Kobayashi, NP Mcilwrath, K Jarausch, K Cassell, AM Li, J Yang, CY TI Bottom-up sample preparation technique for interfacial characterization of vertically aligned carbon nanofibers SO ULTRAMICROSCOPY LA English DT Article DE carbon nanofiber; interconnect; sample preparation; focused ion beam (FIB); scanning transmission electron microscopy (STEM) ID FOCUSED ION-BEAM; SPECIMEN PREPARATION; GROWTH; NANOTUBES; ARRAYS; DAMAGE AB We propose a novel technique for characterizing interfacial structures in vertically aligned carbon nanofibers (CNFs) utilizing scanning transmission electron microscopy (STEM). In this technique, vertically aligned CNFs are selectively grown using plasma-enhanced chemical vapor deposition (PECVD), on a substrate comprising a narrow strip (width similar to 100 nm) formed by focused ion beam. Using STEM, we obtain images of nanostructures of CNFs having diameters as small as 10 nm, while focusing on the interfacial region near the nanofiber base. Stacked graphite sheets parallel to the substrate are observed near the base of these CNFs. (c) 2006 Elsevier B.V. All rights reserved. C1 Santa Clara Univ, Ctr Nanostruct, Santa Clara, CA 95139 USA. Hitachi High Technol Amer, Pleasanton, CA 94588 USA. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Ominami, Y (reprint author), Santa Clara Univ, Ctr Nanostruct, Santa Clara, CA 95139 USA. EM yominami@scu.edu RI Kobayashi, Nobuhiko/E-3834-2012; Li, Jun/H-7771-2013 OI Li, Jun/0000-0002-3689-8946 NR 17 TC 6 Z9 6 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 2006 VL 106 IS 7 BP 597 EP 602 DI 10.1016/j.ultramic.2006.03.001 PG 6 WC Microscopy SC Microscopy GA 055VS UT WOS:000238479300007 ER PT J AU Davies, AG Chien, S Baker, V Doggett, T Dohm, J Greeley, R Ip, F Castano, R Cichy, B Rabideau, G Tran, D Sherwood, R AF Davies, AG Chien, S Baker, V Doggett, T Dohm, J Greeley, R Ip, F Castano, R Cichy, B Rabideau, G Tran, D Sherwood, R TI Monitoring active volcanism with the autonomous sciencecraft experiment on EO-1 SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE volcanism; remote sensing; hyperspectral imaging; spacecraft autonomy; hazard monitoring ID SILICATE VOLCANISM; THERMAL EMISSION; HEAT-FLOW; IO; KILAUEA; HAWAII AB The ability to monitor and rapidly react to remote detection of volcanic activity has been greatly improved through use of the Autonomous Sciencecraft Experiment (ASE), an advanced software application installed on a spacecraft in Earth orbit. ASE is a NASA New Millennium Program experiment demonstrating science-driven autonomous command and control of a spacecraft. Flying on the Earth observing-1 (EO-1) spacecraft, ASE successfully detected thermal emission from the Mt. Erebus lava lake on 7 May 2004, having analyzed a Hyperion hyperspectral data product on board the spacecraft. EO-1 was re-tasked by ASE to obtain a follow-up observation 7 h later and sent a notification of detection of volcanic activity to the ground. The entire process was carried out autonomously. Initial acquisition to receipt on the ground of the positive detection took less than 3 h, a process that without ASE would have taken weeks. The ASE Thermal Classifier has detected several styles of effusive volcanic activity: active lava lakes, pahoehoe flow fields, open channel flows and lava domes. ASE successfully demonstrated that science-driven spacecraft operation greatly enhances science return per returned byte through the identification of the most valuable data, allowing prioritization of downlink products and the discarding of null data sets. This technology has applications on missions elsewhere in the solar system. Modified thermal classifiers can be used for detecting and monitoring active volcanism on the jovian satellite to, the neptunian moon Triton, and searching for active volcanism on Mars and icy satellites. The success of ASE is an incentive for future instrument and mission designers to consider on-board data-processing requirements (especially data storage capacity, number of processors and processor speed, and RAM) in order to take advantage of this flight-proven technology. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Tucson, AZ USA. Arizona State Univ, Tempe, AZ USA. RP Davies, AG (reprint author), CALTECH, Jet Prop Lab, Ms 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Ashley.Davies@jpl.nasa.gov RI Dohm, James/A-3831-2014 NR 39 TC 33 Z9 34 U1 3 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 30 PY 2006 VL 101 IS 4 BP 427 EP 446 DI 10.1016/j.rse.2005.08.007 PG 20 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 035NL UT WOS:000237008000001 ER PT J AU Doggett, T Greeley, R Chien, S Castano, R Cichy, B Davies, AG Rabideau, G Sherwood, R Tran, D Baker, V Dohm, J Ip, F AF Doggett, T Greeley, R Chien, S Castano, R Cichy, B Davies, AG Rabideau, G Sherwood, R Tran, D Baker, V Dohm, J Ip, F TI Autonomous detection of cryospheric change with hyperion on-board Earth Observing-1 SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE cryosphere; autonomy ID GRAIN-SIZE; SNOW COVER; WATER ICE; MARS AB On-board detection of cryospheric change in sea ice, lake ice, and snow cover is being conducted as part of the Autonomous Sciencecraft Experiment (ASE), using classifiers developed for the Hyperion hyper-spectral visible/infrared spectrometer on-board the Earth Observing-1 (EO-I) spacecraft. This classifier development was done with consideration for the novel limitations of on-board processing, data calibration, spacecraft targeting error and the spectral range of the instrument. During on-board tests, these algorithms were used to measure the extent of cloud, snow, and ice cover at a global suite of targets. Coupled with baseline imaging, uploaded thresholds were used to detect cryospheric changes such as the freeze and thaw of lake ice and the formation and break-up of sea ice. These thresholds were used to autonomously trigger follow-up observations, demonstrating the capability of the technique for future planetary missions where downlink is a constrained resource and there is high interest in data covering dynamic events, including cryospheric change. Before upload classifier performance was assessed with an overall accuracy of 83.3% as measured against manual labeling of 134 scenes. Performance was further assessed against field mapping conducted at Lake Mendota, Wisconsin as well as with labeling of scenes that were classified during on-board tests. (c) 2006 Elsevier Inc. All rights reserved. C1 Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. RP Doggett, T (reprint author), Arizona State Univ, Dept Geol Sci, POB 871404, Tempe, AZ 85287 USA. EM tcd@asu.edu RI Dohm, James/A-3831-2014 NR 37 TC 25 Z9 26 U1 1 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 30 PY 2006 VL 101 IS 4 BP 447 EP 462 DI 10.1016/j.rse.2005.11.014 PG 16 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 035NL UT WOS:000237008000002 ER PT J AU Ip, F Dohm, JM Baker, VR Doggett, T Davies, AG Castano, R Chien, S Cichy, B Greeley, R Sherwood, R Tran, D Rabideau, G AF Ip, F Dohm, JM Baker, VR Doggett, T Davies, AG Castano, R Chien, S Cichy, B Greeley, R Sherwood, R Tran, D Rabideau, G TI Flood detection and monitoring with the autonomous sciencecraft experiment onboard EO-1 SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE ASE; autonomous flood detection; EO-1; hyperion; remote sensing; flood monitoring AB In this paper, we present a new way of detecting and monitoring flooding through the Autonomous Sciencecraft Experiment (ASE) [Chien, S. T., Debban, C., Yen, R., Sherwood, R. Castano, B., & Cichy, A. G. et al. (2001). ASC Science Study Report, available from http://ASEjpl.nasa. gov], which is part of the Space Technology 6 effort under NASA's New Millennium Program. Recent autonomy experiments conducted on Earth Observing 1 (EO-1) using the ASE flight software have demonstrated the ability of several science algorithms to successfully classify key features including flood-induced changes, in hyperspectral images captured by the EO-1 Hyperion instrument. Furthermore, onboard science analysis on the classified images has been performed, and then used to modify an operational plan without interaction from the ground (Sherwood, R., Chien, S., Tran, D., Cichy, B., Castano, R., Davies, A., et al. (2004). Preliminary results of the autonomous sciencecraft experiment. In: Proceedings of the IEEE Aerospace Conference, Big Sky, MT). These algorithms are used to downlink science data only when change occurs, and to detect features of scientific interests such as flooding, volcanic eruptions, and the formation and breakup of sea ice. The purpose of this paper is to demonstrate the success of ASE and its implications on detecting, mapping, and monitoring transient processes such as flooding autonomously from space. Mapping of water inundation and its change through time is part of our focus in studying transient processes from space. In 2004, hyperspectral data were acquired from the Hyperion instrument for target areas around the world that have a high potential for flooding to develop and test floodwater classifiers. In addition, classifier thresholds were determined from both normal flows and possible flood conditions. The paper introduces the development, testing, and success of the ASE software in detecting and reacting to flooding in near real-time. ASE is now operational and flight-tested, and, thus, ready to use for space-borne reconnaissance. Successful demonstration of the floodwater classifiers includes the capture of a rare flooding event of the Australian Diamantina River during ground testing in February 2004, and the detection of flood-related changes along the Brahrnaputra River in Bangladesh and the Yukon River in Alaska during onboard testing on EO-1 in 2005. Both of these detections led to triggered responses onboard the spacecraft, which included acquiring additional Hyperion scenes. These results pave the way for future smart reconnaissance missions of transient processes on Earth and beyond. It is hoped that ASE will become a default in future missions to increase the science return by introducing spacecraft autonomy for detection and monitoring of science events, which otherwise would be discovered too late or altogether missed. (c) 2006 Elsevier Inc. All rights reserved. C1 Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. RP Ip, F (reprint author), Univ Arizona, Dept Hydrol & Water Resources, 1133 E James E Rogers Way,Harshbarger Bldg 11,Rm, Tucson, AZ 85721 USA. EM felipe@hwr.arizona.edu RI Dohm, James/A-3831-2014 NR 12 TC 38 Z9 38 U1 5 U2 15 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 30 PY 2006 VL 101 IS 4 BP 463 EP 481 DI 10.1016/j.rse.2005.12.018 PG 19 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 035NL UT WOS:000237008000003 ER PT J AU Wang, PH Fishman, J Harvey, VL Hitchman, MH AF Wang, PH Fishman, J Harvey, VL Hitchman, MH TI Southern tropical upper tropospheric zonal ozone wave-1 from SAGE II observations (1985-2002) SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CROSS-TROPOPAUSE; STRATOSPHERIC AEROSOL; CLOUD OCCURRENCE; ATLANTIC-OCEAN; INDIAN-OCEAN; WATER-VAPOR; TRACE-A; TRANSPORT; CLIMATOLOGY; MAXIMUM AB Using multiyear data (1985-2002) derived from the second Stratospheric Aerosol and Gas Experiment (SAGE II) and meteorological information (1992-2004) from the United Kingdom Meteorological Office, the present study investigates the seasonal structure of the southern tropical zonal ozone wave-1 in the upper troposphere. By using multiyear near-global ozone profile measurements from the SAGE II satellite instrument, the present study complements the analyses based on data from tropical ozonesonde networks, such as the Southern Hemisphere Additional Ozonesondes (SHADOZ), and from satellite total tropospheric ozone. The seasonal variations in the meridional ozone distributions in the high-ozone longitudinal sector (40 degrees W-60 degrees E) and the low-ozone longitudinal sector (60 degrees E-320 degrees E) are investigated in detail. The results indicate that the southern tropical zonal ozone wave-1 is a year-round feature, with the strongest amplitude occurring in austral spring and weakest in autumn. The influence of the meridional (Hadley) and equatorial (Walker) circulations on the ozone wave-1 is also examined. The analysis suggests that both Hadley and Walker circulations can contribute to the formulation of the ozone wave-1 climatological structure. C1 Sci & Technol Corp, Hampton, VA 23666 USA. NASA, Sci Directorate, Langley Res Ctr, Hampton, VA 23681 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Wang, PH (reprint author), Sci & Technol Corp, 10 Basil Sawyer Dr, Hampton, VA 23666 USA. EM p.wang@larc.nasa.gov; jack.fishman@nasa.gov; lynn.harvey@lasp.colorado.edu; matt@aos.wisc.edu NR 58 TC 5 Z9 5 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 29 PY 2006 VL 111 IS D8 AR D08305 DI 10.1029/2005JD006221 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040WS UT WOS:000237412300002 ER PT J AU Shindell, D Faluvegi, G Lacis, A Hansen, J Ruedy, R Aguilar, E AF Shindell, D Faluvegi, G Lacis, A Hansen, J Ruedy, R Aguilar, E TI Role of tropospheric ozone increases in 20th-century climate change SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTHROPOGENIC EMISSIONS; MODEL; SIMULATIONS; ATMOSPHERE; EVOLUTION; REANALYSIS; FORCINGS; NITROGEN; METHANE; SULFUR AB Human activities have increased tropospheric ozone, contributing to 20th-century warming. Using the spatial and temporal distribution of precursor emissions, we simulated tropospheric ozone from 1890 to 1990 using the NASA Goddard Institute for Space Studies (GISS) chemistry model. Archived three-dimensional ozone fields were then used in transient GISS climate model simulations. This enables more realistic evaluation of the impact of tropospheric ozone increases than prior simulations using an interpolation between preindustrial and present-day ozone. We find that tropospheric ozone contributed to the greater 20th-century warming in the Northern Hemisphere extratropics compared with the tropics and in the tropics compared with the Southern Hemisphere extratropics. Additionally, ozone increased more rapidly during the latter half of the century than the former, causing more rapid warming during that time. This is especially apparent in the tropics and is consistent with observations, which do not show similar behavior in the extratropics. Other climate forcings do not substantially accelerate warming rates in the tropics relative to other regions. This suggests that accelerated tropospheric ozone increases related to industrialization in the developing world have contributed to the accelerated tropical warming. During boreal summer, tropospheric ozone causes enhanced warming (>0.5 degrees C) over polluted northern continental regions. Finally, the Arctic climate response to tropospheric ozone increases is large during fall, winter, and spring when ozone's lifetime is comparatively long and pollution transported from midlatitudes is abundant. The model indicates that tropospheric ozone could have contributed about 0.3 degrees C annual average and about 0.4 degrees C-0.5 degrees C during winter and spring to the 20th-century Arctic warming. Pollution controls could thus substantially reduce the rapid rate of Arctic warming. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Earth Inst, New York, NY USA. Columbia Univ, Dept Earth & Environm Sci, New York, NY USA. SGT Inc, New York, NY 10025 USA. RP Shindell, D (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM dshindell@giss.nasa.gov RI Lacis, Andrew/D-4658-2012; Shindell, Drew/D-4636-2012 NR 37 TC 56 Z9 59 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 28 PY 2006 VL 111 IS D8 AR D08302 DI 10.1029/2005JD006348 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040WR UT WOS:000237412200001 ER PT J AU Liu, WT Xie, XS Tang, WQ Zlotnicki, V AF Liu, WT Xie, XS Tang, WQ Zlotnicki, V TI Spacebased observations of oceanic influence on the annual variation of South American water balance SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LA-PLATA BASIN; INTERANNUAL VARIABILITY; HYDROLOGIC-CYCLE; AMAZON; PRECIPITATION; SCATTEROMETER; ATMOSPHERE; DISCHARGE; CLIMATE; GRACE AB The mass change of South America (SA) continent measured by the Gravity Recovery and Climate Experiment (GRACE) imposes a constraint on the uncertainties in estimating the annual variation of rainfall measured by Tropical Rain Measuring Mission (TRMM) and ocean moisture influx derived from QuikSCAT data. The approximate balance of the mass change rate with the moisture influx less climatological river discharge, in agreement with the conservation principle, bolsters not only the credibility of the spacebased measurements, but supports the characterization of ocean's influence on the annual variation of continental water balance. The annual variation of rainfall is found to be in phase with the mass change rate in the Amazon and the La Plata basins, and the moisture advection across relevant segments of the Pacific and Atlantic coasts agrees with the annual cycle of rainfall in the two basins and the Andes mountains. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Liu, WT (reprint author), CALTECH, Jet Prop Lab, MS 300-323,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM liu@pacific.jpl.nasa.gov NR 21 TC 10 Z9 10 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 27 PY 2006 VL 33 IS 8 AR L08710 DI 10.1029/2006GL025683 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 040WM UT WOS:000237411600001 ER PT J AU Khazanov, GV Krivorutsky, EN Gallagher, DL AF Khazanov, GV Krivorutsky, EN Gallagher, DL TI Electrodynamic bare tether systems as a thruster for the Momentum-Exchange/Electrodynamic Reboost (MXER) project SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CYLINDRICAL LANGMUIR PROBES; MOTION-LIMITED REGIME; CURRENT COLLECTION AB The concept of electrodynamic tether propulsion has a number of attractive features and has been widely discussed for different applications. Different system designs have been proposed and compared during the last 10 years. In spite of this, the choice of proper design for any particular mission is a unique problem. Such characteristics of tether performance as system acceleration, efficiency, etc., should be calculated and compared on the basis of the known capability of a tether to collect electrical current. We discuss the choice of parameters for circular and tape tethers with regard to the Momentum-Exchange/Electrodynamic Reboost(MXER) tether project. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. Natl Space Sci & Technol Ctr, Univ Space Res Assoc, Huntsville, AL 35805 USA. RP Khazanov, GV (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. EM george.khazanov@msfc.nasa.gov NR 14 TC 1 Z9 1 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 27 PY 2006 VL 111 IS A4 AR A04309 DI 10.1029/2005JA011205 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 040XE UT WOS:000237413500001 ER PT J AU Miller, Y Chaban, GM Finlayson-Pitts, BJ Gerber, RB AF Miller, Y Chaban, GM Finlayson-Pitts, BJ Gerber, RB TI Photochemical processes induced by vibrational overtone excitations: Dynamics simulations for cis-HONO, trans-HONO, HNO3, and HNO3-H2O SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Review ID GROUND ELECTRONIC-STATE; POTENTIAL-ENERGY SURFACES; PROTON-TRANSFER REACTIONS; PEROXYNITROUS ACID HOONO; SELF-CONSISTENT-FIELD; NITRIC-ACID; AB-INITIO; PHOTODISSOCIATION DYNAMICS; NITROUS-ACID; GAS-PHASE AB Photochemical processes in HNO3, HNO3-H2O, and cis- and trans-HONO following overtone excitation of the OH stretching mode are studied by classical trajectory simulations. Initial conditions for the trajectories are sampled according to the initially prepared vibrational wave function. Semiempirical potential energy surfaces are used in "on-the-fly" simulations. Several tests indicate at least semiquantitative validity of the potential surfaces employed. A number of interesting new processes and intermediate species are found. The main results include the following: (1) In excitation of HNO3 to the fifth and sixth OH-stretch overtone, hopping of the H atom between the oxygen atoms is found to take place in nearly all trajectories, and can persist for many picoseconds. H-atom hopping events have a higher yield and a faster time scale than the photodissociation of HNO3 into OH and NO2. (2) A fraction of the trajectories for HNO3 show isomerization into HOONO, which in a few cases dissociates into HOO and NO. (3) For high overtone excitation of HONO. isomerization into the weakly bound species HOON is seen in all trajectories, in part of the events as an intermediate step on the way to dissociation into OH + NO. This process has not been reported previously. Well-established processes for HONO, including cis-trans isomerization and H hopping are also observed. (4) Only low overtone levels of HNO3-H2O have sufficiently long liftimes to be spectrocopically relevant. Excitation of these CH stretching overtones is found to result in the dissociation of the cluster H hopping, or dissociation of HNO3 does not take place. The results demonstrate the richness of processes induced by overtone excitation of HNOx species, with evidence for new phenomena. Possible relevance of the results to atmospheric processes is discussed. C1 Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. Hebrew Univ Jerusalem, Fritz Haber Res Ctr, IL-91904 Jerusalem, Israel. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. RP Gerber, RB (reprint author), Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. EM benny@fh.huji.ac.il NR 120 TC 41 Z9 42 U1 6 U2 36 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD APR 27 PY 2006 VL 110 IS 16 BP 5342 EP 5354 DI 10.1021/jp0559940 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 037QZ UT WOS:000237163300014 PM 16623461 ER PT J AU Bertone, G Kusenko, A Palomares-Ruiz, S Pascoli, S Semikoz, D AF Bertone, G Kusenko, A Palomares-Ruiz, S Pascoli, S Semikoz, D TI Gamma-ray bursts and the origin of galactic positrons SO PHYSICS LETTERS B LA English DT Article ID ANNIHILATION RADIATION; CENTER REGION; CENTER DIRECTION; LINE EMISSION; BLACK-HOLES; GALAXIES; SPECTRUM; MODEL AB A recent observation of the 511 keV electron-positron annihilation line from the Galactic bulge has prompted a debate on the origin of the galactic positrons responsible for this emission. Assuming equilibrium between annihilation and injection of positrons in the Galaxy, we investigate the possibility that positrons were produced by past gamma-ray bursts (GRBs). We compare the positron annihilation rate inferred by the observed 511 keV line, with the predicted injection rate due to e(+)e(-) pairs leaking out of individual GRBs and those pair produced by GRB photons in the dense molecular clouds at the Galactic center. We conclude that the proposed scenario is marginally consistent with observations, and can reproduce the observed normalization of the annihilation line only for higher-than-average values of the GRB rate in the Galaxy and/or of the molecular clouds optical depth for pair production. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Fermilab Theoret Astrophys Grp, Batavia, IL 60510 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. RP NASA, Fermilab Theoret Astrophys Grp, Batavia, IL 60510 USA. EM gianfranco.bertone@pd.infn.it RI Palomares-Ruiz, Sergio/K-8048-2014 OI Palomares-Ruiz, Sergio/0000-0001-9049-2288 NR 61 TC 33 Z9 33 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD APR 27 PY 2006 VL 636 IS 1 BP 20 EP 24 DI 10.1016/j.physletb.2006.03.022 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 038EH UT WOS:000237201100004 ER PT J AU Ivosevic, M Knight, R Kalidindi, SR Palmese, GR Sutter, JK AF Ivosevic, M Knight, R Kalidindi, SR Palmese, GR Sutter, JK TI Solid particle erosion resistance of thermally sprayed functionally graded coatings for polymer matrix composites SO SURFACE & COATINGS TECHNOLOGY LA English DT Article DE erosion resistance; functionally graded coatings; composites; thermal spray AB Thermally sprayed functionally graded coatings based on a polyimide matrix filled with varying volume fractions of WC-Co have been investigated to improve the erosion and oxidation resistance of polymer matrix composites. A study of the coatings' effectiveness as erosion barriers was accomplished through a statistical analysis of the results of solid particle erosion testing of coated and uncoated polymer matrix composite (PMC) samples using a design of experiments (DoE) approach. Two coating systems and a control sample were evaluated in a randomized test matrix. The coatings were tested at room temperature and 250 degrees C, using an alumina erodent impacting the coatings at a speed of 100 m/s at angles of 20 degrees and 90 degrees. In general, as the angle of incidence of the eroding material increased from 20 degrees to 90 degrees the volume loss increased. Erosion Volume loss at 250 degrees C was approximately twice that at room temperature. (c) 2005 Elsevier B.V. All rights reserved. C1 Drexel Univ, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Drexel Univ, Dept Chem Engn, Philadelphia, PA 19104 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Knight, R (reprint author), Drexel Univ, Dept Mat Sci & Engn, 3141 Chestnut St, Philadelphia, PA 19104 USA. EM knightr@coe.drexel.edu RI Kalidindi, Surya/A-1024-2007; OI Kalidindi, Surya/0000-0001-6909-7507 NR 15 TC 21 Z9 21 U1 0 U2 10 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD APR 27 PY 2006 VL 200 IS 16-17 BP 5145 EP 5151 DI 10.1016/j.surfcoat.2005.05.038 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 029UQ UT WOS:000236590300065 ER PT J AU Dessler, AE Palm, SP Hart, WD Spinhirne, JD AF Dessler, AE Palm, SP Hart, WD Spinhirne, JD TI Tropopause-level thin cirrus coverage revealed by ICESat/Geoscience Laser Altimeter System SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TROPICAL TROPOPAUSE; RADIATIVE IMPACTS; WATER-VAPOR; STRATOSPHERE; DEHYDRATION; CONVECTION; CLOUDS; LAYER; TRANSPORT; VARIABILITY AB We analyze the distribution of thin (optical depth < 0.40) cirrus in the tropics at potential temperatures of 360, 370, 377.5, and 400 K, which are levels that bracket the tropical tropopause. The observations were obtained between 29 September and 17 November 2003 by the Geoscience Laser Altimeter System (GLAS), carried on board the Ice, Cloud, and land Elevation Satellite (ICESat). The GLAS data show that these thin, near-tropopause cirrus (TNTC) occur over broad regions of the latitude range 20 degrees S to 30 degrees N, with distinct maxima collocated with regions of intense convection, and that TNTC occurrence frequency decreases strongly with increasing altitude. At 377.5 K, approximately the level of the tropical tropopause, TNTC frequency over convection is two to six times larger than in the so-called "cold pool,'' the climatological temperature minimum located over the equatorial western Pacific where it has been suggested that dehydration of air entering the stratosphere is occurring. Comparisons between assimilated temperatures, outgoing longwave radiation (a proxy for deep convection), and TNTC frequency show that TNTC can be found where assimilated temperatures are low and deep convection is occurring. We find that assimilated temperatures, by themselves, are incomplete predictors of TNTC locations. C1 Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Texas A&M Univ, Dept Atmospher Sci, TAMU 3150, College Stn, TX 77843 USA. EM adessler@tamu.edu RI Dessler, Andrew/G-8852-2012 OI Dessler, Andrew/0000-0003-3939-4820 NR 48 TC 40 Z9 40 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 26 PY 2006 VL 111 IS D8 AR D08203 DI 10.1029/2005JD006586 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040WQ UT WOS:000237412100005 ER PT J AU Fetzer, EJ Lambrigtsen, BH Eldering, A Aumann, HH Chahine, MT AF Fetzer, EJ Lambrigtsen, BH Eldering, A Aumann, HH Chahine, MT TI Biases in total precipitable water vapor climatologies from Atmospheric Infrared Sounder and Advanced Microwave Scanning Radiometer SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID VERTICAL-DISTRIBUTION; SATELLITE; HUMIDITY; MISSION; CLOUDS; OCEAN; AIRS; AIRS/AMSU/HSB; TEMPERATURE; VARIABILITY AB We examine differences in total precipitable water vapor (PWV) from the Atmospheric Infrared Sounder (AIRS) and the Advanced Microwave Scanning Radiometer (AMSR-E) experiments sharing the Aqua spacecraft platform. Both systems provide estimates of PWV over water surfaces. We compare AIRS and AMSR-E PWV to constrain AIRS retrieval uncertainties as functions of AIRS retrieved infrared cloud fraction. PWV differences between the two instruments vary only weakly with infrared cloud fraction up to about 70%. Maps of AIRS-AMSR-E PWV differences vary with location and season. Observational biases, when both instruments observe identical scenes, are generally less than 5%. Exceptions are in cold air outbreaks where AIRS is biased moist by 10-20% or 10-60% (depending on retrieval processing) and at high latitudes in winter where AIRS is dry by 5-10%. Sampling biases, from different sampling characteristics of AIRS and AMSR-E, vary in sign and magnitude. AIRS sampling is dry by up to 30% in most high-latitude regions but moist by 5-15% in subtropical stratus cloud belts. Over the northwest Pacific, AIRS samples conditions more moist than AMSR-E by a much as 60%. We hypothesize that both wet and dry sampling biases are due to the effects of clouds on the AIRS retrieval methodology. The sign and magnitude of these biases depend upon the types of cloud present and on the relationship between clouds and PWV. These results for PWV imply that climatologies of height-resolved water vapor from AIRS must take into consideration local meteorological processes affecting AIRS sampling. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Fetzer, EJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM eric.j.fetzer@jpl.nasa.gov NR 41 TC 32 Z9 32 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 26 PY 2006 VL 111 IS D9 AR D09S16 DI 10.1029/2005JD006598 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040WT UT WOS:000237412400001 ER PT J AU Stevenson, DS Dentener, FJ Schultz, MG Ellingsen, K van Noije, TPC Wild, O Zeng, G Amann, M Atherton, CS Bell, N Bergmann, DJ Bey, I Butler, T Cofala, J Collins, WJ Derwent, RG Doherty, RM Drevet, J Eskes, HJ Fiore, AM Gauss, M Hauglustaine, DA Horowitz, LW Isaksen, ISA Krol, MC Lamarque, JF Lawrence, MG Montanaro, V Muller, JF Pitari, G Prather, MJ Pyle, JA Rast, S Rodriguez, JM Sanderson, MG Savage, NH Shindell, DT Strahan, SE Sudo, K Szopa, S AF Stevenson, DS Dentener, FJ Schultz, MG Ellingsen, K van Noije, TPC Wild, O Zeng, G Amann, M Atherton, CS Bell, N Bergmann, DJ Bey, I Butler, T Cofala, J Collins, WJ Derwent, RG Doherty, RM Drevet, J Eskes, HJ Fiore, AM Gauss, M Hauglustaine, DA Horowitz, LW Isaksen, ISA Krol, MC Lamarque, JF Lawrence, MG Montanaro, V Muller, JF Pitari, G Prather, MJ Pyle, JA Rast, S Rodriguez, JM Sanderson, MG Savage, NH Shindell, DT Strahan, SE Sudo, K Szopa, S TI Multimodel ensemble simulations of present-day and near-future tropospheric ozone SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID CHEMISTRY TRANSPORT MODELS; GENERAL-CIRCULATION MODEL; BIOGENIC NOX EMISSIONS; GLOBAL CHEMICAL-MODEL; AIRCRAFT MOZAIC DATA; CLIMATE-CHANGE; NONMETHANE HYDROCARBONS; METHANE EMISSIONS; SURFACE OZONE; ATMOSPHERIC CHEMISTRY AB Global tropospheric ozone distributions, budgets, and radiative forcings from an ensemble of 26 state-of-the-art atmospheric chemistry models have been intercompared and synthesized as part of a wider study into both the air quality and climate roles of ozone. Results from three 2030 emissions scenarios, broadly representing "optimistic,'' "likely,'' and "pessimistic'' options, are compared to a base year 2000 simulation. This base case realistically represents the current global distribution of tropospheric ozone. A further set of simulations considers the influence of climate change over the same time period by forcing the central emissions scenario with a surface warming of around 0.7K. The use of a large multimodel ensemble allows us to identify key areas of uncertainty and improves the robustness of the results. Ensemble mean changes in tropospheric ozone burden between 2000 and 2030 for the 3 scenarios range from a 5% decrease, through a 6% increase, to a 15% increase. The intermodel uncertainty (+/-1 standard deviation) associated with these values is about +/-25%. Model outliers have no significant influence on the ensemble mean results. Combining ozone and methane changes, the three scenarios produce radiative forcings of -50, 180, and 300 mW m(-2), compared to a CO2 forcing over the same time period of 800-1100 mW m(-2). These values indicate the importance of air pollution emissions in short-to medium-term climate forcing and the potential for stringent/lax control measures to improve/worsen future climate forcing. The model sensitivity of ozone to imposed climate change varies between models but modulates zonal mean mixing ratios by +/-5 ppbv via a variety of feedback mechanisms, in particular those involving water vapor and stratosphere-troposphere exchange. This level of climate change also reduces the methane lifetime by around 4%. The ensemble mean year 2000 tropospheric ozone budget indicates chemical production, chemical destruction, dry deposition and stratospheric input fluxes of 5100, 4650, 1000, and 550 Tg(O-3) yr(-1), respectively. These values are significantly different to the mean budget documented by the Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report (TAR). The mean ozone burden (340 Tg(O-3)) is 10% larger than the IPCC TAR estimate, while the mean ozone lifetime (22 days) is 10% shorter. Results from individual models show a correlation between ozone burden and lifetime, and each model's ozone burden and lifetime respond in similar ways across the emissions scenarios. The response to climate change is much less consistent. Models show more variability in the tropics compared to midlatitudes. Some of the most uncertain areas of the models include treatments of deep tropical convection, including lightning NOx production; isoprene emissions from vegetation and isoprene's degradation chemistry; stratosphere-troposphere exchange; biomass burning; and water vapor concentrations. C1 Univ Edinburgh, Sch Geosci, Edinburgh EH9 3J9, Midlothian, Scotland. Joint Res Ctr, Inst Environm & Sustainabil, I-21020 Ispra, Italy. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. Univ Oslo, Dept Geosci, N-0316 Oslo, Norway. Royal Netherlands Meteorol Inst, De Bilt, Netherlands. Japan Marine Sci & Technol Ctr, Frontier Res Ctr Global Change, Kanazawa Ku, Yokohama, Kanagawa 2360001, Japan. Univ Cambridge, Ctr Atmospher Sci, Cambridge CB2 1EW, England. Int Inst Appl Syst Anal, A-2361 Laxenburg, Austria. Lawrence Livermore Natl Lab, Div Atmospher Sci, Livermore, CA 94550 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Ecole Polytech Fed Lausanne, CH-1015 Lausanne, Switzerland. Max Planck Inst Chem, D-55128 Mainz, Germany. Hadley Ctr Climate Predict & Res, Met Off, Exeter EX1 3PB, Devon, England. rdscientific, Newbury RG14 6LH, Berks, England. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08540 USA. Lab Sci Climat & Environm, F-91191 Gif Sur Yvette, France. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. Univ Aquila, Dipartimento Fis, I-67010 Laquila, Italy. Belgian Inst Space Aeron, B-1180 Brussels, Belgium. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. RP Univ Edinburgh, Sch Geosci, Crew Bldg,Kings Bldg, Edinburgh EH9 3J9, Midlothian, Scotland. EM dstevens@staffmail.ed.ac.uk RI Rodriguez, Jose/G-3751-2013; Krol, Maarten/E-3414-2013; Wild, Oliver/A-4909-2009; Collins, William/A-5895-2010; Szopa, Sophie/F-8984-2010; Krol, Maarten/B-3597-2010; Bergmann, Daniel/F-9801-2011; Butler, Tim/G-1139-2011; Stevenson, David/C-8089-2012; Shindell, Drew/D-4636-2012; Strahan, Susan/H-1965-2012; Magana, Felipe/B-6966-2013; Horowitz, Larry/D-8048-2014; Lamarque, Jean-Francois/L-2313-2014; Unger, Nadine/M-9360-2015; Pitari, Giovanni/O-7458-2016; Schultz, Martin/I-9512-2012; OI Rodriguez, Jose/0000-0002-1902-4649; Wild, Oliver/0000-0002-6227-7035; Collins, William/0000-0002-7419-0850; Szopa, Sophie/0000-0002-8641-1737; Bergmann, Daniel/0000-0003-4357-6301; Stevenson, David/0000-0002-4745-5673; Horowitz, Larry/0000-0002-5886-3314; Lamarque, Jean-Francois/0000-0002-4225-5074; Pitari, Giovanni/0000-0001-7051-9578; Schultz, Martin/0000-0003-3455-774X; Savage, Nicholas/0000-0001-9391-5100; Derwent, Richard/0000-0003-4498-645X NR 155 TC 402 Z9 405 U1 12 U2 109 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 26 PY 2006 VL 111 IS D8 AR D08301 DI 10.1029/2005JD006338 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040WQ UT WOS:000237412100003 ER PT J AU Quinn, RC Zent, AP Garry, JRC Ringrose, TJ Towner, MC Grunthaner, FJ AF Quinn, RC Zent, AP Garry, JRC Ringrose, TJ Towner, MC Grunthaner, FJ TI An atmospheric oxidation monitor based on in situ thin-film deposition SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE oxidation sensor; hydrogen peroxide; chemiresistor; mars ID MARTIAN ATMOSPHERE; MARS; CHEMISTRY AB We describe an atmospheric oxidation sensor developed and delivered as part of the European Space Agency (ESA) Beagle 2 (B2) Mars Lander Environmental Sensor Suite (ESS). The sensor monitors atmospheric oxidation rates by measuring resistance changes in a thin-silver (Ag) film deposited in situ onto a sapphire substrate while on the surface of Mars. Potential terrestrial applications of this sensing approach include long-term monitoring of oxidative contaminants in low-oxygen systems including process gases and environmental chambers. The sensor response to ppb levels of hydrogen peroxide (H2O2) vapor in carbon dioxide (CO2) is demonstrated. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. Leiden Univ, Astrobiol Grp, Leiden Inst Chem, NL-2300 RA Leiden, Netherlands. Open Univ, Planetary & Space Sci Res Inst, Milton Keynes MK7 6AA, Bucks, England. NASA, Jet Prop Lab, Situ Explorat Technol Grp, Pasadena, CA 91109 USA. RP Quinn, RC (reprint author), NASA, Ames Res Ctr, SETI Inst, Mail Stop 239-12, Moffett Field, CA 94035 USA. EM rquinn@mail.arc.nasa.gov NR 8 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD APR 26 PY 2006 VL 114 IS 2 BP 841 EP 848 DI 10.1016/j.snb.2005.08.003 PG 8 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 030RI UT WOS:000236651600040 ER PT J AU Salem, JA Singh, A AF Salem, JA Singh, A TI Polynomial expressions for estimating elastic constants from the resonance of circular plates SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE dynamic modulus of elasticity; resonance; young's modulus; Poisson's ratio; ceramics; metals; standards; circular plates; interpolation; resonant vibration AB Two approaches were taken to make convenient spread sheet calculations of elastic constants from resonance data and the Tables in ASTM C 1259 and E1876: (1) polynomials were fit to the tables; (2) an automated spread sheet interpolation routine was generated. To compare the approaches, the resonant frequencies of circular plates made of glass, hardened maraging steel, alpha silicon carbide, silicon nitride, tungsten carbide, tape cast NiO-YSZ, and zinc selenide were measured. The elastic constants, as calculated via the polynomials and linear interpolation of the tabular data in ASTM C1259 and E1876, were found comparable for engineering purposes, with the differences typically being less than 0.5%. Calculation of additional v values at t/R between 0 and 0.2 would allow better curve fits. This is not necessary for common engineering purposes, however, it might benefit the testing of emerging thin structures such as fuel cell electrolytes, gas conversion membranes, and coatings when Poisson's ratio is less than 0.15 and high precision is needed. (c) 2006 Published by Elsevier B.V. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Brookpark, OH 44142 USA. RP Salem, JA (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM jonathan.a.salem@grc.nasa.gov NR 10 TC 6 Z9 6 U1 0 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 25 PY 2006 VL 422 IS 1-2 BP 292 EP 297 DI 10.1016/j.msea.2006.02.023 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 048LE UT WOS:000237947800033 ER PT J AU Horiuchi, S Meier, DL Preston, RA Tingay, SJ AF Horiuchi, Shinji Meier, David L. Preston, Robert A. Tingay, Steven J. TI Ten milliparsec-scale structure of the nucleus region in Centaurus A SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN LA English DT Article DE galaxies : active; galaxies : individual (Centaurus A); techniques : interferometric ID BLACK-HOLE; RADIO; JET; EVOLUTION; NGC-5128 AB We present the results of a VLB1 Space Observatory Programme (VSOP) observation of the subparsec structure in Cen A at 4.9 GHz. The observation produced an image of the subparsecjet components with a resolution of three-times better than images from previous VLB1 monitoring campaigns at 8.4 GHz, and twice better than the previous 22 GHz studies. Owing to its proximity, our Cen A space-VLBI image is one of the highest spatial-resolution images of an AGN ever made - 0.01 pc per beam - comparable only to the recent 43 GHz VLBI images of M 87. The elongated core region is resolved into several components of over 10 milliarcsec long (0.2 pc), including a compact component of brightness temperature 2.2x 10(10)K. A counterjet was detected: if we assume jet-counterjet symmetry, a relatively slow jet speed, and a large viewing angle, as derived from previous observations. the image allows us to investigate the distribution of ionized gas around the core, which is opaque at this frequency due to free-free absorption. We also anal zed the jet geometry in terms of collimation. Assuming the strongest component to be the core, the jet opening angle at similar to 5000rs from the core is estimated to be similar to 12 degrees, with the collimation of the jet to similar to 3 degrees continuing out to similar to 20000r(S). This result is consistent with previous studies of the jet in M 87, which favor MHD disk outflow models. Future space VLB1 observations at higher frequencies will probably be able to image C, the collimation region, within 1000r(S) of the center of Cen A, together with the accretion disk itself. C1 Swinburne Univ Technol, Ctr Astrophys & Supercomp, Hawthorn, Vic 3122, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Horiuchi, S (reprint author), Swinburne Univ Technol, Ctr Astrophys & Supercomp, Mail No H39,POB 218, Hawthorn, Vic 3122, Australia. EM shorhtchi@swin.edu.au RI Tingay, Steven/B-5271-2013 NR 18 TC 39 Z9 40 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0004-6264 EI 2053-051X J9 PUBL ASTRON SOC JPN JI Publ. Astron. Soc. Jpn. PD APR 25 PY 2006 VL 58 IS 2 BP 211 EP 216 DI 10.1093/pasj/58.2.211 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 041XZ UT WOS:000237491800001 ER PT J AU Pumphrey, HC Jimenez, CJ Waters, JW AF Pumphrey, HC Jimenez, CJ Waters, JW TI Measurement of HCN in the middle atmosphere by EOS MLS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HYDROGEN-CYANIDE HCN; CH3CN; SINKS; OCEAN AB The EOS MLS instrument on NASA's Aura satellite has made the first continuous global measurements of HCN in the middle atmosphere. The measurements are in broad agreement with most earlier measurements, showing HCN to be a long-lived tracer with sources in the troposphere and sinks in the middle atmosphere. There is no evidence in the data for a proposed mesospheric source of HCN. C1 Univ Edinburgh, Sch Geosci, Inst Atmospher & Environm Sci, Edinburgh EH9 3JN, Midlothian, Scotland. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pumphrey, HC (reprint author), Univ Edinburgh, Sch Geosci, Inst Atmospher & Environm Sci, Edinburgh EH9 3JN, Midlothian, Scotland. EM h.c.pumphrey@ed.ac.uk NR 12 TC 10 Z9 10 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 22 PY 2006 VL 33 IS 8 AR L08804 DI 10.1029/2005GL025656 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039LX UT WOS:000237308300005 ER PT J AU Uritsky, VM Klimas, AJ Vassiliadis, D AF Uritsky, VM Klimas, AJ Vassiliadis, D TI Critical finite-size scaling of energy and lifetime probability distributions of auroral emissions SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SELF-ORGANIZED CRITICALITY; DYNAMIC MAGNETOSPHERE; AVALANCHING SYSTEM; SPACE; BEHAVIOR; PLASMAS; MODELS; SHEET AB Based on statistical study of approximately 15,500 ultraviolet images of auroral emission regions provided by the UVI experiment on the POLAR spacecraft, we show that energy and duration probability distributions of particle precipitation events obey finite-size scaling relations indicative of a self-organized critical (SOC) dynamical state. The revealed relations are invariant with respect to significant changes in the spatial scale of the emission areas, and involve a set of mutually consistent critical exponents providing a quantitative basis for future theoretical studies of multiscale magnetospheric fluctuations. The reported statistical results highlight the importance of cross-scale coupling in the development of nighttime geomagnetic disturbances and suggest that various manifestations of substorm activity associated with localized magnetic reconnections in the magnetotail ( small to large scale substorms, pseudo-breakups, BBFs and other types of short-term localized excitations) can be coordinated on the global scale by universal dynamical principle represented by scale-free avalanching in numerical SOC models. C1 St Petersburg State Univ, Inst Phys, St Petersburg, Russia. NASA, Sarissa Technol, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Uritsky, VM (reprint author), Univ Calgary, Phys Astron Dept 2, Complex Sci Grp, Calgary, AB, Canada. EM vuritsky@phas.ucalgary.ca; alex.klimas@nasa.gov; vassi@electra.gsfc.nasa.gov NR 21 TC 19 Z9 19 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 22 PY 2006 VL 33 IS 8 AR L08102 DI 10.1029/2005GL025330 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039LX UT WOS:000237308300002 ER PT J AU Ricca, A Bauschlicher, CW AF Ricca, A Bauschlicher, CW TI The adsorption of NO2 on (9,0) and (10,0) carbon nanotubes SO CHEMICAL PHYSICS LA English DT Article DE carbon nanotubes; sensors; DFT; NO2 ID COUPLED-CLUSTER THEORY; CORRELATION-ENERGY; ELECTRON CORRELATION; AB-INITIO; DENSITY; GAS; APPROXIMATION; EXCHANGE; CHEMISORPTION; MOLECULES AB On the basis of calculations, the physisorption of NO2, N2O4, and NO3 are estimated to be 5 +/- 2, 12 +/- 3, and 9 +/- 3 kcal/mol, respectively. The chemisorption energy of two NO2 molecules on (9,0) and (10,0) tubes is computed to be 16 and 8 kcal/mol, respectively, while the chemisorption of two NO3 molecules is much more exothermic. The implication of these binding energies on the sensor mechanism of carbon nanotubes is discussed. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Bauschlicher, CW (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Mail Stop 230-3, Moffett Field, CA 94035 USA. EM ricca@pegasus.arc.nasa.gov; charles.w.bauschlicher@nasa.gov NR 31 TC 33 Z9 34 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD APR 21 PY 2006 VL 323 IS 2-3 BP 511 EP 518 DI 10.1016/j.chemphys.2005.10.019 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 040KT UT WOS:000237378100039 ER PT J AU Abbott, B Abbott, R Adhikari, R Agresti, J Ajith, P Allen, B Allen, J Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Aulbert, C Babak, S Balasubramanian, R Ballmer, S Bantilan, H Barish, BC Barker, C Barker, D Barton, MA Bayer, K Belczynski, K Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Buonanno, A Busby, D Butler, WE Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cao, J Cardenas, L Carter, K Casey, MM Charlton, P Chatterji, S Chen, Y Chin, D Christensen, N Cokelaer, T Colacino, CN Coldwell, R Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G DeBra, D Dergachev, V Desai, S DeSalvo, R Dhurandar, S Diaz, M Di Credico, A Drever, RWP Dupuis, RJ Ehrens, P Etzel, T Evans, M Evans, T Fairhurst, S Finn, LS Franzen, KY Frey, RE Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Gholami, I Giaime, JA Goda, K Goggin, L Gonzalez, G Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, R Hamilton, WO Hanna, C Hanson, J Hardham, C Harry, G Heefner, J Heng, IS Hewitson, M Hindman, N Hoang, P Hough, J Hua, W Ito, M Itoh, Y Ivanov, A Johnson, B Johnson, WW Jones, DI Jones, G Jones, L Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Khan, A Kim, C King, P Klimenko, S Koranda, S Kozak, D Krishnan, B Landry, M Lantz, B Lazzarini, A Lei, M Leonor, I Libbrecht, K Lindquist, P Liu, S Lormand, M Lubinski, M Luck, H Luna, M Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Malec, M Mandic, V Marka, S Maros, E Mason, K Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Melissinos, A Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Myers, E Myers, J Nash, T Nocera, F Noel, JS O'Reilly, B O'Shaughnessy, R Ottaway, DJ Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswariah, C Pedraza, M Penn, S Pitkin, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rawlins, K Ray-Majumder, S Re, V Regimbau, T Reitze, DH Riesen, R Riles, K Rivera, B Robertson, DI Robertson, NA Robinson, C Roddy, S Rodriguez, A Rollins, J Romano, JD Romie, J Rowan, S Rudiger, A Ruet, L Russell, P Ryan, K Sandberg, V Sanders, GH Sannibale, V Sarin, P Sathyaprakash, BS Saulson, PR Savage, R Sazonov, A Schilling, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Sellers, D Sengupta, AS Shawhan, P Shoemaker, DH Sibley, A Siemens, X Sigg, D Sintes, AM Smith, J Smith, MR Spjeld, O Strain, KA Strom, DM Stuver, A Summerscales, T Sung, M Sutton, PJ Tanner, DB Tarallo, M Taylor, R Thorne, KA Thorne, KS Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Ward, H Ward, R Watts, K Webber, D Weiland, U Weinstein, A Weiss, R Wen, S Wette, K Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Willke, B Wilson, A Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Yakushin, I Yamamoto, H Yoshida, S Zanolin, M Zhang, L Zotov, N Zucker, M Zweizig, J AF Abbott, B. Abbott, R. Adhikari, R. Agresti, J. Ajith, P. Allen, B. Allen, J. Amin, R. Anderson, S. B. Anderson, W. G. Araya, M. Armandula, H. Ashley, M. Aulbert, C. Babak, S. Balasubramanian, R. Ballmer, S. Bantilan, H. Barish, B. C. Barker, C. Barker, D. Barton, M. A. Bayer, K. Belczynski, K. Betzwieser, J. Bhawal, B. Bilenko, I. A. Billingsley, G. Black, E. Blackburn, K. Blackburn, L. Bland, B. Bogue, L. Bork, R. Bose, S. Brady, P. R. Braginsky, V. B. Brau, J. E. Brown, D. A. Buonanno, A. Busby, D. Butler, W. E. Cadonati, L. Cagnoli, G. Camp, J. B. Cannizzo, J. Cannon, K. Cao, J. Cardenas, L. Carter, K. Casey, M. M. Charlton, P. Chatterji, S. Chen, Y. Chin, D. Christensen, N. Cokelaer, T. Colacino, C. N. Coldwell, R. Cook, D. Corbitt, T. Coyne, D. Creighton, J. D. E. Creighton, T. D. Dalrymple, J. D'Ambrosio, E. Danzmann, K. Davies, G. DeBra, D. Dergachev, V. Desai, S. DeSalvo, R. Dhurandar, S. Diaz, M. Di Credico, A. Drever, R. W. P. Dupuis, R. J. Ehrens, P. Etzel, T. Evans, M. Evans, T. Fairhurst, S. Finn, L. S. Franzen, K. Y. Frey, R. E. Fritschel, P. Frolov, V. V. Fyffe, M. Ganezer, K. S. Garofoli, J. Gholami, I. Giaime, J. A. Goda, K. Goggin, L. Gonzalez, G. Gray, C. Gretarsson, A. M. Grimmett, D. Grote, H. Grunewald, S. Guenther, M. Gustafson, R. Hamilton, W. O. Hanna, C. Hanson, J. Hardham, C. Harry, G. Heefner, J. Heng, I. S. Hewitson, M. Hindman, N. Hoang, P. Hough, J. Hua, W. Ito, M. Itoh, Y. Ivanov, A. Johnson, B. Johnson, W. W. Jones, D. I. Jones, G. Jones, L. Kalogera, V. Katsavounidis, E. Kawabe, K. Kawamura, S. Kells, W. Khan, A. Kim, C. King, P. Klimenko, S. Koranda, S. Kozak, D. Krishnan, B. Landry, M. Lantz, B. Lazzarini, A. Lei, M. Leonor, I. Libbrecht, K. Lindquist, P. Liu, S. Lormand, M. Lubinski, M. Lueck, H. Luna, M. Machenschalk, B. MacInnis, M. Mageswaran, M. Mailand, K. Malec, M. Mandic, V. Marka, S. Maros, E. Mason, K. Matone, L. Mavalvala, N. McCarthy, R. McClelland, D. E. McHugh, M. McNabb, J. W. C. Melissinos, A. Mendell, G. Mercer, R. A. Meshkov, S. Messaritaki, E. Messenger, C. Mikhailov, E. Mitra, S. Mitrofanov, V. P. Mitselmakher, G. Mittleman, R. Miyakawa, O. Mohanty, S. Moreno, G. Mossavi, K. Mueller, G. Mukherjee, S. Myers, E. Myers, J. Nash, T. Nocera, F. Noel, J. S. O'Reilly, B. O'Shaughnessy, R. Ottaway, D. J. Overmier, H. Owen, B. J. Pan, Y. Papa, M. A. Parameshwaraiah, V. Parameswariah, C. Pedraza, M. Penn, S. Pitkin, M. Prix, R. Quetschke, V. Raab, F. Radkins, H. Rahkola, R. Rakhmanov, M. Rawlins, K. Ray-Majumder, S. Re, V. Regimbau, T. Reitze, D. H. Riesen, R. Riles, K. Rivera, B. Robertson, D. I. Robertson, N. A. Robinson, C. Roddy, S. Rodriguez, A. Rollins, J. Romano, J. D. Romie, J. Rowan, S. Ruediger, A. Ruet, L. Russell, P. Ryan, K. Sandberg, V. Sanders, G. H. Sannibale, V. Sarin, P. Sathyaprakash, B. S. Saulson, P. R. Savage, R. Sazonov, A. Schilling, R. Schofield, R. Schutz, B. F. Schwinberg, P. Scott, S. M. Seader, S. E. Searle, A. C. Sears, B. Sellers, D. Sengupta, A. S. Shawhan, P. Shoemaker, D. H. Sibley, A. Siemens, X. Sigg, D. Sintes, A. M. Smith, J. Smith, M. R. Spjeld, O. Strain, K. A. Strom, D. M. Stuver, A. Summerscales, T. Sung, M. Sutton, P. J. Tanner, D. B. Tarallo, M. Taylor, R. Thorne, K. A. Thorne, K. S. Tokmakov, K. V. Torres, C. Torrie, C. Traylor, G. Tyler, W. Ugolini, D. Ungarelli, C. Vallisneri, M. van Putten, M. Vass, S. Vecchio, A. Veitch, J. Vorvick, C. Vyachanin, S. P. Wallace, L. Ward, H. Ward, R. Watts, K. Webber, D. Weiland, U. Weinstein, A. Weiss, R. Wen, S. Wette, K. Whelan, J. T. Whitcomb, S. E. Whiting, B. F. Wiley, S. Wilkinson, C. Willems, P. A. Willke, B. Wilson, A. Winkler, W. Wise, S. Wiseman, A. G. Woan, G. Woods, D. Wooley, R. Worden, J. Yakushin, I. Yamamoto, H. Yoshida, S. Zanolin, M. Zhang, L. Zotov, N. Zucker, M. Zweizig, J. TI Search for gravitational-wave bursts in LIGO's third science run SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 6th Edoardo Amaldi Conference on Gravitational Waves CY JUN 20-24, 2005 CL Okinawa, JAPAN SP IUPAP, Okinawa Prefecture, Inoue Fdn Sci, Fdn Promot Astron ID ROTATIONAL CORE COLLAPSE; PERFORMANCE AB We report on a search for gravitational-wave bursts in data from the three LIGO interferometric detectors during their third science run. The search targets subsecond bursts in the frequency range 100-1100 Hz for which no waveform model is assumed and has a sensitivity in terms of the root-sum-square (rss) strain amplitude of h(rss) similar to 10(-20) Hz(-1/2). No gravitational-wave signals were detected in the eight days of analysed data. C1 CALTECH, LIGO, Pasadena, CA 91125 USA. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-30167 Hannover, Germany. Univ Wisconsin, Milwaukee, WI 53201 USA. MIT, LIGO, Cambridge, MA 02139 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Penn State Univ, University Pk, PA 16802 USA. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. Cardiff Univ, Cardiff CF2 3YB, Wales. Carleton Coll, Northfield, MN 55057 USA. LIGO Hanford Observ, Richland, WA 99352 USA. Northwestern Univ, Evanston, IL 60208 USA. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. LIGO Livingston Observ, Livingston, LA 70754 USA. Washington State Univ, Pullman, WA 99164 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Syracuse Univ, Syracuse, NY 13244 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. Stanford Univ, Stanford, CA 94305 USA. Univ Texas, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. CALTECH, Pasadena, CA 91125 USA. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. Embry Riddle Aeronaut Univ, Prescott, AZ 86301 USA. Natl Astron Observ Japan, Tokyo 1818588, Japan. Univ Illes Balears, E-07122 Palma de Mallorca, Spain. Columbia Univ, New York, NY 10027 USA. Australian Natl Univ, Canberra, ACT 0200, Australia. Loyola Univ, New Orleans, LA 70118 USA. Interuniv Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. Vassar Coll, Poughkeepsie, NY 12604 USA. CALTECH CaRT, Pasadena, CA 91125 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Trinity Univ, San Antonio, TX 78212 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. RP Abbott, B (reprint author), CALTECH, LIGO, Pasadena, CA 91125 USA. RI Allen, Bruce/K-2327-2012; Chen, Yanbei/A-2604-2013; Barker, David/A-5671-2013; Pitkin, Matthew/I-3802-2013; Liu, Sheng/K-2815-2013; Vyatchanin, Sergey/J-2238-2012; van Putten, Maurice/F-5237-2011; Vecchio, Alberto/F-8310-2015; Ottaway, David/J-5908-2015; Messaritaki, Eirini/D-7393-2016; Sigg, Daniel/I-4308-2015; Frey, Raymond/E-2830-2016; Ward, Robert/I-8032-2014; Agresti, Juri/G-8168-2012; Mitrofanov, Valery/D-8501-2012; McClelland, David/E-6765-2010; Schutz, Bernard/B-1504-2010; Casey, Morag/C-9703-2010; Bilenko, Igor/D-5172-2012; Rowan, Sheila/E-3032-2010; Strain, Kenneth/D-5236-2011; Raab, Frederick/E-2222-2011; Lueck, Harald/F-7100-2011; Kawabe, Keita/G-9840-2011; Tarallo, Marco/B-2096-2012; Finn, Lee Samuel/A-3452-2009 OI Allen, Bruce/0000-0003-4285-6256; Pitkin, Matthew/0000-0003-4548-526X; Vecchio, Alberto/0000-0002-6254-1617; Sigg, Daniel/0000-0003-4606-6526; Frey, Raymond/0000-0003-0341-2636; Aulbert, Carsten/0000-0002-1481-8319; Veitch, John/0000-0002-6508-0713; Papa, M.Alessandra/0000-0002-1007-5298; Ward, Robert/0000-0001-5503-5241; Whelan, John/0000-0001-5710-6576; Zweizig, John/0000-0002-1521-3397; O'Shaughnessy, Richard/0000-0001-5832-8517; Fairhurst, Stephen/0000-0001-8480-1961; Agresti, Juri/0000-0001-6119-2470; McClelland, David/0000-0001-6210-5842; Strain, Kenneth/0000-0002-2066-5355; Lueck, Harald/0000-0001-9350-4846; Tarallo, Marco/0000-0001-5169-4987; Finn, Lee Samuel/0000-0002-3937-0688 NR 13 TC 32 Z9 32 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 EI 1361-6382 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD APR 21 PY 2006 VL 23 IS 8 SI SI BP S29 EP S39 DI 10.1088/0264-9381/23/8/S05 PG 11 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 046XQ UT WOS:000237844800006 ER PT J AU Kawamura, S Nakamura, T Ando, M Seto, N Tsubono, K Numata, K Takahashi, R Nagano, S Ishikawa, T Musha, M Ueda, K Sato, T Hosokawa, M Agatsuma, K Akutsu, T Aoyanagi, K Arai, K Araya, A Asada, H Aso, Y Chiba, T Ebisuzaki, T Eriguchi, Y Fujimoto, MK Fukushima, M Futamase, T Ganzu, K Harada, T Hashimoto, T Hayama, K Hikida, W Himemoto, Y Hirabayashi, H Hiramatsu, T Ichiki, K Ikegami, T Inoue, KT Ioka, K Ishidoshiro, K Itoh, Y Kamagasako, S Kanda, N Kawashima, N Kirihara, H Kiuchi, K Kobayashi, S Kohri, K Kojima, Y Kokeyama, K Kozai, Y Kudoh, H Kunimori, H Kuroda, K Maeda, K Matsuhara, H Mino, Y Miyakawa, O Miyoki, S Mizusawa, H Morisawa, T Mukohyama, S Naito, I Nakagawa, N Nakamura, K Nakano, H Nishizawa, A Niwa, Y Nozawa, C Ohashi, M Ohishi, N Ohkawa, M Okutomi, A Oohara, K Sago, N Saijo, M Sakagami, M Sakata, S Sasaki, M Sato, S Shibata, M Shinkai, H Somiya, K Sotani, H Sugiyama, N Tagoshi, H Takahashi, T Takahashi, H Takahashi, R Takano, T Tanaka, T Taniguchi, K Taruya, A Tashiro, H Tokunari, M Tsujikawa, S Tsunesada, Y Yamamoto, K Yamazaki, T Yokoyama, J Yoo, CM Yoshida, S Yoshino, T AF Kawamura, Seiji Nakamura, Takashi Ando, Masaki Seto, Naoki Tsubono, Kimio Numata, Kenji Takahashi, Ryuichi Nagano, Shigeo Ishikawa, Takehiko Musha, Mitsuru Ueda, Ken-ichi Sato, Takashi Hosokawa, Mizuhiko Agatsuma, Kazuhiro Akutsu, Tomotada Aoyanagi, Koh-suke Arai, Koji Araya, Akito Asada, Hideki Aso, Yoichi Chiba, Takeshi Ebisuzaki, Toshikazu Eriguchi, Yoshiharu Fujimoto, Masa-Katsu Fukushima, Mitsuhiro Futamase, Toshifumi Ganzu, Katsuhiko Harada, Tomohiro Hashimoto, Tatsuaki Hayama, Kazuhiro Hikida, Wataru Himemoto, Yoshiaki Hirabayashi, Hisashi Hiramatsu, Takashi Ichiki, Kiyotomo Ikegami, Takeshi Inoue, Kaiki T. Ioka, Kunihito Ishidoshiro, Koji Itoh, Yousuke Kamagasako, Shogo Kanda, Nobuyuki Kawashima, Nobuki Kirihara, Hiroyuki Kiuchi, Kenta Kobayashi, Shiho Kohri, Kazunori Kojima, Yasufumi Kokeyama, Keiko Kozai, Yoshihide Kudoh, Hideaki Kunimori, Hiroo Kuroda, Kazuaki Maeda, Kei-ichi Matsuhara, Hideo Mino, Yasushi Miyakawa, Osamu Miyoki, Shinji Mizusawa, Hiromi Morisawa, Toshiyuki Mukohyama, Shinji Naito, Isao Nakagawa, Noriyasu Nakamura, Kouji Nakano, Hiroyuki Nishizawa, Atsushi Niwa, Yoshito Nozawa, Choetsu Ohashi, Masatake Ohishi, Naoko Ohkawa, Masashi Okutomi, Akira Oohara, Kenichi Sago, Norichika Saijo, Motoyuki Sakagami, Masaaki Sakata, Shihori Sasaki, Misao Sato, Shuichi Shibata, Masaru Shinkai, Hisaaki Somiya, Kentaro Sotani, Hajime Sugiyama, Naoshi Tagoshi, Hideyuki Takahashi, Tadayuki Takahashi, Hirotaka Takahashi, Ryutaro Takano, Tadashi Tanaka, Takahiro Taniguchi, Keisuke Taruya, Atsushi Tashiro, Hiroyuki Tokunari, Masao Tsujikawa, Shinji Tsunesada, Yoshiki Yamamoto, Kazuhiro Yamazaki, Toshitaka Yokoyama, Jun'ichi Yoo, Chul-Moon Yoshida, Shijun Yoshino, Taizoh TI The Japanese space gravitational wave antenna - DECIGO SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article; Proceedings Paper CT 6th Edoardo Amaldi Conference on Gravitational Waves CY JUN 20-24, 2005 CL Okinawa, JAPAN SP IUPAP, Okinawa Prefecture, Inoue Fdn Sci, Fdn Promot Astron AB DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. It aims at detecting various kinds of gravitational waves between 1 mHz and 100 Hz frequently enough to open a new window of observation for gravitational wave astronomy. The preconceptual design of DECIGO consists of three drag-free satellites, 1000 km apart from each other, whose relative displacements are measured by a Fabry-Perot Michelson interferometer. We plan to launch DECIGO in 2024 after a long and intense development phase, including two pathfinder missions for verification of required technologies. C1 Natl Astron Observ Japan, Mitaka, Tokyo 1818588, Japan. Kyoto Univ, Grad Sch Sci, Kyoto 6068502, Japan. Univ Tokyo, Grad Sch Sci, Bunkyo Ku, Tokyo 1130033, Japan. CALTECH, Pasadena, CA 91125 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Inst Informat & Commun Technol, Koganei, Tokyo 1848795, Japan. Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Tsukuba, Ibaraki 3058505, Japan. Univ Electrocommun, Inst Laser Sci, Chofu, Tokyo 1828585, Japan. Niigata Univ, Fac Engn, Niigata 9502181, Japan. Waseda Univ, Shinjuku Ku, Tokyo 1698555, Japan. Univ Tokyo, Earthquake Res Inst, Bunkyo Ku, Tokyo 1130032, Japan. Hirosaki Univ, Fac Sci & Technol, Hirosaki, Aomori 0368560, Japan. Nihon Univ, Coll Humanities & Sci, Setagaya Ku, Tokyo 1568550, Japan. RIKEN, Wako, Saitama 3510198, Japan. Univ Tokyo, Grad Sch Arts & Sci, Meguro Ku, Tokyo 1538902, Japan. Tohoku Univ, Grad Sch Sci, Sendai, Miyagi 9808578, Japan. Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Kyoto Univ, Yukawa Inst Theoret Phys, Kyoto 6068502, Japan. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058563, Japan. Kinki Univ, Sch Sci & Engn, Osaka 5778502, Japan. Univ Wisconsin, Milwaukee, WI 53201 USA. Osaka City Univ, Grad Sch Sci, Osaka 5588585, Japan. Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead L41 1LD, Merseyside, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Hiroshima Univ, Grad Sch Sci, Hiroshima 7398526, Japan. Ochanomizu Univ, Grad Sch Humanities & Sci, Bunkyo Ku, Tokyo 1128610, Japan. Gunma Astron Observ, Gunma 3770702, Japan. Natl Inst Informat & Commun Technol, Bunkyo Ku, Tokyo 1130001, Japan. Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. Niigata Univ, Fac Sci, Niigata 9502181, Japan. Kyoto Univ, Fac Intergrated Human Studies, Kyoto 6068501, Japan. Osaka Univ, Grad Sch Sci, Toyonaka, Osaka 5600043, Japan. Observ Paris, Sect Meudon, F-92195 Meudon, France. INAMORI Fdn, Kyoto 6008411, Japan. Max Planck Inst Gravitat Phys, D-14476 Potsdam, Germany. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Tokyo Inst Technol, Grad Sch Sci & Engn, Meguro Ku, Tokyo 1528550, Japan. RP Kawamura, S (reprint author), Natl Astron Observ Japan, Mitaka, Tokyo 1818588, Japan. EM seiji.kawamura@nao.ac.jp RI Chiba, Takeshi/G-3510-2011; Mukohyama, Shinji/A-4401-2011; Taniguchi, Keisuke/G-2694-2011; Takahashi, Ryuichi/F-3362-2013; Nakamura, Kouji/H-6364-2013; ANDO, MASAKI/G-4989-2014; Ebisuzaki, Toshikazu/N-6998-2014; OI Chiba, Takeshi/0000-0002-9737-2569; Nakamura, Kouji/0000-0001-6148-4289; ANDO, MASAKI/0000-0002-8865-9998; Ebisuzaki, Toshikazu/0000-0002-3918-1166; Nishizawa, Atsushi/0000-0003-3562-0990; Nakano, Hiroyuki/0000-0001-7665-0796 NR 4 TC 135 Z9 138 U1 2 U2 20 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 EI 1361-6382 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD APR 21 PY 2006 VL 23 IS 8 SI SI BP S125 EP S131 DI 10.1088/0264-9381/23/8/S17 PG 7 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 046XQ UT WOS:000237844800018 ER PT J AU Haguenauer, P Serabyn, E AF Haguenauer, P Serabyn, E TI Deep nulling of laser light with a single-mode-fiber beam combiner SO APPLIED OPTICS LA English DT Article ID EXTRASOLAR PLANETS; INTERFEROMETER; NULLER AB The detection of faint companions to bright stars requires the development of very-high-contrast-ratio detection techniques such as nulling interferometry. Here we present, to our knowledge, the first experimental test of a novel beam-combination method, which is based on coupling the light at the center of a dual-aperture interference pattern into a single-mode fiber. Using such a "fiber nuller" approach, a visible He-Ne laser has been stably nulled to as low as 1.3 X 10(-6), thus validating the approach. (c) 2006 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Haguenauer, P (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM phaguena@eso.org NR 22 TC 22 Z9 22 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 20 PY 2006 VL 45 IS 12 BP 2749 EP 2754 DI 10.1364/AO.45.002749 PG 6 WC Optics SC Optics GA 039HO UT WOS:000237296800023 PM 16633425 ER PT J AU Eriksen, HK Dickinson, C Lawrence, CR Baccigalupi, C Banday, AJ Gorski, KM Hansen, FK Lilje, PB Pierpaoli, E Seiffert, MD Smith, KM Vanderlinde, K AF Eriksen, HK Dickinson, C Lawrence, CR Baccigalupi, C Banday, AJ Gorski, KM Hansen, FK Lilje, PB Pierpaoli, E Seiffert, MD Smith, KM Vanderlinde, K TI Cosmic microwave background component separation by parameter estimation SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmology : observations; methods : numerical ID PROBE WMAP OBSERVATIONS; INTERSTELLAR-MEDIUM EMISSION; RADIO-CONTINUUM EMISSION; ANISOTROPY-PROBE; POWER SPECTRUM; COSMOLOGICAL PARAMETERS; SKY MAPS; COBE; FOREGROUNDS; DUST AB We propose a method for CMB component separation based on standard Bayesian parameter estimation techniques. We assume a parametric spectral model for each signal component and fit the corresponding parameters pixel by pixel in a two-stage process. First we fit for the full parameter set (e.g., component amplitudes and spectral indices) in low-resolution and high signal-to-noise ratio maps using MCMC, obtaining both best-fit values for each parameter and the associated uncertainty. The goodness of fit is approximated by a chi(2) statistic. Then we fix all nonlinear parameters at their low-resolution best-fit values and solve analytically for high-resolution component amplitude maps. This likelihood approach has many advantages: the fitted model may be chosen freely, and the method is therefore completely general; all assumptions are transparent; no restrictions on spatial variations of foreground properties are imposed; the results may be monitored by goodness-of-fit tests; and, most importantly, we obtain reliable error estimates on all estimated quantities. We apply the method to simulated Planck satellite and 6 year WMAP data based on realistic models and show that separation at the microkelvin level is indeed possible in these cases. We also outline how the foreground uncertainties may be rigorously propagated through to the CMB power spectrum and cosmological parameters using a Gibbs sampling technique. C1 Univ Oslo, Inst Theoret Astrophys, N-0315 Oslo, Norway. Univ Oslo, Ctr Math Applicat, N-0316 Oslo, Norway. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. SISSA, ISAS, Astrophys Sector, I-34014 Trieste, Italy. Ist Nazl Fis Nucl, Sez Trieste, I-34014 Trieste, Italy. Univ Heidelberg, Inst Theoret Astrophys, D-69120 Heidelberg, Germany. Max Planck Inst Astrophys, D-85741 Garching, Germany. Univ Warsaw Observ, PL-00478 Warsaw, Poland. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Univ Chicago, Kavli Inst Cosmol Phys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Eriksen, HK (reprint author), Univ Oslo, Inst Theoret Astrophys, POB 1029, N-0315 Oslo, Norway. EM h.k.k.eriksen@astro.uio.no; cdickins@astro.caltech.edu; charles.r.lawrence@jpl.nasa.gov; bacci@sissa.it; banday@MPA-Garching.MPG.DE; Krzysztof.M.Gorski@jpl.nasa.gov; f.k.hansen@astro.uio.no; per.lilje@astro.uio.no; pierpa@caltech.edu; Michael.D.Seiffert@jpl.nasa.gov; kmsmith@uchicago.edu; kvand@uchicago.edu RI Lilje, Per/A-2699-2012; OI Lilje, Per/0000-0003-4324-7794; Pierpaoli, Elena/0000-0002-7957-8993 NR 54 TC 65 Z9 65 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 665 EP 682 DI 10.1086/500499 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400003 ER PT J AU Sambruna, RM Gliozzi, M Donato, D Maraschi, L Tavecchio, F Cheung, CC Urry, CM Wardle, JFC AF Sambruna, RM Gliozzi, M Donato, D Maraschi, L Tavecchio, F Cheung, CC Urry, CM Wardle, JFC TI Deep Chandra and multicolor HST follow-up of the jets in two powerful radio quasars SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : jets; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; HUBBLE-SPACE-TELESCOPE; LARGE-SCALE JETS; X-RAY-EMISSION; EXTRAGALACTIC JETS; SYNCHROTRON; RADIATION; COMPTON; MAPS; VLA AB We present deep (70-80 ks) Chandra and multicolor HST ACS images of two jets hosted by the powerful quasars 1136-135 and 1150+497, together with new radio observations. The sources have an FR II morphology and were selected from our previous X-ray and optical jet survey for detailed follow-up aimed at obtaining better constraints on the jet multiwavelength morphology and X-ray and optical spectra of individual knots and to test emission models to derive physical parameters more accurately. All the X-ray and optical knots detected in our previous short exposures are confirmed, together with a few new faint features. The overlaid maps and the emissivity profiles along the jet show good correspondence between emission regions at the various wavelengths; a few show offsets between the knot peaks of < 1". In 1150+497 the X-ray, optical, and radio profiles decrease in similar ways with distance from the core up to similar to 7", after which the radio emission increases more than does the X-ray one. No X-ray spectral variations are observed in 1150+497. In 1136-135 an interesting behavior is observed, whereby, downstream of the most prominent knot at similar to 6"5 from the core, the X-ray emission fades, while the radio emission brightens. The X-ray spectrum also varies, with the X-ray photon index flattening from Gamma(X) similar to 2 in the inner part to Gamma(X) similar to 1.7 to the end of the jet. We interpret the jet behavior in 1136-135 in a scenario in which the relativistic flow suffers systematic deceleration along the jet, and we briefly discuss the major consequences of this scenario. The latter is discussed in more detail in our companion paper (Tavecchio et al.). C1 George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. Osserv Astron Brera, I-20121 Milan, Italy. MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. Brandeis Univ, Dept Phys, Waltham, MA 02454 USA. RP NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM rms@milkyway.gsfc.nasa.gov RI Urry, Claudia/G-7381-2011 OI Urry, Claudia/0000-0002-0745-9792 NR 34 TC 27 Z9 27 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 717 EP 731 DI 10.1086/500526 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400007 ER PT J AU Tavecchio, F Maraschi, L Sambruna, RM Gliozzi, M Cheung, CC Wardle, JFC Urry, CM AF Tavecchio, F Maraschi, L Sambruna, RM Gliozzi, M Cheung, CC Wardle, JFC Urry, CM TI Deceleration from entrainment in the jet of the quasar 1136-135? SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : jets; quasars : individual ( PKS 1136-135); X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; LARGE-SCALE JETS; HUBBLE-SPACE-TELESCOPE; EXTENDED RADIO JETS; X-RAY-EMISSION; RELATIVISTIC JETS; HOT-SPOTS; EXTRAGALACTIC JETS; GALAXY 3C-31; LAC OBJECTS AB By modeling the multiwavelength emission of successive regions in the jet of the quasar PKS 1136-135, we find indications that the jet suffers deceleration near its end on a (deprojected) scale of similar to 400 kpc. We adopt a continuous flow approximation, and we discuss the possibility that the inferred deceleration from a Lorentz factor of Gamma = 6.5 to 2.5 is induced by entrainment of external gas. Some consequences of this scenario are discussed. C1 Osserv Astron Brera, I-20121 Milan, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Brandeis Univ, Dept Phys, Waltham, MA 02454 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. RP Osserv Astron Brera, Via Brera 28, I-20121 Milan, Italy. RI Urry, Claudia/G-7381-2011 OI Urry, Claudia/0000-0002-0745-9792 NR 42 TC 21 Z9 21 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 732 EP 739 DI 10.1086/500536 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400008 ER PT J AU Tanner, A Figer, DF Najarro, F Kudritzki, RP Gilmore, D Morris, M Becklin, EE McLean, IS Gilbert, AM Graham, JR Larkin, JE Levenson, NA Teplitz, HI AF Tanner, A Figer, DF Najarro, F Kudritzki, RP Gilmore, D Morris, M Becklin, EE McLean, IS Gilbert, AM Graham, JR Larkin, JE Levenson, NA Teplitz, HI TI High spectral resolution observations of the massive stars in the Galactic center SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxy : center; infrared : stars; stars : early-type; stars : Wolf-Rayet ID SUPERMASSIVE BLACK-HOLE; NEAR-INFRARED SPECTRA; WOLF-RAYET STARS; HOT STARS; NICMOS OBSERVATIONS; DYNAMICAL FRICTION; STELLAR DYNAMICS; ARCHES CLUSTER; HELIUM STARS; MILKY-WAY AB We present high-resolution near-infrared spectra, obtained with the NIRSPEC spectrograph on the W. M. Keck II Telescope, of a collection of hot, massive stars within the central 25" of the Galactic center. We have identified a total of 21 emission-line stars, seven of which are new radial velocity detections, with five of those being classified as He I emission-line stars for the first time. These stars fall into two categories based on their spectral properties: (1) those with narrow 2.112, 2.113 mu m He I doublet absorption lines, and (2) those with broad 2.058 mu m He I emission lines. These data have the highest spectral resolution ever obtained for these sources and, as a result, both components of the absorption doublet are separately resolved for the first time. We use these spectral features to measure radial velocities. The majority of the measured radial velocities have relative errors of 20 km s(-1), smaller than those previously obtained with proper-motion or radial velocity measurements for similar stellar samples in the Galactic center. The radial velocities estimated from the He I absorption doublet are more robust than those previously estimated from the 2.058 mu m emission line, since they do not suffer from confusion due to emission from the surrounding ISM. Using this velocity information, we agree with previous stellar velocity studies that the stars are orbiting in a somewhat coherent manner but are not as defined into a disk or disks as previously thought. Finally, multiepoch radial velocity measurements for IRS 16NE show a change in its velocity, presumably due to an unseen stellar companion. C1 Jet Prop Lab, Pasadena, CA 91106 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CSIC, Inst Estructura Mat, E-28006 Madrid, Spain. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Calif Los Angeles, Dept Astron & Astrophys, Los Angeles, CA 90095 USA. Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. RP Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91106 USA. EM angelle.tanner@jpl.nasa.gov RI Najarro, Francisco/G-7288-2015; OI Najarro, Francisco/0000-0002-9124-0039; Levenson, Nancy A./0000-0003-4209-639X NR 61 TC 19 Z9 19 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 891 EP 904 DI 10.1086/500498 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400022 ER PT J AU Finkelstein, SL Morse, JA Green, JC Linsky, JL Shull, JM Snow, TP Stocke, JT Brownsberger, KR Ebbets, DC Wilkinson, E Heap, SR Leitherer, C Savage, BD Siegmund, OH Stern, A AF Finkelstein, SL Morse, JA Green, JC Linsky, JL Shull, JM Snow, TP Stocke, JT Brownsberger, KR Ebbets, DC Wilkinson, E Heap, SR Leitherer, C Savage, BD Siegmund, OH Stern, A TI Optical structure and proper-motion age of the oxygen-rich supernova remnant 1E 0102-7219 in the small magellanic cloud SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (1E 0102-7219); stars : Wolf-Rayet; supernova remnants ID HUBBLE-SPACE-TELESCOPE; WOLF-RAYET STARS; CASSIOPEIA-A; 1E 0102.2-7219; YOUNG; 1E-0102.2-7219; SPECTRUM; EJECTA; SHOCK; SPECTROSCOPY AB We present new optical emission-line images of the young SNR 1E 0102-7219 in the SMC obtained with the ACS on HST. This object is a member of the oxygen-rich class of SNRs showing strong oxygen, neon, and other metalline emissions in its optical and X-ray spectra, and an absence of hydrogen and helium. The progenitor of 1E 0102-7219 may have been a Wolf-Rayet star that underwent considerable mass loss prior to exploding as a Type Ib/c or IIL/b supernova. The ejecta in this SNR are generally fast-moving (V > 1000 km s(-1)) and emit as they are compressed and heated in the reverse shock. In 2003 we obtained optical [O III], H alpha, and continuum images with the ACS Wide Field Camera. The [O III] image through the F475W filter captures the full velocity range of the ejecta and shows considerable high-velocity emission projected in the middle of the SNR that was Doppler-shifted out of the narrow F502N bandpass of a previous WFPC2 image from 1995. Using these two epochs separated by similar to 8.5 yr, we measure the transverse expansion of the ejecta around the outer rim in this SNR for the first time at visible wavelengths. From proper-motion measurements of 12 ejecta filaments, we estimate a mean expansion velocity for the bright ejecta of similar to 2000 km s(-1) and an inferred kinematic age for the SNR of similar to 2050 +/- 600 yr. The age we derive from HST data is about twice that inferred by Hughes et al. from X-ray data, although our 1 sigma error bars overlap. Our proper-motion age is consistent with an independent optical kinematic age derived by Eriksen et al. in 2003 using spatially resolved [O III] radial-velocity data. We derive an expansion center that lies very close to conspicuous X-ray and radio hot spots, which could indicate the presence of a compact remnant (neutron star or black hole). C1 Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85281 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. Ball Aerosp & Technol Corp, Boulder, CO 80306 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. SW Res Inst, Boulder, CO 80302 USA. RP Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85281 USA. NR 46 TC 14 Z9 14 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 919 EP 929 DI 10.1086/500570 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400024 ER PT J AU Falcone, AD Burrows, DN Lazzati, D Campana, S Kobayashi, S Zhang, B Meszaros, P Page, KL Kennea, JA Romano, P Pagani, C Angelini, L Beardmore, AP Capalbi, M Chincarini, G Cusumano, G Giommi, P Goad, MR Godet, O Grupe, D Hill, JE La Parola, V Mangano, V Moretti, A Nousek, JA O'Brien, PT Osborne, JP Perri, M Tagliaferri, G Wells, AA Gehrels, N AF Falcone, AD Burrows, DN Lazzati, D Campana, S Kobayashi, S Zhang, B Meszaros, P Page, KL Kennea, JA Romano, P Pagani, C Angelini, L Beardmore, AP Capalbi, M Chincarini, G Cusumano, G Giommi, P Goad, MR Godet, O Grupe, D Hill, JE La Parola, V Mangano, V Moretti, A Nousek, JA O'Brien, PT Osborne, JP Perri, M Tagliaferri, G Wells, AA Gehrels, N TI The giant X-ray flare of GRB 050502B: Evidence for late-time internal engine activity SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; X-rays : bursts ID BURST AFTERGLOWS; BATSE OBSERVATIONS; TELESCOPE; EMISSION; LONG; ABSORPTION; MISSION; DENSITY AB Until recently, X-ray flares during the afterglow of gamma-ray bursts (GRBs) were a rarely detected phenomenon; thus, their nature is unclear. During the afterglow of GRB 050502B, the largest X-ray flare ever recorded rose rapidly above the afterglow light curve detected by the Swift X-Ray Telescope. The peak flux of the flare was > 500 times that of the underlying afterglow, and it occurred > 12 minutes after the nominal prompt burst emission. The fluence of this X-ray flare, (1.0 +/- 0.05) x 10(-6) ergs cm(-2) in the 0.2 - 10.0 keV energy band, exceeded the fluence of the nominal prompt burst. The spectra during the flare were significantly harder than those measured before and after the flare. Later in time, there were additional flux increases detected above the underlying afterglow, as well as a break in the afterglow light curve. All evidence presented below, including spectral and, particularly, timing information during and around the giant flare, suggests that this giant flare was the result of internal dissipation of energy due to late central engine activity, rather than an afterglow-related effect. We also find that the data are consistent with a second central engine activity episode, in which the ejecta is moving slower than that of the initial episode, causing the giant flare and then proceeding to overtake and refresh the afterglow shock, thus causing additional activity at even later times in the light curve. C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. INAF, Osservatorio Astron Brera, Merate, Italy. Penn State Univ, Ctr Gravitat Wave Phys, University Pk, PA 16802 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. ASI Sci Data Ctr, Frascati, Italy. Univ Milan, Dipartimento Fis, I-20122 Milan, Italy. Ist Fis Spazialee Fis Cosm, Sez Palermo, INAF, Palermo, Italy. Univ Leicester, Ctr Space Res, Leicester LE1 7RH, Leics, England. RP Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. EM afalcone@astro.psu.edu RI Gehrels, Neil/D-2971-2012; OI giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 42 TC 120 Z9 122 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 1010 EP 1017 DI 10.1086/500655 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400033 ER PT J AU Folatelli, G Contreras, C Phillips, MM Woosley, SE Blinnikov, S Morrell, N Suntzeff, NB Lee, BL Hamuy, M Gonzalez, S Krzeminski, W Roth, M Li, WD Filippenko, AV Foley, RJ Freedman, WL Madore, BF Persson, SE Murphy, D Boissier, S Galaz, G Gonzalez, L McCarthy, PJ McWilliam, A Pych, W AF Folatelli, G Contreras, C Phillips, MM Woosley, SE Blinnikov, S Morrell, N Suntzeff, NB Lee, BL Hamuy, M Gonzalez, S Krzeminski, W Roth, M Li, WD Filippenko, AV Foley, RJ Freedman, WL Madore, BF Persson, SE Murphy, D Boissier, S Galaz, G Gonzalez, L McCarthy, PJ McWilliam, A Pych, W TI Sn 2005bf: A possible transition event between type Ib/c supernovae and gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; supernovae : individual (SN 2005bf) ID MASSIVE STARS; LIGHT CURVES; OPTICAL PHOTOMETRY; STANDARD STARS; EVOLUTION; SPECTROSCOPY; SPECTRA; SPECTROPHOTOMETRY; TELESCOPE; EXPLOSION AB We present u'g'r'i'BV photometry and optical spectroscopy of the Type Ib/Ic SN 2005bf covering the first similar to 100 days following discovery. The u'g'BV light curves displayed an unprecedented morphology among Type Ib/Ic supernovae, with an initial maximum some 2 weeks after discovery and a second, main maximum about 25 days after that. The bolometric light curve indicates that SN 2005bf was a remarkably luminous event, radiating at least 6.3 x 10(42) ergs s(-1) at maximum light and a total of 2.1 x 10(49) ergs during the first 75 days after the explosion. Spectroscopically, SN 2005bf underwent a unique transformation from a Type Ic-like event at early times to a typical Type Ib supernova at later phases. The initial maximum in u'g'BV was accompanied by the presence in the spectrum of high-velocity (> 14,000 km s(-1)) absorption lines of Fe II, Ca II, and H I. The photospheric velocity derived from spectra at early epochs was below 10,000 km s(-1), which is unusually low compared with ordinary Type Ib supernovae. We describe one-dimensional computer simulations that attempt to account for these remarkable properties. The most favored model is that of a very energetic (2 x 10(51) ergs), asymmetric explosion of a massive ( 8.3 M-circle dot) Wolf-Rayet WN star that had lost most of its hydrogen envelope. We speculate that an unobserved relativistic jet was launched producing a two-component explosion consisting of ( 1) a polar explosion containing a small fraction of the total mass and moving at high velocity and ( 2) the explosion of the rest of the star. At first, only the polar explosion is observed, producing the initial maximum and the high-velocity absorption-line spectrum resembling a Type Ic event. At late times, this fast- moving component becomes optically thin, revealing the more slowly moving explosion of the rest of the star and transforming the observed spectrum to that of a typical Type Ib supernova. If this scenario is correct, then SN 2005bf is the best example to date of a transition object between normal Type Ib/Ic supernovae and gamma-ray bursts. C1 Las Campanas Observ, Carnegie Observ, La Serena, Chile. Univ Calif Santa Cruz, Dept Astron, Santa Cruz, CA 95064 USA. Max Planck Inst Astrophys, D-85741 Garching, Germany. Alikhanov Inst Theoret & Expt Phys, Moscow 117218, Russia. Cerro Tololo Interamer Observ, La Serena, Chile. Univ Toronto, Dept Astron & Astrophys, Toronto, ON M5S 3H8, Canada. Univ Chile, Dept Astron, Santiago, Chile. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. CALTECH, Jet Propuls Lab, Infrared Proc & Anal Ctr, Pasadena, CA 91125 USA. Pontificia Univ Catolica Chile, Dept Astron & Astrophys, Santiago 22, Chile. Copernicus Astron Ctr, PL-00716 Warsaw, Poland. RP Las Campanas Observ, Carnegie Observ, Casilla 601, La Serena, Chile. RI Folatelli, Gaston/A-4484-2011; Hamuy, Mario/G-7541-2016 NR 51 TC 68 Z9 68 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 1039 EP 1050 DI 10.1086/500531 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400036 ER PT J AU Ueta, T Murakawa, K Meixner, M AF Ueta, T Murakawa, K Meixner, M TI Proper-motion measurements of the Cygnus Egg Nebula SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; reflection nebulae; stars : AGB and post-AGB; stars : individual (AFGL 2688, CRL 2688, Egg Nebula, V1610 Cyg); stars : mass loss ID HUBBLE-SPACE-TELESCOPE; INTERMEDIATE-MASS STARS; ASYMPTOTIC GIANT BRANCH; BIPOLAR NEBULAE; PROTOPLANETARY NEBULAE; IMAGING POLARIMETRY; PLANETARY NEBULAE; ANGULAR EXPANSION; POLARIZED-LIGHT; MOLECULAR GAS AB We present the results of proper-motion measurements of the dust shell structure in the Egg Nebula (AFGL 2688, CRL 2688, V1610 Cyg), based on the archived two-epoch data at 2 mu m taken with the Hubble Space Telescope. We measured the amount of motion of local structures in the nebula by determining their relative shifts over an interval of 5.5 yr. The dynamical age of the nebula is found to be roughly 350 yr based on the overall Hubble-law-esque motion of the nebula. By adopting the deprojected velocity of 45 km s(-1) at the tips of the bipolar lobes, our proper-motion measurements indicate that the distance to the Egg Nebula is about 420 pc and that the lobes are inclined at 7.degrees 7 with respect to the plane of the sky. The refined distance estimate yields a luminosity of the central star of 3.3 x 10(3) L-circle dot, a total shell mass of 1.2 M-circle dot, and a mass-loss rate ( the upper limit) of 3.6 x 10(-3) M-circle dot yr(-1). Assuming a 0.6 M-circle dot central post-AGB stellar mass, the initial mass of the Egg is 1.8 M-circle dot. Upon analysis, we also discovered that (1) the central star of the Egg Nebula has a proper motion of its own at a rate of 17 mas yr(-1), (2) the tips of the lobes increased their velocity due to shock acceleration, and (3) the apparent bipolar lobes consist of multiple outflows at distinct inclination angles projected onto each other. C1 NASA, Ames Res Ctr, SOFIA, Moffett Field, CA 94035 USA. Max Planck Inst Radioastron, D-53121 Bonn, Germany. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Ueta, T (reprint author), NASA, Ames Res Ctr, SOFIA, Mail Stop 211-3, Moffett Field, CA 94035 USA. EM tueta@sofia.usra.edu NR 44 TC 21 Z9 21 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 1113 EP 1121 DI 10.1086/500642 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400042 ER PT J AU Saba, JLR Gaeng, T Tarbell, TD AF Saba, JLR Gaeng, T Tarbell, TD TI Analysis of solar flare ribbon evolution: A semiautomated approach SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : activity; Sun : corona; Sun : flares; Sun : magnetic fields ID MAGNETIC RECONNECTION; H-ALPHA; EXTREME-ULTRAVIOLET; ELECTRIC-FIELDS; FLUX; PROMINENCES; EMISSION; ERUPTION; KERNELS; PLASMA AB We exploit a rare joint set of high-resolution, very high cadence TRACE UV images and high-resolution magnetograms from SOHO MDI to investigate the dynamical properties of flare ribbons in a GOES M1 class flare from NOAA active region 9236 on 2000 November 23 at 23:28 UT. Assuming that flare ribbons locate the chromospheric footpoints of magnetic field lines reconnecting in the corona and that magnetic flux is conserved, we measure the magnetic reconnection rate ( in maxwells per second) by overlaying the ribbons on co-registered magnetograms and using intensity-based binary masks to track the magnetic flux swept over by the evolving ribbons, and by assumption swept up in the reconnection. In the event observed, the ribbons did not separate with time but remained stationary while they brightened, lengthened, and faded in place. Thus, the ribbons may be akin to hard X-ray flare kernels moving antiparallel to each other, which others interpret as caused by strong photospheric shear. The derived reconnection rate is noisy, with little correlation between adjacent 1.4 s samples; the peak rate for pixels summed over the ribbon is similar to 5 x 10(18) Mx s(-1); the average rise-phase rate is 10 times lower. The "local" rates for adjacent pixels added to the ribbon at adjacent times show correlations with 1600 angstrom band intensities, supporting the reconnection interpretation. For simple assumptions about geometry, the reconnection appears fast (V-in >= 0.01 V-A). The peak reconnection rates, along with estimates of the current-sheet length scale suggested by measured quantities, imply peak electric fields of order 40 V cm(-1). We discuss caveats to these results. C1 Org ADBR, Lockheed Martin Solar & Astrophys Lab, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Global Sci & Technol Inc, Greenbelt, MD 20771 USA. Org ADBS, Lockheed Martin Solar & Astrophys Lab, Palo Alto, CA 94304 USA. RP Saba, JLR (reprint author), Org ADBR, Lockheed Martin Solar & Astrophys Lab, Mail Code 612-5, Greenbelt, MD 20771 USA. EM julia.saba@gsfc.nasa.gov; thomas.gaeng@gsfc.nasa.gov; ted.tarbell@lmco.com NR 31 TC 20 Z9 20 U1 1 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2006 VL 641 IS 2 BP 1197 EP 1209 DI 10.1086/500631 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AV UT WOS:000236819400050 ER PT J AU Hartle, RE Sittler, EC Neubauer, FM Johnson, RE Smith, HT Crary, F McComas, DJ Young, DT Coates, AJ Simpson, D Bolton, S Reisenfeld, D Szego, K Berthelier, JJ Rymer, A Vilppola, J Steinberg, JT Andre, N AF Hartle, RE Sittler, EC Neubauer, FM Johnson, RE Smith, HT Crary, F McComas, DJ Young, DT Coates, AJ Simpson, D Bolton, S Reisenfeld, D Szego, K Berthelier, JJ Rymer, A Vilppola, J Steinberg, JT Andre, N TI Preliminary interpretation of Titan plasma interaction as observed by the Cassini Plasma Spectrometer: Comparisons with Voyager 1 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MAGNETIC-FIELD; ION; SATURN AB The Cassini Plasma Spectrometer (CAPS) instrument observed the plasma environment at Titan during the Cassini orbiter's TA encounter on October 26, 2004. Titan was in Saturn's magnetosphere during the Voyager 1 flyby and also during the TA encounter. CAPS measurements from this encounter are compared with measurements made by the Voyager 1 Plasma Science Instrument (PLS). The comparisons focus on the composition and nature of ambient and pickup ions. They lead to: A) the major ion components of Saturn's magnetosphere in the vicinity of Titan are H+, H-2(+) and O+/CH4+ ions; B) finite gyroradius effects are apparent in ambient O+ ions as the result of their absorption by Titan's extended atmosphere; C) the principal pickup ions are composed of H+, H-2(+), N+/CH2+, CH4+, and N-2(+); D) the pickup ions are in narrow energy ranges; and E) there is clear evidence of the slowing down of background ions due to pickup ion mass loading. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Cologne, Inst Geophys & Meteorol, D-50923 Cologne, Germany. Univ Virginia, Dept Engn, Charlottesville, VA 22904 USA. SW Res Inst, San Antonio, TX 78228 USA. Mullard Space Flight Ctr, Dorking RH5 6NT, Surrey, England. Jet Prop Lab, Pasadena, CA 91109 USA. Univ Montana, Dept Phys & Astron, Missoula, MT 59812 USA. KFKI RMKI, KFKI Res Inst Particle & Nucl Phys, H-1525 Budapest, Hungary. Ctr Etud Environm Terr & Planetaires, St Maur des Fosses, France. Univ Oulu, Dept Phys Sci, FIN-90014 Linnanmaa, Finland. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM richard.e.hartle@nasa.gov RI Coates, Andrew/C-2396-2008; Reisenfeld, Daniel/F-7614-2015; Smith, Howard/H-4662-2016 OI Coates, Andrew/0000-0002-6185-3125; Smith, Howard/0000-0003-3537-3360 NR 13 TC 32 Z9 32 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 20 PY 2006 VL 33 IS 8 AR L08201 DI 10.1029/2005GL024817 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 039LV UT WOS:000237308100001 ER PT J AU Jensen, EJ Ackerman, AS AF Jensen, EJ Ackerman, AS TI Homogeneous aerosol freezing in the tops of high-altitude tropical cumulonimbus clouds SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ICE NUCLEATION; CIRRUS; TROPOSPHERE; CONVECTION; TRANSPORT; MODEL; SIZE AB Numerical simulations of deep, intense continental tropical convection indicate that when the cloud tops extend more than a few kilometers above the liquid water homogeneous freezing level, ice nucleation due to freezing of entrained aqueous sulfate aerosols generates large concentrations of small crystals (diameters less than similar or equal to 20 mu m). The small crystals produced by aerosol freezing have the largest impact on cloud-top ice concentration for convective clouds with strong updrafts but relatively low aerosol concentrations. An implication of this result is that cloud-top ice concentrations in high anvil cirrus can be controlled primarily by updraft speeds in the tops of convective plumes and to a lesser extent by aerosol concentrations in the uppermost troposphere. While larger crystals precipitate out and sublimate in subsaturated air below, the population of small crystals can persist in the saturated uppermost troposphere for many hours, thereby prolonging the lifetime of remnants from anvil cirrus in the tropical tropopause layer. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Jensen, EJ (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM eric.j.jensen@nasa.gov; andrew.ackerman@nasa.gov RI Ackerman, Andrew/D-4433-2012 OI Ackerman, Andrew/0000-0003-0254-6253 NR 24 TC 13 Z9 15 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 20 PY 2006 VL 33 IS 8 AR L08802 DI 10.1029/2005GL024928 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039LV UT WOS:000237308100002 ER PT J AU Garcia, VMT Signorini, S Garcia, CAE McClain, CR AF Garcia, VMT Signorini, S Garcia, CAE McClain, CR TI Empirical and semi-analytical chlorophyll algorithms in the southwestern Atlantic coastal region (25-40 degrees S and 60-45 degrees W) SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID OCEAN-COLOR; CHESAPEAKE BAY; SEAWIFS DATA; MODEL; SEA; SURFACE; WATERS; SHELF; REFLECTANCE; VARIABILITY AB Global ocean colour algorithms, used to extract chlorophyll concentration in the ocean surface, normally overestimate pigment values in coastal regions, due to optical interference of water components. The objective of the present investigation was to test the performance of both empirical (SeaWiFS OC4v4) and semi-analytical (GSM01 and CARDER) algorithms in the south-western Atlantic. In situ pigment and optical data have been collected in waters influenced by continental discharge from La Plata River and Patos Lagoon. The data was used to develop a regional version of the empirical SeaWiFS OC2v4 algorithm (termed OC2-LP). The relative percentage difference (RPD) between in situ and algorithm-derived chlorophyll was 11% in the regional version as compared to the global OC4v4 (RPD=27%). The GSM01 and CARDER showed RPD of 14% and 31%, respectively. We have also tested the accuracy of the four algorithms (OC4v4, OC2-LP, GSM01 and CARDER) on SeaWiFS images taken over two cruise periods in the study region (winter of 2003 and summer of 2004). A seasonal difference was observed, where both OC4v4 and OC2-LP overestimate chlorophyll in summer at a higher magnitude than in winter, and the GSM01 algorithm showed a marked underestimation of chlorophyll in winter. The CARDER model showed a good performance both in winter and summer, when applied to satellite-retrieved radiances. Our results show that the use of semi-analytical models does not improve significantly the accuracy of chlorophyll retrievals in coastal areas when not properly tuned with regional inherent optical properties measurements. C1 Fed Univ Rio Grande, Dept Oceanog, BR-96201900 Rio Grande, RS, Brazil. Fed Univ Rio Grande, Dept Phys, BR-96201900 Rio Grande, RS, Brazil. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Garcia, VMT (reprint author), Fed Univ Rio Grande, Dept Oceanog, Av Italia Km 8, BR-96201900 Rio Grande, RS, Brazil. EM docvmtg@furg.br RI Tavano, Virginia/C-5241-2013; Garcia, Carlos/K-7382-2012 OI Tavano, Virginia/0000-0003-0039-8111; NR 42 TC 17 Z9 17 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD APR 20 PY 2006 VL 27 IS 8 BP 1539 EP 1562 DI 10.1080/01431160500382857 PG 24 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 041IH UT WOS:000237447600004 ER PT J AU Palosz, WF AF Palosz, WF TI Eastern European science needs sweeping changes SO NATURE LA English DT Letter C1 NASA, BAE Syst Analyt Solut, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Palosz, WF (reprint author), NASA, BAE Syst Analyt Solut, George C Marshall Space Flight Ctr, VP01, Huntsville, AL 35812 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 20 PY 2006 VL 440 IS 7087 BP 992 EP 992 DI 10.1038/440992c PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 034DL UT WOS:000236906000015 PM 16625174 ER PT J AU Garrett, TJ Dean-Day, J Liu, C Barnett, B Mace, G Baumgardner, D Webster, C Bui, T Read, W Minnis, P AF Garrett, TJ Dean-Day, J Liu, C Barnett, B Mace, G Baumgardner, D Webster, C Bui, T Read, W Minnis, P TI Convective formation of pileus cloud near the tropopause SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID ENVIRONMENT INTERFACE INSTABILITY; TROPICAL TROPOPAUSE; SPATIAL DIMENSIONS; CIRRUS CLOUDS; THIN CIRRUS; NASA ER-2; DEHYDRATION; ICE; AIRCRAFT; HUMIDITY AB Pileus clouds form where humid, vertically stratified air is mechanically displaced ahead of rising convection. This paper describes convective formation of pileus cloud in the tropopause transition layer (TTL), and explores a possible link to the formation of long-lasting cirrus at cold temperatures. The study examines in detail in-situ measurements from off the coast of Honduras during the July 2002 CRYSTAL-FACE experiment that showed an example of TTL cirrus associated with, and penetrated by, deep convection. The TTL cirrus was enriched with total water compared to its surroundings, but was composed of extremely small ice crystals with effective radii between 2 and 4 mu m. Through gravity wave analysis, and intercomparison of measured and simulated cloud microphysics, it is argued that the TTL cirrus originated neither from convectively-forced gravity wave motions nor environmental mixing alone. Rather, it is hypothesized that a combination of these two processes was involved in which, first, a pulse of convection forced pileus cloud to form from TTL air; second, the pileus layer was punctured by the convective pulse and received larger ice crystals through interfacial mixing; third, the addition of this condensate inhibited evaporation of the original pileus ice crystals where a convectively forced gravity wave entered its warm phase; fourth, through successive pulses of convection, a sheet of TTL cirrus formed. While the general incidence and longevity of pileus cloud remains unknown, in-situ measurements, and satellite-based Microwave Limb Sounder retrievals, suggest that much of the tropical TTL is sufficiently humid to be susceptible to its formation. Where these clouds form and persist, there is potential for an irreversible repartition from water vapor to ice at cold temperatures. C1 Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. NASA, Ames Res Ctr, Atmospher Chem & Dynam Branch, Moffett Field, CA USA. NASA, Lyndon B Johnson Space Ctr, Program Off WB57, Houston, TX 77058 USA. Univ Nacl Autonoma Mexico, Mexico City 04510, DF, Mexico. Jet Prop Lab, Pasadena, CA USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Garrett, TJ (reprint author), Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. EM tgarrett@met.utah.edu RI Minnis, Patrick/G-1902-2010 OI Minnis, Patrick/0000-0002-4733-6148 NR 44 TC 13 Z9 13 U1 1 U2 2 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 EI 1680-7324 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD APR 19 PY 2006 VL 6 BP 1185 EP 1200 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 034HV UT WOS:000236920800001 ER PT J AU Papa, F Prigent, C Durand, F Rossow, WB AF Papa, F Prigent, C Durand, F Rossow, WB TI Wetland dynamics using a suite of satellite observations: A case study of application and evaluation for the Indian Subcontinent SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID DISCHARGE AB Using a suite of satellite observations, including passive and active microwave along with visible and infrared observations developed to estimate wetlands on a global scale, the present study examine wetlands spatial and temporal dynamics over the Indian subcontinent, a region subject to an annual monsoon. Monthly wetlands extent estimates over a 2-year (1993-1994) period and their consistency are analyzed using independent data sets, such as rainfall rate in-situ rain-gauge observations and the Global Precipitation Climatology Project product, as well as river water levels derived from radar altimeter observations. The extent variations show a good agreement with the rain-gauge data, a high correlation with the GPCP rain data and a similar seasonal cycle with the altimeter estimates over the 2 years. This case study evaluation shows the potential of the remote sensing to give spatial-temporal consistent information on the variability of flooded areas and encourages the development of longer satellite wetlands estimates. C1 Columbia Univ, NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Observ Paris, CNRS, LERMA, F-75014 Paris, France. IRD, LEGOS, UMR 5566, F-31400 Toulouse, France. RP Papa, F (reprint author), Columbia Univ, NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM fpapa@giss.nasa.gov RI Papa, Fabrice/D-3695-2009; Rossow, William/F-3138-2015; DURAND, Fabien/G-4229-2016 OI Papa, Fabrice/0000-0001-6305-6253; DURAND, Fabien/0000-0001-9660-1422 NR 14 TC 31 Z9 31 U1 2 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 19 PY 2006 VL 33 IS 8 AR L08401 DI 10.1029/2006GL025767 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039LT UT WOS:000237307900006 ER PT J AU Neelin, JD Munnich, M Su, H Meyerson, JE Holloway, CE AF Neelin, JD Munnich, M Su, H Meyerson, JE Holloway, CE TI Tropical drying trends in global warming models and observations SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE climate change; tropical precipitation; drought ID SURFACE-TEMPERATURE TRENDS; TRANSIENT CLIMATE-CHANGE; EL-NINO; PRECIPITATION; VARIABILITY; CYCLE; CO2; SIMULATION; ATMOSPHERE; FREQUENCY AB Anthropogenic changes in tropical rainfall are evaluated in a multimodel ensemble of global warming simulations. Major discrepancies on the spatial distribution of these precipitation changes remain in the latest-generation models analyzed here. Despite this uncertainty, we find a number of measures, both global and local, on which reasonable agreement is obtained, notably for the regions of drying trend (negative precipitation anomalies). Models agree on the overall amplitude of the precipitation decreases that occur at the margins of the convective zones, with percent error bars of magnitude similar to those for the tropical warming. Similar agreement is found on a precipitation climate sensitivity defined here and on differential moisture increase inside and outside convection zones, a step in a hypothesized causal path leading to precipitation changes. A measure of local intermodel agreement on significant trends indicates consistent predictions for particular regions. Observed rainfall trends in several data sets show a significant summer drying trend in a main region of intermodel agreement: the Caribbean/Central-American region. C1 Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Neelin, JD (reprint author), Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA 90095 USA. EM neelin@atmos.ucla.edu RI Neelin, J. David/H-4337-2011; Holloway, Christopher/F-1629-2013 OI Holloway, Christopher/0000-0001-9903-8989 NR 34 TC 230 Z9 235 U1 5 U2 44 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD APR 18 PY 2006 VL 103 IS 16 BP 6110 EP 6115 DI 10.1073/pnas.0601798103 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 035KF UT WOS:000236999000011 PM 16606851 ER PT J AU Bilitza, D Reinisch, BW Radicella, SM Pulinets, S Gulyaeva, T Triskova, L AF Bilitza, D Reinisch, BW Radicella, SM Pulinets, S Gulyaeva, T Triskova, L TI Improvements of the International Reference Ionosphere model for the topside electron density profile SO RADIO SCIENCE LA English DT Article ID PLASMASPHERE; SOUNDER AB [ 1] Shortcomings of the representation of the topside electron density profile in the International Reference Ionosphere (IRI) model have been noted in comparison with recently analyzed topside sounder data and also with total electron content (TEC) data. Various studies have proposed corrections of the IRI formulas or have introduced a new formalism. This paper reviews the different approaches, their implications for IRI, and their current status. An important challenge for topside modeling is the truthful representation of profiles in the equatorial anomaly (EA) region over the whole range of the EA fountain. This means that the latitudinal representation has to reproduce the merging of the double- peak signature at F region heights into a single peak at the top of the fountain. In this context, special emphasis is given to the coupling between topside and plasmaspheric models. C1 NASA, Goddard Space Flight Ctr, Raytheon Intelligence & Informat Syst, Greenbelt, MD 20771 USA. Univ Massachusetts, Ctr Atmospher Res, Lowell, MA 01854 USA. Abdus Salam Int Ctr Theoret Phys, Aeron & Radiopropagat Lab, I-34014 Trieste, Italy. Univ Nacl Autonoma Mexico, Inst Geophys, Mexico City 04150, DF, Mexico. Inst Terr Magnetism Ionosphere & Radio Wave P, Moscow, Russia. Polish Acad Sci, Space Res Ctr, PL-01237 Warsaw, Poland. Acad Sci, Inst Atmospher Phys, Prague 14131 4, Czech Republic. RP Bilitza, D (reprint author), NASA, Goddard Space Flight Ctr, Raytheon Intelligence & Informat Syst, Code 612-4, Greenbelt, MD 20771 USA. EM bilitza@pop600.gsfc.nasa.gov RI Triskova, Ludmila/H-6503-2014; Pulinets, Sergey/F-7462-2011 OI Pulinets, Sergey/0000-0003-3944-6686 NR 29 TC 42 Z9 43 U1 2 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD APR 18 PY 2006 VL 41 IS 5 AR RS5S15 DI 10.1029/2005RS003370 PG 8 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 039NM UT WOS:000237312800001 ER PT J AU Chin, AH Vaddiraju, S Maslov, AV Ning, CZ Sunkara, MK Meyyappan, M AF Chin, AH Vaddiraju, S Maslov, AV Ning, CZ Sunkara, MK Meyyappan, M TI Near-infrared semiconductor subwavelength-wire lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID NANOWIRE LASER; DIAMETER SILICA; WAVE-GUIDES; MODES AB We report near-infrared lasing in the telecommunications band in gallium antimonide semiconductor subwavelength wires. Our results open the possibility of the use of semiconductor subwavelength-wire lasers in future photonic integrated circuits for telecommunications applications. (c) 2006 American Institute of Physics. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. Univ Louisville, Dept Chem Engn, Louisville, KY 40292 USA. RP Chin, AH (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM achin@mail.arc.nasa.gov; cning@mail.arc.nasa.gov RI Sunkara, Mahendra/A-3033-2008; Maslov, Alexey/E-5158-2011; Ning, C. Z./D-4699-2009 OI Maslov, Alexey/0000-0002-7835-2474; Ning, C. Z./0000-0003-4583-8889 NR 16 TC 63 Z9 65 U1 2 U2 25 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 17 PY 2006 VL 88 IS 16 AR 163115 DI 10.1063/1.2198017 PG 3 WC Physics, Applied SC Physics GA 034ZL UT WOS:000236969300098 ER PT J AU Polak, T Rock, BN Campbell, PE Soukupova, J Solcova, B Zvara, K Albrechtova, J AF Polak, T Rock, BN Campbell, PE Soukupova, J Solcova, B Zvara, K Albrechtova, J TI Shoot growth processes, assessed by bud development types, reflect Norway spruce vitality and sink prioritization SO FOREST ECOLOGY AND MANAGEMENT LA English DT Article DE tree vitality; buds; carbon allocation; sink/source concept; crown defoliation; Norway spruce (Picea abies) ID PICEA-ABIES; STRUCTURAL DEVELOPMENT; SIMULATED HERBIVORY; VEGETATIVE BUDS; CROWN CONDITION; MOUNTAIN BIRCH; FOREST DECLINE; CHLOROPHYLL-A; DOUGLAS-FIR; RED SPRUCE AB Crown defoliation, is a product of the tree crown status from the past several years of growth, which can be misleading if used as a stress indicator when assessing current Norway spruce vitality. To evaluate recovery processes in previously damaged trees a newly developed macroscopic indicator based on proportions of bud development types was investigated. In 1998 and 1999, 474 mature Norway spruce trees were sampled for macroscopic measurements, 293 trees for tree-ring increments and 40 trees for study of metabolic markers (concentration of chlorophylls, phenolic compounds and lignin). Study sites were located in the Czech Republic, in the Sumava Mts, a relatively unpolluted and undisturbed area, and in the Krusne hory Mts, which exhibited a whole range of tree damage corresponding to a gradient of increasing air pollution load. Three categories of trees were identified which reflect current levels of intensity of shoot formation and capacity to replace potential needle loss by activation of buds with growth potential: accelerated, stabilized and decreased shoot growth. Relative to sink prioritization, we concluded that the highest vitality occurred in trees with stabilized shoot growth and the lowest vitality in trees with accelerated shoot growth. In conifers, the amount of allocated assimilates to low priority carbon sinks (such as stem growth, production of protective chemical compounds and reproductive organs) depends on what is remaining from the shoot growth processes which are of the highest priority. Significant inverse relationships were found between the intensity of shoot growth, tree-ring increments, production of reproductive organs and concentration of phenolic compounds in the needles. The highest allocation of assimilates to crown recovery occurred in trees with crown defoliation of 50-69% indicating forest recovery was observed in the most heavily damaged areas impacted by air pollution in the past. The present criterion of bud development types has potential for forestry management applications as it is easily applied in the field and, in contrast with standard forestry measurement of crown defoliation, it reflects accurately tree recovery and decline processes under multiple stress impacts. (c) 2006 Elsevier B.V. All rights reserved. C1 Charles Univ, Fac Sci, Dept Plant Physiol, CZ-12844 Prague 2, Czech Republic. Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Greenbelt, MD 20771 USA. Acad Sci Czech Republ, Inst Expt Bot, CZ-16502 Prague 6, Czech Republic. Charles Univ, Fac Math & Phys, Dept Probabil & Math Stat, CZ-18675 Prague 8, Czech Republic. Acad Sci Czech Republ, Inst Bot, CZ-25243 Pruhonice, Czech Republic. RP Albrechtova, J (reprint author), Charles Univ, Fac Sci, Dept Plant Physiol, Vinicna 5, CZ-12844 Prague 2, Czech Republic. EM albrecht@natur.cuni.cz RI Campbell, Petya/A-9649-2008; Campbell, Petya/G-4931-2013; OI Campbell, Petya/0000-0002-0505-4951; Albrechtova, Jana/0000-0001-6912-1992 NR 61 TC 20 Z9 21 U1 1 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1127 J9 FOREST ECOL MANAG JI For. Ecol. Manage. PD APR 15 PY 2006 VL 225 IS 1-3 BP 337 EP 348 DI 10.1016/j.foreco.2006.01.027 PG 12 WC Forestry SC Forestry GA 031BF UT WOS:000236678400035 ER PT J AU Brandon, AD Walker, RJ Puchtel, IS AF Brandon, AD Walker, RJ Puchtel, IS TI Platinum-osmium isotope evolution of the Earth's mantle: Constraints from chondrites and Os-rich alloys SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CONVERGENT PLATE MARGIN; RE-OS; SIDEROPHILE ELEMENTS; RE-187-OS-187 SYSTEMATICS; OS-186-OS-187 SYSTEMATICS; EARLY DIFFERENTIATION; PRIMITIVE CHONDRITES; PERIDOTITE XENOLITHS; SOUTHWESTERN OREGON; ABYSSAL PERIDOTITES AB Separation of a metal-rich core strongly depleted the silicate portion of the Earth in highly siderophile elements (HSE). including Pt, Re, and Os. To address the issues of how early differentiation, partial melting, and enrichment processes may have affected the relative abundances of the HSE in the upper mantle, Os-187/Os-188 and Os-186/Os-188 data for chondrites are compared with data for Os-rich alloys from upper mantle peridotites. Given that Os-187 and Os-186 are decay products of Re-187 and Pt-190, respectively, these ratios can be used to constrain the lone-term Re/Os and Pt/Os of mantle reservoirs in comparison to chondrites. Because of isotopic homogeneity, H-group ordinary and other equilibrated chondrites may be most suitable for defining the initial Os-186/Os-188 of the solar system. The Os-186/Os-188 ratios for five H-group ordinary chondrites range only from 0.1198384 to 0.1198408, with an average of 0.1198398 +/- 0.0000016 (2 sigma). Using the measured Pt/Os and Os-186/Os-188 for each chondrite, the calculated initial Os-186/Os-188 at 4.567 Ga is 0.1198269 +/- 0.0000014 (2 sigma). This is the current best estimate for the initial Os-186/Os-188 of the bulk solar system. The mantle evolution of Os-186/ Os-188 can be defined via examination of mantle-derived materials with well-constrained ages and low Pt/Os. Two types of mantle-derived materials that can be used for this task are komatiites and Os-rich alloys. The alloys are particularly valuable in that they have little or no Re or Pt, thus, when formed, evolution of both Os-187/Os-188 and Os-186/Os-188 ceases. Previously published results for an Archean komatiite and new results for Os-rich alloys indicate that the terrestrial mantle evolved with Pt-Os isotopic systematics that were indistinguishable from the H-group ordinary and some enstatite chondrites. This corresponds to a Pt/Os of 2.0 +/- 0.2 for the primitive upper mantle evolution curve. This similarity is consistent with previous arguments, based on the Os-187/Os-188 systematics and HSE abundances in the mantle, for a late veneer of materials with chondritic bulk compositions controlling the HSE budget of the upper mantle. It is very unlikely that high pressure metal-silicate segregation leading to core formation can account for the elemental and isotopic compositions of HSE in the upper mantle. (c) 2006 Elsevier Inc. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Maryland, Isotope Geochem Lab, Dept Geol, College Pk, MD 20742 USA. RP Brandon, AD (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code KR,Bldg 31, Houston, TX 77058 USA. EM alan.d.brandon1@jsc.nasa.gov RI Walker, Richard/K-6869-2016 OI Walker, Richard/0000-0003-0348-2407 NR 58 TC 57 Z9 59 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD APR 15 PY 2006 VL 70 IS 8 BP 2093 EP 2103 DI 10.1016/j.gca.2006.01.005 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 036BH UT WOS:000237045300017 ER PT J AU Cho, JU Min, JH Ko, SP Soh, JY Kim, YK Wu, JH Choi, SH AF Cho, JU Min, JH Ko, SP Soh, JY Kim, YK Wu, JH Choi, SH TI Effect of external magnetic field on anisotropy of Co/Cu multilayer nanowires SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ANODIC ALUMINA; ARRAYS; ELECTRODEPOSITION; WIRES AB We have investigated the effect of external magnetic field exercised during the fabrication of the Co and Co/Cu multilayer nanowires in anodic aluminum oxide (AAO) templates using pulse electrodeposition. It is found that the effect becomes significant when the pore size is small. Deterioration occurs in the magnetic properties for the Co nanowires studied, whereas a distinct enhancement in the magnetic properties for the Cu/Co multilayer nanowires is achieved by applying an external magnetic field during nanowire growth using the AAO template comprising pores of 50 nm diameter. (C) 2006 American Institute of Physics. C1 Korea Univ, Dept Mat Sci & Engn, Seoul 136713, South Korea. Korea Univ, Res Inst Engn & Technol, Seoul 136713, South Korea. NASA, BioNanotechnol Grp, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kim, YK (reprint author), Korea Univ, Dept Mat Sci & Engn, Seoul 136713, South Korea. EM ykim97@korea.ac.kr RI Cho, Jiung/A-3626-2013 NR 11 TC 30 Z9 31 U1 3 U2 23 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2006 VL 99 IS 8 AR 08C909 DI 10.1063/1.2172579 PG 3 WC Physics, Applied SC Physics GA 040TV UT WOS:000237404200197 ER PT J AU Lin, CL Yuen, T Zan, JA Li, J AF Lin, CL Yuen, T Zan, JA Li, J TI Thermal and magnetic properties of La-doped Ce1-yLayGe1.80 with 0 < y < 1.0 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CRYSTAL-STRUCTURE; SUPERCONDUCTIVITY; SYSTEM; CEGE2; HEAT AB CeGex with 1.71 < x <= 2.0 crystallizes in an orthorhombic structure and exhibits two magnetic transitions: an antiferromagnetic transition at T-N=7 K and a ferromagnetic transition at T-C=4.3 K. When x decreases below 1.71, CeGex transforms to a tetragonal structure and exhibits only an antiferromagnetic transition at T-N=7 K. We have further studied the physical properties of La-doped Ce1-yLayGe1.80 with 0 < y < 1.0. The magnetization and specific-heat measurements show that with initial La substitution for Ce, T-N decreases monotonically while T-C increases slightly, and T-N and T-C merge to become a single ferromagnetic state at T-C=4.8 K in the vicinity of y=0.22. With further La doping, T-C decreases slowly and linearly from 4.8 to 1.75 K at y=0.65. The x-ray measurements show that the lattice parameters remain nearly unchanged in the two magnetic transition regimes with 0 < y < 0.22 and increase monotonically with further La substitution for Ce (0.22 < y <= 1.0). The entropy removal and magnetic moment calculations are also discussed. (C) 2006 American Institute of Physics. C1 Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Rutgers State Univ, Dept Chem & Biol Chem, Piscataway, NJ 08854 USA. RP Lin, CL (reprint author), Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. EM clin@temple.edu NR 10 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2006 VL 99 IS 8 AR 08F707 DI 10.1063/1.2167056 PG 3 WC Physics, Applied SC Physics GA 040TV UT WOS:000237404200327 ER PT J AU Pinto, NJ Perez, R Mueller, CH Theofylaktos, N Miranda, FA AF Pinto, NJ Perez, R Mueller, CH Theofylaktos, N Miranda, FA TI Dual input AND gate fabricated from a single channel poly(3-hexylthiophene) thin film field effect transistor SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CONJUGATED POLYMERS; DEVICE; POLYANILINE AB A regio-regular poly(3-hexylthiophene) (RRP3HT) thin film transistor having a split gate architecture has been fabricated on a doped silicon/silicon nitride substrate and characterized. This device demonstrates AND logic functionality. The device functionality was controlled by applying either 0 or -10 V to each of the gate electrodes. When -10 V was simultaneously applied to both gates, the device was conductive (on), while any other combination of gate voltages rendered the device resistive (off). The p-type carrier charge mobility was about 5x10(-4) cm(2)/V s. The low mobility is attributed to the sharp contours of the RRP3HT film due to substrate nonplanarity. A significant advantage of this architecture is that AND logic devices with multiple inputs can be fabricated using a single RRP3HT channel with multiple gates. (C) 2006 American Institute of Physics. C1 Univ Puerto Rico, Dept Phys & Elect, Humacao, PR 00791 USA. Analex Corp, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Pinto, NJ (reprint author), Univ Puerto Rico, Dept Phys & Elect, Humacao, PR 00791 USA. EM nj_pinto@webmail.uprh.edu NR 21 TC 7 Z9 7 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2006 VL 99 IS 8 AR 084504 DI 10.1063/1.2188131 PG 5 WC Physics, Applied SC Physics GA 040TV UT WOS:000237404200062 ER PT J AU Shull, RD Provenzano, V Shapiro, AJ Fu, A Lufaso, MW Karapetrova, J Kletetschka, G Mikula, V AF Shull, RD Provenzano, V Shapiro, AJ Fu, A Lufaso, MW Karapetrova, J Kletetschka, G Mikula, V TI The effects of small metal additions (Co, Cu, Ga, Mn, Al, Bi, Sn) on the magnetocaloric properties of the Gd5Ge2Si2 alloy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GD-5(SI2GE2) AB The structural and magnetic properties of arc-melted and homogenized (1300 degrees C, 1 h) alloys of Gd5Ge1.9Si2X0.1 (X=Cu, Co, Ga, Mn, Al, Bi, or Sn) were investigated by powder x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and magnetometry. The addition of Cu, Ga, Mn, and Al completely eliminated the large hysteresis losses present in the undoped Gd5Ge2Si2 alloy between 270 and 330 K, broadened the magnetic entropy change Delta Sm peak, and shifted its peak value from 275 to 305 K similar to that observed earlier for Gd5Ge1.9Si2Fe0.1. The addition of Bi or Sn had a negligible effect on either the alloy hysteresis losses or the characteristics of the Delta S-m vs T peak. The microstructure of the alloy doped with Cu, Co, Ga, Mn, or Al consisted of a majority phase (depleted of silicon) and a minor intergranular phase (rich in silicon and of the corresponding metal additive). For Bi or Sn doping, the microstructure consisted of only the Gd5Ge2Si2 phase. Low temperature x-ray diffraction data on an Fe-doped sample showed the same spectra at 245 and 300 K, consistent with the majority phase possessing an orthorhombic structure. Refrigeration capacity calculations show that Gd5Ge1.9Si2X0.1 (X=Fe,Cu,Co,Ga,Mn, or Al) alloys are superior magnetic refrigerants compared to the undoped Gd5Ge2Si2 alloy. (C) 2006 American Institute of Physics. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ S Carolina, Dept Biochem & Chem, Columbia, SC 29208 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Acad Sci Czech Republ, Inst Geol, Prague, Czech Republic. RP Shull, RD (reprint author), Natl Inst Stand & Technol, 100 Bur Dr, Gaithersburg, MD 20899 USA. EM robert.shull@nist.gov RI Kletetschka, Gunther/C-9996-2011; Shull, Robert/F-5971-2013; Lufaso, Michael/A-8400-2009 OI Kletetschka, Gunther/0000-0002-0645-9037; Lufaso, Michael/0000-0001-7842-6982 NR 7 TC 28 Z9 29 U1 0 U2 19 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2006 VL 99 IS 8 AR 08K908 DI 10.1063/1.2173632 PG 3 WC Physics, Applied SC Physics GA 040TV UT WOS:000237404200507 ER PT J AU Yang, SC Cai, M Kalnay, E Rienecker, M Yuan, G Toth, Z AF Yang, SC Cai, M Kalnay, E Rienecker, M Yuan, G Toth, Z TI ENSO bred vectors in coupled ocean-atmosphere general circulation models SO JOURNAL OF CLIMATE LA English DT Article ID NINO SOUTHERN OSCILLATION; PACIFIC COLD-TONGUE; ZEBIAK-CANE MODEL; EL-NINO; OPTIMAL-GROWTH; INITIAL CONDITIONS; SINGULAR VECTORS; TROPICAL OCEAN; PREDICTABILITY; DYNAMICS AB The breeding method has been implemented in the NASA Seasonal-to-Interannual Prediction Project (NSIPP) coupled general circulation model (CGCM) with the ultimate goal of improving operational seasonal to interannual climate predictions through ensemble forecasting and data assimilation. This is the first attempt to isolate the evolving ENSO instability and its corresponding global atmospheric response in a fully coupled ocean-atmosphere GCM. The results herein show that the growth rate of the coupled bred vectors (BVs) is sensitive to the ENSO phases of the evolving background flow and peaks about 3 months before an ENSO event. The structure of the dominant growing BV modes also evolves with the background ENSO and exhibits a larger amplitude in the eastern tropical Pacific, reflecting the natural dynamical sensitivity associated with the shallow thermocline at the eastern boundary. The key features of coupled bred vectors of the NSIPP CGCM are reproduced when using the NCEP CGCM, an independently developed coupled general circulation model. C1 Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. Harvard Univ, Baur Ctr Genom Res, Cambridge, MA 02138 USA. NOAA, Environm Modeling Ctr, Natl Ctr Environm Predict, Camp Springs, MD USA. RP Cai, M (reprint author), Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. EM cai@met.fsu.edu RI Kalnay, Eugenia/F-4393-2010; Toth, Zoltan/I-6624-2015; OI Toth, Zoltan/0000-0002-9635-9194; Kalnay, Eugenia/0000-0002-9984-9906 NR 47 TC 32 Z9 33 U1 2 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD APR 15 PY 2006 VL 19 IS 8 BP 1422 EP 1436 DI 10.1175/JCLI3696.1 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 038MW UT WOS:000237227000004 ER PT J AU Lau, KM Shen, SSP Kim, KM Wang, H AF Lau, KM Shen, SSP Kim, KM Wang, H TI A multimodel study of the twentieth-century simulations of Sahel drought from the 1970s to 1990s SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SEA-SURFACE TEMPERATURE; TROPICAL ATLANTIC; RAINFALL; VARIABILITY; CLIMATE; CIRCULATION; OCEAN AB [ 1] In this paper, we evaluate the performance of 19 coupled general circulation models (CGCMs) in twentieth-century simulations of the Sahel during the 1970s to 1990s. Correlation, regression, and cluster analyses are applied to observations and model outputs including Sahel monthly precipitation, evaporation, soil moisture, and sea surface temperature (SST). We find that only eight CGCMs ( hit models) produce a reasonable Sahel drought signal, while seven CGCMs ( miss models) produce excessive rainfall over the Sahel during the observed drought period. Even the model with the highest prediction skill of the Sahel drought could only predict the increasing trend of severe drought events but not the beginning and duration of the events. From analyses of the statistical characteristics of the hit and miss models, we conclude that a good simulation of the Sahel drought requires ( 1) a strong coupling between Sahel rainfall and Indian Ocean SST, with warm ( cold) SST identified with Sahel drought ( flood), ( 2) a significant coupling between Sahel rainfall and the Atlantic Ocean SST, with a warm equatorial Atlantic and cold extratropical North Atlantic coexisting with Sahel drought, and vice versa, and ( 3) a robust land surface feedback with strong sensitivity of precipitation and land evaporation to soil moisture. These three characteristics constitute sufficient conditions for a good simulation of Sahel drought in CGCMs. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Alberta, Dept Math & Stat Sci, Edmonton, AB T6G 2G1, Canada. Sci Syst & Applicat Inc, Lanham, MD USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. EM lau@climate.gsfc.nasa.gov RI Kim, Kyu-Myong/G-5398-2014; Lau, William /E-1510-2012 OI Lau, William /0000-0002-3587-3691 NR 22 TC 33 Z9 33 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 15 PY 2006 VL 111 IS D7 AR D07111 DI 10.1029/2005JD006281 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 039DR UT WOS:000237282000001 ER PT J AU Yi, J Argon, AS Sayir, A AF Yi, J Argon, AS Sayir, A TI Internal stresses and the creep resistance of the directionally solidified ceramic eutectics SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT Symposium on Internal Stress and Thermo-Mechanical Behavior in Mult-Component Materials Systems held at the TMS Annual Meeting CY MAR 14-18, 2004 CL Charlotte, NC SP TMS DE directionally solidified ceramic eutectic; creep resistance; Al2O3/c-ZrO2 eutectics ID MECHANICAL-PROPERTIES; DIFFUSIONAL CREEP; DISLOCATION CLIMB; SELF-DIFFUSION; SAPPHIRE; DEFORMATION; SIMULATIONS; ALPHA-AL2O3; COMPOSITES; ALUMINA AB The creep resistance of the directionally solidified (DS) ceramic eutectic of Al2O3/c-ZrO2(Y2O3) was studied in the temperature range of 1200-1520 degrees C. The DS eutectic morphology consists of a topologically continuous majority phase of Al2O3, with a growth texture of [0001] and an encapsulated minority c-ZrO2(Y2O3) phase in a variety of morphologies having a nearly (112) texture. The two phases are separated by well-structured but incoherent interfaces. The creep of the eutectic in its growth direction exhibits an initial transient that is attributed to stress relaxation in the c-ZrO2 phase that also allows relaxation of large initial thermal misfit stresses between phases. In steady state creep, the DS eutectic shows many of the same characteristics of creep in sapphire single crystals with c-axis orientation. The creep strain rate of the eutectic has stress exponents in the range of 4.5-5.0 and a temperature dependence suggesting a rate mechanism governed by oxygen ion diffusion in the Al2O3. A finite element analysis of distribution of internal misfit stresses and those resulting from applied stresses in the two phases, together with a detailed dislocation model of the creep rate indicate that much of the nearly nano-scale encapsulated c-ZrO2 is too small to deform by creep so that the major contribution to the recorded creep strain is derived from the diffusion-controlled climb of pyramidal edge dislocations in the Al2O3 phase. The evidence suggests that the climbing dislocations in Al2O3 must repeatly circumvent the c-ZrO2 domains acting like dispersoids resulting in the stress exponents larger than 3. The creep model is in good agreement with the experiments, and is generally supported by transmission electron microscopy (TEM) observations of dislocations in crept samples. (c) 2005 Elsevier B.V. All rights reserved. C1 MIT, Cambridge, MA 02139 USA. NASA, John Glenn Res Ctr, Cleveland, OH 44135 USA. RP Argon, AS (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM argon@mit.edu NR 33 TC 3 Z9 3 U1 2 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 15 PY 2006 VL 421 IS 1-2 SI SI BP 86 EP 102 DI 10.1016/j.msea.2005.10.012 PG 17 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 038QJ UT WOS:000237237700011 ER PT J AU Kelley, RL AF Kelley, RL TI X-ray microcalorimeters for Astro-E2 and high-energy astrophysics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE detectors; calorimeters; microcalorimeters; X-ray; spectrometer; instruments; missions ID XRS; DETECTOR AB The Japan/US Suzuku (formerly Astro-E2) astrophysics mission has been successfully launched. Suzaku is a powerful new orbiting observatory for studying extremely energetic processes in the universe. Sensitive X-ray spectrometers have been designed to enable precise measurements of high-energy processes in stars, supernova remnants, galaxies, clusters of galaxies, and the environments around neutron stars and black holes. One of the instruments is the high resolution X-ray spectrometer (XRS) that features a 32-pixel array of microcalorimeters with 6eV (FWHM) spectral resolution, the first Such device to be placed into orbit. We will describe the capabilities of the XRS instrument and present some of the very early in-flight results, which clearly show that this new technology can work extremely well in space. Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kelley, RL (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA. EM Richard.L.Kelley@nasa.gov RI Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 NR 7 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 341 EP 344 DI 10.1016/j.nima.2005.12.005 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700005 ER PT J AU Monfardini, A Arnaboldi, C Brofferio, C Capelli, S Capozzi, F Cremonesi, O Enss, C Fiorini, E Fleischmann, A Foggetta, L Gallinaro, G Gastaldo, L Gatti, F Giuliani, A Gorla, P Kelley, R Kilbourne, CA Margesin, B McCammon, D Nones, C Nucciotti, A Pavan, M Pedretti, M Pergolesi, D Pessina, G Porter, FS Prest, M Previtali, E Repetto, P Ribeiro-Gomez, M Sangiorgio, S Sisti, M AF Monfardini, A Arnaboldi, C Brofferio, C Capelli, S Capozzi, F Cremonesi, O Enss, C Fiorini, E Fleischmann, A Foggetta, L Gallinaro, G Gastaldo, L Gatti, F Giuliani, A Gorla, P Kelley, R Kilbourne, CA Margesin, B McCammon, D Nones, C Nucciotti, A Pavan, M Pedretti, M Pergolesi, D Pessina, G Porter, FS Prest, M Previtali, E Repetto, P Ribeiro-Gomez, M Sangiorgio, S Sisti, M TI The microcalorimeter arrays for a rhenium experiment (MARE): A next-generation calorimetric neutrino mass experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE neutrino mass; beta decay; thermal detectors; Re-187 AB Neutrino oscillation experiments have proved that neutrinos are massive particles, but cannot determine their absolute mass scale. Therefore the neutrino mass is still an open question in elementary particle physics. An international collaboration is growing around the project of Microcalorimeter Arrays for a Rhenium Experiment (MARE) for directly measuring the neutrino mass with a sensitivity of about 0.2eV/c(2). Many groups are joining their experiences and technical expertise in a common effort towards this challenging experiment. We discuss the different scenarios and the impact of MARE as a complement of KATRIN. (c) 2005 Elsevier B.V. All rights reserved. C1 Sez Milano, Ist Nazl Fis Nucl, I-20126 Milan, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. IRST, ITC, I-38050 Povo, TN, Italy. Ist Nazl Fis Nucl, Grp Trento, I-38050 Povo, TN, Italy. Heidelberg Univ, Kirchhoff Inst Phys, INF 227, D-69120 Heidelberg, Germany. Univ Insubria, Dipartimento Matemat & Fis, I-22100 Como, Italy. Ist Nazl Fis Nucl, Sez Milano, I-22100 Como, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, Sez Genova, I-16146 Genoa, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Nucciotti, A (reprint author), Sez Milano, Ist Nazl Fis Nucl, Piazza Sci 3, I-20126 Milan, Italy. EM ettore.fiorini@mib.infn.it; angelo.nucciotti@mib.infn.it RI Sisti, Monica/B-7550-2013; Porter, Frederick/D-3501-2012; Foggetta, Luca/A-4810-2010; Nucciotti, Angelo/I-8888-2012; Kelley, Richard/K-4474-2012; Gatti, Flavio/K-4568-2013; Gorla, Paolo/B-5243-2014; Sangiorgio, Samuele/F-4389-2014; Margesin, Benno/K-5826-2015; Pergolesi, Daniele/P-8813-2015; capelli, silvia/G-5168-2012 OI PREST, MICHELA/0000-0003-3161-4454; pavan, maura/0000-0002-9723-7834; Pessina, Gianluigi Ezio/0000-0003-3700-9757; Sisti, Monica/0000-0003-2517-1909; Porter, Frederick/0000-0002-6374-1119; Foggetta, Luca/0000-0002-6389-1280; Nucciotti, Angelo/0000-0002-8458-1556; Sangiorgio, Samuele/0000-0002-4792-7802; Margesin, Benno/0000-0002-1120-3968; Pergolesi, Daniele/0000-0002-6231-0237; capelli, silvia/0000-0002-0300-2752 NR 7 TC 33 Z9 33 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 346 EP 348 DI 10.1016/j.nima.2005.12.006 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700006 ER PT J AU Nucciotti, A Arnaboldi, C Beeman, JW Capozzi, F Ceruti, G Kilbourne, CA Kreysa, E McCammon, D Monfardini, A Pessina, G Previtali, E Sisti, M AF Nucciotti, A Arnaboldi, C Beeman, JW Capozzi, F Ceruti, G Kilbourne, CA Kreysa, E McCammon, D Monfardini, A Pessina, G Previtali, E Sisti, M TI Comparison between implanted Si and NTD-Ge thermistors performance in AgReO4 microcalorimeters for a new neutrino mass experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE microcalorimeter arrays; thermal detectors; Re-187; beta decay; neutrino mass AB We report here the preliminary results of the R&D for a new neutrino mass experiment. This experiment is prepared in the framework of the Microcalorimeters Arrays for a Rhenium Experiment (MARE) project. First tests were made on silicon implanted and germanium NTD arrays with AgReO4 crystals. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Milano Bicocca, Dipartimento Fis G Occhialini, I-20126 Milan, Italy. Univ Milano Bicocca, Ist Nazl Fis Nucl, I-20126 Milan, Italy. NASA, Goddard Space Flight Ctr, Berkeley, CA USA. Max Planck Inst Radioastron, Bonn, Germany. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. IRST, ITC, Povo, TN, Italy. Ist Nazl Fis Nucl, Grp Trento, Povo, TN, Italy. RP Nucciotti, A (reprint author), Univ Milano Bicocca, Dipartimento Fis G Occhialini, I-20126 Milan, Italy. EM angelo.nucciotti@mib.infn.it RI Nucciotti, Angelo/I-8888-2012; Sisti, Monica/B-7550-2013; OI Nucciotti, Angelo/0000-0002-8458-1556; Sisti, Monica/0000-0003-2517-1909; Pessina, Gianluigi Ezio/0000-0003-3700-9757 NR 3 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 367 EP 369 DI 10.1016/j.nima.2005.12.011 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700013 ER PT J AU Saab, T Figueroa-Feliciano, E Iyomoto, N Herbert, BD Bandler, SR Chervenak, J Finkbeiner, F Kelley, RL Kilbourne, CA Porter, FS Sadleir, J AF Saab, T Figueroa-Feliciano, E Iyomoto, N Herbert, BD Bandler, SR Chervenak, J Finkbeiner, F Kelley, RL Kilbourne, CA Porter, FS Sadleir, J TI Determination of lateral diffusivity in single pixel X-ray absorbers with implications for position dependent excess broadening SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE X-ray spectrometer; microcalorimeter; diffusivity AB An ideal microcalorimeter is characterized by a constant energy resolution across the sensor's dynamic range. Any dependence of pulse shape on the position within the absorber where an event occurs leads to a degradation in resolution that is linear with event's energy (excess broadening). In this paper we present a numerical simulation that was developed to model the variation in pulse shape with position based on the thermal conductivity within the absorber and between the absorber, sensor, and heat bath, for arbitrarily shaped absorbers and sensors. All the parameters required for the simulation can be measured from actual devices. We describe how the thermal conductivity of the absorber material is determined by comparing the results of this model with data taken from a position sensitive detector in which any position dependent effect is purposely emphasized by constructing a long, narrow absorber that is readout by sensors on both ends. Finally, we present the implications for excess broadening given the measured parameters of our X-ray microcalorimeters. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Saab, T (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM tsaab@milkyway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 1 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 426 EP 428 DI 10.1016/j.nima.2005.12.028 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700031 ER PT J AU Porter, FS Kelley, RL Kilbourne, CA AF Porter, FS Kelley, RL Kilbourne, CA TI High resolution X-ray microcalorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE X-ray; microcalorimeter; solid state detector AB Recently we have produced X-ray microcalorimeters with resolving powers approaching 2000 at 5.9 keV using a spare XRS microcalorimeter array. In these experiments, we attached 400 mu m square, 8 mu m thick HgTe absorbers using a variety of attachment methods to an XRS array and tested the detector array at temperatures between 40 and 60 mK. The best results were for absorbers attached using the standard XRS absorber-pixel thermal isolation scheme utilizing SU-8 polymer tubes. In this scenario we achieved a resolution of 3.2 eV FWHM at 5.9 keV. Substituting a silicon spacer for the SU-8 tubes also yielded sub-5eV results. In contrast, absorbers attached directly to the thermistor produced significant position dependence and thus degraded resolution. We discuss these new high resolution results, the various absorber attachment schemes, and planned future improvements. Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Porter, FS (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM frederick.s.porter@nasa.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 4 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 436 EP 438 DI 10.1016/j.nima.2005.12.030 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700034 ER PT J AU Sadleir, JE Bandler, SR Brekosky, RP Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, RL Kilbourne, CA King, JM Porter, FS Robinson, IK Saab, T Talley, DJ AF Sadleir, JE Bandler, SR Brekosky, RP Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, RL Kilbourne, CA King, JM Porter, FS Robinson, IK Saab, T Talley, DJ TI Bismuth X-ray absorber studies for TES microcalorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE diffusion; in situ resistance annealing; multilayer strip resistance; X-ray absorber; superconducting transition edge sensor (TES); microcalorimetry AB Bismuth's large atomic number and low carrier density makes it an attractive X-ray absorber material for microcalorimeters. Bismuth's long fermi wavelength and long mean free paths have motivated much interest in the fabrication of high quality bismuth films to study quantum size effects. Despite such incentives, fabrication of high quality bismuth films has proven difficult, and measured properties Of Such films are highly variable in the literature. Implementing a bismuth deposition process for TES (superconducting Transition Edge Sensor) device fabrication presents additional challenges particularly at interfaces due to the inherent granularity and surface roughness of its films, its low melting point, and its tendency to diffuse and form undesired intermetallic phases. We report observations of Bi-Cu and Bi-Au diffusion in our devices correlating with large shifts in T-c (superconducting transition temperature). Using SEM and in situ R vs T annealing experiments we have been able to Study these diffusion processes and identify their activation temperatures. (c) 2005 Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Sadleir, JE (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM sadleir@milkway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 1 TC 3 Z9 3 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 447 EP 449 DI 10.1016/j.nima.2005.12.033 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700037 ER PT J AU Rocks, L Anderson, MB Bilgri, N Brekosky, R Crowder, SG Figueroa-Feliciano, E Kelley, R Kilbourne, CA Lai, T Lindeman, MA Man, J McCammon, D Nelms, KL Porter, FS Sivananthan, S Vidugiris, G Zhao, J AF Rocks, L Anderson, MB Bilgri, N Brekosky, R Crowder, SG Figueroa-Feliciano, E Kelley, R Kilbourne, CA Lai, T Lindeman, MA Man, J McCammon, D Nelms, KL Porter, FS Sivananthan, S Vidugiris, G Zhao, J TI Thin absorbers for large-area soft X-ray microcalorimeters SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE microcalorimeters; HgTe; mercury telluride; Bi; bismuth ID BISMUTH AB The X-ray Quantum Calorimeter (XQC) sounding rocket experiment utilizes a microcalorimeter array for observing the diffuse soft X-ray background. Observations of such low surface-brightness targets require a large-area detector. We will be using an array of large absorbers. Good absorbers Must rapidly and completely thermalize photons, have small heat capacity for high stopping efficiency and have good lateral thermal transport. For observing the soft X-ray background (energies < 1 keV), the volume and heat capacity of absorber material can be kept to a minimum by making the absorbers only as thick as needed for high quantum efficiency at these low energies. These thin, large-area absorbers are not self-supporting and have poor lateral heat transport. Depositing the absorber material on a Si substrate provides Support and improves lateral thermal conduction. We present heat capacity results for thin HgTe and thin Bi, each on Si substrates. We also describe the HgTe absorber fabrication. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Illinois, Chicago, IL 60607 USA. RP Rocks, L (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. EM rocks@wisp.physics.wisc.edu RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 4 TC 0 Z9 0 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 450 EP 452 DI 10.1016/j.nima.2005.12.034 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700038 ER PT J AU Kenyon, M Day, PK Bradford, CM Bock, JJ Leduc, HG AF Kenyon, M Day, PK Bradford, CM Bock, JJ Leduc, HG TI Background-limited membrane-isolated TES bolometers for far-IR/submillimeter direct-detection spectroscopy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE transition-edge sensor; far-IR spectrometer; submillimeter spectrometer; Si3N4 thermal transport AB We fabricated and measured the thermal conductance of suspended Si3N4 beams via noise thermometry to determine whether membrane-isolation bolometers are capable of reaching a phonon noise equivalent power (NEP) of 4 x 10(-20) W/Hz(1/2). This sensitivity is necessary for the Background-Limited Infrared-Submillimeter Spectrograph (BLISS) proposed for the Japanese SPICA observatory, and adequate for NASA's SAFIR observatory, a 10-m, 4 K telescope to be deployed at L2. The dimensions of the longest thermal isolation beams we measured are 3 x 0.5 x 8300 mu m(3). We also fabricated and measured the electrical properties of superconducting molybdenum/gold transition-edge sensor (TES) bolometers with isolation beams of an identical geometry. The thermal conductance (G) values obtained from the noise thermometry and the TES bolometer data when the transition temperature (T-c) of the thermistor is 60 mK correspond to an NEP of 5 x 10(-20) W/Hz(1/2), making membrane-isolated TES bolometers a strong candidate for use on BLISS-SPICA and SAFIR. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kenyon, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM matthew.e.kenyon@jpl.nasa.gov NR 5 TC 13 Z9 13 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 456 EP 458 DI 10.1016/j.nima.2005.12.036 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700040 ER PT J AU Leduc, HG Kenyon, M Day, PK Yun, M Bock, JJ AF Leduc, HG Kenyon, M Day, PK Yun, M Bock, JJ TI Fabrication of antenna-coupled transition edge sensors for polarimeter applications SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE detector; bolometer; polarimeters; superconductor; CMB AB In this paper we describe the progress in the development of polarization sensitive superconducting, bolometric detector arrays targeted at cosmic microwave background (CMB) studies. Our implementation takes advantage of superconducting technology to reduce the complexity of the typical CMB bolometer focal plane by incorporating as many of the required elements as necessary oil the detector itself. Each pixel in the array consists of a distributed dual-polarization beam forming antenna, a band pass filter, and power splitter/combiner delivering detected power to four separate superconducting transition edge sensors. This combination of elements detects the polarization of the incoming light uniquely while eliminating a large part of the cooled mass of the focal plane including feed horns, polarizers, and band pass filters. Of course this increases the fabrication complexity of the bolometric detector itself over previous implementations. We will describe our fabrication process consisting of eight front side mask levels and one back side layer designed to produce whole wafer array tiles suitable for CMB polarimeters. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Pittsburgh, EE Dept, Pittsburgh, PA 15260 USA. RP Leduc, HG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rleduc@jpl.nasa.gov NR 4 TC 2 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 459 EP 461 DI 10.1016/j.nima.2005.12.037 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700041 ER PT J AU Yun, M Bock, J Keynon, M Kuo, CL Leduc, H Turner, A Kim, MJ AF Yun, M Bock, J Keynon, M Kuo, CL Leduc, H Turner, A Kim, MJ TI Fabrication of superconducting transition edge sensor based on Mo and Au bilayers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE TES; bilayers; CMB AB We report fabricated antenna-coupled superconducting transition edge sensor (TES) for millimeter-wave polarimetry. Superconducting microwave components for an antenna-coupled focal plane will be described in this work. We use low-loss Nb/SiO/Nb transmission line as base materials as a start, although changes in the dielectric may be possible to reduce loss further. Additionally, we have fabricated single- and double-element antennas, filters and detectors. We use TES bilayers consisting of Mo/Au thin films and Nb electrical contacts on a low-stress Si3N4 membrane. In this work, we report transition temperature as a function of Mo thicknesses and Au film composition. (c) 2006 Elsevier B.V. All rights reserved. C1 Univ Pittsburgh, Dept Elect & Comp Engn, Pittsburgh, PA 15261 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Texas, Dept Elect Engn, Richardson, TX 75083 USA. RP Yun, M (reprint author), Univ Pittsburgh, Dept Elect & Comp Engn, Pittsburgh, PA 15261 USA. EM yunmh@engr.pitt.edu RI Kim, Moon/A-2297-2010 NR 9 TC 3 Z9 4 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 462 EP 464 DI 10.1016/j.nima.2006.02.041 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700042 ER PT J AU Iyomoto, N Bandler, SR Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Kelley, RL Kilbourne, CA Lindeman, MA Murphy, K Porter, FS Saab, T Sadleir, JE Talley, DJ AF Iyomoto, N Bandler, SR Brekosky, RP Chervenak, JA Figueroa-Feliciano, E Finkbeiner, FM Kelley, RL Kilbourne, CA Lindeman, MA Murphy, K Porter, FS Saab, T Sadleir, JE Talley, DJ TI Position-sensitive transition-edge sensors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE microcalorimeters; TESs (transition edge sensors); position sensitive detectors; multi-pixel detectors; X-ray AB We report the latest results from Our development of Position-Sensitive Transition-edge sensors (PoSTs), which are one-dimensional imaging spectrometers. In PoSTs with segmented Au absorbers, we obtained 8 eV energy resolution oil K K alpha lines, which is consistent to the baseline energy resolution and the design values, on all of the nine pixels, by choosing the best combination of the thermal conductance in absorbers and in links that connects the absorbers. The pulse decay time of 193 mu s is fast enough for our purpose. In a PoST with a continuous Bi/Cu absorber, by dividing the events into 63 effective pixels, we obtained energy resolutions of 16eV at the center "pixel", which is comparable to the baseline energy resolution, and 33 eV at the outer "pixel". The degradation of the energy resolution in the outer "pixel" is due to position dependence, which we call cancel out by dividing the events into smaller "pixels" when we have sufficient X-ray events. (c) 2005 Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Iyomoto, N (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM iyomoto@milkyway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 3 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 491 EP 493 DI 10.1016/j.nima.2005.12.082 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700051 ER PT J AU Allen, CA Benford, DJ Chervenak, JA Chuss, DT Miller, TM Moseley, SH Staguhn, JG Wollack, EJ AF Allen, CA Benford, DJ Chervenak, JA Chuss, DT Miller, TM Moseley, SH Staguhn, JG Wollack, EJ TI Backshort-Under-Grid arrays for infrared astronomy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE Backshort-Under-Grid; transition edge sensors; bolometer; large format arrays; indium bump bonding AB We are developing a kilopixel, filled bolometer array for space infrared astronomy. The array consists of three individual components, to be merged into a single, working unit; (1) a transition edge sensor bolometer array, operating in the milliKelvin regime, (2) a quarter-wave backshort grid, and (3) superconducting quantum interference device Multiplexer readout. The detector array is designed as a filled, square grid of suspended, silicon bolometers with superconducting sensors. The backshort arrays are fabricated separately and will be positioned in the cavities created behind each detector during fabrication. The grids have a unique interlocking feature machined into the walls for positioning and mechanical stability. The spacing of the backshort beneath the detector grid can be set from similar to 30-300 mu m, by independently adjusting two process parameters during fabrication. The ultimate goal is to develop a large-format array architecture with background-limited sensitivity, suitable for a wide range of wavelengths and applications, to be directly bump bonded to a multiplexer circuit. We have produced prototype two-dimensional arrays having 8 x 8 detector elements. We present detector design, fabrication overview, and assembly technologies. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. QSS Grp Inc, Lanham, MD 20706 USA. RP Allen, CA (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM christine.allen@nasa.gov RI Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012; Chuss, David/D-8281-2012; Wollack, Edward/D-4467-2012 OI Benford, Dominic/0000-0002-9884-4206; Wollack, Edward/0000-0002-7567-4451 NR 3 TC 20 Z9 20 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 522 EP 524 DI 10.1016/j.nima.2005.12.059 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700061 ER PT J AU Figueroa-Feliciano, E Bandler, SR Chervenak, J Finkbeiner, F Moto, NY Kelley, RL Kilbourne, CA Porter, FS Saab, T Sadleir, J White, J AF Figueroa-Feliciano, E Bandler, SR Chervenak, J Finkbeiner, F Moto, NY Kelley, RL Kilbourne, CA Porter, FS Saab, T Sadleir, J White, J TI Design and performance of large-pixel-size high-fill-fraction TES arrays for future X-ray astrophysics missions SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE TES; absorbers; arrays; large-pixel; diffusion; position dependence AB We have designed, modeled, fabricated and tested a 600 pm high-fill-fraction microcalorimeter array that will be a good match to the requirements of future X-ray missions. Our devices use transition-edge sensors coupled to overhanging bismuth/copper absorbers to produce arrays with 97% or higher fill fraction. An extensive modeling effort was undertaken in order to accommodate large pixel sizes (500-1000 mu m) and maintain the best energy resolution possible. The finite thermalization time of the large absorber and the associated position dependence of the pulse shape on absorption position constrain the time constants of the system given a desired energy-resolution performance. We show the results of our analysis and our new pixel design, consisting of a novel TES-on-the-side architecture which creates a controllable TES-absorber conductance. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Figueroa-Feliciano, E (reprint author), MIT, Dept Phys, Bld 37-664C, Cambridge, MA 02139 USA. EM enectali@mit.edu RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 1 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 528 EP 530 DI 10.1016/j.nima.2005.12.203 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700063 ER PT J AU Staguhn, JG Allen, CA Benford, DJ Chervenak, JA Chuss, DT Miller, TM Moseley, SH Wollack, EJ AF Staguhn, JG Allen, CA Benford, DJ Chervenak, JA Chuss, DT Miller, TM Moseley, SH Wollack, EJ TI Characterization of TES bolometers used in 2-dimensional Backshort-Under-Grid (BUG) arrays for far-infrared astronomy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE bolometers; transition edge sensor; superconductor; fundamental noise AB We have produced a laboratory demonstration of our new Backshort-Under-Grid (BUG) bolometer array architecture in a monolithic, 2-dimensional, 8 x 8 format. The detector array is designed as a square grid of suspended, 1 mu m thick silicon bolometers with superconducting molybdium/gold bilayer TESs. These detectors use an additional layer of gold bars deposited on top of the bilayer, oriented transverse to the direction of the current flow, for the suppression of excess noise. This detector design has earlier been shown to provide near fundamental noise limited device performance. We present results from performance measurements of witness devices. In particular we demonstrate that the inband excess noise level of the TES detectors is less than 20% above the thermodynamic phonon noise limit and not significantly higher out of band at frequencies that cannot be attenuated by the Nyquist filter. Our 8 x 8 BUG arrays will be used in the near future for astronomical observations in several (sub-)millimeter instruments. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SSAI, Lanham, MD 20706 USA. QSS, Lanham, MD 20706 USA. RP Staguhn, JG (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM johannes.staguhn@gsfc.nasa.gov RI Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012; Chuss, David/D-8281-2012; Wollack, Edward/D-4467-2012 OI Benford, Dominic/0000-0002-9884-4206; Wollack, Edward/0000-0002-7567-4451 NR 3 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 545 EP 547 DI 10.1016/j.nima.2005.12.066 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700069 ER PT J AU Miller, TM Abrahams, JH Allen, CA AF Miller, TM Abrahams, JH Allen, CA TI Fabricating interlocking support walls, with an adjustable backshort, in a TES bolometer array for far-infrared astronomy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE 3D micro-machining; Gray-scale lithography; detector fabrication; infrared astronomy AB We report a fabrication process for deep etching silicon to different depths with a single masking layer, using standard masking and exposure techniques. Using this technique, we have incorporated a deep notch in the support walls of a transition-edge-sensor (TES) bolometer array during the detector back-etch, while simultaneously creating a cavity behind the detector. The notches serve to receive the support beams of a separate component, the Backshort-Under-Grid (BUG), an array of adjustable height quarter-wave backshorts that fill the cavities behind each pixel in the detector array. The backshort spacing, set prior to securing to the detector array, can be controlled from 25 to 300 pin by adjusting only a few process steps. In addition to backshort spacing, the interlocking beams and notches provide positioning and structural support for the similar to 1 mm pitch, 8 x 8 array. This process is being incorporated into developing a TES bolometer array with ail adjustable backshort for use in far-infrared astronomy. The masking technique and machining process used to fabricate the interlocking walls will be discussed. (c) 2005 Elsevier B.V. All rights reserved. C1 QSS Grp Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Detector Syst Branch, Greenbelt, MD 20771 USA. RP Allen, CA (reprint author), QSS Grp Inc, 4500 Forbes Blvd,Suite 200, Lanham, MD 20706 USA. EM callen@pop500.gsfc.nasa.gov NR 3 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 548 EP 550 DI 10.1016/j.nima.2005.12.067 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700070 ER PT J AU Marriage, TA Chervenak, JA Doriese, WB AF Marriage, TA Chervenak, JA Doriese, WB TI Testing and assembly of the detectors for the Millimeter Bolometer Array Camera on ACT SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE cosmology; Millimeter Wave Detector; Transition Edge Sensor; large array ID FABRICATION AB The Millimeter Bolometer Array Camera (MBAC) for the Atacama Cosmology Telescope consists of three Transition Edge Sensor (TES) arrays to make simultaneous observations of the Cosmic Microwave Background in three frequency bands. MBAC TESs are NASA Goddard Pop-Up Detectors (PUD) which are read-out by NIST time-domain multiplexers. MBAC is constructed by stacking I x 32 TES columns to form the 32 x 32 element arrays. The arrays are modular (connectorized) at the 1 x 32 column level such that array assembly is reversible and camera repair possible. Prior to assembly, each column is tested in a quick (2h) cyclin g He-4/He-3 adsorption refrigerator. Tests include measurements of TES current-voltage curves and TES complex impedance. (c) 2005 Elsevier B.V. All rights reserved. C1 Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Inst Stand, Boulder, CO 80305 USA. RP Marriage, TA (reprint author), Princeton Univ, Dept Phys, Washington Rd, Princeton, NJ 08544 USA. EM marriage@princeton.edu NR 6 TC 12 Z9 12 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 551 EP 553 DI 10.1016/j.nima.2005.12.068 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700071 ER PT J AU Day, PK Leduc, HG Goldin, A Vayonakis, T Mazin, BA Kumar, S Gao, J Zmuidzinas, J AF Day, PK Leduc, HG Goldin, A Vayonakis, T Mazin, BA Kumar, S Gao, J Zmuidzinas, J TI Antenna-coupled microwave kinetic inductance detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE kinetic inductance; submillimeter antenna; detector ID ARRAYS AB We report on the development of Microwave Kinetic Inductance Detectors (MKIDs) coupled to planar antennas for millimeter/submillimeter wavelengths. The MKID is a relatively new type of superconducting photon detector which is applicable from millimeter-wave frequencies to X-rays. Photons are absorbed in a superconductor, producing quasiparticle excitations, which change the surface reactance (kinetic inductance) of the superconductor. The changes in kinetic inductance are monitored using microwave high-Q thin-film superconducting resonators. Because the MKID is particularly amenable to frequency-domain multiplexing, with likely detector multiplexing factors of similar to 10(3) or more per cryogenic amplifier, these detectors are well suited for use in large arrays. We have fabricated MKIDs coupled to submillimeter slot-array antennas using microstrip lines and have detected power from a thermal radiation source. We discuss the potential of antenna-coupled MKID arrays for ground and space-based millimeter/submillimeter imaging. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. RP Day, PK (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Peter.K.Day@jpl.nasa.gov RI Mazin, Ben/B-8704-2011 OI Mazin, Ben/0000-0003-0526-1114 NR 4 TC 23 Z9 23 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 561 EP 563 DI 10.1016/j.nima.2005.12.057 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700074 ER PT J AU Gao, J Zmuidzinas, J Mazin, BA Day, PK Leduc, HG AF Gao, J Zmuidzinas, J Mazin, BA Day, PK Leduc, HG TI Experimental study of the kinetic inductance fraction of superconducting coplanar waveguide SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE kinetic inductance; coplanar waveguide AB We have studied the kinetic inductance fraction (ratio of kinetic inductance to total inductance) of superconducting coplanar waveguides (CPWs) by measuring the resonance frequency of CPW transmission line resonators. We describe a procedure for accurately determining the kinetic inductance of transmission line geometries with small kinetic inductance fractions. In this approach, we compare the temperature dependence of the resonance frequency with that of a resonator of the same film thickness but with a large kinetic inductance fraction. We present data for 200 nm-thick Al CPWs of several geometries and compare that with our own calculations and with calculations found in literature. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Pasadena, CA 91125 USA. Jet Propuls Lab, Pasadena, CA 91107 USA. RP Gao, J (reprint author), CALTECH, Pasadena, CA 91125 USA. EM jgao@ist.caltech.edu RI Mazin, Ben/B-8704-2011 OI Mazin, Ben/0000-0003-0526-1114 NR 5 TC 17 Z9 17 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 585 EP 587 DI 10.1016/j.nima.2005.12.075 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700082 ER PT J AU Piat, M Torre, JP Breelle, E Coulais, A Woodcraft, A Holmes, W Sudiwala, R AF Piat, M Torre, JP Breelle, E Coulais, A Woodcraft, A Holmes, W Sudiwala, R TI Modeling of Planck-high frequency instrument bolometers using non-linear effects in the thermometers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE spider web bolometer; planck HFI; electrical field effect; electron-phonon decoupling effect ID GE AB The Planck satellite, which is planned to be launched in 2007, is dedicated to surveying the Cosmic Microwave Background (CMB) to a high precision. Aboard this mission, the High-Frequency Instrument (HFI) will use 52 NTD Ge spiderweb bolometers made by Caltech-JPL and cooled to 100mK by a dilution cooler. In this paper, we present a model of these detectors that includes non-linear effects seen in NTD Ge thermometers: electron-phonon decoupling and electrical field effect. We show that this model leads to consider only electrical field effect. Furthermore, the optical characterization of the HFI bolometers clearly shows a non-ideal behavior that is explained by non-linear effects in the thermometer. We finally show that these effects have to be taken into account for optimized CMB observations and to fully understand the physics of semi-conducting bolometers. (c) 2005 Elsevier B.V. All rights reserved. C1 Coll France, AstroParticle & Cosmol, F-75231 Paris, France. Serv Aeron, F-91371 Verrieres Le Buisson, France. LERMA, Observ Paris, F-75014 Paris, France. Univ Cardiff Wales, Sch Phys & Astron, Cardiff CF24 3YB, S Glam, Wales. Jet Prop Lab, Pasadena, CA 91109 USA. RP Piat, M (reprint author), Coll France, AstroParticle & Cosmol, 11 Pl Marcelin Berthelot, F-75231 Paris, France. NR 6 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 588 EP 590 DI 10.1016/j.nima.2005.12.076 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700083 ER PT J AU Stevenson, TR Hsieh, WT Mitchell, RR Isenberg, HD Stahle, CM Cao, NT Schneider, G Travers, DE Moseley, SH Wollack, EJ Henry, RM AF Stevenson, TR Hsieh, WT Mitchell, RR Isenberg, HD Stahle, CM Cao, NT Schneider, G Travers, DE Moseley, SH Wollack, EJ Henry, RM TI Silicon hot-electron bolometers with single-electron transistor readout SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE thermistor; variable range hopping; Coulomb gap; terahertz; microcalorimeter; antenna-coupled detectors ID HOPPING CONDUCTION AB With the goal of making high-sensitivity bolometers for low-background measurements in the far-infrared or submillimeter, we have made small silicon thermistors, which act as hot-electron bolometers, with integrated single-electron transistors for readout amplifiers. Semiconductors doped just below a metal-insulator transition can make highly sensitive thermistors that have been used as thermometers in X-ray microcalorimeters and FIR bolometer arrays. In such arrays, thermal isolation is engineered by supporting the absorber and thermometer on a membrane. However, electron-phonon decoupling in doped silicon can be made the dominant thermal isolation by reducing device volume, potentially allowing a smaller thermal conductance and a more sensitive bolometer. A key feature is that, while its DC resistance is very high, the thermistor's surface impedance at terahertz frequencies is conveniently low, making feasible efficient antenna coupling of radiation into the electron system. Radio-frequency single-electron transistors integrated with the thermistors have sufficiently low input capacitance to offer high-speed readout of the high impedance detectors. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Detector Syst Branch, Greenbelt, MD 20771 USA. Muniz Engn Inc, Greenbelt, MD USA. NASA, Goddard Space Flight Ctr, Lab Observat Cosmol, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Opt Branch, Greenbelt, MD 20771 USA. RP Stevenson, TR (reprint author), NASA, Goddard Space Flight Ctr, Detector Syst Branch, Code 553, Greenbelt, MD 20771 USA. EM Thomas.R.Stevenson@nasa.gov RI Wollack, Edward/D-4467-2012 OI Wollack, Edward/0000-0002-7567-4451 NR 10 TC 2 Z9 2 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 591 EP 593 DI 10.1016/j.nima.2005.12.077 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700084 ER PT J AU Staguhn, JG Benford, DJ Moseley, SH Allen, CA Kennedy, CR Lefranc, S Maher, SF Pajot, F Rioux, C Shafer, RA Voellmer, GM AF Staguhn, JG Benford, DJ Moseley, SH Allen, CA Kennedy, CR Lefranc, S Maher, SF Pajot, F Rioux, C Shafer, RA Voellmer, GM TI First astronomical images obtained with an array of multiplexed superconducting bolometers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE bolometers; detectors; multiplexers; sub-mm instruments; spectrometers AB We present multicolor images of Jupiter observed in the 350 mu m band with the first deployed astronomical instrument to use multiplexed superconducting bolometers. The Fabry-Perot Interferometer Bolometer Research Experiment (FIBRE) is a broadband submillimeter spectrometer that made these images in July 2004 at the Caltech Submillimeter Observatory (CSO). FIBREs detectors are superconducting bilayer transition edge sensor (TES) bolometers read out by a SQUID multiplexer. An order-sorted Fabry-Perot provides illumination of a 16-element linear bolometer array, resulting in five orders at a spectral resolution R of 1200 covering a band of of the observed wavelength. The optics permit these orders to be scanned to cover the entirety of either the 350 or 450 mu m bands. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SSAI, Lanham, MD 20706 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Inst Astrophys Spatiale, Orsay, France. RP Staguhn, JG (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM johannes.staguhn@gsfc.nasa.gov RI Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012 OI Benford, Dominic/0000-0002-9884-4206; NR 5 TC 1 Z9 1 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 602 EP 604 DI 10.1016/j.nima.2005.12.087 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700087 ER PT J AU Kuo, CL Ade, P Bock, JJ Day, P Goldin, A Golwala, S Halpern, M Hilton, G Holmes, W Hristov, V Irwin, K Jones, WC Kenyon, M Lange, AE LeDuc, HG MacTavish, C Montroy, T Netterfield, CB Rossinot, P Ruhl, J Vayonakis, A Wang, G Yun, M Zmuidzinas, J AF Kuo, CL Ade, P Bock, JJ Day, P Goldin, A Golwala, S Halpern, M Hilton, G Holmes, W Hristov, V Irwin, K Jones, WC Kenyon, M Lange, AE LeDuc, HG MacTavish, C Montroy, T Netterfield, CB Rossinot, P Ruhl, J Vayonakis, A Wang, G Yun, M Zmuidzinas, J TI Antenna-coupled TES bolometers for the SPIDER experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE cosmology; TES bolometers; polarization AB SPIDER is a proposed balloon-borne experiment designed to search for the imprints of gravity waves on the polarization of the cosmic microwave background radiation. The required wide frequency coverage. large number of sensitive detectors, and the stringent power constraints on a balloon are made possible by antenna-coupled TES bolometers. Several prototype devices have been fabricated and optically characterized. Their spectral and angular responses agree well with the theoretical expectations. (c) 2006 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. Univ Wales Coll Cardiff, Cardiff CF24 3YB, S Glam, Wales. Univ British Columbia, Vancouver, BC V6T 1Z4, Canada. Natl Inst Stand & Technol, Boulder, CO USA. Univ Toronto, Toronto, ON M5S 1A7, Canada. Case Western Reserve Univ, Cleveland, OH 44106 USA. Univ Pittsburgh, Pittsburgh, PA 15261 USA. RP Kuo, CL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM clkuo@astro.caltech.edu NR 3 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 608 EP 610 DI 10.1016/j.nima.2005.12.092 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700089 ER PT J AU Stevenson, TR Hsieh, WT Schneider, G Travers, D Cao, N Wollack, E Limon, M Kogut, A AF Stevenson, TR Hsieh, WT Schneider, G Travers, D Cao, N Wollack, E Limon, M Kogut, A TI Building blocks for a polarimeter-on-a-chip SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE platelet feed horn; cosmic microwave background; thin-film microstrip; transmission lines; ortho-mode transducer; planar antenna AB For the "Primordial Anisotropy Polarization Pathfinder Array (PAPPA)" balloon flight project, we have designed and made thin-film niobium microstrip circuits as building blocks for a "polarimeter-on-a-chip" in which superconducting transmission lines are used to couple millimeter wave signals from planar antennas to superconducting transition edge sensor (TES) detectors. Our goal is to demonstrate technology for precision measurements of the polarization of the cosmic microwave background. To enable characterization and verification of our microstrip components, we have incorporated waveguide probes on each chip that can bring millimeter wave signals from a room temperature vector network analyzer to the Superconducting circuits on the chip and back again for S-parameter measurements. We have designed a planar antenna and RF choke on the probes to efficiently couple radiation between waveguide and thin-film microstrip. To support the probe antennas in waveguides, we sculpted thin silicon cantilevers that extend from an edge of each silicon chip into a pair of waveguides within a specially designed split-block mount. This technique will allow us to make calibrated measurements at low temperatures of the velocity, impedance, and loss properties of our niobium transmission lines, the frequency response of microstrip filters, hybrid Couplers, or terminations, and the performance of integrated detectors. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Stevenson, TR (reprint author), NASA, Goddard Space Flight Ctr, Code 553, Greenbelt, MD 20771 USA. EM Thomas.R.Stevenson@nasa.gov RI Wollack, Edward/D-4467-2012; OI Wollack, Edward/0000-0002-7567-4451; Limon, Michele/0000-0002-5900-2698 NR 2 TC 1 Z9 1 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 611 EP 613 DI 10.1016/j.nima.2005.12.095 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700090 ER PT J AU Ota, N Boyce, KR Brown, GV Cottam, J Fujimoto, R Furusho, T Ishisaki, Y Kelley, RL Kilbourne, CA McCammon, D Mitsuda, K Morita, U Porter, FS Takei, Y Yamamoto, M AF Ota, N Boyce, KR Brown, GV Cottam, J Fujimoto, R Furusho, T Ishisaki, Y Kelley, RL Kilbourne, CA McCammon, D Mitsuda, K Morita, U Porter, FS Takei, Y Yamamoto, M TI Performance verification of the Suzaku X-ray spectrometer in the flight configuration SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE X-ray detectors; X-ray spectrometers; microcalorimeters ID ASTRO-E2 AB The X-ray Spectrometer (XRS) is a high resolution, non-dispersive cryogenic detector on board the X-ray satellite, Suzaku (Astro-E2), which was successfully launched on July 10, 2005. The XRS achieves an energy resolution of 6eV at 6keV (FWHM) and covers a broad energy range of similar to 0.07-10keV. The XRS will enable powerful plasma diagnostics of a variety of astrophysical objects such as the dynamics of gas in clusters of galaxies. The XRS was integrated to the spacecraft in September 2004, and underwent a series of spacecraft tests until April 2005. We describe results of the XRS performance verification in the spacecraft configuration. First, the noise level was extremely low on the spacecraft, and most of the pixels achieved an energy resolution of 5-6 eV at 5.9 keV. Microphonic noise from the mechanical cooler was one of the concerns, but this was not a problem, when the dewar was integrated to the spacecraft and filled with solid neon. To attain the best energy resolution, however, correction of gain drift is mandatory. The XRS has a dedicated calibration pixel for that purpose, and drift correction using the calibration pixel is very effective when the gain variation is due to changes in the similar to 60 mK heat sink temperature. On the other hand, the calibration pixel and the other pixels do not respond in the same way to variations of the helium and neon bath temperatures, and this effect requires further Study. (c) 2006 Elsevier B.V. All rights reserved. C1 RIKEN, Wako, Saitama 3510198, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. LLNL, Livermore, CA 94550 USA. JAXA, ISAS, Sagamihara, Kanagawa 2298510, Japan. Tokyo Metropolitan Univ, Hachioji, Tokyo 1920397, Japan. Univ Wisconsin, Madison, WI 53706 USA. Miyazaki Univ, Miyazaki 8892192, Japan. RP Ota, N (reprint author), RIKEN, 2-1 Hirosawa, Wako, Saitama 3510198, Japan. EM ota@crab.riken.jp RI Mitsuda, Kazuhisa/C-2649-2008; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 3 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 614 EP 616 DI 10.1016/j.nima.2005.12.100 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700091 ER PT J AU Cottam, J Boyce, KR Brown, GV Fujimoto, R Furusho, T Ishisaki, Y Kelley, RL Kilbourne, CA McCammon, D Mitsuda, K Morita, U Ota, N Porter, FS Saab, T Takei, Y Yamamoto, M AF Cottam, J Boyce, KR Brown, GV Fujimoto, R Furusho, T Ishisaki, Y Kelley, RL Kilbourne, CA McCammon, D Mitsuda, K Morita, U Ota, N Porter, FS Saab, T Takei, Y Yamamoto, M TI Ground calibration of the XRS microcalorimeter onboard Suzaku SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE X-ray detectors; X-ray spectrometers; microcalorimeters AB The XRS microcalorimeter was launched in July 2005 as part of the Suzaku mission. It covers the energy band from 0.3 to 10 keV with a nearly constant energy resolution of 6eV and a peak effective area of 200cm(2) at 1.5keV. The XRS will provide unprecedented throughput and resolving power, particularly at high energies and for extended sources. The XRS has undergone extensive instrument level ground calibration prior to integration into the spacecraft. In this presentation, we will describe our pre-launch characterization of the instrument. We will include discussions of the energy scale, the line spread function, and the efficiency of the various components that make up the effective area. Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Inst Space & Astronaut Sci, JAXA, Sagamihara, Kanagawa 2298510, Japan. Tokyo Metropolitan Univ, Hachioji, Tokyo 1920397, Japan. Univ Wisconsin, Madison, WI 53706 USA. RIKEN, Wako, Saitama 3510198, Japan. Miyazaki Univ, Kibanadai Nish, Miyazaki 8892192, Japan. RP Cottam, J (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM jcottam@milkyway.gsfc.nasa.gov RI Mitsuda, Kazuhisa/C-2649-2008; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 617 EP 619 DI 10.1016/j.nima.2005.12.113 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700092 ER PT J AU Kilbourne, CA Boyce, KR Brown, GV Cottam, J Figueroa-Feliciano, E Fujimoto, R Furusho, T Ishisaki, Y Kelley, RL McCammon, D Mitsuda, K Morita, U Porter, FS Ota, N Saab, T Takei, Y Yamamoto, M AF Kilbourne, CA Boyce, KR Brown, GV Cottam, J Figueroa-Feliciano, E Fujimoto, R Furusho, T Ishisaki, Y Kelley, RL McCammon, D Mitsuda, K Morita, U Porter, FS Ota, N Saab, T Takei, Y Yamamoto, M TI Analysis of the Suzaku/XRS background SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE microcalorimeter array; cosmic rays; thermal detectors; X-ray detectors; electron loss AB Background counts on the XRS calorimeter spectrometer of the Suzaku Observatory (formerly Astro-E2) have several sources, including primary cosmic rays and secondary particles interacting with the pixels and with the silicon structure of the array. Using ground data, we identified the types of correlations between events on different pixels, and between pixel pulses and the signal from the anti-coincidence detector behind the calorimeter. In this paper, we present details of the ground background events and the rejection criteria required to remove them while minimizing deadtime. We also present the in-orbit background measured during the time that XRS was functioning in orbit. Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. LLNL, Livermore, CA 94550 USA. JAXA, ISAS, Sagamihara, Kanagawa 2298510, Japan. Tokyo Metropolitan Univ, Hachioji, Tokyo 1920397, Japan. Univ Wisconsin, Madison, WI 53706 USA. RIKEN, Wako, Saitama 3510198, Japan. Miyazaki Univ, Kibanadai Nish, Miyazaki 8892192, Japan. RP Kilbourne, CA (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 662, Greenbelt, MD 20771 USA. EM CAK@milkyway.gsfc.nasa.gov RI Mitsuda, Kazuhisa/C-2649-2008; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 3 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 620 EP 622 DI 10.1016/j.nima.2005.12.116 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700093 ER PT J AU Brown, GV Beiersdorfer, P Boyce, KR Chen, H Gu, MF Kahn, SM Kelley, RL Kilbourne, CA May, M Porter, FS Szymkowiak, AE Thorn, D Widmann, K AF Brown, GV Beiersdorfer, P Boyce, KR Chen, H Gu, MF Kahn, SM Kelley, RL Kilbourne, CA May, M Porter, FS Szymkowiak, AE Thorn, D Widmann, K TI Astrophysics and atomic physics using the NASA/GSFC microcalorimeter spectrometers at the LLNL electron beam ion trap and radiation properties facility SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE atomic data; instrumentation; detectors; spectrographs; X-rays; general ID CROSS-SECTIONS; EMISSION; FE23+ AB The 32 pixel laboratory microcalorimeter spectrometer built by the NASA/Goddard Space Flight Center (GSFC) is now all integral part of the spectroscopy Suite used routinely by the electron beam ion trap and radiative properties group at the Lawrence Livermore National Laboratory. The second generation laboratory instrument, dubbed the XRS/EBIT, is nearly identical to the XRS instrument on the Suzaku X-ray Observatory, formerly Astro-E2. The detector array is from the same processed wafer and uses the same HgTe absorbers. It is being used to measure the photon emission from a variety of radiation sources. These include X-ray emission from laboratory Simulated celestial sources, X-ray emission from highly charged ions of Au, and X-ray emission following charge exchange and radiative electron capture. The wide range of applications demonstrates the versatility of a high-resolution, high-efficiency low-temperature detector that is able to collect data continually with minimal operator servicing. (c) 2006 Elsevier B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, High Energy Dens & Astrophy Div, Livermore, CA 94551 USA. NASA, Goddard Space Flight Ctr, Lab Xray Astrophys, Greenbelt, MD 20770 USA. Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94309 USA. Yale Univ, New Haven, CT 06511 USA. RP Brown, GV (reprint author), Lawrence Livermore Natl Lab, High Energy Dens & Astrophy Div, 7000 E Ave, Livermore, CA 94551 USA. EM gregbrown@llnl.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 9 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 623 EP 625 DI 10.1016/j.nima.2005.12.204 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700094 ER PT J AU Nguyen, H Bradford, CM Ade, PAR Aguirre, J Battle, J Bock, J Dragovan, M Duband, L Earle, L Glenn, J Hirstov, V Matsuhara, H Naylor, B Zmuidinas, J AF Nguyen, H Bradford, CM Ade, PAR Aguirre, J Battle, J Bock, J Dragovan, M Duband, L Earle, L Glenn, J Hirstov, V Matsuhara, H Naylor, B Zmuidinas, J TI Z-spec's first light at the Caltech submillimeter observatory SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE submm/mm spectroscopy; galaxies; astrophysics ID SPECTROMETER AB We report the success of our first engineering run with Z-Spec, a new millimeter spectrograph on the 10m Caltech Submillimeter Telescope during the first week of June 2005. The bolometric instrument is indeed the first of its kind.. covering the atmospheric window from 187 to 310GHz at the spectral resolution of 250-400, and will provide a critical follow-up study for discoveries by SCUBA and Bolocam. We present the spectrum of an ultra-luminous infrared galaxy NGG 6240 obtained by Z-Spec. Z-Spec serves as a prototype for future far-IR spectrometers on a cold space telescope where large gains in sensitivity are expected. (c) 2006 Published by Elsevier B.V. C1 Jet Propuls Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. Univ Colorado, Boulder, CO 80309 USA. Univ Wales Coll Cardiff, Cardiff CF1 3NS, S Glam, Wales. RP Nguyen, H (reprint author), Jet Propuls Lab, Oak Grove Dr,MS169-506, Pasadena, CA 91109 USA. EM Hien.T.Nguyen@jpl.nasa.gov NR 4 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 626 EP 628 DI 10.1016/j.nima.2005.12.123 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700095 ER PT J AU Silverberg, RF Benford, DJ Chen, TC Chervenak, J Finkbeiner, F Moseley, SH Duncan, WD Miller, NA Schmidt, DR Ullom, JN AF Silverberg, RF Benford, DJ Chen, TC Chervenak, J Finkbeiner, F Moseley, SH Duncan, WD Miller, NA Schmidt, DR Ullom, JN TI Integrated NIS electron-tunnelling refrigerator/superconducting bolometer SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE TES bolometer; NIS refrigerator; transition-edge sensor; TES bolometer array AB We describe progress in the development of a close-packed array of bolometers designed for use in photometric applications at millimeter wavelengths from ground-based telescopes. Each bolometer in the array will use a proximity-effect Transition Edge Sensor (TES) sensing element and each will have integrated Normal-Insulator-Superconductor (NIS) refrigerators to cool the bolometer below the thermal reservoir temperature. The NIS refrigerators and acoustic-phonon-mode-isolated bolometers are fabricated on silicon. The radiation absorbing element is mechanically suspended by four legs, whose dimensions are used to control and optimize the thermal conductance of the bolometer. Using the technology developed at NIST, we fabricate NIS refrigerators at the base of each of the suspension legs. The NIS refrigerators remove hot electrons by quantum-mechanical tunneling and are expected to cool the biased (10 pW) bolometers to < 170 mK while the bolometers are inside a pumped 3 He-cooled cryostat operating at similar to 280 mK. This significantly lower temperature at the bolometer allows the detectors to approach background-limited performance despite the simple cryogenic system. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Lab Expt Cosmol, Greenbelt, MD 20771 USA. Global Sci & Technol, Greenbelt, MD 20771 USA. SSAI, Greenbelt, MD 20771 USA. Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Silverberg, RF (reprint author), NASA, Goddard Space Flight Ctr, Lab Expt Cosmol, Code 661, Greenbelt, MD 20771 USA. EM robert.silverberg@nasa.gov RI Tomlin, Nathan/A-4927-2009; Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012 OI Tomlin, Nathan/0000-0002-8313-9045; Benford, Dominic/0000-0002-9884-4206; NR 5 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 630 EP 632 DI 10.1016/j.nima.2005.12.205 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700096 ER PT J AU Fujimoto, R Mitsuda, K Hirabayashi, M Narasaki, K Breon, S Boyle, R DiPirro, M Volz, SM Kelley, RL AF Fujimoto, R Mitsuda, K Hirabayashi, M Narasaki, K Breon, S Boyle, R DiPirro, M Volz, SM Kelley, RL TI Neon dewar for the X-ray spectrometer onboard Suzaku SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE refrigerator; dewar; Astro-E2; XRS; X-ray microcalorimeter AB The X-ray spectrometer (XRS) onboard Suzaku is the first X-ray microcalorimeter array in orbit. The sensor array is operated at 60mK, which is attained by an adiabatic demagnetization refrigerator and superfluid liquid helium. The neon dewar is a vacuum-insulated container for the XRS. The requirements for the XRS dewar are to maintain the detector and the cryogenic system under the mechanical environment at launch (similar to 15 G), and to attain a lifetime of 3 years in a near-earth orbit. It is characterized with adoptions of solid neon as the second cryogen and a mechanical cooler, design optimization of the support straps for the neon tank to reduce the heat load as much as possible, and shock absorbers to mitigate the mechanical environment at launch. Microphonics from the mechanical cooler was one of the concerns for the detector performance, but the ground test results proved that they do not interfere with the detector. After about 1 month in orbit, its thermal performance showed that the dewar potentially achieves its design goals. (c) 2006 Elsevier B.V. All rights reserved. C1 Inst Space & Astronaut Sci, JAXA, Sagamihara, Kanagawa 2298510, Japan. Sumitomo Heavy Ind Ltd, Niihama 7928588, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA Headquarters, Washington, DC 20546 USA. RP Fujimoto, R (reprint author), Inst Space & Astronaut Sci, JAXA, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 2298510, Japan. EM fujimoto@isas.jaxa.jp RI Mitsuda, Kazuhisa/C-2649-2008; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 NR 0 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 648 EP 650 DI 10.1016/j.nima.2005.12.093 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700101 ER PT J AU Shirron, P Wegel, D DiPirro, M Sheldon, S AF Shirron, P Wegel, D DiPirro, M Sheldon, S TI An adiabatic demagnetization refrigerator capable of continuous cooling at 10mK and below SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE adiabatic demagnetization refrigerator; magnetic refrigeration; low temperature; space astronomy AB Upcoming far-IR space missions are faced with a very challenging requirement: to make detectors with sufficient sensitivity to be limited by the photon noise present in the darkness of space. At long wavelengths (> 100 mu m), where the Zodiacal light is insignificant and the sky brightness corresponds to only similar to 100aW, detectors must have noise equivalent powers of < 10(-19)W/root Hz. For fundamental reasons, this can only be achieved with detectors operating at similar to 20mK, giving rise to the need for coolers operating as low as 10mK. Only adiabatic demagnetization refrigerators (ADR) have demonstrated both zero-g operation and the capacity for cooling into this regime. We have recently developed a multi-stage ADR that can produce continuous cooling at temperatures of 35 mK or lower, and have begun developing additional stages that will enable 10mK operation. We describe the design and development program for this ADR. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Shirron, P (reprint author), NASA, Goddard Space Flight Ctr, Code 552, Greenbelt, MD 20771 USA. EM Peter.Shirron@nasa.gov NR 3 TC 2 Z9 2 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 651 EP 653 DI 10.1016/j.nima.2005.12.094 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700102 ER PT J AU Benford, DJ Dipirro, MJ Forgione, JB Jackson, ML Moseley, SH Panek, J Shirron, PJ Staguhn, JG AF Benford, DJ Dipirro, MJ Forgione, JB Jackson, ML Moseley, SH Panek, J Shirron, PJ Staguhn, JG TI Design and performance of a 50 mK rapid turnaround detector characterization system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE cryostal; adiabatic demagnetization refrigerator; bolometer superconductor; transition edge sensor ID ARRAYS AB Upcoming major NASA missions such as the Einstein Inflation Probe and the Single Aperture Far-Infrared Observatory will require arrays of detectors with thousands of background-limited elements sensitive to wavelengths from similar to 50 mu m to similar to 3 mm. Because of the low power levels present in space with cryogenic telescopes, these detectors will likely operate at temperatures below 100mK. In order to make rapid progress on detector development, the cryogenic testing cycle must be made convenient and quick. We have developed a cryogenic detector characterization system capable of testing superconducting detector arrays in formats up to 8 x 32, read out by SQUID multiplexers. The system relies on the cooling of a two-stage adiabatic demagnetization refrigerator immersed ill a liquid helium bath. This approach permits a detector to be cooled from 300 K to 50 mK in under 6 h, so that a test cycle begun in the morning will be over by the end of the day. The system is modular, with two identical immersible units, so that while one unit is cooling, the second call be reconfigured for the next battery of tests. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SSAI, Lanham, MD 20706 USA. RP Benford, DJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM Dominic.Benford@nasa.gov RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 5 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 660 EP 662 DI 10.1016/j.nima.2005.12.177 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700105 ER PT J AU Shirron, PJ DiPirro, MJ Panek, J Kelley, R Mitsuda, K Fujimoto, R Hirabayashi, M McCammon, D AF Shirron, PJ DiPirro, MJ Panek, J Kelley, R Mitsuda, K Fujimoto, R Hirabayashi, M McCammon, D TI The Astro-E2/XRS-2 helium insert system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE space cryogenics; space atronomy; superfluid helium; magnetic refrigeration AB The X-ray Spectrometer (XRS-2) instrument on the Japanese Space Agency (JAXA) Astro-E2 spacecraft will measure faint X-ray emissions in the energy range of 0.2-10 keV. A square array of 32 X-ray microcalorimeters used will be able to distinguish individual photons to better than 10 eV at 6 keV, with a quantum efficiency near 100%. The detectors are cooled to 60 mK by means of an adiabatic demagnetization refrigerator (ADR). The ADR rejects heat to a 1.3 K superfluid helium tank, which is surrounded by a 17 K solid neon tank. A Stirling cycle cryocooler precools an outer shield around the neon tank. This system will provide an estimated 3 years of on-orbit lifetime. This paper describes the helium insert, the ADR, the high temperature superconducting leads, and early on-orbit performance. Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. ISAS, JAXA, Sagamihara, Kanagawa 2298510, Japan. Sumitomo Heavy Ind, Niihama, Ehime 7928588, Japan. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Shirron, PJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM Peter.Shirron@nasa.gov RI Mitsuda, Kazuhisa/C-2649-2008; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 NR 5 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 666 EP 668 DI 10.1016/j.nima.2005.12.098 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700107 ER PT J AU Saab, T Bandler, SR Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, RL Kilbourne, CA Lindeman, MA Porter, FS Sadleir, J AF Saab, T Bandler, SR Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, RL Kilbourne, CA Lindeman, MA Porter, FS Sadleir, J TI Determination of complex microcalorimeter parameters with impedance measurements SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE X-ray spectrometer; microcalorimeter; impedance measurements AB The proper understanding and modeling of a microcalorimeter's response requires accurate knowledge of a handful of parameters, such as C, G, alpha. While a few of these parameters are directly determined from the TV characteristics, some others, notoriously the heat capacity (C) and alpha, appear in degenerate combinations in most measurable quantities. The consideration of a complex microcalorimeter leads to an added ambiguity in the determination of the parameters. In general, the dependence of the microcalorimeter's complex impedance on these various parameters varies with frequency. This dependence allows us to determine individual parameters by fitting the prediction of the microcalorimeter model to impedance data. In this paper we describe efforts at characterizing the Goddard X-ray microcalorimeters. With the parameters determined by this method, we compare the pulse shape and noise spectra predictions to data taken with the same devices. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Saab, T (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM tsaab@phys.ufl.edu RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 3 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 712 EP 714 DI 10.1016/j.nima.2005.12.112 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700121 ER PT J AU Lindeman, MA Anderson, MB Bandler, SR Bilgri, N Chervenak, J Crowder, SG Fallows, S Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, R Kilbourne, CA Lai, T Man, J McCammon, D Nelms, KL Porter, FS Rocks, LE Saab, T Sadleir, J Vidugiris, G AF Lindeman, MA Anderson, MB Bandler, SR Bilgri, N Chervenak, J Crowder, SG Fallows, S Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, R Kilbourne, CA Lai, T Man, J McCammon, D Nelms, KL Porter, FS Rocks, LE Saab, T Sadleir, J Vidugiris, G TI Percolation model of excess electrical noise in transition-edge sensors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE percolation; superconductor; resistor network; transition edge sensor; reduced excess noise; calorimeter; beta; non-ohmic resistor AB We present a geometrical model to describe excess electrical noise in transition-edge sensors (TESs). In this model, a network of fluctuating resistors represents the complex dynamics inside a TES. The fluctuations can cause several resistors in series to become superconducting. Such events short out part of the TES and generate noise because much of the current percolates through low resistance paths. The model predicts that excess white noise increases with decreasing TES bias resistance (R/R-N) and that perpendicular zebra stripes reduce noise and alpha of the TES by reducing percolation. (c) 2006 Elsevier B.V. All rights reserved. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lindeman, MA (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. EM lindeman@wisp.physics.wisc.edu RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 4 TC 11 Z9 11 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 715 EP 717 DI 10.1016/j.nima.2005.12.114 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700122 ER PT J AU Crowder, SG Lindeman, MA Anderson, MB Bandler, SR Bilgri, N Bruijn, MP Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Germeau, A Hoevers, HFC Iyomoto, N Kelly, R Kilbourne, CA Lai, T Man, J McCammon, D Nelms, KL Porter, FS Rocks, L Saab, T Sadleir, J Vidugiris, G AF Crowder, SG Lindeman, MA Anderson, MB Bandler, SR Bilgri, N Bruijn, MP Chervenak, J Figueroa-Feliciano, E Finkbeiner, F Germeau, A Hoevers, HFC Iyomoto, N Kelly, R Kilbourne, CA Lai, T Man, J McCammon, D Nelms, KL Porter, FS Rocks, L Saab, T Sadleir, J Vidugiris, G TI An investigation of excess noise in transition-edge sensors on a solid silicon substrate SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE transition edge sensor; unsuspended device; excess noise; calorimeter AB Transition-edge sensors (TESs) exhibit two major types of excess noise above the expected and unavoidable thermodynamic fluctuation noise (TFN) to the heat sink and Johnson noise. High-resistance TESs Such as those made by the Netherlands Institute for Space Research (SRON) show excess noise consistent with internal TFN (ITFN) caused by random energy transport within the TES itself while low resistance TESs show an excess voltage noise of unknown origin seemingly unrelated to temperature fluctuations. Running a high-resistance TES on a high thermal conductivity substrate should suppress ITFN and allow detection of any excess voltage noise. We tested two TESs oil a solid silicon substrate fabricated by SRON of a relatively high normal state resistance of similar to 200 m Omega. After determining a linear model of the TES response to noise for the devices, we found little excess TFN and little excess voltage noise for bias currents of up to similar to 20 mu A. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SRON, Netherlands Inst Space Res, NL-3584 CA Utrecht, Netherlands. RP Crowder, SG (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. EM sgcrowder@wisc.edu RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 2 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 721 EP 723 DI 10.1016/j.nima.2005.12.117 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700124 ER PT J AU Mazin, BA Day, PK Irwin, KD Reintsema, CD Zmuidzinas, J AF Mazin, BA Day, PK Irwin, KD Reintsema, CD Zmuidzinas, J TI Digital readouts for large microwave low-temperature detector arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE software radio; MKID; kinetic inductance; detector readout AB Over the last several years many different types of low-temperature detectors (LTDs) have been developed that use a microwave resonant circuit as part of their readout. These devices include microwave kinetic inductance detectors (MKID), microwave SQUID readouts for transition edge sensors (TES), and NIS bolometers. Current readout techniques for these devices use analog frequency synthesizers and IQ mixers. While these components are available as microwave integrated circuits, one set is required for each resonator. We are exploring a new readout technique for this class of detectors based on a commercial-off-the-shelf technology called software defined radio (SDR). In this method a fast digital to analog (D/A) converter creates as many tones as desired in the available bandwidth. Our prototype system employs a 100MS/s 16-bit D/A to generate an arbitrary number of tones in 50 MHz of bandwidth. This signal is then mixed up to the desired detector resonant frequency (similar to 10GHz), sent through the detector, then mixed back down to baseband. The baseband signal is then digitized with a series of fast analog to digital converters (80 MS/s, 14-bit). Next, a numerical mixer in a dedicated integrated circuit or FPGA mixes the resonant frequency of a specified detector to 0 Hz, and sends the complex detector Output over a computer bus for processing and storage. In this paper we will report on Our results in using a prototype system to readout a MKID array, including system noise performance, X-ray pulse response, and cross-talk measurements. We will also discuss how this technique can be scaled to read out many thousands of detectors. (c) 2006 Published by Elsevier B.V. C1 NASA, Jet Prop Lab, Pasadena, CA 91109 USA. NIST, Boulder, CO 80305 USA. CALTECH, Pasadena, CA 91125 USA. RP Mazin, BA (reprint author), NASA, Jet Prop Lab, 4800 Oak Grove Dr,M-S 169-506, Pasadena, CA 91109 USA. EM bam@astro.caltech.edu RI Mazin, Ben/B-8704-2011 OI Mazin, Ben/0000-0003-0526-1114 NR 4 TC 28 Z9 28 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 799 EP 801 DI 10.1016/j.nima.2005.12.208 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700148 ER PT J AU Bandler, SR Figueroa-Feliciano, E Iyomoto, N Kelley, RL Kilbourne, CA Murphy, KD Porter, FS Saab, T Sadleir, J AF Bandler, SR Figueroa-Feliciano, E Iyomoto, N Kelley, RL Kilbourne, CA Murphy, KD Porter, FS Saab, T Sadleir, J TI Non-linear effects in transition edge sensors for X-ray detection SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Low-Temperature Detectors CY JUL 31-AUG 05, 2005 CL Univ Tokyo, Tokyo, JAPAN HO Univ Tokyo DE microcalorimeter; non-linear; transition-edge sensor AB In a microcalorimeter that uses a transition-edge sensor to detect energy depositions, the small signal energy resolution improves with decreasing heat capacity. This improvement remains true up to the point where non-linear and saturation effects become significant. This happens when the energy deposition causes a significant change in the sensor resistance. Not only does the signal size become a nonlinear function of the energy deposited, but also the noise becomes non-stationary over the duration of the pulse. Algorithms have been developed that can calculate the optimal performance given this non-linear behavior that typically requires significant processing and calibration work-both of which are impractical for space missions. We have investigated the relative importance of the various nonlinear effects, with the hope that a computationally simple transformation can overcome the largest of the non-linear and non-stationary effects, producing a highly linear "gain" for pulse-height versus energy, and close to the best energy resolution at all energies when using a Wiener filter. (c) 2006 Published by Elsevier B.V. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Bandler, SR (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM sbandler@milkyway.gsfc.nasa.gov RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 3 TC 10 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 15 PY 2006 VL 559 IS 2 BP 817 EP 819 DI 10.1016/j.nima.2005.12.149 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 035BL UT WOS:000236974700154 ER PT J AU Matsko, AB Savchenkov, AA Maleki, L AF Matsko, AB Savchenkov, AA Maleki, L TI Ring-down spectroscopy for studying properties of CW Raman lasers SO OPTICS COMMUNICATIONS LA English DT Article ID SCATTERING AB We describe theoretically a simple technique for analyzing the conversion efficiency and the oscillation threshold of all-resonant intracavity Raman lasers. The method is based on a dependence of the ring-down time of the pump cavity mode oil the energy accumulated ill the cavity. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Matsko, AB (reprint author), CALTECH, Jet Propuls Lab, MS 298-100,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Andrey.Matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 14 TC 10 Z9 10 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD APR 15 PY 2006 VL 260 IS 2 BP 662 EP 665 DI 10.1016/j.optcom.2005.11.005 PG 4 WC Optics SC Optics GA 029WJ UT WOS:000236594800047 ER PT J AU Kaufman, YJ Gobbi, GP Koren, I AF Kaufman, YJ Gobbi, GP Koren, I TI Aerosol climatology using a tunable spectral variability cloud screening of AERONET data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OPTICAL DEPTH; SATELLITE; OCEAN AB Aerosols, humidity and clouds are often correlated. Therefore, rigorous cloud screening can systematically bias toward less cloudy and drier conditions, underestimating the average aerosol optical thickness (AOT). Here, using AERONET data we show that systematic rejection of variable atmospheric optical conditions can generate such bias in the average AOT. Therefore we recommend two approaches to deal with cloud contamination: (1) to introduce more powerful spectral variability cloud screening and (2) to retain most of the data despite cloud contamination, estimate average cloud contamination and to correct for it. Both methods are applied to aerosol with Angstrom exponent >0.3 and compared with the AERONET cloud screened level 1.5 data. The new methods do not apply for pure dust. Analysis for 10 AERONET stations with similar to 4 years of data, shows almost no change for Rome (Italy), but up to a change in AOT of 0.12 or +30% in Beijing (PRC). C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CNR, Ist Sci Atmosfera & Clima, I-00133 Rome, Italy. Weizmann Inst Sci, Dept Environm Sci, IL-76100 Rehovot, Israel. RP Kaufman, YJ (reprint author), NASA, Goddard Space Flight Ctr, Code 613-2, Greenbelt, MD 20771 USA. EM kaufman@climate.gsfc.nasa.gov RI Koren, Ilan/K-1417-2012 OI Koren, Ilan/0000-0001-6759-6265 NR 13 TC 22 Z9 22 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 14 PY 2006 VL 33 IS 7 AR L07817 DI 10.1029/2005GL025478 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039DK UT WOS:000237281100002 ER PT J AU Schuster, GL Dubovik, O Holben, BN AF Schuster, GL Dubovik, O Holben, BN TI Angstrom exponent and bimodal aerosol size distributions SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SINGLE-SCATTERING ALBEDO; SKY RADIANCE MEASUREMENTS; OPTICAL-PROPERTIES; ATMOSPHERIC AEROSOL; WAVELENGTH DEPENDENCE; RETRIEVAL ALGORITHM; DEPTH; VARIABILITY; PARTICLES; TURBIDITY AB Power laws have long been used to describe the spectral dependence of aerosol extinction, and the wavelength exponent of the aerosol extinction law is commonly referred to as the Angstrom exponent. The Angstrom exponent is often used as a qualitative indicator of aerosol particle size, with values greater than 2 indicating small particles associated with combustion byproducts, and values less than 1 indicating large particles like sea salt and dust. In this study, we investigate the relationship between the Angstrom exponent and the mode parameters of bimodal aerosol size distributions using Mie theory calculations and Aerosol Robotic Network (AERONET) retrievals. We find that Angstrom exponents based upon seven wavelengths (0.34, 0.38, 0.44, 0.5, 0.67, 0.87, and 1.02 mu m) are sensitive to the volume fraction of aerosols with radii less then 0.6 mu m but not to the fine mode effective radius. The Angstrom exponent is also known to vary with wavelength, which is commonly referred to as curvature; we show how the spectral curvature can provide additional information about aerosol size distributions for intermediate values of the Angstrom exponent. Curvature also has a significant effect on the conclusions that can be drawn about two-wavelength Angstrom exponents; long wavelengths (0.67, 0.87 mu m) are sensitive to fine mode volume fraction of aerosols but not fine mode effective radius, while short wavelengths (0.38, 0.44 mu m) are sensitive to the fine mode effective radius but not the fine mode volume fraction. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP NASA, Langley Res Ctr, Hampton, VA 23681 USA. EM gregory.l.schuster@nasa.gov RI Dubovik, Oleg/A-8235-2009 OI Dubovik, Oleg/0000-0003-3482-6460 NR 55 TC 269 Z9 277 U1 7 U2 52 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 14 PY 2006 VL 111 IS D7 AR D07207 DI 10.1029/2005JD006328 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 039DP UT WOS:000237281700003 ER PT J AU Li, LM Ingersoll, AP Vasavada, AR Simon-Miller, AA Del Genio, AD Ewald, SP Porco, CC West, RA AF Li, LM Ingersoll, AP Vasavada, AR Simon-Miller, AA Del Genio, AD Ewald, SP Porco, CC West, RA TI Vertical wind shear on Jupiter from Cassini images SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MEAN ZONAL FLOW; MOIST CONVECTION; JOVIAN ATMOSPHERE; CLOUD STRUCTURE; VOYAGER IMAGES; GALILEO PROBE; GIANT PLANETS; MODEL; STABILITY; MOTIONS AB Multifilter images of Jupiter acquired by the Cassini Imaging Science Subsystem (ISS) are used to derive zonal winds at altitudes above and below the visible cloud deck. Small features unique to the ultraviolet images of ISS are tracked to get the systematic high-altitude zonal winds. Comparison between the zonal winds from ultraviolet images and the vertical profile of zonal winds from the Cassini Composite Infrared Spectrometer (CIRS) shows that the zonal winds from the ultraviolet images are from a pressure level that is similar to 0.2 scale heights higher than the pressure level of the zonal winds from continuum-band images. Deeper zonal winds at different latitudes of the equatorial region are measured by tracking cloud features observed within hot spots on continuum-band images. The deeper zonal winds in this study extend the measurement of the Galileo probe to different latitudes of the equatorial region. Comparison between the Galileo probe and this study suggests that these fast-moving clouds within hot spots are deeper than 3 bars and are therefore probably water clouds. C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. CICLOPS Space Sci Inst, Boulder, CO USA. RP Li, LM (reprint author), CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. EM liming@gps.caltech.edu; api@gps.caltech.edu; ashwin.r.vasavada@jpl.nasa.gov; simon@lepasm.gsfc.nasa.gov; delgenio@giss.nasa.gov; spe@gps.caltech.edu; carolyn@ciclops.org; robert.a.west@jpl.nasa.gov RI Del Genio, Anthony/D-4663-2012; Simon, Amy/C-8020-2012 OI Del Genio, Anthony/0000-0001-7450-1359; Simon, Amy/0000-0003-4641-6186 NR 39 TC 12 Z9 12 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 14 PY 2006 VL 111 IS E4 AR E04004 DI 10.1029/2005JE002556 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 039EA UT WOS:000237283200001 ER PT J AU Holmes, TRH de Rosnay, P de Jeu, R Wigneron, RJP Kerr, Y Calvet, JC Escorihuela, MJ Saleh, K Lemaitre, F AF Holmes, TRH de Rosnay, P de Jeu, R Wigneron, RJP Kerr, Y Calvet, JC Escorihuela, MJ Saleh, K Lemaitre, F TI A new parameterization of the effective temperature for L band radiometry SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MICROWAVE EMISSION; SOIL-MOISTURE AB An accurate value of the effective temperature is critical for soil emissivity retrieval, and hence soil moisture content retrieval, from passive microwave observations. Computation of the effective temperature needs fine profile measurements of soil temperature and soil moisture. The availability of a two year long data set of these surface variables from SMOSREX ( Surface Monitoring Of the Soil Reservoir EXperiment) makes it possible to study the effective temperature at the seasonal to interannual scale. This study shows that present parameterizations do not adequately describe the seasonal variations in sensing depth. Therefore, a new parameterization is proposed that is stable at the seasonal to interannual scales while retaining simplicity. C1 Ctr Etud Spatiales Biosphere, UMR 5126, UPS, CNRS,CNES,IRD, F-31401 Toulouse, France. Meteo France, CNRM, GAME, URA 1357,CNRS, F-31057 Toulouse 1, France. Vrije Univ Amsterdam, Dept Hydrol & Geoenvironm Sci, Fac Earth & Life Sci, NL-1081 HV Amsterdam, Netherlands. Off Natl Etud & Rech Aerosp, F-31055 Toulouse 4, France. Inst Natl Rech Agron, Bordeaux, France. RP Holmes, TRH (reprint author), NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. EM patricia.derosnay@cesbio.cnes.fr RI Calvet, Jean-Christophe/A-8762-2012; de Rosnay, Patricia/M-8203-2013; Holmes, Thomas/F-4512-2010 OI Calvet, Jean-Christophe/0000-0001-6425-6492; de Rosnay, Patricia/0000-0002-7374-3820; Holmes, Thomas/0000-0002-4651-0079 NR 10 TC 26 Z9 27 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 13 PY 2006 VL 33 IS 7 AR L07405 DI 10.1029/2006GL025724 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039DJ UT WOS:000237281000005 ER PT J AU Tang, X Chen, BD AF Tang, X Chen, BD TI Cloud types associated with the Asian summer monsoons as determined from MODIS/TERRA measurements and a comparison with surface observations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID REGION; MODIS; WATER; TOP AB Using a 6-year June-July-August MODIS/Terra-measured cloud properties data set, the characteristics of clouds associated with the Asian summer monsoons are examined. The results indicate that a large amount of high clouds exists in the Indian monsoon region and account for approximately 65% of all cloud grids. Moreover, the interannual variation of high clouds is not apparent. In the East Asian monsoon region, high clouds show a relatively strong interannual variation and account for roughly 38.5% of all cloud grids. The overall percentages of middle and low clouds are comparable to each other within the East Asian monsoon region. Moreover three high cloud types have been identified to coexist in the Indian monsoon regions, i.e., cirrus, cirrostratus and deep convective clouds. Among them, cirrostratus has the largest percentage. In the East Asian monsoon region, the most frequently occurring cloud type is stratocumulus. However, compared with cloud climatology of surface observations, middle and low clouds are severely underestimated in the Asian monsoon regions by the MODIS/ Terra measurements; in particular, the underestimation for low clouds is up to 80% in the Indian monsoon region. Therefore, great caution is needed when using the MODIS data to analyze middle and low clouds, especially when high and thick clouds exist. C1 Shanghai Meteorol Bur, Shanghai 200030, Peoples R China. NASA, Goddard Space Flight Ctr, SAIC, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. Peking Univ, Dept Atmospher Sci, Sch Phys, Beijing 100871, Peoples R China. Sci Applicat Int Corp, San Diego, CA 92121 USA. RP Tang, X (reprint author), Shanghai Meteorol Bur, 166 Puxi Rd, Shanghai 200030, Peoples R China. EM tangxu570512@vip.sina.com NR 12 TC 7 Z9 8 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 13 PY 2006 VL 33 IS 7 AR L07814 DI 10.1029/2006GL026004 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039DJ UT WOS:000237281000009 ER PT J AU Teague, WJ Jarosz, E Keen, TR Wang, DW Hulbert, MS AF Teague, WJ Jarosz, E Keen, TR Wang, DW Hulbert, MS TI Bottom scour observed under Hurricane Ivan SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CONTINENTAL-SHELF; WAVES; BED AB Observations that extensive bottom scour along the outer continental shelf under Hurricane Ivan resulted in the displacement of more than 100 million cubic meters of sediment from a 35 x 15 km region directly under the storm's path are presented. Sediment resuspension was accomplished by the extreme waves generated by Ivan and transported by strong near-bottom wind-driven currents. The sediment transport was primarily westward along the shelf, but also contained a significant offshore component, suggesting sediment was transported toward the Mississippi Delta and that it may have accumulated near the shelf break and on the upper continental slope. The maximum observed scour of about 32 and 36 cm took place at two locations approximately 17 km apart along the 60 m isobath over which the maximum wind stress occurred. C1 USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. RP Teague, WJ (reprint author), USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. EM teague@nrlssc.navy.mil NR 14 TC 12 Z9 13 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 13 PY 2006 VL 33 IS 7 AR L07607 DI 10.1029/2005GL025281 PG 3 WC Geosciences, Multidisciplinary SC Geology GA 039DJ UT WOS:000237281000003 ER PT J AU Pierre, MC Genc, KO Litow, M Humphreys, B Rice, AJ Maender, CC Cavanagh, PR AF Pierre, Mark C. Genc, Kerim O. Litow, Micah Humphreys, Brad Rice, Andrea J. Maender, Christian C. Cavanagh, Peter R. TI Comparison of knee motion on Earth and in space: an observational study SO JOURNAL OF NEUROENGINEERING AND REHABILITATION LA English DT Article ID SKELETAL-MUSCLE; MICROGRAVITY; SPACEFLIGHT; MODELS; JOINT; ADAPTATIONS; ISOFORMS; ATROPHY AB Background: Spaceflight has been shown to cause atrophy, reduced functional capacity, and increased fatigue in lower-limb skeletal muscles. The mechanisms of these losses are not fully understood but are thought to result, in part, from alteration in muscle usage. Methods: Knee-joint angles and lower-extremity muscle activity were measured continually, via elecrogoniometry and surface electromyography respectively, from two subjects during entire working days of activity on Earth and onboard the International Space Station (ISS). Results: On Earth the distribution of angular positions of the knee was typically bimodal, with peaks of > 75 degrees of flexion and in almost full extension (< 15 degrees of flexion). However, on the ISS, a single peak in the mid-range of the available range of motion was seen. The knee joint was also moved through fewer excursions and the excursions were smaller in amplitude, resulting in a reduced span of angles traversed. The velocities of the excursions in space were lower than those used on Earth. Conclusion: These results demonstrate that, in space, overall knee-joint motion is reduced, and there is a transformation in the type of muscle action compared to that seen on Earth, with more isometric action at the expense of concentric and particularly eccentric action. C1 Cleveland Clin, Lemer Res Inst, Dept Biomed Engn, Cleveland, OH 44106 USA. Cleveland Clin, Ctr Space Med, Cleveland, OH 44106 USA. Cleveland Clin, Dept Orthopaed Surg, Cleveland, OH 44106 USA. Cleveland Clin, Orthopaed Res Ctr, Cleveland, OH 44106 USA. Case Western Reserve Univ, Cleveland, OH 44106 USA. Zin Technol Inc, Brookpark, OH USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Cavanagh, PR (reprint author), Cleveland Clin, Lemer Res Inst, Dept Biomed Engn, Cleveland, OH 44106 USA. EM pierrem@ccf.org; genck@ccf.org; mxl87@case.edu; brad.humphreys@zin-tech.com; ricea1@ccf.org; christian.c.maender@nasa.gov; cavanap@ccf.org NR 25 TC 3 Z9 5 U1 1 U2 3 PU BIOMED CENTRAL LTD PI LONDON PA MIDDLESEX HOUSE, 34-42 CLEVELAND ST, LONDON W1T 4LB, ENGLAND SN 1743-0003 J9 J NEUROENG REHABIL JI J. NeuroEng. Rehabil. PD APR 13 PY 2006 VL 3 AR 8 DI 10.1186/1743-0003-3-8 PG 8 WC Engineering, Biomedical; Neurosciences; Rehabilitation SC Engineering; Neurosciences & Neurology; Rehabilitation GA 235FM UT WOS:000251218900001 PM 16613607 ER PT J AU Whiteman, DN Russo, F Demoz, B Miloshevich, LM Veselovskii, I Hannon, S Wang, Z Vomel, H Schmidlin, F Lesht, B Moore, PJ Beebe, AS Gambacorta, A Barnet, C AF Whiteman, DN Russo, F Demoz, B Miloshevich, LM Veselovskii, I Hannon, S Wang, Z Vomel, H Schmidlin, F Lesht, B Moore, PJ Beebe, AS Gambacorta, A Barnet, C TI Analysis of Raman lidar and radiosonde measurements from the AWEX-G field campaign and its relation to Aqua validation SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WATER-VAPOR MEASUREMENTS; MICROWAVE RADIOMETER; TEMPERATURE; RETRIEVALS; HYGROMETER; PROFILES; HUMIDITY; PROJECT; LINE AB [1] Early work within the Aqua validation activity revealed there to be large differences in water vapor measurement accuracy among the various technologies in use for providing validation data. The validation measurements were made at globally distributed sites making it difficult to isolate the sources of the apparent measurement differences among the various sensors, which included both Raman lidar and radiosonde. Because of this, the AIRS Water Vapor Experiment - Ground (AWEX-G) was held in October-November 2003 with the goal of bringing validation technologies to a common site for intercomparison and resolving the measurement discrepancies. Using the University of Colorado Cryogenic Frostpoint Hygrometer (CFH) as the water vapor reference, the AWEX-G field campaign permitted correction techniques to be validated for Raman lidar, Vaisala RS80-H and RS90/92 that significantly improve the absolute accuracy of water vapor measurements from these systems particularly in the upper troposphere. Mean comparisons of radiosondes and lidar are performed demonstrating agreement between corrected sensors and the CFH to generally within 5% thereby providing data of sufficient accuracy for Aqua validation purposes. Examples of the use of the correction techniques in radiance and retrieval comparisons are provided and discussed. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. US DOE, Argonne Natl Lab, Chicago, IL USA. LJT & Associates, Wallops Isl, VA USA. SGT Inc, Greenbelt, MD USA. NOAA, Camp Springs, MD 20746 USA. RP Whiteman, DN (reprint author), NASA, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA. EM david.n.whiteman@nasa.gov RI Gambacorta, Antonia/E-7937-2011; Wang, Zhien/F-4857-2011; Barnet, Christopher/F-5573-2010; Demoz, Belay/N-4130-2014; OI Gambacorta, Antonia/0000-0002-2446-9132; Lesht, Barry/0000-0003-0801-4290 NR 21 TC 26 Z9 26 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 12 PY 2006 VL 111 IS D9 AR D09S09 DI 10.1029/2005JD006429 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 039DS UT WOS:000237282100001 ER PT J AU Cravens, TE Robertson, IP Waite, JH Yelle, RV Kasprzak, WT Keller, CN Ledvina, SA Niemann, HB Luhmann, JG McNutt, RL Ip, WH De La Haye, V Mueller-Wodarg, I Wahlund, JE Anicich, VG Vuitton, V AF Cravens, TE Robertson, IP Waite, JH Yelle, RV Kasprzak, WT Keller, CN Ledvina, SA Niemann, HB Luhmann, JG McNutt, RL Ip, WH De La Haye, V Mueller-Wodarg, I Wahlund, JE Anicich, VG Vuitton, V TI Composition of titan's ionosphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ION-MOLECULE; ATMOSPHERE; MODEL; CHEMISTRY; PLASMA AB We present Cassini Ion and Neutral Mass Spectrometer (INMS) measurements of ion densities on the nightside of Titan from April 16, 2005, and show that a substantial ionosphere exists on the nightside and that complex ion chemistry is operating there. The total ionospheric densities measured both by the INMS and the Cassini Radio and Plasma Wave (RPWS) experiments on Cassini suggest that precipitation from the magnetosphere into the atmosphere of electrons with energies ranging from 25 eV up to about 2 keV is taking place. The absence of ionospheric composition measurements has been a major obstacle to understanding the ionosphere. Seven "families'' of ion species, separated in mass-to-charge ratio by 12 Daltons (i.e., the mass of carbon), were observed and establish the importance of hydrocarbon and nitrile chains in the upper atmosphere. Several of the ion species measured by the INMS were predicted by models (e.g., HCNH+ and C2H5+). But the INMS also saw high densities at mass numbers not predicted by models, including mass 18, which we suggest will be ammonium ions (NH4+) produced by reaction of other ion species with neutral ammonia. C1 Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Natl Cent Univ, Inst Astron, Chungli 32054, Taiwan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Cornerstone Univ, Div Sci Math & Kinesiol, Grand Rapids, MI 49525 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ London Imperial Coll Sci Technol & Med, Space & Atmospher Phys Grp, London SW7 2BW, England. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Swedish Inst Space Phys, SE-75591 Uppsala, Sweden. Natl Cent Univ, Inst Space Sci, Chungli 32054, Taiwan. RP Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. EM cravens@ku.edu RI McNutt, Ralph/E-8006-2010; Mueller-Wodarg, Ingo/M-9945-2014; OI McNutt, Ralph/0000-0002-4722-9166; Mueller-Wodarg, Ingo/0000-0001-6308-7826; Ledvina, Stephen/0000-0002-2450-775X NR 26 TC 132 Z9 132 U1 0 U2 13 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 11 PY 2006 VL 33 IS 7 AR L07105 DI 10.1029/2005GL025575 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 039DH UT WOS:000237280700005 ER PT J AU Tournadre, J Chapron, B Reul, N Vandemark, DC AF Tournadre, J Chapron, B Reul, N Vandemark, DC TI A satellite altimeter model for ocean slick detection SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SURFACE; TOPEX; SCATTEROMETER; ECHO AB [1] About 5% of Ku-band altimeter ocean data are degraded by the occurrence of high radar return cross sections (sigma(0)), usually called sigma(0) blooms. During blooms, which occur during no or low wind conditions, the mean altimeter waveform can significantly depart from the expected shape. In about 60% of the cases the waveforms are distorted to such an extent that either the range tracker loses lock or the off-nadir angle estimate becomes unrealistic. The analysis of high data rate altimeter waveforms during bloom events reveals the presence of V-shaped patterns similar to the ones observed during rain events. These patterns trace small-scale (i.e., smaller than the altimeter footprint) changes in surface backscatter. Such variations of surface roughness are commonly observed in SAR images under low wind conditions. On the basis of the experience gained through the analysis of high-resolution altimeter waveforms in the presence of rain cell, a model is developed to analyze the altimeter response to phenomena whose length scale is smaller than the altimeter footprint. The model is applied to simple patterns ( linear slicks and circular patches) as well as to realistic surface sigma(0) estimated by SAR. It is also used to analyze bloom events in terms of surface slicks. The model results shows that the small-scale sigma(0) variations explain the behavior of altimeter waveforms in bloom events. The results also show that a good proportion of data during bloom events are still valid for estimating geophysical parameters as the Brown model remains valid. Use of high-resolution altimeter waveforms may also offer an interesting mean to study marine slick occurrence rates and type. C1 IFREMER, Oceanog Lab, F-29280 Plouzane, France. NASA, Goddard Space Flight Ctr, Wallops Isl, VA 23337 USA. RP Tournadre, J (reprint author), IFREMER, Oceanog Lab, Technopole Pointe Diable, F-29280 Plouzane, France. EM jean.tournadre@ifremer.fr RI reul, nicolas/C-4895-2009; Chapron, Bertrand/O-6527-2015; tournadre, jean/F-8402-2010 OI tournadre, jean/0000-0003-1159-4388 NR 15 TC 22 Z9 22 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD APR 11 PY 2006 VL 111 IS C4 AR C04004 DI 10.1029/2005JC003109 PG 13 WC Oceanography SC Oceanography GA 039DV UT WOS:000237282600001 ER PT J AU Audley, MD Nagase, F Mitsuda, K Angelini, L Kelley, RL AF Audley, MD Nagase, F Mitsuda, K Angelini, L Kelley, RL TI ASCA observations of OAO 1657-415 and its dust-scattered X-ray halo SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE dust, extinction; X-rays : binaries; X-rays : individual : OAO 1657-415; X-rays : ISM ID CENTAURUS X-3; VELA X-1; OAO 1657-415; GRAINS; EMISSION; DISTANCE; ECLIPSE; GINGA; PHASE AB We report on two ASCA observations of the high-mass X-ray binary pulsar OAO 1657-415. A short observation near mid-eclipse caught the source in a low-intensity state, with a weak continuum and iron emission dominated by the 6.4-keV fluorescent line. A later, longer observation found the source in a high-intensity state and covered the uneclipsed through mid-eclipse phases. In the high-intensity state, the non-eclipse spectrum has an absorbed continuum component due to scattering by material near the pulsar and 80 per cent of the fluorescent iron emission comes from less than 19 light-second away from the pulsar. We find a dust-scattered X-ray halo whose intensity decays through the eclipse. We use this halo to estimate the distance to the source as 7.1 +/- 1.3 kpc. C1 Royal Observ, UK Astron Technol Ctr, Edinburgh EH9 3HJ, Midlothian, Scotland. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Audley, MD (reprint author), Royal Observ, UK Astron Technol Ctr, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland. EM audley@mrao.cam.ac.uk RI Mitsuda, Kazuhisa/C-2649-2008; Kelley, Richard/K-4474-2012 NR 29 TC 19 Z9 19 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2006 VL 367 IS 3 BP 1147 EP 1154 DI 10.1111/j.1365-2966.2006.10003.x PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 027AQ UT WOS:000236385600026 ER PT J AU Cantrell, JH AF Cantrell, JH TI Quantitative assessment of fatigue damage accumulation in wavy slip metals from acoustic harmonic generation SO PHILOSOPHICAL MAGAZINE LA English DT Article ID DISLOCATION PLASTICITY; COPPER; BANDS; MICROSTRUCTURES; ORGANIZATION; BEHAVIOR; DIPOLES; STRAIN; MODEL AB A comprehensive, analytical treatment is presented of the microelastic-plastic nonlinearities resulting from the interaction of a stress perturbation with dislocation substructures and cracks that evolve during cyclic fatigue of wavy slip metals. The interaction is quantified by a material nonlinearity parameter beta extracted from acoustic harmonic generation measurements. The contribution to beta from the substructures is obtained from the Cantrell model. The contribution to beta from cracks is obtained by applying the Paris law to the Nazarov-Sutin crack nonlinearity equation. The nonlinearity parameter resulting from the two contributions is predicted to increase monotonically by hundreds of percent during fatigue from the virgin state to fracture. The increase in beta during the first 80-90% fatigue life is dominated by the evolution of dislocation substructures, while the last 10-20% is dominated by crack growth. Application of the model to aluminium alloy 2024-T4 in stress-controlled loading at 276MPa yields excellent agreement between theory and experiment. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Cantrell, JH (reprint author), NASA, Langley Res Ctr, Mail Stop 231, Hampton, VA 23681 USA. EM john.h.cantrell@nasa.gov NR 28 TC 52 Z9 52 U1 1 U2 7 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1478-6435 J9 PHILOS MAG JI Philos. Mag. PD APR 11 PY 2006 VL 86 IS 11 BP 1539 EP 1554 DI 10.1080/14786430500365358 PG 16 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 027BQ UT WOS:000236389100004 ER PT J AU Fu, R Hu, YL Wright, JS Jiang, JH Dickinson, RE Chen, MX Filipiak, M Read, WG Waters, JW Wu, DL AF Fu, R Hu, YL Wright, JS Jiang, JH Dickinson, RE Chen, MX Filipiak, M Read, WG Waters, JW Wu, DL TI Short circuit of water vapor and polluted air to the global stratosphere by convective transport over the Tibetan Plateau SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE climate; CO; stratosphere water vapor ID TROPICAL TROPOPAUSE; TAPE-RECORDER; MONSOON; CLOUDS; DEHYDRATION; TROPOSPHERE; PRODUCTS; MISSION; RADIUS; MODEL AB During boreal summer, much of the water vapor and CO entering the global tropical stratosphere is transported over the Asian monsoon/Tibetan Plateau (TP) region. Studies have suggested that most of this transport is carried out either by tropical convection over the South Asian monsoon region or by extratropical convection over southern China. By using measurements from the newly available National Aeronautics and Space Administration Aura Microwave Limb Sounder, along with observations from the Aqua and Tropical Rainfall-Measuring Mission satellites, we establish that the TP provides the main pathway for cross-tropopause transport in this region. Tropospheric moist convection driven by elevated surface heating over the TIP is deeper and detrains more water vapor, CO, and ice at the tropopause than over the monsoon area. Warmer tropopause temperatures and slower-failing, smaller cirrus cloud particles in less saturated ambient air at the tropopause also allow more water vapor to travel into the lower stratosphere over the TP, effectively short-circuiting the slower ascent of water vapor across the cold tropical tropopause over the monsoon area. Air that is high in water vapor and CO over the Asian monsoon/TP region enters the lower stratosphere primarily over the TP, and it is then transported toward the Asian monsoon area and disperses into the large-scale upward motion of the global stratospheric circulation. Thus, hydration of the global stratosphere could be especially sensitive to changes of convection over the TP. C1 Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Sch Geosci, Inst Atmospher & Environm Sci, Edinburgh EH9 3JN, Midlothian, Scotland. RP Fu, R (reprint author), Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. EM fu@eas.gatech.edu RI Fu, Rong/B-4922-2011; Wu, Dong/D-5375-2012; OI Wright, Jonathon/0000-0001-6551-7017 NR 45 TC 132 Z9 156 U1 5 U2 30 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD APR 11 PY 2006 VL 103 IS 15 BP 5664 EP 5669 DI 10.1073/pnas.0601584103 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 034AK UT WOS:000236896200008 PM 16585523 ER PT J AU Titarchuk, L Chardonnet, P AF Titarchuk, L Chardonnet, P TI The observed galactic annihilation line: Possible signature of accreting small-mass black holes in the galactic center SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; Galaxy : center; radiation mechanisms : nonthermal ID X-RAY SOURCES; SUPERNOVA EJECTA FRAGMENTS; SAGITTARIUS-A-ASTERISK; CENTER REGION; INTERSTELLAR-MEDIUM; GAMMA-RAYS; IRON LINE; EMISSION; RADIATION; GALAXY AB Various balloon and satellite observatories have revealed what appears to be an extended source of 0.511 MeV annihilation radiation with a flux of similar to 10(-3) photons cm(-2) s(-1) centered on the Galactic center. Positrons from radioactive products of stellar explosions can account for a significant fraction of the emission. We discuss an additional source for this emission: namely, e(+)e(-) pairs produced when X-rays generated from the similar to 2.6 x 10(6) M-circle dot Galactic center black hole interact with similar to 10 MeV temperature blackbody emission from 10(17) g black holes within 10(14)-10(15) cm of the center. The number of such small-mass black holes (SMMBHs) can account for the production of the 10(42) e(+) s(-1) that produces the observed annihilation in the inner Galaxy when transport effects are taken into account. We consider the possibility for confirming the presence of these SMMBHs in the Galactic center region with future generations of gamma-ray instruments if a blackbody-like emission of similar to 10 MeV temperature would be detected by them. SMMBHs can be a potential candidate for the dark ( invisible) matter halo. C1 George Mason Univ, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA. USN, Res Lab, Washington, DC 20375 USA. NASA, Goddard Space Flight Ctr, USRA Code 660, Greenbelt, MD 20771 USA. Univ Savoie, LAPTH, LAPP, F-74941 Annecy Le Vieux, France. RP Titarchuk, L (reprint author), George Mason Univ, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA. EM ltitarchuk@ssd5.nrl.navy.mil; chardonnet@lapp.in2p3.fr NR 84 TC 19 Z9 19 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2006 VL 641 IS 1 BP 293 EP 301 DI 10.1086/499394 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AH UT WOS:000236817800023 ER PT J AU Gibb, EL Rettig, TW Brittain, SD Wasikowski, D Simon, T Vacca, WD Cushing, MC Kulesa, C AF Gibb, EL Rettig, TW Brittain, SD Wasikowski, D Simon, T Vacca, WD Cushing, MC Kulesa, C TI Post-outburst infrared spectra of V1647 Ori, the illuminating star of McNeil's nebula SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : ISM; ISM : abundances; ISM : molecules; line : profiles ID T TAURI STARS; YOUNG STARS; EMISSION-LINE; CO EMISSION; SPECTROGRAPH; IRAS-05436-0007; EXTINCTION; ABSORPTION; TELESCOPE; PROBE AB V1647 Ori is a low-mass star in the L1630 star-forming region that underwent an outburst in late 2003 and early 2004. We present postoutburst infrared spectra obtained with NIRSPEC (Keck II) and SpeX (IRTF) and compare these to spectra taken during the outburst. The results show that the temperature of the hot CO formed in the inner part of the disk has declined by similar to 800 K, while the water and CO ice and low-J CO gas features remained unchanged, consistent with previous assertions that the latter, low-temperature features arise in the foreground cloud. The P Cygni profiles of the Paschen series that were present in the outburst spectra taken in 2004 March disappeared by late 2004. The equivalent width of the helium absorption line at 1.0830 mu m decreased from 8.9 to 3.9 angstrom between 2004 March and November, evidence that the hot, fast wind has decreased substantially. We discuss the implications for categorizing V1647 Ori among the known classes of outbursting young stars. C1 Univ Missouri, St Louis, MO 63121 USA. Univ Notre Dame, Ctr Astrophys, Notre Dame, IN 46556 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. NASA, Ames Res Ctr, SOFIA, USRA, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Univ Missouri, 8001 Nat Bridge Rd, St Louis, MO 63121 USA. RI Brittain, Sean/K-9001-2012 OI Brittain, Sean/0000-0001-5638-1330 NR 26 TC 17 Z9 17 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2006 VL 641 IS 1 BP 383 EP 388 DI 10.1086/500448 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AH UT WOS:000236817800030 ER PT J AU Millan-Gabet, R Monnier, JD Akeson, RL Hartmann, L Berger, JP Tannirkulam, A Melnikov, S Billmeier, R Calvet, N D'Alessio, P Hillenbrand, LA Kuchner, M Traub, WA Tuthill, PG Beichman, C Boden, A Booth, A Colavita, M Creech-Eakman, M Gathright, J Hrynevych, M Koresko, C Le Mignant, D Ligon, R Mennesson, B Neyman, C Sargent, A Shao, M Swain, M Thompson, R Unwin, S van Belle, G Vasisht, G Wizinowich, P AF Millan-Gabet, R Monnier, JD Akeson, RL Hartmann, L Berger, JP Tannirkulam, A Melnikov, S Billmeier, R Calvet, N D'Alessio, P Hillenbrand, LA Kuchner, M Traub, WA Tuthill, PG Beichman, C Boden, A Booth, A Colavita, M Creech-Eakman, M Gathright, J Hrynevych, M Koresko, C Le Mignant, D Ligon, R Mennesson, B Neyman, C Sargent, A Shao, M Swain, M Thompson, R Unwin, S van Belle, G Vasisht, G Wizinowich, P TI Keck interferometer observations of FU Orionis objects SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; instrumentation : interferometers; planetary systems : protoplanetary disks; stars : formation; stars : individual ( V1057 Cygnus, V1515 Cygnus, Z Canis Majoris); techniques : high angular resolution ID Z-CANIS-MAJORIS; HERBIG AE/BE STARS; YOUNG STELLAR OBJECTS; T-TAURI STARS; PALOMAR TESTBED INTERFEROMETER; CIRCUMSTELLAR STRUCTURE; INFRARED-EMISSION; DISK MODELS; ACCRETION; SPECTROSCOPY AB We present new K-band long-baseline interferometer observations of three young stellar objects of the FU Orionis class, namely, V1057 Cyg, V1515 Cyg, and Z CMa-SE, obtained at the Keck Interferometer during its commissioning science period. The interferometer clearly resolves the source of near-infrared emission in all three objects. Using simple geometric models, we derive size scales (0.5-4.5 AU) for this emission. All three objects appear significantly more resolved than expected from simple models of accretion disks tuned to fit the broadband optical and infrared spectrophotometry. We explore variations in the key parameters that are able to lower the predicted visibility amplitudes to the measured levels and conclude that accretion disks alone do not reproduce the spectral energy distributions and K-band visibilities simultaneously. We conclude that either disk models are inadequate to describe the near-infrared emission or additional source components are needed. We hypothesize that large-scale emission ( tens of AU) in the interferometer field of view is responsible for the surprisingly low visibilities. This emission may arise in scattering by large envelopes believed to surround these objects. C1 CALTECH, Michelson Sci Ctr, Pasadena, CA 91125 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lab Astrophys Grenoble, F-38400 St Martin Dheres, France. Ulugh Beg Astron Inst, Tashkent 700052, Uzbekistan. Univ Nacl Autonoma Mexico, Mexico City 04510, DF, Mexico. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Sydney, Dept Phys, Sydney, NSW 2006, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Calif Assoc Res Astron, WM Keck Observ, Kamuela, HI 96743 USA. RP CALTECH, Michelson Sci Ctr, Mail Stop 100-22, Pasadena, CA 91125 USA. EM rafael@ipac.caltech.edu RI Kuchner, Marc/E-2288-2012 NR 62 TC 28 Z9 28 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2006 VL 641 IS 1 BP 547 EP 555 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AH UT WOS:000236817800046 ER PT J AU Bhattacharyya, S Strohmayer, TE AF Bhattacharyya, S Strohmayer, TE TI Signature of temporary burning front stalling from a non-photospheric radius expansion double-peaked burst SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; relativity; stars : neutron; X-rays : binaries; X-rays : bursts; X-rays : individual (4U 1636-536) ID X-RAY-BURSTS; ROTATING NEUTRON-STARS; FREQUENCY EVOLUTION; MILLISECOND PULSAR; 4U 1636-53; OSCILLATIONS; PROFILES AB Non-photospheric radius expansion (non-PRE) double-peaked bursts may be explained in terms of spreading ( and temporary stalling) of thermonuclear flames on the neutron star surface, as we argued in a previous study of a burst assuming polar ignition. Here we analyze Rossi X-Ray Timing Explorer ( RXTE) Proportional Counter Array (PCA) data of such a burst (but with a considerably different intensity profile from the previous one) from the low-mass X-ray binary (LMXB) system 4U 1636 - 536 and show that this model can qualitatively explain the observed burst profile and spectral evolution, if we assume an off-polar, but high-latitude, ignition and burning front stalling at a higher latitude compared to that for the previous burst. The off-polar ignition can account for the millisecond period brightness oscillations detected from this burst. This is the first time oscillations have been seen from such a burst. Our model can qualitatively explain the oscillation amplitude measured during the first ( weaker) peak and the absence of oscillations during the second peak. The higher latitude front stalling facilitates the first clear detection of a signature of this stalling, which is the primary result of this work, and may be useful for understanding thermonuclear flame spreading on neutron stars. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Explorat Universe Div, Greenbelt, MD 20771 USA. RP Bhattacharyya, S (reprint author), Univ Maryland, Dept Astron, College Pk, MD 20742 USA. EM sudip@milkyway.gsfc.nasa.gov; stroh@clarence.gsfc.nasa.gov NR 20 TC 19 Z9 19 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2006 VL 641 IS 1 BP L53 EP L56 DI 10.1086/503768 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AK UT WOS:000236818100014 ER PT J AU Brosius, JW White, SM AF Brosius, JW White, SM TI Radio measurements of the height of strong coronal magnetic fields above sunspots at the solar limb SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : activity; Sun : corona; Sun : magnetic fields; Sun : radio radiation; sunspots; Sun : UV radiation ID EXTREME-ULTRAVIOLET OBSERVATIONS; DIAGNOSTIC-SPECTROMETER; ACTIVE-REGION; ATOMIC DATABASE; EMISSION-LINES; TELESCOPE; PLUME; SOHO; VLA; STEREOSCOPY AB We measure coronal magnetic field strengths of 1750 G at a height of 8000 km above a large sunspot in NOAA AR 10652 at the west solar limb on 2004 July 29 using coordinated observations with the Very Large Array, the Transition Region and Coronal Explorer, and three instruments (CDS, EIT, MDI) aboard the Solar and Heliospheric Observatory. This observation is the first time that coronal radio brightness temperatures have been analyzed in a 15 GHz solar radio source projected above the limb. Observations at 8 GHz yield coronal magnetic field strengths of 960 G at a height of 12,000 km. The field strength measurements combine to yield a magnetic scale height km. The radio brightness temperature maxima are located away from a sunspot plume that appears bright in EUV line emission formed at temperatures around several x 10(5) K. We use the density-sensitive emission-line intensity ratio of 0 iv 625.8 angstrom/554.5 angstrom to derive an electron density n(e) (in units of cm(-3)) of log n(e) = 10.1 +/- 0.2 at the base of the plume. C1 Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Code 612-1, Greenbelt, MD 20771 USA. EM brosius@comstoc.gsfc.nasa.gov; white@astro.umd.edu NR 42 TC 29 Z9 29 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2006 VL 641 IS 1 BP L69 EP L72 DI 10.1086/503774 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AK UT WOS:000236818100018 ER PT J AU Quillen, AC Bland-Hawthorn, J Brookes, MH Werner, MW Smith, JD Stern, D Keene, J Lawrence, CR AF Quillen, AC Bland-Hawthorn, J Brookes, MH Werner, MW Smith, JD Stern, D Keene, J Lawrence, CR TI Discovery of A 500 parsec shell in the nucleus of Centaurus A SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (NGC 5128); galaxies : ISM; galaxies : structure; ISM : bubbles; ISM : jets and outflows ID X-RAY-EMISSION; SPACE-TELESCOPE; INTERSTELLAR-MEDIUM; VLA OBSERVATIONS; STAR-FORMATION; NGC 5128; GALAXIES; ABSORPTION; WIND; DISK AB Spitzer Space Telescope mid-infrared images of the radio galaxy Centaurus A reveal a shell-like, bipolar, structure 500 pc to the north and south of the nucleus. This shell is seen in 5.8, 8.0, and 24 mu m broadband images. Such a remarkable shell has not been previously detected in a radio galaxy and, if confirmed, would be the first extragalactic nuclear shell detected at mid-infrared wavelengths. Assuming that it is a coherent expanding structure, we estimate that the shell is a few million years old and has a mass on the order of a million solar masses. A conservative estimate for the mechanical energy in the wind-driven bubble is 1053 ergs. The shell could have been created by a small, few-thousand solar mass, nuclear burst of star formation. Alternatively, the bolometric luminosity of the active nucleus is sufficiently large that it could power the shell. Constraints on the shell's velocity are lacking. However, if the shell is moving at 1000 km s(-1), then the required mechanical energy would be 100 times larger. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Anglo Australian Observ, Epping, NSW 1710, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Univ Rochester, Dept Phys & Astron, 601 Elmwood Ave, Rochester, NY 14627 USA. EM aquillen@pas.rochester.edu; jbh@aao.gov.au NR 41 TC 11 Z9 12 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2006 VL 641 IS 1 BP L29 EP L32 DI 10.1086/503670 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033AK UT WOS:000236818100008 ER PT J AU Roden, JC King, BW Trout, D Mortazavi, A Wold, BJ Hart, CE AF Roden, Joseph C. King, Brandon W. Trout, Diane Mortazavi, Ali Wold, Barbara J. Hart, Christopher E. TI Mining gene expression data by interpreting principal components SO BMC BIOINFORMATICS LA English DT Article ID MICROARRAY DATA; CLUSTERING ANALYSIS; PATTERNS; CLASSIFICATION; TUMOR; ALGORITHM; NETWORK; CANCER; YEAST AB Background: There are many methods for analyzing microarray data that group together genes having similar patterns of expression over all conditions tested. However, in many instances the biologically important goal is to identify relatively small sets of genes that share coherent expression across only some conditions, rather than all or most conditions as required in traditional clustering; e. g. genes that are highly up-regulated and/or down-regulated similarly across only a subset of conditions. Equally important is the need to learn which conditions are the decisive ones in forming such gene sets of interest, and how they relate to diverse conditional covariates, such as disease diagnosis or prognosis. Results: We present a method for automatically identifying such candidate sets of biologically relevant genes using a combination of principal components analysis and information theoretic metrics. To enable easy use of our methods, we have developed a data analysis package that facilitates visualization and subsequent data mining of the independent sources of significant variation present in gene microarray expression datasets (or in any other similarly structured high-dimensional dataset). We applied these tools to two public datasets, and highlight sets of genes most affected by specific subsets of conditions ( e. g. tissues, treatments, samples, etc.). Statistically significant associations for highlighted gene sets were shown via global analysis for Gene Ontology term enrichment. Together with covariate associations, the tool provides a basis for building testable hypotheses about the biological or experimental causes of observed variation. Conclusion: We provide an unsupervised data mining technique for diverse microarray expression datasets that is distinct from major methods now in routine use. In test uses, this method, based on publicly available gene annotations, appears to identify numerous sets of biologically relevant genes. It has proven especially valuable in instances where there are many diverse conditions ( 10's to hundreds of different tissues or cell types), a situation in which many clustering and ordering algorithms become problematic. This approach also shows promise in other topic domains such as multi-spectral imaging datasets. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. CALTECH, Div Biol, Pasadena, CA 91125 USA. RP Roden, JC (reprint author), CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. EM joe.roden@jpl.nasa.gov; kingb@caltech.edu; diane@caltech.edu; alim@caltech.edu; woldb@caltech.edu; hart@caltech.edu NR 30 TC 28 Z9 29 U1 0 U2 4 PU BIOMED CENTRAL LTD PI LONDON PA MIDDLESEX HOUSE, 34-42 CLEVELAND ST, LONDON W1T 4LB, ENGLAND SN 1471-2105 J9 BMC BIOINFORMATICS JI BMC Bioinformatics PD APR 7 PY 2006 VL 7 AR 194 DI 10.1186/1471-2105-7-194 PG 22 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Mathematical & Computational Biology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Mathematical & Computational Biology GA 062YY UT WOS:000238984100001 PM 16600052 ER PT J AU Robertson, NA Blackwood, JR Buchman, S Byer, RL Camp, J Gill, D Hanson, J Williams, S Zhou, P AF Robertson, NA Blackwood, JR Buchman, S Byer, RL Camp, J Gill, D Hanson, J Williams, S Zhou, P TI Kelvin probe measurements: investigations of the patch effect with applications to ST-7 and LISA SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article ID POTENTIALS AB One of the possible noise sources for the space-based gravitational wave detector LISA (the Laser Interferometer' Space Antenna), associated with its test masses, is that due to spatial variations in surface potential (or patch effect) across the surfaces of the test mass and its housing. Such variations will lead to force gradients which may result in a significant acceleration noise term. Another noise source is that due to temporal variations in the surface potential, which in conjunction with any ambient dc voltage or net free charge on the test mass may also produce a significant acceleration noise term. The ST-7 demonstrator mission is designed to test technologies for LISA, including the gravitational reference sensor, which contains a gold-coated gold/platinum (Au/Pt) alloy test mass, surrounded by a housing that carries the electrodes for sensing and control. We have used a Kelvin probe at the Goddard Space Flight Center to make spatial and temporal measurements of contact potential differences for a selection of materials (Au/Pt, beryllia, alumina, titanium) and coatings (gold, diamond-like carbon, indium tin oxide, titanium carbide). Our investigations indicate that subject to certain assumptions all of these coatings appear to satisfy the ST-7 requirement that patch effect spatial variations should be less than 100 mV. The data also revealed evidence of behavioural trends with pressure and possible contamination effects. Regarding temporal variations, the current accuracy of the instrument is limiting the measurements at a level above the likely LISA requirements. We discuss our results and draw some conclusions of relevance to LISA. C1 Stanford Univ, Hanson Expt Phys Lab, Stanford, CA 94305 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Robertson, NA (reprint author), Stanford Univ, Hanson Expt Phys Lab, Stanford, CA 94305 USA. NR 12 TC 34 Z9 34 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD APR 7 PY 2006 VL 23 IS 7 BP 2665 EP 2680 DI 10.1088/0264-9381/23/7/026 PG 16 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 034MI UT WOS:000236932700026 ER PT J AU Cowley, SWH Wright, DM Bunce, EJ Carter, AC Dougherty, MK Giampieri, G Nichols, JD Robinson, TR AF Cowley, SWH Wright, DM Bunce, EJ Carter, AC Dougherty, MK Giampieri, G Nichols, JD Robinson, TR TI Cassini observations of planetary-period magnetic field oscillations in Saturn's magnetosphere: Doppler shifts and phase motion SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ROTATION PERIOD; PERTURBATIONS; RADIO; ORBIT; MODEL AB Cassini magnetic field observations show that few-nT oscillations near the planetary rotation period, first observed in Pioneer-11 and Voyager-1 and - 2 fly-by data, are essentially ubiquitous in Saturn's magnetosphere, though their character differs between the quasi-dipolar ring current region and the dawn tail. Examination of data from the ring-current region shows, however, that the observed oscillation period is not fixed at the planetary period, but has smaller values on the inbound pass of the spacecraft, increasing to larger values at and beyond periapsis. These variations are shown to be consistent with the Doppler shifts due to spacecraft motion expected in a model in which the wave phase fronts rotate with the planet, and radiate outward at a speed comparable with the equatorial Alfven speed. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2AZ, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Cowley, SWH (reprint author), Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. EM swhc1@ion.le.ac.uk RI Nichols, Jonathan/F-5764-2010; Bunce, Emma/I-9067-2016 OI Nichols, Jonathan/0000-0002-8004-6409; Bunce, Emma/0000-0002-9456-0345 NR 13 TC 59 Z9 59 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 7 PY 2006 VL 33 IS 7 AR L07104 DI 10.1029/2005GL025522 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 033VI UT WOS:000236878800005 ER PT J AU Miloshevich, LM Vomel, H Whiteman, DN Lesht, BM Schmidlin, FJ Russo, F AF Miloshevich, LM Vomel, H Whiteman, DN Lesht, BM Schmidlin, FJ Russo, F TI Absolute accuracy of water vapor measurements from six operational radiosonde types launched during AWEX-G and implications for AIRS validation SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MICROWAVE RADIOMETER; LIQUID WATER; TEMPERATURE; ICE AB [1] A detailed assessment of radiosonde water vapor measurement accuracy throughout the tropospheric column is needed for assessing the impact of observational error on applications that use the radiosonde data as input, such as forecast modeling, radiative transfer calculations, remote sensor retrieval validation, climate trend studies, and development of climatologies and cloud and radiation parameterizations. Six operational radiosonde types were flown together in various combinations with a reference-quality hygrometer during the Atmospheric Infrared Sounder ( AIRS) Water Vapor Experiment-Ground (AWEX-G), while simultaneous measurements were acquired from Raman lidar and microwave radiometers. This study determines the mean accuracy and variability of the radiosonde water vapor measurements relative to simultaneous measurements from the University of Colorado (CU) Cryogenic Frostpoint Hygrometer (CFH), a reference-quality standard of known absolute accuracy. The accuracy and performance characteristics of the following radiosonde types are evaluated: Vaisala RS80-H, RS90, and RS92; Sippican Mark IIa; Modem GL98; and the Meteolabor Snow White hygrometer. A validated correction for sensor time lag error is found to improve the accuracy and reduce the variability of upper tropospheric water vapor measurements from the Vaisala radiosondes. The AWEX data set is also used to derive and validate a new empirical correction that improves the mean calibration accuracy of Vaisala measurements by an amount that depends on the temperature, relative humidity, and sensor type. Fully corrected Vaisala radiosonde measurements are found to be suitably accurate for AIRS validation throughout the troposphere, whereas the other radiosonde types are suitably accurate under only a subset of tropospheric conditions. Although this study focuses on the accuracy of nighttime radiosonde measurements, comparison of Vaisala RS90 measurements to water vapor retrievals from a microwave radiometer reveals a 6 - 8% dry bias in daytime RS90 measurements that is caused by solar heating of the sensor. An AWEX-like data set of daytime measurements is highly desirable to complete the accuracy assessment, ideally from a tropical location where the full range of tropospheric temperatures can be sampled. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. Argonne Natl Lab, Dept Energy, Argonne, IL 60439 USA. RP Miloshevich, LM (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM milo@ucar.edu OI Lesht, Barry/0000-0003-0801-4290 NR 30 TC 159 Z9 160 U1 2 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 7 PY 2006 VL 111 IS D9 AR D09S10 DI 10.1029/2005JD006083 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 033WB UT WOS:000236881300001 ER PT J AU Laird, JS Jagadish, C Jamieson, DN Legge, GJF AF Laird, JS Jagadish, C Jamieson, DN Legge, GJF TI Scanning ion deep level transient spectroscopy: I. Theory SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID HIGH-SPEED PHOTODETECTORS; CHARGE COLLECTION; SILICON; SEMICONDUCTORS; DETECTORS; INJECTION; SI; RECOMBINATION; PERFORMANCE; DEPENDENCE AB Theoretical aspects of a new technique for the MeV ion microbeam are described in detail for the first time. The basis of the technique, termed scanning ion deep level transient spectroscopy (SIDLTS), is the imaging of defect distributions within semiconductor devices. The principles of SIDLTS are similar to those behind other deep level transient spectroscopy (DLTS) techniques with the main difference stemming from the injection of carriers into traps using the localized energy-loss of a focused MeV ion beam. Energy-loss of an MeV ion generates an electron-hole pair plasma, providing the equivalent of a DLTS trap filling pulse with a duration which depends on space-charge screening of the applied electric field and ambipolar erosion of the plasma for short ranging ions. Some nanoseconds later, the detrapping current transient is monitored as a charge transient. Scanning the beam in conjunction with transient analysis allows the imaging of defect levels. As with DLTS, the temperature dependence of the transient can be used to extract trap activation levels. In this, the first of a two-part paper, we introduce the various stages of corner capture and derive a simple expression for the observed charge transient. The second paper will illustrate the technique on a MeV ion implanted Au-Si Schottky junction. C1 Univ Melbourne, Sch Phys, MARC, Parkville, Vic 3052, Australia. Australian Natl Univ, RSPSE, Canberra, ACT, Australia. RP CALTECH, Jet Prop Lab, NASA, Radiat Effects Grp, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Jaimie.S.Laird@jpl.nasa.gov RI Jamieson, David/G-3753-2010; OI Jamieson, David/0000-0001-7733-6715 NR 55 TC 10 Z9 10 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 EI 1361-6463 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD APR 7 PY 2006 VL 39 IS 7 BP 1342 EP 1351 DI 10.1088/0022-3727/39/7/003 PG 10 WC Physics, Applied SC Physics GA 038JX UT WOS:000237216900011 ER PT J AU Laird, JS Jagadish, C Jamieson, DN Legge, GJF AF Laird, JS Jagadish, C Jamieson, DN Legge, GJF TI Scanning ion deep level transient spectroscopy: II. Ion irradiated Au-Si Schottky junctions SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID SILICON DETECTOR MATERIAL; READ-HALL LIFETIME; N-TYPE SILICON; POINT-DEFECTS; TEMPERATURE-DEPENDENCE; INJECTION DEPENDENCE; CRYSTALLINE SILICON; ELECTRON; SEMICONDUCTORS; RECOMBINATION AB Here we introduce a new technique called scanning ion deep level transient spectroscopy (SIDLTS) for the spatial analysis of electrically active defects in devices. In the first part of this paper, a simple theory behind SIDLTS was introduced and factors determining its sensitivity and resolution were discussed. In this paper, we demonstrate the technique on MeV boron implantation induced defects in an Au-Si Schottky junction. SIDLTS measurements are compared with capacitance DLTS measurements over the temperature range, 100-300 K. SIDLTS analyses indicate the presence of two levels, one of which was positively identified as the E-c -0.23 eV divacancy level. The high sensitivity of SIDLTS is verified and the advantages and limitations of the technique are discussed in light of non-exponential components in the charge transient response. Reasons for several undetected levels are also discussed. C1 Univ Melbourne, Sch Phys, MARC, Parkville, Vic, Australia. Australian Natl Univ, RSPSE, Canberra, ACT, Australia. RP CALTECH, Jet Prop Lab, Radiat Effect Grp, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Jamie.S.Laird@jpl.nasa.gov RI Jamieson, David/G-3753-2010; OI Jamieson, David/0000-0001-7733-6715 NR 48 TC 6 Z9 6 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 EI 1361-6463 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD APR 7 PY 2006 VL 39 IS 7 BP 1352 EP 1362 DI 10.1088/0022-3727/39/7/004 PG 11 WC Physics, Applied SC Physics GA 038JX UT WOS:000237216900012 ER PT J AU Shuman, CA Zwally, HJ Schutz, BE Brenner, AC DiMarzio, JP Suchdeo, VP Fricker, HA AF Shuman, CA Zwally, HJ Schutz, BE Brenner, AC DiMarzio, JP Suchdeo, VP Fricker, HA TI ICESat Antarctic elevation data: Preliminary precision and accuracy assessment SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Since 'first light' on February 20th, 2003, NASA's Ice, Cloud, and land Elevation Satellite (ICESat) has derived surface elevations from similar to 86 degrees N to 86 degrees S latitude. These unique altimetry data have been acquired in a series of observation periods in repeated track patterns using all three Geoscience Laser Altimeter System (GLAS) lasers. Here, we focus on Antarctic ice sheet elevation data that were obtained in 2003-2004. We present preliminary precision and accuracy assessments of selected elevation data, and discuss factors impacting elevation change detection. We show that for low slope and clear sky conditions, the precision of GLA12 Laser 2a, Release 21 data is similar to 2.1 cm and the relative accuracy of ICESat elevations is +/- 14 cm based on crossover differences. C1 NASA, Goddard Space Flight Ctr, Cryospher Sci Branch, Greenbelt, MD 20771 USA. Univ Texas, Ctr Space Res, Austin, TX 78759 USA. NASA, Goddard Space Flight Ctr, SSAI, Lanham, MD 20706 USA. SGT Inc, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NVI Inc, NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. RP Shuman, CA (reprint author), NASA, Goddard Space Flight Ctr, Cryospher Sci Branch, Code 614-1, Greenbelt, MD 20771 USA. EM christopher.a.shuman@nasa.gov NR 13 TC 82 Z9 87 U1 1 U2 21 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 6 PY 2006 VL 33 IS 7 AR L07501 DI 10.1029/2005GL025227 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 033VH UT WOS:000236878600002 ER PT J AU Farrell, WM Desch, MD Kaiser, ML Kurth, WS Gurnett, DA AF Farrell, WM Desch, MD Kaiser, ML Kurth, WS Gurnett, DA TI Changing electrical nature of Saturn's rings: Implications for spoke formation SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PLASMA; SYSTEM; MODEL AB During Cassini's orbit insertion at Saturn, the trajectory took the spacecraft overtop the planet's famed ring system. At this time, the Cassini Radio and Plasma Wave Science (RPWS) instrument obtained unprecedented observations of electron density in the vicinity of the rings. Using this information and a model of photoemission anticipated from the rings, we demonstrate that the ring surface potential undergoes a seasonal change in electrical configuration, being primarily unipolar ( of one charge polarity/potential) during the Voyager era and now bipolar ( two separate polarities/potentials) during the Cassini era. We calculate the approximate ring/sun opening angle required for the transition from unipolar to bipolar configuration. Using electron density profiles, we explicitly examine the conditions for current balance on the B ring and show which regions are most likely to charge to positive potentials and those that may remain negative as a function of ring opening angle relative to the sun. Finally, we demonstrate that the current body of observations of Saturn ring spokes is consistent with their formation only on negatively-charged surfaces, and suggest future times and locations to look for spoke activity based upon the model. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. RP Farrell, WM (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM william.farrell@gsfc.nasa.gov RI Farrell, William/I-4865-2013; OI Kurth, William/0000-0002-5471-6202 NR 16 TC 4 Z9 4 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 5 PY 2006 VL 33 IS 7 AR L07203 DI 10.1029/2005GL024922 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 033VF UT WOS:000236878400002 ER PT J AU Fletcher, SEM Gruber, N Jacobson, AR Doney, SC Dutkiewicz, S Gerber, M Follows, M Joos, F Lindsay, K Menemenlis, D Mouchet, A Muller, SA Sarmiento, JL AF Fletcher, SEM Gruber, N Jacobson, AR Doney, SC Dutkiewicz, S Gerber, M Follows, M Joos, F Lindsay, K Menemenlis, D Mouchet, A Muller, SA Sarmiento, JL TI Inverse estimates of anthropogenic CO2 uptake, transport, and storage by the ocean SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article ID PAST 2 CENTURIES; ATLANTIC-OCEAN; INORGANIC CARBON; ATMOSPHERIC CO2; NORTH-ATLANTIC; PACIFIC-OCEAN; BULK DATA; AIR; FLUXES; WATER AB [1] Regional air-sea fluxes of anthropogenic CO2 are estimated using a Green's function inversion method that combines data-based estimates of anthropogenic CO2 in the ocean with information about ocean transport and mixing from a suite of Ocean General Circulation Models (OGCMs). In order to quantify the uncertainty associated with the estimated fluxes owing to modeled transport and errors in the data, we employ 10 OGCMs and three scenarios representing biases in the data-based anthropogenic CO2 estimates. On the basis of the prescribed anthropogenic CO2 storage, we find a global uptake of 2.2 +/- 0.25 Pg C yr(-1), scaled to 1995. This error estimate represents the standard deviation of the models weighted by a CFC-based model skill score, which reduces the error range and emphasizes those models that have been shown to reproduce observed tracer concentrations most accurately. The greatest anthropogenic CO2 uptake occurs in the Southern Ocean and in the tropics. The flux estimates imply vigorous northward transport in the Southern Hemisphere, northward cross-equatorial transport, and equatorward transport at high northern latitudes. Compared with forward simulations, we find substantially more uptake in the Southern Ocean, less uptake in the Pacific Ocean, and less global uptake. The large-scale spatial pattern of the estimated flux is generally insensitive to possible biases in the data and the models employed. However, the global uptake scales approximately linearly with changes in the global anthropogenic CO2 inventory. Considerable uncertainties remain in some regions, particularly the Southern Ocean. C1 Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA 90024 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. Princeton Univ, Princeton, NJ 08544 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. Univ Bern, Inst Phys, CH-3012 Bern, Switzerland. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Liege, Astrophys & Geophys Inst, B-4000 Liege, Belgium. RP Fletcher, SEM (reprint author), Princeton Univ, Sayre Hall,Forrestal Campus,POB CN710, Princeton, NJ 08544 USA. EM sara@splash.princeton.edu; ngruber@igpp.ucla.edu; andyj@splash.princeton.edu; sdoney@whoi.edu; stephd@ocean.mit.edu; mgerber@climate.unibe.ch; mick@ocean.mit.edu; joos@climate.unibe.ch; klindsay@ucar.edu; menemenlis@jpl.nasa.gov; a.mouchet@ulg.ac.be; smueller@climate.unibe.ch; jls@princeton.edu RI Gruber, Nicolas/B-7013-2009; Follows, Michael/G-9824-2011; Doney, Scott/F-9247-2010; Mouchet, Anne/K-1911-2014; OI Gruber, Nicolas/0000-0002-2085-2310; Doney, Scott/0000-0002-3683-2437; Mouchet, Anne/0000-0002-8846-3063; Mikaloff Fletcher, Sara/0000-0003-0741-0320 NR 54 TC 161 Z9 161 U1 8 U2 47 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 EI 1944-9224 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD APR 5 PY 2006 VL 20 IS 2 AR GB2002 DI 10.1029/2005GB002530 PG 16 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 033VO UT WOS:000236879500002 ER PT J AU Yan, L Park, C Ounaies, Z Irene, EA AF Yan, L Park, C Ounaies, Z Irene, EA TI An ellipsometric study of polymer film curing: 2,6-Bis(3-aminophenoxy) benzonitrile/4,4 ' oxidiphthalic anhydride poly(amic acid) SO POLYMER LA English DT Article DE polymer curing; spectroscopic ellipsometry; real-time monitoring ID AROMATIC POLYIMIDES; ULTRAVIOLET-ABSORPTION; ELECTRONIC-STRUCTURE; CHARGE-TRANSFER; IMIDIZATION AB The curing of 2,6-bis(3-aminophenoxy)benzonitrile/4,4'oxidiphthalic anhydride ((beta-CN) APB/ODPA) has been investigated using spectroscopic ellipsometry on films with various degrees of imidization. Results indicate that much of the film imidization is accomplished at 200 degrees C and above. Three absorption peaks have been observed (4 1, 5, and 6 eV) which correspond to intra- and inter-molecular optical transitions. A comparison of the film optical constants for the pristine poly(amic acid) and the fully cured polyimide shows film densification upon imidization. A curing timeline has been obtained using in situ real-time spectroscopic ellipsometry. and ellipsometry is shown to serve as a general technique for studying organic film curing. (c) 2006 Elsevier Ltd. All rights reserved. C1 Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. NASA, Langley Res Ctr, Natl Inst Aerosp, Hampton, VA 23681 USA. Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. RP Irene, EA (reprint author), Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. EM gene_irene@unc.edu NR 28 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD APR 5 PY 2006 VL 47 IS 8 BP 2822 EP 2829 DI 10.1016/j.polymer.2006.02.056 PG 8 WC Polymer Science SC Polymer Science GA 033AG UT WOS:000236817700027 ER PT J AU Brown, SR Kauzlarich, SM Gascoin, F Snyder, GJ AF Brown, SR Kauzlarich, SM Gascoin, F Snyder, GJ TI Yb14MnSb11: New high efficiency thermoelectric material for power generation SO CHEMISTRY OF MATERIALS LA English DT Article ID TRANSPORT-PROPERTIES; ZINTL COMPOUNDS; YB14ZNSB11; TL9BITE6; FIGURES; MERIT AB Thermoelectric materials provide a key solution to energy problems through the conversion of heat into electrical energy. We report that the complex Zintl compound, Yb14MnSb11, breaks a 2-decade stagnation in high-temperature (> 900 K), p-type materials development for thermoelectric power generation. This material achieves quadrupled efficiency and virtually doubled figure of merit over the current state-of-the-art, SiGe, thus earmarking it superior for thermoelectric applications in segmented devices. Yb14MnSb11 represents the first complex Zintl phase with substantially higher figure of merit and efficiency than any other competing materials, opening a new class of thermoelectric compounds with remarkable chemical and physical properties. C1 Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kauzlarich, SM (reprint author), Univ Calif Davis, Dept Chem, 1 Shields Ave, Davis, CA 95616 USA. EM smkauzlarich@ucdavis.edu; jsnyder@jpl.nasa.gov RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; NR 32 TC 339 Z9 342 U1 22 U2 169 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD APR 4 PY 2006 VL 18 IS 7 BP 1873 EP 1877 DI 10.1021/cm060261t PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 028PC UT WOS:000236499300023 ER PT J AU Mlynczak, MG Johnson, DG Latvakoski, H Jucks, K Watson, M Kratz, DP Bingham, G Traub, WA Wellard, SJ Hyde, CR Liu, X AF Mlynczak, MG Johnson, DG Latvakoski, H Jucks, K Watson, M Kratz, DP Bingham, G Traub, WA Wellard, SJ Hyde, CR Liu, X TI First light from the Far-Infrared Spectroscopy of the Troposphere (FIRST) instrument SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MICHELSON INTERFEROMETER; SPECTROMETER; SYSTEM; EARTH; CLOUDS AB We present first light spectra that were measured by the newly-developed Far-Infrared Spectroscopy of the Troposphere ( FIRST) instrument during a high-altitude balloon flight from Ft. Sumner, NM on 7 June 2005. FIRST is a Fourier Transform Spectrometer designed to measure accurately the far-infrared ( 15 to 100 mm; 650 to 100 wavenumbers, cm(-1)) emission spectrum of the Earth and its atmosphere. The flight data successfully demonstrated the FIRST instrument's ability to observe the entire energetically significant infrared emission spectrum ( 50 to 2000 cm(-1)) at high spectral and spatial resolution on a single focal plane in an instrument with one broad spectral bandpass beamsplitter. Comparisons with radiative transfer calculations demonstrate that FIRST accurately observes the very fine spectral structure in the far-infrared. Comparisons also show excellent agreement between the atmospheric window radiance measured by FIRST and by instruments on the NASA Aqua satellite that overflew the FIRST flight. FIRST opens a new window on the spectrum that can be used for studying atmospheric radiation and climate, cirrus clouds, and water vapor in the upper troposphere. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Space Dynam Lab, Logan, UT 84341 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Mlynczak, MG (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. EM m.g.mlynczak@nasa.gov RI Mlynczak, Martin/K-3396-2012; Johnson, David/F-2376-2015 OI Johnson, David/0000-0003-4399-5653 NR 15 TC 38 Z9 38 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 4 PY 2006 VL 33 IS 7 AR L07704 DI 10.1029/2005GL025114 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 033VD UT WOS:000236878100002 ER PT J AU Mingo, N AF Mingo, N TI Thermoelectric figure of merit and maximum power factor in III-V semiconductor nanowires (vol 84, pg 2652, 2004) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP NASA, Ames Res Ctr, Ctr Nanotechnol, 299-1, Moffett Field, CA 94035 USA. NR 1 TC 18 Z9 18 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 3 PY 2006 VL 88 IS 14 AR 149902 DI 10.1063/1.2192639 PG 1 WC Physics, Applied SC Physics GA 030CX UT WOS:000236612000124 ER PT J AU Beirle, S Spichtinger, N Stohl, A Cummins, KL Turner, T Boccippio, D Cooper, OR Wenig, M Grzegorski, M Platt, U Wagner, T AF Beirle, S Spichtinger, N Stohl, A Cummins, KL Turner, T Boccippio, D Cooper, OR Wenig, M Grzegorski, M Platt, U Wagner, T TI Estimating the NO(x) produced by lightning from GOME and NLDN data: a case study in the Gulf of Mexico SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID OPTICAL TRANSIENT DETECTOR; DISPERSION MODEL FLEXPART; BOREAL FOREST-FIRES; GLOBAL DISTRIBUTION; TROPOSPHERIC NO2; UNITED-STATES; TRANSPORT; NITROGEN; OZONE; DISTRIBUTIONS AB Nitrogen oxides ( NO(x) = NO+ NO(2)) play an important role in tropospheric chemistry, in particular in catalytic ozone production. Lightning provides a natural source of nitrogen oxides, dominating the production in the tropical upper troposphere, with strong impact on tropospheric ozone and the atmosphere's oxidizing capacity. Recent estimates of lightning produced NO(x) (LNO(x)) are of the order of 5 Tg [N] per year with still high uncertainties in the range of one order of magnitude. The Global Ozone Monitoring Experiment (GOME) on board the ESA-satellite ERS-2 allows the retrieval of tropospheric column densities of NO(2) on a global scale. Here we present the GOME NO(2) measurement directly over a large convective system over the Gulf of Mexico. Simultaneously, cloud-to-ground (CG) flashes are counted by the U. S. National Lightning Detection Network ( NLDN(TM)), and extrapolated to include intra-cloud (IC)+CG flashes based on a climatological IC: CG ratio derived from NASA's space-based lightning sensors. A series of 14 GOME pixels shows largely enhanced column densities over thick and high clouds, coinciding with strong lightning activity. The enhancements can not be explained by transport of anthropogenic NO(x) and must be due to fresh production of LNO(x). A quantitative analysis, accounting in particular for the visibility of LNO(x) from satellite, yields a LNO(x) production of 90 ( 32 - 240) moles of NO(x), or 1.3 ( 0.4 - 3.4) kg [ N], per flash. If simply extrapolated, this corresponds to a global LNOx production of 1.7 ( 0.6 - 4.7) Tg [N]/yr. C1 Univ Heidelberg, Inst Umweltphys, D-6900 Heidelberg, Germany. Tech Univ Munich, Dept Ecol, D-8000 Munich, Germany. Norsk Inst Luftforskning NILU, Kjeller, Norway. Vaisala, Tucson, AZ USA. NASA, George C Marshall Space Flight Ctr, Global Hydrol & Climate Ctr, Huntsville, AL 35812 USA. NOAA, Aeron Lab, Boulder, CO 80303 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Beirle, S (reprint author), Univ Heidelberg, Inst Umweltphys, D-6900 Heidelberg, Germany. EM beirle@iup.uni-heidelberg.de RI Stohl, Andreas/A-7535-2008; Wenig, Mark/K-7279-2012; Cooper, Owen/H-4875-2013; OI Stohl, Andreas/0000-0002-2524-5755; Cummins, Kenneth/0000-0001-9871-691X NR 56 TC 38 Z9 41 U1 1 U2 8 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD APR 3 PY 2006 VL 6 BP 1075 EP 1089 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 029HH UT WOS:000236552100001 ER PT J AU Wang, L Alexander, MJ Bui, TP Mahoney, MJ AF Wang, L Alexander, MJ Bui, TP Mahoney, MJ TI Small-scale gravity waves in ER-2 MMS/MTP wind and temperature measurements during CRYSTAL-FACE SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID TROPICAL LOWER STRATOSPHERE; INTERANNUAL VARIABILITY; GENERAL-CIRCULATION; MIDDLE ATMOSPHERE; MOMENTUM FLUX; DRAG; MESOSPHERE; MODELS; PARAMETERIZATION; CONVECTION AB Lower stratospheric wind and temperature measurements made from NASA's high-altitude ER-2 research aircraft during the CRYSTAL-FACE campaign in July 2002 were analyzed to retrieve information on small scale gravity waves (GWs) at the aircraft's flight level ( typically similar to 20 km altitude). For a given flight segment, the S-transform ( a Gaussian wavelet transform) was used to search for and identify small horizontal scale GW events, and to estimate their apparent horizontal wavelengths. The horizontal propagation directions of the events were determined using the Stokes parameter method combined with the cross S-transform analysis. The vertical temperature gradient was used to determine the vertical wavelengths of the events. GW momentum fluxes were calculated from the cross S-transform. Other wave parameters such as intrinsic frequencies (omega) over cap were calculated using the GW dispersion relation. More than 100 GW events were identified. They were generally high frequency waves with vertical wavelength of similar to 5 km and horizontal wavelength generally shorter than 20 km. Their intrinsic propagation directions were predominantly toward the east, whereas their ground-based propagation directions were primarily toward the west. Among the events, similar to 20% of them had very short horizontal wavelength, very high intrinsic frequency, and relatively small momentum fluxes, and thus they were likely trapped in the lower stratosphere. Using the estimated GW parameters and the background winds and stabilities from the NCAR/NCEP reanalysis data, we were able to trace the sources of the events using a simple reverse ray-tracing. More than 70% of the events were traced back to convective sources in the troposphere, and the sources were generally located upstream of the locations of the events observed at the aircraft level. Finally, a probability density function of the reversible cooling rate due to GWs was obtained in this study, which may be useful for cirrus cloud models. C1 NW Res Associates Inc, Colorado Res Associates Div, Boulder, CO 80301 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP NW Res Associates Inc, Colorado Res Associates Div, 3380 Mitchell Lane, Boulder, CO 80301 USA. EM lwang@cora.nwra.com NR 38 TC 16 Z9 16 U1 0 U2 6 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 EI 1680-7324 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD APR 3 PY 2006 VL 6 BP 1091 EP 1104 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 029HH UT WOS:000236552100002 ER PT J AU Savchenkov, AA Matsko, AB Grudinin, I Savchenkova, EA Strekalov, D Maleki, L AF Savchenkov, AA Matsko, AB Grudinin, I Savchenkova, EA Strekalov, D Maleki, L TI Optical vortices with large orbital momentum: generation and interference SO OPTICS EXPRESS LA English DT Article ID ANGULAR-MOMENTUM; LIGHT; BEAMS AB We demonstrate a method for generation of beams of light with large angular momenta. The method utilizes whispering gallery mode resonators that transform a plane electromagnetic wave into high order Bessel beams. Interference pattern among the beams as well as shadow pictures induced by the beams are observed and studied. (c) 2006 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Moscow MV Lomonosov State Univ, Dept Phys, Moscow 119992, Russia. RP Savchenkov, AA (reprint author), CALTECH, Jet Prop Lab, MS 298-100,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Andrey.Matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 11 TC 8 Z9 8 U1 0 U2 12 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD APR 3 PY 2006 VL 14 IS 7 BP 2888 EP 2897 DI 10.1364/OE.14.002888 PG 10 WC Optics SC Optics GA 029HO UT WOS:000236552800042 PM 19516426 ER PT J AU Nakasuka, S Funase, R Nakada, K Kaya, N Mankins, JC AF Nakasuka, S Funase, R Nakada, K Kaya, N Mankins, JC TI Large membrane "Furoshiki Satellite" applied to phased array antenna and its sounding rocket experiment SO ACTA ASTRONAUTICA LA English DT Article AB University of Tokyo and Kobe University are planning a sounding rocket experiment of large membrane "Furoshiki Satellite" extension and large phased array RF transmission. The paper will describe the concept of "Furoshiki Satellite," its application to phased array antenna, and the scenario of micro gravity experiment using a small sounding rocket. University of Tokyo has been proposing the idea of "Furoshiki Satellite," a large membrane or a net structure, say I km x I km in size, extended by satellites which hold its corners. The attitude and the shape of the membrane or net structure is controlled by these corner satellites. As one application of Furoshiki Satellite, a large phased array antenna can be configured by several RF transmitters placed on several parts of the large net structure. It is difficult to control the position and attitude of the RF transmitters precisely, but using the "retro-directive" method, the tolerance of such position and attitude disturbance will be relaxed by large. This is one of promising systems' concept of the future large solar power satellite or large antenna, because quite a large area can be obtained without any hard structure, and the weight will not depend very much on the size [S. Motohashi, T. Nagamura, Large scaled membrane structure Furoshiki Satellite-its concept and orbital/attitude dynamics, in: Proceedings of 20th International Symposium on Space Technology and Science (ISTS), 1996, p. 96-n-14]. To demonstrate the feasibility of the extension of large net structure and phased array performance, micro-gravity experiment is planned using a sounding rocket of ISAS/JAXA, Japan. (c) 2006 Elsevier Ltd. All rights reserved. C1 Univ Tokyo, Dept Aeronaut & Astronaut, Bunkyo Ku, Tokyo 1138656, Japan. Kobe Univ, Dept Syst & Comp Engn, Nada Ku, Kobe, Hyogo 6578501, Japan. NASA Headquarters, Washington, DC 20546 USA. RP Nakasuka, S (reprint author), Univ Tokyo, Dept Aeronaut & Astronaut, Bunkyo Ku, HOngo 7-3-1, Tokyo 1138656, Japan. EM nakasuka@space.t.u-tokyo.ac.jp; funase@space.t.u-tokyo.ac.jp; nakada@space.t.u-tokyo.ac.jp; kaya@kobe-u.ac.jp; jmankins@hq.nasa.gov NR 8 TC 9 Z9 12 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD APR PY 2006 VL 58 IS 8 BP 395 EP 400 DI 10.1016/j.actaastro.2005.12.010 PG 6 WC Engineering, Aerospace SC Engineering GA 027LI UT WOS:000236416700003 ER PT J AU Weber, WJ Cesarone, RJ Abraham, DS Doms, PE Doyle, RJ Edwards, CD Hooke, AJ Lesh, JR Miller, RB AF Weber, WJ Cesarone, RJ Abraham, DS Doms, PE Doyle, RJ Edwards, CD Hooke, AJ Lesh, JR Miller, RB TI Transforming the deep space network into the Interplanetary Network SO ACTA ASTRONAUTICA LA English DT Article AB Space exploration missions are undergoing a significant transformation as are the expectations of their scientific investigators and the public who participate in these great voyages of exploration. The early reconnaissance missions are giving way to a new data-intensive era of long duration observational outposts, landed vehicles, sample returns, and multi-spacecraft fleets and constellations. Mars exploration has already become a special case of the new operational mode; other destinations will follow. These changes will require orders of magnitude increases in data rates, highly automated and standardized data communications between the remote locations and Earth, more transparent and responsive mission operations procedures, and the ability to engage the public by giving them Internet-based visibility into the missions as they unfold. The new area will demand a new paradigm for the Deep Space Network, with increased emphasis on data networking and the data processing applications that allow users to become more intimately engaged with the conduct of the mission. We call this new paradigm the Interplanetary Network. Its vision is seamless connectivity between scientists and their instruments, new data analysis and visualization tools that will greatly enhance and enable new modes of space exploration, and the involvement of the public via web-based "telepresence." (c) 2006 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Interplanetary Network Directorate, Pasadena, CA 91109 USA. RP Weber, WJ (reprint author), CALTECH, Jet Prop Lab, Interplanetary Network Directorate, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM William.J.Weber@jpl.nasa.gov NR 13 TC 6 Z9 7 U1 2 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD APR PY 2006 VL 58 IS 8 BP 411 EP 421 DI 10.1016/j.actaastro.2005.12.004 PG 11 WC Engineering, Aerospace SC Engineering GA 027LI UT WOS:000236416700005 ER PT J AU Grinstein, FF Liu, NS Oefelein, JC AF Grinstein, FF Liu, NS Oefelein, JC TI Introduction: Combustion modeling and large eddy simulation: Development and validation needs for gas turbines SO AIAA JOURNAL LA English DT Editorial Material C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. NASA, John H Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. Sandia Natl Labs, Livermore, CA USA. RP Grinstein, FF (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 0 TC 4 Z9 6 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2006 VL 44 IS 4 BP 673 EP 673 DI 10.2514/1.23786 PG 1 WC Engineering, Aerospace SC Engineering GA 032CS UT WOS:000236752100001 ER PT J AU Liu, NS Shih, TH AF Liu, NS Shih, TH TI Turbulence modeling for very large-eddy simulation SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 42nd Aerospace Sciences Meeting and Exhibit CY JAN 05-08, 2004 CL Reno, NV SP Amer Inst Aeronaut & Astronaut ID VISCOSITY MODEL; FLOWS AB An approach is described that attempts to bridge the gap between the traditional Reynolds-averaged Navier-Stokes (RANS) simulation and the traditional large-eddy simulation (LES). This approach affords an intermediate resolution of turbulence scales relative to those of BANS and LES and has the characteristics of the very large-eddy simulation (VLES). The very large scales of turbulence are directly calculated, and the effects of the unresolved scales are accounted for by an eddy viscosity model that is evolved from state-of-the-art models used in the RANS approach. The dependent variables and governing equations are based on a temporal filtering with a constant filter width. The contents of both resolved and unresolved scales are regulated by the width of the filter. The dependent variables and governing equations will naturally evolve from RANS to VLES and further toward LES, when the width of the temporal filter is decreased from the turbulent integral timescale to its fraction and all of the way toward the Taylor microtimescale. The subscale model uses a resolution control parameter, which is a function of the temporal filter width, to regulate the content of resolved/unresolved scales. This approach is called the partially resolved numerical simulation. Its mathematical formulation is described. Also, a guideline is provided for selecting the resolution control parameter and the grid spacing that optimizes the accuracy of the numerical simulation. Results from validation studies are then reported. C1 NASA, John H Glenn Res Ctr Lewis Field, Combust Branch, Cleveland, OH 44135 USA. RP Liu, NS (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Combust Branch, Cleveland, OH 44135 USA. NR 23 TC 14 Z9 14 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2006 VL 44 IS 4 BP 687 EP 697 DI 10.2514/1.14452 PG 11 WC Engineering, Aerospace SC Engineering GA 032CS UT WOS:000236752100003 ER PT J AU Huang, NE Brennert, MJ Salvino, L AF Huang, NE Brennert, MJ Salvino, L TI Hilbert-Huang transform stability spectral analysis applied to flutter flight test data SO AIAA JOURNAL LA English DT Article ID EMPIRICAL MODE DECOMPOSITION; SIGNALS AB A new method, the Hilbert-Huang transform (HHT), has been applied to analyze the aerostructures test wing (ATW) flight flutter data from NASA Dryden Flight Research Center. The analysis shows the yielding of the wing after the onset of flutter, but just before breaking off of the wingtip. Based on HHT, a new stability spectral analysis is also proposed that shows both positive (stable) and negative (unstable) damping. The stability spectral analysis further shows that the flutter of ATW bending occurs at 2-5 Hz in addition to 18 Hz as determined by modal analysis and identification: Both HHT and the Teager energy operator based nonlinearity indicator show that the vibrations of the ATW are nonlinear throughout the flight-test flutter maneuver. C1 NASA, Goddard Space Flight Ctr, Lab Hydrospher & Biospher Proc, Greenbelt, MD 20771 USA. NASA, Dryden Flight Res Ctr, Aerostruct Branch, Edwards AFB, CA 93523 USA. USN, Ctr Surface Warfare, Carderock Div, Carderock, MD 20854 USA. RP Huang, NE (reprint author), NASA, Goddard Space Flight Ctr, Lab Hydrospher & Biospher Proc, Code 614-2, Greenbelt, MD 20771 USA. NR 27 TC 5 Z9 5 U1 1 U2 10 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2006 VL 44 IS 4 BP 772 EP 786 DI 10.2514/1.11501 PG 15 WC Engineering, Aerospace SC Engineering GA 032CS UT WOS:000236752100010 ER PT J AU Nielsen, EJ Kleb, WL AF Nielsen, EJ Kleb, WL TI Efficient construction of discrete adjoint operators on unstructured grids using complex variables SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 43rd Aerospace Sciences Meeting and Exhibit CY JAN 10-13, 2005 CL Reno, NV SP AIAA ID AERODYNAMIC DESIGN OPTIMIZATION; TURBULENT FLOWS; MESHES; FORMULATION; ALGORITHM; EQUATIONS; IMPLICIT AB A methodology is developed and implemented to mitigate the lengthy software development cycle typically associated with constructing a discrete adjoint solver for aerodynamic simulations. The approach is based on a complex-variable formulation that enables straightforward differentiation of complicated real-valued functions. An automated scripting process is used to create the complex-variable form of the set of discrete equations. An efficient method for assembling the residual and cost function linearizations is developed. The accuracy of the implementation is verified through comparisons with a discrete direct method as well as a previously developed handcoded discrete adjoint approach. Comparisons are also shown for a large-scale configuration to establish the computational efficiency of the present scheme. To ultimately demonstrate the power of the approach. the implementation is extended to high-temperature gas flows in chemical nonequilibrium. Finally, several fruitful research and development avenues enabled by the current work are suggested. C1 NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. RP Nielsen, EJ (reprint author), NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, MS 128, Hampton, VA 23681 USA. NR 56 TC 13 Z9 13 U1 0 U2 0 PU AMER INST AERONAUTICS ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 EI 1533-385X J9 AIAA J JI AIAA J. PD APR PY 2006 VL 44 IS 4 BP 827 EP 836 DI 10.2514/1.15830 PG 10 WC Engineering, Aerospace SC Engineering GA 032CS UT WOS:000236752100015 ER PT J AU Meyer, WV Smart, AE Wegdam, GH Brown, RGW Dogariu, A AF Meyer, WV Smart, AE Wegdam, GH Brown, RGW Dogariu, A TI Photon correlation and scattering: introduction to the feature issue SO APPLIED OPTICS LA English DT Editorial Material AB This special issue of Applied Optics contains research papers on photon correlation and scattering, many of which were presented at the OSA Topical Meeting that was held 16-18 August 2004. (c) 2006 Optical Society of America. C1 NASA, Natl Ctr Space Explorat Res, Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Amsterdam, Waals Zeeman Inst, NL-1018 XE Amsterdam, Netherlands. Univ Nottingham, Nottingham NG7 2RD, England. CREOL, Sch Opt, Orlando, FL 32816 USA. RP Meyer, WV (reprint author), NASA, Natl Ctr Space Explorat Res, Glenn Res Ctr, 21000 Brookpk Rd,Mail Stop 110-3, Cleveland, OH 44135 USA. EM william.v.meyer@grc.nasa.gov NR 20 TC 1 Z9 1 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2006 VL 45 IS 10 BP 2149 EP 2154 DI 10.1364/AO.45.002149 PG 6 WC Optics SC Optics GA 029OE UT WOS:000236572000001 PM 16607978 ER PT J AU Vailati, A Cerbino, R Mazzoni, S Giglio, M Nikolaenko, G Takacs, CJ Cannell, DS Meyer, WV Smart, AE AF Vailati, A Cerbino, R Mazzoni, S Giglio, M Nikolaenko, G Takacs, CJ Cannell, DS Meyer, WV Smart, AE TI Gradient-driven fluctuations experiment: fluid fluctuations in microgravity SO APPLIED OPTICS LA English DT Article; Proceedings Paper CT Conference on Photon Correlation and Scattering CY AUG 16-18, 2004 CL Royal Netherlands Acad Sci, Amsterdam, NETHERLANDS HO Royal Netherlands Acad Sci ID RAYLEIGH-BENARD CONVECTION; NONEQUILIBRIUM FLUCTUATIONS; LIGHT-SCATTERING; LIQUID-MIXTURES; THERMAL-EQUILIBRIUM; DIFFUSION; GRAVITY AB We describe an experimental breadboard developed for the investigation of nonequilibrium fluctuations induced by macroscopic temperature and concentration gradients under microgravity conditions. Under these conditions the amplitude of the fluctuations diverges strongly for long wavelengths. The setup was developed at the University of Milan and at the University of California at Santa Barbara within the gradient-driven fluctuations experiment (GRADFLEX) project of the European Space Agency, in collaboration with the National Aeronautics and Space Administration. The apparatus uses a quantitative shadowgraph technique for characterization of the static power spectrum of the fluctuations S(q) and the measurement of their dynamics. We present preliminary experimental results for S(q) obtained in the presence of gravity for gradient-driven fluctuations for two cases, those induced in a liquid mixture with a concentration gradient produced by the Soret effect and those induced in a single-component fluid by a temperature gradient. (c) 2006 Optical Society of America. C1 INFM, CNR, I-20133 Milan, Italy. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Univ Calif Santa Barbara, Dept Phys & iQCD, Santa Barbara, CA 93106 USA. NASA, Natl Ctr Space Explorat Res, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Vailati, A (reprint author), INFM, CNR, Via Celoria 16, I-20133 Milan, Italy. EM vailati@fisica.unimi.it RI Vailati, Alberto/B-2299-2009; Mazzoni, Stefano/I-5865-2012; Cerbino, Roberto/A-2286-2008; OI Cerbino, Roberto/0000-0003-0434-7741; Vailati, Alberto/0000-0002-3119-6021 NR 33 TC 24 Z9 24 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2006 VL 45 IS 10 BP 2155 EP 2165 DI 10.1364/AO.45.002155 PG 11 WC Optics SC Optics GA 029OE UT WOS:000236572000002 PM 16607979 ER PT J AU Meyer, WV Mann, JA Wegdam, GH AF Meyer, WV Mann, JA Wegdam, GH TI Surface response functions for a thin-film between fluids with infinite boundaries and for a fluid-fluid interface between finite boundaries SO APPLIED OPTICS LA English DT Article; Proceedings Paper CT Conference on Photon Correlation and Scattering CY AUG 16-18, 2004 CL Royal Netherlands Acad Sci, Amsterdam, NETHERLANDS HO Royal Netherlands Acad Sci AB Measuring the surface response function of a fluid allows us to ascertain many of its properties. Simplified surface response functions are presented for several interface conditions, including (a) a thin-film between two fluids of infinite extent, (b) the newly derived fluid-fluid interface between finite boundaries, and (c) the traditional fluid-fluid interface between infinite boundaries. The finite-boundary derivation indicates that wall effects are very short range. This portends that the effects of external vibrations, which traditionally make this measurement challenging, can be mitigated by scattering from thin fluid layers. (c) 2006 Optical Society of America. C1 NASA, Natl Ctr Space Explorat Res, Glenn Res Ctr, Cleveland, OH 44135 USA. Case Western Reserve Univ, Dept Chem Engn, Cleveland, OH 44106 USA. Univ Amsterdam, Waals Zeeman Inst, NL-1018 XE Amsterdam, Netherlands. RP Meyer, WV (reprint author), NASA, Natl Ctr Space Explorat Res, Glenn Res Ctr, Mail Stop 110-3,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM william.v.meyer@grc.nasa.gov NR 5 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2006 VL 45 IS 10 BP 2174 EP 2185 DI 10.1364/AO.45.002174 PG 12 WC Optics SC Optics GA 029OE UT WOS:000236572000004 PM 16607981 ER PT J AU Leung, AB Suh, KI Ansari, RR AF Leung, AB Suh, KI Ansari, RR TI Particle-size and velocity measurements in flowing conditions using dynamic light scattering SO APPLIED OPTICS LA English DT Article; Proceedings Paper CT Conference on Photon Correlation and Scattering CY AUG 16-18, 2004 CL Royal Netherlands Acad Sci, Amsterdam, NETHERLANDS HO Royal Netherlands Acad Sci AB The noninvasive optical technique of dynamic light scattering (DLS) is routinely used to characterize dilute and transparent submicrometer particle dispersions in laboratory environments. A variety of industrial and biological applications would, however, greatly benefit from on-line monitoring of dispersions under flowing conditions. We present a model experiment to study flowing dispersions of polystyrene latex particles of varying sizes under varying flow conditions by using a newly developed fiber-optic DLS probe. A modified correlation function proposed in an earlier study is applied to the analysis of extracting the size and velocity of laminar flowing particulate dispersions. The complementary technique of laser Doppler velocimetry is also used to measure the speed of moving particles to confirm the DLS findings. (c) 2006 Optical Society of America. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM kwang.suh@grc.nasa.gov; rafat.r.ansari@nasa.gov NR 4 TC 18 Z9 20 U1 1 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2006 VL 45 IS 10 BP 2186 EP 2190 DI 10.1364/AO.45.002186 PG 5 WC Optics SC Optics GA 029OE UT WOS:000236572000005 PM 16607982 ER PT J AU Hoge, FE AF Hoge, FE TI Beam attenuation coefficient retrieval by inversion of airborne lidar-induced chromophoric dissolved organic matter fluorescence. 1. Theory SO APPLIED OPTICS LA English DT Article ID INHERENT OPTICAL-PROPERTIES; OCEAN COLOR MEASUREMENT; ABSORPTION-COEFFICIENT; VARIABILITY; SCATTERING; PACIFIC; FIELD; POC AB It is shown that the oceanic beam attenuation coefficient can be retrieved from airborne laser-induced and depth-resolved chromophoric dissolved organic matter (CDOM) fluorescence. The radiative transfer equation (RTE) retrieval methodology does not require a laser beam spread function model since two CDOM fluorescence bands are used in conjunction with a beam attenuation spectral model, is self-normalizing since the CDOM absorption coefficient and laser beam irradiance are common to both fluorescence observational channels, and is enabled by the known isotropic phase function for CDOM fluorescence. Although this RTE analytical inversion theory is exact, the retrieval uncertainty is reduced by configuring the proposed lidar in the multiple-field-of-view beam attenuation mode to significantly diminish observation of multiple scattering. The theory can be applied over wide regions of the ocean's continental margins, estuaries, lakes, and rivers that are known to have sufficient CDOM. (c) 2006 Optical Society of America. C1 NASA, Goddard Space Flight Ctr, Wallops Isl, VA 23337 USA. RP Hoge, FE (reprint author), NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Wallops Isl, VA 23337 USA. EM frank.hoge@nasa.gov NR 33 TC 0 Z9 1 U1 0 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2006 VL 45 IS 10 BP 2344 EP 2351 DI 10.1364/AO.45.002344 PG 8 WC Optics SC Optics GA 029OE UT WOS:000236572000027 PM 16608003 ER PT J AU Czaja, AD Kudryavtsev, AB Schopf, JW AF Czaja, AD Kudryavtsev, AB Schopf, JW TI New method for the microscopic, nondestructive acquisition of ultraviolet resonance Raman spectra from plant cell walls SO APPLIED SPECTROSCOPY LA English DT Article DE ultraviolet resonance Raman spectroscopy; UVRR; plant cell walls; xylem; lignin ID FOURIER-TRANSFORM RAMAN; PULSED LASER EXCITATION; PINUS-SYLVESTRIS WOOD; SINGLE LIVING CELLS; FT-RAMAN; EXTRACTABLE COMPOUNDS; RAPID DETECTION; PICEA-MARIANA; SPECTROSCOPY; LIGNIN AB Raman spectroscopy has long been used for the chemical analysis of organic matter, including natural products, using excitation wavelengths in the visible, infrared, or ultraviolet portions of the spectrum. The use of ultraviolet resonance Raman spectroscopy (UVRR) to study bulk samples of plant tissue has typically been carried out by rotating homogeneous macro-samples beneath the laser beam in order to minimize the amount of UV radiation impinging on any one spot, thereby avoiding its potentially damaging effects on the organic matter analyzed. This paper extends the use of UVRR to the study on a microscopic scale of individual plant cell walls by use of the controlled micro-displacement of a sample. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Ctr Study Evolut & Origin Life, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Ctr Astrobiol, NASA, Astrobiol Inst, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Mol Biol, Los Angeles, CA 90095 USA. RP Czaja, AD (reprint author), Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. EM aczaja@ess.ucla.edu NR 36 TC 3 Z9 3 U1 4 U2 12 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD APR PY 2006 VL 60 IS 4 BP 352 EP 355 DI 10.1366/000370206776593753 PG 4 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 033ED UT WOS:000236828500002 PM 16613629 ER PT J AU Schulte, M Blake, D Hoehler, T Mccollom, T AF Schulte, Mitch Blake, David Hoehler, Tori McCollom, Thomas TI Serpentinization and its implications for life on the early Earth and Mars SO ASTROBIOLOGY LA English DT Article DE serpentinization; ophiolite; habitability; early Earth; Mars ID MID-ATLANTIC RIDGE; HYDROTHERMAL SYSTEMS; ENERGY-REQUIREMENTS; OCEANIC-CRUST; LOST CITY; SUBSURFACE; FLUIDS; MAINTENANCE; CALIFORNIA; OPHIOLITE AB Ophiolites, sections of ocean crust tectonically displaced onto land, offer significant potential to support chemolithoautotrophic life through the provision of energy and reducing power during aqueous alteration of their highly reduced mineralogies. There is substantial chemical disequilibrium between the primary olivine and pyroxene mineralogy of these ophiolites and the fluids circulating through them. This disequilibrium represents a potential source of chemical energy that could sustain life. Moreover, Eh-pH conditions resulting from rock-water interactions in ultrabasic rocks are conducive to important abiotic processes antecedent to the origin of life. Serpentinization-the reaction of olivine- and pyroxene-rich rocks with water-produces magnetite, hydroxide, and serpentine minerals, and liberates molecular hydrogen, a source of energy and electrons that can be readily utilized by a broad array of chemosynthetic organisms. These systems are viewed as important analogs for potential early ecosystems on both Earth and Mars, where highly reducing mineralogy was likely widespread in an undifferentiated crust. Secondary phases precipitated during serpentinization have the capability to preserve organic or mineral biosignatures. We describe the petrology and mineral chemistry of an ophiolite-hosted cold spring in northern California and propose criteria to aid in the identification of serpentinizing terranes on Mars that have the potential to harbor chemosynthetic life. C1 Univ Missouri, Dept Geol Sci, Columbia, MO 65203 USA. NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. RP Schulte, M (reprint author), Univ Missouri, Dept Geol Sci, 101 Geol Bldg, Columbia, MO 65203 USA. EM schultemd@missouri.edu NR 63 TC 99 Z9 99 U1 6 U2 60 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD APR PY 2006 VL 6 IS 2 BP 364 EP 376 DI 10.1089/ast.2006.6.364 PG 13 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 043CM UT WOS:000237576900007 PM 16689652 ER PT J AU Onstott, TC McGown, D Kessler, J Lollar, BS Lehmann, KK Clifford, SM AF Onstott, TC McGown, D Kessler, J Lollar, BS Lehmann, KK Clifford, SM TI Martian CH4: Sources, flux, and detection SO ASTROBIOLOGY LA English DT Article DE Mars; methane; methanogens; Fischer-Tropsch reactions; infrared spectroscopy ID RING-DOWN SPECTROSCOPY; WITWATERSRAND BASIN; SOUTH-AFRICA; ISOTOPIC FRACTIONATION; ZAMBALES OPHIOLITE; RADIOGENIC GASES; NOBLE-GASES; METHANE; MARS; DEEP AB Recent observations have detected trace amounts of CH4 heterogeneously distributed in the martian atmosphere, which indicated a subsurface CH4 flux of similar to 2 x 10(5) to 2 X 10(9) cm(-2) s(-1). Four different origins for this CH4 were considered: (1) volcanogenic; (2) sublimation of hydrate-rich ice; (3) diffusive transport through hydrate-saturated cryosphere; and (4) microbial CH4 generation above the cryosphere. A diffusive flux model of the martian crust for He, H-2, and CH4 was developed based upon measurements of deep fracture water samples from South Africa. This model distinguishes between abiogenic and microbial CH4 sources based upon their isotopic composition, and couples microbial CH4 production to H-2 generation by H2O radiolysis. For a He flux of -10(5) cm(-2) s(-1) this model yields an abiogenic CH4 flux and a microbial CH4 flux of similar to 10(6) and similar to 10(9) cm(-2) s(-1), respectively. This flux will only reach the martian surface if CH4 hydrate is saturated in the cryosphere; otherwise it will be captured within the cryosphere. The sublimation of a hydrate-rich cryosphere could generate the observed CH4 flux, whereas microbial CH4 production in a hypersaline environment above the hydrate stability zone only seems capable of supplying -105 cm(-2) s(-1) of CH4. The model predicts that He/H-2/CH4/C2H6 abundances and the C and H isotopic values of CH4 and the C isotopic composition of C2H6 could reveal the different sources. Cavity ring-down spectrometers represent the instrument type that would be most capable of performing the C and H measurements of CH4 on near future rover missions and pinpointing the cause and source of the CH4 emissions. C1 Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Indiana Univ, NASA, Astrobiol Inst, IPTAI, Bloomington, IN USA. Univ Toronto, Dept Geol, Toronto, ON, Canada. Lunar Planetary Inst, Houston, TX USA. RP Onstott, TC (reprint author), Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. EM tullis@princeton.edu NR 76 TC 41 Z9 43 U1 3 U2 19 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD APR PY 2006 VL 6 IS 2 BP 377 EP 395 DI 10.1089/ast.2006.6.377 PG 19 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 043CM UT WOS:000237576900008 PM 16689653 ER PT J AU Romano, P Moretti, A Banat, PL Burrows, DN Campana, S Chincarini, G Covino, S Malesani, D Tagliaferri, G Kobayashi, S Zhang, B Falcone, AD Angelini, L Barthelmy, S Beardmore, AP Capalbi, M Cusumano, G Giommi, P Goad, MR Godet, O Grupe, D Hill, JE Kennea, JA La Parola, V Mangano, V Meszaros, P Morris, DC Nousek, JA O'Brien, PT Osborne, JP Parsons, A Perri, M Pagani, C Page, KL Wells, AA Gehrels, N AF Romano, P Moretti, A Banat, PL Burrows, DN Campana, S Chincarini, G Covino, S Malesani, D Tagliaferri, G Kobayashi, S Zhang, B Falcone, AD Angelini, L Barthelmy, S Beardmore, AP Capalbi, M Cusumano, G Giommi, P Goad, MR Godet, O Grupe, D Hill, JE Kennea, JA La Parola, V Mangano, V Meszaros, P Morris, DC Nousek, JA O'Brien, PT Osborne, JP Parsons, A Perri, M Pagani, C Page, KL Wells, AA Gehrels, N TI X-ray flare in XRF 050406: evidence for prolonged engine activity SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : bursts; X-rays : bursts; X-rays : individuals : XRF 050406 ID BURST AFTERGLOWS; SWIFT OBSERVATIONS; BATSE OBSERVATIONS; PEAK ENERGY; TELESCOPE; BRIGHT; LONG; EMISSION; SPECTRA; MISSION AB We present observations of XRF 050406, the first burst detected by Swift showing a flare in its X-ray light curve. During this flare, which peaks at t(peak) similar to 210s after the BAT trigger, a flux variation of delta F/F similar to 6 in a very short time delta t/t(peak) << 1 was observed. Its measured fluence in the 0.2-10 keV band was similar to 1.4 x 10(-8) erg cm(-2), which corresponds to 1-15% of the prompt fluence. We present indications of spectral variations during the flare. We argue that the producing mechanism is late internal shocks, which implies that the central engine is still active at 210 s, though with a reduced power with respect to the prompt emission. The X-ray light curve flattens to a very shallow slope with decay index of similar to 0.5 after similar to 4400 s, which also supports continued central engine activity at late times. This burst is classified as an X-ray flash, with a relatively low fluence (similar to 10(-7) erg cm(-2) in the 15-350 keV band, E(iso) similar to 10(51) erg), a soft spectrum (photon index 2.65), no significant flux above similar to 50 keV and a peak energy E(p) < 15 keV. XRF 050406 is one of the first examples of a well-studied X-ray light curve of an XRF. We show that the main afterglow characteristics are qualitatively similar to those of normal GRBs. In particular, X-ray flares superimposed on a power-law light curve have now been seen in both XRFs and GRBs. This indicates that a similar mechanism may be at work for both kinds of events. C1 Osserv Astron Brera, INAF, I-23807 Merate, LC, Italy. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. SISSA, ISAS, I-34014 Trieste, Italy. Penn State Univ, Ctr Gravitat Wave Phys, Davey Lab 104, University Pk, PA 16802 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Leicester, Dept Phys & Astron, Xray & Observ Astron Grp, Leicester LE1 7RH, Leics, England. ASI Sci Data Ctr, I-00044 Frascati, Italy. INAF, Ist Astrofis Spaziale & Fis Cosmica, Sez Palermo, I-90146 Palermo, Italy. Agenzia Spaziale Italiana, Unita Osservaz Universo, I-00198 Rome, Italy. Univ Space Res Assoc, Columbia, MD 21044 USA. RP Romano, P (reprint author), Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy. EM romano@merate.mi.astro.it RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; Parsons, Ann/I-6604-2012; OI giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488; Covino, Stefano/0000-0001-9078-5507; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 72 TC 78 Z9 80 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 450 IS 1 BP 59 EP 68 DI 10.1051/0004-6361:20054172 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 029JO UT WOS:000236558700012 ER PT J AU Burgarella, D Perez-Gonzalez, PG Tyler, KD Rieke, GH Buat, V Takeuchi, TT Lauger, S Arnouts, S Ilbert, O Barlow, TA Bianchi, L Lee, YW Madore, BF Malina, RF Szalay, AS Yi, SK AF Burgarella, D Perez-Gonzalez, PG Tyler, KD Rieke, GH Buat, V Takeuchi, TT Lauger, S Arnouts, S Ilbert, O Barlow, TA Bianchi, L Lee, YW Madore, BF Malina, RF Szalay, AS Yi, SK TI Ultraviolet-to-far infrared properties of Lyman break galaxies and luminous infrared galaxies at z similar to 1 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE cosmology : observations; galaxies : starburst; ultraviolet : galaxies; infrared : galaxies; galaxies : evolution; galaxies : fundamental parameters ID STAR-FORMATION RATE; HUBBLE-DEEP-FIELD; HIGH-REDSHIFT; STARBURST GALAXIES; DUST ATTENUATION; FORMING GALAXIES; EVOLUTION; SOUTH; MORPHOLOGY; DENSITY AB Aims. We present the first large, unbiased sample of Lyman Break Galaxies (LBGs) at z similar to 1. Far ultraviolet-dropout (1530 angstrom) galaxies in the Chandra Deep Field South have been selected using GALEX data. This first large sample in the z similar to 1 universe provides us with a high quality reference sample of LBGs. Methods. We analyzed the sample from the UV to the IR using GALEX, SPITZER, ESO and HST data. Results. The morphology (obtained from GOODS data) of 75% of our LBGs is consistent with a disk. The vast majority of LBGs with an IR detection are also Luminous Infrared Galaxies (LIRGs). As a class, the galaxies not detected at 24 mu m are an order of magnitude fainter relative to the UV compared with those detected individually, suggesting that there may be two types of behavior within the sample. For the IR-bright galaxies, there is an apparent upper limit for the UV dust attenuation and this upper limit is anti-correlated with the observed UV luminosity. Previous estimates of dust attenuations based on the ultraviolet slope are compared to new ones based on the FIR/UV ratio (for LBGs detected at 24 mu m), which is usually a more reliable estimator. Depending on the calibration we use to estimate the total IR luminosity, beta-based attenuations A(FUV) are larger by 0.2 to 0.6 mag. than the ones estimated from FIR/UV ratio. Finally, for IR-bright LBGs, median estimated beta-based SFRs are 2-3 times larger than the total SFRs estimated as SFRTOT = SFRUV + SFRIR while IR-based SFRs provide values below SFRTOT by 15-20%. We use a stacking method to statistically constrain the 24 mu m flux of LBGs non individually detected. The results suggest that these LBGs do not contain large amounts of dust. C1 Observ Astron Marseille Prov, Lab Astrophys Marseille, F-13376 Marseille 12, France. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Osservatorio Astron Bologna, Bologna, Italy. CALTECH, Pasadena, CA 91125 USA. Johns Hopkins Univ, Ctr Astrophys Sci, Baltimore, MD 21218 USA. Yonsei Univ, Ctr Space Astrophys, Seoul 120749, South Korea. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. CALTECH, NASA, IPAC Extragalact Database, Pasadena, CA 91125 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Burgarella, D (reprint author), Observ Astron Marseille Prov, Lab Astrophys Marseille, F-13376 Marseille 12, France. EM denis.burgarella@oamp.fr; pgperez@as.arizona.edu; ktyler@as.arizona.edu; grieke@as.arizona.edu; veronique.buat@oamp.fr; tsutomu.takeuchi@oamp.fr; sebastien.lauger@oamp.fr; olivier.ilbert1@bo.astro.it; tab@srl.caltech.edu; bianchi@skyrv.pha.jhu.edu; ywlee@galaxy.yonsei.ac.kr; barry@ipac.caltech.edu; szalay@tardis.pha.jhu.edu; yi@galaxy.yonsei.ac.kr RI Perez-Gonzalez, Pablo/J-2871-2016; OI Perez-Gonzalez, Pablo/0000-0003-4528-5639; malina, roger/0000-0003-3399-3865 NR 46 TC 45 Z9 45 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 450 IS 1 BP 69 EP 76 DI 10.1051/0004-6361:20054309 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 029JO UT WOS:000236558700013 ER PT J AU Lundqvist, M Nilsson, H Wahlgren, GM Lundberg, H Xu, HL Jang, ZK Leckrone, DS AF Lundqvist, M Nilsson, H Wahlgren, GM Lundberg, H Xu, HL Jang, ZK Leckrone, DS TI Improved oscillator strengths and wavelengths in HfII, with applications to stellar elemental abundances SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE atomic data; line : identification; stars : abundances ID STAR CHI-LUPI; CHEMICALLY PECULIAR STAR; R-PROCESS; METAL-POOR; RICH; LIFETIMES AB Aims. We present new and improved radiative lifetimes for eight levels in HfI and 18 levels in HfII, along with oscillator strengths and wavelengths for 195 transitions in HfII. With these data we determine the abundance of hafnium in two chemically peculiar stars: the hot-Am star HR 3383 and the HgMn star chi Lupi, and discuss the implications of the new data to the hafnium abundance for the Sun and the metal-poor galactic halo stars CS 22892-052 and CS 31082-001. Methods. The oscillator strengths are derived by combining radiative lifetimes measured with the laser induced fluorescence technique and branching fractions determined from intensity calibrated Fourier transform spectra. The hafnium abundance in the two sharp-lined peculair stars is determined by comparison of spectra obtained from instruments onboard the Hubble Space Telescope with synthetic spectra, while the abundance of hafnium in the solar photosphere and the metal-poor halo stars is discussed in terms of rescaling previous investigations using the new g f values. Results. The abundance enhancement of hafnium has been determined in HR 3383 to be +1.7 dex and that for chi Lupi A is +1.3 dex. In the course of the analysis we have also determined an abundance enhancement for molybdenum in HR 3383 to be +1.2 dex, which is similar to that known for. Lupi A. The abundances in the metal-poor halo stars CS 31082-001 and CS 22892-052 were rescaled to log epsilon(Hf) = -0.75 and -0.82 respectively, with smaller 1 sigma uncertainty. This has the effect of improving the theoretical fits of r-process nucleosynthesis to abundance data for heavy elements. The change of g f values also implies that the hafnium abundance in the solar photosphere should be reduced by up to 0.2 dex, thereby inducing a discrepancy with the meteoritic hafnium abundance. C1 Lund Univ, Lund Observ, S-22100 Lund, Sweden. Lund Inst Technol, Dept Phys, S-22100 Lund, Sweden. Jilin Univ, Dept Phys, Changchun 130023, Peoples R China. Univ Laval, Dept Phys Engn & Opt, Ste Foy, PQ G1K 7P4, Canada. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. RP Lundqvist, M (reprint author), Lund Univ, Lund Observ, Box 43, S-22100 Lund, Sweden. EM martin.lundqvist@astro.lu.se RI Xu, Huailiang/A-6011-2008 NR 27 TC 12 Z9 12 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 450 IS 1 BP 407 EP U115 DI 10.1051/0004-6361:20054474 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 029JO UT WOS:000236558700046 ER PT J AU Campana, S Romano, P Covino, S Lazzati, D De Luca, A Chincarini, G Moretti, A Tagliaferri, G Cusumano, G Giommi, P Mangano, V Perri, M La Parola, V Capalbi, M Mineo, T Antonelli, LA Burrows, DN Hill, JE Racusin, JL Kennea, JA Morris, DC Pagani, C Nousek, JA Osborne, JP Goad, MR Page, KL Beardmore, AP Godet, O O'Brien, PT Wells, AA Angelini, L Gehrels, N AF Campana, S Romano, P Covino, S Lazzati, D De Luca, A Chincarini, G Moretti, A Tagliaferri, G Cusumano, G Giommi, P Mangano, V Perri, M La Parola, V Capalbi, M Mineo, T Antonelli, LA Burrows, DN Hill, JE Racusin, JL Kennea, JA Morris, DC Pagani, C Nousek, JA Osborne, JP Goad, MR Page, KL Beardmore, AP Godet, O O'Brien, PT Wells, AA Angelini, L Gehrels, N TI Evidence for intrinsic absorption in the Swift X-ray afterglows SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : bursts; X-rays : general ID PHOTOELECTRIC ABSORPTION; ALPHA SYSTEMS; HOST GALAXY; BURSTS; EMISSION; TELESCOPE; DUST; PHOTOIONIZATION; INTERSTELLAR; SPECTROSCOPY AB Gamma-ray burst (GRB) progenitors are observationally linked to the death of massive stars. X-ray studies of the GRB afterglows can deepen our knowledge of the ionization status and metal abundances of the matter in the GRB environment. Moreover, the presence of local matter can be inferred through its fingerprints in the X-ray spectrum, i.e. the presence of absorption higher than the Galactic value. A few studies based on BeppoSAX and XMM-Newton found evidence of higher than Galactic values for the column density in a number of GRB afterglows. Here we report on a systematic analysis of 17 GRBs observed by Swift up to April 15, 2005. We observed a large number of GRBs with an excess of column density. Our sample, together with previous determinations of the intrinsic column densities for GRBs with known redshift, provides evidence for a distribution of absorption consistent with that predicted for randomly occurring GRB within molecular clouds. C1 Osserv Astron Brera, INAF, I-23807 Merate, LC, Italy. Univ Colorado, JILA, Boulder, CO 80309 USA. Ist Astrofis Spaziale & Fis Cosmica, INAF, I-20133 Milan, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. Ist Astrofis Spaziale & Fis Cosmica, INAF, I-90146 Palermo, Italy. Agenzia Spaziale Italiana, Sci Data Ctr, I-00044 Frascati, Italy. Osserv Astron Roma, INAF, I-00040 Rome, Italy. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ Leicester, Space Res Ctr, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Campana, S (reprint author), Osserv Astron Brera, INAF, Via Bianchi 46, I-23807 Merate, LC, Italy. EM campana@merate.mi.astro.it RI Gehrels, Neil/D-2971-2012; Racusin, Judith/D-2935-2012; OI Mineo, Teresa/0000-0002-4931-8445; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488; De Luca, Andrea/0000-0001-6739-687X; Covino, Stefano/0000-0001-9078-5507; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 49 TC 39 Z9 39 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 1 BP 61 EP 65 DI 10.1051/0004-6361:20053823 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 021OD UT WOS:000235991600009 ER PT J AU Goad, MR Tagliaferri, G Page, KL Moretti, A Osborne, JP Kobayashi, S Kumar, P Meszaros, PI Chincarini, G Sakamoto, T Zhang, B Barthelmy, SD Beardmore, AP Burrows, DN Campana, S Capalbi, M Cominsky, L Cusumano, G Gehrels, N Giommi, P Godet, O Hill, JE Kennea, JA Krimm, H La Parola, V Mangano, V Mineo, T Morris, DC Mukerjee, K Nousek, JA O'Brien, PT Pagani, C Perri, M Romano, P Wells, AA AF Goad, MR Tagliaferri, G Page, KL Moretti, A Osborne, JP Kobayashi, S Kumar, P Meszaros, PI Chincarini, G Sakamoto, T Zhang, B Barthelmy, SD Beardmore, AP Burrows, DN Campana, S Capalbi, M Cominsky, L Cusumano, G Gehrels, N Giommi, P Godet, O Hill, JE Kennea, JA Krimm, H La Parola, V Mangano, V Mineo, T Morris, DC Mukerjee, K Nousek, JA O'Brien, PT Pagani, C Perri, M Romano, P Wells, AA TI Swift observations of the prompt X-ray emission and afterglow from GRB050126 and GRB050219A SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : bursts; gamma rays : observations; black hole physics ID GAMMA-RAY; BURST SPECTRA; BATSE OBSERVATIONS; PEAK ENERGY; SHOCK MODEL; GRB 990123; TELESCOPE; FLASHES; PHOTOSPHERES; ENERGETICS AB We report on the temporal and spectral characteristics of the early X-ray emission from the Gamma Ray Bursts GRB050126 and GRB050219A as observed by Swift. The X-ray light-curves of these 2 bursts both show remarkably steep early decays (F(t) proportional to t(-3)), breaking to flatter slopes on timescales of a few hundred seconds. For GRB050126 the burst shows no evidence of spectral evolution in the 20-150 keV band, and the spectral index of the gamma-ray and X-ray afterglows are significantly different suggesting a separate origin. By contrast the BAT spectrum of GRB050219A displays significant spectral evolution, becoming softer at later times, with G evolving toward the XRT photon index seen in the early X-ray afterglow phase. For both bursts, the 0.2-10 keV spectral index pre- and post-break in the X-ray decay light-curve are consistent with no spectral evolution. We suggest that the steep early decline in the X-ray decay light-curve is either the curvature tail of the prompt emission; X-ray flaring activity; or external forward shock emission from a jet with high density regions of small angular size (>Gamma(-1)). The late slope we associate with the forward external shock. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Osserv Astron Brera, INAF, I-23807 Merate, Italy. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. Univ Milano Bicocca, I-20126 Milan, Italy. ASI Sci Data Ctr, I-00044 Frascati, Italy. Inst Astrofis Spaziale & Cosmica, INAF, I-90146 Palermo, Italy. Univ Space Res Assoc, Columbia, MD 21044 USA. RP Goad, MR (reprint author), Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. EM mrg@star.le.ac.uk RI Gehrels, Neil/D-2971-2012; Barthelmy, Scott/D-2943-2012; OI Mineo, Teresa/0000-0002-4931-8445; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 46 TC 17 Z9 17 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 1 BP 89 EP 100 DI 10.1051/0004-6361:20054457 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 021OD UT WOS:000235991600012 ER PT J AU Tripathi, D Solanki, SK Schwenn, R Bothmer, V Mierla, M Stenborg, G AF Tripathi, D Solanki, SK Schwenn, R Bothmer, V Mierla, M Stenborg, G TI Observation of a bright coronal downflow by SOHO/EIT SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : corona; Sun : coronal mass ejections (CMEs); Sun : prominences; Sun : filaments ID FLARE SUPRA-ARCADE; SOLAR-FLARE; MASS EJECTIONS; INFLOWS; SUMER; RECONNECTION; TELESCOPE; MISSION; HOT AB A distinct coronal downflow has been discovered in the course of a prominence eruption associated coronal mass ejection (CME) imaged by EIT ( Extreme ultraviolet Imaging Telescope) and LASCO ( Large Angle Spectrometric Coronagraph) on board SOHO ( Solar and Heliospheric Observatory) on 5-Mar.-2000. Evolution of the prominences seen by EIT was tracked into the LASCO/ C2 and C3 field-of-view where they developed as the core of a typical three-part CME. In contrast to the inflow structures reported earlier in the literatures, which were dark and were interpreted as plasma voids moving down, the downflow reported here was bright. The downflow, which was only seen in EIT FOV had an onset time that coincided with the deceleration phase of the core of the CME. The downflow showed a rapid acceleration followed by a strong deceleration. The downflow followed a curved path which may be explained by material following the apex of a contracting magnetic loop sliding down along other field lines, although other explanations are also possible. Irrespective of the detailed geometry, this observation provides support for the pinching off of the field lines drawn-out by the erupting prominences and the contraction of the arcade formed by the reconnection. C1 Max Planck Inst Sonnensyst Forsch, D-37191 Katlenburg Lindau, Germany. Univ Gottingen, Inst Astrophys, D-3400 Gottingen, Germany. Catholic Univ Amer, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Tripathi, D (reprint author), Univ Cambridge, Ctr Math Sci, Dept Appl Math & Theoret Phys, Wilberforce Rd, Cambridge CB3 0WA, England. EM d.tripathi@damtp.cam.ac.uk; solanki@mps.mpg.de; schwenn@mps.mpg.de; bothmer@astro.physik.uni-goettingen.de; mierla@mps.mpg.de; stenborg@kreutz.nascom.nasa.gov RI Tripathi, Durgesh/D-9390-2012; Solanki, Sami/E-2487-2013 OI Tripathi, Durgesh/0000-0003-1689-6254; Solanki, Sami/0000-0002-3418-8449 NR 25 TC 23 Z9 23 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 1 BP 369 EP 378 DI 10.1051/0004-6361:20053840 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 021OD UT WOS:000235991600037 ER PT J AU Thompson, WT AF Thompson, WT TI Coordinate systems for solar image data SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE standards; Sun : general; techniques : image processing; astronomical data bases : miscellaneous; methods : data analysis ID MISSION; FITS AB A set of formal systems for describing the coordinates of solar image data is proposed. These systems build on current practice in applying coordinates to solar image data. Both heliographic and heliocentric coordinates are discussed. A distinction is also drawn between heliocentric and helioprojective coordinates, where the latter takes the observer's exact geometry into account. The extension of these coordinate systems to observations made from non-terrestial viewpoints is discussed, such as from the upcoming STEREO mission. A formal system for incorporation of these coordinates into FITS files, based on the FITS World Coordinate System, is described, together with examples. C1 NASA, Goddard Space Flight Ctr, Commun GSI L3, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Commun GSI L3, Code 612-1, Greenbelt, MD 20771 USA. EM William.T.Thompson.1@gsfc.nasa.gov RI Thompson, William/D-7376-2012 NR 16 TC 90 Z9 91 U1 0 U2 4 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 2 BP 791 EP 803 DI 10.1051/0004-6361:20054262 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 024MH UT WOS:000236198600042 ER PT J AU Wijnands, R in't Zand, JJM Rupen, M Maccarone, T Homan, J Cornelisse, R Fender, R Grindlay, J van der Klis, M Kuulkers, E Markwardt, CB Miller-Jones, JCA Wang, QD AF Wijnands, R in't Zand, JJM Rupen, M Maccarone, T Homan, J Cornelisse, R Fender, R Grindlay, J van der Klis, M Kuulkers, E Markwardt, CB Miller-Jones, JCA Wang, QD TI The XMM-Newton/Chandra monitoring campaign of the Galactic center region - Description of the program and preliminary results SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE accretion, accretion disks; binaries : close; X-rays : binaries ID X-RAY TRANSIENT; SOURCE 1E 1743.1-2843; NEUTRON-STAR; DISCOVERY; EMISSION; BINARIES; BURSTERS; CATALOG; OSCILLATIONS; BEPPOSAX AB We present the first results of our X-ray monitoring campaign on a 1.7 square degree region centered on Sgr A* using the satellites XMM-Newton and Chandra. The purpose of this campaign is to monitor the behavior (below 10 keV) of X-ray sources (both persistent and transient) which are too faint to be detected by monitoring instruments aboard other satellites currently in orbit (e.g., Rossi X-ray Timing Explorer; INTEGRAL). Our first monitoring observations (using the HRC-I aboard Chandra) were obtained on June 5, 2005. Most of the sources detected could be identified with foreground sources, such as X-ray active stars. In addition we detected two persistent X-ray binaries (1E 1743.1-2843; 1A 1742-294), two faint X-ray transients (GRS 1741.9-2853; XMM J174457-2850.3), as well as a possible new transient source at a luminosity of a few times 10(34) erg s(-1). We report on the X-ray results on these systems and on the non-detection of the transients in follow-up radio data using the Very Large Array. We discuss how our monitoring campaign can help to improve our understanding of the different types of X-ray transients (i.e., the very faint ones). C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. SRON Netherlands Inst Space Res, NL-3584 CA Utrecht, Netherlands. Natl Radio Astron Observ, Socorro, NM 87801 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20711 USA. Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. ESA, ESTEC, ISOC, Madrid 28080, Spain. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. RP Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM rudy@science.uva.nl; jeanz@sron.nl; mrupen@milkyway.gsfc.nasa.gov; tjm@astro.soton.ac.uk; jeroen@space.mit.edu; cornelis@astro.soton.ac.uk; rpf@phys.soton.ac.uk; josh@cfa.harvard.edu; michiel@science.va.nl; Erik.Kuulkers@esa.int; craigm@milkyway.gsfc.nasa.gov; jmiller@science.uva.nl; wqd@astro.umass.edu RI Miller-Jones, James/B-2411-2013 OI Miller-Jones, James/0000-0003-3124-2814 NR 59 TC 71 Z9 71 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 3 BP 1117 EP U199 DI 10.1051/0004-6361:20054129 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 025ET UT WOS:000236248800024 ER PT J AU Poutanen, T de Gasperis, G Hivon, E Kurki-Suonio, H Balbi, A Borrill, J Cantalupo, C Dore, O Keihanen, E Lawrence, CR Maino, D Natoli, P Prunet, S Stompor, R Teyssier, R AF Poutanen, T de Gasperis, G Hivon, E Kurki-Suonio, H Balbi, A Borrill, J Cantalupo, C Dore, O Keihanen, E Lawrence, CR Maino, D Natoli, P Prunet, S Stompor, R Teyssier, R TI Comparison of map-making algorithms for CMB experiments SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE methods : data analysis; cosmology : cosmic microwave background ID MICROWAVE BACKGROUND ANISOTROPIES; POWER SPECTRUM ESTIMATION; SCANNING STRATEGY; PLANCK SURVEYOR; DESTRIPING TECHNIQUE; LOSING INFORMATION; POLARIZED DATA; 1/F NOISE; DATA SETS; MISSION AB We have compared the cosmic microwave background (CMB) temperature anisotropy maps made from one-year time ordered data (TOD) streams that simulated observations of the originally planned 100 GHz Planck Low Frequency Instrument (LFI). The maps were made with three different codes. Two of these, ROMA and MapCUMBA, were implementations of maximum-likelihood (ML) map-making, whereas the third was an implementation of the destriping algorithm. The purpose of this paper is to compare these two methods, ML and destriping, in terms of the maps they produce and the angular power spectrum estimates derived from these maps. The difference in the maps produced by the two ML codes was found to be negligible. As expected, ML was found to produce maps with lower residual noise than destriping. In addition to residual noise, the maps also contain an error which is due to the effect of subpixel structure in the signal on the map-making method. This error is larger for ML than for destriping. If this error is not corrected a bias will be introduced in the power spectrum estimates. This study is related to Planck activities. C1 Helsinki Inst Phys, Helsinki 00014, Finland. Univ Helsinki, Dept Phys Sci, FIN-00014 Helsinki, Finland. Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy. CALTECH, IPAC, Pasadena, CA 91125 USA. Ist Nazl Fis Nucl, Sez Roma 2, I-00133 Rome, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08540 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Milan, Dipartimento Fis, I-20131 Milan, Italy. Inst Astrophys Paris, F-75104 Paris, France. Ctr Etud Saclay, Serv Astrophys, DAPNIA, F-91191 Gif Sur Yvette, France. RP Poutanen, T (reprint author), Helsinki Inst Phys, POB 64, Helsinki 00014, Finland. EM torsti.poutanen@helsinki.fi RI de Gasperis, Giancarlo/C-8534-2012; Kurki-Suonio, Hannu/B-8502-2016; OI de Gasperis, Giancarlo/0000-0003-2899-2171; Kurki-Suonio, Hannu/0000-0002-4618-3063; Hivon, Eric/0000-0003-1880-2733 NR 35 TC 27 Z9 27 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 3 BP 1311 EP U274 DI 10.1051/0004-6361:20052845 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 025ET UT WOS:000236248800042 ER PT J AU Pian, EP Foschini, LF Beckmann, VB Soldi, SS Turler, MT Gehrels, N Ghisellini, GG Giommi, P Maraschi, LM Pursimo, TP Raiteri, CM Tagliaferri, G Tornikoski, M Tosti, G Treves, A Villata, M Barr, P Courvoisier, TJL Di Cocco, G Hudec, R Fuhrmann, L Malaguti, G Persic, M Tavecchio, F Walter, R AF Pian, EP Foschini, LF Beckmann, VB Soldi, SS Turler, MT Gehrels, N Ghisellini, GG Giommi, P Maraschi, LM Pursimo, TP Raiteri, CM Tagliaferri, G Tornikoski, M Tosti, G Treves, A Villata, M Barr, P Courvoisier, TJL Di Cocco, G Hudec, R Fuhrmann, L Malaguti, G Persic, M Tavecchio, F Walter, R TI INTEGRAL observations of the blazar 3C 454.3 in outburst SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : active; X-rays : observations ID ACTIVE GALACTIC NUCLEI; X-RAY-SPECTRA; RADIO-SOURCES; UNIFIED SCHEMES; JEM-X; BLAZARS; EMISSION; QUASARS; PHOTOMETRY; SOFTWARE AB In Spring 2005, the blazar 3C 454.3 underwent a dramatic outburst at all wavelengths from mm to X-rays. This prompted INTEGRAL observations, accomplished in 15 servations, 15-18 May 2005. The source was detected by the INTEGRAL instruments from 3 to 200 keV in a bright state (similar to 5 x 10(-10) erg s(-1) cm(-2)), at least a factor of 2-3 higher than previously observed. This is one of the brightest blazar detections achieved by INTEGRAL. During the 2.5 days of. INTEGRAL monitoring, we detected a similar to 20% decrease in the hard X-rays (20-40 keV), indicating that we have sampled the decaying part of the flare. The decrease is less apparent in the soft X-rays (5-15 keV). The simultaneous optical variations are weakly correlated with those at soft X-rays, and not clearly correlated with those at hard X-rays. The spectral energy distribution exhibits two components, as typically seen in blazars, which can be modeled with synchrotron radiation and inverse Compton scattering occurring in a region external to the broad line region. C1 Osserv Astron Trieste, INAF, I-34131 Trieste, Italy. IASF Bologna, INAF, I-40129 Bologna, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, Baltimore, MD 21250 USA. INTEGRAL Sci Data Ctr, CH-1290 Versoix, Switzerland. Observ Geneva, CH-1290 Sauverny, Switzerland. Osserv Astron Brera, INAF, I-23807 Merate, LC, Italy. ASI Sci Data Ctr, I-00044 Frascati, Italy. Osserv Astron Brera, INAF, I-20121 Milan, Italy. Nord Opt Telescope, Santa Cruz De La Palma 38700, Spain. Osserv Astron Torino, INAF, I-10025 Pino Torinese, TO, Italy. Metsahovi Radio Observ, Kylmala 02540, Finland. Univ Perugia, Dipartimento Fis, I-06123 Perugia, Italy. Univ Insubria, Dipartimento Matemat & Fis, I-22100 Como, Italy. European Space Agcy, ESTEC, RSSD, NL-2200 AG Noordwijk, Netherlands. Acad Sci Czech Republ, Inst Astron, CS-25165 Ondrejov, Czech Republic. RP Pian, EP (reprint author), Osserv Astron Trieste, INAF, Via GB Tiepolo 11, I-34131 Trieste, Italy. EM pian@oats.inaf.it RI Gehrels, Neil/D-2971-2012; Foschini, Luigi/H-3833-2012; Tosti, Gino/E-9976-2013; Hudec, Rene/G-9018-2014; OI Foschini, Luigi/0000-0001-8678-0324; Raiteri, Claudia Maria/0000-0003-1784-2784; Persic, Massimo/0000-0003-1853-4900; Villata, Massimo/0000-0003-1743-6946; Malaguti, Giuseppe/0000-0001-9872-3378; Ghisellini, Gabriele/0000-0002-0037-1974; giommi, paolo/0000-0002-2265-5003; Tagliaferri, Gianpiero/0000-0003-0121-0723; Pian, Elena/0000-0001-8646-4858 NR 46 TC 56 Z9 57 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2006 VL 449 IS 2 BP L21 EP L25 DI 10.1051/0004-6361:200600017 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 024MH UT WOS:000236198600004 ER PT J AU Zheng, W Overzier, RA Bouwens, RJ White, RL Ford, HC Benitez, N Blakeslee, JP Bradley, LD Jee, MJ Martel, AR Mei, S Zirm, AW Illingworth, GD Clampin, M Hartig, GF Ardila, DR Bartko, F Broadhurst, TJ Brown, RA Burrows, CJ Cheng, ES Cross, NJG Demarco, R Feldman, PD Franx, M Golimowski, DA Goto, T Gronwall, C Holden, B Homeier, N Infante, L Kimble, RA Krist, JE Lesser, MP Menanteau, F Meurer, GR Miley, GK Motta, V Postman, M Rosati, P Sirianni, M Sparks, WB Tran, HD Tsvetanov, ZI AF Zheng, W Overzier, RA Bouwens, RJ White, RL Ford, HC Benitez, N Blakeslee, JP Bradley, LD Jee, MJ Martel, AR Mei, S Zirm, AW Illingworth, GD Clampin, M Hartig, GF Ardila, DR Bartko, F Broadhurst, TJ Brown, RA Burrows, CJ Cheng, ES Cross, NJG Demarco, R Feldman, PD Franx, M Golimowski, DA Goto, T Gronwall, C Holden, B Homeier, N Infante, L Kimble, RA Krist, JE Lesser, MP Menanteau, F Meurer, GR Miley, GK Motta, V Postman, M Rosati, P Sirianni, M Sparks, WB Tran, HD Tsvetanov, ZI TI An overdensity of galaxies near the most distant radio-loud quasar SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : high-redshift; large-scale structure of universe; quasars : individual (SDSS J0836+0054) ID ULTRA DEEP FIELD; LYMAN-BREAK GALAXIES; DIGITAL SKY SURVEY; LY-ALPHA EMITTERS; LUMINOUS QUASARS; ADVANCED CAMERA; STAR-FORMATION; DISCOVERY; REDSHIFT; CLUSTERS AB A 5 arcmin(2) region around the luminous radio-loud quasar SDSS J0836+0054 (z = 5.8) hosts a wealth of associated galaxies, characterized by very red (1: 3 < i(775) similar to z(850) < 2: 0) color. The surface density of these z similar to 5: 8 candidates is approximately 6 times higher than the number expected from deep ACS fields. This is one of the highest galaxy overdensities at high redshifts, which may develop into a group or cluster. We also find evidence for a substructure associated with one of the candidates. It has two very faint companion objects within 200, which are likely to merge. The finding supports the results of a recent simulation, which finds that luminous quasars at high redshifts lie on the most prominent dark matter filaments and are surrounded by many fainter galaxies. The quasar activity from these regions may signal the buildup of a massive system. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CSIC, Inst Astrofis Andalucia, E-18008 Granada, Spain. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, IPAC, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Bartko Sci & Technol, Brighton, CO 80602 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Metajiva, Edmonds, WA 98026 USA. Conceptual Analyt LLC, Glenn Dale, MD 20769 USA. Royal Observ, Edinburgh EH9 3HJ, Midlothian, Scotland. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 22, Chile. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. European So Observ, D-85748 Garching, Germany. WM Keck Observ, Kamuela, HI 96743 USA. RP Zheng, W (reprint author), Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA. RI White, Richard/A-8143-2012; Clampin, mark/D-2738-2012; Kimble, Randy/D-5317-2012; OI Benitez, Narciso/0000-0002-0403-7455; Blakeslee, John/0000-0002-5213-3548 NR 32 TC 37 Z9 37 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2006 VL 640 IS 2 BP 574 EP 578 DI 10.1086/500167 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026RR UT WOS:000236360300004 ER PT J AU Schwartz, DA Marshall, HL Lovell, JEJ Murphy, DW Bicknell, GV Birkinshaw, M Gelbord, J Georganopoulos, M Godfrey, L Jauncey, DL Perlman, ES Worrall, DM AF Schwartz, DA Marshall, HL Lovell, JEJ Murphy, DW Bicknell, GV Birkinshaw, M Gelbord, J Georganopoulos, M Godfrey, L Jauncey, DL Perlman, ES Worrall, DM TI Chandra observations of magnetic fields and relativistic beaming in four quasar jets SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : jets; quasars : general; X-rays : galaxies ID X-RAY JET; ACTIVE GALACTIC NUCLEI; LARGE-SCALE JETS; HUBBLE-SPACE-TELESCOPE; EXTENDED RADIO JETS; SYNCHROTRON RADIATION; 3C-273; CONNECTION; EMISSION; COMPTON AB We discuss the physical properties of four quasar jets imaged with the Chandra X-Ray Observatory in the course of a survey for X-ray emission from radio jets (Marshall et al.). These objects have sufficient counts to study their spatially resolved properties, even in the 5 ks survey observations. We have acquired Australia Telescope Compact Array data with resolution matching Chandra. We have searched for optical emission with Magellan, with sub-arcsecond resolution. The radio to X-ray spectral energy distribution for most of the individual regions indicates against synchrotron radiation from a single-component electron spectrum. We therefore explore the consequences of assuming that the X-ray emission is the result of inverse Compton scattering on the cosmic microwave background. If particles and magnetic fields are near minimum energy density in the jet rest frames, then the emitting regions must be relativistically beamed, even at distances of order 500 kpc from the quasar. We estimate the magnetic field strengths, relativistic Doppler factors, and kinetic energy flux as a function of distance from the quasar core for two or three distinct regions along each jet. We develop, for the first time, estimates in the uncertainties in these parameters, recognizing that they are dominated by our assumptions in applying the standard synchrotron minimum energy conditions. The kinetic power is comparable with, or exceeds, the quasar radiative luminosity, implying that the jets are a significant factor in the energetics of the accretion process powering the central black hole. The measured radiative efficiencies of the jets are of order 10(-4). C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. CSIRO, Australia Telescope Natl Facil, Epping, NSW 1710, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT 72611, Australia. Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, Baltimore, MD 21250 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM das@head-cfa.harvard.edu RI Godfrey, Leith/B-5283-2013 NR 47 TC 27 Z9 27 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2006 VL 640 IS 2 BP 592 EP 602 DI 10.1086/500102 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026RR UT WOS:000236360300006 ER PT J AU Treu, T Koopmans, LV Bolton, AS Burles, S Moustakas, LA AF Treu, T Koopmans, LV Bolton, AS Burles, S Moustakas, LA TI The sloan lens acs survey. II. Stellar populations and internal structure of early-type lens galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : elliptical and lenticular, cD; galaxies : evolution; galaxies : formation; galaxies : structure; gravitational lensing ID DIGITAL SKY SURVEY; FIELD ELLIPTIC GALAXIES; SPECTROSCOPIC TARGET SELECTION; DYNAMICALLY HOT GALAXIES; DARK-MATTER HALOS; TO-LIGHT RATIOS; FUNDAMENTAL PLANE; GRAVITATIONAL LENS; INTERMEDIATE-REDSHIFT; RED GALAXIES AB We use HST images to derive effective radii and effective surface brightnesses of 15 early-type (E+S0) lens galaxies identified by the SLACS Survey. Our measurements are combined with stellar velocity dispersions from the SDSS database to investigate for the first time the distribution of lens galaxies in the fundamental plane ( FP) space. Accounting for selection effects ( top priority to the largest Einstein radii and thus approximately to the largest velocity dispersions, sigma greater than or similar to 240 km s(-1)) and for passive evolution, the distribution of the lens galaxies inside the FP is indistinguishable from that of the parent sample of SDSS galaxies. We conclude that SLACS lenses are a fair sample of high velocity dispersion E+S0s. By comparing the central stellar velocity dispersion (sigma) with the velocity dispersion that best fits the lensing models (sigma(SIE)) we find < f(SIE)> equivalent to = 1.01 +/- 0.02 with 0.065 rms scatter. We infer that within the Einstein radii (typically R(e)/2) the SLACS lenses are very well approximated by isothermal ellipsoids, requiring a fine tuning of the stellar and dark matter distribution (the bulge-halo "conspiracy''). Interpreting the offset from the local FP in terms of evolution of the stellar mass-to-light ratio, we find d log (M/L(B))/dz = - 0.69 +/- 0.08 (rms 0.11) consistent with the rate found for field E+S0s and with most of the stars being old (z(f) > 2) and less than similar to 10% of the stellar mass having formed below z = 1. We discuss our results in the context of formation mechanisms such as collisionless ("dry'') mergers. C1 Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Treu, T (reprint author), Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. EM tt@physics.ucsb.edu; koopmans@astro.rug.nl; bolton@alum.mit.edu; burles@mit.edu; leonidas@jpl.nasa.gov OI Moustakas, Leonidas/0000-0003-3030-2360 NR 92 TC 148 Z9 149 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2006 VL 640 IS 2 BP 662 EP 672 DI 10.1086/500124 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026RR UT WOS:000236360300011 ER PT J AU Remijan, AJ Hollis, JM AF Remijan, AJ Hollis, JM TI IRAS 16293-2422: Evidence for infall onto a counterrotating protostellar accretion disk SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : clouds; ISM : individual (IRAS 16293-2422); ISM : molecules; radio lines : ISM ID MASS STAR-FORMATION; ASTROPHYSICAL INTEREST; MICROWAVE-SPECTRA; FORMIC-ACID; MOLECULES; MILLIMETER; RESOLUTION; ENVELOPE; ARRAY AB We report high spatial resolution VLA observations of the low-mass star-forming region IRAS 16293 - 2422 using four molecular probes: ethyl cyanide (CH3CH2CN), methyl formate (CH3OCHO), formic acid (HCOOH), and the ground vibrational state of silicon monoxide (SiO). Ethyl cyanide emission has a spatial scale of similar to 20 '' and encompasses binary cores A and B as determined by continuum emission peaks. Surrounded by formic acid emission, methyl formate emission has a spatial scale of similar to 6 '' and is confined to core B. SiO emission shows two velocity components with spatial scales less than 2 '' that map similar to 2 '' northeast of the A and B symmetry axis. The redshifted SiO is similar to 2 '' northwest of blueshifted SiO along a position angle of similar to 135 degrees which is approximately parallel to the A and B symmetry axis. We interpret the spatial position offset in red- and blueshifted SiO emission as due to rotation of a protostellar accretion disk, and we derive similar to 1.4 M-circle dot interior to the SiO emission. In the same vicinity, Mundy et al. also concluded rotation of a nearly edge-on disk from OVRO observations of much stronger and ubiquitous (CO)-C-13 emission, but the direction of rotation is opposite to the SiO emission findings. Taken together, SiO and 13CO data suggest evidence for a counterrotating disk. Moreover, archival BIMA array (CO)-C-12 data show an inverse P Cygni profile with the strongest absorption in close proximity to the SiO emission, indicating unambiguous material infall toward the counterrotating protostellar disk at a new source location within the IRAS 16293 - 2422 complex. The details of these observations and our interpretations are discussed. C1 NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. RP Remijan, AJ (reprint author), Natl Radio Astron Observ, 520 Edgemont Rd, Charlottesville, VA 22903 USA. NR 23 TC 35 Z9 35 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2006 VL 640 IS 2 BP 842 EP 848 DI 10.1086/500239 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026RR UT WOS:000236360300024 ER PT J AU Morris, PW Stolovy, S Wachter, S Noriega-Crespo, A Pannuti, TG Hoard, DW AF Morris, PW Stolovy, S Wachter, S Noriega-Crespo, A Pannuti, TG Hoard, DW TI Tentative discovery of a new supernova remnant in Cepheus: Unveiling an elusive shell in the Spitzer Galactic First Look Survey SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; infrared : ISM; ISM : individual (SSTGFLS J222557+601148) ID INFRARED SPECTROGRAPH IRS; PLANETARY-NEBULAE; SPACE-TELESCOPE; ABSORPTION-LINES; CENTRAL STARS; SN-1006; SPECTROSCOPY; G327.6+14.6; ABUNDANCES; EMISSION AB We have discovered an axially symmetric, well-defined shell of material in the constellation of Cepheus, based on imaging acquired as part of the Galactic First Look Survey with the Spitzer Space Telescope. The 86" x 75" object exhibits brightened limbs on the minor axis and is clearly visible at 24 mu m, but it is not detected in the 3.6, 4.5, 5.8, 8.0, 70, or 160 mu m images. Follow-up 7.5-40 mu m spectroscopy reveals that the shell is composed entirely of ionized gas and that the 24 mu m imaging traces [O IV] 25.89 mu m emission solely. The spectrum also exhibits weaker [Ne III] and [S III] emission, and very weak [Ne V] emission. No emission from warm dust is detected. Spectral cuts through the center of the shell and at the northern limb are highly consistent with each other. The progenitor is not readily identified, but with scaling arguments and comparison to well-known examples of evolved stellar objects, we find the observations to be most straightforward to interpret in terms of a young supernova remnant located at a distance of at least 10 kpc, some 400 pc above the Galactic disk. If confirmed, this would be the first supernova remnant discovered initially at infrared wavelengths. C1 CALTECH, NASA, Herschel Sci Ctr, IPAC, Pasadena, CA 91125 USA. CALTECH, IPAC, Spitzer Sci Ctr, Pasadena, CA 91125 USA. RP Morris, PW (reprint author), CALTECH, NASA, Herschel Sci Ctr, IPAC, M-C 100-22, Pasadena, CA 91125 USA. EM pmorris@ipac.caltech.edu NR 28 TC 21 Z9 21 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2006 VL 640 IS 2 BP L179 EP L182 DI 10.1086/503669 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026RU UT WOS:000236360600018 ER PT J AU Wen, LQ Levine, AM Corbet, RHD Bradt, HV AF Wen, LQ Levine, AM Corbet, RHD Bradt, HV TI A systematic search for periodicities in RXTE ASM data SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE binaries : general; X-rays : stars ID X-RAY BINARY; PULSAR SAX J2103.5+4545; LONG-TERM OBSERVATIONS; TIME-SERIES ANALYSIS; CLUSTER NGC 6624; ORBITAL PERIOD; SMC X-1; 2S 0114+650; OPTICAL OBSERVATIONS; EXOSAT OBSERVATIONS AB We present the results of a systematic search in 8.5 yr of Rossi X-Ray Timing Explorer All-Sky Monitor data for evidence of periodicities. The search was conducted by application of the Lomb-Scargle periodogram to the light curves of each of 458 actually or potentially detected sources in each of four energy bands ( 1.5 - 3, 3 - 5, 5 - 12, and 1.5 - 12 keV). A whitening technique was applied to the periodograms before evaluation of the statistical significance of the powers. We discuss individual detections with a focus on relatively new findings. C1 Max Planck Inst Gravitat Phys, D-14476 Golm, Germany. MIT, Ctr Space Res, Cambridge, MA 02139 USA. NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, XRay Astrophys Lab, Greenbelt, MD 20771 USA. RP Max Planck Inst Gravitat Phys, Albert Einstein Inst,Muhlenberg 1, D-14476 Golm, Germany. EM lwen@aei.mpg.de; aml@space.mit.edu; corbet@gsfc.nasa.gov; hale@space.mit.edu NR 117 TC 73 Z9 74 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 EI 1538-4365 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD APR PY 2006 VL 163 IS 2 BP 372 EP 392 DI 10.1086/500648 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 034VG UT WOS:000236958100007 ER PT J AU Jahoda, K Markwardt, CB Radeva, Y Rots, AH Stark, MJ Swank, JH Strohmayer, TE Zhang, W AF Jahoda, K Markwardt, CB Radeva, Y Rots, AH Stark, MJ Swank, JH Strohmayer, TE Zhang, W TI Calibration of the Rossi X-Ray Timing Explorer proportional counter array SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE instrumentation : detectors; space vehicles : instruments ID FULL-ENERGY ABSORPTION; XENON GAS DETECTORS; GASEOUS XENON; CASSIOPEIA-A; PERFORMANCE; PCA; NONLINEARITY; SIMULATION; SPECTRUM; PULSARS AB We present the calibration and background model for the Proportional Counter Array on board the Rossi X-Ray Timing Explorer. The energy calibration is systematics-limited below 10 keV, with deviations from a power-law fit to the Crab Nebula plus pulsar of less than 1%. Unmodeled variations in the instrumental background amount to less than 2% of the observed background below 10 keV and less than 1% between 10 and 20 keV. Individual photon arrival times are accurate to 4.4 mu s at all times during the mission and to 2.5 mu s after 1997 April 29. The peak pointing direction of the five collimators is known to a precision of a few arcseconds. C1 NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Connecticut Coll, Dept Phys & Astron, New London, CT 06320 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lafayette Coll, Dept Phys, Easton, PA 18042 USA. RP Jahoda, K (reprint author), NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Code 662, Greenbelt, MD 20771 USA. RI Jahoda, Keith/D-5616-2012; Swank, Jean/F-2693-2012; OI Rots, Arnold/0000-0003-2377-2356 NR 38 TC 340 Z9 341 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD APR PY 2006 VL 163 IS 2 BP 401 EP 423 DI 10.1086/500659 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 034VG UT WOS:000236958100009 ER PT J AU Hamilton, DR Murray, JD Ball, CG AF Hamilton, DR Murray, JD Ball, CG TI Cardiac health for astronauts: Coronary calcification scores and CRP as criteria for selection and retention SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Review DE astronaut; c-reactive protein; cholesterol; coronary artery disease; electron-beam computed tomography; risk factors; spaceflight; space exploration; Moon; Mars; International Space Station ID C-REACTIVE PROTEIN; BEAM COMPUTED-TOMOGRAPHY; AMERICAN-HEART-ASSOCIATION; ATHEROSCLEROTIC CARDIOVASCULAR-DISEASE; DENSITY-LIPOPROTEIN CHOLESTEROL; ARTERY CALCIUM SCORE; MULTIDETECTOR ROW CT; ELECTRON-BEAM; INTRAVASCULAR ULTRASOUND; PRIMARY PREVENTION AB Due to the limited treatment and return capabilities of most space vehicles, an in-flight cardiac event could result in significant mission impact or even failure. The current literature supports including electron-beam computed tomography (EBCT) and highly selective C-reactive protein (hsCRP) for diagnosis of coronary artery disease (CAD) in asymptomatic, low-pretest probability cohorts. This paper will examine the issues surrounding adding these tests to astronaut retention and selection algorithms. An evidenced-based literature review was performed and consensus obtained from subject-matter experts to create novel cardiac screening algorithms for astronaut applicants and the current astronaut corps. The main focus of this paper is to derive an evidenced-based approach for improving the diagnosis of significant CAD using EBCT and hsCRP testing. The recommended initial astronaut selection and long-duration mission assignment screening algorithms use EBCT-derived calcium scores and serum hsCRP levels to screen for CAD and predict individual cardiac risk. The current medical evidence is compelling for the international space medicine community to consider: 1.) Astronaut candidates with a coronary artery calcium score > 0 should be disqualified from initial selection; 2.) Astronauts with a coronary artery calcium score > 100 should be disqualified from selection for long-duration missions; 3.) Elevated hsCRP is a reliable risk factor for helping predict future cardiac events that should warrant primary prevention but not necessarily medical disqualification. C1 NASA, Wyle Labs, Adv Projects, Houston, TX 77058 USA. Univ Calgary, Dept Surg, Calgary, AB, Canada. Univ Calgary, Dept Crit Care Med, Foothills Hosp, Calgary, AB, Canada. RP Hamilton, DR (reprint author), NASA, Wyle Labs, Adv Projects, 1290 Hercules Dr,Ste 120, Houston, TX 77058 USA. EM dhamilton@wylehou.com NR 83 TC 6 Z9 9 U1 0 U2 3 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD APR PY 2006 VL 77 IS 4 BP 377 EP 387 PG 11 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 031OC UT WOS:000236712900001 PM 16676648 ER PT J AU Platts, SH Ziegler, MG Waters, WW Meck, JV AF Platts, SH Ziegler, MG Waters, WW Meck, JV TI Hemodynamic effects of midodrine after spaceflight in astronauts without orthostatic hypotension SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE orthostatic intolerance; microgravity; alpha-1 adrenergic agonist; de-glymidodrine ID NEURALLY-MEDIATED SYNCOPE; AUTONOMIC FAILURE; DURATION SPACEFLIGHT; AGONIST MIDODRINE; FLIGHT; INTOLERANCE AB Introduction: Orthostatic hypotension and presyncope are common and potentially serious risks for astronauts returning from space. Susceptible subjects fail to generate an adequate adrenergic response to upright posture. The alpha-1 adrenergic agonist, midodrine, may be an effective countermeasure. We tested the hypothesis that midodrine would have no negative hemodynamic effect on healthy astronauts returning from space. Methods: Five male astronauts participated in preflight and postflight tilt testing on a control flight as well as on the test flights, where midodrine (10 mg, orally) was administered after landing similar to 1 h before testing. Results: None of these astronauts exhibited orthostatic hypotension or presyncope before or after either flight. Midodrine did not cause any untoward reactions in these subjects before or after flight; in fact, a modest beneficial effect was seen on postflight tachycardia (p = 0.036). Discussion: These data show that midodrine protected against post-spaceflight increases in heart rate without having any adverse hemodynamic effects on non-presyncopal, male astronauts. Among these subjects, midodrine was a safe cardiovascular countermeasure. C1 NASA, Lyndon B Johnson Space Ctr SK32, Space Life Sci Res Labs, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Univ Space Res Assoc, Houston, TX USA. Wyle Labs Inc, Houston, TX USA. RP Meck, JV (reprint author), NASA, Lyndon B Johnson Space Ctr SK32, Space Life Sci Res Labs, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. EM jmeck@ems.jsc.nasa.gov FU NCRR NIH HHS [M01RR00827] NR 24 TC 3 Z9 4 U1 1 U2 2 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD APR PY 2006 VL 77 IS 4 BP 429 EP 433 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 031OC UT WOS:000236712900008 PM 16676655 ER PT J AU Fuglesang, C Narici, L Picozza, P Sannita, WG AF Fuglesang, C Narici, L Picozza, P Sannita, WG TI Phosphenes in low earth orbit: Survey responses from 59 astronauts SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE phosphenes; spaceflight; radiation; high energy particles ID LIGHT-FLASHES; COSMIC-RADIATION; SPACE-STATION; ALTEA; IONS; EYE AB Introduction: It has long been known that many people in space experience sudden phosphenes, or light flashes. Although it is clear that they are related to high-energy particles in the space radiation environment, many details about them are still unknown. In an effort to gain more knowledge about the light flashes, a study was initiated to collect information from people who have recently flown in space. Method: A survey conducted by anonymous questionnaire was performed among astronauts regarding their experience of sudden light flashes in space. In all, 98 surveys were distributed to current NASA and ESA astronauts. Results: Among the 59 respondents, 47 noticed them sometime during spaceflight. Most often they were noted before sleep, and several people even thought the light flashes disturbed their sleep. The light flashes predominantly appear white, have elongated shapes, and most interestingly, often come with a sense of motion. The motion is described as sideways, diagonal, or in-out, but never in the vertical direction. Discussion: Comparisons with earlier studies of light flashes in space and several ground-based studies during the 1970s are made. One interesting observation from this is that it seems that a small fraction of the light flashes is caused by Cherenkov radiation, while the majority is probably caused by some kind of direct interaction with elements in the retina. C1 ESA, European Astronaut Ctr, Cologne, Germany. Univ Roma Tor Vergata, Dept Phys, Rome, Italy. Ist Nazl Fis Nucl, Sez Roma 2, Rome, Italy. Univ Genoa, Dept Motor Sci & Rehabil, Genoa, Italy. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Fuglesang, C (reprint author), NASA, Lyndon B Johnson Space Ctr, Mailcode CB,2101 NASA Pkwy, Houston, TX 77058 USA. EM christer.fugle-sang-1@nasa.gov OI Picozza, Piergiorgio/0000-0002-7986-3321 NR 21 TC 17 Z9 17 U1 0 U2 3 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD APR PY 2006 VL 77 IS 4 BP 449 EP 452 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 031OC UT WOS:000236712900012 PM 16676658 ER PT J AU Mehta, VM Lindstrom, EJ de Kort, L DeCandis, AJ AF Mehta, VM Lindstrom, EJ de Kort, L DeCandis, AJ TI The virtual center for decadal climate variability SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article C1 Ctr Res Changing Earth Syst, Columbia, MD 21044 USA. NASA, Ocean Phys Program, Earth Sun Syst Div, Sci Mission Directorate, Washington, DC 20546 USA. RP Mehta, VM (reprint author), Ctr Res Changing Earth Syst, 10211 Wincopin Circle,Suite 240, Columbia, MD 21044 USA. EM vikram@crces.org NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD APR PY 2006 VL 87 IS 4 BP 421 EP 424 DI 10.1175/BAMS-87-4-421 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 036CT UT WOS:000237049200014 ER PT J AU Waliser, D Weickmann, K Dole, R Schubert, S Alves, O Jones, C Newman, M Pan, HL Roubicek, A Saha, S Smith, C van den Dool, H Vitart, F Wheeler, M Whitaker, J AF Waliser, D Weickmann, K Dole, R Schubert, S Alves, O Jones, C Newman, M Pan, HL Roubicek, A Saha, S Smith, C van den Dool, H Vitart, F Wheeler, M Whitaker, J TI The experimental MJO prediction project SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NOAA, Div Phys Sci, Earth Syst Res Lab, Boulder, CO USA. NASA, Global Model & Assimilat Off, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Bur Meteorol Res Ctr, Ocean & Marine Forecasting Grp, Melbourne, Vic, Australia. Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, Santa Barbara, CA 93106 USA. Univ Colorado, CIRES Climate Diagnost Ctr, Boulder, CO 80309 USA. NOAA, NCEP, Environm Modeling Ctr, Camp Springs, MD USA. NOAA, NCEP, Climate Predict Ctr, Camp Springs, MD USA. European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. Bur Meteorol Res Ctr, Climate Forecasting Grp, Melbourne, Vic, Australia. RP Waliser, D (reprint author), CALTECH, Jet Prop Lab, MS 183-505,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM duane.waliser@jpl.nasa.gov RI Newman, Matthew /F-8336-2010; Wheeler, Matthew/C-9038-2011; Smith, Catherine/H-5055-2016; OI Newman, Matthew /0000-0001-5348-2312; Wheeler, Matthew/0000-0002-9769-1973; Smith, Catherine/0000-0003-2687-6046; Jones, Charles/0000-0003-4808-6977 NR 8 TC 31 Z9 34 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD APR PY 2006 VL 87 IS 4 BP 425 EP 431 DI 10.1175/BAMS-87-4-425 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 036CT UT WOS:000237049200015 ER PT J AU Li, Z Gray, A Love, M Asahida, T Gharrett, A AF Li, Z Gray, A Love, M Asahida, T Gharrett, A TI Phylogeny of members of the rockfish (Sebastes) subgenus Pteropodus and their relatives SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID 3 COLOR MORPHOTYPES; GENUS SEBASTES; RESTRICTION DATA; SCORPAENIDAE; IDENTIFICATION; INERMIS AB The Sebastes Cuvier, 1829 subgenus Pteropodus Eigenmann and Beeson, 1893 includes six species from the northeastern Pacific Ocean (NEP) and four species from the northwestern Pacific Ocean (NWP). Several NEP species assigned to other subgenera are similar to NEP Pteropodus species. Restriction site variation in the mitochondrial NADH dehydrogenase subunit 3 and 4 genes and the 12S and 16S ribosomal RNA genes were used to evaluate their relationships. Phylogenetic reconstruction showed that six NEP species of Pteropodus formed a monophyletic group that also included three NEP species currently assigned to other subgenera: Sebastes atrovirens (Jordan and Gilbert, 1880) (subgenus Mebarus Matsubara, 1943) and Sebastes auriculatus Girard, 1854 and Sebastes dalli (Eigenmann and Beeson, 1894) (both subgenus Auctospina (Eigenmann and Beeson, 1894)). The small average nucleotide divergence (0.0124 per nucleotide) observed among members of this group of species was similar to that observed among species of the monophyletic subgenus Sebastomus Gill, 1864 (0.0089 per nucleotide). The NWP species of Pteropodus did not cluster with their NEP consubgeners but, generally, were similar to other NWP species. We recommend that S. atrovirens, S. auriculatus, and S. dalli be included in subgenus Pteropodus with the other NEP species and that the NWP species of Pteropodus be removed from the subgenus. Our results indicate that the morphological characteristics used to distinguish species often may not be useful for phylogenetic analysis. C1 Univ Alaska, Sch Fisheries & Ocean Sci, Juneau Ctr, Juneau, AK 99801 USA. Univ Calif Santa Barbara, Inst Marine Sci, Santa Barbara, CA 93106 USA. Kitasato Univ, Sch Fisheries Sci, Ofunato, Iwate 0220101, Japan. RP Li, Z (reprint author), Natl Marine Fisheries Serv, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. EM ffajg@uaf.edu NR 34 TC 8 Z9 8 U1 1 U2 7 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD APR PY 2006 VL 84 IS 4 BP 527 EP 536 DI 10.1139/Z06-022 PG 10 WC Zoology SC Zoology GA 054DF UT WOS:000238356300005 ER PT J AU Toutanji, HA Fiske, MR Bodiford, MP AF Toutanji, HA Fiske, MR Bodiford, MP TI Moondust and more SO CIVIL ENGINEERING LA English DT Article; Proceedings Paper CT Earth and Space 2006 Conference CY MAR, 2006 CL Houston, TX SP ASCE C1 Univ Alabama, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Toutanji, HA (reprint author), Univ Alabama, Huntsville, AL 35899 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0885-7024 J9 CIVIL ENG JI Civil Eng. PD APR PY 2006 VL 76 IS 4 BP 64 EP 69 PG 6 WC Engineering, Civil SC Engineering GA 030TS UT WOS:000236658200023 ER PT J AU Bodiford, MP Burks, KH Perry, MR Cooper, RW Fiske, MR AF Bodiford, MP Burks, KH Perry, MR Cooper, RW Fiske, MR TI Moondust and more SO CIVIL ENGINEERING LA English DT Article C1 NASA, MSFC, Huntsville, AL USA. Jacobs Sverdrup, Huntsville, AL USA. RP Bodiford, MP (reprint author), NASA, MSFC, Huntsville, AL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0885-7024 J9 CIVIL ENG JI Civil Eng. PD APR PY 2006 VL 76 IS 4 BP 65 EP + PG 4 WC Engineering, Civil SC Engineering GA 030TS UT WOS:000236658200024 ER PT J AU Masson-Delmotte, V Kageyama, M Braconnot, P Charbit, S Krinner, G Ritz, C Guilyardi, E Jouzel, J Abe-Ouchi, A Crucifix, M Gladstone, RM Hewitt, CD Kitoh, A LeGrande, AN Marti, O Merkel, U Motoi, T Ohgaito, R Otto-Bliesner, B Peltier, WR Ross, I Valdes, PJ Vettoretti, G Weber, SL Wolk, F Yu, Y AF Masson-Delmotte, V Kageyama, M Braconnot, P Charbit, S Krinner, G Ritz, C Guilyardi, E Jouzel, J Abe-Ouchi, A Crucifix, M Gladstone, RM Hewitt, CD Kitoh, A LeGrande, AN Marti, O Merkel, U Motoi, T Ohgaito, R Otto-Bliesner, B Peltier, WR Ross, I Valdes, PJ Vettoretti, G Weber, SL Wolk, F Yu, Y TI Past and future polar amplification of climate change: climate model intercomparisons and ice-core constraints SO CLIMATE DYNAMICS LA English DT Article ID LAST GLACIAL MAXIMUM; SEA-ICE; SYNERGISTIC FEEDBACKS; NORTHERN-HEMISPHERE; CENTRAL GREENLAND; SURFACE CLIMATE; SOUTHERN-OCEAN; TEMPERATURE; SENSITIVITY; VEGETATION AB Climate model simulations available from the PMIP1, PMIP2 and CMIP (IPCC-AR4) intercomparison projects for past and future climate change simulations are examined in terms of polar temperature changes in comparison to global temperature changes and with respect to pre-industrial reference simulations. For the mid-Holocene (MH, 6,000 years ago), the models are forced by changes in the Earth's orbital parameters. The MH PMIP1 atmosphere-only simulations conducted with sea surface temperatures fixed to modern conditions show no MH consistent response for the poles, whereas the new PMIP2 coupled atmosphere-ocean climate models systematically simulate a significant MH warming both for Greenland (but smaller than ice-core based estimates) and Antarctica (consistent with the range of ice-core based range). In both PMIP1 and PMIP2, the MH annual mean changes in global temperature are negligible, consistent with the MH orbital forcing. The simulated last glacial maximum (LGM, 21,000 years ago) to pre-industrial change in global mean temperature ranges between 3 and 7 degrees C in PMIP1 and PMIP2 model runs, similar to the range of temperature change expected from a quadrupling of atmospheric CO2 concentrations in the CMIP simulations. Both LGM and future climate simulations are associated with a polar amplification of climate change. The range of glacial polar amplification in Greenland is strongly dependent on the ice sheet elevation changes prescribed to the climate models. All PMIP2 simulations systematically underestimate the reconstructed glacial-interglacial Greenland temperature change, while some of the simulations do capture the reconstructed glacial-interglacial Antarctic temperature change. Uncertainties in the prescribed central ice cap elevation cannot account for the temperature change underestimation by climate models. The variety of climate model sensitivities enables the exploration of the relative changes in polar temperature with respect to changes in global temperatures. Simulated changes of polar temperatures are strongly related to changes in simulated global temperatures for both future and LGM climates, confirming that ice-core-based reconstructions provide quantitative insights on global climate changes. C1 CEA Saclay, CNRS, UMR 1572, LSCE IPSL, F-91191 Gif Sur Yvette, France. UJF, CNRS, UMR 5183, Lab Glaciol & Geophys Environm, St Martin Dheres, France. Univ Tokyo, Ctr Climate Syst Res, Kashiwa, Chiba 2778568, Japan. Hadley Ctr Climate Predict & Res, Met Off, Exeter EX1 3PB, Devon, England. Univ Bristol, Sch Geog Sci, Bristol BS8 1SS, Avon, England. Meterol Res Inst, Climate Res Dept, Tsukuba, Ibaraki 3050052, Japan. Columbia Univ, Ctr Climate Syst, New York, NY USA. Columbia Univ, NASA Goddard Inst Space Studies, New York, NY USA. IFM GEOMAR, D-24105 Kiel, Germany. JAMSTEC, FRCGC, Yokohama, Kanagawa 2360001, Japan. Natl Ctr Atmospher Res, Climate Change Res, Boulder, CO 80307 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. KNMI, Climate Variabil Res, NL-3730 AE De Bilt, Netherlands. Catholic Univ Louvain, Inst Astron & Geophys G Lemaitre, B-1348 Louvain, Belgium. Chinese Acad Sci, Inst Atmospher Phys, LASG, Beijing 10029, Peoples R China. RP Masson-Delmotte, V (reprint author), CEA Saclay, CNRS, UMR 1572, LSCE IPSL, Batiment 701, F-91191 Gif Sur Yvette, France. EM valerie.masson@cea.fr RI Marti, Olivier/B-2378-2009; KAGEYAMA, Masa/F-2389-2010; Ross, Ian/C-8766-2011; Guilyardi, Eric/D-4868-2011; Krinner, Gerhard/A-6450-2011; LeGrande, Allegra/D-8920-2012; Peltier, William/A-1102-2008; Masson-Delmotte, Valerie/G-1995-2011; Gladstone, Rupert/C-1086-2013; Valdes, Paul/C-4129-2013; Abe-Ouchi, Ayako/M-6359-2013; Yu, Yongqiang /K-7808-2012 OI KAGEYAMA, Masa/0000-0003-0822-5880; Guilyardi, Eric/0000-0002-2255-8625; Krinner, Gerhard/0000-0002-2959-5920; LeGrande, Allegra/0000-0002-5295-0062; Masson-Delmotte, Valerie/0000-0001-8296-381X; Gladstone, Rupert/0000-0002-1582-3857; Abe-Ouchi, Ayako/0000-0003-1745-5952; Yu, Yongqiang /0000-0001-8596-3583 NR 72 TC 126 Z9 126 U1 3 U2 44 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD APR PY 2006 VL 26 IS 5 BP 513 EP 529 DI 10.1007/s00382-005-0081-9 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 019VW UT WOS:000235865800005 ER PT J AU Olson, SL Miller, FJ Wichman, IS AF Olson, SL Miller, FJ Wichman, IS TI Characterizing fingering flamelets using the logistic model SO COMBUSTION THEORY AND MODELLING LA English DT Article DE near-limit; fire; flamelets; reduced buoyancy; spread rate; thermally-thin; instability; fingering; combustion; population; logistic model; bifurcation; extinction; time lag ID COMBUSTION; SPREAD; MICROGRAVITY; INSTABILITY AB We apply the logistic equation to a class of flame spread that occurs in near-extinction, weakly convective environments such as microgravity or vertically confined spaces. The flame under these conditions breaks into numerous 'flamelets' which form a Turing-type reaction-diffusion fingering pattern as they spread across the fuel. Flamelets are steady, based on flame spread measurements, and reach a critical state near extinction where a spread rate plateau reflects a critical heat flux for ignition. Our analysis of experiments performed in a buoyancy-reducing, vertically confined flow tunnel reveals the presence of statistical order in the seemingly random patterns. Flamelets as a group form a dynamic population that interacts competitively for the limited available oxygen. Flamelets bifurcate and extinguish individually, but as a whole, the group maintains a stable size. Flamelets show an exponentially decaying lifetime and a uniform pattern of dispersion. We utilize the continuous logistic model with a time lag to describe the flamelet population growth and fluctuation around a stable population characterized by the carrying capacity based on environmental limitations. We discuss how the physics of the system is expressed through the model parameters. C1 NASA, Glenn Res Ctr, Combust & Reacting Syst Branch, Cleveland, OH 44135 USA. Natl Ctr Space Explorat Res, Cleveland, OH 44135 USA. Michigan State Univ, Dept Mech Engn, E Lansing, MI 48824 USA. RP Olson, SL (reprint author), NASA, Glenn Res Ctr, Combust & Reacting Syst Branch, Cleveland, OH 44135 USA. EM sandra.l.olson@nasa.gov NR 22 TC 16 Z9 19 U1 0 U2 7 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1364-7830 J9 COMBUST THEOR MODEL JI Combust. Theory Model. PD APR PY 2006 VL 10 IS 2 BP 323 EP 347 DI 10.1080/13647830600565446 PG 25 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Mathematics, Interdisciplinary Applications SC Thermodynamics; Energy & Fuels; Engineering; Mathematics GA 055LN UT WOS:000238452300007 ER PT J AU Lien, MC Ruthruff, E Johnston, JC AF Lien, MC Ruthruff, E Johnston, JC TI Attentional limitations in doing two tasks at once - The search for exceptions SO CURRENT DIRECTIONS IN PSYCHOLOGICAL SCIENCE LA English DT Article DE dual-task interference; central bottleneck ID PSYCHOLOGICAL REFRACTORY-PERIOD; DUAL-TASK; INTERFERENCE; PERFORMANCE; BOTTLENECK AB People generally have difficulty doing two tasks at once. To explain this fact, theorists have proposed that central processing-the thought-like stages following perceptual encoding and preceding response processing-takes place for only one task at a time. Because this bottleneck imposes severe limits on human cognitive processes, research has attempted to find exceptions. There is now solid evidence that, at least in the laboratory, the entire bottleneck can be completely bypassed under favorable combinations of circumstances. While these findings provide a ray of hope for enabling parallel multitasking in real-world scenarios, it will not be easy to take advantage of the combination of conditions that appear to be necessary. C1 Oregon State Univ, Dept Psychol, Corvallis, OR 97331 USA. Univ New Mexico, Albuquerque, NM 87131 USA. NASA, Ames Res Ctr, Washington, DC 20546 USA. RP Lien, MC (reprint author), Oregon State Univ, Dept Psychol, Corvallis, OR 97331 USA. EM mei.lien@oregonstate.edu NR 17 TC 45 Z9 45 U1 1 U2 19 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0963-7214 J9 CURR DIR PSYCHOL SCI JI Curr. Dir. Psychol. PD APR PY 2006 VL 15 IS 2 BP 89 EP 93 DI 10.1111/j.0963-7214.2006.00413.x PG 5 WC Psychology, Multidisciplinary SC Psychology GA 042GK UT WOS:000237515700009 ER PT J AU Rutledge, SL Shaw, HC Benavides, JB Yowell, LL Chen, Q Jacobs, BW Song, SP Ayres, VM AF Rutledge, S. L. Shaw, H. C. Benavides, J. B. Yowell, L. L. Chen, Q. Jacobs, B. W. Song, S. P. Ayres, V. M. TI Self assembly and correlated properties of electrospun carbon nanofibers SO DIAMOND AND RELATED MATERIALS LA English DT Article; Proceedings Paper CT 16th European Conference on Diamond, Diamond-Like Materials, Carbon Nanotubes, and Nitrides CY SEP 11-16, 2005 CL Toulouse, FRANCE DE nanofibers; scanning probe techniques; mechanical properties; biomaterials AB An investigation of the influence of droplet size conditions and monomer choice on electrospun carbon nanofiber properties is presented. Monomer choices included poly (epsilon-caprolactone) and poly (methyl methacrylate) with and without the addition of single walled carbon nanotubes. A key property under investigation is the effect of electrospinning conditions on the resulting carbon nanofiber elasticity. Carbon nanofiber elasticity investigations are performed using atomic force microscopy with force volume imaging and the Force Integration to Equal Limits mapping method. A monomer choice of poly (F.-caprolactone) with a syringe bore radius of 406.4 microns is shown to produce electrospun carbon nanofibers with acceptable morphologies for tissue scaffold applications. (c) 2006 Elsevier B.V. All rights reserved. C1 Michigan State Univ, Dept Elect & Comp Engn, E Lansing, MI 48824 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Ayres, VM (reprint author), Michigan State Univ, Dept Elect & Comp Engn, E Lansing, MI 48824 USA. EM ayresv@egr.msu.edu NR 10 TC 5 Z9 5 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD APR-AUG PY 2006 VL 15 IS 4-8 SI SI BP 1070 EP 1074 DI 10.1016/j.diamond.2005.11.051 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 065JU UT WOS:000239157000125 ER PT J AU Ayres, VM Jacobs, BW Englund, ME Carey, EH Crimp, MA Ronningen, RM Zeller, AF Halpern, JB He, MQ Harris, GL Liu, D Shaw, HC Petkov, MP AF Ayres, V. M. Jacobs, B. W. Englund, M. E. Carey, E. H. Crimp, M. A. Ronningen, R. M. Zeller, A. F. Halpern, J. B. He, M. -Q. Harris, G. L. Liu, D. Shaw, H. C. Petkov, M. P. TI Investigations of heavy ion irradiation of gallium nitride nanowires and nanocircuits SO DIAMOND AND RELATED MATERIALS LA English DT Article; Proceedings Paper CT 16th European Conference on Diamond, Diamond-Like Materials, Carbon Nanotubes, and Nitrides CY SEP 11-16, 2005 CL Toulouse, FRANCE DE gallium nitride (GaN); radiation-induced effects; high-resolution electron microscopy; nanotechnology ID TRANSPORT-PROPERTIES; GROWTH AB Results of a first investigation of the response of gallium nitride nanowires to high-Z heavy ion irradiation are reported. Pre-irradiation characterization of the gallium nitride nanowires used in these experiments showed that that they had a two-phase coaxial structure, consisting of an outer shell of zinc-blende-phase gallium nitride and a coaxial core of wurtzite-phase gallium nitride. Observed radiation interactions with the two-phase structure are reported. A nanowire-based field effect transistor using these GaN nanowires showed normal real-time operation during irradiation by Krypton-78 heavy ions under high bias conditions. (c) 2006 Elsevier B.V. All rights reserved. C1 Michigan State Univ, Dept Elect & Comp Engn, E Lansing, MI 48824 USA. Howard Univ, Washington, DC 20059 USA. Muniz Engn Inc, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ayres, VM (reprint author), Michigan State Univ, Dept Elect & Comp Engn, E Lansing, MI 48824 USA. EM ayresv@egr.msu.edu NR 11 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD APR-AUG PY 2006 VL 15 IS 4-8 SI SI BP 1117 EP 1121 DI 10.1016/j.diamond.2005.11.055 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 065JU UT WOS:000239157000135 ER PT J AU Van Sluytman, JS West, WC Whitacre, JF Alamgir, FM Greenbaum, SG AF Van Sluytman, JS West, WC Whitacre, JF Alamgir, FM Greenbaum, SG TI Cycling-induced degradation of LiCoO2 thin-film cathodes at elevated temperature SO ELECTROCHIMICA ACTA LA English DT Article DE LiCoO2 thin-film cell; elevated temperature cycling; X-ray diffraction; phase transitions ID LITHIUM; STABILITY; BATTERIES AB The cycle life of LiCoO2-based all solid-state thin-film cells has been studied at room temperature, and at elevated temperatures of 50, 100, and 150 degrees C. X-ray diffraction, as well as Raman analysis, has been used to complement the electrochemical data in examining structural and chemical changes. XRD and Raman spectroscopy data indicate that elevated temperature soaks of the thin-film batteries in the quiescent state causes no discernable changes in the LiCoO2 cathode layer. However, when the thin-film batteries are cycled at elevated temperatures, decreases in average grain size of the LiCoO2 film occur with dramatic concomitant charge and discharge capacity loss. (c) 2005 Elsevier Ltd. All rights reserved. C1 CUNY Hunter Coll, Dept Phys & Astron, New York, NY 10021 USA. CALTECH, Jet Prop Lab, Electrochem Technol Grp, Pasadena, CA 91109 USA. RP Van Sluytman, JS (reprint author), CUNY Hunter Coll, Dept Phys & Astron, 695 Pk Ave, New York, NY 10021 USA. EM Gunner7690@aol.com OI Alamgir, Faisal/0000-0002-0894-8096 NR 16 TC 6 Z9 6 U1 3 U2 23 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 1 PY 2006 VL 51 IS 15 BP 3001 EP 3007 DI 10.1016/j.electacta.2005.08.032 PG 7 WC Electrochemistry SC Electrochemistry GA 033KF UT WOS:000236845200002 ER PT J AU Raffel, M Richard, H Ehrenfried, K Van der Wall, B Burley, C Beaumier, P McAlister, K Pengel, K AF Raffel, M Richard, H Ehrenfried, K Van der Wall, B Burley, C Beaumier, P McAlister, K Pengel, K TI Recording and evaluation methods of PIV investigations on a helicopter rotor model (vol 40, pg 665, 2006) SO EXPERIMENTS IN FLUIDS LA English DT Correction C1 DLR, Inst Aerodynam & Stromungstech, Gottingen, Germany. DLR, Inst Flugsystemtech, Braunschweig, Germany. NASA, Langley Res Ctr, Langley, VA USA. Off Natl Etud & Rech Aerosp, Chatillon, France. NASA, Ames Res Ctr, USA, AFDD, Moffett Field, CA 94035 USA. DNW, Large Low Speed Facil LLF, Nordostpolder, Netherlands. RP Raffel, M (reprint author), DLR, Inst Aerodynam & Stromungstech, Gottingen, Germany. EM markus.raffel@dlr.de NR 1 TC 1 Z9 1 U1 0 U2 6 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD APR PY 2006 VL 40 IS 4 BP 665 EP 665 DI 10.1007/s00348-006-0120-2 PG 1 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 032CT UT WOS:000236752200017 ER PT J AU Paloski, WH Wood, SJ Feiveson, AH Black, FO Hwang, EY Reschke, MF AF Paloski, WH Wood, SJ Feiveson, AH Black, FO Hwang, EY Reschke, MF TI Destabilization of human balance control by static and dynamic head tilts SO GAIT & POSTURE LA English DT Article DE posture; otolith; spatial orientation; vestibulo-spinal; head tilt ID LINEAR ACCELERATION; MOTION; POSTUROGRAPHY; MODEL; DISORDERS; FREQUENCY; POSITION AB To better understand the effects of varying head movement frequencies on human balance control, 12 healthy adult humans were studied during static and dynamic (0.14, 0.33, 0.6 Hz) head tilts of +/- 30 degrees in the pitch and roll planes. Postural sway was measured during upright stance with eyes closed and altered somatosensory inputs provided by a computerized dynamic posturography (CDP) system. Subjects were able to maintain upright stance with static head tilts, although postural sway was increased during neck extension. Postural stability was decreased during dynamic head tilts, and the degree of destabilization varied directly with increasing frequency of head tilt. In the absence of vision and accurate foot support surface inputs, postural stability may be compromised during dynamic head tilts due to a decreased ability of the vestibular system to discern the orientation of gravity. This instability may compound the risk of falling following recovery from balance disorders or adaptation to altered gravity conditions such as space flight. Thus, dynamic head tilts may improve the diagnostic sensitivity of computerized dynamic posturography, particularly for healthy subjects recovering from temporary balance control deficits. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Neurosci Lab, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Univ Space & Res Assoc, Houston, TX USA. Legacy Hlth Syst, Neurotol Res, Portland, OR USA. Wyle Labs, Neurosci Lab, Crew Hlth & Res Dept, Houston, TX USA. RP Paloski, WH (reprint author), NASA, Lyndon B Johnson Space Ctr, Neurosci Lab, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. EM wpaloski@ems.jsc.nasa.gov FU PHS HHS [00205] NR 24 TC 40 Z9 42 U1 0 U2 3 PU ELSEVIER IRELAND LTD PI CLARE PA ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELAND SN 0966-6362 EI 1879-2219 J9 GAIT POSTURE JI Gait Posture PD APR PY 2006 VL 23 IS 3 BP 315 EP 323 DI 10.1016/j.gaitpost.2005.04.009 PG 9 WC Neurosciences; Orthopedics; Sport Sciences SC Neurosciences & Neurology; Orthopedics; Sport Sciences GA 026KL UT WOS:000236337700009 PM 15961313 ER PT J AU Nemchin, AA Whitehouse, MJ Pidgeon, RT Meyer, C AF Nemchin, AA Whitehouse, MJ Pidgeon, RT Meyer, C TI Oxygen isotopic signature of 4.4-3.9 Ga zircons as a monitor of differentiation processes on the Moon SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID LUNAR POLYMICT BRECCIA-14321; GEOCHRONOLOGY; RATIOS; ROCKS; SIMS AB We report oxygen isotopic compositions for 14 zircon grains from a sample of sawdust from lunar breccia 14321. The zircons range in age from similar to 4.4 to 3.9 Ga and in U and Th content from a few to several hundred ppm. As such these grains represent a range of possible source rocks, from granophyric to mafic composition, and cover the total age range of the major initial lunar bombardment. Nevertheless, results show that the oxygen isotopic compositions of the zircons fall within a narrow range of delta O-18 of about 1 per mil and have delta O-18 values indistinguishable from those observed for terrestrial mid-ocean ridge basalts confirming the coincidence of lunar and Earth oxygen isotopic compositions. In the delta O-17 VS. delta O-18, coordinates data form a tight group with a limited trend on the terrestrial fractionation line. The zircon oxygen isotopes show minimal evidence of the extreme and variable mineral differentiation and element fractionation that have contributed to the formation of their parent rocks. (c) 2006 Elsevier Inc. All rights reserved. C1 Curtin Univ Technol, Western Australian Sch Mines, Bentley, WA 6102, Australia. Swedish Museum Nat Hist, Lab Isotope Geol, SE-10405 Stockholm, Sweden. Curtin Univ Technol, Dept Appl Geol, Bentley, WA 6102, Australia. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Nemchin, AA (reprint author), Curtin Univ Technol, Western Australian Sch Mines, Bentley, WA 6102, Australia. EM nemchina@kalg.curtin.edu.au RI Whitehouse, Martin/E-1425-2013 OI Whitehouse, Martin/0000-0003-2227-577X NR 34 TC 32 Z9 33 U1 0 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD APR 1 PY 2006 VL 70 IS 7 BP 1864 EP 1872 DI 10.1016/j.gca.2005.12.009 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 030OL UT WOS:000236644000021 ER PT J AU Kallmeyer, J Mangelsdorf, K Cragg, B Horsfield, B AF Kallmeyer, Jens Mangelsdorf, Kai Cragg, Barry Horsfield, Brian TI Techniques for contamination assessment during drilling for terrestrial subsurface sediments SO GEOMICROBIOLOGY JOURNAL LA English DT Article DE contamination assessment; terrestrial drilling; rotary drilling; deep biosphere; biomarkers; microspheres ID MICROBIAL-CONTAMINATION; DEEP-SUBSURFACE; HOPANOIC ACIDS; SEA AB Details about the procedures for drilling a ca. 150 m long drill core in a terrestrial setting under contamination controlled conditions are presented. Different to previous studies we only used commercially available drilling equipment to reduce the cost of operation significantly. The goals were (1) to minimize, (2) to monitor and, if possible, to quantify the contamination of the recovered sediments, and (3) to identify the different sources of contamination. Both the potential contamination of the sample material by surface microorganisms and non-indigenous material was assessed. To estimate the infiltration of drill mud into the core, fluorescent microspheres, having about half the size as microorganisms, were added to the mud. The drilling technique used was mud rotary drilling. With the exception of the very beginning of the drilling operations, the drill mud was devoid of any allochthonous hydrocarbons potentially derived from the drilling equipment or drill additives, and its biomarker composition reflected the varying organo-facies that were penetrated. Due to the lack of allochthonous hydrocarbons in the drill mud, its infiltration into the sediment cannot be traced by organic geochemical biomarker analysis. Microspheres proved to be a sensitive tool for the assessment of infiltration of drill mud into the core. The concentration of microspheres in the drill mud decreased continuously during the drilling, most probably caused by seepage of mud through leaks and attachment of spheres to the surface scum in the mud pit. Microscopic enumeration of the microspheres showed great variability in the depth of penetration of mud into the core, apparently unaffected of lithology. The sampling of the core material in the laboratory was carried out inside an anaerobic chamber. Several techniques for subsampling were used, according to sediment properties. The overall results indicate that, if strict contamination control protocols are employed, it is possible to recover uncontaminated samples at reasonable cost with commercially available drilling equipment. C1 Univ Rhode Isl, NASA, Astrobiol Inst, Narragansett, RI 02882 USA. Geoforschungszentrum Potsdam, Telegrafenberg, D-14473 Potsdam, Germany. Univ Cardiff Wales, Dept Earth Ocean & Planetary Sci, Cardiff, Wales. RP Kallmeyer, J (reprint author), Univ Rhode Isl, NASA, Astrobiol Inst, S Ferry Rd, Narragansett, RI 02882 USA. EM kallmeyer@gso.uri.edu RI Kallmeyer, Jens/I-3554-2012; Cragg, Barry/D-2690-2009 OI Kallmeyer, Jens/0000-0002-6440-1140; NR 20 TC 16 Z9 16 U1 1 U2 9 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-0451 J9 GEOMICROBIOL J JI Geomicrobiol. J. PD APR-JUN PY 2006 VL 23 IS 3-4 BP 227 EP 239 DI 10.1080/01490450600724258 PG 13 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 081TQ UT WOS:000240340300009 ER PT J AU Smith, LC Sheng, YW Magilligan, FJ Smith, ND Gomez, B Mertes, LAK Krabill, WB Garvin, JB AF Smith, LC Sheng, YW Magilligan, FJ Smith, ND Gomez, B Mertes, LAK Krabill, WB Garvin, JB TI Geomorphic impact and rapid subsequent recovery from the 1996 Skeioararsandur jokulhlaup, Iceland, measured with multi-year airborne lidar SO GEOMORPHOLOGY LA English DT Article; Proceedings Paper CT 34th Binghamton Geomorphology Symposium CY OCT 03-05, 2003 CL SUNY Binghamton, Binghamton, NY HO SUNY Binghamton DE Iceland; Skeioararsandur; Vatnajokull; Jokulhlaup; flood; erosion; lidar; DEM; remote sensing ID ICE; SKEIDARARJOKULL; VATNAJOKULL; DEPOSITION; CHANNEL; FLOODS AB The November 1996 jokulhlaup that burst from the Vatnajokull ice cap onto Skeidararsandur was the highest-magnitude flood ever measured on the largest active glacial outwash plain (sandur). Centimeter-scale elevation transects, measured from repeat-pass airborne laser altimetry missions flown in 1996 (pre-flood), 1997, and 200 1, show that sediment deposition exceeded erosion across the central Skeidararsandur and established an average net elevation gain of +22 cm for the event. Net elevation gains of +29 and +24 cm occurred in braided channels of the Gigjuk-visl and Skeidara rivers, respectively. Nearly half of these gains, however, were removed within 4 years, and the two rivers contrast strongly in style of erosional/depositional impact and subsequent recovery. In the Gigjukvisl, the 1996 jokulhlaup caused massive sediment deposition (up to similar to 12 m) near the ice margin and intense "mega-forming" of braided channels and bars downstream. Post-jokulhlaup recovery (1997-2001) was characterized by rapid erosion (-0.5 m) of ice-proximal sediments and their transport to downstream reaches, and eradication of the mega-forms. In contrast, the Skeidara displays minimal post-jokulhlaup sediment erosion in its upstream reaches and little change in braided channel relief. This contrast between river systems is attributed to the presence of a previously studied similar to 2-km wide ice-marginal trench, caused by glacier retreat and lowering, which contained flows of the Gigjukvisl but not the Skeidara prior to dispersal onto the outwash plain. Rapid removal of jokulhlaup deposits from this trench suggests that in terms of long-term evolution of the sandur, such features only delay downstream migration of jokulhlaup-derived sediment. These results, therefore, suggest that the net geomorphic impact of jokulhlaups on surface relief of Skeidararsandur, while profound in the short term, may be eradicated within years to decades. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. SUNY Syracuse, Coll Environm Sci & Forestry, Syracuse, NY 13210 USA. Dartmouth Coll, Dept Geog, Hanover, NH 03775 USA. Univ Nebraska, Dept Geosci, Lincoln, NE 68588 USA. Indiana State Univ, Geomorphol Lab, Terre Haute, IN 47809 USA. Univ Calif Santa Barbara, Dept Geog, Santa Barbara, CA 93106 USA. NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Wallops Isl, VA 23337 USA. NASA, Washington, DC 20546 USA. RP Smith, LC (reprint author), Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. EM lmith@geog.ucla.edu RI Smith, Laurence/E-7785-2012; Last, First/A-6350-2013 OI Smith, Laurence/0000-0001-6866-5904; NR 36 TC 18 Z9 18 U1 3 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-555X J9 GEOMORPHOLOGY JI Geomorphology PD APR PY 2006 VL 75 IS 1-2 SI SI BP 65 EP 75 DI 10.1016/j.geomorph.2004.01.012 PG 11 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 037SE UT WOS:000237166500005 ER PT J AU Benjamin, D Wahr, J Ray, RD Egbert, GD Desai, SD AF Benjamin, David Wahr, John Ray, Richard D. Egbert, Gary D. Desai, Shailen D. TI Constraints on mantle anelasticity from geodetic observations, and implications for the J(2) anomaly SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article DE Earth rotation; Earth tides; J(2) anomaly; mantle anelasticity ID LONG-PERIOD TIDES; CHANDLER-WOBBLE; EARTHS ROTATION; OCEAN TIDES; FREQUENCY-DEPENDENCE; TIDAL VARIATIONS; MODEL; LENGTH; EQUILIBRIUM; OBLATENESS AB We use geodetic observations of the Earth to constrain anelasticity in the Earth's mantle at periods between 12 hr and 18.6 yr. The observations include satellite laser ranging (SLR) measurements of 12 hr and 18.6 yr tides in the J(2) component of the gravity field; space-based observations of tidal variations in the Earth's rotation rate; and optical and space-based measurements of the Chandler Wobble period and damping. These geophysical signals are mostly sensitive to the lower mantle. The results suggest the dissipative process could consist of a single absorption band that extends across seismic periods out at least as far as similar to 20 yr. The results also require values of the anelastic parameter Q that are smaller than those required by seismic observations. We interpret this as evidence that Q in the lower mantle is frequency dependent. The frequency dependence suggested by the geodetic observations is reasonably consistent with laboratory measurements, though those measurements have only been done on rocks at upper mantle conditions. After fitting and removing the 18.6 yr tide from the SLR J(2) results, we find that the 1998-2002 anomaly present in the original J(2) observations is no longer a singular anomaly in the J(2) residuals, but becomes one of a series of maxima in a quasi-decadal oscillation. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Space Geodesy Branch, Greenbelt, MD 20771 USA. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Benjamin, D (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. EM wahr@colorado.edu RI Ray, Richard/D-1034-2012; OI Egbert, Gary/0000-0003-1276-8538 NR 38 TC 34 Z9 34 U1 0 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0956-540X EI 1365-246X J9 GEOPHYS J INT JI Geophys. J. Int. PD APR PY 2006 VL 165 IS 1 BP 3 EP 16 DI 10.1111/j.1365-246X.2006.02915.x PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 072RA UT WOS:000239689500002 ER PT J AU Euskirchen, ES McGuire, AD Kicklighter, DW Zhuang, Q Clein, JS Dargaville, RJ Dye, DG Kimball, JS McDonald, KC Melillo, JM Romanovsky, VE Smith, NV AF Euskirchen, ES McGuire, AD Kicklighter, DW Zhuang, Q Clein, JS Dargaville, RJ Dye, DG Kimball, JS McDonald, KC Melillo, JM Romanovsky, VE Smith, NV TI Importance of recent shifts in soil thermal dynamics on growing season length, productivity, and carbon sequestration in terrestrial high-latitude ecosystems SO GLOBAL CHANGE BIOLOGY LA English DT Article DE carbon sequestration; climate change; growing season; permafrost; productivity; respiration; snow cover; terrestrial ecosystem model ID CLIMATE-CHANGE; ATMOSPHERIC CO2; NORTHERN-HEMISPHERE; DECIDUOUS FOREST; ORGANIC-CARBON; BOREAL FORESTS; ARCTIC TUNDRA; UNITED-STATES; SNOW-COVER; MODEL AB In terrestrial high-latitude regions, observations indicate recent changes in snow cover, permafrost, and soil freeze-thaw transitions due to climate change. These modifications may result in temporal shifts in the growing season and the associated rates of terrestrial productivity. Changes in productivity will influence the ability of these ecosystems to sequester atmospheric CO2. We use the terrestrial ecosystem model (TEM), which simulates the soil thermal regime, in addition to terrestrial carbon (C), nitrogen and water dynamics, to explore these issues over the years 1960-2100 in extratropical regions (30-90 degrees N). Our model simulations show decreases in snow cover and permafrost stability from 1960 to 2100. Decreases in snow cover agree well with National Oceanic and Atmospheric Administration satellite observations collected between the years 1972 and 2000, with Pearson rank correlation coefficients between 0.58 and 0.65. Model analyses also indicate a trend towards an earlier thaw date of frozen soils and the onset of the growing season in the spring by approximately 2-4 days from 1988 to 2000. Between 1988 and 2000, satellite records yield a slightly stronger trend in thaw and the onset of the growing season, averaging between 5 and 8 days earlier. In both, the TEM simulations and satellite records, trends in day of freeze in the autumn are weaker, such that overall increases in growing season length are due primarily to earlier thaw. Although regions with the longest snow cover duration displayed the greatest increase in growing season length, these regions maintained smaller increases in productivity and heterotrophic respiration than those regions with shorter duration of snow cover and less of an increase in growing season length. Concurrent with increases in growing season length, we found a reduction in soil C and increases in vegetation C, with greatest losses of soil C occurring in those areas with more vegetation, but simulations also suggest that this trend could reverse in the future. Our results reveal noteworthy changes in snow, permafrost, growing season length, productivity, and net C uptake, indicating that prediction of terrestrial C dynamics from one decade to the next will require that large-scale models adequately take into account the corresponding changes in soil thermal regimes. C1 Univ Alaska Fairbanks, Inst Arctic Biol, Fairbanks, AK 99775 USA. Univ Alaska Fairbanks, US Geol Survey, Alaska Cooperat Fish &Wildlife Res Unit, Fairbanks, AK 99775 USA. Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. Purdue Univ, Dept Earth & Atmospher Sci, W Lafayette, IN 47907 USA. Purdue Univ, Dept Agron, W Lafayette, IN 47907 USA. Univ Paris 06, CLIMPACT, F-75252 Paris 05, France. Japan Agcy Marine Earth Sci & Technol, Frontier Res Ctr Global Change, Yokohama, Kanagawa, Japan. Univ Montana, Flathead Lake Biol Stn, Div Biol Sci, Polson, MT 59860 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91101 USA. Univ Alaska Fairbanks, Inst Geophys, Fairbanks, AK 99775 USA. CALTECH, Pasadena, CA 91125 USA. RP Euskirchen, ES (reprint author), Univ Alaska Fairbanks, Inst Arctic Biol, Fairbanks, AK 99775 USA. EM ffese@uaf.edu RI Zhuang, Qianlai/A-5670-2009; OI Dargaville, Roger/0000-0002-0103-5198 NR 64 TC 165 Z9 171 U1 5 U2 110 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1354-1013 EI 1365-2486 J9 GLOBAL CHANGE BIOL JI Glob. Change Biol. PD APR PY 2006 VL 12 IS 4 BP 731 EP 750 DI 10.1111/j.1365-2486.2006.01113.x PG 20 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 029GT UT WOS:000236549600011 ER PT J AU Hu, LY Yang, S Miller, AK Park, CS Plichta, KA Rochford, SJ Schulz, ME Orwoll, RA AF Hu, LY Yang, S Miller, AK Park, CS Plichta, KA Rochford, SJ Schulz, ME Orwoll, RA TI Aliphatic/aromatic hybrid polymers for functionally graded radiation shielding SO HIGH PERFORMANCE POLYMERS LA English DT Article DE polyimides; poly(arylene ethers); radiation shielding AB High hydrogen-content aliphatic polymers have been identified as good for shielding against galactic cosmic radiation. However, their utility in structural elements is limited to modest temperatures where desirable mechanical properties are maintained. On the other hand, aromatic polymers generally have a broader range of operating temperatures but are less effective as radiation shields. The radiation shielding properties of aromatic polymers is enhanced by the incorporation of hydrogen-rich aliphatic groups appended to aromatic units in the macromolecular structure. It is envisioned that functionally graded polymer structures using aliphatic/aromatic hybrids can be used to meet the requirements of the service environment with beneficial radiation shielding properties in future space structural applications. This paper discusses the syntheses of such hybrid polymers. C1 Coll William & Mary, Dept Chem, Williamsburg, VA 23187 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Orwoll, RA (reprint author), Coll William & Mary, Dept Chem, Williamsburg, VA 23187 USA. EM raorwo@wm.edu NR 11 TC 0 Z9 0 U1 0 U2 3 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0954-0083 J9 HIGH PERFORM POLYM JI High Perform. Polym. PD APR PY 2006 VL 18 IS 2 BP 213 EP 225 DI 10.1177/0954008306059342 PG 13 WC Polymer Science SC Polymer Science GA 032HP UT WOS:000236765800007 ER PT J AU Kossacki, KJ Markiewicz, WJ Smith, MD Page, D Murray, J AF Kossacki, KJ Markiewicz, WJ Smith, MD Page, D Murray, J TI Possible remnants of a frozen mud lake in southern Elysium, Mars SO ICARUS LA English DT Article DE Mars, surface; Mars, climate ID THERMAL EMISSION SPECTROMETER; GROUND ICE; WATER ICE; SURFACE; STABILITY; REGOLITH; MODELS; REGION; LAYER AB In this work we estimate the minimum persistence time of subsurface ice in water rich sediment layers remaining after sublimation of a martian lake. We simulate sublimation of ice from layers of different granulations and thicknesses. Presented results assume insolation and atmospheric conditions characteristic for the present day southern Elysium, where data from Mars Express have identified surface features possibly indicating the very recent presence of a frozen body of water [Murray et al., 2005. Nature 434, 352-356]. The age of these features is estimated to be several million years. On this time scale, we find that most of the water ice must have sublimated away, however remnant ice at a few percent level cannot be excluded. This amount of water ice is sufficient for chemical cementation of the observed features and explains their relatively pristine appearance, without significant signs of erosion. (c) 2005 Elsevier Inc. All rights reserved. C1 Warsaw Univ, Inst Geophys, PL-02093 Warsaw, Poland. Max Planck Inst Solar Syst Res, D-37191 Katlenburg Duhm, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20071 USA. Open Univ, Planetary & Space Sci Res Inst, Milton Keynes MK7 6AA, Bucks, England. Open Univ, Dept Earth Sci, Milton Keynes MK7 6AA, Bucks, England. RP Kossacki, KJ (reprint author), Warsaw Univ, Inst Geophys, Pasteura 7, PL-02093 Warsaw, Poland. EM kjkossac@igf.fuw.edu.pl NR 29 TC 8 Z9 8 U1 1 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2006 VL 181 IS 2 BP 363 EP 374 DI 10.1016/j.icarus.2005.11.018 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032AF UT WOS:000236745600004 ER PT J AU Milkovich, SM Head, JW Marchant, DR AF Milkovich, SM Head, JW Marchant, DR TI Debris-covered piedmont glaciers along the northwest flank of the Olympus Mons scarp: Evidence for low-latitude ice accumulation during the Late Amazonian of Mars SO ICARUS LA English DT Article DE Mars, surface; Mars, climate; Mars, atmosphere ID AUREOLE DEPOSITS; ROCK GLACIERS; SUBLIMATION; LANDSLIDES; ANTARCTICA; GLACIATION; MECHANISMS; MORPHOLOGY; EVOLUTION; OBLIQUITY AB We use Viking and new MGS and Odyssey data to characterize the lobate deposits superimposed on aureole deposits along the west and northwest flanks of Olympus Mons, Mars. These features have previously been interpreted variously as landslide, pyroclastic, lava flow or glacial features on the basis of Viking images. The advent of multiple high-resolution image and topography data sets from recent spacecraft missions allow us to revisit these features and assess their origins. On the basis of these new data, we interpret these features as glacial deposits and the remnants of cold-based debris-covered glaciers that underwent multiple episodes of advance and retreat, occasionally interacting with extrusive volcanism from higher on the slopes of Olympus Mons. We subdivide the deposits into fifteen distinctive lobes. Typical lobes begin at a theater-like alcove in the escarpment at the base of Olympus Mons, interpreted to be former ice-accumulation zones, and extend outward as a tongue-shaped or fan-shaped deposit. The surface of a typical lobe contains (moving Outward from the basal escarpment): a chaotic facies of disorganized hillocks, interpreted as sublimation till in the accumulation zone; arcuate-ridged facies characterized by regular, subparallel ridges and interpreted as the ridges Of Surface debris formed by the flow of underlying ice: and marginal ridges interpreted as local terminal moraines. Several lobes also contain a hummocky facies toward their margins that is interpreted as a distinctive type of sublimation till shaped by structural dislocations and preferential loss of ice. Blocky units are found extending from the escarpment onto several lobes: these units are interpreted as evidence of lava-ice interaction and imply that ice was present at a time of eruptive volcanic activity higher on the slopes of Olympus Mons. Other than minor channel-like features in association with lava-ice interactions, we find no evidence for the flow of liquid water in association with these lobate features that might suggest: (1) near-surface groundwater as a source for ice in the alcoves in the lobe source region at the base of the scarp, or (2) basal melting and drainage emanating from the lobes that might indicate wet-based glacial conditions. Instead, the array of features is consistent with cold-based glacial processes. The glacial interpretations outlined here are consistent with recent geological evidence for low-latitude ice-rich features at similar positions on the Tharsis Montes as well as with orbital dynamic and climate models indicating extensive snow and ice accumulation associated with episodes of increased obliquity during the Late Amazonian period of the history of Mars. (c) 2005 Elsevier Inc. All rights reserved. C1 Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. Boston Univ, Dept Earth Sci, Boston, MA 02215 USA. RP Milkovich, SM (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-501, Pasadena, CA 91109 USA. EM sarah.m.milkovich@jpl.nasa.gov NR 45 TC 49 Z9 49 U1 2 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2006 VL 181 IS 2 BP 388 EP 407 DI 10.1016/j.icarus.2005.12.006 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032AF UT WOS:000236745600006 ER PT J AU Fast, K Kostiuk, T Espenak, F Annen, J Buhl, D Hewagama, T A'Hearn, MF Zipoy, D Livengood, TA Sonnabend, G Schmulling, F AF Fast, K Kostiuk, T Espenak, F Annen, J Buhl, D Hewagama, T A'Hearn, MF Zipoy, D Livengood, TA Sonnabend, G Schmulling, F TI Ozone abundance on Mars from infrared heterodyne spectra I. Acquisition, retrieval, and anticorrelation with water vapor SO ICARUS LA English DT Article DE Mars, atmosphere; infrared observations; photochemistry; spectroscopy; abundances, atmospheres ID ULTRAVIOLET SPECTROMETER EXPERIMENT; MARTIAN ATMOSPHERE; NATURAL LASER; APHELION; EMISSION; DAYGLOW; SPECTROSCOPY; SEASON; LINE; TES AB Observations of ozone on Mars were made using the Goddard Space Flight Center's Infrared Heterodyne Spectrometer and Heterodyne Instrument for Planetary Wind and Composition at the NASA Infrared Telescope Facility. Ozone is an important observable tracer of martian photochemistry. Infrared heterodyne spectroscopy with spectral resolution >= 10(6) is the only technique that directly measures ozone in the martian atmosphere from the surface of the Earth. Ozone column abundances down to the martian surface were acquired in seven data sets taken between 1988 and 2003 at various orbital positions (LS = 40 degrees, 74 degrees, 102 degrees, 115 degrees, 202 degrees, 208 degrees, 291 degrees). Ozone abundances are compared with those retrieved using ultraviolet techniques, showing good agreement. Odd hydrogen (HOX) chemistry predicts anticorrelation of ozone and water vapor abundances. Retrieved ozone abundances consistently show anticorrelation with corresponding water vapor abundances. providing strong confirmation of odd hydrogen activity. Deviation front strict anticorrelation between the observed total column densities of ozone and water vapor suggests that constituent vertical distribution is an additional, significant factor. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Planetary Syst Lab, Natl Res Council Associate, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Univ Space Res Assoc, Washington, DC 20036 USA. Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany. EM kelly.e.fast@nasa.gov RI Hewagama, T/C-8488-2012; Livengood, Timothy/C-8512-2012; Kostiuk, Theodor/A-3077-2014 NR 38 TC 22 Z9 22 U1 0 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2006 VL 181 IS 2 BP 419 EP 431 DI 10.1016/j.icarus.2005.12.001 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032AF UT WOS:000236745600008 ER PT J AU Estrada, PR Mosqueira, I AF Estrada, PR Mosqueira, I TI A gas-poor planetesimal capture model for the formation of giant planet satellite systems SO ICARUS LA English DT Article DE Jovian planets; satellites of Jupiter; satellites of Saturn; planetesimals ID EVOLUTIONARY TURBULENT MODEL; ACCRETION DISKS; COLLISIONAL EVOLUTION; GASEOUS NEBULA; SOLAR NEBULA; GALILEAN SATELLITES; REGULAR SATELLITES; PROTOSTELLAR DISKS; TITANS ATMOSPHERE; MASS PLANETS AB Assuming that an unknown mechanism (e.g., gas turbulence) removes most of the subnebula gas disk in a timescale shorter than that for satellite formation, we develop a model for the formation of regular (and possibly at least some of the irregular) satellites around giant planets in a gas-poor environment. In this model, which follows along the lines of the work of Safronov et al. [1986. Satellites. Univ. of Arizona Press, Tucson, pp. 89-116], heliocentric planetesimals collide within the planet's Hill sphere and generate a circumplanetary disk of prograde and retrograde satellitesimals extending as far out as similar to R-H/2. At first, the net angular momentum of this proto-satellite swarm is small, and collisions among satellitesimals leads to loss of mass front the Outer disk, and delivers mass to the inner disk (where regular satellites form) in a timescale less than or similar to 105 years. This mass loss may be offset by continued collisional capture of sufficiently small < 1 kin interlopers resulting from the disruption of planetesimals in the feeding zone of the giant planet. As the planet's feeding zone is cleared in a timescale; 103 years, enough angular momentum may be delivered to the proto-satellite swarm to account for the angular momentum of the regular satellites of Jupiter and Saturn. This feeding timescale is also roughly consistent with the independent constraint that the Galilean satellites formed in a timescale of 10(5)-10(6) years, which may be long enough to accommodate Callisto's partially differentiated state [Anderson et al., 1998. Science 280, 1573; Anderson et al., 2001. Icarus 153, 157-161]. In turn, this formation timescale can be used to provide plausible constraints on the surface density of solids in the satellitesimal disk (excluding satellite embryos similar to 1 gcm(-2) for satellitesimals of size similar to 1 kin), which yields a total disk mass smaller than the mass of the regular satellites, and means that the satellites must form in several similar to 10 collisional cycles. However, much more work will need to be conducted concerning the collisional evolution both of the circumplanetary satellitesimals and of the heliocentric planetesimals following giant planet formation before one can assess the significance of this agreement. Furthermore, for enough mass to be delivered to form the regular satellites in the required timescale one may need to rely on (unproven) mechanisms to replenish the feeding zone of the giant planet. We compare this model to the solids-enhanced minimum mass (SEMM) model of Mosqueira and Estrada [2003a. Icarus 163, 198-231; 2003b. Icarus 163, 232-255], and discuss its main consequences for Cassini observations of the saturnian satellite system. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94305 USA. NASA, Ames SETI Inst, Moffett Field, CA 94305 USA. RP Estrada, PR (reprint author), NASA, Ames Res Ctr, Mail Stop 245-3, Moffett Field, CA 94305 USA. EM estrada@cosmic.arc.nasa.gov; mosqueir@cosmic.arc.nasa.gov NR 77 TC 21 Z9 21 U1 0 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD APR PY 2006 VL 181 IS 2 BP 486 EP 509 DI 10.1016/j.icarus.2005.11.006 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032AF UT WOS:000236745600014 ER PT J AU Borucki, WJ Whitten, RC Bakes, ELO Barth, E Tripathi, SN AF Borucki, WJ Whitten, RC Bakes, ELO Barth, E Tripathi, SN TI Predictions of the electrical conductivity and charging of the aerosols in Titan's atmosphere SO ICARUS LA English DT Article DE titan; ionospheres; radiation chemistry; photochemistry ID POLYCYCLIC AROMATIC-HYDROCARBONS; COSMIC-RAY IONIZATION; VERTICAL-DISTRIBUTION; LOWER IONOSPHERE; PARTICLES; IONS; CHEMISTRY; RECOMBINATION; MAGNETOSPHERE; SCATTERING AB The electrical conductivity and electrical charge on the aerosols in atmosphere of Titan are computed for altitudes between 0 and 400 km. Ionization of methane and nitrogen due to galactic cosmic rays (GCR) is important at night where these ions are converted to ion Clusters such as CH5+CH4, C7H7+, C4H7+, and H4C7N+. The ubiquitous aerosols observed also play -,in important role in determining the charge distribution in the atmosphere. Because polycyclic aromatic hydrocarbons (PAHs) are expected in Titan's atmosphere and have been observed in the laboratory and found to be electrophilic, we consider the formation of negative ions. During the night, the very smallest molecular complexes accept free electrons to form negative ions. This results in a large reduction of the electron abundance both in the region between 150 and 350 km over that predicted when such aerosols are not considered. During the day time, ionization by photoemission from aerosols irradiated by solar ultraviolet (UV) radiation overwhelms the GCR-produced ionization. The presence of hydrocarbon and nitrile minor constituents substantially reduces the UV flux in the wavelength band from the cutoff of CH4 at 155 to 200 nm. These aerosols have such a low ionization potential that the bulk of the solar radiation at longer wavelengths is energetic enough to produce a photoionization rate Sufficient to create an ionosphere even without galactic cosmic ray (GCR) bombardment. At altitudes below 60 km, the electron and positive ion abundances are influenced by the three-body recombination of ions and electrons. The addition of this reaction significantly reduces the predicted electron abundance over that previously predicted. Our calculations for the dayside show that the peaks of the charge distributions move to larger values as the altitude increases. This variation is the result of the increased UV flux present at the highest altitudes. Clearly, the situation is quite different than that for the night where the peak of the distribution for a particular size is nearly constant with altitude when negative ions are not present. The presence of very small aerosol particles (embryos) may cause the peak of the distribution to decrease from about 8 negative charges to as little as one negative charge or even zero charge. This dependence on altitude will require models of the aerosol formation to change their algorithms to better represent the effect of charged aerosols as a function of altitude. In particular, the charge state will be much higher than previously predicted and it will not be constant with altitude during the day time. Charging of aerosol particles, whether on the dayside or nightside, has a major influence on both the electron abundance and electrical conductivity. The predicted conductivities are within the measurement range of the HASI PWA instrument over most but not all, of the altitude range sampled. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. SETI Inst, Mountain View, CA 94043 USA. SW Res Inst, San Antonio, TX 78228 USA. Indian Inst Technol, Kanpur 208016, Uttar Pradesh, India. RP Borucki, WJ (reprint author), NASA, Ames Res Ctr, MS 244-30, Moffett Field, CA 94035 USA. EM william.j.borucki@nasa.gov RI Tripathi, Sachchida/J-4840-2016 NR 59 TC 41 Z9 41 U1 0 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD APR PY 2006 VL 181 IS 2 BP 527 EP 544 DI 10.1016/j.icarus.2005.10.030 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 032AF UT WOS:000236745600016 ER PT J AU Evans, DL AF Evans, DL TI Spaceborne imaging radar-C/X-band synthetic aperture radar (SIR-C/X-SAR): a look back on the tenth anniversary SO IEE PROCEEDINGS-RADAR SONAR AND NAVIGATION LA English DT Article; Proceedings Paper CT 6th European Conference on Synthetic Aperture Radar CY MAY 16-18, 2006 CL Dresden, GERMANY ID LAND-COVER CLASSIFICATION; C RADAR; POLARIMETRIC SAR; SOIL-MOISTURE; AMAZON FLOODPLAIN; KILAUEA VOLCANO; NORTHERN FOREST; DATA QUALITY; LAVA FLOWS; INTERFEROMETRY AB The spaceborne imaging radar-C, X-band synthetic aperture radar (SIR-C/X-SAR) missions have resulted in important scientific discoveries and provided new insights into Earth system processes. Analyses of SIR-C/X-SAR engineering-mode data have also led to new measurement and mission concepts. The multifrequency, multipolarisation capability provided by SIR-C/X-SAR is unsurpassed from a spaceborne system, making the data set valuable for algorithm development and assessment of optimal imaging parameters more than a decade after the missions were flown. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Evans, DL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Diane.L.Evans@jpl.nasa.gov NR 81 TC 2 Z9 2 U1 0 U2 4 PU INSTITUTION ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2395 J9 IEE P-RADAR SON NAV JI IEE Proc.-Radar Sonar Navig. PD APR PY 2006 VL 153 IS 2 BP 81 EP 85 DI 10.1049/ip-rsn:20045095 PG 5 WC Telecommunications SC Telecommunications GA 041LJ UT WOS:000237457400002 ER PT J AU Ngo, Q Cassell, AM Austin, AJ Li, J Krishnan, S Meyyappan, M Yang, CY AF Ngo, Q Cassell, AM Austin, AJ Li, J Krishnan, S Meyyappan, M Yang, CY TI Characteristics of aligned carbon nanofibers for interconnect via applications SO IEEE ELECTRON DEVICE LETTERS LA English DT Article DE carbon nanofiber (CNF); interconnect; via ID NANOTUBE; TRANSPORT; RESISTIVITY; GRAPHITE AB Electrical properties of plasma-enhanced chemical vapor deposited carbon nanofibers (CNFs) are characterized with measurements over a broad temperature range (4-300 K). Temperature-dependent measurements of CNF via resistivity reveal a behavior resembling the mixture of graphite alpha-axis and c-axis transport mechanisms. For the first time, temperature-dependent characteristics of CNFs are measured and modeled based on previously developed models for electron conduction in graphite. Reliability measurements are performed to demonstrate the robust electrical and thermal properties of CNF vias for next-generation on-chip-interconnect designs. C1 Santa Clara Univ, Ctr Nanostruct, Santa Clara, CA 95050 USA. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 95050 USA. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Ngo, Q (reprint author), Santa Clara Univ, Ctr Nanostruct, Santa Clara, CA 95050 USA. EM jli@mail.arc.nasa.gov RI Li, Jun/H-7771-2013 OI Li, Jun/0000-0002-3689-8946 NR 26 TC 48 Z9 48 U1 0 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0741-3106 J9 IEEE ELECTR DEVICE L JI IEEE Electron Device Lett. PD APR PY 2006 VL 27 IS 4 BP 221 EP 224 DI 10.1109/LED.2006.870865 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA 028WL UT WOS:000236519400006 ER PT J AU Wang, LL Qu, JJ Xiong, XX Hao, XJ Xie, Y Che, NZ AF Wang, LL Qu, JJ Xiong, XX Hao, XJ Xie, Y Che, NZ TI A new method for retrieving band 6 of Aqua MODIS SO IEEE GEOSCIENCE AND REMOTE SENSING LETTERS LA English DT Article DE Aqua; band 6; Moderate Resolution Imaging Spectroradiometer (MODIS); normalized difference snow index (NDSI); retrieval; Terra AB The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key research instrument for the NASA Earth Observing System (EOS) mission. It was successfully launched onboard the Terra satellite in December 1999 and Aqua satellite in May 2002. Both MODIS instruments have been working well except that 15 of the 20 detectors in Aqua MODIS band 6 (1.628-1.652 mu m) are either nonfunctional or noisy. The striping in Aqua MODIS band 6 caused by its nonfunctional or noisy detectors has been a serious problem for MODIS snow products, which use band 6 primarily for snow detection. MODIS scientists have been using Aqua MODIS band 7 (2.105-2.155 mu m) instead of band 6 for computing the normalized difference snow index to continue detecting global snow coverage. The main objective of this letter is to retrieve Aqua MODIS band 6 using other bands based on their relationships in Terra MODIS. The band retrieval approach proposed in this letter is also very useful for the next generation of MODIS sensor-the Visible/Infrared Imager/Radiometer Suite (VIIRS) band M10 proxy data generation. Such proxy data can support the VIIRS prelaunch end-to-end testing, postlaunch calibration/validation, and data quality checking. C1 George Mason Univ, Fairfax, VA 22030 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Wang, LL (reprint author), George Mason Univ, Fairfax, VA 22030 USA. EM lwang2@gmu.edu RI Hao, Xianjun/F-7253-2016; Hao, Xianjun/C-9543-2011 OI Hao, Xianjun/0000-0002-8186-6839; Hao, Xianjun/0000-0002-8186-6839 NR 11 TC 34 Z9 34 U1 0 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1545-598X J9 IEEE GEOSCI REMOTE S JI IEEE Geosci. Remote Sens. Lett. PD APR PY 2006 VL 3 IS 2 BP 267 EP 270 DI 10.1109/LGRS.2006.869966 PG 4 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 038HO UT WOS:000237210200018 ER PT J AU Perhinschi, MG Napolitano, MR Campa, G Seanor, B Burken, J Larson, R AF Perhinschi, Mario G. Napolitano, Marcello R. Campa, Giampiero Seanor, Brad Burken, John Larson, Richard TI Design of safety monitor schemes for a fault tolerant flight control system SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB For a research aircraft, "conventional" control laws (CLs) are implemented on a "baseline" flight computer (FC) while research CLs are typically housed on a dedicated research computer. Therefore, for an experimental aircraft used to test specific fault tolerant flight control systems, a safety logic scheme is needed to ensure a safe transition from conventional to research CLs (while at nominal conditions) as well as from research CLs at nominal conditions to conditions with "simulated" failures on specific control surfaces. This paper describes the design of such a safety scheme for the NASA Intelligent Flight Control System (IFCS) F-15 Program. The goals of the IFCS F-15 program are to investigate the performance of a set of fault tolerant CLs based on the use of dynamic inversion with neural augmentation. The different transitions are monitored using information relative to flight conditions and controller-related performance criteria. The testing of the scheme is performed with a Simulink-based flight simulation code and interface developed at West Virginia University for the NASA IFCS F-15 aircraft. C1 W Virginia Univ, Dept Mech & Aerosp Engn, Morgantown, WV 26505 USA. NASA, Dryden Flight Res Ctr, Edwards AFB, CA 93523 USA. RP Perhinschi, MG (reprint author), W Virginia Univ, Dept Mech & Aerosp Engn, ESB521, Morgantown, WV 26505 USA. NR 15 TC 5 Z9 5 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 2006 VL 42 IS 2 BP 562 EP 571 DI 10.1109/TAES.2006.1642572 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 065UN UT WOS:000239185400014 ER PT J AU Simon, M Divsalar, D AF Simon, M Divsalar, D TI Some interesting observations for certain line codes with application to RFID SO IEEE TRANSACTIONS ON COMMUNICATIONS LA English DT Article DE line codes; radio frequency identification (RFID) AB In this letter, we bring to the reader's attention some interesting properties of certain line codes that appear to not have been mentioned in the literature, that, in some cases, can be used to enhance their performance when used for digital communication with particular application to radio frequency identification. In addition, we correct a previously reported result pertaining to the performance of such codes. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Simon, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM marvin.k.simon@jpl.nasa.gov; dariush.divsalar@jpl.nasa.gov NR 5 TC 20 Z9 21 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0090-6778 J9 IEEE T COMMUN JI IEEE Trans. Commun. PD APR PY 2006 VL 54 IS 4 BP 583 EP 586 DI 10.1109/TCOMM.2006.873063 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 037AJ UT WOS:000237118800002 ER PT J AU Akarvardar, K Dufrene, BM Cristoloveanu, S Gentil, P Blalock, BJ Mojarradi, MM AF Akarvardar, K Dufrene, BM Cristoloveanu, S Gentil, P Blalock, BJ Mojarradi, MM TI Low-frequency noise in SOI four-gate transistors SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE junction field-effect transistor (JFET); low-frequency noise; MOSFET; multiple-gate transistor; silicon-on-insulator (SOI) ID TELEGRAPH SIGNAL CURRENTS; FIELD-EFFECT TRANSISTORS; MOS-TRANSISTORS; EXCESS NOISE; MODEL; SPECTROSCOPY; DEVICES AB Low-frequency noise characteristics of the siliconon-insulator four-gate transistor [G(4)-field-effect transistor] are reported. The noise power spectral density as a function of biasing conditions is presented and compared for surface and volume conduction modes. It is shown that, for the same drain current, the volume of the transistor generates less noise than its surface. The possible transition from carrier-number fluctuations to mobility fluctuations as the conducting channel is moved away from the surface toward the volume is also discussed. C1 ENSERG, IMEP, F-38016 Grenoble 1, France. IBM Corp, Essex Jct, VT 05452 USA. Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. CALTECH, Jet Prop Lab, Power & Sensor Syst Sect, Pasadena, CA 91109 USA. RP Akarvardar, K (reprint author), ENSERG, IMEP, F-38016 Grenoble 1, France. EM akarvard@enserg.fr NR 22 TC 30 Z9 30 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD APR PY 2006 VL 53 IS 4 BP 829 EP 835 DI 10.1109/TED.2006.870272 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 028FX UT WOS:000236473500034 ER PT J AU Pinheiro, ACT Privette, JL Guillevic, P AF Pinheiro, ACT Privette, JL Guillevic, P TI Modeling the observed angular anisotropy of land surface temperature in a savanna SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE African savanna; angular effects; geometric optics (GO); land surface temperature (LST); thermal infrared (TIR); vegetation structure ID INITIATIVE SAFARI 2000; VEGETATION CANOPY; BIDIRECTIONAL REFLECTANCE; RADIATIVE-TRANSFER; PLANT CANOPIES; AFRICA AB Several recent studies have found that retrievals of land surface temperature (LST) from remote sensing measurements depend upon the angle of observation. To understand, predict, and ultimately correct this sensitivity, simple but physically based models of LST angular anisotropy are needed. In this study, we describe and evaluate the modified geometric projection (MGP) model, a highly parameterized model of scene thermal infrared (TIR) radiance applicable to both homogeneous and discontinuous canopy environments. Based on geometric optics modeling, NIPG assumes that the angular anisotropy of TIR radiance over discontinuous canopies is due strictly to the different proportions of scene endmembers (e.g., sunlit tree crowns, background shadows) visible to a sensor at different sun-view geometries. We tested MGP against DART, a rigorous three-dimensional radiative transfer model, and against field-measured data front a southern Africa savanna. For a prescribed set of canopy conditions, MGPs estimates of observable endmember fractions and scene temperatures in the solar principal plane compared well with estimates front DART. We also parameterized MGP with field-measured endmember data for an acacia/combretum savanna near Skukuza, South Africa. We angularly integrated the MGP-predicted radiances and compared the results with measurements of scene hemispherical exitance front a tower-based pyrgeometer. The modeled exitances exhibited the normal diurnal behavior. Model predictions generally agreed with the pyrgeometer measurements; however, model accuracy decreased as the difference in endmember temperatures increased. These tests suggest that the assumptions inherent in the MGP model do not seriously impact the accuracy of the simulated radiances. We conclude that the MGP model accurately captures the predominate thermal emission directionality resulting front discontinuous canopy structure, and could therefore be applied at continental and global scales. C1 NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. Lab Cent Ponts & Chaussees, Div Eau, F-44341 Bouguenais, France. RP NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Code 661, Greenbelt, MD 20771 USA. EM Ana.Pinheiro@gsfc.nasa.gov RI Privette, Jeffrey/G-7807-2011 OI Privette, Jeffrey/0000-0001-8267-9894 NR 25 TC 25 Z9 26 U1 4 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 EI 1558-0644 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD APR PY 2006 VL 44 IS 4 BP 1036 EP 1047 DI 10.1109/TGRS.2005.863827 PG 12 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 028GD UT WOS:000236474100028 ER PT J AU Villanueva, GL Hartogh, P Reindl, LM AF Villanueva, GL Hartogh, P Reindl, LM TI A digital dispersive matching network for SAW devices in chirp transform spectrometers SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE chirp transform spectrometer (CTS); digital direct synthesis; dispersive delay lines; dispersive matching network; frequency multiplication; microwave heterodyne spectroscopy; surface acoustic wave (SAW) filters ID WATER-VAPOR; DESIGN; CLO; HCL AB The performance of a chirp transform spectrometer can be significantly improved through a digital dispersive matching network. In this paper, we present the development of a new design, the adaptive digital chirp processor (ADCP), which generates an expander chirp signal With dispersive characteristics matching those of the surface acoustic wave filter behaving as a compressor/convolver. This matching signal (i.e., the chirp) is generated by a digital direct synthesizer and is then bandpass filtered, level regulated, up-converted, and frequency tripled in order to achieve the required bandwidth of 430 MHz. The design of the matching network and the signal processing of the resulting dispersive signal demanded a rational and optimum combination of different technologies, such as quadrature modulation, high-performance spectral filtering, ultra-stable frequency sources, and a theoretical analysis of the circuit design by using a numerical model of the ADCP. C1 Max Planck Inst Solar Syst Res, Dept Planetary Sci, D-37191 Katlenburg Lindau, Germany. Inst Microsyst Technol, Dept Elect Measurement Technol, D-79110 Freiburg, Germany. RP NASA, Goddard Space Flight Ctr, Dept Extraterrestrial Phys, Code 661, Greenbelt, MD 20771 USA. EM villanueva@ssedmail.gsfc.nasa.gov; hartogh@mps.mpg.de; reindl@imtek.de NR 34 TC 11 Z9 12 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9480 EI 1557-9670 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD APR PY 2006 VL 54 IS 4 BP 1415 EP 1424 DI 10.1109/TMTT.2006.871244 PN 1 PG 10 WC Engineering, Electrical & Electronic SC Engineering GA 033YC UT WOS:000236889900014 ER PT J AU Aldridge, BM Bowen, L Smith, BR Antonelis, GA Gulland, F Stott, JL AF Aldridge, BM Bowen, L Smith, BR Antonelis, GA Gulland, F Stott, JL TI Paucity of class I MHC gene heterogeneity between individuals in the endangered Hawaiian monk seal population SO IMMUNOGENETICS LA English DT Article DE major histocompatibility complex; Hawaiian monk seal; endangered species; immunogenetics; immunology ID MAJOR HISTOCOMPATIBILITY COMPLEX; GRADIENT GEL-ELECTROPHORESIS; LION ZALOPHUS-CALIFORNIANUS; MOLECULAR CHARACTERIZATION; MASS MORTALITY; SELECTION; POLYMORPHISM; VARIABILITY; DIVERSITY; MONACHUS AB The Hawaiian monk seal population has experienced precipitous declines in the last 50 years. In this study, we provide evidence that individuals from remaining endangered population exhibit alarming uniformity in class I major histocompatibility (MHC) genes. The peripheral blood leukocyte-derived mRNA of six captive animals rescued from a stranding incident on the French frigate shoals in the Hawaiian archipelago was used to characterize genes in the monk seal class I MHC gene family, from which techniques for genotyping the broader population were designed using degenerate primers designed for the three major established human MHC class I loci (HLA-A, HLA-B, and HLA-C), and by sequencing multiple clones, six unique full-length classical MHC class I gene transcripts were identified among the six animals, three of which were only found in single individuals. Since The low degree of sequence variation between these transcripts and the similarity of genotype between individuals provided preliminary evidence for low class I MHC variability in the population. The sequence information from the class I transcripts from these six animals was used to design several primer sets for examining the extent of MHC variability in the remaining population using a combination of polymerase chain reaction and denaturing gradient gel electrophoresis (DGGE). Several DGGE assays, each one amplifying subtly different class I MHC gene combinations, were designed to compare exons encoding the highly polymorphic domains of the putative peptide-binding region of MHC class I. In combination, these assays failed to show interindividual variability at any of the class I MHC gene loci examined in either the six captive seals or in 80 free-ranging animals (similar to 6.7% of the estimated population) representing all six major subpopulations of Hawaiian monk seal. C1 Univ London Royal Vet Coll, N Mymms AL97TA, Herts, England. Univ Calif Davis, Sch Vet Med, Dept Pathol Microbiol & Immunol, Lab Marine Mammal Immunol, Davis, CA 95616 USA. GGNRA, Marine Mammal Ctr TMMC, Sausalito, CA USA. Natl Marine Fisheries Serv, Honolulu, HI USA. RP Aldridge, BM (reprint author), Univ London Royal Vet Coll, Hawkshead Lane, N Mymms AL97TA, Herts, England. EM baldridge@rvc.ac.uk NR 37 TC 13 Z9 13 U1 2 U2 11 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0093-7711 J9 IMMUNOGENETICS JI Immunogenetics PD APR PY 2006 VL 58 IS 2-3 BP 203 EP 215 DI 10.1007/s00251-005-0069-y PG 13 WC Genetics & Heredity; Immunology SC Genetics & Heredity; Immunology GA 028PQ UT WOS:000236500700013 PM 16528500 ER PT J AU Reid, IN Sparks, WB Lubow, S McGrath, M Livio, M Valenti, J Sowers, KR Shukla, HD MacAuley, S Miller, T Suvanasuthi, R Belas, R Colman, A Robb, FT DasSarma, P Muller, JA Coker, JA Cavicchioli, R Chen, F DasSarma, S AF Reid, I. N. Sparks, W. B. Lubow, S. McGrath, M. Livio, M. Valenti, J. Sowers, K. R. Shukla, H. D. MacAuley, S. Miller, T. Suvanasuthi, R. Belas, R. Colman, A. Robb, F. T. DasSarma, P. Mueller, J. A. Coker, J. A. Cavicchioli, R. Chen, F. DasSarma, S. TI Terrestrial models for extraterrestrial life: methanogens and halophiles at Martian temperatures SO INTERNATIONAL JOURNAL OF ASTROBIOLOGY LA English DT Article DE Astrobiology; Archaea; biofilm; extrasolar planets; Mars; psychrophiles AB Cold environments are common throughout the Galaxy. We are conducting a series of experiments designed to probe the low-temperature limits for growth in selected methanogenic and halophilic Archaea. This paper presents initial results for two mesophiles, a methanogen, Methanosarcina acetivorans, and a halophile, Halobacterium sp. NRC-1, and for two Antarctic cold-adapted Archaea, a methanogen, Methanococcoides burtonii, and a halophile, Halorubrum lacusprofundi. Neither mesophile is active at temperatures below 5 degrees C, but both cold-adapted microorganisms show significant growth at sub-zero temperatures (-2 degrees C and -1 degrees C, respectively), extending previous low-temperature limits for both species by 4-5 degrees C. At low temperatures, both H. lacusprofundi and M. burtonii form multicellular aggregates, which appear to be embedded in extracellular polymeric substances. This is the first detection of this phenomenon in Antarctic species of Archaea at cold temperatures. The low-temperature limits for both psychrophilic species fall within the temperature range experienced on present-day Mars and could permit survival and growth, particularly in subsurface environments. We also discuss the results of our experiments in the context of known exoplanet systems, several of which include planets that intersect the Habitable Zone. In most cases, those planets follow orbits with significant eccentricity, leading to substantial temperature excursions. However, a handful of the known gas giant exoplanets could potentially harbour habitable terrestrial moons. C1 [Reid, I. N.; Sparks, W. B.; Lubow, S.; McGrath, M.; Livio, M.; Valenti, J.] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [McGrath, M.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Sowers, K. R.; Shukla, H. D.; MacAuley, S.; Miller, T.; Suvanasuthi, R.; Belas, R.; Colman, A.; Robb, F. T.; DasSarma, P.; Mueller, J. A.; Coker, J. A.; Chen, F.; DasSarma, S.] Univ Maryland, Ctr Marine Biotechnol, Inst Biotechnol, Baltimore, MD 21202 USA. [Mueller, J. A.] Morgan State Univ, Dept Biol, Baltimore, MD 21215 USA. [Cavicchioli, R.] Univ New S Wales, Sch Biotechnol & Biomol Sci, Sydney, NSW 2052, Australia. EM inr@stsci.edu; dassarma@umbi.umd.edu; dassarma@umbi.umd.edu RI Cavicchioli, Ricardo/D-4341-2013; Chen, Feng/P-3088-2014; OI Cavicchioli, Ricardo/0000-0001-8989-6402; Coker, James/0000-0002-1935-5413; Robb, Frank/0000-0001-5833-6496 FU Space Telescope Science Institute's Director's Discretionary Research Fund, NSF grant [MCB-0110762]; NSF grant [MCB-0135595]; Australian Research Council FX We thank Tim Maugel and the University of Maryland Laboratory for Biological Ultrastructure for guidance with the SEM sample preparation and imaging. This work was supported through a grant from the Space Telescope Science Institute's Director's Discretionary Research Fund, NSF grant MCB-0110762 to KRS, and NSF grant MCB-0135595 to SD. The laboratory of RC is supported by funding from the Australian Research Council. NR 57 TC 28 Z9 29 U1 1 U2 17 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 1473-5504 J9 INT J ASTROBIOL JI Int. J. Astrobiol. PD APR PY 2006 VL 5 IS 2 BP 89 EP 97 DI 10.1017/S1473550406002916 PG 9 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA V28BM UT WOS:000208656300001 ER PT J AU Wang, HL Lau, KM AF Wang, HL Lau, KM TI Atmospheric hydrological cycle in the tropics in twentieth century coupled climate simulations SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE tropical hydrological cycle; temperature; precipitation; clouds; radiative flux ID GENERAL-CIRCULATION; PRECIPITATION; TEMPERATURE; MODEL; VARIABILITY; SENSITIVITY; INTENSITY; TRENDS; OCEANS; LAND AB The objective of this study is to identify and understand the long-term change of the tropical hydrological cycle in twentieth-century climate simulations provided by 16 Coupled General Circulation Models (CGCMs) participating in the Intergovernmental Panel on Climate Change (IPCC), Fourth Assessment Report (AR4). This work is focused on trends of precipitation and clouds over the tropical ocean and land. We find that the CGCMs are reasonably consistent in depicting aspects of long-term changes in twentieth century climate and the tropical hydrological cycle, including (1) a relatively good simulation of trends in surface warming over both the tropical ocean and land, in agreement with observations; (2) increasing precipitation over the tropical ocean and decreasing precipitation over tropical land; (3) an increasing trend in heavy and light rain, but a decreasing trend in moderate rain, over the tropical ocean; and (4) a reduction in total cloud cover in the tropics. These successful simulations are encouraging and enhance Our confidence in the future climate projections provided by these models. On the other hand, the current generation of CGCMs still has a number of deficiencies, particularly in modeling clouds and their interactions with radiation. Although most CGCMs are able to simulate the correct sign of trends in precipitation and clouds, they significantly underestimate the magnitudes of the observations. These underestimations likely cause gross errors in model simulations of the global water and energy balance. A better understanding of physical processes and an improvement in the CGCM representations of physical processes associated with Clouds and their interaction with radiation are needed. Copyright (C) 2005 Royal Meteorological Society. C1 NASA, Goddard Space Flight Ctr, Climate & Radiat Branch UMBC GEST, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP Wang, HL (reprint author), NASA, Goddard Space Flight Ctr, Climate & Radiat Branch UMBC GEST, Atmospheres Lab, Code 613-2, Greenbelt, MD 20771 USA. EM hwang@climate.gsfc.nasa.gov RI Lau, William /E-1510-2012 OI Lau, William /0000-0002-3587-3691 NR 41 TC 8 Z9 11 U1 0 U2 6 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0899-8418 J9 INT J CLIMATOL JI Int. J. Climatol. PD APR PY 2006 VL 26 IS 5 BP 655 EP 678 DI 10.1002/joc.1279 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040HW UT WOS:000237370600007 ER PT J AU Siegel, PH Dengler, RJ AF Siegel, Peter H. Dengler, Robert J. TI Terahertz heterodyne imaging Part I: Introduction and techniques SO INTERNATIONAL JOURNAL OF INFRARED AND MILLIMETER WAVES LA English DT Article ID INFRARED DETECTION; MICROBOLOMETERS; BOLOMETERS; TECHNOLOGY; DETECTORS AB The authors present their ongoing work on terahertz heterodyne imaging techniques derived from space science applications and components. In Part I, introductory information and general techniques are provided. Part II contains descriptions of four different heterodyne imaging instruments that have been established at the authors' facilities. In Part III selected applications are discussed. Parts II and III will appear in subsequent issues of this journal. C1 CALTECH, Div Biol, Beckman Inst, Pasadena, CA 91125 USA. Jet Prop Lab, Submillimeter Wave Adv Technol, Pasadena, CA 91109 USA. RP Siegel, PH (reprint author), CALTECH, Div Biol, Beckman Inst, 1200 E Calif Blvd, Pasadena, CA 91125 USA. EM phs@caltech.edu NR 49 TC 30 Z9 32 U1 1 U2 11 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0195-9271 J9 INT J INFRARED MILLI JI Int. J. Infrared Millimeter Waves PD APR PY 2006 VL 27 IS 4 BP 465 EP 480 DI 10.1007/s10762-006-9103-x PG 16 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 074DE UT WOS:000239792100001 ER PT J AU Ponomarev, AL Cucinotta, FA AF Ponomarev, AL Cucinotta, FA TI Chromatin loops are responsible for higher counts of small DNA fragments induced by high-LET radiation, while chromosomal domains do not affect the fragment sizes SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article DE DSB; DNA fragment; DNA organization; chromosomal domain; chromatin loop; high-LET ion ID DOUBLE-STRAND BREAKS; FIELD GEL-ELECTROPHORESIS; INTERPHASE CHROMOSOMES; PARTICLE IRRADIATION; LIGHT-IONS; MODEL; CELLS; DAMAGE; SIMULATION AB Purpose: To apply a polymer model of DNA damage induced by high-LET (linear energy transfer) radiation and determine the influence of chromosomal domains and loops on fragment length distribution. Materials and methods: The yields of DSB (double-strand breaks) induced by high-LET radiation were calculated using a track structure model along with a polymer model of DNA packed in the cell nucleus. The cell nucleus was constructed to include the chromosomal domains and chromatin loops. The latter were generated by the random walk method. Results and conclusions: We present data for DSB yields per track per cell, DNA fragment sizes, the radial distribution of DSB with respect to the track center, and the distribution of 0, 1, 2, and more DSB from a single particle. Calculations were carried out for a range of particles including He (40 keV/mu m), N (225 keV/mu m), and Fe ions (150 keV/mu m). Situations relevant to PFGE (pulsed-field gel electrophoresis) and microbeam experiments with direct irradiation of the cell nucleus were simulated to demonstrate the applicability of the model. Data show that chromosomal domains do not have a significant influence on fragment-size distribution, while the presence of DNA loops increases the frequencies of smaller fragments by nearly 30% for fragment sizes in the range from 2 kbp (bp = base pair) to 20 kbp. C1 NASA, Lyndon B Johnson Space Ctr, JSC, SK Human Adaptat & Countermeasures, Houston, TX 77058 USA. USRA, Houston, TX USA. RP Ponomarev, AL (reprint author), NASA, Lyndon B Johnson Space Ctr, JSC, SK Human Adaptat & Countermeasures, SK-221,Build 37,119,2101 NASA Pkwy, Houston, TX 77058 USA. EM aponomar@ems.jsc.nasa.gov NR 32 TC 22 Z9 22 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD APR PY 2006 VL 82 IS 4 BP 293 EP 305 DI 10.1080/09553000600637716 PG 13 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 041QL UT WOS:000237470700008 PM 16690597 ER PT J AU Meagher, JP Haddad, ZS AF Meagher, JP Haddad, ZS TI To what extent can raindrop size be determined by a multiple-frequency radar? SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article ID NUMERICAL SIMULATIONS AB In this paper, an analytical treatment of the atmospheric remote sensing problem of determining the raindrop size distribution (DSD) with a spaceborne multifrequency microwave nadir-looking radar system is presented. It is typically assumed that with two radar measurements at different frequencies one ought to be able to calculate two state variables of the DSD: a bulk quantity, such as the rain rate, and a distribution shape parameter. To determine if this nonlinear problem can indeed be solved, the DSD is modeled as a h distribution and quadratic approximations to the corresponding radar-rain relations are used to examine the invertibility of the resulting system of equations in the case of two as well as three radar frequencies. From the investigation, it is found that for regions of DSD state space multiple solutions exist for two or even three different frequency radar measurements. This should not be surprising given the nonlinear coupled nature of the problem. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Meagher, JP (reprint author), CALTECH, Jet Prop Lab, 300-243,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM meagher@jpl.nasa.gov NR 14 TC 4 Z9 4 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1558-8424 J9 J APPL METEOROL CLIM JI J. Appl. Meteorol. Climatol. PD APR PY 2006 VL 45 IS 4 BP 529 EP 536 DI 10.1175/JAM2344.1 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040YT UT WOS:000237420300001 ER PT J AU Kim, CSS Kiris, C Kwak, D David, T AF Kim, CSS Kiris, C Kwak, D David, T TI Numerical simulation of local blood flow in the carotid and cerebral arteries under altered gravity SO JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID NON-NEWTONIAN PROPERTIES; BIFURCATION MODEL; STEADY; HUMANS AB A computational fluid dynamics (CFD) approach was presented to model the blood flows in the carotid bifurcation and the brain arteries tinder altered gravity. Physical models required for CFD simulation were introduced including a model for arterial wall motion due to fluid-wall interactions, a shear thinning fluid model of blood, a vascular bed model for outflow boundary conditions, and a model for autoregulation mechanism. The three-dimensional unsteady incompressible Navier-Stokes equations coupled with these models were solved iteratively using the pseudocompressibility method and dual time stepping. Gravity source terms were added to the Navier-Stokes equations to take the effect of gravity into account. For the treatment of complex geometry a chimera overset grid technique was adopted to obtain connectivity between arterial branches. For code validation, computed results were compared with experimental data for both steady-state and time-dependent flows. This computational approach was then applied to blood flows through a realistic carotid bifurcation and two Circle of Willis models, one using an idealized geometry and the other using an anatomical data set. A three-dimensional Circle of Willis configuration was reconstructed from subject-specific magnetic resonance images using at? image segmentation method. Through the numerical simulation of blood flow in two model problems, namely, the carotid bifurcation and the brain arteries, it was observed that the altered gravity has considerable effects on arterial contraction/ dilatation and consequent changes in flow conditions. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Canterbury, Dept Mech Engn, Christchurch 8020, New Zealand. RP NASA, Ames Res Ctr, M-S T27B-1, Moffett Field, CA 94035 USA. EM ckiris@mail.arc.nasa.gov NR 24 TC 25 Z9 27 U1 1 U2 5 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0148-0731 EI 1528-8951 J9 J BIOMECH ENG-T ASME JI J. Biomech. Eng.-Trans. ASME PD APR PY 2006 VL 128 IS 2 BP 194 EP 202 DI 10.1115/1.2165691 PG 9 WC Biophysics; Engineering, Biomedical SC Biophysics; Engineering GA 027ZV UT WOS:000236455800004 PM 16524330 ER PT J AU Copland, E AF Copland, E TI Vapor pressures in the {Al(l)+Al2O3(S)} system: Reconsidering Al2O3(S) condensation SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article DE Al(g) and Al2O(g) vaporization; Al2O3(S) condensation; improving thermodynamic measurements; multiple effusion cell mass spectrometry ID TEMPERATURE MASS-SPECTROMETRY; EFFUSION METHOD; CELL METHOD; CONSTRAINTS; AL-AL2O3 AB The vaporization behavior of the Al-O system has been studied on numerous occasions but significant uncertainties remain. The origin of this uncertainty must be understood before Al-O vaporization behavior can be accurately determined. The condensation of Al2O3 and clogging of the effusion orifice is a difficult problem for the Knudsen effusion technique that influences the measured vaporization behavior but has only received limited attention. This study reconsiders this behavior in detail. A new theory for Al2O3 condensation is proposed together with procedures that will improve the measured thermodynamic properties of Al-O vaporization. (C) 2005 Elsevier Ltd. All rights reserved. C1 Case Western Reserve Univ, Dept Mat Sci & Engn, NASA Glenn Res Ctr, Cleveland, OH 4135 USA. RP Copland, E (reprint author), Case Western Reserve Univ, Dept Mat Sci & Engn, NASA Glenn Res Ctr, 21000 Brookpk Rd,MS 106-1, Cleveland, OH 4135 USA. EM evan.h.copland@grc.nasa.gov NR 25 TC 7 Z9 7 U1 0 U2 4 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD APR PY 2006 VL 38 IS 4 BP 443 EP 449 DI 10.1016/j.jct.2005.06.014 PG 7 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA 032PL UT WOS:000236786600012 ER PT J AU Lawson, JW Wolpert, DH AF Lawson, JW Wolpert, DH TI Adaptive programming of unconventional nano-architectures SO JOURNAL OF COMPUTATIONAL AND THEORETICAL NANOSCIENCE LA English DT Article DE nanoelectronics; computer architectures; circuit optimization; fault tolerance; machine learning; learning; adaptive methods; optimization; programmable circuits; control theory AB Novel assembly processes for nanocircuits could present compelling alternatives to the detailed design and placement currently used for computers. The resulting architectures however may not be programmable by standard means. In this paper, nanocomputers with unconventional architectures are programmed using adaptive methods. The internals of the device are treated as a "black box" and programming is achieved by manipulating "control voltages. " Learning algorithms are used to set the controls. As examples, logic gates and simple arithmetic circuits are implemented. Additionally, similar methods allow for reconfiguration of the devices, and makes them resistant to certain kinds of faults. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Lawson, JW (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. NR 13 TC 6 Z9 6 U1 0 U2 0 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1546-1955 J9 J COMPUT THEOR NANOS JI J. Comput. Theor. Nanosci. PD APR PY 2006 VL 3 IS 2 BP 272 EP 279 DI 10.1166/jctn.2006.011 PG 8 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 036PQ UT WOS:000237087500011 ER PT J AU Benson, CM Drdla, K Nedoluha, GE Shettle, EP Hoppel, KW Bevilacqua, RM AF Benson, CM Drdla, K Nedoluha, GE Shettle, EP Hoppel, KW Bevilacqua, RM TI Microphysical modeling of southern polar dehydration during the 1998 winter and comparison with POAM III observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTHERN-HEMISPHERE WINTER; STRATOSPHERIC ICE CLOUDS; SAGE-II; MIDDLE ATMOSPHERE; UNIFIED MODEL; AEROSOL; CONDENSATION; TROPOSPHERE; OZONE; EVAPORATION AB Stratospheric dehydration and high aerosol extinctions are examined for the 1998 Antarctic winter using the Integrated Microphysics and Aerosol Chemistry on Trajectories (IMPACT) model and data obtained by the Polar Ozone and Aerosol Measurement (POAM) III instrument. The model is applied to individual air parcels which are advected along 3-D trajectories using the United Kingdom Meteorological Office (UKMO) global wind and temperature fields. Model results are compared to water vapor and aerosol extinction measurements obtained with the POAM instrument. Results suggest that the water vapor mixing ratio at the end of the season is predicted with reasonable accuracy. However, dehydration occurs more rapidly in the simulation than is indicated by the POAM data. In addition to dehydration results, the frequency of high aerosol extinction measurements is examined for all model runs and compared to POAM data. The aerosol extinction comparisons are consistent with the assumption that heterogeneous nitric acid trihydrate (NAT) freezing occurs in approximately 1% of all particles. Various model parameters influencing ice cloud microphysics are altered to examine their effects on both the water vapor mixing ratio and high aerosol extinction events. While a reduction in the ice accommodation coefficient and an increase in the ice nucleation barrier both improve the agreement in the water vapor mixing ratio, the agreement in aerosol extinction is worsened. Extinction comparisons suggest that the model results are consistent with either high or low NAT-ice lattice compatibility factors, although intermediate values agree poorly with POAM data. The extent of dehydration is highly dependent on temperature; therefore, an uncertainty as small as +/- 1 K in the UKMO temperature fields may significantly change the model results. C1 USN, Res Lab, Washington, DC 20375 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Benson, CM (reprint author), Goddard Earth Sci & Technol Ctr, Baltimore, MD USA. EM benson@wvms.nrl.navy.mil NR 44 TC 6 Z9 6 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 1 PY 2006 VL 111 IS D7 AR D07201 DI 10.1029/2005JD006506 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031UV UT WOS:000236730700001 ER PT J AU Ozdogan, M Salvucci, GD Anderson, BT AF Ozdogan, M Salvucci, GD Anderson, BT TI Examination of the Bouchet-Morton complementary relationship using a mesoscale climate model and observations under a progressive irrigation scenario SO JOURNAL OF HYDROMETEOROLOGY LA English DT Article ID SOUTHWESTERN UNITED-STATES; ADVECTION-ARIDITY APPROACH; CONVECTIVE BOUNDARY-LAYER; REGIONAL SPECTRAL MODEL; HEAT-FLUX; POTENTIAL EVAPORATION; SURFACE; EVAPOTRANSPIRATION; AREAS; CIRCULATIONS AB The complementary relationship between actual and potential evaporation over southeastern Turkey was examined using a mesoscale climate model and field data. Model simulations of both actual and potential evaporation produce realistic temporal patterns in comparison to those estimated from field data; as evaporation from the surface increases with increasing irrigation, potential evaporation decreases. This is in accordance with the Bouchet-Morton complementary relationship and Suggests that actual evapotranspiration can be readily computed from routine meteorological observations. The driving mechanisms behind irrigation-related changes in actual and potential evaporation include reduced wind velocities, increased atmospheric stability, and depressed humidity deficits. The relative role of each in preserving the complementary relation is assessed by fitting a potential evaporation model to pan evaporation data. The importance of reduced wind velocity in maintaining complementarity was unexpected, and thus examined further using a set of perturbation simulation experiments with changing roughness parameters (reflecting growing cotton crops), changing moisture conditions (reflecting irrigation), and both. Three potential causes of wind velocity reduction associated with irrigation may be increased surface roughness, decreased thermal convection that influences momentum transfer, and the development of anomalous high pressure that counteracts the background wind field. All three are evident in the mesoscale model results, but the primary cause is the pressure-induced local wind system. The apparent necessity of capturing mesoscale dynamical feedbacks in maintaining complementarity between potential and actual evaporation suggests that a theory more complicated than current descriptions (which are based on feedbacks between actual evaporation and temperature and/or humidity gradients) is required to explain the complementary relationship. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Boston Univ, Dept Geog, Boston, MA 02215 USA. RP Ozdogan, M (reprint author), NASA, Goddard Space Flight Ctr, Code 614-3, Greenbelt, MD 20771 USA. EM ozdogan@hsb.gsfc.nasa.gov RI Salvucci, Guido/I-6185-2013; OI Ozdogan, Mutlu/0000-0002-1707-3375 NR 43 TC 26 Z9 28 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1525-755X EI 1525-7541 J9 J HYDROMETEOROL JI J. Hydrometeorol. PD APR PY 2006 VL 7 IS 2 BP 235 EP 251 DI 10.1175/JHM485.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 040OF UT WOS:000237388400002 ER PT J AU Holtzclaw, JD Sams, C AF Holtzclaw, J. David Sams, Clarence TI Decrease in T cell activation and calcium flux during clinorotation SO JOURNAL OF IMMUNOLOGY LA English DT Meeting Abstract CT Annual Meeting of the American-Association-of-Immunologists CY MAY 12-16, 2006 CL Boston, MA SP Amer Assoc Immunologists C1 Univ Space Res Assoc, Space Life Sci, Houston, TX 77008 USA. NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD APR 1 PY 2006 VL 176 SU S BP S178 EP S178 PG 1 WC Immunology SC Immunology GA 060YD UT WOS:000238837101320 ER PT J AU Salicru, AN Crucian, BE Sams, CF Actor, JK Marshall, GD AF Salicru, Adriano Nussa Crucian, Brian E. Sams, Clarence F. Actor, Jeffrey K. Marshall, Gailen D. TI In vitro catecholamine exposure produces variable effects on B7 costimulatory molecule expression in human monocytic cells SO JOURNAL OF IMMUNOLOGY LA English DT Meeting Abstract CT Annual Meeting of the American-Association-of-Immunologists CY MAY 12-16, 2006 CL Boston, MA SP Amer Assoc Immunologists C1 UTHSC, Dept Pathol & Lab Med, Houston, TX 77030 USA. NASA, JSC Bioastronaut, Houston, TX 77058 USA. UMMC, Div Clin Immunol & Allergy, Jackson, MS 39216 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD APR 1 PY 2006 VL 176 SU S BP S185 EP S185 PG 1 WC Immunology SC Immunology GA 060YD UT WOS:000238837101352 ER PT J AU Hishinuma, Y Yang, EH AF Hishinuma, Y Yang, EH TI Piezoelectric unimorph microactuator arrays for single-crystal silicon continuous-membrane deformable mirror SO JOURNAL OF MICROELECTROMECHANICAL SYSTEMS LA English DT Article DE adaptive optics; deformable mirror; PZT actuator; space telescopes; unimorph membrane actuator ID SYSTEMS AB Micromachined deformable mirror technology can boost the imaging performance of an otherwise nonrigid, lower-quality telescope structure. This paper describes the optimization of lead zirconium titanate (PZT) unimorph membrane microactuators for deformable mirrors. PZT unimorph actuators consisting of a variety of electrode designs, silicon-membrane thickness, and membrane sizes were fabricated and characterized. A mathematical model was developed to accurately simulate the membrane microactuator performance and to aid in the optimization of membrane thicknesses and electrode geometries. Excellent agreement was obtained between the model and the experimental results. Using the above approach, we have successfully demonstrated a 2.5-mm-diameter PZT unimorph actuator. A measured deflection of 5 mu m was obtained for 50 V applied voltage. Complete deformable mirror structures consisting of 10-mu m-thick single-crystal silicon mirror membranes mounted over the aforementioned 4 x 4 4 PZT unimorph membrane microactuator arrays were designed, fabricated, assembled, and optically characterized. The fully assembled deformable mirror showed an individual pixel stroke of 2.5 mu m at 50 V actuation voltage. The deformable mirror has a resonance frequency of 42 kHz and an influence function of approximately 25%. C1 Fuji Photo Film Co Ltd, Kanagawa 2588538, Japan. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Hishinuma, Y (reprint author), Fuji Photo Film Co Ltd, Kanagawa 2588538, Japan. EM Eui-Hyeok.yang@jpl.nasa.gov OI Yang, Eui-Hyeok/0000-0003-4893-1691 NR 15 TC 30 Z9 36 U1 2 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1057-7157 J9 J MICROELECTROMECH S JI J. Microelectromech. Syst. PD APR PY 2006 VL 15 IS 2 BP 370 EP 379 DI 10.1109/JMEMS.2006.8722229 PG 10 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 032JH UT WOS:000236770200011 ER PT J AU Hossain, TK MacLaren, S Engel, JM Liu, C Adesida, I Okojie, RS AF Hossain, TK MacLaren, S Engel, JM Liu, C Adesida, I Okojie, RS TI The fabrication of suspended micromechanical structures from bulk 6H-SiC using an ICP-RIE system SO JOURNAL OF MICROMECHANICS AND MICROENGINEERING LA English DT Article ID ATOMIC-FORCE MICROSCOPE; SILICON-CARBIDE AB We have successfully fabricated freestanding single-crystal 6H-SiC cantilevers of several microns size using bulk micromachining with all inductively coupled plasma reactive ion etching system. We have also used these SiC cantilever structures to measure Young's modulus through the use of an atomic force microscope. The measurements were performed on a series of 13 mu m thick and 20 mu m wide cantilevers with lengths ranging from 100 mu m to 350 mu m. The average measured Young's modulus of 441 GPa is in excellent agreement with the documented values in the literature. C1 Univ Illinois, Micro & Nanotechnol Lab, Urbana, IL 61801 USA. Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. Univ Illinois, Frederick Seitz Mat Res Lab, Ctr Microanal Mat, Urbana, IL 61801 USA. NASA, Cleveland, OH USA. RP Hossain, TK (reprint author), Univ Illinois, Micro & Nanotechnol Lab, Urbana, IL 61801 USA. RI Liu, Chang/B-7249-2009; MacLaren, Scott/A-5075-2009 NR 16 TC 20 Z9 20 U1 1 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0960-1317 J9 J MICROMECH MICROENG JI J. Micromech. Microeng. PD APR PY 2006 VL 16 IS 4 BP 751 EP 756 DI 10.1088/0960-1317/16/4/011 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 039NK UT WOS:000237312600012 ER PT J AU Predoi-Cross, A Brawley-Tremblay, M Brown, LR Devi, VM Benner, DC AF Predoi-Cross, A Brawley-Tremblay, M Brown, LR Devi, VM Benner, DC TI Multispectrum analysis of (CH4)-C-12 from 4100 to 4635 cm(-1): II. Air-broadening coefficients (widths and shifts) SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE methane; octad; air-broadening; widths; pressure shifts ID BAND Q-BRANCH; TEMPERATURE-DEPENDENCE; SPECTRAL REGION; METHANE LINES; FREQUENCY; HITRAN; LASER AB Room temperature Lorentz air-broadened halfwidth and pressure-induced air-shift coefficients were measured for 10 11 transitions in the octad region of methane between 4100 and 4635 cm(-1). These measurements were made by analyzing 10 laboratory absorption spectra recorded at 0.011 cm(-1) resolution using the McMath-Pierce Fourier transform spectrometer located at the National Solar Observatory on Kitt Peak, Arizona. The spectra were obtained using two absorption cells with path lengths of 2.05 and 150 cm. The total sample pressures ranged from 99 to 400 torr with CH4 volume mixing ratios of 0.01 in dry air. The spectral line parameters were retrieved using a multispectrum nonlinear least squares technique. Transitions belonging to five bands of the octad polyad were observed, namely v(2) + 2v(4), v(1) + v(4), v(3) + v(4), 2v(2) + v(4), and v(2) + v(3). The numbers of measurements by bands are: 33 for v(2) + 2v(4), 180 for v(1) + v(4), 635 for v(3) + v(4), 33 for 2v(2) + v(4), and 130 for v(2) + v(3). Transitions with rotational quantum number J up to 16 are included in the analysis. The measured width and shift coefficients vary according to the tetrahedral symmetry species and the rotational quantum numbers of the transitions. The retrieved parameters from this study are compared with prior results, in part to estimate absolute accuracy and determine the extent of vibrational dependence of widths and shifts. (C) 2006 Elsevier Inc. All rights reserved. C1 Univ Lethbridge, Dept Phys, Lethbridge, AB T1K 3M4, Canada. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. RP Predoi-Cross, A (reprint author), Univ Lethbridge, Dept Phys, 4401 Univ Dr, Lethbridge, AB T1K 3M4, Canada. EM adriana.predoicross@uleth.ca NR 18 TC 34 Z9 34 U1 0 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD APR PY 2006 VL 236 IS 2 BP 201 EP 215 DI 10.1016/j.jms.2006.01.013 PG 15 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 036LH UT WOS:000237072100007 ER PT J AU Drouin, BJ Maiwald, FW AF Drouin, BJ Maiwald, FW TI Extended THz measurements of nitrous oxide, N2O SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE nitrous oxide; submillimeter; THz; wavelength calibration ID ROTATIONAL TRANSITIONS; SUBMILLIMETER; SPECTROSCOPY; MILLIMETER; SPECTRUM AB High precision measurements of the atmospheric trace gas nitrous oxide have been extended up through 1.5 THz. The data set includes ground state, v(2), 2v(2), (NNO)-N-15, (NNO)-N-15, and (N2O)-O-18 spectra up to J = 68. Improved Hamiltonian parameters are given. (C) 2006 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Drouin, BJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM brian.j.drouin@jpl.nasa.gov NR 14 TC 8 Z9 8 U1 1 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD APR PY 2006 VL 236 IS 2 BP 260 EP 262 DI 10.1016/j.jms.2006.01.005 PG 3 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 036LH UT WOS:000237072100013 ER PT J AU Han, WQ Shinoda, T Fu, LL McCreary, JP AF Han, Weiqing Shinoda, Toshiaki Fu, Lee-Lueng McCreary, Julian P. TI Impact of atmospheric intraseasonal oscillations on the Indian Ocean dipole during the 1990s SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID MADDEN-JULIAN OSCILLATION; GENERAL-CIRCULATION MODEL; 1997-98 EL-NINO; INTERANNUAL VARIABILITY; EQUATORIAL; DYNAMICS; CONVECTION; PACIFIC; MONSOON; ANOMALIES AB Effects of atmospheric intraseasonal oscillations (ISOs) on the Indian Ocean zonal dipole mode (IOZDM) are investigated by analyzing available observations and a suite of solutions to an ocean general circulation model, namely, the Hybrid Coordinate Ocean Model (HYCOM). Data and model solutions for the period 1991-2000 are analyzed, a period that includes two strong IOZDM events, during 1994 and 1997, and a weak one, in 1991. Both the data analysis and model results suggest that atmospheric ISOs play a significant role in causing irregularity of the two strong IOZDM events and the premature termination of the weak one. Of particular interest is a basinwide, wind-driven oceanic resonance with a period near 90 days, involving the propagation of equatorial Kelvin and first-meridional-mode Rossby waves across the basin. Before the onset of the strong 1997 dipole, wind variability had significant power near 90 days, and the resonance was strongly excited. Associated with the resonance was a deepened thermocline in the eastern basin during August and early September, which reduced the upwelling in the eastern antinode region of the IOZDM, thereby delaying the reversal of the equatorial zonal SST gradient-an important indicator of a strong IOZDM-by over a month. A similar deepened thermocline in the eastern basin also contributed to the premature termination of the weak 1991 dipole. During the 1994 IOZDM, the winds had little power near 90 days, and the resonant mode was not prominent. The ISOs influenced the IOZDM through both surface fluxes and thermocline variability. They enhanced warming in the western antinode region during October, the peak phase of the IOZDM, intensifying its strength. During November, strong winds significantly cooled the western and central basin through upwelling and surface fluxes, cooling SST there and contributing to the early and quick termination of the 1994 event. C1 Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Climate Diagnost Ctr, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ Hawaii Manoa, Int Pacific Res Ctr, Honolulu, HI 96822 USA. RP Han, WQ (reprint author), Univ Colorado, Program Atmospher & Ocean Sci, UCB 311, Boulder, CO 80309 USA. EM whan@enso.colorado.edu RI Shinoda, Toshiaki/J-3745-2016 OI Shinoda, Toshiaki/0000-0003-1416-2206 NR 57 TC 31 Z9 33 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 EI 1520-0485 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD APR PY 2006 VL 36 IS 4 BP 670 EP 690 DI 10.1175/JPO2892.1 PG 21 WC Oceanography SC Oceanography GA 047NX UT WOS:000237887100007 ER PT J AU Yan, XH Jo, YH Liu, WT He, MX AF Yan, Xiao-Hai Jo, Young-Heon Liu, W. Timothy He, Ming-Xia TI A new study of the Mediterranean outflow, air-sea interactions, and meddies using multisensor data SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID MIXED-LAYER DEPTH; SINGULAR-VALUE DECOMPOSITION; SURFACE TEMPERATURE; NORTH-ATLANTIC; SEMAPHORE EXPERIMENT; COUPLED PATTERNS; ANALYTICAL MODEL; CANARY BASIN; AZORES FRONT; SALT LENS AB Previous studies of the Mediterranean Sea outflow and meddies (O&M) were limited by the poor spatial and temporal resolution of conventional in situ observations as well as the confinement of satellite observations to the ocean's surface. Accordingly, little is known about the formation and transport of meddies and the spatial and temporal variation of O&M trajectories, which are located, on average, at a depth of 1000 m. However, a new remote sensing method has been developed by the authors to observe and study the O&M through unique approaches in satellite multisensor data integration analyses. Satellite altimeter, scatterometer, infrared satellite imagery, and XBT data were used to detect and calculate the trajectories and the relative transport of the O&M (January 1993-December 2002). Two experiments [covering 199395: A Mediterranean Undercurrent Seeding Experiment (AMUSE) and Structures des Echanges MerAtmosphere, Proprietes des Heterogeneites Oceaniques: Recherche Experimentale (SEMAPHORE)] and XBT temperature measurements were used to directly validate the method presented herein. The monthly mean features derived from floats and XBTs for multiple meddies and the results of the presented method were significantly correlated based on a statistical chi-square test. In addition, the complex singular value decomposition method was used to identify the propagating features and their phase speeds. It was found that saltier water from the Mediterranean Sea was transported into the North Atlantic Ocean over the Strait of Gibraltar in boreal spring and summer relative to boreal autumn and winter. Streamfunctions using altimetry, and time-frequency energy distributions using the Hilbert-Huang transform, were computed to evaluate the meddy interactions with the sea surface variation. Since the O&M play a significant role in carrying salty water from the Mediterranean Sea into the Atlantic, such new knowledge about their trajectories, transport, and life histories is important to the understanding of their mixing and interaction with North Atlantic water. This may lead to a better understanding of the global ocean circulation and global climate change. C1 Univ Delaware, Grad Coll Marine Studies, Newark, DE 19716 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Ocean Univ Qingdao, Ocean Remote Sensing Inst, Qingdao 266003, Peoples R China. RP Yan, XH (reprint author), Univ Delaware, Grad Coll Marine Studies, Newark, DE 19716 USA. EM xiaohai@udel.edu NR 41 TC 13 Z9 13 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 EI 1520-0485 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD APR PY 2006 VL 36 IS 4 BP 691 EP 710 DI 10.1175/JPO2873.1 PG 20 WC Oceanography SC Oceanography GA 047NX UT WOS:000237887100008 ER PT J AU Martin, WF Cerundolo, LH Pikosky, MA Gaine, PC Maresh, CM Armstrong, LE Bolster, DR Rodriguez, NR AF Martin, WF Cerundolo, LH Pikosky, MA Gaine, PC Maresh, CM Armstrong, LE Bolster, DR Rodriguez, NR TI Effects of dietary protein intake on indexes of hydration SO JOURNAL OF THE AMERICAN DIETETIC ASSOCIATION LA English DT Article ID CARBOHYDRATE; PROGRESSION; WEIGHT AB This study aims to characterize the relationship between increased protein intake and hydration indexes. Five men participated in a 12-week, randomized, crossover, controlled diet intervention study. Subjects consumed eucaloric diets containing 3.6 (high protein), 1.8 (moderate protein), and 0.8 (low protein) g/kg/day of protein for 4 weeks each. Energy intakes were based on requirements established relative to resting energy expenditure and activity at baseline. Assessments included blood urea nitrogen, plasma osmolality, urine-specific gravity, and estimates of fluid balance. Repeated-measures analyses of variance and paired t tests were used to determine effects of treatment and time. Fluid intake and fluid balance were unaffected. Blood urea nitrogen was higher for high protein vs low protein and vs moderate protein, and urine-specific gravity was higher for high protein vs moderate protein. Baseline plasma osmolality was greater for high protein vs low protein and vs moderate protein. The effect of increasing dietary protein on fluid status was minimal. C1 Univ Connecticut, Dept Nutr Sci, Storrs, CT 06269 USA. Shaklee Corp, Pleasanton, CA USA. Metro W Med Ctr, Framingham, MA USA. USARIEM, Natick, MA USA. Univ Connecticut, Dept Kinesiol, Storrs, CT 06269 USA. NASA, Houston, TX USA. RP Rodriguez, NR (reprint author), Univ Connecticut, Dept Nutr Sci, Unit 4017, Storrs, CT 06269 USA. EM nancy.rodriguez@uconn.edu NR 12 TC 20 Z9 20 U1 1 U2 5 PU AMER DIETETIC ASSOC PI CHICAGO PA 216 W JACKSON BLVD #800, CHICAGO, IL 60606-6995 USA SN 0002-8223 J9 J AM DIET ASSOC JI J. Am. Diet. Assoc. PD APR PY 2006 VL 106 IS 4 BP 587 EP 589 DI 10.1016/j.jada.2006.01.011 PG 3 WC Nutrition & Dietetics SC Nutrition & Dietetics GA 028PB UT WOS:000236499200016 PM 16567155 ER PT J AU Kottapalli, S AF Kottapalli, S TI Neural network modeling of UH-60A pilot vibration SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY LA English DT Article; Proceedings Paper CT 4th Decennial Specialists Conference on Aeromechanics CY JAN 21-23, 2004 CL San Francisco, CA SP Amer Helicopter Soc AB Full-scale flight-test pilot floor vibration is modeled using neural networks and full-scale wind tunnel test data for low speed level flight conditions. Neural network connections between the wind tunnel test data and the three flight test pilot vibration components (vertical, lateral, and longitudinal) are studied. Two full-scale UH-60A Black Hawk databases are used. The first database is the NASA/Army UH-60A Airloads Program flight test database. The second database is the UH-60A rotor-only wind tunnel database that was acquired in the NASA Ames 80- by 120-Foot Wind Tunnel with the Large Rotor Test Apparatus (LRTA). Using neural networks, the flight-test pilot vibration is modeled using the wind tunnel rotating system hub accelerations, and separately, using the hub loads. The results show that the wind tunnel rotating system hub accelerations and the operating parameters can represent the flight test pilot vibration. The six components of the wind tunnel N/rev balance-system hub loads and the operating parameters can also represent the flight test pilot vibration. The present neural network connections can significantly increase the value of wind tunnel testing. C1 NASA, Ames Res Ctr, Flight Vehicle Res & Technol Div, Moffett Field, CA 94035 USA. RP Kottapalli, S (reprint author), NASA, Ames Res Ctr, Flight Vehicle Res & Technol Div, Moffett Field, CA 94035 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU AMER HELICOPTER SOC INC PI ALEXANDRIA PA 217 N WASHINGTON ST, ALEXANDRIA, VA 22314 USA SN 0002-8711 J9 J AM HELICOPTER SOC JI J. Am. Helicopter Soc. PD APR PY 2006 VL 51 IS 2 BP 195 EP 201 PG 7 WC Engineering, Aerospace SC Engineering GA 041XC UT WOS:000237488900007 ER PT J AU Cheng, RP Tischler, MB Schulein, GJ AF Cheng, RP Tischler, MB Schulein, GJ TI R-MAX helicopter state-space model identification for hover and forward-flight SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY LA English DT Article AB This paper presents the Yamaha R-MAX helicopter hover and forward-flight state-space models computed from flight test data using a frequency-domain system identification method. The derived identified models show good agreement with the flight test data in both the frequency and time domains. The coupled rotor/stabilizer/fuselage dynamics are identified using a hybrid equation formulation, which is summarized in this paper. The vehicle response is dominated by the lightly damped coupled rotor/stabilizer/fuselage modes that were identified in the 10-25 rad/sec range. The identified state-space models presented herein are useful for flight dynamics, control, and simulation studies of rotorcraft unmanned aerial vehicles based on the Yamaha R-MAX. C1 NASA, Ames Res Ctr, Aeroflightdynam Directorate, Moffett Field, CA 94035 USA. San Jose State Univ, Ames Res Ctr, Moffett Field, CA USA. RP Cheng, RP (reprint author), NASA, Ames Res Ctr, Aeroflightdynam Directorate, Moffett Field, CA 94035 USA. NR 14 TC 13 Z9 15 U1 0 U2 4 PU AMER HELICOPTER SOC INC PI ALEXANDRIA PA 217 N WASHINGTON ST, ALEXANDRIA, VA 22314 USA SN 0002-8711 J9 J AM HELICOPTER SOC JI J. Am. Helicopter Soc. PD APR PY 2006 VL 51 IS 2 BP 202 EP 210 PG 9 WC Engineering, Aerospace SC Engineering GA 041XC UT WOS:000237488900008 ER PT J AU Anicich, VG Wilson, PF McEwan, MJ AF Anicich, VG Wilson, PF McEwan, MJ TI An ICR study of ion-molecules reactions relevant to titan's atmosphere: An investigation of binary hydrocarbon mixtures up to 1 micron SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID CHEMISTRY; C2H4; ASSOCIATION; IONOSPHERE; KINETICS; CH4 AB Results are reported for studies of binary mixtures of hydrocarbons exposed to low-energy electron impact ionization. A variety of experimental methods are used: conventional ICR mass spectrometry, the standard double resonance in an ICR for determination of the precursor ions, and the modulated double resonance ejection in an ICR for the determination of the daughter ions. A flowing afterglow-selected ion flow tube experiment (FA-SIFT) was used for validation and examination of termolecular reactions. An extensive database of reaction kinetics already exists for many of these reactions. The main point of this study was the determination of the accuracy of this database and the identification of missing reactions and reaction channels. An effort was made to extend the study to the highest pressures possible to determine if any important termolecular reaction channels were present that were not recognized in earlier investigations. A new approach was used here. In the binary mixtures of hydrocarbon gases, mass spectra were obtained as a function of independent pressure changes of both gases. All the mass peaks in the spectra were fitted using existing kinetic data as a starting point. A model of the ion abundances was then produced from the solution of the partial differential equations derived from the kinetics in terms of reaction rate coefficients and initial abundances. The model was fitted to the data for all of the pressures by a least-squares fit to the reaction rate coefficients and initial abundances. The kinetic parameters were then adjusted if required. C1 Univ Canterbury, Dept Chem, Christchurch 1, New Zealand. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP McEwan, MJ (reprint author), Univ Canterbury, Dept Chem, PB 4800, Christchurch 1, New Zealand. EM murray.mcewan@canterbury.ac.nz NR 19 TC 21 Z9 21 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD APR PY 2006 VL 17 IS 4 BP 544 EP 561 DI 10.1016/j.jasms.2005.11.022 PG 18 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 031OF UT WOS:000236713200008 PM 16503159 ER PT J AU D'Amario, LA AF D'Amario, Louis A. TI Mars exploration rovers navigation results SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article; Proceedings Paper CT AIAA/AAS Astrodynamics Specialist Conference CY AUG 15-19, 2004 CL Providence, RI SP Amer Inst Aeronaut & Astronaut, AAS AB The twin Mars Exploration Rovers, Spirit and Opportunity, were launched on June 10, 2003(3) and July 8, 2003, from Cape Canaveral, Florida. Spirit and Opportunity were targeted for landings at Gusev Crater (arrival on January 4, 2004) and Meridiani Planum (arrival on January 25, 2004). The primary navigation challenge was to deliver each spacecraft to the desired atmospheric entry interface point with sufficient accuracy such that each lander would touch down within a specified landing ellipse (about 70 km X 5 km) determined to be safe for landing and also judged to be scientifically interesting. In order to achieve landing within the target ellipse, precise control of the inertial entry flight path angle (FPA) at atmospheric entry was required. The maximum allowable errors in FPA following TCM-5 (trajectory correction maneuver #5) at Entry (E) - 2 days were +/- 0.12 degrees (3 sigma) for Spirit and +/- 0.14 degrees (3 sigma) for Opportunity. Achieving these entry delivery accuracies necessitated significant improvements to the interplanetary navigation system used for MER. These improvements included new processes and software for orbit determination, propulsive maneuver design, and entry, descent, and landing (EDL) trajectory simulation. The actual achieved atmospheric entry accuracies for Spirit and Opportunity significantly exceeded the requirements. At the navigation data cutoff for the TCM-5 final design, the orbit determination FPA knowledge error was +/- 0.028 degrees (3 sigma) for Spirit and +/- 0.035 degrees (3 sigma) for Opportunity. Because of exceptionally accurate navigation performance, TCM-5 (E - 2 days) and TCM-6 (E - 4 hours) were canceled for both Spirit and Opportunity. The actual landing locations (determined from in-situ Doppler tracking between the MER rovers and the Mars Odyssey orbiter) differed from the target landing points by 10.1 km (downtrack) for Spirit and 24.6 km (downtrack) for Opportunity. The majority of the landing position offsets for both landers was primarily caused by variations in atmosphere and spacecraft aerodynamic modeling from what was predicted. The amount of the landing position offset caused by navigation-only errors was only 3.3 km (uptrack) for Spirit and 9.7 km (downtrack) for Opportunity. C1 CALTECH, Jet Prop Lab, Guidance Navigat & Control SEct, Pasadena, CA 91109 USA. RP D'Amario, LA (reprint author), CALTECH, Jet Prop Lab, Guidance Navigat & Control SEct, MS 301-125L, Pasadena, CA 91109 USA. NR 10 TC 3 Z9 5 U1 0 U2 4 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD APR-JUN PY 2006 VL 54 IS 2 BP 129 EP 173 PG 45 WC Engineering, Aerospace SC Engineering GA 136IC UT WOS:000244214800002 ER PT J AU Wawrzyniak, G Baird, D Graat, E McElrath, T Portock, B Watkins, M AF Wawrzyniak, Geoffrey Baird, Darren Graat, Eric McElrath, Tim Portock, Brian Watkins, Michael TI Mars exploration rovers orbit determination system modeling SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article; Proceedings Paper CT AIAA/AAS Astrodynamics Specialist Conference CY AUG 15-19, 2004 CL Providence, RI SP Amer Inst Aeronaut & Astronaut, AAS AB From June 2003 to January 2004, two spinning spacecraft journeyed from Earth to Mars. A team of navigators at the Jet Propulsion Laboratory (JPL) accurately determined the orbits of both Mars Exploration Rovers, Spirit and Opportunity. For the navigation process to be successful, the team needed to know how nongravitational effects and how measurement system properties affected the trajectory and data modeling. To accomplish this, in addition to the standard gravitational and radiometric modeling of the spacecraft, a calibration was performed on each spacecraft to determine the amount of Delta V that might occur during a turn, a high-fidelity solar-radiation-pressure model was created, the spin signature was removed from the tracking data, the station locations of the Deep Space Network were resurveyed, and a model of interplanetary charged particles was developed. The result of this effort was near-perfect accuracy, surpassing the tight atmospheric-entry requirements for navigation of both spacecraft. C1 CALTECH, Jet Prop Lab, Guidance Navigat & Control Sect, Pasadena, CA 91109 USA. CALTECH, Jet Prop Lab, Mars Sci Lab, Pasadena, CA 91109 USA. RP Wawrzyniak, G (reprint author), Purdue Univ, Sch Aeronaut & Astronaut, Grissom Hall,315 N Grant St, W Lafayette, IN 47907 USA. NR 13 TC 0 Z9 0 U1 1 U2 1 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD APR-JUN PY 2006 VL 54 IS 2 BP 175 EP 197 PG 23 WC Engineering, Aerospace SC Engineering GA 136IC UT WOS:000244214800003 ER PT J AU Russell, RP AF Russell, Ryan P. TI Global search for planar and three-dimensional periodic orbits near Europa SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article; Proceedings Paper CT AIAA/AAS Astrodynamics Specialist Conference CY AUG 07-11, 2005 CL Lake Tahoe, CA SP Amer Inst Aeronaut & Astronaut, Amer Astronaut Soc ID RESTRICTED 3-BODY PROBLEM; STABILITY; FAMILIES; POINTS AB A global grid search is performed to find axi- and doubly-symmetric periodic orbits in the restricted three-body problem using the dimensioned parameters associated with the Jupiter-Europa system. Local differential correctors are applied to regions of the initial condition phase space that appear to be near solutions. A three-dimensional initial condition mesh with billions of nodes is evaluated, and over 600,000 periodic solutions are identified. Families of direct and retrograde solutions, both new and previously published, are identified and discussed. Stability is analyzed for each solution and general regions of stability are noted. Of the most promising results is the observation and characterization of a large class of stable yet highly-inclined direct orbits. Finally, all of the solutions and associated properties are archived. The resulting database is a practical reference for preliminary design of missions to Europa. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Russell, RP (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 301-121, Pasadena, CA 91109 USA. EM Ryan.Russell@jpl.nasa.gov NR 31 TC 30 Z9 30 U1 0 U2 1 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD APR-JUN PY 2006 VL 54 IS 2 BP 199 EP 226 PG 28 WC Engineering, Aerospace SC Engineering GA 136IC UT WOS:000244214800004 ER PT J AU Begault, DR Anderson, MR McClain, BU AF Begault, DR Anderson, MR McClain, BU TI Spatially modulated auditory alerts for aviation SO JOURNAL OF THE AUDIO ENGINEERING SOCIETY LA English DT Article ID DETECTABILITY AB The technique of spatially modulating an existing or newly created auditory alert along a virtual trajectory to improve its detection in a noisy environment is described. Threshold data from 14 participants were gathered as a function of the spatial modulation rate (0, 1.6, and 3.3 Hz) of an avionics "wind sheer" alert (two successive 300-ms square waves) against a steady-state background noise (Boeing 737-300 flight deck ambient sound). The 70.7% detection threshold for the spatially modulated alert was on average 7.8 dB lower than that for an alert without spatial modulation, with noise and signal both presented over headphones using virtual simulation techniques. The threshold for a headphone-delivered spatially modulated alert was 13.4 dB lower than that for a nonmodulated alert delivered over a single loudspeaker. C1 NASA, Ames Res Ctr, Spatial Auditory Display Lab, Human Syst Integrat Div, Moffett Field, CA 94035 USA. QSS Grp Inc, Moffett Field, CA 94035 USA. San Jose State Univ Fdn, San Jose, CA 95122 USA. RP Begault, DR (reprint author), NASA, Ames Res Ctr, Spatial Auditory Display Lab, Human Syst Integrat Div, Moffett Field, CA 94035 USA. EM Durand.R.Begault@nasa.gov; madnerson@mail.arc.nasa.gov; bmcclain@activecomm.net NR 14 TC 2 Z9 2 U1 0 U2 1 PU AUDIO ENGINEERING SOC PI NEW YORK PA 60 E 42ND ST, NEW YORK, NY 10165-2520 USA SN 1549-4950 J9 J AUDIO ENG SOC JI J. Audio Eng. Soc. PD APR PY 2006 VL 54 IS 4 BP 276 EP 282 PG 7 WC Acoustics; Engineering, Multidisciplinary SC Acoustics; Engineering GA 043OR UT WOS:000237611300002 ER PT J AU Bose, D Wright, MJ Bogdanoff, DW Raiche, GA Allen, GA AF Bose, D Wright, MJ Bogdanoff, DW Raiche, GA Allen, GA TI Modeling and experimental assessment of CN radiation behind a strong shock wave SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article; Proceedings Paper CT AIAA 43rd Aerospace Sciences Meeting and Exhibit CY JAN 10-13, 2005 CL Reno, NV SP AIAA ID RELAXATION; RED AB Assessment of nonequilibrium thermochemical models for shock-layer radiation in N-2/CH4 mixtures is presented via comparisons with spectrally and temporally resolved intensity measurements from a set of shock tube experiments. The experiments were carried out at the Electric Arc Shock Tube facility at NASA Ames Research Center in a rarified environment [13.3-133.3 Pa (0.1 and 1 torr)] representative of the peak heating conditions of a Titan aerocapture trajectory (5-9 km/s). The baseline model that assumes a Boltzmann population of the CN excited states consistently overpredicts the shock-layer radiation intensity at lower pressure [13.3 Pa (0.1 torr)]. A nonlocal collisional radiative model that solves a simplified master equation and includes radiative transport and nonlocal absorption in the shock tube is presented. The proposed model improves the prediction of the nonequilibrium radiation overshoot peak, but still underpredicts the intensity decay rate in the low-pressure case. Further analysis suggests possible reasons for the remaining disagreement, the most likely being a slow CN consumption in the current chemical kinetics model in the intensity fall-off region. C1 NASA, Ames Res Ctr, Ion Amer Corp, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, ELORET Corp, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Reacting Flow Environm Branch, Moffett Field, CA 94035 USA. RP Bose, D (reprint author), NASA, Ames Res Ctr, Ion Amer Corp, Moffett Field, CA 94035 USA. EM bosedeepak@hotmail.com NR 32 TC 23 Z9 25 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD APR-JUN PY 2006 VL 20 IS 2 BP 220 EP 230 DI 10.2514/1.16869 PG 11 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 039TR UT WOS:000237330600005 ER PT J AU Sun, GY AF Sun, GY TI Auxiliary bearing life prediction using Hertzian contact bearing model SO JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME LA English DT Article AB A rotating machine with active magnetic bearings (AMBs) requires conventional hearings as a backup support system in the case of AMB failure. This paper presents all estimated auxiliary/catcher bearing (CB) L-10 fatigue life based oil the Hertzian contact dynamic loads between bearing ball and races during the touchdown. The thermal growths of bearing components are predicted using a one-dimensional thermal model, and the resulting expansions contribute to the calculation for the Hertzian contact loads. Numerical simulations for all energy-storage flywheel module reveal that a high-speed backward whirl significantly reduces the CB life and that all optimal damping lowers the CB temperature and increases the CB life. C1 NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. RP Sun, GY (reprint author), NASA, John H Glenn Res Ctr, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM guangdol@hotmail.com NR 12 TC 7 Z9 9 U1 0 U2 6 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1048-9002 J9 J VIB ACOUST JI J. Vib. Acoust.-Trans. ASME PD APR PY 2006 VL 128 IS 2 BP 203 EP 209 DI 10.1115/1.2159036 PG 7 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 033CZ UT WOS:000236825400010 ER PT J AU Goldstein, T Gulland, FMD Braun, RC Antonelis, GA Kashinsky, L Rowles, TK Mazet, JAK Dalton, LM Aldridge, BM Stott, JL AF Goldstein, T Gulland, FMD Braun, RC Antonelis, GA Kashinsky, L Rowles, TK Mazet, JAK Dalton, LM Aldridge, BM Stott, JL TI Molecular identification of a novel gamma herpesvirus in the endangered Hawaiian monk seal (Monachus schauinslandi) SO MARINE MAMMAL SCIENCE LA English DT Article ID PACIFIC HARBOR SEALS; PHOCA-VITULINA-RICHARDSII; CALIFORNIA; INFECTION; MORTALITY; OUTBREAK C1 Marine Mammal Ctr, Sausalito, CA 95965 USA. Pacific Isl Fisheries Ctr, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. Off Protected Resources, Natl Marine Fisheries Serv, Silver Spring, MD 20910 USA. Univ Calif Davis, Sch Vet Med, Wildlife Hlth Ctr, Davis, CA 95616 USA. Sea World Texas, San Antonio, TX 78251 USA. Univ Calif Davis, Sch Vet Med, Dept Pathol Microbiol & Immunol, Davis, CA 95616 USA. RP Goldstein, T (reprint author), Marine Mammal Ctr, 1065 Fort Cronkhite,Golden Gate Recreat Area, Sausalito, CA 95965 USA. EM goldsteint@tmmc.org RI Mazet, Jonna/B-4811-2012 NR 18 TC 10 Z9 11 U1 1 U2 5 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD APR PY 2006 VL 22 IS 2 BP 465 EP 471 DI 10.1111/j.1748-7692.2006.00025.x PG 7 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 028ZS UT WOS:000236527900015 ER PT J AU Bar-Cohen, Y Lih, SS Bao, XQ Sherrit, S AF Bar-Cohen, Y Lih, SS Bao, XQ Sherrit, S TI Ferroelectric based single source of multiple types of radiation enabling multifunctional NDT and analytical instruments SO MATERIALS EVALUATION LA English DT Article DE radiation source; multifunctional instruments; Ferrosource; ferroelectric radiation emitter AB The use of nondestructive testing (NDT) techniques to examine planetary samples for the presence of water, biomarkers and minerals supports NASA objectives for future exploration missions. Determination of the surface and bulk properties of select samples currently requires multiple instruments, each with an independent type of radiation source. Using a multitude of instruments may require high power, mass and volume. Recently, the authors demonstrated a ferroelectric based radiation source, called Ferrosource, that Was shown to emit five radiation types enabling a new generation of compact, low power, 1070 mass multifunctional NDT analytical instruments. The emitted radiation types include visible light, ultraviolet, X-ray, as well as electron and ion beams. These radiation types are already tinder development for detecting water, performing mineralogical/chemical analysis and for identifying biological markers. This ferroelectric based source consists of a disk having a continuous ground electrode on one side and a grid shaped cathode on the other side. This source is placed in a vacuum tube and is used to generate plasma by switching high voltage pulses; the plasma is harnessed to generate the radiation. A series of experiments Was performed to demonstrate the emission of the five radiation types and the results are described and discussed herein. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bar-Cohen, Y (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM yosi@jpl.nasa.gov NR 5 TC 1 Z9 1 U1 1 U2 1 PU AMER SOC NONDESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 USA SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD APR PY 2006 VL 64 IS 4 BP 407 EP 411 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA 029ZI UT WOS:000236602500007 ER PT J AU McDowell, M Gray, E Rogers, RB AF McDowell, M Gray, E Rogers, RB TI An autonomous phase-boundary detection technique for colloidal hard sphere suspension experiments SO MICROSCOPY RESEARCH AND TECHNIQUE LA English DT Article DE microscopy; transition mapping; autonomous interface detection; machine vision ID PHOTONIC CRYSTALS AB Colloidal suspensions of monodisperse spheres are used as physical models of thermodynamic phase transitions and as precursors to photonic band gap materials. Current techniques for identifying the phase boundaries involve manually identifying the phase transitions, which is very tedious and time-consuming. In addition, current image analysis techniques are not able to distinguish between densely packed phases within conventional microscope images, which are mainly characterized by degrees of randomness or order with similar grayscale value properties. We have developed an intelligent machine vision technique that automatically identifies colloidal phase boundaries. The technique utilizes intelligent image processing algorithms that accurately identify and track phase changes vertically or horizontally for a sequence of colloidal hard sphere suspension images. This technique is readily adaptable to any imaging application wherein regions of interest are distinguished from the background by differing patterns of motion over time. C1 NASA, Glenn Res Ctr, Micrograv Div, Cleveland, OH 44135 USA. Sci Consulting Inc, Cleveland, OH 44135 USA. RP McDowell, M (reprint author), NASA, Glenn Res Ctr, Micrograv Sci Div, Mail Stop 105-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM drmm@easy.grc.nasa.gov NR 14 TC 0 Z9 0 U1 1 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1059-910X J9 MICROSC RES TECHNIQ JI Microsc. Res. Tech. PD APR PY 2006 VL 69 IS 4 BP 236 EP 245 DI 10.1002/jemt.20264 PG 10 WC Anatomy & Morphology; Biology; Microscopy SC Anatomy & Morphology; Life Sciences & Biomedicine - Other Topics; Microscopy GA 033TP UT WOS:000236872700002 PM 16586491 ER PT J AU Arevalo, P Uttley, P AF Arevalo, P Uttley, P TI Investigating a fluctuating-accretion model for the spectral-timing properties of accreting black hole systems SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; galaxies : active ID X-RAY VARIABILITY; ACTIVE GALACTIC NUCLEI; CYGNUS X-1; POWER SPECTRA; SOFT STATE; NGC-4051; LONG; MCG-6-30-15; GALAXIES; NOISE AB The fluctuating-accretion model of Lyubarskii and its extension by Kotov, Churazov & Gilfanov seek to explain the spectral-timing properties of the X-ray variability of accreting black holes in terms of inward-propagating mass accretion fluctuations produced at a broad range of radii. The fluctuations modulate the X-ray emitting region as they move inwards and can produce temporal-frequency-dependent lags between energy bands, and energy-dependent power spectral densities (PSDs) as a result of the different emissivity profiles, which may be expected at different X-ray energies. Here, we use a simple numerical implementation to investigate in detail the X-ray spectral-timing properties of the model and their relation to several physically interesting parameters, namely the emissivity profile in different energy bands, the geometrical thickness and viscosity parameter of the accretion flow, the strength of damping on the fluctuations and the temporal coherence (measured by the 'quality factor', Q) of the fluctuations introduced at each radius. We find that a geometrically thick flow with large viscosity parameter is favoured, and we confirm that the predicted lags are quite robust to changes in the emissivity profile and physical parameters of the accretion flow, which may help to explain the similarity of the lag spectra in the low/hard and high/soft states of Cyg X-1. We also demonstrate the model regime where the light curves in different energy bands are highly spectrally coherent. We compare model predictions directly to X-ray data from the narrow line Seyfert 1 galaxy NGC 4051 and the black hole X-ray binary (BHXRB) Cyg X-1 in its high/soft state, and we show that this general scheme can reproduce simultaneously the time lags and energy-dependence of the PSD. C1 Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Arevalo, P (reprint author), Max Planck Inst Extraterr Phys, Postfach 1312, D-85741 Garching, Germany. EM parevalo@mpe.mpg.de NR 37 TC 149 Z9 149 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 1 PY 2006 VL 367 IS 2 BP 801 EP 814 DI 10.1111/j.1365-2966.2006.09989.x PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022OG UT WOS:000236064800026 ER PT J AU Gonzalez-Cuevas, JA Refaat, TF Abedin, MN Elsayed-Ali, HE AF Gonzalez-Cuevas, Juan A. Refaat, Tamer F. Abedin, M. Nurul Elsayed-Ali, Hani E. TI Modeling of the temperature-dependent spectral response of In1-XGaXSb infrared photodetectors SO OPTICAL ENGINEERING LA English DT Article DE photodetectors; spectral response; temperature effect; optical properties; electrical properties; InGaSb ID OPTICAL DISPERSION-RELATIONS; AUGER RECOMBINATION; DIELECTRIC FUNCTION; MATERIAL PARAMETERS; GAAS; GAP; SEMICONDUCTORS; GASB; INP; MOBILITY AB A model of the spectral responsivity of In1-xGaxSb p-n junction infrared photodetectors is developed. This model is based on calculations of the photogenerated and diffusion currents in the device. Expressions for the carrier mobilities, absorption coefficient, and normal-incidence reflectivity as a function of temperature are derived from extensions made to Adachi and Caughey-Thomas models. Contributions from the Auger recombination mechanism, which increase with a rise in temperature, are also considered. The responsivity is evaluated for different doping levels, diffusion depths, operating temperatures, and photon energies. Parameters calculated from the model are compared with available experimental data, and good agreement is obtained. These theoretical calculations help us to better understand the electro-optical behavior of In1-xGaxSb photodetectors, and can be utilized for performance enhancement through optimization of the device structure. (c) 2006 Society of Photo-Optical Instrumentation Engineers. C1 Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. NASA, Langley Res Ctr, Sci & Technol Corp, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Pass Sensor Syst Branch, Hampton, VA 23681 USA. RP Gonzalez-Cuevas, JA (reprint author), Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. RI GONZALEZ-FRAGA, JOSE/B-3487-2008; Alvarez-Borrego, Josue/J-6176-2016; OI GONZALEZ-FRAGA, JOSE/0000-0003-2144-8835; Alvarez-Borrego, Josue/0000-0002-4038-3435; Kober, Vitaly/0000-0002-9374-9883 NR 34 TC 52 Z9 52 U1 0 U2 1 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 EI 1560-2303 J9 OPT ENG JI Opt. Eng. PD APR PY 2006 VL 45 IS 4 AR 044001 DI 10.1117/1.2192772 PG 8 WC Optics SC Optics GA 043SP UT WOS:000237622200018 ER PT J AU Pishnyak, O Golovin, A Kreminska, L Pouch, JJ Miranda, FA Winker, BK Lavrentovich, OD AF Pishnyak, O Golovin, A Kreminska, L Pouch, JJ Miranda, FA Winker, BK Lavrentovich, OD TI Smectic-A-filled birefringent elements and fast switching twisted dual-frequency nematic cells used for digital light deflection SO OPTICAL ENGINEERING LA English DT Article DE beam deflector; smectic A; polarization rotator; birefringent prism ID LIQUID-CRYSTAL; BEAM DEFLECTOR; CHOLESTERIC GRATINGS; DRIVEN; TRANSITION; EFFICIENT; BEHAVIOR; PATTERN; ARRAY AB We describe the application of smectic A (SmA) liquid crystals for beam deflection. SmA materials can be used in digital beam deflectors (DBDs) as fillers for passive birefringent prisms. SmA prisms have high birefringence and can be constructed in a variety of shapes, including single prisms and prismatic blazed gratings of different angles and profiles. We address the challenges of uniform alignment of SmA, such as elimination of focal conic domains. Fast rotation of the incident light polarization in DBDs is achieved by an electrically switched 90-deg twisted nematic (TN) cell. (c) 2006 Society of Photo-Optical Instrumentation Engineers. C1 Kent State Univ, Chem Phys Interdisciplinary Program, Kent, OH 44242 USA. Kent State Univ, Inst Liquid Crystal, Kent, OH 44242 USA. Truman State Univ, Kirksville, MO 63501 USA. NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. Rockwell Sci Co LLC, Thousand Oaks, CA 91360 USA. RP Pishnyak, O (reprint author), Kent State Univ, Chem Phys Interdisciplinary Program, POB 5190, Kent, OH 44242 USA. EM odl@lci.kent.edu RI Lavrentovich, Oleg/B-4996-2011 NR 42 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD APR PY 2006 VL 45 IS 4 AR 044002 DI 10.1117/1.2192520 PG 9 WC Optics SC Optics GA 043SP UT WOS:000237622200019 ER PT J AU Spedalieri, FM AF Spedalieri, FM TI Quantum key distribution without reference frame alignment: Exploiting photon orbital angular momentum SO OPTICS COMMUNICATIONS LA English DT Article ID FRACTIONAL FOURIER-TRANSFORM; FREE-SPACE; MODE CONVERTERS; GAUSS-HERMITE; LIGHT; BEAMS; STATES AB We present a new implementation of the BB84 quantum key distribution (QKD) protocol that employs a d-dimensional Hilbert space spanned by spatial modes of the propagating beam that have a definite value of orbital angular momentum. Each photon carries logd bits of information, increasing the key generation rate of the protocol. The states used in the transmission part of the protocol are invariant under rotations about the propagation direction, making this implementation independent of the alignment between the reference frames of the sender and receiver. and hence appealing for free space QKD. The protocol still works when these reference frames rotate with respect to each other. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, 4800 Oak Grove Dr,Mail Stop 126-347, Pasadena, CA 91109 USA. EM Federico.Spedalieri@jpl.nasa.gov NR 32 TC 18 Z9 18 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 EI 1873-0310 J9 OPT COMMUN JI Opt. Commun. PD APR 1 PY 2006 VL 260 IS 1 BP 340 EP 346 DI 10.1016/j.optcom.2005.10.001 PG 7 WC Optics SC Optics GA 028PJ UT WOS:000236500000058 ER PT J AU Sztul, HI Alfano, RR AF Sztul, HI Alfano, RR TI Double-slit interference with Laguerre-Gaussian beams SO OPTICS LETTERS LA English DT Article ID ORBITAL ANGULAR-MOMENTUM; LASER MODES; LIGHT; DIFFRACTION AB The interference of Laguerre-Gaussian beams carrying orbital angular momentum was demonstrated in Young's double-slit geometry. Double-slit interference is shown to be affected by the azimuthal phase dependence of a Laguerre-Gaussian beam. This interference provides new insight into the helical phase structure of the Laguerre-Gaussian beam and has potential applications for measuring the orbital angular momentum of an arbitrary wavefront. (c) 2006 Optical Society of America. C1 CUNY City Coll, Dept Phys, NASA, Ctr Opt Sensing & Imaging,Inst Ultrafast Spect &, New York, NY 10031 USA. CUNY, Grad Sch, New York, NY 10031 USA. RP Sztul, HI (reprint author), CUNY City Coll, Dept Phys, NASA, Ctr Opt Sensing & Imaging,Inst Ultrafast Spect &, 138th St Convent Ave, New York, NY 10031 USA. EM hsztul@gc.cuny.edu NR 14 TC 93 Z9 101 U1 7 U2 32 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD APR 1 PY 2006 VL 31 IS 7 BP 999 EP 1001 DI 10.1364/OL.31.000999 PG 3 WC Optics SC Optics GA 026QV UT WOS:000236358100049 PM 16602188 ER PT J AU Guillaume, A Dowling, JP AF Guillaume, A Dowling, JP TI Heisenberg-limited measurements with superconducting circuits SO PHYSICAL REVIEW A LA English DT Article ID TRAPPED IONS; ENTANGLEMENT; STATE AB We describe an assembly of N superconducting qubits contained in a single- mode cavity. In the dispersive regime, the correlation between the cavity field and each qubit results in an effective interaction between qubits that can be used to dynamically generate maximally entangled states. With only collective manipulations, we show how to create maximally entangled quantum states and how to use these states to reach the Heisenberg limit in the determination of the qubit bias control parameter (gate charge for charge qubits, external magnetic flux for rf-superconducting quantum interference devices). C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Louisiana State Univ, Dept Phys & Astron, Hearne Inst Theoret Phys, Baton Rouge, LA 70803 USA. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Texas A&M Univ, Inst Quantum Studies, College Stn, TX 77843 USA. RP Guillaume, A (reprint author), CALTECH, Jet Prop Lab, Mail Stop 302-306,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Alexandre.Guillaume@jpl.nasa.gov RI DOWLING, JONATHAN/L-2749-2013 NR 18 TC 1 Z9 1 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 2006 VL 73 IS 4 AR 040304 DI 10.1103/PhysRevA.73.040304 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 037LG UT WOS:000237147700004 ER PT J AU Browning, CD Ivancic, TM Bowman, RC Conradi, MS AF Browning, CD Ivancic, TM Bowman, RC Conradi, MS TI Comparison of spin relaxation in the metal-hydrogen systems ZrNiHx and ZrNiDx SO PHYSICAL REVIEW B LA English DT Article ID INTERSTITIAL SITE OCCUPATION; HYDRIDE PHASE GROWTH; THERMODYNAMIC CHARACTERIZATION; TRANSLATIONAL DIFFUSION; INTERMETALLIC COMPOUNDS; H SYSTEM; SOLIDS; DEGRADATION; ZRNI-H-2 AB Relaxation studies of the intermetallics ZrNiHx and ZrNiDx were performed using hydrogen and deuterium NMR in the beta (x similar or equal to 0.85) and gamma phases (x similar or equal to 2.6 and 3.0). Correlation times for atomic diffusion in the hydride were determined based on the temperature dependence of spin-lattice and spin-spin relaxation times. The hydrogen motion is shown to be thermally activated over the temperature range 300-550 K, and the activation energies for diffusion are determined. The deuterium NMR spectra exhibit incomplete line narrowing with temperature, indicating that the average electric field gradient is not zero when averaged over the deuterium atom sites of these noncubic unit cells. The temperatures of minima in T-1 and T-2 for the deuterides indicate that the motion rates are similar for the D and H systems. However, the activation energies taken from the temperature dependencies of the deuterides' T-1 and T-2 are much smaller than for the hydrides, indicating the deuteride relaxation rates have additional contributions. The spectrum of ZrNiD1.87 reveals a coexistence of two phases, in agreement with the phase diagram. C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91190 USA. RP Browning, CD (reprint author), Washington Univ, Dept Phys, CB 1105,1 Brookings Dr, St Louis, MO 63130 USA. EM msc@wuphys.wustl.edu OI Bowman, Robert/0000-0002-2114-1713 NR 39 TC 3 Z9 3 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR PY 2006 VL 73 IS 13 AR 134113 DI 10.1103/PhysRevB.73.134113 PG 11 WC Physics, Condensed Matter SC Physics GA 037NN UT WOS:000237153800042 ER PT J AU Malkova, N Ning, CZ AF Malkova, N Ning, CZ TI Light propagation through a sharp-bend coupled-cavity waveguide in a two-dimensional photonic crystal SO PHYSICAL REVIEW B LA English DT Article ID TRANSMISSION AB We investigate light propagation through a coupled-defect waveguide with a 45 degrees sharp bend in a two-dimensional photonic crystal analytically and numerically. The waveguide mode is the degenerate defect state of a square lattice. The transmission through such a structure drops by two orders of magnitude if a 45 degrees bend is introduced. We show that, by properly distorting the lattice around each defect, the splitting of the degenerate defect state allows resonant transmission through the bend, leading to a two orders of magnitude increase in transmission through the bend waveguide. Several applications of such waveguides are discussed including dynamical directional switching and dynamic light trapping and releasing. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Malkova, N (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM nmalkova@mail.arc.nasa.gov; cning@mail.arc.nasa.gov RI Ning, C. Z./D-4699-2009 OI Ning, C. Z./0000-0003-4583-8889 NR 17 TC 1 Z9 1 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR PY 2006 VL 73 IS 15 AR 155101 DI 10.1103/PhysRevB.73.155101 PG 7 WC Physics, Condensed Matter SC Physics GA 037OA UT WOS:000237155100025 ER PT J AU Samara, GA Barnes, CE AF Samara, GA Barnes, CE TI Pressure dependence of the configurational bistability and deep electronic levels of the MFe center in InP SO PHYSICAL REVIEW B LA English DT Article ID DEFORMATION POTENTIALS; BISTABLE DEFECT; NATIVE DEFECTS; DOPED SILICON; SEMICONDUCTORS; RELAXATION; VACANCIES; MODEL; EDGE AB The influence of hydrostatic pressure on the structural bistability and electronic properties of the processing-induced MFe center in Fe-doped n-type InP was investigated. Earlier work has shown that, when occupied by electrons, the center can be reversibly placed in either of two configurations, termed A and B, by the proper choice of electric biasing conditions and temperature. Pressure strongly modifies the energetics and kinetics of the various electronic transitions and of the transformations associated with the center. The activation volumes (Delta V-*) for these processes were determined. In the absence of barriers to electron capture, or for small barriers, Delta V-* can be interpreted as the breathing mode relaxation associated with electron emission or capture. At pressures >= 8 kbar, the center exists only in the A configuration regardless of bias conditions, because at these pressures the energetics and kinetics of the various processes have changed so much as to always favor the A configuration. It is also shown that, whereas the A -><- B transformations are charge state controlled at 1 bar, this is not the case at high pressure where the transformations can be brought about without electron emission or hole capture. Earlier tentative atomic models for the center are discussed, and it is shown that some features of one of the models including the signs of the breathing mode relaxations associated with the various electron emissions are consistent with the experimental results, but issues remain. The results are also found to be generally consistent with first-principles calculations on defects in InP, but it is emphasized that whereas these calculations are for simple defects, the defects associated with the MFe center are more complex. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Samara, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD APR PY 2006 VL 73 IS 15 AR 155206 DI 10.1103/PhysRevB.73.155206 PG 11 WC Physics, Condensed Matter SC Physics GA 037OA UT WOS:000237155100050 ER PT J AU Kobayashi, H AF Kobayashi, H TI Large eddy simulation of magnetohydrodynamic turbulent channel flows with local subgrid-scale model based on coherent structures SO PHYSICS OF FLUIDS LA English DT Article ID MAGNETIC REYNOLDS-NUMBER; DIRECT-NUMERICAL-SIMULATION; INCOMPRESSIBLE-FLOW; MIXING LAYER; SHEAR FLOWS; FIELD; FLUID; CLOSURE AB For turbulent channel flows with a uniform magnetic field perpendicular to insulated walls, the performance of the coherent structure Smagorinsky model (CSM) is investigated in comparison to the Smagorinsky model (SM) and the dynamic Smagorinsky model (DSM). The Lorentz force acts against a streamwise flow. The effect of the Hartmann flattening leads to an increase in the wall shear stress, so that the skin friction coefficient increases. In contrast, the turbulence suppression by the magnetic field results in a decrease of the Reynolds shear stress near the wall, so that the skin friction coefficient decreases. As the magnetic field increases, a turbulent magnetohydrodynamic (MHD) flow transits to a laminar MHD flow at a critical Hartmann number. The CSM predicts a higher transition Hartmann number than the DSM and SM, because the model parameter of the CSM is locally determined based on coherent structures and the fluctuations are reflected in the shear stress. On the other hand, the model parameter of the DSM is averaged in the homogeneous directions, so that the shear stress is somewhat underestimated for the subcritical Hartmann number. The SM with a model constant and a wall damping function of the Van Driest type reproduces the laminar MHD flow at the lowest transition Hartmann number, because the model parameter (which does not change in the magnetic field) provides significant energy dissipation. Moreover, the CSM and DSM can reproduce properly the laminar MHD flow at high Hartmann number, because the model parameters of the CSM and DSM are drastically damped near the wall and the Reynolds shear stresses are suppressed to zero. The skin friction coefficients predicted by the CSM and DSM agree with the "two-dimensional" laminar solution, whereas the SM gives higher values than the laminar solution. The coherent structures become large and align themselves along the magnetic field in the transition to the laminar MHD flow. (C) 2006 American Institute of Physics. C1 Stanford Univ, NASA, Ames Res Ctr, Ctr Turbulence Res, Stanford, CA 94305 USA. Keio Univ, Dept Phys, Kouhoku Ku, Yokohama, Kanagawa 2238521, Japan. RP Kobayashi, H (reprint author), Stanford Univ, NASA, Ames Res Ctr, Ctr Turbulence Res, Stanford, CA 94305 USA. EM hkobayas@phys-h.keio.ac.jp NR 29 TC 25 Z9 25 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD APR PY 2006 VL 18 IS 4 AR 045107 DI 10.1063/1.2194967 PG 11 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 037HE UT WOS:000237136900039 ER PT J AU Shariff, K Leonard, A Ferziger, JH AF Shariff, K Leonard, A Ferziger, JH TI Dynamical systems analysis of fluid transport in time-periodic vortex ring flows SO PHYSICS OF FLUIDS LA English DT Article ID MUTUAL SLIP-THROUGH; COHERENT STRUCTURES; CHAOTIC ADVECTION; STOKES-FLOW; PAIR; INSTABILITY; TURBULENCE; MANIFOLDS; VORTICES; VELOCITY AB It is known that the stable and unstable manifolds of dynamical systems theory provide a powerful tool for understanding Lagrangian aspects of time-periodic flows. In this work we consider two time-periodic vortex ring flows. The first is a vortex ring with an elliptical core. The manifolds provide information about entrainment and detrainment of irrotational fluid into and out of the volume transported with the ring. The likeness of the manifolds with features observed in flow visualization experiments of turbulent vortex rings suggests that a similar process might be at play. However, what precise modes of unsteadiness are responsible for stirring in a turbulent vortex ring is left as an open question. The second situation is that of two leapfrogging rings. The unstable manifold shows striking agreement with even the fine features of smoke visualization photographs, suggesting that fluid elements in the vicinity of the manifold are drawn out along it and begin to reveal its structure. We suggest that interpretations of these photographs that argue for complex vorticity dynamics ought to be reconsidered. Recently, theoretical and computational tools have been developed to locate structures analogous to stable and unstable manifolds in aperiodic, or finite-time systems. The usefulness of these analogs is demonstrated, using vortex ring flows as an example, in the paper by Shadden, Dabiri, and Marsden [Phys. Fluids 18, 047105 (2006)]. (C) 2006 American Institute of Physics. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. CALTECH, Pasadena, CA 91125 USA. Stanford Univ, Stanford, CA 94305 USA. RP Shariff, K (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM kshariff@mail.arc.nasa.gov OI Shariff, Karim/0000-0002-7256-2497 NR 39 TC 12 Z9 12 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD APR PY 2006 VL 18 IS 4 AR 047104 DI 10.1063/1.2189867 PG 11 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 037HE UT WOS:000237136900048 ER PT J AU Zuckerwar, AJ Ash, RL AF Zuckerwar, AJ Ash, RL TI Variational approach to the volume viscosity of fluids SO PHYSICS OF FLUIDS LA English DT Article ID BULK VISCOSITY; RELAXATION AB The variational principle of Hamilton is applied to develop an analytical formulation to describe the volume viscosity in fluids. The procedure described here differs from those used in the past in that a dissipative process is represented by the chemical affinity and progress variable (sometimes called "order parameter") of a reacting species. These state variables appear in the variational integral in two places: first, in the expression for the internal energy, and second, in a subsidiary condition accounting for the conservation of the reacting species. As a result of the variational procedure, two dissipative terms appear in the Navier-Stokes equation. The first is the traditional volume viscosity term, proportional to the dilatational component of velocity; the second term is proportional to the material time derivative of the pressure gradient. Values of the respective volume viscosity coefficients are determined by applying the resulting volume-viscous Navier-Stokes equation to the case of acoustical propagation and then comparing expressions for the dispersion and absorption of sound. The formulation includes the special case of equilibration of the translational degrees of freedom. As examples, values are tabulated for dry and humid air, argon, and sea water. (C) 2006 American Institute of Physics. C1 Old Dominion Univ, Dept Aerosp Engn, Norfolk, VA 23508 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Zuckerwar, AJ (reprint author), Old Dominion Univ, Dept Aerosp Engn, Norfolk, VA 23508 USA. EM a.j.zuckerwar@larc.nasa.gov; rash@odu.edu NR 30 TC 13 Z9 13 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD APR PY 2006 VL 18 IS 4 AR 047101 DI 10.1063/1.2180780 PG 10 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 037HE UT WOS:000237136900045 ER PT J AU Trotignon, JG Mazelle, C Bertucci, C Acuna, MH AF Trotignon, JG Mazelle, C Bertucci, C Acuna, MH TI Martian shock and magnetic pile-up boundary positions and shapes determined from the Phobos 2 and Mars Global Surveyor data sets SO PLANETARY AND SPACE SCIENCE LA English DT Article DE Planet Mars; bow shock position and shape; magnetic pile-up boundary position and shape; Phobos 2 mission; Mars Global Surveyor mission ID SOLAR-WIND INTERACTION; PLASMA-WAVE SYSTEM; FIELD DRAPING ENHANCEMENT; ION COMPOSITION BOUNDARY; BOW SHOCK; TERRESTRIAL PLANETS; VENUS; MISSION; MAGNETOSPHERE; ENVIRONMENT AB A great many Martian bow shock and magnetic pile-up boundary crossings have been identified in the Phobos 2 and Mars Global Surveyor, MGS, data. From these observations the positions and shapes of the bow shock and magnetic pile-up boundary, MPB, have been derived and modelled, using curve-fitting techniques. The models thus derived separately from the Phobos 2 and MGS data sets do not differ drastically, despite the different time and space data coverages. The purpose of the paper is therefore to show the results obtained from the mixing of the Phobos 2 and MGS data bases and to compare the derived bow shock and MPB models with the ones obtained previously. The underlying objective was to see whether it was possible to determine improved bow shock and MPB models or not. The answer is definitely yes, and particularly for the MPB, thanks to the complementary nature of the observations. The boundaries crossed close to the subsolar direction or mostly far downstream by Phobos 2 indeed allow a better coverage of the Martian space environment to be considered. Nevertheless, in order to reduce the domination of the overabundant MGS data set and/or the crossings that are close to Mars (x > -4 R-M, i.e. x > -13 562 km) weighting factors have been introduced. (c) 2006 Elsevier Ltd. All rights reserved. C1 Univ Orleans, CNRS, Lab Phys & Chim Environm, F-45071 Orleans 02, France. Univ Toulouse 3, CNRS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Space & Atmospher Phys Grp, London SW7 2BZ, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Trotignon, JG (reprint author), Univ Orleans, CNRS, Lab Phys & Chim Environm, 3A Ave Rech Sci, F-45071 Orleans 02, France. EM Jean-Gabriel.Trotignon@cnrs-orleans.fr OI Bertucci, Cesar/0000-0002-2540-5384 NR 41 TC 55 Z9 55 U1 2 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR PY 2006 VL 54 IS 4 BP 357 EP 369 DI 10.1016/j.pss.2006.01.003 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 033DW UT WOS:000236827800005 ER PT J AU Berthelier, JJ Godefroy, M Leblanc, F Malingre, M Menvielle, M Lagoutte, D Brochot, JY Colin, F Elie, F Legendre, C Zamora, P Benoist, D Chapuis, Y Artru, J Pfaff, R AF Berthelier, J. J. Godefroy, M. Leblanc, F. Malingre, M. Menvielle, M. Lagoutte, D. Brochot, J. Y. Colin, F. Elie, F. Legendre, C. Zamora, P. Benoist, D. Chapuis, Y. Artru, J. Pfaff, R. TI ICE, the electric field experiment on DEMETER SO PLANETARY AND SPACE SCIENCE LA English DT Article DE DC/AC electric field sensors; ionospheric plasma waves; ionospheric turbulence; ionospheric effects of seismsic activity ID PERIODIC VLF EMISSIONS; EQUATORIAL SPREAD-F; ELECTROMAGNETIC EMISSIONS; MAGNETIC PULSATIONS; KOBE EARTHQUAKE; MAGNETOSPHERE; IONOSPHERE; SATELLITE; ANOMALIES; STROKES AB The objective of the ICE (Instrument Champ Electrique) experiment on board DEMETER is to provide a nearly continuous survey of the electromagnetic and/or electrostatic waves that may arise from the coupling of seismic activity with the upper atmosphere and ionosphere. To this aim it makes use of 4 spherical electrodes with embedded preamplifiers that are deployed by stacer booms at approximately 4 in from the satellite. Measurements are made over a wide frequency range from DC to 3.175 MHz, subdivided in the signal processing unit in four frequency channels DC/ULF, ELF, VLF and HF. Three axis measurements are available in the DC/ULF range for all modes of operation of DEMETER and in the ELF range in the DEMETER Burst modes. In the VLF and HF ranges and in ELF during DEMETER Survey modes only one axis of measurement is available that can be selected by telecommand. We present in this paper a general description of the instrument and its modes of operation and in-flight performances. The sensitivity is similar to 0.1-0.2 mu V/mHz(1/2) from similar to 100 Hz through the HF range and the dynamical range is > 80 dB in ELF and VLF and about 42 dB in HF. In order to illustrate the instrument capabilities, we briefly describe a number of observations from the first months of operation in various regions along the orbit from the equator to high latitudes. (c) 2006 Elsevier Ltd. All rights reserved. C1 IPSL, CETP, F-94107 St Maur, France. LPCE, F-45071 Orleans 2, France. Observ Nancay, F-18330 Nancay, France. CALTECH, JPL, Pasadena, CA 91125 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Berthelier, JJ (reprint author), IPSL, CETP, 4 Ave Neptune, F-94107 St Maur, France. EM Jean-Jacques.berthelier@cetp.ipsl.fr RI Pfaff, Robert/F-5703-2012 OI Pfaff, Robert/0000-0002-4881-9715 NR 39 TC 167 Z9 195 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR PY 2006 VL 54 IS 5 BP 456 EP 471 DI 10.1016/j.pss.2005.10.016 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 045WI UT WOS:000237773000005 ER PT J AU Berthelier, JJ Godefroy, M Leblanc, F Seran, E Peschard, D Gilbert, P Artru, J AF Berthelier, JJ Godefroy, M Leblanc, F Seran, E Peschard, D Gilbert, P Artru, J TI IAP, the thermal plasma analyzer on DEMETER SO PLANETARY AND SPACE SCIENCE LA English DT Article DE retarding potential analyzers; ionosphere; ionospheric thermal plasma measurements; ionospheric effects of seismic activity ID TRAVELING IONOSPHERIC DISTURBANCES; ATMOSPHERIC GRAVITY-WAVES; EQUATORIAL SPREAD-F; RADAR OBSERVATIONS; EARTHQUAKE; IRREGULARITIES; BUBBLES; PERTURBATIONS; OSCILLATIONS; GENERATION AB The Instrument d'Analyse du Plasma (IAP) on board DEMETER provides a nearly continuous survey of the main parameters of the thermal ion population with two main objectives. The first one is to detect disturbances in the ionosphere that may arise from the coupling between seismic events on the ground and the upper atmosphere and ionosphere. The second objective is to provide with a sufficient time resolution the ionospheric parameters such as the plasma density and the ion composition that are needed to analyze the plasma wave data from the ICE and IMSC experiments. In addition the IAP observations will allow to build a large database that call be used in the frame of space weather studies, for example to analyze the dynamics of the mid-latitude ionosphere in response to magnetic storms. The instrument makes use of two analyzers to measure: (i) the energy distribution of the rammed ions and (ii) the direction of their bulk velocity. The basic principle of this well-known technique of measurement [Hanson, W.B., Heelis, R.A., 1975. Techniques for measuring bulk gas motions from satellites. Space Sci. Instrum. 1, 493-524] is recalled in Section 3 completed by a description of the analyzers with their associated electronics and of the modes of operation of the instrument. Following a brief presentation of the data analysis algorithm and its application to real data, some examples of observations made during the first months of operation of the satellite are displayed in the last section and illustrate the IAP capabilities. (c) 2006 Elsevier Ltd. All rights reserved. C1 IPSL, CETP, F-94100 St Maur, France. CALTECH, JPL, Pasadena, CA 91125 USA. RP Berthelier, JJ (reprint author), IPSL, CETP, 4 Ave Neptune, F-94100 St Maur, France. EM Jean-Jacques.berthelier@cetp.ipsl.fr NR 45 TC 73 Z9 89 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD APR PY 2006 VL 54 IS 5 BP 487 EP 501 DI 10.1016/j.pss.2005.10.018 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 045WI UT WOS:000237773000007 ER PT J AU Parker, PA Kowalski, SA Vining, GG AF Parker, PA Kowalski, SA Vining, GG TI Classes of split-plot response surface designs for equivalent estimation SO QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL LA English DT Article DE restricted randomization; split-plot designs; equivalent estimation; Box-Behnken design; equiradial design; small composite design AB When planning all experimental investigation, we are frequently faced with factors that are difficult or time consuming to manipulate, thereby making complete randomization impractical. A split-plot structure differentiates between the experimental units associated with these hard-to-change factors and those that are relatively easy-to-change. Furthermore, it provides all efficient strategy that integrates the restrictions imposed by the experimental apparatus into the design structure. In this paper, several industrial and scientific examples are presented to highlight design considerations when a restriction oil randomization is encountered. We propose classes of split-plot response designs that provide all intuitive and natural extension from the completely randomized context. For these designs, the ordinary least-squares estimates of the model are equivalent to the generalized least-squares estimates. This property provides best linear unbiased estimators and simplifies model estimation. The design conditions that provide equivalent estimation are presented and lead to design construction strategies to transform completely randomized Box-Behnken, equiradial and small composite designs into a split-plot structure. Published in 2006 by John Wiley & Sons, Ltd. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Minitab Inc, State Coll, PA 16801 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. RP Parker, PA (reprint author), NASA, Langley Res Ctr, Mail Stop 238, Hampton, VA 23681 USA. EM peter.a.parker@larc.nasa.gov NR 21 TC 18 Z9 20 U1 0 U2 5 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0748-8017 J9 QUAL RELIAB ENG INT JI Qual. Reliab. Eng. Int. PD APR PY 2006 VL 22 IS 3 BP 291 EP 305 DI 10.1002/qre.771 PG 15 WC Engineering, Multidisciplinary; Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 040FL UT WOS:000237364300006 ER PT J AU Johnston, JC McCann, RS AF Johnston, JC McCann, RS TI On the locus of dual-task interference: Is there a bottleneck at the stimulus classification stage? SO QUARTERLY JOURNAL OF EXPERIMENTAL PSYCHOLOGY LA English DT Article ID PSYCHOLOGICAL REFRACTORY-PERIOD; ATTENTIONAL BLINK; CHRONOMETRIC EVIDENCE; CENTRAL POSTPONEMENT; DIVIDED ATTENTION; OVERLAPPING TASKS; PERFORMANCE; MODEL; FMRI; LOCALIZATION AB Recent studies have provided evidence that dual-task interference is typically caused by a single-channel bottleneck, but the processing locus of the bottleneck has yet to be pinned down. A bottleneck locus at the response-selection stage is widely advocated, but an earlier locus would be consistent with most previous evidence. Four new experiments used the "locus of slack" method to investigate whether the stages postponed by the central bottleneck include stimulus classification, a very late stage of perceptual processing. The experiments varied stimulus classification difficulty for two different analogueue perceptual judgements. Experiment 1 found only modest absorption into slack for the difficulty of a spatial position judgement. Experiments 2-4 found virtually no absorption into slack for the difficulty of a box-width judgement. These results support a bottleneck locus beginning at or before the stage of stimulus classification and hence prior to the stage of response selection. Other evidence, however, leaves no doubt that response selection is also subject to bottleneck postponement. Two architectures are discussed that can account parsimoniously for both old and new results. One posits a single bottleneck resulting from a unified CPU-like central processor; the other posits multiple bottlenecks resulting from multiple processors accomplishing different substages of central processing. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Johnston, JC (reprint author), NASA, Ames Res Ctr, MS 262-4, Moffett Field, CA 94035 USA. EM jcjohnston@mail.arc.nasa.gov NR 61 TC 24 Z9 24 U1 1 U2 2 PU PSYCHOLOGY PRESS PI HOVE PA 27 CHURCH RD, HOVE BN3 2FA, EAST SUSSEX, ENGLAND SN 1747-0218 J9 Q J EXP PSYCHOL JI Q. J. Exp. Psychol. PD APR PY 2006 VL 59 IS 4 BP 694 EP 719 DI 10.1080/02724980543000015 PG 26 WC Psychology, Biological; Physiology; Psychology; Psychology, Experimental SC Psychology; Physiology GA 036IE UT WOS:000237064000005 PM 16707358 ER PT J AU Richmond, RC AF Richmond, RC TI Edward Lawrence Powers, Jr. (1915-2005) - In memoriam SO RADIATION RESEARCH LA English DT Biographical-Item C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Richmond, RC (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD APR PY 2006 VL 165 IS 4 BP 492 EP 494 DI 10.1667/RR3517.1 PG 3 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 028MN UT WOS:000236491800015 ER PT J AU Yeniay, O Unal, R Lepsch, RA AF Yeniay, O Unal, R Lepsch, RA TI Using dual response surfaces to reduce variability in launch vehicle design: A case study SO RELIABILITY ENGINEERING & SYSTEM SAFETY LA English DT Article DE uncertainty; response surface methods; D-Optimal designs; optimization ID OPTIMIZATION AB Space transportation system conceptual design is a multi disciplinary process containing considerable element of risk. Uncertainties from one engineering discipline may propagate to another through linking parameters and the final system output may have an accumulation of risk. This may lead to significant deviations from expected performance. An estimate of variability or design risk therefore becomes essential for a robust design. This study utilizes the dual response surface approach to quantify variability in critical performance characteristics during conceptual design phase of a launch vehicle. Using design of experiments methods and disciplinary design analysis codes, dual response surfaces are constructed for the mean and standard deviation to quantify variability in vehicle weight and sizing analysis. Next, an optimum solution is sought to minimize variability subject to a constraint on mean weight. In this application, the dual response surface approach lead to quantifying and minimizing variability without much increase in design effort. (c) 2005 Elsevier Ltd. All rights reserved. C1 Old Dominion Univ, Engn Management & Syst Engn Dept, Norfolk, VA 23693 USA. Univ Hacettepe, Dept Stat, TR-06100 Ankara, Turkey. NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. RP Unal, R (reprint author), Old Dominion Univ, Engn Management & Syst Engn Dept, Norfolk, VA 23693 USA. EM runal@odu.edu RI Yeniay, Ozgur/E-6647-2013 NR 26 TC 15 Z9 19 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0951-8320 J9 RELIAB ENG SYST SAFE JI Reliab. Eng. Syst. Saf. PD APR PY 2006 VL 91 IS 4 BP 407 EP 412 DI 10.1016/j.ress.2005.02.007 PG 6 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 014UT UT WOS:000235506500004 ER EF