FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Ellis, AT Lessard, MR Bartel, P Disbrow, M Riley, P AF Ellis, AT Lessard, MR Bartel, P Disbrow, M Riley, P TI Despun rocket borne imager: Design aspects of a space based optical imaging instrument for auroral studies SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB Imaging the aurora from space is scientifically rewarding since understanding the fluctuations in conjunction with other parameters measured along the magnetic field line of interest can resolve ambiguities regarding the nature of the emissions as well as provide a context for the emissions. Typical payloads launched on sounding rockets for auroral studies are spin stabilized, which imply that standard imaging techniques cannot be used due to severe blurring. The despun rocket borne imager is a simple instrumentation concept that uses a Dove prism to counter the rotation effects of the spinning platform and thus produce images without blurring. This technique has been applied to two instruments flown on sounding rockets with varying optical properties needed to address specific scientific queries. This article discusses the design of both of these instruments and includes the necessary considerations for a generic instrument for future projects. (c) 2006 American Institute of Physics. C1 Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. Goodrich Corp, Chelmsford, MA 01824 USA. NASA, Wallops Flight Facil, Wallops Isl, VA 23337 USA. RP Ellis, AT (reprint author), Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 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 APR PY 2006 VL 77 IS 4 AR 045112 DI 10.1063/1.2195102 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 037HA UT WOS:000237136500058 ER PT J AU Holman, GD AF Holman, GD TI The mysterious origins of solar flares SO SCIENTIFIC AMERICAN LA English DT Article C1 NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. RP Holman, GD (reprint author), NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. RI Holman, Gordon/C-9548-2012 NR 2 TC 3 Z9 3 U1 1 U2 5 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD APR PY 2006 VL 294 IS 4 BP 38 EP 45 PG 8 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 021UN UT WOS:000236011500026 PM 16596878 ER PT J AU Lach, CL Turner, TL Taminger, KM Shenoy, RN AF Lach, CL Turner, TL Taminger, KM Shenoy, RN TI Post-processed Nitinol actuator structure-property study SO SMART MATERIALS & STRUCTURES LA English DT Article ID SHAPE-MEMORY ALLOY; SMA HYBRID COMPOSITES; PHASE; TRANSFORMATION; STRESS AB Previous NASA work has included fabrication and modeling of hybrid composite (HC) specimens with embedded Nitinol ribbon actuators and thermornechanical testing of the constituents. The Nitinol tensile behavior depended significantly on the thermornechanical condition (TMC). A Nitinol microstructure/mechanical property characterization was conducted on four TMCs. Differential scanning calorimetry and x-ray diffraction were used to rationalize the microstructures present. Tensile tests determined the effect of TMC on the Nitinol tensile behavior and stress state of the microstructure. Three TMCs showed typical shape memory behavior. The TMC that simulated the HC autoclave process on the actuator resulted in an irreversible microstructure. The microstructural constituents and their stress states probably govern the Nitinol stress-strain behavior. The critical stress to achieve an initial stress plateau was dependent on the amount and stress state of R-phase present in the initial microstructure. Thus, prior TMC critically affects the Nitinol tensile behavior. Numerical model inputs Must therefore account for these effects on the Nitinol actuator. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. NASA, Met Thermal Struct Branch, Hampton, VA 23681 USA. NASA, Struct Acoust Branch, Hampton, VA 23681 USA. Lockheed Martin, Hampton, VA 23681 USA. RP Lach, CL (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. EM cynthia.l.lach@nasa.gov NR 16 TC 0 Z9 0 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD APR PY 2006 VL 15 IS 2 BP 485 EP 492 DI 10.1088/0964-1726/15/2/031 PG 8 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA 035PG UT WOS:000237013200031 ER PT J AU Brooks, DH Bewsher, D AF Brooks, DH Bewsher, D TI On deriving plasma velocity information from CDS/NIS observations: Application to the dynamics of blinkers SO SOLAR PHYSICS LA English DT Article ID CORONAL DIAGNOSTIC SPECTROMETER; TRANSITION REGION BLINKERS; DOMELESS SOLAR TELESCOPE; EXTREME-ULTRAVIOLET; QUIET-SUN; EXPLOSIVE EVENTS; BRIGHTENINGS; CDS AB Using standard instrument software and two independently developed data reduction and analysis procedures, we re-examine the accuracy of plasma velocity information derived from data obtained by the Solar and Heliospheric Observatory (SOHO)-Coronal Diagnostic Spectrometer (CDS). We discuss only the Ov 629 angstrom line data obtained by the Normal Incidence Spectrometer (NIS) and analyse a quiet Sun (QS) and active region (AR) dataset. Using the QS data, we demonstrate that the well-known North-South tilt in wavelength along the NIS slit varies significantly with time, which is not accounted for in the standard CDS correction procedures. In addition, when residual N - S trends exist in the data after processing, they may not be detected, nor removed, using the standard analysis software. This underscores the need for careful analysis of velocity results for individual datasets when using standard correction procedures. Furthermore, even when the results obtained by the two independent methods are well correlated (coefficients greater than 0.9), discrepancies in the values of the derived Doppler velocities can remain (95% within +/- 5 km s(-1)). Therefore, we apply the results to examine the velocities obtained for EUV blinkers by previous authors. It is found that a strong correlation exists in the patterns of variation of the blinker velocities (> 0.98), even though there may be differences in their magnitudes. That is, in a clear majority of cases, the methods agree that a blinker is red-shifted or blue-shifted, although the uncertainty in the absolute velocity may be large. C1 Kyoto Univ, Kwasan Observ, Yamashina Ku, Kyoto 6078471, Japan. Kyoto Univ, Hida Observ, Yamashina Ku, Kyoto 6078471, Japan. USN, EO Hulburt Ctr Space Res, Res Lab, Washington, DC 20375 USA. NASA, Res & Sci Support Dept, European Space Agcy, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Rutherford Appleton Lab, CCLRC, Space Sci & Technol Dept, Didcot OX11 0QX, Oxon, England. RP Brooks, DH (reprint author), Kyoto Univ, Kwasan Observ, Yamashina Ku, Kyoto 6078471, Japan. EM dhbrooks@ssd5.nrl.navy.mil OI Bewsher, Danielle/0000-0002-6351-5170 NR 17 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD APR PY 2006 VL 234 IS 2 BP 257 EP 272 DI 10.1007/s11207-006-0096-3 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 039SD UT WOS:000237326300004 ER PT J AU Reiner, MJ Kaiser, ML Fainberg, J Bougeret, JL AF Reiner, MJ Kaiser, ML Fainberg, J Bougeret, JL TI A highly circularly polarized solar radio emission component observed at hectometric wavelengths SO SOLAR PHYSICS LA English DT Article ID INTERPLANETARY MEDIUM; BURSTS; SPACECRAFT; CONTINUUM; DENSITY; WIND; MHZ AB We report here the observation of a rare solar radio event at hectometric wavelengths that was characterized by essentially 100% circularly polarized radiation and that was observed continuously for about six days, from May 17 to 23, 2002. This was the first time that a solar source with significantly polarized radiation was detected by the WAVES experiment on the Wind spacecraft. From May 19 to 22, the intense polarized radio emissions were characterized by quasi-periodic intensity variations with periods from one to two hours and with superposed drifting, narrowband, fine structures. The bandwidth of this radiation extended from about 400 kHz to 7 MHz, and the peak frequency of the frequency spectrum slowly decreased from 2 MHz to about 0.8 MHz over the course of four days. The radio source, at each frequency, was observed to slowly drift from east to west about the Sun, as viewed from the Earth and was estimated to lie between 26 and 82R(.) (R-. = 696 000 km). We speculate that this unusual event may represent an interplanetary manifestation of a moving type IV burst and discuss possible radio emission mechanisms. The ISEE-3 spacecraft may possibly have detected a similar event some 26 years ago. C1 Catholic Univ Amer, Greenbelt, MD 20770 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Observ Paris, Meudon, France. RP Reiner, MJ (reprint author), Catholic Univ Amer, Greenbelt, MD 20770 USA. EM michael.reiner@gsfc.nasa.gov NR 31 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 EI 1573-093X J9 SOL PHYS JI Sol. Phys. PD APR PY 2006 VL 234 IS 2 BP 301 EP 324 DI 10.1007/s11207-006-0087-4 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 039SD UT WOS:000237326300006 ER PT J AU Yu, B Meyyappan, M AF Yu, B Meyyappan, M TI Nanotechnology: Role in emerging nanoelectronics SO SOLID-STATE ELECTRONICS LA English DT Article; Proceedings Paper CT 35th European Solid-State Device Research Conference CY SEP 12-16, 2005 CL Grenoble, FRANCE SP imep, Leti, IEEE, European Device Soc, ST, LA METRO, CNRS, Soitec, isere, RhoneAlpes, Infineon Technol, Freescale, Atmel, Texas Instruments, Intel, Nanocmos, PHILIPS, Mentor Graph, SAMSUNG, Leti, Minatec, INP Grenoble, Minist Delegue Rech, DGA, Univ Joseph Fourier, AEPI DE nanotechnology; nanoelectronics; transistor; computing; data storage ID NANOWIRE BUILDING-BLOCKS; FIELD-EFFECT TRANSISTORS; GROWTH; ARRAYS AB Future miniaturized devices, beyond the Moore's law era of silicon, are expected to rely on new, ingenious methods to implement spatially controlled and highly functional nanoscale components synthesized by inexpensive chemistry. Chip technology based on self-assembly would enhance performance and packing density by orders of magnitude, deliver rich on-chip functionality, and operate at molecular level. Low-dimensional semiconductor nanostructues and organic molecules, which offer unique possibilities such as extremely low power dissipation, quantum effects, surface sensitivity and low synthesis cost, could be the building blocks for next-generation electronics. In this paper we discuss the potential successors of the silicon CMOS technology at the end of the ITRS Roadmap (in similar to 15 years). The disruptive technologies, rooted in nanoscale science, would aid in the continued advancement of integrated circuit technology - not necessarily through straightforward transistor geometry scaling - in several mainstream applications such as computing and data storage. (c) 2006 Elsevier Ltd. All rights reserved. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Yu, B (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM byu@arc.nasa.gov NR 31 TC 57 Z9 59 U1 3 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD APR PY 2006 VL 50 IS 4 BP 536 EP 544 DI 10.1016/j.sse.2006.03.028 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 059MS UT WOS:000238737500005 ER PT J AU Beer, J Vonmoos, M Muscheler, R AF Beer, J. Vonmoos, M. Muscheler, R. TI Solar variability over the past several millennia SO SPACE SCIENCE REVIEWS LA English DT Review DE solar activity; solar influence on climate; cosmogenic radionuclides ID EARTHS ATMOSPHERE; CLIMATE; ICE; INSOLATION; BE-10; CYCLE AB The Sun is the most important energy source for the Earth. Since the incoming solar radiation is not equally distributed and peaks at low latitudes the climate system is continuously transporting energy towards the polar regions. Any variability in the Sun-Earth system may ultimately cause a climate change. There are two main variability components that are related to the Sun. The first is due to changes in the orbital parameters of the Earth induced by the other planets. Their gravitational perturbations induce changes with characteristic time scales in the eccentricity (similar to 100,000 years), the obliquity (angle between the equator and the orbital plane) (similar to 40,000 years) and the precession of the Earth's axis (similar to 20,000 years). The second component is due to variability within the Sun. A variety of observational proxies reflecting different aspects of solar activity show similar features regarding periodic variability, trends and periods of very low solar activity (so-called grand minima) which seem to be positively correlated with the total and the spectral solar irradiance. The length of these records ranges from 25 years (solar irradiance) to 400 years (sunspots). In order to establish a quantitative relationship between solar variability and solar forcing it is necessary to extend the records of solar variability much further back in time and to identify the physical processes linking solar activity and total and spectral solar irradiance. The first step, the extension of solar variability, can be achieved by using cosmogenic radionuclides such as Be-10 in ice cores. After removing the effect of the changing geomagnetic field, a 9000-year long record of solar modulation was obtained. Comparison with paleoclimatic data provides strong evidence for a causal relationship between solar variability and climate change. It will be the subject of the next step to investigate the underlying physical processes that link solar variability with the total and spectral solar irradiance. C1 Swiss Fed Inst Environm Sci & Technol EAWAG, CH-8600 Dubendorf, Switzerland. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Beer, J (reprint author), Swiss Fed Inst Environm Sci & Technol EAWAG, Ueberlandstr 133, CH-8600 Dubendorf, Switzerland. EM beer@eawag.ch NR 24 TC 31 Z9 33 U1 0 U2 14 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD APR PY 2006 VL 125 IS 1-4 BP 67 EP 79 DI 10.1007/s11214-006-9047-4 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139RF UT WOS:000244449400007 ER PT J AU Kaufman, YJ AF Kaufman, Y. J. TI Satellite observations of natural and anthropogenic aerosol effects on clouds and climate SO SPACE SCIENCE REVIEWS LA English DT Review DE anthropogenic; aerosols; cloud aerosol interaction; MODIS ID POLLUTION; OCEAN; SMOKE; MODEL; DUST AB Anthropogenic aerosols affect the climate system and the hydrological cycle. The net effect of aerosols is to cool the climate system, directly by reflecting sunlight to space, and indirectly by increasing the brightness and cover of clouds that in turn also reflect more sunlight to space. The uncertainty in the aerosol effect on climate is 5 times greater than that of the greenhouse gases. The reason for this is the short aerosol lifetime and chemical complexity, that makes it difficult to represent the global aerosol budget from surface or aircraft measurements. Satellites provide daily global information about the aerosol content, generating large statistics with excellent regional and global representation of the aerosol column concentration, and differentiating fine from coarse aerosol. Here we use observations performed with the MODIS instrument onboard the Terra and Aqua satellites to differentiate natural from anthropogenic aerosols, and to measure the aerosol effect on cloud properties and on the reflectivity of sunlight. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kaufman, YJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM lorraine.a.remer@nasa.gov NR 19 TC 2 Z9 2 U1 0 U2 9 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD APR PY 2006 VL 125 IS 1-4 BP 139 EP 147 DI 10.1007/s11214-006-9052-7 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139RF UT WOS:000244449400012 ER PT J AU Jackman, CH Deland, MT Labow, GJ Fleming, EL Lopez-Puertas, M AF Jackman, C. H. Deland, M. T. Labow, G. J. Fleming, E. L. Lopez-Puertas, M. TI Satellite measurements of middle atmospheric impacts by solar proton events in solar cycle 23 SO SPACE SCIENCE REVIEWS LA English DT Review DE ozone; NOy; solar proton event; middle atmosphere; stratosphere; mesosphere ID PARTICLE-PRECIPITATION EVENTS; ODD NITROGEN; NITRIC-OXIDE; OZONE DEPLETION; ION CHEMISTRY; OCTOBER 1989; STRATOSPHERE; MESOSPHERE; OZONOSPHERE; CYCLE-21 AB Solar cycle 23 was extremely active with seven of the largest twelve solar proton events (SPEs) in the past forty years recorded. These events caused significant polar middle atmospheric changes that were observed by a number of satellites. The highly energetic protons produced ionizations, excitations, dissociations, and dissociative ionizations of the background constituents in the polar cap regions (> 60 degrees geomagnetic latitude), which led to the production of HOx (H, OH, HO2) and NOy (N, NO, NO2, NO3, N2O5, HNO3, HO2NO2, BrONO2, ClONO2). The HOx increases led to short-lived ozone decreases in the polar mesosphere and upper stratosphere due to the short lifetimes of the HOx constituents. Polar middle mesospheric ozone decreases greater than 50 % were observed and computed to last for hours to days due to the enhanced HOx. The NOy increases led to long-lived polar stratospheric ozone changes because of the long lifetime of the NOy family in this region. Upper stratospheric ozone decreases of > 10 % were computed to last for several months past the solar events in the winter polar regions because of the enhanced NOy. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD USA. CSIC, Inst Astrofis Andalucia, Granada, Spain. RP Jackman, CH (reprint author), NASA, Goddard Space Flight Ctr, Code 613-3, Greenbelt, MD 20771 USA. EM charles.h.jackman@nasa.gov RI Lopez Puertas, Manuel/M-8219-2013; Jackman, Charles/D-4699-2012 OI Lopez Puertas, Manuel/0000-0003-2941-7734; NR 41 TC 10 Z9 11 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD APR PY 2006 VL 125 IS 1-4 BP 381 EP 391 DI 10.1007/s11214-006-9071-4 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139RF UT WOS:000244449400031 ER PT J AU Hilsenrath, E Schoeberl, MR Douglass, AR Bhartia, PK Barnett, J Beer, R Waters, J Gunson, M Froidevaux, L Gille, J Levelt, PF AF Hilsenrath, E. Schoeberl, M. R. Douglass, A. R. Bhartia, P. K. Barnett, J. Beer, R. Waters, J. Gunson, M. Froidevaux, L. Gille, J. Levelt, P. F. TI Early data from Aura and continuity from UARS and TOMS SO SPACE SCIENCE REVIEWS LA English DT Review DE satellite observations; atmospheric composition ID TROPOSPHERIC WATER-VAPOR; MICROWAVE LIMB SOUNDER; OZONE; MLS; SATELLITE AB Aura, the last of the large EOS observatories, was launched on July 15, 2004. Aura is designed to make comprehensive stratospheric and tropospheric composition measurements from its four instruments, HIRDLS, MLS, OMI and TES. These four instruments work in synergy to provide data on ozone trends, air quality and climate change. The instruments observe in the nadir and limb and provide the best horizontal and vertical resolution ever achieved from space. After over one year in orbit the instruments are nearly operational and providing data to the scientific community. We summarize the mission, instruments, and initial results and give examples of how Aura will provide continuity to earlier chemistry missions. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Oxford, Oxford, England. Jet Prop Lab, Pasadena, CA USA. Univ Colorado, Boulder, CO 80309 USA. Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. RP Hilsenrath, E (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM ernest.hilsenrath@nasa.gov RI Douglass, Anne/D-4655-2012; Bhartia, Pawan/A-4209-2016 OI Bhartia, Pawan/0000-0001-8307-9137 NR 21 TC 2 Z9 2 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD APR PY 2006 VL 125 IS 1-4 BP 417 EP 430 DI 10.1007/s11214-006-9074-1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 139RF UT WOS:000244449400034 ER PT J AU Li, G Azarm, S Farhang-Mehr, A Diaz, AR AF Li, G Azarm, S Farhang-Mehr, A Diaz, AR TI Approximation of multiresponse deterministic engineering simulations: a dependent metamodeling approach SO STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION LA English DT Article DE metamodeling; response surface methodology; approximation methods ID MATHEMATICAL-THEORY; OPTIMIZATION; COMMUNICATION; DESIGN AB A new approach to metamodeling is introduced whereby a sequential technique is used to construct and simultaneously update mutually dependent metamodels for multiresponse, high-fidelity deterministic simulations. Unlike conventional approaches which produce a single metamodel for each scalar response independently, the present method uses the correlation among different simulation responses in the construction of the metamodel. These dependent metamodels are solved as a system of equations to estimate all individual responses simultaneously. Since several responses contribute to the construction of each individual metamodel, more information from the computed responses is used, thus improving the accuracy of the obtained metamodels. Examples are used to explore the relative performance of the proposed approach and show that the new approach outperforms conventional metamodeling approaches in terms of approximation accuracy. The new method should be particularly useful in problems that require very computationally intensive simulations. C1 Michigan State Univ, Dept Engn Mech, E Lansing, MI 48824 USA. Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. NASA Ames Res Ctr, Moffett Field, CA 94041 USA. RP Diaz, AR (reprint author), Michigan State Univ, Dept Engn Mech, E Lansing, MI 48824 USA. EM diaz@egr.msu.edu NR 27 TC 12 Z9 12 U1 0 U2 3 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1615-147X J9 STRUCT MULTIDISCIP O JI Struct. Multidiscip. Optim. PD APR PY 2006 VL 31 IS 4 BP 260 EP 269 DI 10.1007/s00158-005-0574-5 PG 10 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary; Mechanics SC Computer Science; Engineering; Mechanics GA 021RK UT WOS:000236002400002 ER PT J AU Hull, PV Tinker, ML Dozier, G AF Hull, PV Tinker, ML Dozier, G TI Evolutionary optimization of a geometrically refined truss SO STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION LA English DT Article DE subdivision; elastostatic; topology; optimization; genetic algorithms ID COMPLIANT MECHANISMS; TOPOLOGY OPTIMIZATION; DESIGN; CONSTRAINT; SURFACES AB Structural optimization is a field of research that has experienced noteworthy growth for many years. Researchers in this area have developed optimization tools to successfully design and model structures, typically minimizing mass while maintaining certain deflection and stress constraints. Numerous optimization studies have been performed to minimize mass, deflection, and stress on a benchmark cantilever truss problem. Predominantly, traditional optimization theory is applied to this problem. The cross-sectional area of each member is optimized to minimize the aforementioned objectives. This paper will present a structural optimization technique that has been previously applied to compliant mechanism design. This technique demonstrates a method that combines topology optimization, geometric refinement, finite element analysis, and two forms of evolutionary computation-genetic algorithms and differential evolution-to successfully optimize a benchmark structural optimization problem. A nontraditional solution to the benchmark problem is presented in this paper, specifically, a geometrically refined topological solution. The design process begins with an alternate control mesh formulation, multilevel geometric smoothing operation, and an elastostatic structural analysis. The design process is wrapped in an evolutionary computing optimization tool set. C1 NASA Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Auburn Univ, Auburn, AL USA. RP Hull, PV (reprint author), NASA Marshall Space Flight Ctr, EV 11, Huntsville, AL 35812 USA. EM patrick.v.hull@msfc.nasa.gov; mike.tinker@.nasa.gov; doziegv@eng.auburn.edu NR 33 TC 3 Z9 4 U1 1 U2 3 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1615-147X J9 STRUCT MULTIDISCIP O JI Struct. Multidiscip. Optim. PD APR PY 2006 VL 31 IS 4 BP 311 EP 319 DI 10.1007/s00158-005-0564-7 PG 9 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary; Mechanics SC Computer Science; Engineering; Mechanics GA 021RK UT WOS:000236002400006 ER PT J AU DellaCorte, C AF DellaCorte, C TI Global warming: Maybe an idea worth revisiting SO TRIBOLOGY & LUBRICATION TECHNOLOGY LA English DT Editorial Material C1 NASA, Glenn Res Ctr, Cleveland, OH USA. RP DellaCorte, C (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 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 APR PY 2006 VL 62 IS 4 BP 6 EP 6 PG 1 WC Engineering, Mechanical SC Engineering GA 032LS UT WOS:000236776500002 ER PT J AU Brown, ME AF Brown, ME TI Assessing natural resource management challenges in Senegal using data from participatory rural appraisals and remote sensing SO WORLD DEVELOPMENT LA English DT Article DE participatory rural appraisal; PRA; RRA; Senegal; The Gambia; West Africa; natural resource management; Sahel; remote sensing; environmental variability ID NDVI-VEGETATION MODELS; NET PRIMARY PRODUCTION; CLIMATIC INFORMATION; AFRICA; AVHRR AB This study demonstrates that there is a relationship between socioeconomic problems in parts of West Africa and remote-sensing-derived environmental information about the region (normalized difference vegetation index (NDVI), net primary production (NPP), and gridded rainfall data). Further, it finds that using both remotely sensed data and site-specific information from participatory rural appraisal (PRA) reports enables an improved understanding of natural resource management problems in the region. The study uses 100 PRA reports as sources of data on socioeconomic and natural resource management problems in Senegal and The Gambia. Utilizing a binary variable to extract semi-quantitative information from the reports, the study examines 10 PRA tools for their usefulness. (c) 2006 Elsevier Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, SSAI, Greenbelt, MD 20771 USA. RP Brown, ME (reprint author), NASA, Goddard Space Flight Ctr, SSAI, Greenbelt, MD 20771 USA. RI Brown, Molly/E-2724-2010 OI Brown, Molly/0000-0001-7384-3314 NR 53 TC 12 Z9 16 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0305-750X J9 WORLD DEV JI World Dev. PD APR PY 2006 VL 34 IS 4 BP 751 EP 767 DI 10.1016/j.worlddev.2005.10.002 PG 17 WC Economics; Planning & Development SC Business & Economics; Public Administration GA 033IW UT WOS:000236841500008 ER PT J AU Ukhorskiy, AY Anderson, BJ Takahashi, K Tsyganenko, NA AF Ukhorskiy, AY Anderson, BJ Takahashi, K Tsyganenko, NA TI Impact of ULF oscillations in solar wind dynamic pressure on the outer radiation belt electrons SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INNER MAGNETOSPHERE; GEOMAGNETIC STORMS; FIELD; DIFFUSION; ACCELERATION; TRANSPORT AB This work addresses radial transport of outer radiation belt electrons due to ULF disturbances of geomagnetic field. A new approach to calculating inductive electric field is developed and implemented using a dynamical model of the storm-time geomagnetic field. The approach is used to analyze the effects associated with solar wind dynamic pressure (P-dyn). It is found that P-dyn produces large-scale electric fields with maximum intensity at noon and midnight local time. Derived fields are used in test particle calculations of relativistic electron dynamics. The results show that even moderate oscillations of P-dyn typical for quiet-time magnetosphere can result in rapid electron scattering across the drift shells, which identifies P-dyn as one of the primary mechanisms of radial transport in the belt. Calculations show that electron motion is inconsistent with radial diffusion, and hence a more detailed description is required for accurate predictions of electron fluxes in the belt. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA, Univ Space Res Assoc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ukhorskiy, AY (reprint author), Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA. EM aleksandr.ukhorskiy@jhuapl.edu RI Anderson, Brian/I-8615-2012; Tsyganenko, Nikolai/J-7377-2012; Ukhorskiy, Aleksandr/E-6429-2016 OI Tsyganenko, Nikolai/0000-0002-5938-1579; Ukhorskiy, Aleksandr/0000-0002-3326-4024 NR 13 TC 39 Z9 39 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 MAR 31 PY 2006 VL 33 IS 6 AR L06111 DI 10.1029/2005GL024380 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 031UM UT WOS:000236729700001 ER PT J AU Tobin, DC Revercomb, HE Knuteson, RO Best, FA Smith, WL Ciganovich, NN Dedecker, RG Dutcher, S Ellington, SD Garcia, RK Howell, HB LaPorte, DD Mango, SA Pagano, TS Taylor, JK van Delst, P Vinson, KH Werner, MW AF Tobin, DC Revercomb, HE Knuteson, RO Best, FA Smith, WL Ciganovich, NN Dedecker, RG Dutcher, S Ellington, SD Garcia, RK Howell, HB LaPorte, DD Mango, SA Pagano, TS Taylor, JK van Delst, P Vinson, KH Werner, MW TI Radiometric and spectral validation of atmospheric infrared sounder observations with the aircraft-based scanning high-resolution interferometer sounder SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EMITTED RADIANCE INTERFEROMETER; FOURIER-TRANSFORM SPECTROMETERS; CALIBRATION; AIRS; PRELAUNCH; DESIGN AB The ability to accurately validate high-spectral resolution infrared radiance measurements from space using comparisons with a high-altitude aircraft spectrometer has been successfully demonstrated. The demonstration is based on a 21 November 2002 underflight of the AIRS on the NASA Aqua spacecraft by the Scanning-HIS on the NASA ER-2 high-altitude aircraft. A comparison technique which accounts for the different viewing geometries and spectral characteristics of the two sensors is introduced, and accurate comparisons are made for AIRS channels throughout the infrared spectrum. Resulting brightness temperature differences are found to be 0.2 K or less for most channels. Both the AIRS and the Scanning-HIS calibrations are expected to be very accurate (formal 3-sigma estimates are better than 1 K absolute brightness temperature for a wide range of scene temperatures), because high spectral resolution offers inherent advantages for absolute calibration and because they make use of high-emissivity cavity blackbodies as onboard radiometric references. AIRS also has the added advantage of a cold space view, and the Scanning-HIS calibration has recently benefited from the availability of a zenith view from high-altitude flights. Aircraft comparisons of this type provide a mechanism for periodically testing the absolute calibration of spacecraft instruments with instrumentation for which the calibration can be carefully maintained on the ground. This capability is especially valuable for assuring the long-term consistency and accuracy of climate observations, including those from the NASA EOS spacecraft (Terra, Aqua and Aura) and the new complement of NPOESS operational instruments. The validation role for accurately calibrated aircraft spectrometers also includes application to broadband instruments and linking the calibrations of similar instruments on different spacecraft. It is expected that aircraft flights of the Scanning-HIS and its close cousin the NPOESS Airborne Sounder Test Bed (NAST) will be used to check the long-term stability of AIRS and the NPOESS operational follow-on sounder, the Cross-track Infrared Sounder (CrIS), over the life of the missions. C1 Univ Wisconsin, Ctr Space Sci & Engn, Cooperat Inst Meteorol Satellite Studies, Madison, WI 53706 USA. Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. NPOESS Integrated Program Off, Silver Spring, MD 20910 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Tobin, DC (reprint author), Univ Wisconsin, Ctr Space Sci & Engn, Cooperat Inst Meteorol Satellite Studies, 1225 W Dayton St, Madison, WI 53706 USA. EM dave.tobin@ssec.wisc.edu NR 19 TC 55 Z9 56 U1 0 U2 6 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 MAR 31 PY 2006 VL 111 IS D9 AR D09S02 DI 10.1029/2005JD006094 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031UX UT WOS:000236730900001 ER PT J AU Tobin, DC Revercomb, HE Moeller, CC Pagano, TS AF Tobin, DC Revercomb, HE Moeller, CC Pagano, TS TI Use of atmospheric infrared sounder high-spectral resolution spectra to assess the calibration of Moderate resolution Imaging Spectroradiometer on EOS Aqua SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AIRS; MODIS; RADIANCES; PRELAUNCH; RETRIEVAL; SATELLITE; PRODUCTS; MISSION; WATER AB AIRS and MODIS on the EOS Aqua spacecraft collect global observations of the Earth's upwelling infrared radiance for numerous remote sensing and climate related applications. This paper presents comparisons of the AIRS and MODIS radiance observations and illustrates the utility of using high-spectral resolution observations to create a highly accurate assessment of broadband sensor calibration. In the analysis, the high-spectral resolution AIRS spectra are reduced to MODIS spectral resolution, and the high-spatial resolution MODIS data are reduced to AIRS spatial resolution for global data collected on 6 September 2002 and 18 February 2004. Spatially uniform scenes are selected, and the observed differences are characterized as a function of several parameters including scene temperature, sensor scan (view) angle, and solar zenith angle. The comparisons are in general very good with respect to the expected radiometric accuracies of the sensors, with mean brightness temperature differences of 0.1 K or less for many of the MODIS bands. Uncertainties of these determinations range from near 0 K for window region bands to as large as 0.2 K for other bands. For MODIS water vapor bands 27 (6.8 mu m) and 28 (7.3 mu m) and temperature sounding bands 34 (13.7 mu m), 35 (13.9 mu m), and 36 (14.2 mu m), the differences exhibit a dependence on scene temperature, with peak differences exceeding 1 K for bands 27 and 36. Differences as a function of scan angle are 0.4 K or less for all bands, and scan angles but clear trends are defined. Results for the 2 days demonstrate good reproducibility with changes in mean differences of 0.1 K or less for most bands. C1 Univ Wisconsin, Ctr Space Sci & Engn, Cooperat Inst Meteorol Satellite Studies, Madison, WI 53706 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Tobin, DC (reprint author), Univ Wisconsin, Ctr Space Sci & Engn, Cooperat Inst Meteorol Satellite Studies, 1225 W Dayton St, Madison, WI 53706 USA. EM dave.tobin@ssec.wisc.edu NR 28 TC 70 Z9 73 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 MAR 31 PY 2006 VL 111 IS D9 AR D09S05 DI 10.1029/2005JD006095 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031UX UT WOS:000236730900002 ER PT J AU Fensholt, R Sandholt, I Stisen, S Tucker, C AF Fensholt, R Sandholt, I Stisen, S Tucker, C TI Analysing NDVI for the African continent using the geostationary meteosat second generation SEVIRI sensor SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE Africa; geostationary; in situ measurements; NDVI; MSG; vegetation monitoring ID VEGETATION INDEXES; BIDIRECTIONAL REFLECTANCES; SURFACE ALBEDO; HOT-SPOT; LAND; BRDF; CANOPY; POLDER; RED; INSTRUMENT AB This study presents first results on Normalized Difference Vegetation Index (NDVI), from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) sensor onboard the geostationary satellite Meteosat Second Generation (MSG) covering the African continent. With a temporal resolution of 15 min MSG offers complementary information for NDVI monitoring compared to vegetation monitoring based on polar orbiting satellites. The improved temporal resolution has potential implications for accurate NDVI assessment of the African continent; e.g. the increased amount of available scenes are expected to help overcome problems related to cloud cover which makes the MSG data particularly well suited for early warning systems. Time series of 2004 MSG NDVI was compared to MODIS (Moderate Resolution Imaging Spectroradiometer) Terra and Aqua NDVI for the Dahra site in the Senegalese Sahel, West Africa. It was found that NDVI was available for 82 days with multiple cloud free acquisitions per day during the growing season as compared to 47 days with information from either MODIS Terra or Aqua for that particular site. Differences in MSG SEVIRI and MODIS BRDF on a seasonal scale were found to influence the time series of NDVI for the test site; MSG NDVI being higher than MODIS in July-August and lower in October-November. Preliminary composite analysis suggests that the period of compositing to produce continent scale cloud free products can be reduced to similar to 5 days using MSG NDVI as compared to polar orbiting data. With the availability of diurnal reflectance information the significance of differences between the red and near-infrared wavelengths due to anisotropy become evident, causing diurnal variations in observed NDVI. Diurnal MSG NDVI was compared to in situ measured MSG NDVI at the test site in Senegal and the same "bowl-shaped" diurnal curve was found for a medium dense cover of annual grasses. The range in observed NDVI and time of diurnal minimum was different due to different viewing geometry. Daily minimum of in situ measured NDVI was around solar noon whereas minimum MSG NDVI occurs one hour prior to noon due to the test site location 12 degrees west of the satellite sensor. Diurnal variation in observed NDVI was studied for a number of pixels characterized by different sensor view zenith angles and vegetation types. This analysis illustrated the diurnal NDVI dependency of illumination conditions, view angle and vegetation intensity and pinpoints the importance of proper BRDF modeling to produce daily values of MSG NDVI normalized for acquisition time, which will be the subject of a forthcoming paper. (c) 2006 Elsevier Inc. All rights reserved. C1 Univ Copenhagen, Inst Geog, DK-1350 Copenhagen, Denmark. Univ Copenhagen, Inst Geog, Copenhagen, Denmark. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fensholt, R (reprint author), Univ Copenhagen, Inst Geog, Oster Voldgade 10, DK-1350 Copenhagen, Denmark. EM rf@geogr.ku.dk RI Fensholt, Rasmus/L-7951-2014 OI Fensholt, Rasmus/0000-0003-3067-4527 NR 49 TC 43 Z9 44 U1 1 U2 12 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 MAR 30 PY 2006 VL 101 IS 2 BP 212 EP 229 DI 10.1016/j.rse.2005.11.013 PG 18 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 028LQ UT WOS:000236489400006 ER PT J AU Funk, CC Brown, ME AF Funk, CC Brown, ME TI Intra-seasonal NDVI change projections in semi-arid Africa SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE early warning; Africa; food security; NDVI; precipitation; rainfall; malaria; rift valley fever; pastoral livelihoods ID RIFT-VALLEY FEVER; DIFFERENCE VEGETATION INDEX; NET PRIMARY PRODUCTION; SOUTHERN AFRICA; NOAA AVHRR; INTERANNUAL VARIABILITY; EAST-AFRICA; TIME-SERIES; CLIMATE; RAINFALL AB Early warning systems (EWS) tend to focus on the identification of slow onset disasters such famine and epidemic disease. Since hazardous environmental conditions often precede disastrous outcomes by many months, effective monitoring via satellite and in situ observations can successfully guide mitigation activities. Accurate short term forecasts of NDVI Could increase lead times, making early warning earlier. This paper presents a simple empirical model for making 1 to 4 month NDVI projections. These statistical projections are based on parameterized satellite rainfall estimates (RFE) and relative humidity demand (RHD). A quasi-global, I month ahead, F study demonstrates reasonable accuracies in many semi-arid regions. In Africa, a 0.1 degrees cross-validated skill assessment quantifies the technique's applicability at 1 to 4 month forecast intervals. These results suggest that useful projections can be made over many semi-arid, food insecure regions of Africa, with plausible extensions to drought prone areas of Asia, Australia and South America. (c) 2006 Elsevier Inc. All rights reserved. C1 Univ Calif Santa Barbara, Dept Geog, Climate Hazard Grp, Santa Barbara, CA 93106 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Funk, CC (reprint author), Univ Calif Santa Barbara, Dept Geog, Climate Hazard Grp, Santa Barbara, CA 93106 USA. EM chris@geog.ucsb.edu RI Brown, Molly/E-2724-2010; Brown, Molly/M-5146-2013 OI Brown, Molly/0000-0001-7384-3314; Brown, Molly/0000-0001-7384-3314 NR 69 TC 46 Z9 48 U1 0 U2 15 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAR 30 PY 2006 VL 101 IS 2 BP 249 EP 256 DI 10.1016/j.rse.2005.12.014 PG 8 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 028LQ UT WOS:000236489400008 ER PT J AU Huang, JP Minnis, P Lin, B Wang, TH Yi, YH Hu, YX Sun-Mack, S Ayers, K AF Huang, JP Minnis, P Lin, B Wang, TH Yi, YH Hu, YX Sun-Mack, S Ayers, K TI Possible influences of Asian dust aerosols on cloud properties and radiative forcing observed from MODIS and CERES SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID DESERT DUST; ICE NUCLEI; SATELLITE; ISRAEL AB The effects of dust storms on cloud properties and Radiative Forcing (RF) are analyzed over Northwestern China from April 2001 to June 2004 using data collected by the MODerate Resolution Imaging Spectroradiometer ( MODIS) and Clouds and the Earth's Radiant Energy System (CERES) instruments on the Aqua and Terra satellites. On average, ice cloud effective particle diameter, optical depth and ice water path of cirrus clouds under dust polluted conditions are 11%, 32.8%, and 42% less, respectively, than those derived from ice clouds in dust-free atmospheric environments. Due to changes in cloud microphysics, the instantaneous net RF is increased from -161.6 W/m(2) for dust-free clouds to -118.6 W/m(2) for dust-contaminated clouds. C1 Lanzhou Univ, Coll Atmospher Sci, Lanzhou 730000, Peoples R China. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Analyt Serv & Mat Inc, Hampton, VA 23666 USA. Sci Applicat Int Corp, Hampton, VA 23666 USA. RP Huang, JP (reprint author), Lanzhou Univ, Coll Atmospher Sci, Lanzhou 730000, Peoples R China. EM j.huang@larc.nasa.gov RI Wang, Tianhe/F-8236-2012; Minnis, Patrick/G-1902-2010; Hu, Yongxiang/K-4426-2012 OI Minnis, Patrick/0000-0002-4733-6148; NR 15 TC 113 Z9 128 U1 2 U2 18 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 MAR 29 PY 2006 VL 33 IS 6 AR L06824 DI 10.1029/2005GL024724 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 031UI UT WOS:000236729300003 ER PT J AU Qi, N Appel, WS LeVan, MD Finn, JE AF Qi, N Appel, WS LeVan, MD Finn, JE TI Adsorption dynamics of organic compounds and water vapor in activated carbon beds SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID DIFFUSION; MIXTURES; KINETICS; MULTILAYER; TRANSPORT; SORPTION; SURFACE AB Breakthrough behavior is investigated for an activated carbon bed fed with constant concentrations of organic vapors and a stepped concentration of water vapor. The organics are present as single components and binary mixtures, with both hydrophobic and hydrophilic organics considered. Experiments are performed using a fully automated fixed-bed apparatus, which enables breakthrough curve studies for gas mixtures over a wide range of concentrations, from much less than 1 ppm up to saturation. The adsorbed-phase mass transfer coefficient of water is found to be a strong function of water loading. The system response is complex. with behaviors for hydrophilic and hydrophobic compounds being quite different. A model incorporating all accurate description of the highly nonideal adsorption equilibria is developed to simulate all of the fixed-bed experiments and gives good agreement in time, trend, extent, and shape of the breakthrough curves. C1 Vanderbilt Univ, Dept Chem Engn, Nashville, TN 37235 USA. NASA, Ames Res Ctr, Astrobiol Technol Branch, Moffett Field, CA 94035 USA. RP LeVan, MD (reprint author), Vanderbilt Univ, Dept Chem Engn, Nashville, TN 37235 USA. EM m.douglas.levan@vanderbilt.edu NR 25 TC 30 Z9 31 U1 1 U2 24 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAR 29 PY 2006 VL 45 IS 7 BP 2303 EP 2314 DI 10.1021/ie050758x PG 12 WC Engineering, Chemical SC Engineering GA 031PD UT WOS:000236715600019 ER PT J AU Cakmur, RV Miller, RL Perlwitz, J Geogdzhayev, IV Ginoux, P Koch, D Kohfeld, KE Tegen, I Zender, CS AF Cakmur, RV Miller, RL Perlwitz, J Geogdzhayev, IV Ginoux, P Koch, D Kohfeld, KE Tegen, I Zender, CS TI Constraining the magnitude of the global dust cycle by minimizing the difference between a model and observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; AEROSOL OPTICAL DEPTH; SKY RADIANCE MEASUREMENTS; SAHARAN DUST; MINERAL DUST; RELATIVE IMPORTANCE; DESERT DUST; LAND-USE; GODDARD INSTITUTE; TROPICAL ATLANTIC AB Current estimates of global dust emission vary by over a factor of two. Here, we use multiple data types and a worldwide array of stations combined with a dust model to constrain the magnitude of the global dust cycle for particles with radii between 0.1 and 8 mm. An optimal value of global emission is calculated by minimizing the difference between the model dust distribution and observations. The optimal global emission is most sensitive to the prescription of the dust source region. Depending upon the assumed source, the agreement with observations is greatest for global, annual emission ranging from 1500 to 2600 Tg. However, global annual emission between 1000 and 3000 Tg remains in agreement with the observations, given small changes in the method of optimization. Both ranges include values that are substantially larger than calculated by current dust models. In contrast, the optimal fraction of clay particles (whose radii are less than 1 mm) is lower than current model estimates. The optimal solution identified by a combination of data sets is different from that identified by any single data set and is more robust. Uncertainty is introduced into the optimal emission by model biases and the uncertain contribution of other aerosol species to the observations. C1 Natl Acad Sci, Washington, DC 20418 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10025 USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY USA. CUNY Queens Coll, Sch Earth & Environm Sci, Flushing, NY 11367 USA. Leibniz Inst Tropospher Res, D-04318 Leipzig, Germany. Univ Calif Irvine, Dept Earth Syst Sci, Phys Sci Res Facil 205, Irvine, CA 92697 USA. RP Natl Acad Sci, 2101 Constitut Ave Nw, Washington, DC 20418 USA. EM rcakmur@giss.nasa.gov; rlm15@columbia.edu; jp544@columbia.edu; igeogdzhayev@giss.nasa.gov; paul.ginoux@noaa.gov; dkoch@giss.nasa.gov; kek@qc.edu; itegen@tropos.de; zender@uci.edu RI Zender, Charles/D-4485-2012; Miller, Ron/E-1902-2012; Ginoux, Paul/C-2326-2008 OI Zender, Charles/0000-0003-0129-8024; Ginoux, Paul/0000-0003-3642-2988 NR 77 TC 95 Z9 96 U1 2 U2 13 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 MAR 29 PY 2006 VL 111 IS D6 AR D06207 DI 10.1029/2005JD005791 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031US UT WOS:000236730400003 ER PT J AU Irie, H Sugita, T Nakajima, H Yokota, T Oelhaf, H Wetzel, G Toon, GC Sen, B Santee, ML Terao, Y Saitoh, N Ejiri, MK Tanaka, T Kondo, Y Kanzawa, H Kobayashi, H Sasano, Y AF Irie, H Sugita, T Nakajima, H Yokota, T Oelhaf, H Wetzel, G Toon, GC Sen, B Santee, ML Terao, Y Saitoh, N Ejiri, MK Tanaka, T Kondo, Y Kanzawa, H Kobayashi, H Sasano, Y TI Validation of stratospheric nitric acid profiles observed by Improved Limb Atmospheric Spectrometer (ILAS)-II SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOUNDER HNO3 OBSERVATIONS; REACTIVE NITROGEN; POLAR VORTEX; RETRIEVAL ALGORITHM; ILAS; CLOUDS; WINTER; OZONE; O-3; DENITRIFICATION AB The Improved Limb Atmospheric Spectrometer-II (ILAS-II) was launched aboard the Advanced Earth Observing Satellite-II (ADEOS-II) in December 2002. Stratospheric vertical profiles of nitric acid (HNO3) concentration observed by ILAS-II (version 1.4) are validated using coincident HNO3 measurements by balloon-borne instruments (MIPAS-B2 and MkIV) in March and April 2003. Further validation is performed by making climatological comparisons of lower stratospheric HNO3-ozone (O-3) correlations obtained by ILAS-II and ILAS ( the predecessor of ILAS-II) for specific potential vorticity-based equivalent latitudes and seasons where and when ILAS data showed very compact correlations in 1997. The reduced scatter of ILAS-II HNO3 values around the reference HNO3, which is derived from ILAS-II O-3 using the ILAS HNO3-O-3 correlation, shows that the precision of the ILAS-II HNO3 data is better than 13-14%, 5%, and 1% at 15, 20, and 25 km, respectively. Combining all of the comparisons made in the present study, the accuracy of the ILAS-II HNO3 profiles at 15-25 km is estimated to be better than -13%/+26%. C1 Japan Agcy Marine Earth Sci & Technol, Frontier Res Ctr Global Change, Kanazawa Ku, Kanagawa 2360001, Japan. Natl Inst Environm Studies, Tsukuba, Ibaraki 3058506, Japan. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Univ Tokyo, Adv Sci & Technol Res Ctr, Meguro Ku, Tokyo 1538904, Japan. Nagoya Univ, Grad Sch Environm Studies, Dept Earth & Environm Sci, Chikusa Ku, Aichi 4648601, Japan. Cent Res Inst Elect Power Ind, Chiyoda Ku, Tokyo 1008126, Japan. RP Irie, H (reprint author), Japan Agcy Marine Earth Sci & Technol, Frontier Res Ctr Global Change, Kanazawa Ku, 3173-25 Showa Machi, Kanagawa 2360001, Japan. EM irie@jamstec.go.jp RI Sasano, Yasuhiro/C-2927-2009; Terao, Yukio/A-2099-2008; Kondo, Yutaka/D-1459-2012; Wetzel, Gerald/A-7065-2013; Oelhaf, Hermann/A-7895-2013; OI Sasano, Yasuhiro/0000-0001-7470-5642; Terao, Yukio/0000-0003-2345-7073; Sugita, Takafumi/0000-0002-0508-7040 NR 38 TC 21 Z9 21 U1 0 U2 0 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 MAR 29 PY 2006 VL 111 IS D11 AR D11S03 DI 10.1029/2005JD006115 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031UZ UT WOS:000236731100001 ER PT J AU Koch, D Schmidt, GA Field, CV AF Koch, D Schmidt, GA Field, CV TI Sulfur, sea salt, and radionuclide aerosols in GISS ModelE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; STRATOSPHERE-TROPOSPHERE EXCHANGE; GLOBAL 3-DIMENSIONAL SIMULATION; ATMOSPHERIC TRANSPORT MODELS; COMMUNITY CLIMATE MODEL; CHEMICAL TRACER MODEL; NATIONAL CENTER; OPTICAL-THICKNESS; EARTHS ATMOSPHERE; GODDARD INSTITUTE AB We simulate a suite of aerosols in the new GISS ModelE GCM: present-day sulfur species and the natural species sea salt, radionuclides Be-7 (stratospheric source), and Pb-210 (derived from Rn-222 from soils). The natural species are used to test the model and to help diagnose the anthropogenic sulfur species. Model improvements over previous versions include increased vertical resolution, addition of a stratiform dissolved species budget (DSB), better tracer coupling to the boundary layer, and an improved relative humidity-dependent radiative scheme. The DSB reduces the loads of most soluble species since it increases stratiform precipitation scavenging. We compare the model with extensive surface and aircraft concentration measurements in the troposphere and stratosphere. We compare three different formulations of the Rn-222 emissions and find that a scheme with reduced radon flux at high latitudes of the Northern Hemisphere for all seasons gives the best Pb-210 results. Although the Rn-222 emissions appear to be approximately the right order of magnitude, model Pb-210 is too large. Conversely, our Be-7 source is too small (since concentrations in the upper troposphere and stratosphere are deficient), while the Be-7 surface concentrations are as observed. These radionuclide results suggests that model scavenging (by moist convection) is deficient. Our new model uses increased natural sulfur emissions; however, the DSB causes sulfate to be generally less than observed and indicates a need for additional sulfur oxidation mechanisms. Model radiative forcing for sulfate and sea salt are -0.54 and -1.1 W m(-2), respectively. The anthropogenic sulfate forcing is -0.25 W m(-2), less than the -0.68 W m(-2) in our previous model mainly owing to an 18% decrease in industrial emissions. C1 Columbia Univ, NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY USA. RP Koch, D (reprint author), Columbia Univ, NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM dkoch@giss.nasa.gov RI Schmidt, Gavin/D-4427-2012 OI Schmidt, Gavin/0000-0002-2258-0486 NR 63 TC 109 Z9 112 U1 1 U2 13 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 MAR 29 PY 2006 VL 111 IS D6 AR D06206 DI 10.1029/2004JD005550 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031US UT WOS:000236730400001 ER PT J AU Miller, RL Cakmur, RV Perlwitz, J Geogdzhayev, IV Ginoux, P Koch, D Kohfeld, KE Prigent, C Ruedy, R Schmidt, GA Tegen, I AF Miller, RL Cakmur, RV Perlwitz, J Geogdzhayev, IV Ginoux, P Koch, D Kohfeld, KE Prigent, C Ruedy, R Schmidt, GA Tegen, I TI Mineral dust aerosols in the NASA goddard institute for Space Sciences ModelE atmospheric general circulation model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WIND-SPEED VARIABILITY; LAND-USE; RELATIVE IMPORTANCE; TURBULENT PBL; RADIATIVE PROPERTIES; OPTICAL-THICKNESS; SIZE DISTRIBUTION; REFRACTIVE-INDEX; SAHARAN DUST; SOURCE AREAS AB We describe an updated model of the dust aerosol cycle embedded within the NASA Goddard Institute for Space Studies 'ModelE' atmospheric general circulation model (AGCM). The model dust distribution is compared to observations ranging from aerosol optical thickness and surface concentration to deposition and size distribution. The agreement with observations is improved compared to previous distributions computed by either an older version of the GISS AGCM or an offline tracer transport model. The largest improvement is in dust transport over the Atlantic due to increased emission over the Sahara. This increase comes from subgrid wind fluctuations associated with dry convective eddies driven by intense summertime heating. Representation of 'preferred sources' of soil dust particles is also fundamental to the improvement. The observations suggest that deposition is too efficient in the model, partly due to AGCM rainfall errors. C1 Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10025 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Natl Acad Sci, Washington, DC 20418 USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY USA. CUNY Queens Coll, Sch Earth & Environm Sci, Flushing, NY 11367 USA. Observ Paris, CNRS, Lab Etud Rayonnement & Mat Astrophys, F-75014 Paris, France. Leibniz Inst Tropospher Res, D-04318 Leipzig, Germany. RP Columbia Univ, Dept Appl Phys & Appl Math, 2880 Broadway, New York, NY 10025 USA. EM rlm15@columbia.edu; rcakmur@giss.nasa.gov; jp544@columbia.edu; igeogdzhayev@giss.nasa.gov; paul.ginoux@noaa.gov; dkoch@giss.nasa.gov; kek@qc.edu; catherine.prigent@obspm.fr; rruedy@giss.nasa.gov; gschmidt@giss.nasa.gov; itegen@tropos.de RI Schmidt, Gavin/D-4427-2012; Miller, Ron/E-1902-2012; Ginoux, Paul/C-2326-2008 OI Schmidt, Gavin/0000-0002-2258-0486; Ginoux, Paul/0000-0003-3642-2988 NR 86 TC 86 Z9 88 U1 2 U2 12 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 MAR 29 PY 2006 VL 111 IS D6 AR D06208 DI 10.1029/2005JD005796 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031US UT WOS:000236730400004 ER PT J AU Giglio, L van der Werf, GR Randerson, JT Collatz, GJ Kasibhatla, P AF Giglio, L van der Werf, GR Randerson, JT Collatz, GJ Kasibhatla, P TI Global estimation of burned area using MODIS active fire observations SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID INTERANNUAL VARIABILITY; ATMOSPHERIC EMISSIONS; BIOMASS; CARBON; VEGETATION; RESOLUTION; PRODUCTS; AFRICA; REGION; SEASON AB We present a method for estimating monthly burned area globally at 1 degrees spatial resolution using Terra MODIS data and ancillary vegetation cover information. Using regression trees constructed for 14 different global regions, MODIS active fire observations were calibrated to burned area estimates derived from 500-m MODIS imagery based on the assumption that burned area is proportional to counts of fire pixels. Unlike earlier methods, we allow the constant of proportionality to vary as a function of tree and herbaceous vegetation cover, and the mean size of monthly cumulative fire-pixel clusters. In areas undergoing active deforestation, we implemented a subsequent correction based on tree cover information and a simple measure of fire persistence. Regions showing good agreement between predicted and observed burned area included Boreal Asia, Central Asia, Europe, and Temperate North America, where the estimates produced by the regression trees were relatively accurate and precise. Poorest agreement was found for southern-hemisphere South America, where predicted values of burned area are both inaccurate and imprecise; this is most likely a consequence of multiple factors that include extremely persistent cloud cover, and lower quality of the 500-m burned area maps used for calibration. Application of our approach to the nine remaining regions yielded comparatively accurate, but less precise, estimates of monthly burned area. We applied the regional regression trees to the entire archive of Terra MODIS fire data to produce a monthly global burned area data set spanning late 2000 through mid-2005. Annual totals derived from this approach showed good agreement with independent annual estimates available for nine Canadian provinces, the United States, and Russia. With our data set we estimate the global annual burned area for the years 2001-2004 to vary between 2.97 million and 3.74 million km(2), with the maximum occurring in 2001. These coarse-resolution burned area estimates may serve as a useful interim product until long-term burned area data sets from multiple sensors and retrieval approaches become available. C1 NASA, Goddard Space Flight Ctr, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. Vrije Univ Amsterdam, Dept Hydrol & Geoenvironm Sci, Amsterdam, Netherlands. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA USA. Duke Univ, Nicholas Sch Environm & Earth Sci, Durham, NC USA. RP NASA, Goddard Space Flight Ctr, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. EM giglio@hades.gsfc.nasa.gov RI Kasibhatla, Prasad/A-2574-2010; collatz, george/D-5381-2012; van der Werf, Guido/M-8260-2016; OI van der Werf, Guido/0000-0001-9042-8630; Kasibhatla, Prasad/0000-0003-3562-3737 NR 39 TC 263 Z9 276 U1 5 U2 41 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 MAR 28 PY 2006 VL 6 BP 957 EP 974 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 026LQ UT WOS:000236340800001 ER PT J AU White, SM Crisp, JA Spera, FJ AF White, SM Crisp, JA Spera, FJ TI Long-term volumetric eruption rates and magma budgets SO GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS LA English DT Review DE volcanism; magma budget; rates; volcanic repose; tectonophysics : physics of magma and magma bodies; volcanology : thermodynamics; volcanology : general or miscellaneous ID LARGE IGNEOUS PROVINCE; MID-ATLANTIC RIDGE; EAST PACIFIC RISE; LATE CENOZOIC VOLCANISM; FLOOD-BASALT PROVINCE; SOUTHERN INDIAN-OCEAN; OASIS-VALLEY CALDERA; K-AR AGE; CRUSTAL STRUCTURE; NEW-ZEALAND AB A global compilation of 170 time-averaged volumetric volcanic output rates (Q(e)) is evaluated in terms of composition and petrotectonic setting to advance the understanding of long-term rates of magma generation and eruption on Earth. Repose periods between successive eruptions at a given site and intrusive: extrusive ratios were compiled for selected volcanic centers where long-term (>10(4) years) data were available. More silicic compositions, rhyolites and andesites, have a more limited range of eruption rates than basalts. Even when high Q(e) values contributed by flood basalts (9 +/- 2 x 10(-1) km(3)/yr) are removed, there is a trend in decreasing average Q(e) with lava composition from basaltic eruptions (2.6 +/- 1.0 x 10(-2) km(3)/yr) to andesites (2.3 +/- 0.8 x 10(-3) km(3)/yr) and rhyolites (4.0 +/- 1.4 x 10(-3) km(3)/yr). This trend is also seen in the difference between oceanic and continental settings, as eruptions on oceanic crust tend to be predominately basaltic. All of the volcanoes occurring in oceanic settings fail to have statistically different mean Q(e) and have an overall average of 2.8 +/- 0.4 x 10(-2) km(3)/yr, excluding flood basalts. Likewise, all of the volcanoes on continental crust also fail to have statistically different mean Q(e) and have an overall average of 4.4 +/- 0.8 x 10(-3) km(3)/yr. Flood basalts also form a distinctive class with an average Q(e) nearly two orders of magnitude higher than any other class. However, we have found no systematic evidence linking increased intrusive: extrusive ratios with lower volcanic rates. A simple heat balance analysis suggests that the preponderance of volcanic systems must be open magmatic systems with respect to heat and matter transport in order to maintain eruptible magma at shallow depth throughout the observed lifetime of the volcano. The empirical upper limit of similar to 10(-2) km(3)/yr for magma eruption rate in systems with relatively high intrusive: extrusive ratios may be a consequence of the fundamental parameters governing rates of melt generation (e.g., subsolidus isentropic decompression, hydration due to slab dehydration and heat transfer between underplated magma and the overlying crust) in the Earth. C1 Univ S Carolina, Dept Geol Sci, Columbia, SC 29208 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Santa Barbara, Dept Earth Sci, Santa Barbara, CA 93106 USA. RP White, SM (reprint author), Univ S Carolina, Dept Geol Sci, 700 Sumter St, Columbia, SC 29208 USA. EM swhite@geol.sc.edu; joy.a.crisp@jpl.nasa.gov; spera@geol.ucsb.edu RI White, Scott/C-5339-2009; Crisp, Joy/H-8287-2016 OI White, Scott/0000-0002-5123-5307; Crisp, Joy/0000-0002-3202-4416 NR 169 TC 138 Z9 138 U1 1 U2 36 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 1525-2027 J9 GEOCHEM GEOPHY GEOSY JI Geochem. Geophys. Geosyst. PD MAR 28 PY 2006 VL 7 AR Q03010 DI 10.1029/2005GC001002 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 031UA UT WOS:000236728500002 ER PT J AU Mingo, N AF Mingo, N TI Thermoelectric figure of merit of II-VI semiconductor nanowires (vol 85, pg 5986, 2004) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 NASA, Ames Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Mingo, N (reprint author), NASA, Ames Ctr Nanotechnol, 229-1, Moffett Field, CA 94035 USA. NR 1 TC 1 Z9 1 U1 1 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 27 PY 2006 VL 88 IS 13 AR 139901 DI 10.1063/1.2192640 PG 1 WC Physics, Applied SC Physics GA 028CW UT WOS:000236465100125 ER PT J AU Allamandola, LJ AF Allamandola, Louis J. TI IR Spectroscopy of cosmic ices and organics SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM lallamandola@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 8-YCC PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125909948 ER PT J AU Allamandola, LJ AF Allamandola, Louis J. TI Interstellar PAHs: Yesterday, today, and tomorrow SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM lallamandola@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 39-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908154 ER PT J AU Barber, JR Poggi, MA Bottomley, LA McFarland, AW Colton, JS Nguyen, CV AF Barber, Jabulani R. Poggi, Mark A. Bottomley, Lawrence A. McFarland, Andrew W. Colton, Jonathan S. Nguyen, Cattien V. TI Mechanical response of carbon nanocoils under compressive load SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. Georgia Inst Technol, George W Woodruff Sch Mech Engn, Atlanta, GA 30332 USA. NASA, Ames Res Ctr, ELORET Corp, Ctr Nanotechnol, Moffett Field, CA USA. EM jabulani.barber@chemistry.gatech.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 236-INOR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125905235 ER PT J AU Brown, N Yu, J AF Brown, Nytarsha Yu, Jian TI Identification of poly(hydroxyalkanoates) in marine environments around Oahu SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 Texas So Univ, NASA, Res Ctr, Houston, TX 77004 USA. Univ Hawaii, Dept Chem, Honolulu, HI 96822 USA. EM brownnytarsha@yahoo.com NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 836-CHED PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125902158 ER PT J AU Capadona, LA Meador, MAB Alunni, A Fabrizio, E Vassilaras, P Leventis, N AF Capadona, Lynn A. Meador, Mary Ann B. Alunni, Antonella Fabrizio, Eve Vassilaras, Plousia Leventis, Nicholas TI Minimizing the density of polymer crosslinked aerogels SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Mat & Struct Div, Glenn Res Ctr, Cleveland, OH 44135 USA. EM lynn.a.capadona@nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 291-COLL PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125903291 ER PT J AU Chiar, JE AF Chiar, Jean E. TI Observations of solid state interstellar molecules SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, SETI Inst, Ctr Study Life Universe, Mountain View, CA 94043 USA. EM jchiar@seti.org NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 4-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908119 ER PT J AU Christensen, LE Noell, AC Okumura, M Hansen, JC Sander, SP Francisco, JS AF Christensen, Lance E. Noell, Aaron C. Okumura, Mitchio Hansen, Jaron C. Sander, Stanley P. Francisco, Joseph S. TI Chemistry of hydrogen-bonded HO2 complexes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 CALTECH, Arthur Amos Noyes Lab Chem Phys, Div Chem & Chem Engn, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91125 USA. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. EM mo@its.caltech.edu NR 0 TC 0 Z9 0 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 511-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908629 ER PT J AU DeVor, R Geiger, CL Clausen, CA Quinn, J Milum, KM AF DeVor, Robert Geiger, Cherie L. Clausen, Christian A. Quinn, Jacqueline Milum, Kristen M. TI tEmulsified nanoscale iron particles for environmental remediation of heavy metals SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 Univ Cent Florida, Dept Chem, Orlando, FL 32816 USA. NASA, Kennedy Space Ctr, FL 32899 USA. EM cgeiger@mail.ucf.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 290-IEC PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125904875 ER PT J AU Ehrenfreund, P AF Ehrenfreund, Pascale TI Prebiotically important interstellar molecules SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 38-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908153 ER PT J AU Geiger, CL Clausen, CA Milum, KM Quinn, J AF Geiger, Cherie L. Clausen, Christian A. Milum, Kristen M. Quinn, Jacqueline TI Kow values and solvent/iron degradation kinetics: A predictive tool for solvent degradation efficiency with emulsified, nano-scale, zero-valent iron SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 Univ Cent Florida, Dept Chem, Orlando, FL 32816 USA. NASA, Kennedy Space Ctr, FL 32899 USA. EM cgeiger@mail.ucf.edu NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 289-IEC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125904874 ER PT J AU Green, SJ Jahnke, LL Smith, JM Hogan, M Kelley, C Bebout, BM Bebout, LE AF Green, Stefan J. Jahnke, Linda L. Smith, Jason M. Hogan, Mary Kelley, Cheryl Bebout, Brad M. Bebout, Leslie E. TI Effect of sulfate manipulations on carbon cycling and microbial community structure in hypersaline microbial mats SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. Univ Florida, Gainesville, FL 32611 USA. Univ Missouri, Dept Geol Sci, Columbia, MO 65211 USA. EM sjgreen@mail.arc.nasa.gov RI Green, Stefan/C-8980-2011 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 108-GEOC PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125904535 ER PT J AU Huo, WM Chaban, GM Dateo, CE AF Huo, Winifred M. Chaban, Galina M. Dateo, Christopher E. TI Electron-impact ionization and dissociative ionization of biomolecules SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM whuo@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 160-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908275 ER PT J AU Iraci, LT Michelsen, RR Andersen, MPS AF Iraci, Laura T. Michelsen, Rebecca R. Andersen, Mads P. Sulbaek TI Temperature and composition dependence of organic reactions in aqueous, acidic atmospheric aerosols SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Earth Sci, Moffett Field, CA 94035 USA. EM laura.t.iraci@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 28-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908143 ER PT J AU Kojiro, DR Sheverev, VA Holland, PM Takeuchi, N AF Kojiro, Daniel R. Sheverev, Valery A. Holland, Paul M. Takeuchi, Norishige TI Miniature Gas Chromatograph (GC) - Penning Ionization Electron Spectroscopy (PIES) Instrument for the trace analyses of extraterrestrial environments SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Exobiol Branch, Moffett Field, CA 94035 USA. EM Daniel.R.Kojiro@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 294-ANYL PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125900401 ER PT J AU Kojiro, DR Holland, PM Stimac, RM Kaye, WJ Takeuchi, N AF Kojiro, Daniel R. Holland, Paul M. Stimac, Robert M. Kaye, William J. Takeuchi, Norishige TI Miniature GC: Minicell ion mobility spectrometer (IMS) for astrobiology planetary missions SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Exobiol Branch, Moffett Field, CA 94035 USA. Thorleaf Res Inc, Santa Barbara, CA USA. EM Daniel.R.Kojiro@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 2-ANYL PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125900109 ER PT J AU Mattioda, AL AF Mattioda, Andrew L. TI Spectroscopy of polycyclic aromatic hydrocarbons in the interstellar environment SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM amattioda@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 40-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908155 ER PT J AU Meador, MAB Capadona, LA Vassilaras, P Leventis, N AF Meador, Mary Ann B. Capadona, Lynn A. Vassilaras, Plousia Leventis, Nicholas TI Effect of processing conditions on chemical make-up of di-isocyanate crosslinked silica aerogels SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. RP Meador, MAB (reprint author), NASA, Glenn Res Ctr, Mat & Struct Div, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM maryann.meador@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 212-POLY PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125909722 ER PT J AU Messenger, S AF Messenger, Scott TI Interstellar molecules in primitive solar system materials SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Johnson Space Ctr, Robert M Walker Lab Space Sci, Houston, TX 77058 USA. EM scott.r.messenger@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 225-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908339 ER PT J AU Noell, AC Alconcel, LS Okumura, MO Sander, SP AF Noell, Aaron C. Alconcel, Leah S. Okumura, Mitchio O. Sander, Stanley P. TI Peroxy radical kinetics using infrared kinetic spectroscopy (IRKS): HO2+C2H5O2 SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 CALTECH, Div Chem & Chem Engn, Arthur Amos Noyes Lab Chem Phys, Pasadena, CA 91125 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. EM aaron@caltech.edu NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 315-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908431 ER PT J AU Pearson, JC AF Pearson, John C. TI Opening up the far-infrared: The Herschel Space Observatory SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM John.C.Pearson@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 493-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908611 ER PT J AU Remijan, AJ AF Remijan, Anthony J. TI Array observations of biologically-interesting molecules in hot molecular cores SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. EM aremijan@pop900.gsfc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 42-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908157 ER PT J AU Roberson, LB Patel, B Kowalik, J Tolbert, LM Janata, JA AF Roberson, Luke B. Patel, Biren Kowalik, Janusz Tolbert, Laren M. Janata, Jiri A. TI From common to individual gate MOS OFETs: A platform for highthroughput, reusable organic/polymer semiconductor mobility screening SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Spaceport Technol Div, KTE Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. Georgia Inst Technol, Ctr Microelect Res, Atlanta, GA 30332 USA. Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. EM luke.b.roberson@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 438-PMSE PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125909433 ER PT J AU Salama, F AF Salama, Farid TI Laboratory spectroscopy of PAHs and dust particles: From the laboratory to astronomical observations SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM Farid.Salama@nasa.gov RI Salama, Farid/A-8787-2009 OI Salama, Farid/0000-0002-6064-4401 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 113-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908228 ER PT J AU Tan, XF Zheng, W AF Tan, Xiaofeng Zheng, Weijun TI Theoretical study of the O-2-(H2O)(n) van der Waals complexes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Univ Hawaii Manoa, Inst Astron, Honolulu, HI 96822 USA. Univ Hawaii Manoa, Dept Chem, Honolulu, HI 96822 USA. EM xtan@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 453-PHYS PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908570 ER PT J AU Tan, XF Salama, F AF Tan, Xiaofeng Salama, Farid TI Computational spectroscopy of polycyclic aromatic hydrocarbons SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM xtan@mail.arc.nasa.gov RI Salama, Farid/A-8787-2009 OI Salama, Farid/0000-0002-6064-4401 NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 153-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908268 ER PT J AU Tielens, AG AF Tielens, Alexander G. TI Introduction to chemistry on granular surfaces SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 2-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125908117 ER PT J AU Tyson, DS Ilhan, F Ward, LD Meador, MAB Meador, MA AF Tyson, Daniel S. Ilhan, Faysal Ward, La'Nita D. Meador, Mary Ann B. Meador, Michael A. TI Diels-Alder trapping of photochemically generated dienes: A path toward solventless photopolymerized polyimide films SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 NASA, Glenn Res Ctr, Mat & Strcut Div, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Div Mat, Polymers Branch, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Div Mat, Cleveland, OH 44135 USA. EM Daniel.S.Tyson@grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 368-POLY PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125909878 ER PT J AU Wal, RLV Hays, MD AF Wal, Randy L. Vander Hays, Michael D. TI Differentiation of soots by analysis of HRTEM images SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 231st National Meeting of the American-Chemical-Society CY MAR 26-30, 2006 CL Atlanta, GA SP Amer Chem Soc C1 USRA, NASA, Cleveland, OH 44135 USA. EM randy@rvander.grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 26 PY 2006 VL 231 MA 117-FUEL PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 050YE UT WOS:000238125904380 ER PT J AU Li, ZH Fielding, EJ Cross, P Muller, JP AF Li, ZH Fielding, EJ Cross, P Muller, JP TI Interferometric synthetic aperture radar atmospheric correction: Medium Resolution Imaging Spectrometer and Advanced Synthetic Aperture Radar Integration SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID WATER-VAPOR; PRODUCTS; MODELS; GPS AB [1] Atmospheric water vapor effects represent one of the major limitations of repeat- pass InSAR, and limit the accuracy of deformation rates derived from InSAR. The use of contemporaneous MERIS data to correct ENVISAT ASAR measurements shows a significant reduction in water vapor effects. After correction, the RMS differences between GPS and InSAR range changes in the satellite line of sight direction decreased to 0.55 cm with a reduction of up to 0.35 cm. It is also shown that it is possible to implement an extra ' conservative' cloud mask and obtain better water vapor corrections than that from using the official ESA cloud mask product. C1 UCL, Dept Geomat Engn, London WC1E 6BT, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Li, ZH (reprint author), UCL, Dept Geomat Engn, Gower St, London WC1E 6BT, England. EM zhli@ge.ucl.ac.uk RI NCEO, COMET+`/A-3443-2013; Li, Zhenhong/F-8705-2010; Fielding, Eric/A-1288-2007; OI Li, Zhenhong/0000-0002-8054-7449; Fielding, Eric/0000-0002-6648-8067; Muller, Jan-Peter/0000-0002-5077-3736 NR 17 TC 41 Z9 45 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 MAR 25 PY 2006 VL 33 IS 6 AR L06816 DI 10.1029/2005GL025299 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026NH UT WOS:000236345200006 ER PT J AU Sugita, T Nakajima, H Yokota, T Kanzawa, H Gernandt, H Herber, A von der Gathen, P Konig-Langlo, G Sato, K Dorokhov, V Yushkov, VA Murayama, Y Yamamori, M Godin-Beekmann, S Goutail, F Roscoe, HK Deshler, T Yela, M Taalas, P Kyro, E Oltmans, SJ Johnson, BJ Allaart, M Litynska, Z Klekociuk, A Andersen, SB Braathen, GO De Backer, H Randall, CE Bevilacqua, RM Taha, G Thomason, LW Irie, H Ejiri, MK Saitoh, N Tanaka, T Terao, Y Kobayashi, H Sasano, Y AF Sugita, T Nakajima, H Yokota, T Kanzawa, H Gernandt, H Herber, A von der Gathen, P Konig-Langlo, G Sato, K Dorokhov, V Yushkov, VA Murayama, Y Yamamori, M Godin-Beekmann, S Goutail, F Roscoe, HK Deshler, T Yela, M Taalas, P Kyro, E Oltmans, SJ Johnson, BJ Allaart, M Litynska, Z Klekociuk, A Andersen, SB Braathen, GO De Backer, H Randall, CE Bevilacqua, RM Taha, G Thomason, LW Irie, H Ejiri, MK Saitoh, N Tanaka, T Terao, Y Kobayashi, H Sasano, Y TI Ozone profiles in the high-latitude stratosphere and lower mesosphere measured by the Improved Limb Atmospheric Spectrometer (ILAS)-II: Comparison with other satellite sensors and ozonesondes SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ARCTIC WINTER; ILAS; VALIDATION; ASSIMILATION; PERFORMANCE; INSTRUMENT; SYSTEM; TRENDS; HOLE AB [1] A solar occultation sensor, the Improved Limb Atmospheric Spectrometer (ILAS)-II, measured 5890 vertical profiles of ozone concentrations in the stratosphere and lower mesosphere and of other species from January to October 2003. The measurement latitude coverage was 54 - 71 degrees N and 64 - 88 degrees S, which is similar to the coverage of ILAS ( November 1996 to June 1997). One purpose of the ILAS-II measurements was to continue such high-latitude measurements of ozone and its related chemical species in order to help accurately determine their trends. The present paper assesses the quality of ozone data in the version 1.4 retrieval algorithm, through comparisons with results obtained from comprehensive ozonesonde measurements and four satellite-borne solar occultation sensors. In the Northern Hemisphere (NH), the ILAS-II ozone data agree with the other data within +/- 10% ( in terms of the absolute difference divided by its mean value) at altitudes between 11 and 40 km, with the median coincident ILAS-II profiles being systematically up to 10% higher below 20 km and up to 10% lower between 21 and 40 km after screening possible suspicious retrievals. Above 41 km, the negative bias between the NH ILAS-II ozone data and the other data increases with increasing altitude and reaches 30% at 61 - 65 km. In the Southern Hemisphere, the ILAS-II ozone data agree with the other data within +/- 10% in the altitude range of 11 - 60 km, with the median coincident profiles being on average up to 10% higher below 20 km and up to 10% lower above 20 km. Considering the accuracy of the other data used for this comparative study, the version 1.4 ozone data are suitably used for quantitative analyses in the high-latitude stratosphere in both the Northern and Southern Hemisphere and in the lower mesosphere in the Southern Hemisphere. C1 Natl Inst Environm Studies, Tsukuba, Ibaraki 3050053, Japan. Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. Danish Metrol Inst, DK-2100 Copenhagen, Denmark. USN, Res Lab, Remote Sensing Phys Branch, Washington, DC 20375 USA. Norwegian Inst Air Res, N-2027 Kjeller, Norway. Royal Meteorol Soc, B-1000 Brussels, Belgium. Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA. Cent Aerol Observ, Dolgoprudnyi 141700, Russia. Utah State Univ, Ctr Atmospher & Space Sci, Logan, UT 84322 USA. Alfred Wegener Inst Polar & Marine Res, D-27515 Bremerhaven, Germany. CNRS, F-75252 Paris, France. Japan Agcy Marine Earth Sci & Technol, Frontier Res Ctr Global Change, Yokohama, Kanagawa 2360001, Japan. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. Nagoya Univ, Grad Sch Environm Studies, Nagoya, Aichi 4648601, Japan. Australian Antarctic Div, Kingston, Tas 7050, Australia. Cent Res Inst Elect Power Ind, Chiyoda Ku, Tokyo 1008126, Japan. Finnish Meteorol Inst, FI-99600 Sodankyla, Finland. Inst Meteorol & Water Management, PL-05119 Legionowo, Poland. Natl Inst Informat & Commun Technol, Tokyo 1848795, Japan. Natl Inst Environm Studies, Tsukuba, Ibaraki 3050053, Japan. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. British Antarctic Survey, NERC, Cambridge CB3 0ET, England. Univ Tokyo, Ctr Climate Syst Res, Kashiwa, Chiba 2778568, Japan. Natl Inst Polar Res, Tokyo 1738515, Japan. Finnish Meteorol Inst, FI-00101 Helsinki, Finland. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Alfred Wegener Inst Polar & Marine Res, D-14473 Potsdam, Germany. Inst Nacl Tecn Aerospacial, E-28850 Madrid, Spain. RP Natl Inst Environm Studies, Tsukuba, Ibaraki 3050053, Japan. EM tsugita@nies.go.jp RI Sasano, Yasuhiro/C-2927-2009; Yela, Margarita/J-7346-2016; Randall, Cora/L-8760-2014; Klekociuk, Andrew/A-4498-2015; Terao, Yukio/A-2099-2008; von der Gathen, Peter/B-8515-2009; andersen, signe/C-4809-2013; Satoh, Kaoru/P-2047-2015; Konig-Langlo, Gert/K-5048-2012 OI Sasano, Yasuhiro/0000-0001-7470-5642; Yela, Margarita/0000-0003-3775-3156; Randall, Cora/0000-0002-4313-4397; Klekociuk, Andrew/0000-0003-3335-0034; Sato, Kaoru/0000-0002-6225-6066; Terao, Yukio/0000-0003-2345-7073; von der Gathen, Peter/0000-0001-7409-1556; andersen, signe/0000-0002-8216-0141; Konig-Langlo, Gert/0000-0002-6100-4107 NR 34 TC 20 Z9 21 U1 0 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 MAR 24 PY 2006 VL 111 IS D11 AR D11S02 DI 10.1029/2005JD006439 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 026NQ UT WOS:000236346200001 ER PT J AU Kasper, JC Lazarus, AJ Steinberg, JT Ogilvie, KW Szabo, A AF Kasper, JC Lazarus, AJ Steinberg, JT Ogilvie, KW Szabo, A TI Physics-based tests to identify the accuracy of solar wind ion measurements: A case study with the Wind Faraday Cups SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PROTON TEMPERATURE ANISOTROPY; PLASMA PARAMETERS; ELECTRON PARAMETERS; THERMAL NOISE; IONIZED GAS; MINOR IONS; INSTABILITY; MAGNETOSHEATH; SPACECRAFT; ULYSSES AB We present techniques for comparing measurements of velocity, temperature, and density with constraints imposed by the plasma physics of magnetized bi-Maxwellian ions. Deviations from these physics-based constraints are interpreted as arising from measurement errors. Two million ion spectra from the Solar Wind Experiment Faraday Cup instruments on the Wind spacecraft are used as a case study. The accuracy of velocity measurements is determined by the fact that differential flow between hydrogen and helium should be aligned with the ambient magnetic field. Modeling the breakdown of field alignment suggests velocity uncertainties are less than 0.16% in magnitude and 3 degrees in direction. Temperature uncertainty is found by examining the distribution of observed temperature anisotropies in high-beta solar wind intervals where the firehose, mirror, and cyclotron microinstabilities should drive the distribution to isotropy. The presence of a finite anisotropy at high beta suggests overall temperature uncertainties of 8%. Hydrogen and helium number densities are compared with the electron density inferred from observations of the local electron plasma frequency as a function of solar wind speed and year. We find that after accounting for the contribution of minor ions, the results are consistent with a systematic offset between the two instruments of 3-4%. The temperature and density methods are sensitive to non-Maxwellian features such as heat flux and proton beams and as a result are more suited to slow solar wind where these features are rare. These procedures are of general use in identifying the accuracy of observations from any solar wind ion instrument. C1 MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kasper, JC (reprint author), MIT, Kavli Inst Astrophys & Space Res, Bldg 37-673,77 Massachusetts Ave, Cambridge, MA 02139 USA. EM jck@mit.edu RI Kasper, Justin/D-1152-2010 OI Kasper, Justin/0000-0002-7077-930X NR 51 TC 40 Z9 40 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 MAR 24 PY 2006 VL 111 IS A3 AR A03105 DI 10.1029/2005JA011442 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026OQ UT WOS:000236349000002 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 Gravitational-wave extraction from an inspiraling configuration of merging black holes SO PHYSICAL REVIEW LETTERS LA English DT Article ID ADAPTIVE MESH REFINEMENT AB We present new ideas for evolving black holes through a computational grid without excision, which enable accurate and stable evolutions of binary black hole systems with the accurate determination of gravitational waveforms directly from the wave zone region. Rather than excising the black hole interiors, our approach follows the "puncture" treatment of black holes, but utilizing a new gauge condition which allows the black holes to move successfully through the computational domain. We apply these techniques to an inspiraling binary, modeling the radiation generated during the final plunge and ringdown. We demonstrate convergence of the waveforms and good conservation of mass-energy, with just over 3% of the system's mass converted to gravitational radiation. 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 16 TC 612 Z9 613 U1 3 U2 15 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 MAR 24 PY 2006 VL 96 IS 11 AR 111102 DI 10.1103/PhysRevLett.96.111102 PG 4 WC Physics, Multidisciplinary SC Physics GA 025FE UT WOS:000236249900011 PM 16605809 ER PT J AU Bindschadler, R AF Bindschadler, R TI Climate change - Hitting the ice sheets where it hurts SO SCIENCE LA English DT Editorial Material ID PINE ISLAND GLACIER; WEST ANTARCTICA; ACCELERATION; OCEAN C1 NASA, Hydrospher & Biospher Sci Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Bindschadler, R (reprint author), NASA, Hydrospher & Biospher Sci Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM robert.a.bindschadler@nasa.gov NR 20 TC 43 Z9 44 U1 0 U2 5 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 MAR 24 PY 2006 VL 311 IS 5768 BP 1720 EP 1721 DI 10.1126/science.1125226 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 024OA UT WOS:000236204300026 PM 16556828 ER PT J AU Velicogna, I Wahr, J AF Velicogna, I Wahr, J TI Measurements of time-variable gravity show mass loss in Antarctica SO SCIENCE LA English DT Article ID CLIMATE EXPERIMENT; GRACE; RECOVERY AB Using measurements of time-variable gravity from the Gravity Recovery and Climate Experiment satellites, we determined mass variations of the Antarctic ice sheet during 2002-2005. We found that the mass of the ice sheet decreased significantly, at a rate of 152 +/- 80 cubic kilometers of ice per year, which is equivalent to 0.4 +/- 0.2 millimeters of global sea-level rise per year. Most of this mass loss came from the West Antarctic Ice Sheet. C1 Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Wahr, J (reprint author), Univ Colorado, Cooperat Inst Res Environm Sci, Campus Box 390, Boulder, CO 80309 USA. EM isabella@colorado.edu; wahr@colorado.edu NR 16 TC 316 Z9 342 U1 5 U2 43 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD MAR 24 PY 2006 VL 311 IS 5768 BP 1754 EP 1756 DI 10.1126/science.1123785 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 024OA UT WOS:000236204300038 PM 16513944 ER PT J AU Manney, GL Livesey, NJ Jimenez, CJ Pumphrey, HC Santee, ML MacKenzie, IA Waters, JW AF Manney, GL Livesey, NJ Jimenez, CJ Pumphrey, HC Santee, ML MacKenzie, IA Waters, JW TI EOS Microwave Limb Sounder observations of "frozen-in'' anticyclonic air in arctic summer SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID STRATOSPHERE AB A previously unreported phenomenon, a "frozen-in'' anticyclone (FrIAC) after the 2005 Arctic spring vortex breakup, was discovered in Earth Observing System (EOS) Microwave Limb Sounder (MLS) long-lived trace gas data. A tongue of low-latitude (high-N2O, low-H2O) air was drawn into high latitudes and confined in a tight anticyclone, then advected intact in the summer easterlies through late August. A similar feature in O-3 disappeared by early April as a result of chemical processes. The FrIAC was initially advected upright at nearly the same speed at all levels from similar to 660 to 1300 K ( similar to 25 - 45 km); increasing vertical wind shear after early June tilted the FrIAC and weakened it at higher levels. The associated feature in PV disappeared by early June; transport calculations fail to reproduce the remarkable persistence of the FrIAC, suggesting deficiencies in summer high-latitude winds. The historical PV record suggests that this phenomenon may have occurred several times before. The lack of a persistent signature in O3 or PV, along with its small size and rapid motion, make it unlikely that a FrIAC could have been reliably identified without hemispheric daily long-lived trace gas profiles such as those from EOS MLS. C1 New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Edinburgh, Sch Geosci, Edinburgh EH9 3JN, Midlothian, Scotland. RP Manney, GL (reprint author), New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. EM manney@mls.jpl.nasa.gov RI mackenzie, ian/E-9320-2013 NR 12 TC 22 Z9 22 U1 0 U2 4 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 MAR 23 PY 2006 VL 33 IS 6 AR L06810 DI 10.1029/2005GL025418 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026NE UT WOS:000236344900007 ER PT J AU Smith, JA Ackerman, AS Jensen, EJ Toon, OB AF Smith, JA Ackerman, AS Jensen, EJ Toon, OB TI Role of deep convection in establishing the isotopic composition of water vapor in the tropical transition layer SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID STRATOSPHERE-TROPOSPHERE EXCHANGE; TROPOPAUSE LAYER; TRANSPORT; MODEL; CIRRUS; PRECIPITATION; DEHYDRATION; SIMULATION; DEUTERIUM; AEROSOLS AB The transport of H2O and HDO within deep convection is investigated with 3- D large eddy simulations ( LES) using bin microphysics. The lofting and sublimation of HDO- rich ice invalidate the Rayleigh fractionation model of isotopologue distribution within deep convection. Bootstrapping the correlation of the ratio of HDO to H2O ( delta D) to water vapor mixing ratio ( q(v)) through a sequence of convective events produces non- Rayleigh correlations resembling observations. These results support two mechanisms for stratospheric entry. Deep convection can inject air with water vapor of stratospheric character directly into the tropical transition layer ( TTL). Alternatively, moister air detraining from convection may be dehydrated via cirrus formation in the TTL to produce stratospheric water vapor. Significant production of subsaturated air in the TTL via convective dehydration is not observed in these simulations, nor is it necessary to resolve the stratospheric isotope paradox. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. NASA, Ames Res Ctr, Div Earth Sci, Moffett Field, CA 94035 USA. Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. RP Univ Colorado, Atmospher & Space Phys Lab, Campus Box 392, Boulder, CO 80309 USA. EM jamisons@lasp.colorado.edu RI Ackerman, Andrew/D-4433-2012 OI Ackerman, Andrew/0000-0003-0254-6253 NR 33 TC 27 Z9 27 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 MAR 23 PY 2006 VL 33 IS 6 AR L06812 DI 10.1029/2005GL024078 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026NE UT WOS:000236344900001 ER PT J AU Huete, AR Didan, K Shimabukuro, YE Ratana, P Saleska, SR Hutyra, LR Yang, WZ Nemani, RR Myneni, R AF Huete, AR Didan, K Shimabukuro, YE Ratana, P Saleska, SR Hutyra, LR Yang, WZ Nemani, RR Myneni, R TI Amazon rainforests green-up with sunlight in dry season SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TROPICAL FOREST; VEGETATION DYNAMICS; CO2 EXCHANGE; CARBON; FLUXES; PHENOLOGY; CLIMATE; TREES; MODIS; WATER AB Metabolism and phenology of Amazon rainforests significantly influence global dynamics of climate, carbon and water, but remain poorly understood. We analyzed Amazon vegetation phenology at multiple scales with Moderate Resolution Imaging Spectroradiometer ( MODIS) satellite measurements from 2000 to 2005. MODIS Enhanced Vegetation Index (EVI, an index of canopy photosynthetic capacity) increased by 25% with sunlight during the dry season across Amazon forests, opposite to ecosystem model predictions that water limitation should cause dry season declines in forest canopy photosynthesis. In contrast to intact forests, areas converted to pasture showed dry-season declines in EVI-derived photosynthetic capacity, presumably because removal of deep-rooted forest trees reduced access to deep soil water. Local canopy photosynthesis measured from eddy flux towers in both a rainforest and forest conversion site confirm our interpretation of satellite data, and suggest that basin-wide carbon fluxes can be constrained by integrating remote sensing and local flux measurements. C1 Univ Arizona, Dept Soil Water & Environm Sci, Tucson, AZ 85721 USA. Univ Arizona, Inst Study Planet Earth, Tucson, AZ 85721 USA. Inst Nacl Pesquisas Espaciais, BR-12227010 Sao Jose Dos Campos, Brazil. Univ Arizona, Dept Ecol & Evolutionary Biol, Tucson, AZ 85721 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. Boston Univ, Dept Geog, Boston, MA 02215 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Univ Arizona, Dept Soil Water & Environm Sci, 429 Shantz Bldg 38, Tucson, AZ 85721 USA. EM ahuete@ag.arizona.edu RI Mitchard, Edward/C-6346-2009; Yang, Wenze/B-8356-2012; Myneni, Ranga/F-5129-2012; Huete, Alfredo/C-1294-2008; OI Yang, Wenze/0000-0001-8514-2742; Huete, Alfredo/0000-0003-2809-2376; Ratana, Piyachat/0000-0002-1853-2860 NR 31 TC 282 Z9 293 U1 10 U2 85 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 MAR 22 PY 2006 VL 33 IS 6 AR L06405 DI 10.1029/2005GL025583 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026ND UT WOS:000236344800009 ER PT J AU Chylek, P Dubey, MK Lohmann, U Ramanathan, V Kaufman, YJ Lesins, G Hudson, J Altmann, G Olsen, S AF Chylek, P Dubey, MK Lohmann, U Ramanathan, V Kaufman, YJ Lesins, G Hudson, J Altmann, G Olsen, S TI Aerosol indirect effect over the Indian Ocean SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GLOBAL RADIATION BUDGET; CIRRUS CLOUDS; CLIMATE; PARTICLES AB We analyze the MODIS (Moderate Resolution Imaging Spectroradiometer) satellite data over the seas adjacent to the Indian sub-continent to investigate the effect of aerosols on the size distribution of cloud droplets and ice crystals (indirect aerosol effect). During the winter months of increased anthropogenic pollution we observe smaller sizes of cloud droplets in water clouds in agreement with the expected aerosol indirect effect. However, contrary to our expectations, we find that during episodes of increased pollution the effective radius of ice crystals is shifted toward the larger rather than smaller sizes. We propose a combination of natural seasonal variability of meteorological conditions and an "inverse aerosol indirect effect" caused by heterogeneous ice nucleation as a possible explanation of observed ice crystal growth. The ECHAM4 (European Center for Medium-Range Weather Forecast Hamburg version 4th generation GCM) results with heterogeneous ice nucleation reproduce the observed increase in ice crystal size during the enhanced pollution episodes. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. ETH, Inst Atmospher & Climate Sci, CH-8057 Zurich, Switzerland. Univ Calif San Diego, Scripps Inst Oceanog, Ctr Atmospher Sci, La Jolla, CA 92037 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Dalhousie Univ, Dept Phys & Atmospher Sci, Halifax, NS B3H 3J5, Canada. Univ Nevada, Desert Res Inst, Reno, NV 89507 USA. RP Chylek, P (reprint author), Los Alamos Natl Lab, MS B244, Los Alamos, NM 87545 USA. EM chylek@lanl.gov RI Dubey, Manvendra/E-3949-2010; Lohmann, Ulrike/B-6153-2009 OI Dubey, Manvendra/0000-0002-3492-790X; Lohmann, Ulrike/0000-0001-8885-3785 NR 16 TC 40 Z9 42 U1 0 U2 6 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 MAR 21 PY 2006 VL 33 IS 6 AR L06806 DI 10.1029/2005GL025397 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026NC UT WOS:000236344700004 ER PT J AU Joiner, J Vasilkov, A Yang, K Bhartia, PK AF Joiner, J Vasilkov, A Yang, K Bhartia, PK TI Observations over hurricanes from the ozone monitoring instrument SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TROPICAL CYCLONES; RAMAN-SCATTERING; RETRIEVALS AB There is an apparent inconsistency between the total column ozone derived from the total ozone mapping spectrometer ( TOMS) and aircraft observations within the eye region of tropical cyclones. The higher spectral resolution, coverage, and sampling of the ozone monitoring instrument (OMI) on NASA's Aura satellite as compared with TOMS allows for improved ozone retrievals by including estimates of cloud pressure derived simultaneously using the effects of rotational Raman scattering. The retrieved cloud pressures are more appropriate than the climatological cloud-top pressures based on infrared measurements used in the TOMS and initial OMI algorithms. We find that total ozone within the eye of hurricanes Katrina and Rita is significantly overestimated when we use climatological cloud pressures. The cloud-corrected total ozone is in better agreement with aircraft measurements that imply relatively small or negligible amounts of stratospheric intrusion into the eye region. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD USA. RP Joiner, J (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613-3, Greenbelt, MD 20771 USA. EM joanna.joiner@nasa.gov RI Joiner, Joanna/D-6264-2012; Bhartia, Pawan/A-4209-2016 OI Bhartia, Pawan/0000-0001-8307-9137 NR 16 TC 12 Z9 13 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 MAR 21 PY 2006 VL 33 IS 6 AR L06807 DI 10.1029/2005GL025592 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026NC UT WOS:000236344700008 ER PT J AU Zhang, PJ Pen, UL AF Zhang, PJ Pen, UL TI Precision measurement of cosmic magnification from 21-cm emitting galaxies SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : abundances; large-scale structure of Universe; radio lines : galaxies ID LARGE-SCALE STRUCTURE; 3-DIMENSIONAL POWER SPECTRUM; WEAK LENSING STATISTICS; LYMAN-ALPHA ABSORBERS; DIGITAL SKY SURVEY; COSMOLOGICAL PARAMETERS; QUASAR-GALAXY; SHEAR; EVOLUTION; PROBE AB We show how precision lensing measurements can be obtained through the lensing magnification effect in high-redshift 21-cm emission from galaxies. Previously, cosmic magnification measurements have been seriously complicated by galaxy clustering. With precise redshifts obtained using the 21-cm emission line wavelength, one can correlate galaxies at different source planes, or exclude close pairs to eliminate such contamination. We provide forecasts for future surveys, specifically the Square Kilometer Array (SKA) and the Canadian Large Adaptive Reflector (CLAR). SKA can achieve similar to 1 per cent precision on the dark-matter power spectrum and the galaxy dark-matter cross-correlation power spectrum, while CLAR can measure an accurate cross-correlation power spectrum. The neutral hydrogen fraction was most likely significantly higher at high redshifts, which increases the number of observed galaxies significantly, such that CLAR can also measure the dark-matter lensing power spectrum. SKA can also allow precise measurement of bispectrum lensing. C1 NASA, Fermilab Astrophys Grp, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. RP Zhang, PJ (reprint author), NASA, Fermilab Astrophys Grp, Fermi Natl Accelerator Lab, Box 500, Batavia, IL 60510 USA. EM pjzhang@shao.ac.cn; pen@cita.utoronto.ca RI ZHANG, PENGJIE/O-2825-2015 NR 45 TC 26 Z9 27 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 MAR 21 PY 2006 VL 367 IS 1 BP 169 EP 178 DI 10.1111/j.1365-2966.2006.09971.x PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 020VA UT WOS:000235939700029 ER PT J AU Fender, RP Muxlow, TWB Garrett, MA Kouveliotou, C Gaensler, BM Garrington, ST Paragi, Z Tudose, V Miller-Jones, JCA Spencer, RE AF Fender, RP Muxlow, TWB Garrett, MA Kouveliotou, C Gaensler, BM Garrington, ST Paragi, Z Tudose, V Miller-Jones, JCA Spencer, RE TI Structure in the radio counterpart to the 2004 December 27 giant flare from SGR 1806-20 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE pulsars : individual : SGR1806-20; ISM : jets and outflows; radio continuum : stars ID MAGNETAR SGR-1806-20; DISTANCE; PULSAR; NEBULA; JETS AB On 2004 December 27, the magnetar SGR 1806-20 underwent an enormous outburst resulting in the formation of an expanding, moving, and fading radio source. We report observations of this radio source with the Multi-Element Radio-Linked Interferometer Network and the Very Long Baseline Array. The observations confirm the elongation and expansion already reported based on observations at lower angular resolutions, but suggest that at early epochs the structure is not consistent with the very simplest models such as a smooth flux distribution. In particular, there appears to be significant structure on small angular scales, with similar to 10 per cent of the radio flux arising on angular scales <= 100 milliarcsec. This structure may correspond to localized sites of particle acceleration during the early phases of expansion and interaction with the ambient medium. C1 Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. Joint Inst VLBI Europe, NL-7990 AA Dwingeloo, Netherlands. NASA, George C Marshall Space Flight Ctr, NSSTC, Huntsville, AL 35805 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Romanian Acad, Inst Astron, RO-040557 Bucharest, Romania. Kavli Inst Particle Astrophys & Cosmol, Menlo Pk, CA 94025 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. RP Fender, RP (reprint author), Univ Southampton, Sch Phys & Astron, Highfield, Southampton SO17 1BJ, Hants, England. EM rpf@phys.soton.ac.uk RI Gaensler, Bryan/F-8655-2010; Tudose, Valeriu/F-8976-2010; Miller-Jones, James/B-2411-2013; OI Miller-Jones, James/0000-0003-3124-2814; Muxlow, Thomas/0000-0001-5797-8796; Wijers, Ralph/0000-0002-3101-1808; Gaensler, Bryan/0000-0002-3382-9558 NR 23 TC 8 Z9 8 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 MAR 21 PY 2006 VL 367 IS 1 BP L6 EP L10 DI 10.1111/j.1745-3933.2006.00123.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 020VA UT WOS:000235939700002 ER PT J AU Kumar, P McMahon, E Barthelmy, SD Burrows, D Gehrels, N Goad, M Nousek, J Tagliaferri, G AF Kumar, P McMahon, E Barthelmy, SD Burrows, D Gehrels, N Goad, M Nousek, J Tagliaferri, G TI A unified picture for gamma-ray burst prompt and X-ray afterglow emissions SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE hydrodynamics; shock waves; gamma-rays : bursts AB Data from the Swift satellite have enabled us for the first time to provide a complete picture of the gamma-ray (gamma-ray) burst emission mechanism and its relationship with the early afterglow emissions. We show that gamma-ray photons for two bursts, 050126 and 050219A, for which we have carried out detailed analysis were produced as a result of the synchrotron self-Compton process in the material ejected in the explosion when it was heated to a mildly relativistic temperature at a distance from the centre of explosion of order the deceleration radius. Both of these bursts exhibit rapidly declining early X-ray afterglow light curves; this emission is from the same source that produced the gamma-ray burst. The technique that we exploit to determine this is very general and makes no assumption about any particular model for gamma-ray generation except that the basic radiation mechanism is some combination of synchrotron and inverse Compton processes in a relativistic outflow. For GRB 050219A we can rule out the possibility that energy from the explosion is carried outward by magnetic fields, and that the dissipation of this field produced the gamma-ray burst. C1 Univ Texas, Dept Astron, Austin, TX 78712 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. INAF, Osservatorio Astron Brera, I-23807 Merate, LC, Italy. RP Kumar, P (reprint author), Univ Texas, Dept Astron, Austin, TX 78712 USA. EM pk@astro.as.utexas.edu RI Gehrels, Neil/D-2971-2012; Barthelmy, Scott/D-2943-2012; OI Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 14 TC 14 Z9 14 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 MAR 21 PY 2006 VL 367 IS 1 BP L52 EP L56 DI 10.1111/j.1745-3933.2006.00138.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 020VA UT WOS:000235939700012 ER PT J AU Miller, MC AF Miller, MC TI Constraints on alternatives to supermassive black holes SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE gravitation; black hole physics; Galaxy : centre; Galaxy : nucleus; galaxies : kinematics and dynamics ID SAGITTARIUS-A-ASTERISK; GALACTIC-CENTER; DYNAMICAL EVOLUTION; PRIMORDIAL BINARIES; CLUSTER EVOLUTION; STELLAR DYNAMICS; STAR-CLUSTERS; MASS; SIMULATIONS; SYSTEMS AB Observations of the centres of galaxies continue to evolve, and it is useful to take a fresh look at the constraints that exist on alternatives to supermassive black holes at their centres. We discuss constraints complementary to those of Maoz and demonstrate that an extremely wide range of other possibilities can be excluded. In particular, we present the new argument that for the velocity dispersions inferred for many galactic nuclei, even binaries made of point masses cannot stave off core collapse because hard binaries are so tight that they merge via emission of gravitational radiation before they can engage in three-body or four-body interactions. We also show that under these conditions core collapse leads inevitably to runaway growth of a central black hole with a significant fraction of the initial mass, regardless of the masses of the individual stars. For clusters of non-interacting low-mass objects (from low-mass stars to elementary particles), the relaxation of stars and compact objects that pass inside the dark region will be accelerated by interactions with the dark mass. If the dark region is instead a self-supported object, such as a fermion ball, then if stellar-mass black holes exist they will collide with the object, settle, and consume it. The net result is that the keyhole through which alternatives to supermassive black holes must pass is substantially smaller and more contrived than it was even a few years ago. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Miller, MC (reprint author), Univ Maryland, Dept Astron, College Pk, MD 20742 USA. EM miller@astro.umd.edu NR 28 TC 15 Z9 15 U1 0 U2 2 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 MAR 21 PY 2006 VL 367 IS 1 BP L32 EP L36 DI 10.1111/j.1745-3933.2006.00135.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 020VA UT WOS:000235939700008 ER PT J AU Unger, N Shindell, DT Koch, DM Streets, DG AF Unger, N Shindell, DT Koch, DM Streets, DG TI Cross influences of ozone and sulfate precursor emissions changes on air quality and climate SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE air pollution; climate change; aerosols; greenhouse gases ID TROPOSPHERIC OZONE; POLLUTION; MODEL; SIMULATIONS; AEROSOLS AB Tropospheric O-3 and sulfate both contribute to air pollution and climate forcing. There is a growing realization that air quality and climate change issues are strongly connected. To date, the importance of the coupling between O-3 and sulfate has not been fully appreciated, and thus regulations treat each pollutant separately. We show that emissions of O-3 precursors can dramatically affect regional sulfate air quality and climate forcing. At 2030 in an A1B future, increased O-3 precursor emissions enhance surface sulfate over India and China by up to 20% because of increased levels of OH and gas-phase SO2 oxidation rates and add up to 20% to the direct sulfate forcing for that region relative to the present day. Hence, O-3 precursors impose an indirect forcing via sulfate, which is more than twice the direct O-3 forcing itself (compare -0.61 vs. + 0.35 W/m(2)). Regulatory policy should consider both air quality and climate and should address O-3 and sulfate simultaneously because of the strong interaction between these species. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, New York, NY 10025 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Unger, N (reprint author), NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM nunger@giss.nasa.gov RI Shindell, Drew/D-4636-2012; Unger, Nadine/M-9360-2015; OI Streets, David/0000-0002-0223-1350 NR 25 TC 48 Z9 50 U1 1 U2 9 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 MAR 21 PY 2006 VL 103 IS 12 BP 4377 EP 4380 DI 10.1073/pnas.0508769103 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 026SN UT WOS:000236362600012 PM 16537360 ER PT J AU Johnson, WR Wilson, DW Bearman, G AF Johnson, WR Wilson, DW Bearman, G TI Spatial-spectral modulating snapshot hyperspectral imager SO APPLIED OPTICS LA English DT Article ID TOMOGRAPHY IMAGING SPECTROMETER; SIMULTANEOUS ACQUISITION; FOURIER CROSSTALK; INFORMATION; MATRIX AB Experimental results are presented for a computed tomography imaging spectrometer (CTIS) with imposed spatial-spectral modulation on the image scene. This modulation structure on the CTIS tomographic dispersion created substantial gains in spectral reconstruction resolution after standard iterative, nonlinear, inversion techniques were used. Modulation limits system ambiguities, so high-frequency spectral and low-frequency spatial scene data could be recovered. The results demonstrate how spatial modulation acts as a high-frequency spectral deconvolver for the snapshot hyperspectral imager technology. (c) 2006 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Johnson, WR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM william.r.johnson@jpl.nasa.gov NR 34 TC 21 Z9 22 U1 0 U2 8 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 MAR 20 PY 2006 VL 45 IS 9 BP 1898 EP 1908 DI 10.1364/AO.45.001898 PG 11 WC Optics SC Optics GA 026XN UT WOS:000236376700002 PM 16579558 ER PT J AU Steele, HM Eldering, A Lumpe, JD AF Steele, HM Eldering, A Lumpe, JD TI Simulations of the accuracy in retrieving stratospheric aerosol effective radius, composition, and loading from infrared spectral transmission measurements SO APPLIED OPTICS LA English DT Article ID SAGE III WAVELENGTHS; EXTINCTION MEASUREMENTS; SIZE DISTRIBUTIONS; ERROR ANALYSIS; INTEGRAL PROPERTIES; OPTICAL-MODEL; POAM II; SATELLITE; ALGORITHM; INVERSION AB We examine the extent to which three physical aerosol parameters-effective radius, composition (sulfate weight percent), and total volume-can be determined from infrared transmission spectra. Using simulated transmission data over the range 800-4750 cm(-1)(12.5-2.1 mu m) and errors taken from the infrared spectral measurements of the Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument, we use optimal estimation to recover these aerosol parameters. Uncertainties in these are examined as a function of the size, composition, and loading of stratospheric aerosols and of the spectral range employed. Using the entire spectral range above, we retrieve all three parameters with a precision to within 3% if the size distribution form is known. Additional errors result, however, from an uncertainty in the size distribution width. These are small (only a few percent) for composition and total volume but are substantial (as much as 50%) for effective radius. Errors also increase substantially when the spectral range is reduced. The retrieved effective radius can have an error of 100% or greater for typical stratospheric aerosol sizes when the spectral range is restricted to the lower wavenumber part of the range. For good accuracy in effective radius, the spectral range must extend beyond similar to 3000 cm(-1). Composition and total volume are less sensitive to the spectral range than effective radius. These simulations were carried out with modeled data to test the potential accuracy of stratospheric sulfate aerosol retrievals from the Atmospheric Chemistry Experiment (ACE). Because of the limitations that result from the use of simulated data, we have tested our retrieval algorithm using ATMOS spectra in different filter regions and present here the aerosol parameters obtained. (c) 2006 Optical Society of America. C1 Calif State Univ Northridge, Dept Geog, Northridge, CA 91330 USA. Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90024 USA. Jet Prop Lab, Pasadena, CA 91109 USA. Computat Phys Inc, Springfield, VA 22151 USA. RP Steele, HM (reprint author), Calif State Univ Northridge, Dept Geog, 18111 Nordhoff St, Northridge, CA 91330 USA. EM helen.m.cox@sun.edu NR 37 TC 7 Z9 7 U1 1 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 MAR 20 PY 2006 VL 45 IS 9 BP 2014 EP 2027 DI 10.1364/AO.45.002014 PG 14 WC Optics SC Optics GA 026XN UT WOS:000236376700016 PM 16579572 ER PT J AU Papovich, C Moustakas, LA Dickinson, M Le Floc'h, E Rieke, GH Daddi, E Alexander, DM Bauer, F Brandt, WN Dahlen, T Egami, E Eisenhardt, P Elbaz, D Ferguson, HC Giavalisco, M Lucas, RA Mobasher, B Perez-Gonzalez, PG Stutz, A Rieke, MJ Yan, H AF Papovich, C Moustakas, LA Dickinson, M Le Floc'h, E Rieke, GH Daddi, E Alexander, DM Bauer, F Brandt, WN Dahlen, T Egami, E Eisenhardt, P Elbaz, D Ferguson, HC Giavalisco, M Lucas, RA Mobasher, B Perez-Gonzalez, PG Stutz, A Rieke, MJ Yan, H TI Spitzer observations of massive, red galaxies at high redshift SO ASTROPHYSICAL JOURNAL LA English DT Review DE cosmology : observations; galaxies : evolution; galaxies : formation; galaxies : high-redshift; galaxies : stellar content; infrared : galaxies ID STAR-FORMING GALAXIES; DEEP-FIELD-SOUTH; LYMAN-BREAK GALAXIES; ULTRAVIOLET LUMINOSITY DENSITY; ULTRALUMINOUS INFRARED GALAXIES; SPECTRAL ENERGY-DISTRIBUTION; ACTIVE GALACTIC NUCLEI; COSMOLOGICAL HYDRODYNAMIC SIMULATIONS; X-RAY SURVEYS; STELLAR MASS AB We study massive galaxies at z similar to 1-3.5 using HST optical imaging, ground-based near-IR imaging, and Spitzer observations at 3-24 mu m. From K-s-selected galaxies in the similar or equal to 130 arcmin(2) GOODS-S field, we identify 153 distant red galaxies ( DRGs) with (J - K-s)(Vega) >= 2.3. This sample is approximately complete in stellar mass for passively evolving galaxies above 10(11) M-circle dot and z <= 3. Roughly half of the DRGs are objects whose optical and near-IR rest-frame light is dominated by evolved stars combined with ongoing star formation ( at z(med) similar to 2: 5), and the others are galaxies whose light is dominated by heavily reddened (A(1600) greater than or similar to 4-6 mag) starbursts (at z(med) similar to 1.7). Very few DRGs (less than or similar to 10%) have no indication of current star formation. DRGs at z similar to 1.5-3 with stellar masses similar to 10(11) M-circle dot have specific star formation rates ( SFRs per unit mass) including the reradiated far-IR emission that range from 0.2 to 10 Gyr(-1). Based on the X-ray luminosities and rest-frame near-IR colors, roughly one-quarter of the DRGs contain AGNs, implying that the growth of supermassive black holes coincides with the formation of massive galaxies. At 1.5 <= z <= 3, the DRGs with M >= 10(11) M-circle dot have an integrated specific SFR comparable to the global value of all galaxies. In contrast, galaxies at z similar to 0.3-0.75 with M >= 10(11) M-circle dot have an integrated specific SFR less than the global value and more than an order of magnitude lower than that for massive DRGs. At z P 1, lower mass galaxies dominate the overall cosmic mass assembly. This suggests that the bulk of star formation in massive galaxies occurs at early cosmic epochs and is largely complete by z similar to 1.5. Further mass assembly in these galaxies takes place with low specific SFRs. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Natl Opt Astron Observ, Tucson, AZ 85721 USA. Associated Observ Paris, GEPI, F-92195 Meudon, France. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden. CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. RP Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM papovich@as.arizona.edu RI Daddi, Emanuele/D-1649-2012; Brandt, William/N-2844-2015; Perez-Gonzalez, Pablo/J-2871-2016; OI Daddi, Emanuele/0000-0002-3331-9590; Brandt, William/0000-0002-0167-2453; Perez-Gonzalez, Pablo/0000-0003-4528-5639; Stutz, Amelia/0000-0003-2300-8200; Moustakas, Leonidas/0000-0003-3030-2360; Alexander, David/0000-0002-5896-6313 NR 158 TC 262 Z9 262 U1 0 U2 10 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 MAR 20 PY 2006 VL 640 IS 1 BP 92 EP 113 DI 10.1086/499915 PN 1 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RE UT WOS:000236143100011 ER PT J AU Piner, BG Bhattarai, D Edwards, PG Jones, DL AF Piner, BG Bhattarai, D Edwards, PG Jones, DL TI The fastest relativistic jets: VLBA observations of blazars with apparent speeds exceeding 25c SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects : individual (0235+164); galaxies : active; galaxies : jets; quasars : individual (0827+243,1406-076); radio continuum : galaxies ID ACTIVE GALACTIC NUCLEI; BASE-LINE ARRAY; KINEMATICS; QUASARS; MOTION AB We have measured peak apparent speeds of 25.6c +/- 7.0c, 25.6c +/- 4.4c, and 28.2c +/- 6.6c in the jets of 0235+164, 0827+243, and 1406-076, respectively, based on six epochs of high-sensitivity VLBA observations at 22 and 43 GHz during 2002 and 2003 (H-0 = 71 km s(-1) Mpc(-1), Omega(m) = 0.27, and Omega(Lambda) = 0.73). These blazars had been identified as potentially having apparent speeds exceeding 40c in an earlier VLBA survey of EGRET blazars by Jorstad and coworkers. We therefore confirm ( with high confidence in 0827+243, and lower confidence in 0235+164 and 1406-076) the presence of highly relativistic pattern speeds in these three jets, although not at the > 40c levels reported by Jorstad and coworkers. The lower limit to the bulk Lorentz factor implied by the observed apparent speeds is Gamma greater than or similar to 25-30 in these three sources, if the pattern speeds are equal to or slower than the bulk flow speed. C1 Whittier Coll, Dept Phys & Astron, Whittier, CA 90608 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. RP Piner, BG (reprint author), Whittier Coll, Dept Phys & Astron, 13406 E Philadelphia St, Whittier, CA 90608 USA. NR 14 TC 24 Z9 24 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 MAR 20 PY 2006 VL 640 IS 1 BP 196 EP 203 DI 10.1086/500006 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RE UT WOS:000236143100018 ER PT J AU Lorimer, DR Stairs, IH Freire, PC Cordes, JM Camilo, F Faulkner, AJ Lyne, AG Nice, DJ Ransom, SM Arzoumanian, Z Manchester, RN Champion, DJ van Leeuwen, J Mclaughlin, MA Ramachandran, R Hessels, JW Vlemmings, W Deshpande, AA Bhat, ND Chatterjee, S Han, JL Gaensler, BM Kasian, L Deneva, JS Reid, B Lazio, TJ Kaspi, VM Crawford, F Lommen, AN Backer, DC Kramer, M Stappers, BW Hobbs, GB Possenti, A D'Amico, N Burgay, M AF Lorimer, DR Stairs, IH Freire, PC Cordes, JM Camilo, F Faulkner, AJ Lyne, AG Nice, DJ Ransom, SM Arzoumanian, Z Manchester, RN Champion, DJ van Leeuwen, J Mclaughlin, MA Ramachandran, R Hessels, JW Vlemmings, W Deshpande, AA Bhat, ND Chatterjee, S Han, JL Gaensler, BM Kasian, L Deneva, JS Reid, B Lazio, TJ Kaspi, VM Crawford, F Lommen, AN Backer, DC Kramer, M Stappers, BW Hobbs, GB Possenti, A D'Amico, N Burgay, M TI Arecibo pulsar survey using ALFA. II. The young, highly relativistic binary pulsar J1906+0746 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : general; pulsars : individual (PSR J1906+0746) ID GEODETIC SPIN PRECESSION; DOUBLE NEUTRON-STARS; RADIO PULSARS; PROBABILITY-DISTRIBUTION; POSSIBLE COMPANIONS; COALESCENCE RATES; PSR J1141-6545; SYSTEM; DISCOVERY; B1913+16 AB We report the discovery of PSR J1906+0746, a young 144 ms pulsar in a highly relativistic 3.98 hr orbit with an eccentricity of 0.085 and expected gravitational wave coalescence time of similar to 300 Myr. The new pulsar was found during precursor survey observations with the Arecibo 1.4 GHz feed array system and retrospectively detected in the Parkes Multibeam plane pulsar survey data. From radio follow-up observations with Arecibo, Jodrell Bank, Green Bank, and Parkes, we have measured the spin-down and binary parameters of the pulsar and its basic spectral and polarization properties. We also present evidence for pulse profile evolution, which is likely due to geodetic precession, a relativistic effect caused by the misalignment of the pulsar spin and total angular momentum vectors. Our measurements show that PSR J1906+0746 is a young object with a characteristic age of 112 kyr. From the measured rate of orbital periastron advance (7 degrees 57 +/- 0 degrees.03 yr(-1)), we infer a total system mass of 2.61 +/- 0: 02 M-circle dot. While these parameters suggest that the PSR J1906+0746 binary system might be a younger version of the double pulsar system, intensive searches for radio pulses from the companion have so far been unsuccessful. It is therefore not known whether the companion is another neutron star or a massive white dwarf. Regardless of the nature of the companion, a simple calculation suggests that the Galactic birthrate of binaries similar to PSR J1906+ 0746 is similar to 60 Myr(-1). This implies that PSR J1906+0746 will make a significant contribution to the computed cosmic inspiral rate of compact binary systems. C1 Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Arecibo Observ, Natl Astron & Ionosphere Ctr, Arecibo, PR 00612 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Bryn Mawr Coll, Dept Phys, Rosemont, PA 19010 USA. Natl Radio Astron Observ, Charlottesville, VA USA. NASA, Goddard Space Flight Ctr, USRA, EUD, Greenbelt, MD 20771 USA. CSIRO, Australia Telescope Natl Facil, Epping, NSW 1710, Australia. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. Swinburne Univ Technol, Ctr Astrophys & Supercomp, Hawthorn, Vic 3122, Australia. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. USN, Res Lab, Washington, DC 20375 USA. Haverford Coll, Dept Phys, Haverford, PA 19041 USA. Franklin & Marshall Coll, Dept Phys & Astron, Lancaster, PA 17604 USA. Stichtung ASTRON, NL-7990 AA Dwingeloo, Netherlands. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Osservatorio Astron Cagliari, Ist Nazl Astrofis, I-09012 Capoterra, Italy. RP Lorimer, DR (reprint author), Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. RI Gaensler, Bryan/F-8655-2010; D'Amico, Nichi/A-5715-2009; Deshpande, Avinash/D-4868-2012; Astronomy & Astrophysics Group, Raman Res Institute/D-4046-2012; Bhat, Ramesh/B-7396-2013 OI Burgay, Marta/0000-0002-8265-4344; Nice, David/0000-0002-6709-2566; Ransom, Scott/0000-0001-5799-9714; /0000-0002-2700-9916; Gaensler, Bryan/0000-0002-3382-9558; NR 50 TC 77 Z9 80 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 MAR 20 PY 2006 VL 640 IS 1 BP 428 EP 434 DI 10.1086/499918 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RE UT WOS:000236143100043 ER PT J AU Ghosh, KK Finger, MH Swartz, DA Tennant, AF Wu, K AF Ghosh, KK Finger, MH Swartz, DA Tennant, AF Wu, K TI On the nature of the ultraluminous X-ray transient in Cen A (NGC 5128) SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (Cen A); X-rays : binaries; X-rays : individual (1RXH J132519.8-430312) ID SOURCE POPULATION; BINARY; PULSAR; CENTAURUS; EMISSION; A0538-66; INSTABILITY; ACCRETION; DISCOVERY; GALAXIES AB We combine nine ROSAT, nine Chandra, and two XMM-Newton observations of the Cen A galaxy to obtain the X-ray light curve of 1RXH J132519.8 - 430312 (= CXOU J132519.9 - 430317) spanning 1990 - 2003. The source reached a peak 0.1 - 2.4 keV flux F-X > 10(-12) ergs cm(-2) s(-1) during a 10 day span in 1995 July. The inferred peak isotropic luminosity of the source therefore exceeded 3 x 10(39) ergs s(-1), which places the source in the class of ultraluminous X-ray sources. Coherent pulsations at 13.264 Hz are detected during a second bright episode (F-X > 3 x 10(-13) ergs cm(-2) s(-1)) in 1999 December. The source is detected and varies significantly within three additional observations but is below the detection threshold in seven observations. The X-ray spectrum in 1999 December is best described as a cutoff power law or a disk blackbody (multicolored disk). We also detect an optical source, m(F555W) similar to 24.1 mag, within the Chandra error circle of 1RXH J132519.8 - 430312 in Hubble Space Telescope images taken 195 days before the nearest X-ray observation. The optical brightness of this source is consistent with a late O or early B star at the distance of Cen A. If the optical source is the counterpart, then the X-ray and optical behavior of 1RXH J132519.8 - 430312 is similar to the transient Be/X- ray pulsar A0538 - 66. C1 NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35805 USA. NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Huntsville, AL 35805 USA. UCL, Mullard Space Sci Lab, Holmbury RH5 6NT, Surrey, England. RP NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, XD12, Huntsville, AL 35805 USA. NR 31 TC 10 Z9 10 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 MAR 20 PY 2006 VL 640 IS 1 BP 459 EP 465 DI 10.1086/498011 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RE UT WOS:000236143100046 ER PT J AU Dullemond, CP Apai, D Walch, S AF Dullemond, CP Apai, D Walch, S TI Crystalline silicates as a probe of disk formation history SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; dust, extinction; planetary systems : formation planetary; systems : protoplanetary disks ID PROTOPLANETARY ACCRETION DISKS; HALE-BOPP; DUST; EVOLUTION; MINERALOGY; DIFFUSION; SYSTEMS; COMETS; MODELS; COMA AB We present a new perspective on the crystallinity of dust in protoplanetary disks. The dominant crystallization by thermal annealing happens in the very early phases of disk formation and evolution. Both the disk properties and the level of crystallinity are thereby directly linked to the properties of the molecular cloud core from which the star + disk system was formed. We show that under the assumption of single-star formation, rapidly rotating clouds produce disks that after the main infall phase (i.e., in the optically revealed class II phase) are rather massive and have a high accretion rate but low crystallinity. Slowly rotating clouds, on the other hand, produce less massive disks with lower accretion rates but high levels of crystallinity. Cloud fragmentation and the formation of multiple stars complicates the problem and necessitates further study. The underlying physics of the model is insufficiently understood to provide the precise relationship between crystallinity, disk mass, and accretion rate. But the fact that with "standard" input physics the model produces disks that, in comparison to observations, appear to have either too high levels of crystallinity or too high disk masses demonstrates that the comparison of these models to observations can place strong constraints on the disk physics. The question to ask is not why some sources are so crystalline, but why some other sources have such a low level of crystallinity. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. NASA, Astrobiol Inst, Ames Res Ctr, Moffett Field, CA 94035 USA. Uni Sternwarte Munchen, D-81679 Munich, Germany. RP Dullemond, CP (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. EM dullemon@mpia.de OI Dullemond, Cornelis/0000-0002-7078-5910 NR 22 TC 41 Z9 41 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 MAR 20 PY 2006 VL 640 IS 1 BP L67 EP L70 DI 10.1086/503100 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RG UT WOS:000236143300017 ER PT J AU Kashlinsky, A AF Kashlinsky, A TI Cosmic infrared background from population III stars and its effect on spectra of high-z gamma-ray bursts (vol 633, pg L5, 2005) SO ASTROPHYSICAL JOURNAL LA English DT Correction C1 NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Greenbelt, MD 20771 USA. RP Kashlinsky, A (reprint author), NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Code 665, Greenbelt, MD 20771 USA. EM kashlinsky@stars.gsfc.nasa.gov NR 1 TC 1 Z9 1 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 MAR 20 PY 2006 VL 640 IS 1 BP L109 EP L109 DI 10.1086/503296 PN 2 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RG UT WOS:000236143300028 ER PT J AU Nota, A Sirianni, M Sabbi, E Tosi, M Clampin, M Gallagher, J Meixner, M Oey, MS Pasquali, A Smith, LJ Walterbos, R Mack, J AF Nota, A Sirianni, M Sabbi, E Tosi, M Clampin, M Gallagher, J Meixner, M Oey, MS Pasquali, A Smith, LJ Walterbos, R Mack, J TI Discovery of a population of pre-main-sequence stars in NGC 346 from deep Hubble Space Telescope ACS images SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : star clusters; Magellanic Clouds; open clusters and associations : individual (NGC 346); stars : evolution; stars : pre-main-sequence ID SMALL-MAGELLANIC-CLOUD; O-STARS; SMC; SPECTROSCOPY; ISOCHRONES; DATABASE; TRACKS; N66 AB We report the discovery of a rich population of low-mass stars in the young, massive NGC 346 star-forming region in the Small Magellanic Cloud from deep V, I, and H alpha images taken with the Hubble Space Telescope Advanced Camera for Surveys. These stars have likely formed together with the NGC 346 cluster, similar or equal to 3-5 Myr ago. Their magnitudes and colors are those of pre-main-sequence stars in the mass range 0.6-3 M(circle dot), mostly concentrated in the main cluster, but with secondary subclusters spread over a region across similar to 45 pc. These subclusters appear to be spatially coincident with previously known knots of molecular gas identified in ground-based and Infrared Space Observatory observations. We show that NGC 346 is a complex region, being shaped by its massive stars, and the observations presented here represent a key step toward the understanding of how star formation occurred and has progressed in this low-metallicity environment. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. ESA, Space Telescope Operat Div, F-75738 Paris 15, France. INAF, Osservatorio Astron Bologna, I-40127 Bologna, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. UCL, Dept Phys & Astron, London WC1E 6BT, England. New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. RP Nota, A (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. EM nota@stsci.edu RI Clampin, mark/D-2738-2012; OI Tosi, Monica/0000-0002-0986-4759 NR 17 TC 49 Z9 49 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 MAR 20 PY 2006 VL 640 IS 1 BP L29 EP L33 DI 10.1086/503301 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RG UT WOS:000236143300008 ER PT J AU Opher, M Stone, EC Liewer, PC AF Opher, M Stone, EC Liewer, PC TI The effects of a local interstellar magnetic field on Voyager 1 and 2 observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE interplanetary medium; ISM : kinematics and dynamics; solar wind; Sun : magnetic fields ID 3D MHD SIMULATIONS; TERMINATION SHOCK; SOLAR-SYSTEM; HELIOSPHERE; HELIOSHEATH; HELIOPAUSE; DIRECTION; EDGE; JET AB We show that an interstellar magnetic field can produce a north-south asymmetry in the solar wind termination shock. Using Voyager 1 and 2 measurements, we suggest that the angle alpha between the interstellar wind velocity and the magnetic field is 30 degrees < alpha < 60 degrees. The distortion of the shock is such that termination shock particles could have streamed outward along the spiral interplanetary magnetic field connecting Voyager 1 to the shock when the spacecraft was within similar to 2 AU of the shock. The shock distortion is larger in the southern hemisphere, and Voyager 2 could be connected to the shock when it is within similar to 5 AU of the shock, but with particles from the shock streaming inward along the field. Tighter constraints on the interstellar magnetic field should be possible when Voyager 2 crosses the shock in the next several years. C1 George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. CALTECH, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Opher, M (reprint author), George Mason Univ, Dept Phys & Astron, 4400 Univ Dr, Fairfax, VA 22030 USA. EM mopher@physics.gmu.edu; ecs@srl.caltech.edu; paulett.liewer@jpl.nasa.gov NR 22 TC 120 Z9 121 U1 0 U2 8 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 MAR 20 PY 2006 VL 640 IS 1 BP L71 EP L74 DI 10.1086/503251 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RG UT WOS:000236143300018 ER PT J AU Righter, K Leeman, WP Hervig, RL AF Righter, K Leeman, WP Hervig, RL TI Partitioning of Ni, Co and V between spinel-structured oxides and silicate melts: Importance of spinel composition SO CHEMICAL GEOLOGY LA English DT Article DE trace element partitioning; spinel; fractional crystallization; chromite; magnetite ID SCIENTIFIC DRILLING PROJECT; MAFIC IGNEOUS SYSTEMS; ION MICRO-PROBE; ATMOSPHERIC-PRESSURE; THERMODYNAMIC DATA; HIGH-TEMPERATURES; OXYGEN FUGACITY; REDOX REACTIONS; TRACE-ELEMENT; GEOCHEMICAL STRATIGRAPHY AB Partitioning of Ni, Co and V between Cr-rich spinels and basaltic melt has been studied experimentally between 1150 and 1325 degrees C, and at controlled oxygen fugacity from the Co-CoO buffer to slightly above the hematite-magnetite buffer. These new results, together with new Ni, Co and V analyses of experimental run products from Leeman [Leeman, W.P., 1974. Experimental determination of the partitioning of divalent cations between olivine and basaltic liquid, Pt. II. PhD thesis, Univ. Oregon, 231-337.], show that experimentally determined spinel-melt partition coefficients (D) are dependent upon temperature (T), oxygen fugacity (fO(2)) and spinel composition. In particular, partition coefficients determined on doped systems are higher than those in natural (undoped) systems, perhaps due to changing activity coefficients over the composition range defined by the experimental data. Using our new results and published runs (n = 85), we obtain a multilinear regression equation that predicts experimental D(V) values as a function of T,fO(2), concentration of V in melt and spinel composition. This equation allows prediction of D(V) spinel/melt values for natural mafic liquids at relevant crystallization conditions. Similarly, D(Ni) and D(Co) values can be inferred from our experiments at redox conditions approaching the QFM buffer, temperatures of 1150 to 1250 T and spinel composition (early Cr-bearing and later Ti-magnetite) appropriate for basic magma differentiation. When coupled with major element modelling of liquid lines of descent, these values (D(Ni) sp/melt=10 and D(Co) sp/melt=5) closely reproduce the compositional variation observed in komatiite, mid-ocean ridge basalt (MORB), ocean island basalt (OIB) and basalt to rhyolite suites. Published by Elsevier B.V. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Rice Univ, Dept Earth Sci, Houston, TX 77251 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. RP Righter, K (reprint author), NASA, Lyndon B Johnson Space Ctr, Mailcode KT,2101 NASA Pkwy, Houston, TX 77058 USA. EM kevin.righter-1@nasa.gov NR 54 TC 42 Z9 44 U1 3 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD MAR 20 PY 2006 VL 227 IS 1-2 BP 1 EP 25 DI 10.1016/j.chemgeo.2005.05.011 PG 25 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 027HV UT WOS:000236406900001 ER PT J AU Penn, SD Ageev, A Busby, D Harry, GM Gretarsson, AM Numata, K Willems, P AF Penn, SD Ageev, A Busby, D Harry, GM Gretarsson, AM Numata, K Willems, P TI Frequency and surface dependence of the mechanical loss in fused silica SO PHYSICS LETTERS A LA English DT Article ID THERMAL NOISE; LIGO; COATINGS AB We have compiled measurements of the mechanical loss in fused silica from samples spanning a wide range of geometries and resonant frequency in order to model the known variation of the loss with frequency and surface-to-volume ratio. This improved understanding of the mechanical loss has contributed significantly to the design of advanced interferometric gravitational wave detectors, which require ultra-low loss materials for their test mass mirrors. (c) 2005 Elsevier B.V. All rights reserved. C1 Hobart & William Smith Coll, Dept Phys, Geneva, NY 14456 USA. Syracuse Univ, Dept Phys, Syracuse, NY 13244 USA. CALTECH, LIGO Lab, Pasadena, CA 91125 USA. MIT, LIGO Lab, Cambridge, MA 02139 USA. Embry Riddle Aeronaut Univ, Dept Phys, Prescott, AZ 86301 USA. NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. RP Penn, SD (reprint author), Hobart & William Smith Coll, Dept Phys, Geneva, NY 14456 USA. EM penn@hws.edu NR 22 TC 62 Z9 63 U1 3 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 20 PY 2006 VL 352 IS 1-2 BP 3 EP 6 DI 10.1016/j.physleta.2005.11.046 PG 4 WC Physics, Multidisciplinary SC Physics GA 019TM UT WOS:000235859600002 ER PT J AU Lehnert, H Stone, R Heimler, W AF Lehnert, H Stone, R Heimler, W TI New species of Poecilosclerida (Demospongiae, Porifera) from the Aleutian Islands, Alaska, USA SO ZOOTAXA LA English DT Article DE taxonomy; Porifera; Demospongiae; Poecilosclerida; new species; N-Pacific; Aleutian Islands; Alaska AB Five new species of poecilosclerid sponges, Artemisina amlia sp. nov., Coelosphaera oglalai sp. nov., Melonanchora globogilva sp. nov., Tedania kagalaskai sp. nov., and Mycale carlilei sp. nov, are described from the Aleutian Islands, Alaska, from depths ranging between 100-190m and are compared with congeners of the North Pacific Ocean. C1 Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. Univ Erlangen Nurnberg, Inst Zool 1, D-91054 Erlangen, Germany. RP Lehnert, H (reprint author), Eichenstr 14, D-86507 Oberottmarshausen, Germany. EM Helm.Lehnert@t-online.de NR 42 TC 0 Z9 0 U1 1 U2 1 PU MAGNOLIA PRESS PI AUCKLAND PA PO BOX 41383, AUCKLAND, ST LUKES 1030, NEW ZEALAND SN 1175-5326 EI 1175-5334 J9 ZOOTAXA JI Zootaxa PD MAR 20 PY 2006 IS 1155 BP 1 EP 23 PG 23 WC Zoology SC Zoology GA 022NZ UT WOS:000236063900001 ER PT J AU Chi, EC Mende, SB Fok, MC Reeves, GD AF Chi, EC Mende, SB Fok, MC Reeves, GD TI Proton auroral intensifications and injections at synchronous altitude SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODEL; SUBSTORMS; MAGNETOSPHERE; FIELD AB In sudden flux increases at synchronous altitude the lower energy channels often show progressively more delay or dispersion. It is usually assumed that the dispersion is caused by a simultaneous injection of particles of all energies at some location, and by the subsequent drift of these particles to the synchronous altitude measurement site "downstream'' of the injection event. In this paper we present a method for timing and locating the injections from proton auroral precipitation inferred by the Lyman a emission data from the IMAGE FUV instrument. We compare the timing of the proton flux increases observed by the Los Alamos National Laboratory synchronous altitude satellites to the time delay predicted by a model describing the longitudinal drift of particles in the magnetosphere. We present comparisons for eleven substorm particle injections and find that the observed azimuthal drift times are reasonably consistent with those calculated by a simple model using the Tsyganenko 89 magnetic and Volland electric field models as input. This consistency supports the concept that the proton auroral intensification at substorm onset and the proton injection in the magnetosphere occur at the same magnetic local time (longitude). C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chi, EC (reprint author), Univ Calif Berkeley, Space Sci Lab, Centennial Dr & Grizzly Pk Blvd, Berkeley, CA 94720 USA. EM mende@ssl.berkeley.edu RI Fok, Mei-Ching/D-1626-2012; Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 19 TC 3 Z9 3 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 MAR 18 PY 2006 VL 33 IS 6 AR L06104 DI 10.1029/2005GL024656 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026HY UT WOS:000236331200003 ER PT J AU Chen, SH Moore, TE AF Chen, SH Moore, TE TI Magnetospheric convection and thermal ions in the dayside outer magnetosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SUBAURORAL POLARIZATION STREAM; EXTREME-ULTRAVIOLET IMAGER; IN-SITU OBSERVATIONS; ELECTRIC-FIELD; RING CURRENT; ART.; PLASMASPHERE; DYNAMICS; PLASMAPAUSE; DENSITY AB We have surveyed 3.5 years of Polar Thermal Ion Dynamics Experiment (TIDE) data between 1 January 2000 and 30 June 2003, when Polar apogee paths ( sections of orbits with geocentric distances r>5 R-E) were in the dayside outer magnetosphere, to study the spatial distribution of thermal ions and the magnetospheric convection paths of the thermal ions, as a function of interplanetary magnetic field (IMF) orientation. We have found a dawn-dusk asymmetry in the occurrence of detectable thermal ions above the instrument threshold. The occurrence rate was significantly higher at the duskside. The probability of observing thermal ions, particularly at 1300-1600 local time (LT) near the magnetopause, was >50%, compared with <30% at the dawnside. We interpret the thermal ion events as the result of plasmaspheric drainage plumes, as observed by IMAGE spacecraft or geosynchronous orbiters. The episodic appearance of the thermal ions in the outer magnetosphere could be a significant factor for the dynamo process of global magnetospheric convection. The variation of the convection pattern due to the IMF orientation is consistent with equatorward and poleward reconnection scenarios that superimpose dayside convection driven by reconnection on top of the background convection driven by a viscous interaction at the magnetopause, together with the corotation of the magnetospheric plasma with the ionosphere. C1 NASA, Goddard Space Flight Ctr, Heliospher Phys Branch, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD USA. RP NASA, Goddard Space Flight Ctr, Heliospher Phys Branch, Code 612-2, Greenbelt, MD 20771 USA. EM sheng-hsien.chen@gsfc.nasa.gov RI Moore, Thomas/D-4675-2012 OI Moore, Thomas/0000-0002-3150-1137 NR 34 TC 28 Z9 28 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 18 PY 2006 VL 111 IS A3 AR A03215 DI 10.1029/2005JA011084 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026JJ UT WOS:000236334900001 ER PT J AU Grodent, D Gerard, JC Gustin, J Mauk, BH Connerney, JEP Clarke, JT AF Grodent, D Gerard, JC Gustin, J Mauk, BH Connerney, JEP Clarke, JT TI Europa's FUV auroral tail on Jupiter SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID IO FLUX TUBE; PLASMA TORUS; ENVIRONMENT; EMISSIONS; SIGNATURE; WAKE AB Ultraviolet images of Jupiter's northern aurora obtained in 2005 confirm the existence of an electromagnetic interaction between Europa and the Jovian ionosphere. The auroral signature shows a two-component structure: a quasi-circular Europa spot, followed by a previously undetected faint tail emission trailing in the direction of corotation flow. The characteristic brightness for the auroral spot is similar to 14 +/- 1 kR above background, and approximately 7 +/- 1 kR for the tail. The spot's size is similar to 1100 km, magnetically mapping to an interaction region <= 15 Europa diameters. The auroral tail extends over similar to 5000 km, which maps along a region of at least 70 Europa diameters. The ultraviolet power emitted by both components varies from a fraction to several GW. The present study suggests auroral interaction at Europa similar to that at Io, but scaled-down by an order of magnitude, including a sub-corotating plasma plume in the geometrical wake of Europa. C1 Univ Liege, LPAP, B-4000 Liege, Belgium. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. RP Univ Liege, LPAP, Allee 6 Aout,17 B5c, B-4000 Liege, Belgium. EM d.grodent@ulg.ac.be RI Clarke, John/C-8644-2013; connerney, john/I-5127-2013; Mauk, Barry/E-8420-2017; OI Mauk, Barry/0000-0001-9789-3797; connerney, jack/0000-0001-7478-6462; GERARD, Jean-Claude/0000-0002-8565-8746 NR 25 TC 15 Z9 15 U1 0 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 MAR 17 PY 2006 VL 33 IS 6 AR L06201 DI 10.1029/2005GL025487 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026HW UT WOS:000236331000008 ER PT J AU Pulkkinen, A Klimas, A Vassiliadis, D Uritsky, V Tanskanen, E AF Pulkkinen, A Klimas, A Vassiliadis, D Uritsky, V Tanskanen, E TI Spatiotemporal scaling properties of the ground geomagnetic field variations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELEMENTARY CURRENT SYSTEMS; DYNAMIC MAGNETOSPHERE; AVALANCHING SYSTEM; AE-INDEX; ART.; INDUCTION; TIME; FLUCTUATIONS; ELECTROJET; CURRENTS AB [1] The spatiotemporal scaling properties of the auroral region ground horizontal magnetic field fluctuations are investigated in terms of structure function analysis. First, the distorting effects of the continuation of the magnetic field from the ionosphere to the ground level and the effects of the geomagnetic induction on the derived scalings are studied. It is found that the spatial fluctuations of the magnetic field and its time derivative are distorted by the field continuation in the ranges of scales of the data, i.e., 100 < Delta r < 2400 km (above similar to 1000 km, analysis is spatially one-dimensional) and 10 < tau < 10(4) s. Specifically, the extent of the distortion is found to be dependent on the original ionospheric level scaling of the fluctuations. The effect of the geomagnetic induction is found to be negligible in the ranges of scales of the data. The main findings of the study are (1) there is a significant change in the dynamics of the field fluctuations in the range 80 < tau < 100 s where the time derivative of the magnetic field undergoes a transition from correlated to uncorrelated temporal behavior, (2) the spatiotemporal behavior of the time derivative of the magnetic field above temporal scales of 100 s resembles that of uncorrelated white noise, (3) the spatial symmetry of the field fluctuations increases during substorms, indicating the presence of spatially less ordered ionospheric equivalent currents, and (4) the spatial scaling properties of the field fluctuations may explain why the magnetotelluric sounding method works better than expected in auroral regions. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. St Petersburg State Univ, Dept Phys, St Petersburg 199034, Russia. St Petersburg State Univ, Inst Phys, St Petersburg 199034, Russia. Finnish Meteorol Inst, Space Res Unit, FIN-00101 Helsinki, Finland. RP Pulkkinen, A (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM antti.pulkkinen@gsfc.nasa.gov NR 42 TC 25 Z9 25 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 MAR 17 PY 2006 VL 111 IS A3 AR A03305 DI 10.1029/2005JA011294 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026JI UT WOS:000236334800002 ER PT J AU Lundgren, P Lu, Z AF Lundgren, P Lu, Z TI Inflation model of Uzon caldera, Kamchatka, constrained by satellite radar interferometry observations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CAMPI FLEGREI CALDERA; VOLCANO; UNREST AB We analyzed RADARSAT-1 synthetic aperture radar (SAR) data to compute interferometric SAR (InSAR) images of surface deformation at Uzon caldera, Kamchatka, Russia. From 2000 to 2003 approximately 0.15 m of inflation occurred at Uzon caldera, extending beneath adjacent Kikhpinych volcano. This contrasts with InSAR data showing no significant deformation during either the 1999 to 2000, or 2003 to 2004, time periods. We performed three sets of numerical source inversions to fit InSAR data from three different swaths spanning 2000 to 2003. The preferred source model is an irregularly shaped, pressurized crack, dipping similar to 20 degrees to the NW, 4 km below the surface. The geometry of this solution is similar to the upper boundary of the geologically inferred magma chamber. Extension of the surface deformation and source to adjacent Kikhpinych volcano, without an eruption, suggests that the deformation is more likely of hydrothermal origin, possibly driven by recharge of the magma chamber. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. US Geol Ctr EROS, Sci Applicat Int Corp, Sioux Falls, SD 57198 USA. RP Lundgren, P (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM paul@weed.jpl.nasa.gov NR 19 TC 18 Z9 18 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 MAR 16 PY 2006 VL 33 IS 6 AR L06301 DI 10.1029/2005GL025181 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 026HU UT WOS:000236330800006 ER PT J AU Sud, YC Mocko, DM Lin, SJ AF Sud, YC Mocko, DM Lin, SJ TI Performance of two cloud-radiation parameterization schemes in the finite volume general circulation model for anomalously wet May and June 2003 over the continental United States and Amazonia SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID COMMUNITY CLIMATE MODEL; RELAXED ARAKAWA-SCHUBERT; NUMERICAL WEATHER PREDICTION; MOIST-CONVECTION; SKILL SCORES; PART II; MICROPHYSICS; VERIFICATION; SIMULATION; GCM AB [1] An objective assessment of the impact of a new cloud scheme, called Microphysics of Clouds with Relaxed Arakawa-Schubert Scheme (McRAS) ( together with its radiation modules), on the finite volume general circulation model (fvGCM) was made with a set of ensemble forecasts that invoke performance evaluation over both weather and climate timescales. The performance of McRAS ( and its radiation modules) was compared with that of the National Center for Atmospheric Research Community Climate Model (NCAR CCM3) cloud scheme ( with its NCAR physics radiation). We specifically chose the boreal summer months of May and June 2003, which were characterized by an anomalously wet eastern half of the continental United States as well as northern regions of Amazonia. The evaluation employed an ensemble of 70 daily 10-day forecasts covering the 61 days of the study period. Each forecast was started from the analyzed initial state of the atmosphere and spun-up soil moisture from the first-day forecasts with the model. Monthly statistics of these forecasts with up to 10-day lead time provided a robust estimate of the behavior of the simulated monthly rainfall anomalies. Patterns of simulated versus observed rainfall, 500-hPa heights, and top-of-the-atmosphere net radiation were recast into regional anomaly correlations. The correlations were compared among the simulations with each of the schemes. The results show that fvGCM with McRAS and its radiation package performed discernibly better than the original fvGCM with CCM3 cloud physics plus its radiation package. The McRAS cloud scheme also showed a reasonably positive response to the observed sea surface temperature on mean monthly rainfall fields at different time leads. This analysis represents a method for helpful systematic evaluation prior to selection of a new scheme in a global model. C1 NASA, Climate & Radiat Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, Beltsville, MD USA. Princeton Univ, Geophys Fluid Dynam Lab, Princeton, NJ 08540 USA. RP Sud, YC (reprint author), NASA, Climate & Radiat Branch, Goddard Space Flight Ctr, Code 613-2,Bldg 33, Greenbelt, MD 20771 USA. EM sud@climate.gsfc.nasa.gov NR 44 TC 4 Z9 4 U1 0 U2 1 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 MAR 16 PY 2006 VL 111 IS D6 AR D06201 DI 10.1029/2005JD006246 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 026IG UT WOS:000236332000003 ER PT J AU Tobin, DC Revercomb, HE Knuteson, RO Lesht, BM Strow, LL Hannon, SE Feltz, WF Moy, LA Fetzer, EJ Cress, TS AF Tobin, DC Revercomb, HE Knuteson, RO Lesht, BM Strow, LL Hannon, SE Feltz, WF Moy, LA Fetzer, EJ Cress, TS TI Atmospheric Radiation Measurement site atmospheric state best estimates for Atmospheric Infrared Sounder temperature and water vapor retrieval validation SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WEATHER PREDICTION; SEA-SURFACE; AIRS/AMSU/HSB; EMISSIVITY; SATELLITES; RADIANCES; PROFILES; MOISTURE; PROGRAM; DESIGN AB The Atmospheric Infrared Sounder ( AIRS) is the first of a new generation of advanced satellite-based atmospheric sounders with the capability of obtaining high-vertical resolution profiles of temperature and water vapor. The high-accuracy retrieval goals of AIRS (e.g., 1 K RMS in 1 km layers below 100 mbar for air temperature, 10% RMS in 2 km layers below 100 mbar for water vapor concentration), combined with the large temporal and spatial variability of the atmosphere and difficulties in making accurate measurements of the atmospheric state, necessitate careful and detailed validation using well-characterized ground-based sites. As part of ongoing AIRS Science Team efforts and a collaborative effort between the NASA Earth Observing System (EOS) project and the Department of Energy Atmospheric Radiation Measurement (ARM) program, data from various ARM and other observations are used to create best estimates of the atmospheric state at the Aqua overpass times. The resulting validation data set is an ensemble of temperature and water vapor profiles created from radiosondes launched at the approximate Aqua overpass times, interpolated to the exact overpass time using time continuous ground-based profiles, adjusted to account for spatial gradients within the Advanced Microwave Sounding Unit (AMSU) footprints, and supplemented with limited cloud observations. Estimates of the spectral surface infrared emissivity and local skin temperatures are also constructed. Relying on the developed ARM infrastructure and previous and ongoing characterization studies of the ARM measurements, the data set provides a good combination of statistics and accuracy which is essential for assessment of the advanced sounder products. Combined with the collocated AIRS observations, the products are being used to study observed minus calculated AIRS spectra, aimed at evaluation of the AIRS forward radiative transfer model, AIRS observed radiances, and temperature and water vapor profile retrievals. This paper provides an introduction to the ARM site best estimate validation products and characterizes the accuracy of the AIRS team version 4 atmospheric temperature and water vapor retrievals using the ARM products. The AIRS retrievals over tropical ocean are found to have very good accuracy for both temperature and water vapor, with RMS errors approaching the theoretical expectation for clear sky conditions, while retrievals over a midlatitude land site have poorer performance. The results demonstrate the importance of using specialized "truth'' sites for accurate assessment of the advanced sounder performance and motivate the continued refinement of the AIRS science team retrieval algorithm, particularly for retrievals over land. C1 Univ Wisconsin, Ctr Space Sci & Engn, Cooperat Inst Meteorol Satellite, Madison, WI 53706 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Tobin, DC (reprint author), Univ Wisconsin, Ctr Space Sci & Engn, Cooperat Inst Meteorol Satellite, 1225 W Dayton St, Madison, WI 53706 USA. EM dave.tobin@ssec.wisc.edu OI Lesht, Barry/0000-0003-0801-4290 NR 35 TC 161 Z9 161 U1 1 U2 9 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 MAR 16 PY 2006 VL 111 IS D9 AR D09S14 DI 10.1029/2005JD006103 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 026IL UT WOS:000236332500001 ER PT J AU Kletetschka, G Fuller, MD Kohout, T Wasilewski, PJ Herrero-Bervera, E Ness, NF Acuna, MH AF Kletetschka, G Fuller, MD Kohout, T Wasilewski, PJ Herrero-Bervera, E Ness, NF Acuna, MH TI TRM in low magnetic fields: a minimum field that can be recorded by large multidomain grains SO PHYSICS OF THE EARTH AND PLANETARY INTERIORS LA English DT Article; Proceedings Paper CT 1st European-Geoscience-Union General Assembly on Developments in Techniques and Methods Related to Rock Magnetism CY APR 25-30, 2004 CL Nice, FRANCE DE TRM; paleointensity; meteorites; multidomain magnetic minerals; empirical law; mars; magnetism ID ILMENITE SOLID-SOLUTION; THERMOREMANENT MAGNETIZATION; REMANENT MAGNETIZATION; STILLWATER COMPLEX; IGNEOUS ROCKS; HEMATITE; SERIES; SIZE AB Thermally acquired remanent magnetization is important for the estimation of the past magnetic field present at the time of cooling. Rocks that cool slowly commonly contain magnetic grains of millimeter scale. This study investigated 1-mm-sized magnetic minerals of iron, iron-nickel, magnetite, and hematite and concluded that the thermoremanent magnetization (TRM) acquired by these grains did not accurately record the ambient magnetic fields less than 1 mu T. Instead, the TRM of these grains fluctuated around a constant value. Consequently, the magnetic grain ability to record the ambient field accurately is reduced. Above the critical field, TRM acquisition is governed by an empirical law and is proportional to saturation magnetization (M-s). The efficiency of TRM is inversely proportional to the mineral's saturation magnetization M-s and is related to the number of domains in the magnetic grains. The absolute field for which we have an onset of TRM sensitivity is inversely proportional to the size of the magnetic grain. These results have implications for previous reports of random directions in meteorites during alternating field demagnetization, or thermal demagnetization of TRM. Extraterrestrial magnetic fields in our solar system are weaker than the geomagnetic field by several orders of magnitude. Extraterrestrial rocks commonly contain large iron-based magnetic minerals as a common part of their composition, and therefore ignoring this behavior of multidomain grains can result in erroneous paleofield estimates. (c) 2006 Elsevier B.V. All rights reserved. C1 Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Acad Sci Czech Republ, Inst Geol, Prague, Czech Republic. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Hawaii Manoa, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. Charles Univ, Dept Appl Geosci, Prague, Czech Republic. Univ Helsinki, Div Geophys, Helsinki, Finland. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. RP Kletetschka, G (reprint author), Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. EM Gunther.Kletetschka@gsfc.nasa.gov RI Kletetschka, Gunther/C-9996-2011; Kohout, Tomas/C-1394-2008 OI Kletetschka, Gunther/0000-0002-0645-9037; Kohout, Tomas/0000-0003-4458-3650 NR 20 TC 21 Z9 21 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-9201 J9 PHYS EARTH PLANET IN JI Phys. Earth Planet. Inter. PD MAR 16 PY 2006 VL 154 IS 3-4 SI SI BP 290 EP 298 DI 10.1016/j.pepi.2005.07.005 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 026JZ UT WOS:000236336500009 ER PT J AU Tedesco, M Kim, EJ Cline, D Graf, T Koike, T Armstrong, R Brodzik, MJ Hardy, J AF Tedesco, M Kim, EJ Cline, D Graf, T Koike, T Armstrong, R Brodzik, MJ Hardy, J TI Comparison of local scale measured and modelled brightness temperatures and snow parameters from the CLPX 2003 by means of a dense medium radiative transfer theory model SO HYDROLOGICAL PROCESSES LA English DT Article; Proceedings Paper CT 62nd Eastern Snow Conference (ESC) CY JUN 07-10, 2005 CL Waterloo, CANADA DE snow; microwave remote sensing; DMRT; CLPX ID PAIR DISTRIBUTION-FUNCTIONS; ICE AB Some 27 years of passive microwave satellite observations have demonstrated the value of remote sensing for cryospheric applications, albeit at regional to hemispheric scales due to the relatively large sensor footprints (e.g. similar to 25 km x 25 km for the advanced microwave scanning radiometer). At the other extreme there is the primarily local-scale in situ experience of the snow community. Until higher-resolution sensors become available, understanding the effects of sub-pixel heterogeneity and the downscaling of observations remains an important topic. In order to provide a baseline for performing scaling studies and for future radiance-based hydrological assimilation schemes, an evaluation of snowpack forward radiance modelling at the plot scale (least heterogeneous scale) is carfied out. Snow microwave radiance models based on dense medium radiative transfer (DMRT) theory incorporate a high degree of physical fidelity, yet dense medium models are particularly sensitive to snowpack structural parameters such as grain size, density, and depth (parameters that may vary substantially within a snowpack). The DMRT performance is evaluated through the use of a fitting technique with respect to snow grain size, a hydrologically important parameter related to the total amount of melt water stored in a snowpack, snowpack metamorphism, vertical energy transport and melt dynamics, as well as various quantities useful in surface energy balance studies. All remaining snow input parameters to the model are derived from snow pit measurements. Model-predicted radiances are evaluated using microwave brightness measurements collected during the NASA Cold Land Process Experiment (CLPX) by the University of Tokyo's Ground-Based Microwave Radiometer-7 (GBMR-7) system at 18.7, 36.5, and 89 GHz, with incidence angles ranging from 30 to 70 degrees. The detailed CLPX microwave and snow data provide an excellent opportunity to gain insight into the strengths and weaknesses of this approach. Copyright (c) 2006 John Wiley & Sons, Ltd. C1 NASA, Goddard Space Flight Ctr, Dept Civil Engn, GEST, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Lab Hydrospher & Biospher Sci Proc, Greenbelt, MD USA. NOAA, Natl Weather Serv, Natl Operat Hydrol Remote Sensing Ctr, Chanhassen, MN USA. Univ Tokyo, Tokyo, Japan. Univ Colorado, Natl Snow & Ice Data Ctr, Boulder, CO USA. USACE, Cold Reg Res & Engn Lab, Hanover, NH USA. RP Tedesco, M (reprint author), NASA, Goddard Space Flight Ctr, Dept Civil Engn, GEST, Mailstop 614-6, Greenbelt, MD 20771 USA. EM mtedesco@umbc.edu RI Tedesco, Marco/F-7986-2015 NR 14 TC 19 Z9 19 U1 0 U2 8 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0885-6087 J9 HYDROL PROCESS JI Hydrol. Process. PD MAR 15 PY 2006 VL 20 IS 4 BP 657 EP 672 DI 10.1002/hyp.6129 PG 16 WC Water Resources SC Water Resources GA 026IK UT WOS:000236332400004 ER PT J AU Alston, WB Scheiman, DA Sivko, GS AF Alston, WB Scheiman, DA Sivko, GS TI A comparison study: The new extended shelf life isopropyl ester PMR technology versus the traditional methyl ester PMR approach SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE polyimide composites; high performance polymers; composite thermal oxidative properties; PMR II-50 and VCAP-75; solution and prepreg shelf life ID RESIN AB Polymerization of monomeric reactants (PMR) monomer solutions and carbon cloth prepregs of PMR II-50 and VCAP-75 were prepared using both the traditional limited shelf life methanol based PMR approach and a novel extended shelf life isopropanol based PMR approach. The methyl ester and isopropyl ester based PMR monomer solutions and PMR prepregs were aged for up to 4 years at freezer and room temperatures. The aging products formed were monitored using high pressure liquid chromatography (HPLC). The composite processing flow characteristics and volatile contents of the aged prepregs were correlated versus room temperature storage time. Composite processing cycles were developed and six-ply cloth laminates were fabricated with prepregs after various extended room temperature storage times. The composites were then evaluated for glass transition temperature (T-g), thermal decomposition temperature (T-d), initial flexural strength (FS), and modulus (FM), long term (1000 h at 316 degrees C) thermal oxidative stability (TOS), and retention of FS and FM after 1000 h aging at 316 degrees C. The results for each ester system were comparable. Freezer storage was found to prevent the formation of aging products for both ester systems. Room temperature storage of the novel isopropyl ester system increased PMR monomer solution and PMR prepreg shelf life by at least an order of magnitude, while maintaining composite thermal and mechanical properties. (c) 2006 Wiley Periodicals, Inc. C1 NASA, Glenn Res Ctr, VTD, USA Res Lab ARL, Cleveland, OH 44135 USA. NASA, Lewis Res Ctr, QSS Grp Inc, Cleveland, OH 44135 USA. NASA, Lewis Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. RP Alston, WB (reprint author), NASA, Glenn Res Ctr, VTD, USA Res Lab ARL, 2100 Brookpk Rd, Cleveland, OH 44135 USA. EM william.b.alston@grc.nasa.gov; daniel.a.scheiman@grc.nasa.gov NR 19 TC 0 Z9 0 U1 1 U2 3 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 MAR 15 PY 2006 VL 99 IS 6 BP 3549 EP 3564 DI 10.1002/app.22925 PG 16 WC Polymer Science SC Polymer Science GA 012MO UT WOS:000235343500088 ER PT J AU Chernov, AA Petrova, E Rashkovich, LN AF Chernov, AA Petrova, E Rashkovich, LN TI Dependence of the CaOx and MgOx growth rate on solution stoichiometry. Non-Kossel crystal growth SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE atomic force microscopy; biomaterials; growth models; interfaces; growth from solutions; calcium compounds ID CALCIUM-OXALATE MONOHYDRATE; KINETICS; DYNAMICS; STEP AB Rates of elementary growth step propagation on the CaOx and MgOx crystal faces were measured by AFM in flowing Solution maintaining kinetic growth mode. Dependence of the step rate on the stoichiometry ratio r = [cation]/[anion] in solution ill the range 5 x 10(-2)< r < 20 for CaOx and 0.2 < r < 5 for MgOx was found. The dependence is nearly symmetrical with respect to the replacement r by l/r or vice versa, i.e. v(r) congruent to v(l/r), with a clear maximum for stoichiometric solution, r = 1. It turns out that v = v(r(1/2) + r(-1/2)), in approximate agreement with the kink growth rate theory for binary and other non-Kossel crystals [J. Zhang, G.H. Nancollas, J. Colloid Interface Sci. 200 (1998) 131; A.A. Chernov, J. Mater. Sci. Mater. Electron. 12 (2001) 437], under the assumption that the cation and anion attachment frequencies are proportional to concentrations of these species only and that the proportionality coefficients, the frequency factor, is independent of the ion type. The fitting frequency factor is similar to 10(5) l/mol s, leading to a slightly exaggerated vibration frequency of species in activated state, 4 x 10(12) l/s, at activation energy 8 kcal/mol. Possible reasons for the observed deviations from the theoretical predictions are discussed. Kink rate calculation for a ternary system is presented in Appendix A. (c) 2005 Published by Elsevier B.V. C1 NASA, George C Marshall Space Flight Ctr, BAE Syst, Huntsville, AL 35812 USA. Moscow MV Lomonosov State Univ, Dept Phys, Moscow 119992, Russia. RP Chernov, AA (reprint author), NASA, George C Marshall Space Flight Ctr, BAE Syst, Huntsville, AL 35812 USA. EM alex.chernov@msfc.nasa.gov NR 23 TC 33 Z9 36 U1 0 U2 7 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 MAR 15 PY 2006 VL 289 IS 1 BP 245 EP 254 DI 10.1016/j.jcrysgro.2005.10.109 PG 10 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 023YV UT WOS:000236163000043 ER PT J AU Bloemhof, EE AF Bloemhof, EE TI Design of a 'self-nulling' beam combiner needing no external phase inversion SO OPTICS COMMUNICATIONS LA English DT Article ID EXTRASOLAR PLANETS; INTERFEROMETRY AB The complex optics of planned space-based nulling interferometers intended to search for exosolar planets will be simplified substantially if the modified Mach-Zehnder beam combiner is used in a novel fashion, extracting the null from ports traditionally used as bright outputs. This approach entirely eliminates the need for special phase-flipping optics, exploiting instead the broad-band phase shifts intrinsic to the beam splitters themselves. The theory of this 'self-nulling' approach is presented, and specifications are given for its use with and without adaptive nulling. (C) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91101 USA. RP Bloemhof, EE (reprint author), CALTECH, Jet Propuls Lab, 4800 Oak Grove Dr,MS 171-243, Pasadena, CA 91101 USA. EM Eric.E.Bloemhof@jpl.nasa.gov NR 18 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAR 15 PY 2006 VL 259 IS 2 BP 395 EP 399 DI 10.1016/j.optcom.2005.09.003 PG 5 WC Optics SC Optics GA 016TK UT WOS:000235643100001 ER PT J AU Ramirez-Serrano, J Yu, N Kohel, JM Kellogg, JR Maleki, L AF Ramirez-Serrano, J Yu, N Kohel, JM Kellogg, JR Maleki, L TI Multistage two-dimensional magneto-optical trap as a compact cold atom beam source SO OPTICS LETTERS LA English DT Article ID SLOW AB A compact cold atom beam source based on a multistage two-dimensional magneto-optical trap (MOT) has been demonstrated and characterized. The multiple-stage design greatly reduces the overall size of the source apparatus while providing a high flux of atoms. The cold atom beam was used to load a separate MOT in ultrahigh vacuum, and we obtained an actual trap loading rate of 1.5 x 10(9) atoms/s while using only 20 mW of total laser power for the source. The entire source apparatus, including optics, can fit into a 4 cm x 4 cm x 13 cm volume. (c) 2006 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yu, N (reprint author), Sandia Natl Labs, MS 9055, Livermore, CA 94551 USA. EM nan.yu@jpl.nasa.gov NR 8 TC 6 Z9 6 U1 1 U2 6 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 MAR 15 PY 2006 VL 31 IS 6 BP 682 EP 684 DI 10.1364/OL.31.000682 PG 3 WC Optics SC Optics GA 019KG UT WOS:000235833400002 PM 16544589 ER PT J AU Zhong, ZM AF Zhong, ZM TI Stoichiometric lanthanum chromite based ceramic interconnects with low sintering temperature SO SOLID STATE IONICS LA English DT Article DE SOFC; ceramic interconnect; low temperature sintering; co-sintering; LaCrO3 ID OXIDE FUEL-CELLS; THERMAL-EXPANSION; COMBUSTION SYNTHESIS; COMPATIBILITY; SEPARATORS AB Ceramic interconnects for use in solid oxide fuel cells are expected to operate between 800 similar to 1000 degrees C, sinter between 1400-1500 degrees C to allow co-firing and meet a number thermal mechanical requirements. The perovskite type (ABO(3)) lanthanum chromite based materials have emerged as a leading candidate that will meet these criteria by varying the composition on the A and B sites. A need therefore exists to determine this materials temperature dependent electrical and mechanical properties with respect to these site substitutions. In this investigation, oxide powders were prepared by the glycine-nitrate process. Ionic substitutions were carried out on A sites with calcium or strontium, and B sites with cobalt and aluminum, respectively. Only stoichiometric compositions were considered for the sake of stability. The powders and their sinterability were investigated by XRD, SEM, dilatometry and density measurements. The sintered materials were further examined by SEM, thermal expansion and electric conductivity measurements in order to elucidate the resulting microstructure, electrical and mechanical properties. (c) 2006 Elsevier B.V. All rights reserved. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM zhong11135@yahoo.com NR 20 TC 20 Z9 21 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD MAR 15 PY 2006 VL 177 IS 7-8 BP 757 EP 764 DI 10.1016/j.ssi.2006.01.023 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 033ZB UT WOS:000236892400020 ER PT J AU Paavola, CD Chan, SL Li, Y Mazzarella, KM McMillan, RA Trent, JD AF Paavola, CD Chan, SL Li, Y Mazzarella, KM McMillan, RA Trent, JD TI A versatile platform for nanotechnology based on circular permutation of a chaperonin protein SO NANOTECHNOLOGY LA English DT Article ID ASPARTATE TRANSCARBAMOYLASE; 5-AMINOLEVULINATE SYNTHASE; HYPERTHERMOPHILIC ARCHAEON; MOLECULAR LITHOGRAPHY; POLYPEPTIDE-CHAINS; BLOCK-COPOLYMERS; CATALYTIC CHAINS; STABILITY; DNA; NANOPARTICLES AB A number of protein complexes have been developed as nanoscale templates. These can be functionalized using peptide sequences that bind inorganic materials or by fusion to binding or catalytic proteins. In order to integrate peptides and proteins into specific positions in a protein template, we used circular permutation to relocate the amino and carboxy termini of the polypeptide chain. Additional sequences can then be joined to the protein termini. This minimizes disruption of the protein structure and reduces restrictions on size and conformation of the added sequence. We relocated the termini of a Sulfolobus shibatae chaperonin subunit to five different locations across the outside surface of the chaperonin complex (after residues 153, 267, 316, 480 and 499). These changes place the termini on the outside surface of the chaperonin complex. The permutants formed double rings and higher-order assemblies similar to those observed in the natural protein. When enhanced yellow fluorescent protein was fused to two chaperonin subunits permuted at positions 267 and 480, the resulting fusion protein was fluorescent and formed assembled double rings and higher-order structure. This approach is applicable to other nanoscale protein templates. C1 NASA, Ames Res Ctr, Bioenng Branch, Moffett Field, CA 94035 USA. SETI Inst, Mountain View, CA 94043 USA. RP Paavola, CD (reprint author), NASA, Ames Res Ctr, Bioenng Branch, Mail Stop 239-15, Moffett Field, CA 94035 USA. EM Chad.Paavola@nasa.gov NR 41 TC 28 Z9 28 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0957-4484 J9 NANOTECHNOLOGY JI Nanotechnology PD MAR 14 PY 2006 VL 17 IS 5 BP 1171 EP 1176 DI 10.1088/0957-4484/17/5/001 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 028OB UT WOS:000236496400009 ER PT J AU Samanta, MP Tongprasit, W Sethi, H Chin, CS Stolc, V AF Samanta, MP Tongprasit, W Sethi, H Chin, CS Stolc, V TI Global identification of noncoding RNAs in Saccharomyces cerevisiae by modulating an essential RNA processing pathway SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE HRA1; microarray; RNase P; yeast ID GENOME TILING ARRAYS; RIBOSOMAL-RNA; DROSOPHILA-MELANOGASTER; TRANSCRIBED SEQUENCES; GENE-EXPRESSION; PROTEIN; SUBUNIT; MRP; IDENTIFY; ELEMENTS AB Noncoding RNAs (ncRNAs) perform essential cellular tasks and play key regulatory roles in all organisms. Although several new ncRNAs in yeast were recently discovered by individual studies, to our knowledge no comprehensive empirical search has been conducted. We demonstrate a powerful and versatile method for global identification of previously undescribed ncRNAs by modulating an essential RNA processing pathway through the depletion of a key ribonucleoprotein enzyme component, and monitoring differential transcriptional activities with genome tiling arrays during the time course of the ribonucleoprotein depletion. The entire Saccharomyces cerevisiae genome was scanned during cell growth decay regulated by promoter-mediated depletion of Rpp1, an essential and functionally conserved protein component of the RNase P enzyme. In addition to most verified genes and ncRNAs, expression was detected in 98 antisense and intergenic regions, 74 that were further confirmed to contain previously undescribed RNAs. A class of ncRNAs, located antisense to coding regions of verified protein-coding genes, is discussed in this article. One member, HRA1, is likely involved in 18S rRNA maturation. C1 NASA, Ames Res Ctr, Genome Res Facil, Moffett Field, CA 94035 USA. Univ Calif San Francisco, Dept Biochem & Biophys, San Francisco, CA 94143 USA. Eloret Corp, Sunnyvale, CA 94086 USA. Systemix Inst, Cupertino, CA 95014 USA. RP Stolc, V (reprint author), NASA, Ames Res Ctr, Genome Res Facil, Moffett Field, CA 94035 USA. EM vstolc@mail.arc.nasa.gov NR 30 TC 58 Z9 59 U1 0 U2 3 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 MAR 14 PY 2006 VL 103 IS 11 BP 4192 EP 4197 DI 10.1073/pnas.0507669103 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 027QE UT WOS:000236429300048 PM 16537507 ER PT J AU Hartle, RE Killen, R AF Hartle, RE Killen, R TI Measuring pickup ions to characterize the surfaces and exospheres of planetary bodies: Applications to the Moon SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOLAR-WIND AB [1] The composition and structure of neutral exospheres imbedded in the solar wind can be determined by measurements of their pickup ion progeny. Using Earth's Moon as the parent body, we consider transport of pickup ions from their birthplaces to measurement sites on possible spacecraft orbits. An ion observed to have a specific mass and velocity at a spacecraft position can be mapped back to its point of birth on the surface or in the atmosphere. Ion measurements of this type are shown to be a sensitive way to map the composition of surfaces and atmospheres of bodies with surface bound exospheres. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Hartle, RE (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 910, Greenbelt, MD 20771 USA. EM rhartle@mite.gsfc.nasa.gov RI Killen, Rosemary/E-7127-2012; OI Steinberg, John/0000-0003-2491-1661; Coates, Andrew/0000-0002-6185-3125 NR 11 TC 34 Z9 34 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 MAR 11 PY 2006 VL 33 IS 5 AR L05201 DI 10.1029/2005GL024520 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 025MG UT WOS:000236269800003 ER PT J AU Su, H Read, WG Jiang, JH Waters, JW Wu, DL Fetzer, EJ AF Su, H Read, WG Jiang, JH Waters, JW Wu, DL Fetzer, EJ TI Enhanced positive water vapor feedback associated with tropical deep convection: New evidence from Aura MLS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SEA-SURFACE TEMPERATURE; RELATIVE-HUMIDITY; GREENHOUSE; CLOUD; ATMOSPHERE; OCEANS; THERMOSTAT; BUDGET AB [1] Recent simultaneous observations of upper tropospheric (UT) water vapor and cloud ice from the Microwave Limb Sounder (MLS) on the Aura satellite provide new evidence for tropical convective influence on UT water vapor and its associated greenhouse effect. The observations show that UT water vapor increases as cloud ice water content increases. They also show that, when sea surface temperature (SST) exceeds similar to 300 K, UT cloud ice associated with tropical deep convection increases sharply with increasing SST. The moistening of the upper troposphere by deep convection leads to an enhanced positive water vapor feedback, about 3 times that implied solely by thermodynamics. Over tropical oceans when SST greater than similar to 300 K, the 'convective UT water vapor feedback' inferred from the MLS observations contributes approximately 65% of the sensitivity of the clear-sky greenhouse parameter to SST. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Skillstorm Jet Prop Lab, Pasadena, CA 91125 USA. RP Su, H (reprint author), CALTECH, Jet Prop Lab, M-S 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Hui.Su@jpl.nasa.gov RI Wu, Dong/D-5375-2012 NR 29 TC 52 Z9 52 U1 0 U2 7 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 MAR 11 PY 2006 VL 33 IS 5 AR L05709 DI 10.1029/2005GL025505 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 025MG UT WOS:000236269800007 ER PT J AU Ferrare, R Feingold, G Ghan, S Ogren, J Schmid, B Schwartz, SE Sheridan, P AF Ferrare, R Feingold, G Ghan, S Ogren, J Schmid, B Schwartz, SE Sheridan, P TI Preface to special section: Atmospheric Radiation Measurement Program May 2003 Intensive Operations Period examining aerosol properties and radiative influences SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Editorial Material ID MEASURING LIGHT-ABSORPTION; WATER-VAPOR; SOLAR IRRADIANCE; CLOUD; INSTRUMENT; SURFACE; CALIBRATION; SATELLITE; TRANSPORT; CLOSURE AB [1] Atmospheric aerosols influence climate by scattering and absorbing radiation in clear air ( direct effects) and by serving as cloud condensation nuclei, modifying the microphysical properties of clouds, influencing radiation and precipitation development ( indirect effects). Much of present uncertainty in forcing of climate change is due to uncertainty in the relations between aerosol microphysical and optical properties and their radiative influences ( direct effects) and between microphysical properties and their ability to serve as cloud condensation nuclei at given supersaturations ( indirect effects). This paper introduces a special section that reports on a field campaign conducted at the Department of Energy Atmospheric Radiation Measurement site in north central Oklahoma in May 2003, examining these relations using in situ airborne measurements and surface-, airborne-, and space-based remote sensing. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. NOAA, Environm Technol Lab, Boulder, CO 80305 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. NASA, Ames Res Ctr, Bay Area Environm Res Inst, Moffett Field, CA 94035 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP NASA, Langley Res Ctr, MS 401A, Hampton, VA 23681 USA. EM richard.a.ferrare@nasa.gov RI Schwartz, Stephen/C-2729-2008; Feingold, Graham/B-6152-2009; Ogren, John/M-8255-2015; Ghan, Steven/H-4301-2011; Manager, CSD Publications/B-2789-2015 OI Schwartz, Stephen/0000-0001-6288-310X; Ogren, John/0000-0002-7895-9583; Ghan, Steven/0000-0001-8355-8699; NR 45 TC 18 Z9 18 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 MAR 11 PY 2006 VL 111 IS D5 AR D05S01 DI 10.1029/2005JD006908 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025MO UT WOS:000236270600007 ER PT J AU Panaitescu, A Meszaros, P Gehrels, N Burrows, D Nousek, J AF Panaitescu, A Meszaros, P Gehrels, N Burrows, D Nousek, J TI Analysis of the X-ray emission of nine Swift afterglows SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE radiation mechanisms : non-thermal; shock waves; ISM : jets and outflows; gamma-rays : bursts ID BURST AFTERGLOWS; LIGHT CURVES; OPTICAL AFTERGLOW; ENERGY INJECTION; FIREBALL MODEL; VIEWING ANGLE; GRB-990510; GRB-021211; PARAMETERS; DISCOVERY AB The X-ray light curves of nine Swift XRT afterglows (050126, 050128, 050219A, 050315, 050318, 050319, 050401, 050408 and 050505) display a complex behaviour: a steep t(-3.0 +/- 0.3) decay until similar to 400 s, followed by a significantly slower t(-0.65 +/- 0.20) fall-off, which at 0.2-2 day after the burst evolves into a t(-1.7 +/- 0.5) decay. We consider three possible models for the geometry of relativistic blast-waves (spherical outflows, non-spreading jets and spreading jets), two possible dynamical regimes for the forward shock (adiabatic and fully radiative), and we take into account a possible angular structure of the outflow and delayed energy injection in the blast-wave to identify the models which reconcile the X-ray light-curve decay with the slope of the X-ray continuum for each of the above three afterglow phases. By piecing together the various models for each phase in a way that makes physical sense, we identify possible models for the entire X-ray afterglow. The major conclusion of this work is that a long-lived episode of energy injection in the blast-wave, during which the shock energy increases at t(1.0 +/- 0.5), is required for five afterglows and could be at work in the other four as well. For some afterglows, there may be other mechanisms that can explain the t < 400 s fast falling-off X-ray light curve (e.g. the large-angle gamma-ray burst emission), the 400 s to 5 h slow decay (e.g. a structured outflow), or the steepening at 0.2-2 day (e.g. a jet-break, a collimated outflow transiting from a wind with a r(-3) radial density profile to a homogeneous or outward-increasing density region). Optical observations in conjunction with the X-ray can distinguish among these various models. Our simple tests allow the determination of the location of the cooling frequency relative to the X-ray domain and, thus, of the index of the electron power-law distribution with energy in the blast-wave. The resulting indices are clearly inconsistent with a universal value. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Panaitescu, A (reprint author), Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. EM alin@lanl.gov RI Gehrels, Neil/D-2971-2012 NR 54 TC 108 Z9 110 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 MAR 11 PY 2006 VL 366 IS 4 BP 1357 EP 1366 DI 10.1111/j.1365-2966.2005.09900.x PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 017MA UT WOS:000235696500016 ER PT J AU Rozo, E Zentner, AR Bertone, G Chen, J AF Rozo, E Zentner, AR Bertone, G Chen, J TI Statistics of magnification perturbations by substructure in the cold dark matter cosmological model SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; dark matter; galaxies : formation; galaxies : halos; galaxies : structure ID SMALL-SCALE STRUCTURE; MISSING-SATELLITES PROBLEM; GRAVITATIONAL LENSES; GALAXY FORMATION; GALACTIC SATELLITES; DENSITY PROFILES; LAMBDA-CDM; MICROLENSING VARIABILITY; SUBHALO POPULATIONS; IDENTIFYING LENSES AB We study the statistical properties of magnification perturbations by substructures in strong lensed systems using linear perturbation theory and an analytical substructure model including tidal truncation and a continuous substructure mass spectrum. We demonstrate that magnification perturbations are dominated by perturbers found within roughly a tidal radius of an image and that sizable magnification perturbations may arise from small, coherent contributions from several substructures within the lens halo. The rms fluctuation of the magnification perturbation is similar to 10% - 20%, and both the average and rms perturbations are sensitive to the mass spectrum and density profile of the perturbers. Interestingly, we find that relative to a smooth model of the same mass, the average magnification in clumpy models is lower ( higher) than that in smooth models for positive- parity ( negative- parity) images. This is opposite from what is observed if one assumes that the image magnification predicted by the best- fit smooth model of a lens is a good proxy for what the observed magnification would have been if substructures were absent. While it is possible for this discrepancy to be resolved via nonlinear perturbers, we argue that a more likely explanation is that the assumption that the best- fit lens model is a good proxy for the magnification in the absence of substructure is not correct. We conclude that a better theoretical understanding of the predicted statistical properties of magnification perturbations by CDM substructure is needed in order to affirm that CDM substructures have been unambiguously detected. C1 Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Kavli Inst Cosmol Phys, Chicago, IL 60637 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Rozo, E (reprint author), Univ Chicago, Dept Phys, 5640 S Ellis Ave, Chicago, IL 60637 USA. EM erozo@oddjob.uchicago.edu NR 100 TC 12 Z9 12 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 MAR 10 PY 2006 VL 639 IS 2 BP 573 EP 589 DI 10.1086/498737 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100001 ER PT J AU Elston, RJ Gonzalez, AH McKenzie, E Brodwin, M Brown, MJI Cardona, G Dey, A Dickinson, M Eisenhardt, PR Jannuzi, BT Lin, YT Mohr, JJ Raines, SN Stanford, SA Stern, D AF Elston, RJ Gonzalez, AH McKenzie, E Brodwin, M Brown, MJI Cardona, G Dey, A Dickinson, M Eisenhardt, PR Jannuzi, BT Lin, YT Mohr, JJ Raines, SN Stanford, SA Stern, D TI The flamingos extragalactic survey SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : evolution; infrared : galaxies ID GALAXY REDSHIFT SURVEY; STAR-FORMING GALAXIES; STELLAR MASS DENSITY; DIGITAL SKY SURVEY; SUBARU DEEP FIELD; K-BAND; NUMBER COUNTS; LUMINOSITY DENSITY; CLUSTER SURVEY; IMAGING SURVEY AB Using the Florida Multi-object Imaging Near-IR Grism Observational Spectrometer (FLAMINGOS), we have conducted the FLAMINGOS Extragalactic Survey (FLAMEX), a deep imaging survey covering 7.1 deg(2) within the 18.6 deg(2) NOAO Deep Wide-Field Survey (NDWFS) regions. FLAMEX is the first deep, wide-area, near-infrared survey to image in both the J and K-s filters, and is larger than any previous NIR survey of comparable depth. The intent of FLAMEX is to facilitate the study of galaxy and galaxy cluster evolution at 1 < z < 2 by providing rest-frame optical photometry for the massive galaxy population at this epoch. This effort is designed to yield a public data set that complements and augments the suite of existing surveys in the NDWFS fields. We present an overview of FLAMEX and initial results based on similar to 150,000 K-s-selected sources in the Bootes field. We describe the observations and reductions, quantify the data quality, and verify that the number counts are consistent with results from previous surveys. Finally, we comment on the utility of this sample for detailed study of the ERO population, and present one of the first spectroscopically confirmed z > 1 galaxy clusters detected using the joint FLAMEX, NDWFS, and Spitzer IRAC Shallow Survey data sets. C1 Univ Florida, Dept Astron, Gainesville, FL 32611 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Univ Illinois, Dept Astron, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. EM anthony@astro.ufl.edu RI Brown, Michael/B-1181-2015 OI Brown, Michael/0000-0002-1207-9137 NR 70 TC 91 Z9 91 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 MAR 10 PY 2006 VL 639 IS 2 BP 816 EP 826 DI 10.1086/499423 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100022 ER PT J AU Yong, D Aoki, W Lambert, DL Paulson, DB AF Yong, D Aoki, W Lambert, DL Paulson, DB TI Rubidium and lead abundances in giant stars of the globular clusters M13 and NGC 6752 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxy : abundances; globular clusters : individual (M13, NGC 6752); stars : abundances ID METAL-POOR STARS; NEUTRON-CAPTURE ELEMENTS; VERY-LOW METALLICITY; S-PROCESS; RED GIANTS; BRANCH STARS; DISPERSION SPECTROGRAPH; CHEMICAL-COMPOSITION; CROSS-SECTIONS; SELF-POLLUTION AB We present measurements of the neutron-capture elements Rb and Pb in five giant stars of the globular cluster NGC 6752 and Pb measurements in four giants of the globular cluster M13. The abundances were derived by comparing synthetic spectra with high-resolution, high signal-to-noise ratio spectra obtained using HDS on the Subaru telescope and MIKE on the Magellan telescope. The program stars span the range of the O-Al abundance variation. In NGC 6752, the mean abundances are [Rb/Fe] = -0.17 +/- 0.06 (sigma = 0.14), [Rb/Zr] = -0.12 +/- 0.06 (sigma = 0.13), and [Pb/Fe] = -0.17 +/- 0.04 (sigma = 0.08). In M13 the mean abundance is [Pb/Fe] = -0.28 +/- 0.03 (sigma = 0.06). Within the measurement uncertainties, we find no evidence for star-to-star variation for either Rb or Pb within these clusters. None of the abundance ratios [Rb/Fe], [Rb/Zr], or [Pb/Fe] are correlated with the Al abundance. NGC 6752 may have slightly lower abundances of [Rb/Fe] and [Rb/Zr] compared to the small sample of field stars at the same metallicity. For M13 and NGC 6752 the Pb abundances are in accord with predictions from a Galactic chemical evolution model. If metal-poor intermediate-mass asymptotic giant branch stars did produce the globular cluster abundance anomalies, then such stars do not synthesize significant quantities of Rb or Pb. Alternatively, if such stars do synthesize large amounts of Rb or Pb, then they are not responsible for the abundance anomalies seen in globular clusters. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Natl Astron Observ, Mitaka, Tokyo 1818588, Japan. Univ Texas, Dept Astron, Austin, TX 78712 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. EM yong@physics.unc.edu; aoki.wako@nao.ac.jp; dll@astro.as.utexas.edu; diane.b.paulson@gsfc.nasa.gov NR 74 TC 32 Z9 32 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 MAR 10 PY 2006 VL 639 IS 2 BP 918 EP 928 DI 10.1086/499580 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100029 ER PT J AU Baumgartner, WH Mushotzky, RF AF Baumgartner, WH Mushotzky, RF TI Oxygen abundances in the milky way using X-ray absorption measurements toward galaxy clusters SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; ISM : abundances; X-rays : ISM ID INTERSTELLAR-MEDIUM; XMM-NEWTON; SPACE-TELESCOPE; SPECTROSCOPY; SOLAR; CLOUDS; GAS; SPECTRUM; ELEMENTS; EDGE AB We present measurements of the oxygen abundance of the Milky Way's ISM by observing the K-shell X-ray photoionization edge toward galaxy clusters. This effect is most easily observed toward objects with Galactic columns (n(H)) of a few times 10(21) cm(-2). We measure X-ray column densities toward 11 clusters and find that at high Galactic columns above approximately 10(21) cm(-2) the X-ray columns are generally 1.5-3.0 times greater than the 21 cm H I columns, indicating that molecular clouds become an important contributor to nH at higher columns. We find the average ISM oxygen abundance to be (O/H) ( 4:85 +/- 0: 06); 10(-4), or 0.99 solar when using the most recent solar photospheric values. Since X-ray observations are sensitive to the total amount of oxygen present ( gas+dust), these results indicate a high gas to dust ratio. Also, the oxygen abundances along lines of sight through high Galactic columns ( nH) are the same as abundances through low columns, suggesting that the composition of denser clouds is similar to that of the more diffuse ISM. C1 CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Baumgartner, WH (reprint author), CALTECH, Space Radiat Lab, Mail Code 220-47,1200 E Calif Blvd, Pasadena, CA 91125 USA. EM wayne@srl.caltech.edu NR 46 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 MAR 10 PY 2006 VL 639 IS 2 BP 929 EP 940 DI 10.1086/499619 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100030 ER PT J AU Silverstone, MD Meyer, MR Mamajek, EE Hines, DC Hillenbrand, LA Najita, J Pascucci, I Bouwman, J Kim, JS Carpenter, JM Stauffer, JR Backman, DE Moro-Martin, A Henning, T Wolf, S Brooke, TY Padgett, DL AF Silverstone, MD Meyer, MR Mamajek, EE Hines, DC Hillenbrand, LA Najita, J Pascucci, I Bouwman, J Kim, JS Carpenter, JM Stauffer, JR Backman, DE Moro-Martin, A Henning, T Wolf, S Brooke, TY Padgett, DL TI Formation and evolution of planetary systems (FEPS): Primordial warm dust evolution from 3 to 30 Myr around sun-like stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; planetary systems : protoplanetary disks; stars : formation; stars : pre-main-sequence ID T-TAURI STARS; MAIN-SEQUENCE STARS; CIRCUMSTELLAR DISK MASSES; SCORPIUS OB ASSOCIATION; SPITZER-SPACE-TELESCOPE; YOUNG STELLAR OBJECTS; ARRAY CAMERA IRAC; SOLAR-TYPE STARS; ALL-SKY SURVEY; X-RAY SOURCES AB We present data obtained with the Infrared Array Camera ( IRAC) aboard the Spitzer Space Telescope ( Spitzer) for a sample of 74 young (t < 30 Myr old) Sun- like (0: 7 < M-*/M circle dot < 1: 5) stars. These are a subset of the observations that comprise the Spitzer Legacy science program entitled the Formation and Evolution of Planetary Systems ( FEPS). Using IRAC, we study the fraction of young stars that exhibit 3.6 - 8.0 mu m infrared emission in excess of that expected from the stellar photosphere, as a function of age from 3 to 30 Myr. The most straightforward interpretation of such excess emission is the presence of hot ( 300 - 1000 K) dust in the inner regions (< 3 AU) of a circumstellar disk. Five out of the 74 young stars show a strong infrared excess, four of which have estimated ages of 3 - 10 Myr. While we detect excesses from five optically thick disks and photospheric emission from the remainder of our sample, we do not detect any excess emission from optically thin disks at these wavelengths. We compare our results with accretion disk fractions detected in previous studies and use the ensemble results to place additional constraints on the dissipation timescales for optically thick, primordial disks. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Space Sci Inst, Boulder, CO 80301 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Max Planck Inst Astron, Heidelberg, Germany. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Princeton Univ, Princeton, NJ 08544 USA. RP Silverstone, MD (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. NR 72 TC 75 Z9 75 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 MAR 10 PY 2006 VL 639 IS 2 BP 1138 EP 1146 DI 10.1086/499418 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100049 ER PT J AU Beichman, CA Tanner, A Bryden, G Stapelfeldt, KR Werner, MW Rieke, GH Trilling, DE Lawler, S Gautier, TN AF Beichman, CA Tanner, A Bryden, G Stapelfeldt, KR Werner, MW Rieke, GH Trilling, DE Lawler, S Gautier, TN TI IRS spectra of solar-type stars: A search for asteroid belt analogs SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; comets : general; Kuiper Belt; minor planets, asteroids; planetary systems ID MULTIBAND IMAGING PHOTOMETER; SPITZER-SPACE-TELESCOPE; MAIN-SEQUENCE STARS; DEBRIS DISKS; PLANETARY SYSTEMS; DUSTY DEBRIS; VEGA; EVOLUTION; ORIGIN; EXCESS AB dWe report the results of a spectroscopic search for debris disks surrounding 41 nearby solar-type stars, including eight planet-bearing stars, using the Infrared Spectrometer ( IRS) on the Spitzer Space Telescope. With the accurate relative photometry of the IRS between 7 and 34 mu m we are able to look for excesses as small as similar to 2% of photospheric levels, with particular sensitivity to weak spectral features. For stars with no excess, the 3 sigma upper limit in a band at 30 - 34 mu m corresponds to similar to 75 times the brightness of our zodiacal dust cloud. Comparable limits at 8.5 - 13 mu m correspond to similar to 1400 times the brightness of our zodiacal dust cloud. These limits correspond to material located within the < 1 to similar to 5 AU region that, in our solar system, originates predominantly from debris associated with the asteroid belt. We find excess emission longward of similar to 25 mu m fromfive stars, of which four also show excess emission at 70 mu m. This emitting dust must be located in a region starting around 5 - 10 AU. One star has 70 mu m emission but no IRS excess. In this case, the emitting region must begin outside 10 AU; this star has a known radial velocity planet. Only two stars of the five show emission shortward of 25 mu m, where spectral features reveal the presence of a population of small, hot dust grains emitting in the 7 - 20 mu m band. One of these stars, HD 72905, is quite young ( 300 Myr), while the other, HD 69830, is older than 2 Gyr. The data presented here strengthen the results of previous studies to show that excesses at 25 mu m and shorter are rare: only 1 out of 40 stars older than 1 Gyr or similar to 2.5% shows an excess. Asteroid belts 10 - 30 times more massive than our own appear are rare among mature, solar-type stars. C1 CALTECH, Michelson Sci Ctr, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Beichman, CA (reprint author), CALTECH, Michelson Sci Ctr, MS 100-22, Pasadena, CA 91125 USA. EM chas@pop.jpl.nasa.gov RI Stapelfeldt, Karl/D-2721-2012 NR 43 TC 72 Z9 72 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 MAR 10 PY 2006 VL 639 IS 2 BP 1166 EP 1176 DI 10.1086/499424 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100052 ER PT J AU Turner, NJ Willacy, K Bryden, G Yorke, HW AF Turner, NJ Willacy, K Bryden, G Yorke, HW TI Turbulent mixing in the outer solar nebula SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; instabilities; MHD; solar system : formation; stars : formation ID RADIATION MAGNETOHYDRODYNAMICS CODE; 2 SPACE DIMENSIONS; T TAURI STARS; MAGNETOROTATIONAL INSTABILITY; PROTOPLANETARY DISKS; ACCRETION DISKS; NONLINEAR EVOLUTION; ASTROPHYSICAL FLOWS; DUST COAGULATION; 1ST DETECTION AB The effects of turbulence on the mixing of gases and dust in the outer solar nebula are examined using three-dimensional MHD calculations in the shearing-box approximation with vertical stratification. The turbulence is driven by the magnetorotational instability. The magnetic and hydrodynamic stresses in the turbulence correspond to an accretion time at the midplane about equal to the lifetimes of T Tauri disks, while accretion in the surface layers is 30 times faster. The mixing resulting from the turbulence is also fastest in the surface layers. The mixing rate is similar to the rate of radial exchange of orbital angular momentum, so that the Schmidt number is near unity. The vertical spreading of a trace species is well matched by solutions of a damped wave equation when the flow is horizontally averaged. The damped wave description can be used to inexpensively treat mixing in one-dimensional chemical models. However, even in calculations reaching a statistical steady state, the concentration at any given time varies substantially over horizontal planes, due to fluctuations in the rate and direction of the transport. In addition to mixing species that are formed under widely varying conditions, the turbulence intermittently forces the nebula away from local chemical equilibrium. The different transport rates in the surface layers and interior may affect estimates of the grain evolution and molecular abundances during the formation of the solar system. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Turner, NJ (reprint author), CALTECH, Jet Prop Lab, MS 169-506, Pasadena, CA 91109 USA. EM neal.turner@jpl.nasa.gov NR 49 TC 43 Z9 43 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 MAR 10 PY 2006 VL 639 IS 2 BP 1218 EP 1226 DI 10.1086/499486 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LK UT WOS:000235837100056 ER PT J AU Woo, R AF Woo, R TI Ultra-fine-scale filamentary structures in the outer corona and the solar magnetic field SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona ID QUIET-SUN; PHOTOSPHERIC NETWORK; WIND; TRANSPORT; FLUX; SPACECRAFT; STREAMERS; DYNAMICS; SPECTRUM; LOOPS AB Filamentary structures following magnetic field lines pervade the Sun's atmosphere and offer us insight into the solar magnetic field. Radio propagation measurements have shown that the smallest filamentary structures in the solar corona are more than 2 orders of magnitude finer than those seen in solar imaging. Here we use radio Doppler measurements to characterize their transverse density gradient and determine their finest scale in the outer corona at 20 - 30 R circle dot where open magnetic fields prevail. Filamentary structures overlying active regions have the steepest gradient and finest scale, while those overlying coronal holes have the shallowest gradient and least finest scale. Their organization by the underlying corona implies that these subresolution structures extend radially from the entire Sun, confirming that they trace the coronal magnetic field responsible for the radial expansion of the solar wind. That they are rooted all over the Sun elucidates the association between the magnetic field of the photosphere and that of the corona, as revealed by the similarity between the power spectra of the photospheric field and the coronal density fluctuations. This association along with the persistence of filamentary structures far from the Sun demonstrate that subresolution magnetic fields must play an important role not only in magnetic coupling of the photosphere and corona, but also in coronal heating and solar wind acceleration through the process of small-scale magnetic reconnection. They also explain why current widely used theoretical models that extrapolate photospheric magnetic fields into the corona do not predict the correct source of the solar wind. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Woo, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 238-725, Pasadena, CA 91109 USA. EM richard.woo@jpl.nasa.gov NR 57 TC 13 Z9 14 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 MAR 10 PY 2006 VL 639 IS 2 BP L95 EP L98 DI 10.1086/503029 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LL UT WOS:000235837200013 ER PT J AU Mayr, HG Mengel, JG Wolff, CL Porter, HS AF Mayr, HG Mengel, JG Wolff, CL Porter, HS TI QBO as potential amplifier of solar cycle influence SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID QUASI-BIENNIAL OSCILLATION; DOPPLER-SPREAD PARAMETERIZATION; WAVE MOMENTUM DEPOSITION; MIDDLE ATMOSPHERE; EQUATORIAL OSCILLATIONS; SEMIANNUAL OSCILLATION; INTERANNUAL VARIABILITY; SPECTRAL MODEL; GRAVITY-WAVES; KELVIN WAVE AB [1] The solar cycle (SC) effect in the lower atmosphere has been linked observationally to the quasi-biennial oscillation (QBO) of the zonal circulation. Salby and Callaghan (2000) in particular analyzed the QBO covering more than 40 years and found that it contains a large SC signature at 20 km. We discuss a 3D study in which we simulate the QBO under the influence of the SC. For a SC period of 10 years, the relative amplitude of radiative forcing is taken to vary with height: 0.2% (surface), 2% (50 km), 20% (100 km and above). This model produces in the lower stratosphere a relatively large modulation of the QBO, which appears to come from the SC and qualitatively agrees with the observations. The modulation of the QBO, with constant phase relative to the SC, is shown to persist at least for 50 years, and it is induced by a SC modulated annual oscillation that is hemispherically symmetric and confined to low latitudes (Mayr et al., 2005). C1 NASA, Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Furman Univ, Dept Comp Sci, Greenville, SC 29613 USA. RP Mayr, HG (reprint author), NASA, Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Mail Code 910-4, Greenbelt, MD 20771 USA. EM mayr@chapman.gsfc.nasa.gov OI Wolff, Charles/0000-0001-8854-507X NR 33 TC 16 Z9 16 U1 0 U2 4 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 MAR 10 PY 2006 VL 33 IS 5 AR L05812 DI 10.1029/2005GL025650 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 025MF UT WOS:000236269700005 ER PT J AU Zumberge, JF AF Zumberge, JF TI GPS: A military/civilian collaboration SO SCIENCE LA English DT Letter C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Zumberge, JF (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1377 EP 1378 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400018 PM 16527953 ER PT J AU Porco, CC Helfenstein, P Thomas, PC Ingersoll, AP Wisdom, J West, R Neukum, G Denk, T Wagner, R Roatsch, T Kieffer, S Turtle, E McEwen, A Johnson, TV Rathbun, J Veverka, J Wilson, D Perry, J Spitale, J Brahic, A Burns, JA DelGenio, AD Dones, L Murray, CD Squyres, S AF Porco, CC Helfenstein, P Thomas, PC Ingersoll, AP Wisdom, J West, R Neukum, G Denk, T Wagner, R Roatsch, T Kieffer, S Turtle, E McEwen, A Johnson, TV Rathbun, J Veverka, J Wilson, D Perry, J Spitale, J Brahic, A Burns, JA DelGenio, AD Dones, L Murray, CD Squyres, S TI Cassini observes the active South Pole of Enceladus SO SCIENCE LA English DT Article ID IMAGING SCIENCE; SOLAR-SYSTEM; E-RING; SATELLITES; SATURN; TECTONICS; EVOLUTION; EUROPA; WATER C1 Space Sci Inst, Cassini Imaging Cent Lab Operat, Boulder, CO 80301 USA. Univ London, Queen Mary, Astron Unit, London E1 4NS, England. SW Res Inst, Dept Space Studies, Boulder, CO 80302 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Paris 07, Ctr Etud Saclay, F-91191 Gif Sur Yvette, France. Univ Redlands, Dept Phys, Redlands, CA 92373 USA. Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. Univ Illinois, Dept Geol, Urbana, IL 61801 USA. German Aerosp Res Estab, Inst Planetary Res, D-12489 Berlin, Germany. Free Univ Berlin, Inst Geol Wissensch, D-12249 Berlin, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Porco, CC (reprint author), Space Sci Inst, Cassini Imaging Cent Lab Operat, 4750 Walnut St,Suite 205, Boulder, CO 80301 USA. EM carolyn@ciclops.org RI Del Genio, Anthony/D-4663-2012; Turtle, Elizabeth/K-8673-2012 OI Del Genio, Anthony/0000-0001-7450-1359; Turtle, Elizabeth/0000-0003-1423-5751 NR 42 TC 485 Z9 493 U1 23 U2 94 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1393 EP 1401 DI 10.1126/science.1123013 PG 9 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400030 PM 16527964 ER PT J AU Spencer, JR Pearl, JC Segura, M Flasar, FM Mamoutkine, A Romani, P Buratti, BJ Hendrix, AR Spilker, LJ Lopes, RMC AF Spencer, JR Pearl, JC Segura, M Flasar, FM Mamoutkine, A Romani, P Buratti, BJ Hendrix, AR Spilker, LJ Lopes, RMC TI Cassini encounters Enceladus: Background and the discovery of a south polar hot spot SO SCIENCE LA English DT Article ID SATURNS E-RING; SATELLITES; EVOLUTION; DYNAMICS; TETHYS; SYSTEM; MIMAS; RHEA; MASS C1 SW Res Inst, Dept Space Studies, Boulder, CO 80302 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Spencer, JR (reprint author), SW Res Inst, Dept Space Studies, 1050 Walnut St,Suite 400, Boulder, CO 80302 USA. EM spencer@boulder.swri.edu RI Flasar, F Michael/C-8509-2012; Romani, Paul/D-2729-2012; Lopes, Rosaly/D-1608-2016 OI Lopes, Rosaly/0000-0002-7928-3167 NR 36 TC 264 Z9 267 U1 6 U2 31 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1401 EP 1405 DI 10.1126/science.1121661 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400031 PM 16527965 ER PT J AU Dougherty, MK Khurana, KK Neubauer, FM Russell, CT Saur, J Leisner, JS Burton, ME AF Dougherty, MK Khurana, KK Neubauer, FM Russell, CT Saur, J Leisner, JS Burton, ME TI Identification of a dynamic atmosphere at Enceladus with the Cassini magnetometer SO SCIENCE LA English DT Article ID IO; SYSTEM; SATELLITES; ENGINE; SPACE C1 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. Univ Cologne, Inst Geophys & Meteorol, D-50923 Cologne, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Dougherty, MK (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Prince Consort Rd, London SW7 2AZ, England. EM m.dougherty@imperial.ac.uk NR 15 TC 194 Z9 196 U1 9 U2 27 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1406 EP 1409 DI 10.1126/science.1120985 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400032 PM 16527966 ER PT J AU Tokar, RL Johnson, RE Hill, TW Pontius, DH Kurth, WS Crary, FJ Young, DT Thomsen, MF Reisenfeld, DB Coates, AJ Lewis, GR Sittler, EC Gurnett, DA AF Tokar, RL Johnson, RE Hill, TW Pontius, DH Kurth, WS Crary, FJ Young, DT Thomsen, MF Reisenfeld, DB Coates, AJ Lewis, GR Sittler, EC Gurnett, DA TI The interaction of the atmosphere of Enceladus with Saturn's plasma SO SCIENCE LA English DT Article ID CASSINI; SPECTROMETER; ION C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Virginia, Charlottesville, VA 22904 USA. Rice Univ, Houston, TX 77251 USA. Birmingham So Coll, Birmingham, AL 35254 USA. Univ Iowa, Iowa City, IA 52242 USA. SW Res Inst, San Antonio, TX 78228 USA. Univ Montana, Missoula, MT 59812 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Tokar, RL (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM rlt@lanl.gov RI Coates, Andrew/C-2396-2008; Reisenfeld, Daniel/F-7614-2015; OI Coates, Andrew/0000-0002-6185-3125; Kurth, William/0000-0002-5471-6202 NR 12 TC 133 Z9 133 U1 0 U2 7 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1409 EP 1412 DI 10.1126/science.1121061 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400033 PM 16527967 ER PT J AU Waite, JH Combi, MR Ip, WH Cravens, TE McNutt, RL Kasprzak, W Yelle, R Luhmann, J Niemann, H Gell, D Magee, B Fletcher, G Lunine, J Tseng, WL AF Waite, JH Combi, MR Ip, WH Cravens, TE McNutt, RL Kasprzak, W Yelle, R Luhmann, J Niemann, H Gell, D Magee, B Fletcher, G Lunine, J Tseng, WL TI Cassini ion and neutral mass spectrometer: Enceladus plume composition and structure SO SCIENCE LA English DT Article ID SPECTROSCOPY; PARTICLES; SATURN; ICE C1 Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Natl Cent Univ, Inst Astron, Chungli 32054, Taiwan. Natl Cent Univ, Inst Space Sci, Chungli 32054, Taiwan. Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. RP Waite, JH (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. RI Combi, Michael/J-1697-2012; McNutt, Ralph/E-8006-2010 OI Combi, Michael/0000-0002-9805-0078; McNutt, Ralph/0000-0002-4722-9166 NR 23 TC 304 Z9 309 U1 11 U2 64 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1419 EP 1422 DI 10.1126/science.1121290 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400036 PM 16527970 ER PT J AU Hansen, CJ Esposito, L Stewart, AIF Colwell, J Hendrix, A Pryor, W Shemansky, D West, R AF Hansen, CJ Esposito, L Stewart, AIF Colwell, J Hendrix, A Pryor, W Shemansky, D West, R TI Enceladus' water vapor plume SO SCIENCE LA English DT Article ID SATURNS E-RING; OSCILLATOR-STRENGTHS; SYSTEM; ATMOSPHERES; PLASMA C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Colorado, Lab Air & Space Phys, Boulder, CO 80303 USA. Space Environm Technol, Pasadena, CA 91107 USA. Cent Arizona Coll, Coolidge, AZ 85228 USA. RP Hansen, CJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Candice.j.Hansen@jpl.nasa.gov NR 22 TC 263 Z9 265 U1 11 U2 48 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1422 EP 1425 DI 10.1126/science.1121254 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400037 PM 16527971 ER PT J AU Brown, RH Clark, RN Buratti, BJ Cruikshank, DP Barnes, JW Mastrapa, RME Bauer, J Newman, S Momary, T Baines, KH Bellucci, G Capaccioni, F Cerroni, P Combes, M Coradini, A Drossart, P Formisano, V Jaumann, R Langevin, Y Matson, DL McCord, TB Nelson, RM Nicholson, PD Sicardy, B Sotin, C AF Brown, RH Clark, RN Buratti, BJ Cruikshank, DP Barnes, JW Mastrapa, RME Bauer, J Newman, S Momary, T Baines, KH Bellucci, G Capaccioni, F Cerroni, P Combes, M Coradini, A Drossart, P Formisano, V Jaumann, R Langevin, Y Matson, DL McCord, TB Nelson, RM Nicholson, PD Sicardy, B Sotin, C TI Composition and physical properties of Enceladus' surface SO SCIENCE LA English DT Article ID KINETIC INHIBITION; MAGNETIC-FIELD; ICY SATELLITES; OUTER PLANETS; N-2 REDUCTION; SOLAR-SYSTEM; H2O ICE; CHEMISTRY; NEBULA; CO C1 Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. US Geol Survey, Denver, CO 80225 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Inst Fis Spazio Interplanetario, I-0133 Rome, Italy. Ist Astrofis Spaziale, I-0133 Rome, Italy. Observ Paris, F-92195 Meudon, France. Deutsch Zentrum Luft & Raumfahrt, D-12489 Berlin, Germany. Univ Paris, Inst Astrophys Spatiale, F-91405 Orsay, France. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Univ Nantes, F-44072 Nantes, France. RP Brown, RH (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. RI Barnes, Jason/B-1284-2009; OI Barnes, Jason/0000-0002-7755-3530; Cerroni, Priscilla/0000-0003-0239-2741; Bellucci, Giancarlo/0000-0003-0867-8679; Capaccioni, Fabrizio/0000-0003-1631-4314 NR 26 TC 128 Z9 129 U1 15 U2 39 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1425 EP 1428 DI 10.1126/science.1121031 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400038 PM 16527972 ER PT J AU Sunshine, JM A'Hearn, MF Groussin, O Li, JY Belton, MJS Delamere, WA Kissel, J Klaasen, KP McFadden, LA Meech, KJ Melosh, HJ Schultz, PH Thomas, PC Veverka, J Yeomans, DK Busko, IC Desnoyer, M Farnham, TL Feaga, LM Hampton, DL Lindler, DJ Lisse, CM Wellnitz, DD AF Sunshine, JM A'Hearn, MF Groussin, O Li, JY Belton, MJS Delamere, WA Kissel, J Klaasen, KP McFadden, LA Meech, KJ Melosh, HJ Schultz, PH Thomas, PC Veverka, J Yeomans, DK Busko, IC Desnoyer, M Farnham, TL Feaga, LM Hampton, DL Lindler, DJ Lisse, CM Wellnitz, DD TI Exposed water ice deposits on the surface of comet 9P/Tempel 1 SO SCIENCE LA English DT Article ID SATURNS MOON PHOEBE; DEEP-IMPACT; INFRARED-SPECTROSCOPY; MU-M; NUCLEUS; GRAINS AB We report the direct detection of solid water ice deposits exposed on the surface of comet 9P/Tempel 1, as observed by the Deep Impact mission. Three anomalously colored areas are shown to include water ice on the basis of their near-infrared spectra, which include diagnostic water ice absorptions at wavelengths of 1.5 and 2.0 micrometers. These absorptions are well modeled as a mixture of nearby non-ice regions and 3 to 6% water ice particles 10 to 50 micrometers in diameter. These particle sizes are larger than those ejected during the impact experiment, which suggests that the surface deposits are loose aggregates. The total area of exposed water ice is substantially less than that required to support the observed ambient outgassing from the comet, which likely has additional source regions below the surface. C1 Sci Applicat Int Corp, Chantilly, VA 20151 USA. Univ Maryland, College Pk, MD 20742 USA. Belton Space Explorat Initiat, Tucson, AZ 85716 USA. Delamere Support Serv, Boulder, CO 80301 USA. Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Arizona, Tucson, AZ 85721 USA. Brown Univ, Providence, RI USA. Cornell Univ, Ithaca, NY 14853 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Ball Aerosp & Technol Corp, Boulder, CO 80301 USA. Sigma Sci, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP Sunshine, JM (reprint author), Sci Applicat Int Corp, Chantilly, VA 20151 USA. EM sunshinej@saic.com RI Wellnitz, Dennis/B-4080-2012; McFadden, Lucy-Ann/I-4902-2013; Lisse, Carey/B-7772-2016 OI McFadden, Lucy-Ann/0000-0002-0537-9975; Lisse, Carey/0000-0002-9548-1526 NR 30 TC 130 Z9 132 U1 2 U2 9 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1453 EP 1455 DI 10.1126/science.1123632 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400046 PM 16456037 ER PT J AU Grebmeier, JM Overland, JE Moore, SE Farley, EV Carmack, EC Cooper, LW Frey, KE Helle, JH McLaughlin, FA McNutt, SL AF Grebmeier, JM Overland, JE Moore, SE Farley, EV Carmack, EC Cooper, LW Frey, KE Helle, JH McLaughlin, FA McNutt, SL TI A major ecosystem shift in the northern Bering Sea SO SCIENCE LA English DT Article ID LATE WINTER; ICE COVER; PACK ICE; SHELF; WATER; POLYNYA; BENTHOS; SUMMER; ALASKA C1 Univ Tennessee, Dept Ecol & Evolutionary Biol, Marine Biogeochem & Ecol Grp, Knoxville, TN 37932 USA. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. NOAA, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. NOAA, Auke Bay Lab, Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Juneau, AK 99801 USA. Fisheries & Oceans Canada, Inst Ocean Sci, Sidney, BC V8L 4B2, Canada. Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. Univ Alaska Fairbanks, Inst Geophys, Fairbanks, AK 99775 USA. RP Grebmeier, JM (reprint author), Univ Tennessee, Dept Ecol & Evolutionary Biol, Marine Biogeochem & Ecol Grp, 10515 Res Dr,Bldg A,Suite 100, Knoxville, TN 37932 USA. EM jgrebmei@utk.edu RI Cooper, Lee/E-5251-2012; Grebmeier, Jacqueline/L-9805-2013 OI Cooper, Lee/0000-0001-7734-8388; Grebmeier, Jacqueline/0000-0001-7624-3568 NR 29 TC 428 Z9 444 U1 22 U2 161 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 MAR 10 PY 2006 VL 311 IS 5766 BP 1461 EP 1464 DI 10.1126/science.1121365 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 022BJ UT WOS:000236029400049 PM 16527980 ER PT J AU Hallar, AG Strawa, AW Schmid, B Andrews, E Ogren, J Sheridan, P Ferrare, R Covert, D Elleman, R Jonsson, H Bokarius, K Luu, A AF Hallar, AG Strawa, AW Schmid, B Andrews, E Ogren, J Sheridan, P Ferrare, R Covert, D Elleman, R Jonsson, H Bokarius, K Luu, A TI Atmospheric Radiation Measurements Aerosol Intensive Operating Period: Comparison of aerosol scattering during coordinated flights SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID OPTICAL-PROPERTIES; CAVITY RING; ACE-ASIA; IN-SITU; INTEGRATING NEPHELOMETER; SAMPLING CHARACTERISTICS; PARTICLE-SIZE; AIRCRAFT; INLET; CLOUD AB [1] In May 2003, a Twin Otter airplane, equipped with instruments for making in situ measurements of aerosol optical properties, was deployed during the Atmospheric Radiation Measurements ( ARM) Program's Aerosol Intensive Operational Period in Oklahoma. Several of the Twin Otter flights were flown in formation with an instrumented light aircraft (Cessna 172XP) that makes routine in situ aerosol profile flights over the site. This paper presents comparisons of measured scattering coefficients at 467 nm, 530 nm, and 675 nm between identical commercial nephelometers aboard each aircraft. Overall, the agreement between the two nephelometers decreases with longer wavelength. During the majority of the flights, the Twin Otter flew with a diffuser inlet while the Cessna had a 1 mm impactor, allowing for an estimation of the fine mode fraction aloft. The fine mode fraction aloft was then compared to the results of a ground-based nephelometer. Comparisons are also provided in which both nephelometers operated with identical 1 mm impactors. These scattering coefficient comparisons are favorable at the longer wavelengths (i.e., 530 nm and 675 nm), yet differed by approximately 30% at 467 nm. Mie scattering calculations were performed using size distribution measurements, made during the level flight legs. Results are also presented from Cadenza, a new continuous wave cavity ring-down (CW-CRD) instrument, which compared favorably (i.e., agreed within 2%) with data from other instruments aboard the Twin Otter. With this paper, we highlight the significant implications of coarse mode ( larger than 1 mm) aerosol aloft with respect to aerosol optical properties. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. CNR, Associateship Program, Washington, DC 20418 USA. Bay Area Environm Res Inst, Sonoma, CA 95476 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Ctr Interdisciplinary Remotely Piloted Aircraft S, Marina Del Rey, CA 93933 USA. RP Hallar, AG (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM ahallar@mail.arc.nasa.gov RI Hallar, Anna Gannet/I-9104-2012; Ogren, John/M-8255-2015 OI Hallar, Anna Gannet/0000-0001-9972-0056; Ogren, John/0000-0002-7895-9583 NR 50 TC 18 Z9 18 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 MAR 9 PY 2006 VL 111 IS D5 AR D05S09 DI 10.1029/2005JD006250 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025MM UT WOS:000236270400003 ER PT J AU Pan, LL Konopka, P Browell, EV AF Pan, LL Konopka, P Browell, EV TI Observations and model simulations of mixing near the extratropical tropopause SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERE-TROPOSPHERE EXCHANGE; CHEMICAL LAGRANGIAN MODEL; DIFFERENTIAL ABSORPTION LIDAR; POTENTIAL VORTICITY; LOWERMOST STRATOSPHERE; MASS-EXCHANGE; WATER-VAPOR; ART.; OZONE; TRANSPORT AB [1] Mixing of stratospheric and tropospheric air plays an essential role in the stratosphere-troposphere exchange (STE) of chemical species. Although evidence of mixing is frequently observed, quantifying its effect has been a significant challenge. We present an analysis using both observations and modeling tools to address the issues of where mixing occurs and how models can quantify its effect to STE across the extratropical tropopause. The data are from remote and in situ measurements on board the NASA DC-8 during the Subsonic Assessment: Ozone and Nitrogen Oxides Experiment (SONEX). The model simulations use the Chemical Lagrangian Model of the Stratosphere (CLaMS). Our analyses use tracer correlations together with lidar measurements of ozone cross sections to characterize the spatial extent of the observed mixing. The results also serve to identify the air mass that is involved in an irreversible exchange. Results of the CLaMS simulations of lidar and in situ observations for a case observed on 29 October 1997 demonstrate the model's ability to characterize mixing near the tropopause. The results also indicate that using the shear and deformation in large-scale winds, we can reproduce the observed mixing and the overall features of the stratospheric intrusion. An artificial tracer is used to quantify the transport between the stratosphere and troposphere, to track the preferred location and the cumulative effect of mixing. These results demonstrate progress toward modeling mixing and STE using Lagrangian models and show the potential of the CLaMS model in quantifying the effect of mixing on the chemical composition of the upper tropospheric and lower stratospheric region. C1 Natl Ctr Atmospher Res, Boulder, CO 80305 USA. Inst Stratospher Chem ICG 1, D-52425 Julich, Germany. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Pan, LL (reprint author), Natl Ctr Atmospher Res, Boulder, CO 80305 USA. EM liwen@ucar.edu RI Pan, Laura/A-9296-2008; Konopka, Paul/A-7329-2013 OI Pan, Laura/0000-0001-7377-2114; NR 35 TC 28 Z9 29 U1 0 U2 4 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 MAR 9 PY 2006 VL 111 IS D5 AR D05106 DI 10.1029/2005JD006480 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025MM UT WOS:000236270400006 ER PT J AU Dong, D Fang, P Bock, Y Webb, F Prawirodirdjo, L Kedar, S Jamason, P AF Dong, D Fang, P Bock, Y Webb, F Prawirodirdjo, L Kedar, S Jamason, P TI Spatiotemporal filtering using principal component analysis and Karhunen-Loeve expansion approaches for regional GPS network analysis SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID TERRESTRIAL REFERENCE FRAME; GLOBAL POSITIONING SYSTEM; 1992 LANDERS EARTHQUAKE; CRUSTAL VELOCITY-FIELD; BASE-LINE MEASUREMENTS; SOUTHERN CALIFORNIA; TIME-SERIES; LOS-ANGELES; PLATE VELOCITIES; SUBDUCTION ZONE AB [1] Spatial filtering is an effective way to improve the precision of coordinate time series for regional GPS networks by reducing so-called common mode errors, thereby providing better resolution for detecting weak or transient deformation signals. The commonly used approach to regional filtering assumes that the common mode error is spatially uniform, which is a good approximation for networks of hundreds of kilometers extent, but breaks down as the spatial extent increases. A more rigorous approach should remove the assumption of spatially uniform distribution and let the data themselves reveal the spatial distribution of the common mode error. The principal component analysis (PCA) and the Karhunen-Loeve expansion (KLE) both decompose network time series into a set of temporally varying modes and their spatial responses. Therefore they provide a mathematical framework to perform spatiotemporal filtering. We apply the combination of PCA and KLE to daily station coordinate time series of the Southern California Integrated GPS Network (SCIGN) for the period 2000 to 2004. We demonstrate that spatially and temporally correlated common mode errors are the dominant error source in daily GPS solutions. The spatial characteristics of the common mode errors are close to uniform for all east, north, and vertical components, which implies a very long wavelength source for the common mode errors, compared to the spatial extent of the GPS network in southern California. Furthermore, the common mode errors exhibit temporally nonrandom patterns. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif San Diego, Scripps Inst Oceanog, Inst Geophys & Planetary Phys, La Jolla, CA 92093 USA. RP CALTECH, Jet Prop Lab, MS 238-600,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM danan.dong@jpl.nasa.gov; pfang@pgga.ucsd.edu; ybock@ucsd.edu; frank.h.webb@jpl.nasa.gov; linette@gpsmail.ucsd.edu; sharon.kedar@jpl.nasa.gov; pjamason@gpsmail.ucsd.edu NR 67 TC 74 Z9 89 U1 2 U2 15 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 9 PY 2006 VL 111 IS B3 AR B03405 DI 10.1029/2005JB003806 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 025MX UT WOS:000236271500003 ER PT J AU Narayanan, SR Yen, SP Liu, L Greenbaum, SG AF Narayanan, SR Yen, SP Liu, L Greenbaum, SG TI Anhydrous proton-conducting polymeric electrolytes for fuel cells SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID COMPOSITE MEMBRANES; NAFION(R); OPERATION; IMIDAZOLE; HUMIDITY AB The need to design proton-conducting electrolytes for fuel cells operating at temperatures of 120 degrees C and above has prompted the investigation of various "water-free" polymeric materials. The present study investigates the properties of "water-free" proton-conducting membranes prepared from high-molecular-weight polymeric organic amine salts. Specifically, the properties of bisulfates and dihydrogenphosphates of poly-2-vinylpyridine (P2VP), poly-4-vinylpyridine (P4VP), and polyvinylimidazoline (PVI) have been investigated over the temperature range of 25-180 degrees C. Nanocomposites of these polymeric organic amine salts and hydroxylated silica have also been investigated in this study. These polymers are found to be stable and proton-conducting at temperatures up to 200 degrees C. In all the polymer examples studied herein, the phosphates are more conducting than the bisulfates. The activation energy for ionic conduction was found to decrease with increasing temperature, and this is associated with the increased polymer mobility and ionization of the proton. This is confirmed by the high degree of motional narrowing that is observed in proton NMR experiments. The measured values of conductivity and the differences in pK(a) values of the polymeric organic amine and the mineral acid are clearly correlated. This observation provides the basis for the design of other water-free acid-base polymer systems with enhanced proton conductivity. The results presented here suggest that anhydrous polymer systems based on acid-base polymer salts could be combined with short-range proton conductors such as nanoparticulate silica to achieve acceptable conductivity over the entire temperature range. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CUNY Hunter Coll, Dept Phys, New York, NY 10021 USA. RP CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM s.r.narayanan@jpl.nasa.gov FU NCRR NIH HHS [RR-03037] NR 23 TC 46 Z9 47 U1 2 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 9 PY 2006 VL 110 IS 9 BP 3942 EP 3948 DI 10.1021/jp054167w PG 7 WC Chemistry, Physical SC Chemistry GA 020WS UT WOS:000235944500020 PM 16509680 ER PT J AU Cusumano, G Mangano, V Chincarini, G Panaitescu, A Burrows, DN LaParola, V Sakamoto, T Campana, S Mineo, T Tagliaferri, G Angelini, L Barthelemy, SD Beardmore, AP Boyd, PT Cominsky, LR Gronwall, C Fenimore, EE Gehrels, N Giommi, P Goad, M Hurley, K Kennea, JA Mason, KO Marshall, F Meszaros, P Nousek, JA Osborne, JP Palmer, DM Roming, PWA Wells, A White, NE Zhang, B AF Cusumano, G Mangano, V Chincarini, G Panaitescu, A Burrows, DN LaParola, V Sakamoto, T Campana, S Mineo, T Tagliaferri, G Angelini, L Barthelemy, SD Beardmore, AP Boyd, PT Cominsky, LR Gronwall, C Fenimore, EE Gehrels, N Giommi, P Goad, M Hurley, K Kennea, JA Mason, KO Marshall, F Meszaros, P Nousek, JA Osborne, JP Palmer, DM Roming, PWA Wells, A White, NE Zhang, B TI Huge explosion in the early Universe SO NATURE LA English DT Editorial Material C1 INAF Ist Astrofis Spaziale & Fis Cosm Palermo, I-90146 Palermo, Italy. INAF Osservatorio Astron Brera, I-23807 Merate, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CNR, Washington, DC 20418 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Sonoma State Univ, Dept Phys & Astron, Rohnert Pk, CA 94928 USA. ASI Sci Data Ctr, I-00044 Frascati, Italy. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Cusumano, G (reprint author), INAF Ist Astrofis Spaziale & Fis Cosm Palermo, I-90146 Palermo, Italy. EM cusumano@ifc.inaf.it RI White, Nicholas/B-6428-2012; Boyd, Patricia/D-3274-2012; Gehrels, Neil/D-2971-2012; OI White, Nicholas/0000-0003-3853-3462; Cusumano, Giancarlo/0000-0002-8151-1990 NR 11 TC 62 Z9 64 U1 1 U2 1 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAR 9 PY 2006 VL 440 IS 7081 BP 164 EP 164 DI 10.1038/440164a PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 019MC UT WOS:000235839500032 PM 16525462 ER PT J AU Haislip, JB Nysewander, MC Reichart, DE Levan, A Tanvir, N Cenko, SB Fox, DB Price, PA Castro-Tirado, AJ Gorosabel, J Evans, CR Figueredo, E MacLeod, CL Kirschbrown, JR Jelinek, M Guziy, S Postigo, AD Cypriano, ES LaCluyze, A Graham, J Priddey, R Chapman, R Rhoads, J Fruchter, AS Lamb, DQ Kouveliotou, C Wijers, RAMJ Bayliss, MB Schmidt, BP Soderberg, AM Kulkarni, SR Harrison, FA Moon, DS Gal-Yam, A Kasliwal, MM Hudec, R Vitek, S Kubanek, P Crain, JA Foster, AC Clemens, JC Bartelme, JW Canterna, R Hartmann, DH Henden, AA Klose, S Park, HS Williams, GG Rol, E O'Brien, P Bersier, D Prada, F Pizarro, S Maturana, D Ugarte, P Alvarez, A Fernandez, AJM Jarvis, MJ Moles, M Alfaro, E Ivarsen, KM Kumar, ND Mack, CE Zdarowicz, CM Gehrels, N Barthelmy, S Burrows, DN AF Haislip, JB Nysewander, MC Reichart, DE Levan, A Tanvir, N Cenko, SB Fox, DB Price, PA Castro-Tirado, AJ Gorosabel, J Evans, CR Figueredo, E MacLeod, CL Kirschbrown, JR Jelinek, M Guziy, S Postigo, AD Cypriano, ES LaCluyze, A Graham, J Priddey, R Chapman, R Rhoads, J Fruchter, AS Lamb, DQ Kouveliotou, C Wijers, RAMJ Bayliss, MB Schmidt, BP Soderberg, AM Kulkarni, SR Harrison, FA Moon, DS Gal-Yam, A Kasliwal, MM Hudec, R Vitek, S Kubanek, P Crain, JA Foster, AC Clemens, JC Bartelme, JW Canterna, R Hartmann, DH Henden, AA Klose, S Park, HS Williams, GG Rol, E O'Brien, P Bersier, D Prada, F Pizarro, S Maturana, D Ugarte, P Alvarez, A Fernandez, AJM Jarvis, MJ Moles, M Alfaro, E Ivarsen, KM Kumar, ND Mack, CE Zdarowicz, CM Gehrels, N Barthelmy, S Burrows, DN TI A photometric redshift of z = 6.39 +/- 0.12 for GRB 050904 SO NATURE LA English DT Article ID GAMMA-RAY BURST; OPTICAL AFTERGLOW; RADIATION; EMISSION; PROBE AB Gamma-ray bursts (GRBs) and their afterglows are the most brilliant transient events in the Universe. Both the bursts themselves and their afterglows have been predicted to be visible out to redshifts of z approximate to 20, and therefore to be powerful probes of the early Universe(1,2). The burst GRB 000131, at z = 4.50, was hitherto the most distant such event identified(3). Here we report the discovery of the bright near-infrared afterglow of GRB 050904 (ref. 4). From our measurements of the near-infrared afterglow, and our failure to detect the optical afterglow, we determine the photometric redshift of the burst to be z = 6.39(-0.12)(+0.11) (refs 5-7). Subsequently, it was measured(8) spectroscopically to be z = 6.29 +/- 0.01, in agreement with our photometric estimate. These results demonstrate that GRBs can be used to trace the star formation, metallicity, and reionization histories of the early Universe. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Inst Astrofis Andalucia, E-18080 Granada, Spain. Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508900 Sao Paulo, Brazil. So Observ Astrophys, La Serena, Chile. Lab Nacl Astrofis, BR-37500000 Itajuba, MG, Brazil. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, George C Marshall Space Flight Ctr, Natl Space Sci Technol Ctr, Huntsville, AL 35805 USA. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Canberra, ACT 2611, Australia. CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. Acad Sci Czech Republ, Inst Astron, CS-25165 Ondrejov, Czech Republic. Czech Tech Univ, Fac Electrotech, Prague 12135, Czech Republic. Integral Sci Data Ctr, CH-1290 Versoix, Switzerland. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82072 USA. Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA. Amer Assoc Variable Star Observers, Cambridge, MA 02138 USA. Thueringer Landessternwarte Tautenburg, D-07778 Tautenburg, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Arizona, Multiple Mirror Telescope Observ, Tucson, AZ 85721 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Reichart, DE (reprint author), Univ N Carolina, Dept Phys & Astron, Campus Box 3255, Chapel Hill, NC 27599 USA. EM reichart@physics.unc.edu RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; Cypriano, Eduardo/C-7293-2012; Kirschbrown, Justin/B-3636-2013; Kubanek, Petr/G-7209-2014; Hudec, Rene/G-9018-2014; Vitek, Stanislav/B-3332-2015; Evans, Charles/M-2377-2015; Jelinek, Martin/E-5290-2016 OI Wijers, Ralph/0000-0002-3101-1808; Schmidt, Brian/0000-0001-6589-1287; de Ugarte Postigo, Antonio/0000-0001-7717-5085; Schmidt, Brian/0000-0002-8538-9195; Alfaro, E. J./0000-0002-2234-7035; Castro-Tirado, A. J./0000-0003-2999-3563; Vitek, Stanislav/0000-0002-3185-1495; Evans, Charles/0000-0001-5578-1033; Jelinek, Martin/0000-0003-3922-7416 NR 30 TC 111 Z9 112 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 MAR 9 PY 2006 VL 440 IS 7081 BP 181 EP 183 DI 10.1038/nature04552 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 019MC UT WOS:000235839500038 PM 16525465 ER PT J AU Gasso, S O'Neill, N AF Gasso, S O'Neill, N TI Comparisons of remote sensing retrievals and in situ measurements of aerosol fine mode fraction during ACE-Asia SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OPTICAL-PROPERTIES; ALGORITHM; DEPTH AB [1] We present sunphotometer-retrieved and in situ fine mode fractions (FMF) measured onboard the same aircraft during the ACE-Asia experiment. Comparisons indicate that the latter can be used to identify whether the aerosol under observation is dominated by a mixture of modes or a single mode. Differences between retrieved and in situ FMF range from 5-20%. When profiles contained multiple layers of aerosols, the retrieved and measured FMF were segregated by layers. The comparison of layered and total FMF from the same profile indicates that columnar values are intermediate to those derived from layers. As a result, a remotely sensed FMF cannot be used to distinguish whether the aerosol under observation is composed of layers each with distinctive modal features or all layers with the same modal features. Thus, the use of FMF in multiple layer environments does not provide unique information on the aerosol under observation. C1 Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Univ Sherbrooke, Ctr Applicat & Rech Teledetect, Sherbrooke, PQ J1K 2R1, Canada. RP Gasso, S (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. EM santiago@climate.gsfc.nasa.gov RI Gasso, Santiago/H-9571-2014 OI Gasso, Santiago/0000-0002-6872-0018 NR 17 TC 6 Z9 6 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 MAR 8 PY 2006 VL 33 IS 5 AR L05807 DI 10.1029/2005GL024926 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 025MC UT WOS:000236269400002 ER PT J AU Vallina, SM Simo, R Gasso, S AF Vallina, SM Simo, R Gasso, S TI What controls CCN seasonality in the Southern Ocean? A statistical analysis based on satellite-derived chlorophyll and CCN and model-estimated OH radical and rainfall SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article ID CLOUD CONDENSATION NUCLEI; SEA-SALT-SULFATE; EXPERIMENT ACE 1; MARINE BOUNDARY-LAYER; AEROSOL OPTICAL-PROPERTIES; ATMOSPHERIC SULFUR; DIMETHYL SULFIDE; WIND-SPEED; SIZE DISTRIBUTIONS; OXIDATION-PRODUCTS AB [1] A 3-year time series set (from January 2002 to December 2004) of monthly means of satellite-derived chlorophyll (CHL) and cloud condensation nuclei (CCN), as well as model outputs of hydroxyl radical (OH), rainfall amount ( RAIN), and wind speed (WIND) for the Southern Ocean (SO, 40 degrees S-60 degrees S) is analyzed in order to explain CCN seasonality. Chlorophyll is used as a proxy for oceanic dimethylsulfide (DMS) emissions since both climatological aqueous DMS and atmospheric methanesulfonate (MSA) concentrations are tightly coupled with chlorophyll seasonality over the Southern Ocean. OH is included as the main atmospheric oxidant of DMS to produce CCN, and rainfall amount as the main loss factor for CCN through aerosol scavenging. Wind speed is used as a proxy for sea salt (SS) particles production. The CCN concentration seasonality is characterized by a clear pattern of higher values during austral summer and lower values during austral winter. Linear and multiple regression analyses reveal high significant correlations between CCN and the product of chlorophyll and OH (in phase) and rainfall amount (in antiphase). Also, CCN concentrations are anticorrelated with wind speed, which shows very little variability and a slight wintertime increase, in agreement with the sea salt seasonality reported in the literature. Finally, the fraction of the total aerosol optical depth contributed by small particles (ETA) exhibits a seasonality with a 3.5-fold increase from austral winter to austral summer. The biogenic contribution to CCN is estimated to vary between 35% (winter) and 80% (summer). Sea salt particles, although contributing an important fraction of the CCN burden, do not play a role in controlling CCN seasonality over the SO. These findings support the central role of biogenic DMS emissions in controlling not only the number but also the variability of CCN over the remote ocean. C1 CSIC, Inst Ciencias Mar, E-08003 Barcelona, Spain. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. RP CSIC, Inst Ciencias Mar, Passeig Maritim Barcelona 37-49, E-08003 Barcelona, Spain. EM sergio.vallina@icm.csic.es RI Gasso, Santiago/H-9571-2014 OI Gasso, Santiago/0000-0002-6872-0018 NR 84 TC 42 Z9 43 U1 1 U2 25 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 MAR 8 PY 2006 VL 20 IS 1 AR GB1014 DI 10.1029/2005GB002597 PG 13 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 025MJ UT WOS:000236270100002 ER PT J AU Marzo, GA Roush, TL Blanco, A Fonti, S Orofino, V AF Marzo, GA Roush, TL Blanco, A Fonti, S Orofino, V TI Cluster analysis of planetary remote sensing spectral data SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID THERMAL EMISSION SPECTROMETER; EARLY MARS; WATER; CLASSIFICATION; SURFACE; MERIDIANI; DEPOSITS; IMAGES; AVHRR AB [1] In this work, an innovative approach for remote sensing data analysis is presented. A statistical multivariate approach, applied to spectroscopic data, is able to reduce and explore the large amount of data collected during planetary missions. The multivariate statistical approach implemented is a cluster analysis method together with a criterium able to identify the natural number of clusters present in the spectral data set. An evaluation of the statistical analysis methods has been developed, implemented, and applied to analyze Mars thermal emission data. We find the statistical approach readily identifies spurious data. The resulting number of clusters provides >= 10(5) reduction in data volume. This allows a focusing of scientific interest onto a limited number of statistically significant groups. A comparison of the results of the statistical approach to previous expert analysis of Mars thermal emission data, for the Sinus Meridiani region where a hematite-rich area of Mars has been previously detected, is provided. We find that several of the clusters reproduce the results of the expert analyses of the Sinus Meridiani hematite distribution. The current approach has the additional advantage of eliminating the time-consuming techniques of atmospheric correction, when surface features are to be investigated. C1 Univ Lecce, Dept Phys, I-73100 Lecce, Italy. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Marzo, GA (reprint author), Univ Lecce, Dept Phys, CP 193, I-73100 Lecce, Italy. EM giuseppe.marzo@le.infn.it RI Marzo, Giuseppe/A-9765-2015 NR 40 TC 13 Z9 13 U1 0 U2 1 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 MAR 8 PY 2006 VL 111 IS E3 AR E03002 DI 10.1029/2005JE002532 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 025MU UT WOS:000236271200001 ER PT J AU Evans, J Stenger, MB Juarez, LA Moore, F Hinghofer-Szalkay, H Ziegler, M Knapp, C AF Evans, J Stenger, MB Juarez, LA Moore, F Hinghofer-Szalkay, H Ziegler, M Knapp, C TI Resting autonomic balance predicts subsequent orthostatic tolerance in women SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Univ Kentucky, Lexington, KY 40506 USA. NASA, Ames Res Ctr, Gravitat Branch, Mountain View, CA 94035 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Med Univ Austria, Graz, Austria. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2006 VL 20 IS 5 BP A1192 EP A1192 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 026GA UT WOS:000236326203204 ER PT J AU Patel, MJ Risin, D Jo, H AF Patel, MJ Risin, D Jo, H TI Gene expression profiles of 2T3 preosteoblasts in microgravity analog systems: Comparison of the random positioning machine and the rotating wall vessel bioreactor SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Georgia Inst Technol, Atlanta, GA 30322 USA. NASA, Johnson Space Ctr, Houston, TX 77058 USA. Emory Univ, Atlanta, GA 30322 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2006 VL 20 IS 5 BP A1250 EP A1250 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 026GA UT WOS:000236326203462 ER PT J AU Platts, SH Shi, SJ Meck, JV AF Platts, SH Shi, SJ Meck, JV TI Midodrine exacerbates promethazine-induced akathisia SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Univ Space Res Assoc, Div Space Life Sci, Houston, TX 77058 USA. Wyle Labs, Houston, TX 77058 USA. NASA, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2006 VL 20 IS 5 BP A1251 EP A1252 PN 2 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 026GA UT WOS:000236326203469 ER PT J AU Tou, J Arnaud, S Brown, M Foley, A Wade, C AF Tou, J Arnaud, S Brown, M Foley, A Wade, C TI Osteopenic changes induced by ovariectomy or combination unloading and ovariectomy in aged rats SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 W Virginia Univ, Morgantown, WV 26506 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Missouri, Columbia, MO 65211 USA. USA, Inst Surg Res, Ft Sam Houston, TX 78234 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2006 VL 20 IS 5 BP A1062 EP A1062 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 026GA UT WOS:000236326202106 ER PT J AU Uchakin, PN Smith, SM Tobin, BW Uchakina, ON AF Uchakin, PN Smith, SM Tobin, BW Uchakina, ON TI Alterations in amino acids metabolism in human immunocytes subjected to microgravity analog SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Mercer Univ, Sch Med, Div Basic Med Sci, Macon, GA 31207 USA. Mercer Univ, Sch Med, Dept Internal Med, Macon, GA 31207 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NF Gamalei Inst Epidemiol & Microbiol, Dept Interferons, Moscow, Russia. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2006 VL 20 IS 5 BP A1055 EP A1056 PN 2 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 026GA UT WOS:000236326202076 ER PT J AU Derimian, Y Karnieli, A Kaufman, YJ Andreae, MO Andreae, TW Dubovik, O Maenhaut, W Koren, I Holben, BN AF Derimian, Y Karnieli, A Kaufman, YJ Andreae, MO Andreae, TW Dubovik, O Maenhaut, W Koren, I Holben, BN TI Dust and pollution aerosols over the Negev desert, Israel: Properties, transport, and radiative effect SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SKY RADIANCE MEASUREMENTS; OPTICAL-PROPERTIES; LIGHT-SCATTERING; SOLAR-RADIATION; AIR-POLLUTION; CLIMATE; PARTICLES; SYSTEM; AERONET; NEPHELOMETER AB [1] The complex spatial, temporal, and optical characteristics of atmospheric aerosols cause large uncertainties in the estimation of aerosol effects on climate. Analysis of long-term measurements from key regions can provide a better understanding of the role of atmospheric aerosols in the climate system. In the current study, observations of aerosol optical properties and mass concentrations were carried out during 1995 - 2003 in the Israeli Negev desert. The measurement site is relatively remote from local pollution sources; however, it lies at the crossroad between dust from the Sahara and the Arabian peninsula and pollution from Europe. The instruments employed were a Sun/sky photometer, a stacked filter unit sampler, and an integrating nephelometer. We analyzed the data for seasonal variability, general vertical aerosol structure, and radiative climate effect by dust and anthropogenic aerosol. The intra-annual variability of aerosol optical properties was found to be closely related to seasonally varying synoptic conditions. Two seasonal peaks of aerosol optical thickness were noted: The first maximum related to dust particle activity and the second to anthropogenic aerosol. Similar maximums were noted in aerosol light scattering at the surface; however, their relative importance is reversed and is related to differences in the vertical distribution of dust and anthropogenic aerosols. The calculated aerosol radiative effect shows cooling both at the top of the atmosphere and at the surface during the whole year. The radiative effect of the airborne dust is the dominating forcing component during most of the time in the study area. C1 Ben Gurion Univ Negev, Jacob Blaustein Inst Desert Res, Remote Sensing Lab, IL-84990 Sede Boqer, Israel. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Max Planck Inst Chem, Biogeochem Dept, D-55020 Mainz, Germany. Univ Ghent, Inst Nucl Sci, Dept Analyt Chem, B-9000 Ghent, Belgium. Weizmann Inst Sci, Dept Environm Sci, IL-76100 Rehovot, Israel. RP Derimian, Y (reprint author), Ben Gurion Univ Negev, Jacob Blaustein Inst Desert Res, Remote Sensing Lab, Sede Boker Campus, IL-84990 Sede Boqer, Israel. EM derimian@bgu.ac.il RI Dubovik, Oleg/A-8235-2009; Koren, Ilan/K-1417-2012; Maenhaut, Willy/M-3091-2013; Andreae, Meinrat/B-1068-2008 OI Dubovik, Oleg/0000-0003-3482-6460; Koren, Ilan/0000-0001-6759-6265; Maenhaut, Willy/0000-0002-4715-4627; Andreae, Meinrat/0000-0003-1968-7925 NR 50 TC 55 Z9 55 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 MAR 7 PY 2006 VL 111 IS D5 AR D05205 DI 10.1029/2005JD006549 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025ML UT WOS:000236270300009 ER PT J AU Strawa, AW Elleman, R Hallar, AG Covert, D Ricci, K Provencal, R Owano, TW Jonsson, HH Schmid, B Luu, AP Bokarius, K Andrews, E AF Strawa, AW Elleman, R Hallar, AG Covert, D Ricci, K Provencal, R Owano, TW Jonsson, HH Schmid, B Luu, AP Bokarius, K Andrews, E TI Comparison of in situ aerosol extinction and scattering coefficient measurements made during the Aerosol Intensive Operating Period SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CAVITY RING-DOWN; LIGHT-ABSORPTION; OPTICAL EXTINCTION; RELATIVE-HUMIDITY; SULFATE AEROSOLS; CLIMATE; CLOUD; NEPHELOMETER; SPECTROSCOPY; CALIBRATION AB [1] In May 2003, the Department of Energy ( DOE) Atmospheric Radiation Measurement ( ARM) Program sponsored the Aerosol Intensive Operating Period (AIOP) which was conducted over the ARM Climate Research Facility (ACRF) in central Oklahoma. One new instrument that flew in the AIOP, called Cadenza, employed a cavity ring-down technique to measure extinction coefficient and a reciprocal nephelometer technique to simultaneously measure scattering coefficient. This instrument is described in this paper, and measurements are compared to those of conventional instrumentation. Agreement between Cadenza extinction coefficient and that derived from combining nephelometer scattering and PSAP absorption (Neph + PSAP) was excellent, about 2%. Agreement between Cadenza scattering coefficient and TSI nephelometer scattering was also excellent, about 2%, well within the uncertainty of the nephelometer and Cadenza scattering measurements. Comparisons between these instruments, made for the special case of plumes, showed that Cadenza measured extinction and scattering several percent higher on average than the Neph + PSAP and nephelometer alone. This difference is likely due to differences in the instrument response time: The response time for Cadenza is 1 s while that for the nephelometer is a minimum of 8 s. Plumes, identified as originating from Siberian biomass burning, are characterized. Composite size distributions from wing-mounted probes showed that two of the plumes had significant large particle modes that resulted in high values of the effective radius. The effect of the large particle mode was not seen in the Angstrom coefficient calculated from the in-cabin scattering measurements because of the characteristics of the aircraft inlet. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. NASA, Ames Res Ctr, Natl Res Council, Moffett Field, CA 94035 USA. Picarro Inc, Sunnyvale, CA USA. Los Gatos Res Inc, Mountain View, CA 94041 USA. USN, Postgrad Sch, Ctr Interdisciplinary Remotely Piloted Aircraft S, Marina Del Rey, CA 93933 USA. Bay Area Environm Res Inst, Sonoma, CA 95476 USA. San Jose State Univ, Dept Comp Sci, San Jose, CA 95192 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80305 USA. RP Strawa, AW (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM astrawa@mail.arc.nasa.gov RI Hallar, Anna Gannet/I-9104-2012 OI Hallar, Anna Gannet/0000-0001-9972-0056 NR 59 TC 23 Z9 23 U1 1 U2 6 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 MAR 7 PY 2006 VL 111 IS D5 AR D05S03 DI 10.1029/2005JD006056 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025ML UT WOS:000236270300004 ER PT J AU Xia, XA Chen, HB Wang, PC Zhang, WX Goloub, P Chatenet, B Eck, TF Holben, BN AF Xia, XA Chen, HB Wang, PC Zhang, WX Goloub, P Chatenet, B Eck, TF Holben, BN TI Variation of column-integrated aerosol properties in a Chinese urban region SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SKY RADIANCE MEASUREMENTS; OPTICAL-PROPERTIES; ANTHROPOGENIC AEROSOLS; AERONET; CLIMATE; VARIABILITY; DEPTH; POLLUTION; NETWORK; ATMOSPHERE AB [1] Thirty-three months of aerosol data in Beijing are presented in this paper. Aerosol optical thickness (AOT) increases from January to June and then decreases gradually. However, airborne particulate matter with diameter less than 10 mu m (PM10) concentration exhibits higher values in winter and spring and lower concentration in summer. For the same PM10 concentration, AOT in summer is approximately two, three, and four times that in autumn, winter, and spring, respectively. AOT increases persistently during daytime, and the diurnal variation varies from about 15% in summer to about 45% in winter. The seasonal and diurnal variation of AOT is quite different from that of surface particle concentration. This is partly attributed to the variation of atmospheric mixing layer height. Aerosol volume concentrations increase with AOT by nearly identical magnitude for fine and coarse mode except in spring. The volume concentration of coarse mode in spring increases by a magnitude of more than two times that derived in remaining seasons. Aerosol fine mode radius increases with AOT, whereas coarse mode radius keeps relatively invariable with AOT. Mean aerosol single-scattering albedo at 440 nm is about 0.90 and decreases slightly with wavelength. Aerosol single-scattering albedos increase and their spectral dependence reverses during dust periods. Aerosol size and absorption in Beijing are close to results derived in Mexico City and Kanpur, but they are quite different from those in Maryland and Paris. Therefore different urban aerosol models should be created and used in satellite remote sensing in different urban regions. C1 Chinese Acad Sci, Inst Atmospher Phys, Beijing 100029, Peoples R China. Univ Lille 1, Opt Atmospher Lab, F-59655 Villeneuve Dascq, France. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. RP Xia, XA (reprint author), Chinese Acad Sci, Inst Atmospher Phys, Beijing 100029, Peoples R China. EM xiaxiangao2000@yahoo.com RI ECK, THOMAS/D-7407-2012; Xia, Xiangao/G-5545-2011 OI Xia, Xiangao/0000-0002-4187-6311 NR 36 TC 77 Z9 85 U1 1 U2 19 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 MAR 7 PY 2006 VL 111 IS D5 AR D05204 DI 10.1029/2005JD006203 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025ML UT WOS:000236270300005 ER PT J AU Kraal, ER Asphaug, E Moore, JM Lorenz, RD AF Kraal, ER Asphaug, E Moore, JM Lorenz, RD TI Quantitative geomorphic modeling of Martian bedrock shorelines SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID GENERAL-CIRCULATION MODEL; ORBITER LASER ALTIMETER; COASTAL GEOMORPHOLOGY; ANCIENT OCEANS; CRATER LAKES; EARLY MARS; WIND; EVOLUTION; SIMULATIONS; PREDICTION AB [1] Multiple researchers have identified shoreline features, such as scarps, on Mars. These features occur in both paleocrater lake basins and the northern hemispheric basin. Here we use a simple numerical model to investigate the viability of forming Martian bedrock scarps via wind wave action. We use the Pierson-Moskowitz equation modified for Martian gravity to generate wave fields under a variety of wind speeds and use those wave fields to drive a terrestrial bedrock shore erosion model modified for Martian conditions. Our results indicate that even with conservative assumptions for the key parameters of wind speed, slope, and substrate, it is difficult to form shoreline features of sufficient magnitude to be captured by spacecraft imaging. Under many combinations of reasonable initial conditions, no shoreline features are formed. In cases where shoreline features do develop, the largest equilibrium scarp height is similar to 5 m, and the shorelines require nearly 2000 model years to form. In light of these results and the difficulty of maintaining warm, wet climates on Mars, it seems unlikely that the putative shoreline features identified in images are a result of water wave erosion, and alternative hypotheses, such as ice cover, should be entertained. C1 Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Univ Arizona, Lunar & Planetary Lab, Dept Planetary Sci, Tucson, AZ 85721 USA. RP Kraal, ER (reprint author), Univ Calif Santa Cruz, Dept Earth Sci, 1156 High St, Santa Cruz, CA 95064 USA. EM ekraal@pmc.ucsc.edu; asphaug@pmc.ucsc.edu; jeff.moore@nasa.gov; rlorenz@lpl.arizona.edu RI Lorenz, Ralph/B-8759-2016 OI Lorenz, Ralph/0000-0001-8528-4644 NR 56 TC 12 Z9 12 U1 0 U2 6 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 MAR 7 PY 2006 VL 111 IS E3 AR E03001 DI 10.1029/2005JE002567 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 025MS UT WOS:000236271000001 ER PT J AU Delozier, DM Watson, KA Smith, JG Clancy, TC Connell, JW AF Delozier, DM Watson, KA Smith, JG Clancy, TC Connell, JW TI Investigation of aromatic/aliphatic polyimides as dispersants for single wall carbon nanotubes SO MACROMOLECULES LA English DT Article ID ELECTROSTATIC CHARGE MITIGATION; POLYMER NANOCOMPOSITE FILMS; ORGANIC POLYMER; FUNCTIONALIZATION; COMPOSITE; SOLUBILIZATION; SONICATION; CHEMISTRY; NAFION AB Novel aromatic/aliphatic polyimides were prepared from 2,7-diamino-9,9'-dioctylfluorene (AFDA) and aromatic dianhydrides. Upon investigating the effectiveness of these polyimides for debundling single wall carbon nanotubes (SWNTs) in solution, three were discovered to aid in the dispersion of SWNTs in N,N-dimethylacetamide (DMAc). Two of these polyimides, one from 3,3',4,4'-oxydiphthalic anhydride (ODPA) and one from symmetric 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), were used to prepare nanocomposites. Homogeneous polyimide/SWNT suspensions from both polymers were used in the preparation of films and fibers containing up to 1 wt % SWNTs. The samples were thermally treated to remove residual solvent, and the films were characterized for SWNT dispersion by optical and high-resolution scanning electron microscopy (HRSEM). Electrical and mechanical properties of the films were also determined. Electrospun fibers were examined by HRSEM to characterize SWNT alignment and orientation. C1 NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. Natl Inst Aerosp, Hampton, VA 23666 USA. RP Connell, JW (reprint author), NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. EM john.w.connell@nasa.gov NR 47 TC 83 Z9 86 U1 1 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD MAR 7 PY 2006 VL 39 IS 5 BP 1731 EP 1739 DI 10.1021/ma051826u PG 9 WC Polymer Science SC Polymer Science GA 018VH UT WOS:000235792400011 ER PT J AU Kala, G Oliver, SAM Kelly, PA Pickens, S Burnett, J Dyer, CB Smith, SM AF Kala, G Oliver, SAM Kelly, PA Pickens, S Burnett, J Dyer, CB Smith, SM TI Fat-soluble vitamin status in self-neglecting elderly SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Enterprise Advisory Serv Inc, Houston, TX 77058 USA. Baylor Coll Med, Quentin Mease Hosp, Consortium Res Elder Self Neglect Texas, CREST, Houston, TX 77004 USA. NASA, Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 6 PY 2006 VL 20 IS 4 BP A127 EP A128 PN 1 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 024OW UT WOS:000236206501060 ER PT J AU Oliver, SAM Kelly, PA Pickens, S Burnett, J Dyer, CB Smith, SM AF Oliver, SAM Kelly, PA Pickens, S Burnett, J Dyer, CB Smith, SM TI Nutritional status in self-neglecting elderly SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Enterprise Advisory Serv Inc, Houston, TX 77058 USA. Baylor Coll Med, Quentin Mease Hosp, Consortium Res Elder Self Neglect Texas, CREST, Houston, TX 77004 USA. NASA, Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 6 PY 2006 VL 20 IS 4 BP A128 EP A128 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 024OW UT WOS:000236206501061 ER PT J AU Parsons-Wingerter, P Chandrasekharan, UM McKay, TL Williams, GL Vickerman, MB Farr, AG Radhakrishnan, K Dicorleto, PE AF Parsons-Wingerter, P Chandrasekharan, UM McKay, TL Williams, GL Vickerman, MB Farr, AG Radhakrishnan, K Dicorleto, PE TI VEGF(165)-dependent switch from increased vessel density to increased vessel diameter and increased endothelial NOS activity SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Cleveland Clin Fdn, Lerner Res Inst, Cleveland, OH 44195 USA. Univ Washington, Sch Med, Seattle, WA 98195 USA. Univ New Mexico, Sch Med, Albuquerque, NM 87131 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 6 PY 2006 VL 20 IS 4 BP A708 EP A709 PN 1 PG 2 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 024OW UT WOS:000236206506019 ER PT J AU Smith, SM Oliver, SAM Dillon, EL Fesperman, JV Zwart, SR AF Smith, SM Oliver, SAM Dillon, EL Fesperman, JV Zwart, SR TI Nutritional status in humans during long-duration bed rest SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Enterprise Advisory Serv Inc, Houston, TX 77058 USA. Univ Space Res Assoc, Houston, TX 77058 USA. RI Dillon, Edgar/B-2495-2008 NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 6 PY 2006 VL 20 IS 4 BP A622 EP A622 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 024OW UT WOS:000236206505161 ER PT J AU Watts, S Zwart, SR Rice, BL Smith, SM AF Watts, S Zwart, SR Rice, BL Smith, SM TI Effects of acid base balance on bone metabolism in bed rest subjects as an analog for space night SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Texas Womans Univ, Houston, TX 77030 USA. Univ Space Res Accoc, Houston, TX 77058 USA. Enterprise Advisory Serv Inc, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 6 PY 2006 VL 20 IS 4 BP A562 EP A562 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 024OW UT WOS:000236206504457 ER PT J AU Zwart, SR Gonda, SR Bolster, DR Smith, SM AF Zwart, SR Gonda, SR Bolster, DR Smith, SM TI Inhibition of NF-[kappa]B activation in osteoclasts by eicosapentaenoic acid SO FASEB JOURNAL LA English DT Meeting Abstract CT Experimental Biology 2006 Meeting CY APR 01-05, 2006 CL San Francisco, CA SP Amer Assoc Anatomists, Amer Physiol Soc, Amer Soc Biochem & Mol Biol, Amer Soc Investigat Pathol, Amer Soc Nutr, Amer Soc Pharmacol & Expt Therapeut C1 Univ Space Res Assoc, Houston, TX 77058 USA. Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 6 PY 2006 VL 20 IS 4 BP A561 EP A561 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 024OW UT WOS:000236206504452 ER PT J AU Frey, HV AF Frey, HV TI Impact constraints on the age and origin of the lowlands of Mars SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CRUSTAL DICHOTOMY; HEMISPHERIC DICHOTOMY; PLATE-TECTONICS; GIANT IMPACT; EVOLUTION; BASIN; TOPOGRAPHY; UTOPIA AB [1]Visible and buried impact basins, seen as "QuasiCircular Depressions'' (QCDs) in MOLA data, provide important new constraints on the age of the Martian lowlands. The buried lowlands are no younger than Early Noachian, at least as old as the oldest exposed (visible) surface units in the highlands. A model absolute age for these buried lowlands is 4.04-4.11 GY (or earlier) but similar model ages for the largest lowland basins are older yet, 4.08-4.18 GY. The lowland crust both formed and became low no later than 500 million years after Mars formed, and likely even earlier. This constrains models for the origin of the fundamental crustal topographic dichotomy on Mars. Mechanisms which operated both early and quickly during the earliest history of Mars ( e. g., large impacts) may be more likely than those requiring extended periods of time (i. e., endogenic models). C1 NASA, Goddard Space Flight Ctr, Planetary Geodynam Lab, Greenbelt, MD 20771 USA. RP Frey, HV (reprint author), NASA, Goddard Space Flight Ctr, Planetary Geodynam Lab, Code 661, Greenbelt, MD 20771 USA. EM herbert.v.frey@nasa.gov NR 31 TC 29 Z9 29 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 MAR 4 PY 2006 VL 33 IS 8 AR L08S02 DI 10.1029/2005GL024484 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 021OY UT WOS:000235993700001 ER PT J AU Christoffersen, P Tulaczyk, S Carsey, FD Behar, AE AF Christoffersen, P Tulaczyk, S Carsey, FD Behar, AE TI A quantitative framework for interpretation of basal ice facies formed by ice accretion over subglacial sediment SO JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE LA English DT Article ID SECONDARY FROST HEAVE; FREEZE-ON MECHANISM; WEST ANTARCTICA; STREAM-C; DEBRIS ENTRAINMENT; TRAPRIDGE GLACIER; ATLANTIC-OCEAN; NORTH-ATLANTIC; POROUS-MEDIUM; GLASS-POWDER AB [1] We have constructed a numerical model of basal ice formation for glacier ice in contact with subglacial sediment. The model predicts four different ice facies whose formation is controlled by availability of subglacial water to satisfy the basal freeze-on rate. Clean ( or clotted) facies may result from congelation ( or frazil) ice growth occurring when ( supercooled) meltwater separates ice base from substrate or if a groundwater source can supply water to the ice base at a velocity equal to the freezing rate. Laminated facies develops when the supply of subglacial water is sufficiently constrained for cryostatic suction to raise the subglacial effective stress above a threshold for intrusion of ice into sediment by regelation. Debris laminas ( similar to 1 mm) are entrained by short, periodic regelation events ( of a few hours) separated by longer periods ( days to months) of congelation. Further meltwater limitation produces a massive dirty ice facies due to stacking of debris laminas. The model predicts growth of solid dirty ice facies when the bed is meltwater-depleted with fast freezing ( 5 mm yr(-1)) causing enhanced erosion ( 30 mm yr(-1)). We find that basal ice facies and sediment entrainment are controlled mainly by the ratio of freezing rate to water supply rate. The predicted ice facies compare favorably with borehole camera imagery of the basal ice layer in Kamb Ice Stream, West Antarctica. Facies variability in this layer suggests complex hydrologic history for the West Antarctic Ice Sheet with significant changes occurring over a period of several thousand years. C1 Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Christoffersen, P (reprint author), Univ Wales, Inst Geog & Earth Sci, Ctr Glaciol, Aberystwyth SY23 3DB, Dyfed, Wales. EM pac@aber.ac.uk RI Christoffersen, Poul/C-7328-2013 OI Christoffersen, Poul/0000-0003-2643-8724 NR 72 TC 19 Z9 19 U1 0 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-EARTH JI J. Geophys. Res.-Earth Surf. PD MAR 4 PY 2006 VL 111 IS F1 AR F01017 DI 10.1029/2005JF000363 PG 12 WC Geosciences, Multidisciplinary SC Geology GA 021PJ UT WOS:000235994800003 ER PT J AU Vinnikov, KY Cavalieri, DJ Parkinson, CL AF Vinnikov, KY Cavalieri, DJ Parkinson, CL TI A model assessment of satellite observed trends in polar sea ice extents SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CLIMATE MODEL; SIMULATION; VARIABILITY AB For more than three decades now, satellite passive microwave observations have been used to monitor polar sea ice. Here we utilize sea ice extent trends determined from satellite data for both the Northern and Southern Hemispheres for the period 1972(73) - 2004, and assess and interpret them using results from simulations by eleven climate models. In the Northern Hemisphere (NH), observations show a statistically significant decrease of sea ice extent and an acceleration of sea ice retreat during the past three decades. However, from the modeled natural variability of sea ice extents in control simulations, we conclude that the acceleration is not statistically significant and should not be extrapolated into the future. Most of the models, like the observations, show an absence of a prominent seasonal cycle in the trend values. Both observations and model simulations show that climate variability in sea ice extent in the Southern Hemisphere (SH) is much larger than in the NH and that the SH sea ice extent trends are not statistically significant. C1 Univ Maryland, Dept Atmospher & Ocean Sci, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Cryospher Sci Branch, Greenbelt, MD 20771 USA. RP Univ Maryland, Dept Atmospher & Ocean Sci, College Pk, MD 20742 USA. EM kostya@atmos.umd.edu RI Vinnikov, Konstantin/F-9348-2010; Parkinson, Claire/E-1747-2012 OI Parkinson, Claire/0000-0001-6730-4197 NR 16 TC 17 Z9 17 U1 0 U2 0 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 MAR 3 PY 2006 VL 33 IS 5 AR L05704 DI 10.1029/2005GL025282 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 021OW UT WOS:000235993500004 ER PT J AU Shen, BW Atlas, R Chern, JD Reale, O Lin, SJ Lee, T Chang, J AF Shen, BW Atlas, R Chern, JD Reale, O Lin, SJ Lee, T Chang, J TI The 0.125 degree finite-volume general circulation model on the NASA Columbia supercomputer: Preliminary simulations of mesoscale vortices SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PAST 3-DIMENSIONAL OBSTACLES; CATALINA EDDY; LEE VORTICES; FLOW AB The NASA Columbia supercomputer was ranked second on the TOP500 List in November, 2004. Such a quantum jump in computing power provides unprecedented opportunities to conduct ultra-high resolution simulations with the finite-volume General Circulation Model (fvGCM). During 2004, the model was run in realtime experimentally at 0.25 degree resolution producing remarkable hurricane forecasts (Atlas et al., 2005). In 2005, the horizontal resolution was further doubled, which makes the fvGCM comparable to the first mesoscale resolving General Circulation Model at the Earth Simulator Center (Ohfuchi et al., 2004). Nine 5-day 0.125 degree simulations of three hurricanes in 2004 are presented first for model validation. Then it is shown how the model can simulate the formation of the Catalina eddies and Hawaiian lee vortices, which are generated by the interaction of the synoptic-scale flow with surface forcing, and have never been reproduced in a GCM before. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, Beltsville, MD USA. NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ USA. NASA, Headquarters, Washington, DC 20546 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Comp Sci Corp, Moffett Field, CA USA. RP Shen, BW (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. EM bo-wen.shen.1@gsfc.nasa.gov RI Atlas, Robert/A-5963-2011 OI Atlas, Robert/0000-0002-0706-3560 NR 12 TC 20 Z9 20 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 MAR 2 PY 2006 VL 33 IS 5 AR L05801 DI 10.1029/2005GL024594 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 021OV UT WOS:000235993400001 ER PT J AU Cede, A Herman, J Richter, A Krotkov, N Burrows, J AF Cede, A Herman, J Richter, A Krotkov, N Burrows, J TI Measurements of nitrogen dioxide total column amounts using a Brewer double spectrophotometer in direct Sun mode SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ABSORPTION CROSS-SECTIONS; SENSING REFERENCE DATA; MAX-DOAS MEASUREMENTS; 231-794 NM RANGE; GOME MEASUREMENTS; STRATOSPHERIC NO2; TROPOSPHERIC NO2; TEMPERATURE; SPECTROSCOPY; SCIAMACHY AB [1] NO2 column amounts were measured for the past 2 years at Goddard Space Flight Center, Greenbelt, Maryland, using a Brewer spectrometer in direct Sun mode. A new "bootstrap'' method to calibrate the instrument is introduced and described. This technique selects the cleanest days from the database to obtain the solar reference spectrum. The main advantage for direct Sun measurements is that the conversion uncertainty from slant column to vertical column is negligible compared to the standard scattered light observations where it is typically on the order of 100% (2 sigma) at polluted sites. The total 2s errors of the direct Sun retrieved column amounts decrease with solar zenith angle and are estimated at 0.2 to 0.6 Dobson units (DU, 1 DU approximate to 2.7 x 10(16) molecules cm(-2)), which is more accurate than scattered light measurements for high NO2 amounts. Measured NO2 column amounts, ranging from 0 to 3 DU with a mean of 0.7 DU, show a pronounced daily course and a strong variability from day to day. The NO2 concentration typically increases from sunrise to noon. In the afternoon it decreases in summer and stays constant in winter. As expected from the anthropogenic nature of its source, NO2 amounts on weekends are significantly reduced. The measurements were compared to satellite retrievals from Scanning Image Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). Satellite data give the same average NO2 column and show a seasonal cycle that is similar to the ground data in the afternoon. We show that NO2 must be considered when retrieving aerosol absorption properties, especially for situations with low aerosol optical depth. C1 Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Bremen, Inst Environm Phys, Bremen, Germany. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Catonsville, MD USA. RP Cede, A (reprint author), Sci Syst & Applicat Inc, Lanham, MD 20706 USA. EM cede@gsfc.nasa.gov RI Richter, Andreas/C-4971-2008; Krotkov, Nickolay/E-1541-2012; Burrows, John/B-6199-2014; OI Richter, Andreas/0000-0003-3339-212X; Krotkov, Nickolay/0000-0001-6170-6750; Burrows, John/0000-0002-6821-5580; Herman, Jay/0000-0002-9146-1632 NR 45 TC 37 Z9 38 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 MAR 2 PY 2006 VL 111 IS D5 AR D05304 DI 10.1029/2005JD006585 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 021PF UT WOS:000235994400004 ER PT J AU Achilleos, N Bertucci, C Russell, CT Hospodarsky, GB Rymer, AM Arridge, CS Burton, ME Dougherty, MK Hendricks, S Smith, EJ Tsurutani, BT AF Achilleos, N Bertucci, C Russell, CT Hospodarsky, GB Rymer, AM Arridge, CS Burton, ME Dougherty, MK Hendricks, S Smith, EJ Tsurutani, BT TI Orientation, location, and velocity of Saturn's bow shock: Initial results from the Cassini spacecraft SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SPECULARLY REFLECTED IONS; SOLAR-WIND; COLLISIONLESS SHOCK; MAGNETIC-FIELD; HIGH-BETA; MAGNETOPAUSE; MAGNETOSPHERE; DYNAMICS; GEOMETRY; FRONT AB [1] The Cassini spacecraft commenced its tour of the planet Saturn on 1 July 2004 ( GMT). During the insertion orbit, the Cassini magnetometer (MAG), radio/plasma wave experiment (RPWS), and plasma spectrometer ( CAPS) obtained in situ measurements of the magnetic field and plasma conditions associated with Saturn's environment. Analysis of the magnetic field data indicate that Cassini repeatedly crossed a mainly quasi-perpendicular bow shock boundary on both the inbound (post-dawn) and outbound (predawn) legs. Modeling of the bow shock and magnetopause crossing positions shows evidence for a magnetospheric compression during Cassini's immersion in the magnetosphere. The magnetic signatures of the bow shock crossings show the clearly defined "overshoot'' and "foot'' regions associated with the quasi-perpendicular geometry. The duration of the shock foot, considered in combination with the RPWS and CAPS solar wind electron parameters upstream of the bow shock crossings, indicates that the length scale for the bow shock ramp at Saturn is about an ion inertial length. This is consistent with multispacecraft observations of the spatial scale of the Earth's shock foot region. The data are generally consistent with Saturn bow shock velocities up to similar to 400 km s(-1) and shock structures governed by ion dynamics. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2AZ, England. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. UCL, Mullard Space Sci Lab, London WC1E 6BT, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Cologne, Inst Geophys & Meteorol, D-50923 Cologne, Germany. RP Achilleos, N (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Prince Consort Rd, London SW7 2AZ, England. EM n.achilleos@imperial.ac.uk RI Achilleos, Nicholas/C-1647-2008; Arridge, Christopher/A-2894-2009; Hendricks, Stefan/D-5168-2011; OI Arridge, Christopher/0000-0002-0431-6526; Hendricks, Stefan/0000-0002-1412-3146; Achilleos, Nicholas/0000-0002-5886-3509; Bertucci, Cesar/0000-0002-2540-5384; Hospodarsky, George/0000-0001-9200-9878 NR 34 TC 32 Z9 32 U1 1 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 MAR 2 PY 2006 VL 111 IS A3 AR A03201 DI 10.1029/2005JA011297 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 021PQ UT WOS:000235995500001 ER PT J AU Skiles, JW AF Skiles, JW TI Plant response to microwaves at 2.45 GHz SO ACTA ASTRONAUTICA LA English DT Article ID FREQUENCY ELECTROMAGNETIC-FIELDS; POWER AB The solar power satellites (SPS) concept envisions an array of satellites in Earth orbit where they will collect solar energy and beam it to Earth. One transmission method is to use microwaves at 2.45 GHz. It is uncertain what the long-term effects will be of continuous microwave energy illumination of the biosphere. An experiment was done that exposed alfalfa to continuous microwave energy at 2.45 GHz with intensities of 0.5-1.2 mW/cm(2). The hypothesis was that plants exposed to microwaves would be no different from those plants not exposed to microwaves. A tray of growing plants was illuminated with microwaves while control plants were grown behind a microwave-opaque shield. Test plants and the control plants were subjected to the same environment otherwise. The experiment was designed so that the only variable to which the test plants were subjected was microwave exposure. Precise, non-destructive measurements were taken weekly of leaf chlorophyll concentration. After 7 weeks the plants were harvested and fresh weight and dry weight were measured. Gross plant variables such as stem length and internodal distance were measured, and overall plant vigor was assessed. In all measured variables there was no difference between the control and the microwave treatment plants. Published by Elsevier Ltd. C1 NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Moffett Field, CA 94035 USA. RP Skiles, JW (reprint author), NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Mail Stop 239-20, Moffett Field, CA 94035 USA. EM Joseph.W.Skiles@nasa.gov NR 15 TC 3 Z9 5 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 MAR PY 2006 VL 58 IS 5 BP 258 EP 263 DI 10.1016/j.actaastro.2005.12.007 PG 6 WC Engineering, Aerospace SC Engineering GA 027LJ UT WOS:000236416800003 ER PT J AU Huntress, W Stetson, D Farquhar, R Zimmerman, J Clark, B O'Neil, W Bourke, R Foing, B AF Huntress, W Stetson, D Farquhar, R Zimmerman, J Clark, B O'Neil, W Bourke, R Foing, B TI The next steps in exploring deep space - A cosmic study by the IAA SO ACTA ASTRONAUTICA LA English DT Article; Proceedings Paper CT 55th International-Astronautical-Federation Congress (IAF) CY 2004 CL Vancouver, CANADA SP Int Astronaut Federat AB This paper presents the results of an IAA cosmic study on the Next Steps in Exploring Deep Space, the goal of which a vision for the scientific exploration of space by humans in the first half of the 21st Century. The study provides a systematic, logical, and science-driven plan for exploration of the Solar System and unlocking the mysteries of program that builds gradually and systematically to establish a permanent presence at each outpost along the way the communications, transportation and other logistical infrastructure as it proceeds. The study suggests a set of Ion goals for space exploration that provide the context for carrying out scientific investigations at specific destinations architecture is derived for the space flight infrastructure required to pursue these science goals at the specified destination examination of the relevant policy and public engagement in this enterprise. (c) 2006 Published by Elsevier Ltd. C1 Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Lockheed Martin Corp, Bethesda, MD 20817 USA. European Space Agcy, F-75738 Paris 15, France. RP Huntress, W (reprint author), Carnegie Inst Washington, Geophys Lab, 5251 Broad Branch Rd NW, Washington, DC 20015 USA. EM w.huntress@gl.ciw.edu; dstetson@jpl.nasa.gov NR 0 TC 6 Z9 7 U1 0 U2 1 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 MAR-APR PY 2006 VL 58 IS 6-7 BP 304 EP 377 DI 10.1016/j.actaastro.2006.01.004 PG 74 WC Engineering, Aerospace SC Engineering GA 026YC UT WOS:000236378400004 ER PT J AU Forsythe, E Achari, A Pusey, ML AF Forsythe, E Achari, A Pusey, ML TI Trace fluorescent labeling for high-throughput crystallography SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID NANOLITRE CRYSTALLIZATION EXPERIMENTS; PROTEIN-CRYSTALLIZATION; ELECTRON-DENSITY; CANAVALIN; INSULIN; SYSTEM; TRIALS; AUTOMATION; LYSOZYME; CRYSTALS AB Covalent labeling of macromolecules with trace levels (< 1%) of a fluorescent dye is proposed as a means to facilitate finding or detecting crystals in crystallization drops. To test the effects of labeled protein concentration on the resulting X-ray diffraction data, experiments were carried out with the model proteins insulin, ribonuclease, lysozyme and thaumatin, which were labeled with the fluorescent dye carboxyrhodamine. All proteins were labeled on their N-terminal amine and lysozyme was also labeled randomly on lysine side chains in a separate series of experiments. Ribonuclease and N-terminal amine-labeled lysozyme crystals were poorly formed at 10% label concentration and these were not used in subsequent diffraction experiments. All model proteins were tested to 5% labeled protein, and thaumatin and randomly labeled lysozyme gave well formed crystals to 10% labeled protein. In all cases tested, the presence of the label was found to not significantly affect the X-ray diffraction data quality obtained. Qualitative visual-inspection experiments over a range of label concentrations indicated that optimum derivatization levels ranged from 0.025 - 0.05% for insulin to 0.1 - 0.25% for thaumatin. Light intensity is a simpler search parameter than straight lines and by virtue of being the most densely packed phase, labeled crystals should be the most intense light sources under fluorescent illumination. For both visual and automated methods of crystal detection, label intensity is a simpler and potentially more powerful search parameter. Screening experiments using the proteins canavalin, beta-lactoglobulins A and B and chymotrypsinogen, all at 0.5% label concentration, demonstrated the utility of this approach to rapidly finding crystals, even when obscured by precipitate. The use of trace-labeled protein is also proposed to be useful for the automated centering of crystals in X-ray beamlines. C1 NASA, George C Marshall Space Flight Ctr, Raytheon IS, Huntsville, AL 35812 USA. Nektar Therapeut, Huntsville, AL 35806 USA. RP Pusey, ML (reprint author), NASA, George C Marshall Space Flight Ctr, Raytheon IS, EM10, Huntsville, AL 35812 USA. EM marc.pusey@msfc.nasa.gov FU NIGMS NIH HHS [GM071581, R21 GM071581] NR 38 TC 37 Z9 39 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD MAR PY 2006 VL 62 BP 339 EP 346 DI 10.1107/S0907444906000813 PN 3 PG 8 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 014LU UT WOS:000235482500013 PM 16510981 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 2 TC 0 Z9 0 U1 0 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 MAR PY 2006 VL 44 IS 3 BP 417 EP 417 DI 10.2514/1.23184 PG 1 WC Engineering, Aerospace SC Engineering GA 021DI UT WOS:000235963300001 ER PT J AU Sodano, HA Bae, JS Inman, DJ Belvin, WK AF Sodano, HA Bae, JS Inman, DJ Belvin, WK TI Modeling and application of eddy current damper for suppression of membrane vibrations SO AIAA JOURNAL LA English DT Article ID MAGNETIC BRAKING; MIRROR AB Inflatable space-based structures have become increasingly popular over the past three decades due to their minimal deployed mass and launch volume. To facilitate packaging of the satellite in the shuttle bay, the optical or antenna surface is in many cases a thin-film membrane. Additionally, because the structure holding the membrane is a lightweight and flexible inflated device, the membrane is subjected to a variety of dynamic loadings. For the satellite to perform optimally, the membrane structure must be free of vibration. However, due to the extreme flexibility of the membrane, the choice of applicable sensing and actuation methods to suppress the vibration is limited. The present study investigates the use of an eddy current damper to passively suppress the vibration of a thin membrane. Eddy currents are induced when a nonmagnetic conductive material is subjected to a time-changing magnetic flux. As the eddy currents circulate inside the conductor they are dissipated, causing energy to be removed from the system and thus allowing the system to function as a type of viscous damper. Using this concept, the ability to generate sufficient damping forces in the extremely thin-film membranes used in space is studied. First, a theoretical model of the interaction between the eddy current damper and the membrane is developed. The model is then validated through experiments carried out at both ambient and vacuum pressures. The results show that the model can accurately predict the damping of the first mode as the distance between the magnet and membrane is varied. Furthermore, the results of the experiments performed oil the membrane at vacuum conditions show the functionality or the damping mechanism in space and indicate damping levels as high as 30% of critical at ambient pressure and 25% of critical at vacuum pressure. C1 Michigan Technol Univ, Houghton, MI 49931 USA. Korea Inst Energy Res, Taejon 305343, South Korea. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Sodano, HA (reprint author), Michigan Technol Univ, Houghton, MI 49931 USA. EM hsodano@mtu.edu; jsbae@kier.re.kr; dinman@vt.edu; w.k.belvin@larc.gov NR 25 TC 9 Z9 9 U1 1 U2 6 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 MAR PY 2006 VL 44 IS 3 BP 541 EP 549 DI 10.2514/1.13024 PG 9 WC Engineering, Aerospace SC Engineering GA 021DI UT WOS:000235963300014 ER PT J AU Helenbrook, BT Atkins, HL AF Helenbrook, BT Atkins, HL TI Application of p-multigrid to discontinuous Galerkin formulations of the Poisson equation SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 17th Computational Fluid Dynamics Conference CY JUN 06-09, 2005 CL Toronto, CANADA SP Amer Inst Aeronaut & Astronaut ID NAVIER-STOKES EQUATIONS; ELEMENT METHOD AB The p-multigrid is investigated as a method for solving discontinuous Galerkin (DG) formulations of the Poisson equation. Different relaxation schemes and basis sets are combined with the DG formulations to find the best performance. The damping factors of the schemes are determined using Fourier analysis for both one- and two-dimensional problems. One important finding is that the standard approach of forming the coarse p matrices separately for each level of multigrid is often unstable. To ensure stability, these matrices must be constructed from the fine grid matrices using algebraic multigrid techniques. Of the relaxation schemes, we find that the combination of Jacobi relaxation with the spectral element basis is fairly effective. The results using this combination are p sensitive in both one and two dimensions, but reasonable convergence rates can still be achieved for moderate values of p and isotropic meshes. A competitive alternative is a block Gauss-Seidel relaxation. This actually outperforms a more expensive line relaxation when the mesh is isotropic. When the mesh becomes highly anisotropic, the implicit line method and the Gauss-Seidel implicit line method are the only effective schemes. Adding the Gauss-Seidel terms to the implicit line method gives a significant improvement over the line relaxation method. C1 Clarkson Univ, Dept Aeronaut & Mech Engn, Potsdam, NY 13699 USA. NASA, Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA. RP Helenbrook, BT (reprint author), Clarkson Univ, Dept Aeronaut & Mech Engn, Potsdam, NY 13699 USA. EM helenbrk@clarkson.edu; h.l.atkins@larc.nasa.gov NR 19 TC 11 Z9 11 U1 0 U2 0 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 MAR PY 2006 VL 44 IS 3 BP 566 EP 575 DI 10.2514/1.15497 PG 10 WC Engineering, Aerospace SC Engineering GA 021DI UT WOS:000235963300017 ER PT J AU Cutler, AD Diskin, GS Drummond, JP White, JA AF Cutler, AD Diskin, GS Drummond, JP White, JA TI Supersonic coaxial jet experiment for computational fluid dynamics code validation SO AIAA JOURNAL LA English DT Article ID LAYERS; FLOW AB An experiment is described that has been conducted to acquire data for the validation of computational fluid dynamics codes used in the design of supersonic combustors. A coaxial nozzle has been designed to produce two uniform, pressure-matched coaxial flows at its exit. The center flow is a 95% He and 5% O-2 mixture at Mach 1.8, and the surrounding flow is air at Mach 1.8. The flow in the resultant supersonic, coaxial jet, which contains compressible mixing layers, is studied. Various methods have been employed in studying the jet flowfield, including schlieren visualization, pilot pressure, total temperature and gas sampling probe, surveys, and RELIEF velocimetry. Boundary conditions and uncertainties are characterized. VULCAN, a structured grid Navier-Stokes code, has been used to calculate the nozzle and jet flowfields, and the results are compared to the experiment. C1 NASA, Langley Res Ctr, Laser & Electroopt Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Hyperson Airbreathing Propuls Branch, Hampton, VA 23681 USA. RP Cutler, AD (reprint author), George Washington Univ, Newport News, VA 23602 USA. NR 28 TC 9 Z9 9 U1 1 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 MAR PY 2006 VL 44 IS 3 BP 585 EP 592 DI 10.2514/1.5781 PG 8 WC Engineering, Aerospace SC Engineering GA 021DI UT WOS:000235963300019 ER PT J AU Hilburger, MW Nemeth, MP Starnes, JH AF Hilburger, MW Nemeth, MP Starnes, JH TI Shell buckling design criteria based on manufacturing imperfection signatures SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 44th Structures, Structural Dynamics and Materials Conference CY APR 07-10, 2003 CL Norfolk, VA SP AIAA, ASME, ASCE, AHS, ASC ID SHUTTLE SUPERLIGHTWEIGHT TANK; LIQUID-OXYGEN TANK; NONLINEAR BEHAVIOR; GEOMETRIC IMPERFECTIONS; LOADS AB An analysis-based approach for developing shell-buckling design criteria for laminated-composite cylindrical shells that accurately account for the effects of initial geometric imperfections is presented. With this approach, measured initial geometric imperfection data from six graphite-epoxy shells are used to determine a manufacturing process-specific imperfection signature for these shells. This imperfection signature is then used as input into nonlinear finite element analyses. The imperfection signature represents a first-approximation mean imperfection shape that is suitable for developing preliminary-design data. Comparisons of test data and analytical results obtained by using several different imperfection shapes are presented for selected shells. These shapes include the actual measured imperfection shape of the test specimens, a first-approximation mean imperfection shape, with and without plus or minus one standard deviation, and the linear-bifurcation-mode imperfection shape. In addition, buckling interaction curves for composite shells subjected to combined axial compression and torsion loading are presented that were obtained by using the various imperfection shapes in the analyses. A discussion of the nonlinear finite element analyses is also presented. Overall, the results indicate that the analysis-based approach presented for developing reliable preliminary-design criteria has the potential to provide improved, less conservative buckling-load estimates and to reduce the weight and cost of developing buckling-resistant shell structures. C1 NASA, Langley Res Ctr, Mech Struct & Mat Branch, Hampton, VA 23681 USA. RP Hilburger, MW (reprint author), NASA, Langley Res Ctr, Mech Struct & Mat Branch, Hampton, VA 23681 USA. NR 38 TC 22 Z9 23 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 MAR PY 2006 VL 44 IS 3 BP 654 EP 663 DI 10.2514/1.5429 PG 10 WC Engineering, Aerospace SC Engineering GA 021DI UT WOS:000235963300027 ER PT J AU Parsons-Wingerter, P McKay, TL Leontiev, D Vickerman, MB Condrich, TK Dicorleto, PE AF Parsons-Wingerter, P McKay, TL Leontiev, D Vickerman, MB Condrich, TK Dicorleto, PE TI Lymphangiogenesis by blind-ended vessel sprouting is concurrent with hemangiogenesis by vascular splitting SO ANATOMICAL RECORD PART A-DISCOVERIES IN MOLECULAR CELLULAR AND EVOLUTIONARY BIOLOGY LA English DT Article DE lymphangiogenesis; hemangiogenesis; sprouting; splitting; vascular endothelial growth factor; vascular; lymphatic; Euclidean distance map; chorioallantoic membrane; quail; avian ID ENDOTHELIAL GROWTH-FACTOR; CHICK CHORIOALLANTOIC MEMBRANE; ANGIOGENESIS IN-VIVO; LYMPHATIC-SYSTEM; FRACTAL ANALYSIS; VEGF-C; VASCULOGENESIS; FIBROBLAST; ORIGIN; CELLS AB Development of effective vascular therapies requires the understanding of all modes of vessel formation involved in angiogenesis (here termed "hemangiogenesis") and lymphangiogenesis. Two major modes of vessel morphogenesis include sprouting of a new vessel from a preexisting vessel and splitting of a preexisting parent vessel into two offspring vessels. In the quail chorioallantoic membrane (CAM) during mid-development (embryonic days E6-E9), lymphangiogenesis progressed primarily via blind-ended vessel sprouting. Isolated lymphatic endothelial progenitor cells were recruited to the tips of growing vessels. During concurrent hemangiogenesis, parent blood vessels expanded from the capillary network and split into offspring vessels, accompanied by transient capillary expression of alpha smooth muscle actin (alpha SMA) and recruitment of polarized mural progenitor cells. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptor VEGFR-2, aSMA (specific to CAM blood vessels), homeobox transcription factor Prox1 (specific to lymphatics), and the quail hematopoetic marker, QH-1. VEGFR-2 was expressed intensely in isolated cells and lymphatics, and moderately in blood vessels. Prox1 was absent from isolated progenitor cells prior to lymphatic recruitment. Exogenous vascular endothelial growth factor-165 (VEGF(165)) increased blood vessel density and anastomotic frequency without changing endogenous modes of vascular/lyinphatic vessel formation or marker expression. Although VEGF(165) is a key cellular regulator of hemangiogenesis and vasculogenesis, the role of VEGF(165) in lymphangiogenesis is less clear. Interestingly, VEGF(165) increased lymphatic vessel diameter and density as measured by novel Euclidean distance mapping, and the antimaturational dissociation of lymphatics from blood vessels, accompanied by lymphatic reassociation into homogeneous networks. Published 2006 Wiley-Liss, Inc. C1 NASA, Glenn Res Ctr, Micrograv Sci Div, Res & Technol Directorate, Cleveland, OH 44135 USA. Cleveland Clin Fdn, Lerner Res Inst, Dept Cell Biol, Cleveland, OH 44195 USA. NASA, Glenn Res Ctr, Natl Ctr Space Explorat Res, Cleveland, OH 44135 USA. Cleveland Clin Fdn, Lerner Res Inst, Imaging Core Facil, Cleveland, OH 44195 USA. NASA, Glenn Res Ctr, Div Comp Sci, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, RS Informat Syst Inc, Cleveland, OH 44135 USA. RP Parsons-Wingerter, P (reprint author), NASA, Glenn Res Ctr, Micrograv Sci Div, Res & Technol Directorate, MS 110-3, Cleveland, OH 44135 USA. EM patricia.parsons@grc.nasa.gov NR 57 TC 13 Z9 14 U1 1 U2 2 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 1552-4884 J9 ANAT REC PART A JI Anat. Rec. Part A PD MAR PY 2006 VL 288A IS 3 BP 233 EP 247 DI 10.1002/ar.a.20309 PG 15 WC Anatomy & Morphology SC Anatomy & Morphology GA 024SO UT WOS:000236216600003 PM 16489601 ER PT J AU Craven, M Carsey, F Nicol, S AF Craven, M Carsey, F Nicol, S TI Short note - Ice krill under the Amery Ice Shelf, East Antarctica SO ANTARCTIC SCIENCE LA English DT Article ID EUPHAUSIA-CRYSTALLOROPHIAS; LIFE C1 Australian Antarctic Div, Hobart, Tas 7050, Australia. CRC, Antarctic Climate & Ecosyst, Hobart, Tas 7001, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Craven, M (reprint author), Australian Antarctic Div, Channel Highway, Hobart, Tas 7050, Australia. NR 17 TC 3 Z9 4 U1 1 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA SN 0954-1020 J9 ANTARCT SCI JI Antarct. Sci. PD MAR PY 2006 VL 18 IS 1 BP 81 EP 82 DI 10.1017/S095410206000071 PG 2 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 020QA UT WOS:000235923600008 ER PT J AU Gaya-Pique, LR Ravat, D De Santis, A Torta, JM AF Gaya-Pique, LR Ravat, D De Santis, A Torta, JM TI New model alternatives for improving the representation of the core magnetic field of Antarctica SO ANTARCTIC SCIENCE LA English DT Article DE geomagnetic secular variation; IGRF; magnetic anomalies; spherical harmonics ID GEOMAGNETIC REFERENCE FIELD; AEROMAGNETIC ANOMALIES AB Use of the International Geomagnetic Reference Field Model (IGRF) to construct magnetic anomaly maps can lead to problems with the accurate determination of magnetic anomalies that are readily apparent at the edges of local or regional magnetic surveys carried out at different epochs. The situation is severe in areas like Antarctica, where ionospheric activity is intense and only a few ground magnetic observatories exist. This makes it difficult to properly separate from ionospheric variations the secular variation of the core magnetic field. We examine two alternatives to the piecewise-continuous IGRF core magnetic field in Antarctica for the last 45 years: the present global Comprehensive Model (CM4) and the new version of the Antarctic Reference Model (ARM). Both these continuous models are better at representing the secular variation in Antarctica than the IGRF. Therefore, their use is recommended for defining the crustal magnetic field of Antarctica (e.g. the next generation of the Antarctic Digital Magnetic Anomaly Map). C1 Ist Nazl Geofis & Vulcanol, I-00143 Rome, Italy. URL, CSIC, Observ Ebre, Roquetes 43520, Spain. So Illinois Univ, Dept Geol, Carbondale, IL 62901 USA. RP Gaya-Pique, LR (reprint author), NASA, Goddard Space Flight Ctr, UMBC, GEST, Code 698, Greenbelt, MD 20771 USA. EM gaya@geomag.gsfc.nasa.gov RI Torta, Joan Miquel/C-7614-2014; OI Torta, Joan Miquel/0000-0002-4340-7308; Ravat, Dhananjay/0000-0003-1962-4422 NR 29 TC 9 Z9 9 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0954-1020 J9 ANTARCT SCI JI Antarct. Sci. PD MAR PY 2006 VL 18 IS 1 BP 101 EP 109 DI 10.1017/S0954102006000095 PG 9 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 020QA UT WOS:000235923600010 ER PT J AU Egami, E Neugebauer, G Soifer, BT Matthews, K Becklin, EE Ressler, ME AF Egami, E Neugebauer, G Soifer, BT Matthews, K Becklin, EE Ressler, ME TI Subarcsecond mid-infrared observations of NGC 6240: Limitations of active galactic nucleus-starburst power diagnostics SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (NGC 6240); galaxies : interactions; galaxies : nuclei; galaxies : starburst; infrared : galaxies ID ULTRALUMINOUS INFRARED GALAXIES; X-RAY-EMISSION; MICRON LINE DEFICIT; NGC 6240; LUMINOUS GALAXIES; MOLECULAR-HYDROGEN; INTERACTING GALAXY; ADAPTIVE OPTICS; STAR-FORMATION; ARP 220 AB In order to examine the relative importance of powerful starbursts and Compton-thick active galactic nuclei (AGNs) in NGC 6240, we have obtained mid-infrared images and low-resolution spectra of the galaxy with subarcsecond spatial resolution using the Keck telescopes. Despite the high spatial resolution (similar to 200 pc) of our data, no signature of the hidden AGNs has been detected in the mid-infrared. The southern nucleus, which we show provides 80%-90% of the total 8-25 mu m luminosity of the system, has a mid-infrared spectrum and a mid-/far-infrared spectral energy distribution consistent with starbursts. At the same time, however, it is also possible to attribute up to 60% of the bolometric luminosity to an AGN, consistent with X-ray observations, if the AGN is heavily obscured and emits mostly in the far-infrared. This ambiguity arises because the intrinsic variation of properties among a given galaxy population (e.g., starbursts) introduces at least a factor of a few uncertainty even into the most robust AGN-starburst diagnostics. We conclude that with present observations it is not possible to determine the dominant power source in galaxies when AGN and starburst luminosities are within a factor of a few of each other. C1 CALTECH, Caltech Opt Observ, Pasadena, CA 91125 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Egami, E (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. NR 70 TC 12 Z9 12 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 MAR PY 2006 VL 131 IS 3 BP 1253 EP 1261 DI 10.1086/499524 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RK UT WOS:000236143700006 ER PT J AU Cushing, MC Vacca, WD AF Cushing, MC Vacca, WD TI The schizophrenic spectrum of LSR 1610-0040: A peculiar M dwarf/subdwarf SO ASTRONOMICAL JOURNAL LA English DT Article DE infrared : stars; stars : individual (LHS 3409, LHS 1135, LSR 2036+5059, LSR 1610-0040); stars : late-type; stars : low-mass, brown dwarfs; subdwarfs ID HIGH PROPER MOTION; NEAR-INFRARED SPECTRA; ALL-SKY SURVEY; M-DWARFS; ULTRACOOL SUBDWARF; NORTHERN STARS; BROWN DWARF; T-DWARFS; MICRON; ATMOSPHERES AB We present a moderate-resolution (R equivalent to lambda/Delta lambda approximate to 2000), 0.8-4.1 mu m spectrum of LSR 1610-0040, a high proper motion star classified as an early-type L subdwarf by Lepine and collaborators based on its red-optical spectrum. The near-infrared spectrum of LSR 1610-0040 does not fit into the (tentative) M/L subdwarf sequence but rather exhibits a mix of characteristics found in the spectra of both M dwarfs and M subdwarfs. In particular, the near-infrared spectrum exhibits an Na I doublet and CO overtone band heads in the K band and Al I and K I lines and an FeH band head in the H band, all of which have strengths more typical of field M dwarfs. Furthermore, the spectrum of Gl 406 (M6 V) provides a reasonably good match to the 0.6-4.1 m spectral energy distribution of LSR 1610-0040. Nevertheless, the near-infrared spectrum of LSR 1610-0040 also exhibits features common to the spectra of M subdwarfs, including a strong Ti I multiplet centered at similar to 0.97 mu m, a weak VO band at similar to 1.06 mu m, and possible collision-induced H(2) absorption in the H and K bands. We discuss a number of possible explanations for the appearance of the red-optical and near-infrared spectra of LSR 1610-0040. Although we are unable to definitively classify LSR 1610-0040, the preponderance of evidence suggests that it is a mildly metal-poor M dwarf. Finally, we tentatively identify a new band of TiO at similar to 0.93 mu m in the spectra of M dwarfs. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. NASA, Ames Res Ctr, USRA, SOFIA, Moffett Field, CA 94035 USA. RP Cushing, MC (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM mcushing@as.arizona.edu; wvacca@mail.arc.nasa.gov NR 36 TC 20 Z9 20 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 MAR PY 2006 VL 131 IS 3 BP 1797 EP 1805 DI 10.1086/499583 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RK UT WOS:000236143700048 ER PT J AU Draper, DW Elias, NM Noecker, MC Dumont, PJ Lay, OP Ware, B AF Draper, DW Elias, NM Noecker, MC Dumont, PJ Lay, OP Ware, B TI Planet signal extraction for the Terrestrial Planet Finder interferometer SO ASTRONOMICAL JOURNAL LA English DT Article DE methods : data analysis; planetary systems; techniques : high angular resolution; techniques : image processing; techniques : interferometric AB Signal extraction is a vital link between science and systems-engineering requirements. In this paper we present a Terrestrial Planet Finder (TPF) interferometer planet-signal-extraction algorithm and demonstrate the performance of several nulling-interferometer designs on canonical TPF astronomical scenes. We create the output response of a linear phase-chopping dual Bracewell nulling interferometer and a matrix version of the correlation method employed to generate dirty images. We derive general and specific map parameters, such as signal-to-noise ratio, signal-to-artifact ratio, and detection confidence, used for individual maps or comparing array architectures. We implement a matrix form of CLEAN that removes map artifacts, produces reconstructed images, and retrieves planetary signals. Monte Carlo simulations show that some fixed-length structurally connected interferometer configurations can detect Earth-like planets for systems at 10 pc in the presence of stellar Poisson noise. Since angular resolution depends on baseline length, a design that can vary array configuration for each specific scene is superior to an interferometer with a fixed array length. Thus, a flexible free-flying architecture should satisfy the science requirements for more TPF candidates, compared to a fixed-length structurally connected architecture. C1 Ball Aerosp & Technol Corp, Boulder, CO 80306 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Draper, DW (reprint author), Ball Aerosp & Technol Corp, POB 1062, Boulder, CO 80306 USA. EM ddraper@ball.com NR 11 TC 7 Z9 7 U1 0 U2 2 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 MAR PY 2006 VL 131 IS 3 BP 1822 EP 1836 DI 10.1086/499528 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RK UT WOS:000236143700051 ER PT J AU Delsanti, A Peixinho, N Boehnhardt, H Barucci, A Merlin, F Doressoundiram, A Davies, JK AF Delsanti, A Peixinho, N Boehnhardt, H Barucci, A Merlin, F Doressoundiram, A Davies, JK TI Near-infrared color properties of Kuiper Belt objects and Centaurs: Final results from the ESO large program SO ASTRONOMICAL JOURNAL LA English DT Article DE infrared : solar system; Kuiper Belt; methods : statistical; techniques : photometric ID TRANS-NEPTUNIAN OBJECTS; WATER ICE; SPECTROPHOTOMETRIC OBSERVATIONS; TRANSNEPTUNIAN OBJECTS; VISIBLE PHOTOMETRY; SURFACE MATERIALS; SOLAR-SYSTEM; 5145 PHOLUS; 1997 CU26; TNOS AB We present near-IR JHK broadband photometry for 17 Kuiper Belt objects (KBOs) and Centaurs. The observations were performed within the ESO Large Program on the "Physical Properties of Kuiper Belt Objects and Centaurs'' from 2001 January to 2002 August. We used the ISAAC instrument at the ESO 8 m Very Large Telescope. We compiled visible-near-IR colors for a total of 51 published objects and performed a statistical analysis. Color-color correlations show that the same coloring process is probably acting on Centaur and KBO surfaces in the visible near-IR range. Centaurs with H-K smaller than the Sun (0.06) systematically display the reddest B-V colors (at the 2.5 sigma level). These Centaur surfaces are suspected of harboring material that has spectral signatures around 1.7-2.2 mu m (water ice is a possibility; it was reported for the three objects that have published spectroscopy). We report no statistically significant evidence for a bimodal structure of the VJHK Centaur colors (Kolmogorov-Smirnov and dip tests on up to 17 objects). The Centaur H-K colors show some robust evidence (significance level > 99.99%) for a continuous structure. We also report a statistically significant bimodal structure of the Centaur B-R distribution, which is compatible with the results published by Peixinho et al. in 2003 with different data. Classical KBOs show no trends at the 3 sigma level. The V-J color is marginally correlated with perihelion distance q (which is consistent with results reported by Doressoundiram et al. in 2005 on B-R colors). Resonant and scattered disk objects are under-represented ( seven and nine objects, respectively) and show no statistically significant trend. Some of the marginal trends are mentioned as worthy of subsequent monitoring. C1 Astron Inst, Honolulu, HI 96822 USA. NASA, Astrobiol Inst, Honolulu, HI 96822 USA. Univ Lisbon, Ctr Astron & Astrofis, Observ Astron Lisboa, PT-1349018 Lisbon, Portugal. Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany. Observ Paris, LESIA, F-92195 Meudon, France. Royal Observ, Astron Technol Ctr, Edinburgh EH9 3HJ, Midlothian, Scotland. RP Delsanti, A (reprint author), Astron Inst, 2680 Woodlawn Dr, Honolulu, HI 96822 USA. EM delsanti@ifa.hawaii.edu; peixinho@oal.ul.pt; boehnhardt@linmpi.mpg.de; antonella.barucci@obspm.fr; frederic.merlin@obspm.fr; alain.doressoundiram@obspm.fr; jkd@roe.ac.uk RI Peixinho, Nuno/B-2570-2014 OI Peixinho, Nuno/0000-0002-6830-476X NR 62 TC 23 Z9 23 U1 1 U2 2 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 MAR PY 2006 VL 131 IS 3 BP 1851 EP 1863 DI 10.1086/499402 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RK UT WOS:000236143700053 ER PT J AU Petrov, L Kovalev, YY Fomalont, EB Gordon, D AF Petrov, L Kovalev, YY Fomalont, EB Gordon, D TI The fourth VLBA calibrator survey: VCS4 SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; catalogs; surveys ID CELESTIAL REFERENCE FRAME; ACTIVE GALACTIC NUCLEI; QUASARS; SYSTEM AB This paper presents the fourth extension to the VLBA Calibrator Survey, containing 258 new sources not previously observed with very long baseline interferometry (VLBI). This survey, based on three 24 hr Very Long Baseline Array observing sessions, fills remaining areas on the sky above declination -40 degrees where the calibrator density is less than one source within a 4 degrees radius disk in any given direction. The share of these areas was reduced from 4.6% to 1.9%. Source positions were derived from astrometric analysis of group delays determined at 2.3 and 8.6 GHz frequency bands using the Calc/Solve software package. The VCS4 catalog of source positions, plots of correlated flux density versus projected baseline length, contour plots, and fits files of naturally weighted CLEAN images, as well as calibrated visibility function files, are available online and can be found using the search keyword "VCS4.'' C1 NVI Inc, Greenbelt, MD 20770 USA. Natl Radio Astron Observ, Green Bank, WV 24944 USA. Ctr Astro Space, PN Lebedev Phys Inst, Moscow 117997, Russia. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. NASA, Goddard Space Flight Ctr, Raytheon, Greenbelt, MD 20771 USA. RP Petrov, L (reprint author), NVI Inc, 7257 Hanover Pkwy,Suite D, Greenbelt, MD 20770 USA. EM leonid.petrov@lpetrov.net; ykovalev@nrao.edu; efomalon@nrao.edu; dgg@leo.gsfc.nasa.gov RI Kovalev, Yuri/J-5671-2013 OI Kovalev, Yuri/0000-0001-9303-3263 NR 21 TC 71 Z9 72 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 MAR PY 2006 VL 131 IS 3 BP 1872 EP 1879 DI 10.1086/499947 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 023RK UT WOS:000236143700055 ER PT J AU Bertram, T Eckart, A Krips, M Staguhn, JG Hackenberg, W AF Bertram, T Eckart, A Krips, M Staguhn, JG Hackenberg, W TI Molecular gas in the galaxy cluster Abell 262 - CO observations of UGC 1347 and other galaxies of the cluster SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : clusters : individual : Abell 262; galaxies : evolution; ISM : molecules; galaxies : individual : UGC 1347 ID SPIRAL GALAXIES; VIRGO CLUSTER; VELOCITY DISPERSIONS; NEUTRAL HYDROGEN; NEARBY CLUSTERS; STAR-FORMATION; RICH CLUSTERS; DEFICIENCY; SUPERCLUSTER; TELESCOPE AB We present millimeter CO line emission observations of 12 galaxies within the Abell 262 cluster, together with L-FIR data, in the context of a possible molecular gas deficiency within the region of the cluster center. Several indications of the presence of such a deficiency are highlighted and connected to a model of cirrus-like cloud stripping. The model predicts a drop in the average 100 mu m flux density of galaxies in the core of the cluster compared to the average 100 mu m flux density in the outer regions, which is actually indicated in the IRAS data of the cluster members. This drop is explained by the decrease in the total hydrogen column density N(H) and, therefore, also includes a decrease in the molecular gas content. In addition to results for the global CO content of the galaxy sample, high-resolution interferometric CO(1-0) observations of one of the cluster members, UGC 1347, exemplify the spatial distribution of the molecular gas in a galaxy of the cluster. With these observations, it was possible to confirm the existence of a bright off-nuclear CO-emission source and to derive molecular masses and line ratios for this source and the nucleus. C1 Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. European So Observ, D-85748 Garching, Germany. RP Bertram, T (reprint author), Univ Cologne, Inst Phys 1, Zulpicher Str 77, D-50937 Cologne, Germany. EM bertram@ph1.uni-koeln.de NR 46 TC 2 Z9 2 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 MAR PY 2006 VL 448 IS 1 BP 29 EP 42 DI 10.1051/0004-6361:20042564 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018PP UT WOS:000235777600005 ER PT J AU Ehrenreich, D Tinetti, G des Etangs, AL Vidal-Madjar, A Selsis, F AF Ehrenreich, D Tinetti, G des Etangs, AL Vidal-Madjar, A Selsis, F TI The transmission spectrum of Earth-size transiting planets SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE planets and satellites : general ID RAYLEIGH-SCATTERING; EXTRASOLAR PLANETS; ATMOSPHERES; SEARCH; STARS; LIGHT; WATER; LIFE AB A variety of terrestrial planets with different physical parameters and exotic atmospheres might plausibly exist outside our Solar System, waiting to be detected by the next generation of space-exploration missions. Some of these planets might be transiting their parent star. We present here a detailed study of the atmospheric signatures of transiting Earth-size exoplanets. We focus on a limited number of significant examples, for which we discuss the detectability of some of the possible molecules present in their atmospheres, such as water (H2O), carbon dioxide (CO2), ozone (O-3), or molecular oxygen (O-2). To this purpose, we developed a model to simulate transmission spectra of Earth-size exoplanets from the ultraviolet (UV) to the near infrared (NIR). According to our calculations, the signatures of planetary atmospheres represent an absorption of a few parts-per-million (ppm) in the stellar flux. The atmospheres of a few Earth-like planets can be detected with a 30-40 m telescope. The detection of the extensive atmospheres of tens of small satellites of giant exoplanets and hundreds of hypothetical ocean-planets can be achieved with 20-30 m and 10-20 m instruments, respectively, provided all these planets are frequent and they are efficiently surveyed. We also found that planets around K stars are favored, mainly because these stars are more numerous and smaller compared to G or F stars. While not addressed in this study, limitations might come from stellar photometric micro-variability. C1 Univ Paris 06, Inst Astrophys Paris, CNRS, UMR 7095, F-75014 Paris, France. CALTECH, NASA, Astrobiol Inst, IPAC, Pasadena, CA 91125 USA. Ecole Normale Super Lyon, Ctr Rech Astron Lyon, F-69364 Lyon, France. RP Ehrenreich, D (reprint author), Univ Paris 06, Inst Astrophys Paris, CNRS, UMR 7095, 98bis Blvd Arago, F-75014 Paris, France. EM ehrenreich@iap.fr OI Ehrenreich, David/0000-0001-9704-5405; Tinetti, Giovanna/0000-0001-6058-6654 NR 47 TC 63 Z9 64 U1 0 U2 8 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 MAR PY 2006 VL 448 IS 1 BP 379 EP 393 DI 10.1051/0004-6361:20053861 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018PP UT WOS:000235777600036 ER PT J AU Knapen, JH Mazzuca, LM Boker, T Shlosman, I Colina, L Combes, F Axon, DJ AF Knapen, JH Mazzuca, LM Boker, T Shlosman, I Colina, L Combes, F Axon, DJ TI Massive star formation in the central regions of spiral galaxies SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : spiral; galaxies : structure; galaxies : nuclei ID DISK GALAXIES; BAND OBSERVATIONS; SEYFERT-GALAXIES; GALACTIC NUCLEI; NGC-7217; BARS; STRENGTHS; NEARBY; SAMPLE; RINGS AB Context. The morphology of massive star formation in the central regions of galaxies is an important tracer of the dynamical processes that govern the evolution of disk, bulge, and nuclear activity. Aims. We present optical imaging of the central regions of a sample of 73 spiral galaxies in the H alpha line and in optical broad bands, and derive information on the morphology of massive star formation. Methods. We obtained images with the William Herschel Telescope, mostly at a spatial resolution of below one second of arc. For most galaxies, no H alpha imaging is available in the literature. We outline the observing and data reduction procedures, list basic properties, and present the I-band and continuum-subtracted H alpha images. We classify the morphology of the nuclear and circumnuclear H alpha emission and explore trends with host galaxy parameters. Results. We confirm that late-type galaxies have a patchy circumnuclear appearance in H alpha, and that nuclear rings occur primarily in spiral types Sa-Sbc. We identify a number of previously unknown nuclear rings, and confirm that nuclear rings are predominantly hosted by barred galaxies. Conclusions. Other than in stimulating nuclear rings, bars do not influence the relative strength of the nuclear H alpha peak, nor the circumnuclear H alpha morphology. Even considering that our selection criteria led to an over-abundance of galaxies with close massive companions, we do not find any significant influence of the presence or absence of a close companion on the relative strength of the nuclear H alpha peak, nor on the H alpha morphology around the nucleus. C1 Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. European Space Agcy, Estec, NL-2200 AG Noordwijk, Netherlands. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. CSIC, Inst Estructura Mat, E-28006 Madrid, Spain. Observ Paris, F-75014 Paris, France. Rochester Inst Technol, Dept Phys, Rochester, NY 14623 USA. RP Knapen, JH (reprint author), Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. EM j.knapen@star.herts.ac.uk OI Combes, Francoise/0000-0003-2658-7893 NR 43 TC 41 Z9 41 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 MAR PY 2006 VL 448 IS 2 BP 489 EP U44 DI 10.1051/0004-6361:20053928 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018PQ UT WOS:000235777700017 ER PT J AU Moretti, A Perri, M Capalbi, M Angelini, L Hill, JE Campana, S Burrows, DN Osborne, JP Tagliaferri, G Cusumano, G Giommi, P Romano, P Mineo, T Kennea, J Morris, D Nousek, J Pagani, C Racusin, J Abbey, AF Beardmore, AP Godet, O Goad, MR Page, KL Wells, AA Chincarini, G AF Moretti, A Perri, M Capalbi, M Angelini, L Hill, JE Campana, S Burrows, DN Osborne, JP Tagliaferri, G Cusumano, G Giommi, P Romano, P Mineo, T Kennea, J Morris, D Nousek, J Pagani, C Racusin, J Abbey, AF Beardmore, AP Godet, O Goad, MR Page, KL Wells, AA Chincarini, G TI A refined position catalogue of the Swift XRT afterglows SO ASTRONOMY & ASTROPHYSICS LA English DT Article ID X-RAY TELESCOPE; MISSION AB We present a catalogue of refined positions of 68 gamma ray burst (GRB) afterglows observed by the Swift X-ray Telescope (XRT) from the launch up to 2005 Oct. 16. This is a result of the refinement of the XRT boresight calibration. We tested this correction by means of a systematic study of a large sample of X-ray sources observed by XRT with well established optical counterparts. We found that we can reduce the systematic error radius of the measurements by a factor of two, from 6.5 '' to 3.2 '' (90% of confidence). We corrected all the positions of the afterglows observed by XRT in the first 11 months of the Swift mission. This is particularly important for the 37 X-ray afterglows without optical counterpart. Optical follow-up of dark GRBs, in fact, will be more efficient with the use of the more accurate XRT positions. C1 Osserv Astron Brera, INAF, I-23807 Merate, LC, Italy. ASI Sci Data Ctr, I-00044 Frascati, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Leicester, Dept Phys & Astron, Xray Observat Astron Grp, Leicester LE1 7RH, Leics, England. Inst Astrofis Spaziale & Fis Cosmica Sez Palermo, INAF, I-90146 Palermo, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. RP Moretti, A (reprint author), Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy. EM moretti@merate.mi.astro.it RI Racusin, Judith/D-2935-2012; OI Mineo, Teresa/0000-0002-4931-8445; Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Perri, Matteo/0000-0003-3613-4409; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 13 TC 37 Z9 37 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 MAR PY 2006 VL 448 IS 2 BP L9 EP U13 DI 10.1051/0004-6361:200600007 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018PQ UT WOS:000235777700002 ER PT J AU Cox, NLJ Cordiner, MA Cami, J Foing, BH Sarre, PJ Kaper, L Ehrenfreund, P AF Cox, NLJ Cordiner, MA Cami, J Foing, BH Sarre, PJ Kaper, L Ehrenfreund, P TI The Large Magellanic Cloud: diffuse interstellar bands, atomic lines and the local environmental conditions SO ASTRONOMY & ASTROPHYSICS LA English DT Review DE astrochemistry; Magellanic clouds; ISM : clouds; ISM : lines and bands; ISM : abundances ID HIGH-RESOLUTION OBSERVATIONS; INTERNATIONAL-ULTRAVIOLET-EXPLORER; POLYCYCLIC AROMATIC-HYDROCARBONS; CA-II ABSORPTION; WOLF-RAYET STARS; INTER-STELLAR; NA-I; 30 DORADUS; FAR-ULTRAVIOLET; SPECTRAL CLASSIFICATION AB The Large Magellanic Cloud (LMC) offers a unique laboratory to study the diffuse interstellar bands (DIBs) under conditions that are profoundly different from those in the Galaxy. DIB carrier abundances depend on several environmental factors, in particular the local UV radiation field. In this paper we present measurements of twelve DIBs in five lines of sight to early-type stars in the LMC, including the 30 Doradus region. From the high resolution spectra obtained with VLT/UVES we also derive environmental parameters that characterise the local interstellar medium (ISM) in the probed LMC clouds. These include the column density components (including total column density) for the atomic resonance lines of Na I, Ca II, Ti II, K I. In addition, we derive the H I column density from 21 cm line profiles, the total-to-selective visual extinction RV and the gas-to-dust ratio N(H I)/A(V). Furthermore, from atomic line ratios we derive the ionisation balance and relative UV field strength in these environments. We discuss the properties of the LMC ISM in the context of DIB carrier formation. The behaviour of DIBs in the LMC is compared to that of DIBs in different local environmental conditions in the Milky Way. A key result is that in most cases the diffuse band strengths are weak (up to factor 5) with respect to Galactic lines of sight of comparable reddening, EB-V. In the line of sight towards Sk -69 223 the 5780 and 5797 angstrom DIBs are very similar in strength and profile to those observed towards HD 144217, which is typical of an environment exposed to a strong UV field. From the velocity analysis we find that DIB carriers (towards Sk -69 243) are better correlated with the ionised species like Ca II than with neutrals (like Na I and CO). The most significant parameter that governs the behaviour of the DIB carrier is the strength of the UV field. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Univ Nottingham, Sch Chem, Nottingham NG7 2RD, England. NASA, Div Space Sci, Ames Res Ctr, Moffett Field, CA 94035 USA. European Space Agcy, SCI SR, ESTEC, NL-2200 AG Noordwijk, Netherlands. Radboud Univ Nijmegen, Astron Inst, NL-6500 GL Nijmegen, Netherlands. RP Cox, NLJ (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM ncox@science.uva.nl NR 108 TC 59 Z9 59 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 MAR PY 2006 VL 447 IS 3 BP 991 EP U79 DI 10.1051/0004-6361:20053367 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018PO UT WOS:000235777500018 ER PT J AU Oberst, J Matz, KD Roatsch, T Giese, B Hoffmann, H Duxbury, T Neukum, G AF Oberst, J Matz, KD Roatsch, T Giese, B Hoffmann, H Duxbury, T Neukum, G TI Astrometric observations of Phobos and Deimos with the SRC on Mars Express SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE astrometry; ephemerides; planets and satellites : individual : phobos; planets ans satellites : individual : Deimos ID SATELLITES AB Observations of Phobos and Deimos, carried out by the SRC ( Super Resolution Channel) on the Mars Express spacecraft between May 2004 - April 2005, were used to determine the center-of-figure positions of the two Satellites with accuracies of 0.5 - 5 km (Phobos) and 1.0 km ( Deimos). We find that the Phobos and Deimos orbit predictions from NASA-JPL ( Jet Propulsion Laboratory) and ESA-ESOC ( European Space Operation Center) differ substantially among each other and also do not agree with the actually observed positions of the satellites. Hence, our new astrometric data may motivate new efforts for Phobos and Deimos orbit modeling. C1 German Aerosp Ctr DLR, Inst Planetary Res, D-12489 Berlin, Germany. Jet Propuls Lab, Pasadena, CA USA. Free Univ Berlin, D-1000 Berlin, Germany. RP Oberst, J (reprint author), German Aerosp Ctr DLR, Inst Planetary Res, Rutherfordstr 2, D-12489 Berlin, Germany. EM Juergen.Oberst@dlr.de NR 17 TC 18 Z9 18 U1 1 U2 6 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 MAR PY 2006 VL 447 IS 3 BP 1145 EP 1151 DI 10.1051/0004-6361:20053929 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018PO UT WOS:000235777500029 ER PT J AU Mei, S Blakeslee, JP Stanford, SA Holden, BP Rosati, P Strazzullo, V Homeier, N Postman, M Franx, M Rettura, A Ford, H Illingworth, GD Ettori, S Bouwens, RJ Demarco, R Martel, AR Clampin, M Hartig, GF Eisenhardt, P Ardila, DR Bartko, F Benitez, N Bradley, LD Broadhurst, TJ Brown, RA Burrows, CJ Cheng, ES Cross, NJG Feldman, PD Golimowski, DA Goto, T Gronwall, C Infante, L Kimble, RA Krist, JE Lesser, MP Menanteau, F Meurer, GR Miley, GK Motta, V Sirianni, M Sparks, WB Tran, HD Tsvetanov, ZI White, RL Zheng, W AF Mei, S Blakeslee, JP Stanford, SA Holden, BP Rosati, P Strazzullo, V Homeier, N Postman, M Franx, M Rettura, A Ford, H Illingworth, GD Ettori, S Bouwens, RJ Demarco, R Martel, AR Clampin, M Hartig, GF Eisenhardt, P Ardila, DR Bartko, F Benitez, N Bradley, LD Broadhurst, TJ Brown, RA Burrows, CJ Cheng, ES Cross, NJG Feldman, PD Golimowski, DA Goto, T Gronwall, C Infante, L Kimble, RA Krist, JE Lesser, MP Menanteau, F Meurer, GR Miley, GK Motta, V Sirianni, M Sparks, WB Tran, HD Tsvetanov, ZI White, RL Zheng, W TI Evolution of the color-magnitude relation in high-redshift clusters: Blue early-type galaxies and red pairs in RDCS J0910+5422 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : clusters : individual (RDCS J0910+5422); galaxies : elliptical and lenticular, cD; galaxies : evolution ID HUBBLE DEEP FIELD; ELLIPTIC GALAXIES; ADVANCED CAMERA; MS 1054-03; QUANTITATIVE MORPHOLOGY; DISTANT CLUSTERS; S0 GALAXIES; CL 1358+62; CALIBRATION; PHOTOMETRY AB The color-magnitude relation has been determined for the RDCS J0910+5422 cluster of galaxies at redshift z = 1.106. Cluster members were selected from the Hubble Space Telescope Advanced Camera for Surveys (HST ACS) images, combined with ground-based near-IR imaging and optical spectroscopy. The observed early-type color-magnitude relation (CMR) in i(775) - z(850) versus z(850) shows an intrinsic scatter in color of 0.060 +/- 0.009 mag, within 10 from the cluster X-ray emission center. Both the elliptical and the S0 galaxies show small scatter about the CMR of 0.042 +/- 0.010 and 0.044 +/- 0.020 mag, respectively. From the scatter about the CMR, a mean luminosity weighted age t > 3: 3 Gyr (z(f) approximate to 3) is derived for the elliptical galaxies, assuming a simple stellar population modeling (single-burst solar metallicity). Strikingly, the S0 galaxies in RDCS J0910+5422 are systematically bluer in i(775) - z(850), by 0.07 +/- 0.02 mag, than the ellipticals. The ellipticity distribution as a function of color indicates that the face-on S0s in this particular cluster have likely been classified as elliptical. Thus, if anything, the offset in color between the elliptical and S0 populations may be even more significant. The color offset between S0 and E galaxies corresponds to an age difference of approximate to 1 Gyr for a single-burst solar-metallicity model. A solar-metallicity model with an exponential decay in star formation will reproduce the offset for an age of 3.5 Gyr; i.e., the S0s have evolved gradually from star-forming progenitors. The early-type population in this cluster appears to be still forming. The blue early-type disk galaxies in RDCS J0910+5422 likely represent the direct progenitors of the more evolved S0s that follow the same red sequence as elliptical galaxies in other clusters. Thirteen red galaxy pairs are observed, and the galaxies associated in pairs constitute similar to 40% of the CMR galaxies in this cluster. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Calif Davis, Dept Phys, Davis, CA 94516 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. European So Observ, D-85748 Garching, Germany. Univ Naples Federico II, Dipartimento Sci Fisiche, I-80126 Naples, Italy. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Paris Sud 11, F-91405 Orsay, France. INAF, Osservat Astron, I-40127 Bologna, Italy. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. Bartko Sci & Technol, Brighton, CO 80602 USA. CSIC, Inst Astrofis Andalucia, E-18008 Granada, Spain. Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. LLC, Conceptual Anal, Glenn Dale, MD 20769 USA. Royal Observ, Edinburgh EH9 3HJ, Midlothian, Scotland. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 22, Chile. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. WM Keck Observ, Kamuela, HI 96743 USA. RP Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. EM smei@pha.jhu.edu RI White, Richard/A-8143-2012; Clampin, mark/D-2738-2012; Kimble, Randy/D-5317-2012; Ettori, Stefano/N-5004-2015; OI Ettori, Stefano/0000-0003-4117-8617; Benitez, Narciso/0000-0002-0403-7455; Blakeslee, John/0000-0002-5213-3548 NR 69 TC 60 Z9 60 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 MAR 1 PY 2006 VL 639 IS 1 BP 81 EP 94 DI 10.1086/499259 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LI UT WOS:000235836900007 ER PT J AU Freund, MM Freund, FT AF Freund, MM Freund, FT TI Solid solution model for interstellar dust grains and their organics SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry; dust, extinction; infrared : ISM; molecular processes ID INTER-STELLAR GRAINS; POLYCYCLIC AROMATIC-HYDROCARBONS; HYDROGENATED AMORPHOUS-CARBON; MAGNESIUM-OXIDE; INFRARED-EMISSION; SINGLE-CRYSTALS; SUPRATHERMAL ROTATION; UV PHOTODESTRUCTION; SIZE DISTRIBUTIONS; ABSORPTION FEATURE AB We present a dust grain model based on the fundamental principle of solid solutions. The model is applicable to the mineral (silicate) component of the dust in the interstellar medium (ISM). We show that nanometer-sized mineral grains, which condense in the gas-rich outflow of late-stage stars or expanding gas shells of supernova explosions, do not consist of just high melting point oxides or silicates. Instead they form solid solutions with gas-phase components H2O, CO, and CO2 that are omnipresent in environments where the grains condense. Through a series of thermodynamically well-understood solid-state processes, these solid solutions become "parents'' of organic matter that precipitates inside the grains. Thus, the mineral dust grains and their organics become part of the same thermodynamically defined solid phase and, hence, physically inseparable. This model can account for many astronomical observations, which no prior model can adequately address, specifically: (1) Organics in the diffuse ISM are identified by a 3.4 mu m IR band, characteristic of aliphatic hydrocarbons composed of -CH2- and of -CH3 groups. (2) The methylene-to-methyl ratio is nearly constant, implying a CH2:CH3 ratio of similar to 5:2. (3) The intensity ratio between the 9.7 and the 3.4 mu m band is nearly constant, implying a silicate-to-organics ratio of similar to 10:1. (4) In dense clouds the complex 3.4 mu m band is replaced by a weak, featureless 3.47 mu m band. (5) Whereas silicate grains identified by their 9.7 mu m band tend to align in magnetic fields, grains with a strong 3.4 mu m organic signature do not tend to align. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SETI Inst, Mountain View, CA 94043 USA. NASA, GSFC, Astrochem Branch, Astrophys Lab, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Code 685, Greenbelt, MD 20771 USA. EM mfreund@seti.org; ffreund@mail.arc.nasa.gov NR 99 TC 7 Z9 7 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 MAR 1 PY 2006 VL 639 IS 1 BP 210 EP 226 DI 10.1086/498817 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LI UT WOS:000235836900017 ER PT J AU Halfen, DT Apponi, AJ Woolf, N Polt, R Ziurys, LM AF Halfen, DT Apponi, AJ Woolf, N Polt, R Ziurys, LM TI A systematic study of glycolaldehyde in sagittarius B2(N) at 2 and 3 mm: Criteria for detecting large interstellar molecules SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrobiology; astrochemistry; ISM : abundances; ISM : molecules; molecular processes; radio lines : ISM ID MICROWAVE-SPECTRUM; MILLIMETER-WAVE; DIPOLE-MOMENT; SUBMILLIMETER; FORMALDEHYDE; HYDROGEN; COMPLEX; SUGARS; RIBOSE AB A comprehensive study of glycolaldehyde (CH2OHCHO) has been conducted at 2 and 3 mm toward Sgr B2(N) using the Arizona Radio Observatory 12 m telescope. Forty favorable transitions of this species were observed in the range 68-169 GHz. Emission on the 20-70 mK level was detected at frequencies of 38 of these lines, including all transitions arising from the K-a = 0, 1, and 2 ladders. The two transitions not detected were weak and originate in the less populated K-a = 3 levels. Twenty-one percent of the detected lines are distinct, individual features. The remaining transitions are either contaminated by emission from abundant molecules or blended with equivalently weak features. The unblended transitions indicate V-LSR = 62.3 +/- 2.4 km s(-1) and Delta V-1/2 = 8.3 +/- 3.4 km s(-1), line parameters characteristic of organic species in Sgr B2(N). A rotational diagram yields a column density of 5.9 x 10(13) cm(-2) for glycolaldehyde, suggesting a fractional abundance of f (H-2) 5.9 x 10(-11). Observations of formaldehyde toward Sgr B2(N) suggest that H2CO and CH2OHCHO arise from the same gas with an abundance ratio of similar to 1/27. H2CO may function as the precursor to glycolaldehyde in a gas- phase "formose'' reaction. These observations, combined with past results of Hollis et al., provide convincing evidence for the presence of glycolaldehyde in the ISM. This study suggests that an extensive, self- consistent data set is necessary to identify large organic species in interstellar gas. C1 NASA, Astrobiol Inst, Dept Chem,Arizona Radio Observ, Dept Astron,Life Planets Astrobiol Ctr, Tucson, AZ 85721 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP NASA, Astrobiol Inst, Dept Chem,Arizona Radio Observ, Dept Astron,Life Planets Astrobiol Ctr, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM lziurys@as.arizona.edu RI Polt, Robin/E-2339-2017; OI Polt, Robin/0000-0003-0756-3183; Halfen, DeWayne/0000-0003-2483-3616 NR 24 TC 69 Z9 69 U1 0 U2 8 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 MAR 1 PY 2006 VL 639 IS 1 BP 237 EP 245 DI 10.1086/499225 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LI UT WOS:000235836900019 ER PT J AU Hill, JE Morris, DC Sakamoto, T Sato, G Burrows, DN Angelini, L Pagani, C Moretti, A Abbey, AF Barthelmy, S Beardmore, AP Biryukov, VV Campana, S Capalbi, M Cusumano, G Giommi, P Ibrahimov, MA Kennea, J Kobayashi, S Ioka, K Markwardt, C Meszaros, P O'Brien, PT Osborne, JP Pozanenko, AS Perri, M Rumyantsev, VV Schady, P Sharapov, DA Tagliaferri, G Zhang, B Chincarini, G Gehrels, N Wells, A Nousek, JA AF Hill, JE Morris, DC Sakamoto, T Sato, G Burrows, DN Angelini, L Pagani, C Moretti, A Abbey, AF Barthelmy, S Beardmore, AP Biryukov, VV Campana, S Capalbi, M Cusumano, G Giommi, P Ibrahimov, MA Kennea, J Kobayashi, S Ioka, K Markwardt, C Meszaros, P O'Brien, PT Osborne, JP Pozanenko, AS Perri, M Rumyantsev, VV Schady, P Sharapov, DA Tagliaferri, G Zhang, B Chincarini, G Gehrels, N Wells, A Nousek, JA TI GRB 050117: Simultaneous gamma-ray and X-ray observations with the Swift satellite SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID AFTERGLOW EMISSION; BURSTS; TELESCOPE; INJECTION; MISSION; SHOCK AB The Swift Gamma-Ray Burst Explorer performed its first autonomous, X-ray follow-up to a newly detected GRB on 2005 January 17, within 193 s of the burst trigger by the Swift Burst Alert Telescope. While the burst was still in progress, the X-Ray Telescope (XRT) obtained a position and an image for an uncataloged X-ray source simultaneously with the gamma-ray observation. The XRT observed flux during the prompt emission was 1.1 x 10(-8) ergs cm(-2) s(-1) in the 0.5-10 keV energy band. The emission in the X-ray band decreased by 3 orders of magnitude within 700 s, following the prompt emission. This is found to be consistent with the gamma-ray decay when extrapolated into the XRT energy band. During the following 6.3 hr, the XRT observed the afterglow in an automated sequence for an additional 947 s, until the burst became fully obscured by the Earth limb. A faint, extremely slowly decaying afterglow, alpha = -0.21, was detected. Finally, a break in the light curve occurred and the flux decayed with alpha < -1.2. The X-ray position triggered many follow-up observations: no optical afterglow could be confirmed, although a candidate was identified 300 from the XRT position. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Penn State Univ, Dept Astron & Astrophys, Davey Labs 525, University Pk, PA 16802 USA. Inst Space & Astronaut Sci, Japan Aerosp Explorat Agcy, Sagamihara, Kanagawa 2298510, Japan. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. INAF, Osservat Astron Brera, I-23807 Merate, Italy. Univ Leicester, Space Res Ctr, Leicester LE1 7RH, Leics, England. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Moscow MV Lomonosov State Univ, Crimean Lab, Sternberg Astron Inst, Moscow, Russia. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM jhill@milkyway.gsfc.nasa.gov RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; OI Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Rumyantsev, Vasilij/0000-0003-1894-7019; Perri, Matteo/0000-0003-3613-4409; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 34 TC 17 Z9 17 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 MAR 1 PY 2006 VL 639 IS 1 BP 303 EP 310 DI 10.1086/498443 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LI UT WOS:000235836900024 ER PT J AU Mason, KO Blustin, AJ Boyd, P Holland, ST Page, MJ Roming, P Still, M Zhang, B Breeveld, A de Pasquale, M Gehrels, N Gronwall, C Hunsberger, S Ivanushkina, M Landsman, W McGowan, K Nousek, J Poole, T Rhoads, J Rosen, S Schady, P AF Mason, KO Blustin, AJ Boyd, P Holland, ST Page, MJ Roming, P Still, M Zhang, B Breeveld, A de Pasquale, M Gehrels, N Gronwall, C Hunsberger, S Ivanushkina, M Landsman, W McGowan, K Nousek, J Poole, T Rhoads, J Rosen, S Schady, P TI Prompt optical observations of GRB 050319 with the Swift UVOT SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; galaxies : distances and redshifts; gamma rays : bursts; shock waves; X-rays : individual (GRB 050319) ID GAMMA-RAY BURST; INFRARED-EMISSION; REVERSE SHOCK; AFTERGLOW; TELESCOPE; RADIATION; MISSION AB The UVOT telescope on the Swift observatory has detected optical afterglow emission from GRB 050319. The flux declined with a power-law slope of alpha = -0.57 between the start of observations some 230 s after the burst onset (90 s after the burst trigger) until it faded below the sensitivity threshold of the instrument after similar to 5 x 10(4) s. There is no evidence for the rapidly declining component in the early light curve that is seen at the same time in the X-ray band. The afterglow is not detected in UVOT shortward of the B band, suggesting a redshift of about 3.5. The optical V-band emission lies on the extension of the X-ray spectrum, with an optical-to-X-ray slope of beta = 0.8. The relatively flat decay rate of the burst suggests that the central engine continues to inject energy into the fireball for as long as a few x 10(4) s after the burst. C1 UCL, Dept Space & Climate Phys, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP UCL, Dept Space & Climate Phys, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. EM kom@mssl.ucl.ac.uk RI Boyd, Patricia/D-3274-2012; Gehrels, Neil/D-2971-2012 NR 31 TC 21 Z9 21 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 MAR 1 PY 2006 VL 639 IS 1 BP 311 EP 315 DI 10.1086/499293 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LI UT WOS:000235836900025 ER PT J AU Cusumano, G Mangano, V Angelini, L Barthelmy, S Beardmore, AP Burrows, DN Campana, S Cannizzo, JK Capalbi, M Chincarini, G Gehrels, N Giommi, P Goad, MR Hill, JE Kennea, JA Kobayashi, S La Parola, V Malesani, D Meszaros, P Mineo, T Moretti, A Nousek, JA O'Brien, PT Osborne, JP Pagani, C Page, KL Perri, M Romano, P Tagliaferri, G Zhang, B AF Cusumano, G Mangano, V Angelini, L Barthelmy, S Beardmore, AP Burrows, DN Campana, S Cannizzo, JK Capalbi, M Chincarini, G Gehrels, N Giommi, P Goad, MR Hill, JE Kennea, JA Kobayashi, S La Parola, V Malesani, D Meszaros, P Mineo, T Moretti, A Nousek, JA O'Brien, PT Osborne, JP Pagani, C Page, KL Perri, M Romano, P Tagliaferri, G Zhang, B TI Swift XRT observations of the afterglow of GRB 050319 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; X-rays : individual (GRB 050319) ID RAY BURST AFTERGLOWS; ULTRA-VIOLET/OPTICAL TELESCOPE; LIGHT CURVES; INJECTION; MISSION AB Swift discovered the high-redshift GRB 050319 with the Burst Alert Telescope (BAT) and began observing with its narrow-field instruments only 225 s after the burst onset. The afterglow X-ray emission was monitored by the XRT up to 28 days after the burst. The light curve shows a decay with three different phases, each characterized by a distinct slope: an initial steep decay with a power-law index of similar to 5.5, a second phase characterized by a flat decay slope of similar to 0.54, and a third phase with a decay slope of similar to 1.14. During the first phase the spectral energy distribution is softer than in the following two phases, and the photon index is consistent with the GRB prompt spectrum. The extrapolation of the BAT light curve to the XRT band suggests that the initial fast-decaying phase of the XRT afterglow might be the low-energy tail of the prompt emission. The second break in the afterglow light curve occurs about 27,000 s after the burst. The spectral energy distribution before and after the second break does not change, and it can be tentatively interpreted as a jet break or the end of a delayed or continuous energy injection phase. C1 INAF, Ist Astrofis Spaziale, I-90146 Palermo, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. INAF, Osservat Astron Brera, I-23807 Merate, Italy. ASI, Sci Data Ctr, I-00044 Frascati, Italy. Univ Milan, Dipartimento Fis, I-20126 Milan, Italy. SISSA, ISAS, Int Sch Adv Studies, I-34014 Trieste, Italy. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP INAF, Ist Astrofis Spaziale, Via Ugo Malfa 153, I-90146 Palermo, Italy. EM cusumano@pa.iasf.cnr.it RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; OI Mineo, Teresa/0000-0002-4931-8445; Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Perri, Matteo/0000-0003-3613-4409; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 34 TC 42 Z9 43 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 MAR 1 PY 2006 VL 639 IS 1 BP 316 EP 322 DI 10.1086/499292 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LI UT WOS:000235836900026 ER PT J AU Bhattacharyya, S Strohmayer, TE Markwardt, CB Swank, JH AF Bhattacharyya, S Strohmayer, TE Markwardt, CB Swank, JH TI The discovery of a neutron star with a spin frequency of 530 Hz in A1744-361 SO ASTROPHYSICAL JOURNAL LA English DT Article DE equation of state; stars : neutron; stars : rotation; X-rays : binaries; X-rays : bursts; X-rays : individual (A1744-361) ID X-RAY-BURSTS; LIGHT CURVES; BINARY; OSCILLATIONS; EVOLUTION; PULSARS AB We report the detection with the Rossi X-Ray Timing Explorer (RXTE) Proportional Counter Array (PCA) of 530 Hz burst oscillations in a thermonuclear (type I) burst from the transient X-ray source A1744-361. This is only the second burst ever observed from this source, and the first to be seen in any detail. Our results confirm that A1744-361 is a low-mass X-ray binary (LMXB) system harboring a rapidly rotating neutron star. The oscillations are first detected along the rising edge of the burst, and they show evidence for frequency evolution of a magnitude similar to that seen in other burst sources. The modulation amplitude and its increase with photon energy are also typical of burst oscillations. The lack of any strong indication of photospheric radius expansion during the burst suggests a 9 kpc upper limit of the source distance. We also find energy-dependent dips, establishing A1744-361 as a high-inclination, dipping LMXB. The timescale between the two episodes of observed dips suggests an orbital period of similar to 97 minutes. We have also detected a 2-4 Hz quasi-periodic oscillation (QPO) for the first time from this source. This QPO appears consistent with similar to 1 Hz QPOs seen from other high-inclination systems. We searched for kilohertz QPOs and found a suggestive 2.3 sigma feature at 800 Hz in one observation. The frequency, strength, and quality factor are consistent with that of a lower frequency kilohertz QPO, but the relatively low significance argues for caution, so we consider this a tentative detection requiring confirmation. 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; craigm@milkyway.gsfc.nasa.gov; swank@milkyway.gsfc.nasa.gov RI Swank, Jean/F-2693-2012 NR 36 TC 25 Z9 25 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 MAR 1 PY 2006 VL 639 IS 1 BP L31 EP L34 DI 10.1086/501438 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019LJ UT WOS:000235837000008 ER PT J AU Gull, TR Kober, GV Nielsen, KE AF Gull, TR Kober, GV Nielsen, KE TI Eta carinae across the 2003.5 minimum: The character and variability of the ejecta absorption in the near-ultraviolet SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE circumstellar matter; line : identification; stars : individual (eta Carinae); ultraviolet : stars ID TELESCOPE IMAGING SPECTROGRAPH; HOMUNCULUS-NEBULA; TRANSITION-PROBABILITIES; IUE OBSERVATIONS; HIGH-VELOCITY; II EMISSION; SPECTRUM; SPECTROSCOPY; DISCOVERY; LIFETIMES AB We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) high-resolution nearultraviolet (NUV) spectra of eta Car's central source recorded before, during and after the 2003.5 spectroscopic minimum. Our focus is on the narrow absorption lines formed in multiple circumstellar shells, superimposed on the broad P Cygni stellar wind features, and how they respond to the flux variations of eta Car across the minimum. Over 30 separate narrow-line velocity components are identified: three around -46 km s(-1), many between -323 and -587 km s(-1), and a few exceeding -1000 km s(-1). In general, excitation decreases with increasing velocity indicating that the primary excitation is by UV stellar photons and that the slower shells are located closer to the central source. Two well-isolated velocity systems at -146 and -513 km s(-1) display very different spectral characteristics regarding ionization/excitation and respond differently to eta Car's spectroscopic minimum. The -146 km s(-1) shell, associated with the (internal) Little Homunculus, is ionized across the broad spectroscopic maximum but relaxes during the few months long minimum. The -146 km s(-1) component is joined by adjacent velocity components in lines of singly ionized iron-group elements. Ti ii and V ii absorptions appear during the minimum, most likely caused by a decrease in Lyman-ionizing flux. The -513 km s(-1) component, part of the (outer) Homunculus, does not show significant changes in atomic absorptions, but intermediate-velocity components between -369 and -503 km s(-1) vary during the minimum. We present the NUV spectrum and describe its general characteristics, but we focus on identifications of the nebular absorption lines and their variations across the 2003.5 minimum. The complete spectrum between 2380 and 3160 angstrom with line identifications is available in the electronic edition of this paper. C1 Goddard Space Flight Ctr, Explorat Univ Div, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Catholic Univ Amer, Washington, DC 20064 USA. RP Gull, TR (reprint author), Goddard Space Flight Ctr, Explorat Univ Div, Code 667, Greenbelt, MD 20771 USA. EM gull@milkyway.gsfc.nasa.gov; gvieira@milkyway.gsfc.nasa.gov; nielsen@milkyway.gsfc.nasa.gov RI Gull, Theodore/D-2753-2012 OI Gull, Theodore/0000-0002-6851-5380 NR 50 TC 17 Z9 17 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 MAR PY 2006 VL 163 IS 1 BP 173 EP 183 DI 10.1086/500113 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 026RO UT WOS:000236360000008 ER PT J AU Gao, RS Fahey, DW Popp, PJ Marcy, TP Herman, RL Weinstock, EM Smith, JB Sayres, DS Pittman, JV Rosenlof, KH Thompson, TL Bui, PT Baumgardner, DG Anderson, BE Kok, G Weinheimer, AJ AF Gao, RS Fahey, DW Popp, PJ Marcy, TP Herman, RL Weinstock, EM Smith, JB Sayres, DS Pittman, JV Rosenlof, KH Thompson, TL Bui, PT Baumgardner, DG Anderson, BE Kok, G Weinheimer, AJ TI Measurements of relative humidity in a persistent contrail SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE contrail; relative humidity; water vapor; microphysics; ice particles; aircraft emissions; nitric oxide ID IN-SITU OBSERVATIONS; LOWER STRATOSPHERE; EMISSION INDEXES; UPPER TROPOSPHERE; AIRCRAFT EXHAUST; JET AIRCRAFT; NASA ER-2; ICE; CRUISE; TROPOPAUSE AB Persistent contrails are a common feature of the upper troposphere. We describe two methods for intercomparing and evaluating RHi measurements in a persistent contrail with calculated or expected values. The methods were applied to measurements made in the upper troposphere on board an NASA WB-57F aircraft while sampling its own contrail. Included in the analysis are measurements of water vapor pressure, temperature, ice particle number and size, and nitric oxide (NO). The systematic use of these contrail-sampling methods in future studies will improve our understanding of contrail microphysics and the performance of fast-response water and temperature measurements. (c) 2005 Elsevier Ltd. All rights reserved. C1 NOAA, Earth Syst Res Lab, Div Chem Sci, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NASA, Jet Propuls Lab, Pasadena, CA 91109 USA. Harvard Univ, Dept Chem & Biochem, Atmospher Res Project, Cambridge, MA 02138 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Nacl Autonoma Mexico, Ctr Ciencias Atmosfera, Mexico City 04510, DF, Mexico. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Droplet Measurement Technol, Boulder, CO 80301 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. RP Fahey, DW (reprint author), NOAA, Earth Syst Res Lab, Div Chem Sci, 325 Broadway,R CSD6, Boulder, CO 80305 USA. EM david.w.fahey@noaa.gov RI Manager, CSD Publications/B-2789-2015; Rosenlof, Karen/B-5652-2008; Herman, Robert/H-9389-2012; Gao, Ru-Shan/H-7455-2013; Fahey, David/G-4499-2013 OI Rosenlof, Karen/0000-0002-0903-8270; Herman, Robert/0000-0001-7063-6424; Fahey, David/0000-0003-1720-0634 NR 32 TC 7 Z9 7 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD MAR PY 2006 VL 40 IS 9 BP 1590 EP 1600 DI 10.1016/j.atmosenv.2005.11.021 PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 028ZP UT WOS:000236527600003 ER PT J AU Bordini, RH Fisher, M Visser, W Wooldridge, M AF Bordini, RH Fisher, M Visser, W Wooldridge, M TI Verifying multi-agent programs by model checking SO AUTONOMOUS AGENTS AND MULTI-AGENT SYSTEMS LA English DT Article; Proceedings Paper CT 2nd European Agents and Multi-Agent Systems Conference CY DEC 16-17, 2004 CL Barcelona, SPAIN DE agent-oriented programming; AgentSpeak; model checking; spin; JPF ID AGENT AB This paper gives an overview of our recent work on an approach to verifying multi-agent programs. We automatically translate multi-agent systems programmed in the logic-based agent-oriented programming language AgentSpeak into either Promela or Java, and then use the associated Spin and JPF model checkers to verify the resulting systems. We also describe the simplified BDI logical language that is used to write the properties we want the systems to satisfy. The approach is illustrated by means of a simple case study. C1 Univ Durham, Durham DH1 3HP, England. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. RP Univ Durham, Durham DH1 3HP, England. EM R.Bordini@durham.ac.uk; M.Fisher@csc.liv.ac.uk; wvisser@email.arc.nasa.gov; M.J.Wooldridge@csc.liv.ac.uk RI Wooldridge, Michael/A-1329-2012; Bordini, Rafael/G-4919-2012 NR 36 TC 44 Z9 44 U1 0 U2 5 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1387-2532 EI 1573-7454 J9 AUTON AGENT MULTI-AG JI Auton. Agents Multi-Agent Syst. PD MAR PY 2006 VL 12 IS 2 BP 239 EP 256 DI 10.1007/s10458-006-5955-7 PG 18 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA 022ZT UT WOS:000236095400006 ER PT J AU Colombano, SP Shen, WM AF Colombano, SP Shen, WM TI Self-sustaining robotic systems SO AUTONOMOUS ROBOTS LA English DT Editorial Material C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ So Calif, Inst Sci Informat, Los Angeles, CA 90089 USA. Univ So Calif, Dept Comp Sci, Los Angeles, CA 90089 USA. RP Colombano, SP (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-5593 J9 AUTON ROBOT JI Auton. Robot. PD MAR PY 2006 VL 20 IS 2 BP 83 EP 84 DI 10.1007/s10514-006-7535-8 PG 2 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA 038HQ UT WOS:000237210400001 ER PT J AU Huntsberger, TL Sengupta, A AF Huntsberger, TL Sengupta, A TI Game theory basis for control of long-lived lunar/planetary surface robots SO AUTONOMOUS ROBOTS LA English DT Article DE mobile robots; all terrain mobility; game theory; robot control; reconfigurable robots ID SAMPLE RETURN; MOTION; ROVER; EXPLORATION; UNCERTAINTY AB Current and future NASA robotic missions to planetary surfaces are tending toward longer duration and are becoming more ambitious for rough terrain access. For a higher level of autonomy in such missions, the rovers will require behavior that must also adapt to declining health and unknown environmental conditions. The MER (Mars Exploration Rovers) called Spirit and Opportunity have both passed 600 days of life on the Martian surface, with extensions to 1000 days and beyond depending on rover health. Changes in navigational planning due to degradation of the drive motors as they reach their lifetime are currently done on Earth for the Spirit rover. The upcoming 2009 MSL (Mars Science Laboratory) and 2013 AFL (Astrobiology Field Laboratory) missions are planned to last 300-500 days, and will possibly involve traverses on the order of multiple kilometers over challenging terrain. This paper presents a unified coherent framework called SMART (System for Mobility and Access to Rough Terrain) that uses game theoretical algorithms running onboard a planetary surface rover to safeguard rover health during rough terrain access. SMART treats rover motion, task planning, and resource management as a Two Person Zero Sum Game (TPZSG), where the rover is one player opposed by the other player called "nature" representing uncertainty in sensing and prediction of the internal and external environments. We also present preliminary results of some field studies. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM terry.huntsberger@jpl.nasa.gov; abhijit.sengupta@jpl.nasa.gov NR 34 TC 2 Z9 2 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-5593 EI 1573-7527 J9 AUTON ROBOT JI Auton. Robot. PD MAR PY 2006 VL 20 IS 2 BP 85 EP 95 DI 10.1007/s10514-006-5940-7 PG 11 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA 038HQ UT WOS:000237210400002 ER PT J AU Stroupe, A Okon, A Robinson, M Huntsberger, T Aghazarian, H Baumgartner, E AF Stroupe, A Okon, A Robinson, M Huntsberger, T Aghazarian, H Baumgartner, E TI Sustainable cooperative robotic technologies for human and robotic outpost infrastructure construction and maintenance SO AUTONOMOUS ROBOTS LA English DT Article DE multi-robot systems; cooperative transport; space robotics; robotic construction ID VISION AB Robotic Construction Crew (RCC) is a heterogeneous multi-robot system for autonomous acquisition, transport, and precision mating of components in construction tasks. RCC minimizes use of resources constrained by a space environment such as computation, power, communication, and sensing. A behavior-based architecture provides adaptability and robustness despite low computational requirements. RCC successfully performs several construction related tasks in an emulated outdoor environment despite high levels of uncertainty in motions and sensing. This paper provides quantitative results for formation keeping in component transport, precision instrument placement, and construction tasks. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Ashley.Stroupe@jpl.nasa.gov; Avi.Okon@jpl.nasa.gov; Matthew.Robinson@jpl.nasa.gov; Terry.Huntsberger@jpl.nasa.gov; Hrand.Aghazarian@jpl.nasa.gov; Eric.Baumgartner@jpl.nasa.gov NR 27 TC 10 Z9 10 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-5593 EI 1573-7527 J9 AUTON ROBOT JI Auton. Robot. PD MAR PY 2006 VL 20 IS 2 BP 113 EP 123 DI 10.1007/s10514-006-5943-4 PG 11 WC Computer Science, Artificial Intelligence; Robotics SC Computer Science; Robotics GA 038HQ UT WOS:000237210400004 ER PT J AU Bar-Cohen, Y AF Bar-Cohen, Yoseph TI Biomimetics-using nature to inspire human innovation SO BIOINSPIRATION & BIOMIMETICS LA English DT Article AB Evolution has resolved many of nature's challenges leading to lasting solutions. Nature has always inspired human achievements and has led to effective materials, structures, tools, mechanisms, processes, algorithms, methods, systems, and many other benefits (Bar-Cohen Y (ed) 2005 Biomimetics-Biologically Inspired Technologies (Boca Raton, FL: CRC Press) pp 1-552). This field, which is known as biomimetics, offers enormous potential for inspiring new capabilities for exciting future technologies. There are numerous examples of biomimetic successes that involve making simple copies, such as the use of fins for swimming. Others examples involved greater mimicking complexity including the mastery of flying that became possible only after the principles of aerodynamics were better understood. Some commercial implementations of biomimetics, including robotic toys and movie subjects, are increasingly appearing and behaving like living creatures. More substantial benefits of biomimetics include the development of prosthetics that closely mimic real limbs and sensory-enhancing microchips that are interfaced with the brain to assist in hearing, seeing and controlling instruments. A review is given of selected areas that were inspired by nature, and an outlook for potential development in biomimetics is presented. 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 FU National Aeronautics and Space Administration ( NASA) FX Some of the research reported in this manuscript was conducted at the Jet Propulsion Laboratory ( JPL), California Institute of Technology, under a contract with National Aeronautics and Space Administration ( NASA). NR 39 TC 55 Z9 55 U1 4 U2 51 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1748-3182 J9 BIOINSPIR BIOMIM JI Bioinspir. Biomim. PD MAR PY 2006 VL 1 IS 1 BP P1 EP P12 DI 10.1088/1748-3182/1/1/P01 PG 12 WC Engineering, Multidisciplinary; Materials Science, Biomaterials; Robotics SC Engineering; Materials Science; Robotics GA V06BS UT WOS:000207169700003 PM 17671297 ER PT J AU Breininger, DR Toland, B Oddy, DM Legare, ML AF Breininger, DR Toland, B Oddy, DM Legare, ML TI Landcover characterizations and Florida scrub-jay (Aphelocoma coerulescens) population dynamics SO BIOLOGICAL CONSERVATION LA English DT Article DE mapping; fire; fragmentation; demography; dispersal ID KENNEDY-SPACE-CENTER; SOURCE-SINK DYNAMICS; HABITAT FRAGMENTATION; SPECIES RICHNESS; LANDSCAPE CHANGE; FIRE; CONSERVATION; USA; BIODIVERSITY; MANAGEMENT AB Landcover maps demarcate habitat but might underestimate it where species select features smaller than minimum mapping units used to produce maps. Habitat loss is magnified by fragmentation, which produces edge effects, alters dispersal and natural processes (i.e., fire). We quantified how Florida scrub-jay (Aphelocoma coerulescens) habitat varied using traditional landcover maps and methods that considered small focal habitat features (e.g., scrub ridges < 2 ha) within an otherwise unsuitable matrix. We collected 7 years of data on color banded Florida scrub-jays to quantify dispersal and investigate how reproductive success and survival varied with habitat potential (scrub ridges), edge effects, and fire history. Landcover maps that identified only large scrub ridges resulted in a potential population of 354 pairs. Including small scrub ridges within an otherwise unsuitable matrix resulted in a potential population > 774 pairs. Florida scrub-jays occupied less than half the potential habitat, and their population declined most from disrupted fire regimes. Almost 90% of all breeding dispersers remained within the same cluster of territories that they hatched in emphasizing the need to maximize local habitat quantity and quality. Reduced habitat quality, caused by disrupted fire regimes, was a major fragmentation effect that greatly magnified impacts of habitat loss. The disruption of natural processes is seldom identified as a major fragmentation effect, but studies worldwide have accumulated to demonstrate its significance. We advocated specific mapping approaches for species influenced by small habitat features and species dependent on matrix habitats that advance natural processes, such as fire. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Ecol Programs, Dynamac Corp, Dyn 2,Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. Univ Cent Florida, Dept Biol, Orlando, FL 32816 USA. Toland Environm Consulting, Melbourne, FL 32934 USA. RP Breininger, DR (reprint author), NASA, Ecol Programs, Dynamac Corp, Dyn 2,Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. EM breindr@kscems.ksc.nasa.gov NR 72 TC 17 Z9 18 U1 2 U2 15 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD MAR PY 2006 VL 128 IS 2 BP 169 EP 181 DI 10.1016/j.biocon.2005.09.026 PG 13 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 021VY UT WOS:000236015200003 ER PT J AU Pella, J Masuda, M AF Pella, J Masuda, M TI The Gibbs and split-merge sampler for population mixture analysis from genetic data with incomplete baselines SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID DIRICHLET PROCESS MIXTURE; MULTILOCUS GENOTYPE DATA; STOCK COMPOSITION; DISTRIBUTIONS; INFERENCE; MODEL; LOCI AB Although population mixtures often include contributions from novel populations as well as from baseline populations previously sampled, unlabeled mixture individuals can be separated to their sources from genetic data. A Gibbs and split-merge Markov chain Monte Carlo sampler is described for successively partitioning a genetic mixture sample into plausible subsets of individuals from each of the baseline and extra-baseline populations present. The subsets are selected to satisfy the Hardy-Weinberg and linkage equilibrium conditions expected for large, panmictic populations. The number of populations present can be inferred from the distribution for counts of subsets per partition drawn by the sampler. To further summarize the sampler's output, co-assignment probabilities of mixture individuals to the same subsets are computed from the partitions and are used to construct a binary tree of their relatedness. The tree graphically displays the clusters of mixture individuals together with a quantitative measure of the evidence supporting their various separate and common sources. The methodology is applied to several simulated and real data sets to illustrate its use and demonstrate the sampler's superior performance. C1 NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bat Lab, Juneau, AK 99801 USA. RP Masuda, M (reprint author), NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bat Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. EM Michele.Masuda@noaa.gov NR 38 TC 62 Z9 64 U1 1 U2 8 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD MAR PY 2006 VL 63 IS 3 BP 576 EP 596 DI 10.1139/f05-224 PG 21 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 038EI UT WOS:000237201200010 ER PT J AU Hilton, JL Capitaine, N Chapront, J Ferrandiz, JM Fienga, A Fukushima, T Getino, J Mathews, P Simon, JL Soffel, M Vondrak, J Wallace, P Williams, J AF Hilton, JL Capitaine, N Chapront, J Ferrandiz, JM Fienga, A Fukushima, T Getino, J Mathews, P Simon, JL Soffel, M Vondrak, J Wallace, P Williams, J TI Report of the International Astronomical Union Division I Working Group on precession and the ecliptic SO CELESTIAL MECHANICS & DYNAMICAL ASTRONOMY LA English DT Article DE precession and the ecliptic; reference systems ID IAU 1976 SYSTEM; EXPRESSIONS; NUTATION; MODEL; CONSISTENT; QUANTITIES; CONSTANTS; OBLIQUITY AB The IAU Working Group on Precession and the Equinox looked at several solutions for replacing the precession part of the IAU 2000A precession-nutation model, which is not consistent with dynamical theory. These comparisons show that the (Capitaine et al., Astron. Astrophys., 412, 2003a) precession theory, P03, is both consistent with dynamical theory and the solution most compatible with the IAU 2000A nutation model. Thus, the working group recommends the adoption of the P03 precession theory for use with the IAU 2000A nutation. The two greatest sources of uncertainty in the precession theory are the rate of change of the Earth's dynamical flattening, Delta J(2), and the precession rates (i.e. the constants of integration used in deriving the precession). The combined uncertainties limit the accuracy in the precession theory to approximately 2 mas cent(-2). Given that there are difficulties with the traditional angles used to parameterize the precession, z(A), zeta(A), and theta(A), the working group has decided that the choice of parameters should be left to the user. We provide a consistent set of parameters that may be used with either the traditional rotation matrix, or those rotation matrices described in (Capitaine et al., Astron. Astrophys., 412, 2003a) and (Fukushima Astron. J., 126, 2003). We recommend that the ecliptic pole be explicitly defined by the mean orbital angular momentum vector of the Earth-Moon barycenter in the Barycentric Celestial Reference System (BCRS), and explicitly state that this definition is being used to avoid confusion with previous definitions of the ecliptic. Finally, we recommend that the terms precession of the equator and precession of the ecliptic replace the terms lunisolar precession and planetary precession, respectively. C1 USN Observ, Washington, DC 20392 USA. Observ Paris, F-75014 Paris, France. Univ Alicante, E-03080 Alicante, Spain. Inst Mecan Celeste, Paris, France. Natl Astron Observ, Tokyo 181, Japan. Univ Valladolid, Valladolid, Spain. Univ Madras, Madras, Tamil Nadu, India. TU Dresden, Dresden, Germany. Acad Sci Czech Republ, Prague, Czech Republic. Her Majestys Naut Almanac Off, Didcot, Oxon, England. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Hilton, JL (reprint author), USN Observ, Washington, DC 20392 USA. EM jhilton@aa.usno.navy.mil RI Ferrandiz, Jose/A-3491-2009; Vondrak, Jan/G-9057-2014 OI Ferrandiz, Jose/0000-0003-1682-0663; NR 18 TC 28 Z9 31 U1 0 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0923-2958 J9 CELEST MECH DYN ASTR JI Celest. Mech. Dyn. Astron. PD MAR PY 2006 VL 94 IS 3 BP 351 EP 367 DI 10.1007/s10569-006-0001-2 PG 17 WC Astronomy & Astrophysics; Mathematics, Interdisciplinary Applications SC Astronomy & Astrophysics; Mathematics GA 052BD UT WOS:000238204600005 ER PT J AU Sun, S Bleck, R AF Sun, S Bleck, R TI Multi-century simulations with the coupled GISS-HYCOM climate model: control experiments SO CLIMATE DYNAMICS LA English DT Article ID ANTARCTIC CIRCUMPOLAR CURRENT; COORDINATE OCEAN MODEL; EDDY-INDUCED ADVECTION; ONE-DIMENSIONAL MODEL; THERMOHALINE CIRCULATION; SEA-ICE; GLOBAL OCEAN; DEEP CONVECTION; SYSTEM MODEL; EL-NINO AB Multi-century climate simulations obtained with the GISS atmospheric general circulation model coupled to the hybrid-isopycnic ocean model HYCOM are described. Greenhouse gas concentrations are held fixed in these experiments to investigate the coupled model's ability to reproduce the major features of today's climate with minimal drift. Emphasis is placed on the realism of the oceanic general circulation and its effect on air-sea exchange processes. Several model runs using different closures for turbulent vertical exchange as well as improvements to reduce vertical numerical diffusion are compared with climate observations. As in previous studies, the Southern Ocean emerges as the Achilles Heel of the ocean model; deficiencies in its physical representation had far-reaching consequences in early experiments with the coupled model and have provided the strongest impetus for model improvement. The overarching goal of this work is to add diversity to the pool of ocean models available for climate prediction and thereby reduce biases that may stand in the way of assessing climate prediction uncertainty. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Sun, S (reprint author), NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM ssun@giss.nasa.gov; rbleck@giss.nasa.gov RI Sun, Shan/H-2318-2015 NR 67 TC 24 Z9 24 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD MAR PY 2006 VL 26 IS 4 BP 407 EP 428 DI 10.1007/s00382-005-0091-7 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 011ZG UT WOS:000235307400005 ER PT J AU Crucian, B Nelman-Gonzalez, M Sams, C AF Crucian, B Nelman-Gonzalez, M Sams, C TI Rapid flow cytometry method for quantitation of LFA-1-adhesive T cells SO CLINICAL AND VACCINE IMMUNOLOGY LA English DT Article ID CROSS-LINKING; ADHESION; LFA-1; RECEPTORS AB Adhesion molecules are important for leukocyte endothelial attachment and migration to sites of inflammation. The LFA-1 (CD11a and CD18) integrin molecule is constitutively expressed on the T-cell surface. Following T-cell activation, a rapid conformational change of LFA-1 to an "adhesive" state occurs, allowing LFA-1 binding to intracellular cell adhesion molecule type 1 (ICAM-1) -expressing targets, such as antigen-presenting cells. For this study, a rapid flow cytometry method for the quantitation of LFA-1-adhesive T cells following activation was developed. Purified ICAM-1 was bound to 4.5-mu m-diameter beads. Following peripheral blood mononuclear cell activation culture (phorbol myristate acetate and ionomycin), the cells were incubated with the ICAM-1 beads, which allowed attachment to occur. The T cell-bead complexes were then resolved from unbound T cells by How cytometry. Multicolor analysis allowed a complete phenotypic analysis of the adhesive T-cell subsets. Experimental controls indicated that the T cell-bead attachment was LFA-1 and ICAM-1 specific. Very little binding between unactivated T cells and ICAM beads or between activated T cells and plain beads was observed. The kinetics of the response was extremely rapid, with nearly maximal numbers of adhesive T cells observed following 5 min of activation. Scanning electron microscopy analysis was used to characterize legitimate bead-cell binding. By using multicolor cytometry, the responding adhesive T-cell population was usually identified as a distinct subset of T cells with the following phenotype: CD3(+) CD4(+) or CD8(+) CD19(-) CD16(-) CD45RO(+) CD62L(+) CD27(+) CD57(-). A rapid and simple method for the scoring of LFA-1-adhesive T cells was developed and may have significant utility for immune function studies. C1 NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77058 USA. Wyle Labs, Space Physiol & Countermeasures Dept, Houston, TX USA. RP Sams, C (reprint author), NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, SK3, Houston, TX 77058 USA. EM csams@ems.jsc.nasa.gov NR 10 TC 3 Z9 4 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 1556-6811 J9 CLIN VACCINE IMMUNOL JI Clin. Vaccine Immunol. PD MAR PY 2006 VL 13 IS 3 BP 403 EP 408 DI 10.1128/CVI.13.3.403-408.2006 PG 6 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 029WX UT WOS:000236596200015 PM 16522784 ER PT J AU Katta, VR Takahashi, F Linteris, GT AF Katta, VR Takahashi, F Linteris, GT TI Fire-suppression characteristics of CF3H in a cup burner SO COMBUSTION AND FLAME LA English DT Article DE fire suppression; extinction; cup burner; diffusion flames; Halon replacement; flame inhibition ID JET DIFFUSION FLAME; METHANE-AIR FLAMES; PHOSPHORUS-CONTAINING COMPOUNDS; NONPREMIXED FLAMES; PREFERENTIAL DIFFUSION; INHIBITION; FLUOROMETHANES; PREDICTION; SIZES AB A numerical investigation is performed to understand the inhibition characteristics of CF3H in a periodically oscillating methane-air jet diffusion flame formed over a cup burner. A detailed chemical kinetic mechanism having 82 species and 15 10 elementary-reaction steps is used. Calculations made without adding agent yielded an oscillating flame with a flicker frequency of 11 Hz, which compared well with that obtained in the experiment. The minimum concentration of agent required for extinguishing the cup-burner flame is determined by adding CF3H to the air stream and by increasing its volume fraction gradually until the flame is completely extinguished. Addition of CF3H at volume fractions up to 10.05% did not affect the cup-burner flame temperature significantly. Extinction of a cup-burner flame took place as the base of the flame became destabilized, and the unstable flame base moved downstream in search of a new stabilization location. The predicted minimum concentrations of CF3H for extinguishing the flame obtained by (1) replacing the air with CF3H and (2) replacing the N-2 in the air with CF3H are 10.1 and 19.2%, respectively. These concentrations compare favorably with the corresponding measured values of 11.7 and 20.3%, respectively. For validation, calculations are also made for the steady counterflow diffusion flames with different concentrations of CF3H in the air stream and the predicted volume fractions of agent at extinction are in good agreement with the experimental values published in the literature. Examination of the reaction rates for the cup-burner flames indicates that the reactions with fluorinated species reduce the concentration of chain-carrying radicals in the flame. The effect is stronger at the flame base than further up in the trailing part of the flame, leading to destabilization at the flame base prior to extinction in the trailing region, and yielding the observed blowoff-type extinction. (c) 2005 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Innovat Sci Solut Inc, Dayton, OH 45440 USA. NASA, Glenn Res Ctr, Natl Ctr Space Explorat Res Fluids & Combust, Cleveland, OH 44135 USA. Natl Inst Stand & Technol, Fire Res Div, Gaithersburg, MD 20899 USA. RP Katta, VR (reprint author), Innovat Sci Solut Inc, 2766 Indian Ripple Rd, Dayton, OH 45440 USA. EM vrkatta@innssi.com NR 53 TC 23 Z9 27 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD MAR PY 2006 VL 144 IS 4 BP 645 EP 661 DI 10.1016/j.combustflame.2005.09.006 PG 17 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 024JU UT WOS:000236192100001 ER PT J AU Murri, GB Schaff, JR AF Murri, GB Schaff, JR TI Fatigue life methodology for tapered hybrid composite flexbeams SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE flexbeam; polymer matrix composite; fatigue, fracture toughness; delamination AB Nonlinear-tapered flexbeam specimens from a full-size composite helicopter rotor hub flexbeam were tested under combined constant axial tension and cyclic bending loads. Two different graphite/glass hybrid configurations tested under cyclic loading failed by delamination in the tapered region. A 2-D finite element model was developed which closely approximated the flexbeam geometry, boundary conditions, and loading. The analysis results from two geometrically nonlinear finite element codes, ANSYS and ABAQUS, are presented and compared. Strain energy release rates (G) associated with simulated delamination growth in the flexbeams are presented from both codes. These results compare well with each other and suggest that the initial delamination growth from the tip of the ply-drop toward the thick region of the flexbeam is strongly mode II. The peak calculated G values were used with material characterization data to calculate fatigue life curves for comparison with test data. A curve relating maximum surface strain to number of loading cycles at delamination onset compared well with the test results. (c) 2005 Elsevier Ltd. All rights reserved. C1 USA, Res Lab, Vehicle Technol Directorate, NASA,Langley Res Ctr, Hampton, VA 23681 USA. Sikorsky Aircraft, Stratford, CT 06601 USA. RP Murri, GB (reprint author), USA, Res Lab, Vehicle Technol Directorate, NASA,Langley Res Ctr, Hampton, VA 23681 USA. EM gretchen.b.murri@nasa.gov NR 15 TC 9 Z9 9 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PD MAR PY 2006 VL 66 IS 3-4 BP 499 EP 508 DI 10.1016/j.compscitech.2005.06.010 PG 10 WC Materials Science, Composites SC Materials Science GA 008QA UT WOS:000235054600014 ER PT J AU Ray, RD AF Ray, RD TI Secular changes of the M-2 tide in the Gulf of Maine SO CONTINENTAL SHELF RESEARCH LA English DT Article DE tides; Gulf of Maine; tidal changes ID SEA-LEVEL RISE; SEMIDIURNAL TIDE; FUNDY; BAY; TRENDS; RANGE AB Analyses of long time series of hourly tide-gauge data at four stations in the Gulf of Maine reveal that the amplitude of the M-2 tide underwent a nearly linear secular increase throughout most of the 20th century. In the early 1980s, however, the amplitude of M-2 abruptly dropped. Sea level changes alone appear inadequate to explain either the long-term trend or the recent trend discontinuity. Tidal models that account for Holocene sea level rise do predict an amplification of M-2, but much smaller than the Currently observed trends. Nor do recent annual mean sea levels correlate with the recent trend discontinuity. Some unknown fraction of the open Atlantic may be similarly affected, since the M, discontinuity, but not the long-term secular increase in the tide, is evident also at Halifax. Published by Elsevier Ltd. C1 NASA, Goddard Space Flight Ctr, Space Geodesy Branch, Greenbelt, MD 20771 USA. RP Ray, RD (reprint author), NASA, Goddard Space Flight Ctr, Space Geodesy Branch, Code 697, Greenbelt, MD 20771 USA. EM richard.ray@nasa.gov RI Ray, Richard/D-1034-2012 NR 17 TC 29 Z9 30 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD MAR PY 2006 VL 26 IS 3 BP 422 EP 427 DI 10.1016/j.csr.2005.12.005 PG 6 WC Oceanography SC Oceanography GA 028AM UT WOS:000236457700009 ER PT J AU Lam, CW James, JT McCluskey, R Arepalli, S Hunter, RL AF Lam, CW James, JT McCluskey, R Arepalli, S Hunter, RL TI A review of carbon nanotube toxicity and assessment of potential occupational and environmental health risks SO CRITICAL REVIEWS IN TOXICOLOGY LA English DT Review DE cardiopulmonary diseases; fibrosis; fullerenes; granulomas; intratracheal instillation; multi-wall carbon nanotubes; nanomaterials; nanotechnology; natural gas combustion; particulate matter; PM2.5; pulmonary toxicity; risk assessment; single-wall carbon nanotubes ID CHEMICAL-VAPOR-DEPOSITION; PARTICULATE AIR-POLLUTION; INTRATRACHEAL INSTILLATION; PULMONARY TOXICITY; CATALYTIC GROWTH; SIMULATED LUNAR; LASER-ABLATION; MARTIAN DUSTS; SINGLE; EXPOSURE AB Nanotechnology has emerged at the forefront of science research and technology development. Carbon nanotubes (CNTs) are major building blocks of this new technology. They possess unique electrical, mechanical, and thermal properties, with potential wide applications in the electronics, computer, aerospace, and other industries. CNTs exist in two forms, single-wall (SWCNTs) and multi-wall (MWCNTs). They are manufactured predominately by electrical arc discharge, laser ablation and chemical vapor deposition processes; these processes involve thermally stripping carbon atoms off from carbon-bearing compounds. SWCNT formation requires catalytic metals. There has been a great concern that if CNTs, which are very light, enter the working environment as suspended particulate matter (PM) of respirable sizes, they could pose an occupational inhalation exposure hazard. Very recently, MWCNTs and other carbonaceous nanoparticles in fine (< 2.5 mu m) PM aggregates have been found in combustion streams of methane, propane, and natural-gas flames of typical stoves; indoor and outdoor fine PM samples were reported to contain significant fractions of MWCNTs. Here we review several rodent studies in which test dusts were administered intratracheally or intrapharyngeally to assess the pulmonary toxicity of manufactured CNTs, and a few in vitro studies to assess biomarkers of toxicity released in CNT-treated skin cell cultures. The results of the rodent studies collectively showed that regardless of the process by which CNTs were synthesized and the types and amounts of metals they contained, CNTs were capable of producing inflammation, epithelioid granulomas (microscopic nodules), fibrosis, and biochemical/toxicological changes in the lungs. Comparative toxicity studies in which mice were given equal weights of test materials showed that SWCNTs were more toxic than quartz, which is considered a serious occupational health hazard if it is chronically inhaled; ultrafine carbon black was shown to produce minimal lung responses. The differences in opinions of the investigators about the potential hazards of exposures to CNTs are discussed here. Presented here are also the possible mechanisms of CNT pathogenesis in the lung and the impact of residual metals and other impurities on the toxicological manifestations. The toxicological hazard assessment of potential human exposures to airborne CNTs and occupational exposure limits for these novel compounds are discussed in detail. Environmental fine PM is known to form mainly from combustion of fuels, and has been reported to be a major contributor to the induction of cardiopulmonary diseases by pollutants. Given that manufactured SWCNTs and MWCNTs were found to elicit pathological changes in the lungs, and SWCNTs (administered to the lungs of mice) were further shown to produce respiratory function impairments, retard bacterial clearance after bacterial inoculation, damage the mitochondrial DNA in aorta, increase the percent of aortic plaque, and induce atherosclerotic lesions in the brachiocephalic artery of the heart, it is speculated that exposure to combustion-generated MWCNTs in fine PM may play a significant role in air pollution-related cardiopulmonary diseases. Therefore, CNTs from manufactured and combustion sources in the environment could have adverse effects on human health. C1 NASA, Lyndon B Johnson Space Ctr, JSC Toxicol Grp, Wyle Labs, Houston, TX 77058 USA. Univ Texas, Sch Med, Dept Pathol & Lab Med, Houston, TX 77030 USA. NASA, Lyndon B Johnson Space Ctr, Med Operat Branch, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, JSC Nanomat Grp, Houston, TX 77058 USA. ERC Inc, Houston, TX USA. RP Lam, CW (reprint author), NASA, Lyndon B Johnson Space Ctr, JSC Toxicol Grp, Wyle Labs, SF23 Wyle, Houston, TX 77058 USA. EM Chiu-wing.Lam-l@nasa.gov RI Arepalli, Sivaram/A-5372-2010 NR 101 TC 649 Z9 674 U1 59 U2 542 PU INFORMA HEALTHCARE PI LONDON PA TELEPHONE HOUSE, 69-77 PAUL STREET, LONDON EC2A 4LQ, ENGLAND SN 1040-8444 J9 CRIT REV TOXICOL JI Crit. Rev. Toxicol. PD MAR PY 2006 VL 36 IS 3 BP 189 EP 217 DI 10.1080/10408440600570233 PG 29 WC Toxicology SC Toxicology GA 031WI UT WOS:000236735500001 PM 16686422 ER PT J AU Anyamba, A Chretien, JP Formenty, PBH Small, J Tucker, CJ Malone, JL El Bushra, H Martin, V Linthicum, KJ AF Anyamba, A Chretien, JP Formenty, PBH Small, J Tucker, CJ Malone, JL El Bushra, H Martin, V Linthicum, KJ TI Rift Valley fever potential, Arabian Peninsula SO EMERGING INFECTIOUS DISEASES LA English DT Letter C1 USDA, Ctr Med Agr & Vet Entomol, Gainesville, FL 32608 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Dept Def Global Emerging Infect Surveillance & Re, Silver Spring, MD USA. World Hlth Org, Geneva, Switzerland. Worl Hlth Org, Cairo, Egypt. Food & Agr Org, Rome, Italy. RP Linthicum, KJ (reprint author), USDA, Ctr Med Agr & Vet Entomol, 1600-1700 SW 23rd Dr, Gainesville, FL 32608 USA. EM klinthicum@gainesville.usda.ufl.edu RI Valle, Ruben/A-7512-2013; OI Chretien, Jean-Paul/0000-0001-8143-6823 NR 9 TC 14 Z9 16 U1 0 U2 1 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD MAR PY 2006 VL 12 IS 3 BP 518 EP 520 PG 3 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 020PP UT WOS:000235922300030 PM 16710979 ER PT J AU Saphores, JDM Nixon, H Ogunseitan, OA Shapiro, AA AF Saphores, JDM Nixon, H Ogunseitan, OA Shapiro, AA TI Household willingness to recycle electronic waste - An application to California SO ENVIRONMENT AND BEHAVIOR LA English DT Article DE recycling behavior; electronic waste; principal components analysis; seminonparametric extended ordered probit ID SOLID-WASTE; ENVIRONMENTAL CONCERN; SITUATIONAL FACTORS; BEHAVIOR; DETERMINANTS; MANAGEMENT; ATTITUDES; PARTICIPATION; CONSERVATION; INTENTIONS AB Electronic waste (e-waste) has become the main contributor of lead to landfills in the United States. Households also store large volumes of e-waste, yet little is known about their willingness to recycle e-waste. This article starts filling this gap based on a 2004 mail survey of California households. Using multivariate models, the authors find that gender, education, convenience, and environmental beliefs but not income or political affiliation are key factors explaining the willingness to drop off e-waste at recycling centers. A comparison of an ordered probit with a semi-nonparametric extended ordered probit model of the survey responses shows that the latter better predicts less frequent answers. The results suggest targeting public education programs about recycling at teenagers or younger adults and making recycling more convenient for older adults; moreover, e-waste drop-off centers should first be created in communities that already offer curbside collection programs for conventional recyclable products. C1 Univ Calif Irvine, Dept Planning Policy & Design, Sch Social Ecol, Irvine, CA 92717 USA. Univ Calif Irvine, Dept Environm Hlth Sci & Policy, Sch Social Ecol, Irvine, CA 92717 USA. CALTECH, Enterprise Engn Div, Jet Prop Lab, Pasadena, CA 91125 USA. RP Saphores, JDM (reprint author), Univ Calif Irvine, Dept Planning Policy & Design, Sch Social Ecol, Irvine, CA 92717 USA. OI Ogunseitan, Oladele/0000-0003-1317-6219 NR 51 TC 71 Z9 73 U1 4 U2 33 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0013-9165 J9 ENVIRON BEHAV JI Environ. Behav. PD MAR PY 2006 VL 38 IS 2 BP 183 EP 208 DI 10.1177/0013916505279045 PG 26 WC Environmental Studies; Psychology, Multidisciplinary SC Environmental Sciences & Ecology; Psychology GA 013DH UT WOS:000235389300003 ER PT J AU Ivanov, AV Zolensky, ME Kononkova, NN Yang, SV Stroganov, IA AF Ivanov, A. V. Zolensky, M. E. Kononkova, N. N. Yang, S. V. Stroganov, I. A. TI Kaidun meteorite: Crystals of oxides in cavities SO GEOCHEMISTRY INTERNATIONAL LA English DT Article ID AQUEOUS ALTERATION AB Cavities in two texturally and genetically distinct clasts of the Kaidun meteorite were found out to contain crystals of distinct morphology, but of a similar composition. Cavities in chondrite breccia #d3A contain thin (< 4 mu m) elongated ( up to 25 mu m long) crystals that grew perpendicular to the walls of the cavity. The walls of the cavities in partly fused clast #d( 3- 5) D are covered with clusters of acicular crystals. In both clasts, the crystals are covered by films of phyllosilicates and always have a composition approximated by the formula (Mg, Fe, Mn)(5)Al2O8 center dot n H2O. No mineral phase of this composition has ever been found in nature. The genesis of the mineral phases in the cavities is thought to be related to the crystallization from a fluid of similar composition. The fluid was produced during the cooling of the melt that produced clast # d( 3- 5) D. The unusual composition of the crystals testifies that this fluid had an unusual composition. This can be explained by the unique nature of clast # d( 3- 5) D, for which there are good reasons to propose a Martian origin. C1 Russian Acad Sci, VI Vernadskii Inst Geochem & Analyt Chem, Moscow 119991, Russia. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Lockheed Engn & Sci Co, Houston, TX 77058 USA. RP Ivanov, AV (reprint author), Russian Acad Sci, VI Vernadskii Inst Geochem & Analyt Chem, Ul Kosygina 19, Moscow 119991, Russia. EM andrei_ivanov@geokhi.ru NR 9 TC 3 Z9 3 U1 0 U2 2 PU MAIK NAUKA/INTERPERIODICA/SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 0016-7029 J9 GEOCHEM INT+ JI Geochem. Int. PD MAR PY 2006 VL 44 IS 3 BP 249 EP 257 DI 10.1134/S0016702906030037 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 154QU UT WOS:000245523200003 ER PT J AU Chabot, NL Campbell, AJ Jones, JH Humayun, M Lauer, HV AF Chabot, NL Campbell, AJ Jones, JH Humayun, M Lauer, HV TI The influence of carbon on trace element partitioning behavior SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CORE-MANTLE INTERACTION; HF-W CHRONOMETRY; FE-NI-S; IRON-METEORITES; EARTHS CORE; OS-186-OS-187 SYSTEMATICS; SIDEROPHILE ELEMENTS; ISOTOPE EVIDENCE; OXYGEN FUGACITY; METAL AB Carbon has been proposed as a potential light element in planetary cores, included in models of planetary core formation, and found in meteoritic samples and minerals. To better understand the effect of C on the partitioning behavior of elements, solid/liquid partition coefficients (D = (solid metal)/(liquid metal)) were determined for 17 elements (As, An, Co, Cr, Cu, Ga, Ge, Ir, Ni, Os, Pd, Pt, Re, Ru, Sb, Sri, and W) over a range of C contents in the Fe-Ni-C system at 1 atm. The partition coefficients for the majority of the elements increased as the C content of the liquid increased, an effect analogous to that of S for many of the elements. In contrast, three of the elements, Cr, Re, and W, were found to have anthracophile (C-loving) preferences, partitioning more strongly into the metallic liquid as the C content increased, resulting in decreases to their partition coefficients. For half of the elements examined, the prediction that partitioning in the Fe-Ni-S and Fe-Ni-C systems could be parameterized using a single set of variables was not supported. The effects of S and C on elemental partitioning behavior can be quite different; consequently, the presence of different non-metals can result in different fractionation patterns, and that uniqueness offers the opportunity to gain insight into the evolution of planetary bodies. (c) 2005 Elsevier Inc. All rights reserved. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Florida State Univ, Dept Geol Sci, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. ESCB Barrios Technol, Houston, TX 77258 USA. RP Chabot, NL (reprint author), Johns Hopkins Univ, Appl Phys Lab, 11100 Johns Hopkins Rd, Laurel, MD 20723 USA. EM Nancy.Chabot@jhuapl.edu RI Chabot, Nancy/F-5384-2015; OI Chabot, Nancy/0000-0001-8628-3176; Humayun, Munir/0000-0001-8516-9435 NR 48 TC 46 Z9 46 U1 2 U2 8 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 MAR 1 PY 2006 VL 70 IS 5 BP 1322 EP 1335 DI 10.1016/j.gca.2005.11.011 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 020ZJ UT WOS:000235951700015 ER PT J AU Catling, DC Wood, SE Leovy, C Montgomery, DR Greenberg, HM Glein, CR Moore, JM AF Catling, DC Wood, SE Leovy, C Montgomery, DR Greenberg, HM Glein, CR Moore, JM TI Light-toned layered deposits in Juventae Chasma, Mars SO ICARUS LA English DT Article DE Mars; Mars; surface; geological processes; mineralogy; infrared observations ID THERMAL EMISSION SPECTROMETER; MARTIAN OUTFLOW CHANNELS; IMAGING-SYSTEM THEMIS; VALLES-MARINERIS; MERIDIANI-PLANUM; GENERAL-CIRCULATION; SURFACE; ICE; EVOLUTION; INERTIA AB We examine hypotheses for the formation of light-toned layered deposits in Juventae Chasma using a combination of data from Mars Global Surveyor's Mars Orbiter Camera (MOC), Mars Orbiter Laser Altimeter (MOLA), and Thermal Emission Spectrometer (TES), as well as Mars Odyssey's Thermal Emission Imaging System (THEMIS). We divide Juventae Chasma into geomorphic units of (i) chasm wall rock, (ii) heavily cratered hummocky terrain, (iii) a mobile and largely crater-free sand sheet on the chasm floor, (iv) light-toned layered outcrop (LLO) material, and (v) chaotic terrain. Using surface temperatures derived from THEMIS infrared data and slopes from MOLA, we derive maps of thermal inertia, which are consistent with the geomorphic units that we identify. LLO thermal inertias range from similar to 400 to 850 J m(-2) K-1 s(-1/2). Light-toned layered outcrops are distributed over a remarkably wide elevation range (similar to 5.8 km) from the chasm floor to the adjacent plateau surface. Geomorphic features, the absence of small craters, and high thermal inertia show that the LLOs are composed of sedimentary rock that is eroding relatively rapidly in the present epoch. We also present evidence for exhumation of LLO material from the west wall of the chasm, within chaotic and hummocky terrains, and within a small depression in the adjacent plateau. The data imply that at least some of the LLO material was deposited long before the adjacent Hesperian plateau basalts, and that Juventae Chasma underwent, and may still be undergoing, enlargement along its west wall due to wall rock collapse, chaotic terrain evolution, and exposure and removal of LLO material. The new data allow us to reassess possible origins of the LLOs. Gypsum, one of the minerals reported elsewhere as found in Juventae Chasma LLO material, forms only at low temperatures (< 60 degrees C) and thus excludes a volcanic origin. Instead, the data are consistent with either multiple occurrences of lacustrine or airfall deposition over an extended period of time prior to emplacement of Hesperian lava flows on the plateau above the chasm. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Univ Washington, Astrobiol Program, Seattle, WA 98195 USA. Univ Bristol, Dept Earth Sci, Bristol BS8 1RJ, Avon, England. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Catling, DC (reprint author), Univ Washington, Dept Atmospher Sci, Box 351640, Seattle, WA 98195 USA. EM davidc@atmos.washington.edu RI Catling, David/D-2082-2009; Wood, Stephen/R-5592-2016; OI Wood, Stephen/0000-0002-9330-434X; Catling, David/0000-0001-5646-120X NR 62 TC 60 Z9 60 U1 1 U2 9 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 MAR PY 2006 VL 181 IS 1 BP 26 EP 51 DI 10.1016/j.icarus.2005.10.020 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900003 ER PT J AU Schuerger, AC Richards, JT Newcombe, DA Venkateswaran, K AF Schuerger, AC Richards, JT Newcombe, DA Venkateswaran, K TI Rapid inactivation of seven Bacillus spp. under simulated Mars UV irradiation SO ICARUS LA English DT Article DE Mars; Mars; surface; exobiology ID MARTIAN ENVIRONMENTS; SPACECRAFT SURFACES; SOLAR-RADIATION; SURVIVAL; MICROORGANISMS; PATHFINDER; RESISTANCE; CONTAMINATION; TERRESTRIAL; EXPLORATION AB Seven Bacillus spp. were exposed to simulations of Mars-normal UV fluence rates in order to study the effects of UV irradiation on microbial survival. A UV illumination system was calibrated to deliver 9.78 W m(-2) (35.2 kJ m(-2) h(-1)) of UVC + UVB irradiation (200-320 nm) to microbial samples, thus creating a clear-sky simulation (0.5 optical depth) of equatorial Mars. The Bacillus spp. studied were: B. licheniformis KL-196, B. megaterium KL-197, B. nealsonii FO-092, B. pumilus FO-36B, B. pumilus SAFR-032, B. subtilis 42HS1, and B. subtilis HA101. The bacteria were prepared as thin monolayers of endospores on aluminum coupons in order to simulate contaminated spacecraft surfaces. Bacterial monolayers were exposed to Mars UV irradiation for time-steps of 0, 0.25, 0.5, 1, 5, 15, 30, 60, 120, or 180 min. The surviving enclospores were then assayed with a Most Probable Numbers (MPN) procedure and with a culture-based assay that utilized a bacillus spore germination medium. Results indicated that B. pumilus SAFR-032 was the most resistant, and B. subtilis 42HS-1 and B. megaterium were the most sensitive of the seven strains exposed to martian UV fluence rates. Bacillus subtilis 42HS1 and B. megaterium were inactivated after 30 min exposure to Mars UV, while B. pumilus SAFR-032 required 180 min for full inactivation in both assays. Spores of B. pumilus SAFR-032 exhibited significantly different inactivation kinetics suggesting that this wild type isolate also was more resistant than the standard dosimetric strain, B. subtilis HA101 Although the various Bacillus spp. exhibited diverse levels of UV resistance, none were immune to UV irradiation, and, thus, all species would be expected to be inactivated on Sun-exposed spacecraft surfaces within a few tens-of-minutes to a few hours on sol I under clear-sky conditions on equatorial Mars. The inactivation kinetics of all seven Bacillus spp. support the conclusion that significant levels of bioload reductions are possible on Sun-exposed spacecraft surfaces in very short time periods under clear-sky conditions on Mars. However, the presence of UV resistant microbes on spacecraft surfaces rapidly covered in dust during landing operations, and non-Sun-exposed surfaces of spacecraft remain concerns that must continue to be addressed through adequate spacecraft sanitizing procedures prior to launch. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Florida, Dept Plant Pathol, Space Life Sci Lab, Kennedy Space Ctr, FL 32899 USA. Dynamac Corp, Kennedy Space Ctr, FL 32899 USA. CALTECH, Jet Prop Lab, Biotechnol & Planetary Protect Grp, Pasadena, CA 91109 USA. RP Schuerger, AC (reprint author), Univ Florida, Dept Plant Pathol, Space Life Sci Lab, Bldg M6-1025, Kennedy Space Ctr, FL 32899 USA. EM acschuerger@ifas.ufl.edu NR 38 TC 50 Z9 51 U1 0 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 J9 ICARUS JI Icarus PD MAR PY 2006 VL 181 IS 1 BP 52 EP 62 DI 10.1016/j.icarus.2005.10.008 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900004 ER PT J AU Pravec, P Scheirich, P Kusirak, P Sarounova, L Mottola, S Hahn, G Brown, P Esquerdo, G Kaiser, N Krzeminski, Z Pray, DP Warner, BD Harris, AW Nolan, MC Howell, ES Benner, LAM Margot, JL Galad, A Holliday, W Hicks, MD Krugly, YN Tholen, D Whiteley, R Marchis, F DeGraff, DR Grauer, A Larson, S Velichko, FP Cooney, WR Stephens, R Zhu, J Kirsch, K Dyvig, R Snyder, L Reddy, V Moore, S Gajdos, S Vilagi, J Masi, G Higgins, D Funkhouser, G Knight, B Slivan, S Behrend, R Grenon, M Burki, G Roy, R Demeautis, C Matter, D Waelchli, N Revaz, Y Klotz, A Rieugne, A Thierry, P Cotrez, V Brunetto, L Kober, G AF Pravec, P Scheirich, P Kusirak, P Sarounova, L Mottola, S Hahn, G Brown, P Esquerdo, G Kaiser, N Krzeminski, Z Pray, DP Warner, BD Harris, AW Nolan, MC Howell, ES Benner, LAM Margot, JL Galad, A Holliday, W Hicks, MD Krugly, YN Tholen, D Whiteley, R Marchis, F DeGraff, DR Grauer, A Larson, S Velichko, FP Cooney, WR Stephens, R Zhu, J Kirsch, K Dyvig, R Snyder, L Reddy, V Moore, S Gajdos, S Vilagi, J Masi, G Higgins, D Funkhouser, G Knight, B Slivan, S Behrend, R Grenon, M Burki, G Roy, R Demeautis, C Matter, D Waelchli, N Revaz, Y Klotz, A Rieugne, A Thierry, P Cotrez, V Brunetto, L Kober, G TI Photometric survey of binary near-Earth asteroids SO ICARUS LA English DT Article DE asteroids; photometry ID FOLLOW-UP PROGRAM; TUMBLING ASTEROIDS; DOUBLET CRATERS; 1996 FG(3); MAIN-BELT; OBJECTS; LIGHTCURVES; POPULATION; EVENTS; SYSTEM AB Photometric data on 17 binary near-Earth asteroids (15 of them are certain detections, two are probables) were analysed and characteristic properties of the near-Earth asteroid (NEA) binary population were inferred. We have found that binary systems with a secondary-to-primary mean diameter ratio D-s/D-p >= 0.18 concentrate among NEAs smaller than 2 km in diameter; the abundance of such binaries decreases significantly among larger NEAs. Secondaries show an upper size limit of D-s = 0.5-1 km. Systems with D-s/D-p <= 0.5 are abundant but larger satellites are significantly less common. Primaries have spheroidal shapes and they rotate rapidly, with periods concentrating between 2.2 to 2.8 It and with a tail of the distribution up to similar to 4 It. The fast rotators are close to the critical spin for rubble piles with bulk densities about 2 g/cm(3). Orbital periods show an apparent cut-off at P-orb similar to 11 h; closer systems with shorter orbital periods have not been discovered, which is consistent with the Roche limit for strengthless bodies. Secondaries are more elongated on average than primaries. Most, but not all, of their rotations appear to be synchronized with the orbital motion; nonsynchronous secondary rotations may occur especially among wider systems with P-orb > 20 h. The specific total angular momentum of most of the binary systems is similar to within 20% and close to the angular momentum of a sphere with the same total mass and density, rotating at the disruption limit; this suggests that the binaries were created by mechanism(s) related to rotation near the critical limit and that they neither gained nor lost significant amounts of angular momentum during or since formation. A comparison with six small asynchronous binaries detected in the main belt of asteroids suggests that the population extends beyond the region of terrestrial planets, but with characteristics shifted to larger sizes and longer periods. The estimated mean proportion of binaries with D-s/D-p >= 0. 18 among NEAs larger than 0.3 km is 15 +/- 4%. Among fastest rotating NEAs larger than 0.3 km with periods between 2.2 and 2.8 h, the mean proportion of such binaries is (66 +/- (10)(12))%. (c) 2005 Elsevier Inc. All rights reserved. C1 Acad Sci Czech Republ, Astron Inst, CZ-25165 Ondrejov, Czech Republic. DLR, Inst Planetary Res, D-12489 Berlin, Germany. Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada. Carbuncle Hill Observ, Coventry, RI 02816 USA. Palmer Divide Obser, Colorado Springs, CO 80908 USA. Space Sci Inst, Fukui 91011, Japan. Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00612 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. FMFI UK, Modra Observ, Dept Astron Phys Earth & Meteorol, SK-84248 Bratislava, Slovakia. River Oaks Observ, New Braunfels, TX 78132 USA. Kharkiv Natl Univ, Inst Astron, UA-61022 Kharkov, Ukraine. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Alfred Univ, Alfred, NY 14802 USA. Univ Arkansas, Dept Phys & Astron, Little Rock, AR 72204 USA. BRAS Highland Rd Pk Observ, BREC, LSU, Baton Rouge, LA 70810 USA. Santana Observ, Rancho Cucamonga, CA 91737 USA. Chinese Acad Sci, Beijing Astron Observ, Beijing 100012, Peoples R China. Badlands Observ, Quinn, SD 57775 USA. MacLean Tahoe Observ, Incline Village, NV 89450 USA. Univ N Dakota, Dept Space Studies, Grand Forks, ND 58202 USA. Smith Coll, Dept Astron, Northampton, MA 01063 USA. Univ Roma Tor Vergata, Dept Phys, I-00133 Rome, Italy. Campo Catino Observ, I-03016 Guarcino, Italy. Hunters Hill Observ, Canberra, ACT 2913, Australia. Wellesley Coll, Whitin Observ, Dept Astron, Wellesley, MA 02481 USA. Observ Geneva, CH-1290 Chavannes Des Bois, Switzerland. Blauvac Observ, F-84570 Blauvac, France. Village Neuf Observ, F-68000 St Louis, France. FX Bagnoud Observ, CH-3961 St Luc, Switzerland. St Caprais, F-81800 Rabastens, France. Observ Haute Provence, F-04870 St Michel, France. St Helene Observ, F-33480 St Helene, France. Antibes Observ, F-06600 Antibes, France. RP Pravec, P (reprint author), Acad Sci Czech Republ, Astron Inst, Fricova 1, CZ-25165 Ondrejov, Czech Republic. EM ppravec@asu.cas.ez RI Margot, Jean-Luc/A-6154-2012; Marchis, Franck/H-3971-2012; Nolan, Michael/H-4980-2012; Pravec, Petr/G-9037-2014; Scheirich, Peter/H-4331-2014; Galad, Adrian/G-9011-2014; OI Margot, Jean-Luc/0000-0001-9798-1797; Nolan, Michael/0000-0001-8316-0680; Scheirich, Peter/0000-0001-8518-9532; Reddy, Vishnu/0000-0002-7743-3491 NR 83 TC 130 Z9 130 U1 1 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 MAR PY 2006 VL 181 IS 1 BP 63 EP 93 DI 10.1016/j.icarus.2005.10.014 PG 31 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900005 ER PT J AU Hardersen, PS Gaffey, MJ Cioutis, EA Abell, PA Reddy, V AF Hardersen, PS Gaffey, MJ Cioutis, EA Abell, PA Reddy, V TI Near-infrared spectral observations and interpretations for S-asteroids 138 Tolosa, 306 Unitas, 346 Hermentaria, and 480 Hansa SO ICARUS LA English DT Review DE asteroids; composition; mineralogy; spectroscopy; thermal histories ID ORDINARY CHONDRITES; ORTHO-PYROXENE; SPECTROSCOPIC SURVEY; CA-RICH; POOR ORTHOPYROXENES; REFLECTANCE SPECTRA; TELESCOPE FACILITY; MOSSBAUER-SPECTRA; ORDER-DISORDER; MINOR PLANETS AB Near-infrared (similar to 0.7 to similar to 2.5 mu m) spectra of S-asteroids 138 Tolosa, 306 Unitas, 346 Hermentaria, and 480 Hansa suggest the presence of variable amounts of orthopyroxene +/- clinopyroxene olivine +/- plagioclase feldspar on the surfaces of these asteroids. The spectra of these asteroids were compared to laboratory mineral mixtures of orthopyroxene, clinopyroxene, and olivine [Singer, R.B., 1981. J. Geophys. Res. 86 (139), 7967-7982; Cloutis, E.A., 1985. Master's thesis]. The band parameters (band centers, band areas) were quantified and temperature-corrected [Moroz et al., 2000. Icarus 147, 79-93; Gaffey et al., 2002. In: Bottke Jr., W.F., Cellino, A., Paolicchi, P., Binzel, R.P. (Eds.), Asteroids III. The University of Arizona Press, Tucson, pp. 183-2041. Each S-asteroid in this paper exhibits an overall spectral shape with band parameters that are inconsistent with ordinary chondrite near-infrared spectra and their inferred mineral abundances and/or pyroxene chemistries. 138 Tolosa displays a complex spectrum with a broad similar to 1 mu m absorption feature that displays a double Band I minimum, a well-defined absorption at similar to 1.3 mu m, and a broad, but weak absorption in the similar to 2 mu m region. Although different interpretations exist, the Tolosa spectrum is most consistent with a similar to 60/40 mixture of Type B clinopyroxene and orthopyroxene. Spectra of 306 Unitas suggest a surface with variable amounts of low-Ca pyroxene and olivine. Unitas is located in the S-(IV) and S-(VI) subtype regions in Gaffey et al. [1993. Icarus 106, 573-602]. 346 Hermentaria exhibits a complex, broad Band I absorption feature and a weak Band 11 feature, which suggests a similar to 50/50 mixture of clinopyroxene and orthopyroxene. Hermentaria is classified as an S-(111). Spectra of 480 Hansa suggest a dominant low-Ca pyroxene component with lesser amounts of olivine. Based on these characterizations, these four S-asteroids should not be considered as potential ordinary chondrite parent bodies. Furthermore, these results suggest that these S-asteroids experienced at least partial melting temperatures [T >= similar to 950 degrees C: Gaffey et al., 1993. Icarus 106, 573602; Keil, K., 2000. Planet. Space Sci. 48, 887-903] during the formation epoch in the early Solar System. Continuing spectroscopic investigations will discern the relative abundance of chondritic and thermally-evolved objects among the S-type asteroids that have survived since the formation epoch similar to 4.56 billion years ago. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ N Dakota, Dept Space Studies, Grand Forks, ND 58202 USA. Univ Winnipeg, Dept Geog, Winnipeg, MB R3B 2E9, Canada. NASA, Lyndon B Johnson Space Ctr, Planetary Astron Grp, Astromat Res & Explorat Sci, Houston, TX 77058 USA. RP Hardersen, PS (reprint author), Univ N Dakota, Dept Space Studies, Box 9008, Grand Forks, ND 58202 USA. EM hardersen@space.edu RI Hardersen, Paul/N-9343-2014; OI Hardersen, Paul/0000-0002-0440-9095; Reddy, Vishnu/0000-0002-7743-3491 NR 103 TC 18 Z9 18 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 0019-1035 J9 ICARUS JI Icarus PD MAR PY 2006 VL 181 IS 1 BP 94 EP 106 DI 10.1016/j.icarus.2005.10.003 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900006 ER PT J AU Busch, MW Ostro, SJ Benner, LAM Giorgim, JD Jurgens, RF Rose, R Magri, C Pravec, P Scheeres, DJ Broschart, SB AF Busch, MW Ostro, SJ Benner, LAM Giorgim, JD Jurgens, RF Rose, R Magri, C Pravec, P Scheeres, DJ Broschart, SB TI Radar and optical observations and physical modeling of near-Earth Asteroid 10115 (1992 SK) SO ICARUS LA English DT Article DE asteroids; radar; asteroids; rotation; surfaces; asteroids ID LIGHTCURVE INVERSION; OPTIMIZATION METHODS; SHAPE AB We estimate Asteroid 1992 SK's physical properties from delay-Doppler images and Doppler-only echo spectra obtained during March 22-27, 1999, at Goldstone and from optical lightcurves obtained during February-March 1999 at Ondrejov Observatory. The images span only about 15 degrees of sky motion and are not strong, but they place up to twenty 40 in by 160 m pixels on the asteroid and have complete rotational phase coverage. Our analysis establishes that the radar observations are confined to subradar latitudes between -20 degrees and -40 degrees. The echo spectra and optical lightcurves span similar to 80 degrees of sky motion, which provides important geometric leverage on the pole direction. The lightcurves are essential for accurate estimation of the asteroid's shape and spin state. We estimate the asteroid's period to be 7.3182 +/- 0.0003 h and its pole direction to be at ecliptic longitude, latitude = (99 degrees +/- 5 degrees, -3 degrees +/- 5 degrees). The asteroid is about 1.4 km in maximum extent and mildly asymmetric, with an elongation of about 1.5 and relatively subdued topography. The OC radar albedo is 0.11 +/- 0.02 and the SC/OC ratio is 0.34 +/- 0.05. The current orbital solution permits accurate identification of planetary close approaches during 826-2690. We use our model to predict salient characteristics of radar images and optical lightcurves obtainable during the asteroid's March 2006 approach. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Maine, Farmington, ME 04938 USA. Acad Sci Czech Republ, Astron Inst, CZ-25165 Ondrejov, Czech Republic. Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. RP Busch, MW (reprint author), CALTECH, Div Geol & Planetary Sci, Mail Code 150-21, Pasadena, CA 91125 USA. EM busch@caltech.edu RI Pravec, Petr/G-9037-2014 NR 11 TC 11 Z9 12 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 MAR PY 2006 VL 181 IS 1 BP 145 EP 155 DI 10.1016/j.icirus.2005.10.024 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900008 ER PT J AU Ciesla, FJ Cuzzi, JN AF Ciesla, FJ Cuzzi, JN TI The evolution of the water distribution in a viscous protoplanetary disk SO ICARUS LA English DT Article DE origin; solar system; solar nebula; meteorites; cosmochemistry; planetary formation ID DIFFERENTIALLY ROTATING-FLOWS; PRIMORDIAL SOLAR NEBULA; T-TAURI DISKS; ACCRETION DISKS; CARBONACEOUS CHONDRITES; REFRACTORY INCLUSIONS; LAYERED ACCRETION; SIZE DISTRIBUTION; SYSTEM; MODELS AB Astronomical observations have shown that protoplanetary disks are dynamic objects through which mass is transported and accreted by the central star. This transport causes the disks to decrease in mass and cool over time, and such evolution is expected to have occurred in our own solar nebula. Age dating of meteorite constituents shows that their creation, evolution, and accumulation occupied several Myr, and over this time disk properties would evolve significantly. Moreover, on this timescale, solid particles decouple from the gas in the disk and their evolution follows a different path. It is in this context that we must understand how our own solar nebula evolved and what effects this evolution had on the primitive materials contained within it. Here we present a model which tracks how the distribution of water changes in an evolving disk as the water-bearing species experience condensation, accretion, transport, collisional destruction, and vaporization. Because solids are transported in a disk at different rates depending on their sizes, the motions will lead to water being concentrated in some regions of a disk and depleted in others. These enhancements and depletions are consistent with the conditions needed to explain some aspects of the chemistry of chondritic meteorites and formation of giant planets. The levels of concentration and depletion, as well as their locations, depend strongly on the combined effects of the gaseous disk evolution, the formation of rapidly migrating rubble, and the growth of immobile planetesimals. Understanding how these processes operate simultaneously is critical to developing our models for meteorite parent body formation in the Solar System and giant planet formation throughout the galaxy. We present examples of evolution under a range of plausible assumptions and demonstrate how the chemical evolution of the inner region of a protoplanetary disk is intimately connected to the physical processes which occur in the outer regions. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, Mountain View, CA 94043 USA. RP Ciesla, FJ (reprint author), NASA, Ames Res Ctr, MS 245-3, Mountain View, CA 94043 USA. EM ciesla@cosmic.arc.nasa.gov NR 85 TC 167 Z9 167 U1 3 U2 19 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 MAR PY 2006 VL 181 IS 1 BP 178 EP 204 DI 10.1016/j.icarus.2005.11.009 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900011 ER PT J AU Burr, DM Emery, JP Lorenz, RD Collins, GC Carling, PA AF Burr, DM Emery, JP Lorenz, RD Collins, GC Carling, PA TI Sediment transport by liquid surficial flow: Application to Titan SO ICARUS LA English DT Article DE Titan; Mars; surface; surfaces; planets; satellites of Saturn; surfaces; satellite ID MARTIAN OUTFLOW CHANNELS; OPTICAL-CONSTANTS; TERMINAL VELOCITY; THRESHOLD CURVES; WATER FLOWS; SURFACE; ATMOSPHERE; CASSINI; ABUNDANCES; CURRENTS AB Sediment transport by surficial flow likely occurs on Titan. Titan is thought to have a volatile cycle, Such as on Earth and likely in the past on Mars, which would entail surficial liquid flow. And surficial flow is implied in interpretations of Cassini-Hyugens data as showing fluvial channels, which would require sediment transport by surficial flow to form the observable features. We present calculations from basic hydraulic formulae. of sediment entraimuent and transport by surficial flow. First, we describe the conditions for (non-cohesive) sediment entrainment by grain size through use of the Shields' threshold curve. We then calculate settling velocities by grain size to describe the type of sediment transport-washload, suspended load, or bedload-that would follow entrainment. These calculations allow derivation of required flow depths for sediment transport by grain size over a given slope. A technique to estimate required flow velocities and unit discharges is also presented. We show the results of these calculations for organic and water ice sediment movement by liquid methane flow under Titan gravity. For comparative purposes, plots for movement of quartz sediment by water on Earth and basalt sediment by water on Mars are also included. These results indicate that (non-cohesive) material would move more easily on Titan than on Earth or Mars. Terrestrial field observations suggest that coarse grain transport is enhanced by hyperconcentration of fine-grained sediment; and the apparent availability of organic (fine grained) sediment on Titan, in conjunction with the possibility of convection-driven rainstorms, may lead to hyperconcentrated flows. Thus, significant sediment transport may occur on Titan during individual overland flow events. (c) 2005 Elsevier Inc. All rights reserved. C1 SETI Inst, Mountain View, CA 94043 USA. NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Wheaton Coll, Dept Phys & Astron, Norton, MA 02766 USA. Highfield Univ Soutganotib, Sch Geochem, Southampton SO17 1BJ, Hants, England. RP Burr, DM (reprint author), SETI Inst, 515 N Whisman Rd, Mountain View, CA 94043 USA. EM dburr@seti.org RI Lorenz, Ralph/B-8759-2016 OI Lorenz, Ralph/0000-0001-8528-4644 NR 47 TC 50 Z9 50 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 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD MAR PY 2006 VL 181 IS 1 BP 235 EP 242 DI 10.1016/j.icarus.2005.11.012 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900015 ER PT J AU Teanby, NA Irwin, PGJ de Kok, R Nixon, CA Coustenis, A Bezard, B Calcutt, SB Bowles, NE Flasar, FM Fletcher, L Howett, C Taylor, FW AF Teanby, NA Irwin, PGJ de Kok, R Nixon, CA Coustenis, A Bezard, B Calcutt, SB Bowles, NE Flasar, FM Fletcher, L Howett, C Taylor, FW TI Latitudinal variations of HCN, HC3N, and C2N2 in Titan's stratosphere derived from cassini CIRS data SO ICARUS LA English DT Article DE Titan; atmospheres; composition ID ROTOTRANSLATIONAL ABSORPTION-SPECTRA; VOYAGER INFRARED OBSERVATIONS; MOLECULAR SPECTROSCOPIC DATABASE; HETERODYNE OBSERVATIONS; VERTICAL DISTRIBUTIONS; THERMAL EMISSION; ATMOSPHERE; PAIRS; TEMPERATURES; HITRAN AB Mid- and far-infrared spectra from the Composite InfraRed Spectrometer (CTRS) have been used to determine volume mixing ratios of nitriles in Titan's atmosphere. HCN, HC3N, C2H2, and temperature were derived from 2.5 cm(-1) spectral resolution mid-IR mapping sequences taken during three flybys, which provide almost complete global coverage of Titan for latitudes south of 60 degrees N. Three 0.5 cm(-1) spectral resolution far-IR observations were used to retrieve C2N2 and act as a check on the mid-IR results for HCN. Contribution functions peak at around 0.5-5 mbar for temperature and 0.1-10 mbar for the chemical species, well into the stratosphere. The retrieved mixing ratios of HCN, HC3N, and C2N2 show a marked increase in abundance towards the north, whereas C2H2 remains relatively constant. Variations with longitude were much smaller and are consistent with high zonal wind speeds. For 90 degrees-20 degrees S the retrieved HCN abundance is fairly constant with a volume mixing ratio of around 1 x 10(-7) at 3 mbar. More northerly latitudes indicate a steady increase, reaching around 4 x 10(-7) at 60 degrees N, where the data coverage stops. This variation is consistent with previous measurements and Suggests subsidence over the northern (winter) pole at approximately 2 x 10(-4) m s(-1). HC3N displays a very sharp increase towards the north pole, where it has a mixing ratio of around 4 x 10(-8) at 60 degrees N at the 0.1-mbar level. The difference in gradient for the HCN and HC3N latitude variations can be explained by HC3N's much shorter photochemical lifetime, which prevents it from mixing with air at lower latitude. It is also consistent with a polar vortex which inhibits mixing of volatile rich air inside the vortex with that at lower latitudes. Only one observation was far enough north to detect significant amounts of C2N2, giving a value of around 9 x 10(-10) at 50 degrees N at the 3-mbar level. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Observ Paris, Lab Etud Spatiales & Instrumentat Astrophys, F-92195 Meudon, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Teanby, NA (reprint author), Univ Oxford, Dept Phys, Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. EM teanby@atm.ox.ac.uk RI Fletcher, Leigh/D-6093-2011; Nixon, Conor/A-8531-2009; Flasar, F Michael/C-8509-2012; OI Fletcher, Leigh/0000-0001-5834-9588; Nixon, Conor/0000-0001-9540-9121; Calcutt, Simon/0000-0002-0102-3170; Teanby, Nicholas/0000-0003-3108-5775; Irwin, Patrick/0000-0002-6772-384X NR 52 TC 77 Z9 77 U1 0 U2 5 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 MAR PY 2006 VL 181 IS 1 BP 243 EP 255 DI 10.1016/j.icarus.2005.11.008 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900016 ER PT J AU Bernstein, MP Cruikshank, DP Sandford, SA AF Bernstein, MP Cruikshank, DP Sandford, SA TI Near-infrared spectra of laboratory H2O-CH4 ice mixtures S.2005.10.021 SO ICARUS LA English DT Article DE ices; infrared observations; spectroscopy; surfaces; planets; surfaces; satellites ID OPTICAL-CONSTANTS; PHYSICAL STATE; AMORPHOUS ICE; METHANE; ABSORPTION; TRITON; INTERSTELLAR; SPECTROSCOPY; SURFACE; SYSTEM AB We present 1.25-19 mu m infrared spectra of pure solid CH4 and H2O/CH4 = 87, 20, and 3 solid mixtures at temperatures from 15 to 150 K. We compare and contrast the absorptions of CH4 in solid H2O with those of pure CH4. Changes in selected peak positions, profiles, and relative strength with temperature are presented, and absolute strengths for absorptions of CH4 in solid H2O are estimated. Using the two largest (v(3) + v(4)) and (v(1) + v(4)) near-IR absorptions of CH4 at 2.324 and 2.377 mu m (4303 and 4207 cm(-1)), respectively, as examples, we show that peaks of CH4 in solid H2O are at slightly shorter wavelength (higher frequency) and broader than those of pure solid CH4. With increasing temperature, these peaks shift to higher frequency and become increasingly broad, but this trend is reversible on re-cooling, even though the phase transitions of H2O are irreversible. It is to be hoped that these observations of changes in the positions, profiles, and relative intensities of CH4 absorptions with concentration and temperature will be of use in understanding spectra of icy outer Solar System bodies. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Bernstein, MP (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. EM mbernstein@mail.arc.nasa.gov NR 24 TC 25 Z9 25 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 MAR PY 2006 VL 181 IS 1 BP 302 EP 308 DI 10.1016/j.icarus.2005.10.021 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900021 ER PT J AU Borderies-Rappaport, N Longaretti, PY AF Borderies-Rappaport, N Longaretti, PY TI Test particle motion around an oblate planet (vol 107, pg 129, 1994) SO ICARUS LA English DT Correction C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Observ Grenoble, F-38041 Grenoble, France. RP Borderies-Rappaport, N (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,301-150, Pasadena, CA 91109 USA. EM nicole.j.rappaport@jpl.nasa.gov; pyl@gag.observ-gr.ft NR 1 TC 0 Z9 0 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 0019-1035 J9 ICARUS JI Icarus PD MAR PY 2006 VL 181 IS 1 BP 326 EP 326 DI 10.1016/j.icarus.2005.09.006 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 022UP UT WOS:000236081900025 ER PT J AU Chapin, E Chen, CW AF Chapin, E Chen, CW TI GMTI along-track interferometry experiment SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Synthetic aperture radar (SAR) along track interferometry (ATI) has been used extensively to measure ocean surface currents. Given its ability to measure small velocities (similar to 10 cm/s) of relatively radar-dark water surfaces, there is great potential that this technique can be adapted for ground moving target indication (GMTI) applications, particularly as a method for detecting very slow targets with small radar cross-sections. In this paper we describe preliminary results from an ATI GMTI experiment. The SAR data described herein were collected by the dual-frequency NASA/JPL airborne radar in its standard dual-baseline ATI mode. The radar system imaged a variety of control targets including a pickup truck, sport utility vehicles, passenger cars, a bicycle, and pedestrians over multiple flight passes. The control targets had horizontal velocities of less than 5 m/s. The cross-sections of the targets were not purposely enhanced, although the targets' reflectivities may have been affected by the existence of the GPS equipment used to record the targets' positions. Single-look and multiple-look interferograms processed to the full azimuth resolution were analyzed. In the data processed to date, all of the targets were observed by visual inspection in at least one of the four combinations of dual-frequency, dual-baseline interferometric data. This extremely promising result demonstrates the potential of ATI for GMTI applications. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Chapin, E (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 6 TC 3 Z9 8 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD MAR PY 2006 VL 21 IS 3 BP 15 EP 20 DI 10.1109/MAES.2006.1624186 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 025BZ UT WOS:000236241600005 ER PT J AU Lee, DU Valees, EL Villasenor, JD Jones, CR AF Lee, DU Valees, EL Villasenor, JD Jones, CR TI Joint LDPC decoding and timing recovery using code constraint feedback SO IEEE COMMUNICATIONS LETTERS LA English DT Article DE low-density parity-check codes; symbol timing synchronization AB Timing recovery and channel decoding are traditionally performed independently. However, we show here that the information generated during the iterative decoding of Low-Density Parity-Check (LDPC) coded data can be fed back to the timing recovery circuit to enable accurate estimation of frequency and phase errors without the need for any pilot symbols. We describe a method capable of handling large offsets with complexity that grows linearly with offset size. Combining the LDPC constraint node observations with a properly calibrated phase locked loop allows successful tracking of a constant time delay, a frequency offset and a random phase walk. C1 Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lee, DU (reprint author), Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. EM dongu@icsl.ucal.edu; evalles@ee.ucla.edu; villa@icsl.ucla.edu; christop@jpl.nasa.gov NR 7 TC 10 Z9 10 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1089-7798 J9 IEEE COMMUN LETT JI IEEE Commun. Lett. PD MAR PY 2006 VL 10 IS 3 BP 189 EP 191 DI 10.1109/LCOMM.2006.03003 PG 3 WC Telecommunications SC Telecommunications GA 042RO UT WOS:000237547000021 ER PT J AU Dubovitsky, S Steier, WH AF Dubovitsky, S Steier, WH TI Relationship between the slowing and loss in optical delay lines SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE Fabry-Perot (FP) resonator; optical delay line ID MODULATORS; FILTERS AB In this paper, we demonstrate the relation between the amount of slowing and the amount of insertion loss in an optical slow wave structure when the material used has finite absorption. The delay properties are calculated as a function of wavelength for a single Fabry-Perot resonator and a delay line consisting of multiple coupled resonators. In all of these delay lines, if the amount of delay increases, the insertion loss of the line likewise increases. For low material loss, the normalized increase in delay is equal to the normalized increase in insertion loss. We also compare a coupled resonator delay line to a simple waveguide made of the same material and with the same amount of delay. The simple waveguide always has less insertion loss than the coupled resonator line because of the unavoidable reflection from the coupled resonator line. Even in the case of an asymmetric mirror delay line with zero reflection at the input, the simple waveguide has less insertion loss. C1 Univ So Calif, Dept Elect Engn, Los Angeles, CA 90089 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Dubovitsky, S (reprint author), Univ So Calif, Dept Elect Engn, Los Angeles, CA 90089 USA. EM dubovits@usc.edu; steier@usc.edu RI liu, ze/A-2322-2010 NR 6 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 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD MAR-APR PY 2006 VL 42 IS 3-4 BP 372 EP 377 DI 10.1109/JQE.2006.871551 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 030ZN UT WOS:000236674000019 ER PT J AU Le, T Savchenkov, AA Tazawa, H Steier, WH Maleki, L AF Le, T Savchenkov, AA Tazawa, H Steier, WH Maleki, L TI Polymer optical waveguide vertically coupled to high-Q whispering gallery resonators SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE integrated optics circuits; optical resonators; polymer waveguides; Q-factor; whispering gallery mode (WGM) resonators ID MICROCAVITY; FILTERS AB We report on a novel implementation of a polymer optical waveguide vertically coupled to the whispering gallery modes of a fused silica resonator disc. This is the first step in bringing high-Q silica discs close to the integrated optics technology. We obtained near-critical coupling and a loaded Q approximate to 3.4 x 10(6). C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ So Calif, Dept Elect Engn, Los Angeles, CA 90089 USA. RP Le, T (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM Thanh.M.Le@jpl.nasa.gov NR 13 TC 8 Z9 8 U1 1 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD MAR-APR PY 2006 VL 18 IS 5-8 BP 859 EP 861 DI 10.1109/LPT.2006.87181 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 035CL UT WOS:000236977500070 ER PT J AU Shapiro, AA Bonner, JK Ogunseitan, OA Saphores, JDM Schoenung, JM AF Shapiro, AA Bonner, JK Ogunseitan, OA Saphores, JDM Schoenung, JM TI Implications of Pb-free microelectronics assembly in aerospace applications SO IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES LA English DT Article DE aerospace industry; assembly; environmental testing; lead alloys; pollution; soldering; tin alloys ID LEAD; GASOLINE AB The commercial microelectronics industry is rapidly implementing Pb-free assembly strategies and it should be mostly Pb free within the next decade. This trend is driven by existing and proposed legislation in Europe and in Japan, which has already led a number of firms (including AT&T, IBM, Motorola, Hewlett-Packard, and Intel) to adopt Pb-free implementation programs. This is another sign that the microelectronics industry has become truly global. Following Moore's law, progress in microelectronics is brisk but not uniform: in many cases, commercial industry is ahead of the aerospace sector in technology. Progress by commercial industry, along with cost, drives the use of commercial off-the-shelf parts for military and space applications. We can thus anticipate that the U.S. aerospace industry, which is not subject to foreign legislation, will, at some point, be forced to use Pb-free components and subsystems as part of their standard business practices. In this, paper, we provide a snapshot of the commercial industry trends and how they may impact electronics in the aerospace environment. Impacts will be felt in the areas of reliability, assembly methods, cost drivers, supply chain selection, and alternative materials selection. In addition, we look at different strategies for implementation. The questions we address include the following: Should companies immediately embark on a program to convert all of their electronics to Ph free? Should they phase it in instead, and if so, over what time frame? Should companies try to comply with industry Pb-free standards? What requirements should flow down to subcontractors and component suppliers? Legislation is pending in a number of states that may affect these decisions and their timing. The U.S. Environmental Protection Agency, through some university programs, is examining the implementation of Ph free as well. Finally, we present data from a portion of a recent NASA project that focuses on finding suitable alternatives to eutectic Sn-Pb solders and solder pastes and on determining suitable processing operations in assembling printed wiring boards. The world is moving toward implementation of environmentally friendly manufacturing techniques. The aerospace industry will be forced to deal with issues related to Pb-free assembly, either because of the progressive scarcity of eutectic Sn-Pb solder or because of legislation. This paper provides insights into some of the key tradeoffs that should be considered. C1 CALTECH, Jet Prop Lab, Elect Packaging & Fabricat Sect, Pasadena, CA 91109 USA. Univ Calif Irvine, Dept Chem & Mat Sci, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Environm Hlth Sci & Policy, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Planning Policy & Design, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Econ, Irvine, CA 92697 USA. Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. RP Shapiro, AA (reprint author), CALTECH, Jet Prop Lab, Elect Packaging & Fabricat Sect, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM aashapiro@jpl.nasa.gov; oaogunse@uci.edu; saphores@uci.edu; jmschoenung@ucdavis.edu OI Ogunseitan, Oladele/0000-0003-1317-6219 NR 46 TC 7 Z9 7 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1521-3331 J9 IEEE T COMPON PACK T JI IEEE Trans. Compon. Packaging Technol. PD MAR PY 2006 VL 29 IS 1 BP 60 EP 70 DI 10.1109/TCAPT.2006 PG 11 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 020HW UT WOS:000235900500008 ER PT J AU Lu, B Wu, F Kim, S AF Lu, B Wu, F Kim, S TI Switching LPV control of an F-16 aircraft via controller state reset SO IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY LA English DT Article DE average dwell time; flight control; hysteresis switching; multiple parameter-dependent Lyapunov functions; switched linear parameter-varying systems; thrust vector ID HYBRID SYSTEMS; LYAPUNOV FUNCTIONS; VARYING SYSTEMS; FLIGHT CONTROL; STABILITY; DESIGN AB In flight control, the design objective and the aircraft dynamics may be different in low and high angle of attack regions. This paper presents a systematic switching LPV control design method to determine if it is practical to use for flight control designs over a wide angle of attack region. The approach is based on multiple parameter-dependent Lyapunov functions. A family of LPV controllers are designed, and each of them is suitable for a specific parameter subspace. The state of the controller is reset to guarantee the stability requirement of the Lyapunov function when the switching event occurs. Two parameter-dependent switching logics, hysteresis switching and switching with average dwell time, are examined. The proposed switching LPV control scheme is applied to an F-16 aircraft model with different design objectives and aircraft dynamics in low and high angle of attack regions. The nonlinear simulation results using both switching logics are compared. C1 Calif State Univ Long Beach, Dept Mech & Aerosp Engn, Long Beach, CA 90840 USA. NASA, Langley Res Ctr, Dynam Syst & Control Branch, Hampton, VA 23681 USA. RP Calif State Univ Long Beach, Dept Mech & Aerosp Engn, Long Beach, CA 90840 USA. EM blu3@csulb.edu; fwu@eos.ncsu.edu; s.kim@larc.nasa.gov RI KIM, SUNGWAN/E-4165-2012; Wu, Fen/H-5814-2012 OI Wu, Fen/0000-0001-8917-4557 NR 27 TC 132 Z9 150 U1 8 U2 28 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 MAR PY 2006 VL 14 IS 2 BP 267 EP 277 DI 10.1109/TCST.2005.863656 PG 11 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 018HH UT WOS:000235754500008 ER PT J AU Ruf, CS Hu, Y Brown, ST AF Ruf, CS Hu, Y Brown, ST TI Calibration of WindSat polarimetric channels with a vicarious cold reference SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE calibration; microwave radiometry ID MICROWAVE RADIOMETER; DIELECTRIC-CONSTANT; VECTOR; WATER AB Absolute calibration of WindSat's third and fourth Stokes brightness temperatures (T-3 and T-4) is needed at the tenth of Kelvin level in order to adequately resolve their dependence on wind direction. Previous aircraft based fully polarimetric microwave radiometers have generally relied on "circle flights" during which a single area of the ocean is observed at all azimuth angles, to estimate residual biases in the calibration of its polarimetric channels. WindSat, the first spaceborne fully polarimetric microwave radiometer, operates in low earth orbit and thus cannot execute this traditional calibration technique. A new method is presented to estimate the residual biases that are present in WindSat's T3 and T4 estimates. The method uses a vicarious cold reference brightness temperature applied to measurements made by WindSat at +/- 45 degrees slant linear (T-P and T-M) and left- and right-hand circular (T-L and T-R) polarization. WindSat derives the third and fourth Stokes brightness temperatures by the differences T-P - T-M and T-L - T-R, respectively. The method is demonstrated by applying it to the 10.7-GHz WindSat observations. Calibration biases of 0.2-0.6 K are determined with a precision of 0.04 K. C1 Univ Michigan, Space Phys Res Lab, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. CALTECH, Jet Prop Lab, Microwoave Adv Syst, Pasadena, CA 91109 USA. RP Ruf, CS (reprint author), Univ Michigan, Space Phys Res Lab, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. EM cruf@umich.edu; ihu@isr.umich.edu; shannon.t.brown@jpl.nasa.gov RI Ruf, Christopher/I-9463-2012 NR 15 TC 7 Z9 8 U1 1 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 MAR PY 2006 VL 44 IS 3 BP 470 EP 475 DI 10.1109/TGRS.2005.855996 PG 6 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 018ST UT WOS:000235785800002 ER PT J AU Yueh, SH Wilson, WJ Dinardo, SJ Hsiao, SV AF Yueh, SH Wilson, WJ Dinardo, SJ Hsiao, SV TI Polarimetric microwave wind radiometer model function and retrieval testing for WindSat SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE ocean surface wind; polarimetric radiometer; scatterometer; tropical cycloned ID SURFACE BRIGHTNESS TEMPERATURES; AIRCRAFT K-BAND; DIRECTION; SCATTEROMETER; SIGNATURES AB A geophysical model function (GMF), relating the directional response of polarimetric brightness temperatures to ocean surface winds, is developed for the WindSat multifrequency polarimetric microwave radiometer. This GMF is derived from the WindSat data and tuned with the aircraft radiometer measurements for very high winds from the Hurricane Ocean Wind Experiment in 1997. The directional signals in the aircraft polarimetric radiometer data are corroborated by coincident Ku-band scatterometer measurements for wind speeds in the range of 20-35 m/s. We applied an iterative retrieval algorithm using the polarimetric brightness temperatures from 18-, 23-, and 37-GHz channels. We find that the root-mean-square direction difference between the Global Data Assimilation System winds and the closest WindSat wind ambiguity is less than 20 degrees for above 7-m/s wind speed. The retrieval analysis supports the consistency of the Windrad05 GMF with the WindSat data. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yueh, SH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM simon.yueh@jpl.nasa.gov NR 23 TC 25 Z9 32 U1 1 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 MAR PY 2006 VL 44 IS 3 BP 584 EP 596 DI 10.1109/TGRS.2005.858416 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 018ST UT WOS:000235785800012 ER PT J AU Brown, ST Ruf, CS Lyzenga, DR AF Brown, ST Ruf, CS Lyzenga, DR TI An emissivity-based wind vector retrieval algorithm for the WindSat polarimetric radiometer SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE polarimetry; sea surface emissivity; wind vector; WindSat ID SURFACE BRIGHTNESS TEMPERATURES; SEA-SURFACE; MODEL AB The Naval Research Laboratory WindSat polarimetric radiometer was launched on January 6, 2003 and is the first fully polarimetric radiometer to be flown in space. WindSat has three fully polarimetric channels at 10.7, 18.7, and 37.0 GHz and vertically and horizontally polarized channels at 6.8 and 23.8 GHz. A first-generation wind vector retrieval algorithm for the WindSat polarimetric radiometer is developed in this study. An atmospheric clearing algorithm is used to estimate the surface emissivity from the measured WindSat brightness temperature at each channel. A specular correction factor is introduced in the radiative transfer equation to account for excess reflected atmospheric brightness, compared to the specular assumption, as a function wind speed. An empirical geophysical model function relating the surface emissivity to the wind vector is derived using coincident QuikSCAT scatterometer wind vector measurements. The confidence in the derived harmonics for the polarimetric channels is high and should be considered suitable to validate analytical surface scattering models for polarized ocean surface emission. The performance of the retrieval algorithm is assessed with comparisons to Global Data Assimilation System (GDAS) wind vector outputs. The root mean square (RMS) uncertainty of the closest wind direction ambiguity is less than 20 degrees for wind speeds greater than 6 m/s and less than 15 degrees at 10 m/s and greater. The retrieval skill, the percentage of retrievals in which the first-rank solution is the closest to the GDAS reference, is 75% at 7 m/s and 85% or higher above 10 m/s. The wind speed is retrieved with an RMS uncertainty of 1.5 m/s. C1 CALTECH, Jet Prop Lab, Microwave Adv Syst, Pasadena, CA 91109 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Space Phys Res Lab, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Naval Architecture & Marine Engn, Ann Arbor, MI 48109 USA. RP Brown, ST (reprint author), CALTECH, Jet Prop Lab, Microwave Adv Syst, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM shannon.t.brown@jpl.nasa.gov RI Ruf, Christopher/I-9463-2012 NR 22 TC 18 Z9 20 U1 2 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 MAR PY 2006 VL 44 IS 3 BP 611 EP 621 DI 10.1109/TGRS.2005.859351 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 018ST UT WOS:000235785800014 ER PT J AU Epp, LW Hoppe, DJ Kelley, DT AF Epp, LW Hoppe, DJ Kelley, DT TI A TE/TM modal solution for rectangular hard waveguides SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE characteristic equation; hard rectangular waveguide; longitudinally corrugated waveguide; modal solution ID ASYMPTOTIC BOUNDARY-CONDITIONS; HORN ANTENNAS; SURFACES; SOFT AB A TE/TM modal solution for a longitudinally corrugated rectangular waveguide is developed. These longitudinal corrugations can be used to excite a quasi-TEM wave and form a hard waveguide by correctly choosing the impedance at the guide wall. The correctly chosen impedance is referred to as the hard boundary condition. The modal solution developed here solves the problem of longitudinal corrugations filled with a dielectric material by first finding and solving the characteristic equation for a complete TE/TM modal set. It is shown that this TE/TM mode solution can be used to achieve the hard boundary condition resulting in the quasi-TEM wave in a hard waveguide for discrete values of corrugation depth. Beyond each of these depths, a mode becomes a surface wave. The theoretical mode set is amenable to the solution of problems using the mode-matching method. A combination of the mode-matching method and the TE/TM modal solution will allow the solution of larger problems. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Honeywell Technol Solut Inc, Columbia, MD 21046 USA. RP Epp, LW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Larry.Epp@jpl.nasa.gov; Daniel.Hoppe@jpl.nasa.gov; dkelley@gdscc.nasa.gov NR 18 TC 5 Z9 5 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD MAR PY 2006 VL 54 IS 3 BP 1048 EP 1054 DI 10.1109/TMTT.2005.864135 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 022UL UT WOS:000236081500008 ER PT J AU U-Yen, K Wollack, EJ Doiron, TA Papapolymerou, J Laskar, J AF U-Yen, K Wollack, EJ Doiron, TA Papapolymerou, J Laskar, J TI A planar bandpass filter design with wide stopband using double split-end stepped-impedance resonators SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE microstrip; microwave filter; spurious response; stepped-impedance resonator (SIR); transmission zero ID SUPPRESSION AB In this paper, we propose a compact planar bandpass filter design with wide stopband. The double split-end quarter-wave-length (lambda/4) resonator is introduced to reduce the resonator size while providing additional transmission zeros. Optimal split-end length is determined to provide transmission zeros that attenuate the two lowest spurious resonance frequencies. The singly loaded quality factor (Q(si)) of the optimal-length lambda/4 stepped-impedance resonator (SIR) is also analytically derived. Using the proposed technique to design an Nth-order filter, N + 1 controllable transmission zeros are generated and used to suppress spurious frequency responses. The experimental design shows that the sixth-order filter can provide a very broad stopband of 8.5 times the fundamental frequency with at least 37.8 dB of attenuation using the SIRs with a stepped-impedance ratio (R) of 0.528. C1 NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA USA. RP U-Yen, K (reprint author), NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM kuyen@pop500.gsfc.nasa.gov; papapol@ece.gatech.edu RI Wollack, Edward/D-4467-2012 OI Wollack, Edward/0000-0002-7567-4451 NR 13 TC 25 Z9 25 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD MAR PY 2006 VL 54 IS 3 BP 1237 EP 1244 DI 10.1109/TMTT.2005.864098 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA 022UL UT WOS:000236081500031 ER PT J AU Cho, J Principe, JC Erdogmus, D Motter, MA AF Cho, J Principe, JC Erdogmus, D Motter, MA TI Modeling and inverse controller design for an unmanned aerial vehicle based on the self-organizing map SO IEEE TRANSACTIONS ON NEURAL NETWORKS LA English DT Article DE inverse controller; local linear model; multiple models; self-organizing map (SOM) ID TIME-SERIES; SYSTEMS; IDENTIFICATION AB The next generation of aircraft will have dynamics that vary considerably over the operating regime. A single controller will have difficulty to meet the design specifications. In this paper, a self-organizing map (SOM)-based local linear modeling scheme of an unmanned aerial vehicle (UAV) is developed to design a set of inverse controllers. The SOM selects the operating regime depending only on the embedded output space information and avoids normalization of the input data. Each local linear model is associated with a linear controller, which is easy to design. Switching of the controllers is done synchronously with the active local linear model that tracks the different operating conditions. The proposed multiple modeling and control strategy has been successfully tested in a simulator that models the LoFLYTE UAV. C1 Univ Florida, Computat NeuroEngn Lab, Gainesville, FL 32611 USA. Oregon Hlth Sci Univ, Dept Comp Sci & Elect Engn, Beaverton, OR 97006 USA. NASA, Langley Res Ctr, Elect Syst Branch, Hampton, VA 23681 USA. RP Cho, J (reprint author), Univ Florida, Computat NeuroEngn Lab, Gainesville, FL 32611 USA. EM jeongho@cnel.ufl.edu; principe@cnel.ufl.edu; derdogmus@ieee.org; m.a.motter@larc.nasa.gov RI Erdogmus, Deniz/A-8170-2009 NR 42 TC 31 Z9 34 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1045-9227 J9 IEEE T NEURAL NETWOR JI IEEE Trans. Neural Netw. PD MAR PY 2006 VL 17 IS 2 BP 445 EP 460 DI 10.1109/TNN.2005.863422 PG 16 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 026SD UT WOS:000236361500014 PM 16566471 ER PT J AU Sundaresan, A Singh, K Pellis, NR DuMond, J AF Sundaresan (Lalita), Alamelu Singh, Kamleshwar Pellis, Neal R. DuMond, James TI Signal transduction targets of modeled microgravity. SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Meeting Abstract C1 Texas So Univ, Houston, TX 77004 USA. NASA, Lyndon B Johnson Space Ctr, Human Res Program, Houston, TX 77058 USA. EM sundaresana@TSU.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOCIETY IN VITRO BIOLOGY PI RALEIGH PA 514 DANIELS STREET, STE 411, RALEIGH, NC 27605 USA SN 1071-2690 J9 IN VITRO CELL DEV-AN JI In Vitro Cell. Dev. Biol.-Anim. PD SPR PY 2006 VL 42 SU S BP 27A EP 27A PG 1 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 106VF UT WOS:000242129400097 ER PT J AU Scoffield, J Egnin, M Bey, B Quain, M Prakash, CS Mortley, D AF Scoffield, J. Egnin, M. Bey, B. Quain, M. Prakash, C. S. Mortley, D. TI Development of an efficient Agrobacterium-mediated gene transfer system for multiple sweetpotato cultivars. SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Meeting Abstract C1 Tuskegee Univ, NASA, Plant Biotechnol & Genom Res Lab, Tuskegee, AL 36088 USA. EM megnin@tuskegee.edu NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOCIETY IN VITRO BIOLOGY PI RALEIGH PA 514 DANIELS STREET, STE 411, RALEIGH, NC 27605 USA SN 1071-2690 J9 IN VITRO CELL DEV-AN JI In Vitro Cell. Dev. Biol.-Anim. PD SPR PY 2006 VL 42 SU S BP 36A EP 36A PG 1 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 106VF UT WOS:000242129400128 ER PT J AU Bey, B Egnin, M Scoffield, J Williams, AS Mortley, D Crawford, LS Quain, M AF Bey, B. Egnin, M. Scoffield, J. Williams, A. S. Mortley, D. Crawford, L. S. Quain, M. TI Development of efficient in vitro systems for peanut (Arachis hypogaea L.) micropropagation and seed production. SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Meeting Abstract C1 Tuskegee Univ, NASA, Plant Biotechnol & Genom Res Lab, Tuskegee, AL 36088 USA. Alabama A&M Univ, Dept Plant & Soil Sci, Normal, AL 35762 USA. EM megnin@tuskegee.edu NR 0 TC 0 Z9 0 U1 0 U2 3 PU SOCIETY IN VITRO BIOLOGY PI RALEIGH PA 514 DANIELS STREET, STE 411, RALEIGH, NC 27605 USA SN 1071-2690 J9 IN VITRO CELL DEV-AN JI In Vitro Cell. Dev. Biol.-Anim. PD SPR PY 2006 VL 42 SU S BP 44A EP 44A PG 1 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 106VF UT WOS:000242129400157 ER PT J AU Sarkar, S Wise, KC Manna, SK Ramesh, V Yamauchi, K Thomas, RL Wilson, BL Kulkarni, AD Pellis, NR Ramesh, GT AF Sarkar, Shubhashish Wise, Kimberly C. Manna, Sunil K. Ramesh, Vani Yamauchi, Keiko Thomas, Renard L. Wilson, Bobby L. Kulkarni, Anil D. Pellis, Neil. R. Ramesh, Govindarajan. T. TI Activation of activator protein-1 in mouse brain regions exposed to simulated microgravity SO IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL LA English DT Article DE simulated microgravity; hindlimb unloading; activator protein-1 ID FACTOR-KAPPA-B; AP-1; RATS; WEIGHTLESSNESS; ENVIRONMENT; EXPRESSION AB Microgravity induces stress, and the brain is one of the targets that is more influenced in this environment. Alteration in transcription factors can have enormous effect because of discrepancy in the signaling process of the cells. Activator protein-1 (AP-1) is a stress-regulated transcription factor and is involved in the regulation of physiological and pathological stimuli that include cytokines, growth factors, and stress signals. In the present study, an attempt has been made to observe the effect of a microgravity environment on the activation of AP-1 in the mouse brain. Our results show that AP-1 transcription factor is activated in simulated microgravity conditions in different regions of the brain. The activation of the AP-1 is dependent upon the increased kinase activity of c-Jun NH-terminal(2), kinase-1. These results suggest that microgravity stress in the brain can elicit AP-1 activity. C1 Texas So Univ, Dept Biol, Mol Neurotoxicol Lab Proteom Core, Houston, TX 77004 USA. Univ Texas, Dept Surg, Houston, TX 77030 USA. Ctr DNA Fingerprinting & Diagnost, Immunol Lab, Hyderabad 500076, Andhra Pradesh, India. NASA, Lyndon B Johnson Space Ctr, Cellular Biotechnol Program, Houston, TX 77058 USA. RP Ramesh, GT (reprint author), Texas So Univ, Dept Biol, Mol Neurotoxicol Lab Proteom Core, 3100 Cleburne Ave, Houston, TX 77004 USA. EM ramesh_gt@tsu.edu FU NCRR NIH HHS [G12 RR003045, RR03045-19, G12 RR003045-190001] NR 20 TC 3 Z9 3 U1 0 U2 2 PU SOC IN VITRO BIOLOGY PI LARGO PA 9315 LARGO DR WEST, STE 25, LARGO, MD 20774 USA SN 1071-2690 J9 IN VITRO CELL DEV-AN JI In Vitro Cell. Dev. Biol.-Anim. PD MAR-APR PY 2006 VL 42 IS 3-4 BP 96 EP 99 PG 4 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 094NE UT WOS:000241245300009 PM 16759155 ER PT J AU Ruiz-Torres, AJ Zapata, E Cowen, ML AF Ruiz-Torres, Alex J. Zapata, Edgar Cowen, Marcella L. TI Modeling of turnaround operations for next generation space transportation architectures SO INTERNATIONAL JOURNAL OF INDUSTRIAL ENGINEERING-THEORY APPLICATIONS AND PRACTICE LA English DT Article DE operations modeling; space vehicles; design assessment; cost assessment; knowledge based modeling AB This paper presents an approach to space transportation turnaround operations modeling using knowledge based complexity functions. This project is of significant relevance to the field of industrial engineering as it deals with knowledge based estimation of processing operations based on the design characteristics of an extremely complex product. The modeling approach uses expert's knowledge to predict the ground cycle time and costs of a new concept launch vehicle by functions that estimate the complexity and reliability of the system based on its design characteristics. The operational requirements include the interactions between the launch vehicle and its ground infrastructure: the spaceport. Finally, the paper discusses the implementation of the modeling concept into a tool called Architecture Assessment Tool - enhanced (AATe) used by NASA and its contractors. Significance: It is imperative that space transportation systems be analyzed in the very earliest of design to ensure all life cycle costs are considered. This paper presents an approach to the operational cost and time modeling of these systems by knowledge based complexity functions and the importance of this assessment using the concept of total design. C1 Univ Texas, Coll Business Adm, El Paso, TX 79968 USA. NASA, Syst Engn, Kennedy Space Ctr, FL 32899 USA. Blue Frog Technol, El Paso, TX 79902 USA. RP Ruiz-Torres, AJ (reprint author), Univ Texas, Coll Business Adm, El Paso, TX 79968 USA. OI Ruiz-Torres, Alex/0000-0002-7528-236X NR 9 TC 0 Z9 0 U1 0 U2 1 PU UNIV CINCINNATI INDUSTRIAL ENGINEERING PI CINCINNATI PA UNIV CINCINNATI, CINCINNATI, OH 45221-0116 USA SN 1072-4761 J9 INT J IND ENG-THEORY JI Int. J. Ind. Eng.-Theory Appl. Pract. PD MAR PY 2006 VL 13 IS 1 BP 18 EP 27 PG 10 WC Engineering, Industrial; Engineering, Manufacturing SC Engineering GA 170AZ UT WOS:000246634700002 ER PT J AU Oterkus, E Barut, A Madenci, E Smeltzer, SS Ambur, DR AF Oterkus, E Barut, A Madenci, E Smeltzer, SS Ambur, DR TI Bonded lap joints of composite laminates with tapered edges SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE bonded; lap joints; nonlinear; laminates ID GEOMETRICALLY NONLINEAR-ANALYSIS; VISCOPLASTICITY; ADHESIVES AB This study presents a semi-analytical solution method to analyze the geometrically nonlinear response of bonded composite lap joints with tapered and/or non tapered adherend edges under uniaxial tension. The solution method provides the transverse shear and normal stresses in the adhesives and in-plane stress resultants and bending moments in the adherends. The method utilizes the principle of virtual work in conjunction with von Karman's nonlinear plate theory to model the adherends and the shear lag model to represent the kinematics of the thin adhesive layers between the adherends. Furthermore, the method accounts for the bilinear elastic material behavior of the adhesive while maintaining a linear stress-strain relationship in the adherends. In order to account for the stiffness changes due to thickness variation of the adherends along the tapered edges, the in-plane and bending stiffness matrices of the adherents are varied as a function of thickness along the tapered region. The combination of these complexities results in a system of nonlinear governing equilibrium equations. This approach represents a computationally efficient alternative to finite element method. The numerical results present the effects of taper angle, adherend overlap length, and the bilinear adhesive material on the stress fields in the adherends, as well as the adhesives of a single- and double-lap joint. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Arizona, Dept Aeronaut & Mech Engn, Tucson, AZ 85721 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Madenci, E (reprint author), Univ Arizona, Dept Aeronaut & Mech Engn, 1130 N Mt Ave, Tucson, AZ 85721 USA. EM madenci@email.arizona.edu NR 15 TC 19 Z9 20 U1 1 U2 6 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 MAR PY 2006 VL 43 IS 6 BP 1459 EP 1489 DI 10.1016/j.ijsolstr.2005.07.035 PG 31 WC Mechanics SC Mechanics GA 015SA UT WOS:000235570000007 ER PT J AU Starks, SA Kosheleva, O Kreinovich, V AF Starks, Scott A. Kosheleva, Olga Kreinovich, Vladik TI Kaluza-Klein 5D ideas made fully geometric SO INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS LA English DT Article DE 5D geometry; Kaluza-Klein theory; compactification of extra dimensions; Einstein-Bergman approach to 5D models AB After the 1916 success of general relativity that explained gravity by adding time as a fourth dimension, physicists have been trying to explain other physical fields by adding extra dimensions. In 1921, Kaluza and Klein has shown that under certain conditions like cylindricity (partial derivative g (ij) /partial derivative x(5) = 0), the addition of the 5th dimension can explain the electromagnetic field. The problem with this approach is that while the model itself is geometric, conditions like cylindricity are not geometric. This problem was partly solved by Einstein and Bergman who proposed, in their 1938 paper, that the 5th dimension is compactified into a small circle S-1 so that in the resulting cylindric 5D space-time R-4 x S-1 the dependence on x(5) is not macroscopically noticeable. We show that if, in all definitions of vectors, tensors, etc., we replace R-4 with R-4 x S-1, then conditions like cylindricity automatically follow - i.e., these conditions become fully geometric. C1 Univ Texas, NASA, PanAmer Ctr Earth & Environm Studies, El Paso, TX 79968 USA. RP Starks, SA (reprint author), Univ Texas, NASA, PanAmer Ctr Earth & Environm Studies, El Paso, TX 79968 USA. EM sstarks@utep.edu; oglak@utep.edu; vladik@utep.edu NR 12 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0020-7748 J9 INT J THEOR PHYS JI Int. J. Theor. Phys. PD MAR PY 2006 VL 45 IS 3 BP 589 EP 601 DI 10.1007/s10773-006-9047-x PG 13 WC Physics, Multidisciplinary SC Physics GA 061CC UT WOS:000238847800011 ER PT J AU Johnson, L James, B Baggett, R Montgomery, EE AF Johnson, L James, B Baggett, R Montgomery, EE TI NASA's in-space propulsion technology program: A step toward interstellar exploration SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article; Proceedings Paper CT 4th IAA Symposium on Realistic Near-Term Advanced Scientific Space Missions CY JUL 04-06, 2005 CL Aosta, ITALY SP Int Acad Austronaut DE aerocapture; electric propulsion; solar sails; interstellar propulsion AB NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space. The maximum theoretical efficiencies have almost been reached and are insufficient to meet needs for many ambitious science missions currently being considered. By developing the capability to Support mid-term robotic mission needs, the program is laying the technological foundation for travel to nearby interstellar space. The In-Space Propulsion Technology Program's technology portfolio includes many advanced propulsion systems. From the next-generation ion propulsion systems operating in the 5-10 kW range, to solar sail propulsion, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called "propellantless" because they do not require onboard fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails and aerocapture. This paper will provide an overview of those propellantless and propel I ant-based advanced propulsion technologies that will most significantly advance our exploration of deep space. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Johnson, L (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM Charles.L.Johnson-1@nasa.gov RI Yin, Yimei/G-7749-2012 NR 12 TC 1 Z9 1 U1 0 U2 11 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD MAR-APR PY 2006 VL 59 IS 3-4 BP 99 EP 103 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 020DR UT WOS:000235889100004 ER PT J AU Rossow, VJ AF Rossow, VJ TI Classical wing theory and the downward velocity of vortex wakes SO JOURNAL OF AIRCRAFT LA English DT Article AB Classical wing theory is extended downstream from a flat vortex sheet to include vortex-wake configurations that can be considered as fully rolled up into a vortex pair. Classical wing theory was chosen as the method to be used because it is based on the flux of downward momentum imparted to the ambient flow field by the lift on a wing. After the theory is reviewed to establish the theoretical process used to analyze vortex wakes, it is extended to the configuration of lift-generated wakes that occur after roll-up of the vortex sheet, and that are composed of a vortex pair inside of an oval-shaped region that propagates downward as a unit. The distribution of downward momentum inside the oval, and in the surrounding fluid, found for the rolled-up vortex pair is then applied to vortex wakes as they undergo instabilities that lead to their decomposition and dispersion. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Rossow, VJ (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 12 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 MAR-APR PY 2006 VL 43 IS 2 BP 381 EP 385 DI 10.2514/1.15203 PG 5 WC Engineering, Aerospace SC Engineering GA 036LD UT WOS:000237071700009 ER PT J AU Owens, DB Bryant, EM Barlow, JB AF Owens, DB Bryant, EM Barlow, JB TI Free-to-roll investigation of the preproduction F/A-18E powered-approach wing drop SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 43rd Aerospace Sciences Meeting and Exhibit CY JAN 10-13, 2005 CL Reno, NV SP AIAA AB A free-to-roll study of the low-speed lateral characteristics of the preproduction F/A-18E was conducted in the NASA Langley 12-Foot Low-Speed Tunnel. In developmental flight tests the F/A-18E unexpectedly experienced uncommanded lateral motions in the power-approach configuration. The objective of this study was to determine the feasibility of using the free-to-roll technique for the detection of uncommanded lateral motions for the preproduction F/A-18E in the power-approach configuration. The data revealed that this technique in conjunction with static data revealed insight into the cause of the lateral motions. The free-to-roll technique identified uncommanded lateral motions at the same angle-of-attack range as experienced in flight tests. The cause of the uncommanded lateral motions was unsteady asymmetric wing stall. The paper also shows that free-to-roll data or static force and moment data alone are not enough to accurately predict and characterize uncommanded lateral motion. C1 NASA, Langley Res Ctr, Flight Dynam Branch, Hampton, VA 23681 USA. Univ Maryland, USAF, College Pk, MD 20742 USA. RP Owens, DB (reprint author), NASA, Langley Res Ctr, Flight Dynam Branch, Hampton, VA 23681 USA. NR 6 TC 0 Z9 0 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 MAR-APR PY 2006 VL 43 IS 2 BP 466 EP 470 DI 10.2514/1.15721 PG 5 WC Engineering, Aerospace SC Engineering GA 036LD UT WOS:000237071700020 ER PT J AU Baker, DJ AF Baker, DJ TI Response of damaged and undamaged tailored extension-shear-coupled composite panels SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 44th Structures, Structural Dynamics and Materials Conference CY APR 07-10, 2003 CL Norfolk, VA SP AIAA, ASME, ASCE, AHS, ASC AB The results of an analytical and experimental investigation of the response of composite I-stiffener panels with extension-shear coupling are presented. This tailored concept, when used in the panel cover skins of a tiltrotor aircraft wing, has the potential for increasing the aeroelastic stability margins and improving the aircraft productivity. The extension-shear coupling is achieved by using unbalanced +/- 45-deg plies in the skin. Experimental and STAGS analysis results are compared for eight I-stiffener panel specimens. The results indicate that the tailored concept would be feasible to use in the wing skin of a tiltrotor aircraft. Evaluation of specimens impacted at an energy level of 500 in.-lb indicate a minimal loss in stiffness and less than 30% loss in strength. Evaluation of specimens with severed center stiffener and adjacent skin indicated a strength loss in excess of 60%. C1 NASA, Langley Res Ctr, Mech & Durabil Branch, Vehicle Technol Directorate ARL, Hampton, VA 23681 USA. RP Baker, DJ (reprint author), NASA, Langley Res Ctr, Mech & Durabil Branch, Vehicle Technol Directorate ARL, Hampton, VA 23681 USA. NR 6 TC 4 Z9 5 U1 0 U2 1 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 MAR-APR PY 2006 VL 43 IS 2 BP 517 EP 527 DI 10.2514/1.9856 PG 11 WC Engineering, Aerospace SC Engineering GA 036LD UT WOS:000237071700025 ER PT J AU Grecu, M Olson, WS AF Grecu, M Olson, WS TI Bayesian estimation of precipitation from satellite passive microwave observations using combined radar-radiometer retrievals SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article ID RAINFALL MEASURING MISSION; SOUTH CHINA SEA; PART I; ALGORITHM; PROFILES; TRMM; SYSTEMS; HEAT AB Precipitation estimation from satellite passive microwave radiometer observations is a problem that does not have a unique solution that is insensitive to errors in the input data. Traditionally, to make this problem well posed, a priori information derived from physical models or independent, high-quality observations is incorporated into the solution. In the present study, a database of precipitation profiles and associated brightness temperatures is constructed to serve as a priori information in a passive microwave radiometer algorithm. The precipitation profiles are derived from a Tropical Rainfall Measuring Mission (TRMM) combined radar-radiometer algorithm, and the brightness temperatures are TRMM Microwave Imager (TMI) observed. Because the observed brightness temperatures are consistent with those derived from a radiative transfer model embedded in the combined algorithm, the precipitation-brightness temperature database is considered to be physically consistent. The database examined here is derived from the analysis of a month-long record of TRMM data that yields more than a million profiles of precipitation and associated brightness temperatures. These profiles arc clustered into a tractable number of classes based on the local sea surface temperature, a radiometer-based estimate of the echo-top height (the height beyond which the reflectivity drops below 17 dBZ), and brightness temperature principal components. For each class, the mean precipitation profile, brightness temperature principal components, and probability of occurrence are determined. The precipitation-brightness temperature database supports a radiometer-only algorithm that incorporates a Bayesian estimation methodology. In the Bayesian framework, precipitation estimates are weighted averages of the mean precipitation values corresponding to the classes in the database, with the weights being determined according to the similarity between the observed brightness temperature principal components and the brightness temperature principal components of the classes. Because the classes are stratified by the sea surface - temperature and the echo-top-height estimator, the number of classes that are considered for retrieval is significantly smaller than the total number of classes, making the algorithm computationally efficient. The radiometer-only algorithm is applied to TMI observations, and precipitation estimates are compared with combined TRMM precipitation radar (PR)-TMI reference estimates. The TMI-only algorithm, supported by the empirically derived database, produces estimates that are more consistent with the reference values than the precipitation estimates from the version-6 TRMM facility TMI algorithm. Cloud-resolving model simulations are used to assign a latent heating profile to each precipitation profile in the empirically derived database, making it possible to estimate latent heating using the radiometer-only algorithm. Although the evaluation of latent heating estimates in this study is preliminary, because realistic conditional probability distribution functions are attached to latent heating structures in the algorithm's database, a generally positive impact oil latent heating estimation from passive microwave observations is expected. C1 NASA, GEST, UMBC, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. RP Grecu, M (reprint author), NASA, GEST, UMBC, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA. EM grecu@agnes.gsfc.nasa.gov NR 25 TC 41 Z9 42 U1 0 U2 3 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 MAR PY 2006 VL 45 IS 3 BP 416 EP 433 DI 10.1175/JAM2360.1 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 039EY UT WOS:000237290000004 ER PT J AU Hinghofer-Szalkay, HG Rossler, A Evans, JM Stenger, MB Moore, FB Knapp, CF AF Hinghofer-Szalkay, HG Rossler, A Evans, JM Stenger, MB Moore, FB Knapp, CF TI Circulatory galanin levels increase severalfold with intense orthostatic challenge in healthy humans SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE blood pressure stability; syncope; hormones; gender differences ID HEAD-UP TILT; PLASMA-RENIN CONCENTRATION; BED REST; VASOPRESSIN; HYPOTENSION; TOLERANCE; SECRETION; MEN; ACTIVATION; RESPONSES AB The purpose of this study was to test the hypothesis that plasma galanin concentration (pGal) is regularly increased in healthy humans with extensive orthostatic stress. Twenty-six test persons (14 men, 12 women) were brought to an orthostatic end point via a progressive cardiovascular stress (PCS) protocol consisting of 70 head-up tilt plus increasing levels of lower body negative pressure until either hemodynamically defined presyncope or other signs of orthostatic intolerance occurred ( nausea, clammy skin, excessive sweating, pallor of the skin). We further tested for possible gender, gravitational, and muscular training influences on plasma pGal responses: PCS was applied before and after 3 wk of daily vertical acceleration exposure training on a Human Powered Centrifuge. Test persons were randomly assigned to active (with bicycle work) or passive (without work) groups (seven men, six women in each group). Resting pGal was 26 +/- 3 pg/ ml in men and 39 +/- 15 pg/ ml in women (not significant); women had higher galanin responses (4.9- fold increase) than men (3.5-fold, P = 0.017) to PCS exposure. Overall, PCS increased pGal to 186 +/- 5 pg/ ml (P = 0.0003), without significant differences between presyncope vs. orthostatic intolerance, pre- vs. postcentrifuge, or active vs. passive gravitational training. Increases in pGal were poorly related to synchronous elevations in plasma vasopressin. We conclude that galanin is regularly increased in healthy humans under conditions of presyncopal orthostatic stress, the response being independent of gravity training but larger in women than in men. C1 Med Univ, Inst Physiol, Ctr Physiol Med, A-8010 Graz, Austria. Med Univ, Inst Adapt & Spaceflight Physiol, A-8010 Graz, Austria. Univ Kentucky, Ctr Biomed Engn, Lexington, KY 40506 USA. NASA, Ames Ctr Biol & Gravitat Res, Moffett Field, CA USA. RP Hinghofer-Szalkay, HG (reprint author), Med Univ, Inst Physiol, Ctr Physiol Med, Harrachgasse 21, A-8010 Graz, Austria. EM helmut.hinghofer@meduni-graz.at RI Roessler, Andreas/A-5751-2008 FU NCRR NIH HHS [M01 RR-00827] NR 36 TC 13 Z9 13 U1 0 U2 2 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD MAR PY 2006 VL 100 IS 3 BP 844 EP 849 DI 10.1152/japplphysiol.01039.2005 PG 6 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 010QW UT WOS:000235210200014 PM 16322373 ER PT J AU Bigbee, AJ Grindeland, RE Roy, RR Zhong, H Gosselink, KL Arnaud, S Edgerton, VR AF Bigbee, AJ Grindeland, RE Roy, RR Zhong, H Gosselink, KL Arnaud, S Edgerton, VR TI Basal and evoked levels of bioassayable growth hormone are altered by hindlimb unloading SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE spaceflight; central nervous system; activity-dependence; proprioception; plasma hormones ID RAT PITUITARY; PLASMA CONSTITUENTS; CELL-FUNCTION; MUSCLE; SPACEFLIGHT; RELEASE; MICROGRAVITY; SUSPENSION; RADIOIMMUNOASSAY; ADAPTATIONS AB Bioassayable growth hormone (BGH) in rats is released in large quantities from the pituitary in response to the activation of large, proprioceptive afferent fibers from fast and mixed fiber-type hindlimb musculature. We hypothesized that hindlimb unloading (HU) of adult male rats would 1) reduce the basal levels of plasma BGH, and 2) abolish stimulusinduced BGH release. Rats were exposed to HU for 1, 4, or 8 wk. Plasma and pituitaries were collected under isoflurane anesthesia for hormone analyses. Additionally, at 4 and 8 wk, a subset of rats underwent an in situ electrical stimulation (Stim) of tibial nerve proprioceptive afferents. Basal plasma BGH levels were significantly reduced (-51 and -23%) after 1 and 8 wk of HU compared with ambulatory controls (Amb). Although Amb-Stim rats exhibited increased plasma BGH levels ( 88 and 143%) and decreased pituitary BGH levels (-27 and -22%) at 4 and 8 wk, respectively, stimulation in HU rats had the opposite effect, reducing plasma BGH (-25 and -33%) and increasing pituitary BGH levels (47 and 10%) relative to HU alone at 4 and 8 wk. The 22-kDa form of GH measured by immunoassay and the plasma corticosterone, T3, T4, and testosterone levels were unchanged by HU or Stim at all time points. These data suggest that BGH synthesis and release from the pituitary are sensitive both to chronically reduced neuromuscular loading and to acute changes in neuromuscular activation, independent of changes in other circulating hormones. Thus BGH may play a role in muscle, bone, and metabolic adaptations that occur in response to chronically unloaded states. C1 Univ Calif Los Angeles, Dept Neurobiol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Physiol Sci, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Brain Res Inst, Los Angeles, CA 90095 USA. NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. RP Roy, RR (reprint author), Univ Calif Los Angeles, Dept Neurobiol, 1804 Life Sci Bldg,621 Charles E Young Dr, Los Angeles, CA 90095 USA. EM rrr@ucla.edu FU NIDCR NIH HHS [DE-N0489] NR 32 TC 6 Z9 7 U1 0 U2 1 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD MAR PY 2006 VL 100 IS 3 BP 1037 EP 1042 DI 10.1152/japplphysiol.00615.2005 PG 6 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 010QW UT WOS:000235210200038 PM 16339349 ER PT J AU Heymsfield, AJ Schmitt, C Bansemer, A van Zadelhoff, GJ McGill, MRJ Twohy, C Baumgardner, D AF Heymsfield, AJ Schmitt, C Bansemer, A van Zadelhoff, GJ McGill, MRJ Twohy, C Baumgardner, D TI Effective radius of ice cloud particle populations derived from aircraft probes SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID COUNTERFLOW VIRTUAL IMPACTOR; CIRRUS CLOUDS; WATER-CONTENT; PARAMETERIZATION; SIZE; MICROPHYSICS; TEMPERATURE AB The effective radius (r(e)) is a crucial variable in representing the radiative properties of cloud layers in general circulation models. This parameter is proportional to the condensed water content (CWC) divided by the extinction (sigma). For ice cloud layers, parameterizations for r(e) have been developed from aircraft in situ measurements 1) indirectly. using data obtained from particle spectrometer probes and assumptions or observations about particle shape and mass to get the ice water content (IWC) and area to get sigma and recently 2) from probes that derive IWC and sigma more directly. referred to as the direct approach, even though the extinction is not measured directly. This study compares [IWC/sigma] derived from the two methods using datasets acquired from comparable instruments on two aircraft. one sampling Clouds at midlevels and the other at upper levels during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers (CRYSTAL) Florida Area Cirrus Experiment (FACE) field program in Florida in 2002. A penetration by one of the aircraft into a cold midlatitude orographic wave cloud composed of small particles is further evaluated. The sigma and IWC derived by each method are compared and evaluated in different ways for each aircraft dataset. Direct measurements of sigma exceed those derived indirectly by a factor of 2-2.5. The IWC probes, relying on ice sublimation, appear to measure accurately except when the IWC is high or the particles too large to sublimate completely during the short transit time through the probe. The IWC estimated from the particle probes are accurate when direct measurements are available to provide constraints and give useful information in high IWC/large particle situations. Because of the discrepancy in sigma estimates between the direct and indirect approaches. there is a factor of 2-3 difference in [IWC/sigma] between them. Although there tire significant uncertainties involved in its use. comparisons with several independent data sources suggest that the indirect method is the more accurate of the two approaches. However. experiments are needed to resolve the source of the discrepancy in sigma. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Koninklijk Nederlands Meteorol Inst, De Bilt, Netherlands. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. Univ Nacl Autonoma Mexico, Ctr Ciencias Atmosfera, Mexico City 04510, DF, Mexico. RP Heymsfield, AJ (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM heyms1@ncar.ucar.edu RI Heymsfield, Andrew/E-7340-2011; van Zadelhoff, Gerd-Jan/K-6283-2013; Schmitt, Carl/P-5490-2015; OI Schmitt, Carl/0000-0003-3829-6970 NR 26 TC 28 Z9 28 U1 0 U2 7 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 MAR PY 2006 VL 23 IS 3 BP 361 EP 380 DI 10.1175/JTECH1857.1 PG 20 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 034DW UT WOS:000236908500003 ER PT J AU Denton, RE Goldsten, J Lee, DH King, RA Dent, ZC Gallagher, DL Berube, D Takahashi, K Nose, M Milling, D Honary, F AF Denton, RE Goldsten, J Lee, DH King, RA Dent, ZC Gallagher, DL Berube, D Takahashi, K Nose, M Milling, D Honary, F TI Realistic magnetospheric density model for 29 August 2000 SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article DE plasmasphere; density model; mass density; electron density; IMAGE EUV; field line resonance mode ID EXTREME-ULTRAVIOLET IMAGER; GEOMAGNETIC-FIELD LINES; ELECTRON-DENSITY; MAGNETOMETER NETWORK; ART.; PLASMAPAUSE; PLASMASPHERE; EIGENFREQUENCIES; FREQUENCIES; RESONANCES AB Using a two dimensional image of the Earth's plasmasphere taken by the Extreme Ultraviolet Imager (EUV) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft, in-situ electron density measurements from the IMAGE Radio Plasma Imager (RPI) instrument, measurements of magnetospheric mass density inferred from field line resonant frequencies measured by magnetometers on the Earth's surface, and a model for the density field aligned variation, we construct a computer model for the magnetospheric density on 29 August 2000 at 1519 UT. The purposes of this study are to demonstrate how a density model can be constructed using multiple data sources, to document this particular model, which is being used in studies of ultra low frequency Pi-2 oscillations and plasmaspheric cavity modes, to describe some of the problems involved with EUV density inversion, and to demonstrate some features of the plasmaspheric density, particularly in the region of the dusk plasmatrough and plume. (c) 2005 Elsevier Ltd. All rights reserved. C1 Dartmouth Coll, Dept Phys & Astron, Wilder Lab 6127, Hanover, NH 03755 USA. SW Res Inst, Space Sci & Engn Div 15, San Antonio, TX 78238 USA. Kyung Hee Univ, Dept Astron & Space Sci, Yongin 449701, Kyunggi Do, South Korea. Univ Arizona, Tucson, AZ 85721 USA. Univ Alberta, Dept Phys, Space Phys Grp, Edmonton, AB T6G 2J1, Canada. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35803 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Kyoto Univ, Data Anal Ctr Geomagnetism & Space, Sakyo Ku, Kyoto 6068502, Japan. Univ Lancaster, Dept Commun Syst, Lancaster LA1 4YR, England. RP Denton, RE (reprint author), Dartmouth Coll, Dept Phys & Astron, Wilder Lab 6127, Hanover, NH 03755 USA. EM richard.c.denton@dartmouth.edu RI Nose, Masahito/B-1900-2015 OI Nose, Masahito/0000-0002-2789-3588 NR 37 TC 8 Z9 8 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 EI 1879-1824 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD MAR PY 2006 VL 68 IS 6 BP 615 EP 628 DI 10.1016/j.jastp.2005.11.009 PG 14 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 027RB UT WOS:000236431800002 ER PT J AU Liu, Y Vinokur, M Wang, ZJ AF Liu, Y Vinokur, M Wang, ZJ TI Spectral (finite) volume method for conservation laws on unstructured grids V: Extension to three-dimensional systems SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE high-order; unstructured grid; spectral volume; 3D systems of conservation laws; Maxwell equations ID ESSENTIALLY NONOSCILLATORY SCHEMES; ONE-DIMENSIONAL SYSTEMS; ELEMENT METHOD; IMPLEMENTATION; EQUATIONS; MESHES AB In this paper, the fifth in a series, the high-order spectral finite-volume, or spectral volume (SV) method for unstructured grids is extended to three dimensions. Limitations of conventional structured and unstructured methods are first reviewed. The spectral finite-volume method for generalized conservation laws is then described. It is shown that if all grid cells are partitioned into structured sub-cells in a similar manner, the discretizations become universal, and are reduced to the same weighted sum of unknowns involving just a few simple adds and multiplies. Important aspects of the data structure and its effects on communication and the optimum use of cache memory are discussed. Previously defined one-parameter partitions of the SV in 2D are extended to multiple parameters and then used to construct 3D partitions. Numerical solutions of plane electromagnetic waves incident on perfectly conducting circular cylinders and spheres are presented and compared with the exact solution to demonstrate the capability of the method. Excellent agreement has been found. Computation timings show that the new method is more efficient than conventional structured and unstructured methods. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Eloret Corp, Sunnyvale, CA 94087 USA. Iowa State Univ Sci & Technol, Dept Aerosp Engn, Ames, IA 50011 USA. RP Liu, Y (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM yen.liu@nasa.gov RI Wang, Z.J./A-9628-2010 OI Wang, Z.J./0000-0002-6203-6303 NR 28 TC 67 Z9 68 U1 1 U2 8 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 MAR 1 PY 2006 VL 212 IS 2 BP 454 EP 472 DI 10.1016/j.jcp.2005.06.024 PG 19 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 995QY UT WOS:000234120100005 ER PT J AU McCown, R Gross, FB Calle, CI AF McCown, R Gross, FB Calle, CI TI Medium velocity impact triboelectrification experiments with JSC Mars-1 regolith simulant SO JOURNAL OF ELECTROSTATICS LA English DT Article DE triboelectric charging; saltation; shakerbox; regolith ID PARTICLE-CHARGING EXPERIMENTS AB As land-based robotic missions to Mars have increased in scope and mobility, NASA has intensified its research efforts involving the mechanisms of electrostatic charging oil the surface of Mars. The primary concern is that electrostatic adhesion and discharge might interfere with the operation of sensitive components, or interfere with communications and control systems. A secondary effect might be the electrostatic build-up of dust oil solar panels, reducing mission effectiveness. One goal of this research is to assist in the development of electrostatic mitigation, including the selection of materials that resist excessive charging when placed in frictional contact with the Martian regolith.(1) However, most information related to frictional charging, or triboelectrification, is of an empirical nature. Based oil experimentation, some materials have historically been arranged into triboelectric series in which the magnitude and sign of charge acquired through frictional contact can be predicted with reasonable accuracy. However, Martian regolith is not a homogeneous substance, so the approach of the traditional triboelectic series cannot be easily applied. Furthermore, an adequate theory that fully explains triboelectrification does not yet exist. For these reasons, it is necessary to empirically determine the materials and environmental conditions in which frictional charging oil Mars becomes significant. Therefore, an experimental procedure has been developed for determining some triboelectric charging characteristics of JSC MARS-1 regolith simulant, based on a shaker box concept Suggested by Dr. Carlos Calle of the Materials Research Laboratory at Kennedy Space Center. Over 300 trials under specific test conditions have been performed using this test procedure, with materials common to NASA project equipment used in space exploration. Test results indicate that moderately successful control over test conditions has been achieved, but the acquired electrostatic charge of the regolith simulant did not follow expected trends for all test materials. An analysis of time dependence trials conducted during this study indicates that at least two distinct, identifiable charging mechanisms affected magnitude and sign of the cumulative charge. The first is triboelectrification between the simulant and the test material. The second is inter-particle charging of the regolith simulant, with Subsequent transfer between the test material and simulant. With some test materials these differing mechanisms yielded opposing charge polarities, in that the resulting magnitude of the acquired charge appears to be the difference, not the sum of the charging processes. (c) 2005 Elsevier B.V. All rights reserved. C1 Florida State Univ, Coll Engn, Dept Elect & Comp Engn, FAMU, Tallahassee, FL 32310 USA. NASA, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA. RP Gross, FB (reprint author), Florida State Univ, Coll Engn, Dept Elect & Comp Engn, FAMU, Tallahassee, FL 32310 USA. EM frank.gross@argonst.com NR 5 TC 8 Z9 8 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3886 J9 J ELECTROSTAT JI J. Electrost. PD MAR PY 2006 VL 64 IS 3-4 BP 187 EP 193 DI 10.1016/j.elstat.2005.05.007 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 012HT UT WOS:000235329900003 ER PT J AU Montgomery, JF Johnson, AE Roumelliotis, SI Matthies, LH AF Montgomery, James F. Johnson, Andrew E. Roumelliotis, Stergios I. Matthies, Larry H. TI The jet propulsion laboratory autonomous helicopter testbed: A platform for planetary exploration technology research and development SO JOURNAL OF FIELD ROBOTICS LA English DT Article ID MOTION; VEHICLE AB The Jet Propulsion Laboratory Autonomous Helicopter Testbed (AHT), an aerial robot based upon a radio-controlled model helicopter, provides a small low-cost platform for developing and field testing new technologies needed for future space missions. The AHT helps cover the test space in a complementary fashion to other methods, such as rocket sleds or parachute drops. The AHT design and implementation is presented as well as experimental results and milestones achieved since its creation in 2001. In addition, technologies we are developing and testing are described. These include image-based hazard detection and avoidance algorithms for safe landing in dangerous terrain and an extended Kalman filter that augments inertial navigation with image-based motion estimates to enable pin-point landing. (c) 2006 Wiley Periodicals, Inc. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Minnesota, Dept Comp Sci & Engn, Minneapolis, MN 55455 USA. RP Montgomery, JF (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM monty@jpl.nasa.gov; aej@jpl.nasa.gov; stergios@cs.umn.edu; lhm@jpl.nasa.gov NR 37 TC 19 Z9 21 U1 0 U2 1 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 1556-4959 J9 J FIELD ROBOT JI J. Field Robot. PD MAR-APR PY 2006 VL 23 IS 3-4 BP 245 EP 267 DI 10.1002/rob.20110 PG 23 WC Robotics SC Robotics GA 163GF UT WOS:000246146200006 ER PT J AU Russell, RP Ocampo, CA AF Russell, RP Ocampo, CA TI Optimization of a broad class of ephemeris model earth-mars cyclers SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID TRAJECTORIES AB Recent interest in cycler trajectories has led to the discovery of many new solutions. Most, however, are valid only in a circular-coplanar solar system. The current study presents a method to optimize accurate model cyclers based on simple model solutions and catalogs the results for a broad class of ephemeris model Earth-Mars cyclers. An efficient constrained optimization problem is defined to accommodate long-duration, ballistic, patched conic trajectories. A continuation algorithm is then developed to transition infinitely continuous circular-coplanar solutions to finite-duration accurate ephemeris solutions. Finally, the algorithm is applied to 203 promising circular-coplanar parent cyclers for 21 launch windows each, equaling 4263 cases. In total, there are nine parent cyclers (one of them is the well-known Aldrin cycler) that have at least one finite-duration cycler with a total maneuver requirement of less than 1 m/s over seven full cycles. Additionally, 39 and 74 parent cyclers have at least one launch date with a maneuver requirement of less than 10 and 300 m/s, respectively. Several of the most promising cyclers have consistently low requirements for all launch windows considered. In general, the study demonstrates the broad feasibility for accurate ephemeris cyclers. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Texas, Austin, TX 78712 USA. RP Russell, RP (reprint author), CALTECH, Jet Prop Lab, M-S 301-140L,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Ryan.Russell@jpl.nasa.gov NR 33 TC 8 Z9 8 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 MAR-APR PY 2006 VL 29 IS 2 BP 354 EP 367 DI 10.2514/1.13652 PG 14 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 022MJ UT WOS:000236059600013 ER PT J AU Kukreja, SL Brenner, MJ AF Kukreja, SL Brenner, MJ TI Nonlinear aeroelastic system identification with application to experimental data SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID NON-LINEAR SYSTEMS; OUTPUT PARAMETRIC MODELS; NONPARAMETRIC IDENTIFICATION; INCOMPRESSIBLE-FLOW; VALIDITY TESTS; NARMAX MODELS; FIGHTER; FLUTTER; AIRFOIL; SET AB Representation and identification of a nonlinear aeroelastic pitch-plunge system as a model of the NARMAX class is considered. A nonlinear difference equation describing this aircraft model is derived theoretically and shown to be of the NARMAX form. Identification methods for NARMAX models are applied to aeroelastic dynamics and their properties demonstrated via continuous-time simulations of experimental conditions. Simulation results show that 1) the outputs of the NARMAX model closely match those generated using continuous-time methods and 2) NARMAX identification methods applied to aeroelastic dynamics provide accurate discrete-time parameter estimates. Application of NARMAX identification to experimental pitch-plunge dynamics data gives a high percent fit for cross-validated data. C1 NASA, Dryden Flight Res Ctr, Natl Res Council, Struct Dynam Grp,Aerosp Branch, Edwards AFB, CA 93523 USA. RP Kukreja, SL (reprint author), NASA, Dryden Flight Res Ctr, Natl Res Council, Struct Dynam Grp,Aerosp Branch, MailStop 4840, Edwards AFB, CA 93523 USA. EM sunil.kukreja@nasa.gov NR 42 TC 5 Z9 7 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 MAR-APR PY 2006 VL 29 IS 2 BP 374 EP 381 DI 10.2514/1.15178 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 022MJ UT WOS:000236059600015 ER PT J AU Brugarolas, PB Bayard, DS Spanos, JT Breckenridge, WG AF Brugarolas, PB Bayard, DS Spanos, JT Breckenridge, WG TI System identification of a nonlinear mode for the shuttle radar topography mission SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 05-08, 2002 CL MONTEREY, CA SP Amer Inst Aeronaut & Astronaut AB A study is presented to identify a nonlinear bending mode for a 60-m space structure. This study was done in support of the Shuttle Radar Topography Mission (SRTM) and postflight height reconstruction efforts. For this purpose, one linear model and three nonlinear models of the structural mode were considered and evaluated. The best model was determined based on in-flight data collected during the mission and was implemented as part of the final ground software that was used for reconstructing relative radar antenna motion for the SRTM interferometer payload. High accuracy estimates of the relative states were essential for supporting the motion compensation algorithm used in the radar interferometry processor for calculating the desired topographic maps. The improvement resulting from identifying nonlinear modal behavior contributed to meeting mission performance requirements. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 90012 USA. RP Brugarolas, PB (reprint author), CALTECH, Jet Propuls Lab, Pasadena, CA 90012 USA. EM paul.b.brugarolas@jpl.nasa.gov; david.s.bayard@jpl.nasa.gov; john.t.spanos@jpl.nasa.gov; william.g.breckenridge@jpl.nasa.gov NR 7 TC 1 Z9 3 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 MAR-APR PY 2006 VL 29 IS 2 BP 421 EP 426 DI 10.2514/1.6989 PG 6 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 022MJ UT WOS:000236059600020 ER PT J AU Yu, CH Saha, S Zhou, JH Shi, L Cassell, AM Cruden, BA Ngo, Q Li, J AF Yu, CH Saha, S Zhou, JH Shi, L Cassell, AM Cruden, BA Ngo, Q Li, J TI Thermal contact resistance and thermal conductivity of a carbon nanofiber SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE contact resistance; nanofiber; thermal conductivity; uncertainty analysis; platinum coating; nanoscale contact; thermal constriction resistance; phonon scattering AB We have measured the thermal resistance of a 152-nm-diameter carbon nanofiber before and after a platinum layer was deposited on the contacts between the nanofiber and the measurement device. The contact resistance was reduced by the platinum coating for about 9-13% of the total thermal resistance of the nanofiber sample before the platinum coating. At a temperature of 300 K, the axial thermal conductivity of the carbon nanofiber is about three times smaller than that of graphite fibers grown by pyrolysis of natural gas prior to high-temperature heat treatment, and increases with temperature in the temperature range between 150 K and 310 K. The phonon mean free path was found to be about 1.5 nm and approximately temperature-independent. This feature and the absence of a peak in the thermal conductivity curve indicate that phonon-boundary and phonon-defect scattering dominate over phonon-phonon Umklapp scattering for the temperature range. C1 Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. Univ Texas, Ctr nano & Mol Sci & Technol, Texas Mat Inst, Austin, TX 78712 USA. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Shi, L (reprint author), Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. EM lishi@mail.utexas.edu RI Shi, Li/C-8123-2013; Li, Jun/H-7771-2013 OI Shi, Li/0000-0002-5401-6839; Li, Jun/0000-0002-3689-8946 NR 22 TC 102 Z9 103 U1 5 U2 34 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 EI 1528-8943 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAR PY 2006 VL 128 IS 3 BP 234 EP 239 DI 10.1115/1.2150833 PG 6 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 021TV UT WOS:000236009600003 ER PT J AU Odegard, GM Gates, TS AF Odegard, GM Gates, TS TI Modeling and testing of the viscoelastic properties of a graphite nanoplatelet/epoxy composite SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES LA English DT Article DE dynamical mechanical analysis; micromechanics; modeling; nanoindentation; nanotechnology ID INTERCALATION POLYMERIZATION AB To facilitate the interpretation of experimental data, a micromechanical modeling procedure is developed to predict the viscoelastic properties of a graphite nanoplatelet/epoxy composite as a function of volume fraction and nanoplatelet diameter. The storage and loss moduli predicted for the composite are compared to values measured from the same material using three test methods: dynamical mechanical analysis, nanoindentation, and quasi-static tensile tests. In most cases, the model and experiments indicate that for increasing volume fractions of nanoplatelets, both the storage and the loss moduli increase. In addition, the results indicate that for nanoplatelet sizes above 15 mu m, nanoindentation is capable of measuring properties of individual constituents of a composite system. A comparison of the values predicted to the data measured helps to illustrate the relative similarities and differences between the bulk and the local measurement techniques. C1 Michigan Technol Univ, Dept Mech Engn Engn Mech, Houghton, MI 49931 USA. NASA Langley Res Ctr, Mech Struct & Mat Branch, Hampton, VA 23681 USA. RP Odegard, GM (reprint author), Michigan Technol Univ, Dept Mech Engn Engn Mech, 1400 Townsend Dr, Houghton, MI 49931 USA. EM gmodegar@mtu.edu NR 21 TC 15 Z9 15 U1 1 U2 11 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 1045-389X J9 J INTEL MAT SYST STR JI J. Intell. Mater. Syst. Struct. PD MAR PY 2006 VL 17 IS 3 BP 239 EP 246 DI 10.1177/1045389X06057523 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 023EK UT WOS:000236108300007 ER PT J AU Flaten, JA Lindensmith, CA Zimmermann, W AF Flaten, J. A. Lindensmith, C. A. Zimmermann, W., Jr. TI The frequency dependence of critical-velocity behavior in the oscillatory flow of superfluid (4)He through a 2 x 2-mu m aperture in a thin foil SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE superfluid (4)He; aperture flow; critical velocity; phase slip; large-energy-loss events; dissipation ID QUANTUM VORTEX MOTION; MU-M APERTURE; PHASE-SLIP; HELIUM; NUCLEATION; VORTICES; AVALANCHES; ORIFICE AB The critical-velocity behavior of oscillatory superfluid (4)He flow through a 2 x 2-mu m aperture in a 0.1-mu m-thick metal foil has been studied from 0.36 to 2.10 K at frequencies from less than 50 Hz up to above 1880 Hz. The pressure remained less than 0.5 bar. In early runs during which the frequency remained below 400 Hz, the critical velocity was a nearly-linearly decreasing function of increasing temperature throughout the region of temperature studied. In runs at the lowest frequencies, isolated 2 pi phase slips could be observed at the onset of dissipation. In runs with frequencies higher than 400 Hz, downward curvature was observed in the decrease of critical velocity with increasing temperature. In addition, above 500 Hz an alteration in supercritical behavior was seen at the lower temperatures, involving the appearance of large-energy-loss events. These irregular events typically lasted a few tens of half-cycles of oscillation and could involve hundreds of times more energy loss than would have occurred in a single complete 2 pi phase slip at maximum flow. The temperatures at which this altered behavior was observed rose with frequency, from similar to 0.6 K and below at 500 Hz, to similar to 1.0 K and below at 1880 Hz. C1 Luther Coll, Dept Phys, Decorah, IA 52101 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Minnesota, Tate Lab Phys, Minneapolis, MN 55455 USA. RP Flaten, JA (reprint author), Luther Coll, Dept Phys, Decorah, IA 52101 USA. EM zimme004@umn.edu NR 36 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAR PY 2006 VL 142 IS 5-6 BP 725 EP 752 DI 10.1007/s10909-006-9205-9 PG 28 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 097NK UT WOS:000241454500002 ER PT J AU Flaten, JA Borden, CT Lindensmith, CA Zimmermann, W AF Flaten, J. A. Borden, C. T. Lindensmith, C. A. Zimmermann, W., Jr. TI Simulations of vortex evolution and phase slip in oscillatory potential flow of the superfluid component of (4)He through an aperture SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE Superfluid (4)He; oscillatory aperture flow; phase slip; vortices; simulation; oblate-spheroidal flow ID CRITICAL VELOCITY; HELIUM; DYNAMICS; ORIFICE; FREQUENCIES; VORTICES; EQUATION; MOTION AB The evolution of semicircular quantum vortex loops in oscillating potential flow emerging from an aperture is simulated in some highly symmetrical cases. As the frequency of potential flow oscillation increases, vortex loops that are evolving so as eventually to cross all of the streamlines of potential flow are drawn back toward the aperture when the flow reverses. As a result, the escape size of the vortex loops, and hence the net energy transferred from potential flow to vortex flow in such 2 pi phase-slip events, decreases as the oscillation frequency increases. Above some aperture-dependent and flow-dependent threshold frequency, vortex loops are drawn back into the aperture. Simulations are performed using both radial potential flow and oblate-spheroidal potential flow. C1 Luther Coll, Dept Phys, Decorah, IA 52101 USA. Michigan Technol Univ, Houghton, MI 49931 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Minnesota, Phys Lab, Minneapolis, MN 55455 USA. RP Flaten, JA (reprint author), Luther Coll, Dept Phys, Decorah, IA 52101 USA. EM zimme004@umn.edu NR 36 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAR PY 2006 VL 142 IS 5-6 BP 753 EP 767 DI 10.1007/s10909-006-9206-8 PG 15 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 097NK UT WOS:000241454500003 ER PT J AU Hull, PV Canfield, S AF Hull, PV Canfield, S TI Optimal synthesis of compliant mechanisms using subdivision and commercial FEA SO JOURNAL OF MECHANICAL DESIGN LA English DT Article ID SHAPE OPTIMIZATION; GENETIC ALGORITHMS; TOPOLOGY DESIGN; SURFACES AB The field of distributed-compliance mechanisms has seen significant work in developing suitable topology optimization tools,for their design. These optimal design tools have grown out of the techniques of structural optimization. This paper will build oil the previous work in topology optimization and compliant mechanism design by proposing an alternative design space parametrization through control points and adding another step to the process, that of subdivision. The control points allow a specific design to be represented as a solid model during the optimization process. The process of subdivision creates an additional number of control points that help smooth the surface (for example a C-2 continuous surface depending on the method of subdivision chosen) creating a manifacturable design free of some traditional numerical instabilities. Note that these additional control points do not add to the number of design parameters. This alternative parametrization and description as a solid model effectively and completely separates the design variables from the analysis variables during the optimization procedure. The motivation behind this work is to create an automated design tool from task definition to functional prototype created on a CNC or rapid-prototype machine. This paper will describe the proposed compliant mechanism design process and will demonstrate the procedure on several examples common in the literature. C1 NASA, George C Marshall Space Flight Ctr, Engn Directorate, Huntsville, AL 35812 USA. Tennessee Technol Univ, Dept Mech Engn, Cookeville, TN 38505 USA. RP Hull, PV (reprint author), NASA, George C Marshall Space Flight Ctr, Engn Directorate, Huntsville, AL 35812 USA. EM scanfield@tntech.edu NR 31 TC 23 Z9 26 U1 0 U2 6 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1050-0472 J9 J MECH DESIGN JI J. Mech. Des. PD MAR PY 2006 VL 128 IS 2 BP 337 EP 348 DI 10.1115/1.2159026 PG 12 WC Engineering, Mechanical SC Engineering GA 022LU UT WOS:000236058100002 ER PT J AU Drouin, BJ Miller, CE Fry, JL Petkie, DT Helminger, P Medvedev, IR AF Drouin, BJ Miller, CE Fry, JL Petkie, DT Helminger, P Medvedev, IR TI Submillimeter measurements of isotopes of nitric acid SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE nitric acid; rotational spectroscopy; submillimeter ID MICROWAVE-SPECTRUM; ROTATIONAL SPECTROSCOPY; INFRARED-SPECTRUM; LINE POSITIONS; DNO3; MILLIMETER; BANDS; HNO3; INTENSITIES AB The ground and low-lying vibrational states of nitric acid are observable with current instrumentation in the Earth's thermal submillimeter atmospheric emission. Remote sensing continues to improve to higher sensitivity and future missions will allow these measurements with minimal integration time. Sensing of weaker spectral features will require signal averaging, and choices of spectral windows for these features will require knowledge of the higher vibrational states and rare isotopes of the strongly emitting species. Nearly comprehensive information on vibrational states and isotopically substituted species is now available from wide bandwidth scans of natural and isotopically enriched nitric acid. In this work, ground state rotational spectra of five isotopically substituted species of nitric acid are analyzed in the submillimeter spectral range. We present the Hamiltonian parameters necessary for prediction and identification of isotopic features across the nitric acid ground state rotational spectrum. (C) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Arthur Amos Noyes Lab Chem Phys, Pasadena, CA 91125 USA. Wright State Univ, Dept Phys, Dayton, OH 45435 USA. Univ S Alabama, Dept Phys, Mobile, AL 36688 USA. Ohio State Univ, Dept Phys, Columbus, OH 43210 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 RI Medvedev, Ivan/E-8486-2014 NR 21 TC 6 Z9 6 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 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD MAR PY 2006 VL 236 IS 1 BP 29 EP 34 DI 10.1016/j.jms.2005.12.004 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 025HQ UT WOS:000236256500005 ER PT J AU Predoi-Cross, A Hambrook, K Brawley-Tremblay, S Bouanich, JP Devi, VM Smith, MAH AF Predoi-Cross, A Hambrook, K Brawley-Tremblay, S Bouanich, JP Devi, VM Smith, MAH TI Room-temperature broadening and pressure-shift coefficients in the nu(2) band of CH3D-O-2: Measurements and semi-classical calculations SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE monodeuterated methane; CH3D; O-2-broadening; Fourier transform infrared spectroscopy; spectral lineshape; semi-classical calculation ID DIODE-LASER MEASUREMENTS; NU(3) BAND; SHAPES; XE; CO AB We report measured Lorentz O-2-broadening and O-2-induced pressure-shift coefficients of CH3D in the nu(2) fundamental band. Using a multispectrum fitting technique we have analyzed 11 laboratory absorption spectra recorded at 0.011 cm(-1) resolution using the McMath-Pierce Fourier transform spectrometer, Kitt Peak, Arizona. Two absorption cells with path lengths of 10.2 and 25 cm were used to record the spectra. The total sample pressures ranged from 0.98 to 339.85 Torr with CH3D volume mixing ratios of 0.012 in oxygen. We report measurements for O-2 pressure-broadening coefficients of 320 nu(2) transitions with quantum numbers as high as J '' = 17 and K= 14, where K '' = K' = K (for a parallel band). The measured O-2-broadening coefficients range from 0.0153 to 0.0645 cm(-1) atm(-1) at 296 K. All the measured pressure-shifts are negative. The reported O-2-induced pressure-shift coefficients vary from about -0.0017 to -0.0068 cm(-1) atm(-1). We have examined the dependence of the measured broadening and shift parameters on the J '', and K quantum numbers and also developed empirical expressions to describe the broadening coefficients in terms of m (m = -J '', J '' and J '' + 1 in the P-Q-, (Q)Q-, and R-Q-branch, respectively) and K. On average, the empirical expressions reproduce the measured broadening coefficients to within 4.4%. The O-2-broadening and pressure shift coefficients were calculated on the basis of a semiclassical model of interacting linear molecules performed by considering in addition to the electrostatic contributions the atom-atom Lennard-Jones potential. The theoretical results of the broadening coefficients are generally larger than the experimental data. Using for the trajectory model an isotropic Lennard-Jones potential derived from molecular parameters instead of the spherical average of the atom-atom model, a better agreement is obtained with these data, especially for \m\ <= 12 values (11.3% for the first calculation and 8.1% for the second calculation). The O-2-pressure shifts whose vibrational contribution are either derived from parameters fitted in the (Q)Q-branch of self-induced shifts of CH3D or those obtained from pressure shifts induced by Xe in the nu(3) band of CH3D are in reasonable agreement with the scattered experimental data (17.0% for the first calculation and 18.7% for the second calculation). (C) 2005 Elsevier Inc. All rights reserved. C1 Univ Lethbridge, Dept Phys, Lethbridge, AB T1K 3M4, Canada. Univ Paris 11, CNRS, UPR3361, Photophys Mol Lab, F-91405 Orsay, France. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. NASA, Langley Res Ctr, Sci Directorate, Hampton, VA 23681 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 13 Z9 13 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 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD MAR PY 2006 VL 236 IS 1 BP 75 EP 90 DI 10.1016/j.jms.2005.12.012 PG 16 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 025HQ UT WOS:000236256500011 ER PT J AU Chen, P Pearson, JC Pickett, HM Matsuura, S Blake, GA AF Chen, P Pearson, JC Pickett, HM Matsuura, S Blake, GA TI Measurements of (NH3)-N-14 in the nu(2)=1 state by a solid-state, photomixing, THz spectrometer, and a simultaneous analysis of the microwave, terahertz, and infrared transitions between the ground and nu(2) inversion-rotation levels SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE NH3; ammonia; far-infrared; submillimeter; global fit; optical heterodyne; frequency; calibration; cavity; etalon; laser locking; metrology ID DIODE-LASER MEASUREMENTS; PYRAMIDAL XY3 MOLECULES; SUB-DOPPLER SPECTROSCOPY; POTENTIAL-ENERGY SURFACE; TEMPERATURE-GROWN GAAS; 2-PHOTON SPECTROSCOPY; STARK SPECTROSCOPY; NU-2 BAND; HETERODYNE MEASUREMENTS; LINE PARAMETERS AB In this paper, we report 30 THz measurements of ammonia in its excited, nu(2) = 1, inversion state. These measurements include transition frequencies and pressure shifts (where significant enough to be observed). Included in the data are two forbidden and three ro-inversion transitions, as well as 18 transitions never directly measured before. The measurements were made with an all-solid-state, diodelaser, difference-frequency spectrometer. Using an innovative laser-frequency locking scheme, this spectrometer provided accurately determined and continuously tuned THz-frequencies without requiring accurate knowledge of the absolute laser frequencies. The details of the spectrometer's frequency calibration is discussed. A global analysis of NH3 based on the available ground state, nu(2)=1 state, and nu(2)-band transitions was carried out, and the resulting set of recommended molecular effective-Hamiltonian parameters for ammonia is presented. In addition, calculated center frequencies and intensities for all possible transitions up to J = 20 between rotation, inversion, and vibration levels in the ground and nu(2)=1 states are included as supplementary material. (C) 2006 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Div Chem & Chem Engn, Pasadena, CA 91125 USA. Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. RP Chen, P (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-301,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM pin.chen@jpl.nasa.gov; john.c.pearson@jpl.nasa.gov; herbert.m.pickett@jpl.nasa.gov; matsuura@ir.isas.jaxa.jp; gab@gps.caltech.edu RI Chen, Pin/B-1112-2008; Matsuura, Shuji/B-5658-2016 OI Chen, Pin/0000-0003-1195-9666; Matsuura, Shuji/0000-0002-5698-9634 NR 89 TC 32 Z9 32 U1 1 U2 8 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 MAR PY 2006 VL 236 IS 1 BP 116 EP 126 DI 10.1016/j.jms.2006.01.002 PG 11 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 025HQ UT WOS:000236256500015 ER PT J AU Chupp, RE Hendricks, RC Lattime, SB Steinetz, BM AF Chupp, RE Hendricks, RC Lattime, SB Steinetz, BM TI Sealing in turbomachinery SO JOURNAL OF PROPULSION AND POWER LA English DT Review ID MECHANICAL FACE SEAL; TIP CLEARANCE; BRUSH SEAL; NUMERICAL-SIMULATION; TURBINE APPLICATIONS; PERFORMANCE; DESIGN; FLOWS; INSTABILITY; SYSTEMS AB Clearance control is of paramount importance to turbomachinery designers and is required to meet today's aggressive power output, efficiency, and operational life goals. Excessive clearances lead to losses in cycle efficiency, How instabilities, and hot gas ingestion into disk cavities. Insufficient clearances limit coolant flows and cause interface rubbing, overheating downstream components and damaging interfaces, thus limiting component life. Designers have put renewed attention on clearance control, as it is often the most cost-effective method to enhance system performance. Advanced concepts and proper material selection continue to play important roles in maintaining interface clearances to enable the system to meet design goals. This work presents an overview of turbomachinery seating to control clearances. Areas covered include characteristics of gas and steam turbine sealing applications and environments, benefits of sealing, types of standard static and dynamics seals, advanced seal designs, as well as life and limitations issues. C1 Gen Elect Global Res, Niskayuna, NY 12302 USA. NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. Timken Co, N Canton, OH 44720 USA. RP Chupp, RE (reprint author), Gen Elect Global Res, Niskayuna, NY 12302 USA. NR 188 TC 70 Z9 87 U1 4 U2 17 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 MAR-APR PY 2006 VL 22 IS 2 BP 313 EP 349 DI 10.2514/1.17778 PG 37 WC Engineering, Aerospace SC Engineering GA 022WO UT WOS:000236087000007 ER PT J AU Liew, KH Urip, E Yang, SL Mattingly, JD Mareo, CJ AF Liew, KH Urip, E Yang, SL Mattingly, JD Mareo, CJ TI Performance cycle analysis of turbofan engine with interstage turbine burner SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 40th Joint Propulsion Conference CY JUL 11-15, 2004 CL Ft Lauderdale, FL SP Amer Inst Aeronaut & Astronaut, ASME, SAE, ASEE ID INCREASES AB This paper presents the performance-cycle analysis of a dual-spool, separate-exhaust turbofan engine, with an interstage turbine burner (ITB) serving as a secondary combustor. The ITB, which is located at the transition duct between the high- and the low-pressure turbines.. is a relatively new concept for increasing specific thrust and lowering pollutant emissions in modern jet engine propulsion. A detailed performance analysis of this engine has been conducted for steady-state engine performance prediction. A code is written and is capable of predicting engine performances (i.e., thrust and thrust specific fuel consumption) at varying flight conditions and throttle settings. Two design-point engines were studied to reveal trends in performance at both full and partial throttle operations. A mission analysis is also presented to ensure the advantage of saving fuel by adding ITB. C1 Michigan Technol Univ, Houghton, MI 49931 USA. Mattingly Consulting, Bothell, WA 98011 USA. NASA, John H Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Liew, KH (reprint author), Michigan Technol Univ, Houghton, MI 49931 USA. NR 11 TC 4 Z9 6 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 MAR-APR PY 2006 VL 22 IS 2 BP 411 EP 416 DI 10.2514/1.13394 PG 6 WC Engineering, Aerospace SC Engineering GA 022WO UT WOS:000236087000014 ER PT J AU Sarkar, P Sarkar, S Ramesh, V Hayes, BE Thomas, RL Wilson, BL Kim, H Barnes, S Kulkarni, A Pellis, N Ramesh, GT AF Sarkar, P Sarkar, S Ramesh, V Hayes, BE Thomas, RL Wilson, BL Kim, H Barnes, S Kulkarni, A Pellis, N Ramesh, GT TI Proteomic analysis of mice hippocampus in simulated microgravity environment SO JOURNAL OF PROTEOME RESEARCH LA English DT Article DE microgravity; hippocampus; two-dimensional gel electrophoresis ID FACTOR-KAPPA-B; SPACE-FLIGHT; PARKINSONS-DISEASE; OXIDATIVE STRESS; ALPHA-SYNUCLEIN; PROTEIN; WEIGHTLESSNESS; NEURONS; SPACEFLIGHT; BRAIN AB Space travel induces many deleterious effects on the flight crew due to the '0' g environment. The brain experiences a tremendous fluid shift, which is responsible for many of the detrimental changes in physical behavior seen in astronauts. It therefore indicates that the brain may undergo major changes in its protein levels in a '0' g environment to counteract the stress. Analysis of these global changes in proteins may explain to better understand the functioning of brain in a '0' g condition. Toward such an effort, we have screened proteins in the hippocampus of mice kept in simulated microgravity environment for 7 days and have observed a few changes in major proteins as compared to control mice. Essentially, the results show a major loss of proteins in the hippocampus of mice subjected to simulated microgravity. These changes occur in structural proteins such as tubulin, coupled with the loss of proteins involved in metabolism. This preliminary investigation leads to an understanding of the alteration of proteins in the hippocampus in response to the microgravity environment. C1 Texas So Univ, Dept Biol, Mol Neurotoxicol Lab & Proteom Core, Houston, TX 77004 USA. Univ Texas, Dept Surg, Houston, TX 77030 USA. Univ Alabama, Dept Pharmacol & Toxicol, Birmingham, AL 35294 USA. NASA, JSC, Cellular Biotechnol Program, Houston, TX 77058 USA. RP Ramesh, GT (reprint author), Texas So Univ, Dept Biol, Mol Neurotoxicol Lab & Proteom Core, 3100 Cleburne St, Houston, TX 77004 USA. EM ramesh_gt@tsu.edu FU NCI NIH HHS [P30 CA013148, U54 CA100949, U54-CA100949, P30CA13148]; NCRR NIH HHS [G12 RR003045, G12 RR003045-180001, RR03045-18, S10 RR013795-01, S10 RR13795, S10 RR16949] NR 39 TC 24 Z9 30 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1535-3893 J9 J PROTEOME RES JI J. Proteome Res. PD MAR PY 2006 VL 5 IS 3 BP 548 EP 553 DI 10.1021/pr050274r PG 6 WC Biochemical Research Methods SC Biochemistry & Molecular Biology GA 020GP UT WOS:000235897000010 PM 16512669 ER PT J AU Uehara, S Nikjoo, H AF Uehara, S Nikjoo, H TI Monte Carlo simulation of water radiolysis for low-energy charged particles SO JOURNAL OF RADIATION RESEARCH LA English DT Article ID TRACK STRUCTURE CODES; LIQUID WATER; CROSS-SECTIONS; HYDRATED ELECTRON; AQUEOUS-SOLUTIONS; PULSE-RADIOLYSIS; OH RADICALS; SUBEXCITATION ELECTRONS; QUANTITATIVE-ANALYSIS; INELASTIC-SCATTERING AB The paper describes the development of chemical modules simulating the prechemical and chemical stages of charged particle tracks in pure liquid water. These calculations are based on our physical track structure codes for electrons and ions (KURBUC, LEPHIST and LEAHIST) which provide the initial spatial distribution of H2O+, H2O* and subexcitation electrons at similar to 10(-15) s. We considered 11 species and 26 chemical reactions. A step-by-step Monte Carlo approach was adopted for the chemical stage between 10(-12) s and 10(-6) s. The chemistry codes enabled to simulate the non-homogeneous chemistry that pertains to electron, proton and alpha-particle tracks of various linear energy transfers (LET). Time-dependent yields of chemical species produced by electrons and ions of different energies were calculated. The calculated primary yields (G values at 10(-6) s) of 2.80 for OH and 2.59 for e(aq)(-) for 1 MeV electrons are in good agreement with the published values. The calculated G values at 10-6 s for a wide range LETS from of 0.2 to 235 keV mu m(-1) were obtained. The calculations show the LET dependence for OH and H2O2. The electron penetration ranges were calculated in order to discuss the role of low energy electrons. C1 Kyushu Univ, Sch Hlth Sci, Fukuoka 8128582, Japan. NASA, Johnson Space Ctr, Ctr Adv Space Studies, USRA, Houston, TX 77058 USA. RP Uehara, S (reprint author), Kyushu Univ, Sch Hlth Sci, Maidashi 3-1-1, Fukuoka 8128582, Japan. EM shuzohsg@mbox.nc.kyushu-u.ac.jp NR 63 TC 34 Z9 35 U1 0 U2 10 PU JAPAN RADIATION RESEARCH SOC PI CHIBA PA C/O NAT INST RADIOLOGICAL SCI 9-1 ANAGAWA-4-CHOME INAGE-KU, CHIBA, 263, JAPAN SN 0449-3060 J9 J RADIAT RES JI J. Radiat. Res. PD MAR PY 2006 VL 47 IS 1 BP 69 EP 81 DI 10.1269/jrr.47.69 PG 13 WC Biology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Radiology, Nuclear Medicine & Medical Imaging GA 040SD UT WOS:000237399800008 PM 16571920 ER PT J AU Wilkinson, MJ Marshall, LG Lundberg, JG AF Wilkinson, MJ Marshall, LG Lundberg, JG TI River behavior on megafans and potential influences on diversification and distribution of aquatic organisms SO JOURNAL OF SOUTH AMERICAN EARTH SCIENCES LA English DT Article DE abiotic control; aquatic organisms; distribution; diversity; Megafan; river behavior ID STICKLEBACK GASTEROSTEUS-ACULEATUS; FLUVIAL MEGAFANS; SOUTH-AMERICA; OKAVANGO FAN; SYSTEMS; BASIN; SPECIATION; AVULSION; FISHES; LAKES AB Megafans are partial cones of river sediment usually laid down by a single switching river, characterized by areas on the order of 10(3)-10(5) km(2), smooth plains, and slopes of < 1 degrees. Astronaut handheld imagery acquired since the early 1980s has permitted the first global geomorphic survey of megafans. Using examples mainly from South America, and based on stream behaviors common in megafans, seven models that appear to have implications for the distribution and diversification of aquatic organisms are presented. River behaviors that appear significant for the fragmentation and age of aquatic habitats on megafans include river switching (models 1.1-1.4) and the disconnection of the megafan river from the main river of the basin (models 2-4). Each model has a habitat fragmentation and a habitat combining mode. In their vicariant mode, models 1.1 and 1.2 involve longer periods of time. Models 1.3 and 1.4 involve the relatively instantaneous merging of aquatic populations from neighboring megafan rivers or neighboring major basins. Models 2-4 involve longer-term dynamics with the potential for speciation. We identify the following levels of diversity related to scales of stream operation: intrafan diversity, or local populations and among local populations; interfan diversity, or among local populations and species; and interbasin diversity, or species and biotas. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Image Sci & Anal Lab, Jacobs Sverdrup ESCG, Houston, TX 77258 USA. Mesa SW Museum, Dept Palaeontol, Mesa, AZ 85201 USA. Acad Nat Sci Philadelphia, Dept Ichthyol, Philadelphia, PA 19103 USA. RP Wilkinson, MJ (reprint author), NASA, Lyndon B Johnson Space Ctr, Image Sci & Anal Lab, Jacobs Sverdrup ESCG, POB 58447,Code JE36-1, Houston, TX 77258 USA. EM jwilkin1@ems.jsc.nasa.gov NR 75 TC 33 Z9 34 U1 4 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0895-9811 J9 J S AM EARTH SCI JI J. South Am. Earth Sci. PD MAR PY 2006 VL 21 IS 1-2 SI SI BP 151 EP 172 DI 10.1016/j.jsarnes.2005.08.002 PG 22 WC Geosciences, Multidisciplinary SC Geology GA 060DG UT WOS:000238781800012 ER PT J AU Lockwood, MK Powell, RW Sutton, K Prabhu, RK Graves, CA Epp, CD Carman, GL AF Lockwood, MK Powell, RW Sutton, K Prabhu, RK Graves, CA Epp, CD Carman, GL TI Entry configurations and performance comparisons for the Mars Smart Lander SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB The Mars Smart Lander (MSL, renamed and redefined as the Mars Science Laboratory) will provide scientists with access to previously unachievable landing sites by providing precision landing to less than 10 km of a target landing site with landing altitude capability to 2.5 km above the Mars Orbiter Laser Altimeter geoid. Precision landing is achieved by using the aerodynamic forces on the entry body to aeromaneuver through the Martian atmosphere during the entry phase of flight. The entry body is designed to provide aerodynamic lift. The direction of the aerodynamic lift vector, defined by the vehicle bank angle, is commanded by the onboard entry guidance, to converge downrange and crossrange errors by parachute deploy, while meeting the parachute deploy constraints. Several approaches and entry body configurations for providing aerodynamic lift can be considered, including axisymmetric capsule configurations with offset c.g.s using ballast or packaging, aerodynamically shaped capsule-type configurations, and alternate configurations such as mid-lift-to-drag-ratio vehicles. The design considerations, entry configurations, and entry performance of the Mars Smart Lander are described. C1 NASA, Langley Res Ctr, Explorat Syst Engn Branch, Hampton, VA 23681 USA. Natl Inst Aerosp, Hampton, VA 23666 USA. Lockheed Martin Engn & Sci Co, Lockheed Martin Space Operat, Langley Program Off, Hampton, VA 23681 USA. NASA, Lyndon B Johnson Space Ctr, Explorat Syst Engn Div, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Flight Design & Dynam Div, Houston, TX 77058 USA. RP Lockwood, MK (reprint author), NASA, Langley Res Ctr, Explorat Syst Engn Branch, Mail Stop 489, Hampton, VA 23681 USA. NR 15 TC 15 Z9 15 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 MAR-APR PY 2006 VL 43 IS 2 BP 258 EP 269 PG 12 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100002 ER PT J AU Horvath, TJ O'Connell, TF Cheatwood, FM Prabhu, RK Alter, SJ AF Horvath, TJ O'Connell, TF Cheatwood, FM Prabhu, RK Alter, SJ TI Experimental hypersonic aerodynamic characteristics of Mars Surveyor 2001 Precision Lander with flap SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID ENTRY AB Aerodynamic wind-tunnel screening tests were conducted on a 0.029-scale model of a proposed Mars Surveyor 2001 Precision Lander (70-deg half-angle spherically blunted cone with a conical afterbody). The primary experimental objective was to determine the effectiveness of a single flap to trim the vehicle at incidence during a lifting hypersonic planetary entry. The laminar force and moment data, presented in the form of coefficients, and shock patterns from schlieren photography were obtained in the facilities of the NASA Langley Aerothermodynamic Laboratory for postnormal shock Reynolds numbers (based on forebody diameter) ranging from 2.637 x 10(3) to 92.35 x 10(3), angles of attack ranging from 0 up to 23 deg at 0- and 2-deg sideslip, and normal-shock density ratios of 5 and 12. Based upon the proposed entry trajectory of the 2001 Lander, tests in the heavy gas CF4 simulate a Mach number of approximately 12 based upon a normal shock density ratio of 12 in flight at Mars. The results from this experimental study suggest that when the traditional means of providing aerodynamic trim for this class of planetary entry vehicle are not possible (e.g., offset e.g.), a single flap can provide similar aerodynamic performance. An assessment of blunt-body aerodynamic effects attributed to a real gas was obtained by synergistic testing in Mach 6 ideal air at a comparable Reynolds number. From an aerodynamic perspective, an appropriately sized flap was found to provide sufficient trim capability at the desired lift-to-drag ratio for precision landing. Inviscid hypersonic flow computations using an unstructured grid were made to provide an assessment of the viability of a flap to provide aerodynamic trim to the Lander. Subsequent Navier-Stokes computational predictions were found to be in very good agreement with experimental measurement. C1 NASA, Langley Res Ctr, Space Access & Explorat Program Off, Hampton, VA 23681 USA. Lockheed Martin Engn & Sci Co, Houston, TX USA. RP Horvath, TJ (reprint author), NASA, Langley Res Ctr, Space Access & Explorat Program Off, Hampton, VA 23681 USA. NR 28 TC 2 Z9 3 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 MAR-APR PY 2006 VL 43 IS 2 BP 270 EP 281 DI 10.2514/1.19651 PG 12 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100003 ER PT J AU Murphy, KJ Horvath, TJ Erickson, GE Green, JM AF Murphy, KJ Horvath, TJ Erickson, GE Green, JM TI Supersonic aerodynamic characteristics of proposed Mars '07 Smart Lander configurations SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Supersonic aerodynamic data were obtained for proposed Mars '07 Smart Lander configurations in NASA Langley Research Center's Unitary Plan Wind Tunnel. The primary objective of this test program was to assess the supersonic aerodynamic characteristics of the baseline Smart Lander configuration with and without fixed shelf/tab control surfaces. Data were obtained over a Mach-number range of 2.3-4.5, at a freestream Reynolds number of 1 X 10(6) based on body diameter. All configurations were run at angles of attack from -5 to 20 deg and angles of sideslip of -5 to 5 deg. These results were complemented with computational fluid dynamic predictions to enhance the understanding of experimentally observed aerodynamic trends. Inviscid and viscous full model computational solutions compared well with experimental results for the baseline and three shelf/tab configurations. Over the range tested, Mach-number effects were shown to be small on vehicle aerodynamic characteristics. Based on the results from, three different shelf/tab configurations, a fixed-control surface appears to be a feasible concept for meeting aerodynamic performance metrics necessary to satisfy mission requirements. C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Res Facil Branch, Hampton, VA 23681 USA. Mississippi State Univ, Mississippi State, MS 39762 USA. RP Murphy, KJ (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 10 TC 3 Z9 3 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 MAR-APR PY 2006 VL 43 IS 2 BP 282 EP 292 DI 10.2514/1.19663 PG 11 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100004 ER PT J AU Brown, J Yates, L Bogdanoff, D Chapman, G Loomis, M Tam, T AF Brown, J Yates, L Bogdanoff, D Chapman, G Loomis, M Tam, T TI Free-flight testing in support of the Mars Science Laboratory aerodynamics database SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB An extensive ballistic range test program to study the aerodynamic characteristics of two possible configurations for the Mars Science Laboratory entry vehicle is presented. Testing focused primarily on static and dynamic aerodynamic coefficients, in the pitch plane, for a tabbed geometry flying supersonically in carbon dioxide. Limited data were also obtained for tabbed models in air and for axisymmetric models, similar to the Viking/Pathfinder forebody shaped at supersonic and hypersonic Mach numbers in CO2. Innovations in testing and data-reduction procedures that enhanced experimental capabilities and reduced data uncertainties are described. In CO2, the tabbed configuration was dynamically stable, in pitch, for all trim angles and Mach numbers tested. Preliminary data showed the same vehicle to be unstable in air, suggesting the possibility of a significant gas-composition effect on pitch damping. In general, the experimental data agreed well with pretest computations. C1 Eloret Corp, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Reacting Flow Environm Branch, Moffett Field, CA 94035 USA. Aerosp Comp Inc, Mountain View, CA 94305 USA. NASA, Ames Res Ctr, Reacting Flow Environm Branch, Moffett Field, CA 94035 USA. RP Brown, J (reprint author), Eloret Corp, Moffett Field, CA 94035 USA. NR 13 TC 2 Z9 2 U1 1 U2 3 PU AMER INST AERONAUTICS ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 EI 1533-6794 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2006 VL 43 IS 2 BP 293 EP 302 DI 10.2514/1.19221 PG 10 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100005 ER PT J AU Bobskill, GJ Parikh, PC Prabhu, RK Tyler, ED AF Bobskill, GJ Parikh, PC Prabhu, RK Tyler, ED TI Aerodynamic database development for Mars Smart Lander vehicle configurations SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB An aerodynamic database has been generated for the Mars Smart Lander shelf-all configuration. Beginning with all effort to validate the computational tools against sets of experimental data, the static aerodynamic database was constructed by correcting experimental data to Mars atmospheric flight conditions at supersonic speeds, in addition to performing discrete hypersonic analyses in the continuum and noncontinuum atmospheric regimes. Three different computational fluid dynamics codes, two based on unstructured grid technology and one an established and validated structured grid-based code, were used. As part of this database development, the results for the Mars continuum atmosphere were validated with experimental data and comparisons made where applicable. The validation with the Unitary experimental data, the use of intermediate check analyses, and the validation with the Mach 6 CF4 experimental data provided a higher confidence in the ability of the computational analyses to provide accurate aerodynamic data for the determination of static trim characteristics for longitudinal stability within the continuum and noncontinuum atmospheric regimes. The analyses of the noncontinuum regime showed the existence of multiple trim angles of attack that can be unstable or stable trial points. These trends assisted in the development of all entry controller for a nominal trajectory. C1 NASA, Langley Res Ctr, Verhicle Anal Branch, Syst Anal & Concepts Directorate, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Configurat Aerodynam Branch, Res & Technol Directorate, Hampton, VA 23681 USA. Lockheed Marting Engn & Sci Co, Hampton, VA 23681 USA. Swales Aerosp, Hampton, VA 23681 USA. RP Bobskill, GJ (reprint author), NASA, Langley Res Ctr, Verhicle Anal Branch, Syst Anal & Concepts Directorate, Hampton, VA 23681 USA. NR 22 TC 4 Z9 4 U1 1 U2 3 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 MAR-APR PY 2006 VL 43 IS 2 BP 303 EP 310 DI 10.2514/1.19223 PG 8 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100006 ER PT J AU Striepe, SA Way, DW Dwyer, AM Balaraim, J AF Striepe, SA Way, DW Dwyer, AM Balaraim, J TI Mars Science Laboratory simulations for entry, descent, and landing SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID REFERENCE-ATMOSPHERIC-MODEL; DISPERSION ANALYSIS; SMART-LANDER; AERODYNAMIC DATABASE; CONFIGURATIONS; DESIGN; GRAM AB Two primary simulations have been developed and are being updated for the Mars Science Laboratory entry, descent, and landing. The high-fidelity engineering end-to-end entry, descent, and landing simulation is based on NASA Langley Research Center's Program to Optimize Simulated Trajectories II and the end-to-end real-time, hardwaee-in-the-loop simulation test bed, which is based on NASA Jet Propulsion Laboratory's Dynamics Simulator for Entry, Descent, and Surface landing. The status of these Mars Science Laboratory entry, descent, and landing end-to-end simulations at this time is presented. Various models, capabilities, as well as validation and verification for these simulations, are discussed. C1 NASA, Langley Res Ctr, Explorat Syst Engn Branch, SED, Hampton, VA 23681 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Striepe, SA (reprint author), NASA, Langley Res Ctr, Explorat Syst Engn Branch, SED, Hampton, VA 23681 USA. NR 52 TC 33 Z9 37 U1 0 U2 4 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 MAR-APR PY 2006 VL 43 IS 2 BP 311 EP 323 DI 10.2514/1.19649 PG 13 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100007 ER PT J AU Calhoun, PC Queen, EA AF Calhoun, PC Queen, EA TI Entry vehicle control system design for the Mars Science Laboratory SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB The NASA Langley Research Center, in cooperation with the Jet Propulasion Laboratorty, participated in a preliminary design study of the entry, descent, and landing phase for the Mars Science Laboratory Project. This project uses advances in guidance, navigation, and control technology to significantly improve Mars surface targeting capability. A candidate entry controller based on the reaction control system controller for the Apollo command module digital autopilot is proposed for use in the entry attitude control. Modifications to the phase plane controller provide good bank-angle response, reduce jet-firing chattering for hogh-frequency updates, and allow for the option of aerodynamic angle feedback for the Martian entry probe application. The controller performance is demonstrated in a six-degrees-of-freedom simulation with representative aerodynamics. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Calhoun, PC (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 11 TC 11 Z9 16 U1 1 U2 9 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 MAR-APR PY 2006 VL 43 IS 2 BP 324 EP 329 DI 10.2514/1.19650 PG 6 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100008 ER PT J AU Edquist, KT Liechty, DS Hollis, BR Alter, SJ Loomis, MP AF Edquist, KT Liechty, DS Hollis, BR Alter, SJ Loomis, MP TI Aeroheating environments for a Mars Smart Lander SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Computational predictions of the Mars Smart Lander forebody aeroheating environments are given for a direct entry trajectory. The solutions were obtained using an eight-species gas in thermal and chemical nonequilibrium with a radiative-equilibrium wall-temperature boundary condition. Select wind-tunnel data are presented from tests at NASA Langley Research Center. Turbulence effects are included to account for both smooth body transition and turbulence caused by heat-shield penetrations. Natural transition is based on a momentum-thickness Reynolds number value of 200. The effects of heat-shield penetrations on turbulence are estimated from wind-tunnel tests of various cavity sizes and locations. Both natural transition and heat-shield penetrations are predicted to cause turbulence before the nominal trajectory peak heating time. Laminar and turbulent computational predictions along the trajectory are used to estimate heat rates and loads. The predicted peak turbulent heat rate of 63 W/cm(2) on the heat-shield leeward flank is 70% higher than the laminar peak. The maximum integrated heat load for a fully turbulent heat pulse is 38% higher than the maximum laminar load. The predicted heating environments, including uncertainty factors, will be used to design a thermal protection system. C1 NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NASA, Ames Res Ctr, Nanotechnol Branch, Moffett Field, CA 94035 USA. RP Edquist, KT (reprint author), NASA, Langley Res Ctr, Vehicle Anal Branch, MS 365, Hampton, VA 23681 USA. NR 33 TC 11 Z9 11 U1 0 U2 2 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 MAR-APR PY 2006 VL 43 IS 2 BP 330 EP 339 DI 10.2514/1.19431 PG 10 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100009 ER PT J AU Liechty, DS Hollis, BR Edquist, KT AF Liechty, DS Hollis, BR Edquist, KT TI Mars Science Laboratory experimental aerothermodynamics with effects of cavities and control surfaces SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID SCHEMES AB Preliminary designs of the Mars Science Laboratory required it to be attached through its aeroshell to the main spacecraft bus, thereby producing cavities in the heat shield. Several configurations were considered experimentally for the Mars Science Laboratory, which have a Viking aeroshell heritage and provide the lift to drag required for precision landing. To study the effects of the cavities and control surfaces on the heating levels experienced by the heat shield, an experimental aeroheating investigation was performed at the NASA Langley Research Center in the 20-Inch Mach 6 Air Tunnel. Three configurations were studied experimentally. The first configuration was the baseline without any control surface. The last two include a blended tab control surface and a blended shelf control surface. The effects of Reynolds number, angle of attack, and cavity size and location on aeroheating levels and distributions were determined for each configuration and are presented. To aid the interpretation of the effects of the cavities, laminar, thin-layer Navier-Stokes flowfield solutions were performed for the baseline configuration and were then postprocessed to calculate relevant boundary-layer properties. It was found that the effect of the cavities varied with angle of attack, freestream Reynolds number, and cavity size and location. The presence of a cavity raised local heating rates by as much as 250% and the downstream heating rates by as much as 325% as a result of boundary-layer transition. Forebody cavities had no effect on afterbody heating, and the presence of control surfaces decreased leeward afterbody heating slightly. C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. RP Liechty, DS (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 19 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 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAR-APR PY 2006 VL 43 IS 2 BP 340 EP 353 DI 10.2514/1.19671 PG 14 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100010 ER PT J AU Hollis, BR Liechty, DS AF Hollis, BR Liechty, DS TI Transition due to heat-shield cavities on a Mars entry vehicle SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID SCHEMES AB The influence of heat-shield cavities on the forebody of the proposed Mars Science Laboratory entry vehicle has been investigated experimentally and computationally. Wind-tunnel tests were conducted on the 70-deg sphere-cone forebody of the vehicle with various cavity sizes and locations to assess their effects on convective heating and boundary-layer transition. The heat-transfer coefficients and transition locations were measured using global phos-phor thermography. Laminar and turbulent Navier-Stokes computations were performed to compare with the experimental aeroheating data and to determine boundary-layer parameters for use in correlation of the experimental transition data. Comparisons of laminar heating data and computations were found to agree to within the experimental uncertainty, but turbulent computations underpredicted measured heating levels by up to 20%, possibly because the cavities were not included in the simple computational geometry employed. The cavity transition data were analyzed to determine a correlation for transition to turbulence at a cavity in terms of cavity geometric parameters and computed boundary-layer conditions. This correlation was used to show that the vehicle could experience early onset of turbulent How in flight as a result of the presence of cavities. C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. RP Hollis, BR (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 27 TC 11 Z9 13 U1 0 U2 2 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 MAR-APR PY 2006 VL 43 IS 2 BP 354 EP 366 DI 10.2514/1.19669 PG 13 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100011 ER PT J AU Laub, B White, S AF Laub, B White, S TI Arcjet screening of candidate ablative thermal protection materials for Mars Science Laboratory SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Arc plasma tests of a range of ablative materials considered candidates for the thermal protection system for the Mars Science Laboratory are described. The objective of these tests was to identify ablative thermal protection materials that offer weight, performance, cost, or other advantages relative to SLA-561V Several low-density silicones with a mixture of low-density fillers and polymer-impregnated ceramics were tested in the Ames Interaction Heating Facility at conditions representative of nominal stagnation point and worst-case conical heating on the Mars Smart Lander forebody. A wide variety of low-density ablatives and impregnated flexible materials were tested in the Ames Panel Test Facility at nominal and worst-case heating for the Mars Smart Lander backshell. The results of these tests have identified several attractive materials worthy of further investigation. C1 NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Moffett Field, CA 94035 USA. RP Laub, B (reprint author), NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, MS 234-1, Moffett Field, CA 94035 USA. NR 9 TC 1 Z9 1 U1 1 U2 6 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 MAR-APR PY 2006 VL 43 IS 2 BP 367 EP 373 DI 10.2514/1.19218 PG 7 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100012 ER PT J AU Queen, EM Raiszadeh, B AF Queen, EM Raiszadeh, B TI Mars Science Laboratory parachute simulation model SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A multibody. flight simulation for the Mars Science Laboratory that includes six-degree-of-freedom rigid-body models for both the supersonically deployed and subsonically deployed parachutes has been developed. This provides a complete end-to-end simulation of the entire entry, descent, and landing sequence. The simulation provides attitude history predictions of all bodies throughout the flight as well as loads on each of the connecting lines. Other issues such as recontact with jettisoned elements (heat shield, backshell, parachute mortar covers, etc.), design of parachute and attachment points, and desirable line properties can also be addressed readily using this simulation. Time histories of the parachute line loads and the parachute and lander aerodynamic angles are presented. The simulation shows that the backshell does not recontact the lander after separation. C1 NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. RP Queen, EM (reprint author), NASA, Langley Res Ctr, Vehicle Anal Branch, Hampton, VA 23681 USA. NR 8 TC 1 Z9 2 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 MAR-APR PY 2006 VL 43 IS 2 BP 374 EP 377 DI 10.2514/1.19668 PG 4 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100013 ER PT J AU Wong, EC Singh, G Masciarelli, JP AF Wong, EC Singh, G Masciarelli, JP TI Guidance and control design for hazard avoidance and safe landing on Mars SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB To ensure successful future Mars landing missions, the lander must be capable of detecting hazards in the nominal landing zone and maneuvering to a new and safe site. Trajectory guidance and attitude commanding are formulated for the terminal descent phase when the lander is off the parachute. The autonomous six-degree-of-freedom controls are accomplished using engines and thrusters and guided by onboard hazard-avoidance sensors. The algorithms determine the available landing zone, survey them for hazards, select the best or alternate landing site based on state estimates and available propellant, and then maneuver the lander to land safely at the selected site. Computer simulations have demonstrated the satisfactory performance of the algorithms for safe landing on Mars with assumed atmospheric environments. C1 CALTECH, Jet Prop Lab, Auton & Control Sect, Pasadena, CA 91101 USA. NASA, Lyndon B Johnson Space Ctr, Aerosci & Flight Mech Div, Houston, TX 77058 USA. RP Wong, EC (reprint author), CALTECH, Jet Prop Lab, Auton & Control Sect, Pasadena, CA 91101 USA. NR 5 TC 14 Z9 19 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 MAR-APR PY 2006 VL 43 IS 2 BP 378 EP 384 DI 10.2514/1.19220 PG 7 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100014 ER PT J AU Dever, JA Banks, BA Yan, L AF Dever, JA Banks, BA Yan, L TI Effects of vacuum ultraviolet radiation on DC93-500 silicone 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 Vacuum ultraviolet radiation is among the space environment elements that can be hazardous to DC93-500 silicone film, which has been proposed for use on spacecraft exterior surfaces. Investigations have been conducted to examine vacuum ultraviolet effects on DC93-500 film. Laboratory exposure tests were used to determine the effectiveness of various wavelength ranges in causing optical and mechanical degradation and to determine intensity-dependence of optical and mechanical properties degradation. Results indicated that wavelengths between 185 and 200 nm were significantly more effective in causing degradation than wavelengths between 140 and 185 run. These findings were consistent with results of vacuum ultraviolet ellipsometric optical measurements, which provided data on depth of penetration in DC93-500 as a function of wavelength. Wavelengths between 185 and 200 nm penetrate to depths between 1 and 3 mu m in DC93-500, depths where bulk degradation is likely, whereas the penetration of shorter wavelengths is much more shallow and more likely to result in only surface degradation. Results of exposures of DC93-500 film samples to vacuum ultraviolet radiation of intensities between 1.5 and 5.5 times the sun's intensity indicated no intensity-dependence of optical and mechanical property degradation. C1 NASA, John H Glenn Res Ctr Lewis Field, Electrophys Branch, Cleveland, OH 44135 USA. Univ Nebraska, Dept Elect Engn, Lincoln, NE 68588 USA. RP Dever, JA (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Electrophys Branch, MS 309-2,21000 Brookpk Rd, Cleveland, OH 44135 USA. NR 12 TC 12 Z9 12 U1 0 U2 6 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 MAR-APR PY 2006 VL 43 IS 2 BP 386 EP 392 DI 10.2514/1.15226 PG 7 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100016 ER PT J AU Dworak, DR Banks, BA Karniotis, CA Soucek, MD AF Dworak, DR Banks, BA Karniotis, CA Soucek, MD TI Evaluation of protective silicone/siloxane coatings in simulated low-earth-orbit environment 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 ATOMIC OXYGEN; CERAMER COATINGS; POLYIMIDES; POLYURETHANE; DEGRADATION; RADIATION AB A protective silicone/siloxane hybrid coating was prepared using a polysiloxane binder and nanophase silicon-oxo clusters. Siloxane clusters were formed in situ from sol-gel precursors during the UV-curing process. which is accomplished through a cationic curing mechanism at ambient temperatures. The binder of the coating was a methyl-substituted silicone oligomer, and the siloxane/silicon-oxo phase was prepared from tetraethoxysilane (TEOS). Alkoxy silane groups were also grafted onto the silicone oligomer to couple with a chain, to couple with the silicon-oxo clusters. Scanning electron and atomic force microscopy, x-ray photoelectron spectroscopy, and UV absorbance/transmittance studies were used to observe the silicone/siloxane hybrids performance in low-Earth-orbit simulators. The results show that a protective oxide layer was formed, and at moderate fluence levels (2.22 X 10(21) atoms/cm(2)) the silicone/siloxane hybrid coating did not exhibit microcracking and had appreciable specular transmittance. C1 Univ Akron, Dept Polymer Engn, Polymer Engn Acad Ctr, Akron, OH 44325 USA. NASA, John H Glenn Res Ctr, Electrophys Branch, Cleveland, OH 44135 USA. QSS Grp Inc, Cleveland, OH 44135 USA. RP Dworak, DR (reprint author), Univ Akron, Dept Polymer Engn, Polymer Engn Acad Ctr, 250 S Forge St, Akron, OH 44325 USA. EM msoucek@uakron.edu NR 34 TC 13 Z9 15 U1 1 U2 8 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 MAR-APR PY 2006 VL 43 IS 2 BP 393 EP 401 DI 10.2514/1.15787 PG 9 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100017 ER PT J AU de Groh, KK Banks, BA Ma, D AF de Groh, KK Banks, BA Ma, D TI Ground-to-space effective atomic oxygen fluence correlation for DC 93-500 silicone 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 The objective of this research was to calibrate the ground-to-space effective atomic oxygen fluence for DC 93-500 silicone in a thermal energy electron cyclotron resonance (ECR) oxygen plasma facility. A technique has been developed at NASA Glenn Research Center to determine the equivalent amount of atomic oxygen exposure in an ECR ground-test facility to produce the same degree of atomic oxygen damage as in space. The approach used was to compare changes in the surface hardness of ground test (ECR)-exposed DC 93-500 silicone with DC 93-500 exposed to low Earth orbit (LEO) atomic oxygen as part of a shuttle flight experiment. The ground-to-space effective atomic oxygen fluence correlation was determined based on the fluence in the ECR source that produced the same hardness for the fluence in space. A nanomechanical measurement system operated in conjunction with an atomic force microscope (AFM) was used to determine the surface hardness of the silicones. Hardness vs contact depth measurements were obtained for five ECR-exposed DC 93-500 samples (ECR exposed for 18 to 40 h, corresponding to Kapton effective fluences of 4.2 x 10(20) to 9.4 x 10(20) atoms/cm(2), respectively) and for space-exposed DC 93-500 from the Evaluation of Oxygen Interactions with Materials III (EOIM IR) shuttle flight experiment, exposed to LEO atomic oxygen (2.3 X 10(20) atoms/cm(2)). Pristine controls for the ECR tests and for the EOIM III flight sample were also evaluated. A ground-to-space correlation value was determined based on correlation values for four contact depths (150, 200, 250, and 300 nm), which represent the near-surface depth data. The results indicate that the Kapton effective atomic oxygen fluence in the ECR facility needs to be 2.64 times higher than in LEO to replicate equivalent exposure damage in the ground test silicone as occurred in the space exposed silicone. C1 NASA, John H Glenn Res Ctr, Electrophys Branch, Cleveland, OH 44233 USA. Lockheed Martin Space Syst, Sunnyvale, CA 94089 USA. RP de Groh, KK (reprint author), NASA, John H Glenn Res Ctr, Electrophys Branch, Lewis Field,M S 309-2,21000 Brookpk Rd, Cleveland, OH 44233 USA. NR 7 TC 2 Z9 2 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 MAR-APR PY 2006 VL 43 IS 2 BP 414 EP 420 DI 10.2514/1.14990 PG 7 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100020 ER PT J AU Kleiman, JI Gudimenko, Y Ng, R Iskanderova, ZA Grigorevski, A Kiseleva, L Edwards, D Finckenor, A AF Kleiman, JI Gudimenko, Y Ng, R Iskanderova, ZA Grigorevski, A Kiseleva, L Edwards, D Finckenor, A TI Surface modification of conductive and nonconductive paints for space durability enhancement 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 LOW-EARTH-ORBIT; ATOMIC OXYGEN; POLYMERS; EROSION AB A program was initiated to further improve the space durability of nonconductive polymer-based paints and of conductive thermal control paints presently tinder development. The results of surface modification of both types of paints, including the ground-based testing and performance evaluation, are presented. Functional properties and performance characteristics, such as thermal optical properties and surface resistivity characteristics of pristine and treated materials, were verified. Tests results revealed that the successfully treated materials did not exhibit any mass loss or surface morphology change, thus, indicating good protection front the severe oxidative environment. It was demonstrated that the developed surface modification treatment can be applied successfully to charge dissipative paints. C1 Integr Testing Lab Inc, Space Mat Div, Markham, ON L3R 2R7, Canada. Publ Joint Stock Co Composite, Space Mat Testing, Korolev 141070, Moscow region, Russia. Publ Joint Stock Co Composite, Space Mat Dept, Korolev 141070, Moscow region, Russia. NASA, George C Marshall Space Flight Ctr, Environm Effects Grp, Huntsville, AL 35812 USA. RP Kleiman, JI (reprint author), Integr Testing Lab Inc, Space Mat Div, 80 Esna Pk Dr,Units 7-9, Markham, ON L3R 2R7, Canada. EM jkleiman@itlinc.com; kompozit.mat@g23.relcom.ru; kompozi.mat@g23.relcom.ru; david.edwards@nasa.gov; miria.finckenor@nasa.gov NR 25 TC 4 Z9 4 U1 0 U2 3 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 MAR-APR PY 2006 VL 43 IS 2 BP 443 EP 450 DI 10.2514/1.6703 PG 8 WC Engineering, Aerospace SC Engineering GA 037AM UT WOS:000237119100026 ER PT J AU Lane, JE Youngquist, RC Haskell, WD Cox, RB AF Lane, JE Youngquist, RC Haskell, WD Cox, RB TI A hail size distribution impact transducer SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB An active impact transducer has been designed and tested for the purpose of monitoring hail fall in the vicinity of the Space Shuttle launch pads. An important outcome of this design is the opportunity to utilize frequency analysis to discriminate between the audio signal generated from raindrop impacts and that of hailstone impacts. The sound of hail impacting a metal plate is subtly but distinctly different from the sound of rain impacts. This useful characteristic permits application of signal processing algorithms that are inherently more robust than techniques relying on amplitude processing alone in the implementation of a hail disdrometer. (c) 2006 Acoustical Society of America C1 ASRC Aerosp Corp, Kennedy Space Ctr, FL 32815 USA. NASA, Kennedy Space Ctr, FL 32899 USA. RP Lane, JE (reprint author), ASRC Aerosp Corp, POB 21087, Kennedy Space Ctr, FL 32815 USA. EM John.Lane-1@ksc.nasa.gov; Robert.C.Youngquist@nasa.gov; William.Haskell-1@nasa.gov; Robert.Cox-1@ksc.nasa.gov NR 13 TC 0 Z9 0 U1 1 U2 3 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAR PY 2006 VL 119 IS 3 BP EL47 EP EL53 DI 10.1121/1.2166947 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 023VU UT WOS:000236155100059 ER PT J AU Reidmiller, DR Hobbs, PV Kahn, R AF Reidmiller, DR Hobbs, PV Kahn, R TI Aerosol optical properties and particle size distributions on the east coast of the united states derived from airborne in situ and remote sensing measurements SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID MID-ATLANTIC COAST; CHEMICAL APPORTIONMENT; CLAMS EXPERIMENT; DEPTH; OCEAN; SENSITIVITY; RETRIEVAL; TARFOX; NEPHELOMETER; CALIBRATION AB Airborne in situ measurements of vertical profiles and horizontal transects of aerosol optical and physical properties, obtained during the Chesapeake Lighthouse and Aircraft Measurements for Satellites (CLAMS) field campaign off the East Coast of the United States during the summer of 2001, are presented. Most of the measurements were obtained in relatively clean air dominated by airflows that had passed over Canada and the northern Atlantic Ocean. Results from the 17 July and 2 August 2001 flights are presented; on these days, the aerosol loading was relatively high. In the lower troposphere, omega(0) values at a wavelength of 550 nm were consistently above 0.93 throughout the field experiment, indicating the dominance of weakly absorbing aerosol. Particle number size distributions are presented and discussed for transects at altitudes similar to 0.05-3.5 km above mean sea level. Particles with diameters (D-p) < 0.1 mu m made up the majority of the aerosol number. Accumulation mode particles dominate the number size, surface area, and volume distributions. The variability of optical and physical aerosol parameters was analyzed on horizontal scales of similar to 1-4 km. There was little horizontal variability in the single-scattering albedo (w(0)), aerosol optical depth (AOD), and accumulation mode size, but greater variability in particle number concentration. Comparisons of the airborne measurements with remotely sensed aerosol parameters, such as omega(0) and effective particle radius (r(etf)), derived from the Multiangle Imaging Spectroradiometer (MISR) aboard the Terra satellite were generally in good agreement. Overall, the MISR retrievals captured both the similarities and the differences between the properties of the aerosols measured on 17 July and 2 August. C1 Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Reidmiller, DR (reprint author), Univ Washington, Dept Atmospher Sci, Box 351640, Seattle, WA 98195 USA. EM dreidm@atmos.washington.edu RI Kahn, Ralph/D-5371-2012 OI Kahn, Ralph/0000-0002-5234-6359 NR 50 TC 7 Z9 9 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAR PY 2006 VL 63 IS 3 BP 785 EP 814 DI 10.1175/JAS3674.1 PG 30 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031WM UT WOS:000236735900001 ER PT J AU Sharon, TM Albrecht, BA Jonsson, HH Minnis, P Khaiyer, MM van Reken, TM Seinfeld, J Flagan, R AF Sharon, TM Albrecht, BA Jonsson, HH Minnis, P Khaiyer, MM van Reken, TM Seinfeld, J Flagan, R TI Aerosol and cloud microphysical characteristics of rifts and gradients in maritime stratocumulus clouds SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID MARINE STRATOCUMULUS; BOUNDARY-LAYER; POLLUTION; DRIZZLE; ALBEDO AB A cloud rift is characterized as a large-scale, persistent area of broken, low-reflectivity stratocumulus clouds usually surrounded by a solid deck of stratocumulus. A rift observed off the coast of California was investigated using an instrumented aircraft to compare the aerosol, cloud microphysical, and thermodynamic properties in the rift with those of the surrounding solid stratocumulus deck. The microphysical characteristics in the solid stratocumulus deck differ substantially from those of a broken, cellular rift where cloud droplet concentrations are a factor of 2 lower than those in the solid cloud. Furthermore, cloud condensation nuclei (CCN) concentrations were found to be about 3 times greater in the solid-cloud area compared with those in the rift. Although drizzle was observed near cloud top in parts of the solid stratocumulus cloud, the largest drizzle rates were associated with the broken clouds within the rift area and with extremely large effective droplet sizes retrieved from satellite data. Minimal thermodynamic differences between the rift and solid cloud deck were observed. In addition to marked differences in particle concentrations, evidence of a mesoscale circulation near the solid cloud-rift boundary is presented. This mesoscale circulation may provide a mechanism for maintaining a rift, but further study is required to understand the initiation of a rift and the conditions that may cause it to fill. A review of results from previous studies indicates similar microphysical characteristics in rift features sampled serendipitously. These observations indicate that cloud rifts are depleted of aerosols through the cleansing associated with drizzle and are a manifestation of natural processes occurring in marine stratocumulus. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Meteorol & Phys Oceanog, Miami, FL 33149 USA. Ctr Interdisciplinary Remotely Piloted Aircraft S, Marina, CA USA. NASA, Langley Res Ctr, Sci Directorate, Hampton, VA 23665 USA. AS&M Inc, Hampton, VA USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. CALTECH, Pasadena, CA 91125 USA. RP Albrecht, BA (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Meteorol & Phys Oceanog, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. EM balbrecht@rsmas.miami.edu RI Minnis, Patrick/G-1902-2010 OI Minnis, Patrick/0000-0002-4733-6148 NR 27 TC 56 Z9 56 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAR PY 2006 VL 63 IS 3 BP 983 EP 997 DI 10.1175/JAS3667.1 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031WM UT WOS:000236735900011 ER PT J AU Stolarski, RS Douglass, AR Steenrod, S Pawson, S AF Stolarski, RS Douglass, AR Steenrod, S Pawson, S TI Trends in stratospheric ozone: Lessons learned from a 3D chemical transport model SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID INITIATIVE 3-DIMENSIONAL MODEL; DYNAMICAL CONTRIBUTIONS; HIGH-LATITUDE; COLUMN OZONE; TEMPERATURE; CIRCULATION; WINTER; FLUX; TROPOSPHERE; SIMULATIONS AB Stratospheric ozone is affected by external factors such as chlorofluorcarbons (CFCs), volcanoes, and the 11-yr solar cycle variation of ultraviolet radiation. Dynamical variability due to the quasi-biennial oscillation and other factors also contribute to stratospheric ozone variability. A research focus during the past two decades has been to quantify the downward trend in ozone due to the increase in industrially produced CFCs. During the coming decades research will focus on detection and attribution of the expected recovery of ozone as the CFCs are slowly removed from the atmosphere. A chemical transport model (CTM) has been used to simulate stratospheric composition for the past 30 yr and the next 20 yr using 50 yr of winds and temperatures from a general circulation model (GCM). The simulation includes the solar cycle in ultraviolet radiation, a representation of aerosol surface areas based on observations including volcanic perturbations from El Chichon in 1982 and Pinatubo in 1991, and time-dependent mixing ratio boundary conditions for CFCs, halons, and other source gases such as N2O and CH4. A second CTM simulation was carried out for identical solar flux and boundary conditions but with constant "background" aerosol conditions. The GCM integration included an online ozonelike tracer with specified production and loss that was used to evaluate the effects of interannual variability in dynamics. Statistical time series analysis was applied to both observed and simulated ozone to examine the capability of the analyses for the determination of trends in ozone due to CFCs and to separate these trends from the solar cycle and volcanic effects in the atmosphere. The results point out several difficulties associated with the interpretation of time series analyses of atmospheric ozone data. In particular, it is shown that lengthening the dataset reduces the uncertainty in derived trend due to interannual dynamic variability. It is further shown that interannual variability can make it difficult to accurately assess the impact of a volcanic eruption, such as Pinatubo, on ozone. Such uncertainties make it difficult to obtain an early proof of ozone recovery in response to decreasing chlorine. C1 NASA, Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Greenbelt, MD 20771 USA. Sci Syst Applicat Inc, Lanham, MD USA. NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Code 613-3, Greenbelt, MD 20771 USA. EM stolar@polska.gsfc.nasa.gov RI Douglass, Anne/D-4655-2012; Steenrod, Stephen/H-2218-2012; Stolarski, Richard/B-8499-2013; Pawson, Steven/I-1865-2014 OI Stolarski, Richard/0000-0001-8722-4012; Pawson, Steven/0000-0003-0200-717X NR 48 TC 65 Z9 65 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 EI 1520-0469 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAR PY 2006 VL 63 IS 3 BP 1028 EP 1041 DI 10.1175/JAS3650.1 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031WM UT WOS:000236735900014 ER PT J AU Ting, MF Wang, HL AF Ting, MF Wang, HL TI The role of the north American topography on the maintenance of the great plains summer low-level jet SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID CENTRAL UNITED-STATES; STATIONARY WAVES; MOISTURE TRANSPORT; DIURNAL-VARIATIONS; SEASONAL CYCLE; WARM-SEASON; PRECIPITATION; SIMULATIONS; REANALYSIS; ATMOSPHERE AB Summer precipitation over the central United States depends strongly on the strength of the Great Plains low-level jet (LLJ). The Geophysical Fluid Dynamics Laboratory's new generation of the atmospheric general circulation model (GCM) and the linear and nonlinear stationary wave models are used in this study to examine the role of North American topography in maintaining the Great Plains summer mean LLJ and precipitation. Atmospheric GCM experiments were first performed with and without the North American topography and with prescribed climatological sea surface temperatures. Results show that the Great Plains LLJ disappears completely in the experiment when the North American topography is removed, while the summer seasonal mean LLJ is well simulated in the experiment with full earth topography. In the absence of the North American topography, the summer precipitation is significantly reduced over the central United States and increased along the Gulf States and northeast Mexico. Linear and nonlinear stationary wave models are used to determine the physical mechanisms through which the North American topography maintains the Great Plains time mean LLJ. Possible mechanisms include the physical blocking of the topography and the induced flow over and around the mountains, the thermal effect due to the elevation of the topography, and the transient thermal and vorticity forcing due to the modification of transient eddy activities in the presence of the topography. The linear and nonlinear model results indicate that the dominant mechanism for maintaining the time mean Great Plains LLJ is through the nonlinear effect of the trade wind along the southern flank of the North Atlantic subtropical high encountering the east slope of the Sierra Oriental and causing the flow to turn northward. As the flow turns north along the east slope of the North American topography, it obtains anticyclonic shear vorticity and thus the LLJ. The effect of the thermal forcing is negligible, while the effect of transient forcing is only important in extending the jet farther northward and eastward. The results suggest that variations in the strength of the North Atlantic subtropical anticyclone and the associated trade wind over the Caribbean Sea and the Gulf of Mexico may be important for understanding the interannual variation of the Great Plains LLJ and U.S. precipitation. C1 Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP Ting, MF (reprint author), Columbia Univ, Lamont Doherty Earth Observ, Route 9W, Palisades, NY 10964 USA. EM ting@ldeo.columbia.edu NR 34 TC 32 Z9 33 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD MAR PY 2006 VL 63 IS 3 BP 1056 EP 1068 DI 10.1175/JAS3664.1 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 031WM UT WOS:000236735900016 ER PT J AU Roelke, DL Cotner, JB Montoya, JV Del Castillo, CE Davis, SE Snider, JA Gable, GM Winemiller, KO AF Roelke, DL Cotner, JB Montoya, JV Del Castillo, CE Davis, SE Snider, JA Gable, GM Winemiller, KO TI Optically determined sources of allochthonous organic matter and metabolic characterizations in a tropical oligotrophic river and associated lagoon SO JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY LA English DT Article DE excitation-emission matrices; absorption spectra; allochthonous; autochthonous; carbon; neotropical; Cinaruco River; lagoon ID AUTOTROPHIC CARBON-SOURCES; AMAZON RIVER; ORINOCO RIVER; FLUORESCENCE SPECTROSCOPY; FLOODPLAIN WATERS; DISSOLVED-OXYGEN; ENERGY-SOURCES; FOOD WEBS; SYSTEM; LAKES AB The Cinaruco River, an oligotrophic ecosystem in the Venezuelan llanos (savanna), has strong seasonal hydrology and supports large populations of ecologically diverse fishes. The relative contributions of autochthonous and allochthonous production sources that support high stocks of secondary consumers are undetermined in this river. We used excitation-emission fluorescence spectroscopy and absorption spectra of dissolved organic matter to infer degradation of leaf material originating from the surrounding gallery forest. During the low-water period, a large fraction of fluorescent organic matter contained in leaves degraded quickly in river water and was an important allochthonous contribution of C to the system. However, the fluorescence signature of dissolved organic matter in lagoons was different from that of the main river channel during the falling-water period, suggesting that other sources of C were present. Allochthonous organic matter clearly fueled microbial respiration during the falling-water period, but our in-water experiments using light-dark bottle methods indicated that autochthonous production was an important supplementary C source in shallow nearshore waters. During the low-water and falling-water periods, water-column primary production in nearshore waters ranged from 150 to 500 mg C m(-2) d(-1) and was 2x greater than community respiration, i.e., the nearshore component of the water column was net autotrophic. Benthic primary production in nearshore areas where light reached the sediments ranged between 350 and 500 mg C m(-2) d-' and was about equal to community respiration. Primary production was probably limited by the availability of dissolved inorganic N, which sometimes was below detection limits of similar to 0.5 mu M (mean similar to 0.25 mu M). Our results support the idea that autotrophic production is an important C source in neotropical rivers. C1 Texas A&M Univ, Dept Wildlife & Fisheries Sci, Sect Ecol Evolutionary Biol & Systemat, College Stn, TX 77843 USA. Texas A&M Univ, Dept Oceanog, College Stn, TX 77843 USA. Univ Minnesota, Dept Ecol Evolut & Behav, St Paul, MN 55108 USA. US Natl Aeronaut & Space Adm, Earth Sci Applicat Directorate, Stennis Space Ctr, MS 39529 USA. RP Roelke, DL (reprint author), Texas A&M Univ, Dept Wildlife & Fisheries Sci, Sect Ecol Evolutionary Biol & Systemat, 2258 TAMU, College Stn, TX 77843 USA. EM droelke@tamu.edu; cotne002@umn.edu; jvmontoya@tamu.edu; carlos.e.delcastillo@nasa.gov; sedavis@tamu.edu; jensnider1230@hotmail.com; gotgame26@hotmail.com; k-winemiller@tamu.edu RI Montoya, Jose/A-6775-2008; Roelke, Daniel/B-5766-2008; Del Castillo, Carlos/N-2601-2013; OI Montoya, Jose/0000-0002-9759-4946; Winemiller, Kirk/0000-0003-0236-5129 NR 63 TC 14 Z9 15 U1 1 U2 11 PU NORTH AMER BENTHOLOGICAL SOC PI LAWRENCE PA 1041 NEW HAMSPHIRE STREET, LAWRENCE, KS 66044 USA SN 0887-3593 J9 J N AM BENTHOL SOC JI J. N. Am. Benthol. Soc. PD MAR PY 2006 VL 25 IS 1 BP 185 EP 197 DI 10.1899/0887-3593(2006)25[185:ODSOAO]2.0.CO;2 PG 13 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 029LX UT WOS:000236565400015 ER PT J AU Stanford, MK DellaCorte, C AF Stanford, MK DellaCorte, C TI Effects of humidity on the flow characteristics of a composite plasma spray powder SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE APS coatings; composite materials processing; feedstock production/preparation technology; powder flowability; relative humidity AB The effects of environmental humidity on the flow characteristics of a multicomponent (composite) plasma spray powder have been investigated. Angular and spherical BaF2-CaF2 powder was fabricated by comminution and by atomization, respectively. The fluorides were blended with nichrome, chromia, and silver powders to produce a composite plasma spray feedstock. The tap density, apparent density, and angle of repose were measured at 50% relative humidity (RH). The flow of the powder was studied from 2 to 100% RH. The results suggest that the feedstock flow is only slightly degraded with increasing humidity below 66% RH and is more affected above 66% RH. There was no flow above 90% RH except with narrower particle size distributions of the angular fluorides, which allowed flow up to 95% RH. These results offer guidance that enhances the commercial potential for this material system. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Stanford, MK (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM Malcolm.K.Stanford@nasa.gov NR 11 TC 2 Z9 2 U1 0 U2 3 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD MAR PY 2006 VL 15 IS 1 BP 33 EP 36 DI 10.1361/105996306X92550 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA 020GU UT WOS:000235897500010 ER PT J AU Wilson, SG Polovina, JJ Stewart, BS Meekan, MG AF Wilson, SG Polovina, JJ Stewart, BS Meekan, MG TI Movements of whale sharks (Rhincodon typus) tagged at Ningaloo Reef, Western Australia SO MARINE BIOLOGY LA English DT Article ID TUNA THUNNUS-THYNNUS; ATLANTIC BLUEFIN TUNA; SOUTHERN CALIFORNIA BIGHT; SEA-SURFACE-TEMPERATURE; ARCHIVAL TAGS; PSEUDEUPHAUSIA-LATIFRONS; ALOPIAS-SUPERCILIOSUS; HORIZONTAL MOVEMENTS; DEPTH PREFERENCES; HABITAT SELECTION AB Whale sharks (Rhincodon typus Smith) aggregate seasonally (March-June) to feed in coastal waters off Ningaloo Reef, Western Australia. Pop-up archival tags were attached to 19 individuals (total lengths 4.5-11.0 m) at this location in early May of 2003 and 2004 to examine their horizontal and vertical movements. The long-term movement patterns of six whale sharks were documented, all of which travelled northeast into the Indian Ocean after departing Ningaloo Reef. They used both inshore and offshore habitats and made extensive vertical movements, occasionally to a depth of at least 980 m. Frequent up-and-down movements, diel vertical migration, and crepuscular descents were evident in the depth records. The sharks experienced ambient temperatures ranging between 4.2 and 28.7 degrees C and encountered gradients of up to 20.8 degrees C on dives. C1 Univ New Hampshire, Dept Zool, Durham, NH 03824 USA. Hubbs SeaWorld Res Inst, San Diego, CA 92109 USA. Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu, HI 96822 USA. Australian Inst Marine Sci, Darwin, NT, Australia. RP Wilson, SG (reprint author), Univ New Hampshire, Dept Zool, Durham, NH 03824 USA. EM swilson@hswri.org NR 63 TC 72 Z9 78 U1 7 U2 41 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD MAR PY 2006 VL 148 IS 5 BP 1157 EP 1166 DI 10.1007/s00227-005-0153-8 PG 10 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 015JJ UT WOS:000235547400025 ER PT J AU La Via, WV Lambert, JL Pelletier, MJ Morookian, JM Sirk, SJ Mickiene, D Walsh, TJ Borchert, MS AF La Via, WV Lambert, JL Pelletier, MJ Morookian, JM Sirk, SJ Mickiene, D Walsh, TJ Borchert, MS TI Measurement of Amphotericin B concentration by Resonant Raman Spectroscopy - a novel technique that may be useful for non-invasive monitoring SO MEDICAL MYCOLOGY LA English DT Article DE Resonant Raman Spectroscopy (RRS); amphotericin B (AmB) ID LIPID FORMULATIONS; ENDOPHTHALMITIS; PENETRATION; GLUCOSE; RABBITS; MODEL AB We wished to determine whether Resonant Raman Spectroscopy (RRS) could be used to measure Amphotericin B (AmB) at therapeutic and subtherapeutic concentrations in a model system mimicking the anterior chamber of the eye. The goal was to develop a technique for non-invasive measurement of AmB levels in the aqueous humor (AH) of the eye. A krypton-ion laser source (406.7 nm) was used for excitation and Resonant Raman Spectra were captured with a confocal system in an anterior chamber (AC) model. These spectra were used to develop a correlation curve for prediction of AmB levels. Subsequently, one rabbit was evaluated with this system after 5 days of intravenous AmB administration (1 mg/kg/day) and AmB concentrations measured by RRS were compared to those measured by high-performance liquid chromatography (HPLC). AmB exhibited a unique spectral peak at 1557 cm(-1). Integrated area of this peak linearly correlated with AmB concentration in our model AC. When integrated peak area from multiple in vivo measurements in one animal at steady-state was plotted on this correlation curve, we were able to predict AmB levels. These closely approximated those measured by HPLC. These measurements were not significantly affected by photobleaching or depth profile at acquisition. RRS at 406.7 ran is a method that may be useful for non-invasive monitoring of intraocular AmB levels. This instrument can help physicians decide when repeat, invasive delivery of this drug is warranted based on Measurement of actual drug levels in the AH. Also, there is the potential to measure the ocular concentrations of other pharmaceutical agents with similar instruments. C1 Univ So Calif, Keck Sch Med, Div Infect Dis, Childrens Hosp Los Angeles, Los Angeles, CA 90027 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ So Calif, Keck Sch Med, Div Ophthalmol, Childrens Hosp Los Angeles, Los Angeles, CA USA. NCI, Pediat Oncol Branch, Immunocompromised Host Sect, Bethesda, MD 20892 USA. RP La Via, WV (reprint author), Univ So Calif, Keck Sch Med, Div Infect Dis, Childrens Hosp Los Angeles, 4650 W Sunset Blvd,MS 51, Los Angeles, CA 90027 USA. EM wlavia@chla.usc.edu NR 15 TC 12 Z9 12 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1369-3786 J9 MED MYCOL JI Med. Mycol. PD MAR PY 2006 VL 44 IS 2 BP 169 EP 174 DI 10.1080/13693780500338761 PG 6 WC Infectious Diseases; Mycology; Veterinary Sciences SC Infectious Diseases; Mycology; Veterinary Sciences GA 013VQ UT WOS:000235438500009 PM 16519020 ER PT J AU Wier, LT Jackson, AS Ayers, GW Arenare, B AF Wier, LT Jackson, AS Ayers, GW Arenare, B TI Nonexercise models for estimating VO2max with waist girth, percent fat, or BMI SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Article DE aerobic power; prediction models; circumference; body composition ID BODY-MASS INDEX; GENERALIZED EQUATIONS; CARDIORESPIRATORY FITNESS; AEROBIC CAPACITY; MEN; EXERCISE; DENSITY; WOMEN; MORTALITY; FEMALES AB Previously published nonexercise models using either percent fat or body mass index (BMI) as body composition measures provided valid estimates of (V) over dot O-2max. Purpose: This study was conducted to investigate the use of waist girth (WG) as a body composition surrogate in the nonexercise models and to compare the accuracy of nonexercise models that include WG, %fat, or BMI. Methods: A total of 2417 men and 384 women were measured for (V)over dotO(2max) by indirect calorimetry (RER > 1.1); age (yr); gender by M = 1 W = 0; self-report activity habit by the 11-point (0-10) NASA physical activity status scale (PASS); WG at the apex of the umbilicus; %fat by skinfolds; and BMI by weight (kg) divided by height squared (m(2)). Results: Three models were developed by multiple regression to estimate (V)over dotO(2max) from age, gender, PASS, and either WG (R = 0.81. standard error of estimate (SEE) = 4.80 mL center dot kg(-1)center dot min(-1)),%fat (R = 0.82, SEE = 4.72 mL center dot kg(-1)center dot min(-1)), or BMI (R = 0.80, SEE = 4.90 mL center dot kg(-1)center dot min(-1)). Cross-validation by the PRESS technique confirmed these statistics. Accuracy of the models for predicting (V)over dotO(2max) of subsamples was supported by constant errors (CE) < 1 mL center dot kg(-1)-min(-1) for subgroups of gender, age, PASS, and (V)over dotO(2max) between 30 and 50 mL center dot kg(-1)center dot min(-1) (70% of the sample). CE were > 1 mL center dot kg(-1)center dot min(-1) for (V)over dotO(2max) < 30 and > 50 mL center dot kg(-1)center dot min(-1). Conclusions: Waist girth is an acceptable surrogate for body composition in the nonexercise models. All models were similar in accuracy and valid for estimating (V)over dotO(2max) of most adults, but with reduced accuracy at the extremes of fitness ((V)over dotO(2max) < 30 and > 50 mL center dot kg(-1)center dot min(-1)). C1 NASA, Johnson Space Ctr, Kelsey Seybold Clin, Houston, TX 77058 USA. Univ Houston, Houston, TX USA. RP Wier, LT (reprint author), 16027 Windom, Webster, TX 77578 USA. EM larry.t.wier1@nasa.jsc.gov NR 34 TC 31 Z9 32 U1 0 U2 4 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 MAR PY 2006 VL 38 IS 3 BP 555 EP 561 DI 10.1249/01.mss.0000193561.64152 PG 7 WC Sport Sciences SC Sport Sciences GA 023OJ UT WOS:000236135800022 PM 16540845 ER PT J AU Barr, P Zaman, A Miranda, F AF Barr, P Zaman, A Miranda, F TI A compact, broadband antenna for planetary surface-to-surface wireless communications SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE compact; broadband antennas; planetary surface-to-surface communications; tri-lobed patch AB The compact microstrip monopole antenna (CMMA) is a novel antenna design that combines a microstrip patch antenna with a 3D structure to attain a highly directive, broadband, compact antenna. A tri-lobed patch (TLP) is designed to minimize the patch's area while reducing the antenna's operating frequency. A grounding wall (GW) connects the patch to the ground plane and a vertical-enclosure wall (VEW) extends up, away from portions of the patch's perimeter. This VEW supplies the antenna with a higher directivity in the radial direction and also reduces the operating frequency. The CMMA was designed to operate at 2.23 GHz, but experimental results have shown this antenna resonates at 2.05 GHz which is on the order of approximately lambda(0)/11.6 with respect to the antenna's largest dimension, with a directivity and bandwidth of 6.0 dBi and 130 MHz (6.3%), respectively. This miniature, radially and emitting antenna makes the CMMA attractive for planetary-based surface-to-surface communications. (c) 2006 Wiley Periodicals, Inc. C1 Glenn Res Ctr, Natl Aeronaut & Space Adm, Antenna Microwave & Opt Syst Branch, Cleveland, OH 44135 USA. RP Barr, P (reprint author), Glenn Res Ctr, Natl Aeronaut & Space Adm, Antenna Microwave & Opt Syst Branch, Cleveland, OH 44135 USA. NR 8 TC 0 Z9 0 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 MAR PY 2006 VL 48 IS 3 BP 521 EP 524 DI 10.1002/mop.21397 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 017GF UT WOS:000235681400032 ER PT J AU Aberson, SD Halverson, JB AF Aberson, SD Halverson, JB TI Kelvin-Helmholtz billows in the eyewall of Hurricane Erin SO MONTHLY WEATHER REVIEW LA English DT Article ID INSTABILITY AB A photograph of vertically aligned Kelvin-Helmholtz billows in the eastern eyewall of Hurricane Erin on 10 September 2001 is presented. The vertical shear instability in the horizontal winds necessary to produce the billows is confirmed with a high-altitude dropwindsonde observation. This shear instability is not known to be common in tropical cyclone eyewalls and is likely only in cases with a very large eyewall tilt. However, research and reconnaissance aircraft pilots need to be aware of: the possibility of their existence, along with other types of hazardous conditions, in such rare circumstances. C1 NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, Miami, FL 33149 USA. NASA, Goddard Space Flight Ctr, Joint Ctr Earth Syst Technol, Greenbelt, MD 20771 USA. RP NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, 4301 Rickenbacker Causeway, Miami, FL 33149 USA. EM sim.aberson@noaa.gov RI Aberson, Sim/C-4891-2013 OI Aberson, Sim/0000-0002-3670-0100 NR 5 TC 4 Z9 4 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 2006 VL 134 IS 3 BP 1036 EP 1038 DI 10.1175/MWR3094.1 PG 3 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 033LB UT WOS:000236848200016 ER PT J AU Wu, AM Hsieh, WW Tang, BY AF Wu, AM Hsieh, WW Tang, BY TI Neural network forecasts of the tropical Pacific sea surface temperatures SO NEURAL NETWORKS LA English DT Article; Proceedings Paper CT IEEE International Joint Conference on Neural Networks (IJCNN 2005) CY JUL 31-AUG 04, 2005 CL Montreal, CANADA SP Int Neural Network Soc, IEEE Computat Intelligence Soc DE neural network; El Nino; ENSO; nonlinear; forecast; sea surface temperature; tropical Pacific ID CANONICAL CORRELATION-ANALYSIS; LEVEL PRESSURE; WIND STRESS; ENSO; PREDICTION; MODELS; TOGA AB A nonlinear forecast system for the sea Surface temperature (SST) anomalies over the whole tropical Pacific has been developed using a multilayer perceptron neural network approach, where sea level pressure and SST anomalies were used as predictors to predict the five leading SST principal components at lead times from 3 to 15 months. Relative to the linear regression (LR) models, the nonlinear (NL) models showed higher correlation skills and lower root mean square errors over most areas of the domain, especially over the far western Pacific (west of 155 degrees E) and the eastern equatorial Pacific off Peru at lead times loner than 3 months, with correlation skills enhanced by 0.10-0.14. Seasonal and decadal changes in the prediction skills in the NL and LR models were also studied. (c) 2006 Elsevier Ltd. All rights reserved. C1 Univ British Columbia, Dept Earth & Ocean Sci, Vancouver, BC V6T 1Z4, Canada. Jet Propuls Lab, Pasadena, CA USA. RP Hsieh, WW (reprint author), Univ British Columbia, Dept Earth & Ocean Sci, 6339 Stores Rd, Vancouver, BC V6T 1Z4, Canada. EM whsieh@eos.ubc.ca RI Hsieh, William/G-8380-2011 OI Hsieh, William/0000-0003-2654-392X NR 19 TC 24 Z9 25 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0893-6080 J9 NEURAL NETWORKS JI Neural Netw. PD MAR PY 2006 VL 19 IS 2 BP 145 EP 154 DI 10.1016/j.neunet.2006.01.004 PG 10 WC Computer Science, Artificial Intelligence SC Computer Science GA 042KU UT WOS:000237527600005 PM 16527455 ER PT J AU Windhorst, RA Cameron, RA Brissenden, RJ Elvis, MS Fabbiano, G Gorenstein, P Reid, PB Schwartz, DA Bautz, MW Figueroa-Feliciano, E Petre, R White, NE Zhang, WW AF Windhorst, RA Cameron, RA Brissenden, RJ Elvis, MS Fabbiano, G Gorenstein, P Reid, PB Schwartz, DA Bautz, MW Figueroa-Feliciano, E Petre, R White, NE Zhang, WW TI Generation-X: An X-ray observatory designed to observe first light objects SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT First Light and Reionization - Theoretical Study and Experimental Detection of First Luminous Sources in the Universe CY MAY 18-21, 2005 CL Irvine, CA DE Gen-X; vision mission; X-ray astronomy; active optics; lightweight optics ID STAR-FORMATION RATE; FIELD NORTH SURVEY; SOURCE CATALOGS; BLACK-HOLES; GALAXIES; BINARIES AB The new cosmological frontier will be the study of the very first stars, galaxies and black holes in the early Universe. These objects are invisible to the current generation of X-ray telescopes, such as Chandra. In response, the Generation-X ('' Gen-X '') Vision Mission has been proposed as a future X-ray observatory which will be capable of detecting the earliest objects. X-ray imaging and spectroscopy of such faint objects demands a large collecting area and high angular resolution. The Gen-X mission plans 100 m(2) collecting area at 1 keV (1000x that of Chandra), and with an angular resolution of 0.1 ''. The Gen-X mission will operate at Sun-Earth L2, and might involve four 8 m diameter telescopes or even a single 20 m diameter telescope. To achieve the required effective area with reasonable mass, very lightweight grazing incidence X-ray optics must be developed, having an areal density 100x lower than in Chandra, with mirrors as thin as 0.1 mm requiring active on-orbit figure control. The suite of available detectors for Gen-X should include a large-area high resolution imager, a cryogenic imaging spectrometer, and a grating spectrometer. We discuss use of Gen-X to observe the birth of the first black holes, stars and galaxies, and trace their cosmic evolution. (c) 2005 Elsevier B.V. All rights reserved. C1 Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Windhorst, RA (reprint author), Arizona State Univ, Dept Phys & Astron, Box 871504, Tempe, AZ 85287 USA. EM Rogier.Windhorst@asu.edu RI White, Nicholas/B-6428-2012 OI White, Nicholas/0000-0003-3853-3462 NR 22 TC 20 Z9 20 U1 2 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD MAR PY 2006 VL 50 IS 1-3 BP 121 EP 126 DI 10.1016/j.newar.2005.11.019 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018ET UT WOS:000235747500020 ER PT J AU Yan, HJ Dickinson, M Stern, D Eisenhardt, PRM Chary, RR Giavalisco, M Ferguson, HC Casertano, S Conselice, CJ Papovich, C Reach, WT Grogin, N Moustakas, LA Ouchi, M AF Yan, HJ Dickinson, M Stern, D Eisenhardt, PRM Chary, RR Giavalisco, M Ferguson, HC Casertano, S Conselice, CJ Papovich, C Reach, WT Grogin, N Moustakas, LA Ouchi, M TI GOODS spitzer IRAC observations of high-z galaxies - Implications for reionization SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT First Light and Reionization - Theoretical Study and Experimental Detection of First Luminous Sources in the Universe CY MAY 18-21, 2005 CL Irvine, CA DE cosmology : observations; galaxies : evolution; galaxies : luminosity function; mass function; infrared : galaxies ID ULTRA-DEEP-FIELD; STAR-FORMATION RATE; SPACE-TELESCOPE; HIGH-REDSHIFT; DATA REDUCTION; UNIVERSE; CAMERA; Z-APPROXIMATE-TO-6; GRISM AB A significant number of Lyman-break galaxies (LBGs) at z approximate to 6 and 5 in the Hubble Ultradeep Field (HUDF) have been detected by the Great Observatories Origins Deep Survey (GOODS) observations with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We find that the SEDs for many of these IRAC-detected high-z galaxies are best fitted by models of stellar populations with masses of a few x 10(10) M-Theta, and with ages of a few hundred million years. This implies that at least some of the galaxies that are responsible for finishing reionization at z approximate to 6 started forming their stars at z > 7 and earlier. The lower limits to the space density for higb-z galaxies in this mass range are consistent with predictions from recent hydrodynamic simulations of structure formation in a Lambda CDM universe. All objects in our samples are consistent with having solar metallicity, suggesting that the sources that contributed ionizing photons at z approximate to 6 might not be comprised of '' first stars ''. Some of these galaxies have rest-frame UV colors that are bluer than those predicted by the stellar population models to which we compare them, and can be explained by the presence of very massive stars (> 100 M-Theta). This suggests that very massive stars might play an important role in producing ionizing photons in the early stage of the universe. The analysis of z approximate to 6 LBGs has been extended to the entire GOODS fields, HDF-N and CDF-S, and we report the preliminary results. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, Pasadena, CA 91125 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Yan, HJ (reprint author), CALTECH, Spitzer Sci Ctr, M-S 220-6, Pasadena, CA 91125 USA. EM yhj@ipac.caltech.edu RI Ouchi, Masami/A-4490-2011; Conselice, Christopher/B-4348-2013; OI Conselice, Christopher/0000-0003-1949-7638; Moustakas, Leonidas/0000-0003-3030-2360; Reach, William/0000-0001-8362-4094 NR 21 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD MAR PY 2006 VL 50 IS 1-3 BP 127 EP 133 DI 10.1016/j.newar.2005.11.026 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018ET UT WOS:000235747500021 ER PT J AU Kashlinsky, A AF Kashlinsky, A TI Cosmic infrared background and early stellar populations SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT First Light and Reionization - Theoretical Study and Experimental Detection of First Luminous Sources in the Universe CY MAY 18-21, 2005 CL Irvine, CA DE cosmic infrared background; population III stars; reionization; galaxy formation; galaxy evolution ID SPITZER-SPACE-TELESCOPE; COBE DIRBE MAPS; ALL-SKY SURVEY; TENTATIVE DETECTION; EXPERIMENT SEARCH; SOURCE COUNTS; FLUCTUATIONS; EMISSION; LIGHT; ANISOTROPIES AB Cosmic infrared background (CIB) contains information about galaxy luminosities over the entire history of the Universe and can be a powerful diagnostic of the early populations otherwise inaccessible to telescopic studies. Its measurements are very difficult because of the strong IR foregrounds from the Solar system and the Galaxy. Nevertheless, substantial recent progress in measuring the CIB and its structure has been made. The measurements now allow to set significant constraints on early galaxy evolution and, perhaps, even detect the elusive Population III era. We discuss briefly the theory behind the CIB, review the latest measurements of the CIB and its structure, and discuss their implications for detecting and/or constraining the first stars and their epochs. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, SSAI, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 USA. RP Kashlinsky, A (reprint author), NASA, Goddard Space Flight Ctr, SSAI, Greenbelt, MD 20771 USA. EM kashlinsky@stars.gsfc.nasa.gov NR 29 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD MAR PY 2006 VL 50 IS 1-3 BP 208 EP 214 DI 10.1016/j.newar.2005.11.017 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018ET UT WOS:000235747500034 ER PT J AU Bock, J Battle, J Cooray, A Kawada, M Keating, B Lange, A Lee, DH Matsumoto, T Matsuura, S Pak, S Renbarger, T Sullivan, T Tsumura, K Wada, T Watabe, T AF Bock, J Battle, J Cooray, A Kawada, M Keating, B Lange, A Lee, DH Matsumoto, T Matsuura, S Pak, S Renbarger, T Sullivan, T Tsumura, K Wada, T Watabe, T TI The cosmic infrared background experiment SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT First Light and Reionization - Theoretical Study and Experimental Detection of First Luminous Sources in the Universe CY MAY 18-21, 2005 CL Irvine, CA DE extragalactic background; primordial galaxies; infrared ID BRIGHTNESS FLUCTUATIONS; EXPERIMENT SEARCH; ZODIACAL LIGHT; 1ST DETECTIONS; 8000 ANGSTROM; MICRONS; DIRBE; ANISOTROPIES; TELESCOPE; COUNTS AB The extragalactic background, based on absolute measurements reported by DIRBE and IRTS at 1.2 and 2.2 mu m, exceeds the brightness derived from galaxy counts by up to a factor 5. Furthermore, both DIRBE and the IRTS report fluctuations in the near-infrared sky brightness that appear to have an extra-galactic origin, but are larger than expected from local (z = 1-3) galaxies. These observations have led to speculation that a new class of high-mass stars or mini-quasars may dominate primordial star formation at high-redshift (z similar to 10-20), which.. in order to explain the excess in the near-infrared background, must be highly luminous but produce a limited amount of metals and X-ray photons. Regardless of the nature of the sources, if a significant component of the near-infrared background comes from first-light galaxies, theoretical models generically predict a prominent near-infrared spectral feature from the redshifted Lyman cutoff, and a distinctive fluctuation power spectrum. We are developing a rocket-borne instrument (the Cosmic Infrared Background ExpeRiment, or CIBER) to search for signatures of primordial galaxy formation in the cosmic near-infrared extra-galactic background. CIBER consists of a wide-field two-color camera, a low-resolution absolute spectrometer, and a high-resolution narrow-band imaging spectrometer. The cameras will search for spatial fluctuations in the background on angular scales from 7 '' to 2 degrees, where a first-light galaxy signature is expected to peak, over a range of angular scales poorly covered by previous experiments. CIBER will determine if the fluctuations reported by the IRTS arise from first-light galaxies or have a local origin. In a short rocket flight CIBER has sensitivity to probe fluctuations 100x fainter than IRTS/DIRBE, with sufficient resolution to remove local-galaxy correlations. By jointly observing regions of the sky studied by Spitzer and ASTRO-F, CIBER will build a multi-color view of the near-infrared background, accurately assessing the contribution of local (7 = 1-3) galaxies to the observed background fluctuations, allowing a deep and comprehensive survey for first-light galaxy background fluctuations. The low-resolution spectrometer will search for a redshifted Lyman cutoff feature between 0.8 and 2.0 mu m. The high-resolution spectrometer will trace zodiacal light using the intensity of scattered Fraunhofer lines, providing an independent measurement of the zodiacal emission and a new check of DIRBE zodiacal dust models. The combination will systematically search for the infrared excess background light reported in near-infrared DIRBE/IRTS data, compared with the small excess reported at optical wavelengths. (c) 2005 Published by Elsevier B.V. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Nagoya Univ, Chikusa Ku, Nagoya, Aichi 4648602, Japan. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Korea Astron & Space Sci Inst, Taejon 305348, South Korea. JAXA, ISAS, Sagamihara, Kanagawa 2298510, Japan. RP Bock, J (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM James.Bock@jpl.nasa.gov RI Pak, Soojong/E-2360-2013; Matsuura, Shuji/B-5658-2016; OI Matsuura, Shuji/0000-0002-5698-9634; Pak, Soojong/0000-0002-2548-238X NR 29 TC 22 Z9 22 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD MAR PY 2006 VL 50 IS 1-3 BP 215 EP 220 DI 10.1016/j.newar.2005.11.034 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018ET UT WOS:000235747500035 ER PT J AU Bradford, CM Nakagawa, T AF Bradford, CM Nakagawa, T CA BLISS-SPICA Team TI The future is BLISS - sensitive far-IR spectroscopy on SPICA and SAFIR SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT First Light and Reionization - Theoretical Study and Experimental Detection of First Luminous Sources in the Universe CY MAY 18-21, 2005 CL Irvine, CA DE far-IR; submillimeter; spectroscopy; SPICA; SAFIR ID WARM MOLECULAR GAS; M82; EMISSION AB Half the energy produced since decoupling emerges in the far-IR, hence a complete understanding of the history of stellar nucleosynthesis and galaxy evolution requires a systematic study of dust-enshrouded energy release at all epochs. Sensitive far-IR spectroscopy is the natural tool for this, and we present the first opportunity for cosmological far-IR spectroscopy with new cryogenic telescopes and instruments. We are studying a US-built spectrograph BLISS for the Japanese SPICA mission to launch in 2013, and NASA's SAFIR mission, envisioned for 2025. With sensitive detectors and the very low backgrounds provided by the cold telescope, we anticipate 5-8 orders of magnitude speed improvement relative to preceeding platforms, enabling measurements throughout the epoch of peak activity in galaxies, to z similar to 5. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Jet Prop Lab, Pasadena, CA USA. JAXA, ISAS, Sagamihara, Kanagawa, Japan. RP Bradford, CM (reprint author), NASA, Jet Prop Lab, Pasadena, CA USA. EM matt.bradford@jpl.nasa.gov; nakagawa@ir.isas.jaxa.jp NR 17 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD MAR PY 2006 VL 50 IS 1-3 BP 221 EP 227 DI 10.1016/j.newar.2005.11.032 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018ET UT WOS:000235747500036 ER PT J AU Harwit, M Leisawitz, D Rinehart, S AF Harwit, M Leisawitz, D Rinehart, S TI A far-infrared/submillimeter kilometer-baseline interferometer in space SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT First Light and Reionization - Theoretical Study and Experimental Detection of First Luminous Sources in the Universe CY MAY 18-21, 2005 CL Irvine, CA DE cosmology; instrumentation; interferometry; far-infrared/submillimeter AB Through the continuing development of improved detectors and detector arrays, far-infrared/submillimeter astronomical space missions have had enormous successes in recent years. Despite these advances, the diffraction-limited angular resolving power has remained virtually constant. The advent of telescopes with apertures of several meters, will improve the situation, but will still leave image resolution many orders of magnitude poorer than in most other spectral ranges. After making the scientific case for high spatial resolution imaging in this spectral range, and the use of interferometry as the most immediate way of producing results, we review the use of far-infrared/submillimeter interferometers to provide insight on the formation of the first stars. (c) 2005 Elsevier B.V. All rights reserved. C1 Cornell Univ, Ithaca, NY USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Harwit, M (reprint author), 511 H St SW, Washington, DC 20024 USA. EM harwit@verizon.net NR 6 TC 16 Z9 17 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD MAR PY 2006 VL 50 IS 1-3 BP 228 EP 234 DI 10.1016/j.newar.2005.11.030 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 018ET UT WOS:000235747500037 ER PT J AU Sarkisov, SS Curley, MJ Huey, L Fields, A Sarkisov, SS Adamovsky, G AF Sarkisov, Sergey S. Curley, Michael J. Huey, LaQuieta Fields, Aisha Sarkisov, Sergey S., II Adamovsky, Grigory TI Light-driven actuators based on polymer films SO OPTICAL ENGINEERING LA English DT Article; Proceedings Paper CT SPIE Conference on Optomechatronic Sensor, Actuators, and Control CY OCT, 2004 CL Philadelphia, PA SP SPIE DE optomechatronic actuator; photomechanical effect; optical motor; light-driven actuator; polyvinylidene fluoride ID FIBER AB We describe new light-driven actuators based on films of polymer polyvinylidene fluoride, known as PVDF. The actuators employ the photomechanic bending of the polymer film caused by low-power (10 mW and less) laser radiation. The photomechanic effect combines various physical mechanisms, such as thermal expansion, the converse piezoelectric mechanism, and the photovoltaic and pyroelectric mechanisms, while the mechanism of thermal expansion is dominant. The force applied by the actuators to external objects is measured with a torsion balance. It is proportional to the power of laser beam and could be as high as 10(-4) N for a 50-mu m film illuminated with a 10-mW laser beam. We demonstrate mechanical vibrations of a 1 x 7-mm strip actuator at a frequency of 0.3 kHz. As examples of possible applications, a photonic switch and an actuator with a closed-loop motion that could drive the inner workings of a conventional mechanical clock were demonstrated. The proposed actuators have a potential of being used as propulsion components of future light-driven micro/nano systems. (c) 2006 Society of Photo-Optical Instrumentation Engineers. C1 SSS Opt Technol LLC, Normal, AL 35762 USA. Alabama A&M Univ, Dept Phys, Normal, AL 35762 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Sarkisov, SS (reprint author), SSS Opt Technol LLC, 515 Sparkman Dr,Suite 122, Normal, AL 35762 USA. EM mazillo@hotmail.com NR 11 TC 13 Z9 13 U1 2 U2 15 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 MAR PY 2006 VL 45 IS 3 AR 034302 DI 10.1117/1.2185093 PG 10 WC Optics SC Optics GA 043SL UT WOS:000237621800024 ER PT J AU Walters, RJ Murphy, JL Rabinovich, WS Gilbreath, GC Wilt, DM Smith, MA Krasowski, MJ Jenkins, PP Scheiman, D Warner, JH Messenger, SR Lorentzen, JR Summers, GP AF Walters, RJ Murphy, JL Rabinovich, WS Gilbreath, GC Wilt, DM Smith, MA Krasowski, MJ Jenkins, PP Scheiman, D Warner, JH Messenger, SR Lorentzen, JR Summers, GP TI Photovoltaically powered modulating retroreflectors SO OPTICAL ENGINEERING LA English DT Article DE photovoltaics; quantum well modulator; optical data link AB The development of a photovoltaically (PV) powered laser communication system that constitutes a miniature, highly energy-efficient wireless communication technology is described. The technology is based on the direct integration of a multiquantum well (MQW) modulating retroreflector (MRR) optical communication node and a monolithically integrated module (MIM) PV power source. The MQW MRR optical data link exploits the shift in the MQW absorption peak under an applied reverse bias to modulate incident laser light, enabling binary encoding of data for transfer. A MIM consists of many individual solar cells monolithically integrated on a single substrate and offers the design versatility necessary to enable efficient electrical conversion of both incident sunlight and the system laser light and the ability to match the voltage output to the MRR requirements. A description of the development of the MRR and MIM components of the system is given. Results of bench-top demonstrations of the operational system are presented. (c) 2006 Society of Photo-Optical Instrumentation Engineers. C1 USN, Res Lab, Washington, DC 20375 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Cleveland, OH 44135 USA. SFA Inc, Largo, MD 20774 USA. RP Walters, RJ (reprint author), USN, Res Lab, 4555 Overlook Ave, Washington, DC 20375 USA. EM Robert.Walters@NRL.NAVY.MIL NR 6 TC 0 Z9 0 U1 0 U2 2 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 MAR PY 2006 VL 45 IS 3 AR 034003 DI 10.1117/1.2182127 PG 6 WC Optics SC Optics GA 043SL UT WOS:000237621800017 ER PT J AU Matsko, AB Savehenkov, AA Ilchenko, VS Maleki, L AF Matsko, AB Savehenkov, AA Ilchenko, VS Maleki, L TI Optical gyroscope with whispering gallery mode optical cavities (vol 233, pg 107, 2004) SO OPTICS COMMUNICATIONS LA English DT Correction C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Matsko, AB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 298-100, Pasadena, CA 91109 USA. EM Andrey.Matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 2 TC 17 Z9 19 U1 2 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAR 1 PY 2006 VL 259 IS 1 BP 393 EP 394 DI 10.1016/j.optcom.2005.08.017 PG 2 WC Optics SC Optics GA 008UY UT WOS:000235067400063 ER PT J AU Carroll, TN Gormley, TJ Bilardo, VJ Burton, RM Woodman, KL AF Carroll, TN Gormley, TJ Bilardo, VJ Burton, RM Woodman, KL TI Designing a new organization at NASA: An organization design process using simulation SO ORGANIZATION SCIENCE LA English DT Article DE organization design; NASA; simulation; process; tools; contingency theory ID STRATEGY PROCESS; FIT AB The challenge for NASA's Systems Analysis Integrated Discipline Team (SAIDT) is to develop a new organization design capable of performing complex modeling and analysis tasks. using team members at various NASA centers. The focus is on: (1) design as a process, (2) the effect of design tools on the process as well as alternative designs, (3) the fit between the tools and their fit with the organization, (4) the effect of an ongoing agencywide transformation, and (5) implications for organizational contingency theory. C1 Georgia Inst Technol, Coll Management, Atlanta, GA 30308 USA. Gormley & Associates, Irvine, CA 92620 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Duke Univ, Fuqua Sch Business, Durham, NC 27705 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Carroll, TN (reprint author), Georgia Inst Technol, Coll Management, 800 W Peachtree St NW, Atlanta, GA 30308 USA. EM tim.carroll@mgt.gatech.edu; tjgormley@cox.net; vincent.j.bilardo@grc.nasa.gov; rich.burton@duke.edu; k.l.woodman@larc.nasa.gov NR 28 TC 14 Z9 14 U1 1 U2 18 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 1047-7039 J9 ORGAN SCI JI Organ Sci. PD MAR-APR PY 2006 VL 17 IS 2 BP 202 EP 214 DI 10.1287/orsc.1050.0166 PG 13 WC Management SC Business & Economics GA 031CE UT WOS:000236680900004 ER PT J AU Kobrick, M AF Kobrick, M TI On the toes of giants - How SRTM was born SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Kobrick, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM MKOBRICK@jpl.nasa.gov NR 0 TC 15 Z9 15 U1 0 U2 1 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 MAR PY 2006 VL 72 IS 3 BP 206 EP 210 PG 5 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 018GX UT WOS:000235753500001 ER PT J AU Gesch, DB Muller, JP Farr, TG AF Gesch, DB Muller, JP Farr, TG TI The shuttle radar topography mission - Data validation and applications SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Editorial Material C1 US Geol Survey, Ctr Earth Resources Observ & Sci, Sioux Falls, SD USA. UCL, Dept Geomat Engn, London, England. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Gesch, DB (reprint author), US Geol Survey, Ctr Earth Resources Observ & Sci, Sioux Falls, SD USA. OI Gesch, Dean/0000-0002-8992-4933; Farr, Thomas/0000-0001-5406-2096 NR 0 TC 16 Z9 17 U1 0 U2 5 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 MAR PY 2006 VL 72 IS 3 BP 233 EP 235 PG 3 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 018GX UT WOS:000235753500004 ER PT J AU Rodriguez, E Morris, CS Belz, JE AF Rodriguez, E Morris, CS Belz, JE TI A global assessment of the SRTM performance SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID SHUTTLE RADAR TOPOGRAPHY AB The NASA/NGA Shuttle Radar Topography Mission (SRTM) collected interferometric radar data which has been used by the Jet Propulsion Laboratory to generate a neor-global topography data product for latitudes smaller than 60 degrees. One of the primary goals of the mission was to produce a data set that was globally consistent and with quantified errors. To achieve this goal, an extensive global ground campaign was conducted by NGA and NASA to collect ground truth that would allow for the global validation of this unique data set. This paper documents the results of this SRTM validation effort using this global data set. The table shown below summarizes our results (all quantities represent 90 percent errors in meters). [GRAPHICS] In the paper, we present a detailed description of how the results in this table were obtained, We also present detailed characterizations of the height and planimetric components of the error, their magnitudes, geographical distribution, and spatial structure. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Rodriguez, E (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ernesto.rodriguez@jpl.nasa.gov NR 11 TC 301 Z9 323 U1 2 U2 25 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 MAR PY 2006 VL 72 IS 3 BP 249 EP 260 PG 12 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 018GX UT WOS:000235753500006 ER PT J AU Hofton, M Dubayah, R Blair, JB Rabine, D AF Hofton, M Dubayah, R Blair, JB Rabine, D TI Validation of SRTM elevations over vegetated and non-vegetated terrain using medium footprint lidar SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID RADAR TOPOGRAPHY MISSION; LASER ALTIMETER; BAND AB The Shuttle Radar Topography Mission (SRTM) generated one of the most-complete high-resolution digital topographic data sets of the world to date. The elevations generated by the on-board C-band sensor represent surface elevations in "bare earth" regions, and the elevations of various scatterers such as leaves and branches in other regions. Elevations generated by a medium-footprint (> 10 in diameter) laser altimeter (lidar) system known as NASA's Laser Vegetation Imaging Sensor (LVIS) were used to assess the accuracy of SRTM elevations at study sites of variable relief, and landcover. Five study sites in Maine, Massachusetts, Maryland, New Hampshire, and Costa Rica were chosen where coincident LVIS and SRTM data occur. Both ground and canopy top lidar elevations were compared to the SRTM elevations. In "bare earth" regions, the mean vertical offset between the sRTm elevations and LVIS ground elevations varied with study site and was approximately 0.0 m, 0.5 m, 3.0 m, 4.0 m, and 4.5 m at the Maine, Maryland, Massachusetts, New Hampshire, and Costa Rica study sites, respectively. In vegetated regions, the mean vertical offset increased, implying the phase center fell above the ground, and the offset varied by region. The sRTm elevations fell on average approximately 14 in below the LVIS canopy top elevations, except in Costa Rica where they were approximately 8 in below the canopy top. At all five study sites, SRTM elevations increased with increasing vertical extent (i.e., the difference between the LVIS canopy top and ground elevations and analogous to canopy height in vegetated regions). A linear relationship was found sufficient to describe the relationship between the SRTM-LVIS elevation difference and canopy vertical extent. C1 Univ Maryland, Dept Geog, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Laser Remote Sensing Lab, Greenbelt, MD 20771 USA. RP Hofton, M (reprint author), Univ Maryland, Dept Geog, College Pk, MD 20742 USA. EM mhofton@umd.edu RI Rabine, David/C-9626-2013; Blair, James/D-3881-2013; Beckley, Matthew/D-4547-2013 NR 18 TC 70 Z9 72 U1 1 U2 8 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 MAR PY 2006 VL 72 IS 3 BP 279 EP 285 PG 7 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 018GX UT WOS:000235753500009 ER PT J AU Carabajal, CC Harding, DJ AF Carabajal, CC Harding, DJ TI SRTM C-band and ICESat laser altimetry elevation comparisons as a function of tree cover and relief SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID BIAS AB The Geoscience Laser Altimeter System (GLAS) instrument onboard the Ice, Cloud, and land Elevation Satellite (ICESat) provides a globally distributed elevation data set that is well-suited to independently evaluate the accuracy of digital elevation models (DEMs), such as those produced by the Shuttle Radar Topography Mission (SRTM). We document elevation differences between SRTM C-band 1 and 3 arcsecond resolution DEMs and ICESat 1064 nm altimeter channel elevation data acquired in an areas of variable topography and vegetation cover in the South American Amazon Basin, Asian Tibetan Plateau - Himalayan Mountains, East Africa, western Australia, and the western United States. GLAS received waveforms enable the estimation of SRTM radar phase center elevation biases and variability with respect to the highest (canopy top where vegetated), centroid (distance-weighted average), and lowest (ground) elevations detected within ICESat laser footprints. Distributions of ICESat minus SRTM elevation differences are quantified as a function of waveform extent (a measure of within-footprint relief), SRTM roughness (standard deviation of a 3 X 3 array of elevation posts), and percent tree cover as reported in the Vegetation Continuous Field product derived from Moderate Resolution Imaging Spectrometer (MODIS) data. SRTM roughness is linearly correlated with waveform extent for areas where percent tree cover is low. The SRTM phase center elevation is usually located between the ICESat highest and lowest elevations, and on average is closely correlated with the ICESat centroid. In areas of low relief and sparse tree cover, the mean of ICESat centroid minus SRTM phase center elevation differences for the five regions examined vary between -3.9 and 1.0 m, and the corresponding standard deviations are between 3.0 and 3.7-m. With increasing SRTM roughness and/or tree cover, the SRTM elevation remains essentially unbiased with respect to the ICESat centroid but the standard deviations of the differences increase to between 20 and 34 m, depending on the region. For the Australia, Amazon, Africa, United States, and Asia regions, including all tree cover and roughness conditions, 90 percent of the SRTM elevations are within 6.9, 11.5, 12.1, 16.8, and 37.1 m of the ICESat centroid, respectively. In vegetated areas, the SRTM elevation on average is located approximately 40 percent of the distance from the canopy top to the ground. The variability of this result increases significantly with increasing SRTM roughness. The results are generally consistent for the five regions examined, providing a method to estimate for any location the correspondence between SRTM elevations and highest, average, and lowest elevations using the globally-available MODIS-derived estimate of tree cover and the measure of SRTM roughness. C1 NASA, Goddard Space Flight Ctr, NVI Inc, Space Geodesy Lab, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Planetary Geodynam Lab, Greenbelt, MD 20771 USA. RP Carabajal, CC (reprint author), NASA, Goddard Space Flight Ctr, NVI Inc, Space Geodesy Lab, Code 661, Greenbelt, MD 20771 USA. EM Claudia@bowie.gsfc.nasa.gov RI Harding, David/F-5913-2012 NR 16 TC 88 Z9 92 U1 3 U2 15 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 MAR PY 2006 VL 72 IS 3 BP 287 EP 298 PG 12 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 018GX UT WOS:000235753500010 ER PT J AU Simard, M Zhang, KQ Rivera-Monroy, VH Ross, MS Ruiz, PL Castaneda-Moya, E Twilley, RR Rodriguez, E AF Simard, M Zhang, KQ Rivera-Monroy, VH Ross, MS Ruiz, PL Castaneda-Moya, E Twilley, RR Rodriguez, E TI Mapping height and biomass of mangrove forests in Everglades National Park with SRTM elevation data SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID SYNTHETIC-APERTURE RADAR; ORGANIC-MATTER; ECOSYSTEMS; BACKSCATTER; PATTERNS; WETLANDS; ESTUARY; IKONOS; IMAGES; COAST AB We produced a landscape scale map of mean tree height in mangrove forests in Everglades National Park (ENP) using the elevation data from the Shuttle Radar Topography Mission (SRTM). The SRTM data was calibrated using airborne lidar data and a high resolution USGs digital elevation model (DEM). The resulting mangrove height map has a mean tree height error of 2.0 m (RMSE) over a pixel of 30 m. In addition, we used field data to derive a relationship between mean forest stand height and biomass in order to map the spatial distribution of standing biomass of mangroves for the entire National Park. The estimation showed that most of the mangrove standing biomass in the ENP resides in intermediate-height mangrove stands around 8 m. We estimated the total mangrove standing biomass in ENP to be 5.6 x 10(9) kg. C1 CALTECH, Jet Prop Lab, Radar & Engn Sect, Pasadena, CA 91109 USA. Florida Int Univ, Int Hurricane Res Ctr, Miami, FL 33199 USA. Florida Int Univ, Dept Environm Sci, Miami, FL 33199 USA. Louisiana State Univ, Dept Oceanog & Coastal Sci, Wetland Biogeochem Inst, Baton Rouge, LA 70803 USA. Florida Int Univ, SE Environm Res Ctr, Miami, FL 33199 USA. RP Simard, M (reprint author), CALTECH, Jet Prop Lab, Radar & Engn Sect, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM marc.simard@jpl.nasa.gov RI Rivera-Monroy, Victor/G-7329-2011; Simard, Marc/H-3516-2013 OI Simard, Marc/0000-0002-9442-4562 NR 49 TC 110 Z9 118 U1 9 U2 39 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 MAR PY 2006 VL 72 IS 3 BP 299 EP 311 PG 13 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 018GX UT WOS:000235753500011 ER PT J AU Aguilar, A Gillaspy, JD Gribakin, GF Phaneuf, RA Gharaibeh, MF Kozlov, MG Bozek, JD Kilcoyne, ALD AF Aguilar, A Gillaspy, JD Gribakin, GF Phaneuf, RA Gharaibeh, MF Kozlov, MG Bozek, JD Kilcoyne, ALD TI Absolute photoionization cross sections for Xe4+, Xe5+, and Xe6+ near 13.5 nm: Experiment and theory SO PHYSICAL REVIEW A LA English DT Article ID EXTREME-ULTRAVIOLET; RADIATION TRANSPORT; CHARGED IONS; 4D THRESHOLD; BA+ IONS; XE+ IONS; XENON; LITHOGRAPHY; PLASMA; EUV AB Absolute photoionization cross-section measurements for a mixture of ground and metastable states of Xe4+, Xe5+, and Xe6+ are reported in the photon energy range of 4d -> nf transitions, which occur within or adjacent to the 13.5 nm window for extreme ultraviolet lithography light source development. The reported values allow the quantification of opacity effects in xenon plasmas due to these 4d -> nf autoionizing states. The oscillator strengths for the 4d -> 4f and 4d -> 5f transitions in Xeq+ (q=1-6) ions are calculated using nonrelativistic Hartree-Fock and random phase approximations. These are compared with published experimental values for Xe+ to Xe3+ and with the values obtained from the present experimental cross-section measurements for Xe4+ to Xe6+. The calculations assisted in the determination of the metastable content in the ion beams for Xe5+ and Xe6+. The experiments were performed by merging a synchrotron photon beam generated by an undulator beamline of the Advanced Light Source with an ion beam produced by an electron cyclotron resonance ion source. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. Univ Nevada, Dept Phys, Reno, NV 89557 USA. Petersburg Nucl Phys Inst, Gatchina 188300, Russia. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Aguilar, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM alex.aguilar@jpl.nasa.gov; john.gillaspy@nist.gov; g.gribakin@am.qub.ac.uk; phaneuf@physics.unr.edu RI Bozek, John/E-4689-2010; Kozlov, Mikhail/D-8963-2011; Bozek, John/E-9260-2010; Kilcoyne, David/I-1465-2013 OI Kozlov, Mikhail/0000-0002-7751-6553; Bozek, John/0000-0001-7486-7238; NR 40 TC 19 Z9 19 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 MAR PY 2006 VL 73 IS 3 AR 032717 DI 10.1103/PhysRevA.73.032717 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 028DQ UT WOS:000236467500103 ER PT J AU Bilodeau, RC Bozek, JD Ackerman, GD Aguilar, A Berrah, N AF Bilodeau, RC Bozek, JD Ackerman, GD Aguilar, A Berrah, N TI Photodetachment of He- near the 1s threshold: Absolute cross-section measurements and postcollision interactions SO PHYSICAL REVIEW A LA English DT Article ID INNER-SHELL PHOTODETACHMENT; PHOTOIONIZATION; REGION; STATE; RESONANCES; HELIUM; ENERGY; ION AB Inner-shell photodetachment of He- is studied near the He- 1s2s2p P-4(o)-> He 2s2p P-3(o) threshold. The spectrum over this region shows significant suppression of He+ signal production due to postcollision interaction (PCI) effects. The observed shape and absolute cross section are in general agreement with theoretical predictions when corrections for semiclassical PCI effects are included. C1 Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Nevada, Dept Phys, Reno, NV 89557 USA. RP CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RI Bozek, John/E-4689-2010; Bozek, John/E-9260-2010; OI Bozek, John/0000-0001-7486-7238; Bilodeau, Rene/0000-0001-8607-2328 NR 27 TC 8 Z9 8 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 2006 VL 73 IS 3 AR 034701 DI 10.1103/PhysRevA.73.034701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 028DQ UT WOS:000236467500195 ER PT J AU Wang, SY Johnson, PV Malone, CP Kanik, I Khakoo, MA AF Wang, SY Johnson, PV Malone, CP Kanik, I Khakoo, MA TI Transmission effects in unfolding electronic-vibrational electron-molecule energy-loss spectra SO PHYSICAL REVIEW A LA English DT Article ID DIFFERENTIAL CROSS-SECTIONS; IMPACT EXCITATION; STATES; N-2; XE AB The results of an investigation concerning the sensitivity of conventional unfolding methods applied to electronic-vibrational electron-energy-loss spectra to the transmission efficiency of electron spectrometers are presented. This investigation was made in an effort to understand differences in the differential cross sections for excitation of low-lying electronic states determined experimentally by various groups using electronic-vibrational energy-loss spectra of N-2. In these experiments, very similar spectral unfolding methods were used, which relied on similar Franck-Condon factors. However, the overall analyses of the electron scattering spectra (by the individual groups) resulted in large differences among the differential cross sections determined from these energy-loss spectra. The transmission response of the experimental apparatus to different-energy scattered electrons has often been discussed as a key factor that caused these disagreements. The present investigation shows in contrast that the effect of transmission is smaller than that required to independently explain such differences, implying that other systematic effects are responsible for the existing differences between measurements. C1 Calif State Univ Fullerton, Dept Phys, Fullerton, CA 92831 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Wang, SY (reprint author), Calif State Univ Fullerton, Dept Phys, Fullerton, CA 92831 USA. RI Malone, Charles/A-6294-2010; Wang, Shiyang/C-1729-2012; Johnson, Paul/D-4001-2009 OI Malone, Charles/0000-0001-8418-1539; Johnson, Paul/0000-0002-0186-8456 NR 18 TC 3 Z9 3 U1 0 U2 1 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 MAR PY 2006 VL 73 IS 3 AR 034702 DI 10.1103/PhysRevA.73.034702 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 028DQ UT WOS:000236467500196 ER PT J AU Malkova, N Ning, CZ AF Malkova, N Ning, CZ TI Shockley and Tamm surface states in photonic crystals SO PHYSICAL REVIEW B LA English DT Article ID WAVES; MEDIA; ARRAYS AB Existence of the Shockley surface states in photonic crystals is demonstrated for the first time. We show that in photonic crystals, the surface states of defect chain with unit cell containing one defect are the Tamm rather than Shockley states as commonly assumed. The Shockley states can appear only in the defect chain with unit cell containing more than one defect. We first analyze the surface states using the tight-binding theory. Theoretical predictions are confirmed by the numerical simulations. 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 18 TC 38 Z9 38 U1 2 U2 15 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 MAR PY 2006 VL 73 IS 11 AR 113113 DI 10.1103/PhysRevB.73.113113 PG 4 WC Physics, Condensed Matter SC Physics GA 028DO UT WOS:000236467300013 ER PT J AU Strekalov, VN Strekalov, DV AF Strekalov, VN Strekalov, DV TI Initial stages of equilibrium thermographitization of diamond SO PHYSICAL REVIEW B LA English DT Article ID LASER-INDUCED DAMAGE; THERMAL-DESORPTION; HIGH-PRESSURE; GRAPHITIZATION; GRAPHITE; SURFACE; TRANSFORMATION; TRANSITIONS; CARBON; PHASE AB A consistent quantum-statistical theory of equilibrium graphitization of diamond is suggested based on the truncated harmonic oscillator model. The graphitization is caused by the interaction of carbon atoms with phonons, while the essential role is played by spontaneous emission of acoustic phonons. The model allows us to carry out the analytical description of the process in a general form all the way to estimations of the observable numerical values. The values found are compatible with the computer simulation results obtained independently by several researchers. It turns out that the initial state of carbon sp(3) (diamond) is highly unstable and can, at high temperatures, spontaneously convert to sp(2) (graphite) on a time scale of 10(-14) s. This transition is the base for graphitization. After the process has started, it slows down because of saturation effects. The temperature dependence of graphitization rates has been established. The developed theory of equilibrium graphitization can be considered as a starting point for consistent study of the later stages of graphitization, when the saturation is taken into account; as well as for the study of nonequilibrium graphitization in laser or electron beams. C1 Moscow State Univ Technol STANKIN, Dept Phys, Moscow 101472, Russia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Strekalov, VN (reprint author), Moscow State Univ Technol STANKIN, Dept Phys, 3A Vadkovsky Per, Moscow 101472, Russia. EM stvn@stankin.ru; dmitry.v.strekalov@jpl.nasa.gov NR 29 TC 0 Z9 0 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR PY 2006 VL 73 IS 11 AR 115417 DI 10.1103/PhysRevB.73.115417 PG 9 WC Physics, Condensed Matter SC Physics GA 028DO UT WOS:000236467300137 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 Kawamura, S 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 Miyoki, S 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 Rudiger, 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 Takamori, A Tanner, DB Tarallo, M Tariq, H 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 AF 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 Kawamura, S 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 Miyoki, S 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 Rudiger, 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 Takamori, A Tanner, DB Tarallo, M Tariq, H 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 TI Search for gravitational waves from binary black hole inspirals in LIGO data SO PHYSICAL REVIEW D LA English DT Article ID COMPACT BINARIES; FILTERS; RATES AB We report on a search for gravitational waves from binary black hole inspirals in the data from the second science run of the LIGO interferometers. The search focused on binary systems with component masses between 3 and 20M. Optimally oriented binaries with distances up to 1 Mpc could be detected with efficiency of at least 90%. We found no events that could be identified as gravitational waves in the 385.6 hours of data that we searched. C1 CALTECH, LIGO, Pasadena, CA 91125 USA. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-30167 Hannover, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Cardiff Univ, Cardiff CF2 3YB, Wales. Carleton Coll, Northfield, MN 55057 USA. Columbia Univ, New York, NY 10027 USA. Embry Riddle Aeronaut Univ, Prescott, AZ 86301 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Interuniv Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. MIT, LIGO, Cambridge, MA 02139 USA. LIGO Hanford Observ, Richland, WA 99352 USA. LIGO Livingston Observ, Livingston, LA 70754 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Loyola Univ, New Orleans, LA 70118 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ Japan, Tokyo 1818588, Japan. Northwestern Univ, Evanston, IL 60208 USA. Salish Kootenai Coll, Pablo, MT 59855 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Stanford Univ, Stanford, CA 94305 USA. Syracuse Univ, Syracuse, NY 13244 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Texas, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. Trinity Univ, San Antonio, TX 78212 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. Univ Illes Balears, E-07122 Palma de Mallorca, Spain. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Maryland, College Pk, MD 20742 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Vassar Coll, Poughkeepsie, NY 12604 USA. Washington State Univ, Pullman, WA 99164 USA. RP Abbott, B (reprint author), CALTECH, LIGO, Pasadena, CA 91125 USA. RI Sylvestre, Julien/A-8610-2009; Beausoleil, Raymond/C-5076-2009; Finn, Lee Samuel/A-3452-2009; McClelland, David/E-6765-2010; Hild, Stefan/A-3864-2010; Casey, Morag/C-9703-2010; Rowan, Sheila/E-3032-2010; Strain, Kenneth/D-5236-2011; Raab, Frederick/E-2222-2011; Freise, Andreas/F-8892-2011; Kawabe, Keita/G-9840-2011; Tarallo, Marco/B-2096-2012; 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; Ward, Robert/I-8032-2014; Agresti, Juri/G-8168-2012; 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; Schutz, Bernard/B-1504-2010; Liu, Sheng/K-2815-2013; Vyatchanin, Sergey/J-2238-2012; van Putten, Maurice/F-5237-2011 OI Sylvestre, Julien/0000-0001-8136-4348; Finn, Lee Samuel/0000-0002-3937-0688; McClelland, David/0000-0001-6210-5842; Strain, Kenneth/0000-0002-2066-5355; Tarallo, Marco/0000-0001-5169-4987; Zweizig, John/0000-0002-1521-3397; Fairhurst, Stephen/0000-0001-8480-1961; Taylor, Ian/0000-0001-5040-0772; 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; Papa, M.Alessandra/0000-0002-1007-5298; Vecchio, Alberto/0000-0002-6254-1617; Ottewill, Adrian/0000-0003-3293-8450; Sigg, Daniel/0000-0003-4606-6526; Frey, Raymond/0000-0003-0341-2636; Ward, Robert/0000-0001-5503-5241; Whelan, John/0000-0001-5710-6576; Stuver, Amber/0000-0003-0324-5735; Agresti, Juri/0000-0001-6119-2470; Allen, Bruce/0000-0003-4285-6256; Pitkin, Matthew/0000-0003-4548-526X; NR 35 TC 65 Z9 65 U1 1 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD MAR PY 2006 VL 73 IS 6 AR 062001 DI 10.1103/PhysRevD.73.062001 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 028DD UT WOS:000236466100004 ER PT J AU Harstad, K Bellan, J AF Harstad, K Bellan, J TI On possible release of micro be-containing particulates from a Mars lander spacecraft SO PLANETARY AND SPACE SCIENCE LA English DT Article DE Mars planetary protection; adhesion; hamaker constant; microbes; saltation ID GLOBAL DUST STORMS; MARTIAN ATMOSPHERE; PARTICLE ADHESION; BACILLUS-SUBTILIS; TURBULENT FLOWS; MODEL; SIZE; SIMULATIONS; RESTITUTION; THRESHOLD AB Due to possible planet contamination, before Earth-departure, Mars landers and/or rovers are subject to strict requirements on the maximum number of attached spores or particles that carry viable microbes. Estimates of the release rates of these particles on Mars are made considering the three mechanisms of wind shear, collision with suspended dust, and collision with saltating sand particles. The first mechanism is found to apply only to particles of size greater than 10 pm, the second mechanism has a characteristic particle adhesion half life that is so long as to be of no concern, and the third mechanism is deemed of possible importance, vitally depending on attached particle size and detailed surface characteristics of sand and spacecraft. While not investigated in detail, dust devils are shown to be possible contributors to release of microbe-containing particles. (c) 2006 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bellan, J (reprint author), CALTECH, Jet Prop Lab, M-S 125-109,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Josette.Bellan@jpl.nasa.gov NR 49 TC 2 Z9 2 U1 0 U2 6 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 MAR PY 2006 VL 54 IS 3 BP 273 EP 286 DI 10.1016/j.pss.2005.12.007 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019DD UT WOS:000235814900004 ER PT J AU Ruthruff, E Van Selst, M Johnston, JC Remington, R AF Ruthruff, E Van Selst, M Johnston, JC Remington, R TI How does practice reduce dual-task interference: Integration, automatization, or just stage-shortening? SO PSYCHOLOGICAL RESEARCH-PSYCHOLOGISCHE FORSCHUNG LA English DT Article ID PSYCHOLOGICAL REFRACTORY-PERIOD; RESPONSE SELECTION; 2 THINGS; IDEOMOTOR COMPATIBILITY; CENTRAL POSTPONEMENT; PERFORMANCE; BOTTLENECK; ATTENTION; ELIMINATION; LOCUS AB The present study assessed three hypotheses of how practice reduces dual-task interference: Practice teaches participants to efficiently integrate performance of a task pair; practice promotes automatization of individual tasks, allowing the central bottleneck to be bypassed; practice leaves the bottleneck intact but shorter in duration. These hypotheses were tested in two transfer-of-training experiments. Participants received one of three training types (Task 1 only, or Task 2 only, or dual-task), followed by dual-task test sessions. Practice effects in Experiment 1 (Task 1: auditory-vocal; Task 2: visual-manual) were fully explained by the intact bottleneck hypothesis, without task integration or automatization. This hypothesis also accounted well for the majority of participants when the task order was reversed (Experiment 2). In this case, however, there were multiple indicators that several participants had succeeded in eliminating the bottleneck by automatizing one or both tasks. Neither experiment provided any evidence that practice promotes efficient task integration. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. San Jose State Univ, Dept Psychol, San Jose, CA 95192 USA. RP Ruthruff, E (reprint author), NASA, Ames Res Ctr, MS 262-4, Moffett Field, CA 94035 USA. EM eruthruff@mail.arc.nasa.gov NR 53 TC 77 Z9 77 U1 1 U2 9 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0340-0727 J9 PSYCHOL RES-PSYCH FO JI Psychol. Res.-Psychol. Forsch. PD MAR PY 2006 VL 70 IS 2 BP 125 EP 142 DI 10.1007/s00426-004-0192-7 PG 18 WC Psychology, Experimental SC Psychology GA 034XZ UT WOS:000236965500005 PM 16703392 ER PT J AU Dolan, JF Etzel, PB Boyd, PT AF Dolan, JF Etzel, PB Boyd, PT TI Measuring the mass of 4U 0900-40 dynamically SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID X-RAY BINARIES; VELA X-1; NEUTRON-STAR; SCORPIUS X-1; BLACK-HOLES; PULSARS; HD-77581; 4U-1700-37; SYSTEMS; PHYSICS AB Accurate measurements of neutron star masses are needed to constrain the equation of state of neutron star matter - of importance to both particle physics and the astrophysics of neutron stars - and to identify the evolutionary track of the progenitor stars that form neutron stars. The best measured values of the mass of 4U 0900 - 40 (=Vela XR-1), 1.86 +/- 0.16 M-circle dot (Barziv et al.) and 1.93 +/- 0.20 M-circle dot (Abubekerov et al.), make it a leading candidate for the most massive neutron star known. The direct relationship between the maximum mass of neutron stars and the equation of state of ultradense matter makes 4U 0900-40 an important neutron star mass to determine accurately. The confidence intervals on previous mass estimates obtained from observations that include parameters determined by nondynamical methods are not small enough to significantly restrict possible equations of state. We describe here a purely dynamical method for determining the mass of 4U 0900-40, an X-ray pulsar, using the reprocessed UV pulses emitted by its B0.5 Ib companion. One can derive the instantaneous radial velocity of each component through simultaneous X-ray and UV observations at the two quadratures of the system. The Doppler shift caused by the primary's rotational velocity and the illumination pattern of the X-rays on the primary, two of the three principal contributors to the uncertainty on the derived mass of the neutron star, almost exactly cancel out by symmetry in this method. A heuristic measurement of the mass of 4U 0900-40, using observations obtained previously with the High Speed Photometer on the Hubble Space Telescope, is given in an appendix. C1 NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. San Diego State Univ, Dept Astron, San Diego, CA 92182 USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. RP Dolan, JF (reprint author), NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. EM Joseph.F.Dolan@nasa.gov; etzel@algol.sdsu.edu; padi@milkyway.gsfc.nasa.gov RI Boyd, Patricia/D-3274-2012 NR 35 TC 0 Z9 0 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 MAR PY 2006 VL 118 IS 841 BP 392 EP 398 DI 10.1086/499500 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 029RQ UT WOS:000236582500005 ER PT J AU Anantram, MP Leonard, F AF Anantram, MP Leonard, F TI Physics of carbon nanotube electronic devices SO REPORTS ON PROGRESS IN PHYSICS LA English DT Review ID CURRENT-CARRYING CAPACITY; FIELD-EFFECT TRANSISTORS; CURRENT SATURATION; QUANTUM CONDUCTANCE; WORK-FUNCTIONS; SINGLE; EMISSION; RESISTANCE; TRANSPORT; STATES AB Carbon nanotubes (CNTs) are amongst the most explored one-dimensional nanostructures and have attracted tremendous interest from fundamental science and technological perspectives. Albeit topologically simple, they exhibit a rich variety of intriguing electronic properties, such as metallic and semiconducting behaviour. Furthermore, these structures are atomically precise, meaning that each carbon atom is still three-fold coordinated without any dangling bonds. CNTs have been used in many laboratories to build prototype nanodevices. These devices include metallic wires, field-effect transistors, electromechanical sensors and displays. They potentially form the basis of future all-carbon electronics. This review deals with the building blocks of understanding the device physics of CNT-based nanodevices. There are many features that make CNTs different from traditional materials, including chirality-dependent electronic properties, the one-dimensional nature of electrostatic screening and the presence of several direct bandgaps. Understanding these novel properties and their impact on devices is crucial in the development and evolution of CNT applications. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. Sandia Natl Labs, Nanoscale Sci & Technol Dept, Livermore, CA 94551 USA. RP NASA, Ames Res Ctr, Ctr Nanotechnol, Mail Stop 229-1, Moffett Field, CA 94035 USA. EM anant@arc.nasa.gov; fleonar@sandia.gov RI 李, 府中/H-4357-2011 NR 121 TC 312 Z9 317 U1 16 U2 129 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0034-4885 EI 1361-6633 J9 REP PROG PHYS JI Rep. Prog. Phys. PD MAR PY 2006 VL 69 IS 3 BP 507 EP 561 DI 10.1088/0034-4885/69/3/R01 PG 55 WC Physics, Multidisciplinary SC Physics GA 031IJ UT WOS:000236697700001 ER PT J AU Enjolras, V Vincent, P Souyris, JC Rodriguez, E Phalippou, L Cazenave, A AF Enjolras, Vivien Vincent, Patrick Souyris, Jean-Claude Rodriguez, Ernesto Phalippou, Laurent Cazenave, Anny TI Performances study of interferometric radar altimeters: from the instrument to the global mission definition SO SENSORS LA English DT Article DE altimetry; interferometry; error budget; system analysis; ocean; mesoscale ID SAR IMAGERY; STATISTICS; TOPEX/POSEIDON; BACKSCATTER AB The main limitations of standard nadir-looking radar altimeters have been known for long. They include the lack of coverage (intertrack distance of typically 150 km for the T/P / Jason tandem), and the spatial resolution ( typically 2 km for T/P and Jason), expected to be a limiting factor for the determination of mesoscale phenomena in deep ocean. In this context, various solutions using off-nadir radar interferometry have been proposed by Rodriguez and al to give an answer to oceanographic mission objectives. This paper addresses the performances study of this new generation of instruments, and dedicated mission. A first approach is based on the Wide-Swath Ocean Altimeter (WSOA) intended to be implemented onboard Jason-2 in 2004 but now abandoned. Every error domain has been checked: the physics of the measurement, its geometry, the impact of the platform and external errors like the tropospheric and ionospheric delays. We have especially shown the strong need to move to a sun-synchronous orbit and the non-negligible impact of propagation media errors in the swath, reaching a few centimetres in the worst case. Some changes in the parameters of the instrument have also been discussed to improve the overall error budget. The outcomes have led to the definition and the optimization of such an instrument and its dedicated mission. C1 Ctr Natl Etud Spatiales, F-31055 Toulouse 4, France. LEGOS, F-31400 Toulouse, France. IFREMER, F-92138 Issy Les Moulineaux, France. JPL, Pasadena, CA 91109 USA. ALCATEL SPACE, F-31000 Toulouse, France. RP Enjolras, V (reprint author), Ctr Natl Etud Spatiales, 18 Ave Edouard Belin, F-31055 Toulouse 4, France. EM vivien.enjolras@gmail.com; patrick.vincent@ifremer.fr; Ernesto.rodriguez@jpl.nasa.gov; Laurent.Phalippou@alcatelaleniaspace.com; anny.cazenave@cnes.fr NR 35 TC 15 Z9 18 U1 0 U2 4 PU MDPI AG PI BASEL PA POSTFACH, CH-4005 BASEL, SWITZERLAND SN 1424-8220 J9 SENSORS-BASEL JI Sensors PD MAR PY 2006 VL 6 IS 3 BP 164 EP 192 DI 10.3390/s6030164 PG 29 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 043NY UT WOS:000237609200004 ER PT J AU Im, Y Lee, C Vasquez, RP Bangar, MA Myung, NV Menke, EJ Penner, RM Yun, MH AF Im, Y Lee, C Vasquez, RP Bangar, MA Myung, NV Menke, EJ Penner, RM Yun, MH TI Investigation of a single Pd nanowire for use as a hydrogen sensor SO SMALL LA English DT Article DE hydrogen; lithography; nanowires; palladium; sensors ID ELECTRICAL-RESISTIVITY; ARRAYS C1 Univ Pittsburgh, Dept Elect & Comp Engn, Pittsburgh, PA 15261 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Riverside, Dept Chem & Environm Engn, Riverside, CA 90025 USA. Univ Calif Riverside, Ctr Nanoscale Sci & Engn, Riverside, CA 90025 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. RP Univ Pittsburgh, Dept Elect & Comp Engn, Pittsburgh, PA 15261 USA. EM yunmh@engr.pitt.edu RI Penner, Reginald/D-1521-2009; Menke, Erik/D-4305-2009 OI Penner, Reginald/0000-0003-2831-3028; NR 18 TC 117 Z9 118 U1 8 U2 53 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 1613-6810 EI 1613-6829 J9 SMALL JI Small PD MAR PY 2006 VL 2 IS 3 BP 356 EP 358 DI 10.1002/smll.200500365 PG 3 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 011EA UT WOS:000235249600010 PM 17193049 ER PT J AU Sylwester, B Kepa, A Kordylewski, Z Phillips, KJH Kuznetsov, VD AF Sylwester, B Kepa, A Kordylewski, Z Phillips, KJH Kuznetsov, VD TI Thermodynamics of selected solar flares as determined from the analysis of the spectra obtained with the RESIK instrument SO SOLAR SYSTEM RESEARCH LA English DT Article ID TEMPERATURE DIAGRAM; FLARING LOOPS; RAY; SPECTROMETER; EVOLUTION; EMISSION; DYNAMICS AB The RESIK instrument is an X-ray spectrometer with bent crystals onboard the CORONAS-F satellite. It was used to observe the spectra of solar flares, active regions, and quiet corona. During the period of the instrument's operation, many spectra were collected in four energy channels covering the wavelength range from 3.2 to 6.1 angstrom. For the present analysis, we selected solar flares of various X-ray classes (13, C, and M in the GOES notation), which were observed during moderate level of solar activity (from January to March 2003). The analysis of the RESIK spectra fultilled with different techniques allowed us to determine the temperature, emission measure, and temperature distribution of the differential emission measure, as well as to examine their time variability. C1 Polish Acad Sci, Space Res Ctr, PL-51622 Wroclaw, Poland. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Russian Acad Sci, Pushkov Inst Terr Magnet Ionosphere & Radio Wave, Troitsk 142090, Moscow Oblast, Russia. RP Sylwester, B (reprint author), Polish Acad Sci, Space Res Ctr, Kopernika 11, PL-51622 Wroclaw, Poland. NR 7 TC 3 Z9 3 U1 0 U2 3 PU MAIK NAUKA/INTERPERIODICA/SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 0038-0946 J9 SOLAR SYST RES+ JI Solar Syst. Res. PD MAR-APR PY 2006 VL 40 IS 2 BP 125 EP 132 DI 10.1134/S0038094606020067 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 040GL UT WOS:000237366900006 ER PT J AU Alexander, D Richardson, IG Zurbuchen, TH AF Alexander, David Richardson, Ian G. Zurbuchen, Thomas H. TI A brief history of CME science SO SPACE SCIENCE REVIEWS LA English DT Article DE CMEs; corona; history ID CORONAL MASS EJECTIONS; SOLAR COSMIC RAYS; MAGNETIC STORMS; INTERPLANETARY SHOCKS; FLARE; FIELD; PARTICLES; SPEEDS; MODEL; SUN AB We present here a brief summary of the rich heritage of observational and theoretical research leading to the development of our current understanding of the initiation, structure, and evolution of Coronal Mass Ejections. C1 Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. NASA GSFC, Astroparticle Phys Lab, Greenbelt, MD 20771 USA. Univ Michigan, Dept AOSS, Ann Arbor, MI 48109 USA. RP Alexander, D (reprint author), Rice Univ, Dept Phys & Astron, 6100 Main St, Houston, TX 77005 USA. EM dalex@rice.edu OI Richardson, Ian/0000-0002-3855-3634 NR 51 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 3 EP 11 DI 10.1007/s11214-006-9008-y PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400002 ER PT J AU Zurbuchen, TH Richardson, IG AF Zurbuchen, Thomas H. Richardson, Ian G. TI In-situ solar wind and magnetic field signatures of interplanetary coronal mass ejections SO SPACE SCIENCE REVIEWS LA English DT Article DE interplanetary coronal mass ejections; solar wind plasma; interplanetary magnetic field ID INTER-PLANETARY SHOCK; GEOMAGNETIC STORMS; ELECTRON-TEMPERATURE; MHD SIMULATION; HEAVY-IONS; CLOUDS; PLASMA; HELIUM; EVENTS; FLARE AB The heliospheric counterparts of coronal mass ejections (CMEs) at the Sun, interplanetary coronal mass ejections (ICMEs), can be identified in situ based on a number of magnetic field, plasma, compositional and energetic particle signatures as well as combinations thereof. We summarize these signatures and their implications for understanding the nature of these structures and the physical properties of coronal mass ejections. We conclude that our understanding of ICMEs is far from complete and formulate several challenges that, if addressed, would substantially improve our knowledge of the relationship between CMEs at the Sun and in the heliosphere. C1 Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. NASA Goddard Space Flight Ctr, Astroparticle Phys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Zurbuchen, TH (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. EM thomasz@umich.edu OI Richardson, Ian/0000-0002-3855-3634 NR 82 TC 178 Z9 185 U1 0 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 31 EP 43 DI 10.1007/s11214-006-9010-4 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400004 ER PT J AU Schwenn, R Raymond, JC Alexander, D Ciaravella, A Gopalswamy, N Howard, R Hudson, H Kaufmann, P Klassen, A Maia, D Munoz-Martinez, G Pick, M Reiner, M Srivastava, N Tripathi, D Vourlidas, A Wang, YM Zhang, J AF Schwenn, R. Raymond, J. C. Alexander, D. Ciaravella, A. Gopalswamy, N. Howard, R. Hudson, H. Kaufmann, P. Klassen, A. Maia, D. Munoz-Martinez, G. Pick, M. Reiner, M. Srivastava, N. Tripathi, D. Vourlidas, A. Wang, Y. -M. Zhang, J. TI Coronal observations of CMEs SO SPACE SCIENCE REVIEWS LA English DT Article DE solar corona; eruptive prominences; coronal mass ejections (CMEs); flares; solar wind; solarmagnetic field; magnetic reconnection; interplanetary shock waves; ICMEs; space weather; solar energetic particles (SEPs); radio bursts ID SELF-SIMILAR MAGNETOHYDRODYNAMICS; EJECTION-ASSOCIATED SHOCK; DURATION SOLAR-FLARE; WHITE-LIGHT IMAGES; WHOLE SUN MONTH; X-RAY SOURCES; MASS EJECTIONS; MAGNETIC RECONNECTION; ERUPTIVE PROMINENCE; ACTIVE-REGION AB CMEs have been observed for over 30 years with a wide variety of instruments. It is now possible to derive detailed and quantitative information on CME morphology, velocity, acceleration and mass. Flares associated with CMEs are observed in X-rays, and several different radio signatures are also seen. Optical and UV spectra of CMEs both on the disk and at the limb provide velocities along the line of sight and diagnostics for temperature, density and composition. From the vast quantity of data we attempt to synthesize the current state of knowledge of the properties of CMEs, along with some specific observed characteristics that illuminate the physical processes occurring during CME eruption. These include the common three-part structures of CMEs, which is generally attributed to compressed material at the leading edge, a low-density magnetic bubble and dense prominence gas. Signatures of shock waves are seen, but the location of these shocks relative to the other structures and the occurrence rate at the heights where Solar Energetic Particles are produced remains controversial. The relationships among CMEs, Moreton waves, EIT waves, and EUV dimming are also cloudy. The close connection between CMEs and flares suggests that magnetic reconnection plays an important role in CME eruption and evolution. We discuss the evidence for reconnection in current sheets from white-light, X-ray, radio and UV observations. Finally, we summarize the requirements for future instrumentation that might answer the outstanding questions and the opportunities that new space-based and ground-based observatories will provide in the future. C1 Max Planck Inst Sonnensystemforsch, Katlenburg Duhm, Germany. Ctr Astrophys, Cambridge, MA USA. Rice Univ, Dept Phys & Astron, Houston, TX 77251 USA. INAF, Osservat Astron Palermo, Palermo, Italy. George Mason Univ, Sch Computat Sci, Fairfax, VA USA. NASA GSFC, Lab Extraterr Phys, Greenbelt, MD USA. US Naval Res Lab, Washington, DC USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA USA. Univ Presbiteriana Mackenzie, CRAAM, Sao Paulo, SP, Brazil. Univ Estadual Campinas, CCS, Campinas, SP, Brazil. Astrophys Inst Potsdam, Potsdam, Germany. Univ Porto, Fac Ciencias, CICGE, Observ Astron Prof Manuel Barros, Vila Nova De Gaia, Portugal. Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City, DF, Mexico. CNRS, LESIA, UMR 8109, Observ Paris, Meudon, France. Udaipur Solar Observ, Phys Res Lab, Udaipur, India. RP Schwenn, R (reprint author), Max Planck Inst Sonnensystemforsch, Katlenburg Duhm, Germany. EM schwenn@linmpi.mpg.de RI Vourlidas, Angelos/C-8231-2009; Gopalswamy, Nat/D-3659-2012; Tripathi, Durgesh/D-9390-2012 OI Vourlidas, Angelos/0000-0002-8164-5948; Tripathi, Durgesh/0000-0003-1689-6254 NR 223 TC 51 Z9 53 U1 0 U2 6 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 127 EP 176 DI 10.1007/s11214-006-9016-y PG 50 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400010 ER PT J AU Wimmer-Schweingruber, RF Crooker, NU Balogh, A Bothmer, V Forsyth, RJ Gazis, P Gosling, JT Horbury, T Kilchenmann, A Richardson, IG Richardson, JD Riley, P Rodriguez, L Von Steiger, R Wurz, P Zurbuchen, TH AF Wimmer-Schweingruber, R. F. Crooker, N. U. Balogh, A. Bothmer, V. Forsyth, R. J. Gazis, P. Gosling, J. T. Horbury, T. Kilchenmann, A. Richardson, I. G. Richardson, J. D. Riley, P. Rodriguez, L. Von Steiger, R. Wurz, P. Zurbuchen, T. H. TI Understanding interplanetary coronal mass ejection signatures SO SPACE SCIENCE REVIEWS LA English DT Article DE coronal mass ejections; interplanetary physics; solar wind ID INTER-PLANETARY SHOCK; SOLAR ENERGETIC PARTICLES; MAGNETIC-FIELD STRUCTURE; COROTATING INTERACTION REGIONS; HELIOSPHERIC CURRENT SHEET; MAJOR GEOMAGNETIC STORMS; WIND STREAM INTERFACES; COSMIC-RAY DECREASES; ULYSSES OBSERVATIONS; DRIVER GAS AB While interplanetary coronal mass ejections (ICMEs) are understood to be the heliospheric counterparts of CMEs, with signatures undeniably linked to the CME process, the variability of these signatures and questions about mapping to observed CME features raise issues that remain on the cutting edge of ICME research. These issues are discussed in the context of traditional understanding, and recent results using innovative analysis techniques are reviewed. C1 Univ Kiel, Extraterrr Phys, Inst Expt & Angew Phys, Kiel, Germany. Boston Univ, Ctr Space Phys, Boston, MA USA. Univ London Imperial Coll Sci & Technol, Blackett Lab, London, England. Max Planck Inst Sonnensystemforsch, Lindau, Germany. San Jose State Univ Fdn, NASA Ames Res Ctr, Moffett Field, CA USA. Univ Colorado, Lab Atmospher & Space Physicsm, Boulder, CO USA. Int Space Sci Inst, Bern, Switzerland. NASA Goddard Space Flight Ctr, Greenbelt, MD USA. MIT, Cambridge, MA USA. Sci Applicat Int Corp, San Diego, CA USA. Univ Bern, Phys Inst, Bern, Switzerland. Univ Michigan, Dept Atmsoph Ocean & Space Sci, Ann Arbor, MI USA. RP Wimmer-Schweingruber, RF (reprint author), Univ Kiel, Extraterrr Phys, Inst Expt & Angew Phys, Kiel, Germany. EM wimmer@physik.uni-kiel.de RI Von Steiger, Rudolf/F-6822-2011; OI Von Steiger, Rudolf/0000-0002-3350-0023; Richardson, Ian/0000-0002-3855-3634 NR 198 TC 64 Z9 66 U1 1 U2 6 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 177 EP 216 DI 10.1007/s11214-006-9017-x PG 40 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400011 ER PT J AU Gopalswamy, N Mikic, Z Maia, D Alexander, D Cremades, H Kaufmann, P Tripathi, D Wang, YM AF Gopalswamy, N. Mikic, Z. Maia, D. Alexander, D. Cremades, H. Kaufmann, P. Tripathi, D. Wang, Y. -M. TI The Pre-CME sun SO SPACE SCIENCE REVIEWS LA English DT Article DE coronal mass ejections; flares; radio bursts; filaments; prominences; streamers; solar magnetism; active regions; closed and open magnetic fields; pre-eruption signatures; energy storage and release; helicity ID CORONAL MASS EJECTIONS; MAGNETIC-FLUX ROPE; SOLAR ACTIVE REGIONS; EMERGING FLUX; X-RAY; TRANSEQUATORIAL LOOPS; DIFFERENTIAL ROTATION; ERUPTIVE PROMINENCES; QUIESCENT FILAMENT; HELICITY INJECTION AB The coronal mass ejection (CME) phenomenon occurs in closed magnetic field regions on the Sun such as active regions, filament regions, transequatorial interconnection regions, and complexes involving a combination of these. This chapter describes the current knowledge on these closed field structures and how they lead to CMEs. After describing the specific magnetic structures observed in the CME source region, we compare the substructures of CMEs to what is observed before eruption. Evolution of the closed magnetic structures in response to various photospheric motions over different time scales (convection, differential rotation, meridional circulation) somehow leads to the eruption. We describe this pre-eruption evolution and attempt to link them to the observed features of CMEs. Small-scale energetic signatures in the form of electron acceleration (signified by nonthermal radio bursts at metric wavelengths) and plasma heating (observed as compact soft X-ray brightening) may be indicative of impending CMEs. We survey these pre-eruptive energy releases using observations taken before and during the eruption of several CMEs. Finally, we discuss how the observations can be converted into useful inputs to numerical models that can describe the CME initiation. C1 NASA Goddard Space Flight Ctr, Greenbelt, MD USA. SAIC, San Diego, CA 92121 USA. Fac Ciencias Univ, CICGE, Oporto, Portugal. Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. Max Planck Inst Solar Syst Res, D-37191 Katlenburg Duhm, Germany. Mackenzie Prebyteian Univ, CRAAM, Sao Paulo, Brazil. USN, Res Lab, Washington, DC USA. RP Gopalswamy, N (reprint author), NASA Goddard Space Flight Ctr, Greenbelt, MD USA. EM gopals@ssedmail.gsfc.nasa.gov RI Gopalswamy, Nat/D-3659-2012; Tripathi, Durgesh/D-9390-2012; OI Tripathi, Durgesh/0000-0003-1689-6254; Maia, Dalmiro/0000-0001-7855-1919 NR 157 TC 41 Z9 41 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 303 EP 339 DI 10.1007/s11214-006-9020-2 PG 37 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400014 ER PT J AU Pick, M Forbes, TG Mann, G Cane, HV Chen, J Ciaravella, A Cremades, H Howard, RA Hudson, HS Klassen, A Klein, KL Lee, MA Linker, JA Maia, D Mikic, Z Raymond, JC Reiner, MJ Simnett, GM Srivastava, N Tripathi, D Vainio, R Vourlidas, A Zhang, J Zurbuchen, TH Sheeley, NR Marque, C AF Pick, M. Forbes, T. G. Mann, G. Cane, H. V. Chen, J. Ciaravella, A. Cremades, H. Howard, R. A. Hudson, H. S. Klassen, A. Klein, K. L. Lee, M. A. Linker, J. A. Maia, D. Mikic, Z. Raymond, J. C. Reiner, M. J. Simnett, G. M. Srivastava, N. Tripathi, D. Vainio, R. Vourlidas, A. Zhang, J. Zurbuchen, T. H. Sheeley, N. R. Marque, C. TI Multi-wavelength observations of CMEs and associated phenomena SO SPACE SCIENCE REVIEWS LA English DT Article ID CORONAL MASS EJECTIONS; II RADIO-BURSTS; IMPULSIVE ELECTRON EVENTS; X-RAY OBSERVATIONS; MAGNETIC-FLUX ROPE; SOLAR-FLARE; SHOCK-WAVE; INTERPLANETARY MEDIUM; LASCO OBSERVATIONS; CURRENT SHEET AB This chapter reviews how our knowledge of CMEs and CME-associated phenomena has been improved, since the launch of the SOHO mission, thanks to multi-wavelength analysis. The combination of data obtained from space-based experiments and ground based instruments allows us to follow the space-time development of an event from the bottom of the corona to large distances in the interplanetary medium. Since CMEs originate in the low solar corona, understanding the physical processes that generate them is strongly dependant on coordinated multi-wavelength observations. CMEs display a large diversity in morphology and kinematic properties, but there is presently no statistical evidence that those properties may serve to group them into different classes. When a CME takes place, the coronal magnetic field undergoes restructuring. Much of the current research is focused on understanding how the corona sustains the stresses that allow the magnetic energy to build up and how, later on, this magnetic energy is released during eruptive flares and CMEs. Multi-wavelength observations have confirmed that reconnection plays a key role during the development of CMEs. Frequently, CMEs display a rather simple shape, exhibiting a well known three-part structure (bright leading edge, dark cavity and bright knot). These types of events have led to the proposal of the ''standard model'' of the development of a CME, a model which predicts the formation of current sheets. A few recent coronal observations provide some evidence for such sheets. Other more complex events correspond to multiple eruptions taking place on a time scale much shorter than the cadence of coronagraph instruments. They are often associated with large-scale dimming and coronal waves. The exact nature of these waves and the physical link between these different manifestations are not yet elucidated. We also discuss what kind of shocks are produced during a flare or a CME. Several questions remain unanswered. What is the nature of the shocks in the corona (blast-wave or piston-driven?) How they are related to Moreton waves seen in H alpha? How they are related to interplanetary shocks? The last section discusses the origin of energetic electrons detected in the corona and in the interplanetary medium. "Complex type III-like events,"which are detected at hectometric wavelengths, high in the corona, and are associated with CMEs, appear to originate from electrons that have been accelerated lower in the corona and not at the bow shock of CMEs. Similarly, impulsive energetic electrons observed in the interplanetary medium are not the exclusive result of electron acceleration at the bow shocks of CMEs; rather they have a coronal origin. C1 Observ Paris, CNRS, LESIA, UMR 8109, Meudon, France. Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH USA. Astrophys Inst Potsdam, Potsdam, Germany. NASA GSFC, Lab High Energy Astrophys, Greenbelt, MD USA. USN, Res Lab, Plasma Phys Div, Washington, DC USA. INAF Osserv Astron Palermo, Palermo, Italy. Max Planck Inst Sonnenforsch, Katlenburg Duhm, Germany. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Sci Applicat Int Corp, San Diego, CA USA. Univ Porto, Fac Ciencias, Observ Astron, CICGE, Vila Nova De Gaia, Portugal. Harvard Univ, Smithsonian Ctr Astrophys, Cambridge, MA USA. Catholic Univ Amer, Ctr Solar Phys & Space Weather, Washington, DC USA. NASA Goddard Space Flight Ctr, Greenbelt, MD USA. Univ Birmingham, Sch Phys & Space Res, Birmingham, W Midlands, England. Udaipur Solar Observ, Phys Res Lab, Udaipur, India. Univ Helsinki, Dept Phys Sci, Helsinki, Finland. George Mason Univ, Inst Computat Sci, Ctr Earth Observing & Space Res, Fairfield, VA USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI USA. RP Pick, M (reprint author), Observ Paris, CNRS, LESIA, UMR 8109, Meudon, France. EM monique.pick@obspm.fr RI Vainio, Rami/A-5590-2009; Vourlidas, Angelos/C-8231-2009; Tripathi, Durgesh/D-9390-2012 OI Vainio, Rami/0000-0002-3298-2067; Vourlidas, Angelos/0000-0002-8164-5948; Tripathi, Durgesh/0000-0003-1689-6254 NR 153 TC 31 Z9 31 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 341 EP 382 DI 10.1007/s11214-006-9021-1 PG 42 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400015 ER PT J AU Forsyth, RJ Bothmer, V Cid, C Crooker, NU Horbury, TS Kecskemety, K Klecker, B Linker, JA Odstrcil, D Reiner, MJ Richardson, IG Rodriguez-Pacheco, J Schmidt, JM Wimmer-Schweingruber, RF AF Forsyth, R. J. Bothmer, V. Cid, C. Crooker, N. U. Horbury, T. S. Kecskemety, K. Klecker, B. Linker, J. A. Odstrcil, D. Reiner, M. J. Richardson, I. G. Rodriguez-Pacheco, J. Schmidt, J. M. Wimmer-Schweingruber, R. F. TI ICMEs in the inner heliosphere: Origin, evolution and propagation effects SO SPACE SCIENCE REVIEWS LA English DT Article DE coronal mass ejections; magnetic clouds; solar wind; interplanetary shocks ID CORONAL MASS EJECTIONS; REMOTE RADIO TRACKING; COSMIC-RAY MODULATION; WIND MAGNETIC-FIELD; SOLAR-WIND; INTERPLANETARY SHOCKS; JANUARY 1997; GEOMAGNETIC STORMS; 3-DIMENSIONAL PROPAGATION; DOPPLER SCINTILLATION AB This report assesses the current status of research relating the origin at the Sun, the evolution through the inner heliosphere and the effects on the inner heliosphere of the interplanetary counterparts of coronal mass ejections (ICMEs). The signatures of ICMEs measured by in-situ spacecraft are determined both by the physical processes associated with their origin in the low corona, as observed by space-borne coronagraphs, and by the physical processes occurring as the ICMEs propagate out through the inner heliosphere, interacting with the ambient solar wind. The solar and in-situ observations are discussed as are efforts to model the evolution of ICMEs from the Sun out to 1 AU. C1 Univ London Imperial Coll Sci & Technol, Blackett Lab, London, England. Univ Gottingen, Inst Astrophys, Gottingen, Germany. Univ Alcala de Henares, Dpto Fis, Alcala Space Res Grp, Madrid, Spain. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. KFKI Res Inst Particle & Nucl Phys, Budapest, Hungary. MPI Extraterr Phys, Garching, Germany. SAIC, San Diego, CA USA. NOAA Space Environm Ctr, Boulder, CO USA. Catholic Univ Amer, Greenbelt, MD USA. NASA GSFC, Greenbelt, MD USA. NASA Goddard Space Flight Ctr, Greenbelt, MD USA. Int Univ Bremen, Bremen, Germany. Univ Kiel, Kiel, Germany. RP Forsyth, RJ (reprint author), Univ London Imperial Coll Sci & Technol, Blackett Lab, London, England. EM r.forsyth@imperial.ac.uk OI Richardson, Ian/0000-0002-3855-3634 NR 127 TC 45 Z9 46 U1 0 U2 9 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 383 EP 416 DI 10.1007/s11214-006-9022-0 PG 34 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400016 ER PT J AU Gazis, PR Balogh, A Dalla, S Decker, R Heber, B Horbury, T Kilchenmann, A Kota, J Kucharek, H Kunow, H Lario, D Potgieter, MS Richardson, JD Riley, P Rodriguez, L Siscoe, G Von Steiger, R AF Gazis, P. R. Balogh, A. Dalla, S. Decker, R. Heber, B. Horbury, T. Kilchenmann, A. Kota, J. Kucharek, H. Kunow, H. Lario, D. Potgieter, M. S. Richardson, J. D. Riley, P. Rodriguez, L. Siscoe, G. Von Steiger, R. TI ICMEs at high latitudes and in the outer heliosphere SO SPACE SCIENCE REVIEWS LA English DT Article DE ICMEs; outer heliosphere; coronal mass ejections ID CORONAL MASS EJECTIONS; COSMIC-RAY MODULATION; HIGH HELIOGRAPHIC LATITUDES; MERGED INTERACTION REGIONS; ENERGETIC PARTICLE OBSERVATIONS; 3-DIMENSIONAL MHD SIMULATION; SOLAR-WIND; MAGNETIC CLOUD; VOYAGER-2 OBSERVATIONS; DRIFT MODEL AB Interplanetary coronal mass ejections (ICMEs) propagate into the outer heliosphere, where they can have a significant effect on the structure, evolution, and morphology of the solar wind, particularly during times of high solar activity. They are known to play an important role in cosmic ray modulation and the acceleration of energetic particles. ICMEs are also believed to be associated with the large global transient events that swept through the heliosphere during the declining phases of solar cycles 21 and 22. But until recently, little was known about the actual behavior of ICMEs at large heliographic latitudes and large distances from the Sun. Over the past decade, the Ulysses spacecraft has provided in situ observations of ICMEs at moderate heliographic distances over a broad range of heliographic latitudes. More recently, observations of alpha particle enhancements, proton temperature depressions, and magnetic clouds at the Voyager and Pioneer spacecraft have begun to provide comparable information regarding the behavior of ICMEs at extremely large heliocentric distances. At the same time, advances in modeling have provided new insights into the dynamics and evolution of ICMEs and their effects on cosmic rays and energetic particles. C1 NASA Ames Res Ctr, SJSU Fdn, Moffett Field, CA USA. Univ London Imperial Coll Sci & Technol, London, England. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA. Univ Kiel, Kiel, Germany. Int Space Sci Inst, Bern, Switzerland. Univ Arizona, Tucson, AZ USA. Univ New Hampshire, Durham, NH 03824 USA. Potchefstroom Univ, Potchefstroom, South Africa. MIT, Ctr Space Res, Cambridge, MA USA. Sci Applicat Int Corp, San Diego, CA USA. Max Planck Inst Sonnensystemforsch, Katlenburg Duhm, Germany. Boston Univ, Boston, MA 02215 USA. RP Gazis, PR (reprint author), NASA Ames Res Ctr, SJSU Fdn, Moffett Field, CA USA. EM pgazis@mail.arc.nasa.gov RI Von Steiger, Rudolf/F-6822-2011; Lario, David/D-9318-2016 OI Von Steiger, Rudolf/0000-0002-3350-0023; Lario, David/0000-0002-3176-8704 NR 111 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 EI 1572-9672 J9 SPACE SCI REV JI Space Sci. Rev. PD MAR PY 2006 VL 123 IS 1-3 BP 417 EP 451 DI 10.1007/s11214-006-9023-z PG 35 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 109SH UT WOS:000242328400017 ER PT J AU DellaCorte, C AF DellaCorte, C TI Answers to tribology's most commonly asked questions 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 MAR PY 2006 VL 62 IS 3 BP 6 EP 6 PG 1 WC Engineering, Mechanical SC Engineering GA 024YE UT WOS:000236231700002 ER PT J AU Fry, JL Drouin, BJ Miller, CE AF Fry, JL Drouin, BJ Miller, CE TI Rotational spectroscopy and dipole moment of cis-cis HOONO and DOONO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PEROXYNITROUS ACID; AB-INITIO; SPECTRUM; DYNAMICS; DIOXIDE; STATES AB The rotational spectrum of cis-cis HOONO has been studied over a broad range of frequencies, 13-840 GHz, using pulsed beam Fourier-transform microwave spectroscopy and room-temperature flow cell submillimeter spectroscopy. The rotational spectrum of the deuterated isotopomer, cis-cis DOONO, has been studied over a subset of this range, 84-640 GHz. Improved spectroscopic constants have been determined for HOONO, and the DOONO spectrum is analyzed for the first time. Weak-field Stark effect measurements in the region of 84-110 GHz have been employed to determine the molecular dipole moments of cis-cis HOONO [mu(a)=0.542(8) D,mu(b)=0.918(15) D,mu=1.07(2) D] and DOONO [mu(a)=0.517(9) D,mu(b)=0.930(15) D,mu=1.06(2) D]. The quadrupole coupling tensor in the principal inertial axis system for the N-14 nucleus has been determined to be chi(aa)=1.4907(25) MHz,chi(bb)=-4.5990(59) MHz,chi(ab)=3.17(147) MHz, and chi(cc)=3.1082(59) MHz. Coordinates of the H atom in the center-of-mass frame have been determined with use of the Kraitchman equations, parallel to a(H)parallel to=0.516 A and parallel to b(H)parallel to=1.171 A. The inertial defects of HOONO and DOONO are consistent with a planar equilibrium structure with significant out-of-plane H atom torsional motion. Comparisons of the present results are made to ab initio calculations. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Arthur Amos Noyes Lab Chem Phys, Pasadena, CA 91125 USA. RP Drouin, BJ (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM brian.j.drouin@jpl.nasa.gov NR 29 TC 3 Z9 3 U1 1 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 28 PY 2006 VL 124 IS 8 AR 084304 DI 10.1063/1.2163341 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 016ZH UT WOS:000235663300019 PM 16512713 ER PT J AU Miserendino, S Yoo, J Cassell, A Tai, YC AF Miserendino, S Yoo, J Cassell, A Tai, YC TI Electrochemical characterization of parylene-embedded carbon nanotube nanoelectrode arrays SO NANOTECHNOLOGY LA English DT Article; Proceedings Paper CT International Conference on Bio-Nano-Informatics (BNI Fusion 2005) CY JUL 20-22, 2005 CL Marina del Rey, CA ID FABRICATION; ELECTRODES; ENSEMBLES AB A novel parylene-embedded carbon nanotube nanoelectrode array is presented for use as an electrochemical detector working electrode material. The fabrication process is compatible with standard microfluidic and other MEMS processing without requiring chemical mechanical polishing, Electrochemical studies of the nanoelectrodes showed that they perform comparably to platinum. Electrochemical pretreatment for short periods of time was found to further improve performance as measured by cathodic and anodic peak separation of K3Fe(CN)(6). A lower detection limit below 0.1 mu M was measured and with further fabrication improvements detection limits between 100 pM and 10 nM are possible. This makes the nanoelectrode arrays particularly suitable for trace electrochemical analysis. C1 CALTECH, Pasadena, CA 91125 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP CALTECH, 1200 E Calif Blvd, Pasadena, CA 91125 USA. EM scott@mems.caltech.edu NR 11 TC 18 Z9 18 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-4484 EI 1361-6528 J9 NANOTECHNOLOGY JI Nanotechnology PD FEB 28 PY 2006 VL 17 IS 4 BP S23 EP S28 DI 10.1088/0957-4484/17/4/005 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 020GL UT WOS:000235896600005 PM 21727350 ER PT J AU de Colstoun, ECB Walthall, CL AF de Colstoun, ECB Walthall, CL TI Improving global scale land cover classifications with multi-directional POLDER data and a decision tree classifier SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE global land cover; BRDF; decision tree ID REFLECTANCE DISTRIBUTION FUNCTION; BIDIRECTIONAL REFLECTANCE; DATA SET; FACTOR DISTRIBUTIONS; VEGETATION CANOPIES; SPATIAL-RESOLUTION; SATELLITE DATA; AVHRR DATA; SURFACE; MODEL AB Several investigations indicate that the Bidirectional Reflectance Distribution Function (BRDF) contains information that can be used to complement spectral information for improved land cover classification accuracies. Prior studies on the addition of BRDF information to improve land cover classifications have been conducted primarily at local or regional scales. Thus, the potential benefits of adding BRDF information to improve global to continental scale land cover classification have not yet been explored. Here we examine the impact of multidirectional global scale data from the first Polarization and Directionality of Earth Reflectances (POLDER) spacecraft instrument flown on the Advanced Earth Observing Satellite (ADEOS-1) platform on overall classification accuracy and per-class accuracies for 15 land cover categories specified by the International Geosphere Biosphere Programme (IGBP). A set of 36,648 global training pixels (7 x 6 km spatial resolution) was used with a decision tree classifier to evaluate the performance of classifying POLDER data with and without the inclusion of BRDF information. BRDF 'metrics' for the eight-month POWER on ADEOS-1 archive (10/1996-06/1997) were developed that describe the temporal evolution of the BRDF as captured by a semi-empirical BRDF model. The concept of BRDF 'feature space' is introduced and used to explore and exploit the bidirectional information content. The C5.0 decision tree classifier was applied with a boosting option, with the temporal metrics for spectral albedo as input for a first test, and with spectral albedo and BRDF metrics for a second test. Results were evaluated against 20 random subsets of the training data. Examination of the BRDF feature space indicates that coarse scale BRDF coefficients from POLDER provide information on land cover that is different from the spectral and temporal information of the imagery. The contribution of BRDF information to reducing classification errors is also demonstrated: the addition of BRDF metrics reduces the mean, overall classification error rates by 3.15% (from 18.1% to 14.95% error) with larger improvements for producer's accuracies of individual classes such as Grasslands (+8.71%), Urban areas (+8.02%), and Wetlands (+7.82%). User's accuracies for the Urban (+7.42%) and Evergreen Broadleaf Forest (+6.70%) classes are also increased. The methodology and results are widely applicable to current multidirectional satellite data from the Multi-angle Imaging Spectroradiometer (MISR), and to the next generation of POLDER-like multi-directional instruments. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. USDA ARS, Beltsville Agr Res Ctr, Hydrol & Remote Sensing Lab, Beltsville, MD 20705 USA. RP de Colstoun, ECB (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Sci Syst & Applicat Inc, Code 614-4, Greenbelt, MD 20771 USA. EM ericbdc@ltpmail.gsfc.nasa.gov NR 58 TC 26 Z9 26 U1 1 U2 21 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 FEB 28 PY 2006 VL 100 IS 4 BP 474 EP 485 DI 10.1016/j.rse.2005.11.003 PG 12 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 018GZ UT WOS:000235753700004 ER PT J AU Kimes, DS Ranson, KJ Sun, G Blair, JB AF Kimes, DS Ranson, KJ Sun, G Blair, JB TI Predicting lidar measured forest vertical structure from multi-angle spectral data SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE forest vertical structure; lidar; multi-angle; spectral; AirMISR; LVIS ID BIDIRECTIONAL REFLECTANCE; MULTIANGULAR MEASUREMENTS; LASER ALTIMETER; SAR IMAGES; VEGETATION; MISR; ATTRIBUTES; MODEL; UNIQUENESS; RETRIEVAL AB A capability to remotely measure the vertical and spatial distribution of forest structure is required for more accurate modeling of energy, carbon, water, and climate over regional, continental, and global scales. We examined the potential of using a multi-angle spectral sensor to predict forest vertical structure as measured by an airborne lidar system. Data were acquired from AirMISR (Airborne Multi-Angle Imaging Spectrometer) and airborne LVIS (Laser Vegetation Imaging Sensor) for a 7000 ha study site near Howland Maine, consisting of small plantations, multi-generation clearings and large natural forest stands. The LVIS data set provided a relatively direct measure of forest vertical structure at a fine scale (20 m diameter footprints). Multivariate linear regression and neural network models were developed to predict the LVIS forest energy height measures from 28 AirMISR multi-angle spectral radiance values. The best model accurately predicted the maximum canopy height (as measured from LVIS) using AirMISR data (rmse-0.92 m, R-2 =0.89). The models developed in this study achieved high accuracies over a study site with an elaborate patchwork of forest communities with exceptional diversity in forest structure. We conclude that models using MISR-like data are capable of accurately predicting the vertical structure of forest canopies. Published by Elsevier Inc. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Maryland, Dept Geog, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Laser Remote Sensing Lab, Greenbelt, MD 20771 USA. RP Kimes, DS (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Code 614-4, Greenbelt, MD 20771 USA. EM dan@pika.gsfc.nasa.gov RI Ranson, Kenneth/G-2446-2012; Blair, James/D-3881-2013; Beckley, Matthew/D-4547-2013 OI Ranson, Kenneth/0000-0003-3806-7270; NR 33 TC 59 Z9 68 U1 2 U2 14 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 FEB 28 PY 2006 VL 100 IS 4 BP 503 EP 511 DI 10.1016/j.rse.2005.11.004 PG 9 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 018GZ UT WOS:000235753700006 ER PT J AU Verma, V Simmons, R AF Verma, V Simmons, R TI Scalable robot fault detection and identification SO ROBOTICS AND AUTONOMOUS SYSTEMS LA English DT Article; Proceedings Paper CT 8th Conference on Intelligent Autonomous Systems (IAS-8) CY MAR 10-13, 2005 CL Amsterdam, NETHERLANDS DE robot fault diagnosis; fault protection; robot fault detection AB Experience has shown that even carefully designed and tested robots may encounter anomalous situations. It is therefore important for robots to monitor their state so that anomalous situations may be detected in a timely manner. Robot fault diagnosis typically requires tracking a very large number of possible faults in complex non-linear dynamic systems with noisy sensors. Traditional methods either ignore the uncertainty or use linear approximations of non-linear system dynamics. Such approximations are often unrealistic, and as a result faults either go undetected or become confused with non-fault conditions. Probability theory provides a natural representation for uncertainty, but an exact Bayesian solution for the diagnosis problem is intractable. Monte Carlo approximations have demonstrated considerable success in application domains such as computer vision and robot localization and mapping. But, classical Monte Carlo methods, such as particle filters, can suffer from substantial computational complexity. This is particularly true with the presence of rare, yet important events, such as many system faults. This paper presents an algorithm that provides an approach for computationally tractable fault diagnosis. Taking advantage of structure in the domain it dynamically concentrates computation in the regions of state space that are currently most relevant without losing track of less likely states. Experiments with a dynamic simulation of a six-wheel rocker-bogie rover show a significant improvement in performance over the classical approach. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94043 USA. Carnegie Mellon Univ, Robens Inst, Pittsburgh, PA 15213 USA. RP Verma, V (reprint author), NASA, Ames Res Ctr, MS 269-1, Moffett Field, CA 94043 USA. EM vandi@email.arc.nasa.gov; reids@ri.cmu.edu OI Simmons, Reid/0000-0003-3153-0453 NR 23 TC 13 Z9 14 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8890 J9 ROBOT AUTON SYST JI Robot. Auton. Syst. PD FEB 28 PY 2006 VL 54 IS 2 BP 184 EP 191 DI 10.1016/j.robot.2005.09.028 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Robotics SC Automation & Control Systems; Computer Science; Robotics GA 011GT UT WOS:000235256900013 ER PT J AU Wei, CY AF Wei, CY TI Adhesion and reinforcement in carbon nanotube polymer composite SO APPLIED PHYSICS LETTERS LA English DT Article ID POLYSTYRENE; SIMULATION; STRENGTH; FILMS AB Temperature dependent adhesion behavior and reinforcement in carbon nanotube (CNT)-polymer (polyethylene) composite is studied through molecular dynamics simulations. The interfacial shear stress through van der Waals interactions is found to increase linearly with applied tensile strains along the nanotube axis direction, until the noncovalent bonds between CNTs and molecules break successively. A lower bound value about 46 MPa is found for the shear strength at low temperatures. Direct stress-strain calculations show significant reinforcements in the composite in a wide temperature range, with similar to 200% increase in the Young's modulus when adding 6.5% volume ratio of short CNTs, and comparisons with the Halpin-Tsai formula are discussed. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Wei, CY (reprint author), NASA, Ames Res Ctr, MS 229-1, Moffett Field, CA 94035 USA. EM cwei@mail.arc.nasa.gov NR 22 TC 47 Z9 47 U1 3 U2 15 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 FEB 27 PY 2006 VL 88 IS 9 AR 093108 DI 10.1063/1.2181188 PG 3 WC Physics, Applied SC Physics GA 018AY UT WOS:000235736300074 ER PT J AU Popp, PJ Marcy, TP Jensen, EJ Karcher, B Fahey, DW Gao, RS Thompson, TL Rosenlof, KH Richard, EC Herman, RL Weinstock, EM Smith, JB May, RD Vomel, H Wilson, JC Heymsfield, AJ Mahoney, MJ Thompson, AM AF Popp, PJ Marcy, TP Jensen, EJ Karcher, B Fahey, DW Gao, RS Thompson, TL Rosenlof, KH Richard, EC Herman, RL Weinstock, EM Smith, JB May, RD Vomel, H Wilson, JC Heymsfield, AJ Mahoney, MJ Thompson, AM TI The observation of nitric acid-containing particles in the tropical lower stratosphere SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID LARGE HNO3-CONTAINING PARTICLES; TROPOPAUSE CLOUDS UTTCS; IN-SITU MEASUREMENTS; UPPER TROPOSPHERE; POLAR STRATOSPHERE; ARCTIC DENITRIFICATION; MICROPHYSICAL MODEL; RELATIVE-HUMIDITY; REACTIVE NITROGEN; TRIHYDRATE NAT AB Airborne in situ measurements over the eastern Pacific Ocean in January 2004 have revealed a new category of nitric acid (HNO3)-containing particles in the tropical lower stratosphere. These particles are most likely composed of nitric acid trihydrate (NAT). They were intermittently observed in a narrow layer above the tropopause ( 18 +/- 0.1 km) and over a broad geographic extent (> 1100 km). In contrast to the background liquid sulfate aerosol, these particles are solid, much larger ( 1.7 - 4.7 mu m vs. 0.1 mu m in diameter), and significantly less abundant (< 10(-4) cm(-3) vs. 10 cm(-3)). Microphysical trajectory models suggest that the NAT particles grow over a 6 - 14 day period in supersaturated air that remains close to the tropical tropopause and might be a common feature in the tropics. The small number density of these particles implies a highly selective or slow nucleation process. Understanding the formation of solid NAT particles in the tropics could improve our understanding of stratospheric nucleation processes and, therefore, dehydration and denitrification. C1 NOAA, Div Chem Sci, Earth Syst Res Lab, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Deutsch Zentrum Luft & Raumfahrt, Inst Phys Atmosphare, Oberpfaffenhofen, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Harvard Univ, Atmospher Res Project, Cambridge, MA 02138 USA. MayComm Instruments, San Dimas, CA 91773 USA. NOAA, Global Monitoring Div, Earth Syst Res Lab, Boulder, CO 80305 USA. Univ Denver, Dept Engn, Denver, CO 80208 USA. Natl Ctr Atmospher Res, Mesoscale & Microscale Meteorol Div, Boulder, CO 80301 USA. Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. RP NOAA, Div Chem Sci, Earth Syst Res Lab, Boulder, CO 80305 USA. EM peter.j.popp@noaa.gov RI Fahey, David/G-4499-2013; Thompson, Anne /C-3649-2014; Heymsfield, Andrew/E-7340-2011; Rosenlof, Karen/B-5652-2008; Herman, Robert/H-9389-2012; Gao, Ru-Shan/H-7455-2013; Karcher, Bernd/D-5325-2014 OI Fahey, David/0000-0003-1720-0634; Thompson, Anne /0000-0002-7829-0920; Rosenlof, Karen/0000-0002-0903-8270; Herman, Robert/0000-0001-7063-6424; Karcher, Bernd/0000-0003-0278-4980 NR 46 TC 18 Z9 18 U1 0 U2 3 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 FEB 27 PY 2006 VL 6 BP 601 EP 611 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 015KS UT WOS:000235550900001 ER PT J AU Yu, H Kaufman, YJ Chin, M Feingold, G Remer, LA Anderson, TL Balkanski, Y Bellouin, N Boucher, O Christopher, S DeCola, P Kahn, R Koch, D Loeb, N Reddy, MS Schulz, M Takemura, T Zhou, M AF Yu, H Kaufman, YJ Chin, M Feingold, G Remer, LA Anderson, TL Balkanski, Y Bellouin, N Boucher, O Christopher, S DeCola, P Kahn, R Koch, D Loeb, N Reddy, MS Schulz, M Takemura, T Zhou, M TI A review of measurement-based assessments of the aerosol direct radiative effect and forcing SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Review ID DUST EXPERIMENT SHADE; ROTATING SHADOWBAND RADIOMETER; SKY RADIANCE MEASUREMENTS; EXPLORATORY MISSION-WEST; SINGLE-SCATTERING ALBEDO; BIOMASS BURNING AEROSOLS; INDIAN-OCEAN EXPERIMENT; SOUTHERN GREAT-PLAINS; IN-SITU MEASUREMENTS; GLOBAL-MODEL GOCART AB Aerosols affect the Earth's energy budget directly by scattering and absorbing radiation and indirectly by acting as cloud condensation nuclei and, thereby, affecting cloud properties. However, large uncertainties exist in current estimates of aerosol forcing because of incomplete knowledge concerning the distribution and the physical and chemical properties of aerosols as well as aerosol-cloud interactions. In recent years, a great deal of effort has gone into improving measurements and datasets. It is thus feasible to shift the estimates of aerosol forcing from largely model-based to increasingly measurement-based. Our goal is to assess current observational capabilities and identify uncertainties in the aerosol direct forcing through comparisons of different methods with independent sources of uncertainties. Here we assess the aerosol optical depth (tau), direct radiative effect (DRE) by natural and anthropogenic aerosols, and direct climate forcing (DCF) by anthropogenic aerosols, focusing on satellite and ground-based measurements supplemented by global chemical transport model CTM) simulations. The multi-spectral MODIS measures global distributions of aerosol optical depth (tau) on a daily scale, with a high accuracy of +/- 0.03 +/- 0.05 tau over ocean. The annual average tau is about 0.14 over global ocean, of which about 21% +/- 7% is contributed by human activities, as estimated by MODIS fine-mode fraction. The multi-angle MISR derives an annual average AOD of 0.23 over global land with an uncertainty of similar to 20% or +/- 0.05. These high-accuracy aerosol products and broadband flux measurements from CERES make it feasible to obtain observational constraints for the aerosol direct effect, especially over global the ocean. A number of measurement-based approaches estimate the clear-sky DRE ( on solar radiation) at the top-of-atmosphere (TOA) to be about - 5.5 +/- 0.2 W m(-2) ( median +/- standard error from various methods) over the global ocean. Accounting for thin cirrus contamination of the satellite derived aerosol field will reduce the TOA DRE to -5.0 W m(-2). Because of a lack of measurements of aerosol absorption and difficulty in characterizing land surface reflection, estimates of DRE over land and at the ocean surface are currently realized through a combination of satellite retrievals, surface measurements, and model simulations, and are less constrained. Over the oceans the surface DRE is estimated to be - 8.8 +/- 0.7W m(-2). Over land, an integration of satellite retrievals and model simulations derives a DRE of - 4.9 +/- 0.7W m(-2) and - 11.8 +/- 1.9W m(-2) at the TOA and surface, respectively. CTM simulations derive a wide range of DRE estimates that on average are smaller than the measurement-based DRE by about 30 - 40%, even after accounting for thin cirrus and cloud contamination. A number of issues remain. Current estimates of the aerosol direct effect over land are poorly constrained. Uncertainties of DRE estimates are also larger on regional scales than on a global scale and large discrepancies exist between different approaches. The characterization of aerosol absorption and vertical distribution remains challenging. The aerosol direct effect in the thermal infrared range and in cloudy conditions remains relatively unexplored and quite uncertain, because of a lack of global systematic aerosol vertical profile measurements. A coordinated research strategy needs to be developed for integration and assimilation of satellite measurements into models to constrain model simulations. Enhanced measurement capabilities in the next few years and high-level scientific cooperation will further advance our knowledge. C1 Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Washington, Seattle, WA 98195 USA. CEA, CNRS, LSCE, Lorme Des Merisiers, France. Met Off, Exeter, Devon, England. Univ Lille 1, Opt Atmospher Lab, F-59655 Villeneuve Dascq, France. Univ Alabama, Huntsville, AL 35899 USA. NASA Headquarters, Washington, DC USA. NASA, Jet Propuls Lab, Pasadena, CA USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. NASA, Langley Atmospher Res Ctr, Hampton, VA USA. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ USA. Kyushu Univ, Fukuoka 812, Japan. Georgia Inst Technol, Atlanta, GA 30332 USA. NOAA, Environm Technol Lab, Boulder, CO USA. RP Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. EM hyu@climate.gsfc.nasa.gov RI Yu, Hongbin/C-6485-2008; Christopher, Sundar/E-6781-2011; Takemura, Toshihiko/C-2822-2009; Boucher, Olivier/J-5810-2012; Boucher, Olivier/K-7483-2012; Chin, Mian/J-8354-2012; Feingold, Graham/B-6152-2009; Balkanski, Yves/A-6616-2011; Kahn, Ralph/D-5371-2012; Schulz, Michael/A-6930-2011; U-ID, Kyushu/C-5291-2016; Kyushu, RIAM/F-4018-2015 OI Yu, Hongbin/0000-0003-4706-1575; Takemura, Toshihiko/0000-0002-2859-6067; Boucher, Olivier/0000-0003-2328-5769; Boucher, Olivier/0000-0003-2328-5769; Balkanski, Yves/0000-0001-8241-2858; Kahn, Ralph/0000-0002-5234-6359; Schulz, Michael/0000-0003-4493-4158; NR 281 TC 359 Z9 369 U1 23 U2 129 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 FEB 27 PY 2006 VL 6 BP 613 EP 666 PG 54 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 016KI UT WOS:000235618700001 ER PT J AU Morscher, GN Singh, M Shpargel, T Asthana, R AF Morscher, GN Singh, M Shpargel, T Asthana, R TI A simple test to determine the effectiveness of different braze compositions for joining Ti-tubes to C/C composite plates SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE joining; mechanical properties; C/C-Ti AB A simple tube-plate joint tensile test was implemented to compare the effectiveness of commercial brazes, namely, TiCuNi, TiCuSil, and Cu-ABA, used for bonding Ti-tubes to C-C composite plates. The three braze systems yielded different; yet, repeatable results. The Cu-ABA system proved to have about twice the load-carrying ability of the other two systems due to the fact that the bonded area between the braze material and the C-C plate was largest for this system. The orientation of the surface fiber tows also had a significant effect on load-carrying ability with tows oriented perpendicular to the tube axis displaying the highest failure loads. Increasing the process load and modifying the surface of the C-C plate by grooving out channels for the Ti-tube to nest in resulted in increased load-carrying ability for the TiCuSil and Cu-ABA systems due to increased bonded area and better penetration of the braze material into the C-C composite. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, QSS Grp Inc, Cleveland, OH 44135 USA. Univ Wisconsin, Dept Technol, Menomonie, WI USA. RP Morscher, GN (reprint author), NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. EM gmorscher@grc.nasa.gov NR 6 TC 24 Z9 25 U1 4 U2 10 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 FEB 25 PY 2006 VL 418 IS 1-2 BP 19 EP 24 DI 10.1016/j.msea.2005.10.067 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 018MV UT WOS:000235769400003 ER PT J AU Huang, GL Nakajima, H Masuda, S Kobayashi, K Kubo, M AF Huang, GL Nakajima, H Masuda, S Kobayashi, K Kubo, M TI Source structures of the 1998 November 28 X-class flare and electron acceleration SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN LA English DT Article DE sun : flares; sun : radio radiation; sun : X-rays, gamma rays ID SOLAR-A MISSION; MAGNETIC RECONNECTION; RAY TELESCOPE; MODEL; YOHKOH; LOOPS AB We studied the 1998 November 28 X-class flare, which showed long-duration, two-ribbon H alpha emission. (1) A soft X-ray loop system developed along the major magnetic neutral line in the impulsive phase. Hard X-ray and microwave emissions due to nonthermal electrons were located in some limited regions. While the compact hard X-ray loop was associated with weak, diffuse soft X-ray emission, two large microwave loops did not have soft X-ray counterparts. (2) Time profiles of two large microwave loops were similar to that of hard X-ray total emission, which emanated mostly from the compact Source, even in the fine time Structure in the rising phase. (3) A super-hot thermal hard X-ray source appeared around the impulsive peak and was located along the major magnetic neutral line in the declining phase, coinciding with the bright soft X-ray emission. The thermal component can be explained within the standard reconnection model to the extent that the super-hot thermal plasma was heated in the large soft X-ray loop. However, the nonthermal electrons were accelerated in a localized region where three loops interacted with each other. The inferred configuration may be a more complicated form of the double-loop interaction model proposed by Hanaoka (1996) and Nishio et al. (1997). C1 Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China. Natl Astron Observ, Nagano 3841305, Japan. Nagoya Univ, Solar Terrestrial Environm Lab, Aichi 4428507, Japan. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Tokyo, Dept Astron, Tokyo 1130033, Japan. RP Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China. EM glhuang@pmo.ac.cn NR 27 TC 2 Z9 2 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 FEB 25 PY 2006 VL 58 IS 1 BP 37 EP 45 DI 10.1093/pasj/58.1.37 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 019PO UT WOS:000235849400006 ER PT J AU Fung, SF Shao, X Tan, LC AF Fung, SF Shao, X Tan, LC TI Long-term variations of the electron slot region and global radiation belt structure SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EARTHS INNER MAGNETOSPHERE; SCATTERING LOSS; PRECIPITATION; PLASMASPHERE AB We report the observations of changes of the nominal position of the quiet-time radiation belt slot over the solar cycles. It has been found that the slot region, believed to be a result of enhanced precipitation losses of energetic electrons due to their interactions with VLF waves in the magnetosphere, tends to shift to higher L (similar to 3) during a solar maximum compared to its canonical L value of similar to 2.5, which is more typical of a solar minimum. The solar-cycle migration of the slot can be understood in terms of the solar-cycle changes in ionospheric densities, which may cause the optimal wave-particle interaction region during higher solar activity periods to move to higher altitudes and higher latitudes, thus higher L. Our analysis also suggests that the primary regions of wave-particle interaction processes that result in the slot formation are located off of the magnetic equator. C1 NASA, Goddard Space Flight Ctr, Space Phys Data Facil, Greenbelt, MD 20771 USA. Natl Acad Sci, Natl Res Council, Washington, DC 20418 USA. QSS Grp Inc, Lanham, MD USA. RP Fung, SF (reprint author), NASA, Goddard Space Flight Ctr, Space Phys Data Facil, Code 632, Greenbelt, MD 20771 USA. EM shing.f.fung@nasa.gov RI Fung, Shing/F-5647-2012 NR 21 TC 14 Z9 14 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 FEB 22 PY 2006 VL 33 IS 4 AR L04105 DI 10.1029/2005GL024891 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 021DY UT WOS:000235965100004 ER PT J AU Wu, LG Braun, SA Qu, JJ Hao, XJ AF Wu, LG Braun, SA Qu, JJ Hao, XJ TI Simulating the formation of Hurricane Isabel (2003) with AIRS data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NUMERICAL SIMULATIONS; PART I; LAYER; DISTURBANCES; ATLANTIC; MODEL; AREA AB Using the AIRS retrieved temperature and humidity profiles, the Saharan Air Layer (SAL) influence on the formation of Hurricane Isabel (2003) is simulated numerically with the MM5 model. The warmth and dryness of the SAL (the thermodynamic effect) is assimilated by use of the nudging technique, which enables the model thermodynamic state to be relaxed to the profiles of the AIRS retrieved data for the regions without cloud contamination. By incorporating the AIRS data, MM5 better simulates the large-scale flow patterns and the timing and location of the formation of Hurricane Isabel and its subsequent track. By comparing with an experiment without nudging of the AIRS data, it is shown that the SAL may have delayed the formation of Hurricane Isabel and inhibited the development of another tropical disturbance to the east. This case study confirms the argument by Dunion and Velden (2004) that the SAL can suppress Atlantic tropical cyclone activity by increasing the vertical wind shear, reducing the mean relative humidity, and stabilizing the environment at lower levels. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Mesoscale Atmospher Proc Branch, Greenbelt, MD 20071 USA. Univ Maryland, Goddard Earth & Technol Ctr, Baltimore, MD 21201 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. George Mason Univ, Sch Computat Sci, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA. RP Wu, LG (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Mesoscale Atmospher Proc Branch, Code 613-1, Greenbelt, MD 20071 USA. EM liguang@agnes.gsfc.nasa.gov 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 16 TC 56 Z9 63 U1 0 U2 0 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 FEB 22 PY 2006 VL 33 IS 4 AR L04804 DI 10.1029/2005GL024665 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 021DY UT WOS:000235965100002 ER PT J AU Gasparini, R Li, RJ Collins, DR Ferrare, RA Brackett, VG AF Gasparini, R Li, RJ Collins, DR Ferrare, RA Brackett, VG TI Application of aerosol hygroscopicity measured at the Atmospheric Radiation Measurement Program's Southern Great Plains site to examine composition and evolution SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID DIFFERENTIAL MOBILITY ANALYZER; SIZE DISTRIBUTIONS; PARTICLE-SIZE; WATER-VAPOR; LOS-ANGELES; BEHAVIOR; CLOUD; FRACTIONS; PROFILES AB A Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) was used to measure submicron aerosol size distributions, hygroscopicity, and occasionally volatility during the May 2003 Aerosol Intensive Operational Period (IOP) at the Central Facility of the Atmospheric Radiation Measurement Program's Southern Great Plains (ARM SGP) site. Hygroscopic growth factor distributions for particles at eight dry diameters ranging from 0.012 mu m to 0.600 mu m were measured throughout the study. For a subset of particle sizes, more detailed measurements were occasionally made in which the relative humidity or temperature to which the aerosol was exposed was varied over a wide range. These measurements, in conjunction with backtrajectory clustering, were used to infer aerosol composition and to gain insight into the processes responsible for evolution. The hygroscopic growth of both the smallest and largest particles analyzed was typically less than that of particles with dry diameters of about 0.100 mu m. It is speculated that condensation of secondary organic aerosol on nucleation mode particles is largely responsible for the minimal hygroscopic growth observed at the smallest sizes considered. Growth factor distributions of the largest particles characterized typically contained a nonhygroscopic mode believed to be composed primarily of dust. A model was developed to characterize the hygroscopic properties of particles within a size distribution mode through analysis of the fixed size hygroscopic growth measurements. The performance of this model was quantified through comparison of the measured fixed size hygroscopic growth factor distributions with those simulated through convolution of the size-resolved concentration contributed by each of the size modes and the mode-resolved hygroscopicity. This transformation from size-resolved hygroscopicity to mode-resolved hygroscopicity facilitated examination of changes in the hygroscopic properties of particles within a size distribution mode that accompanied changes in the sizes of those particles. This model was used to examine three specific cases in which the sampled aerosol evolved slowly over a period of hours or days. C1 Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. NASA, Langley Res Ctr, Sci Applicat Int Corp, Hampton, VA 23681 USA. RP Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. EM dcollins@tamu.edu RI Li, Runjun/F-2694-2012; Collins, Don/F-9617-2012 NR 30 TC 20 Z9 20 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 FEB 22 PY 2006 VL 111 IS D5 AR D05S12 DI 10.1029/2004JD005448 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 021ES UT WOS:000235967100001 ER PT J AU Cabrol, NA Farmer, JD Grin, EA Richter, L Soderblom, L Li, R Herkenhoff, K Landis, GA Arvidson, RE AF Cabrol, NA Farmer, JD Grin, EA Richter, L Soderblom, L Li, R Herkenhoff, K Landis, GA Arvidson, RE TI Aqueous processes at Gusev crater inferred from physical properties of rocks and soils along the Spirit traverse SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MAADIM-VALLIS; MARS; ROVER; WATER; SPECTROMETER; PALEOLAKE; DEPOSITS; VALLEYS; IMAGES AB Gusev crater was selected as the landing site for Spirit on the basis of morphological evidence of long-lasting water activity, including possibly fluvial and lacustrine episodes. From the Columbia Memorial Station to the Columbia Hills, Spirit's traverse provides a journey back in time, from relatively recent volcanic plains showing little evidence for aqueous processes up to the older hills, where rock and soil composition are drastically different. For the first 156 sols, the only evidence of water action was weathering rinds, vein fillings, and soil crust cementation by salts. The trenches of Sols 112 - 145 marked the first significant findings of increased concentrations of sulfur and magnesium varying in parallel, suggesting that they be paired as magnesium-sulfate. Spirit's arrival at West Spur coincided with a shift in rock and soil composition with observations hinting at substantial amounts of water in Gusev's past. We used the Microscopic Imager data up to Sol 431 to analyze rock and soil properties and infer plausible types and magnitude of aqueous processes through time. We show the role played early by topography and structure. The morphology, texture, and deep alteration shown by the rocks in West Spur and the Columbia Hills Formation (CHF) suggest conditions that are not met in present-day Mars and required a wetter environment, which could have included transport of sulfur, chlorine, and bromine in water, vapor in volcanic gases, hydrothermal circulation, or saturation in a briny fluid containing the same elements. Changing conditions that might have affected flow circulation are suggested by different textural and morphological characteristics between the rocks in the CHF and those of the plains, with higher porosity proxy, higher void ratio, and higher water storage potential in the CHF. Soils were used to assess aqueous processes and water pathways in the top layers of modern soils. We conclude that infiltration might have become more difficult with time. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. US Geol Survey, Flagstaff, AZ 86001 USA. NASA, John Glenn Res Ctr, Photovolta & Space Environm Branch, Cleveland, OH 44135 USA. Ohio State Univ, Dept Civil & Environm Engn & Geodet Sci, Columbus, OH 43210 USA. DLR, Inst Raumsimulat, D-51170 Cologne, Germany. RP NASA, Ames Res Ctr, Div Space Sci, MS 245-3, Moffett Field, CA 94035 USA. EM ncabrol@mail.arc.nasa.gov NR 54 TC 17 Z9 18 U1 0 U2 6 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 FEB 22 PY 2006 VL 111 IS E2 AR E02S20 DI 10.1029/2005JE002490 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 021FD UT WOS:000235968200001 ER PT J AU Morris, RV Klingelhofer, G Schroder, C Rodionov, DS Yen, A Ming, DW de Souza, PA Fleischer, I Wdowiak, T Gellert, R Bernhardt, B Evlanov, EN Zubkov, B Foh, J Bonnes, U Kankeleit, E Gutlich, P Renz, F Squyres, SW Arvidson, RE AF Morris, RV Klingelhofer, G Schroder, C Rodionov, DS Yen, A Ming, DW de Souza, PA Fleischer, I Wdowiak, T Gellert, R Bernhardt, B Evlanov, EN Zubkov, B Foh, J Bonnes, U Kankeleit, E Gutlich, P Renz, F Squyres, SW Arvidson, RE TI Mossbauer mineralogy of rock, soil, and dust at Gusev crater, Mars: Spirit's journey through weakly altered olivine basalt on the plains and pervasively altered basalt in the Columbia Hills SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MAGNETIC-PROPERTIES EXPERIMENTS; HAWAIIAN PALAGONITIC SOIL; IMPACT MELT; X-RAY; ROVER; HEMATITE; QUEBEC; SPECTROMETER; SPECTROSCOPY; ALPHA-FE2O3 AB The Mossbauer spectrometer on Spirit measured the oxidation state of Fe, identified Fe-bearing phases, and measured relative abundances of Fe among those phases for surface materials on the plains and in the Columbia Hills of Gusev crater. Eight Fe-bearing phases were identified: olivine, pyroxene, ilmenite, magnetite, nanophase ferric oxide (npOx), hematite, goethite, and a Fe3+-sulfate. Adirondack basaltic rocks on the plains are nearly unaltered (Fe3+/Fe-T < 0.2) with Fe from olivine, pyroxene ( Ol > Px), and minor npOx and magnetite. Columbia Hills basaltic rocks are nearly unaltered ( Peace and Backstay), moderately altered (WoolyPatch, Wishstone, and Keystone), and pervasively altered ( e. g., Clovis, Uchben, Watchtower, Keel, and Paros with Fe3+/Fe-T similar to 0.6 - 0.9). Fe from pyroxene is greater than Fe from olivine ( Ol sometimes absent), and Fe2+ from Ol + Px is 40 - 49% and 9 - 24% for moderately and pervasively altered materials, respectively. Ilmenite ( Fe from Ilm similar to 3 - 6%) is present in Backstay, Wishstone, Keystone, and related rocks along with magnetite ( Fe from Mt similar to 10 - 15%). Remaining Fe is present as npOx, hematite, and goethite in variable proportions. Clovis has the highest goethite content ( Fe from Gt = 40%). Goethite (alpha-FeOOH) is mineralogical evidence for aqueous processes because it has structural hydroxide and is formed under aqueous conditions. Relatively unaltered basaltic soils (Fe3+/FeT similar to 0.3) occur throughout Gusev crater ( similar to 60 - 80% Fe from Ol + Px, similar to 10 - 30% from npOx, and similar to 10% from Mt). PasoRobles soil in the Columbia Hills has a unique occurrence of high concentrations of Fe3+-sulfate ( similar to 65% of Fe). Magnetite is identified as a strongly magnetic phase in Martian soil and dust. C1 NASA, Johnson Space Ctr, Houston, TX 77058 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Johannes Gutenberg Univ Mainz, Inst Anorgan & Analyt Chem, D-55128 Mainz, Germany. Tech Univ Darmstadt, D-64289 Darmstadt, Germany. Space Res Inst, IKI, Moscow 117997, Russia. Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. Cornell Univ, Ctr Radiophys & Space Res, Ithaca, NY 14853 USA. Univ Alabama Birmingham, Dept Phys, Birmingham, AL 35294 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP NASA, Johnson Space Ctr, Mail Code SN3, Houston, TX 77058 USA. EM richard.v.morris@nasa.gov RI de Souza, Paulo/B-8961-2008; Schroder, Christian/B-3870-2009 OI de Souza, Paulo/0000-0002-0091-8925; Schroder, Christian/0000-0002-7935-6039 NR 56 TC 217 Z9 217 U1 8 U2 31 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 FEB 22 PY 2006 VL 111 IS E2 AR E02S13 DI 10.1029/2005JE002584 PG 28 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 021FD UT WOS:000235968200002 ER PT J AU Wang, A Haskin, LA Squyres, SW Jolliff, BL Crumpler, L Gellert, R Schroder, C Herkenhoff, K Hurowitz, J Tosca, NJ Farrand, WH Anderson, R Knudson, AT AF Wang, A Haskin, LA Squyres, SW Jolliff, BL Crumpler, L Gellert, R Schroder, C Herkenhoff, K Hurowitz, J Tosca, NJ Farrand, WH Anderson, R Knudson, AT TI Sulfate deposition in subsurface regolith in Gusev crater, Mars SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID HUMIDITY-BUFFER TECHNIQUE; SPIRIT ROVER; MOSSBAUER SPECTROMETER; NEAR-SURFACE; 0.1 MPA; ROCKS; SOILS; MINERALOGY; WATER; DISSOLUTION AB Excavating into the shallow Martian subsurface has the potential to expose stratigraphic layers and mature regolith, which may hold a record of more ancient aqueous interactions than those expected under current Martian surface conditions. During the Spirit rover's exploration of Gusev crater, rover wheels were used to dig three trenches into the subsurface regolith down to 6 - 11 cm depth: Road Cut, the Big Hole, and The Boroughs. A high oxidation state of Fe and high concentrations of Mg, S, Cl, and Br were found in the subsurface regolith within the two trenches on the plains, between the Bonneville crater and the foot of Columbia Hills. Data analyses on the basis of geochemistry and mineralogy observations suggest the deposition of sulfate minerals within the subsurface regolith, mainly Mg-sulfates accompanied by minor Ca-sulfates and perhaps Fe-sulfates. An increase of Fe2O3, an excess of SiO2, and a minor decrease in the olivine proportion relative to surface materials are also inferred. Three hypotheses are proposed to explain the geochemical trends observed in trenches: ( 1) multiple episodes of acidic fluid infiltration, accompanied by in situ interaction with igneous minerals and salt deposition; ( 2) an open hydrologic system characterized by ion transportation in the fluid, subsequent evaporation of the fluid, and salt deposition; and ( 3) emplacement and mixing of impact ejecta of variable composition. While all three may have plausibly contributed to the current state of the subsurface regolith, the geochemical data are most consistent with ion transportation by fluids and salt deposition as a result of open-system hydrologic behavior. Although sulfates make up > 20 wt.% of the regolith in the wall of The Boroughs trench, a higher hydrated sulfate than kieserite within The Boroughs or a greater abundance of sulfates elsewhere than is seen in The Boroughs wall regolith would be needed to hold the structural water indicated by the water-equivalent hydrogen concentration observed by the Gamma-Ray Spectrometer on Odyssey in the Gusev region. C1 Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. New Mexico Museum Nat Hist & Sci, Albuquerque, NM 87104 USA. Max Planck Inst Chem, Abt Kosmochem, D-55020 Mainz, Germany. Johannes Gutenberg Univ Mainz, Inst Anorgan Chem & Analyt Chem, D-55128 Mainz, Germany. US Geol Survey, Flagstaff, AZ 86001 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Space Sci Inst, Boulder, CO 80301 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. RP Washington Univ, Dept Earth & Planetary Sci, Campus Box 1169,1 Brookings Dr, St Louis, MO 63130 USA. EM alianw@levee.wustl.edu RI Hurowitz, Joel/A-8862-2008; Schroder, Christian/B-3870-2009 OI Schroder, Christian/0000-0002-7935-6039 NR 54 TC 90 Z9 92 U1 1 U2 13 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 FEB 21 PY 2006 VL 111 IS E2 AR E02S17 DI 10.1029/2005JE002513 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 021FA UT WOS:000235967900001 ER PT J AU Farassat, F Myers, MK AF Farassat, F Myers, MK TI Further comments on the paper by Zinoviev and Bies, "On acoustic radiation by a rigid object in a fluid flow" SO JOURNAL OF SOUND AND VIBRATION LA English DT Editorial Material ID NOISE; SOUND AB In this note, in response to the previous note by Zinoviev and Bies [Author's Reply to: F. Farassat, Comments on the paper by Zinoviev and Bies "On acoustic radiation by a rigid object in a fluid flow", Journal of Sound and Vibration 281 (2005) 1224-1237], the present authors briefly discuss the assumptions used in the acoustic analogy and its intended applications. It is pointed out that the scattering problems discussed by Zinoviev and Bies do not fall within the intended applications of the Ffowcs Williams-Hawkings (FW-H) equation. However, the FW-H equation can be used to derive an integral equation for finding scattered pressure fields. We derive this integral equation and show the validity of the equation for some of the examples of Zinoviev and Bies. We respond to the other issues brought up by these authors in their notes. We believe that Zinoviev and Bies have misinterpreted the acoustic analogy and have not applied the Curle formula and the FW-H equation correctly. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Langley Res Ctr, Aeroacoust Branch, Hampton, VA 23681 USA. George Washington Univ, Dept Mech & Aerosp Engn, Washington, DC 20052 USA. RP Farassat, F (reprint author), NASA, Langley Res Ctr, Aeroacoust Branch, Hampton, VA 23681 USA. EM feri.farassat@nasa.gov NR 31 TC 1 Z9 1 U1 1 U2 3 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 FEB 21 PY 2006 VL 290 IS 1-2 BP 538 EP 547 DI 10.1016/j.jsv.2005.07.045 PG 10 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 004CP UT WOS:000234729900030 ER PT J AU Mueller, CH Theofylaktos, N Miranda, FA Johnson, AT Pinto, NJ AF Mueller, CH Theofylaktos, N Miranda, FA Johnson, AT Pinto, NJ TI Demonstration of logic AND device using a split-gate pentacene field effect transistor SO THIN SOLID FILMS LA English DT Article DE pentacene; transistor; split-gate; logic; AND gate ID THIN-FILM TRANSISTORS AB We report on the fabrication and performance of pentacene-based split-gate field effect transistors (FETs) on doped Si/SiO2 substrates. Several transistors with split gate structures were fabricated and demonstrated AND logic functionality. The transistor's 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 transistor was conductive (ON), while any other combination of gate voltages rendered the transistor highly resistive (OFF). A significant advantage of this device is that AND logic devices with multiple inputs can be built using a single pentacene channel with multiple gates. The p-type carrier mobility of charge within the pentacene active layer of these transistors was about 10(-5) cm(2)/V-s. We attribute the low value of mobility primarily to the sharp contours of the pentacene film between the drain and the source contacts and to defects in the pentacene film. The average charge density was 1.4 x 10(12) holes/cm(2). Despite low mobility, the devices operated at lower drain-source (V-DS) and gate-source (V-GS) voltages as compared with previously reported pentacene based FETs. (c) 2005 Elsevier B.V. All rights reserved. C1 Analex Corp, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Univ Puerto Rico, Dept Phys & Elect, Humacao, PR 00791 USA. RP Mueller, CH (reprint author), Analex Corp, Cleveland, OH 44135 USA. EM carl.mueller@grc.nasa.gov NR 17 TC 6 Z9 6 U1 1 U2 2 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 FEB 21 PY 2006 VL 496 IS 2 BP 494 EP 499 DI 10.1016/j.tsf.2005.08.276 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 995SR UT WOS:000234124700050 ER PT J AU Peng, C Le, HQ Yang, RQ Hill, CJ AF Peng, C Le, HQ Yang, RQ Hill, CJ TI Multiwavelength discrimination and measurements of a two-gas mixture by use of a broadly tunable mid-infrared semiconductor laser SO APPLIED OPTICS LA English DT Article ID QUANTUM-CASCADE LASER; PHOTOACOUSTIC-SPECTROSCOPY; SPECTROMETER AB Spectroscopic detection of gases can be achieved by measuring a few species-specific absorption lines, requiring very accurate wavelength control. Alternatively, it can be achieved by using many wavelengths spread over a wide range; each wavelength need not be optimal spectroscopically, but all collectively form a unique fingerprint for the species of interest. Statistical regression can be used to quantify their concentrations. An experimental evaluation of this concept involved using a 3.1 mu m broadly tunable Sb-based mid-IR laser to discriminate and measure mixtures of acetylene and water vapor with absorption spectral overlaps. As many as 30 wavelengths from similar to 3200 to similar to 3280 cm(-1) were used to measure 5 X 5 combinations of the two-gas concentration. Statistical analysis of the results validates the concept. Each gas concentration was consistently and reliably measured without any problem of interference from the other. In addition, the method was sufficiently sensitivite to detect unusual discrepancies by use of statistical analysis. Optimization of the system's detection capability and its receiver-operating characteristics is demonstrated. The results suggest that the statistical multiwave-length broadband approach to detection of gas mixture can be a highly effective alternative to species-specific single-line spectroscopy. (c) 2006 Optical Society of America. C1 Univ Houston, Photon Device & Syst Lab, Dept Elect & Comp Engn, Houston, TX 77204 USA. Protea Corp, Sugar Land, TX 77496 USA. Texas Ctr Superconduct & Adv Mat, Sugar Land, TX 77496 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Peng, C (reprint author), Univ Houston, Photon Device & Syst Lab, Dept Elect & Comp Engn, Houston, TX 77204 USA. EM pengchuan@yahoo.com NR 24 TC 0 Z9 1 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 FEB 20 PY 2006 VL 45 IS 6 BP 1275 EP 1287 DI 10.1364/AO.45.001275 PG 13 WC Optics SC Optics GA 016NX UT WOS:000235628000026 PM 16523793 ER PT J AU Schneiderman, JF Delsing, P Shaw, MD Bozler, HM Echternach, PM AF Schneiderman, JF Delsing, P Shaw, MD Bozler, HM Echternach, PM TI Characterization of a differential radio-frequency single-electron transistor SO APPLIED PHYSICS LETTERS LA English DT Article ID SMALL TUNNEL-JUNCTIONS; CHARGE NOISE AB We have fabricated and characterized an electrometer that couples two parallel single-electron transistors (SETs) to a single radio-frequency (RF) tank circuit for use as a differential RF-SET. We demonstrate operation of this device in summing, differential, and single-SET operation modes, and use it to measure a Coulomb staircase from a differential single Cooper-pair box. In differential mode, the device acts to screen out correlated input signals while being sensitive to anticorrelated signals. (c) 2006 American Institute of Physics. C1 Univ So Calif, Dept Phys & Astron, Los Angeles, CA 90089 USA. Chalmers Univ Technol, S-41296 Gothenburg, Sweden. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Schneiderman, JF (reprint author), Univ So Calif, Dept Phys & Astron, Los Angeles, CA 90089 USA. EM pierre.m.echternach@jpl.nasa.gov RI Delsing, Per/F-7288-2010; Schneiderman, Justin/D-4508-2013 OI Delsing, Per/0000-0002-1222-3506; Schneiderman, Justin/0000-0002-4441-2360 NR 11 TC 8 Z9 8 U1 0 U2 2 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 FEB 20 PY 2006 VL 88 IS 8 AR 083506 DI 10.1063/1.2179145 PG 3 WC Physics, Applied SC Physics GA 015LQ UT WOS:000235553300087 ER PT J AU Yamada, T AF Yamada, T TI Equivalent circuit model for carbon nanotube Schottky barrier: Influence of neutral polarized gas molecules SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-EFFECT TRANSISTORS; OXYGEN-ADSORPTION; SINGLE; GRAPHITE; DIPOLES; SURFACE AB An equivalent circuit model is proposed for the Schottky barrier at the junction between a metallic electrode and a semiconducting carbon nanotube (NT). We have applied the model to a gold-NT junction under the presence of neutral polarized NH3 molecules, and have shown that visible Schottky barrier modulation is possible for the gas densities as low as 3x10(13) cm(-2), which is quite feasible experimentally. (c) 2006 American Institute of Physics. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP NASA, Ames Res Ctr, M-S 229-1, Moffett Field, CA 94035 USA. EM tyamada@mail.arc.nasa.gov RI Yamada, Toshishige/E-7834-2012 OI Yamada, Toshishige/0000-0001-7145-9212 NR 26 TC 31 Z9 31 U1 1 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 FEB 20 PY 2006 VL 88 IS 8 AR 083106 DI 10.1063/1.2177356 PG 3 WC Physics, Applied SC Physics GA 015LQ UT WOS:000235553300064 ER PT J AU Beckmann, V Gehrels, N Shrader, CR Soldi, S AF Beckmann, V Gehrels, N Shrader, CR Soldi, S TI The first INTEGRAL AGN catalog SO ASTROPHYSICAL JOURNAL LA English DT Article DE catalogs; galaxies : active; galaxies : Seyfert; gamma rays : observations; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; X-RAY ASTRONOMY; SPECTRAL ENERGY-DISTRIBUTIONS; LUMINOUS SEYFERT-1 GALAXY; XMM-NEWTON OBSERVATION; INSTRUMENT DESCRIPTION; BEPPOSAX OBSERVATIONS; SYNTHESIS MODELS; AVERAGE SPECTRA; EMISSION AB We present the first INTEGRAL AGN catalog, based on observations performed from launch of the mission in 2002 October until 2004 January. The catalog includes 42 AGNs, of which 10 are Seyfert 1, 17 are Seyfert 2, and 9 are intermediate Seyfert 1.5. The fraction of blazars is rather small, with five detected objects, and only one galaxy cluster and no starburst galaxies have been detected so far. A complete subset consists of 32 AGNs with a significance limit of 7 sigma in the INTEGRAL ISGRI 20-40 keV data. Although the sample is not flux limited, the distribution of sources shows a ratio of obscured to unobscured AGNs of 1.5-2.0, consistent with luminosity-dependent unified models for AGNs. Only four Compton-thick AGNs are found in the sample. Based on the INTEGRAL data presented here, the Seyfert 2 spectra are slightly harder (Gamma = 1.95 +/- 0: 01) than Seyfert 1.5 (Gamma = 2.10 +/- 0.02) and Seyfert 1 (Gamma = 2.11 +/- 0: 05). C1 NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. INTEGRAL Sci Data Ctr, CH-1290 Versoix, Switzerland. Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Dept Phys, Baltimore, MD 21250 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Observ Geneva, CH-1290 Sauverny, Switzerland. RP NASA, Goddard Space Flight Ctr, Explorat Universe Div, Code 661, Greenbelt, MD 20771 USA. EM beckmann@milkyway.gsfc.nasa.gov RI Gehrels, Neil/D-2971-2012 NR 69 TC 75 Z9 75 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 FEB 20 PY 2006 VL 638 IS 2 BP 642 EP 652 DI 10.1086/499034 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700007 ER PT J AU Bolton, AS Burles, S Koopmans, LVE Treu, T Moustakas, LA AF Bolton, AS Burles, S Koopmans, LVE Treu, T Moustakas, LA TI The Sloan Lens ACS Survey. I. A large spectroscopically selected sample of massive 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; COLD DARK-MATTER; OPTICAL EINSTEIN RING; NORTH MULTIOBJECT SPECTROGRAPH; GRAVITATIONAL LENS; ELLIPTIC GALAXIES; COSMOLOGICAL PARAMETERS; FUNDAMENTAL PLANE; TARGET SELECTION; BARYONIC INFALL AB The Sloan Lens ACS (SLACS) Survey is an efficient Hubble Space Telescope (HST) Snapshot imaging survey for new galaxy-scale strong gravitational lenses. The targeted lens candidates are selected spectroscopically from the Sloan Digital Sky Survey (SDSS) database of galaxy spectra for having multiple nebular emission lines at a redshift significantly higher than that of the SDSS target galaxy. The SLACS survey is optimized to detect bright early-type lens galaxies with faint lensed sources in order to increase the sample of known gravitational lenses suitable for detailed lensing, photometric, and dynamical modeling. In this paper, the first in a series on the current results of our HST Cycle 13 imaging survey, we present a catalog of 19 newly discovered gravitational lenses, along with nine other observed candidate systems that are either possible lenses, nonlenses, or nondetections. The survey efficiency is thus >= 68%. We also present Gemini 8 m and Magellan 6.5 m integral-field spectroscopic data for nine of the SLACS targets, which further support the lensing interpretation. A new method for the effective subtraction of foreground galaxy images to reveal faint background features is presented. We show that the SLACS lens galaxies have colors and ellipticities typical of the spectroscopic parent sample from which they are drawn (SDSS luminous red galaxies and quiescent MAIN sample galaxies), but are somewhat brighter and more centrally concentrated. Several explanations for the latter bias are suggested. The SLACS survey provides the first statistically significant and homogeneously selected sample of bright early-type lens galaxies, furnishing a powerful probe of the structure of early-type galaxies within the half-light radius. The high confirmation rate of lenses in the SLACS survey suggests consideration of spectroscopic lens discovery as an explicit science goal of future spectroscopic galaxy surveys. C1 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. Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93101 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP MIT, Dept Phys, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM bolton@alum.mit.edu; burles@mit.edu; koopmans@astro.rug.nl; tt@physics.ucsb.edu; leonidas@jpl.nasa.gov OI Moustakas, Leonidas/0000-0003-3030-2360 NR 79 TC 227 Z9 227 U1 2 U2 10 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 FEB 20 PY 2006 VL 638 IS 2 BP 703 EP 724 DI 10.1086/498884 PN 1 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700012 ER PT J AU Spoon, HWW Tielens, AGGM Armus, L Sloan, GC Sargent, B Cami, J Charmandaris, V Houck, JR Soifer, BT AF Spoon, HWW Tielens, AGGM Armus, L Sloan, GC Sargent, B Cami, J Charmandaris, V Houck, JR Soifer, BT TI The detection of crystalline silicates in ultraluminous infrared galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry; dust, extinction; galaxies : ISM; infrared : galaxies; infrared : ISM; ISM : evolution ID SPITZER-SPACE-TELESCOPE; SPECTROGRAPH IRS; INTERSTELLAR-MEDIUM; SPECTROSCOPY; DUST; SPECTRA; STARS; ABSORPTION; DEPENDENCE; MINERALOGY AB Silicates are an important component of interstellar dust, and the structure of these grains (amorphous or crystalline) is sensitive to the local physical conditions. We have studied the infrared spectra of a sample of ultraluminous infrared galaxies (ULIRGs). Here we report the discovery of weak, narrow absorption features at 11, 16, 19, 23, and 28 mu m, characteristic of crystalline silicates, superimposed on the broad absorption bands at 10 and 18 mu m due to amorphous silicates in a subset of this sample. These features betray the presence of forsterite (Mg2SiO4), the magnesiumrich end member of the olivines. Previously, crystalline silicates have only been observed in circumstellar environments. The derived fraction of forsterite to amorphous silicates is typically 0.1 in these ULIRGs. This is much larger than the upper limit for this ratio in the interstellar medium of the MilkyWay, 0.01. These results suggest that the timescale for injection of crystalline silicates into the ISM is short in a merger-driven starburst environment (e.g., as compared to the total time to dissipate the gas), pointing toward massive stars as a prominent source of crystalline silicates. Furthermore, amorphization due to cosmic rays, which is thought to be of prime importance for the local ISM, lags in vigorous starburst environments. C1 Cornell Univ, Astron Dept, Ithaca, NY 14853 USA. SRON Natl Inst Space Res, NL-9700 AV Groningen, Netherlands. Kepteyn Inst, NL-9700 AV Groningen, Netherlands. CALTECH, Pasadena, CA 91125 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NASA Ames Res Ctr, GR-71003 Iraklion, Greece. Univ Crete, Dept Phys, GR-71003 Iraklion, Greece. Observ Paris, F-75014 Paris, France. RP Spoon, HWW (reprint author), Cornell Univ, Astron Dept, Ithaca, NY 14853 USA. RI Charmandaris, Vassilis/A-7196-2008 OI Charmandaris, Vassilis/0000-0002-2688-1956 NR 40 TC 80 Z9 82 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 FEB 20 PY 2006 VL 638 IS 2 BP 759 EP 765 DI 10.1086/498566 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700016 ER PT J AU Vaughan, S Goad, MR Beardmore, AP O'Brien, PT Osborne, JP Page, KL Barthelmy, SD Burrows, DN Campana, S Cannizzo, JK Capalbi, M Chincarini, G Cummings, JR Cusumano, G Giommi, P Godet, O Hill, JE Kobayashi, S Kumar, P La Parola, V Levan, A Mangano, V Meszaros, P Moretti, A Morris, DC Nousek, JA Pagani, C Palmer, DM Racusin, JL Romano, P Tagliaferri, G Zhang, B Gehrels, N AF Vaughan, S Goad, MR Beardmore, AP O'Brien, PT Osborne, JP Page, KL Barthelmy, SD Burrows, DN Campana, S Cannizzo, JK Capalbi, M Chincarini, G Cummings, JR Cusumano, G Giommi, P Godet, O Hill, JE Kobayashi, S Kumar, P La Parola, V Levan, A Mangano, V Meszaros, P Moretti, A Morris, DC Nousek, JA Pagani, C Palmer, DM Racusin, JL Romano, P Tagliaferri, G Zhang, B Gehrels, N TI Swift observations of the X-ray-bright GRB 050315 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; X-rays : individual (GRB 050315) ID ALERT TELESCOPE BAT; BURST AFTERGLOWS; MIDEX MISSION; EMISSION; ENERGETICS; INJECTION; DISCOVERY; SPECTRA AB This paper discusses Swift observations of the mu-ray burst GRB 050315 (z 1: 949) from 80 s to 10 days after the onset of the burst. The X-ray light curve displayed a steep early decay (t(-5)) for similar to 200 s and several breaks. However, both the prompt hard X-ray/gamma-ray emission ( observed by the BAT) and the first similar to 300 s of X-ray emission ( observed by the XRT) can be explained by exponential decays, with similar decay constants. Extrapolating the BAT light curve into the XRT band suggests that the rapidly decaying, early X- ray emission was simply a continuation of the fading prompt emission; this strong similarity between the prompt gamma-ray and early X- ray emission may be related to the simple temporal and spectral character of this X- ray-rich GRB. The prompt ( BAT) spectrum was steep down to similar to 15 keV and appeared to continue through the XRT bandpass, implying a low peak energy, inconsistent with the Amati relation. Following the initial steep decline, the X- ray afterglow did not fade for similar to 1.2 x 10(4) s, after which time it decayed with a temporal index of alpha approximate to 0.7, followed by a second break at similar to 2.5 x 10(5) s to a slope of alpha similar to 2. The apparent "plateau'' in the X- ray light curve, after the early rapid decay, makes this one of the most extreme examples of the steep-flat-steep X- ray light curves revealed by Swift. If the second afterglow break is identified with a jet break, then the jet opening angle was theta(0) similar to 5 degrees, implying E gamma greater than or similar to 10(50) ergs. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. INAF, Osservatorio Astron Brera, I-23807 Merate, Italy. Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Baltimore, MD 21250 USA. ASI Sci Data Ctr, I-00044 Frascati, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. CNR, Washington, DC 20418 USA. INAF, Ist Astrofis Spaziale & Fis Cosm, Sez Palermo, I-90146 Palermo, Italy. Univ Space Res Assoc, Columbia, MD 21044 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. RI Gehrels, Neil/D-2971-2012; Barthelmy, Scott/D-2943-2012; Lujan Center, LANL/G-4896-2012; Racusin, Judith/D-2935-2012; OI Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; La Parola, Valentina/0000-0002-8087-6488; Tagliaferri, Gianpiero/0000-0003-0121-0723 NR 55 TC 120 Z9 121 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 FEB 20 PY 2006 VL 638 IS 2 BP 920 EP 929 DI 10.1086/499069 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700029 ER PT J AU Zavlin, VE AF Zavlin, VE TI XMM-Newton observations of four millisecond pulsars SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (PSR J0034-0534,PSR J0437-4715, PSR J1024-0719, PSR J2124-3358); stars : neutron; X-rays : stars ID X-RAY-EMISSION; RADIATION PAIR FRONTS; POLAR CAPS; J0437-4715; ULTRAVIOLET; CHANDRA; ASCA AB I present an analysis of the XMM-Newton observations of four millisecond pulsars, J0437 - 4715, J2124 - 3358, J1024 - 0719, and J0034 - 0534. The new data provide strong evidence of thermal emission in the X-ray flux detected from the first three objects. This thermal component is best interpreted as radiation from pulsar polar caps covered with a nonmagnetic hydrogen atmosphere. A nonthermal power-law component, dominating at energies E greater than or similar to 3 keV, can also be present in the detected X-ray emission. For PSR J0437 - 4715, the timing analysis reveals that the shape and pulsed fraction of the pulsar light curves are energy dependent. This, together with the results obtained from the phase-resolved spectroscopy, supports the two-component ( thermal plus nonthermal) interpretation of the pulsar's X-ray radiation. Highly significant pulsations have been found in the X-ray flux of PSRs J2124 - 3358 and J1024 - 0719. For PSR J0034 - 0534, a possible X-ray counterpart of the radio pulsar has been suggested. The inferred properties of the detected thermal emission are compared with predictions of radio pulsar models. C1 NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35805 USA. RP Zavlin, VE (reprint author), NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Mail Code SD50, Huntsville, AL 35805 USA. EM vyacheslav.zavlin@msfc.nasa.gov NR 31 TC 47 Z9 47 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 FEB 20 PY 2006 VL 638 IS 2 BP 951 EP 962 DI 10.1086/449308 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700033 ER PT J AU Smith, DM Heindl, WA Markwardt, CB Swank, JH Negueruela, I Harrison, TE Huss, L AF Smith, DM Heindl, WA Markwardt, CB Swank, JH Negueruela, I Harrison, TE Huss, L TI XTE J1739-302 as a supergiant fast X-ray transient SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : neutron; supergiants; X-rays : binaries; X-rays : individual (XTE J1739-302) ID GALACTIC-CENTER REGION; INTEGRAL OBSERVATIONS; CYGNUS X-1; ASCA; DISCOVERY; PULSAR AB XTE J1739-302 is a transient X-ray source with unusually short outbursts, lasting on the order of hours. Here we give a summary of X-ray observations we have made of this object in outburst with the Rossi X-Ray Timing Explorer (RXTE) and at a low level of activity with the Chandra X-Ray Observatory, as well as observations made by other groups. Visible and infrared spectroscopy of the mass donor of XTE J1739-302 are presented in a companion paper. The X-ray spectrum is hard both at low levels and in outburst, but somewhat variable, and there is strong variability in the absorption column from one outburst to another. Although no pulsation has been observed, the outburst data from multiple observatories show a characteristic timescale for variability on the order of 1500 - 2000 s. The Chandra localization (R: A: 17(h)39(m)11(s): s 58, decl. = 30 degrees 20'37"6, J2000.0) shows that despite being located less than 2 degrees from the Galactic center and highly absorbed, XTE J1739 similar to 302 is actually a foreground object with a bright optical counterpart. The combination of a very short outburst timescale and a supergiant companion is shared with several other recently discovered systems, forming a class we designate as supergiant fast X-ray transients (SFXTs). Three persistently bright X-ray binaries with similar supergiant companions have also produced extremely short, bright outbursts: Cyg X-1, Vela X-1, and 1E 1145.1-6141. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Alicante, E-03080 Alicante, Spain. New Mexico State Univ, Dept Astron, Dept 4500, Las Cruces, NM 88003 USA. Calif State Univ Hayward, Hayward, CA 94542 USA. RP Smith, DM (reprint author), Univ Calif Santa Cruz, Dept Phys, 1156 High St, Santa Cruz, CA 95064 USA. RI Swank, Jean/F-2693-2012; Negueruela, Ignacio/L-5483-2014 OI Negueruela, Ignacio/0000-0003-1952-3680 NR 44 TC 65 Z9 65 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 FEB 20 PY 2006 VL 638 IS 2 BP 974 EP 981 DI 10.1086/498936 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700036 ER PT J AU Lynch, DK Woodward, CE Geballe, TR Russell, RW Rudy, RJ Venturini, CC Schwarz, GJ Gehrz, RD Smith, N Lyke, JE Bus, SJ Sitko, ML Harrison, TE Fisher, S Eyres, SP Evans, A Shore, SN Starrfield, S Bode, MF Greenhouse, MA Hauschildt, PH Truran, JW Williams, RE Perry, RB Zamanov, R O'Brien, TJ AF Lynch, DK Woodward, CE Geballe, TR Russell, RW Rudy, RJ Venturini, CC Schwarz, GJ Gehrz, RD Smith, N Lyke, JE Bus, SJ Sitko, ML Harrison, TE Fisher, S Eyres, SP Evans, A Shore, SN Starrfield, S Bode, MF Greenhouse, MA Hauschildt, PH Truran, JW Williams, RE Perry, RB Zamanov, R O'Brien, TJ TI Early infrared spectral development of V1187 scorpii (Nova Scorpii 2004 No. 2) SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; novae, cataclysmic variables; stars : individual (V1187 Scorpii) ID SPITZER-SPACE-TELESCOPE; IRRADIANCE CALIBRATION; ELEMENTAL ABUNDANCES; ULTRAVIOLET EVOLUTION; MICRON SPECTROSCOPY; MODEL ATMOSPHERES; HERCULIS 1991; SPECTROPHOTOMETRY; SPECTROGRAPH; PHOTOMETRY AB We report on an unprecedented infrared time series of spectra of V1187 Sco, a very fast ONeMg nova. The observations covered a 56 day period ( 2004 August 6 - September 30) starting 2 days after the nova's peak brightness. Time evolution of the spectra revealed changing line strengths and profiles on timescales of less than a day to weeks as the nova evolved from early postmaximum to early coronal phases. When our ground-based optical and Spitzer Space Telescope data were combined, the wavelength coverage of 0.38-36 mu m allowed an accurate spectral energy distribution to be derived when it was about 6 weeks after outburst. Developing double structure in the He I lines showed them changing from narrow to broad in only a few days. Using the O I lines in combination with the optical spectra, we derived a reddening of E( B - V) 1: 56 +/- 0: 08 and a distance of 4: 9 +/- 0: 5 kpc. Modeling of the ejected material strongly suggested that it was geometrically thick with Delta R/R = 0.8-0.9 ( more of a wind than a shell) and a low filling factor of order a few percent. The line shapes were consistent with a cylindrical jet, bipolar, or spherical Hubble flow expansion with a maximum speed of about - 3000 km s(-1). The central peak appeared to be more associated with the spherical component, while the two peaks ( especially in H beta) suggested a ring with either a lower velocity component or with its axis inclined to the line of sight. C1 Aerosp Corp, Los Angeles, CA 90009 USA. Univ Minnesota, Dept Astron, Minneapolis, MN 55455 USA. Gemini Observ, Hilo, HI 96720 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. WM Keck Observ, Kamuela, HI 96743 USA. Univ Hawaii, Astron Inst, Hilo, HI 96720 USA. Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. New Mexico State Univ, Dept Astron, Dept 4500, Las Cruces, NM 88003 USA. Univ Cent Lancashire, Dept Phys Astron & Math, Preston PR1 2HE, Lancs, England. Univ Keele, Dept Phys, Keele ST5 5BG, Staffs, England. Univ Pisa, Dipartimento Fis Enrico Fermi, I-56127 Pisa, Italy. Ist Nazl Fis Nucl, Sez Pisa, I-56127 Pisa, Italy. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Hamburger Sternwarte, D-21029 Hamburg, Germany. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. RP Aerosp Corp, Mail Stop 2-266,POB 92957, Los Angeles, CA 90009 USA. EM david.k.lynch@aero.org NR 62 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 EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2006 VL 638 IS 2 BP 987 EP 1003 DI 10.1086/498883 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700038 ER PT J AU Hines, DC Backman, DE Bouwman, J Hillenbrand, LA Carpenter, JM Meyer, MR Kim, JS Silverstone, MD Rodmann, J Wolf, S Mamajek, EE Brooke, TY Padgett, DL Henning, T Moro-Martin, A Stobie, E Gordon, KD Morrison, JE Muzerolle, J Su, KYL AF Hines, DC Backman, DE Bouwman, J Hillenbrand, LA Carpenter, JM Meyer, MR Kim, JS Silverstone, MD Rodmann, J Wolf, S Mamajek, EE Brooke, TY Padgett, DL Henning, T Moro-Martin, A Stobie, E Gordon, KD Morrison, JE Muzerolle, J Su, KYL TI The formation and evolution of planetary systems (FEPS): Discovery of an unusual debris system associated with HD 12039 SO ASTROPHYSICAL JOURNAL LA English DT Review DE circumstellar matter; infrared : stars; planetary systems : protoplanetary disks; stars : individual (HD 12039) ID SPITZER-SPACE-TELESCOPE; INFRARED ARRAY CAMERA; TW-HYDRAE ASSOCIATION; MAIN-SEQUENCE STARS; SOLAR-TYPE STARS; MULTIBAND IMAGING PHOTOMETER; HF-W CHRONOMETRY; HD 98800; CIRCUMSTELLAR DISKS; VEGA PHENOMENON AB We report the discovery of a debris system associated with the similar to 30 Myr old G3/5V star HD 12039 using Spitzer Space Telescope observations from 3.6-160 mu m. An observed infrared excess (L-IR/L-* = 1 x 10(-4)) above the expected photosphere for lambda greater than or similar to 14 mu m is fit by thermally emitting material with a color temperature of T similar to 110 K, warmer than the majority of debris disks identified to date around Sun-like stars. The object is not detected at 70 mu m with a 3 sigma upper limit 6 times the expected photospheric flux. The spectrum of the infrared excess can be explained by warm, optically thin material comprised of blackbody-like grains of size greater than or similar to 7 mu m that reside in a belt orbiting the star at 4-6 AU. An alternate model dominated by smaller grains, near the blowout size a similar to 0.5 mu m, located at 30-40 AU is also possible but requires the dust to have been produced recently, since such small grains will be expelled from the system by radiation pressure in approximately a few times 10(2) yr. C1 Space Sci Inst, Boulder, CO 80301 USA. NASA, SOFIA, Moffett Field, CA 94035 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08540 USA. RP Space Sci Inst, 4750 Walnut St,Suite 205, Boulder, CO 80301 USA. OI Su, Kate/0000-0002-3532-5580 NR 106 TC 48 Z9 48 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 FEB 20 PY 2006 VL 638 IS 2 BP 1070 EP 1079 DI 10.1086/498929 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700045 ER PT J AU Bemporad, A Poletto, G Suess, ST Ko, YK Schwadron, NA Elliott, HA Raymond, JC AF Bemporad, A Poletto, G Suess, ST Ko, YK Schwadron, NA Elliott, HA Raymond, JC TI Current sheet evolution in the aftermath of a CME event SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : coronal mass ejections (CMEs); Sun : UV radiation ID CORONAL MASS EJECTIONS; ELEMENTAL ABUNDANCES; ACTIVE-REGION; SOLAR-FLARE; RECONNECTION; STREAMERS; PLASMA; SPECTROMETER; TEMPERATURE; DIAGNOSTICS AB We report on SOHO UVCS observations of the coronal restructuring following a coronal mass ejection (CME) on 2002 November 26, at the time of a SOHO-Ulysses quadrature campaign. Starting about 1.5 hr after a CME in the northwest quadrant, UVCS began taking spectra at 1.7 R-circle dot, covering emission from both cool and hot plasma. Observations continued, with occasional gaps, for more than 2 days. Emission in the 974.8 angstrom line of [Fe (XVIII)], indicating temperatures above 6 x 10(6) K, was observed throughout the campaign in a spatially limited location. Comparison with EIT images shows the [Fe (XVIII)] emission to overlie a growing post-flare loop system formed in the aftermath of the CME. The emission most likely originates in a current sheet overlying the arcade. Analysis of the [Fe (XVIII)] emission allows us to infer the evolution of physical parameters in the current sheet over the entire span of our observations: in particular, we give the temperature versus time in the current sheet and estimate its density. At the time of the quadrature, Ulysses was directly above the location of the CME and intercepted the ejecta. High ionization state Fe was detected by the Ulysses SWICS throughout the magnetic cloud associated with the CME, although its rapid temporal variation suggests bursty, rather than smooth, reconnection in the coronal current sheet. The SOHO-Ulysses data set provided us with the unique opportunity of analyzing a current sheet structure from its lowest coronal levels out to its in situ properties. Both the remote and in situ observations are compared with predictions of theoretical CME models. C1 Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. Osserv Astrofis Arcetri, INAF, I-50125 Florence, Italy. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. SW Res Inst, San Antonio, TX 78238 USA. RP Univ Florence, Dipartimento Astron & Sci Spazio, Largo Enrico Fermi 5, I-50125 Florence, Italy. EM bemporad@arcetri.astro.it; poletto@arcetri.astro.it OI Bemporad, Alessandro/0000-0001-5796-5653 NR 39 TC 56 Z9 60 U1 1 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 FEB 20 PY 2006 VL 638 IS 2 BP 1110 EP 1128 DI 10.1086/497529 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700049 ER PT J AU Phillips, KJH Dubau, J Sylwester, J Sylwester, B AF Phillips, KJH Dubau, J Sylwester, J Sylwester, B TI Si (XII) X-ray satellite lines in solar flare spectra SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : identification; Sun : flares; Sun : X-rays, gamma rays ID LI-LIKE IONS; INNER-SHELL; EMISSION MEASURES; SPECTROMETER; EXCITATION; PLASMAS; TEMPERATURES; EXPRESSIONS; ABUNDANCES; RHESSI AB The temperature dependence of the Si XII n 3 and 4 dielectronic satellite line features at 5.82 and 5.56 angstrom, respectively, near the Si XIII 1s(2) -1s3p and 1s(2) -1s4p lines (5.681 and 5.405 angstrom), is calculated using atomic data presented here. The resulting theoretical spectra are compared with solar flare spectra observed by the RESIK spectrometer on the CORONAS-F spacecraft. The satellites, like the more familiar n = 2 satellites near the Si XIII 1s(2)-1s2p lines, are formed mostly by dielectronic recombination, but unlike the n = 2 satellites, are unblended. The implications for similar satellite lines in flare Fe spectra are discussed. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Paris 11, LIXAM, F-91405 Orsay, France. Observ Paris, LUTH, F-92190 Meudon, France. Polish Acad Sci, Space Res Ctr, PL-51622 Wroclaw, Poland. RP Phillips, KJH (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM kennethjhphillips@yahoo.com NR 26 TC 19 Z9 19 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 FEB 20 PY 2006 VL 638 IS 2 BP 1154 EP 1161 DI 10.1086/499118 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RA UT WOS:000235425700052 ER PT J AU Gordon, KD Bailin, J Engelbracht, CW Rieke, GH Misselt, KA Latter, WB Young, ET Ashby, MLN Barmby, P Gibson, BK Hines, DC Hinz, J Krause, O Levine, DA Marleau, FR Noriega-Crespo, A Stolovy, S Thilker, DA Werner, MW AF Gordon, KD Bailin, J Engelbracht, CW Rieke, GH Misselt, KA Latter, WB Young, ET Ashby, MLN Barmby, P Gibson, BK Hines, DC Hinz, J Krause, O Levine, DA Marleau, FR Noriega-Crespo, A Stolovy, S Thilker, DA Werner, MW TI Spitzer MIPS infrared imaging of M31: Further evidence for a spiral-ring composite structure SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (M31, M32, NGC 205); galaxies : ISM; galaxies : spiral ID HUBBLE-SPACE-TELESCOPE; NEUTRAL HYDROGEN; COSMOLOGICAL SIMULATIONS; ANDROMEDA GALAXY; LOCAL GROUP; BULGE; DISK; CODE; EMISSION; M-31 AB New images of M31 at 24, 70, and 160 mm taken with the Multiband Imaging Photometer for Spitzer (MIPS) reveal the morphology of the dust in this galaxy. This morphology is well represented by a composite of two logarithmic spiral arms and a circular ring (radius similar to 10 kpc) of star formation offset from the nucleus. The two spiral arms appear to start at the ends of a bar in the nuclear region and extend beyond the star-forming ring. As has been found in previous work, the spiral arms are not continuous, but composed of spiral segments. The star-forming ring is very circular except for a region near M32 where it splits. The lack of well-defined spiral arms and the prominence of the nearly circular ring suggest that M31 has been distorted by interactions with its satellite galaxies. Using new dynamical simulations of M31 interacting with M32 and NGC 205, we find that, qualitatively, such interactions can produce an offset, split ring like that seen in the MIPS images. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Swinburne Univ Technol, Ctr Astrophys & Supercomp, Hawthorn, Vic 3122, Australia. CALTECH, NASA, Herschel Sci Ctr, Pasadena, CA 91125 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Cent Lancashire, Ctr Astrophys, Preston PR1 2HE, Lancs, England. Space Sci Inst, Boulder, CO 80301 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Johns Hopkins Univ, Ctr Astrophys Sci, Baltimore, MD 21218 USA. Jet Propuls Lab, Pasadena, CA 91109 USA. RP Gordon, KD (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM kgordon@as.arizona.edu RI Gibson, Brad/M-3592-2015; Barmby, Pauline/I-7194-2016 OI Gibson, Brad/0000-0003-4446-3130; Barmby, Pauline/0000-0003-2767-0090 NR 53 TC 102 Z9 102 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 FEB 20 PY 2006 VL 638 IS 2 BP L87 EP L92 DI 10.1086/501046 PN 2 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RC UT WOS:000235425900010 ER PT J AU Milligan, RO Gallagher, PT Mathioudakis, M Bloomfield, DS Keenan, FP Schwartz, RA AF Milligan, RO Gallagher, PT Mathioudakis, M Bloomfield, DS Keenan, FP Schwartz, RA TI RHESSI and SOHO CDS observations of explosive chromospheric evaporation 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; SOLAR-FLARE; NONTHERMAL ELECTRONS; EXTREME-ULTRAVIOLET; ENERGY CUTOFFS; SPECTRA; MISSION AB Simultaneous observations of explosive chromospheric evaporation are presented using data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) and the Coronal Diagnostic Spectrometer (CDS) on board the Solar and Heliospheric Observatory. For the first time, cospatial imaging and spectroscopy have been used to observe explosive evaporation within a hard X-ray emitting region. RHESSI X-ray images and spectra were used to determine the flux of nonthermal electrons accelerated during the impulsive phase of an M2.2 flare. When we assumed a thick-target model, the injected electron spectrum was found to have a spectral index of similar to 7.3, a low-energy cutoff of similar to 20 keV, and a resulting flux of >= 4 x10(10) ergs cm(-2) s(-1). The dynamic response of the atmosphere was determined using CDS spectra; we found a mean upflow velocity of 230 +/- 38 km s(-1) in Fe (XIX) (592.23 angstrom) and associated downflows of 36 +/- 16 and 43 +/- 22 km s(-1) at chromospheric and transition region temperatures, respectively, relative to an averaged quiet- Sun spectra. The errors represent a 1 j dispersion. The properties of the accelerated electron spectrum and the corresponding evaporative velocities were found to be consistent with the predictions of theory. C1 Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Dublin Trinity Coll, Sch Phys, Dublin 2, Ireland. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Milligan, RO (reprint author), Queens Univ Belfast, Dept Phys & Astron, Univ Rd, Belfast BT7 1NN, Antrim, North Ireland. EM r.milligan@qub.ac.uk RI Bloomfield, Shaun/G-5809-2011; Gallagher, Peter/C-7717-2011 OI Bloomfield, Shaun/0000-0002-4183-9895; Gallagher, Peter/0000-0001-9745-0400 NR 23 TC 66 Z9 67 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 FEB 20 PY 2006 VL 638 IS 2 BP L117 EP L120 DI 10.1086/500555 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013RC UT WOS:000235425900017 ER PT J AU Fuselier, SA Claflin, ES Mende, SB Carlson, CW Moore, TE AF Fuselier, SA Claflin, ES Mende, SB Carlson, CW Moore, TE TI Combined in situ and remote sensing of ionospheric ion outflow SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CONIC DISTRIBUTIONS; DE-1 ALTITUDES AB Images of charge-exchanged neutrals from ion outflow during a period of substorm recovery are supported by auroral oval images and simultaneous in situ ion outflow measurements. From these combined remote sensing and in situ measurements, the ion outflow is shown to consist of ion conics. The energy of these conics likely increases from < 10 eV at 0.7 R-E to > 10 eV above this altitude. These first global images of the instantaneous outflow show that outflow occurs over nearly the entire dayside auroral oval at high latitudes, including the cusp. The broad local time extent of the outflow is observed for similar to 2.5 hours. Outflow on the nightside may be weaker than on the dayside and/or may have different energyaltitude dependence. C1 Lockheed Martin Adv Technol Ctr, Palo Alto, CA 94304 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fuselier, SA (reprint author), Lockheed Martin Adv Technol Ctr, Palo Alto, CA 94304 USA. RI Moore, Thomas/D-4675-2012 OI Moore, Thomas/0000-0002-3150-1137 NR 14 TC 4 Z9 4 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 FEB 18 PY 2006 VL 33 IS 4 AR L04103 DI 10.1029/2005GL024055 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 017ED UT WOS:000235676000001 ER PT J AU Smith, GL Szewczyk, ZP Rutan, DA Lee, RB AF Smith, GL Szewczyk, ZP Rutan, DA Lee, RB TI Comparison of measurements from satellite radiation budget instruments SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIANT ENERGY SYSTEM; STABILITY ANALYSES; ERB EXPERIMENT; EARTH; CERES; SCANNER; CLOUDS; TERRA; VALIDATION; DATASET AB [ 1] Successive radiometers have been flown on spacecraft for measurement of the radiation budget of the Earth and to date have provided data sets which overlap in time over a 25-year period. Together these data sets cover two cycles of any decadal oscillation and are useful for climate research. However, before multiple data sets can be used, it is necessary first to establish precisions and relative biases of the data sets. Although these instruments were all calibrated with great care, inevitably there are differences between the instruments. Also, instruments change while in orbit due to degradation of optical elements and changes of the detectors. A number of studies have compared measurements between pairs of radiometers in order to establish these differences. In this paper we compile these results and by use of a bar chart demonstrate the traceability of calibration of satellite radiation budget instruments over these two decades. Using this compilation the differences are computed for any two instruments listed. The instruments considered here include the ERBE scanning and nonscanning radiometers, ScaRaB I and II, and the CERES instruments aboard the TRMM, Terra, and Aqua spacecraft. These results are a prerequisite to use of multiple data sets for long-term studies of climate process. The largest biases are between the ERBS scanning and nonscanning radiometers, which at the ``top of the atmosphere'' differ by 5.4 W m(-2) for shortwave fluxes and by 5.8 W m(-2) for daytime longwave fluxes. The standard deviations of the biases, which define how well the data sets can be connected, are less than 1 W m(-2) for longwave and between 1 and 2 W m(-2) for shortwave fluxes. C1 Natl Inst Aerosp, Hampton, VA 23681 USA. Sci Applicat Int Corp, Hampton, VA 23681 USA. Analyt Serv & Mat Inc, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. RP Smith, GL (reprint author), Natl Inst Aerosp, Hampton, VA 23681 USA. EM g.l.smith@larc.nasa.gov NR 32 TC 14 Z9 14 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 FEB 17 PY 2006 VL 111 IS D4 AR D04101 DI 10.1029/2005JD006307 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 017EI UT WOS:000235676500001 ER PT J AU Yizengaw, E Moldwin, MB Komjathy, A Mannucci, AJ AF Yizengaw, E Moldwin, MB Komjathy, A Mannucci, AJ TI Unusual topside ionospheric density response to the November 2003 superstorm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID DYNAMO ELECTRIC-FIELDS; SEVERE MAGNETIC STORM; DISTURBANCE DYNAMO; SOUTHERN-HEMISPHERE; GEOMAGNETIC STORMS; THERMOSPHERE; PENETRATION AB [1] We use observations from a variety of different ground- and space-based instruments, including ionosonde, ground- and space-based Global Positioning System (GPS) receivers, magnetometers, and solar wind data from the Advanced Composition Explorer ( ACE), to examine the response of the ionospheric F2-layer height during the November 2003 superstorm. We found that the topside ionosphere responded unusually to the 20 November 2003 severe storm compared to behavior observed in a number of previous storms. While ground- based GPS receivers observed a large enhancement in dayside TEC, the low-Earth orbiting ( similar to 400 km) CHAMP satellite did not show any sign of dayside TEC enhancement. The real-time vertical density profiles, constructed from ground- based GPS TEC using a tomographic reconstruction technique, clearly revealed that the ionospheric F2-layer peak height had been depressed down to lower altitudes. Ionospheric F-layer peak height (hmF2) from the nearby ionosonde stations over Europe also showed that the dayside F2-layer peak height was below 350 km, which is below the orbiting height of CHAMP. The vertical E x B drift ( estimated from ground- based magnetometer equatorial electrojet delta H) showed strong dayside downward drifts, which may be due to the ionospheric disturbance dynamo electric field produced by the large amount of energy dissipation into high-latitude regions. This storm demonstrates that data from LEO satellites varies widely among different superstorms. C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. Jet Propuls Lab, Pasadena, CA USA. RP Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. EM ekassie@igpp.ucla.edu RI Mannucci, Anthony/A-1349-2007; Moldwin, Mark/F-8785-2011; Yizengaw, Endawoke/I-3471-2015 OI Mannucci, Anthony/0000-0003-2391-8490; Moldwin, Mark/0000-0003-0954-1770; Yizengaw, Endawoke/0000-0001-5772-3355 NR 29 TC 32 Z9 32 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD FEB 17 PY 2006 VL 111 IS A2 AR A02308 DI 10.1029/2005JA011433 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 017EU UT WOS:000235677700002 ER PT J AU Showalter, MR Lissauer, JJ AF Showalter, MR Lissauer, JJ TI The second ring-moon system of Uranus: Discovery and dynamics SO SCIENCE LA English DT Article ID SATURNS F-RING; HUBBLE-SPACE-TELESCOPE; SATELLITES; PHOTOMETRY; ORBITS; MODEL AB Deep exposures of Uranus taken with the Hubble Space Telescope reveal two small moons and two faint rings. All of them orbit outside of Uranus's previously known (main) ring system but are interior to the large, classical moons. The outer new moon, U XXVI Mab, orbits at roughly twice the radius of the main rings and shares its orbit with a dust ring. The second moon, U XXVII Cupid, orbits just interior to the satellite Belinda. A second ring falls between the orbits of Portia and Rosalind, in a region with no known source bodies. Collectively, these constitute a densely packed, rapidly varying, and possibly unstable dynamical system. C1 SETI Inst, Mountain View, CA 94043 USA. NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. RP Showalter, MR (reprint author), SETI Inst, 515 N Whisman Rd, Mountain View, CA 94043 USA. EM mshowalter@seti.org NR 21 TC 36 Z9 36 U1 0 U2 0 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 FEB 17 PY 2006 VL 311 IS 5763 BP 973 EP 977 DI 10.1126/science.1122882 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 014CS UT WOS:000235456900037 PM 16373533 ER PT J AU Rignot, E Kanagaratnam, P AF Rignot, E Kanagaratnam, P TI Changes in the velocity structure of the Greenland ice sheet SO SCIENCE LA English DT Article ID SATELLITE RADAR INTERFEROMETRY; JAKOBSHAVN ISBRAE; GLACIER; ACCELERATION; DISCHARGE; FLOW AB Using satellite radar interferometry observations of Greenland, we detected widespread glacier acceleration below 66 degrees north between 1996 and 2000, which rapidly expanded to 70 degrees north in 2005. Accelerated ice discharge in the west and particularly in the east doubled the ice sheet mass deficit in the last decade from 90 to 220 cubic kilometers per year. As more glaciers accelerate farther north, the contribution of Greenland to sea-level rise will continue to increase. C1 Univ Kansas, Ctr Remote Sensing Ice Sheets, Lawrence, KS 66045 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Rignot, E (reprint author), Univ Kansas, Ctr Remote Sensing Ice Sheets, Lawrence, KS 66045 USA. EM eric.rignot@jpl.nasa.gov; pannir@ku.edu RI Rignot, Eric/A-4560-2014 OI Rignot, Eric/0000-0002-3366-0481 NR 23 TC 669 Z9 693 U1 18 U2 129 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 FEB 17 PY 2006 VL 311 IS 5763 BP 986 EP 990 DI 10.1126/science.1121381 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 014CS UT WOS:000235456900041 PM 16484490 ER PT J AU Manney, GL Santee, ML Froidevaux, L Hoppel, K Livesey, NJ Waters, JW AF Manney, GL Santee, ML Froidevaux, L Hoppel, K Livesey, NJ Waters, JW TI EOS MLS observations of ozone loss in the 2004-2005 Arctic winter SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LIMB SOUNDER MEASUREMENTS AB Earth Observing System Microwave Limb Sounder O(3) and N(2)O are used to examine transport and chemical O(3) loss in the unusually cold 2004 - 2005 Arctic winter. The vortex was dynamically active, with episodic mixing events throughout the winter; descent was the dominant transport process only through late January. Before the onset of lower stratospheric chemical loss, O(3) was higher near the vortex edge than in the vortex core, causing different effects of mixing depending on the vortex region and time, either masking or mimicking chemical loss. O(3) loss ceased by 10 March because of an early final warming. Rough estimates suggest maximum vortex- averaged O(3) loss of 1.2-1.5 ppmv between 450 and 500 K, with up to similar to 2 ppmv loss in the outer vortex near 500 K. Despite record cold, chemical O(3) loss was less in 2004 - 2005 than in previous cold Arctic winters. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. USN, Res Lab, Washington, DC 20375 USA. New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. RP Manney, GL (reprint author), CALTECH, Jet Propuls Lab, 4800 Oak Grove Dr,Mail Stop 183-701, Pasadena, CA 91109 USA. EM manney@mls.jpl.nasa.gov NR 11 TC 63 Z9 63 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 FEB 16 PY 2006 VL 33 IS 4 AR L04802 DI 10.1029/2005GL024494 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 017EB UT WOS:000235675800002 ER PT J AU Herkenhoff, KE Squyres, SW Anderson, R Archinal, BA Arvidson, RE Barrett, JM Becker, KJ Bell, JF Budney, C Cabrol, NA Chapman, MG Cook, D Ehlmann, BL Farmer, J Franklin, B Gaddis, LR Galuszka, DM Garcia, PA Hare, TM Howington-Kraus, E Johnson, JR Johnson, S Kinch, K Kirk, RL Lee, EM Leff, C Lemmon, M Madsen, MB Maki, JN Mullins, KF Redding, BL Richter, L Rosiek, MR Sims, MH Soderblom, LA Spanovich, N Springer, R Sucharski, RM Sucharski, T Sullivan, R Torson, JM Yen, A AF Herkenhoff, KE Squyres, SW Anderson, R Archinal, BA Arvidson, RE Barrett, JM Becker, KJ Bell, JF Budney, C Cabrol, NA Chapman, MG Cook, D Ehlmann, BL Farmer, J Franklin, B Gaddis, LR Galuszka, DM Garcia, PA Hare, TM Howington-Kraus, E Johnson, JR Johnson, S Kinch, K Kirk, RL Lee, EM Leff, C Lemmon, M Madsen, MB Maki, JN Mullins, KF Redding, BL Richter, L Rosiek, MR Sims, MH Soderblom, LA Spanovich, N Springer, R Sucharski, RM Sucharski, T Sullivan, R Torson, JM Yen, A TI Overview of the Microscopic Imager Investigation during Spirit's first 450 sols in Gusev crater SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MARS; ROVER; ROCKS AB The Microscopic Imager (MI) on the Mars Exploration Rover Spirit has returned images of Mars with higher resolution than any previous camera system, allowing detailed petrographic and sedimentological studies of the rocks and soils at the Gusev landing site. Designed to simulate a geologist's hand lens, the MI is mounted on Spirit's instrument arm and can resolve objects 0.1 mm in size or larger. This paper provides an overview of MI operations, data calibration, processing, and analysis of MI data returned during the first 450 sols (Mars days) of the Spirit landed mission. The primary goal of this paper is to facilitate further analyses of MI data by summarizing the methods used to acquire and process the data, the radiometric and geometric accuracy of MI data products, and the availability of archival products. In addition, scientific results of the MI investigation are summarized. MI observations show that poorly sorted soils are common in Gusev crater, although aeolian bedforms have well-sorted coarse sand grains on their surfaces. Abraded surfaces of plains rocks show igneous textures, light-toned veins or fracture-filling minerals, and discrete coatings. The rocks in the Columbia Hills have a wide variety of granular textures, consistent with volcaniclastic or impact origins. Case hardening and submillimeter veins observed in the rocks as well as soil crusts and cemented clods imply episodic subsurface aqueous fluid movement, which has altered multiple geologic units in the Columbia Hills. The MI also monitored Spirit's solar panels and the magnets on the rover's deck. C1 US Geol Survey, Astrogeol Team, Flagstaff, AZ 86001 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. Univ Oxford, Dept Geog & Environm, Environm Change Inst, Oxford OX1 3QY, England. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. Danish Space Res Inst, Ctr Planetary Sci, Copenhagen, Denmark. Univ Copenhagen, Niels Bohr Inst Astron Phys & Geophys, DK-2100 Copenhagen, Denmark. DLR, Inst Raumsimulat, D-51170 Cologne, Germany. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. RP US Geol Survey, Astrogeol Team, 2255 N Gemini Dr, Flagstaff, AZ 86001 USA. EM kherkenhoff@usgs.gov RI Lemmon, Mark/E-9983-2010; Madsen, Morten/D-2082-2011; Kinch, Kjartan/C-5742-2015; Johnson, Jeffrey/F-3972-2015; OI Lemmon, Mark/0000-0002-4504-5136; Madsen, Morten/0000-0001-8909-5111; Kinch, Kjartan/0000-0002-4629-8880; Hare, Trent/0000-0001-8842-389X NR 50 TC 39 Z9 39 U1 1 U2 6 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 FEB 16 PY 2006 VL 111 IS E2 AR E02S04 DI 10.1029/2005JE002574 PG 30 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 017EK UT WOS:000235676700001 ER PT J AU Mushinzimana, E Munga, S Minakawa, N Li, L Feng, CC Bian, L Kitron, U Schmidt, C Beck, L Zhou, GF Githeko, AK Yan, GY AF Mushinzimana, E Munga, S Minakawa, N Li, L Feng, CC Bian, L Kitron, U Schmidt, C Beck, L Zhou, GF Githeko, AK Yan, GY TI Landscape determinants and remote sensing of anopheline mosquito larval habitats in the western Kenya highlands SO MALARIA JOURNAL LA English DT Article ID TREATED BED NETS; MALARIA TRANSMISSION; INSECTICIDE RESISTANCE; SPATIAL-DISTRIBUTION; AFRICA; RISK; EPIDEMIOLOGY; CULICIDAE; DIPTERA; EFFICACY AB Background: In the past two decades the east African highlands have experienced several major malaria epidemics. Currently there is a renewed interest in exploring the possibility of anopheline larval control through environmental management or larvicide as an additional means of reducing malaria transmission in Africa. This study examined the landscape determinants of anopheline mosquito larval habitats and usefulness of remote sensing in identifying these habitats in western Kenya highlands. Methods: Panchromatic aerial photos, Ikonos and Landsat Thematic Mapper 7 satellite images were acquired for a study area in Kakamega, western Kenya. Supervised classification of land-use and land-cover and visual identification of aquatic habitats were conducted. Ground survey of all aquatic habitats was conducted in the dry and rainy seasons in 2003. All habitats positive for anopheline larvae were identified. The retrieved data from the remote sensors were compared to the ground results on aquatic habitats and land-use. The probability of finding aquatic habitats and habitats with Anopheles larvae were modelled based on the digital elevation model and land-use types. Results: The misclassification rate of land-cover types was 10.8% based on Ikonos imagery, 22.6% for panchromatic aerial photos and 39.2% for Landsat TM 7 imagery. The Ikonos image identified 40.6% of aquatic habitats, aerial photos identified 10.6%, and Landsate TM 7 image identified 0%. Computer models based on topographic features and land-cover information obtained from the Ikonos image yielded a misclassification rate of 20.3 - 22.7% for aquatic habitats, and 18.1 - 25.1% for anopheline-positive larval habitats. Conclusion: One-metre spatial resolution Ikonos images combined with computer modelling based on topographic land-cover features are useful tools for identification of anopheline larval habitats, and they can be used to assist to malaria vector control in western Kenya highlands. C1 Univ Calif Irvine, Program Publ Hlth, Irvine, CA 92697 USA. Kenya Govt Med Res Ctr, Climate & Human Hlth Res Unit, Ctr Vector Biol & Control Res, Nairobi, Kenya. NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Ctr Hlth Applicat Aerosp Related Technol, Stanford, CA 94305 USA. Univ Illinois, Coll Vet Med, Dept Pathobiol, Urbana, IL 61802 USA. SUNY Buffalo, Dept Geog, Buffalo, NY 14260 USA. SUNY Buffalo, Natl Ctr Geog Informat & Anal, Buffalo, NY 14260 USA. RP Yan, GY (reprint author), Univ Calif Irvine, Program Publ Hlth, Irvine, CA 92697 USA. EM Emushinzimana@kisian.mimcom.net; smunga@kisian.mimcom.net; minakawa@net.nagasaki-u.ac.jp; lli7@buffalo.edu; feng@uwp.edu; lbian@buffalo.edu; ukitron@uiuc.edu; cschmidt@mail.arc.nasa.gov; lback@mail.arc.nasa.gov; gzhou2@buffalo.edu; agitheko@kisian.mimcom.net; guiyuny@uci.edu RI Feng, Chen-Chieh/F-9993-2012 OI Feng, Chen-Chieh/0000-0003-0410-714X FU FIC NIH HHS [D43 TW001505, D43 TW01505]; NIAID NIH HHS [R01 AI 50243] NR 57 TC 70 Z9 73 U1 2 U2 13 PU BIOMED CENTRAL LTD PI LONDON PA MIDDLESEX HOUSE, 34-42 CLEVELAND ST, LONDON W1T 4LB, ENGLAND SN 1475-2875 J9 MALARIA J JI Malar. J. PD FEB 16 PY 2006 VL 5 AR 13 DI 10.1186/1475-2875-5-13 PG 11 WC Infectious Diseases; Parasitology; Tropical Medicine SC Infectious Diseases; Parasitology; Tropical Medicine GA 026YY UT WOS:000236380700001 PM 16480523 ER PT J AU Nourbakhsh, I Sargent, R Wright, A Cramer, K Mcclendon, B Jones, M AF Nourbakhsh, I Sargent, R Wright, A Cramer, K Mcclendon, B Jones, M TI Mapping disaster zones SO NATURE LA English DT Editorial Material C1 Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. NASA Ames, Moffett Field, CA USA. RP Nourbakhsh, I (reprint author), Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. NR 0 TC 37 Z9 39 U1 1 U2 5 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD FEB 16 PY 2006 VL 439 IS 7078 BP 787 EP 788 DI 10.1038/439787a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 012JA UT WOS:000235333600024 PM 16482134 ER PT J AU Ilhan, F Tyson, DS Meador, MA AF Ilhan, F Tyson, DS Meador, MA TI Phenacenes from Diels-Alder trapping of photogenerated o-xylylenols: Phenanthrenes and benzo[e]pyrene bisimide SO ORGANIC LETTERS LA English DT Article ID ELECTRON-TRANSFER; ACCEPTOR MOLECULES; THIN-FILMS; DERIVATIVES; DONOR; BENZOPYRENE; HYDROCARBON; CONVERSION; DIMERS; DYES AB The synthesis of phenanthrene and benzo[e]pyrene bisimides, 1 and 2, was accomplished via the Diels-Alder trapping of sterically congested o-xylylerlols photochemically generated from 3,6-dibenzoyl-o-xylene and 1;4-dibenzoyl-9,10-dihydroanthracene, respectively. Absorption and emission from 2 are red-shifted from 1 and unsubstituted benzo[e]pyrene. The fluorescence quantum yield for 2 is an order of magnitude lower than that of 1 and comparable to that of the parent benzo[e]pyrene. C1 NASA, Glenn Res Ctr, Polymers Branch, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Cleveland, OH 44135 USA. RP Ilhan, F (reprint author), NASA, Glenn Res Ctr, Polymers Branch, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM michael.a.meador@nasa.gov NR 33 TC 7 Z9 8 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1523-7060 J9 ORG LETT JI Org. Lett. PD FEB 16 PY 2006 VL 8 IS 4 BP 577 EP 580 DI 10.1021/ol052711d PG 4 WC Chemistry, Organic SC Chemistry GA 015EN UT WOS:000235534800008 PM 16468715 ER PT J AU Ho, CS Banerjee, S Koel, BE Duchemin, OB Polk, JE AF Ho, CS Banerjee, S Koel, BE Duchemin, OB Polk, JE TI Desorption of chemisorbed Carbon on Mo(100) by noble gas ion sputtering: Validation of ground test measurements of ion engine lifetimes SO APPLIED SURFACE SCIENCE LA English DT Article DE desorption; carbon; Mo(100); sputtering; ions; Ne+; Ar+; Xe+; low-energy ion scattering (LEIS); desorption cross section; ion-engine lifetimes ID IMPACT DESORPTION; SURFACE-LAYERS; MOLYBDENUM; SCATTERING; SULFUR; LEED AB We report desorption cross section measurements for one monolayer of chemisorbed carbon on a Mo(100) surface induced by sputtering with noble gas ions (Ne+, Ar+, Xe+) at different incident angles, ion energies, and substrate temperatures. Desorption cross sections were determined by using low-energy ion scattering (LEIS) to monitor the increase of the signal from the Mo substrate. A monolayer of p(1 x 1) carbon adatoms on the Mo(100) surface was created by dosing ethylene (C2H4) to the substrate at 800 K, and characterized by Auger electron spectroscopy (AES) and low energy electron diffraction (LEED). We find that the carbon desorption cross section increases with increasing mass and energy of the impinging ions, and there is a maximum value for the desorption cross section at an incident angle for the ions of 30 degrees from the surface plane. The desorption cross section also increases up to a substrate temperature of 300 degrees C. Values for the carbon desorption cross section for carbon adatoms on Mo(100) by 400-eV Xe+ ion sputtering are about 2 x 10(-15) cm(2), which is one order of magnitude higher than those for bulk carbon samples. This information is particularly important for evaluation of ion-engine lifetimes from ground-test measurements in which contaminant carbon is deposited on Mo accelerator grids, potentially altering the sputtering rate of the Mo. Our measurements show that monolayer amounts of carbon on Mo have desorption cross sections that are two orders of magnitude higher than estimates of what would be required to reduce the Mo erosion rate, and thus ground-test measurements can be used with confidence to predict ion-engine wear in space, from this perspective. (c) 2006 Elsevier B.V. All rights reserved. C1 Univ So Calif, Dept Chem, Los Angeles, CA 90089 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Koel, BE (reprint author), Lehigh Univ, CAMN, Dept Chem, Sinclair Lab 305C, 7 Asa Dr, Bethlehem, PA 18015 USA. EM brk205@lehigh.edu RI Koel, Bruce/H-3857-2013 OI Koel, Bruce/0000-0002-0032-4991 NR 18 TC 5 Z9 5 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD FEB 15 PY 2006 VL 252 IS 8 BP 2657 EP 2664 DI 10.1016/j.apsusc.2005.03.216 PG 8 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 017VQ UT WOS:000235721800002 ER PT J AU Roy, S Zorman, C Mehregany, M DeAnna, R Deeb, C AF Roy, S Zorman, C Mehregany, M DeAnna, R Deeb, C TI The mechanical properties of polycrystalline 3C-SiC films grown on polysilicon substrates by atmospheric pressure chemical-vapor deposition SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THERMAL-EXPANSION; RESIDUAL-STRESS; SILICON-CARBIDE; ELASTIC-MODULUS; DEFORMATION AB This paper presents the results of a study to determine Young's modulus, residual stress, and burst strength of polycrystalline 3C silicon carbide (poly-SiC) films grown on as-deposited and annealed polysilicon substrate layers. The biaxial modulus and residual stress were determined for bulk micromachined poly-SiC diaphragms using an interferometric load-deflection measurement apparatus. The load-deflection data were analyzed using a least-squares fitting technique to extract the biaxial modulus and residual stress values, and Young's modulus was calculated assuming a Poisson ratio of 0.15. Poly-SiC films comprised of equiaxed grains exhibited Young's modulus values ranging from 452 to 494 GPa, while columnar films with a high degree of (110) texture exhibited Young's modulus values between 340 and 357 GPa. The residual stress for these films did not exhibit a discernable relationship with microstructure; however, the values exhibited a general dependence on growth temperature. Poly-SiC films grown at 1280 degrees C had residual stress values ranging from 401 to 486 MPa, while a film grown at 1160 degrees C had a residual stress value of 113 MPa. Burst strength was determined using a combination of finite element analysis and burst pressure measurements of the suspended diaphragms. Poly-SiC films grown at 1280 degrees C exhibited an average burst strength value of 1718 MPa, while the poly-SiC film grown at 1160 degrees C had an average burst strength value of 1321 MPa. (c) 2006 American Institute of Physics. C1 Case Western Reserve Univ, Dept Elect Engn & Comp Sci, Cleveland, OH 44106 USA. NASA, Glenn Res Ctr Lewis Field, USA, Res Lab, Cleveland, OH 44135 USA. Case Western Reserve Univ, Dept Mat Sci & Engn, Cleveland, OH 44106 USA. RP Roy, S (reprint author), Case Western Reserve Univ, Dept Elect Engn & Comp Sci, Cleveland, OH 44106 USA. EM christian.zorman@case.edu OI Zorman, Christian/0000-0001-9773-9351 NR 28 TC 24 Z9 25 U1 1 U2 11 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 FEB 15 PY 2006 VL 99 IS 4 AR 044108 DI 10.1063/1.2169875 PG 13 WC Physics, Applied SC Physics GA 016ZF UT WOS:000235663100044 ER PT J AU Wilber, AC Smith, GL Gupta, SK Stackhouse, PW AF Wilber, AC Smith, GL Gupta, SK Stackhouse, PW TI Annual cycles of surface shortwave radiative fluxes SO JOURNAL OF CLIMATE LA English DT Article ID 10-YEAR DATA SET; INTERANNUAL VARIATIONS; SEASONAL-VARIATION; SATELLITE DATA; CLIMATE; BUDGET; CLOUDS AB The annual cycles of surface shortwave flux are investigated using the 8-yr dataset of the surface radiation budget (SRB) components for the period July 1983-June 1991. These components include the downward, upward, and net shortwave radiant fluxes at the earth's surface. The seasonal cycles are quantified in terms of principal components that describe the temporal variations and empirical orthogonal functions (EOFs) that describe the spatial patterns. The major part of the variation is simply due to the variation of the insolation at the top of the atmosphere, especially for the first term, which describes 92.4% of the variance for the downward shortwave flux. However, for the second term, which describes 4.1% of the variance, the effect of clouds is quite important and the effect of clouds dominates the third term, which describes 2.4% of the variance. To a large degree the second and third terms are due to the response of clouds to the annual cycle of solar forcing. For net shortwave flux at the surface, similar variances are described by each term. The regional values of the EOFs are related to climate classes, thereby defining the range of annual cycles of shortwave radiation for each climate class. C1 NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. Analyt Serv & Mat Inc, Hampton, VA 23666 USA. Natl Inst Aerosp, Hampton, VA USA. RP NASA, Langley Res Ctr, Div Atmospher Sci, MS 936, Hampton, VA 23681 USA. EM a.c.wilber@larc.nasa.gov RI wilber, anne/F-6270-2011 NR 16 TC 10 Z9 10 U1 0 U2 1 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 FEB 15 PY 2006 VL 19 IS 4 BP 535 EP 547 DI 10.1175/JCLI3625.1 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 021HF UT WOS:000235973600003 ER PT J AU Meltzner, AJ Sieh, K Abrams, M Agnew, DC Hudnut, KW Avouac, JP Natawidjaja, DH AF Meltzner, Aron J. Sieh, Kerry Abrams, Michael Agnew, Duncan C. Hudnut, Kenneth W. Avouac, Jean-Philippe Natawidjaja, Danny H. TI Uplift and subsidence associated with the great Aceh-Andaman earthquake of 2004 SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID GPS MEASUREMENTS; DEFORMATION; MICROATOLLS; SUBDUCTION; TECTONICS; RUPTURE; ARC AB Rupture of the Sunda megathrust on 26 December 2004 produced broad regions of uplift and subsidence. We define the pivot line separating these regions as a first step in defining the lateral extent and the downdip limit of rupture during that great M-w approximate to 9.2 earthquake. In the region of the Andaman and Nicobar islands we rely exclusively on the interpretation of satellite imagery and a tidal model. At the southern limit of the great rupture we rely principally on field measurements of emerged coral microatolls. Uplift extends from the middle of Simeulue Island, Sumatra, at similar to 2.5 degrees N, to Preparis Island, Myanmar (Burma), at similar to 14.9 degrees N. Thus the rupture is similar to 1600 km long. The distance from the pivot line to the trench varies appreciably. The northern and western Andaman Islands rose, whereas the southern and eastern portion of the islands subsided. The Nicobar Islands and the west coast of Aceh province, Sumatra, subsided. Tilt at the southern end of the rupture is steep; the distance from 1.5 m of uplift to the pivot line is just 60 km. Our method of using satellite imagery to recognize changes in elevation relative to sea surface height and of using a tidal model to place quantitative bounds on coseismic uplift or subsidence is a novel approach that can be adapted to other forms of remote sensing and can be applied to other subduction zones in tropical regions. C1 CALTECH, Div Geol & Planetary Sci, Tecton Observ, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. US Geol Survey, Pasadena, CA 91106 USA. Indonesian Inst Sci, Res Ctr Geotechnol, Bandung 40135, Indonesia. RP Meltzner, AJ (reprint author), CALTECH, Div Geol & Planetary Sci, Tecton Observ, Pasadena, CA 91125 USA. EM meltzner@gps.caltech.edu; sieh@gps.caltech.edu RI Meltzner, Aron/A-5585-2009; Hudnut, Kenneth/B-1945-2009; Hudnut, Kenneth/G-5713-2010; Avouac, Jean-Philippe/B-5699-2015; OI Hudnut, Kenneth/0000-0002-3168-4797; Avouac, Jean-Philippe/0000-0002-3060-8442; Agnew, Duncan/0000-0002-2360-7783; Meltzner, Aron/0000-0002-2955-0896 NR 20 TC 107 Z9 108 U1 1 U2 18 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD FEB 15 PY 2006 VL 111 IS B2 AR B02407 DI 10.1029/2005JB003891 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 066AL UT WOS:000239201600002 ER PT J AU Yu, JR Trieu, BC Modlin, EA Singh, UN Kavaya, MJ Chen, SS Bai, YX Petzar, PJ Petros, M AF Yu, JR Trieu, BC Modlin, EA Singh, UN Kavaya, MJ Chen, SS Bai, YX Petzar, PJ Petros, M TI 1 J/pulse Q-switched 2 mu m solid-state laser SO OPTICS LETTERS LA English DT Article ID ENERGIES AB Q-switched output of 1.1 J/pulse at a 2.053 mu m, wavelength has been achieved in a diode-pumped Ho:Tm:LuLF laser with a side-pumped rod configuration in a master-oscillator-power-amplifier (MOPA) architecture. This is the first time to our knowledge that a 2 mu m laser has broken the joule per pulse barrier for Q-switched operation. The total system efficiency reaches 5% and 6.2% for single- and double-pulse operation, respectively. The system produces an excellent 1.4 times transform-limited beam quality. (c) 2006 Optical Society of America. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. SAIC, Hampton, VA 23666 USA. Sci & Technol Corp, Hampton, VA 23666 USA. RP Yu, JR (reprint author), NASA, Langley Res Ctr, Mail Stop 468, Hampton, VA 23681 USA. EM jirong.yu@larc.nasa.gov NR 13 TC 122 Z9 134 U1 4 U2 16 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 FEB 15 PY 2006 VL 31 IS 4 BP 462 EP 464 DI 10.1364/OL.31.000462 PG 3 WC Optics SC Optics GA 012PA UT WOS:000235350000012 PM 16496887 ER PT J AU Burlaga, LF Vinas, AF AF Burlaga, LF Vinas, AF TI Triangle for the entropic index q of non-extensive statistical mechanics observed by Voyager 1 in the distant heliosphere SO PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS LA English DT Article DE non-linear dynamics; non-extensive statistical mechanics; metastable states; mixing; weak chaos; q-triplet; heliospheric magnetic field ID MAGNETIC-FIELD; AU AB Tsallis [Physica A 340 (2004) 1) identified a set of numbers, the "q-triplet" equivalent to {q(stat), q(sen), q(rel)}, for a system described by non-extensive statistical mechanics. The deviation of the q's from Unity is a measure of the departure from thermodynamic equilibrium. We present observations of the q-triplets derived from two sets of daily averages of the magnetic field strength B observed by Voyager 1 in the solar wind near 40 A.U. during 1989 and near 85 A.U. during 2002, respectively. The results for 1989 do not differ significantly from those for 2002. We find q(stat) = 1.75 +/- 0.06, q(stat) = -0.6 +/- 0.2, and q(rel) = 3.8 +/- 0.3. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. RP Burlaga, LF (reprint author), NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Code 612-2, Greenbelt, MD 20771 USA. EM Leonard.F.Burlaga@nasa.gov NR 16 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD FEB 15 PY 2006 VL 361 IS 1 BP 173 EP 179 DI 10.1016/j.physa.2005.06.097 PG 7 WC Physics, Multidisciplinary SC Physics GA 015DX UT WOS:000235533200011 ER PT J AU Min, QL Lin, B AF Min, QL Lin, B TI Remote sensing of evapotranspiration and carbon uptake at Harvard Forest SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE evapotranspiration; carbon uptake; microwave emissivity; vegetation water content ID VEGETATION WATER-CONTENT; SPECTRAL REFLECTANCE; MICROWAVE EMISSION; SOIL-MOISTURE; LIQUID WATER; RADIATION; INDEXES; AREA AB A land surface vegetation index, defined as the difference of microwave land surface emissivity at 19 and 37 GHz, was calculated for a heavily forested area in north central Massachusetts. The microwave emissivity difference vegetation index (EDVI) was estimated from satellite SSM/I measurements at the defined wavelengths and used to estimate land surface turbulent fluxes. Narrowband visible and infrared measurements and broadband solar radiation observations were used in the EDVI retrievals and turbulent flux estimations. The EDVI values represent physical properties of crown vegetation such as vegetation water content of crown canopies. The collocated land surface turbulent and radiative fluxes were empirically linked together by the EDVI values. The EDVI values are statistically sensitive to evapotranspiration fractions (EF) with a correlation coefficient (R) greater than 0.79 under all-sky conditions. For clear skies, EDVI estimates exhibit a stronger relationship with EF than normalized difference vegetation index (NDVI). Furthermore, the products of EDVI and input energy (solar and photosynthetically active radiation) are statistically significantly correlated to evapotranspiration (R=0.95) and CO2 uptake flux (R=0.74), respectively. (C) 2005 Elsevier Inc. All rights reserved. C1 SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12222 USA. NASA, Langley Res Ctr, Radiat & Aerosols Branch, Hampton, VA 23665 USA. RP Min, QL (reprint author), SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12222 USA. EM min@asrc.cestm.albany.edu NR 36 TC 34 Z9 38 U1 1 U2 13 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 FEB 15 PY 2006 VL 100 IS 3 BP 379 EP 387 DI 10.1016/j.rse.2005.10.020 PG 9 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 013PD UT WOS:000235420400009 ER PT J AU Squyres, SW Arvidson, RE Blaney, DL Clark, BC Crumpler, L Farrand, WH Gorevan, S Herkenhoff, KE Hurowitz, J Kusack, A McSween, HY Ming, DW Morris, RV Ruff, SW Wang, A Yen, A AF Squyres, Steven W. Arvidson, Raymond E. Blaney, Diana L. Clark, Benton C. Crumpler, Larry Farrand, William H. Gorevan, Stephen Herkenhoff, Kenneth E. Hurowitz, Joel Kusack, Alastair McSween, Harry Y. Ming, Douglas W. Morris, Richard V. Ruff, Steven W. Wang, Alian Yen, Albert TI Rocks of the Columbia Hills SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MARS EXPLORATION ROVERS; GUSEV CRATER; SPIRIT ROVER; SPECTROMETER; SOILS AB [ 1] The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present. C1 Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Lockheed Martin Corp, Littleton, CO 80127 USA. New Mexico Museum Nat Hist & Sci, Albuquerque, NM 87104 USA. Space Sci Inst, Boulder, CO 80301 USA. Honeybee Robot, New York, NY 10001 USA. US Geol Survey, Flagstaff, AZ 86001 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Univ Tennessee, Dept Earth & Planetary Sci, Knoxville, TN 37996 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. RP Squyres, SW (reprint author), Cornell Univ, Dept Astron, 428 Space Sci Bldg, Ithaca, NY 14853 USA. EM squyres@astrosun.tn.cornell.edu RI Hurowitz, Joel/A-8862-2008 NR 28 TC 108 Z9 109 U1 5 U2 20 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 FEB 14 PY 2006 VL 111 IS E2 AR E02S11 DI 10.1029/2005JE002562 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 066AG UT WOS:000239201100002 ER PT J AU Han, WQ Liu, WT Lin, JL AF Han, WQ Liu, WT Lin, JL TI Impact of atmospheric submonthly oscillations on sea surface temperature of the tropical Indian Ocean SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INTRASEASONAL VARIABILITY; SUMMER MONSOON; MODE; CIRCULATION; CONVECTION; FLUXES AB Impacts of atmospheric intraseasonal oscillations (ISOs) at submonthly periods ( 10 - 30 days) on Indian Ocean sea surface temperature (SST) are studied using satellite observed outgoing long wave radiation, QuikSCAT winds, SST and an ocean general circulation model for the period of 1999 - 2004. The results suggest that submonthly ISOs can cause significant 10 - 30 day SST changes throughout the equatorial basin and northern Bay of Bengal, with an amplitude of as large as 0.5 degrees C and standard deviation of exceeding 0.2 degrees C for a 4-year record. Impact of the submonthly ISO associated with the Indian summer monsoon is separately examined. It is associated with basin-scale SST evolution with distinct spatial structures. The SST variation results mainly from submonthly wind forcing, which causes changes in oceanic processes and surface turbulent heat fluxes. Radiative fluxes can also have large influences in some regions for some ISO events. C1 Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NOAA, Climate Diagnost Ctr, CIRES, Boulder, CO 80305 USA. RP Han, WQ (reprint author), Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. EM whan@enso.colorado.edu NR 25 TC 24 Z9 24 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 FEB 11 PY 2006 VL 33 IS 3 AR L03609 DI 10.1029/2005GL025082 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 012TH UT WOS:000235362100006 ER PT J AU Fergason, RL Christensen, PR Bell, JF Golombek, MP Herkenhoff, KE Kieffer, HH AF Fergason, RL Christensen, PR Bell, JF Golombek, MP Herkenhoff, KE Kieffer, HH TI Physical properties of the Mars Exploration Rover landing sites as inferred from Mini-TES-derived thermal inertia SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID GUSEV CRATER; MERIDIANI-PLANUM; EMISSION SPECTROMETER; SPIRIT ROVER; PARTICLE-SIZE; PARTICULATE MATERIALS; NORTHERN-HEMISPHERE; MICROSCOPIC IMAGER; OPPORTUNITY ROVER; AEOLIAN PROCESSES AB [1] The Miniature Thermal Emission Spectrometer (Mini-TES) on board the two Mars Exploration Rovers provides the first opportunity to observe thermal properties from the Martian surface, relate these properties to orbital data, and perform soil conductivity experiments under Martian conditions. The thermal inertias of soils, bedforms, and rock at each landing site were derived to quantify the physical properties of these features and understand geologic processes occurring at these localities. The thermal inertia for the Gusev plains rock target Bonneville Beacon ( similar to 1200 J m(-2) K-1 s(-1/2)) is consistent with a dense, basaltic rock, but the rocks at the Columbia Hills have a lower thermal inertia ( similar to 620 J m(-2) K-1 s(-1/2)), suggesting that they have a volcaniclasic origin. Bedforms on the floors of craters at both landing sites have thermal inertias of 200 J m(-2) K-1 s(-1/2), consistent with a particle diameter of similar to 160 mu m. This diameter is comparable to the most easily moved grain size in the current atmosphere on Mars, suggesting that these bedforms may have formed under current atmospheric conditions. Along the Meridiani plains, the thermal inertia is lower than that derived from TES and Thermal Emission Imaging System (THEMIS) orbital data. This discrepancy is not well understood. Mini-TES-derived thermal inertias at Gusev along a similar to 2.5 km traverse follow trends in thermal inertia measured from orbit with TES and THEMIS. However, along the traverse, there are variability and mixing of particle sizes that are not resolved in the orbital thermal inertia data due to meter-scale processes that are not identifiable at larger scales. C1 Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. US Geol Survey, Astrogeol Team, Flagstaff, AZ 86001 USA. Celestial Reasonings, Carson City, NV 89703 USA. RP Arizona State Univ, Dept Geol Sci, Box 876305, Tempe, AZ 85287 USA. EM robin.fergason@asu.edu NR 72 TC 67 Z9 67 U1 0 U2 3 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 FEB 11 PY 2006 VL 111 IS E2 AR E02S21 DI 10.1029/2005JE002583 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 012TV UT WOS:000235363800002 ER PT J AU Parkinson, CD Stewart, AIF Wong, AS Yung, YL Ajello, JM AF Parkinson, CD Stewart, AIF Wong, AS Yung, YL Ajello, JM TI Enhanced transport in the polar mesosphere of Jupiter: Evidence from Cassini UVIS helium 584 angstrom airglow SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID LYMAN-ALPHA ALBEDO; IO PLASMA TORUS; UPPER-ATMOSPHERE; HYDROCARBON PHOTOCHEMISTRY; RADIATIVE-TRANSFER; JOVIAN AURORA; LINE-PROFILE; ULTRAVIOLET; HE; DAYGLOW AB [1] The eddy diffusion profile ( K) in the auroral regions of Jupiter is not well determined. However, because of the intense auroral energy input, eddy mixing is expected to be much more effective and may be responsible for the enhancement of heavy hydrocarbon production in the polar region. In this paper, we estimate the increased eddy mixing in the Jovian auroral regions by comparing the Cassini Ultraviolet Imaging Spectrograph (UVIS) observations during the 2000 Jupiter flyby with radiative transfer calculations of the He 584 angstrom airglow intensity. We derive a range for the eddy diffusion coefficients at the homopause (K-h) in the auroral regions to be at least 8 x 10(6) cm(2) s(-1) and possibly greater than 4 x 10(7) cm(2) s(-1). By comparison, equatorial K-h is on the order of 2 x 10(6) cm(2) s(-1). C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, Astrobiol Inst, Pasadena, CA USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. RP Parkinson, CD (reprint author), CALTECH, Div Geol & Planetary Sci, 150-21, Pasadena, CA 91125 USA. EM cdp@gps.caltech.edu NR 37 TC 5 Z9 5 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 FEB 11 PY 2006 VL 111 IS E2 AR E02002 DI 10.1029/2005JE002539 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 012TV UT WOS:000235363800001 ER PT J AU Rodriguez, J Bodaghee, A Kaaret, P Tomsick, JA Kuulkers, E Malaguti, G Petrucci, PO Cabanac, C Chernyakova, M Corbel, S Deluit, S Di Cocco, G Ebisawa, K Goldwurm, A Henri, G Lebrun, F Paizis, A Walter, R Foschini, L AF Rodriguez, J Bodaghee, A Kaaret, P Tomsick, JA Kuulkers, E Malaguti, G Petrucci, PO Cabanac, C Chernyakova, M Corbel, S Deluit, S Di Cocco, G Ebisawa, K Goldwurm, A Henri, G Lebrun, F Paizis, A Walter, R Foschini, L TI INTEGRAL and XMM-Newton observations of the X-ray pulsar IGR J16320-4751/AX J1631.9-4752 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE stars : neutron; pulsars : general; stars : individual : IGR J16320-4751; AX J1631.9-4752; X-rays : binaries ID IGR J16320-4751; EMISSION; DISCOVERY; CHANDRA; ORIGIN; LINES AB We report on observations of the X-ray pulsar IGR J16320-4751 (also known as AX J1631.9-4752) performed simultaneously with International Gamma-Ray Astrophysics Laboratory (INTEGRAL) and XMM-Newton. We refine the source position and identify the most likely infrared counterpart. Our simultaneous coverage allows us to confirm the presence of X-ray pulsations at similar to 1300 s, that we detect above 20 keV with INTEGRAL for the first time. The pulse fraction is consistent with being constant with energy, which is compatible with a model of polar accretion by a pulsar. We study the spectral properties of IGR J16320-4751 during two major periods occurring during the simultaneous coverage with both satellites, namely a flare and a non-flare period. We detect the presence of a narrow 6.4 keV iron line in both periods. The presence of such a feature is typical of supergiant wind accretors such as Vela X-1 or GX 301-2. We inspect the spectral variations with respect to the pulse phase during the non-flare period, and show that the pulse is solely due to variations of the X-ray flux emitted by the source and not due to variations of the spectral parameters. Our results are therefore compatible with the source being a pulsar in a High Mass X-ray Binary. We detect a soft excess appearing in the spectra as a blackbody with a temperature of similar to 0.07 keV. We discuss the origin of the X-ray emission in IGR J16320-4751: while the hard X-rays are likely the result of Compton emission produced in the close vicinity of the pulsar, based on energy argument we suggest that the soft excess is likely the emission by a collisionally energized cloud in which the compact object is embedded. C1 CEA Saclay, DSM, DAPNIA, Serv Astrophys, F-91191 Gif Sur Yvette, France. Univ Paris 07, UMR 7158, AIM, Paris, France. ISDC, CH-1290 Versoix, Switzerland. Observ Geneva, CH-1290 Sauverny, Switzerland. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. ISOC, ESA, ESAC, Madrid 28080, Spain. INAF, IASC, I-40129 Bologna, Italy. Observ Grenoble, Astrophys Lab, F-38041 Grenoble, France. Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 4, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Unite Mixte Rech APC, F-75005 Paris, France. INA, IASF, Sez Milano, I-20133 Milan, Italy. RP Rodriguez, J (reprint author), CEA Saclay, DSM, DAPNIA, Serv Astrophys, F-91191 Gif Sur Yvette, France. EM rodrigue@discovery.saclay.cea.fr RI Foschini, Luigi/H-3833-2012; OI Foschini, Luigi/0000-0001-8678-0324; Malaguti, Giuseppe/0000-0001-9872-3378; Rodriguez, Jerome/0000-0002-4151-4468; Paizis, Adamantia/0000-0001-5067-0377 NR 35 TC 29 Z9 29 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 FEB 11 PY 2006 VL 366 IS 1 BP 274 EP 282 DI 10.1111/j.1365-2966.2005.09855.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 006DW UT WOS:000234876700037 ER PT J AU Villar-Martin, M Sanchez, SF De Breuck, C Peletier, R Vernet, J Rettura, A Seymour, N Humphrey, A Stern, D Alighieri, SD Fosbury, R AF Villar-Martin, M Sanchez, SF De Breuck, C Peletier, R Vernet, J Rettura, A Seymour, N Humphrey, A Stern, D Alighieri, SD Fosbury, R TI VIMOS-VLT and Spitzer observations of a radio galaxy at z=2.5 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; galaxies : evolution; galaxies : individual; MRC 2104-242 ID SPACE-TELESCOPE; DEEP-FIELD; Z-SIMILAR-TO-2.5; SPECTROSCOPY; LUMINOSITY; EVOLUTION; HUBBLE; SAMPLE; IRAC; UV AB We present: (i) a kinematic and morphological study of the giant Ly alpha nebula associated with the radio galaxy MRC 2104-242 (z = 2.49) based on integral field spectroscopic Visible Multiobject Spectrograph (VIMOS) data from the Very Large Telescope (VLT), and (ii) a photometric study of the host ( proto?) galaxy based on Spitzer Space Telescope data. The galaxy appears to be embedded in a giant (greater than or similar to 120 kpc) gas reservoir that surrounds it completely. The kinematic properties of the nebula suggest that it is a rotating structure, which would imply a lower limit to the dynamical mass of similar to 3 x 10(11)M(circle dot). An alternate scenario is that the gas is infalling. Such a process would be able to initiate and sustain significant central starburst activity, although it is likely to contribute with less than 10 per cent of the total stellar mass. The near- to mid-infrared spectral energy distribution of the radio galaxy suggests the existence of a reddened, E( B - V) = 0.4 +/- 0.1, evolved stellar population of age greater than or similar to 1.8 Gyr and mass (5 +/- 2) x 10(11)M(circle dot). The implied formation redshift is z(f) greater than or similar to 6. This stellar mass is similar to the stellar masses found for massive early-type galaxies at z similar to 2 in deep, near- infrared surveys. C1 CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Ctr Astron Hispano Aleman Calar Alto, Almeria, Spain. European So Observ, D-85748 Garching, Germany. Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. Univ Paris 11, F-91405 Orsay, France. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Univ Hertfordshire, Dept Phys Sci, Hatfield AL10 9AB, Herts, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. INAF, Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. ST ECF, D-85748 Garching, Germany. RP Villar-Martin, M (reprint author), CSIC, Inst Astrofis Andalucia, Aptdo 3004, E-18080 Granada, Spain. EM montse@iaa.es RI Peletier, Reynier/B-9633-2012; di Serego Alighieri, Sperello/E-4067-2010; Humphrey, Andrew/M-4118-2013; Villar Martin, Montserrat/C-3126-2017; OI di Serego Alighieri, Sperello/0000-0001-8769-2692; Humphrey, Andrew/0000-0002-0510-2351; Villar Martin, Montserrat/0000-0003-2566-2126; Seymour, Nicholas/0000-0003-3506-5536 NR 29 TC 27 Z9 27 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD FEB 11 PY 2006 VL 366 IS 1 BP L1 EP L5 DI 10.1111/j.1745-3933.2005.00118.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 006DW UT WOS:000234876700001 ER PT J AU Chazelas, B Brachet, F Borde, P Mennesson, B Ollivier, M Absil, O Labeque, A Valette, C Leger, A AF Chazelas, B Brachet, F Borde, P Mennesson, B Ollivier, M Absil, O Labeque, A Valette, C Leger, A TI Instrumental stability requirements for exoplanet detection with a nulling interferometer: variability noise as a central issue SO APPLIED OPTICS LA English DT Article ID EXTRASOLAR PLANETS AB We revisit the nulling interferometer performances that are needed for direct detection and the spectroscopic analysis of exoplanets, e.g., with the DARWIN [European Space Agency-SCI 12 (2000)] or TPF-I [JPL Publ. 05-5, (2005)] missions. Two types of requirement are found, one concerning the mean value of the instrumental nulling function < nl(lambda)> and another regarding its stability. The stress is usually put on the former. It is stringent at short wavelengths but somewhat relaxed at longer wavelengths. The latter, which we call the variability noise condition, does not usually receive enough attention. It is required regardless of telescope size and stellar distance. The results from three nulling experiments performed in laboratories around the world are reported and compared with the requirements. All three exhibit 1/f noise that is incompatible with the performances required by the mission. As pointed out by Lay [Appl. Opt. 43, 6100-6123 (2004)], this stability problem is not fully solved by modulation techniques. Adequate solutions must be found that are likely to include servo systems using the stellar signal itself as a reference and internal metrology with high stability. (c) 2006 Optical Society of America. C1 Univ Paris 11, CNRS, Inst Astrophys Spatiale, F-91405 Orsay, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Liege, Inst Astrophys & Geophys, B-4000 Liege, Belgium. RP Chazelas, B (reprint author), Univ Paris 11, CNRS, Inst Astrophys Spatiale, Batiment 121, F-91405 Orsay, France. EM Alain.Leger@ias.u-psud.fr OI Absil, Olivier/0000-0002-4006-6237 NR 15 TC 18 Z9 18 U1 1 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 FEB 10 PY 2006 VL 45 IS 5 BP 984 EP 992 DI 10.1364/AO.45.000984 PG 9 WC Optics SC Optics GA 013CO UT WOS:000235387400021 PM 16512542 ER PT J AU Corp, LA Middleton, EM McMurtrey, JE Campbell, PKE Butcher, LM AF Corp, LA Middleton, EM McMurtrey, JE Campbell, PKE Butcher, LM TI Fluorescence sensing techniques for vegetation assessment SO APPLIED OPTICS LA English DT Article ID CHLOROPHYLL-A FLUORESCENCE; LASER-INDUCED FLUORESCENCE; IN-FIELD CORN; GREEN PLANTS; REFLECTANCE MEASUREMENTS; NUTRIENT DEFICIENCIES; PHOTOSYNTHETIC RATE; PHOTOSYSTEM-I; EXCITATION; LEAVES AB Active fluorescence (F) sensing systems have long been suggested as a means to identify species composition and determine physiological status of plants. Passive F systems for large-scale remote assessment of vegetation will undoubtedly rely on solar-induced F (SIF), and this information could potentially be obtained from the Fraunhofer line depth (FLD) principle. However, understanding the relationships between the information and knowledge gained from active and passive systems remains to be addressed. Here we present an approach in which actively induced F spectral data are used to simulate and project the magnitude of SIF that can be expected from near-ground observations within selected solar Fraunhofer line regions. Comparisons among vegetative species and nitrogen (N) supply treatments were made with three F approaches: the passive FLD principle applied to telluric oxygen (O-2) bands from field-acquired canopy reflectance spectra, simulated SIF from actively induced laboratory emission spectra of leaves at a series of solar Fraunhofer lines ranging from 422 to 758 nm, and examination of two dual-F excitation algorithms developed from laboratory data. From these analyses we infer that SIF from whole-plant canopies can be simulated by use of laboratory data from active systems on individual leaves and that SIF has application for the large-scale assessment of vegetation. (c) 2006 Optical Society of America. C1 Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. USDA ARS, Hydrol & Remote Sensing Lab, Beltsville, MD 20705 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21250 USA. RP Sci Syst & Applicat Inc, Lanham, MD 20706 USA. EM lcorp@hydrolab.arsusda.gov RI Campbell, Petya/A-9649-2008; Campbell, Petya/G-4931-2013; Campbell, Petya/L-7486-2013 OI Campbell, Petya/0000-0002-0505-4951; Campbell, Petya/0000-0002-0505-4951 NR 41 TC 33 Z9 33 U1 5 U2 13 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 FEB 10 PY 2006 VL 45 IS 5 BP 1023 EP 1033 DI 10.1364/AO.45.001023 PG 11 WC Optics SC Optics GA 013CO UT WOS:000235387400025 PM 16512546 ER PT J AU Kondratko, PT Greenhill, LJ Moran, JM Lovell, JEJ Kuiper, TBH Jauncey, DL Cameron, LB Gomez, JF Garcia-Miro, C Moll, E de Gregorio-Monsalvo, I Jimenez-Bailon, E AF Kondratko, PT Greenhill, LJ Moran, JM Lovell, JEJ Kuiper, TBH Jauncey, DL Cameron, LB Gomez, JF Garcia-Miro, C Moll, E de Gregorio-Monsalvo, I Jimenez-Bailon, E TI Discovery of water maser emission in eight AGNs with 70 m antennas of NASA'S Deep Space Network SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (AM 2158-380 NED02, IC 0184, NGC 0235A, NGC 0613, NGC 3393, NGC 4293, NGC 5495, VII Zw 073); galaxies : Seyfert; ISM : jets and outflows; ISM : molecules; masers ID ACTIVE GALACTIC NUCLEI; DWARF SEYFERT NUCLEI; PARSEC-SCALE JET; H2O MASER; NEARBY GALAXIES; CIRCINUS GALAXY; ACCRETION DISK; BLACK-HOLE; X-RAY; SEARCH AB We report the discovery of water maser emission in eight active galactic nuclei (AGNs) with the 70 m NASA Deep Space Network (DSN) antennas at Tidbinbilla, Australia, and Robledo, Spain. The positions of the newly discovered masers, measured with the VLA, are consistent with the optical positions of the host nuclei to within 1 sigma(0 ''.3 radio and 1 ''.3 optical) and most likely mark the locations of the embedded central engines. The spectra of two sources, NGC 3393 and NGC 5495, display the characteristic spectral signature of emission from an edge-on accretion disk, with orbital velocities of similar to 600 and similar to 400 km s(-1), respectively. In a survey with DSN facilities of 630 AGNs selected from the NASA Extragalactic Database, we have discovered a total of 15 water maser sources. The resulting incidence rate of maser emission among nearby (v(sys) < 7000 km s(-1)) Seyfert 1.8-2.0 and LINER systems is similar to 10% for a typical rms noise level of similar to 14 mJy over 1.3 km s(-1) spectral channels. As a result of this work, the number of nearby AGNs (v(sys) < 7000 km s(-1)) observed with < 20 mJy rms noise has increased from 130 to 449. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Jet Propuls Lab, Pasadena, CA 91109 USA. CSIRO, Australia Telescope Natl Facil, Epping, NSW 2121, Australia. Canberra Deep Space Commun Complex, Paddys Creek, ACT 2609, Australia. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. NASA, INTA, E-28008 Madrid, Spain. INTA, Lab Astrofis Espac & Fis Fundamental, E-28080 Madrid, Spain. RP Kondratko, PT (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM pkondrat@cfa.harvard.edu RI Gomez, Jose Francisco/D-8392-2016; OI Gomez, Jose Francisco/0000-0002-7065-542X; Moran, James/0000-0002-3882-4414 NR 42 TC 40 Z9 41 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 FEB 10 PY 2006 VL 638 IS 1 BP 100 EP 105 DI 10.1086/498641 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100008 ER PT J AU Murphy, EJ Braun, R Helou, G Armus, L Kenney, JDP Gordon, KD Bendo, GJ Dale, DA Walter, F Oosterloo, TA Kennicutt, RC Calzetti, D Cannon, JM Draine, BT Engelbracht, CW Hollenbach, DJ Jarrett, TH Kewley, LJ Leitherer, C Li, A Meyer, MJ Regan, MW Rieke, GH Rieke, MJ Roussel, H Sheth, K Smith, JDT Thornley, MD AF Murphy, EJ Braun, R Helou, G Armus, L Kenney, JDP Gordon, KD Bendo, GJ Dale, DA Walter, F Oosterloo, TA Kennicutt, RC Calzetti, D Cannon, JM Draine, BT Engelbracht, CW Hollenbach, DJ Jarrett, TH Kewley, LJ Leitherer, C Li, A Meyer, MJ Regan, MW Rieke, GH Rieke, MJ Roussel, H Sheth, K Smith, JDT Thornley, MD TI In initial look at the far-infrared-radio correlation within nearby star-forming galaxies using the Spitzer Space Telescope SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; infrared : galaxies; radio continuum : galaxies ID MULTIBAND IMAGING PHOTOMETER; OPTICAL HII-REGIONS; SPIRAL GALAXIES; PANCHROMATIC VIEW; EMISSION; CONTINUUM; LUMINOSITIES; CATALOG; MODEL; SINGS AB We present an initial look at the far-infrared-radio correlation within the star-forming disks of four nearby, nearly face-on galaxies (NGC 2403, NGC 3031, NGC 5194, and NGC 6946). Using Spitzer MIPS imaging, observed as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS), and Westerbork Synthesis Radio Telescope (WSRT) radio continuum data, taken for the WSRT SINGS radio continuum survey, we are able to probe variations in the logarithmic 24 mu m/22 cm (q(24)) and 70 mu m/22 cm (q(70)) surface brightness ratios across each disk at subkiloparsec scales. We find general trends of decreasing q(24) and q(70) with declining surface brightness and with increasing radius. The residual dispersion around the trend of q(24) and q(70) versus surface brightness is smaller than the residual dispersion around the trend of q(24) and q(70) versus radius, on average by similar to 0.1 dex, indicating that the distribution of star formation sites is more important in determining the infrared/radio disk appearance than the exponential profiles of disks. We have also performed preliminary phenomenological modeling of cosmic-ray electron (CR electron) diffusion using an image-smearing technique and find that smoothing the infrared maps improves their correlation with the radio maps. We find that exponential smoothing kernels work marginally better than Gaussian kernels, independent of projection for these nearly face-on galaxies. This result suggests that additional processes besides simple random walk diffusion in three dimensions must affect the evolution of CR electrons. The best-fit smoothing kernels for the two less active star-forming galaxies (NGC 2403 and NGC 3031) have much larger scale lengths than those of the more active star-forming galaxies (NGC 5194 and NGC 6946). This difference may be due to the relative deficit of recent CR electron injection into the interstellar medium for the galaxies that have largely quiescent disks. C1 Yale Univ, Dept Astron, New Haven, CT 06520 USA. ASTRON, NL-7990 AA Dwingeloo, Netherlands. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91101 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Bucknell Univ, Dept Phys, Lewisburg, PA 17837 USA. RP Murphy, EJ (reprint author), Yale Univ, Dept Astron, POB 208101, New Haven, CT 06520 USA. EM murphy@astro.yale.edu OI Draine, Bruce/0000-0002-0846-936X NR 39 TC 61 Z9 61 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 FEB 10 PY 2006 VL 638 IS 1 BP 157 EP 175 DI 10.1086/498636 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100014 ER PT J AU Freyer, T Hensler, G Yorke, HW AF Freyer, T Hensler, G Yorke, HW TI Massive stars and the energy balance of the interstellar medium. II. The 35 M-circle dot star and a solution to the "missing wind problem" SO ASTROPHYSICAL JOURNAL LA English DT Article DE HII regions; hydrodynamics; ISM : bubbles; ISM : individual (S308); ISM : structure; X-rays : individual (S308) ID WOLF-RAYET STARS; RING NEBULA NGC-6888; NGC 6888; SPECTRAL-ANALYSIS; BUBBLES; EVOLUTION; EMISSION; HD-50896; ENVIRONMENT; IMPACT AB We continue our numerical analysis of the morphological and energetic influence of massive stars on their ambient interstellar medium for a 35 M-circle dot star that evolves from the main-sequence through red supergiant and Wolf-Rayet phases, until it ultimately explodes as a supernova. We find that structure formation in the circumstellar gas during the early main-sequence evolution occurs as in the 60 M-circle dot case but is much less pronounced because of the lower mechanical wind luminosity of the star. On the other hand, since the shell-like structure of the H-II region is largely preserved, effects that rely on this symmetry become more important. At the end of the stellar lifetime 1% of the energy released as Lyman continuum radiation and stellar wind has been transferred to the circumstellar gas. From this fraction 10% is kinetic energy of bulk motion, 36% is thermal energy, and the remaining 54% is ionization energy of hydrogen. The sweeping up of the slow red supergiant wind by the fast Wolf-Rayet wind produces remarkable morphological structures and emission signatures, which are compared with existing observations of the Wolf-Rayet bubble S308, whose central star has probably evolved in a manner very similar to our model star. Our model reproduces the correct order of magnitude of observed X-ray luminosity, the temperature of the emitting plasma, and the limb brightening of the intensity profile. This is remarkable, because current analytical and numerical models of Wolf-Rayet bubbles fail to consistently explain these features. A key result is that almost the entire X-ray emission in this stage comes from the shell of red supergiant wind swept up by the shocked Wolf-Rayet wind rather than from the shocked Wolf- Rayet wind itself as hitherto assumed and modeled. This offers a possible solution to what is called the "missing wind problem" of Wolf-Rayet bubbles. C1 Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany. Univ Observ Vienna, Inst Astron, A-1180 Vienna, Austria. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Freyer, T (reprint author), Univ Kiel, Inst Theoret Phys & Astrophys, Olshaussenstr 40, D-24098 Kiel, Germany. EM freyer@astrophysik.uni-kiel.de; hensler@astro.univie.ac.at; Harold.Yorke@jpl.nasa.gov NR 38 TC 80 Z9 80 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 FEB 10 PY 2006 VL 638 IS 1 BP 262 EP 280 DI 10.1086/498734 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100024 ER PT J AU Gudipati, MS Allamandola, LJ AF Gudipati, MS Allamandola, LJ TI Unusual stability of polycyclic aromatic hydrocarbon radical cations in amorphous water ices up to 120 K: Astronomical implications SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; methods : laboratory; molecular processes; radiation mechanisms : nonthermal; ultraviolet : ISM; ultraviolet : solar system ID OUTER SOLAR-SYSTEM; INTERSTELLAR ICE; ULTRAVIOLET-IRRADIATION; EMBEDDED PROTOSTARS; ASTROPHYSICAL ICES; ORGANIC-MOLECULES; FACILE GENERATION; FLASH-PHOTOLYSIS; EXCESS ELECTRONS; MATRIX-ISOLATION AB The PAH radical cation quaterrylene(+) (QTR(+), C40H20) is found to be stable in amorphous water ice up to 120 K. A careful, 30 day, slow warm-up of water ice containing QTR(+) from 20 to 190 K revealed that QTR(+) does not show any sign of reactivity up to 120 K, the temperature at which the phase transition of amorphous to crystalline water ice begins. At higher temperatures the absorption due to the QTR radical cation diminishes rapidly but persists until the water ice itself sublimes around 170 K. From the absence of evidence for the recovery of neutral QTR upon warm-up or reactions with other trapped reaction intermediates in the ice, we infer that QTR(+) reacts with the water ice itself during warm-up above 120 K. Earlier we found that PAH ionization is quantitative in water ice and PAH ionization energy is lowered by up to 2 eV. Some implications of these unusual findings for cosmic ice chemistry and physics are briefly discussed. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Maryland, IPST, College Pk, MD 20742 USA. Univ Cologne, Inst Phys Chem, Cologne, Germany. RP Gudipati, MS (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM gudipati@ipst.umd.edu; louis.j.allamandola@nasa.gov RI Gudipati, Murthy/F-7575-2011 NR 68 TC 24 Z9 24 U1 3 U2 20 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 FEB 10 PY 2006 VL 638 IS 1 BP 286 EP 292 DI 10.1086/498816 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100026 ER PT J AU Enoch, ML Young, KE Glenn, J Evans, NJ Golwala, S Sargent, AI Harvey, P Aguirre, J Goldin, A Haig, D Huard, TL Lange, A Laurent, G Maloney, P Mauskopf, P Rossinot, P Sayers, J AF Enoch, ML Young, KE Glenn, J Evans, NJ Golwala, S Sargent, AI Harvey, P Aguirre, J Goldin, A Haig, D Huard, TL Lange, A Laurent, G Maloney, P Mauskopf, P Rossinot, P Sayers, J TI Bolocam survey for 1.1 mm dust continuum emission in the c2d legacy clouds. I. Perseus SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : clouds; ISM : individual (Perseus); stars : formation ID MASS STAR-FORMATION; PRE-PROTOSTELLAR CORES; BARNARD-1 DARK CLOUD; MOLECULAR CLOUDS; INTERSTELLAR EXTINCTION; INITIAL CONDITIONS; DENSITY STRUCTURE; CARBON-MONOXIDE; CLUSTER IC-348; PROTOSTARS AB We have completed a 1.1 mm continuum survey of 7.5 deg(2) of the Perseus Molecular Cloud using Bolocam at the Caltech Submillimeter Observatory. This represents the largest millimeter or submillimeter continuum map of Perseus to date. Our map covers more than 30,000 3100 (FWHM) resolution elements to a 1 sigma rms of 15 mJy beam(-1). We detect a total of 122 cores above a 5 sigma point-source mass detection limit of 0.18 M-circle dot, assuming a dust temperature of TD = 10 K, 60 of which are new millimeter or submillimeter detections. The 1.1 mm mass function is consistent with a broken power law of slope alpha 1 = 1.3 ( 0.5 M-circle dot < M < 2.5 M-circle dot) and alpha 2 = 2.6 ( M > 2.5 M-circle dot), similar to the local initial mass function slope (alpha(1)=1.6, M < 1M(circle dot); alpha(2) = 2.7M > 1M(circle dot)). No more than 5% of the total cloud mass is contained in discrete 1.1 mm cores, which account for a total mass of 285 M-circle dot. We suggest an extinction threshold for millimeter cores of AV similar to 5 mag, based on our calculation of the probability of finding a 1.1 mm core as a function of AV. Much of the cloud is devoid of compact millimeter emission; despite the significantly greater area covered compared to previous surveys, only 5 - 10 of the newly identified sources lie outside previously observed areas. The two-point correlation function confirms that dense cores in the cloud are highly structured, with significant clustering on scales as large as 2 x 10(5) AU. Our 1.1 mm emission survey reveals considerably denser, more compact material than maps in other column density tracers such as (CO)-C-13 and A(V), although the general morphologies are roughly consistent. These 1.1 mm results, especially when combined with recently acquired c2d Spitzer Legacy data, will provide a census of dense cores and protostars in Perseus and improve our understanding of the earliest stages of star formation in molecular clouds. C1 CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Cardiff Wales, Cardiff, Wales. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Enoch, ML (reprint author), CALTECH, Div Phys Math & Astron, 770 S Wilson Ave, Pasadena, CA 91125 USA. EM menoch@astro.caltech.edu; kaisa@astro.as.utexas.edu; jason.glenn@colorado.edu NR 77 TC 218 Z9 218 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 FEB 10 PY 2006 VL 638 IS 1 BP 293 EP 313 DI 10.1086/498678 PN 1 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100027 ER PT J AU Granot, J Ramirez-Ruiz, E Taylor, GB Eichler, D Lyubarsky, YE Wijers, RAMJ Gaensler, BM Gelfand, JD Kouveliotou, C AF Granot, J Ramirez-Ruiz, E Taylor, GB Eichler, D Lyubarsky, YE Wijers, RAMJ Gaensler, BM Gelfand, JD Kouveliotou, C TI Diagnosing the outflow from the SGR 1806-20 giant flare with radio observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; ISM : bubbles; pulsars : individual (SGR 1806-20); stars : flare; stars : neutron; stars : winds, outflows ID SGR 1806-20; MAGNETAR SGR-1806-20; AFTERGLOW; DISTANCE AB On 2004 December 27, the soft gamma repeater (SGR) 1806-20 emitted the brightest giant flare (GF) ever detected from an SGR. This burst of energy, which resulted in an ( isotropic) energy release similar to 100 times greater than the only two other known SGR GFs, was followed by a very bright, fading radio afterglow. Extensive follow-up radio observations provided a wealth of information with unprecedented astrometric precision, revealing the temporal evolution of the source size, along with densely sampled light curves and spectra. Here we expand on our previous work on this source, by explaining these observations within one self-consistent dynamical model. In this scenario, the early radio emission is due to the outflow ejected during the GF energizing a thin shell surrounding a preexisting cavity, where the observed steep temporal decay of the radio emission seen beginning on day 9 is attributed to the adiabatic cooling of the shocked shell. The shocked ejecta and external shell move outward together, driving a forward shock into the ambient medium, and are eventually decelerated by a reverse shock. As we show in a separate work by Gelfand and coworkers, the radio emission from the shocked external medium naturally peaks when significant deceleration occurs and then decays relatively slowly. The dynamical modeling of the collision between the ejecta and the external shell, together with the observed evolution of the source size ( which is nicely reproduced in our model), suggests that most of the energy in the outflow was in mildly relativistic material, with an initial expansion velocity v/c <= d(15)(1 + d(15)(2))(-1/2) similar to 0.7, for a distance of 15d(15) kpc to SGR 1806-20. An initially highly relativistic outflow would not have produced a long coasting phase at a mildly relativistic expansion velocity, as was observed. C1 Stanford Univ, KIPAC, Stanford, CA 94309 USA. Inst Adv Study, Princeton, NJ 08540 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, George C Marshall Space Flight Ctr, NSSTC, Huntsville, AL 35805 USA. RP Granot, J (reprint author), Stanford Univ, KIPAC, POB 20450,MS 29, Stanford, CA 94309 USA. EM granot@slac.stanford.edu RI Gaensler, Bryan/F-8655-2010; LYUBARSKY, YURY/F-2362-2012; Gelfand, Joseph/F-1110-2015; OI Gelfand, Joseph/0000-0003-4679-1058; Wijers, Ralph/0000-0002-3101-1808; Gaensler, Bryan/0000-0002-3382-9558 NR 17 TC 35 Z9 35 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 FEB 10 PY 2006 VL 638 IS 1 BP 391 EP 396 DI 10.1086/497680 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100034 ER PT J AU Heap, SR Lanz, T Hubeny, I AF Heap, SR Lanz, T Hubeny, I TI Fundamental properties of O-type stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE Magellanic Clouds; stars : abundances; stars : atmospheres; stars : early-type; stars : fundamental parameters ID SMALL-MAGELLANIC-CLOUD; ULTRAVIOLET-SPECTROSCOPIC-EXPLORER; BLANKETED MODEL ATMOSPHERES; EFFECTIVE TEMPERATURE SCALE; B-TYPE STARS; SPECTRAL CLASSIFICATION; LOW METALLICITY; HOT STARS; QUANTITATIVE SPECTROSCOPY; ABSOLUTE MAGNITUDES AB We present a comprehensive analysis of high-resolution, far-ultraviolet HST STIS, FUSE, and optical spectra of 18 O stars in the Small Magellanic Cloud. Our analysis is based on the OSTAR2002 grid of NLTE metal-line-blanketed model atmospheres calculated with our code TLUSTY. We systematically explore and present the sensitivity of various UV and optical lines to different stellar parameters. We have obtained consistent fits of the UV and the optical spectrum to derive the effective temperature, surface gravity, surface composition, and microturbulent velocity of each star. Stellar radii, masses, and luminosities follow directly. For stars of the same spectral subtype, we find a general good agreement between effective temperature determinations obtained with TLUSTY, CMFGEN, and FASTWIND models, which are all lower than the standard T-eff calibration of O stars. We propose a new calibration between the spectral type and effective temperature based on our results from UV metal lines, as well as optical hydrogen and helium lines. The lower effective temperatures translate into ionizing luminosities that are smaller by a factor of 3 compared to luminosities inferred from previous standard calibrations. The chemical composition analysis reveals that the surface of about 80% of the program stars is moderately to strongly enriched in nitrogen, while showing the original helium, carbon, and oxygen abundances. Our results support the new stellar evolution models that predict that the surface of fast rotating stars becomes nitrogen-rich during the main-sequence phase because of rotationally induced mixing. Enrichment factors are, however, larger than predicted by stellar evolution models. Most stars exhibit the "mass discrepancy'' problem, which we interpret as a result of fast rotation that lowers the measured effective gravity. Nitrogen enrichment and low spectroscopic masses are therefore two manifestations of fast rotation. Our study thus emphasizes the importance of rotation in our understanding of the properties of massive stars and provides a framework for investigating populations of low-metallicity massive stars at low and high redshifts. C1 NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. RP Heap, SR (reprint author), NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. EM sara.r.heap@nasa.gov; tlanz@umd.edu; hubeny@as.arizona.edu NR 62 TC 55 Z9 55 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 FEB 10 PY 2006 VL 638 IS 1 BP 409 EP 432 DI 10.1086/498635 PN 1 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100036 ER PT J AU Borde, PJ Traub, WA AF Borde, PJ Traub, WA TI High-contrast imaging from space: Speckle nulling in a low-aberration regime SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation : adaptive optics; planetary systems; techniques : high angular resolution ID TERRESTRIAL PLANETS; DEFORMABLE MIRROR; CORONAGRAPH; TELESCOPES; IMAGES; COMPANION AB High-contrast imaging from space must overcome two major noise sources to successfully detect a terrestrial planet angularly close to its parent star: photon noise from diffracted starlight and speckle noise from starlight scattered by instrumentally generated wave front perturbation. Coronagraphs tackle only the photon noise contribution by reducing diffracted starlight at the location of a planet. Speckle noise should be addressed with adaptive optics systems. Following the tracks of Malbet, Yu, and Shao, we develop in this paper two analytical methods for wave front sensing and control that aims at creating "dark holes,'' i.e., areas of the image plane cleared of speckles, assuming an ideal coronagraph and small aberrations. The first method, "speckle field nulling,'' is a fast FFT-based algorithm that requires the deformable-mirror influence functions to have identical shapes. The second method, "speckle energy minimization,'' is more general and provides the optimal deformable mirror shape via matrix inversion. With an N x N deformable mirror, the size of the matrix to be inverted is either N-2 x N-2 in the general case or only N; N if the influence functions can be written as the tensor product of two one-dimensional functions. Moreover, speckle energy minimization makes it possible to trade off some of the dark hole area against an improved contrast. For both methods, complex wave front aberrations (amplitude and phase) are measured using just three images taken with the science camera (no dedicated wave front sensing channel is used); therefore, there are no noncommon path errors. We assess the theoretical performance of both methods with numerical simulations including realistic speckle noise and experimental influence functions. We find that these speckle-nulling techniques should be able to improve the contrast by several orders of magnitude. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM pborde@cfa.harvard.edu; wtraub@jpl.nasa.gov NR 24 TC 119 Z9 119 U1 0 U2 8 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 FEB 10 PY 2006 VL 638 IS 1 BP 488 EP 498 DI 10.1086/498669 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100043 ER PT J AU Bigazzi, A Biferale, L Gama, SMA Velli, M AF Bigazzi, A Biferale, L Gama, SMA Velli, M TI Small-scale anisotropy and intermittence in high- and low-latitude solar wind SO ASTROPHYSICAL JOURNAL LA English DT Article DE interplanetary medium; methods : data analysis; methods : statistical; solar wind; turbulence ID INTERPLANETARY MAGNETIC-FIELD; MAGNETOHYDRODYNAMIC TURBULENCE; HYDROMAGNETIC TURBULENCE; SHEAR-FLOW; FLUCTUATIONS; WAVES; DISSIPATION; EXPONENTS; EVOLUTION; TRANSPORT AB We study low- and high-latitude fast solar wind data from the Ulysses spacecraft from 1992 to 1994 using for the first time a systematic method to analyze the anisotropic content of the magnetic field fluctuations beyond second-order correlation functions. We investigate all available frequencies, 1-10(-6) Hz, for both high- and low- latitude data sets in which mean magnetic field points parallel and perpendicular to the mean flow, respectively, and we are able to quantify the relative importance of the anisotropic versus the isotropic fluctuations. We analyze, up to sixth order, longitudinal, transverse, and mixed magnetic field correlations. Our results show that strongly intermittent and anisotropic events persist even at high frequencies/small scales, indicating the absence of a complete recovery of isotropy. Our study shows for the first time the existence of intermittent anisotropic contributions at all scales in solar wind. Analyses of anomalous scaling of quantities that mix isotropic and anisotropic fluctuations, like longitudinal structure functions, may therefore be flawed by systematic uncontrolled errors. Anisotropic scaling properties are compatible for high- and low- latitude data, suggesting a universal behavior in spite of the different rate of evolution of the fast solar wind streams in the two environments. C1 Univ Roma Tor Vergata, Dept Elect Engn, I-00133 Rome, Italy. Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy. Univ Roma Tor Vergata, Ist Nazl Fis Nucl, I-00133 Rome, Italy. Univ Porto, CMUP, P-4169007 Oporto, Portugal. Univ Porto, Dept Matemat Aplicada, P-4169007 Oporto, Portugal. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. RP Bigazzi, A (reprint author), Univ Roma Tor Vergata, Dept Elect Engn, Via Politecn,1, I-00133 Rome, Italy. RI biferale, luca/L-4535-2013; OI Gama, Silvio/0000-0002-0852-8892 NR 51 TC 16 Z9 16 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 FEB 10 PY 2006 VL 638 IS 1 BP 499 EP 507 DI 10.1086/498665 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SF UT WOS:000235132100044 ER PT J AU Rykoff, ES Mangano, V Yost, SA Sari, R Aharonian, F Akerlof, CW Ashley, MCB Barthelmy, SD Burrows, DN Gehrels, N Gogus, E Guver, T Horns, D Kiziloglu, U Krimm, HA McKay, TA Ozel, M Phillips, A Quimby, RM Rowell, G Rujopakarn, W Schaefer, BE Smith, DA Swan, HF Vestrand, WT Wheeler, JC Wren, J Yuan, F AF Rykoff, ES Mangano, V Yost, SA Sari, R Aharonian, F Akerlof, CW Ashley, MCB Barthelmy, SD Burrows, DN Gehrels, N Gogus, E Guver, T Horns, D Kiziloglu, U Krimm, HA McKay, TA Ozel, M Phillips, A Quimby, RM Rowell, G Rujopakarn, W Schaefer, BE Smith, DA Swan, HF Vestrand, WT Wheeler, JC Wren, J Yuan, F TI The anomalous early afterglow of GRB 050801 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID GAMMA-RAY-BURSTS; OPTICAL AFTERGLOW; EMISSION; JETS; RADIATION AB The ROTSE-IIIc telescope at the HESS site, Namibia, obtained the earliest detection of optical emission from a gamma-ray burst (GRB), beginning only 21.8 s from the onset of Swift GRB 050801. The optical light curve does not fade or brighten significantly over the first similar to 250 s, after which there is an achromatic break and the light curve declines in typical power-law fashion. The Swift XRT also obtained early observations starting at 69 s after the burst onset. The X-ray light curve shows the same features as the optical light curve. These correlated variations in the early optical and X-ray emission imply a common origin in space and time. This behavior is difficult to reconcile with the standard models of early afterglow emission. C1 Univ Michigan, Randall Lab 2477, Ann Arbor, MI 48109 USA. INAF, Ist Astrofis Spaziale & Cosmica, I-90146 Palermo, Italy. CALTECH, Pasadena, CA 91125 USA. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Univ New S Wales, Dept Astrophys & Opt, Sch Phys, Sydney, NSW 2052, Australia. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20071 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Sabanci Univ, Fac Engn & nat Sci, TR-34956 Istanbul, Turkey. Univ Istanbul, Fac Sci, Dept Astron & Space Sci, TR-34119 Istanbul, Turkey. Middle E Tech Univ, TR-06531 Ankara, Turkey. Univ Space Res Assoc, Columbia, MD 21044 USA. Canakkale Osekiz Mart Univ, TR-17020 Canakkale, Turkey. Univ Texas, Dept Astron, Austin, TX 78712 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Guilford Coll, Greensboro, NC 27410 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rykoff, ES (reprint author), Univ Michigan, Randall Lab 2477, 450 Church St, Ann Arbor, MI 48109 USA. EM erykoff@umich.edu RI Guver, Tolga/C-1408-2011; Horns, Dieter/C-9727-2011; Gehrels, Neil/D-2971-2012; Barthelmy, Scott/D-2943-2012; Rujopakarn, Wiphu/E-7849-2012; McKay, Timothy/C-1501-2009; Guver, Tolga/B-1039-2014; OI McKay, Timothy/0000-0001-9036-6150; Guver, Tolga/0000-0002-3531-9842; Rujopakarn, Wiphu/0000-0002-0303-499X; Flewelling, Heather/0000-0002-1050-4056; Rowell, Gavin/0000-0002-9516-1581 NR 29 TC 37 Z9 37 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 FEB 10 PY 2006 VL 638 IS 1 BP L5 EP L8 DI 10.1086/501007 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SH UT WOS:000235132400002 ER PT J AU Teplitz, HI Armus, L Soifer, BT Charmandaris, V Marshall, JA Spoon, H Lawrence, C Hao, L Higdon, S Wu, Y Lacy, M Eisenhardt, PR Herter, T Houck, JR AF Teplitz, HI Armus, L Soifer, BT Charmandaris, V Marshall, JA Spoon, H Lawrence, C Hao, L Higdon, S Wu, Y Lacy, M Eisenhardt, PR Herter, T Houck, JR TI Silicate emission in the Spitzer IRS spectrum of FSC 10214+4724 SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; galaxies : evolution; galaxies : high-redshift; galaxies : individual (FSC 10214+4724) ID IRAS SOURCE FSC-10214+4724; INFRARED SPECTROGRAPH IRS; SPACE-TELESCOPE; ACTIVE GALAXIES; MOLECULAR GAS; ISO-SWS; SPECTROSCOPY; DUST; F10214+4724; DIAGNOSTICS AB We present the first mid-infrared (MIR) spectrum of the z = 2.2856 ultraluminous infrared galaxy FSC 10214 + 4724, obtained with the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. The spectrum spans a rest-wavelength range of 2.3 - 11.5 mu m, covering a number of key diagnostic emission and absorption features. The most prominent feature in the IRS spectrum is the silicate emission at rest-frame similar to 10 mu m. We also detect an unresolved emission line at a rest wavelength of 7.65 mu m that we identify with [Ne VI], and a slightly resolved feature at 5.6 mu m identified as a blend of [Mg VII] and [Mg V]. There are no strong PAH emission features in the FSC 10214 + 4724 spectrum. We place a limit of 0.1 mu m on the equivalent width of 6.2 mu m PAH emission but see no evidence of a corresponding 7.7 mu m feature. Semiempirical fits to the spectral energy distribution suggest that similar to 45% of the bolometric luminosity arises from cold (similar to 50 K) dust, half arises from warm ( 190 K) dust, and the remainder, similar to 5%, originates from hot (similar to 640 K) dust. The hot dust is required to fit the blue end of the steep MIR spectrum. The combination of a red continuum, strong silicate emission, little or no PAH emission, and no silicate absorption makes FSC 10214 + 4724 unlike most other ULIRGs or AGNs observed thus far with the IRS. These apparently contradictory properties may be explained by an AGN that is highly magnified by the lens, masking a ( dominant) overlying starburst with unusually weak PAH emission. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Observ Paris, F-75014 Paris, France. Univ Crete, Dept Phys, GR-71003 Iraklion, Greece. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Teplitz, HI (reprint author), CALTECH, Spitzer Sci Ctr, Mail Code 220-6,1200 E Calif Blvd, Pasadena, CA 91125 USA. EM hit@ipac.caltech.edu RI Charmandaris, Vassilis/A-7196-2008; Wu, Yanling/A-1261-2010 OI Charmandaris, Vassilis/0000-0002-2688-1956; NR 36 TC 30 Z9 30 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 FEB 10 PY 2006 VL 638 IS 1 BP L1 EP L4 DI 10.1086/500791 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SH UT WOS:000235132400001 ER PT J AU Diuk-Wasser, MA Dolo, G Bagayoko, M Sogoba, N Toure, MB Moghaddam, M Manoukis, N Rian, S Traore, SF Taylor, CE AF Diuk-Wasser, MA Dolo, G Bagayoko, M Sogoba, N Toure, MB Moghaddam, M Manoukis, N Rian, S Traore, SF Taylor, CE TI Patterns of irrigated rice growth and malaria vector breeding in Mali using multi-temporal ERS-2 synthetic aperture radar SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID C-BAND SAR; INTERMITTENT IRRIGATION; LARVIVOROUS PREDATORS; MOSQUITOS DIPTERA; WEST-AFRICA; KISUMU AREA; SENSOR DATA; FIELDS; CULTIVATION; CULICIDAE AB We explored the use of the European Remote Sensing Satellite 2 Synthetic Aperture Radar (ERS-2 SAR) to trace the development of rice plants in an irrigated area near Niono, Mali and relate that to the density of anopheline mosquitoes, especially An. gambiae. This is important because such mosquitoes are the major vectors of malaria in sub-Saharan Africa, and their development is often coupled to the cycle of rice development. We collected larval samples, mapped rice fields using GPS and recorded rice growth stages simultaneously with eight ERS-2 SAR acquisitions. We were able to discriminate among rice growth stages using ERS-2 SAR backscatter data, especially among the early stages of rice growth, which produce the largest numbers of larvae. We could also distinguish between basins that produced high and low numbers of anophelines within the stage of peak production. After the peak, larval numbers dropped as rice plants grew taller and thicker, reducing the amount of light reaching the water surface. ERS-2 SAR backscatter increased concomitantly. Our data support the belief that ERS-2 SAR data may be helpful for mapping the spatial patterns of rice growth, distinguishing different agricultural practices, and monitoring the abundance of vectors in nearby villages. C1 Yale Univ, Sch Med, Dept Epidemiol & Publ Hlth, New Haven, CT 06520 USA. Univ Calif Los Angeles, Dept Organism Biol Ecol & Evolut, Los Angeles, CA 90024 USA. Univ Mali, Fac Med Pharm & Odontostomatol, Malaria Res & Training Ctr, Bamako, Mali. Jet Propuls Lab, Pasadena, CA USA. RP Yale Univ, Sch Med, Dept Epidemiol & Publ Hlth, New Haven, CT 06520 USA. EM maria.diuk@yale.edu RI Song, Sigrid Rian/J-8427-2016 OI Song, Sigrid Rian/0000-0002-8131-8074 FU NIAID NIH HHS [R01 AI051633-01] NR 35 TC 12 Z9 13 U1 0 U2 10 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0143-1161 EI 1366-5901 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD FEB 10 PY 2006 VL 27 IS 3 BP 535 EP 548 PG 14 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 029PI UT WOS:000236576200007 PM 17710188 ER PT J AU Rubinstein, R Girimaji, SS AF Rubinstein, R Girimaji, SS TI Second moment closure near the two-component limit SO JOURNAL OF FLUID MECHANICS LA English DT Article ID TURBULENCE MODELS; REALIZABILITY AB The hypothesis that turbulence evolution can be described by kinetic energy, dissipation, and the Reynolds stresses alone is the basis of current second moment closures. This hypothesis is shown to be inconsistent with the Navier-Stokes equations at the two-component limit, because it implies that initially two-component turbulence remains two-component for all times. The inconsistency can be traced to the Markovian stress evolution imposed by the hypothesis; even Markovian spectral closures cannot predict evolution from a two-component initial state. Some implications of these findings for imposing realizability constraints on turbulence models are discussed. C1 NASA, Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA. Texas A&M Univ, Dept Aerosp & Mech Engn, College Stn, TX USA. RP Rubinstein, R (reprint author), NASA, Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD FEB 10 PY 2006 VL 548 BP 197 EP 206 DI 10.1017/S0022112005007792 PG 10 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 015TU UT WOS:000235574700011 ER PT J AU Li, ZH Fielding, EJ Cross, P Muller, JP AF Li, ZH Fielding, EJ Cross, P Muller, JP TI Interferometric synthetic aperture radar atmospheric correction: GPS topography-dependent turbulence model SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID SAR INTERFEROGRAMS; INTERPOLATION; DEFORMATION; DELAY; ETNA AB [1] Over the last two decades, repeat pass interferometric synthetic aperture radar (InSAR) has been widely used as a geodetic technique for measuring the Earth's surface, including topography and deformation. Like other astronomical and space geodetic techniques, repeat pass InSAR is limited by the variable spatial and temporal distribution of atmospheric water vapor. In this paper, a topography-dependent turbulence model (GTTM for short) has been developed using GPS data only to produce zenith path delay difference maps for InSAR atmospheric correction. Application of the GTTM model to ERS Tandem data over the Los Angeles Southern California Integrated GPS Network area has shown that use of the GTTM can reduce water vapor effects on interferograms from similar to 10 mm down to similar to 5 mm, which is of great interest to a wide community of geophysicists. The principal finding of this paper is that interpolation methods should be applied to zenith total delay (ZTD) differences from different times instead of ZTD values themselves for the purpose of InSAR atmospheric correction. This is crucial to reduce ( if not completely remove) topographic effects on ZTD values. C1 UCL, Dept Geomat Engn, London WC1E 6BT, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Li, ZH (reprint author), UCL, Dept Geomat Engn, Gower St, London WC1E 6BT, England. EM zhli@ge.ucl.ac.uk RI NCEO, COMET+`/A-3443-2013; Li, Zhenhong/F-8705-2010; Fielding, Eric/A-1288-2007; OI Li, Zhenhong/0000-0002-8054-7449; Fielding, Eric/0000-0002-6648-8067; Muller, Jan-Peter/0000-0002-5077-3736 NR 32 TC 50 Z9 53 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD FEB 10 PY 2006 VL 111 IS B2 AR B02404 DI 10.1029/2005JB003711 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 012TZ UT WOS:000235364300001 ER PT J AU Wang, HJ Cunnold, DM Trepte, C Thomason, LW Zawodny, JM AF Wang, HJ Cunnold, DM Trepte, C Thomason, LW Zawodny, JM TI SAGE III solar ozone measurements: Initial results SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID QUALITY; AEROSOL AB Results from two retrieval algorithms, "o3_aer'' and "o3_mlr'', used for SAGE III solar occultation ozone measurements in the stratosphere and upper troposphere are compared. The main differences between these two retrieved ( version 3.0) ozone are found at altitudes above 40 km and below 15 km. Compared to correlative measurements, the SAGE II type ozone retrievals (o3_aer) provide better precisions above 40 km and do not induce artificial hemispheric differences in upper stratospheric ozone. The multiple linear regression technique (o3_mlr), however, can yield slightly more accurate ozone ( by a few percent) in the lower stratosphere and upper troposphere. By using SAGE III ( version 3.0) ozone from both algorithms and in their preferred regions, the agreement between SAGE III and correlative measurements is shown to be similar to 5% down to 17 km. Below 17 km SAGE III ozone values are systematically higher, by 10% at 13 km, and a small hemispheric difference ( a few percent) appears. Compared to SAGE III and HALOE, SAGE II ozone has the best accuracy in the lowest few kilometers of the stratosphere. Estimated precision in SAGE III ozone is about 5% or better between 20 and 40 km and similar to 10% at 50 km. The precision below 20 km is difficult to evaluate because of limited coincidences between SAGE III and sondes. SAGE III ozone values are systematically slightly larger ( 2 - 3%) than those from SAGE II but the profile shapes are remarkably similar for altitudes above 15 km. There is no evidence of any relative drift or time dependent differences between these two instruments for altitudes above 15 - 20 km. C1 Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Wang, HJ (reprint author), Georgia Inst Technol, Sch Earth & Atmospher Sci, 311 Ferst Dr, Atlanta, GA 30332 USA. EM raywang@eas.gatech.edu NR 9 TC 12 Z9 12 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 FEB 8 PY 2006 VL 33 IS 3 AR L03805 DI 10.1029/2005GL025099 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 012TD UT WOS:000235361700007 ER PT J AU Sauber, J Carver, G Cohen, S King, R AF Sauber, J Carver, G Cohen, S King, R TI Crustal deformation and the seismic cycle across the Kodiak Islands, Alaska SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID WILLIAM-SOUND EARTHQUAKE; SOUTH CENTRAL ALASKA; SUBDUCTION ZONE; KENAI PENINSULA; STRAIN ACCUMULATION; UPLIFT; PLATE; SLIP; CONSTRAINTS; MODELS AB [1] The Kodiak Islands are located similar to 120 to 250 km from the Alaska-Aleutian Trench and are within the southern extent of the 1964 Prince William Sound (M-w = 9.2) earthquake rupture and aftershock zone. Here we report new campaign GPS results ( 1993 - 2001) from northeastern Kodiak and reprocessed GPS results ( 1993 - 1997) from southwestern Kodiak. The rate and orientation of the horizontal velocities, relative to a fixed North America, range from 29.7 +/- 1.7 mm/yr at N30.3 degrees W +/- 3.3 degrees, located similar to 120 km from the deepest point of the trench, to 8.0 +/- 1.3 mm/yr at N62.4 degrees W +/- 9.3 degrees, located similar to 230 km from the trench. We evaluated alternate models of coseismic and interseismic slip to test the importance of the mechanisms that account for surface deformation rates. Near the Gulf of Alaska coastal region of Kodiak the horizontal velocity can be accounted for primarily by the viscoelastic response to plate motion and a locked main thrust zone (MTZ), downdip creep, and to a lesser extent, slip in the 1964 earthquake. Farther inland the dominant mechanisms that account for post-1964 uplift rates are time-dependent, downdip creep and a locked MTZ; for the horizontal velocity component, southwest translation of western Kodiak may be important as well. On the basis of the pre-1964 and post-1964 earthquake pattern of interseismic earthquakes, we suggest that between the occurrences of great earthquakes like the 1964 event, more moderate to large earthquakes occur in the southwestern Kodiak region than near northeastern Kodiak. C1 NASA, Planetary Geodynam Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Humboldt State Univ, Dept Geol, Arcata, CA 95521 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. RP Sauber, J (reprint author), NASA, Planetary Geodynam Lab, Goddard Space Flight Ctr, Code 921, Greenbelt, MD 20771 USA. EM jeanne.m.sauber-rosenberg@nasa.gov RI Sauber, Jeanne/D-7684-2012 NR 65 TC 7 Z9 7 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-SOL EA JI J. Geophys. Res.-Solid Earth PD FEB 8 PY 2006 VL 111 IS B2 AR B02403 DI 10.1029/2005JB003626 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 012TX UT WOS:000235364000002 ER PT J AU Lillis, RJ Manga, M Mitchell, DL Lin, RP Acuna, MH AF Lillis, RJ Manga, M Mitchell, DL Lin, RP Acuna, MH TI Unusual magnetic signature of the Hadriaca Patera volcano: Implications for early Mars SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID THERMAL EVOLUTION; MARTIAN CORE; FIELD; DYNAMO; THARSIS; REGION; MANTLE AB Typically, Martian volcanoes show either a total absence of crustal magnetism or a local magnetic mimimum. Hadriaca Patera is the only volcano on Mars with a clear positive magnetic anomaly directly over the volcanic edifice, as determined by electron reflection magnetometry. Hadriaca's topography, lava flow crater ages, gravity anomaly, position relative to the Hellas rim and past aqueous environment provide geological constraints on possible scenarios to explain this unusual magnetic signature. The two most probable scenarios are a) pre-Hellas thermoremanent magnetization (TRM) of a deep-seated magma body followed by post-Hellas intrusive partial thermal demagnetization and b) post-Hellas emplacement of the volcano and TRM in a global magnetic field. It is thus likely that Mars had at least one of the following: highland volcanism in pre-Hellas times (older than any datable volcanic feature on the planet) or an active dynamo some time after the Hellas impact. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94720 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lillis, RJ (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. EM rlillis@ssl.berkeley.edu RI Manga, Michael/D-3847-2013; Lillis, Robert/A-3281-2008; OI Lillis, Robert/0000-0003-0578-517X; Manga, Michael/0000-0003-3286-4682 NR 29 TC 20 Z9 20 U1 1 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 FEB 4 PY 2006 VL 33 IS 3 AR L03202 DI 10.1029/2005GL024905 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 010AZ UT WOS:000235156900003 ER PT J AU Alexander, DA Deen, RG Andres, PM Zamani, P Mortensen, HB Chen, AC Cayanan, MK Hall, JR Klochko, VS Pariser, O Stanley, CL Thompson, CK Yagi, GM AF Alexander, DA Deen, RG Andres, PM Zamani, P Mortensen, HB Chen, AC Cayanan, MK Hall, JR Klochko, VS Pariser, O Stanley, CL Thompson, CK Yagi, GM TI Processing of Mars Exploration Rover imagery for science and operations planning SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID CAMERAS AB The twin Mars Exploration Rovers (MER) delivered an unprecedented array of image sensors to the Mars surface. These cameras were essential for operations, science, and public engagement. The Multimission Image Processing Laboratory (MIPL) at the Jet Propulsion Laboratory was responsible for the first-order processing of all of the images returned by these cameras. This processing included reconstruction of the original images, systematic and ad hoc generation of a wide variety of products derived from those images, and delivery of the data to a variety of customers, within tight time constraints. A combination of automated and manual processes was developed to meet these requirements, with significant inheritance from prior missions. This paper describes the image products generated by MIPL for MER and the processes used to produce and deliver them. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM doug.alexander@jpl.nasa.gov NR 25 TC 25 Z9 28 U1 3 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 FEB 4 PY 2006 VL 111 IS E2 AR E02S02 DI 10.1029/2005JE002462 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 010BK UT WOS:000235158400001 ER PT J AU Johnson, JR Grundy, WM Lemmon, MT Bell, JF Johnson, MJ Deen, RG Arvidson, RE Farrand, WH Guinness, EA Hayes, AG Herkenhoff, KE Seelos, F Soderblom, J Squyres, S AF Johnson, JR Grundy, WM Lemmon, MT Bell, JF Johnson, MJ Deen, RG Arvidson, RE Farrand, WH Guinness, EA Hayes, AG Herkenhoff, KE Seelos, F Soderblom, J Squyres, S TI Spectrophotometric properties of materials observed by Pancam on the Mars Exploration Rovers: 1. Spirit SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID GUSEV CRATER; PHOTOMETRIC PROPERTIES; REFLECTANCE SPECTROSCOPY; SCATTERING PROPERTIES; SURFICIAL DEPOSITS; LIGHT-SCATTERING; MARTIAN SURFACE; LANDING SITE; REGOLITH; ROCKS AB Multispectral observations of rocks and soils were acquired under varying illumination and viewing geometries in visible/near-infrared wavelengths by the Panoramic Camera (Pancam) on the Spirit Mars Exploration Rover to provide constraints on the physical and mineralogical nature of geologic materials in Gusev Crater. Data sets were acquired at six sites located near the landing site, in the surrounding plains, and in the West Spur and Husband Hill regions of the Columbia Hills. From these similar to 600 images, over 10,000 regions of interest were selected of rocks and soils over a wide range of phase angles (0-130 degrees). Corrections for diffuse skylight incorporated sky models based on observations of atmospheric opacity throughout the mission. Disparity maps created from Pancam stereo images allowed inclusion of estimates of local facet orientations in the sky models. Single-term and two-term phase functions derived from Hapke scattering models exhibit a dominantly broad backscattering trend for soils and "Red'' rocks inferred to be covered with variable amounts of dust and other coatings, consistent with the results from the Viking Lander and Imager for Mars Pathfinder cameras. Darker "Gray'' rock surfaces ( inferred to be relatively less dust covered) display more narrow, forward scattering behaviors, consistent with particles exhibiting little internal scattering. Gray and Red rocks are macroscopically rougher than most soil units, although a "dust-cleaning'' event observed near the Paso Robles site caused an increase in soil surface roughness in addition to a substantial decrease in surface single scattering albedo. Gray rocks near the rim of Bonneville Crater exhibit the largest macroscopic roughness ((theta) over bar) among all units, as well as the greatest backscattering among Gray rocks. Photometric properties of coated Red rocks vary in the West Spur region, possibly as a result of weathering differences related to elevation-dependent aeolian regimes. C1 US Geol Survey, Astrogeol Team, Flagstaff, AZ 86001 USA. Texas A&M Univ, Dept Atmospher Sci, College Stn, TX USA. Lowell Observ, Flagstaff, AZ 86001 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Space Sci Inst, Boulder, CO USA. RP US Geol Survey, Astrogeol Team, 2255 N Gemini Dr, Flagstaff, AZ 86001 USA. EM jrjohnson@usgs.gov RI Johnson, Jeffrey/F-3972-2015; Kinch, Kjartan/C-5742-2015; Hayes, Alexander/P-2024-2014; Seelos, Frank/C-7875-2016; Lemmon, Mark/E-9983-2010 OI Soderblom, Jason/0000-0003-3715-6407; Kinch, Kjartan/0000-0002-4629-8880; Hayes, Alexander/0000-0001-6397-2630; Seelos, Frank/0000-0001-9721-941X; Lemmon, Mark/0000-0002-4504-5136 NR 65 TC 58 Z9 59 U1 0 U2 2 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 FEB 4 PY 2006 VL 111 IS E2 AR E02S14 DI 10.1029/2005JE002494 PG 39 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 010BK UT WOS:000235158400002 ER PT J AU Aksnes, A Stadsnes, J Ostgaard, N Germany, GA Oksavik, K Vondrak, RR Brekke, A Lovhaug, UP AF Aksnes, A Stadsnes, J Ostgaard, N Germany, GA Oksavik, K Vondrak, RR Brekke, A Lovhaug, UP TI Height profiles of the ionospheric electron density derived using space-based remote sensing of UV and X ray emissions and EISCAT radar data: A ground-truth experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID POLAR ULTRAVIOLET IMAGER; ENERGETIC ELECTRONS; AURORAL IONIZATION; GEOMAGNETIC INDEXES; PRECIPITATION; TRANSPORT; ATMOSPHERE; DEPOSITION; SUBSTORMS; CONDUCTANCES AB In this study we have derived height profiles of the ionospheric electron density N-e using remote sensing of UV and X-ray emissions from the Polar satellite and EISCAT radar data. The latter technique gives the most accurate determination of N-e providing a means to ground-truthing the satellite imaging measurements. The UV-emission data are taken from the Ultraviolet Imager (UVI) on Polar, while the X-ray data are measured by the Polar Ionospheric X-ray Imaging Experiment (PIXIE). As UVI yields a far better resolution in time and space than PIXIE, our primary approach involves UVI and EISCAT data. For a substorm event occurring on 24 March 1998, we derive Ne-UVI profiles valid in the E region above similar to 105 km. By comparing with simultaneous Ne-EISCAT values, we find that the two techniques match fairly well in many cases. The altitude of maximum electron density is usually below 110 km. A few cases reveal Ne-EISCAT maxima in the upper E region (130-150 km), indicating a very soft precipitating electron energy spectrum. During such conditions, we observe the largest discrepancies between the Ne-UVI and Ne-EISCAT profiles. This may reflect the difficulty of obtaining proper energy characteristics from UV emissions, when the mean electron energy is less than similar to 2 keV. A recalculation of these Ne-UVI values has been performed, requiring that the altitudes of the Ne-UVI maximum must match the altitudes of the Ne-EISCAT maximum. The results reveal a much better agreement between the two data sets, suggesting that UVI is measuring about the same energy flux as EISCAT. Even though the modified Ne-UVI values deviate strongly from the old Ne-UVI profiles, the effects on the Pedersen conductance, Sigma(P), are insignificant. Also, we find that Sigma(P-UVI) are within +/- 30% of Sigma(P-EISCAT) for 15 of 18 cases, suggesting that remote sensing of UV-emissions provide a fairly reliable tool to monitor the Pedersen conductance. We have investigated a second approach by including PIXIE X-ray data to derive Ne-UVI+PIXIE values valid in the whole E region and upper D region. Despite the coarse PIXIE resolution, we observe a fairly good match with the Ne-EISCAT profiles. By calculating the Hall and Pedersen conductances, Sigma(H) and Sigma(P), we find that the values derived from satellite imaging measurements are within +/- 25% of the EISCAT values for all four cases, supporting the space-based remote sensing technique to investigate the ionospheric electrodynamics. The results presented in this study suggest that the procedures developed to derive N-e values from the satellite imaging measurements are reliable. We also find that the Ne-UVI and Ne-UVI+PIXIE values on average are slightly larger (5 and 13%) than the Ne-EISCAT values. These discrepancies may be caused by the difference in resolution between the satellite remote sensing data and the radar data, as smoothing of discrete precipitation may result in an overestimation of N-e. C1 Univ Bergen, Dept Phys & Technol, N-5007 Bergen, Norway. Univ Alabama, Ctr Space Plasma & Astron Res, Huntsville, AL 35899 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Tromso, Dept Phys, N-9037 Tromso, Norway. RP Aksnes, A (reprint author), Florida Space Inst, MS FSI, Kennedy Space Ctr, FL 32899 USA. EM aaksnes@mail.ucf.edu; johan.stadsnes@ift.uib.no; nikost@ift.uib.no; germanyg@email.uah.edu; kjellmar.oksavik@jhuapl.edu; richard.r.vondrak@nasa.gov; asgeir.brekke@phys.uit.no; unni.pia.lovhaug@phys.uit.no OI Oksavik, Kjellmar/0000-0003-4312-6992 NR 50 TC 5 Z9 5 U1 0 U2 1 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 FEB 3 PY 2006 VL 111 IS A2 AR A02301 DI 10.1029/2005JA011331 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 010BP UT WOS:000235159200002 ER PT J AU Stanford, MK DellaCorte, C AF Stanford, MK DellaCorte, C TI Atomization of metal fluorides for enhanced flow characteristics of a multicomponent powder SO POWDER TECHNOLOGY LA English DT Article DE atomization; comminution; flow; image analysis; particle shape classification ID PS304 AB The National Aeronautics and Space Administration's (NASA's) PS304 coating is a plasma spray deposited tribological coating with feedstock composed of NiCr, Cr2O3, Ag and BaF2-CaF2, powders. The effects of rounded BaF2-CaF2, particles on the gravity-fed flow characteristics of PS304 feedstock have been investigated. The BaF2-CaF2, powder was fabricated by water atomization using four sets of process parameters. Each of these powders was then characterized by microscopy and classified by screening to obtain 45-106 mu m particles and added incrementally from 0-10 wt.% to the other constituents of the PS304 feedstock, namely nichrome, chromia and silver powders. The relationship between feedstock flow rate, measured with the Hall flowmeter, and concentration of fluorides was found to be linear in each case. The slopes of the lines were between those of the linear relationships previously reported using angular and spherical fluorides and were closer to the relationship predicted using the rule of mixtures. The results offer a fluoride fabrication technique potentially more cost-effective than gas atomization processes or traditional comminution processes. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. RP Stanford, MK (reprint author), NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. EM malcolm.k.stanford@nasa.gov NR 27 TC 1 Z9 1 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD FEB 3 PY 2006 VL 161 IS 3 BP 190 EP 195 DI 10.1016/j.powtec.2005.11.001 PG 6 WC Engineering, Chemical SC Engineering GA 011XF UT WOS:000235301300004 ER PT J AU Taguchi, S Hosokawa, K Nakao, A Collier, MR Moore, TE Yamazaki, A Sato, N Yukimatu, AS AF Taguchi, S Hosokawa, K Nakao, A Collier, MR Moore, TE Yamazaki, A Sato, N Yukimatu, AS TI Neutral atom emission in the direction of the high-latitude magnetopause for northward IMF: Simultaneous observations from IMAGE spacecraft and SuperDARN radar SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOLAR-WIND CONDITIONS; RECONNECTION AB During a northward interplanetary magnetic field on 27 March 2001, the Low Energy Neutral Atom (LENA) imager on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft in the magnetosphere observed an enhanced emission in the direction of the very high-latitude magnetopause. Simultaneous observations from IMAGE/LENA and SuperDARN radar show that the LENA emission appears concurrently with the enhancement of the sunward flow of the reverse convection in the ionosphere. The field line mapping from the magnetosphere to the ionosphere suggests that the source ions for the LENA emission are in the sunward flow region. Although the direction of the emission is relatively stable, its direction changes slightly so that the emission may shift poleward or equatorward. From these observations, we suggest that LENA can monitor the ion entry caused by cusp reconnection and that the reconnection site moves on a timescale of several minutes. C1 Univ Electrocommun, Dept Informat & Commun Engn, Tokyo 1828585, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Tohoku Univ, Grad Sch Sci, Sendai, Miyagi 9808578, Japan. Natl Inst Polar Res, Tokyo 1738515, Japan. RP Taguchi, S (reprint author), Univ Electrocommun, Dept Informat & Commun Engn, Tokyo 1828585, Japan. EM taguchi@ice.uec.ac.jp RI Moore, Thomas/D-4675-2012; Collier, Michael/I-4864-2013 OI Moore, Thomas/0000-0002-3150-1137; Collier, Michael/0000-0001-9658-6605 NR 16 TC 7 Z9 7 U1 0 U2 4 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 FEB 2 PY 2006 VL 33 IS 3 AR L03101 DI 10.1029/2005GL025020 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 010AW UT WOS:000235156600005 ER PT J AU Feingold, G Furrer, R Pilewskie, P Remer, LA Min, QL Jonsson, H AF Feingold, G Furrer, R Pilewskie, P Remer, LA Min, QL Jonsson, H TI Aerosol indirect effect studies at Southern Great Plains during the May 2003 Intensive Operations Period SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLOUD OPTICAL DEPTH; SATELLITE; ALBEDO; INSTRUMENT; RADIOMETER; STRATUS; MICROPHYSICS; PARAMETERS; TRANSPORT; POLLUTION AB During May 2003 the Department of Energy's Atmospheric Radiation Measurement Program conducted an Intensive Operations Period (IOP) to measure the radiative effects of aerosol and clouds. A suite of both in situ and remote sensing measurements were available to measure aerosol and cloud parameters. This paper has three main goals: First, it focuses on comparison between in situ retrievals of the radiatively important drop effective radius r(e) and various satellite, airborne, and surface remote sensing retrievals of the same parameter. On 17 May 2003, there was a fortuitous, near-simultaneous sampling of a stratus cloud by five different methods. The retrievals of r(e) agree with one another to within similar to 20%, which is approximately the error estimate for most methods. Second, a methodology for deriving a best estimate of r(e) from these different instruments, with their different physical properties and sampling volumes, is proposed and applied to the 17 May event. Third, the paper examines the response of r(e) to changes in aerosol on 3 days during the experiment and examines the consistency of remote sensing and in situ measurements of the effect of aerosol on r(e). It is shown that in spite of the generally good agreement in derived r(e), the magnitude of the response of r(e) to changes in aerosol is quite sensitive to the method of retrieving r(e) and to the aerosol proxy for cloud condensation nuclei. Nonphysical responses are sometimes noted, and it is suggested that further work needs to be done to refine these techniques. C1 NOAA, Environm Technol Lab, Boulder, CO 80305 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Colorado, Atmospher & Space Phys Lab, Programm Atmospher & Ocean Sci, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12203 USA. USN, Postgrad Sch, Ctr Disciplinary Remotely Piloted Aircraft Studie, Monterey, CA 93933 USA. RP Feingold, G (reprint author), NOAA, Environm Technol Lab, 325 Broadway, Boulder, CO 80305 USA. EM graham.feingold@noaa.gov; furrer@ucar.edu; peter.pilewskie@lasp.colorado.edu; lorraine.a.remer@nasa.gov; min@asrc.cestm.albany.edu; hjonsson@nps.edu RI Furrer, Reinhard/A-4580-2011; Feingold, Graham/B-6152-2009; Manager, CSD Publications/B-2789-2015 OI Furrer, Reinhard/0000-0002-6319-2332; NR 43 TC 37 Z9 37 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 FEB 2 PY 2006 VL 111 IS D5 AR D05S14 DI 10.1029/2004JD005648 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 010BH UT WOS:000235157900001 ER PT J AU Masek, JG Collatz, GJ AF Masek, Jeffrey G. Collatz, G. James TI Estimating forest carbon fluxes in a disturbed southeastern landscape: Integration of remote sensing, forest inventory, and biogeochemical modeling SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES LA English DT Article ID NET PRIMARY PRODUCTIVITY; LONG-TERM; UNITED-STATES; LOBLOLLY-PINE; ECOSYSTEM PRODUCTION; BOREAL FOREST; SOIL CARBON; US FORESTS; LAND; ACCUMULATION AB Quantifying carbon fluxes between the atmosphere and land surface requires detailed knowledge of the disturbance regime as well as the photosynthetic response of vegetation to climate. In this study, we use a combination of satellite remote sensing, forest inventory data, and biogeochemical modeling to assess forest carbon fluxes from central Virginia, a landscape pervasively disturbed by harvest. Using historical Landsat imagery, we have reconstructed the disturbance history and age structure of forest stands at a resolution of 90 m, from 1973 - 1999. Forest inventory data provide breakdowns of forest type and age structure for older stands. These data, together with climate and vegetation greenness from advanced very high resolution radiometer (AVHRR), are used as inputs to a version of the Carnegie-Stanford-Ames (CASA) biogeochemical model, which simulates the uptake, allocation, and respiration of carbon and associated effects of disturbance. Modeling results indicate that forests in the study region have an average net ecosystem productivity (NEP) of similar to 80 gC m(-2) yr(-1), reflecting the young age structure of rapid-rotation forests. Variability in annual forest carbon fluxes due to variations in clearing rate and climate are also examined. We find that observed variations in clearing rate may account for NEP variability of similar to 30 gC m(-2) yr(-1), while observed variations in climate may account for NEP variability of 80 - 130 gC m(-2) yr(-1). Increased temperatures tend to drive both increased photosynthesis and increased heterotrophic respiration, buffering the system from larger swings in NEP. However, this response depends strongly on stand age. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. RP Masek, JG (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. EM jeffrey.g.masek@nasa.gov RI collatz, george/D-5381-2012; Masek, Jeffrey/D-7673-2012 NR 56 TC 43 Z9 45 U1 2 U2 23 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-8953 EI 2169-8961 J9 J GEOPHYS RES-BIOGEO JI J. Geophys. Res.-Biogeosci. PD FEB 2 PY 2006 VL 111 IS G1 AR G01006 DI 10.1029/2005JG000062 PG 15 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 090WW UT WOS:000240985600002 ER PT J AU Prezeau, G AF Prezeau, G TI Light neutrino and heavy particle exchange in Ov beta beta-decay SO PHYSICS LETTERS B LA English DT Article DE neutrinoless double-beta decay; neutrino ID LEFT-RIGHT SYMMETRY; SUPERSYMMETRIC THEORIES; PARITY AB A simple and precise method is presented to compare contributions to neutrinoless double-beta decay (0v beta beta-decay) from heavy particle exchange and light Majorana neutrino exchange. This procedure makes no assumptions about the momentum transfer between the two nucleons involved in the 0v beta beta-decay process. It is shown that for a general particle physics model, the characteristic 0v beta beta-decay scale > 4.4 TeV when all the coupling constants are assumed to be natural and of O(1). (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Prezeau, G (reprint author), CALTECH, Jet Propuls Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM gprezeau@mail.jpl.nasa.gov NR 21 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD FEB 2 PY 2006 VL 633 IS 1 BP 93 EP 97 DI 10.1016/j.physletb.2005.11.048 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 009GA UT WOS:000235098400016 ER PT J AU Holliday, JR Rundle, JB Tiampo, KF Klein, W Donnellan, A AF Holliday, JR Rundle, JB Tiampo, KF Klein, W Donnellan, A TI Modification of the pattern informatics method for forecasting large earthquake events using complex eigenfactors SO TECTONOPHYSICS LA English DT Article DE complex principal components; pattern informatics; earthquake forecasting ID PRINCIPAL COMPONENT ANALYSIS; PREDICTION; CALIFORNIA; DYNAMICS AB Recent studies have shown that real-valued principal component analysis can be applied to earthquake fault systems for forecasting and prediction. In addition, theoretical analysis indicates that earthquake stresses may obey a wave-like equation, having solutions with inverse frequencies for a given fault similar to those that characterize the time intervals between the largest events oil the fault. It is therefore desirable to apply complex principal component analysis to develop earthquake forecast algorithms. In this paper we modify the Pattern Informatics method of earthquake forecasting to take advantage of the wave-like properties of seismic stresses and utilize the Hilbert transform to create complex eigenvectors out of measured time series. We show that Pattern Informatics analyses using complex eigenvectors create short-term forecast hot-spot maps that differ from hot-spot maps created using only real-valued data and suggest methods of analyzing the differences and calculating the information gain. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Calif Davis, Ctr Computat Sci & Engn, Davis, CA 95616 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Western Ontario, Dept Earth Sci, London, ON, Canada. Boston Univ, Dept Phys, Boston, MA 02215 USA. CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA USA. RP Holliday, JR (reprint author), Univ Calif Davis, Ctr Computat Sci & Engn, Davis, CA 95616 USA. EM holliday@cse.ucdavis.edu; jbrundle@ucdavis.edu; ktiampo@uwo.ca; klein@buphyc.bu.edu; donnellan@jpl.nasa.gov RI Tiampo, Kristy/I-1355-2015 OI Tiampo, Kristy/0000-0002-5500-7600 NR 22 TC 21 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-1951 J9 TECTONOPHYSICS JI Tectonophysics PD FEB 2 PY 2006 VL 413 IS 1-2 BP 87 EP 91 DI 10.1016/j.tecto.2005.10.008 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 011MU UT WOS:000235273200010 ER PT J AU Rundle, JB Rundle, PB Donnellan, A Li, P Klein, W Morein, G Turcotte, DL Grant, L AF Rundle, JB Rundle, PB Donnellan, A Li, P Klein, W Morein, G Turcotte, DL Grant, L TI Stress transfer in earthquakes, hazard estimation and ensemble forecasting: Inferences from numerical simulations SO TECTONOPHYSICS LA English DT Article DE earthquakes; numerical simulations; virtual California ID MODEL INTERCOMPARISON PROJECT; SAN-ANDREAS FAULT; SOUTHERN-CALIFORNIA; EVOLUTION; FIELD; PREDICTION AB Observations indicate that earthquake faults occur in topologically complex, multi-scale networks driven by plate tectonic forces. We present realistic numerical simulations, involving data-mining, pattern recognition, theoretical analyses and ensemble forecasting techniques, to understand how the observable space-time earthquake patterns are related to the fundamentally inaccessible and unobservable dynamics. Numerical simulations can also help us to understand how the different scales involved in earthquake physics interact and influence the resulting dynamics. Our simulations indicate that elastic interactions (stress transfer) combined with the nonlinearity in the frictional failure threshold law lead to the self-organization of the statistical dynamics, producing 1) statistical distributions for magnitudes and frequencies of earthquakes that have characteristics similar to those possessed by the Gutenberg-Richter magnitude-frequency distributions observed in nature; and 2) clear examples of stress transfer among fault activity described by stress shadows, in which an earthquake oil one group of faults reduces the Coulomb failure stress oil other faults, thereby delaying activity oil those faults. In this paper, we describe the Current state of modeling and simulation efforts for Virtual California, a model (or all the major active strike slip faults in California. Noting that the Working Group oil California Earthquake Probabilities (WGCEP) uses statistical distributions to produce earthquake forecast probabilities, we demonstrate that Virtual California provides a powerful tool for testing the applicability and reliability of the WGCEP statistical methods. Furthermore, we show how the simulations call be used to develop statistical earthquake forecasting techniques that are complementary to the methods used by the WGCEP, but improve upon those methods in a number of important ways. In doing so, we distinguish between the "official", forecasts of the WGCEP, and the "research-quality" forecasts that we discuss here. Finally, we provide a brief discussion of future problems and issues related to the development of ensemble earthquake hazard estimation and forecasting techniques. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Calif Davis, Ctr Computat Sci & Engn, Davis, CA 95616 USA. Harvey Mudd Coll, Dept Phys, Claremont, CA 91711 USA. CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91125 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Univ Calif Davis, Dept Geol, Davis, CA 95616 USA. Univ Calif Irvine, Dept Environm Hlth Safety & Policy, Irvine, CA 92697 USA. RP Rundle, JB (reprint author), Univ Calif Davis, Ctr Computat Sci & Engn, 1 Shields Ave, Davis, CA 95616 USA. EM jbrundle@ucdavis.edu; prundle@ucdavis.edu; andrea.donnellan@jpl.nasa.gov; klein@buphy.bu.edu; gleb@cse.ucdavis.edu; turcotte@geology.ucdavis.edu; lgrant@uci.edu RI Ludwig, Lisa Grant/G-6442-2012 OI Ludwig, Lisa Grant/0000-0001-6538-8067 NR 47 TC 19 Z9 19 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-1951 J9 TECTONOPHYSICS JI Tectonophysics PD FEB 2 PY 2006 VL 413 IS 1-2 BP 109 EP 125 DI 10.1016/j.tecto.2005.10.031 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 011MU UT WOS:000235273200012 ER PT J AU Beutner, T Rumsey, C AF Beutner, T Rumsey, C TI Introduction: Computational fluid dynamics validation for synthetic jets SO AIAA JOURNAL LA English DT Editorial Material C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Beutner, T (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 0 TC 0 Z9 0 U1 5 U2 45 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 FEB PY 2006 VL 44 IS 2 BP 193 EP 193 PG 1 WC Engineering, Aerospace SC Engineering GA 018TR UT WOS:000235788200001 ER PT J AU Yamaleev, NK Carpenter, MH AF Yamaleev, NK Carpenter, MH TI Quasi-one-dimensional model for realistic three-dimensional synthetic jet actuators SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT 2nd AIAA Flow Control Conference CY JUL, 2004 CL Portland, OR SP Amer Inst Aeronaut & Astronaut ID SIMULATION; BOUNDARY AB A systematic methodology for approximating realistic three-dimensional synthetic jet actuators by using a reduced-order model based on the time-dependent compressible quasi-one-dimensional Euler equations is presented. The following major questions are addressed: 1) which three-dimensional actuator geometries are amenable to the quasi-one-dimensional approximation; 2) which three-dimensional actuator parameters should be retained in the quasi-one-dimensional model; 3) which actuator flow regions are essentially multidimensional and are not candidates for reduced-order modeling; and 4) which geometrical features practically do not contribute to the fidelity of the actuator solution. Constraints that should be imposed on the actuator geometry and the flow parameters are discussed. The accuracy of the quasi-one-dimensional model is validated by comparing the numerical results with experimental data and full time-dependent Navier-Stokes simulation of the same realistic actuator. C1 N Carolina Agr & Tech State Univ, Dept Math, Greensboro, NC 27411 USA. NASA Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA. RP Yamaleev, NK (reprint author), N Carolina Agr & Tech State Univ, Dept Math, Greensboro, NC 27411 USA. EM nkyamale@ncat.edu NR 14 TC 11 Z9 11 U1 0 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 FEB PY 2006 VL 44 IS 2 BP 208 EP 216 DI 10.2514/1.14495 PG 9 WC Engineering, Aerospace SC Engineering GA 018TR UT WOS:000235788200003 ER PT J AU Vatsa, VN Turkel, E AF Vatsa, VN Turkel, E TI Simulation of synthetic jets using unsteady Reynolds-averaged Navier-Stokes equations SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 2nd Flow Control Conference CY JUN 28-JUL 01, 2004 CL Portland, OR SP Amer Inst Aeronaut & Astronaut ID VISCOSITY AB An unsteady Reynolds-averaged Navier-Stokes solver is applied for the simulation of a synthetic (zero net mass flow) jet created by a single diaphragm piezoelectric actuator in quiescent air. This configuration was designated as case 1 for the Computational Fluid Dynamics Validation 2004 (CFDVAL2004) workshop held at Williamsburg, Virginia, in March 2004. Time-averaged and instantaneous (phase-averaged) data for this case were obtained at NASA Langley Research Center, using multiple measurement techniques. Computational results from two-dimensional simulations with one-equation Spalart-Allmaras and two-equation Menter's turbulence models are presented along with the experimental data. The effect of grid refinement, preconditioning, and time-step variation are also examined. C1 NASA Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA. Tel Aviv Univ, IL-23681 Tel Aviv, Israel. RP NASA Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA. RI Turkel, Eli/F-6297-2011 OI Turkel, Eli/0000-0003-4273-0303 NR 29 TC 16 Z9 16 U1 0 U2 4 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 FEB PY 2006 VL 44 IS 2 BP 217 EP 224 DI 10.2514/1.13535 PG 8 WC Engineering, Aerospace SC Engineering GA 018TR UT WOS:000235788200004 ER PT J AU Hixon, R Golubev, V Mankbadi, RR Scott, JR Sawyer, S Nallasamy, M AF Hixon, R Golubev, V Mankbadi, RR Scott, JR Sawyer, S Nallasamy, M TI Application of a nonlinear computational aeroacoustics code to the gust-airfoil problem SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT 2nd AIAA Flow Control Conference CY JUL, 2004 CL Portland, OR SP Amer Inst Aeronaut & Astronaut ID RUNGE-KUTTA SCHEMES; FINITE-DIFFERENCE; LOW-DISSIPATION; ACOUSTICS; FLOWS; NOISE AB A time-domain solution of the gust-airfoil problem is obtained using a high-accuracy computational aeroacoustics code to solve the nonlinear Euler equations. For computational efficiency, the equations are cast in chain-rule curvilinear form, and a structured multiblock solver is used on a distributed-memory parallel computer cluster. To fully investigate the performance of this solver, a test matrix of benchmark problems is computed (two airfoil geometries and four gust-reduced frequencies). These results are compared to benchmark solutions both on the airfoil surface and in the flow domain. C1 Univ Toledo, Mech Ind & Mfg Engn Dept, Toledo, OH 43606 USA. Embry Riddle Aeronaut Univ, Aerosp Engn Dept, Daytona Beach, FL 32114 USA. NASA, Lewis Res Ctr, Coll Engn, Cleveland, OH 44135 USA. Univ Akron, Acoust Branch, Akron, OH 44325 USA. QSS Grp Inc, Mech Engn Dept, Cleveland, OH 44135 USA. RP Hixon, R (reprint author), Univ Toledo, Mech Ind & Mfg Engn Dept, 2801 W Bancroft St, Toledo, OH 43606 USA. NR 33 TC 16 Z9 16 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 FEB PY 2006 VL 44 IS 2 BP 323 EP 328 DI 10.2514/1.3478 PG 6 WC Engineering, Aerospace SC Engineering GA 018TR UT WOS:000235788200015 ER PT J AU Stewart, JM Medow, MS Glover, JL Montgomery, LD AF Stewart, JM Medow, MS Glover, JL Montgomery, LD TI Persistent splanchnic hyperemia during upright tilt in postural tachycardia syndrome SO AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY LA English DT Article DE vasoconstriction; blood volume; autonomic; orthostatic intolerance ID THORACIC BLOOD-VOLUME; VALSALVA MANEUVER; MESENTERIC-ARTERY; SYNDROME POTS; ORTHOSTATIC INTOLERANCE; MENSTRUAL-CYCLE; NITRIC-OXIDE; FLOW; SYSTEM; RESISTANCE AB Previous investigations have allowed for stratification of patients with postural tachycardia syndrome ( POTS) on the basis of peripheral blood flow. One such subset, comprising "normal-flow POTS" patients, is characterized by normal peripheral resistance and blood volume in the supine position but thoracic hypovolemia and splanchnic blood pooling in the upright position. We studied 32 consecutive 14- to 22-yr-old POTS patients comprising 13 with low-flow POTS, 14 with normal-flow POTS, and 5 with high-flow POTS and 12 comparably aged healthy volunteers. We measured changes in impedance plethysmographic ( IPG) indexes of blood volume and blood flow within thoracic, splanchnic, pelvic ( upper leg), and lower leg regional circulations in the supine posture and during incremental tilt to 20, 35, and 70. We validated IPG measures of thoracic and splanchnic blood flow against indocyanine green dye-dilution measurements. We validated IPG leg blood flow against venous occlusion plethysmography. Control subjects developed progressive vasoconstriction with incremental tilt. Splanchnic blood flow was increased in the supine position in normal-flow POTS, despite marked peripheral vasoconstriction, and did not change during incremental tilt, producing progressive splanchnic hypervolemia. Absolute hypovolemia was present in low-flow POTS, all supine flows and volumes were reduced, there was no vasoconstriction with tilt in all segments, and segmental volumes tended to increase uniformly throughout tilt. Lower body ( pelvic and leg) flows were increased in high-flow POTS at all angles, with consequent lower body hypervolemia during tilt. Our main finding is selective and maintained orthostatic splanchnic vasodilation in normal-flow POTS, despite marked peripheral vasoconstriction in these same patients. Local splanchnic vasoregulatory factors may counteract vasoconstriction and venoconstriction in these patients. Lower body vasoconstriction in high-flow POTS was abnormal, and vasoconstriction in low-flow POTS was sustained at initially elevated supine levels. C1 New York Med Coll, Div Res, Hawthorne, NY 10532 USA. New York Med Coll, Hypotens Lab, Hawthorne, NY 10532 USA. New York Med Coll, Dept Pediat, Valhalla, NY 10595 USA. New York Med Coll, Dept Physiol, Valhalla, NY 10595 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Stewart, JM (reprint author), New York Med Coll, Div Res, Suite 3050,19 Bradhurst Ave, Hawthorne, NY 10532 USA. EM stewart@nymc.edu FU NHLBI NIH HHS [1R01 HL-074873, 1R01 HL-66007, R01 HL066007, R01 HL074873]; NINDS NIH HHS [R21 NS094644] NR 39 TC 40 Z9 41 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6135 J9 AM J PHYSIOL-HEART C JI Am. J. Physiol.-Heart Circul. Physiol. PD FEB PY 2006 VL 290 IS 2 BP H665 EP H673 DI 10.1152/ajpheart.00784.2005 PG 9 WC Cardiac & Cardiovascular Systems; Physiology; Peripheral Vascular Disease SC Cardiovascular System & Cardiology; Physiology GA 001KC UT WOS:000234531000024 PM 16143646 ER PT J AU Karner, JM Sutton, SR Papike, JJ Shearer, CK Jones, JH Newville, M AF Karner, JM Sutton, SR Papike, JJ Shearer, CK Jones, JH Newville, M TI Application of a new vanadium valence oxybarometer to basaltic glasses from the Earth, Moon, and Mars SO AMERICAN MINERALOGIST LA English DT Article DE oxygen fugacity; planetary basalts; vanadium; oxidation state; Mars; XANES ID COMPARATIVE PLANETARY MINERALOGY; EDGE ABSORPTION-SPECTRA; SYNCHROTRON MICRO-XANES; IRON OXIDATION-STATES; X-RAY-ABSORPTION; OXYGEN FUGACITY; UPPER-MANTLE; EXPERIMENTAL PETROLOGY; MARTIAN BASALTS; REDOX STATES AB The redox states of volcanic and impact melts from the Earth, Moon, and Mars have been estimated from the valence state of V in basaltic glasses (Sutton et al. 2005). The V valence has been determined using synchrotron micro X-ray absorption near-edge structure spectroscopy (XANES) (Sutton et al. 2005), which allows for in situ measurements on samples with a micrometer spatial resolution and similar to 100 ppm elemental sensitivity. Here, we interpret those results for the natural samples and compare them to the literature. The results show that terrestrial melts are dominated by V4+, lunar samples by V3+, with Martian melts a mixture of both V3+ and V4+. The f(O2) estimates derived from the V valence are consistent with those determined by other proven methods, whereby terrestrial basalts experience f(O2) conditions within 1 or 2 log units of the QFM buffer, lunar basalts equilibrate at 1 to 2 log units below the IW buffer, and Martian basalts fall somewhere between the QFM and IW buffer. The results illustrate the usefulness of this technique; i.e., a robust oxybarometer covering over six orders of magnitude, applicable to samples that record f(O2) conditions from reduced extraterrestrial bodies to the oxidized Earth. C1 Univ New Mexico, Dept Earth & Planetary Sci, Inst Meteorit, Albuquerque, NM 87131 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. Univ Chicago, Consortium Adv Radiat Sources, Chicago, IL 60637 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Karner, JM (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, Inst Meteorit, Albuquerque, NM 87131 USA. EM jkarner@unm.edu NR 64 TC 26 Z9 27 U1 2 U2 12 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD FEB-MAR PY 2006 VL 91 IS 2-3 BP 270 EP 277 DI 10.2138/am.2006.1830 PG 8 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 014IB UT WOS:000235472000005 ER PT J AU Kuhlman, KR Fusco, WG La Duc, MT Allenbach, LB Ball, CL Kuhlman, GM Anderson, RC Erickson, IK Stuecker, T Benardini, J Strap, JL Crawford, RL AF Kuhlman, KR Fusco, WG La Duc, MT Allenbach, LB Ball, CL Kuhlman, GM Anderson, RC Erickson, IK Stuecker, T Benardini, J Strap, JL Crawford, RL TI Diversity of microorganisms within rock varnish in the Whipple Mountains, California SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID DESERT VARNISH; MOLECULAR CHARACTERIZATION; RADIOCARBON MEASUREMENTS; MICROCOLONIAL FUNGI; SOIL BACTERIA; MOJAVE DESERT; MANGANESE; ORIGIN; COMMUNITY; SURFACES AB Rock varnish from Arizona's Whipple Mountains harbors a microbial community containing about 10(8) microorganisms g(-1) of varnish. Analyses of varnish phospholipid fatty acids and rRNA gene libraries reveal a community comprised of mostly Proteobacteria but also including Actinobacteria, eukaryota, and a few members of the Archaea. Rock varnish represents a significant niche for microbial colonization. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Idaho, Environm Biotechnol Inst, Moscow, ID 83844 USA. Univ Idaho, Dept Biol Sci, Moscow, ID 83844 USA. RP Kuhlman, KR (reprint author), Planetary Sci Inst, 1700 E Fort Lowell Rd,Suite 106, Tucson, AZ 85719 USA. EM kim@psi.edu RI Strap, Janice/H-2395-2012 NR 95 TC 34 Z9 37 U1 1 U2 12 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 FEB PY 2006 VL 72 IS 2 BP 1708 EP 1715 DI 10.1128/AEM.72.2.1708-1715.2006 PG 8 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 012QC UT WOS:000235353100098 PM 16461735 ER PT J AU Schopf, JW Tripathi, AB Kudryavtsev, AB AF Schopf, JW Tripathi, AB Kudryavtsev, AB TI Three-dimensional confocal optical imagery of Precambrian microscopic organisms SO ASTROBIOLOGY LA English DT Article DE confocal laser scanning microscopy; three-dimensional optical imagery; Precambrian microfossils ID LASER-SCANNING MICROSCOPY; BLUE-GREEN ALGA; RAMAN IMAGERY; WESTERN-AUSTRALIA; SOVIET-UNION; FOSSILS; MICROFOSSILS; MICROORGANISMS; GUNFLINT; CHERT AB A major difficulty that has long hindered studies of organic-walled Precambrian microbes in petrographic thin sections is the accurate documentation of their three-dimensional morphology. To address this need, we here demonstrate the use of confocal laser scanning microscopy. This technique, both non-intrusive and non-destructive, can provide data by which to objectively characterize, in situ and at submicron-scale resolution, the cellular and organismal morphology of permineralized (petrified) microorganisms. Application of this technique can provide information in three dimensions about the morphology, taphonomy, and fidelity of preservation of such fossils at a spatial resolution unavailable by any other means. C1 Univ Calif Los Angeles, Ctr Study Evolut & Origin Life, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90024 USA. Univ Calif Los Angeles, Inst Mol Biol, Los Angeles, CA 90024 USA. Univ Calif Los Angeles, NASA, Astrobiol Inst, Los Angeles, CA USA. RP Schopf, JW (reprint author), Univ Calif Los Angeles, Ctr Study Evolut & Origin Life, Inst Geophys & Planetary Phys, Geol Bldg, Los Angeles, CA 90095 USA. EM Schopf@ess.ucla.edu NR 48 TC 35 Z9 38 U1 3 U2 16 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 FEB PY 2006 VL 6 IS 1 BP 1 EP 16 DI 10.1089/ast.2006.6.1 PG 16 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 025DR UT WOS:000236246000001 PM 16551223 ER PT J AU Tinetti, G Meadows, VS Crisp, D Fong, W Fishbein, E Turnbull, M Bibring, JP AF Tinetti, G Meadows, VS Crisp, D Fong, W Fishbein, E Turnbull, M Bibring, JP TI Detectability of planetary characteristics in disk-averaged spectra. I: The Earth model SO ASTROBIOLOGY LA English DT Article DE radiative transfer; remote sensing; spectroscopy; Earth; extrasolar terrestrial planets; planetary science ID ALBEDO; REFLECTANCE; ULTRAVIOLET; ABSORPTION; SCATTERING; SUNLIGHT; MARS; SKY AB Over the next 2 decades, NASA and ESA are planning a series of space-based observatories to detect and characterize extrasolar planets. This first generation of observatories will not be able to spatially resolve the terrestrial planets detected. Instead, these planets will be characterized by disk-averaged spectroscopy. To assess the detectability of planetary characteristics in disk-averaged spectra, we have developed a spatially and spectrally resolved model of the Earth. This model uses atmospheric and surface properties from existing observations and modeling studies as input, and generates spatially resolved high-resolution synthetic spectra using the Spectral Mapping Atmospheric Radiative Transfer model. Synthetic spectra were generated for a variety of conditions, including cloud coverage, illumination fraction, and viewing angle geometry, over a wavelength range extending from the ultraviolet to the far-infrared. Here we describe the model and validate it against disk-averaged visible to infrared observations of the Earth taken by the Mars Global Surveyor Thermal Emission Spectrometer, the ESA Mars Express Omega instrument, and ground-based observations of earthshine reflected from the unilluminated portion of the Moon. The comparison between the data and model indicates that several atmospheric species can be identified in disk-averaged Earth spectra, and potentially detected depending on the wavelength range and resolving power of the instrument. At visible wavelengths (0.4-0.9 mu m) O-3, H2O, O-2, and oxygen dimer [(O-2)(2)] are clearly apparent. In the mid-infrared (5-20 mu m) CO2, O-3, and H2O are present. CH4, N2O, CO2, O-3, and H2O are visible in the near-infrared (1-5 mu m). A comprehensive three-dimensional model of the Earth is needed to produce a good fit with the observations. C1 NASA, Astrobiol Inst, Pasadena, CA USA. CNR, Pasadena, CA USA. Jet Prop Lab, Pasadena, CA USA. Spitzer Sci Ctr, Pasadena, CA USA. CALTECH, Pasadena, CA 91125 USA. Carnegie Inst, Washington, DC USA. Inst Astrophys Spatiale, Orsay, France. RP Tinetti, G (reprint author), Inst Astrophys, Sect Planetes Extra Solaires, 98bis Bld Arago, F-75014 Paris, France. EM tinetti@iap.fr OI Tinetti, Giovanna/0000-0001-6058-6654 NR 40 TC 68 Z9 68 U1 1 U2 13 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 FEB PY 2006 VL 6 IS 1 BP 34 EP 47 DI 10.1089/ast.2006.6.34 PG 14 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 025DR UT WOS:000236246000003 PM 16551225 ER PT J AU Sohn, ST O'Connell, RW Kundu, A Landsman, WB Burstein, D Bohlin, RC Frogel, JA Rose, JA AF Sohn, ST O'Connell, RW Kundu, A Landsman, WB Burstein, D Bohlin, RC Frogel, JA Rose, JA TI Hot populations in M87 globular clusters SO ASTRONOMICAL JOURNAL LA English DT Review DE galaxies : individual (M87); galaxies : star clusters; globular clusters : general; ultraviolet : galaxies ID EARLY-TYPE GALAXIES; OLD STELLAR POPULATIONS; FAR-ULTRAVIOLET EMISSION; HORIZONTAL-BRANCH STARS; HUBBLE-SPACE-TELESCOPE; ELLIPTIC GALAXIES; METAL-RICH; INTEGRATED SPECTRA; EVOLUTION-EXPLORER; BLUE STRAGGLERS AB To explore the production of UV-bright stars in old, metal-rich populations like those in elliptical galaxies, we have obtained Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph far- and near-UV photometry of globular clusters (GCs) in four fields in the giant elliptical (gE) galaxy M87. To a limit of m(FUV) similar to 25 we detect a total of 66 GCs in common with the deep HST optical-band study of Kundu et al. Despite strong overlap in V- and I-band properties, the M87 GCs have UV-optical properties that are distinct from clusters in the Milky Way and in M31. M87 clusters, especially metal-poor ones, produce larger hot horizontal-branch populations than do Milky Way analogs. In color plots including the near-UV band, the M87 clusters appear to represent an extension of the Milky Way sequence. Cluster mass is probably not a factor in these distinctions. The most metal-rich M87 GCs in our sample are near solar metallicity and overlap the local E galaxy sample in estimated Mg-2 line indices. Nonetheless, the clusters produce much more UV light at a given Mg-2, being up to 1 mag bluer than any gE galaxy in (FUV - V) color. The M87 GCs do not appear to represent a transition between Milky Way - type clusters and E galaxies. The differences are in the correct sense if the clusters are significantly older than the E galaxies. Comparisons with Galactic open clusters indicate that the hot stars lie on the extreme horizontal branch, rather than being blue stragglers, and that the extreme horizontal branch becomes well populated for ages >= 5 Gyr. Existing model grids for clusters do not match the observations well, due to poorly understood giant branch mass loss or perhaps high helium abundances. We find that 41 of our UV detections have no optical-band counterparts. Most appear to be UV-bright background galaxies seen through M87. Eleven near-UV variable sources detected at only one epoch in the central field are probably classical novae. Two recurrent variable sources have no obvious explanation but could be related to activity in the relativistic jet. C1 Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. Korea Astron & Space Sci Inst, Taejon 305348, South Korea. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Assoc Univ Res Astron Inc, Washington, DC 20005 USA. Carnegie Inst Sci, Dept Terr Magnetism, Washington, DC 20015 USA. Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RP Univ Virginia, Dept Astron, POB 3818, Charlottesville, VA 22903 USA. EM tonysohn@kasi.re.kr; rwo@virginia.edu NR 103 TC 39 Z9 39 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 EI 1538-3881 J9 ASTRON J JI Astron. J. PD FEB PY 2006 VL 131 IS 2 BP 866 EP 888 DI 10.1086/499039 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 010RX UT WOS:000235214500018 ER PT J AU Stockdale, CJ Maddox, LA Cowan, JJ Prestwich, A Kilgard, R Immler, S AF Stockdale, CJ Maddox, LA Cowan, JJ Prestwich, A Kilgard, R Immler, S TI A radio and X-ray study of historical supernovae in M83 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : individual ( M83); radio continuum : galaxies; supernovae : general; supernovae : individual (SN 1923A, SN1945B, SN1950B, SN 1957D, SN 1968L, SN1983N) ID HUBBLE-SPACE-TELESCOPE; EXTRAGALACTIC DISTANCE SCALE; RAPID PRESUPERNOVA EVOLUTION; KEY PROJECT; SOURCE POPULATION; LIGHT CURVES; I SUPERNOVA; SN 1978K; NGC 1313; EMISSION AB We report the results of 15 years of radio observations of the six historical supernovae (SNe) in M83 using the Very Large Array. We note the near-linear decline in radio emission from SN 1957D, a Type II SN, which remains a nonthermal radio emitter. The measured flux densities from SNe 1923A and 1950B have flattened as they begin to fade below detectable limits; they are also Type II SNe. The luminosities for these three SNe are comparable with the radio luminosities of other decades-old SNe at similar epochs. SNe 1945B, 1968L, and 1983N were not detected in the most recent observations, and these nondetections are consistent with previous studies. We report the X-ray nondetections of all six historical SNe using the Chandra X-Ray Observatory, consistent with previous X-ray searches of other decades-old SNe and low inferred mass-loss rates of the progenitors [. M approximate to (10(-8) M-circle dot yr(-1)) (nu(w)/10 km s(-1))]. C1 Marquette Univ, Dept Phys, Milwaukee, WI 53201 USA. Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Explorat Univ Div, Greenbelt, MD 20771 USA. RP Stockdale, CJ (reprint author), Marquette Univ, Dept Phys, POB 1881, Milwaukee, WI 53201 USA. EM christopher.stockdale@marquette.edu; maddox@nhn.ou.edu; cowan@nhn.ou.edu; aprestwich@cfa.harvard.edu; rkilgard@cfa.harvard.edu; immler@milkyway.gsfc.nasa.gov NR 47 TC 13 Z9 13 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 FEB PY 2006 VL 131 IS 2 BP 889 EP 894 DI 10.1086/499401 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 010RX UT WOS:000235214500019 ER PT J AU Skrutskie, MF Cutri, RM Stiening, R Weinberg, MD Schneider, S Carpenter, JM Beichman, C Capps, R Chester, T Elias, J Huchra, J Liebert, J Lonsdale, C Monet, DG Price, S Seitzer, P Jarrett, T Kirkpatrick, JD Gizis, JE Howard, E Evans, T Fowler, J Fullmer, L Hurt, R Light, R Kopan, EL Marsh, KA McCallon, HL Tam, R Van Dyk, S Wheelock, S AF Skrutskie, MF Cutri, RM Stiening, R Weinberg, MD Schneider, S Carpenter, JM Beichman, C Capps, R Chester, T Elias, J Huchra, J Liebert, J Lonsdale, C Monet, DG Price, S Seitzer, P Jarrett, T Kirkpatrick, JD Gizis, JE Howard, E Evans, T Fowler, J Fullmer, L Hurt, R Light, R Kopan, EL Marsh, KA McCallon, HL Tam, R Van Dyk, S Wheelock, S TI The Two Micron All Sky Survey (2MASS) SO ASTRONOMICAL JOURNAL LA English DT Article DE catalogs; infrared : general; surveys ID CATALOG; CALIBRATION; SYSTEM AB Between 1997 June and 2001 February the Two Micron All Sky Survey (2MASS) collected 25.4 Tbytes of raw imaging data covering 99.998% of the celestial sphere in the near-infrared J ( 1.25 mu m), H(1.65 mu m), and K-s(2.16 mu m) bandpasses. Observations were conducted from two dedicated 1.3 m diameter telescopes located at Mount Hopkins, Arizona, and Cerro Tololo, Chile. The 7.8 s of integration time accumulated for each point on the sky and strict quality control yielded a 10 sigma point-source detection level of better than 15.8, 15.1, and 14.3 mag at the J, H, and Ks bands, respectively, for virtually the entire sky. Bright source extractions have 1 sigma photometric uncertainty of < 0.03 mag and astrometric accuracy of order 100 mas. Calibration offsets between any two points in the sky are < 0.02 mag. The 2MASS All-Sky Data Release includes 4.1 million compressed FITS images covering the entire sky, 471 million source extractions in a Point Source Catalog, and 1.6 million objects identified as extended in an Extended Source Catalog. C1 Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Dept Astron, Tucson, AZ 85721 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. USAF, Res Lab, Bedford, MA 01731 USA. Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA. RP Univ Virginia, Dept Astron, POB 3818, Charlottesville, VA 22903 USA. OI Weinberg, Martin/0000-0003-2660-2889; Gizis, John/0000-0002-8916-1972; Van Dyk, Schuyler/0000-0001-9038-9950 NR 20 TC 4913 Z9 4938 U1 11 U2 52 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 EI 1538-3881 J9 ASTRON J JI Astron. J. PD FEB PY 2006 VL 131 IS 2 BP 1163 EP 1183 DI 10.1086/498708 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 010RX UT WOS:000235214500046 ER PT J AU Vreeswijk, PM Smette, A Fruchter, AS Palazzi, E Rol, E Wijers, RAMJ Kouveliotou, C Kaper, L Pian, E Masetti, N Frontera, F Hjorth, J Gorosabel, J Piro, L Fynbo, JPU Jakobsson, P Watson, D O'Brien, PT Ledoux, C AF Vreeswijk, PM Smette, A Fruchter, AS Palazzi, E Rol, E Wijers, RAMJ Kouveliotou, C Kaper, L Pian, E Masetti, N Frontera, F Hjorth, J Gorosabel, J Piro, L Fynbo, JPU Jakobsson, P Watson, D O'Brien, PT Ledoux, C TI Low-resolution VLT spectroscopy of GRBs 991216, 011211 and 021211 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : bursts; galaxies : abundances; galaxies : distances and redshifts; galaxies : quasars : absorption lines ID GAMMA-RAY BURST; EARLY OPTICAL-EMISSION; HIGH COLUMN DENSITY; 28 FEBRUARY 1997; HOST GALAXY; ABSORPTION SYSTEMS; INTERSTELLAR DUST; STAR-FORMATION; GRB 991216; ERROR BOX AB We present low-resolution VLT spectroscopy of the afterglow of the gamma-ray bursts (GRBs) 991216, 011211 and 021211. Our spectrum of GRB 991216 is the only optical spectrum for this afterglow. It shows two probable absorption systems at z = 0.80 and z = 1.02, where the highest redshift most likely reflects the distance to the host galaxy. A third system may be detected at z = 0.77. HST imaging of the field, obtained 4 months after the burst, has resulted in the detection of two amorphous regions of emission, one at the projected afterglow position, and the other 0.''6 away. The spectrum shows a depression in flux in between 4000 angstrom and 5500 angstrom. This could be the result of a 2175 angstrom-type extinction feature in the host of GRB 991216, but at a rather red wavelength of 2360 angstrom. If this interpretation is correct, it is the first time the extinction feature is seen in a GRB afterglow spectrum. It is centered at a wavelength similar to that of the ultra-violet (UV) bumps inferred from observations of a few UV-strong, hydrogen-poor stars in the Galaxy. All significant absorption lines (except for one) detected in the spectrum of GRB 011211 are identified with lines originating in a single absorption system at z = 2.142 +/- 0.002, the redshift of the GRB 011211 host galaxy. We also detect the Ly alpha absorption line in the host, to which we fit a neutral hydrogen column density of log N( H I) = 20.4 +/- 0.2, which indicates that it is a damped Lya system. Using a curve-of-growth analysis, we estimate the Si, Fe and Al metallicity at the GRB 011211 redshift to be [Si/H] = -0.9(-0.4)(+0.6), [Fe/H] = -1.3 +/- 0.3, and [Al/H] = -1.0(-0.3)(+0.5) . For GRB 021211, we detect a single emission line in a spectrum obtained tens of days after the burst, which we identify as [O II] lambda 3727 at z = 1.006. The corresponding unobscured [O II] star-formation rate is 1.4 M-circle dot yr(-1). C1 European So Observ, Santiago 19, Chile. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. Univ Liege, Inst Astrophy & Geophys, B-4000 Liege, Belgium. Space Telescope Sci Inst, Baltimore, MD 21218 USA. INAF, Ist Astrofis Spaziale & Fis Cosm, Sezione Bologna, I-40129 Bologna, Italy. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. NASA, MSFC, Natl Space Sci Technol Ctr, Huntsville, AL 35805 USA. Osserv Astron Trieste, INAF, I-34131 Trieste, Italy. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen 0, Denmark. CSIC, Inst Astrofis Andalucia, Granada 18080, Spain. INAF, Ist Astrofis Spaziale & Fis Cosm, Sezione Roma, I-00133 Rome, Italy. RP Vreeswijk, PM (reprint author), European So Observ, Casilla 19001,Alonso de Cordova 3107, Santiago 19, Chile. EM pvreeswi@eso.org RI PIRO, LUIGI/E-4954-2013; Hjorth, Jens/M-5787-2014; Watson, Darach/E-4521-2015; Jakobsson, Pall/L-9950-2015; Palazzi, Eliana/N-4746-2015; OI PIRO, LUIGI/0000-0003-4159-3984; Hjorth, Jens/0000-0002-4571-2306; Watson, Darach/0000-0002-4465-8264; Jakobsson, Pall/0000-0002-9404-5650; Wijers, Ralph/0000-0002-3101-1808; Palazzi, Eliana/0000-0002-8691-7666; Masetti, Nicola/0000-0001-9487-7740; Pian, Elena/0000-0001-8646-4858 NR 90 TC 46 Z9 46 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 FEB PY 2006 VL 447 IS 1 BP 145 EP 156 DI 10.1051/004-6361:20053795 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 007GS UT WOS:000234957400014 ER PT J AU Verhoelst, T Decin, L Van Malderen, R Hony, S Cami, J Eriksson, K Perrin, G Deroo, P Vandenbussche, B Waters, LBFM AF Verhoelst, T Decin, L Van Malderen, R Hony, S Cami, J Eriksson, K Perrin, G Deroo, P Vandenbussche, B Waters, LBFM TI Amorphous alumina in the extended atmosphere of alpha Orionis SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE techniques : high angular resolution; techniques : spectroscopic; stars : individual : alpha Orionis; stars : atmospheres; stars : supergiants; stars : circumstellar matter ID ASYMPTOTIC GIANT BRANCH; RICH CIRCUMSTELLAR DUST; WATER-VAPOR ENVELOPE; ISO-SWS CALIBRATION; LATE-TYPE STARS; EVOLVED STARS; MIRA VARIABLES; MODEL ATMOSPHERES; INTERFEROMETRIC OBSERVATIONS; MOLECULAR-LAYERS AB In this paper we study the extended atmosphere of the late-type supergiant alpha Orionis. Infrared spectroscopy of red supergiants reveals strong molecular bands, some of which do not originate in the photosphere but in a cooler layer of molecular material above it. Lately, these layers have been spatially resolved by near and mid-IR interferometry. In this paper, we try to reconcile the IR interferometric and ISO-SWS spectroscopic results on a Orionis with a thorough modelling of the photosphere, molecular layer(s) and dust shell. From the ISO and near-IR interferometric observations, we find that a Orionis has only a very low density water layer close above the photosphere. However, mid-IR interferometric observations and a narrow-slit N-band spectrum suggest much larger extra-photospheric opacity close to the photosphere at those wavelengths, even when taking into account the detached dust shell. We argue that this cannot be due to the water layer, and that another source of mid-IR opacity must be present. We show that this opacity source is probably neither molecular nor chromospheric. Rather, we present amorphous alumina (Al2O3) as the best candidate and discuss this hypothesis in the framework of dust-condensation scenarios. C1 Katholieke Univ Leuven, Inst Sterrenkunde, B-3001 Heverlee, Belgium. Observ Paris, LESIA, F-92195 Meudon, France. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Inst Astron & Space Phys, S-75120 Uppsala, Sweden. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. RP Verhoelst, T (reprint author), Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200B, B-3001 Heverlee, Belgium. EM Tijl.Verhoelst@ster.kuleuven.ac.be NR 78 TC 45 Z9 45 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 FEB PY 2006 VL 447 IS 1 BP 311 EP 324 DI 10.1051/0004-6361:20053359 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 007GS UT WOS:000234957400029 ER PT J AU Covino, S Malesani, D Israel, GL D'Avanzo, P Antonelli, LA Chincarini, G Fugazza, D Conciatore, ML Della Valle, M Fiore, F Guetta, D Hurley, K Lazzati, D Stella, L Tagliaferri, G Vietri, M Campana, S Burrows, DN D'Elia, V Filliatre, P Gehrels, N Goldoni, P Melandri, A Mereghetti, S Mirabel, IF Moretti, A Nousek, J O'Brien, PT Pellizza, LJ Perna, R Piranomonte, S Romano, P Zerbi, FM AF Covino, S Malesani, D Israel, GL D'Avanzo, P Antonelli, LA Chincarini, G Fugazza, D Conciatore, ML Della Valle, M Fiore, F Guetta, D Hurley, K Lazzati, D Stella, L Tagliaferri, G Vietri, M Campana, S Burrows, DN D'Elia, V Filliatre, P Gehrels, N Goldoni, P Melandri, A Mereghetti, S Mirabel, IF Moretti, A Nousek, J O'Brien, PT Pellizza, LJ Perna, R Piranomonte, S Romano, P Zerbi, FM TI Optical emission from GRB 050709: a short/hard GRB in a star-forming galaxy SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE radiation mechanisms : non-thermal; gamma rays : bursts; gamma rays : individual GRB 050709 ID GAMMA-RAY BURSTS; SHORT-DURATION; AFTERGLOW; CONSTRAINTS; BRIGHT AB We present optical observations of the shorl/hard gamma-ray burst GRB 050709, the first such event with an identified optical Counterpart. The object is coincident with a weak X-ray Source and is located inside a galaxy at redshift z = 0.1606 +/- 0.0002. Multiband photometry allowed us to study the broad-band spectral energy distribution. Late-time monitoring places strong limits on any supernova simultaneous with the GRB. The host galaxy is not of early type. Spectra show that the dominant stellar population is relatively Young (similar to 1 Gyr), and that ongoing star formation is present at a level of 2-3 L/L. M-. yr(-1). This is at least 2 orders of magnitude larger than that observed in the elliptical hosts of the short GRB 050509B and GRB 050724. This shows that at least some short GRBs originate in a young Population. Short/hard GRB models based oil the merger of a binary degenerate system are compatible with the host galaxy characteristics, although there is still the possibility of a connection between Young stars and at least a fraction of such events. C1 INAF, Osservatorio Astron Brera, I-23807 Merate, LC, Italy. ISAS, SISSA, I-34014 Trieste, Italy. INAF, Osservatorio Astron Roma, I-00040 Rome, Italy. Univ Insubria, Dipartimento Matemat & Fis, I-22100 Como, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. INAF, Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Scuola Normale Super Pisa, I-56126 Pisa, Italy. Penn State Univ, Dept Astron & Astrophys, State Coll, PA 16801 USA. Lab Astroparticule & Cosmol, UMR 7164, F-75231 Paris 05, France. CEA Saclay, Serv Astrophys, DSM, DAPNA, F-91191 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Cagliari, Dipartimento Fis, I-09042 Monserrato, Ca, Italy. INAF IASF Milano G Occhialini, I-20133 Milan, Italy. European So Observ, Santiago 19, Chile. Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. RP INAF, Osservatorio Astron Brera, Via E Bianchi 46, I-23807 Merate, LC, Italy. EM covino@mi.astro.it RI Gehrels, Neil/D-2971-2012; OI Fiore, Fabrizio/0000-0002-4031-4157; Della Valle, Massimo/0000-0003-3142-5020; MEREGHETTI, SANDRO/0000-0003-3259-7801; Israel, GianLuca/0000-0001-5480-6438; Covino, Stefano/0000-0001-9078-5507; Tagliaferri, Gianpiero/0000-0003-0121-0723; D'Elia, Valerio/0000-0002-7320-5862; guetta, dafne/0000-0002-7349-1109; Campana, Sergio/0000-0001-6278-1576; Zerbi, Filippo Maria/0000-0002-9996-973X NR 36 TC 62 Z9 62 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 FEB PY 2006 VL 447 IS 2 BP L5 EP L8 DI 10.1051/0004-6361:200500228 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 015IC UT WOS:000235544100002 ER PT J AU Cappi, M Panessa, F Bassani, L Dadina, M DiCocco, G Comastri, A Della Ceca, R Filippenko, AV Gianotti, F Ho, LC Malaguti, G Mulchaey, JS Palumbo, GGC Piconcelli, E Sargent, WLW Stephen, J Trifoglio, M Weaver, KA AF Cappi, M Panessa, F Bassani, L Dadina, M DiCocco, G Comastri, A Della Ceca, R Filippenko, AV Gianotti, F Ho, LC Malaguti, G Mulchaey, JS Palumbo, GGC Piconcelli, E Sargent, WLW Stephen, J Trifoglio, M Weaver, KA TI X-ray spectral survey with XMM-Newton of a complete sample of nearby Seyfert galaxies SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE X-rays : galaxies; galaxies : Seyfert; glaxies : active ID ACTIVE GALACTIC NUCLEI; ABSORBING COLUMN DENSITIES; ALPHA EMISSION-LINES; LOW-LUMINOSITY AGN; ASCA OBSERVATIONS; ELLIPTIC GALAXIES; COMPTON-THICK; NO ABSORPTION; CHANDRA; NGC-4395 AB Results obtained from an X-ray spectral survey of nearby Seyfert galaxies using XMM-Newton are reported. The sample was optically selected, well defined, complete in B magnitude, and distance limited: it consists of the nearest (D less than or similar to 22 Mpc) 27 Seyfert galaxies (9 of type 1, 18 of type 2) taken from the Ho et al. (1997a, ApJS, 112, 315) sample. This is one of the largest atlases of hard X-ray spectra of low-luminosity active galaxies ever assembled. All nuclear sources except two Seyfert 2s are detected between 2 and 10 keV, half for the first time ever, and average spectra are obtained for all of them. Nuclear luminosities reach values down to 1038 erg s(-1). The shape of the distribution of X-ray parameters is affected by the presence of Compton-thick objects (greater than or similar to 30% among type 2s). The latter have been identified either directly from their intense FeK line and flat X-ray spectra, or indirectly with flux diagnostic diagrams which use isotropic indicators. After taking into account these highly absorbed sources, we find that (i) the intrinsic X-ray spectral properties ( i. e., spectral shapes and luminosities above 2 keV) are consistent between type 1 and type 2 Seyferts, as expected from "unified models"; (ii) Seyfert galaxies as a whole are distributed fairly continuously over the entire range of N(H), between 1020 and 1025 cm(-2); and (iii) while Seyfert 1s tend to have lower NH and Seyfert 2s tend to have the highest, we find 30% and 10% exceptions, respectively. Overall the sample is of sufficient quality to well represent the average intrinsic X-ray spectral properties of nearby active galactic nuclei, including a proper estimate of the distribution of their absorbing columns. Finally, we conclude that, with the exception of a few cases, the present study agrees with predictions of unified models of Seyfert galaxies, and extends their validity down to very low luminosities. C1 INAF, IASF Sez Bologna, I-40129 Bologna, Italy. Univ Cantabria, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. INAF, Osservatorio Astron Bologna, I-40127 Bologna, Italy. INAF, Osservatorio Astron Brera, I-20121 Milan, Italy. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Carnegie Observ, Pasadena, CA 91101 USA. Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy. RSSD ESA, XMM Newton Sci Operat Ctr, Madrid 28080, Spain. CALTECH, Dept Astron, Pasadena, CA 91125 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Cappi, M (reprint author), INAF, IASF Sez Bologna, Via Gobetti 101, I-40129 Bologna, Italy. EM cappi@bo.iasf.cnr.it RI Cappi, Massimo/F-4813-2015; Trifoglio, Massimo/F-5302-2015; Comastri, Andrea/O-9543-2015; OI Trifoglio, Massimo/0000-0002-2505-3630; Comastri, Andrea/0000-0003-3451-9970; Dadina, Mauro/0000-0002-7858-7564; piconcelli, enrico/0000-0001-9095-2782; Gianotti, Fulvio/0000-0003-4666-119X; Cappi, Massimo/0000-0001-6966-8920; Della Ceca, Roberto/0000-0001-7551-2252; Malaguti, Giuseppe/0000-0001-9872-3378; Bassani, Loredana/0000-0003-4858-6963; Panessa, Francesca/0000-0003-0543-3617 NR 97 TC 155 Z9 155 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 FEB PY 2006 VL 446 IS 2 BP 459 EP U26 DI 10.1051/0004-6361:20053893 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 002ZP UT WOS:000234651700010 ER PT J AU Veronig, AM Karlicky, M Vrsnak, B Temmer, M Magdalenic, J Dennis, BR Otruba, W Potzi, A AF Veronig, AM Karlicky, M Vrsnak, B Temmer, M Magdalenic, J Dennis, BR Otruba, W Potzi, A TI X-ray sources and magnetic reconnection in the X3.9 flare of 2003 November 3 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : flares; Sun : X-rays, gamma rays ID SOLAR-FLARE; ENERGY-RELEASE; JULY 23; PARTICLE-ACCELERATION; CURRENT SHEETS; RHESSI; EMISSION; MOTIONS; SPECTRA; IMAGER AB Context. Recent RHESSI observations indicate an apparent altitude decrease of flare X-ray loop-top ( LT) sources before changing to the commonly observed upward growth of the flare loop system. Aims. We performed a detailed study of the LT altitude decrease for one well observed flare in order to find further hints on the physics of this phenomenon and how it is related to the magnetic reconnection process in solar flares. Methods. RHESSI X-ray source motions in the 2003 November 3, X3.9 flare are studied together with complementary data from SXI, EIT, and Kanzelhohe Ha. We particularly concentrate on the apparent altitude decrease of the RHESSI X-ray LT source early in the flare and combine kinematical and X-ray spectral analysis. Furthermore, we present simulations from a magnetic collapsing trap model embedded in a standard 2-D magnetic reconnection model of solar flares. Results. We find that at higher photon energies the LT source is located at higher altitudes and shows higher downward velocities than at lower energies. The mean downward velocities range from 14 km s(-1) in the RHESSI 10-15 keV energy band to 45 km s(-1) in the 25-30 keV band. For this flare, the LT altitude decrease was also observed by the SXI instrument with a mean speed of 12 km s(-1). RHESSI spectra indicate that during the time of LT altitude decrease the emission of the LT source is thermal bremsstrahlung from a "superhot" plasma with temperatures increasing from 35 MK to 45 MK and densities of the order of 10(10) cm(-3). The temperature does not significantly increase after this early (pre-impulsive superhot LT) phase, whereas the LT densities increase to a peak value of (3-4) x 10(11) cm(-3). Conclusions. Modeling of a collapsing magnetic trap embedded in a standard 2D magnetic reconnection model can reproduce the key observational findings in case that the observed emission is thermal bremsstrahlung from the hot LT plasma. This agrees with the evaluated RHESSI spectra for this flare. C1 Graz Univ, Inst Phys, IGAM, A-8010 Graz, Austria. Acad Sci Czech Republic, Ondrejov Observ, Prague, Czech Republic. Hvar Observ, Fac Geodesy, Zagreb 10000, Croatia. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Graz Univ, Inst Phys, IGAM, Kanzelhohe Solar Observ, A-9521 Treffen, Austria. RP Veronig, AM (reprint author), Graz Univ, Inst Phys, IGAM, Univ Pl 5, A-8010 Graz, Austria. EM asv@igam.uni-graz.at RI Dennis, Brian/C-9511-2012; Veronig, Astrid/B-8422-2009; Karlicky, Marian/G-9023-2014; OI Temmer, Manuela/0000-0003-4867-7558 NR 78 TC 90 Z9 92 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 EI 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD FEB PY 2006 VL 446 IS 2 BP 675 EP 690 DI 10.1051/0004-6361:20053112 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 002ZP UT WOS:000234651700031 ER PT J AU Brown, RH Baines, KH Bellucci, G Buratti, BJ Capaccioni, F Cerroni, P Clark, RN Coradini, A Cruikshank, DP Drossart, P Formisano, V Jaumann, R Langevin, Y Matson, DL McCord, TB Mennella, V Nelson, RM Nicholson, PD Sicardy, B Sotin, C Baugh, N Griffith, CA Hansen, GB Hibbitts, CA Momary, TW Showalter, MR AF Brown, RH Baines, KH Bellucci, G Buratti, BJ Capaccioni, F Cerroni, P Clark, RN Coradini, A Cruikshank, DP Drossart, P Formisano, V Jaumann, R Langevin, Y Matson, DL McCord, TB Mennella, V Nelson, RM Nicholson, PD Sicardy, B Sotin, C Baugh, N Griffith, CA Hansen, GB Hibbitts, CA Momary, TW Showalter, MR TI Observations in the Saturn system during approach and orbital insertion, with Cassini's visual and infrared mapping spectrometer (VIMS) SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE infrared : solar system; planets and satellites : general ID PARTICLE EROSION MECHANISMS; PLANETARY RING-SYSTEMS; BALLISTIC TRANSPORT; WATER-ICE; GALILEAN SATELLITES; IRREGULAR STRUCTURE; B-RING; SPECTROSCOPY; FLUORESCENCE; METHANE AB The Visual and Infrared Mapping Spectrometer observed Phoebe, Iapetus, Titan and Saturn's rings during Cassini's approach and orbital insertion. Phoebe's surface contains water ice, CO2, and ferrous iron. Iapetus contains CO2 and organic materials. Titan's atmosphere shows methane fluorescence, and night-side atmospheric emission that may be CO2 and CH3D. As determined from cloud motions, the winds at altitude 25-30 km in the south polar region of Titan appear to be moving in a prograde direction at velocity similar to 1 m s(-1). Circular albedo features on Titan's surface, seen at 2.02 mu m, may be palimpsests remaining from the rheological adjustment of ancient impact craters. As such, their long-term persistence is of special interest in view of the expected precipitation of liquids and solids from the atmosphere. Saturn's rings have changed little in their radial structure since the Voyager flybys in the early 1980s. Spectral absorption bands tentatively attributed to Fe2+ suggest that iron-bearing silicates are a source of contamination of the C ring and the Cassini Division. C1 Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Ist Fis Spazio Interplanetario, Consiglio Nazl Ric, I-00133 Rome, Italy. Ist Astrofis Spaziale, Consiglio Nazl Ric, I-00133 Rome, Italy. US Geol Survey, Denver Fed Ctr, Lakewood, CO 80225 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Observ Paris, Dept Rech Spatial, F-92125 Meudon, France. Deutsch Zentrum Luft & Raumfahrt, Inst Planetary Explorat, D-12489 Berlin, Germany. Univ Paris, Inst Astrophys Spatiale, F-91405 Orsay, France. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. Osserv Astron Capodimonte, Ist Nazl Astrofis, I-80131 Naples, Italy. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. CNRS, Fac Sci, UMR 6112, Lab Planetol & Geodynam, F-44072 Nantes 03, France. RP Brown, RH (reprint author), Univ Arizona, Dept Planetary Sci, 1629 E Univ Blvd, Tucson, AZ 85721 USA. EM rhb@lpl.arizona.edu RI Hibbitts, Charles/B-7787-2016; OI Hibbitts, Charles/0000-0001-9089-4391; Bellucci, Giancarlo/0000-0003-0867-8679; Cerroni, Priscilla/0000-0003-0239-2741; Capaccioni, Fabrizio/0000-0003-1631-4314 NR 45 TC 38 Z9 38 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 FEB PY 2006 VL 446 IS 2 BP 707 EP 716 DI 10.1051/0004-6361:20053054 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 002ZP UT WOS:000234651700033 ER PT J AU Muterspaugh, MW Lane, BF Konacki, M Burke, BF Colavita, MM Kulkarni, SR Shao, M AF Muterspaugh, MW Lane, BF Konacki, M Burke, BF Colavita, MM Kulkarni, SR Shao, M TI PHASES differential astrometry and the mutual inclination of the V819 Herculis triple star system SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : individual : V819 Herculis; binaries : close; techniques : interferometric; astrometry ID ICCD SPECKLE OBSERVATIONS; PEAK 4-M TELESCOPE; PALOMAR TESTBED INTERFEROMETER; RS-CANUM-VENATICORUM; BINARY STARS; KITT-PEAK; RELATIVE ORIENTATION; HR-6469=V819-HER; CATALOG; ORBITS AB V819 Herculis is a well-studied triple star system consisting of a "wide" pair with 5.5 year period, one component of which is a 2.2-day period eclipsing single-line spectroscopic binary. Differential astrometry measurements from the Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES) are presented and used to determine a relative inclination between the short- and long-period orbits of 23.6 +/- 4.9 degrees. This represents only the sixth unambiguous determination of the mutual inclination of orbits in a hierarchical triple system. This result is combined with those for the other five systems for analysis of the observed distribution of mutual inclinations in nearby triple systems. It is found that this distribution is different than that which one would expect from random orientations with statistical significance at the 94% level; implications for studying the spatial distribution of angular momentum in star forming regions is discussed. C1 MIT, Dept Phys, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. CALTECH, Dept Geol & Planetary Sci, Pasadena, CA 91125 USA. Polish Acad Sci, Nicholas Copernicus Astron Ctr, PL-87100 Torun, Poland. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Div Phys Math & Astron, Pasadena, CA 91109 USA. RP Muterspaugh, MW (reprint author), MIT, Dept Phys, Kavli Inst Astrophys & Space Res, 70 Vassar St, Cambridge, MA 02139 USA. EM matthew1@mit.edu; blane@mit.edu; maciej@gps.caltech.edu RI Konacki, Maciej/A-1220-2007 NR 33 TC 28 Z9 28 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 FEB PY 2006 VL 446 IS 2 BP 723 EP 732 DI 10.1051/0004-6361:20053749 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 002ZP UT WOS:000234651700035 ER PT J AU Guirado, JC Marti-Vidal, I Marcaide, JM Close, LM Algaba, JC Brandner, W Lestrade, JF Jauncey, DL Jones, DL Preston, RA Reynolds, JE AF Guirado, JC Marti-Vidal, I Marcaide, JM Close, LM Algaba, JC Brandner, W Lestrade, JF Jauncey, DL Jones, DL Preston, RA Reynolds, JE TI On the dynamics of the AB Doradus system SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE astrometry; stars : kinematics; stars : binaries : close; stars : late-type; stars : individual : Rst 137 B; stars : individual : AB Dor ID HUBBLE-SPACE-TELESCOPE; EVOLUTIONARY STATUS; HD 36705; MASS; STAR; SPECTROSCOPY; PRECISION; DWARFS; CORONA AB We present an astrometric analysis of the binary systems AB Dor A/AB Dor C and AB Dor Ba/AB Dor Bb. These two systems of well-known late-type stars are gravitationally associated and they constitute the quadruple AB Doradus system. From the astrometric data available at different wavelengths, we report: (i) a determination of the orbit of AB Dor C, the very low mass companion to AB Dor A, which confirms the mass estimate of 0.090 M circle dot reported in previous works; (ii) a measurement of the parallax of AB Dor Ba, which unambiguously confirms the long-suspected physical association between this star and AB Dor A; and (iii) evidence of orbital motion of AB Dor Ba around AB Dor A, which places an upper bound of 0.4 M circle dot on the mass of the pair AB Dor Ba/AB Dor Bb (50% probability). Further astrometric monitoring of the system at all possible wavelengths would determine with extraordinary precision the dynamical mass of its four components. C1 Univ Valencia, Dept Astron & Astrofis, E-46100 Valencia, Spain. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Observ Paris, LERMA, F-75014 Paris, France. Australia Telescope Natl Facil, Epping, NSW 2121, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Guirado, JC (reprint author), Univ Valencia, Dept Astron & Astrofis, E-46100 Valencia, Spain. EM jose.c.guirado@uv.es RI Marti-Vidal, Ivan/A-8799-2017 OI Marti-Vidal, Ivan/0000-0003-3708-9611 NR 23 TC 15 Z9 15 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 FEB PY 2006 VL 446 IS 2 BP 733 EP 738 DI 10.1051/0004-6361:20053757 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 002ZP UT WOS:000234651700036 ER PT J AU Madden, SC Galliano, F Jones, AP Sauvage, M AF Madden, SC Galliano, F Jones, AP Sauvage, M TI ISM properties in low-metallicity environments - I. Mid-infrared spectra of dwarf galaxies SO ASTRONOMY & ASTROPHYSICS LA English DT Review DE galaxies : dwarf; galaxies : starburst; ISM : general; galaxies : ISM ID POLYCYCLIC AROMATIC-HYDROCARBONS; STAR-FORMING GALAXIES; ULTRALUMINOUS INFRARED GALAXIES; MU-M SPECTROPHOTOMETRY; INITIAL MASS FUNCTION; COMPACT HII-REGIONS; KEY PROJECT SAMPLE; ENERGY-DISTRIBUTION; STARBURST GALAXIES; INTERSTELLAR DUST AB We present new ISOCAM mid-infrared spectra of three starbursting nearby dwarf galaxies, NGC 1569, NGC 1140 and II Zw 40 and the 30 Dor region of the LMC and explore the properties of the ISM in low-metallicity environments, also using additional sources from the literature. We analyse the various components of the ISM probed by the mid-infrared observations and compare them with other Galactic and extragalactic objects. The MIR spectra of the low-metallicity starburst sources are dominated by the [Ne III]lambda 15.56 mu m and [SIV]lambda 10.51 mu m lines, as well as a steeply rising dust continuum. PAH bands are generaly faint, both locally and averaged over the full galaxy, in stark contrast to dustier starburst galaxies, where the PAH features are very prominant and even dominate on global scales. The hardness of the modeled interstellar radiation fields for the dwarf galaxies increases as the presence of PAH band emission becomes less pronounced. The [Ne III]/[Ne II] ratios averaged over the full galaxy are strikingly high, often > 10. Thus, the hard radiation fields are pronounced and pervasive. We find a prominent correlation between the PAHs/VSGs and the [Ne III]/[Ne II] ratios for a wide range of objects, including the low metallicity galaxies as well as Galactic H II regions and other metal-rich galaxies. This effect is consistent with the hardness of the interstellar radiation field playing a major role in the destruction of PAHs in the low metallicity ISM. We see a PAHs/VSGs and metallicity correlation, also found by Engelbracht et al. (2005, ApJ, 628, 29) for a larger survey. Combined effects of metallicity and radiation field seem to be playing important roles in the observed behavior of PAHs in the low metallicity systems. C1 CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 USA. Univ Paris 11, Inst Astrophys Spatiale, CNRS, F-91405 Orsay, France. RP CEA Saclay, Serv Astrophys, Orme Merisiers, F-91191 Gif Sur Yvette, France. EM smadden@cea.fr NR 107 TC 181 Z9 180 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 FEB PY 2006 VL 446 IS 3 BP 877 EP 896 DI 10.1051/004-6361:20053890 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 005CX UT WOS:000234801300009 ER PT J AU Kontar, EP MacKinnon, AL Schwartz, RA Brown, JC AF Kontar, EP MacKinnon, AL Schwartz, RA Brown, JC TI Compton backscattered and primary X-rays from solar flares: angle dependent Green's function correction for photospheric albedo SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE sun : flares; X-rays : general; methods : data analysis; techniques : spectroscopic; scattering ID ELECTRON FLUX SPECTRA; ACTIVE GALACTIC NUCLEI; COLD ELECTRONS; RHESSI DATA; GAMMA-RAYS; BREMSSTRAHLUNG; REFLECTION; ABSORPTION; EMISSION AB The observed hard X-ray (HXR) flux spectrum I(is an element of) from solar flares is a combination of primary bremsstrahlung photons I-P(is an element of) with a spectrally modified component from photospheric Compton backscatter of downward primary emission. The latter can be significant, distorting or hiding the true features of the primary spectrum which are key diagnostics for acceleration and propagation of high energy electrons and of their energy budget. For the first time in solar physics, we use a Green's function approach to the backscatter spectral deconvolution problem, constructing a Green's matrix including photoelectric absorption. This approach allows spectrum-independent extraction of the primary spectrum for several HXR flares observed by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). We show that the observed and primary spectra differ very substantially for flares with hard spectra close to the disk centre. We show in particular that the energy dependent photon spectral index gamma(is an element of) = -dlogI/d log is an element of is very different for I-P(is an element of) and for I-P(is an element of) and that inferred mean source electron spectra (F) over bar (E) differ greatly. Even for a forward fitting of a parametric (F) over bar (E) to the data, a clear low-energy cutoff. required to fit I(is an element of) essentially disappears when the fit is to I-P(is an element of) i.e. when albedo correction is included. The self-consistent correction for backscattered photons is thus shown to be crucial in determining the energy spectra of flare accelerated electrons, and hence their total number and energy. C1 Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Univ Glasgow, DACE, Glasgow G3 6NH, Lanark, Scotland. NASA, Goddard Space Flight Ctr, SSAI, Greenbelt, MD 20771 USA. RP Kontar, EP (reprint author), Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. EM eduard@astro.gla.ac.uk; alec@astro.gla.ac.uk; richard.schwartz@gsfc.nasa.gov; john@astro.gla.ac.uk RI Kontar, Eduard/B-7897-2008 OI Kontar, Eduard/0000-0002-8078-0902 NR 40 TC 62 Z9 62 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 FEB PY 2006 VL 446 IS 3 BP 1157 EP 1163 DI 10.1051/0004-6361:20053672 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 005CX UT WOS:000234801300033 ER PT J AU Weisskopf, MC Aldcroft, TL Cameron, RA Gandhi, P Foellmi, C Elsner, RF Patel, SK Wu, K O'Dell, SL AF Weisskopf, MC Aldcroft, TL Cameron, RA Gandhi, P Foellmi, C Elsner, RF Patel, SK Wu, K O'Dell, SL TI The first Chandra field SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; history and philosophy of astronomy; X-rays : general ID ACTIVE GALACTIC NUCLEI; EMISSION-LINE PROPERTIES; X-RAY-EMISSION; FE-II EMISSION; BALMER DECREMENT; PG QUASARS; CATACLYSMIC VARIABLES; PHYSICAL CONDITIONS; CORRELATION SPACE; SEYFERT-GALAXIES AB Before the official first- light images, the Chandra X- Ray Observatory obtained an X- ray image of the field to which its focal plane was first exposed. We describe this historic observation and report our study of the first Chandra field. Chandra's Advanced CCD Imaging Spectrometer ( ACIS) detected 15 X- ray sources, the brightest being dubbed Leon X- 1 to honor the Chandra telescope scientist LeonVan Speybroeck. Based on our analysis of the X- ray data and spectroscopy at the European Southern Observatory ( ESO; La Silla, Chile), we find that LeonX- 1 is a type- 1 ( unobscured) active galactic nucleus ( AGN) at redshift z = 0: 3207. Leon X- 1 exhibits strong Fe (II) emission and a broad- line Balmer decrement that is unusually flat for an AGN. Within the context of the eigenvector- 1 correlation space, these properties suggest that Leon X- 1 may be a massive ( >= 10(9) M (circle dot)) black hole, accreting at a rate approaching its Eddington limit. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. European So Observ, Santiago 19, Chile. Univ Space Res Assoc, Huntsville, AL 35805 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. RP NASA, George C Marshall Space Flight Ctr, NSSTC XD12,3200 Sparkman Dr, Huntsville, AL 35805 USA. OI O'Dell, Stephen/0000-0002-1868-8056 NR 55 TC 4 Z9 4 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 FEB 1 PY 2006 VL 637 IS 2 BP 682 EP 692 DI 10.1086/497907 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SA UT WOS:000235131600011 ER PT J AU Terebey, S Van Buren, D Brundage, M Hancock, T AF Terebey, S Van Buren, D Brundage, M Hancock, T TI The circumstellar structure of the class I protostar TMC-1 (IRAS 04381+2540) from Hubble Space Telescope NICMOS data SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; ISM : jets and outflows; stars : formation; stars : individual (TMC-1, IRAS 04381+2540) ID YOUNG STELLAR OBJECTS; AURIGA MOLECULAR CLOUD; MAIN-SEQUENCE EVOLUTION; INITIAL MASS FUNCTION; TAURUS-AURIGA; STAR-FORMATION; SUBMILLIMETER CONTINUUM; IMAGING POLARIMETRY; ENVELOPES; DISK AB The class I protostar TMC-1 ( IRAS 04381+2540) is oriented favorably for determining the properties of its circumstellar envelope and outflow cavity. Deep, high spatial resolution Hubble Space Telescope (HST) NICMOS images at 1.6 mu m exhibit both a narrow jet and a wide-angle conical outflow cavity. Model images of the scattered-light distribution fit the data well, reproducing the intensity level, cavity width, and observed limb brightening. The best-fit geometry for TMC-1 has a 45 degrees +/- 5 degrees source inclination and an 80 degrees +/- 5 degrees deprojected wind opening angle ( full width). The age, normally a poorly known quantity, is well constrained; the protostar age, i.e., time since the onset of cloud collapse, is 1; 10(5) yr to within a factor of 2. We offer a possible resolution to the well- known luminosity problem. By considering the efficiency of infall onto the protostar, we find that plausible parameters can give an efficiency, and hence accretion luminosity, as low as 10% of the value derived from the collapsing cloud core. The efficiency, together with a luminosity constraint, leads to a mass estimate that ranges from about 0: 1 M-circle dot for high efficiency to 0: 2 M circle dot for low accretion efficiency onto the protostar. Similarly, the estimated mass accretion rate onto the protostar ranges over roughly ( 0: 9 - 1: 4); 10(-6) M-circle dot yr(-1), which is smaller than the (1.6-3.5); 10(-6) M-circle dot yr(-1) infall rate of the cloud. If low efficiency rates are prevalent for protostars, one important consequence is that it will take longer to assemble the central star than the time t = M-in/M-in , a time that assumes all of the infalling material lands on the protostar. C1 Calif State Univ Los Angeles, Dept Phys & Astron, Los Angeles, CA 90032 USA. Jet Prop Lab, Pasadena, CA 91109 USA. Microsoft Corp, Redmond, WA 98052 USA. Anansi Spaceworks, Grandview, TX 76050 USA. RP Calif State Univ Los Angeles, Dept Phys & Astron, 5151 State Univ Dr, Los Angeles, CA 90032 USA. EM sterebe@calstatela.edu; david.vanburen@jpl.nasa.gov NR 39 TC 12 Z9 12 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 FEB 1 PY 2006 VL 637 IS 2 BP 811 EP 822 DI 10.1086/498385 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SA UT WOS:000235131600024 ER PT J AU Kassis, M Adams, JD Campbell, MF Deutsch, LK Hora, JL Jackson, JM Tollestrup, EV AF Kassis, M Adams, JD Campbell, MF Deutsch, LK Hora, JL Jackson, JM Tollestrup, EV TI Mid-infrared emission at photodissociation regions in the Orion Nebula SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; HII regions; infrared : ISM; ISM : individual (Orion Nebula) ID POLYCYCLIC AROMATIC-HYDROCARBONS; INFRARED-EMISSION; SUBMILLIMETER OBSERVATIONS; IONIZATION FRONT; BAR; RESOLUTION; OBJECTS; SPECTROMETER; EXTINCTION; MILLIMETER AB The mid-infrared emission from a photodissociation region (PDR) viewed edge-on in the Orion Nebula is examined through 8.7-20.6 mu m images and 8 - 13 mu m spectra. The polycyclic aromatic hydrocarbon (PAH) emission is located between the edges of H II regions and layers of [ C I] emission, agreeing with PDR theory. Using a simple model, the spatial variations in the emission from PAHs detected at 8.6, 11.2, and 12.7 mu m are demonstrated to be directly proportional to the material column density and the intensity of the UV field. For a homogeneous, neutral cloud illuminated by a bright OB star, PDR theory predicts that the ultraviolet ( UV) radiation is attenuated exponentially ( e (-1.8Av)). The predicted UV attenuation is confirmed by observations of broad PAH emission features found at 8.6, 11.2, and 12.7 mu m. The PAH emission is found in cool regions having greater optical depths relative to regions where mid-infrared emission from ionized gas is observed. Through modeling we determine a gas density of 9.7 x 10(4) cm(-3). On large and small size scales, the relative strengths of the 8.6, 11.2, and 12.7 mu m PAH features at the bar of the Orion Nebula indicate that there is not a simple transition from ionized to neutral PAHs across the PDR. C1 Keck Observ, Kamuela, HI 96743 USA. Boston Univ, Dept Astron, Boston, MA 02215 USA. Colby Coll, Dept Phys & Astron, Waterville, ME 04901 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Hawaii, NASA, Infrared Telescope Facil, Hilo, HI 96720 USA. EM mkassis@keck.hawaii.edu OI Hora, Joseph/0000-0002-5599-4650 NR 45 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 EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD FEB 1 PY 2006 VL 637 IS 2 BP 823 EP 837 DI 10.1086/498404 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SA UT WOS:000235131600025 ER PT J AU Buffington, A Band, DL Jackson, BV Hick, PP Smith, AC AF Buffington, A Band, DL Jackson, BV Hick, PP Smith, AC TI A search for early optical emission at gamma-ray burst locations by the Solar Mass Ejection Imagger (SMEI) SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; techniques : photometric ID IMAGER SMEI; AFTERGLOW; GRB-021211; MISSION AB The Solar Mass Ejection Imager ( SMEI) views nearly every point on the sky once every 102 minutes and can detect point sources as faint as R similar to 10 mag. Therefore, SMEI can detect or provide upper limits for the optical afterglow from gamma-ray bursts in the tens of minutes after the burst, when different shocked regions may emit optically. Here we provide upper limits for 58 bursts between 2003 February and 2005 April. C1 Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. NASA, Goddard Space Flight Ctr, GLAST SSC, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, Baltimore, MD 21250 USA. RP Buffington, A (reprint author), Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. EM abuffington@ucsd.edu; dband@milkyway.gsfc.nasa.gov; bvjackson@ucsd.edu; pphick@ucsd.edu NR 29 TC 18 Z9 18 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 FEB 1 PY 2006 VL 637 IS 2 BP 880 EP 888 DI 10.1086/498407 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SA UT WOS:000235131600031 ER PT J AU Blustin, AJ Band, D Barthelmy, S Boyd, P Capalbi, M Holland, ST Marshall, FE Mason, KO Perri, M Poole, T Roming, P Rosen, S Schady, P Still, M Zhang, B Angelini, L Barbier, L Beardmore, A Breeveld, A Burrows, DN Cummings, JR Canizzo, J Campana, S Chester, MM Chincarini, G Cominsky, LR Cucchiara, A de Pasquale, M Fenimore, EE Gehrels, N Giommi, P Goad, M Gronwall, C Grupe, D Hill, JE Hinshaw, D Hunsberger, S Hurley, KC Ivanushkina, M Kennea, JA Krimm, HA Kumar, P Landsman, W La Parola, V Markwardt, CB McGowan, K Meszaros, P Mineo, T Moretti, A Morgan, A Nousek, J O'Brien, PT Osborne, JP Page, K Page, MJ Palmer, DM Parsons, AM Rhoads, J Romano, P Sakamoto, T Sato, G Tagliaferri, G Tueller, J Wells, AA White, NE AF Blustin, AJ Band, D Barthelmy, S Boyd, P Capalbi, M Holland, ST Marshall, FE Mason, KO Perri, M Poole, T Roming, P Rosen, S Schady, P Still, M Zhang, B Angelini, L Barbier, L Beardmore, A Breeveld, A Burrows, DN Cummings, JR Canizzo, J Campana, S Chester, MM Chincarini, G Cominsky, LR Cucchiara, A de Pasquale, M Fenimore, EE Gehrels, N Giommi, P Goad, M Gronwall, C Grupe, D Hill, JE Hinshaw, D Hunsberger, S Hurley, KC Ivanushkina, M Kennea, JA Krimm, HA Kumar, P Landsman, W La Parola, V Markwardt, CB McGowan, K Meszaros, P Mineo, T Moretti, A Morgan, A Nousek, J O'Brien, PT Osborne, JP Page, K Page, MJ Palmer, DM Parsons, AM Rhoads, J Romano, P Sakamoto, T Sato, G Tagliaferri, G Tueller, J Wells, AA White, NE TI Swift panchromatic observations of the bright gamma-ray burst GRB 050525a SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; galaxies : distances and redshifts; gamma rays : bursts; shock waves; X-rays : individual (GRB 050525a) ID AFTERGLOW LIGHT CURVES; OPTICAL AFTERGLOWS; PEAK LUMINOSITY; REVERSE-SHOCK; GRB 050525A; ENERGY; GRB-021211; SPECTRA; MODEL; GRB-990123 AB The bright gamma- ray burst GRB 050525a has been detected with the Swift observatory, providing unique multiwavelength coverage from the very earliest phases of the burst. The X- ray and optical / UV afterglow decay light curves both exhibit a steeper slope similar to 0.15 days after the burst, indicative of a jet break. This jet break time combined with the total gamma- ray energy of the burst constrains the opening angle of the jet to be 3 degrees.2. We derive an empirical `` timelag'' redshift from the BAT data of (z) over bar z 0: 69 +/- 0: 02, in good agreement with the spectroscopic redshift of 0.61. Prior to the jet break, the X- ray data can be modeled by a simple power law with index alpha = - 1: 2. However, after 300 s the X- ray flux brightens by about 30% compared to the power- law fit. The optical / UV data have a more complex decay, with evidence of a rapidly falling reverse shock component that dominates in the first minute or so, giving way to a flatter forward shock component at later times. The multiwavelength X- ray/ UV/ optical spectrum of the afterglow shows evidence for migration of the electron cooling frequency through the optical range within 25,000 s. The measured temporal decay and spectral indexes in the X- ray and optical/ UV regimes compare favorably with the standard fireball model for gamma- ray bursts assuming expansion into a constant- density interstellar medium. C1 UCL, Mullard Space Sci Lab, Dept Space & Climate Phys, Dorking RH5 6NT, Surrey, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. ASI Sci Data Ctr, I-00044 Frascati, Rome, Italy. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. INAF Osservatorio Astron Brera, I-23807 Merate, Italy. Sonoma State Univ, Dept Phys & Astron, Rohnert Pk, CA 94928 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. INAF Ist Astrofis Spaziale & Cosm, I-90146 Palermo, Italy. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. RP UCL, Mullard Space Sci Lab, Dept Space & Climate Phys, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. EM ajb@mssl.ucl.ac.uk RI White, Nicholas/B-6428-2012; Barthelmy, Scott/D-2943-2012; Boyd, Patricia/D-3274-2012; Gehrels, Neil/D-2971-2012; Tueller, Jack/D-5334-2012; Lujan Center, LANL/G-4896-2012; Parsons, Ann/I-6604-2012; OI Tagliaferri, Gianpiero/0000-0003-0121-0723; White, Nicholas/0000-0003-3853-3462; Mineo, Teresa/0000-0002-4931-8445; Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; moretti, alberto/0000-0002-9770-0315; Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488 NR 52 TC 95 Z9 95 U1 0 U2 10 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 FEB 1 PY 2006 VL 637 IS 2 BP 901 EP 913 DI 10.1086/498425 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SA UT WOS:000235131600033 ER PT J AU Fullerton, AW Massa, DL Prinja, RK AF Fullerton, AW Massa, DL Prinja, RK TI The discordance of mass-loss estimates for galactic O-type stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : early-type; stars : mass loss; stars : winds, outflows ID ULTRAVIOLET-SPECTROSCOPIC-EXPLORER; COLLIDING STELLAR WINDS; RADIATION-DRIVEN WINDS; SHORT-TERM VARIABILITY; CLOSE BINARY-SYSTEMS; HOT LUMINOUS STARS; FAR-ULTRAVIOLET; ZETA-PUPPIS; LOSS RATES; H-ALPHA AB We have determined accurate values of the product of the mass-loss rate and the ion fraction of P+4, Mq(P+4), for a sample of 40 Galactic O-type stars by fitting stellar wind profiles to observations of the P v resonance doublet obtained with FUSE, ORFEUS BEFS, and Copernicus. When P+4 is the dominant ion in the wind [i.e., 0.5 less than or similar to q(P+4) <= 1],. Mq(P+4) approximates the mass-loss rate to within a factor of less than or similar to 2. Theory predicts that P+4 is the dominant ion in the winds of O7-O9.7 stars, although an empirical estimator suggests that the range O4-O7 may be more appropriate. However, we find that the mass-loss rates obtained from P v wind profiles are systematically smaller than those obtained from fits to H alpha emission profiles or radio free-free emission by median factors of similar to 130 (if P+4 is dominant between O7 and O9.7) or similar to 20 (if P+4 is dominant between O4 and O7). These discordant measurements can be reconciled if the winds of O stars in the relevant temperature range are strongly clumped on small spatial scales. We use a simplified two-component model to investigate the volume filling factors of the denser regions. This clumping implies that mass-loss rates determined from "rho(2)'' diagnostics have been systematically overestimated by factors of 10 or more, at least for a subset of O stars. Reductions in the mass-loss rates of this size have important implications for the evolution of massive stars and quantitative estimates of the feedback that hot-star winds provide to their interstellar environments. C1 Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada. SGT Inc, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. UCL, Dept Phys & Astron, London WC1E 6BT, England. RP Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA. EM awf@pha.jhu.edu; massa@taotaomona.gsfc.nasa.gov; rkp@star.ucl.ac.uk NR 77 TC 185 Z9 185 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 FEB 1 PY 2006 VL 637 IS 2 BP 1025 EP 1039 DI 10.1086/498560 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SA UT WOS:000235131600044 ER PT J AU Colbert, JW Teplitz, H Francis, P Palunas, P Williger, GM Woodgate, B AF Colbert, JW Teplitz, H Francis, P Palunas, P Williger, GM Woodgate, B TI Ultraviolet-bright, high-redshift ultraluminous infrared galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : evolution; galaxies : high-redshift; infrared : galaxies ID LY-ALPHA-NEBULA; IRAS 2-JY SAMPLE; SUBMILLIMETER SURVEY; EMITTING GALAXIES; SPACE-TELESCOPE; PROTOCLUSTER; SPECTROSCOPY; EVOLUTION; LUMINOSITY; REGION AB We present Spitzer Space Telescope observations of the Ly alpha emitter overdensity associated with galaxy cluster J2143-4423, the largest known structure (110 Mpc) above. We imaged 22 of the 37 known Lya emitters within the filament-like structure, using the MIPS 24 mu m band. We detected six of the Lya emitters, including three of the four clouds of extended (150 kpc) Ly alpha emission, also known as Lya blobs. Conversion from a rest wavelength of 7 mm to total far-infrared luminosity using locally derived correlations suggests that all the detected sources are in the class of ultraluminous infrared galaxies (ULIRGs), with some reaching hyper-LIRG energies. Lya blobs frequently show evidence of interaction, either in HST imaging or in the proximity of multiple MIPS sources within the Lya cloud. This connection suggests that interaction or even mergers may be related to the production of Lya blobs. A connection to mergers does not in itself help explain the origin of the Lya blobs, as most of the suggested mechanisms for creating Lya blobs (starbursts, active galactic nuclei, cooling flows) could also be associated with galaxy interactions. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT 0200, Australia. Univ Texas, McDonald Observ, Austin, TX 78712 USA. Univ Louisville, Dept Phys & Astron, Louisville, KY 40292 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Colbert, JW (reprint author), CALTECH, Spitzer Sci Ctr, Mail Code 220-6, Pasadena, CA 91125 USA. NR 37 TC 27 Z9 27 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 FEB 1 PY 2006 VL 637 IS 2 BP L89 EP L92 DI 10.1086/500647 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SD UT WOS:000235131900006 ER PT J AU Watson, D Reeves, JN Hjorth, J Fynbo, JPU Jakobsson, P Pedersen, K Sollerman, J Ceron, JMC McBreen, S Foley, S AF Watson, D Reeves, JN Hjorth, J Fynbo, JPU Jakobsson, P Pedersen, K Sollerman, J Ceron, JMC McBreen, S Foley, S TI Outshining the quasars at reionization: The X-ray spectrum and light curve of the redshift 6.29 gamma-ray burst GRB 050904 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; intergalactic medium; quasars : absorption lines; X-rays : galaxies; X-rays : general ID XMM-NEWTON OBSERVATIONS; INTERGALACTIC MEDIUM; CHANDRA DETECTION; LY-ALPHA; HOST GALAXIES; SUPERNOVA; AFTERGLOW; FOREST; EMISSION; GRB-031203 AB Gamma-ray burst (GRB) 050904 is the most distant X-ray source known, at, comparable to the farthest AGNs and galaxies. Its X- ray flux decays, but not as a power law; it is dominated by large variability from a few minutes to at least half a day. The spectra soften from a power law with photon index G p and are well fit by an absorbed power law with possible evidence of large intrinsic absorption. There is 1.2-1.9 no evidence for discrete features, in spite of the high signal-to-noise ratio. In the days after the burst, GRB 050904 was by far the brightest known X-ray source at. In the first minutes after the burst, the flux was z 1 4 > 10(-9) ergs cm-(2) s(-1) in the 0.2-10 keV band, corresponding to an apparent luminosity > 10(5) times larger than the brightest AGNs at these distances. More photons were acquired in a few minutes with Swift XRT than XMM-Newton and Chandra obtained in similar to 300 ks of pointed observations of AGNs. This observation is a clear z 1 5 demonstration of concept for efficient X-ray studies of the high-z IGM with large-area, high-resolution X-ray detectors and shows that early-phase GRBs are the only backlighting bright enough for X-ray absorption studies of the IGM at high redshift. C1 Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen O, Denmark. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Code 662, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Estec, Res & Sci Support Dept ESA, Astrophys Miss Div, NL-2200 AG Noordwijk, Netherlands. Univ Coll Dublin, Dept Phys, Dublin 2, Ireland. RP Watson, D (reprint author), Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, Juliane Maries Vej 30, DK-2100 Copenhagen O, Denmark. EM darach@astro.ku.dk; jnr@milkyway.gsfc.nasa.gov; jens@astro.ku.dk; jfynbo@astro.ku.dk; pallja@astro.ku.dk; kp@astro.ku.dk; jesper@astro.ku.dk; josemari@alumni.nd.edu; smcbreen@rssd.esa.int; sfoley@bermuda.ucd.ie RI Fynbo, Johan/L-8496-2014; Hjorth, Jens/M-5787-2014; Watson, Darach/E-4521-2015; Jakobsson, Pall/L-9950-2015 OI Fynbo, Johan/0000-0002-8149-8298; Hjorth, Jens/0000-0002-4571-2306; Watson, Darach/0000-0002-4465-8264; Jakobsson, Pall/0000-0002-9404-5650 NR 59 TC 38 Z9 38 U1 0 U2 1 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 FEB 1 PY 2006 VL 637 IS 2 BP L69 EP L72 DI 10.1086/501004 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SD UT WOS:000235131900001 ER PT J AU Watts, AL Strohmayer, TE AF Watts, AL Strohmayer, TE TI Detection with RHESSI of high-frequency X-ray oscillations in the tail of the 2004 hyperflare from SGR 1806-20 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (SGR 1806-20); stars : magnetic fields; stars : neutron; stars : oscillations; stars : rotation; X-rays : stars ID SOFT GAMMA-REPEATERS; GIANT-FLARE; NEUTRON-STARS; RADIATIVE MECHANISM; SGR-1806-20; BURSTS; DISCOVERY; EVOLUTION; EMISSION; PULSAR AB The recent discovery of high-frequency oscillations in giant flares from SGR 1806-20 and SGR 1900+14 may be the first direct detection of vibrations in a neutron star crust. If this interpretation is correct, it offers a novel means of testing the neutron star equation of state, crustal breaking strain, and magnetic field configuration. Using timing data from RHESSI, we have confirmed the detection of a 92.5 Hz quasi-periodic oscillation (QPO) in the tail of the SGR 1806-20 giant flare. We also find another, stronger QPO at higher energies, at 626.5 Hz. Both QPOs are visible only at particular (but different) rotational phases, implying an association with a specific area of the neutron star surface or magnetosphere. At lower frequencies we confirm the detection of an 18 Hz QPO, at the same rotational phase as the 92.5 Hz QPO, and report the additional presence of a broad 26 Hz QPO. We are, however, unable to make a robust confirmation of the presence of a 30 Hz QPO, despite higher count rates. We discuss our results in the light of neutron star vibration models. C1 NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. RP Watts, AL (reprint author), Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85748 Garching, Germany. EM anna@mpa-garching.mpg.de; stroh@milkyway.gsfc.nasa.gov NR 29 TC 123 Z9 124 U1 0 U2 1 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 FEB 1 PY 2006 VL 637 IS 2 BP L117 EP L120 DI 10.1086/500735 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009SD UT WOS:000235131900013 ER PT J AU Buckalew, BA Kobulnicky, HA Darnel, JM Polomski, E Gehrz, RD Humphreys, RM Woodward, CE Hinz, JL Engelbracht, CW Gordon, KD Misselt, K Perez-Gonzalez, PG Rieke, GH Willner, SP Ashby, ML Barmby, P Pahre, MA Roellig, TL Devereux, N Loon, JT Brandl, B AF Buckalew, BA Kobulnicky, HA Darnel, JM Polomski, E Gehrz, RD Humphreys, RM Woodward, CE Hinz, JL Engelbracht, CW Gordon, KD Misselt, K Perez-Gonzalez, PG Rieke, GH Willner, SP Ashby, ML Barmby, P Pahre, MA Roellig, TL Devereux, N Loon, JT Brandl, B TI Understanding radio-selected thermal sources in M33: Ultraviolet, optical, near-infrared, spitzer mid-infrared, and radio observations SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE dust, extinction; galaxies : individual (M33); galaxies : star clusters; infrared : ISM; ISM : structure ID WOLF-RAYET STARS; SUPERNOVA-REMNANTS; GALAXIES; SAMPLE; CLUSTERS; EMISSION; REGIONS; GAS AB We present ultraviolet, optical, near-infrared, Spitzer mid-infrared, and radio images of 14 radio-selected objects in M33. These objects are thought to represent the youngest phase of star cluster formation. We have detected the majority of cluster candidates in M33 at all wavelengths. From the near-IR images, we derived ages 2-10 Myr, K-S-band extinctions (A(Ks)) of 0-1 mag, and stellar masses of 10(3)-10(4) M.. We have generated spectral energy distributions (SEDs) of each cluster from 0.1 to 160 mu m. From these SEDs, we have modeled the dust emission around these star clusters to determine the dust masses (1-10(3) M.) and temperatures (40-90 K) of the clusters' local interstellar medium. Extinctions derived from the JHK(S), H alpha, and UV images are similar to within a factor of 2 or 3. These results suggest that 11 of the 14 radio-selected objects are optically visible young star clusters with a surrounding H II region, that 2 are background objects, possibly active galactic nuclei (AGNs), and that 1 is a Wolf-Rayet star with a surrounding H II region. C1 Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. Univ Minnesota, Dept Astron, Minneapolis, MN 55455 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Embry Riddle Aeronaut Univ, Dept Phys, Prescott, AZ 86301 USA. Univ Keele, Sch Phys & Geog Sci, Astrophys Grp, Keele ST5 5BG, Staffs, England. Leiden Observ, NL-2300 RA Leiden, Netherlands. RP Buckalew, BA (reprint author), CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. EM mrk1236@uwyo.edu; chipk@uwyo.edu; jdarnel@uwyo.edu; gehrz@astro.umn.edu; roberta@astro.umn.edu; chelsea@astro.umn.edu; jhinz@as.arizona.edu; cengelbracht@as.arizona.edu; kgordon@as.arizona.edu; kmisselt@as.arizona.edu; pgperez@as.arizona.edu; grieke@as.arizona.edu; swillner@cfa.harvard.edu; mashby@cfa.harvard.edu; pbarmby@cfa.harvard.edu; mpahre@cfa.harvard.edu; thomas.l.roellig@nasa.gov; devereux@erau.edu; jacco@astro.keele.ac.uk; brandl@isc.astro.cornell.edu RI Barmby, Pauline/I-7194-2016; Perez-Gonzalez, Pablo/J-2871-2016 OI Barmby, Pauline/0000-0003-2767-0090; Perez-Gonzalez, Pablo/0000-0003-4528-5639 NR 21 TC 3 Z9 3 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 FEB PY 2006 VL 162 IS 2 BP 329 EP 345 DI 10.1086/498572 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013QW UT WOS:000235425300003 ER PT J AU Rudolph, AL Fich, M Bell, GR Norsen, T Simpson, JP Haas, MR Erickson, EF AF Rudolph, AL Fich, M Bell, GR Norsen, T Simpson, JP Haas, MR Erickson, EF TI Abundance gradients in the galaxy SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE galaxy : abundances; HII regions; ISM : abundances ID H-II-REGIONS; GALACTIC HII-REGIONS; FINE-STRUCTURE LINES; EFFECTIVE COLLISION STRENGTHS; COMBINED STELLAR STRUCTURE; GUIDE STAR CATALOG; OUTER GALAXY; INTERSTELLAR EXTINCTION; CHEMICAL-COMPOSITION; IRON PROJECT AB Six H II regions at galactocentric distances of R = 10-15 kpc have been observed in the far-IR emission lines of [O III] (52 mu m, 88 mu m), [N III] (57 mu m), and [S III] (19 mu m) using the Kuiper Airborne Observatory. These observations have been combined with Very Large Array radio continuum observations of these sources to determine the abundances of O(++), N(++), and S(++) relative to hydrogen. In addition, eight of the most recent sets of measurements of ionic line strengths in H II regions have been reanalyzed in order to attempt to reconcile differences in optical versus far-IR abundance determinations. We have in total 168 sets of observations of 117 H II regions in our analysis. The new analysis included updating the atomic constants (transition probabilities and collision cross sections), recalculation of some of the physical conditions in the H II regions (n(e) and T(e)), and the use of new photoionization models to determine stellar effective temperatures of the exciting stars. We also use the most recent data available for the distances for these objects, although for most we still rely on kinematic distance determinations. Our analysis finds little indication of differences between optical and infrared observations of the nitrogen abundances, but some differences are seen in the oxygen and sulfur abundances. A very significant offset continues to be seen between optical and infrared measurements of the N/O abundance ratio. C1 Calif State Polytech Univ Pomona, Dept Phys, Pomona, CA 91768 USA. Univ Waterloo, Guelph Waterloo Program Grad Work Phys, Dept Phys, Waterloo, ON N2L 3G1, Canada. Harvey Mudd Coll, Dept Phys, Claremont, CA 91711 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. SETI Inst, Mountain View, CA USA. RP Rudolph, AL (reprint author), Calif State Polytech Univ Pomona, Dept Phys, 3801 W Temple Ave, Pomona, CA 91768 USA. NR 99 TC 100 Z9 103 U1 1 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD FEB PY 2006 VL 162 IS 2 BP 346 EP 374 DI 10.1086/498869 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013QW UT WOS:000235425300004 ER PT J AU Maeda, A De Lucia, FC Herbst, E Pearson, JC Riccobono, J Trosell, E Bohn, RK AF Maeda, A De Lucia, FC Herbst, E Pearson, JC Riccobono, J Trosell, E Bohn, RK TI The millimeter- and submillimeter-wave spectrum of the Gt conformer of n-propanol (n-CH3CH2CH2OH) SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE astrochemistry; methods : laboratory; molecular data ID MICROWAVE ROTATIONAL SPECTRUM; GAUCHE-ETHYL-ALCOHOL; GAS-PHASE; SAGITTARIUS B2; DIETHYL-ETHER; GROUND-STATE; LINE SURVEY; TRANS; GHZ; MOLECULE AB As part of our continuing spectroscopic program of measuring the rotational spectra of large gas-phase molecules that may exist in observable quantities in the interstellar medium, we have studied the millimeter- and submillimeter-wave spectrum of the alcohol n-propanol (n-CH3CH2CH2OH), a straight-chain molecule with one more carbon atom than ethanol, which has already been detected in hot molecular cores. Although the molecule is thought to exist in five different conformers, we have only studied what is most likely to be the Gauche-trans (Gt) conformer, and analyzed over 2800 lines through 375 GHz in frequency. These lines have been added to both previously and newly measured rotational lines at lower frequencies. The global data set has been fitted to experimental accuracy, allowing us to determine accurate spectral parameters so as to predict useful frequencies for many more transitions of the conformer. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Ohio State Univ, Dept Chem, Columbus, OH 43210 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Salisbury Univ, Dept Chem, Salisbury, MD 21801 USA. Univ Connecticut, Dept Chem, Storrs, CT 06269 USA. RP Maeda, A (reprint author), Ohio State Univ, Dept Phys, 174 W 18th Ave, Columbus, OH 43210 USA. NR 48 TC 26 Z9 26 U1 1 U2 3 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 FEB PY 2006 VL 162 IS 2 BP 428 EP 435 DI 10.1086/498870 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 013QW UT WOS:000235425300009 ER PT J AU Clancey, WJ AF Clancey, WJ TI How anchors allow reusing categories in neural composition of sentences SO BEHAVIORAL AND BRAIN SCIENCES LA English DT Editorial Material AB van der Velde's & de Kamps's neural blackboard architecture is similar to "activation trace diagrams" (Clancey 1999), which represent how categories are temporally related as neural activations in parallel-hierarchical compositions. Examination of other comprehension examples suggests that a given syntactic categorization (structure assembly) can be incorporated in different ways within ail open composition by different kinds of anchoring relations (delay assemblies). Anchors are categorizations, too, so they cannot be reused until their containing construction is completed (bindings are resolved). C1 NASA, Ames Res Ctr, Intelligent Syst Div, Moffett Field, CA 94035 USA. RP Clancey, WJ (reprint author), NASA, Ames Res Ctr, Intelligent Syst Div, Moffett Field, CA 94035 USA. EM William.J.Clancey@NASA.gov NR 5 TC 1 Z9 1 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA SN 0140-525X J9 BEHAV BRAIN SCI JI Behav. Brain Sci. PD FEB PY 2006 VL 29 IS 1 BP 73 EP + PG 7 WC Psychology, Biological; Behavioral Sciences; Neurosciences SC Psychology; Behavioral Sciences; Neurosciences & Neurology GA 016PC UT WOS:000235631200020 ER PT J AU Kommu, SS Andrews, RJ Mah, RW AF Kommu, SS Andrews, RJ Mah, RW TI Real-time multiple microsensor tissue recognition and its potential application in the management of prostate cancer SO BJU INTERNATIONAL LA English DT Article DE microsensor; tissue; real-time; prostate; cancer; solid ID RADICAL PROSTATECTOMY; BIOPSY; DIAGNOSIS C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Kommu, SS (reprint author), Royal Marsden Hosp, NHS Fdn Trust, Inst Canc Res, London SW3 6JJ, England. EM sashurol@gmail.com NR 12 TC 5 Z9 5 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1464-4096 J9 BJU INT JI BJU Int. PD FEB PY 2006 VL 97 IS 2 BP 222 EP 223 DI 10.1111/j.1464-410X.2006.05879.x PG 2 WC Urology & Nephrology SC Urology & Nephrology GA 003EM UT WOS:000234664400004 PM 16430616 ER PT J AU Cuxart, J Holtslag, AAM Beare, RJ Bazile, E Beljaars, A Cheng, A Conangla, L Ek, M Freedman, F Hamdi, R Kerstein, A Kitagawa, H Lenderink, G Lewellen, D Mailhot, J Mauritsen, T Perov, V Schayes, G Steeneveld, GJ Svensson, G Taylor, P Weng, W Wunsch, S Xu, KM AF Cuxart, J Holtslag, AAM Beare, RJ Bazile, E Beljaars, A Cheng, A Conangla, L Ek, M Freedman, F Hamdi, R Kerstein, A Kitagawa, H Lenderink, G Lewellen, D Mailhot, J Mauritsen, T Perov, V Schayes, G Steeneveld, GJ Svensson, G Taylor, P Weng, W Wunsch, S Xu, KM TI Single-column model intercomparison for a stably stratified atmospheric boundary layer SO BOUNDARY-LAYER METEOROLOGY LA English DT Article DE GABLS; intercomparison; mixing coefficients; single-column models; stably stratified flows; turbulence parameterizations ID TURBULENCE CLOSURE-MODEL; LARGE-EDDY SIMULATION; PART I; SCHEME; PARAMETERIZATION; FORMULATION; DIFFUSION; DYNAMICS; SURFACES; SYSTEM AB The parameterization of the stably stratified atmospheric boundary layer is a difficult issue, having a significant impact on medium-range weather forecasts and climate integrations. To pursue this further, a moderately stratified Arctic case is simulated by nineteen single-column turbulence schemes. Statistics from a large-eddy simulation intercomparison made for the same case by eleven different models are used as a guiding reference. The single-column parameterizations include research and operational schemes from major forecast and climate research centres. Results from first-order schemes, a large number of turbulence kinetic energy closures, and other models were used. There is a large spread in the results; in general, the operational schemes mix over a deeper layer than the research schemes, and the turbulence kinetic energy and other higher-order closures give results closer to the statistics obtained from the large-eddy simulations. The sensitivities of the schemes to the parameters of their turbulence closures are partially explored. C1 Univ Illes Balears, Dept Fis, E-07071 Palma de Mallorca, Spain. Wageningen Univ, Meteorol & Air Qual Sect, Wageningen, Netherlands. Meteo France, Toulouse, France. European Ctr Medium Range Weather Forecast, Reading, Berks, England. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Univ Politecn Catalunya, Dept Fis Aplicada, Manresa, Spain. NOAA, NCEP, Camp Springs, MD USA. Univ Catholique Louvain, IAG G Lemaitre, B-1348 Louvain, Belgium. Sandia Natl Labs, Livermore, CA 94550 USA. Japan Meteorol Agcy, Tokyo, Japan. Royal Netherlands Meteorol Inst, KNMI, NL-3730 AE De Bilt, Netherlands. W Virginia Univ, Morgantown, WV 26506 USA. Meteorol Serv Canada, Dorval, PQ, Canada. Stockholm Univ, Dept Meteorol, S-10691 Stockholm, Sweden. Swedish Meteorol & Hydrol Inst, Norrkoping, Sweden. York Univ, N York, ON M3J 1P3, Canada. RP Cuxart, J (reprint author), Univ Illes Balears, Dept Fis, E-07071 Palma de Mallorca, Spain. EM joan.cuxart@uib.es RI Lewellen, David/B-1453-2008; Steeneveld, Gert-Jan/B-2816-2010; Xu, Kuan-Man/B-7557-2013; Mauritsen, Thorsten/G-5880-2013; Holtslag, Albert/B-7842-2010 OI lenderink, geert/0000-0002-1572-4867; Steeneveld, Gert-Jan/0000-0002-5922-8179; Xu, Kuan-Man/0000-0001-7851-2629; Mauritsen, Thorsten/0000-0003-1418-4077; Holtslag, Albert/0000-0003-0995-2481 NR 49 TC 145 Z9 147 U1 3 U2 30 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD FEB PY 2006 VL 118 IS 2 BP 273 EP 303 DI 10.1007/s10546-005-3780-1 PG 31 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 057YT UT WOS:000238631800003 ER PT J AU Williams, KD Ringer, MA Senior, CA Webb, MJ McAvaney, BJ Andronova, N Bony, S Dufresne, JL Emori, S Gudgel, R Knutson, T Li, B Lo, K Musat, I Wegner, J Slingo, A Mitchell, JFB AF Williams, KD Ringer, MA Senior, CA Webb, MJ McAvaney, BJ Andronova, N Bony, S Dufresne, JL Emori, S Gudgel, R Knutson, T Li, B Lo, K Musat, I Wegner, J Slingo, A Mitchell, JFB TI Evaluation of a component of the cloud response to climate change in an intercomparison of climate models SO CLIMATE DYNAMICS LA English DT Article ID SEA-SURFACE TEMPERATURE; GENERAL-CIRCULATION MODEL; HADLEY-CENTER; CARBON-DIOXIDE; SIMULATIONS; UNCERTAINTIES; VARIABILITY; ATMOSPHERE; FEEDBACK; IMPACT AB Most of the uncertainty in the climate sensitivity of contemporary general circulation models (GCMs) is believed to be connected with differences in the simulated radiative feedback from clouds. Traditional methods of evaluating clouds in GCMs compare time-mean geographical cloud fields or aspects of present-day cloud variability, with observational data. In both cases a hypothetical assumption is made that the quantity evaluated is relevant for the mean climate change response. Nine GCMs (atmosphere models coupled to mixed-layer ocean models) from the CFMIP and CMIP model comparison projects are used in this study to demonstrate a common relationship between the mean cloud response to climate change and present-day variability. Although atmosphere-mixed-layer ocean models are used here, the results are found to be equally applicable to transient coupled model simulations. When changes in cloud radiative forcing (CRF) are composited by changes in vertical velocity and saturated lower tropospheric stability, a component of the local mean climate change response can be related to present-day variability in all of the GCMs. This suggests that the relationship is not model specific and might be relevant in the real world. In this case, evaluation within the proposed compositing framework is a direct evaluation of a component of the cloud response to climate change. None of the models studied are found to be clearly superior or deficient when evaluated, but a couple appear to perform well on several relevant metrics. Whilst some broad similarities can be identified between the 60 degrees N-60 degrees S mean change in CRF to increased CO2 and that predicted from present-day variability, the two cannot be quantitatively constrained based on changes in vertical velocity and stability alone. Hence other processes also contribute to the global mean cloud response to climate change. C1 Hadley Ctr Climate Predict & Res, Met Off, Exeter EX1 3PB, Devon, England. Univ Reading, Environm Syst Sci Ctr, Reading, Berks, England. Bur Meteorol Res Ctr, Sydney, NSW, Australia. Univ Illinois, Dept Atmospher Sci, Urbana, IL 61801 USA. Inst Pierre Simon Laplace, Paris, France. Natl Inst Environm Studies, Ibaraki, Japan. Geophys Fluid Dynam Lab, Princeton, NJ USA. Goddard Inst Space Studies, New York, NY USA. Max Planck Inst Meteorol, Hamburg, Germany. RP Williams, KD (reprint author), Hadley Ctr Climate Predict & Res, Met Off, FitzRoy Rd, Exeter EX1 3PB, Devon, England. EM keith.williams@metoffice.gov.uk RI Emori, Seita/D-1950-2012; Andronova, Natalia/I-8983-2012; Ringer, Mark/E-7294-2013; Dufresne, Jean-Louis/I-5616-2015; OI Ringer, Mark/0000-0003-4014-2583; Dufresne, Jean-Louis/0000-0003-4764-9600; Bony, Sandrine/0000-0002-4791-4438 NR 47 TC 35 Z9 37 U1 0 U2 10 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0930-7575 EI 1432-0894 J9 CLIM DYNAM JI Clim. Dyn. PD FEB PY 2006 VL 26 IS 2-3 BP 145 EP 165 DI 10.1007/s00382-005-0067-7 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 009RP UT WOS:000235130400003 ER PT J AU Hinchey, MG Sterritt, R AF Hinchey, MG Sterritt, R TI Self-managing software SO COMPUTER LA English DT Editorial Material C1 NASA, Software Engn Lab, Greenbelt, MD USA. Univ Ulster, Sch Comp & Math, Coleraine BT52 1SA, Londonderry, North Ireland. RP Hinchey, MG (reprint author), NASA, Software Engn Lab, Greenbelt, MD USA. EM michael.g.hinchey@nasa.gov; r.sterritt@ulster.ac.uk NR 0 TC 18 Z9 19 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0018-9162 J9 COMPUTER JI Computer PD FEB PY 2006 VL 39 IS 2 BP 107 EP 109 DI 10.1109/MC.2006.69 PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA 010DK UT WOS:000235166900021 ER PT J AU Shirron, P Shirey, K AF Shirron, P Shirey, K TI 2005 Space cryogenics workshop SO CRYOGENICS LA English DT Editorial Material C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Shirron, P (reprint author), NASA, Goddard Space Flight Ctr, Code 552, Greenbelt, MD 20771 USA. EM Peter.Shirron@nasa.gov NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 73 EP 73 DI 10.1016/j.cryogenics.2005.12.007 PG 1 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400001 ER PT J AU Chui, T Zhang, B Barmatz, M Hahn, I Penanen, K Hays, C Strayer, D Liu, YM Zhong, F Young, J Radey, T Jones, J Galitzki, N Li, N Lo, LY Horikoshi, S Hollen, S Paik, HJ AF Chui, T Zhang, B Barmatz, M Hahn, I Penanen, K Hays, C Strayer, D Liu, YM Zhong, F Young, J Radey, T Jones, J Galitzki, N Li, N Lo, LY Horikoshi, S Hollen, S Paik, HJ TI Cryogenics for lunar exploration SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE cryogenics; moon; radiative cooling ID SEISMOGRAPHIC STATION REPORTS; QUARK NUGGET PASSAGE; UNEXPLAINED SETS; CONSISTENT; DYNAMICS AB As part of the refocusing of NASA from Space Station research to exploration research, we are pursuing a number of proposed and funded projects for lunar exploration using cryogenic techniques. This paper gives a summary of these projects which include: (1) Using passive radiative cooling for separation and storage of volatiles from lunar regolith; (2) Studies of boiling and two-phase flow under lunar gravity; (3) SQUID-based MRI for monitoring astronaut health; (4) Studies of volatiles and water ice in permanently shadowed craters at the lunar poles; and (5) Seismic search for strange quark matter using the Moon as a large and seismically quiet detector. (C) 2005 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Low Temp Sci & Quantum Sensor Grp, Pasadena, CA 91109 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. RP Chui, T (reprint author), CALTECH, Jet Prop Lab, Low Temp Sci & Quantum Sensor Grp, 4800 Oak Grove Dr,MS 79-24, Pasadena, CA 91109 USA. EM talso.c.chui@jpl.nasa.gov OI Hollen, Shawna/0000-0002-9158-7876 NR 21 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 74 EP 81 DI 10.1016/j.cryogenics.2005.10.006 PG 8 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400002 ER PT J AU Chato, DJ AF Chato, DJ TI The role of flight experiments in the development of cryogenic fluid management technologies SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE flight experiments; low gravity; fluid management; liquid hydrogen; liquid oxygen; launch vehicles AB This paper reviews the history of cryogenic fluid management technology development and infusion into both the Saturn and Centaur vehicles. Ground testing and analysis proved inadequate to demonstrate full scale performance. As a consequence flight demonstration with full scale vehicle was required by both the Saturn and Centaur programs to build confidence that problems were addressed. However; the flight vehicles were highly limited on flight instrumentation and the flight demonstration "locked-in" the design without challenging the function of design elements. Projects reviewed include: the Aerobee Sounding Rocket Cryogenic Fluid Management (CFM) tests which served as a valuable stepping stone to flight demonstration and built confidence in the ability to handle hydrogen in low gravity; the Saturn IVB Fluid Management Qualification flight test; the Atlas Centaur demonstration flights to develop two burn capability; and finally the Titan Centaur two post mission flight tests. (C) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Chato, DJ (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd,Mail Stop 86-2, Cleveland, OH 44135 USA. EM David.J.Chato@nasa.gov RI Chato, David/B-2698-2013 OI Chato, David/0000-0003-2990-0646 NR 22 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 82 EP 88 DI 10.1016/j.cryogenics.2005.11.010 PG 7 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400003 ER PT J AU Plachta, DW Christie, RJ Jurns, JM Kittel, P AF Plachta, DW Christie, RJ Jurns, JM Kittel, P TI Passive ZBO storage of liquid hydrogen and liquid oxygen applied to space science mission concepts SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE hydrogen; oxygen; space cryogenics; heat transfer AB Liquid hydrogen and oxygen cryogenic propulsion and storage were recently considered for application to Titan Explorer and Comet Nuclear Sample Return space science mission investigations. These missions would require up to 11 years of cryogenic storage. We modeled and designed cryogenic propellant storage concepts for these missions. By isolating the propellant tank's view to deep space, we were able to achieve zero boil-off for both liquid hydrogen and oxygen propellant storage without cryocoolers. Several shades were incorporated to protect the tanks from the sun and spacecraft bus, and to protect the hydrogen tank from the warmer oxygen tank. This had a dramatic effect on the surface temperatures of the propellant tank insulation. These passive storage concepts for deep space missions substantially improved this application of cryogenic propulsion. It is projected that for missions requiring larger propellant tank sizes, the results would be even more dramatic. Published by Elsevier Ltd. C1 NASA, Glenn Res Ctr, Propellant Syst Branch, Cleveland, OH 44135 USA. Zin Technol, Cleveland, OH USA. QSS, Cleveland, OH USA. RP Plachta, DW (reprint author), NASA, Glenn Res Ctr, Propellant Syst Branch, 21000 Brookpk Rd,Mail Stop 86-2, Cleveland, OH 44135 USA. EM david.w.plachta@nasa.gov NR 11 TC 6 Z9 13 U1 0 U2 10 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 89 EP 97 DI 10.1016/j.cryogenics.2005.11.012 PG 9 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400004 ER PT J AU Jurns, JM Kudlac, MT AF Jurns, JM Kudlac, MT TI NASA Glenn Research Center Creek Road Complex - Cryogenic testing facilities SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE space cryogenics; cryostats; hydrogen; oxygen; nitrogen AB Due to expansion at neighboring Cleveland Hopkins Airport, several NASA Glenn Research Center (GRC) facilities have been relocated to the Creek Road Complex. The complex consists of the Small Scale Multi-purpose Research Facility (SMiRF), Cryogenic Components Lab Cell 7 (CCL-7), and a shop building. The facilities have been updated and include state-of-the art technology. SMiRF is a liquid hydrogen/liquid nitrogen (LH2/LN2) test facility used to conduct research in a 7400 L vacuum chamber. The chamber simulates space environment and launch vehicle ascent profile. SMiRF handles 5680 L of LH2. CCL is a LH2/LN2 facility to perform small scale proof of concept tests for components and processes. It handles 1130 L of liquid hydrogen. Both facilities handle cryogens at sub-atmospheric pressures. (C) 2005 Elsevier Ltd. All rights reserved. C1 QSS Grp Inc, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Jurns, JM (reprint author), QSS Grp Inc, 21000 Brookpk Rd, Cleveland, OH 44135 USA. EM John.M.Jurns@nasa.gov NR 7 TC 10 Z9 10 U1 1 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 98 EP 104 DI 10.1016/j.cryogenics.2005.11.014 PG 7 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400005 ER PT J AU Shu, QS Cheng, GF Susta, JT Hull, JR Fesmire, JE Augustanowicz, SD Demko, JA Werfel, FN AF Shu, QS Cheng, GF Susta, JT Hull, JR Fesmire, JE Augustanowicz, SD Demko, JA Werfel, FN TI Magnetic levitation technology and its applications in exploration projects SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE magnetic levitation; high T-c superconductors; cryostats; space cryogenics; superconducting bearings ID TRANSFER LINE AB An energy efficient cryogenic transfer line with magnetic suspension has been prototyped and cryogenically tested. The prototype transfer line exhibits cryogen saving potential of 30-35% in its suspension state as compared to its solid support state. Key technologies developed include novel magnetic levitation using multiple-pole high temperature superconductor (HTS) and rare earth permanent-magnet (PM) elements and a smart cryogenic actuator as the warm support structure. These technologies have vast applications in extremely low thermal leak cryogenic storage/delivery containers, superconducting magnetic bearings, smart thermal switches, etc. This paper reviews the development work and discusses future applications of established technologies. (C) 2005 Elsevier Ltd. All rights reserved. C1 AMAC Int Inc, Newport News, VA 23606 USA. NASA, Sierra Lobo Inc, KSC, Kennedy Space Ctr, FL 32899 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Adelwitz Technol Zentrum GmbH, D-04886 Arzberg, Germany. RP Shu, QS (reprint author), AMAC Int Inc, Newport News, VA 23606 USA. EM qsshu@amacintl.com NR 11 TC 8 Z9 10 U1 0 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 105 EP 110 DI 10.1016/j.cryogenics.2005.10.009 PG 6 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400006 ER PT J AU Fesmire, JE AF Fesmire, JE TI Aerogel insulation systems for space launch applications SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE polymers; thermal conductivity; transport properties; cryostats; space cryogenics AB New developments in materials science in the areas of solution gelation processes and nanotechnology have led to the recent commercial production of aerogels. Concurrent with these advancements has been the development of new approaches to cryogenic thermal insulation systems. For example, thermal and physical characterizations of aerogel beads under cryogenic-vacuum conditions have been performed at the Cryogenics Test Laboratory of the NASA Kennedy Space Center. Aerogel-based insulation system demonstrations have also been conducted to improve performance for space launch applications. Subscale cryopumping experiments show the thermal insulating ability of these fully breathable nanoporous materials. For a properly executed thermal insulation system, these breathable aerogel systems are shown to not cryopump beyond the initial cooldown and thermal stabilization phase. New applications are being developed to augment the thermal protection systems of space launch vehicles, including the Space Shuttle External Tank. These applications include a cold-boundary temperature of 90 K with an ambient air environment in which both weather and flight aerodynamics are important considerations. Another application is a nitrogen-purged environment with a cold-boundary temperature of 20 K where both initial cooldown and launch ascent profiles must be considered. Experimental results and considerations for these flight system applications are discussed. Published by Elsevier Ltd. C1 NASA, Kennedy Space Ctr, Cryogenics Test Lab, Kennedy Space Ctr, FL 32899 USA. RP Fesmire, JE (reprint author), NASA, Kennedy Space Ctr, Cryogenics Test Lab, Mail Code YA-C2-T, Kennedy Space Ctr, FL 32899 USA. EM James.E.Fesmire@nasa.gov NR 12 TC 76 Z9 90 U1 2 U2 43 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 111 EP 117 DI 10.1016/j.cryogenics.2005.11.007 PG 7 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400007 ER PT J AU Van Dresar, NT AF Van Dresar, NT TI PVT gauging with liquid nitrogen SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE nitrogen; instrumentation; level detection; space cryogenics ID HELIUM; SYSTEM; PHASE AB Experimental results are presented for pressure-volume-temperature (PVT) liquid quantity gauging of a 0.17 m(3) liquid nitrogen tank pressured with ambient temperature helium in the normal gravity environment. A previously reported PVT measurement procedure has been improved to include helium solubility in liquid nitrogen. Gauging data was collected at nominal tank fill levels of 80%, 50% and 20% and at nominal tank pressures of 0.3, 1.0, and 1.7 MPa. The test tank was equipped with a liquid pump and spray manifold to circulate and mix the fluid contents and therefore create near-isothermal conditions throughout the tank. Silicon diode sensors were distributed throughout the tank to monitor temperatures. Close-spaced arrays of silicon diode point sensors were utilized to precisely detect the liquid level at the nominal 80%, 50%, and 20% fill levels. The tests simulated the cryogenic tank-side conditions only; helium mass added to the tank was measured by gas flowmeters rather than using pressure and temperature measurements from a dedicated helium supply bottle. Equilibrium data for cryogenic nitrogen and helium mixtures from numerous sources was correlated to predict soluble helium mole fractions. Results show that solubility should be accounted for in the PVT gauging calculations. Mole fractions predicted by Dalton's Law were found to be in good agreement with the compiled equilibrium data within the temperature pressure range of interest. Therefore, Dalton's Law was deemed suitable for calculating ullage composition. Gauging results from the PVT method agreed with the reference liquid level measurements to within 3%. Published by Elsevier Ltd. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Van Dresar, NT (reprint author), NASA, Glenn Res Ctr, MS 86-2,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM neil.t.vandresar@nasa.gov NR 16 TC 2 Z9 2 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 118 EP 125 DI 10.1016/j.cryogenics.2005.10.001 PG 8 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400008 ER PT J AU Shirey, K Banks, S Boyle, R Unger, R AF Shirey, K Banks, S Boyle, R Unger, R TI Design and qualification of the AMS-02 flight cryocoolers SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE Stirling; space cryogenics AB Four commercial Sunpower M87N Stirling-cycle cryocoolers will be used to extend the lifetime of the Alpha Magnetic Spectrometer-02 (AMS-02) experiment. The cryocoolers will be mounted to the AMS-02 vacuum case using a structure that will thermally and mechanically decouple the cryocooler from the vacuum case. This paper discusses modifications of the Sunpower M87N cryocooler to make it acceptable for space flight applications and suitable for use on AMS-02. Details of the flight model qualification test program are presented. AMS-02 is a state-of-the-art particle physics detector containing a large superfluid helium-cooled superconducting magnet. Highly sensitive detector plates inside the magnet measure a particle's speed, mass, charge, and direction. The AMS-02 experiment, which will be flown as an attached payload on the International Space Station, will study the properties and origin of cosmic particles and nuclei including antimatter and dark matter. Two engineering model cryocoolers have been under test at NASA Goddard since November 2001. Qualification testing of the engineering model cryocooler bracket assembly including random vibration and thermal vacuum testing was completed at the end of April 2005. The flight cryocoolers were received in December 2003. Acceptance testing of the flight cryocooler bracket assemblies began in May 2005. Published by Elsevier Ltd. C1 NASA, Goddard Space Flight Ctr, Cryogenics & Fluids Branch, Greenbelt, MD 20771 USA. Sunpower Inc, Athens, OH 45701 USA. RP Shirey, K (reprint author), NASA, Goddard Space Flight Ctr, Cryogenics & Fluids Branch, Code 552, Greenbelt, MD 20771 USA. EM Kimberly.Shirey@nasa.gov NR 10 TC 1 Z9 1 U1 1 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 143 EP 148 DI 10.1016/j.cryogenics.2005.11.016 PG 6 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400011 ER PT J AU Pourrahimi, S Tuttle, J Williams, J Pourrahimi, N Shirron, P AF Pourrahimi, S Tuttle, J Williams, J Pourrahimi, N Shirron, P TI Manufacturing of lightweight low-current Nb3Sn ADR magnets operating at 10 K SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE superconducting magnets; Nb3Sn; low-current; 10 K AB Adiabatic demagnetization refrigerators (ADRs) using superconducting magnets are under development for cooling many NASA instruments. Due to higher efficiency of cryocoolers at 10 K, Nb3Sn magnets operating at 10 K are favored for space ADRs. Further, magnets need to be as light as possible and have low operating currents. This paper discusses technologies for the manufacture of lightweight. low-current Nb3Sn magnets and reports on testing of a 35 mm bore by 60 mm long magnet. This magnet weighed less than I kg and successfully produced 3 T at 11.5 K with an operating current of 8 A. (C) 2005 Elsevier Ltd. All rights reserved. C1 Superconducting Syst Inc, Waltham, MA 02453 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Pourrahimi, S (reprint author), Superconducting Syst Inc, 90 Rumford Ave, Waltham, MA 02453 USA. EM pourrahimi@superconductingsystems.com NR 6 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 191 EP 195 DI 10.1016/j.cryogenics.2005.10.008 PG 5 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400018 ER PT J AU Tuttle, J Pourrahimi, S Canavan, E DiPirro, M Shirron, P AF Tuttle, J Pourrahimi, S Canavan, E DiPirro, M Shirron, P TI A lightweight low-current 10 K magnet for space-flight ADRs SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Gooddard Space Flight Ctr DE adiabatic demagnetization; superconducting magnets AB Future space missions will include detectors and other components cooled to cryogenic temperatures by adiabatic demagnetization refrigerators (ADRs) coupled with mechanical cryocoolers. In such systems the ADRs require lightweight, low-current superconducting magnets. At least one of an ADR's magnets must operate at the cryocooler's coldest stage temperature. This temperature should be as high as possible in order to improve operating efficiency and design flexibility. Until now all space-flight compatible magnets have been made with NbTi wire, which has limited their operating temperatures to below about 5 K. We have developed a lightweight (1 Kg) low-current (8 A) Nb3Sn magnet which produces a 3 T central field at 10 K. We explain the choice of this magnet's specifications and describe its performance testing. Published by Elsevier Ltd. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Superconducting Syst Inc, Waltham, MA 02453 USA. RP Tuttle, J (reprint author), NASA, Goddard Space Flight Ctr, Code 552, Greenbelt, MD 20771 USA. EM jim.tuttle@nasa.gov NR 2 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 196 EP 200 DI 10.1016/j.cryogenics.2005.10.005 PG 5 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400019 ER PT J AU Patterson, RL Hammoud, A Elbuluk, M AF Patterson, RL Hammoud, A Elbuluk, M TI Assessment of electronics for cryogenic space exploration missions SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop (SCW) CY AUG 25-26, 2005 CL Colorado Springs, CO SP Goddard Space Flight Ctr DE cryoelectronics; space electronics; semiconductors; power applications ID DC-DC CONVERTER; TEMPERATURE OPERATION AB Space exploration missions require electronics capable of efficient and reliable operation at low temperatures. Presently, spacecraft on-board electronics are maintained at approximately 20 degrees C through the use of radioisotopes. Cryogenic electronics would enhance efficiency of space systems, improve reliability, and simplify their design. A Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electronics suitable for space exploration missions. The effects of cryogenic temperature and thermal cycling are being investigated for commercial-off-the-shelf components as well as for components specially developed for low temperature operation. An overview of this program along with selected experimental data is presented in this paper. (C) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Glenn Res Ctr, Electrophys Branch, Cleveland, OH 44135 USA. NASA, QSS Grp Inc, Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Akron, Dept Elect Engn, Akron, OH 44325 USA. RP Patterson, RL (reprint author), NASA, Glenn Res Ctr, Electrophys Branch, 21000 Brookpk Rd,MS 301-5, Cleveland, OH 44135 USA. EM Richard.L.Patterson@grc.nasa.gov NR 12 TC 6 Z9 7 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB-MAR PY 2006 VL 46 IS 2-3 BP 231 EP 236 DI 10.1016/j.cryogenics.2005.12.002 PG 6 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 022YP UT WOS:000236092400024 ER PT J AU Durgun, E Senger, RT Mehrez, H Dag, S Ciraci, S AF Durgun, E Senger, RT Mehrez, H Dag, S Ciraci, S TI Nanospintronic properties of carbon-cobalt atomic chains SO EUROPHYSICS LETTERS LA English DT Article AB Periodic atom chains of carbon-cobalt compounds, (CnCo)(infinity), comprise both conducting and insulating electronic properties simultaneously depending on the spin type of electrons, and hence are half-metals. Their band gap and the net magnetic moment oscillate with the number of carbon atoms in a unit cell. Finite segments of these chains also show interesting magnetic and transport properties. When connected to appropriate metallic electrodes the antiferromagnetic CoCnCo segments behave like molecular spin-valves, which can be conveniently manipulated. C1 Bilkent Univ, Dept Phys, TR-06800 Ankara, Turkey. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Bilkent Univ, Dept Phys, TR-06800 Ankara, Turkey. RI Senger, Tugrul/B-8207-2009 OI Senger, Tugrul/0000-0003-0800-1924 NR 21 TC 16 Z9 17 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 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD FEB PY 2006 VL 73 IS 4 BP 642 EP 648 DI 10.1209/epl/i2005-10432-4 PG 7 WC Physics, Multidisciplinary SC Physics GA 018PS UT WOS:000235777900024 ER PT J AU McGraw, CM Bell, JH Khalil, G Callis, JB AF McGraw, CM Bell, JH Khalil, G Callis, JB TI Dynamic surface pressure measurements on a square cylinder with pressure sensitive paint SO EXPERIMENTS IN FLUIDS LA English DT Article ID LUMINESCENT COATINGS; CROSS-SECTION; STREAM; TURBULENCE; POLYMER; FILMS AB The dynamic and static surface pressure on a square cylinder during vortex shedding was measured with pressure sensitive paints (PSPs) at three angles of incidence and a Reynolds number of 8.9 x 10(4). Oscillations in the phosphorescence intensity of the PSP that occurred at the vortex shedding frequency were observed. From these phosphorescent oscillations, the time-dependent changes in pressure distribution were calculated. This work extends PSP's useful range to dynamic systems where oscillating pressure changes are on the order of 230 Pa and occur at frequencies in the range of 95-125 Hz. C1 Univ Washington, Dept Chem, Seattle, WA 98195 USA. NASA, Ames Res Ctr, Expt Phys Branch, Moffett Field, CA 94035 USA. RP McGraw, CM (reprint author), Univ Washington, Dept Chem, Seattle, WA 98195 USA. EM callis@u.washington.edu NR 17 TC 13 Z9 13 U1 0 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD FEB PY 2006 VL 40 IS 2 BP 203 EP 211 DI 10.1007/s00348-005-0059-8 PG 9 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 004LX UT WOS:000234755400006 ER PT J AU Morisette, JT Jarnevich, CS Ullah, A Cai, WJ Pedelty, JA Gentle, JE Stohlgren, TJ Schnase, JL AF Morisette, JT Jarnevich, CS Ullah, A Cai, WJ Pedelty, JA Gentle, JE Stohlgren, TJ Schnase, JL TI A tamarisk habitat suitability map for the continental United States SO FRONTIERS IN ECOLOGY AND THE ENVIRONMENT LA English DT Article ID MODIS; REGRESSION; VEGETATION; CHINENSIS; COVER AB This paper presents a national-scale map of habitat suitability for tamarisk (Tamarix spp, salt cedar), a high-priority invasive species. We successfully integrate satellite data and tens of thousands of field sampling points through logistic regression modeling to create a habitat suitability map that is 90% accurate. This interagency effort uses field data collected and coordinated through the US Geological Survey and nationwide environmental data layers derived from NASA's MODerate Resolution Imaging Spectroradiometer (MODIS). We demonstrate the use of the map by ranking the 48 continental US states (and the District of Columbia) based on their absolute, as well as proportional, areas of "highly likely" and "moderately likely" habitat for Tamarix. The interagency effort and modeling approach presented here could be used to map other harmful species, in the US and globally. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. US Geol Survey, Ft Collins Sci Ctr, Ft Collins, CO USA. Sci Syst Applicat Inc, Greenbelt, MD USA. George Mason Univ, Fairfax, VA 22030 USA. RP Morisette, JT (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 614-5, Greenbelt, MD 20771 USA. EM jeff.morisette@nasa.gov RI Evangelista, Paul/F-4801-2011 NR 16 TC 77 Z9 79 U1 1 U2 25 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 1540-9295 J9 FRONT ECOL ENVIRON JI Front. Ecol. Environ. PD FEB PY 2006 VL 4 IS 1 BP 11 EP 17 DI 10.1890/1540-9295(2006)004[0012:ATHSMF]2.0.CO;2 PG 7 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 009WF UT WOS:000235143400015 ER PT J AU Campbell, S Liang, MI AF Campbell, S Liang, MI TI High-temperature thermosetting polyimide nanocomposites prepared with reduced charge organoclay SO HIGH PERFORMANCE POLYMERS LA English DT Article DE nanocomposite; thermal oxidative stability; wide angle X-ray diffraction ID SILICATE NANOCOMPOSITES; MONTMORILLONITE; DIAMINES AB The naturally occurring sodium and calcium cations found in bentonite clay galleries were exchanged with lithium cations. Following the cation exchange, a series of reduced charge clays were prepared by heat treatment of the lithium bentonite at 130, 150, or 170 degrees C. Inductively coupled plasma analysis showed that heating the lithium clay at elevated temperatures reduced its cation exchange capacity. Ion exchange of heat-treated clays with either a protonated alkyl amine or a protonated aromatic diamine resulted in decreasing amounts of the organic modifier incorporated into the lithium clay. The level of silicate dispersion in a thermosetting polyimide matrix was dependent upon the temperature of Li-clay heat treatment as well as the organic modification. In general, clays treated at 150 or 170 degrees C, and exchanged with protonated octadecylamine or protonated 2,2'-dimethylbenzidine showed a higher degree of dispersion than clays treated at 130 degrees C, or exchanged with protonated dodecylamine. Dynamic mechanical analysis showed little change in the storage modulus or T-g of the nanocomposites compared to the base resin. However, long-term isothermal aging of the samples showed a significant decrease in the resin oxidative weight loss. Nanocomposite samples aged in air for 1000 h at 288 degrees C showed up to a 20% decrease in weight loss in comparison with that of the base resin. This again was dependent on the temperature at which the Li-clay was heated and the choice of organic modification. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Ohio State Univ, Columbus, OH 43210 USA. RP Campbell, S (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM Sandi.G.Campbell@nasa.gov NR 22 TC 5 Z9 5 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 FEB PY 2006 VL 18 IS 1 BP 71 EP 82 DI 10.1177/0954008306055186 PG 12 WC Polymer Science SC Polymer Science GA 012ZB UT WOS:000235378300006 ER PT J AU Warell, J Sprague, AL Emery, JP Kozlowski, RWH Long, A AF Warell, J Sprague, AL Emery, JP Kozlowski, RWH Long, A TI The 0.7-5.3 mu m IR spectra of Mercury and the Moon: Evidence for high-Ca clinopyroxene on Mercury SO ICARUS LA English DT Article DE mercury; mineralogy; regoliths; surfaces, planets; spectroscopy ID SURFACE THERMAL-GRADIENTS; HERMEAN REGOLITH; REFLECTANCE SPECTRA; EMISSION-SPECTRA; IRRADIANCE CALIBRATION; PLANETARY SURFACES; LUNAR; SPECTROSCOPY; COPERNICUS; SPECTROGRAPH AB We present infrared spectra of Mercury and the Moon in the wavelength range 0.7-5.3 mu m obtained with the SpeX spectrograph at the NASA Infrared Telescope Facility. The spectra were acquired from pole and terminator locations of Mercury's Surface and of Mersenius C and the Copernicus central peak on the Moon. Spectra of both bodies were measured in close temporal succession and were reduced in the same manner with identical calibration stars to minimize differences in the reduction process. The Copernicus spectra display the expected absorption features due to mafic minerals in the near infrared and show spectral features in the SiO combination/overtone vibrational band region above 4 mu m. The spectra of Mercury from longitude 170 degrees and north and south mid-latitudes display a 1-mu m absorption band indicative of high-Ca clinopyroxene, while a spectrum from longitude 260 degrees and northern mid-latitudes does not. The Mercury spectra show a broad feature of low emittance over the full 3-5 mu m thermal infrared region, but no narrow features in this spectral range. The longitude 260 degrees spectrum shows excess thermal emission around 5 mu m attributable to the existence of a thermal gradient in the insolated dayside regolith. The thermal-IR spectra suggest a significant difference in the compositional and/or structural properties of Mercury and the Moon that may be due to grain size, absorption coefficient, or the magnitude of near-surface thermal gradients. The results indicate that the composition of Mercury's surface is heterogeneous on regional scales, and that the near infrared wavelength range provides more discriminative information on the surface composition than the 2-4 mu m region, where the solar reflected and thermally emitted radiation contribute approximately equally to the observed flux of these bodies. (c) 2005 Elsevier Inc. All rights reserved. C1 Uppsala Univ, Inst Astron Rymdfysik, SE-75120 Uppsala, Sweden. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. NASA Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. Susquehanna Univ, Phys Dept, Selinsgrove, PA 17870 USA. RP Warell, J (reprint author), Uppsala Univ, Inst Astron Rymdfysik, Box 515, SE-75120 Uppsala, Sweden. EM johan.warell@astro.uu.se RI peut.etre, peut.etre/G-7835-2015 NR 61 TC 48 Z9 48 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 FEB PY 2006 VL 180 IS 2 BP 281 EP 291 DI 10.1016/j.icarus.2005.09.007 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200001 ER PT J AU Hoogenboom, T Houseman, GA AF Hoogenboom, T Houseman, GA TI Rayleigh-Taylor instability as a mechanism for corona formation on Venus SO ICARUS LA English DT Article DE Venus ID NONLINEAR VISCOSITY; MANTLE LITHOSPHERE; CONVECTION; TECTONICS; DEFORMATION; EVOLUTION; MODELS; MAGELLAN; GRAVITY; DIAPIRS AB In this study we explore the idea that coronae have formed on Venus as a result of gravitational (Rayleigh-Taylor) instability of the lithosphere. The lithosphere is represented by a system of stratified homogeneous viscous layers (low-density crust over high density mantle, over lower density layer beneath the lithosphere). A small harmonic perturbation imposed on the base of the lithosphere is observed to result in gravitational instability under the constraint of assumed axisymmetry. Topography develops with time under the influence of dynamic stress associated with downwelling or upwelling, and spatially variable crustal thickening or thinning. Topography may therefore be elevated or depressed above a mantle downwelling, but the computed gravity anomaly is always negative above a mantle downwelling in a homogeneous asthenosphere. The ratio of peak gravity to topography anomaly depends primarily on the ratio of crust to lithospheric viscosity. Average observed ratios are well resolved for two groups of coronae ( similar to 40 mgal km(-1)), consistent with models in which the crust is perhaps 5 times stronger than the lithosphere. Group 3a (rim surrounding elevated central region) coronae are inferred to arise from a central upwelling model, whereas Group 8 (depression) coronae are inferred to arise from central downwelling. Observed average coronae radii are consistent with a lithospheric thickness of only 50 km. An upper low-density crustal layer is 10-20 km thick, as inferred from the amplitude of gravity and topography anomalies. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Leeds, Sch Earth Sci, Leeds LS2 9JT, W Yorkshire, England. RP Hoogenboom, T (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 183-501, Pasadena, CA 91109 USA. EM trudi@jpl.nasa.gov; greg@earth.leeds.ac.uk NR 46 TC 31 Z9 31 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 FEB PY 2006 VL 180 IS 2 BP 292 EP 307 DI 10.1016/j.icarus.2005.11.001 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200002 ER PT J AU Spanovich, N Smith, MD Smith, PH Wolff, MJ Christensen, PR Squyres, SW AF Spanovich, N Smith, MD Smith, PH Wolff, MJ Christensen, PR Squyres, SW TI Surface and near-surface atmospheric temperatures for the Mars Exploration Rover landing sites SO ICARUS LA English DT Article DE Mars, atmosphere; Mars, climate; Mars, surface ID TES AB Downward-looking spectra of the martian surface from the Miniature Thermal Emission spectrometer (Mini-TES), onboard each of the two Mars Exploration Rovers, are modeled in order to retrieve surface and near-surface atmospheric temperatures. By fitting the observed radiance in the vicinity of the 15-mu m CO2 absorption feature, the surface temperature and the near-surface atmospheric temperature, approximately 1.1 m above the surface, are determined. The temperatures from the first 180 sols (martian days) of each surface mission are used to characterize the diurnal dependence of temperatures. The near-surface atmospheric temperatures are consistently 20 K cooler than the surface temperatures in the warmest part of each sol, which is 1300-1400 LTST (local true solar time) depending on the location. Seasonal cooling trends are seen in the data by displaying the temperatures as a function of sol. Long ground stares, 8.5 min in duration, show as much as 8 K fluctuation in the near-surface atmospheric temperatures during the early afternoon hours when the near-surface atmosphere is unstable. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Space Sci Inst, Brookfield, WI 53045 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Spanovich, N (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 264-422, Pasadena, CA 91109 USA. EM nicole.spanovich@jpl.nasa.gov RI Smith, Michael/C-8875-2012 NR 9 TC 27 Z9 28 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 FEB PY 2006 VL 180 IS 2 BP 314 EP 320 DI 10.1016/j.icarus.2005.09.014 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200004 ER PT J AU Prange, R Fouchet, T Courtin, R Connerney, JEP McConnell, JC AF Prange, R Fouchet, T Courtin, R Connerney, JEP McConnell, JC TI Latitudinal variation of Saturn photochemistry deduced from spatially-resolved ultraviolet spectra SO ICARUS LA English DT Article DE atmospheres, composition; photochemistry; Saturn, atmosphere; ultraviolet observations ID ABSORPTION CROSS-SECTIONS; HUBBLE-SPACE-TELESCOPE; JOVIAN STRATOSPHERE; JUPITERS STRATOSPHERE; WATER-VAPOR; ATMOSPHERE; RINGS; IONOSPHERE; MODEL; C2H2 AB We obtained spatially-resolved ultraviolet spectra of Saturn in 1994 with the Faint Object Spectrometer and Goddard High Resolution Spectrograph of the Hubble Space Telescope. We observed four areas on the planet at 15 degrees N. 33 degrees S. 41 degrees S, and 52 degrees S, with a field-of-view of less than 2 x 2 arcsec(2), compared to the 16-arcsec planet diameter. The wavelength range, 1550-2300 angstrom, encompasses absorption from major hydro-carbons (C2H6, C2H4, C2H2, CH3C2H, C4H2) and water. We find global hydrocarbon abundances and a C2H2 vertical distribution compatible with infrared observations, in contrast with previous analyses of ultraviolet spectra. The stratospheric haze opacity decreases from polar region to the equator. Saturn mid-latitudes are photochemically distinct from the rest of the planet. At 33 degrees S. the spectrum requires either (1) a distinctly different C2H2 vertical distribution or (2) a locally enhanced water abundance. At 41 degrees S, the hydrocarbon abundance exhibits a local minimum, within a global trend of increasing abundance from equator to pole. This global trend may result from an increased abundance of short-lived hydrocarbons such as C4H2. Photochemical models predict a depletion of hydrocarbon molecules in the presence of stratospheric water [Moses et al., 2000. Icarus 143, 166-202]. These results are consistent with a localized influx of water. in the form of high charge to mass ratio particles, flowing into Saturn's atmosphere at latitudes magnetically linked to the rings. (c) 2005 Elsevier Inc. All rights reserved. C1 LESIA, Observ Paris, F-92195 Meudon, France. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. CNRS, UMR 8617, F-91405 Orsay, France. Univ Oxford, Clarendon Lab, AOPP, Oxford OX1 3PU, England. Goddard Space Flight Ctr, Lab Extraterr Phys, Greenbelt, MD 20771 USA. Univ York, Dept Earth & Atmospher Sci, Toronto, ON M3J 1P3, Canada. RP Fouchet, T (reprint author), LESIA, Observ Paris, 5 Pl Jules Janssen, F-92195 Meudon, France. EM thierry.fouchet@obspm.fr RI connerney, john/I-5127-2013; Fouchet, Thierry/C-6374-2017; OI Fouchet, Thierry/0000-0001-9040-8285; connerney, jack/0000-0001-7478-6462 NR 74 TC 22 Z9 22 U1 2 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 EI 1090-2643 J9 ICARUS JI Icarus PD FEB PY 2006 VL 180 IS 2 BP 379 EP 392 DI 10.1016/j.icarus.2005.11.005 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200011 ER PT J AU Johnson, RE Luhmann, JG Tokar, RL Bouhram, M Berthelier, JJ Sittler, EC Cooper, JF Hill, TW Smith, HT Michael, M Liu, M Crary, FJ Young, DT AF Johnson, RE Luhmann, JG Tokar, RL Bouhram, M Berthelier, JJ Sittler, EC Cooper, JF Hill, TW Smith, HT Michael, M Liu, M Crary, FJ Young, DT TI Production, ionization and redistribution of O-2 in Saturn's ring atmosphere SO ICARUS LA English DT Article DE Saturn; magnetosphere; atmosphere; rings ID WATER ICE; INNER MAGNETOSPHERE; GALILEAN SATELLITES; OXYGEN ATMOSPHERE; HEAVY-IONS; PLASMA; RADIATION; EROSION; SURFACE; SYSTEM AB Molecular oxygen produced by the decomposition of icy surfaces is ubiquitous in Saturn's magnetosphere. A model is described for the toroidal O-2 atmosphere indicated by the detection of O-2(+) and O+ over the main rings. The O-2 ring atmosphere is produced primarily by UV photon-induced decomposition of ice oil the sunlit side of the ring. Because O-2 has a long lifetime and interacts frequently with the ring particles, equivalent columns of O-2 exist above and below the ring plane with the scale height determined by the local ring temperature. Energetic particles also decompose ice, but estimates of their contribution over the main rings appear to be very low. In steady state the O-2 column density over the rings also depends on the relative efficiency of hydrogen to oxygen loss from the ring/atmosphere system with oxygen being recycled oil the grain surfaces. Unlike the neutral density, the ion densities call differ oil the Sunlit and shaded sides due to differences in the ionization rate, the quenching of ions by the interaction with the ring particles, and the northward shift of the magnetic equator relative to the ring plane. Although O+ is produced with a significant excess energy O-2(+) is not. Therefore. O-2(+) should mirror well below those altitudes at which ions were detected. However, scattering by ion-molecule collisions results in much larger mirror altitudes, in ion temperatures that go through a minimum over the B-ring, and in the redistribution of both molecular hydrogen and oxygen throughout the magnetosphere. The proposed model is used to describe the measured oxygen ion densities in Saturn's toroidal ring atmosphere and its hydrogen content. The oxygen ion densities over the B-ring appear to require either significant levels of UV light scattering or ion transmission through the ring plane. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Virginia, Charlottesville, VA 22904 USA. NYU, Dept Phys, New York, NY 10003 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. Observ St Maur, Ctr Etud Environm Terr & Planetaires, F-94107 St Maur, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Rice Univ, Dept Phys & Astron, Houston, TX 77251 USA. 9VTT Informat Technol, SW Res Inst, San Antonio, TX 78238 USA. RP Johnson, RE (reprint author), Univ Virginia, Charlottesville, VA 22904 USA. EM rej@virginia.edu RI Cooper, John/D-4709-2012; Smith, Howard/H-4662-2016 OI Smith, Howard/0000-0003-3537-3360 NR 51 TC 59 Z9 59 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 FEB PY 2006 VL 180 IS 2 BP 393 EP 402 DI 10.1016/j.icarus.2005.08.021 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200012 ER PT J AU Palguta, J Anderson, JD Schubert, G Moore, WB AF Palguta, J Anderson, JD Schubert, G Moore, WB TI Mass anomalies on Ganymede SO ICARUS LA English DT Article DE satellites of Jupiter; Ganymede; surfaces; satellite ID GROOVED TERRAIN; WATER VOLCANISM; HIGH-RESOLUTION; DARK TERRAIN; BRIGHT AB Radio Doppler data, generated with NASA's Galileo spacecraft during its second encounter with Jupiter's moon Ganymede, are used to infer the locations and magnitudes of mass anomalies on Ganymede. We construct models for both surface and buried anomalies. With only one flyby and no global coverage, a solution for mass anomalies cannot be uniquely determined. However, we are able to constrain acceptable solutions for mass anomalies to four broad regions-a near polar region and three that are roughly equatorial. If the mass anomalies are constrained to lie at the surface, the centers of the regions are located near the coordinates (77 degrees N7 333 degrees W), (36 degrees N, 0 degrees W) (33 degrees N, 130 degrees W), and (7 degrees N, 194 degrees W). If the mass anomalies are located at the deep ice-rock interface 800 km below the surface, the regions' centers are approximately (65 degrees N, 17 degrees W), (32 degrees N, 30 degrees W), (37 degrees N, 175 degrees W), and (15 degrees N, 211 degrees W). For both models, the regions are up to a few thousand kilometers across. The magnitude of mass anomalies on the surface is on the order of 10(17) kg. Mass anomalies at the ice-rock interface are on average no more than an order of magnitude larger (10(18) kg). There are two positive and two negative mass anomalies in both the surface and ice-rock interface models. One of the positive mass anomalies at the surface is associated with Galileo Regio. The other positive surface mass anomaly is located at high northern latitudes with no obvious geological association. Negative surface mass anomalies lie near Uruk Sulcus and between Perrine Regio and Barnard Regio near Sicyan Sulcus and Phrygia Sulcus. The locations of the ice-rock interface mass anomalies lie approximately radially below the surface anomalies. Positive mass anomalies at the surface could be associated with the silicate-rich ice or accumulated silicate layers of the dark regions. Negative mass anomalies at the surface could be associated with the relatively clean, low-lying ice of sulci. Alternatively, Ganymede's mass anomalies could be associated with the topography or other mass concentrations at the deep ice-rock interface. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Palguta, J (reprint author), Univ Calif Los Angeles, Dept Earth & Space Sci, 3806 Geol, Los Angeles, CA 90095 USA. EM jpalguta@ucla.edu NR 19 TC 14 Z9 14 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 FEB PY 2006 VL 180 IS 2 BP 428 EP 441 DI 10.1016/j.icarus.2005.08.020 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200015 ER PT J AU Vilas, F Lederer, SM Gill, SL Jarvis, KS Thomas-Osip, JE AF Vilas, F Lederer, SM Gill, SL Jarvis, KS Thomas-Osip, JE TI Aqueous alteration affecting the irregular outer planets satellites: Evidence from spectral reflectance SO ICARUS LA English DT Article DE Jovian satellites; Saturnian satellites; Uranian satellites; satellites; irregular; photometry; Neptunian satellites; asteroids ID 8-COLOR ASTEROID SURVEY; JOVIAN-SATELLITES; MU-M; PHOTOMETRIC PROPERTIES; SPECTROSCOPIC SURVEY; TROJAN ASTEROIDS; MAIN-BELT; PHOEBE; WATER; SPECTROPHOTOMETRY AB The surface reflectance properties of the irregular outer planets satellites are probed for evidence for the presence of aqueous alteration products on their surfaces using the strong correlation between the 3.0-mu m water of hydration absorption feature and the 0.7-mu m Fe2+ -> Fe3+ oxidized iron feature seen in low-albedo asteroid reflectances, in an effort to expand our understanding of the composition of the precursor bodies from which the dynamical satellite clusters are derived. Equations converting Johnson V and Kron-Cousins RI photometry to Eight Color Asteroid Survey v (0.550 mu m), w (0.701 mu m), and x (0.853 mu m) photometry are derived from relationships defined by Howell (1995, Ph.D. thesis), and coupled with an algorithm previously defined to detect the presence of the 0.7-mu m absorption feature in ECAS asteroid photometry [Vilas, F., 1994. Icarus 111, 456-467]. Broadband VRI photometry of Ch-class Asteroid 19 Fortuna acquired during 2004 confirms the efficacy of this method of identifying the presence of the 0.7-mu m feature. Photometric observations of many recently discovered irregular outerjovian, saturnian, uranian, and neptunian satellites, coupled with limited asteroid spectroscopy, were examined for the presence of aqueous alteration. The dynamical clusters of outer irregular jovian satellites are mixed between objects that do and do not show this absorption feature. Multiple observations of some objects test both positively and negatively, similar to the Surface variegation that has been observed among many C-class asteroids in the main asteroid belt. Evidence for aqueous alteration on these jovian satellites augers for an origin in or near the same location as the asteroids now occupying the aqueous alteration zone (2.6-3.5 AU), at heliocentric distances internal to Jupiter's orbit. Among the saturnian irreagular satellites, only S IX Phoebe shows limited evidence of aqueous alteration from ground-based observations. The other satellites show no sign of this feature, and have general reflectance properties very similar to the D-class asteroids, Supporting an origin for their precursor bodies in the outer Solar System, perhaps the Centaur region. Only two uranian satellites were tested: U XVII Caliban tests positively for the feature. The differences in surface reflectance properties support the idea that Caliban and U XVI Sycorax derive from separate parent bodies. One observation of neptunian satellite N II Nereid shows no sign of this absorption feature. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr KR, Planetary Astron Grp, Houston, TX 77058 USA. Calif State Univ San Bernardino, Dept Phys, San Bernardino, CA 92407 USA. Lockheed Martin Space Operat, Houston, TX 77058 USA. Observ Carnegie Inst Washington, Observ Las Campanas, La Serena, Chile. RP Vilas, F (reprint author), Univ Arizona, MMT Observ, POB 210065, Tucson, AZ 85721 USA. EM fvilas@mmto.org NR 49 TC 6 Z9 6 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 0019-1035 J9 ICARUS JI Icarus PD FEB PY 2006 VL 180 IS 2 BP 453 EP 463 DI 10.1016/j.icarus.2005.10.004 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 009DT UT WOS:000235092200017 ER PT J AU Lohn, JD Hornby, GS AF Lohn, Jason D. Hornby, Gregory S. TI Evolvable hardware - Using evolutionary computation to design and optimize hardware systems SO IEEE COMPUTATIONAL INTELLIGENCE MAGAZINE LA English DT Article ID GENERATIVE REPRESENTATIONS; ROBOTS AB Evolvable hardware lies at the intersection of evolutionary computation and physical design. Through the use of evolutionary computation methods, the field seeks to develop a variety of technologies that enable automatic design, adaptation, and reconfiguration of electrical and mechanical hardware systems in ways that outperform conventional techniques. This article surveys evolvable hardware with emphasis on some of the latest developments, many of which deliver performance exceeding traditional methods. As such, the field of evolvable hardware is just now starting to emerge from the research laboratory and into mainstream hardware applications. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Lohn, JD (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 43 TC 25 Z9 31 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1556-603X EI 1556-6048 J9 IEEE COMPUT INTELL M JI IEEE Comput. Intell. Mag. PD FEB PY 2006 VL 1 IS 1 BP 19 EP 27 DI 10.1109/MCI.2006.1597058 PG 9 WC Computer Science, Artificial Intelligence SC Computer Science GA 168KK UT WOS:000246523300004 ER PT J AU Anagnostou, DE Zheng, GZ Chryssomallis, MT Lyke, JC Ponchak, GE Papapolymerou, J Christodoulou, CG AF Anagnostou, DE Zheng, GZ Chryssomallis, MT Lyke, JC Ponchak, GE Papapolymerou, J Christodoulou, CG TI Designg fabrication, and measurements of an RF-MEMS-based self-similar reconfigurable antenna SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE fractal; reconfigurable antennas; RF-MEMS; self-similar; Sierpinski; silicon ID SIERPINSKI MONOPOLE ANTENNA AB Reconfigurability in an antenna system is a desired characteristic that has been the focus of much research in recent years. In this work, ohmic contact cantilever RF-MEMS switches are integrated with self-similar planar antennas to provide a reconfigurable antenna system that radiates similar patterns over a wide range of frequencies. The different issues encountered during the integration of the MEMS switches and the overall system design procedure are described herein. The final model radiates at three widely separated frequencies with very similar radiation patterns. The proposed concept can be extended to reconfigurable linear antenna arrays or to more complex antenna structures with large improvements in antenna performance. C1 Univ New Mexico, Albuquerque, NM 87106 USA. Georgia Inst Technol, Atlanta, GA 30308 USA. Democritus Univ Thrace, Polytech Sch, GR-67100 Xanthi, Greece. USAF, Res Lab, Kirtland AFB, NM 87117 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Anagnostou, DE (reprint author), Georgia Inst Technol, Atlanta, GA 30308 USA. EM danagn@ieee.org RI Anagnostou, Dimitris/A-3124-2009; OI Anagnostou, Dimitris/0000-0003-4266-0309; Chryssomallis, MIchael/0000-0002-3319-0096 NR 19 TC 105 Z9 108 U1 0 U2 14 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD FEB PY 2006 VL 54 IS 2 BP 422 EP 432 DI 10.1109/TAP.2005.863399 PN 1 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 015EY UT WOS:000235535900014 ER PT J AU Nikolaou, S Bairavasubramanian, R Lugo, C Carrasquillo, I Thompson, DC Ponchak, GE Papapolymerou, J Tentzeris, MM AF Nikolaou, S Bairavasubramanian, R Lugo, C Carrasquillo, I Thompson, DC Ponchak, GE Papapolymerou, J Tentzeris, MM TI Pattern and frequency reconfigurable annular slot antenna using PIN diodes SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE annular slot antenna (ASA); frequency reconfigurability; pin diode; reconfigurable antenna; reconfigurable radiation; pattern; slot antenna AB This paper presents the use of pin diodes to reconfigure the impedance match and modify the radiation pattern of an annular slot antenna (ASA). The planar antenna is fabricated on one side of a Duroid substrate and the microstrip feeding line with the matching network is fabricated on the opposite side of the board. The central frequency is 5.8 GHz and, by reconfiguring the matching circuit, the antenna was also designed to operate at 5.2 and 6.4 GHz. Pin diodes are also used to short the ASA in preselected positions along the circumference, thereby changing the direction of the null in the plane defined by the circular slot changes. As a proof of concept, two pin diodes are placed 45 degrees on both sides of the feeding line along the ASA and the direction of the null is shown to align with the direction defined by the circular slot center and the diode. Consequently, a design that is reconfigurable in both frequency and radiation pattern is accomplished. Return loss and radiation pattern measurements and simulations are presented, which are in very good agreement. C1 Georgia Inst Technol, Atlanta, GA 30332 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Nikolaou, S (reprint author), Georgia Inst Technol, Atlanta, GA 30332 USA. EM simos@ece.gatech.edu; george.ponchak@ieee.org NR 27 TC 117 Z9 123 U1 3 U2 19 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD FEB PY 2006 VL 54 IS 2 BP 439 EP 448 DI 10.1109/TAP.2005.863398 PN 1 PG 10 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 015EY UT WOS:000235535900016 ER PT J AU Zhou, LS Jung, SY Brandon, E Jackson, TN AF Zhou, LS Jung, SY Brandon, E Jackson, TN TI Flexible substrate micro-crystalline silicon and gated amorphous silicon strain sensors SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE flexible electronics; strain sensors; semiconductor devices; strain measurement; thin films; thin-film transistors (TFTs) AB We present two different kinds of semiconductor strain sensors: ungated n+ micro-crystalline silicon (n + mu C-Si), and gated hydrogenated amorphous silicon (a-Si:H). Both sensor types are fabricated on flexible polyimide substrates. The sensors were characterized with bending perpendicular, parallel, and at 450 with respect to the sensor bias direction, and for several bending diameters. Sensor size and power consumption are significantly reduced compared to metallic foil strain sensors. Small sensor size and ease of integration with a-Si:H thin-film transistors also allows arrays of strain sensors or combinations of strain sensors with varying geometric orientation to allow strain direction as well as magnitude to be unambiguously determined. Index Terms-Flexible electronics, strain sensors, semiconductor devices, strain measurement, thin films, thin-film transistors (TFTs). C1 Penn State Univ, Dept Elect Engn, Ctr Thin Film Devices, University Pk, PA 16802 USA. Penn State Univ, Dept Elect Engn, Mat Res Inst, University Pk, PA 16802 USA. CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. RP Zhou, LS (reprint author), Penn State Univ, Dept Elect Engn, Ctr Thin Film Devices, University Pk, PA 16802 USA. EM Lizl@psu.edu RI Jackson, Thomas/A-4224-2012 NR 8 TC 40 Z9 41 U1 2 U2 14 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 FEB PY 2006 VL 53 IS 2 BP 380 EP 385 DI 10.1109/TED.2005.861727 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 005UX UT WOS:000234850600026 ER PT J AU Sun, W Cetin, M Thacker, WC Chin, TM Willsky, AS AF Sun, W Cetin, M Thacker, WC Chin, TM Willsky, AS TI Variational approaches on discontinuity localization and field estimation in sea surface temperature and soil moisture SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE curve evolution; image segmentation; image smoothing; interpolation; level sets; Mumford-Shah functional; sea surface temperature (SST); soil moisture ID REMOTE-SENSING FOOTPRINTS; ACTIVE CONTOURS; OBJECTIVE ANALYSIS; CROSS-VALIDATION; GULF-STREAM; SPLINE FUNCTIONS; OCEANIC FRONTS; KALMAN FILTER; MODEL; ASSIMILATION AB Some applications in remote sensing require estimating a field containing a discontinuity whose exact location is a priori unknown. Such fields of interest include sea surface temperature in oceanography and soil moisture in hydrology. For the former, oceanic fronts form a temperature discontinuity, while in the latter sharp changes exist across the interface between soil types. To complicate the estimation process, remotely sensed measurements often exhibit regions of missing observations due to occlusions such as cloud cover. Similarly, water surface and ground-based sensors usually provide only an incomplete set of measurements. Traditional methods of interpolation and smoothing for estimating the fields from such potentially sparse measurements often blur across the discontinuities in the field. C1 MIT, Informat & Decis Syst Lab, Cambridge, MA 02139 USA. NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Microsoft Corp, Redmond, WA 98052 USA. EM waltsun@alum.mit.edu RI Thacker, Carlisle/I-3813-2013 OI Thacker, Carlisle/0000-0002-9285-8826 NR 90 TC 2 Z9 2 U1 0 U2 6 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 FEB PY 2006 VL 44 IS 2 BP 336 EP 350 DI 10.1109/TGRS.2005.861012 PG 15 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 006MX UT WOS:000234902700009 ER PT J AU Jackson, BD de Lange, G Zijlstra, T Kroug, M Kooi, JW Stern, JA Klapwijk, TM AF Jackson, BD de Lange, G Zijlstra, T Kroug, M Kooi, JW Stern, JA Klapwijk, TM TI Low-noise 0.8-0.96-and 0.96-1.12-THz superconductor-insulator-superconductor mixers for the Herschel space observatory SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE astronomical satellites; niobium; niobium compounds; radio astronomy; submillimeter-wave mixers; superconductor-insulator-superconductor (SIS) mixers ID TUNNEL-JUNCTION MIXERS; TUNING CIRCUITS; SIS MIXERS; SHOT-NOISE; MILLIMETER; RECEIVER; GHZ AB Heterodyne mixers incorporating Nb SIS junctions and NbTiN-SiO2-Al microstrip tuning circuits offer the lowest reported receiver noise temperatures to date in the 0.8-0.96- and 0.96-1.12-THz frequency bands. In particular, improvements in the quality of the NbTiN ground plane of the SIS devices' on-chip microstrip tuning circuits have yielded significant improvements in the sensitivity of the 0.96-1.12-THz mixers relative to previously presented results. Additionally, an optimized RF design incorporating a reduced-height waveguide and suspended stripline RF choke filter offers significantly larger operating bandwidths than were obtained with mixers that incorporated full-height waveguides near 1 THz. Finally, the impact of junction current density and quality on the performance of the 0.84.96-THz mixers is discussed and compared with measured mixer sensitivities, as are the relative sensitivities of the 0.8-0.96- and 0.96-1.12-THz mixers. C1 SRON, Natl Inst Space Res, NL-9747 AD Groningen, Netherlands. Delft Univ Technol, Fac Sci Appl, Kavli Inst Nanosci, NL-2628 CJ Delft, Netherlands. CALTECH, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Jackson, BD (reprint author), SRON, Natl Inst Space Res, NL-9747 AD Groningen, Netherlands. EM B.D.Jackson@sron.rug.nl; G.de.Lange@sron.rug.nl; zijlstra@dimes.tudelft.nl; kroug@dimes.tudelft.nl; kooi@submm.caltech.edu; Jeffrey.Stern@jpl.nasa.gov; t.m.klapwijk@tnw.tudelft.nl NR 29 TC 38 Z9 39 U1 0 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD FEB PY 2006 VL 54 IS 2 BP 547 EP 558 DI 10.1109/TMTT.2005.862717 PN 1 PG 12 WC Engineering, Electrical & Electronic SC Engineering GA 011VJ UT WOS:000235296300005 ER PT J AU Rubiola, E Salik, E Yu, N Maleki, L AF Rubiola, E Salik, E Yu, N Maleki, L TI Flicker noise in high-speed p-i-n photodiodes SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE noise measurement; optical fiber devices; optical modulation; phase noise; p-i-n photodiodes ID PHASE-NOISE; MICROWAVE SIGNALS; FEMTOSECOND-LASER; OPTICAL LINKS; AMPLITUDE; OSCILLATOR; SYSTEMS AB The microwave signal at the output of a photodiode that detects a modulated optical beam contains the phase noise rho(t) and amplitude noise alpha(t) of the detector. Beside the white noise, which is well understood, the spectral densities S-rho(f) and S-alpha(f) show flicker noise proportional to 1/f. We report on the measurement of the phase and amplitude noise of high-speed p-i-n photodiodes. The main result is that the flicker coefficient of the samples is similar to 10(-12) rad(2)/Hz (-120 dBrad(2)/Hz) for phase noise, and similar to 10(-12) Hz(-1) (-120 dB) for amplitude noise. These values could be observed only after solving a number of experimental problems and in a protected environment. By contrast, in ordinary conditions, insufficient electromagnetic interference isolation, and also insufficient mechanical isolation, are responsible for additional noise to be taken in. This suggests that if package and electromagnetic compatibility are revisited, applications can take the full benefit from the surprisingly low noise of the p-i-n photodiodes. C1 Univ Franche Comte, CNRS, UMR 6164, FEMTO ST,LPMO, F-25044 Besancon, France. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Univ Franche Comte, CNRS, UMR 6164, FEMTO ST,LPMO, F-25044 Besancon, France. NR 27 TC 22 Z9 22 U1 0 U2 7 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 FEB PY 2006 VL 54 IS 2 BP 816 EP 820 DI 10.1109/TMTT.2005.863062 PN 2 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA 011VK UT WOS:000235296400007 ER PT J AU Campbell, CL Peters, RA Bodenheimer, RE Bluethmann, WJ Huber, E Ambrose, RO AF Campbell, CL Peters, RA Bodenheimer, RE Bluethmann, WJ Huber, E Ambrose, RO TI Superpositioning of behaviors learned through teleoperation SO IEEE TRANSACTIONS ON ROBOTICS LA English DT Article DE dexterous manipulators; intelligent robots; nonlinear functions; robot programming; telerobotics ID ROBOTS AB This paper reports that the superposition of a small set of behaviors, learned via teleoperation, can lead to robust completion of an articulated reach-and-grasp task. The results support the hypothesis that a robot can learn to interact purposefully with its environment through a developmental acquisition of sensory-motor coordination. Teleoperation can bootstrap the process by enabling the robot to observe its own sensory responses to actions that lead to specific outcomes within an environment. It is shown that a reach-and-grasp task, learned by an articulated robot through a small number of teleoperated trials, can be performed autonomously with success in the face of significant variations in the environment and perturbations of the goal. In particular, teleoperation of the robot to reach and grasp an object at nine different locations in its workspace enabled robust autonomous performance of the task anywhere within the workspace. Superpositioning was performed using the Verbs and Adverbs algorithm that was developed originally for the graphical animation of articulated characters. The work was performed on Robonaut, the NASA space-capable humanoid at Johnson Space Center, Houston, TX. C1 Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Vanderbilt Univ, Dept Elect Engn & Comp Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. EM christina.l.campbell@vanderbilt.edu; Alan.Peters@vanderbilt.edu; bobbyb@vuse.vanderbilt.edu; william.j.bluethmann1@jsc.nasa.gov; eric@roboteyes.com; robert.o.ambrose@nasa.gov NR 27 TC 11 Z9 11 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1552-3098 EI 1941-0468 J9 IEEE T ROBOT JI IEEE Trans. Robot. PD FEB PY 2006 VL 22 IS 1 BP 79 EP 91 DI 10.1109/TRO.2005.861485 PG 13 WC Robotics SC Robotics GA 014OZ UT WOS:000235490800008 ER PT J AU Pan, L Zhang, WH Asuncion, A Lai, MK Dillencourt, MB Bic, LF Yang, LT AF Pan, L Zhang, WH Asuncion, A Lai, MK Dillencourt, MB Bic, LF Yang, LT TI Toward incremental parallelization using navigational programming SO IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS LA English DT Article DE programming methodologies; incremental parallelization; navigational programming (NavP); program transformation; matrix multiplication; gentleman's algorithm; cannon's algorithm AB The Navigational Programming (NavP) methodology is based on the principle of self-migrating computations. It is a truly incremental methodology for developing parallel programs: each step represents a functioning program, and each intermediate program is an improvement over its predecessor. The transformations are mechanical and straightforward to apply. We illustrate our methodology in the context of matrix multiplication, showing how the transformations lead from a sequential program to a fully parallel program. The NavP methodology is conducive to new ways of thinking that lead to ease of programming and high performance. Even though our parallel algorithm was derived using a sequence of mechanical transformations, it displays certain performance advantages over the classical handcrafted Gentleman's Algorithm. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Irvine, Donald Bren Sch Informat & Comp Sci, Irvine, CA 92697 USA. St Francis Xavier Univ, Dept Comp Sci, Antigonish, NS B2G 2W5, Canada. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Lei.Pan@jpl.nasa.gov NR 14 TC 1 Z9 1 U1 0 U2 1 PU IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG PI TOKYO PA KIKAI-SHINKO-KAIKAN BLDG, 3-5-8, SHIBA-KOEN, MINATO-KU, TOKYO, 105-0011, JAPAN SN 1745-1361 J9 IEICE T INF SYST JI IEICE Trans. Inf. Syst. PD FEB PY 2006 VL E89D IS 2 BP 390 EP 398 DI 10.1093/ietisy/e89-d.2.390 PG 9 WC Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA 014VP UT WOS:000235508800002 ER PT J AU Choi, SR Nemeth, NN Gyekenyesi, JP AF Choi, SR Nemeth, NN Gyekenyesi, JP TI Slow crack growth of brittle materials with exponential crack velocity under cyclic fatigue loading SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article DE slow crack growth; crack-velocity formulation; power-law crack velocity; exponential crack velocity; life prediction; advanced ceramics; fatigue testing ID INDENTATION FLAWS; SILICON-NITRIDE; PROPAGATION; ALUMINA; BEHAVIOR; GLASS AB The life prediction analysis to determine life as a function of applied stress for brittle materials was made numerically based on an exponential crack velocity formulation. The results were examined using the experimental data on advanced structural ceramics tested under cyclic fatigue loading at ambient and elevated temperatures. The data fit to the obtained relation of In(time to failure) versus maximum applied stress was very reasonable and compares well with that of the more widely utilized power-law crack velocity. It was also found that life prediction from one loading configuration (static fatigue) to another (cyclic fatigue) in the exponential formulation resulted in a similar degree of accuracy as compared with that in the power-law formulation. The major limitation in the exponential crack-velocity formulation, however, was that inert strength of a material must be known priori to evaluate the important slow-crack-growth parameter n, a significant drawback/burden as compared with the conventional power-law crack-velocity formulation. (c) 2005 Elsevier Ltd. All rights reserved. C1 Glenn Res Ctr, NASA, Cleveland, OH 44135 USA. RP Choi, SR (reprint author), Glenn Res Ctr, NASA, 2100 Brookpk Rd, Cleveland, OH 44135 USA. EM sung.r.choi@grc.nasa.gov NR 27 TC 7 Z9 7 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD FEB PY 2006 VL 28 IS 2 BP 164 EP 172 DI 10.1016/j.ijfatigue.2005.03.007 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 993IB UT WOS:000233946700009 ER PT J AU Leatherbarrow, EL Harper, JV Cucinotta, FA O'Neill, P AF Leatherbarrow, EL Harper, JV Cucinotta, FA O'Neill, P TI Induction and quantification of gamma-H2AX foci following low and high LET-irradiation SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article DE gamma-H2AX foci; DNA double strand break; alpha-irradiation; gamma-irradiation; V79-4 ID DOUBLE-STRAND BREAKS; PHOSPHORYLATED HISTONE H2AX; HEAT-LABILE SITES; DNA-DAMAGE; MAMMALIAN-CELLS; REPAIR; RADIATION; EXPRESSION; DEFICIENT; SENSITIVITY AB Purpose: To investigate quantitatively the induction and rejoining of DNA double strand breaks (DSB) in V79-4 and xrs-5 Chinese hamster cells and HF19 human fibroblast cells, using the phosphorylation of the histone protein H2AX (gamma-H2AX) as an indicator of DSB, exposed to low doses of either low linear energy transfer (LET) Co-60 gamma-rays or high LET alpha-particles. Materials and methods: Cells were irradiated with low or high LET ( 20 - 2000 mGy). The gamma-H2AX foci were detected using immunohistochemistry and quantified by image analysis. Results: The number of DSB determined 30 min post gamma-irradiation at 37 degrees C is 12.2 (+/- 1.5), 13.5 (+/- 1.6) and 19.1 (+/- 1.7) foci/cell/ Gy for V79-4, xrs- 5 and HF19 cells respectively, comparable with levels detected in V79-4 cells using pulse field gel electrophoresis. 6 h post gamma-irradiation, gamma-H2AX foci levels in V79-4 and HF19 cells approach control levels but remain higher in DSB repair deficient xrs- 5 cells. gamma-H2AX foci levels remain significantly higher than controls at 6 h in alpha-irradiated cells. Conclusions: gamma-radiation and alpha-radiation induced the phosphorylation of H2AX in response to DSB at low doses; the variation in the rate of dephosphorylation of induced foci are dependent both on radiation quality and cell characteristics. C1 MRC, Radiat & Genome Stabil Unit, DNA Damage Grp, Didcot OX11 0RD, Oxon, England. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP O'Neill, P (reprint author), MRC, Radiat & Genome Stabil Unit, DNA Damage Grp, Didcot OX11 0RD, Oxon, England. EM p.oneill@har.mrc.ac.uk FU Medical Research Council [G0700730] NR 28 TC 111 Z9 120 U1 0 U2 6 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 FEB PY 2006 VL 82 IS 2 BP 111 EP 118 DI 10.1080/09553000600599783 PG 8 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 022SK UT WOS:000236075900005 PM 16546909 ER PT J AU Denney, E Fischer, B Schumann, J AF Denney, E Fischer, B Schumann, J TI An empirical evaluation of automated theorem provers in software certification SO INTERNATIONAL JOURNAL ON ARTIFICIAL INTELLIGENCE TOOLS LA English DT Article; Proceedings Paper CT Workshop on Empirically Successful First Order Reasoning (ESFOR) CY 2004 CL Cork, IRELAND DE software certification; automated theorem proving; program synthesis; proof checking; traceability; verification condition generator; Hoare logic ID SYSTEM; COMPETITION AB We describe a system for the automated certification of safety properties of NASA software. The system uses Hoare-style program verification technology to generate proof obligations which are then processed by an automated first-order theorem prover (ATP). We discuss the unique requirements this application places on the ATPs, focusing on automation, proof checking, traceability, and usability, and describe the resulting system architecture, including a certification browser that maintains and displays links between obligations and source code locations, For full automation, the obligations must be aggressively preprocessed and simplified, and we demonstrate how the individual simplification stages, which are implemented by rewriting, influence the ability of the ATPs to solve the proof tasks. Our results are based on 13 comprehensive certification experiments that lead to 366 top-level safety obligations and ultimately to more than 25,000 proof tasks which have been used to determine the suitability of the high-performance provers DCTP, E-Setheo, E, Gandalf, Otter, Setheo, Spass, and Vampire, and our associated infrastructure. The proofs found by Otter have been checked by Ivy. C1 NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. RP NASA, Ames Res Ctr, RIACS, M-S 269-2, Moffett Field, CA 94035 USA. EM edenney@email.arc.nasa.gov; fisch@email.arc.nasa.gov; schumann@email.arc.nasa.gov NR 51 TC 3 Z9 3 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0218-2130 EI 1793-6349 J9 INT J ARTIF INTELL T JI Int. J. Artif. Intell. Tools PD FEB PY 2006 VL 15 IS 1 BP 81 EP 107 DI 10.1142/S0218213006002576 PG 27 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA 008UO UT WOS:000235066400005 ER PT J AU Benford, J Benford, G Kuiper, T AF Benford, J Benford, G Kuiper, T TI Max-microwave acceleration experiment with Cosmos-1 SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article; Proceedings Paper CT 4th Symposium on Realistic Near-Term Advanced Scientific Space Missions CY JUL 04-06, 2005 CL Aosta, ITALY SP Int Acad Austronaut DE beam driven sail; solar sail; Cosmos-1 ID SUN-DIVER; DESORPTION; MISSIONS AB The Planetary Society planned to launch Cosmos-1, the first solar sail in 2005. We planned an experiment to irradiate the sail with the Deep Space Network beam Goldstone Solar System Radar. This could demonstrate, for the first time, beamed propulsion of a sail in space. This can demonstrate, for the first time, beamed propulsion of a sail in space. The 450 kW microwave beam from the large 70-m dish can provide direct microwave beam acceleration of the sail by photon pressure. We can measure that acceleration by telemetry from on-board accelerometers. We planned to modulate the beam to excite resonant oscillatory modes of the sail, enhancing the signal-to-noise ratio. We discuss issues affecting this experiment: how to track the sail and put the beam on it, download the accelerometer data and analyze it. C1 Microwave Sci Inc, Lafayette, CA 94549 USA. Univ Calif Irvine, Dept Phys, Irvine, CA 92697 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Benford, J (reprint author), Microwave Sci Inc, 1041 Los Arabis Lane, Lafayette, CA 94549 USA. NR 5 TC 2 Z9 3 U1 1 U2 1 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD FEB PY 2006 VL 59 IS 2 BP 68 EP 70 PG 3 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 007NH UT WOS:000234975900007 ER PT J AU Gruntman, M McNutt, RL Gold, RE Krimigis, SM Roelof, EC Leary, JC Gloeckler, G Koehn, PL Kurth, WS Oleson, SR Fiehler, D AF Gruntman, M McNutt, RL Gold, RE Krimigis, SM Roelof, EC Leary, JC Gloeckler, G Koehn, PL Kurth, WS Oleson, SR Fiehler, D TI Innovative explorer mission to interstellar space SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article; Proceedings Paper CT 4th IAA Symposium on Realistic Near-Term Advanced Scientific Space Missions CY JUL 04-06, 2005 CL Aosta, ITALY SP Int Acad Austronaut DE interstellar space; interstellar mission; interstellar medium; RTG; electric propulsion ID SOLAR-WIND; REGION AB A mission to interstellar space has been under discussion for over 25 years. Many fundamental scientific questions about the nature of the surrounding galactic medium and its interaction with the solar system can only be answered by in situ measurements that such a mission would provide. The technical difficulties and budgetary and programmatic realities have prevented implementation of previous studies based oil the use of a near-Sun perihelion propulsive maneuver, solar sails, and large fission-reactor-powered nuclear electric propulsion systems. We present ail alternative approach - the Innovative Interstellar Explorer - based on Radioisotope Electric Propulsion. A high-energy, current-technology launch of the small spacecraft is followed by long-term, lowthrust, continuous acceleration enabled by a kilowatt-class ion thruster powered by Pu-238 Stirling radioisotope generators. We describe the science, payload, and mission and spacecraft design. We also discuss the role such a mission plays in assessing heliospheric "space climate," knowledge of which is vital for human exploration to Mars and beyond. C1 Univ So Calif, Astronaut & Space Technol Div, Los Angeles, CA 90089 USA. Johns Hopkins Univ, Appl Phys Lab, Dept Space, Laurel, MD 20723 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. NASA, Glenn Res Ctr, QSS Grp Inc, Cleveland, OH 44135 USA. RP Gruntman, M (reprint author), Univ So Calif, Astronaut & Space Technol Div, Los Angeles, CA 90089 USA. EM mikeg@usc.edu RI McNutt, Ralph/E-8006-2010; Gruntman, Mike/A-5426-2008; OI McNutt, Ralph/0000-0002-4722-9166; Gruntman, Mike/0000-0002-0830-010X; Kurth, William/0000-0002-5471-6202 NR 30 TC 2 Z9 2 U1 0 U2 1 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD FEB PY 2006 VL 59 IS 2 BP 71 EP 75 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 007NH UT WOS:000234975900008 ER PT J AU Lee, YC Savtchenko, A AF Lee, YC Savtchenko, A TI Relationship between air pollution in Hong Kong and in the Pearl River Delta region of south China in 2003 and 2004: An analysis SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article AB Air pollution in the Pearl River Delta (PRD) region of south China, which is one of the four regions in China most heavily affected by haze, is found to correlate with that of Hong Kong, indicating the regional nature of the Hong Kong problem. Of the 10 territory-wide episode days occurring in Hong Kong in 2003 and 2004, 3 of them coincide with the most polluted days of the month in the PRD. On two other episode days, the most polluted days in the PRD occurred within 2 days of the Hong Kong episodes. The air pollution trends of the PRD cities and Hong Kong are found to resemble each other more under certain meteorological conditions than others, notably when a tropical storm is positioned at the Luzon Strait between Taiwan and Luzon in the Philippines, and the entire PRD, including Hong Kong, is equally affected by it, resulting in photochemical events. During this time, Hong Kong is downwind of nearly all pollution sources in the region. At other positions of the storm, the eastern part of the PRD is often affected more significantly. In winter episodic conditions, which occur when weak anticyclones prevail over south China, local meteorological factors, namely, inversions and sea-breeze convergences, are believed to contribute to the temporal difference of the pollution peaks in Hong Kong and the rest of the PRD. C1 Green Council, Hong Kong, Hong Kong, Peoples R China. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lee, YC (reprint author), Green Council, New World Tower 1,18 Queens Rd Cent, Hong Kong, Hong Kong, Peoples R China. EM ycleec@netvigator.com NR 19 TC 12 Z9 13 U1 0 U2 5 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 FEB PY 2006 VL 45 IS 2 BP 269 EP 282 DI 10.1175/JAM2332.1 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 038SM UT WOS:000237244000003 ER PT J AU Whiteman, DN Demoz, B Di Girolamo, P Comer, J Veselovskii, I Evans, K Wang, Z Cadirola, M Rush, K Schwemmer, G Gentry, B Melfi, SH Mielke, B Venable, D Van Hove, T AF Whiteman, DN Demoz, B Di Girolamo, P Comer, J Veselovskii, I Evans, K Wang, Z Cadirola, M Rush, K Schwemmer, G Gentry, B Melfi, SH Mielke, B Venable, D Van Hove, T TI Raman lidar measurements during the International H2O Project. Part I: Instrumentation and analysis techniques SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID WATER-VAPOR LIDAR; BACKSCATTER; TEMPERATURE; PROFILES; PERFORMANCE; CALIBRATION; RETRIEVALS; EXTINCTION; IHOP-2002; AEROSOLS AB The NASA Goddard Space Flight Center (GSFC) Scanning Raman Lidar (SRL) participated in the International HO Project (IHOP), which occurred in May and June 2002 in the midwestern part of the United States. The SRL received extensive optical modifications prior to and during the IHOP campaign that added new measurement capabilities and enabled unprecedented daytime water vapor measurements by a Raman lidar system. Improvements were also realized in nighttime upper-tropospheric water vapor measurements. The other new measurements that were added to the SRL for the IHOP deployment included rotational Raman temperature, depolarization. cloud liquid water, and citrus cloud ice water content. In this first of two parts, the details of the operational configuration of the SRL during [HOP are provided along with a description of the analysis and calibration procedures for water vapor mixing ratio, aerosol depolarization. and cirrus cloud extinction-to-backscatter ratio. For the first time, a Raman water vapor lidar calibration is performed, taking full account of the temperature sensitivity of water vapor and nitrogen Raman scattering. Part 11 presents case studies that permit the daytime and nighttime error statistics to be quantified. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Basilicata, DIFA, I-85100 Potenza, Italy. Sci Syst Applicat Inc, Lanham, MD USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. Univ Wyoming, Laramie, WY 82071 USA. Ecotronics LLC, Clarksburg, MD USA. Licel Corp, Berlin, Germany. Howard Univ, Washington, DC 20059 USA. Univ Corp Atmospher Res, Boulder, CO USA. RP Whiteman, DN (reprint author), NASA, Goddard Space Flight Ctr, Code 613-1,Bldg 33,Room D404, Greenbelt, MD 20771 USA. EM david.n.whiteman@nasa.gov RI Wang, Zhien/F-4857-2011; Demoz, Belay/N-4130-2014 NR 37 TC 54 Z9 54 U1 2 U2 18 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 FEB PY 2006 VL 23 IS 2 BP 157 EP 169 DI 10.1175/JTECH1838.1 PG 13 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 023EQ UT WOS:000236108900001 ER PT J AU Whiteman, DN Demoz, B Di Girolamo, P Comer, J Veselovskii, I Evans, K Wang, Z Sabatino, D Schwemmer, G Gentry, B Lin, RF Behrendt, A Wulfmeyer, V Browell, E Ferrare, R Ismail, S Wang, J AF Whiteman, DN Demoz, B Di Girolamo, P Comer, J Veselovskii, I Evans, K Wang, Z Sabatino, D Schwemmer, G Gentry, B Lin, RF Behrendt, A Wulfmeyer, V Browell, E Ferrare, R Ismail, S Wang, J TI Raman lidar measurements during the International H2O Project. Part II: Case studies SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID WATER-VAPOR; CIRRUS CLOUDS; PERFORMANCE; SYSTEM; MODEL AB The NASA GSFC Scanning Raman Lidar (SRL) participated in the International H2O Project (IHOP) that occurred in May and June 2002 in the midwestern part of the United States. The SRL system configuration and methods of data analysis were described in Part I of this paper. In this second part, comparisons of SRL water vapor measurements and those of Lidar Atmospheric Sensing Experiment (LASE) airborne water vapor lidar and chilled-mirror radiosonde are performed. Two case studies are then presented: one for daytime and one for nighttime. The daytime case study is of a convectively driven boundary layer event and is used to characterize the daytime SRL water vapor random error characteristics. The nighttime case study is of a thunderstorm-generated cirrus cloud case that is studied in its meteorological context. Upper-tropospheric humidification due to precipitation from the cirrus cloud is quantified as is the cirrus cloud optical depth, extinction-to-backscatter ratio, ice water content, cirrus particle size, and both particle and volume depolarization ratios. A stability and back-trajectory analysis is performed to study the origin of wave activity in one of the cloud layers. These unprecedented cirrus cloud measurements are being used in a cirrus cloud modeling study. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Basilicata, DIFA, I-85100 Potenza, Italy. Sci Syst Applicat Inc, Lanham, MD USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. Univ Wyoming, Laramie, WY 82071 USA. Univ Hohenheim, Hohenheim, Germany. NASA, Langley Res Ctr, Langley, VA USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. RP Whiteman, DN (reprint author), NASA, Goddard Space Flight Ctr, Code 663-1,Bldg 33,Room D404, Greenbelt, MD 20771 USA. EM david.n.whiteman@nasa.gov RI Wang, Zhien/F-4857-2011; Demoz, Belay/N-4130-2014; OI Behrendt, Andreas/0000-0003-2719-4354 NR 25 TC 27 Z9 27 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 FEB PY 2006 VL 23 IS 2 BP 170 EP 183 DI 10.1175/JTECH1839.1 PG 14 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 023EQ UT WOS:000236108900002 ER PT J AU Riggin, DM Liu, HL Lieberman, RS Roble, RG Russell, JM Mertens, CJ Mlynczak, MG Pancheva, D Franke, SJ Murayama, Y Manson, AH Meek, CE Vincent, RA AF Riggin, DM Liu, HL Lieberman, RS Roble, RG Russell, JM Mertens, CJ Mlynczak, MG Pancheva, D Franke, SJ Murayama, Y Manson, AH Meek, CE Vincent, RA TI Observations of the 5-day wave in the mesosphere and lower thermosphere SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article; Proceedings Paper CT 2nd IAGA/ICMA Workshop on Vertical Coupling in the Atmosphere-Ionosphere System CY JUL 12-15, 2004 CL Univ Bath, Bath, ENGLAND SP Int Assoc Geomagnet & Aeron, Int Commiss Middle Atmosphere, Int Union Geodesy & Geophy, Int Union Radio Sci, USF European Off Aerosp & Dev HO Univ Bath DE planetary wave; 5-day wave; middle atmosphere; thermosphere ID PLANETARY-WAVES; 6.5-DAY WAVE; LONGITUDINAL VARIATIONS; EQUATORIAL MESOSPHERE; RADAR OBSERVATIONS; ZONAL WIND; ATMOSPHERE; OSCILLATIONS; TEMPERATURE; MIDDLE AB The 5-day wave is the gravest symmetric Hough mode of westward propagating zonal wavenumber 1. This wave is observed using the SABER instrument aboard the TIMED satellite during the first three years of the spacecraft mission (2002-2004). Supporting measurements were made with mesospheric radar systems. To better interpret the observations, the NCAR thermosphere-ionosphere-mesosphere-electrodynamics general circulation model (TIME-GCM) simulation of year 2003 is used for comparative analysis. For the simulation the lower boundary was specified using NCEP data. The climatology from SABER shows a May maximum in the amplitude of the 5-day wave, which is consistent with the seasonal dependence found in earlier studies. A particularly strong wave with a similar to 6 day period was observed in May 2003 and is studied in some detail. There is considerable evidence from both data and model in our study that a major source for this wave was in the southern (winter) hemisphere. Cross-equatorial ducting allowed the wave to propagate into the northern (summer) hemisphere, where it was amplified by baroclinic instability. (c) 2005 Elsevier Ltd. All rights reserved. C1 NW Res Associates, Colorado Res Associates Div, Boulder, CO USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO USA. Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Univ Bath, Bath BA2 7AY, Avon, England. Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. Natl Inst Informat & Commun Technol, Appl Res & Stand Dept, Tokyo, Japan. Univ Saskatchewan, Inst Space & Atmospher Studies, Saskatoon, SK S7N 0W0, Canada. Univ Adelaide, Dept Phys, Adelaide, SA 5005, Australia. RP Riggin, DM (reprint author), NW Res Associates, Colorado Res Associates Div, Boulder, CO USA. EM Riggin@colorado-research.com RI Liu, Han-Li/A-9549-2008; Mlynczak, Martin/K-3396-2012 OI Liu, Han-Li/0000-0002-6370-0704; Riggin, Dennis/0000-0001-5094-7620; Murayama, Yasuhiro/0000-0003-1129-334X; NR 36 TC 47 Z9 48 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD FEB PY 2006 VL 68 IS 3-5 BP 323 EP 339 DI 10.1016/j.jastp.2005.05.010 PG 17 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 026AQ UT WOS:000236309500008 ER PT J AU Nguyen, P Vaddiraju, S Meyyappan, M AF Nguyen, P Vaddiraju, S Meyyappan, M TI Indium and tin oxide nanowires by vapor-liquid-solid growth technique SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT Symposium on Application and Fundamentals of High Aspect Ratio Nanomaterials held at the 134th TMS Annual Meeting and Exhibition CY FEB 13-17, 2005 CL San Francisco, CA SP TMS DE inorganic nanowires; vapor-liquid-solid approach; tin oxide; indium oxide; catalyst-assisted growth ID RAY PHOTOELECTRON-SPECTROSCOPY; FIELD-EFFECT TRANSISTOR; SUBSTRATE; MECHANISM; FILMS; SNO2 AB Regular three-dimensional (3-D) arrays of crystalline SnO2-In2O3 nanowires were produced on m-sapphire using a gold catalyst-assisted vapor-liquid-solid growth process. The growth characteristics at multiple growth conditions were analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), x-ray photoemission spectroscopy (XPS), and Rutherford backscattering spectroscopy (RBS) to evaluate the functional dependence of nanowire structure and composition on growth parameters such as temperature and source composition. The results indicate that nanowires of mixed composition are not possible from the catalytic clusters; rather, a mixture of indium and tin oxide wires are formed in the range of conditions investigated here. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Nguyen, P (reprint author), NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM meyya@orbit.arc.nasa.gov NR 19 TC 13 Z9 13 U1 1 U2 10 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD FEB PY 2006 VL 35 IS 2 BP 200 EP 206 DI 10.1007/BF02692436 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 025ZE UT WOS:000236305500004 ER PT J AU Willis, P Berthias, JP Bar-Sever, YE AF Willis, P Berthias, JP Bar-Sever, YE TI Systematic errors in the Z-geocenter derived using satellite tracking data: a case study from SPOT-4 DORIS data in 1998 SO JOURNAL OF GEODESY LA English DT Article DE DORIS; terrestrial reference frame; geocenter variations; precise orbit determination; cross-track correction; SPOT-4 ID TERRESTRIAL REFERENCE FRAME; SURFACE LOADING DATA; SEA-LEVEL; EARTH; PERSPECTIVE; DEFINITION; MOTION AB Within the scope of the Global Geodetic Observing System, Doppler Orbit Determination and Radiopositioning Integrated by Satellite-as a geodetic technique-can provide precise and continuous monitoring of the geocenter motion related to mass redistribution in the Earth, ocean and atmosphere system. We have reanalyzed 1998 DORIS/SPOT-4 (Satellite pour l' Observation de la Terre) data that were previously generating inconsistent geocenter positions (-65 cm offset). We show here that this error is due to an incorrect phase center correction provided with the DORIS preprocessed data resulting from a +12 cm offset in the cross-track direction that has been confirmed since. We also conclude that a 1 mm error in the cross-track offset of non-yawing sun-synchronous SPOT satellites will generate a -6.5 mm error in the derived Z-geocenter. Other non-yawing satellites would also be affected by a similar effect whose amplitude could be easily estimated from the orbit inclination. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Ctr Natl Etud Spatiales, F-31401 Toulouse 9, France. Inst Geog Natl, Direct Tech, F-94160 St Mande, France. RP Willis, P (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Ms 238-600, Pasadena, CA 91109 USA. EM Pascal.R.Willis@jpl.nasa.gov RI Willis, Pascal/A-8046-2008 OI Willis, Pascal/0000-0002-3257-0679 NR 25 TC 27 Z9 27 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0949-7714 J9 J GEODESY JI J. Geodesy PD FEB PY 2006 VL 79 IS 10-11 BP 567 EP 572 DI 10.1007/s00190-005-0013-9 PG 6 WC Geochemistry & Geophysics; Remote Sensing SC Geochemistry & Geophysics; Remote Sensing GA 011LX UT WOS:000235270800001 ER PT J AU Snajdrova, K Boehm, J Willis, P Haas, R Schuh, H AF Snajdrova, K Boehm, J Willis, P Haas, R Schuh, H TI Multi-technique comparison of tropospheric zenith delays derived during the CONT02 campaign SO JOURNAL OF GEODESY LA English DT Article DE troposphere; zenith delay; GPS; VLBI; DORIS; Water Vapor Radiometer ID INTERNATIONAL DORIS SERVICE; WATER-VAPOR; WET DELAYS; PATH DELAY; GPS; SYSTEM; GRADIENTS; VLBI; INTERFEROMETRY; VARIABILITY AB In October 2002, 15 continuous days of Very Long Baseline Interferometry (VLBI) data were observed in the Continuous VLBI 2002 (CONT02) campaign. All eight radio telescopes involved in CONT02 were co-located with at least one other space-geodetic technique, and three of them also with a Water Vapor Radiometer (WVR). The goal of this paper is to compare the tropospheric zenith delays observed during CONT02 by VLBI, Global Positioning System (GPS), Doppler Orbitography Radiopositioning Integrated by Satellite (DORIS) and WVR and to compare them also with operational pressure level data from the European Centre for Medium-Range Weather Forecasts (ECMWF). We show that the tropospheric zenith delays from VLBI and GPS are in good agreement at the 3-7 mm level. However, while only small biases can be found for most of the stations, at Kokee Park (Hawaii, USA) and Westford (Massachusetts, USA) the zenith delays derived by GPS are larger by more than 5 mm than those from VLBI. At three of the four DORIS stations, there is also a fairly good agreement with GPS and VLBI (about 10 mm), but at Kokee Park the agreement is only at about 30 mm standard deviation, probably due to the much older installation and type of DORIS equipment. This comparison also allows testing of different DORIS analysis strategies with respect to their real impact on the precision of the derived tropospheric parameters. Ground truth information about the zenith delays can also be obtained from the ECMWF numerical weather model and at three sites using WVR measurements, allowing for comparisons with results from the space-geodetic techniques. While there is a good agreement (with some problems mentioned above about DORIS) among the space-geodetic techniques, the comparison with WVR and ECMWF is at a lower accuracy level. The complete CONT02 data set is sufficient to derive a good estimate of the actual precision and accuracy of each geodetic technique for applications in meteorology. C1 Vienna Univ Technol, Inst Geodesy & Geophys, A-1040 Vienna, Austria. Brno Univ Technol, Inst Geodesy, Brno 66237, Czech Republic. Inst Geog Natl, Direct Tech, F-94160 St Mande, France. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Chalmers, Dept Radio & Space Sci, Onsala Space Observ, SE-43992 Onsala, Sweden. RP Boehm, J (reprint author), Vienna Univ Technol, Inst Geodesy & Geophys, Gusshausstr 27-29, A-1040 Vienna, Austria. EM ksnajd@mars.hg.tuwien.ac.at; johannes.boehm@tuwien.ac.at; pascal.willis@ign.fr; haas@oso.chalmers.se; harald.schuh@tuwien.ac.at RI Willis, Pascal/A-8046-2008; Haas, Rudiger/G-1286-2010; Bohm, Johannes/H-9161-2013 OI Willis, Pascal/0000-0002-3257-0679; Haas, Rudiger/0000-0003-2681-9228; Bohm, Johannes/0000-0002-1208-5473 NR 52 TC 52 Z9 52 U1 0 U2 5 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0949-7714 J9 J GEODESY JI J. Geodesy PD FEB PY 2006 VL 79 IS 10-11 BP 613 EP 623 DI 10.1007/s00190-005-0010-z PG 11 WC Geochemistry & Geophysics; Remote Sensing SC Geochemistry & Geophysics; Remote Sensing GA 011LX UT WOS:000235270800005 ER PT J AU Schmid, B Ferrare, R Flynn, C Elleman, R Covert, D Strawa, A Welton, E Turner, D Jonsson, H Redemann, J Eilers, J Ricci, K Hallar, AG Clayton, M Michalsky, J Smirnov, A Holben, B Barnard, J AF Schmid, B Ferrare, R Flynn, C Elleman, R Covert, D Strawa, A Welton, E Turner, D Jonsson, H Redemann, J Eilers, J Ricci, K Hallar, AG Clayton, M Michalsky, J Smirnov, A Holben, B Barnard, J TI How well do state-of-the-art techniques measuring the vertical profile of tropospheric aerosol extinction compare? SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID COLUMNAR WATER-VAPOR; MID-ATLANTIC COAST; RADIATION MEASUREMENT PROGRAM; AIRBORNE SUN PHOTOMETER; SOUTHERN GREAT-PLAINS; OPTICAL-DEPTH SPECTRA; REMOTE-SENSING MEASUREMENTS; GROUND-BASED MEASUREMENTS; PARTICULATE BLACK CARBON; SINGLE-SCATTERING ALBEDO AB [1] The recent Department of Energy Atmospheric Radiation Measurement (ARM) Aerosol Intensive Operations Period (AIOP, May 2003) yielded one of the best measurement sets obtained to date to assess our ability to measure the vertical profile of ambient aerosol extinction sigma(ep)(lambda) in the lower troposphere. During one month, a heavily instrumented aircraft with well-characterized aerosol sampling ability carrying well-proven and new aerosol instrumentation devoted most of the 60 available flight hours to flying vertical profiles over the heavily instrumented ARM Southern Great Plains (SGP) Climate Research Facility (CRF). This allowed us to compare vertical extinction profiles obtained from six different instruments: airborne Sun photometer (AATS-14), airborne nephelometer/absorption photometer, airborne cavity ring-down system, ground-based Raman lidar, and two ground-based elastic backscatter lidars. We find the in situ measured sigma(ep)(lambda) to be lower than the AATS-14 derived values. Bias differences are 0.002-0.004 Km(-1) equivalent to 13-17% in the visible, or 45% in the near-infrared. On the other hand, we find that with respect to AATS-14, the lidar sigma(ep)(lambda) are higher: Bias differences are 0.004 Km(-1) (13%) and 0.007 Km(-1) (24%) for the two elastic backscatter lidars (MPLNET and MPLARM, lambda = 523 nm) and 0.029 Km(-1) (54%) for the Raman lidar (lambda = 355 nm). An unnoticed loss of sensitivity of the Raman lidar had occurred leading up to AIOP, and we expect better agreement from the recently restored system. Looking at the collective results from six field campaigns conducted since 1996, airborne in situ measurements of sigma(ep)(lambda) tend to be biased slightly low (17% at visible wavelengths) when compared to airborne Sun photometer sigma(ep)(lambda). On the other hand, sigma(ep)(lambda) values derived from lidars tend to have no or positive biases. From the bias differences we conclude that the typical systematic error associated with measuring the tropospheric vertical profile of the ambient aerosol extinction with current state-of-the-art instrumentation is 15-20% at visible wavelengths and potentially larger in the UV and near-infrared. C1 NASA, Bay Area Environm Res Inst, Ames Res Ctr, Moffett Field, CA 94035 USA. Bay Area Environm Res Inst, Sonoma, CA USA. NASA, SAIC, Langley Res Ctr, Hampton, VA 23681 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Ctr Interdisciplinary Remotely Piloted Aircraft S, Marina, CA 93633 USA. Los Gatos Res Inc, Mountain View, CA 94041 USA. NOAA, Air Resources Lab, Boulder, CO 80305 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP NASA, Bay Area Environm Res Inst, Ames Res Ctr, MS 245-5, Moffett Field, CA 94035 USA. EM bschmid@mail.arc.nasa.gov RI Smirnov, Alexander/C-2121-2009; Welton, Ellsworth/A-8362-2012; Hallar, Anna Gannet/I-9104-2012 OI Smirnov, Alexander/0000-0002-8208-1304; Hallar, Anna Gannet/0000-0001-9972-0056 NR 110 TC 51 Z9 51 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 FEB 1 PY 2006 VL 111 IS D5 AR D05S07 DI 10.1029/2005JD005837 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 010BG UT WOS:000235157800001 ER PT J AU Hirschi, M Seneviratne, SI Schar, C AF Hirschi, M Seneviratne, SI Schar, C TI Seasonal variations in terrestrial water storage for major midlatitude river basins SO JOURNAL OF HYDROMETEOROLOGY LA English DT Article ID REGIONAL CLIMATE MODEL; SOIL WETNESS PROJECT; DATA ASSIMILATION; ECMWF REANALYSIS; UNITED-STATES; VAPOR TRANSPORT; SUMMER DRYNESS; ENERGY BUDGETS; SURFACE-WATER; MOISTURE AB This paper presents a new diagnostic dataset of monthly variations in terrestrial water storage for 37 midlatitude river basins in Europe, Asia, North America, and Australia. Terrestrial water storage is the sum of all forms of water storage on land surfaces, and its seasonal and interannual variations are in principle determined by soil moisture, groundwater, snow cover, and surface water. The dataset is derived with the combined atmospheric and terrestrial water-balance approach using conventional streamflow measurements and atmospheric moisture convergence data from the ECMWF 40-yr Re-Analysis (ERA-40). A recent study for the Mississippi River basin (Seneviratne et al. 2004) has demonstrated the validity of this diagnostic approach and found that it agreed well with in situ observations in Illinois. The present study extends this previous analysis to other regions of the midlatitudes. A systematic analysis is presented of the slow drift that occurs with the water-balance approach. It is shown that the drift not only depends on the size of the catchment under consideration, but also on the geographical region and the underlying topography. The drift is in general not constant in time, but artificial inhomogeneities may result from changes in the global observing system used in the 44 yr of the reanalysis. To remove this time-dependent drift, a simple high-pass filter is applied. Validation of the results is conducted for several catchments with an appreciable coverage of in situ soil moisture and snow cover depth observations in the former Soviet Union, Mongolia, and China. Although the groundwater component is not accounted for in these observations, encouraging cot-relations are found between diagnostic and in situ estimates of terrestrial water storage, both for seasonal and interannual variations. Comparisons conducted against simulated ERA-40 terrestrial water storage variations suggest that the reanalysis substantially underestimates the amplitude of the seasonal cycle. The basin-scale water-balance (BSWB) dataset is available for download over the Internet. It constitutes a useful tool for the validation of climate models, large-scale land surface data assimilation systems, and indirect observations of terrestrial water storage variations. C1 ETH, Inst Atmospher & Climate Sci, CH-8092 Zurich, Switzerland. NASA, Goddard Space Flight Ctr, Goddard Earth Sci & Technol Ctr, Greenbelt, MD 20771 USA. RP Hirschi, M (reprint author), ETH, Inst Atmospher & Climate Sci, Univ Str 16, CH-8092 Zurich, Switzerland. EM martin.hirschi@env.ethz.ch RI Schar, Christoph/A-1033-2008; Seneviratne, Sonia/G-8761-2011 OI Schar, Christoph/0000-0002-4171-1613; Seneviratne, Sonia/0000-0001-9528-2917 NR 74 TC 47 Z9 47 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1525-755X J9 J HYDROMETEOROL JI J. Hydrometeorol. PD FEB PY 2006 VL 7 IS 1 BP 39 EP 60 DI 10.1175/JHM480.1 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 025QD UT WOS:000236281100003 ER PT J AU Fedele, F AF Fedele, F TI Extreme events in nonlinear random seas SO JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article DE extreme crest; Zakharov equation; wave-wave interaction; energy transfer; probability of exceedance; freak wave ID UNSTEADY GRAVITY WAVES; FREAK WAVES; DEEP-WATER; EXPECTED STRUCTURE; FINITE AMPLITUDE; GAUSSIAN SEA; DYNAMICS; SURFACE; MECHANICS; SPECTRUM AB In this paper, the occurrence of extreme events due to the four-wave resonance interaction. in weakly nonlinear water naves is investigated. The starting point is the Zakharov equation, which governs the dynamics of the spectral components of the surface displacement. It is proven. that the optimal spectral components giving an extreme crest are solutions of a well-defined constrained optimization problem. A new analytical expression,for the probability of exceedance of the wave crest is then proposed for the prediction of freak wave events. C1 Univ Vermont, Dept Mech Engn, Burlington, VT 05405 USA. RP NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-5,Bldg 32,Room S043-H, Greenbelt, MD 20771 USA. EM fedele@gmao.gsfc.nasa.gov RI Fedele, Francesco/J-7651-2012 OI Fedele, Francesco/0000-0001-6403-4224 NR 34 TC 7 Z9 7 U1 0 U2 2 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0892-7219 EI 1528-896X J9 J OFFSHORE MECH ARCT JI J. Offshore Mech. Arct. Eng. Trans. ASME PD FEB PY 2006 VL 128 IS 1 BP 11 EP 16 DI 10.1115/1.2151202 PG 6 WC Engineering, Ocean; Engineering, Mechanical SC Engineering GA 013BP UT WOS:000235384900002 ER EF