FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Gu, MF Beiersdorfer, P Brown, GV Kahn, SM Liedahl, DA Reed, KJ Savin, DW AF Gu, MF Beiersdorfer, P Brown, GV Kahn, SM Liedahl, DA Reed, KJ Savin, DW TI Laboratory measurements of resonant contributions to Fe XXIV line emission SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID DIELECTRONIC-RECOMBINATION; ELECTRON AB Using an electron beam ion trap, we have measured the relative cross sections for Fe XXIV line emission at electron energies between 0.7 and 3.0 keV. Good agreements with distorted wave and R-matrix calculations are found at energies above 1.5 keV. At lower energies, the contributions of resonant excitation are observed and agree with R-matrix calculations. Below the excitation thresholds, the intensities of dielectronic recombination satellites for capture into n greater than or equal to 5 levels are measured. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gu, MF (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. RI Savin, Daniel/B-9576-2012 OI Savin, Daniel/0000-0002-1111-6610 NR 7 TC 0 Z9 0 U1 2 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 310 EP 311 DI 10.1238/Physica.Topical.080a00310 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100057 ER PT J AU Savin, DW Beck, B Beiersdorfer, P Kahn, SM Brown, GV Gu, MF Liedahl, DA Scofield, JH AF Savin, DW Beck, B Beiersdorfer, P Kahn, SM Brown, GV Gu, MF Liedahl, DA Scofield, JH TI Simulations of a Maxwellian plasma using an electron beam ion trap SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID DIELECTRONIC SATELLITE SPECTRA; HELIUM-LIKE IONS; X-RAY SPECTROMETER; EXCITATION RATES; INNER-SHELL; RECOMBINATION; IRON AB Using the Lawrence-Livermore electron beam ion trap (LLNL-EBIT), we produce a quasi-Maxwellian plasma by sweeping the energy of the nearly monoenergetic beam so the time spent an any energy is proportional to the Maxwell-Boltzmann probability at that energy. To verify the accuracy of the quasi-Maxwellian, we measure line emission due to dielectronic recombination (DR) and electron impact excitation (EIE) of Mg10+ and Ne8+, for a range of simulated temperatures. The ratio of DR to EIE lines in heliumlike ions is a well understood temperature diagnostic. The spectroscopically inferred temperatures are in excellent agreement with the simulated temperatures. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Savin, DW (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. RI Savin, Daniel/B-9576-2012 OI Savin, Daniel/0000-0002-1111-6610 NR 15 TC 7 Z9 7 U1 2 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 312 EP 313 DI 10.1238/Physica.Topical.080a00312 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100058 ER PT J AU Swiat, P Warczak, A Stohlker, T Bosch, F Kozhuharov, C Mokler, PH Reich, H Dunford, RW Rymuza, P Ludziejewski, T Stachura, Z AF Swiat, P Warczak, A Stohlker, T Bosch, F Kozhuharov, C Mokler, PH Reich, H Dunford, RW Rymuza, P Ludziejewski, T Stachura, Z TI Monte Carlo simulations of atomic processes at the gas jet target of the ESR storage ring SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID BARE URANIUM IONS; ELECTRON-CAPTURE; HEAVY-IONS; COLLISIONS AB A Monte Carlo simulation program of X-ray spectra produced in collisions of fast ions with a gas-jet target of a storage ring is presented. The calculated spectra are compared with experimental data obtained at the ESR storage ring of GSI in Darmstadt. C1 Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. Gesell Schwerionenforsch GmbH, D-64220 Darmstadt, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Inst Nucl Studies, Swierk, Poland. Inst Nucl Phys, Krakow, Poland. RP Swiat, P (reprint author), Jagiellonian Univ, Inst Phys, Reymonta 4, PL-30059 Krakow, Poland. NR 13 TC 4 Z9 4 U1 0 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 326 EP 328 DI 10.1238/Physica.Topical.080a00326 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100065 ER PT J AU Stohlker, T Bosch, F Dunford, RW Kozhuharov, C Ludziejewski, T Mokler, PH Stachura, Z Swiat, P Warczak, A AF Stohlker, T Bosch, F Dunford, RW Kozhuharov, C Ludziejewski, T Mokler, PH Stachura, Z Swiat, P Warczak, A TI State selective electron capture studies: The contribution of M1-and E2-transitions to the Lyman radiation of H-like uranium SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID RELATIVISTIC ATOMIC-COLLISIONS; CROSS-SECTIONS; IONS AB The heavy-ion storage ring ESR provides a unique possibility to decelerate highly charged ions up to bare uranium to energies which are far below the energy required for the efficient production of high charge states. This technique allows for a detailed study of atomic collision dynamics and, in particular, for an (n,l,j)-sensitive investigation of electron capture processes by means of Xray spectroscopy. The results of a first state selective capture investigation performed for decelerated bare uranium ion are discussed and their relevance for Lamb shift investigations on high-Z hydrogenlike ions is emphasized. C1 Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. GSI Darmstadt, D-62491 Darmstadt, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Inst Nucl Phys, Krakow, Poland. Jagiellonian Univ, Krakow, Poland. RP Stohlker, T (reprint author), Univ Frankfurt, Inst Kernphys, August Euler Str 2, D-60486 Frankfurt, Germany. NR 8 TC 9 Z9 9 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 379 EP 380 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100085 ER PT J AU Abdallah, MA Wolff, W Wolf, HE Kamber, E Cocke, CL Stockli, M AF Abdallah, MA Wolff, W Wolf, HE Kamber, E Cocke, CL Stockli, M TI Formation of dynamic quasi-molecules in ionizing collisions at low to intermediate velocities SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID ION MOMENTUM SPECTROSCOPY; HIGHLY-CHARGED IONS; CONTINUUM ELECTRONS; ATOM COLLISIONS; LOW-ENERGY; HE; SINGLE; SLOW AB The technique of cold-target recoil-ion momentum spectroscopy is used to study the process of ionization in slow to intermediate-velocity collisions. Some evidence for the role of the quasi-molecular promotion in the ionization process is presented. The two collision systems He+ - He and Ne+ - Ne are chosen for illustration. C1 Kansas State Univ, JR Macdonald Lab, Dept Phys, Manhattan, KS 66506 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Fed Rio de Janeiro, Inst Fis, Rio De Janeiro, Brazil. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49038 USA. RP Abdallah, MA (reprint author), Kansas State Univ, JR Macdonald Lab, Dept Phys, Manhattan, KS 66506 USA. RI Wolff, Wania/O-5556-2015 NR 13 TC 1 Z9 1 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 405 EP 407 DI 10.1238/Physica.Topical.080a00405 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100096 ER PT J AU Kramer, A Stohlker, T Fritzsche, S Bosch, F Ionescu, DC Kozhuharov, C Ludziejewski, T Mokler, PH Rymuza, P Stachura, Z Swiat, P Warczak, A AF Kramer, A Stohlker, T Fritzsche, S Bosch, F Ionescu, DC Kozhuharov, C Ludziejewski, T Mokler, PH Rymuza, P Stachura, Z Swiat, P Warczak, A TI Projectile excitation studies for high-Z ions at a storage ring SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID K-SHELL EXCITATION; H-LIKE; COLLISIONS AB The formation of excited states via Coulomb excitation in relativistic ion-atom collisions can be studied for high-Z ions by the observation of the radiative decay of the excited levels to the ground state, This has been demonstrated in a first study, recently performed for H- and He-like Pi ions [1]. However, in that study solid targets were used and the results suffered from low counting statistics. Here, we report an extension of these investigations performed at the gas-jet target of the ESR storage ring where the K-shell excitation has been measured for H-like Au ions in collisions with gaseous Ar atoms. C1 Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Gesell Schwerionenforsch, D-64291 Darmstadt, Germany. Univ Kassel, D-34132 Kassel, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Soltan Inst Nucl Studies, PL-05400 Swierk, Poland. Inst Nucl Phys, PL-31342 Krakow, Poland. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. RP Kramer, A (reprint author), Univ Frankfurt, Inst Kernphys, August Euler Str 6, D-60486 Frankfurt, Germany. NR 4 TC 3 Z9 3 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 424 EP 425 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100104 ER PT J AU Ludziejewski, T Stohlker, T Beyer, H Bosch, F Fritzsche, S Ionescu, DC Kozhuharov, C Kramer, A Liesen, D Mokler, PH Rymuza, P Stachura, Z Swiat, P Warczak, A AF Ludziejewski, T Stohlker, T Beyer, H Bosch, F Fritzsche, S Ionescu, DC Kozhuharov, C Kramer, A Liesen, D Mokler, PH Rymuza, P Stachura, Z Swiat, P Warczak, A TI Two-electron processes in relativistic collisions of He-like uranium with gaseous targets SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID IONS AB The simultaneous excitation-ionization and excitation-capture processes in collisions of 223 MeV/u He-like uranium ions with heavy target atoms are identified by measuring the X-ray (L-->K) transitions in coincidence with projectiles undergoing charge exchange. The state selective cross sections for the population of the L-shell sub-levels of the projectile are determined, and in the case of excitation-ionization data compared to the detailed relativistic calculations. It is emphasized that the experimental data can serve as an important benchmark of the independent particle approximation and fully relativistic perturbative models, for the domain of relativistic ion-atom collisions. C1 Gesellschaft Schwerionenforsch, D-64291 Darmstadt, Germany. Univ Frankfurt, D-60486 Frankfurt, Germany. Univ Kassel, D-34132 Kassel, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Soltan Institute Nucl Studies, PL-05400 Otwock, Poland. Inst Nucl Phys, PL-31342 Krakow, Poland. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. RP Ludziejewski, T (reprint author), Gesellschaft Schwerionenforsch, D-64291 Darmstadt, Germany. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 426 EP 428 DI 10.1238/Physica.Topical.080a00426 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100105 ER PT J AU Lopez-Urrutia, JRC Beiersdorfer, P Widmann, K Decaux, V AF Lopez-Urrutia, JRC Beiersdorfer, P Widmann, K Decaux, V TI Visible spectrum of highly charged ions: the forbidden optical lines of Kr, Xe, and Ba ions in the ArI to NiI isoelectronic sequence SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID TRANSITIONS AB We present experimental data on visible lines produced by Kr (q = 11+ to 22+), Xe (q = 18+ to 35+), and Pa (q = 28+ to 36+) ions, corresponding mainly to 3s(l) 3p(m) 3d(n) configurations, obtained with the LLNL electron beam ion traps. Tentative assignments for the lines are made. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Lopez-Urrutia, JRC (reprint author), Univ Freiburg, Dept Phys, D-79104 Freiburg, Germany. RI Crespo Lopez-Urrutia, Jose R./F-7069-2011 OI Crespo Lopez-Urrutia, Jose R./0000-0002-2937-8037 NR 11 TC 21 Z9 21 U1 1 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 448 EP 449 PG 2 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100114 ER PT J AU Trabert, E Beiersdorfer, P Utter, SB AF Trabert, E Beiersdorfer, P Utter, SB TI The EBIT quest for better transition probabilities of forbidden lines SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID BEAM ION-TRAP; RADIATIVE LIFETIME AB Electron beam ion traps (EBIT) lifetime measurements on forbidden lines in the visible spectrum have reached a precision of only about 5%, whereas some EBIT lifetimes measured on X-ray transitions are good to 0.5% already. Scientific and technical problems encountered when trying to improve on these limits are discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94551 USA. RP Trabert, E (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94551 USA. NR 13 TC 10 Z9 10 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 450 EP 452 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100115 ER PT J AU Jasper, E Vasilyev, A Kukla, K Vogt, CV Livingston, AE Berry, HG Cheng, S Curtis, LJ Dunford, RW AF Jasper, E Vasilyev, A Kukla, K Vogt, CV Livingston, AE Berry, HG Cheng, S Curtis, LJ Dunford, RW TI Lifetime measurements for allowed and forbidden transitions SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID 3P P-2(3/2) LEVEL; INTERCOMBINATION TRANSITIONS; ISOELECTRONIC SEQUENCE; LINE STRENGTHS; IONS AB Excited state lifetimes ranging in value from picoseconds to nanoseconds are reported for selected highly charged ions. The measurements utilize beam-foil excitation and photon-counting extreme ultraviolet spectroscopy with position sensitive detection. Lifetimes are reported for both allowed and forbidden transitions in several classes of highly charged ions. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Toledo, Dept Phys & Astron, Toledo, OH 43606 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Livingston, AE (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 13 TC 4 Z9 4 U1 0 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 466 EP 468 DI 10.1238/Physica.Topical.080a00466 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100121 ER PT J AU Schaffer, HW Mokler, PH Dunford, RW Kozhuharov, C Kramer, A Ludziejewski, T Prinz, HT Rymuza, P Sarkadi, L Stohlker, T Swiat, P Warczak, A AF Schaffer, HW Mokler, PH Dunford, RW Kozhuharov, C Kramer, A Ludziejewski, T Prinz, HT Rymuza, P Sarkadi, L Stohlker, T Swiat, P Warczak, A TI Measurement of the spectral distribution for the two-photon decay of the 1s2s S-1(0) level in heliumlike gold SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID 2-PHOTON DECAY; EXCITATION; STATE; IONS AB A first measurement of the spectral distribution of the two-photon decay of the 1s2s S-1(0) level in heliumlike gold is reported. This study extends our earlier work for heliumlike krypton and nickel to higher atomic numbers Z into the fully relativistic regime. The measured spectral shape of the two-photon decay differs from that observed at intermediate Z but is in agreement with the results of a recent fully relativistic calculation of Derevianko and Johnson. C1 Gesellschaft Schwerionenforsch MbH, D-64291 Darmstadt, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Soltan Inst Nucl Studies, PL-05400 Otwock, Poland. Inst Nucl Res, H-4001 Debrecen, Hungary. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. RP Schaffer, HW (reprint author), Gesellschaft Schwerionenforsch MbH, D-64291 Darmstadt, Germany. NR 9 TC 2 Z9 2 U1 0 U2 1 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 469 EP 471 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100122 ER PT J AU Faenov, AY Magunov, AI Pikuz, TA Skobelev, IY Pikuz, SA Urnov, AM Abdallah, J Clark, REH Cohen, J Jonson, RP Kyrala, GA Wilke, MD Maksimchuk, A Umstadter, D Nantel, N Doron, R Behar, E Mandelbaum, P Schwob, JJ Dubau, J Rosmej, FB Osterheld, A AF Faenov, AY Magunov, AI Pikuz, TA Skobelev, IY Pikuz, SA Urnov, AM Abdallah, J Clark, REH Cohen, J Jonson, RP Kyrala, GA Wilke, MD Maksimchuk, A Umstadter, D Nantel, N Doron, R Behar, E Mandelbaum, P Schwob, JJ Dubau, J Rosmej, FB Osterheld, A TI High-resolved X-ray spectra of hollow atoms in a femtosecond laser-produced solid plasma SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT IX International Conference on Physics of Highly Charged Ions CY SEP 09-14, 1998 CL BENSHEIM, GERMANY ID SATELLITE TRANSITIONS; SPECTROSCOPY; EXCITATION; RADIATION; SURFACE; IONS AB A new type of quasi-continuous spectra of femtosecond laser plasma in the vicinity of multicharged H-like and He-like ion resonance lines were observed and interpreted for the first time. It is shown that such spectra were generated by multicharged hollow ions and are caused by super high density conditions provided by a high contrast laser pulse. C1 VNIIFTRI, Multicharged Ions Spectra Data Ctr, Mendeleevo 141570, Moscow Region, Russia. RAS, PN Lebedev Phys Inst, Moscow 118927, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Ctr Ultrafast Opt Sci, Ann Arbor, MI 48109 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Observ Paris, F-9211195 Meudon, France. Tech Univ Darmstadt, Inst Nucl Phys, Dept Radiat & Nucl Phys, D-64289 Darmstadt, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Faenov, AY (reprint author), VNIIFTRI, Multicharged Ions Spectra Data Ctr, Mendeleevo 141570, Moscow Region, Russia. RI Doron, Ramy/I-2064-2013; Umstadter, Donald/A-1581-2016; Pikuz, Sergey/M-8231-2015 OI Umstadter, Donald/0000-0002-2182-4346; NR 18 TC 37 Z9 37 U1 2 U2 3 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PY 1999 VL T80B BP 536 EP 538 DI 10.1238/Physica.Topical.080a00536 PG 3 WC Physics, Multidisciplinary SC Physics GA 227RH UT WOS:000082093100149 ER PT J AU Choi, IH Yu, PY AF Choi, IH Yu, PY TI Pressure dependence of band gaps in the quaternary semiconductors Cu(In,Ga)Se-2 SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 8th International Conference on High Pressure Semiconductor Physics (HPSP-VIII) CY AUG 09-13, 1998 CL THESSALONIKI, GREECE ID AGGASE2 AB We report the photoluminescence and absorption spectra of a series of quaternary chalcopyrite alloys with the formula: CuIn1-xGaxSe2 where x varies between 0 and 1 in steps of 0.25. Using a diamond anvil cell we have studied their band gaps and impurity emission peak energies as a function of pressure. We found that while the band gap of CuIn1-xGaxSe2 varies nonlinearly with x the pressure coefficient (alpha) varies linearly with x at a rather large rate of d alpha/dx = 18.6 meV/GPa. We interpret our results in terms of recent theoretical calculations which have been proposed to explain the large difference in alpha between CuGaSe2 and CuInSe2. C1 Chung Ang Univ, Dept Phys, Seoul 156756, South Korea. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Choi, IH (reprint author), Chung Ang Univ, Dept Phys, Seoul 156756, South Korea. NR 10 TC 12 Z9 13 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JAN PY 1999 VL 211 IS 1 BP 51 EP 55 DI 10.1002/(SICI)1521-3951(199901)211:1<51::AID-PSSB51>3.3.CO;2-L PG 5 WC Physics, Condensed Matter SC Physics GA 159QK UT WOS:000078185000011 ER PT J AU Iota, V Weinstein, BA AF Iota, V Weinstein, BA TI Pitfalls of using pressure to assign the luminescence of large-lattice-relaxation defects SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 8th International Conference on High Pressure Semiconductor Physics (HPSP-VIII) CY AUG 09-13, 1998 CL THESSALONIKI, GREECE ID II-VI SEMICONDUCTORS; ELECTRONIC-STRUCTURE; HYDROSTATIC-PRESSURE; MAGNETIC-RESONANCE; ZINC VACANCY; ZNSE; DEEP; IMPURITIES; PHOSPHORUS; CENTERS AB Deep defects are often assumed to be insensitive to applied pressure because of their localized character. However, in recent photoluminescence (PL) experiments, several deep acceptor bands in ZnSe were found to shift with pressure substantially faster than the ZnSe bandgap. This shows that the optical (viz., PL) levels of these accepters become more shallow under compression, a result that, if also true for the thermal defect levels, is important for p-type doping problems in II-VI semiconductors. We report investigations of the C-3v-relaxed isolated Zn-vacancy (V-Zn) in ZnSe that help to resolve these issues. High-pressure PL and PL-excitation (PLE) experiments and calculations are performed on this system. We find that the V-Zn-related PL and PLE bands have pressure coefficients that are, respectively, larger and smaller than that of the ZnSe bandgap. Hence, the Stokes-shift decreases with pressure. These results can not be understood without taking explicit account of lattice relaxation. We employ a defect-molecule model with atomic wavefunctions to calculate semi-empirical configuration-coordinate diagrams for the V-Zn defect as a function of pressure. We find that compression increases the Jahn-Teller coupling, but not sufficiently to overcome lattice stiffening. Overall, the V-Zn thermal level deepens, inhibiting p-type doping. C1 SUNY Buffalo, Dept Phys, Amherst, NY 14260 USA. RP Iota, V (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 31 TC 6 Z9 6 U1 1 U2 4 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JAN PY 1999 VL 211 IS 1 BP 91 EP 104 DI 10.1002/(SICI)1521-3951(199901)211:1<91::AID-PSSB91>3.0.CO;2-M PG 14 WC Physics, Condensed Matter SC Physics GA 159QK UT WOS:000078185000018 ER PT J AU Choi, IH Yu, PY AF Choi, IH Yu, PY TI Pressure dependence of band gaps and deep centers in chalcopyrite semiconductors SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 8th International Conference on High Pressure Semiconductor Physics (HPSP-VIII) CY AUG 09-13, 1998 CL THESSALONIKI, GREECE ID AGGASE2; DEFECTS AB We present a review of the effect of high pressure on the electronic, optical and defect properties in chalcopyrite semiconductors with the formula I-III-VI2. We show that the linear pressure coefficients of the band gap in these materials are not constant. While the bulk moduli of this family of semiconductors are rather constant, the dependence of the band gap on volume exhibits systematic trends when the group III cations are varied. We also found that there are deep center emissions whose pressure coefficients are larger than those of the band gap. We propose that the origin of these deep emissions are deep accepters and their pressure coefficients can be understood in terms of p-d hybridization in the valence bands. C1 Chung Ang Univ, Dept Phys, Seoul 156756, South Korea. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Choi, IH (reprint author), Chung Ang Univ, Dept Phys, Seoul 156756, South Korea. EM PYYU@LBL.GOV NR 22 TC 13 Z9 13 U1 1 U2 2 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JAN PY 1999 VL 211 IS 1 BP 143 EP 155 DI 10.1002/(SICI)1521-3951(199901)211:1<143::AID-PSSB143>3.3.CO;2-2 PG 13 WC Physics, Condensed Matter SC Physics GA 159QK UT WOS:000078185000025 ER PT J AU Zeman, J Martinez, G Yu, PY Kwok, SH Uchida, K AF Zeman, J Martinez, G Yu, PY Kwok, SH Uchida, K TI GaAs/(ordered)GaInP2 heterostructures under pressure and high magnetic fields SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 8th International Conference on High Pressure Semiconductor Physics (HPSP-VIII) CY AUG 09-13, 1998 CL THESSALONIKI, GREECE ID UP-CONVERSION; BAND; GAINP; PHOTOLUMINESCENCE AB The results of extended studies of photoluminescence (PL) and up-converted PL (UPL) of partially ordered GaInP2 alloy layers under hydrostatic pressure and high magnetic field are presented. It appears that the efficient UPL is observed when the GaAs/GaInP2 interface has a type II alignment. This condition can be reached also by hydrostatic pressure. Dramatic changes of the character of PL spectra measured on less ordered samples are explained by pressure and/or magnetic field induced localization of electrons in small domains in GaInP2 nearby the interface. C1 MPI FKF, Grenoble High Magnet Field Lab, F-38042 Grenoble 9, France. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Electrocommun, Dept Commun & Syst, Tokyo, Japan. RP Zeman, J (reprint author), MPI FKF, Grenoble High Magnet Field Lab, 25 Av Martyrs, F-38042 Grenoble 9, France. NR 11 TC 4 Z9 4 U1 1 U2 3 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JAN PY 1999 VL 211 IS 1 BP 239 EP 246 DI 10.1002/(SICI)1521-3951(199901)211:1<239::AID-PSSB239>3.0.CO;2-O PG 8 WC Physics, Condensed Matter SC Physics GA 159QK UT WOS:000078185000038 ER PT J AU Rozenberg, GK Machavariani, GY Pasternak, MP Milner, AP Hearne, GR Taylor, RD Adler, P AF Rozenberg, GK Machavariani, GY Pasternak, MP Milner, AP Hearne, GR Taylor, RD Adler, P TI Pressure-induced metallization of the perovskite Sr3Fe2O7 SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 8th International Conference on High Pressure Semiconductor Physics (HPSP-VIII) CY AUG 09-13, 1998 CL THESSALONIKI, GREECE ID TRANSITION-METAL COMPOUNDS; DIAMOND-ANVIL CELL; ELECTRONIC-STRUCTURE AB Electrical, magnetic and structural properties of the antiferromagnetic semiconductor Sr3Fe2O7 (Fe4+, d(4)) were probed by resistance, Mossbauer spectroscopy (MS) and X-ray diffraction (XRD) measurements up to P approximate to 40 GPa using diamond-anvil cells. A sluggish pressure-induced insulator-metal (IM) transition is observed with a clear incipient metallic state at P greater than or equal to 20 GPa. The Fe(IV) 3d magnetic moments remain unaltered across the transition as deduced from MS, and XRD studies show no structural symmetry change up to 40 GPa. The results are consistent with carrier delocalization due to p-p gap closure, e.g., ligand-to-ligand charge transfer that does not involve the d-states and structural symmetry changes. A mechanism to account for the IM transition in the strontium ferrates is discussed. C1 Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Univ Witwatersrand, Dept Phys, ZA-2050 Johannesburg, South Africa. Univ Calif Los Alamos Natl Lab, MST10, Los Alamos, NM 87545 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. RP Rozenberg, GK (reprint author), Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. NR 16 TC 5 Z9 5 U1 1 U2 15 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JAN PY 1999 VL 211 IS 1 BP 351 EP 357 DI 10.1002/(SICI)1521-3951(199901)211:1<351::AID-PSSB351>3.0.CO;2-7 PG 7 WC Physics, Condensed Matter SC Physics GA 159QK UT WOS:000078185000053 ER PT J AU Harding, LB Stark, H Troe, J Ushakov, VG AF Harding, LB Stark, H Troe, J Ushakov, VG TI New studies of the unimolecular reaction NO2 reversible arrow O+NO. Part 2. Relation between high pressure rate constants and potential parameters SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID JET-COOLED NO2; VISIBLE EXCITATION SPECTRUM; PRODUCT STATE DISTRIBUTIONS; ADIABATIC CHANNEL MODEL; ION-DIPOLE CAPTURE; VIBRATIONAL-RELAXATION; OVERLAPPING RESONANCES; TRANSITION-STATE; ENERGY SURFACES; ATOMIC OXYGEN AB The potential energy surfaces of the X 1(2)A'- and C1(2)A "-states of the dissociation/recombination system NO(2)reversible arrow O + NO have been characterized by ab initio methods. Thermal rate constants for the high pressure limit of this reaction have been determined by calculating classical trajectories with simplified representations of the two ab initio potentials. The results well agree with the less accurate experimental data in this temperature range. The treatment is compared with relationships for model valence potentials which were derived earlier. It is demonstrated which parts of the potential are most relevant and to what extent the rate constants could have been predicted without specific ab initio information. C1 Univ Gottingen, Inst Phys Chem, D-37077 Gottingen, Germany. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Russian Acad Sci, Inst Chem Phys, Chernogolovka 142432, Russia. RP Univ Gottingen, Inst Phys Chem, Tammannstr 6, D-37077 Gottingen, Germany. RI Stark, Harald/E-7433-2010 NR 65 TC 37 Z9 37 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 EI 1463-9084 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PD JAN 1 PY 1999 VL 1 IS 1 BP 63 EP 72 DI 10.1039/a806521g PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 179VL UT WOS:000079350200008 ER PT J AU Gilbert, EP AF Gilbert, EP TI Incommensurate modulation in phase separating binary paraffin mixtures SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID MICROPHASE SEPARATION; SOLID-SOLUTIONS; ALKANES AB Small-angle neutron and X-ray scattering (SANS and SAXS) has been measured on C-28-C-36 mixtures quenched from the melt for compositions varying from 15.6:1 to 1:5. Satellite peaks are observed in the SAXS whose offset in Q (where Q is the scattering vector), relative to Bragg diffraction peaks associated with the average lamellar structure, are composition dependent. The offset is close to the position of the most intense peak observed in the SANS. A model for the phase separated structure is suggested based on correlated positional and substitutional disorder. C1 Australian Natl Univ, Res Sch Chem, Canberra, ACT 0200, Australia. RP Gilbert, EP (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gilbert, Elliot/A-5566-2010 OI Gilbert, Elliot/0000-0001-6413-7813 NR 22 TC 12 Z9 12 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI PCCP Phys. Chem. Chem. Phys. PY 1999 VL 1 IS 22 BP 5209 EP 5214 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 254PZ UT WOS:000083622500019 ER PT J AU Jarvis, GK Weitzel, KM Malow, M Baer, T Song, Y Ng, CY AF Jarvis, GK Weitzel, KM Malow, M Baer, T Song, Y Ng, CY TI High-resolution pulsed field ionization photoelectron-photoion coincidence study of C2H2: Accurate 0 K dissociation threshold for C2H+ SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID ENERGY; ION; SPECTROSCOPY; STATE AB By employing the newly developed pulsed field ionization photoelectron-photoion coincidence (PFI-PEPICO) apparatus of the Chemical Dynamics Beamline at the Advanced Light Source, we have examined the formation of ethynyl ion (C2H+) from acetylene at high resolution. The PFI-PEPICO (C2H2) time-of-flight spectra reveal that fragmentation of in C2H2 high-n Rydberg states occurs at energies above the dissociation threshold prior to pulsed field ionization. This study shows that for a prompt dissociation process, the disappearance energy of the parent molecule determined in PFI-PEPICO measurements provides an unambiguous measure of the 0 K ion dissociation threshold. For the formation of from this is found C2H+ C2H2 to be 17.3576 +/- 0.0010 eV. C1 Iowa State Univ, US Dept Energy, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Free Univ Berlin, Inst Phys & Theoret Chem, D-14195 Berlin, Germany. Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. RP Jarvis, GK (reprint author), Iowa State Univ, US Dept Energy, Ames Lab, Ames, IA 50011 USA. NR 30 TC 37 Z9 37 U1 1 U2 9 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI PCCP Phys. Chem. Chem. Phys. PY 1999 VL 1 IS 22 BP 5259 EP 5262 DI 10.1039/a907383c PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 254PZ UT WOS:000083622500026 ER PT J AU Schaffer, HW Dunford, RW Kanter, EP Cheng, S Curtis, LJ Livingston, AE Mokler, PH AF Schaffer, HW Dunford, RW Kanter, EP Cheng, S Curtis, LJ Livingston, AE Mokler, PH TI Measurement of the two-photon spectral distribution from decay of the 1s2s S-1(0) level in heliumlike nickel SO PHYSICAL REVIEW A LA English DT Article ID ONE-ELECTRON ATOMS; FORBIDDEN TRANSITIONS; 2-PHOTON DECAY; RATES; IONS; HYDROGENLIKE; STATES AB A measurement of the shape of the spectral distribution of two-photon decay of the 1s2s S-1(0) level in heliumlike nickel is described. Uncertainties in detector efficiencies which had limited the precision of earlier measurements were eliminated by comparing the continuum emission from two-photon decays of H-like and He-like nickel. Our results are in agreement with the nonrelativistic calculation of Drake and the fully relativistic calculation of Derevianko and Johnson and suggest a method for testing relativistic atomic many-body theory in strong fields. [S1050-2947(99)05501-8]. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Gesell Schwerionenforsch GmbH, D-64291 Darmstadt, Germany. Univ Toledo, Dept Phys & Astron, Toledo, OH 43606 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Dunford, RW (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 29 TC 19 Z9 19 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 JAN PY 1999 VL 59 IS 1 BP 245 EP 250 DI 10.1103/PhysRevA.59.245 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500038 ER PT J AU Sapirstein, J Cheng, KT Chen, MH AF Sapirstein, J Cheng, KT Chen, MH TI Potential independence of the solution to the relativistic many-body problem and the role of negative-energy states in heliumlike ions SO PHYSICAL REVIEW A LA English DT Article ID PERTURBATION-THEORY; GROUND-STATE; ELECTRON; ATOMS AB Solving the relativistic many-body problem using either many-body perturbation theory or configuration-interaction techniques is shown to lead to energies that depend slightly on the: starting potential if the effects of virtual electron-positron pairs are excluded. If they are included without a-correct-implementation of:quantum electrodynamics (QED), while this dependence is eliminated in a mathematical sense, the procedure is shown to give unphysical answers. When instead the effects of virtual electron-positron pairs are included using the S-matrix theory implementation of QED, the potential dependence is shown to be eliminated ina physical way through the inclusion of a particular class of Feynman diagrams. [S1050-2947(99)07401-6]. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sapirstein, J (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 18 TC 30 Z9 30 U1 0 U2 0 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 JAN PY 1999 VL 59 IS 1 BP 259 EP 266 DI 10.1103/PhysRevA.59.259 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500040 ER PT J AU Fontes, CJ Zhang, HL Sampson, DH AF Fontes, CJ Zhang, HL Sampson, DH TI Inclusion of the generalized Breit interaction in electron-impact excitation of ions to specific magnetic sublevels SO PHYSICAL REVIEW A LA English DT Article ID HIGHLY CHARGED IONS; CROSS-SECTIONS; POLARIZATION; LINES AB A relativistic distorted wave method for calculating cross sections for excitation of ions to specific magnetic sublevels by impact with an electron beam is expanded to include the generalized Breit interaction between the bound and free electrons. illustrative numerical results are given for heliumlike iron and xenon. The effect of inclusion of the generalized Breit interaction is very large for xenon and is even non-negligible for iron. [S1050-2947(98)08012-3]. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. RP Fontes, CJ (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, POB 1663, Los Alamos, NM 87545 USA. NR 13 TC 25 Z9 25 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 JAN PY 1999 VL 59 IS 1 BP 295 EP 299 DI 10.1103/PhysRevA.59.295 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500045 ER PT J AU Wells, JC Segev, B Eichler, J AF Wells, JC Segev, B Eichler, J TI Asymptotic channels and gauge transformations of the time-dependent Dirac equation for extremely relativistic heavy-ion collisions SO PHYSICAL REVIEW A LA English DT Article ID POSITRON PAIR PRODUCTION; IMPACT-PARAMETER DEPENDENCE; STRONG EXTERNAL FIELDS; COULOMB COLLISIONS; ELECTRON-CAPTURE; SULFUR IONS; ELECTROMAGNETIC-FIELDS; ATOMIC-COLLISIONS; CHARGE-TRANSFER; FIXED TARGETS AB We discuss the two-center, time-dependent Dirac equation describing the dynamics of an electron during a peripheral, relativistic heavy-ion collision at extreme energies. We derive a factored form, which is exact in the high-energy limit, for the asymptotic channel solutions of the Dirac equation, and elucidate their close connection with gauge transformations which transform the dynamics into a representation in which the interaction between the electron and a distant ion is of short range. We describe the implications of this relationship for solving the time-dependent Dirac equation for extremely relativistic collisions. [S1050-2947(99)03801-9]. C1 Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, Bereich Theoret Phys, D-14109 Berlin, Germany. Free Univ Berlin, Fachbereich Phys, D-14195 Berlin, Germany. RP Wells, JC (reprint author), Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. RI Wells, Jack/D-3675-2016 OI Wells, Jack/0000-0002-5083-3030 NR 45 TC 6 Z9 6 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 JAN PY 1999 VL 59 IS 1 BP 346 EP 357 DI 10.1103/PhysRevA.59.346 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500052 ER PT J AU Spielberger, L Brauning, H Muthig, A Tang, JZ Wang, J Qiu, Y Dorner, R Jagutzki, O Tschentscher, T Honkimaki, V Mergel, V Achler, M Weber, T Khayyat, K Burgdorfer, J McGuire, J Schmidt-Bocking, H AF Spielberger, L Brauning, H Muthig, A Tang, JZ Wang, J Qiu, Y Dorner, R Jagutzki, O Tschentscher, T Honkimaki, V Mergel, V Achler, M Weber, T Khayyat, K Burgdorfer, J McGuire, J Schmidt-Bocking, H TI Cross-section ratio of double to single ionization of helium by Compton scattering of 40-100-keV x rays SO PHYSICAL REVIEW A LA English DT Article ID HIGH-ENERGY PHOTONS; DOUBLE-ELECTRON IONIZATION; CHARGED-PARTICLES; EXCITATION-IONIZATION; HE; ATOMS AB We have measured the ratio of cross sections for double to single ionization of helium by Compton scattering, R-C = sigma(C)(++)/sigma(C)(+), at photon energies of 40, 80, and 100 keV using cold target recoil-ion momentum spectroscopy. Comparison with calculations involving highly correlated initial states and approximate final states with and without final-state correlations, represented by 3C and 2C wave functions respectively, shows that the influence of final-state correlations persists to very high photon energies. A comparison with recent charged-particle data is made. [S1050-2947(99)04701-0]. C1 Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Vienna Tech Univ, Inst Theoret Phys, A-1040 Vienna, Austria. RP Spielberger, L (reprint author), Univ Frankfurt, Inst Kernphys, August Euler Str 6, D-60486 Frankfurt, Germany. EM spielberger@ikf.uni-frankfurt.de RI Doerner, Reinhard/A-5340-2008; Weber, Thorsten/K-2586-2013 OI Doerner, Reinhard/0000-0002-3728-4268; Weber, Thorsten/0000-0003-3756-2704 NR 35 TC 24 Z9 24 U1 1 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 JAN PY 1999 VL 59 IS 1 BP 371 EP 379 DI 10.1103/PhysRevA.59.371 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500055 ER PT J AU Savchenko, VI Fisch, NJ Panteleev, AA Starostin, AN AF Savchenko, VI Fisch, NJ Panteleev, AA Starostin, AN TI Role of quantum interference in thermodynamic equilibrium SO PHYSICAL REVIEW A LA English DT Article ID SPONTANEOUS EMISSION CANCELLATION; 3-LEVEL SYSTEM; DRIVEN; INVERSION; ATOM AB The influence of quantum interference between different decay channels of three-level atoms on various characteristics of matter and radiation is considered for the case of thermodynamic equilibrium of atoms in a photon gas. It is shown that for rare gases when collisions between atoms are not important, the direct consequence of such an interference is a spontaneously induced atomic coherence between two upper levels. Therefore, for an accurate description of such atoms and radiation in thermodynamic equilibrium with each other it is not sufficient to specify only Boltzmann exponents, which correspond to the diagonal elements of the density matrix. The reason for this is that the conventional Boltzmann description is applied to infinitely sharp eigenstates of the unperturbed Hamiltonian. As we show, it becomes essential to take into account nonzero width of the;levels if the levels are relatively close to each other. This produces nonzero nondiagonal elements of the density matrix that modify the emissivity of the equilibrium medium and lead to a zero point at a certain frequency as well as to an enhanced intensity in the red wing at the corresponding temperature. It is shown that the occupation number of the photons is not changed and obeys the equilibrium Planck distribution. [S1050-2947(98)06911-X]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Savchenko, VI (reprint author), Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. NR 15 TC 5 Z9 5 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 JAN PY 1999 VL 59 IS 1 BP 708 EP 713 DI 10.1103/PhysRevA.59.708 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500089 ER PT J AU Price, DL Pasquarello, A AF Price, DL Pasquarello, A TI Number of independent partial structure factors for a disordered n-component system SO PHYSICAL REVIEW B LA English DT Article ID DIFFRACTION; SPECKLE; SPECTRUM; SIO2 AB n(n + 1)/2 independent diffraction measurements are needed to obtain complete partial structure information for a disordered n-component condensed system. A previous assertion that only n of these are independent is shown to be inapplicable, for different reasons, to both the three-dimensional partial structure factors S-ab(Q) and the orientational averages S-ab(Q). The fluctuations of S-ab(Q) about S-ab(Q) and the effects of thermal motion are discussed. [S0163-1829(99)00491-4]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. IN Ecublens, Inst Romand Rech Numer Phys Mat, CH-1015 Lausanne, Switzerland. RP Price, DL (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Pasquarello, Alfredo/G-2883-2011; Price, David Long/A-8468-2013 NR 16 TC 11 Z9 12 U1 0 U2 2 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 JAN 1 PY 1999 VL 59 IS 1 BP 5 EP 7 DI 10.1103/PhysRevB.59.5 PG 3 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800002 ER PT J AU Rasmussen, KO Zharnitsky, V Mitkov, I Gronbech-Jensen, N AF Rasmussen, KO Zharnitsky, V Mitkov, I Gronbech-Jensen, N TI Higher-order effects on Shapiro steps in Josephson junctions SO PHYSICAL REVIEW B LA English DT Article ID INVERTED PENDULUM; STABILITY; NOISE; CHAOS AB We demonstrate that the well known phase-locking mechanism leading to Shapiro steps in ac-driven Josephson junctions is always accompanied by a higher-order phase-locking mechanism similar to that of the parametrically driven pendulum. This effect, resulting in a pi-periodic effective potential for the phase, manifests itself clearly in the parameter regions when the usual Shapiro steps are expected to vanish. [S0163-1829(99)02502-3]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Rasmussen, KO (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Rasmussen, Kim/B-5464-2009 OI Rasmussen, Kim/0000-0002-4029-4723 NR 18 TC 6 Z9 6 U1 0 U2 0 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 JAN 1 PY 1999 VL 59 IS 1 BP 58 EP 61 DI 10.1103/PhysRevB.59.58 PG 4 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800016 ER PT J AU Kern, S Robinson, RA Nakotte, H Lander, GH Cort, B Watson, P Vigil, FA AF Kern, S Robinson, RA Nakotte, H Lander, GH Cort, B Watson, P Vigil, FA TI Crystal-field transition in PuO2 SO PHYSICAL REVIEW B LA English DT Article ID ACTINIDE DIOXIDES; UO2; SPECTROSCOPY; STATE AB A single peak at 123 meV has been found in the neutron inelastic-scattering spectrum of PuO2 measured on the PHAROS chopper spectrometer at LANSCE. This is ascribed to the Gamma(1) to Gamma(4) transition of the ground-state crystal-field multiplet and quantitative agreement is obtained between the observed and calculated cross section. The peak is broadened beyond the instrumental resolution. A short discussion is presented on how this observation complements our understanding of the actinide oxides. [S0163-1829(99)02602-8]. C1 Colorado State Univ, Dept Phys, Ft Collins, CO 80524 USA. Univ Calif Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. Commiss European Communities, Joint Res Ctr, Inst Transuranium Elements, D-76125 Karlsruhe, Germany. RP Kern, S (reprint author), Colorado State Univ, Dept Phys, Ft Collins, CO 80524 USA. NR 23 TC 45 Z9 45 U1 2 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 JAN 1 PY 1999 VL 59 IS 1 BP 104 EP 106 DI 10.1103/PhysRevB.59.104 PG 3 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800028 ER PT J AU Gordon, JE Fisher, RA Jia, YX Phillips, NE Reklis, SF Wright, DA Zettl, A AF Gordon, JE Fisher, RA Jia, YX Phillips, NE Reklis, SF Wright, DA Zettl, A TI Specific heat of Nd0.67Sr0.33MnO3 SO PHYSICAL REVIEW B LA English DT Article ID CRYSTAL-FIELD; TRANSPORT-PROPERTIES; MAGNETIC-FIELD; BEHAVIOR; (LA0.8CA0.2)MNO3; SUPERCONDUCTORS; EXCITATIONS; PEROVSKITE; CHARGE; FILMS AB The specific heat of the colossal magnetoresistance material Nd0.67Sr0.33MnO3 is reported for 0.35 less than or equal to T less than or equal to 280 K, H=0 and 1 less than or equal to T less than or equal to 120 K, H=9 T. The results include a Schottky-like specific-heat anomaly for the Nd ordering, an "attenuation" of the Mn ordering anomaly, and a T-dependent "linear term," gamma(T)T. This unusual combination of features is interpreted as arising from an interaction between the Nd and Mn spin systems. The expected magnetic entropy is recovered only if a contribution from the gamma(T)T term is included. [S0163-1829(99)03501-8]. C1 Amherst Coll, Dept Phys, Amherst, MA 01002 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, MSD, Berkeley, CA 94720 USA. RP Gordon, JE (reprint author), Amherst Coll, Dept Phys, Amherst, MA 01002 USA. RI Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 29 TC 101 Z9 103 U1 1 U2 7 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 JAN 1 PY 1999 VL 59 IS 1 BP 127 EP 130 DI 10.1103/PhysRevB.59.127 PG 4 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800034 ER PT J AU Golovanov, V Mihaly, L Homes, CO McCarroll, WH Ramanujachary, KV Greenblatt, M AF Golovanov, V Mihaly, L Homes, CO McCarroll, WH Ramanujachary, KV Greenblatt, M TI Temperature and magnetic field dependent optical spectral weight in the cation-deficient colossal-magnetoresistance material La0.936Mn0.982O3 SO PHYSICAL REVIEW B LA English DT Article ID DOUBLE-EXCHANGE; ELECTRONIC-STRUCTURE; LA1-XSRXMNO3; LA0.5CA0.5MNO3; RESISTIVITY; CHARGE; FILMS; MN AB The optical reflectivity of a vacancy doped colossal magnetoresistance material La0.936Mn0.982O3 has been investigated on single-crystal samples as a function of temperature and at zero and 0.5 T magnetic fields. The conductivity has been evaluated by Kramers-Kronig analysis in the frequency range of 100-20 000 cm(-1) The broad peak in the optical conductivity, observed at room temperature around 10 000 cm(-1), shifts towards zero as the ferromagnetic state develops at lower temperatures. In the transition regime the application of moderate magnetic field also induces a downward shift of the spectral weight. [S0163-1824(99)14401-1]. C1 SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Rutgers State Univ, Dept Chem, Piscataway, NJ 08854 USA. RP Golovanov, V (reprint author), SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. NR 24 TC 5 Z9 5 U1 0 U2 0 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 JAN 1 PY 1999 VL 59 IS 1 BP 153 EP 156 DI 10.1103/PhysRevB.59.153 PG 4 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800041 ER PT J AU Gapud, AA Wu, JZ Kang, BW Yan, SL Xie, YY Siegal, MP AF Gapud, AA Wu, JZ Kang, BW Yan, SL Xie, YY Siegal, MP TI Giant T-c shift in HgBa2CaCu2O6+delta and TlBa2CaCu2O7-delta superconductors due to Hg-Tl exchange SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; IRREVERSIBILITY LINE; MAGNETIC-FIELDS; THIN-FILMS; RESISTIVE TRANSITION; SINGLE-CRYSTALS; O SYSTEM; HGBA2CA2CU3O8+DELTA; HGBA2CUO4+DELTA; ENHANCEMENT AB The irreversibility lines of epitaxial thin films of HgBa2CaCu2O6+delta and TlBa2CaCu2O7-delta, whether deduced from field-induced magnetoresistive broadening or onset of nonhysteretic magnetization, were found to coincide when plotted against reduced temperature, showing the same exponential-decay temperature behavior for T/T-c < 0.8 and power-law behavior for T/T-c > 0.8 (where T-c is zero-field, zero-resistivity critical temperature). These results indicate that replacing Tl with Hg has no noticeable effect on the anisotropy and suggests that T-c is not determined by anisotropy. [S0163-1829(99)04601-9]. C1 Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gapud, AA (reprint author), Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. EM gapud@ukans.edu OI Gapud, Albert/0000-0001-9048-9230 NR 32 TC 12 Z9 12 U1 0 U2 0 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 JAN 1 PY 1999 VL 59 IS 1 BP 203 EP 206 DI 10.1103/PhysRevB.59.203 PG 4 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800054 ER PT J AU Jorgensen, JD Hu, Z Teslic, S Argyriou, DN Short, S Evans, JSO Sleight, AW AF Jorgensen, JD Hu, Z Teslic, S Argyriou, DN Short, S Evans, JSO Sleight, AW TI Pressure-induced cubic-to-orthorhombic phase transition in ZrW2O8 SO PHYSICAL REVIEW B LA English DT Article ID NEGATIVE THERMAL-EXPANSION AB The crystal structure of ZrW2O8 and its variation with pressure and temperature have been investigated by in situ neutron powder diffraction. At room temperature, the cubic ct phase is stable below 0.21 GPa, where a first-order transition to the orthorhombic gamma phase, accompanied by a 4.95% reduction in volume occurs. The transition involves the inversion of one third of the W2O8 units, which is made possible by the migration of oxygen atoms that are bonded to only one W atom in the cubic phase. WO4 tetrahedra tilt off the threefold axes of the cubic cell and oxygen atoms that are coordinated to only one W atom in the cubic phase become coordinated to two W atoms in the orthorhombic phase. In spite of its smaller volume, the orthorhombic phase has a volume compressibility [(Delta V/Delta P)/V= -1.53(1) x 10(-2) GPa(-1)] that is slightly larger than that of the cubic phase [-1.38(1) x 10(-2) GPa(-1)]. This appears to result from a larger contribution of coordinated tilting of the ZrO6 octahedra and WOn polyhedra to the compression. The orthorhombic phase is retained upon release of pressure. Below room temperature, the metastable orthorhombic phase exhibits an average negative volume thermal expansion [(Delta V/Delta T)/V] of -3.4 x 10(-6) K-1, which is an order of magnitude smaller than that for the cubic phase (-2.6 x 10(-5) K-1), apparently because of the reduced framework flexibility of the orthorhombic phase. Above room temperature, the thermal expansion of the orthorhombic phase becomes positive, prior to a first-order transition back to the cubic phase that occurs at about 390 K. [S0163-1829(99)01401-0]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Oxford, Oxford OX1 3QR, England. Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. RP Jorgensen, JD (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Evans, John/E-6345-2012 OI Evans, John/0000-0001-6305-6341 NR 18 TC 116 Z9 123 U1 1 U2 23 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 JAN 1 PY 1999 VL 59 IS 1 BP 215 EP 225 DI 10.1103/PhysRevB.59.215 PG 11 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800057 ER PT J AU Fisher, IR Cheon, KO Panchula, AF Canfield, PC Chernikov, M Ott, HR Dennis, K AF Fisher, IR Cheon, KO Panchula, AF Canfield, PC Chernikov, M Ott, HR Dennis, K TI Magnetic and transport properties of single-grain R-Mg-Zn icosahedral quasicrystals [R = Y, (Y1-xGdx), (Y1-xTbx), Tb, Dy, Ho, and Er] SO PHYSICAL REVIEW B LA English DT Article ID SPIN-GLASSES; QUASI-CRYSTALS; PHASE-DIAGRAM; TEMPERATURE; SUSCEPTIBILITY; CONDUCTIVITY; AL70MN9PD21 AB We report measurements of the de magnetization, the low-held ac magnetic susceptibility, and the electrical resistivity of large (up to 0.5 cm(3)) single-grain samples of icosahedral R-Mg-Zn (R = Y, Tb, Dy, Ho, and Er). The dc magnetization and ac magnetic susceptibility data both indicate that icosahedral Tb-Mg-Zn and Dy-Mg-Zn undergo a transition to a spin-glass state at T-f = 5.8 and 3.6 K, respectively, while low-temperature ac susceptibility measurements show that T-f = 1.95 and 1.3 K for Ho-Mg-Zn and Er-Mg-Zn, respectively. For the series of solid solutions (Y1-xTbx)-Mg-Zn, the freezing temperature T-f varies approximately as x(2/3). The (Y1-xGdx)-Mg-Zn solid solutions have lower T-f values than (Y1-xTbx)-Mg-Zn for the same magnetic rare-earth concentrations (x), indicating that local moment anisotropy caused by crystalline electric-field effects plays a significant role in increasing T-f. On the other hand, angular-dependent studies show that the de magnetization for T > T-f is isotropic within the experimental uncertainty. The electrical resistivity rho(T) of the single-grain samples is only weakly temperature dependent, with a small, negative d rho/dT. Absolute values of the resistivity fall in the range between 150 and 200 mu Omega cm, which is distinctly lower than the values previously reported for other thermodynamically stable icosahedral quasicrystals. [S0163-1829(99)05801-4]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. ETH Honggerberg, Festkorperphys Lab, CH-8093 Zurich, Switzerland. RP Fisher, IR (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 30 TC 86 Z9 88 U1 1 U2 12 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 JAN 1 PY 1999 VL 59 IS 1 BP 308 EP 321 DI 10.1103/PhysRevB.59.308 PG 14 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800068 ER PT J AU Jauch, W Schultz, AJ Stewart, RF AF Jauch, W Schultz, AJ Stewart, RF TI Anharmonicity in thermal motion and electrostatic forces on nuclei: Pulsed neutron diffraction from MnF2 SO PHYSICAL REVIEW B LA English DT Article ID CRYSTALS AB Antiferromagnetic order in MnF2 induces a sharp polarization of the fluorine core electron shell. The dipolar core-deformation generates a sizable electric field at the nuclear site, thus giving rise to an apparent Coulomb force on the nucleus, which is not compensated by peripheral lattice contributions. A local source of an opposing electric field is proposed, consisting in a small skewness of the fluorine nuclear vibrational distribution. Pulsed single-crystal neutron diffraction (T = 15 K) at the spallation source IPNS has been used to test the hypothesis. Data have been collected up to very high diffraction vectors, (sin Theta/lambda)(max)=2.75 Angstrom(-1), and statistically significant anharmonic parameters could be extracted. Though the predicted value for the electric field could not be confirmed quantitatively, the presence of anharmonicity at low temperature has been clearly established. The shape of the fluorine nuclear distribution function supports a subtle balance between the mean thermal electric fields caused by the electronic and the nuclear charge density distributions. The sense of the skewness around the equilibrium position is opposite to the one found for the paramagnetic state. [S0163-1829(98)07245-2]. C1 Hahn Meitner Inst, D-14109 Berlin, Germany. Argonne Natl Lab, IPNS Div, Argonne, IL 60439 USA. Carnegie Mellon Univ, Dept Chem, Pittsburgh, PA 15213 USA. RP Jauch, W (reprint author), Hahn Meitner Inst, Glienicker Str 100, D-14109 Berlin, Germany. NR 21 TC 7 Z9 7 U1 0 U2 1 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 JAN 1 PY 1999 VL 59 IS 1 BP 373 EP 380 DI 10.1103/PhysRevB.59.373 PG 8 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800077 ER PT J AU James, P Eriksson, O Johansson, B Abrikosov, IA AF James, P Eriksson, O Johansson, B Abrikosov, IA TI Calculated magnetic properties of binary alloys between Fe, Co, Ni, and Cu SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METAL IMPURITIES; ELECTRONIC-STRUCTURE; BAND THEORY; PRINCIPLES CALCULATIONS; FINITE-TEMPERATURE; SURFACE MAGNETISM; SPIN DYNAMICS; INVAR; IRON; BCC AB We present a detailed theoretical investigation of the magnetic properties of all the binary alloys between the 3d elements Fe, Co, Ni, and Cu, in the fee, bcc, and hcp structures using the coherent-potential approximation in combination with a linear muffin-tin orbitals basis set. We consider random, ordered, and partially ordered alloys. Theory is shown to successfully reproduce the magnetic properties of these alloys, and allows an understanding of the physics of the formation of magnetic moments in these systems. We have investigated the correlation between magnetism and local chemical and magnetical surrounding, and find that Fe and Ni display rather different behavior. Our study shows that there is an alloy-induced high-spin-low-spin magnetic phase transition in all Fe-based fee and hcp alloys. The limitations of a collinear spin model and the Weiss model for explaining the Invar effect are discussed on basis of noncollinear calculations for fee Fe. [S0163-1829(98)03146-4]. C1 Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, S-75121 Uppsala, Sweden. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, S-75121 Uppsala, Sweden. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 69 TC 116 Z9 116 U1 3 U2 25 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 JAN 1 PY 1999 VL 59 IS 1 BP 419 EP 430 DI 10.1103/PhysRevB.59.419 PG 12 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800082 ER PT J AU Tishin, AM Gschneidner, KA Pecharsky, VK AF Tishin, AM Gschneidner, KA Pecharsky, VK TI Magnetocaloric effect and heat capacity in the phase-transition region SO PHYSICAL REVIEW B LA English DT Article ID GADOLINIUM COMPOUNDS AB The behavior of the magnetic-field and temperature-dependent heat capacity C(H,T) and the magnetocaloric effect Delta T(Delta H,T), in the vicinity of magnetic phase transitions is discussed. A simple model allowing calculation of the peak value of the magnetocaloric effect is developed from general principles of thermodynamics. It is shown that a characteristic temperature Theta(H) where the heat capacity of the magnetic material is independent of the magnetic field, can be defined. The peak value (maximum or minimum) of the magnetocaloric effect occurs near the Theta(H). Both Theta(H) and peak value of the magnetocaloric effect approach the magnetic ordering temperature. Experimental measurements of the heat capacity and the magnetocaloric effect of several high-purity lanthanide magnetic materials agree well the theoretical model. [S0163-1829(99)07101-5]. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. Moscow MV Lomonosov State Univ, Dept Phys, Moscow 119899, Russia. RP Pecharsky, VK (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM Vitkp@AmesLab.gov RI Tishin, Alexander/E-8705-2014 OI Tishin, Alexander/0000-0003-2252-7279 NR 23 TC 79 Z9 81 U1 4 U2 19 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 JAN 1 PY 1999 VL 59 IS 1 BP 503 EP 511 DI 10.1103/PhysRevB.59.503 PG 9 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800094 ER PT J AU Metlushko, V Welp, U Crabtree, GW Zhang, Z Brueck, SRJ Watkins, B DeLong, LE Ilic, B Chung, K Hesketh, PJ AF Metlushko, V Welp, U Crabtree, GW Zhang, Z Brueck, SRJ Watkins, B DeLong, LE Ilic, B Chung, K Hesketh, PJ TI Nonlinear flux-line dynamics in vanadium films with square lattices of submicron holes SO PHYSICAL REVIEW B LA English DT Article ID INTERFEROMETRIC LITHOGRAPHY; SUPERCONDUCTING FILMS; ARRAYS; MULTILAYERS; VORTICES; FIELD; DEFECTS; MICROHOLES AB Commensurability effects between the superconducting flux-line lattice and a square lattice (period d = 1 mu m) of submicron holes (diameter D = 0.4 mu m) in 1500 Angstrom vanadium films were studied by atomic-force microscopy, de magnetization, ac susceptibility, magnetoresistivity, and I-V measurements. Peaks in the susceptibility and critical current at matching fields are found to depend nonlinearly upon the value of external ac field or current, as well as the inferred symmetry of the flux-line lattice. [S0163-1829(99)44201-0]. C1 Argonne Natl Lab, MSD, Argonne, IL 60439 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Univ Kentucky, Lexington, KY 40506 USA. Univ Illinois, EECS, Chicago, IL 60607 USA. RP Metlushko, V (reprint author), Argonne Natl Lab, MSD, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Brueck, Steven/A-6383-2013; Ilic, Rob/N-1359-2014; OI Brueck, Steven/0000-0001-8754-5633 NR 33 TC 62 Z9 62 U1 0 U2 1 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 JAN 1 PY 1999 VL 59 IS 1 BP 603 EP 607 DI 10.1103/PhysRevB.59.603 PG 5 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800107 ER PT J AU Birmingham, JT Grannan, SM Richards, PL Kircher, J Cardona, M Wittlin, A AF Birmingham, JT Grannan, SM Richards, PL Kircher, J Cardona, M Wittlin, A TI Optical absorptivity of La1.87Sr0.13CuO4 below the superconducting plasma edge SO PHYSICAL REVIEW B LA English DT Article ID FAR-INFRARED MEASUREMENT; C-AXIS RESPONSE; ENERGY-GAP; CUPRATE SUPERCONDUCTORS; LA2-XSRXCUO4; LA1.85SR0.15CUO4; CONDUCTIVITY; BOLOMETERS; DYNAMICS AB We have directly measured the far-infrared absorptivity of single crystal La1.87Sr0.13CuO4 at 2 K for radiation between 6 and 420 cm(-1) polarized along the c axis. We have computed the dielectric functions epsilon(c)(omega) and conductivity sigma(c)(omega) using a Kramers-Kronig analysis. The existence of nonzero losses below the plasma edge and down to the lowest frequency measured is consistent with a model of a superconducting gap with nodes. From the calculation of epsilon(c)(omega), We deduce a value of 230 +/- 10 cm(-1) for the unscreened plasma frequency in the superconducting state. A small peak in the sigma(1)(c)(omega) is seen near 10 cm(-1). [S0163-1829(99)04701-3]. C1 Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. RP Birmingham, JT (reprint author), Brandeis Univ, Volen Ctr Complex Syst, Waltham, MA 02454 USA. RI Wittlin, Aleksander/A-2337-2017 NR 32 TC 2 Z9 2 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 JAN 1 PY 1999 VL 59 IS 1 BP 647 EP 653 DI 10.1103/PhysRevB.59.647 PG 7 WC Physics, Condensed Matter SC Physics GA 155JR UT WOS:000077943800113 ER PT J AU Schultz, PA Leung, K Stechel, EB AF Schultz, PA Leung, K Stechel, EB TI Small rings and amorphous tetrahedral carbon SO PHYSICAL REVIEW B LA English DT Article ID DENSITY-FUNCTIONAL THEORY; DIAMOND-LIKE CARBON; ELECTRONIC-PROPERTIES; PERTURBATION-THEORY; MOLECULAR-DYNAMICS; NEUTRON-SCATTERING; EFFECTIVE CHARGES; GROUND-STATE; PRESSURE; SILICON AB We apply first-principles density-functional calculations to study strain in dense amorphous tetrahedral carbon(a-tC). While the large strain present in small-ring structures? particularly three-member rings, could argue against their existence in a-tC, we demonstrate, based on energetic arguments, that strained small (three- and four-member) rings are plausible topological microstructural elements. We present two bulk carbon structures made up entirely of fourfold-coordinated atoms: the first with every atom in one three-member ring, the second with every atom in one four-member ring. Calculations show these bulk ring structures are relatively low in energy, only 0.37 and 0.23 eV/atom above diamond, respectively. This computed strain energy is much less than that present in recent models for a-tC. We examine properties of these structures with the intention to provide benchmark calculations for more approximate models, and to investigate the impact small rings might have on the properties of a-tC. We use a recently developed linear-response algorithm to compute phonon spectra for these ring structures. [S0163-1829(99)02901-X]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Stechel, Ellen/B-1253-2012 NR 50 TC 28 Z9 29 U1 0 U2 5 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 JAN 1 PY 1999 VL 59 IS 2 BP 733 EP 741 DI 10.1103/PhysRevB.59.733 PG 9 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600014 ER PT J AU Tostmann, H DiMasi, E Pershan, PS Ocko, BM Shpyrko, OG Deutsch, M AF Tostmann, H DiMasi, E Pershan, PS Ocko, BM Shpyrko, OG Deutsch, M TI Surface structure of liquid metals and the effect of capillary waves: X-ray studies on liquid indium SO PHYSICAL REVIEW B LA English DT Article ID ALKALI-METALS; REFLECTIVITY; GALLIUM; ELECTRON; INTERFACES; FILMS AB We report x-ray reflectivity (XR) and small-angle off-specular diffuse-scattering (DS) measurements from the surface of liquid indium close to its melting point of 156 degrees C. From the XR measurements we extract the surface structure factor convolved with fluctuations in the height of the liquid surface. We present a model to describe DS that takes into account the surface structure factor, thermally excited capillary waves, and the experimental resolution. The experimentally determined DS follows this model with no adjustable parameters, allowing the surface structure factor to be deconvolved from the thermally excited height fluctuations. The resulting local electron-density profile displays exponentially decaying surface-induced layering similar to that previously reported for Ga and Hg. We compare the details of the local electron-density profiles of liquid In, which is a nearly free-electron metal, and liquid Ga, which is considerably more covalent and shows directional bonding in the melt. The oscillatory density profiles have comparable amplitudes in both metals, but surface layering decays over a length scale of 3.5+/-0.6 Angstrom for In and 5.5+/-0.4 Angstrom for Ga. Upon controlled exposure to oxygen, no oxide monolayer is formed on the liquid In surface, unlike the passivating film formed on liquid gallium. [S0163-1829(99)11701-6]. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. RP Tostmann, H (reprint author), Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RI Shpyrko, Oleg/J-3970-2012 NR 43 TC 107 Z9 109 U1 1 U2 11 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 JAN 1 PY 1999 VL 59 IS 2 BP 783 EP 791 DI 10.1103/PhysRevB.59.783 PG 9 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600019 ER PT J AU Xie, JJ de Gironcoli, S Baroni, S Scheffler, M AF Xie, JJ de Gironcoli, S Baroni, S Scheffler, M TI First-principles calculation of the thermal properties of silver SO PHYSICAL REVIEW B LA English DT Article ID THERMODYNAMIC PROPERTIES; EXPANSION; SEMICONDUCTORS; DIAMOND; METALS; DYNAMICS; MODEL AB The thermal properties of silver are calculated within the quasiharmonic approximation, by using phonon dispersions from density-functional perturbation theory, and the pseudopotential plane-wave method. The resulting free energy provides predictions for the temperature dependence of various quantities such as the equilibrium lattice parameter, the bulk modulus, and the heat capacity. Our results for the thermal properties are in good agreement with available experimental data in a wide range of temperatures. As a by-product, we calculate phonon frequency and Gruneisen parameter dispersion curves which are also in good agreement with experiment. [S0163-1829(99)00702-X]. C1 Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. Scuola Int Super Studi Avanzati, I-34014 Trieste, Italy. Ist Nazl Fis Mat, I-34014 Trieste, Italy. ENS, Ctr Europeen Calcul Atom & Mol, F-69007 Lyon, France. RP Xie, JJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-11,MS-B262, Los Alamos, NM 87545 USA. EM xie@viking.lanl.gov RI de Gironcoli, Stefano/G-7236-2011; Baroni, Stefano/F-2982-2011; Scheffler, Matthias/O-4649-2016 OI de Gironcoli, Stefano/0000-0002-2307-0998; Baroni, Stefano/0000-0002-3508-6663; NR 29 TC 96 Z9 99 U1 0 U2 14 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 JAN 1 PY 1999 VL 59 IS 2 BP 965 EP 969 DI 10.1103/PhysRevB.59.965 PG 5 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600037 ER PT J AU Xie, JJ de Gironcoli, S Baroni, S Scheffler, M AF Xie, JJ de Gironcoli, S Baroni, S Scheffler, M TI Temperature-dependent surface relaxations of Ag(111) SO PHYSICAL REVIEW B LA English DT Article ID ANOMALOUS THERMAL-EXPANSION; SCATTERING AB The temperature-dependent surface relaxation of Ag(lll) is calculated by density-functional theory. At a given temperature, the equilibrium geometry is determined by minimizing the Helmholtz free energy within the quasiharmonic approximation. To this end, phonon dispersions all over the Brillouin zone are determined from density-functional perturbation theory. We find that the top-layer relaxation of Ag(lll) changes from an inward contraction (-0.8%) to an outward expansion (+6.3%) as the temperature increases from T=0 K to 1150 K, in agreement with experimental findings. Also, the calculated surface phonon dispersion curves at room temperature are in good agreement with helium-scattering measurements. The mechanism driving this surface expansion is analyzed, and the physical picture developed by Narasimhan and Scheffler is essentially confirmed. [S0163-1829(99)00502-0]. C1 Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. Scuola Int Super Studi Avanzati, I-34014 Trieste, Italy. Ist Nazl Fis Mat, I-34014 Trieste, Italy. ENS, Ctr Euroeen Calcul Atom & Mol, F-69007 Lyon, France. RP Xie, JJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-11,MS-B262, Los Alamos, NM 87545 USA. EM xie@viking.lanl.gov RI de Gironcoli, Stefano/G-7236-2011; Baroni, Stefano/F-2982-2011; Scheffler, Matthias/O-4649-2016 OI de Gironcoli, Stefano/0000-0002-2307-0998; Baroni, Stefano/0000-0002-3508-6663; NR 23 TC 44 Z9 44 U1 1 U2 4 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 JAN 1 PY 1999 VL 59 IS 2 BP 970 EP 974 DI 10.1103/PhysRevB.59.970 PG 5 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600038 ER PT J AU Matsuda, M Yosihama, T Kakurai, K Shirane, G AF Matsuda, M Yosihama, T Kakurai, K Shirane, G TI Quasi-two-dimensional hole ordering and dimerized state in the CuO2-chain layers in Sr14CU24O41 SO PHYSICAL REVIEW B LA English DT Article ID SINGLET-GROUND-STATE; SPIN-PEIERLS COMPOUND; MAGNETIC EXCITATIONS; NEUTRON-SCATTERING; CUO2 CHAINS; GAP; TEMPERATURE; LADDERS; SYSTEM; SUSCEPTIBILITY AB Neutron-scattering experiments have been performed on Sr14Cu24O41 that consists of both chains and ladders of copper ions. We observed that the magnetic excitations from the CuO2 chain have two branches and that both branches are weakly dispersive along the a and c axes. The omega-Q dispersion relation as well as the intensities can be reasonably described by a random-phase approximation with intradimer coupling J = 11 meV, interdimer coupling along the c axis J(c)=0.75 meV, and interdimer coupling along the a axis J(a)=0.75 meV. The dimer configuration indicates a quasi-two-dimensional hole ordering, resulting in an ordering of magnetic Cu2+ With spin-1/2 and nonmagnetic Cu, which forms the Zhang-Rice singlet. We have also studied the effect of Ca substitution for Sr on the dimer and the hole ordering. [S0163-1829(99)11401-2]. C1 RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. Univ Tokyo, ISSP, Neutron Scattering Lab, Tokai, Ibaraki 3191106, Japan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Matsuda, M (reprint author), RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. RI Matsuda, Masaaki/A-6902-2016 OI Matsuda, Masaaki/0000-0003-2209-9526 NR 44 TC 58 Z9 58 U1 0 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 JAN 1 PY 1999 VL 59 IS 2 BP 1060 EP 1067 DI 10.1103/PhysRevB.59.1060 PG 8 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600050 ER PT J AU Myers, KD Canfield, PC Kalatsky, VA Pokrovsky, VL AF Myers, KD Canfield, PC Kalatsky, VA Pokrovsky, VL TI Angular dependence of metamagnetic transitions in DyAgSb2 SO PHYSICAL REVIEW B LA English DT Article ID EARTH AB Measurements;of the magnetization of DyAgSb2 reveal a complex system of up to 11 well-defined metamagnetic states for the field applied within the basal plane. Measurements of the magnetization vs the angle the applied field makes with respect to the [110] axis show the Dy3+ moments are constrained to lie along one of the four [110] directions within the basal plane. From the angular dependence of the critical fields and plateau magnetizations, the net distribution of the moments may be deduced for each state. Finally, the coupling constants are calculated within the framework of the "four-position clock model." [S0163-1829(99)04302-7]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. RP Myers, KD (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 12 TC 18 Z9 18 U1 0 U2 2 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 JAN 1 PY 1999 VL 59 IS 2 BP 1121 EP 1128 DI 10.1103/PhysRevB.59.1121 PG 8 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600055 ER PT J AU Lawrence, JM Osborn, R Sarrao, JL Fisk, Z AF Lawrence, JM Osborn, R Sarrao, JL Fisk, Z TI Time-of-flight neutron-scattering study of YbInCu4 and YbIn0.3Ag0.7Cu4 SO PHYSICAL REVIEW B LA English DT Article ID VALENCE ALLOY CE1-XTHX; SINGLE-CRYSTAL; PHASE-TRANSITION; YBIN1-XAGXCU4; BEHAVIOR; SPECTRA; CEPD3; CE AB We report neutron-scattering experiments for YbInCu4 that were performed in the time-of-flight mode at a neutron spallation source. Two independent methods were used to determine the nonmagnetic scattering and both gave comparable results for the magnetic scattering. The magnetic scattering was measured at temperatures T= 30 and 60 K, below and above the temperature of the valence transition T-s=40 K. Our key result is that the spin dynamics in the mixed valent phase are well described over a broad range of energy transfer (10< Delta E< 150 meV) and incident energies (35 less than or equal to E(i)less than or equal to 150 meV) by a Lorentzian power spectrum, centered at E(0)similar or equal to 40 meV, and with halfwidth Gamma congruent to 13 meV. The magnetic susceptibility derived from the fits is within 20% of the value measured for the de susceptibility. The peak energy is in good agreement with the Kondo temperature derived from thermodynamic studies but the Lorentzian line shape fits the data significantly better (chi(2)congruent to 2) than the line shape expected for a Kondo impurity (chi(2)congruent to 10). In addition we report results for YbIn0.3Ag0.7Cu4. For this compound, the scattering is inelastic at low temperature (at 10 K E-0= 7.4 meV, and Gamma=7.6 meV) but is quasielastic at higher temperature where Gamma=10.0 and 13.2 meV at 150 and 300 K, respectively. This increase in linewidth is contrary to the 50% decrease in linewidth predicted by the Anderson impurity model for this temperature range, and is also smaller than the factor of four increase in characteristic energy suggested by application of the impurity model to the magnetic susceptibility. [S0163-1829(99)04002-3]. C1 Univ Calif Irvine, Irvine, CA 92697 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Florida State Univ, Tallahassee, FL 32306 USA. RP Lawrence, JM (reprint author), Univ Calif Irvine, Irvine, CA 92697 USA. RI Osborn, Raymond/E-8676-2011 OI Osborn, Raymond/0000-0001-9565-3140 NR 19 TC 25 Z9 25 U1 0 U2 0 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 JAN 1 PY 1999 VL 59 IS 2 BP 1134 EP 1140 DI 10.1103/PhysRevB.59.1134 PG 7 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600057 ER PT J AU Wada, H Hundley, MF Movshovich, R Thompson, JD AF Wada, H Hundley, MF Movshovich, R Thompson, JD TI Pressure effect on the valence transition of EuNi2(Ge1-xSix)(2) SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; EU AB The temperature dependence of electrical resistivity rho has been measured for EuNi2(Ge1-xSix), with 0.0 less than or equal to x less than or equal to 0.15 at pressures to 15 kbar. At ambient pressure, all the compounds are antiferromagnetic with stable Eu2+ moments, but compounds with 0.10 less than or equal to x less than or equal to 0.15 show a pressure-induced valence transition. Just above a critical pressure, the compound undergoes a first-order valence transition. With further increase in pressure, the valence transition becomes continuous. The temperature dependence of rho is discussed by regarding the system as a virtual alloy of Eup22+Eup33+, where p(2) and p(3) are the occupation probabilities of Eu2+ and Eu3+ states, respectively. We argue that impurity scattering due to randomness in a virtual alloy is responsible for the temperature dependence of rho in this system. By combining the present results with previous determinations of the pressure dependence of the tetragonal unit-cell volume, a generalized pressure-temperature phase diagram of EuNi2Ge2 is established which indicates that applying pressure is equivalent to Si doping in EuNi2Ge2. [S0163-1829(99)07201-X]. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Kyoto Univ, Dept Mat Sci & Engn, Sakyo Ku, Kyoto 6068501, Japan. RP Wada, H (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 8 TC 36 Z9 36 U1 1 U2 10 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 JAN 1 PY 1999 VL 59 IS 2 BP 1141 EP 1144 DI 10.1103/PhysRevB.59.1141 PG 4 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600058 ER PT J AU Jenniches, H Shen, J Mohan, CV Manoharan, SS Barthel, J Ohresser, P Klaua, M Kirschner, J AF Jenniches, H Shen, J Mohan, CV Manoharan, SS Barthel, J Ohresser, P Klaua, M Kirschner, J TI Structure and magnetism of pulsed-laser-deposited ultrathin films of Fe on Cu(100) SO PHYSICAL REVIEW B LA English DT Article ID THIN-FILMS; FCC-FE; EPITAXIAL-GROWTH; INTENSITY OSCILLATIONS; FE/CU(100); SURFACE; TEMPERATURE; ANISOTROPY; IRON; MORPHOLOGY AB A layer-by-layer growth of ultrathin films right from the beginning would be desirable for establishing a straightforward correlation between magnetism and structure. We give experimental evidence that with the help of pulsed laser deposition (PLD) we can achieve layer-by-layer growth for Fe on Cu(100) in contrast to deposition by molecular-beam epitaxy. We present the results of a comprehensive study of the structural and magnetic properties of PLD-grown ultrathin Fe films of thicknesses between 2 and 10 monolayers (ML) deposited at room temperature. We show scanning tunneling microscopy images and low-energy electron-diffraction (LEED) patterns as well as intensity vs energy (IV) LEED curves demonstrating that PLD-grown Fe/Cu(100) has an isotropic fee structure. We characterize the magnetic properties of our films by the magnetooptical Ken effect. Following the improved growth and morphology, we found strong differences in the magnetic behavior of these films in comparison with Fe thermally deposited onto Cu(100): PLD-grown ultrathin Fe/Cu(100) shows an in-plane easy axis of magnetization in the thickness range 2-5 ML and again from about 10 ML. where the film structure is dominated by the bcc-Fe bulk phase, while there is a perpendicular easy axis of magnetization between 7 and 10 ML coverage. These results are discussed in terms of the different growth and structure due to the characteristic features of the PLD technique. [S0163-1829(99)13201-6]. C1 Max Planck Inst Mikrostrukturphys, D-06120 Halle, Germany. RP Shen, J (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 61 TC 65 Z9 65 U1 4 U2 17 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 JAN 1 PY 1999 VL 59 IS 2 BP 1196 EP 1208 DI 10.1103/PhysRevB.59.1196 PG 13 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600066 ER PT J AU Shimakawa, Y Kubo, Y Hamada, N Jorgensen, JD Hu, Z Short, S Nohara, M Takagi, H AF Shimakawa, Y Kubo, Y Hamada, N Jorgensen, JD Hu, Z Short, S Nohara, M Takagi, H TI Crystal structure, magnetic and transport properties, and electronic band structure of A(2)Mn(2)O(7) pyrochlores (A = Y, In, Lu, and Tl) SO PHYSICAL REVIEW B LA English DT Article ID COLOSSAL MAGNETORESISTANCE; GIANT MAGNETORESISTANCE; DOUBLE EXCHANGE; TL2MN2O7; Y2MN2O7; FILMS; LA1-XSRXMNO3; RESISTIVITY; ORDER; LIMIT AB Crystal structures, magnetic and transport properties, and electronic band structures for four compounds with the pyrochlore structure, Tl2Mn2O7, which exhibits colossal magnetoresistive behavior, and insulating A(2)Mn(2)O(7) (A = Y, In and Lu), are discussed. The cubic unit cell dimensions increase with increasing ionic size of the A(3+) ions. The ferromagnetic behavior is consistent with a superexchange interaction of Mn4+ spins with an intermediate Mn-O-Mn bond angle of about 130 degrees. In In2Mn2O7 and Tl2Mn2O7, strong hybridization of the In(5s)/Tl(6s) orbital with O(2p) and Mn(3d) may enhance the ferromagnetic interaction, leading to high transition temperatures over 120 K. The metallic behavior of Tl2Mn2O7 also originates from the hybridization among Tl(6s), O(2p), and Mn(3d). The free-electron-like minority down-spin band crosses the Fermi energy, leading to spin-polarized conduction. At the ferromagnetic Curie temperature, where majority local spins align, spin-polarized conduction electrons are produced: Thus, a ferromagnetic-and-metallic state appears in the Tl2Mn2O7 pyrochlore. [S0163-1829(99)00602-5]. C1 NEC Corp Ltd, Fundamental Res Labs, Tsukuba, Ibaraki 3058501, Japan. Sci Univ Tokyo, Fac Sci & Technol, Dept Phys, Noda, Chiba 2788510, Japan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 1066888, Japan. RP Shimakawa, Y (reprint author), NEC Corp Ltd, Fundamental Res Labs, 34 Miyukigaoka, Tsukuba, Ibaraki 3058501, Japan. RI Takagi, Hidenori/B-2935-2010; NOHARA, Minoru/B-1476-2011; KUBO, Yoshimi/H-2851-2011 NR 36 TC 65 Z9 65 U1 2 U2 19 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 JAN 1 PY 1999 VL 59 IS 2 BP 1249 EP 1254 DI 10.1103/PhysRevB.59.1249 PG 6 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600072 ER PT J AU van Veenendaal, M Fedro, AJ AF van Veenendaal, M Fedro, AJ TI Influence of double occupancy and lattice distortions on the magnetic phase diagram of A(1-x)A(x)' MnO3 SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; MAGNETORESISTANCE; TRANSITION; SUPEREXCHANGE; LA1-XSRXMNO3; PR1-XSRXMNO3; LA1-XCAXMNO3; PEROVSKITES; LAMNO3; OXIDES AB A model is presented that describes the competition between the ferromagnetic and several antiferromagnetic structures observed in the A(1-x)A(x)'MnO3 series. It is found that the strong asymmetry of the magnetic phase diagram, i.e., predominantly ferromagnetic for x<0.5 and antiferromagnetic for x>0.5, can readily be explained by extending the double exchange model to include double occupancy. The strong charge fluctuations between different MnO6 clusters are the result of the charge-transfer-like nature of the manganites. The dependence of the magnetic structure on lattice distortions is described. The appearance of different magnetic structures around x=0.5 is interpreted in terms of changes in the Mn-O-Mn bond angle and the Jahn-Teller distortions. [S0163-1829(99)05501-0]. C1 No Illinois Univ, De Kalb, IL 60115 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP van Veenendaal, M (reprint author), No Illinois Univ, De Kalb, IL 60115 USA. NR 22 TC 11 Z9 11 U1 0 U2 1 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 JAN 1 PY 1999 VL 59 IS 2 BP 1285 EP 1289 DI 10.1103/PhysRevB.59.1285 PG 5 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600077 ER PT J AU Sasik, R Demo, P Kozisek, Z AF Sasik, R Demo, P Kozisek, Z TI Magnetic penetration length and irreversibility of a disordered granular superconductor with pi junctions SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; MEAN-FIELD-THEORY; VECTOR SPIN-GLASS; RENORMALIZATION-GROUP; SK MODEL; SYSTEMS; BI2SR2CACU2O8; EQUATION AB We calculate the magnetic penetration length lambda(T) of a disordered granular superconductor with pi junctions in zero magnetic field, using a mean-field replica method. The superconductor is modeled by an array of Josephson junctions whose couplings are drawn randomly from a Gaussian distribution centered at J(0)>0, with width J. For disorder strength delta=J/J(0)<1 there are three thermodynamical phases of the array separated by continuous transitions: (i) the high-temperature normal phase, (ii) the reversible superconducting phase, and (iii) the low-temperature superconducting glass phase with broken ergodicity. For a range of disorder delta near 1 there is a further possibility of reentry into a low-temperature normal glass phase. For delta greater than or equal to 1 there are only two phases: (i) the high-temperature normal phase and (ii) the low-temperature normal glass phase with broken ergodicity. In the superconducting glass phase we calculate both the Gibbs averaged and the single-state-averaged magnetic penetration lengths. [S0163-1829(99)04702-5]. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Acad Sci Czech Republ, Inst Phys, Prague 16253, Czech Republic. RP Sasik, R (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RI Kozisek, Zdenek/F-7434-2014; Demo, Pavel/H-1432-2014 OI Kozisek, Zdenek/0000-0003-0823-5130; NR 33 TC 0 Z9 0 U1 0 U2 0 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 JAN 1 PY 1999 VL 59 IS 2 BP 1396 EP 1406 DI 10.1103/PhysRevB.59.1396 PG 11 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600091 ER PT J AU Ahrens, ET Heffner, RH Hammel, PC Reyes, AP Thompson, JD Smith, JL Clark, WG AF Ahrens, ET Heffner, RH Hammel, PC Reyes, AP Thompson, JD Smith, JL Clark, WG TI NMR study of U(Be, B)(13) in the normal and superconducting states SO PHYSICAL REVIEW B LA English DT Article ID HEAVY-FERMION SUPERCONDUCTORS; RESONANT IMPURITY SCATTERING; PHASE-TRANSITION; KNIGHT-SHIFT; U1-XTHXBE13; UBE13; FLUCTUATION; RELAXATION; (U,TH)BE13; NUCLEAR AB We report extensive B-11 and Be-9 nuclear magnetic resonance (NMR) spin-lattice relaxation time (T-1) and Knight shift measurements in the heavy-fermion superconductor UBe13-xBx (x= 0.030, 0.067). Data were acquired over a broad temperature (T) range spanning 0.096-300 K in both the normal and superconducting states. In the normal slate, the B-11 T dependence of T-1 displayed several energy scales. In a narrow T range, between 1 and 2 K, 1/T1T was roughly constant. At lower temperatures and in a magnetic field exceeding the upper critical field, 1/T1T exhibited a monotonic decrease down to approximately 0.18 K. Above roughly 4 K, 1/T-1 exhibited a weak T dependence until similar to 60 K. At higher temperatures, additional relaxation mechanisms were present. The 1/T-1 values for both Be-9 and B-11 for all B concentrations were indistinguishable above similar to 4 K; however, at temperatures of the order of 1 K, the x= 0.067 sample had values roughly twice that of the x=0.030 sample for either nuclei. The x=0.030 sample had essentially the same 1/T-1 magnitude and T dependence as undoped UBe13. From the linear plot of the Knight shift (K-B) versus the static magnetic susceptibility (chi), the B-11 hyperfine field coupling constant was calculated to be -361.1 Oe/mu(B). An approximate analysis of the U moment electronic fluctuation rate (T) was performed using the measured values of 1/T-1, K-B, and chi. We observed a Gamma proportional to root T dependence between 8 and 70 K, which is consistent with the existence of isolated local moment fluctuations. For T> 70 K, the Gamma analysis breaks down due to the presence of crystal field excitations. Measurements of 1/T1 indicated a moderate decrease in Gamma with the addition of boron at low temperatures, where T(x= 0.030)lr(x= 0.067)approximate to 2. At lower temperatures, Gamma approached a constant value of the order of 1 meV at T approximate to 2 K. In the superconducting state, the T dependence of 1/T-1 exhibited an absence of power-law behavior and a strong B concentration dependence for both nuclei. This behavior is consistent with gapless superconductivity induced by the B impurities. The ratio of the 9Be to B-11 1/T-1 increased with decreasing T below T-c. This indicates additional contributions to the 9Be 1/T-1 at low temperatures that we attribute to spin diffusion processes that have negligible impact on the dilute B-11. Below T-c, the B-11 Knight shift was measured to be -0.08 (+/-0.01)% and was independent of both x and T. [S0163-1829(99)03602-4]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. RP Ahrens, ET (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM eta@gg.caltech.edu RI Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 49 TC 8 Z9 8 U1 0 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 JAN 1 PY 1999 VL 59 IS 2 BP 1432 EP 1443 DI 10.1103/PhysRevB.59.1432 PG 12 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600096 ER PT J AU Preosti, G Vilk, YM Norman, MR AF Preosti, G Vilk, YM Norman, MR TI Evolution of the pairing pseudogap in the spectral function with interplane anisotropy SO PHYSICAL REVIEW B LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; ATTRACTIVE HUBBARD-MODEL; NORMAL-STATE; ELECTRONIC-STRUCTURE; BI2SR2CACU2O8+DELTA; SUPERCONDUCTORS; GAP AB We study the pairing pseudogap in the spectral function as a function of interplane coupling. The analytical expressions for the self-energy in the critical regime are obtained for any degree of anisotropy. The frequency dependence of Sigma(omega) is found to be qualitatively different in two and three dimensions, and the crossover from two to three dimensional behavior is discussed. In particular, by considering the anisotropy of the Fermi velocity and gap along the Fermi surface, we can qualitatively explain recent photoemission experiments on high temperature superconductors concerning the temperature dependent Fermi arcs seen in the pseudogap phase. [S0163-1829(99)00302-1]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Preosti, G (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Norman, Michael/C-3644-2013 NR 21 TC 14 Z9 14 U1 0 U2 0 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 JAN 1 PY 1999 VL 59 IS 2 BP 1474 EP 1480 DI 10.1103/PhysRevB.59.1474 PG 7 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600099 ER PT J AU Sonier, JE Kiefl, RF Brewer, JH Bonn, DA Dunsiger, SR Hardy, WN Liang, R Miller, RI Noakes, DR Stronach, CE AF Sonier, JE Kiefl, RF Brewer, JH Bonn, DA Dunsiger, SR Hardy, WN Liang, R Miller, RI Noakes, DR Stronach, CE TI Expansion of the vortex cores in YBa2CU3O6.95 at low magnetic fields SO PHYSICAL REVIEW B LA English DT Article ID PENETRATION DEPTH; TEMPERATURE-DEPENDENCE; SUPERCONDUCTORS; STATE; LATTICE; LINES; TC AB Muon-spin-rotation spectroscopy has been used to measure the effective size r(0) of the vortex cores in optimally doped YBa2Cu3O6.95 as a function of temperature T and magnetic field H deep in the superconducting state. While r(0) at H=2 T is close to 20 Angstrom and consistent with that measured by scanning tunneling microscopy at 6 T, we find a striking increase in r(0) at lower magnetic fields, where it approaches an extraordinarily large value of about 100 Angstrom. This suggests that the average value of the superconducting coherence length xi(ab) in cuprate superconductors may be much larger than previously thought at low magnetic fields in the vortex state. [S0163-1829(99)50702-9]. C1 Univ British Columbia, Canadian Inst Adv Res, TRIUMF, Vancouver, BC V6T 1Z1, Canada. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Virginia State Univ, Dept Phys, Petersburg, VA 23806 USA. RP Sonier, JE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 25 TC 31 Z9 31 U1 0 U2 1 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 JAN 1 PY 1999 VL 59 IS 2 BP R729 EP 732 DI 10.1103/PhysRevB.59.R729 PG 4 WC Physics, Condensed Matter SC Physics GA 158JE UT WOS:000078111600013 ER PT J AU Rijken, TA Stoks, VGJ Yamamoto, Y AF Rijken, TA Stoks, VGJ Yamamoto, Y TI Soft-core hyperon-nucleon potentials SO PHYSICAL REVIEW C LA English DT Article ID BARYON-BARYON SCATTERING; P-WAVE BARYONS; QUARK-MODEL; COUPLING-CONSTANTS; PI(+),K+ REACTION; REGGE-POLES; MESON; HYPERNUCLEI; POMERON; PARTICLE AB A new Nijmegen soft-core OBE potential model is presented for the low-energy YN interactions. Besides the results for the fit to the scattering data, which largely defines the model, we also present some applications to hypernuclear systems using the G-matrix method. The potentials are generated by the exchange of nonets of pseudoscalar, vector, and scalar mesons. As is standard in the Nijmegen soft-core models, we also include the J= 0 contributions from the tensor f(2),f(2)',a(2), and pomeron Regge trajectories, and use Gaussian form factors to guarantee that the potentials have a soft behavior near the origin. An important innovation with respect to the original soft-core potential is the assignment of the cutoff masses for the baryon-baryon-meson (BBM) vertices in accordance with broken SU(3)(F), which serves to connect the NN and the YN channels. As a novel feature, we allow for medium strong breaking of the coupling constants, using the P-3(0) model with a Gell-Mann-Okubo hypercharge breaking for the BBM coupling. Charge-symmetry breaking in the Lambda p and Lambda n channels is included as well. We present six hyperon-nucleon potentials which describe the available YN cross section data equally well, but which exhibit some differences on a more detailed level. The differences are constructed such that the models encompass a range of scattering lengths in the Sigma N and Lambda N channels. In all cases, we obtained chi(2)/N(data)approximate to 0.55 for 35 YN data. In particular, we were able to fit the precise experimental datum r(R) =0.468+/-0.010 for the inelastic capture ratio at rest. For the scalar-meson mixing angle we obtained values theta(S)=37 degrees-40 degrees, which points to almost ideal mixing angles for the scalar q (q) over bar states. The G-matrix results indicate that the remarkably different spin-spin terms of the six potentials appear specifically in the energy spectra of Lambda hypernuclei. [S0556-2813(99)04501-X]. C1 Univ Nijmegen, Inst Theoret Phys, Nijmegen, Netherlands. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Adelaide, Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. Tsuru Univ, Phys Sect, Yamanashi 4020054, Japan. RP Univ Nijmegen, Inst Theoret Phys, Nijmegen, Netherlands. NR 100 TC 473 Z9 475 U1 1 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 21 EP 40 DI 10.1103/PhysRevC.59.21 PG 20 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400005 ER PT J AU Friar, JL Huber, D van Kolck, U AF Friar, JL Huber, D van Kolck, U TI Chiral symmetry and three-nucleon forces SO PHYSICAL REVIEW C LA English DT Article ID 2-PION-EXCHANGE 3-NUCLEON FORCES; PERTURBATION-THEORY; LAGRANGIANS; POTENTIALS; THRESHOLD; 3-BODY; MATTER AB After a brief review of the role three-nucleon forces play in the few-nucleon systems, the chiral-perturbation-theory approach to these forces is discussed. Construction of the (nominal) leading- and subleading-order Born terms and pion-rescattering graphs contributing to two-pion-exchange three-nucleon forces is reviewed, and comparisons are made of the types of such forces that are used today. It is demonstrated that the short-range c term of the Tucson-Melbourne force is unnatural in terms of power counting and should be dropped. The cl;lss of two-pion-exchange three-nucleon forces then becomes rather uniform. [S0556-2813(99)02401-2]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. CALTECH, Kellogg Radiat Lab, Pasadena, CA 91125 USA. RP Friar, JL (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 39 TC 176 Z9 178 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 53 EP 58 DI 10.1103/PhysRevC.59.53 PG 6 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400008 ER PT J AU Doring, J Aprahamian, A de Haan, RC Gorres, J Schatz, H Wiescher, M Walters, WB Brown, LT Davids, CN Lister, CJ Seweryniak, D AF Doring, J Aprahamian, A de Haan, RC Gorres, J Schatz, H Wiescher, M Walters, WB Brown, LT Davids, CN Lister, CJ Seweryniak, D TI Radioactive decay of Y-80 and low-lying states in Sr-80 SO PHYSICAL REVIEW C LA English DT Article ID HIGH-SPIN STATES; NUCLEAR-CHARGE RADII; TRANSITION STRENGTHS; LASER SPECTROSCOPY; STRONTIUM ISOTOPES; PARITY ASSIGNMENTS; ROTATIONAL BANDS; LEVEL STRUCTURE; GAMMA-SOFTNESS; T-Z=1 NUCLEI AB The beta(+)/EC decay of a mass-separated Y-80 source has been studied by beta- and gamma-ray spectroscopy following the bombardment of a thin Mg-24 target with Ni-58 ions at 190 MeV. An extended decay scheme with 14 new states in Sr-80 has been identified including the first observation of negative-parity states. The low-lying positive-parity states have been found to be clustered indicating a pattern of one-, two-, and possibly three-phonon multiplets characteristic of an anharmonic vibrator. Some states in Sr-80,an also be grouped into a gamma-vibrational band. In general the low-lying states in light strontium isotopes show vibrationlike collectivity which evolves to rotational behavior with increasing spin and decreasing neutron number. The observed 80Y beta-decay fragmentation and log ft values have also been used to assign spin and parity of 4(-) and 1(-) to the parent ground state and the 228.5 keV isomeric state, respectively. [S0556-2813(99)01601-5]. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Maryland, Dept Chem, College Pk, MD 20742 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. RP Doring, J (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 50 TC 20 Z9 20 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 59 EP 70 DI 10.1103/PhysRevC.59.59 PG 12 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400009 ER PT J AU Tuve, C Albergo, S Boemi, D Caccia, Z Chen, CX Costa, S Crawford, HJ Cronqvist, M Engelage, J Greiner, L Guzik, TG Knott, CN Insolia, A Lindstrom, PJ Mitchell, JW Potenza, R Russo, GV Soutoul, A Testard, O Tricomi, A Tull, CE Waddington, CJ Webber, WR Wefel, JP AF Tuve, C Albergo, S Boemi, D Caccia, Z Chen, CX Costa, S Crawford, HJ Cronqvist, M Engelage, J Greiner, L Guzik, TG Knott, CN Insolia, A Lindstrom, PJ Mitchell, JW Potenza, R Russo, GV Soutoul, A Testard, O Tricomi, A Tull, CE Waddington, CJ Webber, WR Wefel, JP TI Neutron production in coincidence with fragments from the Ca-40+H reaction at E-lab=357A and 565A MeV SO PHYSICAL REVIEW C LA English DT Article ID PRODUCTION CROSS-SECTIONS; HEAVY-ION COLLISIONS; AU-AU COLLISIONS; NICKEL PROJECTILES; RELATIVISTIC NEON; ENERGY-DEPENDENCE; HYDROGEN; INTERMEDIATE; CRITICALITY; 0-DEGREES AB Neutron production, in coincidence with fragments emitted in the Ca-40+H reaction at E-lab=357A and 565A MeV, has been measured using a 3-module version of the multifunctional neutron spectrometer MUFFINS. The mean neutron multiplicities for neutrons detected in the angular range covered by MUFFINS (0 degrees - 3.2 degrees) have been estimated from the comparison between the neutron cross sections, in coincidence with the fragments, and the elemental cross sections. We have found evidence for a preequilibrium emission of prompt neutrons in superposition to a "slower" deexcitation of the equilibrated remnant by emission of nucleons and fragments, as already seen in inclusive rapidity distributions. The energy dependence of die inclusive neutron production cross sections, measured in a previous work, is here interpreted as due to the stronger neutron focusing in the forward direction at the higher energy. Comparison with a BNV+phase space coalescence model is discussed. [S0556-2813(99)01101-2]. C1 Univ Catania, I-95129 Catania, Italy. Ist Nazl Fis Nucl, I-95129 Catania, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Minnesota, Minneapolis, MN 55455 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. CENS, Serv Astrophys, F-91191 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Univ Catania, I-95129 Catania, Italy. RI Insolia, Antonio/M-3447-2015; TUVE', Cristina/P-3933-2015; OI Insolia, Antonio/0000-0002-9040-1566; TUVE', Cristina/0000-0003-0739-3153; Tricomi, Alessia Rita/0000-0002-5071-5501; Costa, Salvatore/0000-0001-9919-0569 NR 25 TC 5 Z9 5 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 233 EP 238 PG 6 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400027 ER PT J AU Boggild, H Boissevain, J Dodd, J Esumi, S Fabjan, CW Fields, DE Franz, A Hansen, KH Humanic, TJ Jacak, BV Kalechofsky, H Lee, YY Leltchouk, M Lorstad, B Maeda, N Miyabayashi, A Murray, M Nishimura, S Pandey, SU Piuz, F Polychronakos, V Potekhin, M Poulard, G Sakaguchi, A Sarabura, M Simon-Gillo, J Schmidt-Sorensen, J Sondheim, W Sugitate, T Sullivan, JP Sumi, Y van Hecke, H Willis, WJ Wolf, K AF Boggild, H Boissevain, J Dodd, J Esumi, S Fabjan, CW Fields, DE Franz, A Hansen, KH Humanic, TJ Jacak, BV Kalechofsky, H Lee, YY Leltchouk, M Lorstad, B Maeda, N Miyabayashi, A Murray, M Nishimura, S Pandey, SU Piuz, F Polychronakos, V Potekhin, M Poulard, G Sakaguchi, A Sarabura, M Simon-Gillo, J Schmidt-Sorensen, J Sondheim, W Sugitate, T Sullivan, JP Sumi, Y van Hecke, H Willis, WJ Wolf, K TI Charged kaon and pion production at midrapidity in proton-nucleus and sulphur-nucleus collisions SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-ION COLLISIONS; INTERSECTING STORAGE-RINGS; LARGE TRANSVERSE-MOMENTUM; QUARK-GLUON PLASMA; INCLUSIVE PRODUCTION; BARYON PRODUCTION; 200 GEV/C; HADRONS; DYNAMICS; SPECTRA AB The NA44 Collaboration has measured charged kaon and pion distributions at midrapidity in sulphur and proton collisions with nuclear targets at 200 and 450 GeV/c per nucleon, respectively. The inverse slopes of kaons, are larger than those of pions. The difference in the inverse slopes of pions, kaons, and protons, all measured in our spectrometer, increases with system size and is consistent with the buildup of collective flow for larger systems. The target dependence of both the yields and inverse slopes is stronger for the sulphur beam, suggesting the increased importance of secondary rescattering for SA reactions. The rapidity density dN/dy of both K+ and K- increases more rapidly with system size than for pi(+) in a similar rapidity region. This trend continues with increasing centrality, and according to RQMD, it is caused by secondary reactions between mesons and baryons. The K-/K+ ratio falls with increasing system size but more slowly than the (p) over bar/p ratio. The pi(-)/pi(+) ratio is close to unity for all systems. From pBe to SPb the K+/p ratio decreases while K-/(p) over bar increases and root((K+.K-)/(p.(p) over bar)) stays constant. These data suggest that as larger nuclei collide, the resulting system has a larger transverse expansion and baryon density and an increasing fraction of strange quarks. [S0556-2813(99)02201-3]. C1 Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Columbia Univ, New York, NY 10027 USA. Hiroshima Univ, Higashihiroshima 739, Japan. CERN, CH-1211 Geneva 23, Switzerland. Ohio State Univ, Columbus, OH 43210 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Univ Lund, S-22362 Lund, Sweden. Texas A&M Univ, College Stn, TX 77843 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Boggild, H (reprint author), Niels Bohr Inst, Blegdamsvej 17, DK-2100 Copenhagen, Denmark. NR 30 TC 25 Z9 25 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 328 EP 335 DI 10.1103/PhysRevC.59.328 PG 8 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400037 ER PT J AU Htun, MM Madey, R Zhang, WM Elaasar, M Keane, D Anderson, BD Baldwin, AR Jiang, J Scott, A Shao, Y Watson, JW Frankel, K Heilbronn, L Krebs, G McMahan, MA Rathbun, W Schambach, J Westfall, GD Yennello, S Gale, C Zhang, J AF Htun, MM Madey, R Zhang, WM Elaasar, M Keane, D Anderson, BD Baldwin, AR Jiang, J Scott, A Shao, Y Watson, JW Frankel, K Heilbronn, L Krebs, G McMahan, MA Rathbun, W Schambach, J Westfall, GD Yennello, S Gale, C Zhang, J TI Neutrons from multiplicity-selected La-La and Nb-Nb collisions at 400A MeV and La-La collisions at 250A MeV SO PHYSICAL REVIEW C LA English DT Article ID HEAVY-ION COLLISIONS; AU-AU COLLISIONS; RELATIVISTIC NUCLEAR COLLISIONS; TRANSVERSE-MOMENTUM ANALYSIS; COLLECTIVE FLOW; PROJECTILE ENERGY; EQUATION; STATE; MATTER; SCINTILLATORS AB Triple-differential cross sections for neutrons from high-multiplicity La-La collisions at 250 and 400 MeV per nucleon and Nb-Nb collisions at 400 MeV per nucleon were measured at several polar angles as a function of the azimuthal angle with respect to the reaction plane of the collision. The reaction plane was determined by a transverse-velocity method with the capability of identifying charged-particles with Z=1, Z=2, and Z>2. The flow of neutrons was extracted From the slope at mid-rapidity of the curve of the average in-plane momentum vs the center-of-mass rapidity. The squeeze-out of the participant neutrons was observed in a direction normal to the reaction plane in the normalized momentum coordinates in the center-of-mass system. Experimental results of the neutron squeeze-out were compared with BUU calculations. The polar-angle dependence of the maximum azimuthal anisotropy ratio r(theta) was found to be insensitive to the mass of the colliding nuclei and the beam energy. Comparison of the observed polar-angle dependence of the maximum azimuthal anisotropy ratio r(theta) with BUU calculations for free neutrons revealed that r(theta) is insensitive also to the incompressibility modulus in the nuclear equation of state. [S0556-2813(99)03701-2]. C1 Kent State Univ, Kent, OH 44242 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Michigan State Univ, E Lansing, MI USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. RP Htun, MM (reprint author), CyberAccess Inc, Valley View, OH 44125 USA. RI Heilbronn, Lawrence/J-6998-2013; Yennello, Sherry/B-5803-2015 OI Heilbronn, Lawrence/0000-0002-8226-1057; Yennello, Sherry/0000-0003-3963-5217 NR 36 TC 7 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 336 EP 347 DI 10.1103/PhysRevC.59.336 PG 12 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400038 ER PT J AU Liu, H Panitkin, S Xu, N AF Liu, H Panitkin, S Xu, N TI Event anisotropy in high energy nucleus-nucleus collisions SO PHYSICAL REVIEW C LA English DT Article ID FLOW; EXPANSION; SIGNATURE AB The predictions of event anisotropy parameters from transport model RQMD are compared with the recent experimental measurements for 158A GeV Pb+Pb collisions. Using the same model, we study the time evolution of event anisotropy at 2A GeV and 158A GeV for several colliding systems. For the first time, both momentum and configuration space information are studied using the Fourier analysis of the azimuthal angular distribution. We find that, in the model, the combination of the size of the colliding system and nuclear passing time plays a dominant role in determining the behavior of the anisotropy parameters. [S0556-2813(98)05412-0]. C1 Kent State Univ, Kent, OH 44242 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Liu, H (reprint author), Kent State Univ, Kent, OH 44242 USA. NR 25 TC 34 Z9 35 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 348 EP 353 DI 10.1103/PhysRevC.59.348 PG 6 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400039 ER PT J AU Dumitru, A Rischke, DH AF Dumitru, A Rischke, DH TI Collective dynamics in highly relativistic heavy-ion collisions SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; QUARK-GLUON PLASMA; TRANSVERSE FLOW; INITIAL CONDITIONS; PHOTON PRODUCTION; FREEZE-OUT; HYDRODYNAMICAL DESCRIPTION; PARTICLE-EMISSION; AU+AU COLLISIONS; MIXED-PHASE AB Hydrodynamics with cylindrical symmetry in transverse direction and longitudinal scaling how is employed to calculate the transverse momentum spectra of various hadrons and clusters (e.g., pi, K, N, Phi, Lambda, d, He) in central heavy-ion collisions at CERN-SPS and BNL-RHIC energies up to p(T)=4 GeV. We discuss the sensitivity of these spectra with respect to the initial transverse density profile as well as to the choice of "freeze-out" hypersurface. For root s = 18A GeV (SPS energy) and p(T)<2 GeV, overall good agreement of the p(T) distributions with data is found when freeze-out occurs along the T = 130 MeV isotherm. Even high-p(T) neutral pion data can be described for a particular choice of the initial transverse density profile. It is shown that the average transverse velocity [v(T)] of heavy hadrons and hadronic clusters is a good measure for the collective flow velocity. The latter is found to be rather similar for SPS and RHIC energies, due to the "stall" of the how within the long-lived mixed phase at RHIC. In the case of thermalization and hydrodynamical. expansion, the mean transverse momentum [PT] increases linearly with the hadron mass. In contrast, the string model FRITIOF 7.02, which does not account for rescattering of secondary hadrons, predicts a strong dependence of [p(T)] on the quark composition of the hadron. Because of the different sensitivity to hard processes, hadrons with charm (anti)quarks acquire significantly more transverse momentum than hadrons without c (or even without s) quarks. [S0556-2813(99)03901-1]. C1 Yale Univ, Dept Phys, New Haven, CT 06520 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Dumitru, A (reprint author), Yale Univ, Dept Phys, POB 208124, New Haven, CT 06520 USA. NR 84 TC 55 Z9 55 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 354 EP 363 DI 10.1103/PhysRevC.59.354 PG 10 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400040 ER PT J AU Papazoglou, P Zschiesche, D Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W AF Papazoglou, P Zschiesche, D Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W TI Nuclei in a chiral SU(3) model SO PHYSICAL REVIEW C LA English DT Article ID MEAN-FIELD MODELS; SIGMA-OMEGA MODEL; FINITE NUCLEI; VECTOR-MESONS; BROKEN SCALE; MATTER; SYMMETRY; PHENOMENOLOGY; SYSTEMATICS; COLLISIONS AB Nuclei can be described satisfactorily in a nonlinear chiral SU(3) framework, even with standard potentials of the linear sigma model. The condensate value of the strange scalar meson is found to be important for the properties of nuclei even without adding hyperons. By neglecting terms which couple the strange to the nonstrange condensate one can reduce the model to a Walecka model structure embedded in SU(3). We discuss inherent problems with chiral SU(3) models regarding hyperon optical potentials. [S0556-2813(98)07712-7]. C1 Univ Frankfurt, Inst Theoret Phys, D-60054 Frankfurt, Germany. GSI Darmstadt, D-64220 Darmstadt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Papazoglou, P (reprint author), Univ Frankfurt, Inst Theoret Phys, Postfach 11 19 32, D-60054 Frankfurt, Germany. RI Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 55 TC 170 Z9 172 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 411 EP 427 DI 10.1103/PhysRevC.59.411 PG 17 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400046 ER PT J AU Palarczyk, M Rapaport, J Hautala, C Prout, DL Goodman, CD van Heerden, IJ Sowinski, J Savopulos, G Yang, X Sages, HM Howes, R Carr, R Islam, M Sugarbaker, E Cooper, DC Lande, K Luther, B Taddeucci, TN AF Palarczyk, M Rapaport, J Hautala, C Prout, DL Goodman, CD van Heerden, IJ Sowinski, J Savopulos, G Yang, X Sages, HM Howes, R Carr, R Islam, M Sugarbaker, E Cooper, DC Lande, K Luther, B Taddeucci, TN TI Measurement of Gamow-Teller strength for I-127 as a solar neutrino detector SO PHYSICAL REVIEW C LA English DT Article ID CROSS-SECTIONS; P,N REACTION; SCATTERING; ENERGIES AB Gamow-Teller transition strengths obtained in the I-127(p,n)Xe-127 reaction studied at 94, 159, and 197 MeV incident proton energies are presented, and used to evaluate the efficiency of I-127 as a solar neutrino detector. Excitation of the J(pi) = (3/2)(+) first excited state at E-x = 0.125 MeV in Xe-127, sensitive to Be-7 solar neutrinos, is evaluated. The sum of Gamow-Teller strength up to particle emission threshold and up to 20 MeV excitation energy are also reported. This paper also provides a new measurement of the Coulomb displacement energy Delta E-c, the excitation energy of the isobaric analog state, and the centroid of the Gamow-Teller resonance in Xe-127. [S0556-2813(99)02101-9]. C1 Ohio Univ, Athens, OH 45701 USA. Kent State Univ, Dept Phys, Kent, OH 44242 USA. Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. Ball State Univ, Muncie, IN 47306 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Penn, Philadelphia, PA 19104 USA. Concordia Coll, Moorhead, MN 56562 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. Univ Western Cape, ZA-7535 Bellville, South Africa. RP Palarczyk, M (reprint author), Ohio Univ, Athens, OH 45701 USA. NR 28 TC 10 Z9 10 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP 500 EP 509 DI 10.1103/PhysRevC.59.500 PG 10 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400053 ER PT J AU Schlei, BR Strottman, D AF Schlei, BR Strottman, D TI Predictions for root s=200A GeV Au+Au collisions from relativistic hydrodynamics SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; HEAVY-ION REACTIONS; PARTICLE-PRODUCTION; PARTON AB The relativistic hydrodynamical model HYLANIDER-C is used to give estimates for single inclusive particle momentum spectra in root s=200 GeV/nucleon Au+Au collisions that will be investigated experimentally in the near future. The predictions are based on initial conditions that the initial fireball has a longitudinal extension of 1.6 fm and an initial energy density of 30.8 GeV/fm(3) as obtained from a cascade model. For the collision energy considered here, different stopping scenarios are explored for the first time. Our calculations give particle yields of the order of 10000 to 20000 charged particles per event. [S0556-2813(99)50401-9]. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, DDT, DO, Los Alamos, NM 87545 USA. RP Schlei, BR (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, P-25, Los Alamos, NM 87545 USA. EM schlei@LANL.gov; dds@LANL.gov NR 23 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 1999 VL 59 IS 1 BP R9 EP R12 DI 10.1103/PhysRevC.59.R9 PG 4 WC Physics, Nuclear SC Physics GA 158JC UT WOS:000078111400003 ER PT J AU Abe, K Abe, K Abe, T Adam, I Akagi, T Allen, NJ Arodzero, A Ash, WW Aston, D Baird, KG Baltay, C Band, HR Barakat, MB Bardon, O Barklow, TL Bauer, JM Bellodi, G Ben-David, R Benvenuti, AC Bilei, GM Bisello, D Blaylock, G Bogart, JR Bolen, B Bower, GR Brau, JE Breidenbach, M Bugg, WM Burke, D Burnett, TH Burrows, PN Calcaterra, A Caldwell, DO Calloway, D Camanzi, B Carpinelli, H Cassell, R Castaldi, R Castro, A Cavalli-Sforza, M Chou, A Church, E Cohn, HO Coller, JA Convery, MR Cook, V Cotton, R Cowan, RF Coyne, DG Crawford, G Damerell, CJS Danielson, MN Daoudi, M de Groot, N Dell'Orso, R Dervan, PJ de Sangro, R Dima, M D'Oliveira, A Dong, DN Du, PYC Dubois, R Eisenstein, BI Eschenburg, V Etzion, E Fahey, S Falciai, D Fan, C Fernandez, JP Fero, MJ Flood, K Frey, R Gillman, T Gladding, G Gonzalez, S Hart, EL Harton, JL Hasan, A Hasuko, K Hedges, SJ Hertzbach, SS Hildreth, MD Huber, J Huffer, ME Hughes, EW Huynh, X Hwang, H Iwasaki, M Jackson, DJ Jacques, P Jaros, JA Jiang, ZY Johnson, AS Johnson, JR Johnson, RA Junk, T Kajikawa, R Kalelkar, M Kamyshkov, Y Kang, HJ Karliner, L Kawahara, H Kim, YD King, R King, ME Kofler, RR Krishna, NM Kroeger, RS Langston, M Lath, A Leith, DWG Lia, V Lin, CJS Liu, X Liu, MX Loreti, M Lu, A Lynch, HL Ma, J Mancinelli, G Manly, S Mantovani, G Markiewicz, TW Maruyama, T Masuda, H Mazzucato, E McKemey, AK Meadows, BT Menegatti, G Messner, R Mockett, PM Moffeit, KC Moore, TB Morii, M Muller, D Murzin, V Nagamine, T Narita, S Nauenberg, U Neal, H Nussbaum, M Oishi, N Onoprienko, D Osborne, LS Panvini, RS Park, H Park, CH Pavel, TJ Peruzzi, I Piccolo, M Piemontese, L Pieroni, E Pitts, KT Plano, RJ Prepost, R Prescott, CY Punkar, GD Quigley, J Ratcliff, BN Reeves, TW Reidy, J Reinertsen, PL Rensing, PE Rochester, LS Rowson, PC Russell, JJ Saxton, OH Schalk, T Schindler, RH Schumm, BA Schwiening, J Sen, S Serbo, VV Shaevitz, MH Shank, JT Shapiro, G Sherden, DJ Shmakov, KD Simopoulos, C Sinev, NB Smith, SR Smy, MB Snyder, JA Staengle, H Stahl, A Stamer, P Steiner, R Steiner, H Strauss, MG Su, D Suekane, F Sugiyama, A Suzuki, S Swartz, M Szumilo, A Takahashi, T Taylor, FE Thom, J Torrence, E Toumbas, NK Trandafir, AI Turk, JD Usher, T Vannini, C Va'vra, J Vella, E Venuti, JP Verdier, R Verdini, PG Wagner, SR Wagner, DL Waite, AP Walston, S Wang, J Ward, C Watts, SJ Weidemann, AW Weiss, ER Whitaker, JS White, SL Wickens, FJ Williams, B Williams, DC Williams, SH Willocq, S Wilson, RJ Wisniewski, WJ Wittlin, JL Woods, M Word, GB Wright, TR Wyss, J Yamamoto, RK Yamartino, JM Yang, X Yashima, J Yellin, SJ Young, CC Yuta, H Zapalac, G Zdarko, RW Zhou, J AF Abe, K Abe, K Abe, T Adam, I Akagi, T Allen, NJ Arodzero, A Ash, WW Aston, D Baird, KG Baltay, C Band, HR Barakat, MB Bardon, O Barklow, TL Bauer, JM Bellodi, G Ben-David, R Benvenuti, AC Bilei, GM Bisello, D Blaylock, G Bogart, JR Bolen, B Bower, GR Brau, JE Breidenbach, M Bugg, WM Burke, D Burnett, TH Burrows, PN Calcaterra, A Caldwell, DO Calloway, D Camanzi, B Carpinelli, H Cassell, R Castaldi, R Castro, A Cavalli-Sforza, M Chou, A Church, E Cohn, HO Coller, JA Convery, MR Cook, V Cotton, R Cowan, RF Coyne, DG Crawford, G Damerell, CJS Danielson, MN Daoudi, M de Groot, N Dell'Orso, R Dervan, PJ de Sangro, R Dima, M D'Oliveira, A Dong, DN Du, PYC Dubois, R Eisenstein, BI Eschenburg, V Etzion, E Fahey, S Falciai, D Fan, C Fernandez, JP Fero, MJ Flood, K Frey, R Gillman, T Gladding, G Gonzalez, S Hart, EL Harton, JL Hasan, A Hasuko, K Hedges, SJ Hertzbach, SS Hildreth, MD Huber, J Huffer, ME Hughes, EW Huynh, X Hwang, H Iwasaki, M Jackson, DJ Jacques, P Jaros, JA Jiang, ZY Johnson, AS Johnson, JR Johnson, RA Junk, T Kajikawa, R Kalelkar, M Kamyshkov, Y Kang, HJ Karliner, L Kawahara, H Kim, YD King, R King, ME Kofler, RR Krishna, NM Kroeger, RS Langston, M Lath, A Leith, DWG Lia, V Lin, CJS Liu, X Liu, MX Loreti, M Lu, A Lynch, HL Ma, J Mancinelli, G Manly, S Mantovani, G Markiewicz, TW Maruyama, T Masuda, H Mazzucato, E McKemey, AK Meadows, BT Menegatti, G Messner, R Mockett, PM Moffeit, KC Moore, TB Morii, M Muller, D Murzin, V Nagamine, T Narita, S Nauenberg, U Neal, H Nussbaum, M Oishi, N Onoprienko, D Osborne, LS Panvini, RS Park, H Park, CH Pavel, TJ Peruzzi, I Piccolo, M Piemontese, L Pieroni, E Pitts, KT Plano, RJ Prepost, R Prescott, CY Punkar, GD Quigley, J Ratcliff, BN Reeves, TW Reidy, J Reinertsen, PL Rensing, PE Rochester, LS Rowson, PC Russell, JJ Saxton, OH Schalk, T Schindler, RH Schumm, BA Schwiening, J Sen, S Serbo, VV Shaevitz, MH Shank, JT Shapiro, G Sherden, DJ Shmakov, KD Simopoulos, C Sinev, NB Smith, SR Smy, MB Snyder, JA Staengle, H Stahl, A Stamer, P Steiner, R Steiner, H Strauss, MG Su, D Suekane, F Sugiyama, A Suzuki, S Swartz, M Szumilo, A Takahashi, T Taylor, FE Thom, J Torrence, E Toumbas, NK Trandafir, AI Turk, JD Usher, T Vannini, C Va'vra, J Vella, E Venuti, JP Verdier, R Verdini, PG Wagner, SR Wagner, DL Waite, AP Walston, S Wang, J Ward, C Watts, SJ Weidemann, AW Weiss, ER Whitaker, JS White, SL Wickens, FJ Williams, B Williams, DC Williams, SH Willocq, S Wilson, RJ Wisniewski, WJ Wittlin, JL Woods, M Word, GB Wright, TR Wyss, J Yamamoto, RK Yamartino, JM Yang, X Yashima, J Yellin, SJ Young, CC Yuta, H Zapalac, G Zdarko, RW Zhou, J TI Improved test of the flavor independence of strong interactions SO PHYSICAL REVIEW D LA English DT Article ID LEADING ORDER QCD; Z(0) RESONANCE; QUARKS; RECONSTRUCTION; HADRONIZATION; ANNIHILATION; ALPHA(S); DETECTOR; DECAY; JETS AB We present an improved comparison of the strong coupling of the gluon to light (q(l) = u + d + s), c, and b quarks, determined from multijet rates in flavor-tagged samples of hadronic Z(0) decays recorded with the SLC Large Detector at the SLAC Linear Collider between 1993 and 1995. Flavor separation among primary q(l)(q) over bar(l), c (c) over bar, and b (b) over bar final states was made on the basis of the reconstructed mass of long-lived heavy-hadron decay vertices, yielding tags with high purity and low bias against greater than or equal to 3-jet final states. We find: alpha(s)(c)/alpha(s)(uds) = 1.036 +/- 0.043(stat)(-0.045)(+0.041)(syst)(-0.018)(+0.020)(theory) and alpha(s)(b)/alpha(s)(uds) = 1.004 +/- 0.018(stat)(-0.031)(+0.026)(syst)(-0.029)(+0.018)(theory). C1 Aomori Univ, Aomori 030, Japan. Adelphi Univ, Garden City, NY 11530 USA. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Boston Univ, Boston, MA 02215 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Columbia Univ, Nevis Labs, Irvington, NY 10533 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Ist Nazl Fis Nucl, Sez Ferrara, I-44100 Ferrara, Italy. Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Illinois, Urbana, IL 61801 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Phys, Berkeley, CA 94720 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ Mississippi, University, MS 38677 USA. MIT, Cambridge, MA 02139 USA. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow 119899, Russia. Nagoya Univ, Nagoya, Aichi 464, Japan. Univ Oregon, Dept Phys, Eugene, OR 97403 USA. Univ Oxford, Oxford OX1 3RH, England. Univ Padua, I-35100 Padua, Italy. Univ Perugia, Ist Nazl Fis Nucl, I-06100 Perugia, Italy. Ist Nazl Fis Nucl, Sez Pisa, I-56010 Pisa, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Rutgers State Univ, Serin Phys Lab, Piscataway, NJ 08855 USA. Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. Sogang Univ, Seoul, South Korea. Soongsil Univ, Seoul 156743, South Korea. Univ Tennessee, Knoxville, TN 37996 USA. Tohoku Univ, Bubble Chamber Lab, Sendai, Miyagi 980, Japan. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Vanderbilt Univ, Stevenson Ctr, Nashville, TN 37235 USA. Univ Washington, Seattle, WA 98105 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, Gibbs Lab, New Haven, CT 06520 USA. RP Abe, K (reprint author), Aomori Univ, 2-3-1 Kohata, Aomori 030, Japan. RI de Groot, Nicolo/A-2675-2009; Stahl, Achim/E-8846-2011; de Sangro, Riccardo/J-2901-2012; Cavalli-Sforza, Matteo/H-7102-2015; Frey, Raymond/E-2830-2016; Kamyshkov, Yuri/J-7999-2016; Calcaterra, Alessandro/P-5260-2015 OI Stahl, Achim/0000-0002-8369-7506; de Sangro, Riccardo/0000-0002-3808-5455; Frey, Raymond/0000-0003-0341-2636; Kamyshkov, Yuri/0000-0002-3789-7152; Calcaterra, Alessandro/0000-0003-2670-4826 NR 38 TC 24 Z9 24 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 012002 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300004 ER PT J AU Agashe, K Graesser, M AF Agashe, K Graesser, M TI Supersymmetry breaking and the supersymmetric flavor problem: An analysis of decoupling the first two generation scalars SO PHYSICAL REVIEW D LA English DT Article ID SOFTLY BROKEN SUPERSYMMETRY; CHANGING NEUTRAL CURRENTS; STANDARD MODEL; PARTICLE PHYSICS; ANOMALOUS U(1); NATURALNESS CONSTRAINTS; DIMENSIONAL REDUCTION; SYMMETRY-BREAKING; UPPER-BOUNDS; MASSES AB The supersymmetric contributions to the flavor changing neutral current processes may be suppressed by decoupling the scalers of the first and second generations. It is known, however, that the heavy scalars drive the top squark mass squareds negative through the two-loop renormalization group evolution. This tension is studied in detail. Two new items are included in this analysis: the effect of the top quark Yukawa coupling and the QCD corrections to the supersymmetric contributions to Delta m(K). Even with Cabibbo-like degeneracy between the squarks of the first two generations, these squarks must be heavier than similar to 40 TeV to suppress Delta m(K). This implies, in the case of a high scale of supersymmetry breaking, that the boundary value of the top squark mass has to be greater than similar to 7 TeV to keep the top squark mass squared positive at the weak scale. Low-energy supersymmetry breaking at a scale that is of the same order as the mass of the heavy scalars is also considered. In this case the finite parts of the two-loop diagrams are computed to estimate the contribution of the heavy scaler masses to the top squark mass squared. It is found that for Cabibbo-like mixing between the squarks, the top squark mass at the boundary needs to be larger than similar to 2 TeV. Thus, for both cases, the large boundary value of the top squark masses leads to an unnatural amount of fine tuning to obtain the comet Z mass. [S0556-2821(98)04023-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. EM ksagashe@lbl.gov; mlgraesser@lbl.gov NR 50 TC 46 Z9 46 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 015007 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300077 ER PT J AU Albuquerque, IFM Farrar, GR Kolb, EW AF Albuquerque, IFM Farrar, GR Kolb, EW TI Exotic massive hadrons and ultrahigh energy cosmic rays SO PHYSICAL REVIEW D LA English DT Article ID FLYS EYE DETECTOR AB We investigate the proposal that primary cosmic rays of energy above the Greisen-Zatsepin-Kuzmin cutoff are exotic massive strongly interacting particles (uhecrons). We study the properties of air showers produced by uhecrons and find that masses in excess of about 50 GeV are inconsistent with the highest energy event observed. We also estimate that with sufficient statistics a uhecron of mass as low as 10 GeV may be distinguished from a proton. C1 Univ Chicago, Enrico Fermi Inst, Dept Astron & Astrophys, Chicago, IL 60637 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. Fermilab Natl Accelerator Lab, NASA Fermilab Astropys Ctr, Batavia, IL 60510 USA. RP Univ Chicago, Enrico Fermi Inst, Dept Astron & Astrophys, Chicago, IL 60637 USA. EM ifreire@mafalda.uchicago.edu; farrar@farrar.rutgers.edu; rocky@rigoletto.fnal.gov RI Albuquerque, Ivone/H-4645-2012 OI Albuquerque, Ivone/0000-0001-7328-0136 NR 43 TC 60 Z9 60 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 015021 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300091 ER PT J AU Atwood, D Soni, A AF Atwood, D Soni, A TI Extracting information on CKM phases, electroweak penguin diagrams, and new physics from B -> VV decays SO PHYSICAL REVIEW D LA English DT Article ID B-DECAYS; ANGULAR-CORRELATIONS; ISOSPIN ANALYSIS; CP-VIOLATION; ASYMMETRIES AB We derive constraints for B --> V1V2 modes (V-1,V-2 = vector meson) that allow a model-independent quantitative assessment of the contributions from electroweak penguin diagrams and/or new physics. The interplay of direct CP with oscillation studies then may lead to the extraction of the angle alpha, using B --> K*omega(rho) and B --> rho omega(phi). Any reservation one may have can be explicitly verified in a model-independent way by assuming only isospin conservation. We also briefly mention how the method can be used to extract gamma via B-s decays: B-s --> K* rho, (K) over bar*K*. C1 Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Atwood, D (reprint author), Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. NR 22 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 013007 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300012 ER PT J AU Bardeen, W Duncan, A Eichten, E Thacker, H AF Bardeen, W Duncan, A Eichten, E Thacker, H TI Quenched chiral artifacts for Wilson-Dirac fermions SO PHYSICAL REVIEW D LA English DT Article ID TOPOLOGICAL CHARGE; LATTICE; SPECTRUM; QCD AB We examine artifacts associated with the chiral symmetry breaking induced through the use of Wilson-Dirac fermions in lattice Monte Carlo computations. For light quark masses, the conventional quenched theory cannot be defined using direct Monte Carlo methods due to the existence of nonintegrable poles in physical quantities. These poles are associated with the red eigenvalue spectrum of the Wilson-Dirac operator. We show how this singularity structure can be observed in the analysis of both QED in two dimensions and QCD in four dimensions. [S0556-2821(98)07323-8]. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 13 TC 15 Z9 15 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014507 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300065 ER PT J AU Baur, U Keller, S Wackeroth, D AF Baur, U Keller, S Wackeroth, D TI Electroweak radiative corrections to W boson production in hadronic collisions SO PHYSICAL REVIEW D LA English DT Article ID LEADING-LOGARITHM CALCULATION; DEEP-INELASTIC SCATTERING; P(P)OVER-BAR COLLISIONS; PARTON DISTRIBUTIONS; ROOT-S=1.8 TEV; PBARP COLLISIONS; CROSS-SECTIONS; MONTE-CARLO; DECAYS; MASS AB The O(alpha) electroweak radiative corrections to the process [GRAPHICS] are calculated. The O(alpha) corrections can be decomposed into separate gauge invariant contributions to the W boson production and decay processes. Factorizing the collinear singularity associated with initial state photon radiation into the parton distribution functions, we find that initial state corrections have a significantly smaller effect than final state radiative corrections. We study in detail the effect of electroweak radiative corrections on a number of interesting observables: the W transverse mass distribution, the W to Z transverse mass ratio, the charge asymmetry of leptons in W --> rho nu decays, as well as the W production cross section and the W to Z cross section ratio. We also investigate how experimental lepton identification requirements change the effect of the electroweak corrections. C1 SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. Fermi Natl Accelerator Lab, Theory Grp, Batavia, IL 60510 USA. Paul Scherrer Inst, Theory Grp F1, CH-5232 Villigen, Switzerland. RP Baur, U (reprint author), SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. NR 69 TC 96 Z9 96 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 013002 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300007 ER PT J AU Burakovsky, L Page, PR AF Burakovsky, L Page, PR TI Scalar glueball mixing and decay SO PHYSICAL REVIEW D LA English DT Article ID RELATIVISTIC QUARK-MODEL; WAVE-FUNCTIONS; LATTICE; MESONS; F(0)(1500) AB We provide the first explanation of the counter-intuitive scalar glueball couplings to pseudoscalar mesons found in lattice QCD and predict hitherto uncalculated decay modes. Significant a(1)pi and (pi pi)(S)(pi pi)(S) couplings are found. We demonstrate the equivalence of linear and quadratic mass matrices for glueball-quarkonium mixing. The equivalence of formalisms which deal with a glueball-quarkonium basis and only a quarkonium basis is demonstrated. We show that the f(0)(1500) is not the heaviest state arising from glueball-quarkonium mixing for a glueball mass consistent with lattice QCD. The masses and couplings of scalar mesons, as well as their valence content, are calculated. [S0556-2821(99)02401-7]. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, MS B283, Los Alamos, NM 87545 USA. EM BURAKOV@T5.LANL.GOV; PRP@T5.LANL.GOV RI Page, Philip/L-1885-2015 OI Page, Philip/0000-0002-2201-6703 NR 45 TC 35 Z9 35 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014022 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300041 ER PT J AU Czarnecki, A Melnikov, K AF Czarnecki, A Melnikov, K TI Two-loop QCD corrections to semileptonic b decays at an intermediate recoil SO PHYSICAL REVIEW D LA English DT Article ID CB-VERTICAL-BAR; B->C TRANSITIONS; ZERO RECOIL; RESUMMATION; WIDTHS AB We present complete O(alpha(s)(2)) corrections to the decay b --> clv(l) at the point where the invariant mass of the leptons root q(2) equals the c quark mass. We use this result, together with previously obtained corrections at the ends of the q(2) spectrum, to estimate the total width of the semileptonic b-->c decay with O(alpha(s)(2)) accuracy, essential for the \V-cb\ determination. [S0556-2821(99)06501-7]. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Karlsruhe, Inst Theoret Teilchenphys, D-76128 Karlsruhe, Germany. RP Czarnecki, A (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 19 TC 27 Z9 27 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014036 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300055 ER PT J AU Dobrescu, BA Simmons, EH AF Dobrescu, BA Simmons, EH TI Top-bottom splitting in technicolor with composite scalars SO PHYSICAL REVIEW D LA English DT Article ID ELECTROWEAK SYMMETRY-BREAKING; TOPCOLOR-ASSISTED TECHNICOLOR; EXTENDED TECHNICOLOR; STANDARD MODEL; QUARK MASS; PHYSICS; PARAMETERS; VIOLATION; HIGGS AB We present a model of dynamical electroweak symmetry breaking in which the splitting between the top and bottom quark masses arises naturally. The W and Z masses are produced by a minimal technicolor sector, the top quark mass is given by the exchange of a weak-doublet technicolored scalar, and the other quark and lepton masses are induced by the exchange of a weak-doublet technicolor-singlet scaler. We show that, in the presence of the latter scaler, the vacuum alignment is correct even in the case of SU(2) technicolor. The fit of this model to the electroweak data gives an acceptable agreement (chi(2) = 28, for 20 degrees of freedom). The mass hierarchy between the standard fermions other than top can also be explained in terms of the hierarchy of squared-masses of some additional scalars. We discuss various possibilities for the compositeness of the scalars introduced here. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM bdob@fnal.gov; simmons@bu.edu NR 43 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 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 015014 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300084 ER PT J AU Duncan, A Eichten, E Thacker, H AF Duncan, A Eichten, E Thacker, H TI Efficient algorithm for QCD with light dynamical quarks SO PHYSICAL REVIEW D LA English DT Article ID LATTICE QCD; CHIRAL LOGARITHMS; WILSON FERMIONS; DIRAC OPERATOR; GAUGE-THEORIES; FULL QCD; APPROXIMATION; EIGENVALUES; SPECTRUM AB A new approach to the inclusion of virtual quark effects in lattice QCD simulations is presented. Infrared modes which build in the chiral physics in the Light quark mass limit are included exactly and in a gauge invariant way. At fixed physical volume the number of relevant infrared modes does not increase as the continuum limit is approached. The acceptance of our procedure does not decrease substantially in the limit of small quark masses. Two alternative approaches are discussed for including systematically the remaining ultraviolet modes. In particular, we present evidence that these modes are accurately described by an effective action involving only small Wilson loops. [S0556-2821(98)02423-0]. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NR 24 TC 29 Z9 29 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014505 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300063 ER PT J AU Hiller, JR Brodsky, SJ AF Hiller, JR Brodsky, SJ TI Nonperturbative renormalization and the electron's anomalous moment in large-alpha QED SO PHYSICAL REVIEW D LA English DT Review ID LIGHT-CONE QUANTIZATION; MASSIVE SCHWINGER MODEL; SPONTANEOUS SYMMETRY-BREAKING; RELATIVISTIC BOUND-STATE; FRONT FIELD-THEORY; TAMM-DANCOFF APPROXIMATION; YANG-MILLS THEORY; (1+1)-DIMENSIONAL PHI(4) THEORY; DIMENSIONAL PHI-4 THEORY; TRANSVERSE ZERO MODES AB We study the physical electron in quantum electrodynamics expanded on the light-cone Fock space in order to address two problems. (1) the physics of the electron's anomalous magnetic moment a, in nonperturbative QED and (2) the practical problems of ultraviolet regularization and renormalization in truncated nonperturbative light-cone Hamiltonian theory. We present results for a, computed in a light-cone gauge Fock space truncated to include one bare electron and at most two photons, i.e., up to two photons in flight. The calculational scheme uses an invariant mass cutoff, discretized light-cone quantization (DLCQ), a Tamm-Dancoff truncation of the Fock space, and a photon mass regulator. We introduce new weighting methods which greatly improve convergence to the continuum within DLCQ. Nonperturbative renormalization of the coupling and electron mass are carried out, and a limit on the magnitude of the effective physical coupling strength is computed. A large renormalized coupling strength alpha(R)=0.1 is then used to make the nonperturbative effects in the electron anomalous moment from the one-electron, two-photon Fock state sector numerically detectable. [S0556-2821(99)00101-0]. C1 Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Hiller, JR (reprint author), Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. NR 275 TC 14 Z9 14 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 016006 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300098 ER PT J AU Jackson, JD AF Jackson, JD TI Electromagnetic form factor corrections to collisional energy loss of pions and protons, and spin correction for muons SO PHYSICAL REVIEW D LA English DT Article AB At very high energies, the collisional energy loss of hadrons passing through matter is reduced relative to that of a point particle because of their extended electromagnetic structures. For fermions, spin and magnetic moment effects work in the opposite direction. Analytic and numerical results are given for pions, muons, and protons. The reductions are small, but increase with energy. At 1 TeV, for example, the reduction is 2.7-3.4 % for pions and 1.4-1.9 % for protons, depending on the material. The influence of form factors on the so-called z(3) effect at high energies is also addressed. [S0556-2821(98)06623-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Jackson, JD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 11 TC 5 Z9 5 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 017301 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300100 ER PT J AU Kodaira, J Nasuno, T Parke, S AF Kodaira, J Nasuno, T Parke, S TI QCD corrections to spin correlations in top quark production at lepton colliders SO PHYSICAL REVIEW D LA English DT Article ID CP VIOLATION; PAIR PRODUCTION; ANGULAR-CORRELATIONS; FERMILAB TEVATRON; HADRON COLLIDERS; POLARIZATION; DECAY; COLLISIONS; COUPLINGS; SUPERCOLLIDERS AB Spin correlations, using a generic spin basis, are investigated to leading order in QCD for top quark production at lepton colliders. Even though these radiative corrections induce an anomalous gamma/Z magnetic moment for the top quarks and allow for single real gluon emission, their effects on the top quark spin orientation are very small. The final results are that the top quarks (or top antiquarks) are produced in an essentially unique spin configuration in polarized lepton collisions even after including the O(alpha(s)) QCD corrections. [S0556-2821(98)06823-4]. C1 Hiroshima Univ, Dept Phys, Higashihiroshima 7398526, Japan. Fermi Natl Accelerator Lab, Dept Theoret Phys, Batavia, IL 60510 USA. RP Kodaira, J (reprint author), Hiroshima Univ, Dept Phys, Higashihiroshima 7398526, Japan. NR 36 TC 28 Z9 28 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014023 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300042 ER PT J AU Lagae, JF Sinclair, DK AF Lagae, JF Sinclair, DK TI Improved staggered quark actions with reduced flavor symmetry violations for lattice QCD SO PHYSICAL REVIEW D LA English DT Article ID FERMIONS AB We introduce a new class of actions for staggered quarks in lattice QCD which significantly reduce flavor symmetry violations in the pion mass spectrum. An action introduced by the MILC Collaboration for the same purpose is seen to be a special case. We discuss how such actions arise from a systematic attempt to reduce flavor symmetry violations in the weak coupling limit. It is shown that for quenched lattice QCD at 6/g(2) = 5.7, representative actions of this class give a considerable reduction in flavor symmetry violation over the standard staggered action, and a significant reduction over what is achieved by the MILC action. [S0556-2821(98)00221-5]. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 25 TC 55 Z9 55 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014511 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300069 ER PT J AU Olness, FI Scalise, RJ Tung, WK AF Olness, FI Scalise, RJ Tung, WK TI Heavy quark hadroproduction in perturbative QCD SO PHYSICAL REVIEW D LA English DT Article ID DIFFERENTIAL CROSS-SECTION; CTEQ PARTON DISTRIBUTIONS; P(P)OVER-BAR COLLISIONS; HADRONIC COLLISIONS; CHARM PRODUCTION; NEUTRAL-CURRENT; ROOT-S=1.8 TEV; COLLIDER ENERGIES; LEPTOPRODUCTION; SCATTERING AB Existing calculations of heavy quark hadroproduction in perturbative QCD are either based on the conventional zero-mass perturbative QCD theory, valid for energy scales much higher than the quark mass, or on a next-to-lending order (NLO) fixed-flavor-number (FFN) scheme which is appropriate for energy scales comparable to the quark mass. We formulate this problem in the general mass variable-flavor-number scheme which incorporates initial (final) state heavy quark parton distribution (fragmentation) functions as well as exact mass dependence in the hard cross section. This formalism has the built-in feature of reducing to the FFN scheme near threshold and to the conventional zero-mass parton picture in the very high energy limit. Making use of existing calculations in the NLO FFN scheme, we obtain more complete results on bottom quark production in the general scheme to order alpha(s)(3) both for current accelerator energies and for CERN LHC. Modest improvement over the FFN results is observed in the reduced scale dependence of the cross section and in the increased magnitude of the cross section, in the direction of experimental measurement. It is shown that the general scheme represents a more efficient way of organizing the perturbation series, since the bulk of the large NLO (alpha(s)(3)) FFN contribution to the single heavy-quark inclusive cross section is already contained in the (resummed) order alpha(s)(2) "heavy flavor excitation" term in this scheme. Remaining limitations of the present calculation and possible improvements are discussed. [S0556-2821(98)01923-7]. C1 So Methodist Univ, Dept Phys, Dallas, TX 75275 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Michigan State Univ, Dept Phys Astron, E Lansing, MI 48824 USA. RP So Methodist Univ, Dept Phys, Dallas, TX 75275 USA. NR 45 TC 28 Z9 28 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014506 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300064 ER PT J AU Pelaez, JR AF Pelaez, JR TI Hadronic gas chiral phase transition within generalized chiral perturbation theory SO PHYSICAL REVIEW D LA English DT Article ID FINITE-TEMPERATURE; QCD; CORRELATORS; MESONS AB We study the temperature evolution of the [(q) over bar q] condensate below the chiral phase transition. The hadronic gas is described using a virial expansion within generalized chiral perturbation theory. In such a way, we can implement both the large or small chiral condensate scenarios and analyze the condensate dependence on the values of the lightest quark masses. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM pelaez@slac.stanford.edu RI Pelaez, Jose/K-9767-2014 OI Pelaez, Jose/0000-0003-0737-4681 NR 33 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014002 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300021 ER PT J AU Qiu, JW Sterman, G AF Qiu, JW Sterman, G TI Single transverse-spin asymmetries in hadronic pion production SO PHYSICAL REVIEW D LA English DT Article ID DIRECT PHOTON PRODUCTION; LAMBDA-0 HYPERON POLARIZATION; IR-RENORMALON CONTRIBUTION; ODD PARTON DISTRIBUTIONS; POWER CORRECTIONS; INCLUSIVE PRODUCTION; FRAGMENTATION FUNCTIONS; QUANTUM CHROMODYNAMICS; HARD-SCATTERING; QCD AB We analyze single transverse-spin asymmetries for hadronic pion production at large transverse momenta using QCD factorization. In the large x(F) region, leading contributions to the asymmetries are naturally produced by twist-3 parton correlation functions that couple quark fields and gluon held strengths. With a simple model for these matrix elements, leading-order asymmetries calculated from QCD are consistent with data on pion production from Fermilab, and can be used to predict single-spin asymmetries at BNL RHIC. We argue that our perturbative calculation for the asymmetries is relevant to pion transverse momenta as low as a few GeV. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. SUNY Stony Brook, Inst Theoret Phys, Stony Brook, NY 11794 USA. RP Qiu, JW (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 66 TC 196 Z9 197 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014004 PG 29 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300023 ER PT J AU Radyushkin, AV AF Radyushkin, AV TI Double distributions and evolution equations SO PHYSICAL REVIEW D LA English DT Article ID VIRTUAL COMPTON-SCATTERING; LIGHT-RAY OPERATORS; WAVE-FUNCTIONS; PARTON DISTRIBUTIONS; QCD; ELECTROPRODUCTION; KERNELS; MESONS AB Applications of perturbative QCD to deeply virtual Compton scattering and hard exclusive meson electroproduction processes require a generalization of usual parton distributions for the case when long-distance information is accumulated in nonforward matrix elements [p'\O(0,z)\p] of quark and gluon light-cone operators. In our previous papers we used two types of nonperturbative functions parametrizing such matrix elements: double distributions F(x,y;t) and nonforward distribution functions F-zeta(X;t) Here we discuss in more detail the double distributions (DD's) and evolution equations which they satisfy. We propose simple models for F(x, y ; t = 0) DD's with correct spectral and symmetry properties which also satisfy the reduction relations connecting them to the usual parton densities f(x). In this way, we obtain self-consistent models for the zeta dependence of nonforward distributions. We show that, for small zeta, one can easily obtain nonforward distributions (in the X > zeta region) from the parton densities: F-zeta(X;t = 0) approximate to f(X - zeta/2). [S0556-2821(98)04223-4]. C1 Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. Jefferson Lab, Newport News, VA 23606 USA. Joint Inst Nucl Res Dubna, Theoret Phys Lab, Dubna, Russia. RP Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. NR 37 TC 156 Z9 156 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014030 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300049 ER PT J AU Rizzo, TG AF Rizzo, TG TI Gauge kinetic mixing and leptophobic Z ' in E-6 and SO(10) SO PHYSICAL REVIEW D LA English DT Article ID PRECISION ELECTROWEAK EXPERIMENTS; LOW-ENERGY PHENOMENOLOGY; LEFT-RIGHT MODEL; FUTURE COLLIDERS; GLOBAL ANALYSIS; STANDARD MODEL; FLAVOR PHYSICS; STRING MODELS; HEAVY PHYSICS; BOSONS AB We examine the influence of gauge kinetic mixing on the couplings of a TeV scale Z' in both E-6 and SO(10) models. The strength of such mixing, which arises due to the existence of incomplete matter representations at low scale, can be described by a single parameter delta. The value of this parameter can significantly influence the ability of both hadron and lepton colliders to detect a Z' using conventional search techniques. In addition, delta not equal 0 also adds to the complexities involved in separating E-6 Z' models from those arising from alternative scenarios. Employing a reasonable set of assumptions we have determined the allowed range for this parameter within a wide class of models via an RGE analysis. In particular, given the requirements of standard model gauge coupling unification, anomaly freedom, and perturbativity up to the GUT scale, we demonstrate that the necessary condition for exact leptophobia in eta type E-6 models, delta = -1/3, is impossible to achieve in this scenario. Furthermore we show that the allowed range for Sis rather restricted for arbitrary values of the mixing between the U(1)(chi) and U(1)(psi) type couplings. The SO(10) Z' model chi is discussed as a separate case since it requires special attention. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Rizzo, TG (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 65 TC 57 Z9 57 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 015020 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300090 ER PT J AU Swanson, ES Szczepaniak, AP AF Swanson, ES Szczepaniak, AP TI Heavy hybrids with constituent gluons SO PHYSICAL REVIEW D LA English DT Article ID FLUX-TUBE MODEL; EXOTIC MESON; HADRONS; GEV/C; GLUEBALLS; LATTICE; STATES; QUARKS AB Hybrid meson energies are calculated in the static quark limit with the dynamical quark model (DQM). Ln the DQM, transverse gluons are represented as effective constituents with a dynamically generated mass. Hybrid masses are determined within the Tamm-Dancoff approximation for the resulting relativistic Salpeter equation. Although the general features of the adiabatic potential surfaces correspond with lattice data, the results disagree on level orderings. Similar problems appear to exist in all constituent glue models of hybrids. We conclude that constituent gluons do not accurately represent soft gluonic degrees of freedom. The steps necessary to correct this deficiency are discussed. [S0556-2821 (99)05501-0]. C1 N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Jefferson Lab, Newport News, VA 23606 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Indiana Univ, Ctr Nucl Theory, Bloomington, IN 47405 USA. RP Swanson, ES (reprint author), N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. NR 30 TC 37 Z9 37 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 014035 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300054 ER PT J AU Teige, S Brabson, BB Crittenden, RR Dzierba, AR Gunter, J Lindenbusch, R Rust, DR Scott, E Smith, PT Sulanke, T Chung, SU Hackenburg, RW Olchanski, C Strassburger, C Weygand, DP Willutzki, HJ Bar-Yam, Z Cummings, JP Dowd, JP Eugenio, PM Hayek, M Kern, W King, E Shenhav, N Bodyagin, VA Demianov, AI Kodolova, OL Korotkikh, VL Kostin, MA Ostrovidov, AI Sarycheva, LI Sinev, NB Vardanyan, IN Yershov, AA Brown, DS Pedlar, TK Seth, KK Wise, J Zhao, D Adams, T Bishop, JM Cason, NM Ivanov, EI LoSecco, JM Manak, JJ Sanjari, AH Shephard, WD Stienike, DL Taegar, SA Thompson, DR Denisov, SP Dorofeev, V Kachaev, I Lipaev, VV Popov, AV Ryabchikov, DI Adams, GS Kuhn, J Napolitano, J Nozar, M Smith, JA White, DB Witkowski, M AF Teige, S Brabson, BB Crittenden, RR Dzierba, AR Gunter, J Lindenbusch, R Rust, DR Scott, E Smith, PT Sulanke, T Chung, SU Hackenburg, RW Olchanski, C Strassburger, C Weygand, DP Willutzki, HJ Bar-Yam, Z Cummings, JP Dowd, JP Eugenio, PM Hayek, M Kern, W King, E Shenhav, N Bodyagin, VA Demianov, AI Kodolova, OL Korotkikh, VL Kostin, MA Ostrovidov, AI Sarycheva, LI Sinev, NB Vardanyan, IN Yershov, AA Brown, DS Pedlar, TK Seth, KK Wise, J Zhao, D Adams, T Bishop, JM Cason, NM Ivanov, EI LoSecco, JM Manak, JJ Sanjari, AH Shephard, WD Stienike, DL Taegar, SA Thompson, DR Denisov, SP Dorofeev, V Kachaev, I Lipaev, VV Popov, AV Ryabchikov, DI Adams, GS Kuhn, J Napolitano, J Nozar, M Smith, JA White, DB Witkowski, M TI Properties of the a(0)(980) meson SO PHYSICAL REVIEW D LA English DT Article ID COUPLED-CHANNEL ANALYSIS; DRIFT CHAMBER; SYSTEM; REST; ETA AB Events of the type pi(-) p --> n eta pi(+) pi(-) and pi(-) p --> n eta pi(0) at 18 GeV/c are analyzed. The mass and width of the neutral and charged a(0)(980) were determined. The neutral a(0) is found to have a mass of (0.991 +/- 0.0025) GeV/c(2) and a width of (0.069 +/- 0.011) GeV/c(2). A partial wave analysis technique yields (0.9983 +/- 0.0040) and (0.072 +/- 0.010) GeV/c(2) for the mass and width of the changed a(0). C1 Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Massachusetts, Dept Phys, N Dartmouth, MA 02747 USA. Moscow State Univ, Inst Nucl Phys, Moscow, Russia. Northwestern Univ, Dept Phys, Evanston, IL 60208 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Inst High Energy Phys, Protvino, Russia. Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. RP Teige, S (reprint author), Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. RI Demianov, Andrei/E-4565-2012; Vardanyan, Irina/K-7981-2012 NR 31 TC 34 Z9 34 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 1 PY 1999 VL 59 IS 1 AR 012001 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 155VP UT WOS:000077967300003 ER PT J AU Ben-Naim, E Krapivsky, PL AF Ben-Naim, E Krapivsky, PL TI Maxwell model of traffic flows SO PHYSICAL REVIEW E LA English DT Article ID PHASE-TRANSITIONS; RANDOM RATES; EQUATIONS; KINETICS AB We investigate traffic flows using the kinetic Boltzmann equations with a Maxwell collision integral. This approach allows analytical determination of the transient behavior and the size distributions. The relaxation of the car and cluster velocity distributions towards steady state is characterized by a wide range of velocity-dependent relaxation scales, R-1/2< tau(upsilon)(z) = const, plus a perturbation (delta F-b) which evolves nonlinearly in the zero-order and perturbed field configurations. To illustrate the application of the technique to axisymmetric, matched-beam propagation, nonlinear delta F-simulation results are presented for the case where F-b(0) corresponds to a thermal equilibrium distribution, and the oscillatory component of the coupling coefficient, delta kappa(z)(s) = kappa(z)(s) - <(kappa)over bar>(z), turns on adiabatically over many periods S of the focusing lattice. For adiabatic turn-on of delta kappa(z)(s) over 20-100 lattice periods, the amplitude of the mismatch oscillation is reduced by more than one order of magnitude compared to the case where the field oscillation is turned on suddenly. Quiescent, matched-beam propagation at high beam intensities is demonstrated over several hundred lattice periods. (C) 1999 American Institute of Physics. [S1070-664(99)02401-5]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Stoltz, PH (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 44 TC 30 Z9 29 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 1999 VL 6 IS 1 BP 298 EP 315 DI 10.1063/1.873284 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 152TD UT WOS:000077792100034 ER PT J AU Brown, KL AF Brown, KL TI Edward Leonard Ginzton - Obituary SO PHYSICS TODAY LA English DT Biographical-Item C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Brown, KL (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD JAN PY 1999 VL 52 IS 1 BP 80 EP 82 DI 10.1063/1.882577 PG 3 WC Physics, Multidisciplinary SC Physics GA 154BA UT WOS:000077867100017 ER PT J AU Laxton, NF Balogh, A Cowley, SWH Dunlop, MW Hynds, RJ McComas, DJ Phillips, JL AF Laxton, NF Balogh, A Cowley, SWH Dunlop, MW Hynds, RJ McComas, DJ Phillips, JL TI Ulysses observations of field-perpendicular plasma flows in the Jovian magnetosphere: comparison of ExB velocity vectors derived from energetic ion and thermal electron data SO PLANETARY AND SPACE SCIENCE LA English DT Article ID HOT IONS; ANISOTROPY; JUPITER; MAGNETODISC; COROTATION; DEPARTURE; PROTONS; TORUS; MODEL AB The ExB velocity vectors which correspond to the field-perpendicular flow of the low-energy plasma have been independently derived for the Ulysses flyby of Jupiter using energetic ion and thermal electron data. In this paper these measurements are compared. It is shown that reasonable quantitative agreement exists during the prenoon inbound pass, though with some significant differences. Both data sets indicate the presence of slow field-perpendicular flows in the dayside outer magnetosphere (similar to 80-110 R-J), which are directed azimuthally opposite to corotation with the planet and radially inwards, with magnitudes of similar to 100 km s(-1) in each component. Any variations in this flow during the outer magnetosphere traversal are not resolved within the similar to+/-100 km s(-1) uncertainties in the individual 35 min-averaged data. Similar flows, but of somewhat smaller magnitude, are also found in both data sets in the higher-latitude region of the inbound middle magnetosphere flanking the plasma sheet (similar to 45-70 R-J). It is inferred that these field lines map equatorially into the outer magnetosphere at larger distances. Flows within the middle magnetosphere plasma sheet in this region are on average in the sense of planetary rotation, but the average azimuthal velocity determined from the ATs data (similar to 20 km s(-1), essentially consistent with zero) is significantly smaller than that determined from the SWOOPS data (similar to 100 km s(-1)). A systematic effect thus seems to be present within the current sheet, possibly associated with additional (usually small) terms in the expression for the energetic ion anisotropy which have not been taken into account in the analysis procedure. Analysis of the inbound data overall, however, indicates no consistent velocity offset between these data sets to within a few tens of km s(-1), and a unit gradient between them within a factor of similar to 1.5. Due to the large uncertainties in individual similar to 35-min velocity values, however, and the possible current sheet effects mentioned above, the cross-correlation coefficient between the data sets is low, with an overall value of 0.23 for the principal azimuthal component observed in magnetospheric regions over a 4-day interval on the inbound pass. The probability of this degree of correlation appearing by chance, however, is only about one in 500. On the outbound pass, we find that the velocity estimates determined from the two data sets do not agree, even qualitatively. We believe that this is due to a complicated and anisotropic background in the electron data which we have been unable to fully remove. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Imperial Coll, Blackett Lab, London SW7 2BZ, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Cowley, SWH (reprint author), Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. EM swhcl@ion.le.ac.uk RI dunlop, malcolm/F-1347-2010 NR 31 TC 9 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD JAN-FEB PY 1999 VL 47 IS 1-2 BP 205 EP 224 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 179JT UT WOS:000079324100021 ER PT J AU BassiriRad, H Prior, SA Norby, RJ Rogers, HH AF BassiriRad, H Prior, SA Norby, RJ Rogers, HH TI A field method of determining NH4+ and NO3- uptake kinetics in intact roots: Effects of CO2 enrichment on trees and crop species SO PLANT AND SOIL LA English DT Article DE CO2 enrichment; field method; intact roots; NH4+; NO3-; trees; uptake kinetics ID SPRUCE PICEA-ABIES; ATMOSPHERIC CARBON-DIOXIDE; NITRATE UPTAKE; LOBLOLLY-PINE; MINERAL-NUTRITION; TRANSPORT ANALOG; NUTRIENT-UPTAKE; PONDEROSA PINE; ION ABSORPTION; GROWTH-RATE AB Models describing plant and ecosystem N cycles require an accurate assessment of root physiological uptake capacity for NH4+ and NO3- under field conditions. Traditionally, rates of ion uptake in field-grown plants are determined by using excised root segments incubated for a short period in an assay solution containing N either as a radioactive or stable isotope tracer (e.g., (ClO3)-Cl-36 as a NH4+ analogue, (CH3NH3)-C-14 as an NO3- analogue or (NH4+)-N-15 and (NO3-)-N-15). Although reliable, this method has several drawbacks. For example, in addition to radioactive safety issues, purchase and analysis of radioactive and stable isotopes is relatively expensive and can be a major limitation. More importantly, because excision effectively interrupts exchange of compounds between root and shoot (e.g., carbohydrate supply to root and N transport to shoot), the assay must be conducted quickly to avoid such complications. Here we present a novel field method for simultaneous measurements of NH4+ and NO3- uptake kinetics in intact root systems. The application of this method is demonstrated using two tree species; red maple (Acer rubrum) and sugar maple (Acer saccharum) and two crop species soybean (Glycine max) and sorghum (Sorghum bicolor). Plants were grown in open-top chambers at either ambient or elevated levels of atmospheric CO2 at two separate US national sites involved in CO2 research. Absolute values of net uptake rates and the kinetic parameters determined by our method were found to be in agreement with the literature reports. Roots of the crop species exhibited a greater uptake capacity for both N forms relative to tree species. Elevated CO2 did not significantly affect kinetics of N uptake in species tested except in red maple where it increased root uptake capacity, V-max, for NH4+. The application, reliability, advantages and disadvantages of the method are discussed in detail. C1 Univ Illinois, Dept Biol Sci, Chicago, IL 60607 USA. ARS, USDA, Natl Soil Dynam Lab, Auburn, AL 36831 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP BassiriRad, H (reprint author), Univ Illinois, Dept Biol Sci, Chicago, IL 60607 USA. RI Norby, Richard/C-1773-2012 OI Norby, Richard/0000-0002-0238-9828 NR 54 TC 30 Z9 31 U1 2 U2 20 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0032-079X J9 PLANT SOIL JI Plant Soil PY 1999 VL 217 IS 1-2 BP 195 EP 204 DI 10.1023/A:1004685317998 PG 10 WC Agronomy; Plant Sciences; Soil Science SC Agriculture; Plant Sciences GA 270JR UT WOS:000084532600018 ER PT S AU Affinito, JD Gross, ME Mounier, PA Shi, MK Graff, GL AF Affinito, JD Gross, ME Mounier, PA Shi, MK Graff, GL BE Lee, WW DAgostino, R Wertheimer, MR TI Ultra high rate, wide area, plasma polymerized films from high molecular weight/low vapor pressure liquid or liquid/solid suspension monomer precursors SO PLASMA DEPOSITION AND TREATMENT OF POLYMERS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Plasma Deposition and Treatment of Polymers, at the 1998 MRS Fall Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB A new process has been developed for the high rate vacuum deposition of solid films from high molecular weight/low vapor pressure liquid, or even liquid/solid suspension, monomer precursors. The gas resulting from the flash evaporation of a liquid monomer mixture, or from a suspension of insoluble solid particles in liquid monomer, is used as the support medium for a glow discharge in a Plasma Enhanced Chemical Vapor Deposition-like (PECVD) process. Due to the high molecular weight/low vapor pressure nature of the precursors, the plasma of the flash evaporated gas cryo-condenses at extremely high rate on substrates at ambient, and higher, temperatures. Upon condensation the liquified plasma immediately begins to polymerize to form a solid film due to the high concentration of radicals and ions contained in the liquid film. The process has been successfully implemented in a vacuum roll coating system in a roll-to-roll deposition process. Polymer films, Molecularly Doped Polymer (MDP) composite films of polymer containing light emitting organic molecules, and MDP composite films of polymer containing organic dye molecules have been deposited at thicknesses ranging from 0.1 microns to 24 microns at webs speeds as high as 96 linear meters per minute. This new deposition process will be discussed along with some properties of the films fabricated with this new process. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Affinito, JD (reprint author), Pacific NW Natl Lab, Battelle Blvd,MS KS-59, Richland, WA 99352 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-450-5 J9 MATER RES SOC SYMP P PY 1999 VL 544 BP 257 EP 268 PG 12 WC Materials Science, Multidisciplinary; Polymer Science SC Materials Science; Polymer Science GA BN69B UT WOS:000082590500036 ER PT J AU Pokrovsky, AS Fabritsiev, SA Barabash, VR Hamilton, ML Edwards, DJ Eiholzer, CR Garner, FA AF Pokrovsky, AS Fabritsiev, SA Barabash, VR Hamilton, ML Edwards, DJ Eiholzer, CR Garner, FA TI Irradiation-induced low-temperature creep of DS copper alloy SO PLASMA DEVICES AND OPERATIONS LA English DT Article DE copper alloys; neutron irradiation; in-pile creep AB The data are presented on in-pile creep of dispersion strengthened (DS) copper alloys MAGT 0.2 (Cu-0.2Al(2)O(3)). The experiment was performed in the SM-2 reactor in the Core position at T-irr similar to 80 degrees C and a dose of 5 dpa. Pipe samples loaded by inner helium pressure were irradiated for 41.2 days. Measurements of the pipe diameter after irradiation demonstrated that a low-temperature creep is observed in the DS alloy MAGT 0.2, the rate of which at a hoop stress of 117 MPa is as high as 2 x 10(-9) s(-1). The results of TEM investigations of the irradiated specimens structure are presented. The analysis of the obtained results and their comparison with the available data on creep of copper alloys in the unirradiated state allowed for the conclusion that irradiation increases essentially the creep of DS copper alloys. This effect is to be taken into account when estimating the life time of the ITER components and units. C1 DV Efremov Sci Res Inst, St Petersburg 189631, Russia. Sci Res Inst Atom Reactors, Dimitrovgrad 433510, Russia. ITER Joint Working Site, Garching, Germany. Pacific NW Lab, Richland, WA 99352 USA. RP Fabritsiev, SA (reprint author), DV Efremov Sci Res Inst, St Petersburg 189631, Russia. NR 8 TC 0 Z9 0 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1051-9998 J9 PLASMA DEVICES OPER JI Plasma Devices Oper. PY 1999 VL 7 IS 4 BP 313 EP 325 DI 10.1080/10519999908224475 PG 13 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA 247AY UT WOS:000083199500006 ER PT J AU May, MJ Fournier, KB Goetz, JA Terry, JL Pacella, D Finkenthal, M Marmar, ES Goldstein, WH AF May, MJ Fournier, KB Goetz, JA Terry, JL Pacella, D Finkenthal, M Marmar, ES Goldstein, WH TI Intrinsic molybdenum impurity density and radiative power losses with their scalings in ohmically and ICRF heated Alcator C-Mod and FTU tokamak plasmas SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID HEATING EXPERIMENTS; TRANSPORT; TEXTOR; ASDEX AB A new radiative cooling curve for molybdenum, determined from the Hebrew University, Jerusalem-Lawrence Livermore atomic code (HULLAC) has been used to estimate the radiative power losses from various ion cyclotron resonance frequency (ICRF) and ohmically heated Alcator C-Mod tokamak plasmas and ohmically heated Frascati tokamak upgrade (FTU) plasmas. This cooling curve has been found to accurately predict the radiative losses from molybdenum ions in plasma. Radiative losses from molybdenum computed by using the HULLAC cooling curve could typically account for greater than 60% of the total radiative losses as measured by bolometry in Alcator C-Mod tokamak plasmas. The molybdenum density was found to be as high as similar to 10(11) particles cm(-3) (n(Mo)/n(e) similar to 0.001) in ICRF heated plasmas. Plasmas after botonization of the plasma facing surfaces had the lowest molybdenum density and radiated power of all the plasmas examined; ICRF heated plasmas had the highest. The molybdenum density and radiative power losses were found to increase roughly linearly with input ICRF power during different heating schemes in plasmas with both I-I-mode and L-mode confinement. Although the molybdenum densities were found to decrease with increasing electron density, the radiative power losses did not change significantly for II types of plasmas studied in Alcator C-Mod and FTU: diverted plasmas heated with ICRF and both limited and diverted plasmas heated ohmically. C1 Johns Hopkins Univ, Dept Phys & Astron, Plasma Spect Grp, Baltimore, MD 21218 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. MIT, Ctr Plasma Fus, Cambridge, MA 02139 USA. EURATOM, ENEA, Ctr Ric Frascati, Rome, Italy. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP May, MJ (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Plasma Spect Grp, Baltimore, MD 21218 USA. NR 42 TC 18 Z9 18 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD JAN PY 1999 VL 41 IS 1 BP 45 EP 63 DI 10.1088/0741-3335/41/1/004 PG 19 WC Physics, Fluids & Plasmas SC Physics GA 164HA UT WOS:000078456300004 ER PT J AU Wong, KL AF Wong, KL TI A review of Alfven eigenmode observations in toroidal plasmas SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Review ID FUSION TEST REACTOR; DEUTERIUM-TRITIUM EXPERIMENTS; JOINT EUROPEAN TORUS; DIII-D TOKAMAK; SOFT-X-RAY; ALPHA-PARTICLES; NEUTRAL BEAM; ENERGETIC PARTICLES; MODE CONVERSION; TAE-MODES AB In toroidal magnetically confined plasmas, eigenmodes of Alfven waves can be destablized by energetic ions with velocities comparable to the Alfven velocity. With the advent of tokamak experiments in which populations of energetic ions can be introduced by neutral beam injection, radio frequency wave heating or by fusion reactions, major advances have been made in Alfven eigenmode research in the past 10 years. After introducing the basic concepts on the Alfven eigenmode instability, data on this subject from various toroidal devices are described, emphasizing the interplay between experiment and theory. Experimental results on mode identification, instability drive. mode damping and saturation, and energetic ion redistribution are compared with theory. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Wong, KL (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 188 TC 146 Z9 148 U1 1 U2 20 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD JAN PY 1999 VL 41 IS 1 BP R1 EP R56 DI 10.1088/0741-3335/41/1/001 PG 56 WC Physics, Fluids & Plasmas SC Physics GA 164HA UT WOS:000078456300001 ER PT S AU Jellison, GE Modine, FA Chen, C AF Jellison, GE Modine, FA Chen, C BE Goldstein, DH Chenault, DB TI Calibration procedures for a two-modulator generalized ellipsometer SO POLARIZATION: MEASUREMENT, ANALYSIS, AND REMOTE SENSING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Polarization - Measurement, Analysis, and Remote Sensing II CY JUL 19-21, 1999 CL DENVER, CO SP SPIE DE ellipsometry; generalized ellipsometry; uniaxial materials; cross polarization; photoelastic modulator ID OPTICAL FUNCTIONS AB A Two-Modulator Generalized Elipsometer (2-MGE) has been extremely useful in characterizing optical properties of uniaxial bulk materials, thin films and diffraction gratings. The instrument consists of two polarizer-photoelastic modulator pairs, one operating as the polarization state generator and the other as the polarization stare detector. Each photoelastic modulator operates at a different resonant frequency (such as 50 kHz and 60 kHz), making it possible to measure eight elements of the reduced sample Mueller matrix simultaneously. In certain configurations, light reflection from non-depolarizing anisotropic samples can be completely characterized by a single measurement, and the entire reduced Jones matrix can be determined, including the cross polarization coefficients. The calibration of the instrument involves the measurement of the azimuthal angle of the polarizer with respect to the modulator, the modulation amplitude, and the modulator strain for each polarizer photoelastic modulator pair, where the last two are functions of wavelengths. In addition, it is essential to calibrate the azimuthal angles of the polarization state generator and the polarization state detector with respect to the plane of incidence in the ellipsometry configuration that is used in the measurements. Because two modulators operating at different frequencies are used, these calibrations are actually easier and more accurate than for one modulator ellipsometers. In this paper, we will discuss these calibrations and the resultant accuracy limitations of the 2-MGE. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Jellison, GE (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 3 Z9 3 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3240-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3754 BP 150 EP 160 PG 11 WC Instruments & Instrumentation; Remote Sensing; Optics SC Instruments & Instrumentation; Remote Sensing; Optics GA BP12A UT WOS:000084180100017 ER PT S AU Westmacott, KH Hinderberger, S Radetic, T Dahmen, U AF Westmacott, KH Hinderberger, S Radetic, T Dahmen, U BE Laughlin, DE Rodbell, KP Thomas, O Zhang, B TI PVD growth of FCC metal films on single crystal Si and Ge substrates SO POLYCRYSTALLINE METAL AND MAGNETIC THIN FILMS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium L on Polycrystalline Metal and Magnetic Thin Films CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP IBM T J Watson Res Ctr, MMC Technol ID ATOMIC-STRUCTURE; GRAIN-BOUNDARY; INTERFACE; HETEROEPITAXY; BICRYSTALS; ALUMINUM; SILICON AB Epitaxial films of the fee metals Al, Au, Ag and Ni were grown by physical vapor deposition on Si and Ge (111), (110) and (100) substrates at different deposition temperatures. The epitaxial relationships and morphological features of these films were characterized by transmission electron microscopy and diffraction in plan view and cross section. Ag formed single crystal films on all substrates at all temperatures. Au and Al could be grown as bicrystals, and under some conditions, Al and Ni grew as tricrystal films. The morphological effects of diffusion at the metal/substrate interface are ascribed to diffusion induced grain boundary migration. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Westmacott, KH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 28 TC 6 Z9 6 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-469-6 J9 MATER RES SOC SYMP P PY 1999 VL 562 BP 93 EP 102 PG 10 WC Computer Science, Hardware & Architecture; Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films; Materials Science, Composites SC Computer Science; Materials Science; Metallurgy & Metallurgical Engineering GA BP30E UT WOS:000084623600014 ER PT J AU Lin, CH Zamzow, D Small, GJ Jankowiak, R AF Lin, CH Zamzow, D Small, GJ Jankowiak, R TI Time-dependent blue shift of the fluorescence origin band of benzo[a]pyrene (BP)-derived BP-6-N7Ade adducts in glasses SO POLYCYCLIC AROMATIC COMPOUNDS LA English DT Article DE benzo[a]pyrene; one-electron oxidation adduct; BP-6-N7Ade adduct; fluorescence spectroscopy; Stokes shift ID DNA ADDUCTS; MOUSE SKIN AB We report unusual spectroscopic properties of the benzo[a]pyrene (BP)-derived one-electron oxidation DNA adduct, BP-6-N7Ade, in glasses at low temperatures. Time-resolved fluorescence emission and fluorescence excitation spectra showed that the position of the origin bands shift to higher energies with longer delay lime of the observation window. A non-linear and time-dependent Stokes shift has been revealed. This effect has not been observed for any BP-derived diol-epoxide adduct. Such a blue-shift, in opposite direction to the shift expected from solvation dynamics, has not been previously reported. The experimental data are interpreted in terms of a distribution of conformers and a matrix-induced frequency dependent dipole moment change across the inhomogeneously broadened absorption band. C1 Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Lin, CH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1040-6638 J9 POLYCYCL AROMAT COMP JI Polycycl. Aromat. Compd. PY 1999 VL 14 BP 43 EP 52 DI 10.1080/10406639908019110 PG 10 WC Chemistry, Organic SC Chemistry GA 297HC UT WOS:000086076000006 ER PT J AU Barik, AK Paul, S Kar, SK Butcher, RJ Bryan, JC AF Barik, AK Paul, S Kar, SK Butcher, RJ Bryan, JC TI Synthesis and spectroscopic characterization of nickel(II) complexes with 5-methyl-3-formylpyrazole-N(4)methylthiosemicarbazone (HL4Me): X-ray crystallographic studies of [Ni(HL4Me)(2)](NO3)center dot(2)2H(2)O SO POLYHEDRON LA English DT Article DE Ni(II) complexes; methylformyl pyrazole methylthiosemicarbazone; X-ray structure; spectroscopic studies ID COPPER(II) COMPLEXES; DONOR LIGANDS; THIOSEMICARBAZONE; COBALT(II); CRYSTAL; ANTIFUNGAL; CHEMISTRY AB The coordination mode of the title ligand, HL4Me (synthesized and characterized by mass, IR and H-1 NMR spectral parameters) is reported by solid-state isolation and physicochemical identification of a few bis complexes of nickel(II) with different counterions. Magnetic and electronic spectral features classify the reported species, [Ni(HL4Me)(2)]X-2 . 2H(2)O, as six-coordinate, pseudo-octahedral with appreciable tetragonal distortion. Vibrational spectral data have indicated a neutral tridentate (NNS) function of HL4Me through the pyrazolyl (tertiary) ring nitrogen, azomethine nitrogen and thiocarbonyl sulphur. X-ray crystallographic studies of [Ni(HL4Me)(2)](NO3)(2) . 2H(2)O (triclinic, P (1) over bar) has unambiguously proved the distorted octahedral environment of the nickel(II) ion; the ligand molecules are trans coordinated to the central nickel(II) ion. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Coll Sci, Dept Chem, Calcutta 700009, W Bengal, India. Howard Univ, Dept Chem, Washington, DC 20059 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Kar, SK (reprint author), Univ Coll Sci, Dept Chem, 92 APC Rd, Calcutta 700009, W Bengal, India. EM skkar@cucc.ernet.in NR 33 TC 13 Z9 13 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-5387 J9 POLYHEDRON JI Polyhedron PY 1999 VL 18 IS 3-4 BP 571 EP 576 PG 6 WC Chemistry, Inorganic & Nuclear; Crystallography SC Chemistry; Crystallography GA 156ZQ UT WOS:000078033700034 ER PT J AU Clark, DL Gordon, JC Scott, BL Watkin, JG AF Clark, DL Gordon, JC Scott, BL Watkin, JG TI Synthesis and characterization of a mixed-ring bis-cyclopentadienyl derivative of neodymium. X-ray crystal structures of (eta-C5Me5)NdI2(py)(3) and (eta-C5Me5)(eta-C5H4SiMe3)NdI(py) SO POLYHEDRON LA English DT Article DE mixed-ring; neodymium; metallocene; iodide ID LEWIS BASE ADDUCTS; MOLECULAR-STRUCTURE; ORGANOMETALLIC COMPOUNDS; ASYMMETRIC CATALYSIS; METAL OXIDATION; COMPLEXES; LANTHANIDES; CHEMISTRY; METATHESIS; YTTERBIUM AB Reaction of neodymium metal with 1.5 equiv of elemental iodine in iso-propanol, followed by crystallization from THF, leads to isolation of NdI3(TKF)(x) (1). Compound 1 reacts with one equiv of KC5Me5 to produce the mono-pentamethylcyclopentadienyl derivative (eta-C5Me5)NdI2(THF)(3) (2) in moderate yield. Treatment of 2 with an excess of pyridine in toluene leads to displacement of the THF ligands and formation of the tris-pyridine adduct (eta-C5Me5)NdI2(py)(3) (3). Compound 3 reacts with one equiv of KC5H4SiMe3 to yield the mixed-ring complex (eta-C5Me5)(eta-C5H4SiMe3)NdI(py) (4). Single crystal X-ray diffraction studies have been performed on complexes 3 and 4. (eta-C5Me5)NdI2(py)(3) (3) adopts a pseudo-octahedral geometry in the solid state, with the cyclopentadienyl ligand occupying one coordination site, the three pyridine ligands in a mer-configuration, and the iodide ligands trans to one another. The Nd-I distance is 3.1603(5) Angstrom, while Nd-N bond lengths to the pyridine ligands are 2.631(4) and 2.678(6) Angstrom. The solid state structure of (eta-C5Me5)(eta-C5H4SiMe3)NdI(py) (4) features a typical bent metallocene Cp2MX2 geometry with Nd-I and Nd-N distances of 3.0664(4) and 2.555(4) Angstrom, respectively. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Watkin, JG (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, CST-18,Mail Stop J514, Los Alamos, NM 87545 USA. RI Clark, David/A-9729-2011; Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 49 TC 31 Z9 31 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-5387 J9 POLYHEDRON JI Polyhedron PY 1999 VL 18 IS 10 BP 1389 EP 1396 DI 10.1016/S0277-5387(98)00438-0 PG 8 WC Chemistry, Inorganic & Nuclear; Crystallography SC Chemistry; Crystallography GA 196TZ UT WOS:000080324800002 ER PT J AU Fukui, K Sumpter, BG Barnes, MD Noid, DW AF Fukui, K Sumpter, BG Barnes, MD Noid, DW TI Molecular dynamics simulation of polymer fine particles. Physical and mechanical properties SO POLYMER JOURNAL LA English DT Article DE molecular dynamics; polymer particles; melting point; compressive modulus; polyethylene ID POLYETHYLENE DEFORMATION; CRYSTALLINE POLYETHYLENE; FORCE-FIELD; CHAIN; SURFACE; COLLAPSE; DIFFUSION; TENSION; MODULUS AB Molecular dynamics simulations are used to study the atomistic details of nanometer scale polyethylene (PE) particles to gain insight into the properties and behavior of ultra fine polymer powders. From the nano-sized particles generated with up to 60000 atoms using an efficient MD method, structure and a variety of structural and physical characteristics were computed by averaging over sets of microstates at particular temperatures. The melting point, glass transition temperature, and heat capacity of the particles as a function of polymer chain length and particle size were obtained by monitoring the molecular volume and total energy. The results of our simulations predict an interesting reduction of the melting point and significantly smaller compressive modulus in comparison with the bulk system. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Fukui, K (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 57 TC 14 Z9 14 U1 1 U2 6 PU SOC POLYMER SCIENCE JAPAN PI TOKYO PA TSUKIJI DAISAN NAGAOKA BLDG, 2-4-2 TSUKIJI, CHUO-KU, TOKYO, 104, JAPAN SN 0032-3896 J9 POLYM J JI Polym. J. PY 1999 VL 31 IS 8 BP 664 EP 671 DI 10.1295/polymj.31.664 PG 8 WC Polymer Science SC Polymer Science GA 243DB UT WOS:000082980800006 ER PT J AU Daniels, EJ AF Daniels, EJ TI Advanced process research and development to enhance materials recycling SO POLYMER-PLASTICS TECHNOLOGY AND ENGINEERING LA English DT Article AB Innovative, cost-effective technologies that have a positive life-cycle environmental impact and yield marketable products are needed to meet the challenges of the recycling industry. Two polymeric materials-recovery technologies that are being developed at Argonne National Laboratory in cooperation with industrial partners are described in this article. C1 Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Daniels, EJ (reprint author), Argonne Natl Lab, Div Energy Syst, 9700 S Cass Ave,Bldg 362, Argonne, IL 60439 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0360-2559 J9 POLYM-PLAST TECHNOL JI Polym.-Plast. Technol. Eng. PY 1999 VL 38 IS 3 BP 569 EP 579 DI 10.1080/03602559909351600 PG 11 WC Polymer Science SC Polymer Science GA 210AE UT WOS:000081082300013 ER PT J AU Dowley, LJ Carnegie, SF Balandras-Chatot, C Ellisseche, D Gans, P Schober-Butin, B Wustman, R AF Dowley, LJ Carnegie, SF Balandras-Chatot, C Ellisseche, D Gans, P Schober-Butin, B Wustman, R TI Guidelines for evaluating disease resistance in potato cultivars. Foliage blight resistance (field test) Phytophthora infestans (Mont.) de Bary SO POTATO RESEARCH LA English DT Article AB To determine, by means of official tests, the resistance to foliage blight under field conditions of advanced clones and new potato cultivars which may be included on a National List or The Common Catalogue of Varieties of Agricultural Plant Species. C1 Oak Pk Res Ctr, Plant Pathol & Entomol Dept, Carlow, Ireland. Scottish Agr Sci Serv, Edinburgh EH12 8NJ, Midlothian, Scotland. Germicopa, F-29520 Chateauneuf du Faou, France. INRA, F-29260 Ploudaniel, France. NIAB, Cambridge CB3 0LE, England. BBA, Inst Pflanzenschutz, D-38104 Braunschweig, Germany. PAV, NL-8200 AK Lelystad, Netherlands. RP Dowley, LJ (reprint author), Oak Pk Res Ctr, Plant Pathol & Entomol Dept, Carlow, Ireland. NR 3 TC 6 Z9 6 U1 1 U2 1 PU EUROPEAN ASSN POTATO RES PI WAGENINGEN PA POSTBUS 20, 6700 WAGENINGEN, NETHERLANDS SN 0014-3065 J9 POTATO RES JI Potato Res. PY 1999 VL 42 IS 1 BP 107 EP 111 DI 10.1007/BF02358397 PG 5 WC Agronomy SC Agriculture GA 200AZ UT WOS:000080517700012 ER PT B AU Anderson, IE Terpstra, RL Ting, J Yu, C AF Anderson, IE Terpstra, RL Ting, J Yu, C BE Marquis, FDS TI Advances in gas atomization processing efficiency and control SO POWDER MATERIALS: CURRENT RESEARCH AND INDUSTRIAL PRACTICES LA English DT Proceedings Paper CT International Symposium on Powder Materials - Current Research and Industrial Practices at the 1999 TMS Fall Meeting CY OCT 31-NOV 04, 1999 CL CINCINNATI, OH SP TMS AB Many advanced technologies based on particulate materials demand the availability of fine powders. High pressure gas atomization (HPGA), a close coupled discrete jet atomization method, has proved to be one of the most effective methods of producing rapidly solidified fine metal and alloy powders with high yields less than 20 microns. Development of HPGA nozzles with discrete jets resembling convergent-divergent (C-D) rocket nozzle designs was conducted to increase atomization efficiency and uniformity and to reduce the gas supply pressure needed for peak performance, Efficient use of C-D jets with high total kinetic energy in an atomization nozzle required development of a physical model of the gas dynamics in the atomization zone. Another benefit has been the ability to operate in a nearly constant aspiration mode over an extremely wide atomization gas supply pressure range, potentially advantageous for control of powder size, coarser than the maximum refinement limit. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Anderson, IE (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 34 TC 2 Z9 2 U1 1 U2 3 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-456-9 PY 1999 BP 3 EP 17 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP03U UT WOS:000083949700001 ER PT B AU Anderson, ML Ting, J Anderson, IE AF Anderson, ML Ting, J Anderson, IE BE Marquis, FDS TI Benefits of gas atomization processing of metal hydrides SO POWDER MATERIALS: CURRENT RESEARCH AND INDUSTRIAL PRACTICES LA English DT Proceedings Paper CT International Symposium on Powder Materials - Current Research and Industrial Practices at the 1999 TMS Fall Meeting CY OCT 31-NOV 04, 1999 CL CINCINNATI, OH SP TMS ID ALLOYS AB Certain types of intermetallic compounds can reversibly absorb and desorb hydrogen by forming crystalline hydrides. These materials have found uses in nickel-metal hydride batteries and as a mechanism for the safe, solid storage of hydrogen, in devices such as cryocoolers. Traditionally, the processing method used to make powders of these materials is by chill casting and crushing the material. This can lead to some undesirable properties such as an inconsistent composition between particles induced by solidification segregation, angular powders that flow and pack poorly, and unwanted impurities from the crushing process. One process that can alleviate these problems is high pressure gas atomization (HPGA). By atomizing the material, spherical powders with consistent compositions can be created. Any phase segregation present in the particles is easily homogenized with a short (less than one hour) annealing step. Atomization also allows for improved post-powder production processing such as surface treatment, electrode consolidation, and heat exchanger bed filling due to the improved powder flow and apparent density. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Anderson, ML (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 12 TC 3 Z9 3 U1 2 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-456-9 PY 1999 BP 49 EP 58 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP03U UT WOS:000083949700004 ER PT B AU Staudhammer, EP AF Staudhammer, EP BE Marquis, FDS TI Fundamental temperature aspects in shock consolidation of metal powders SO POWDER MATERIALS: CURRENT RESEARCH AND INDUSTRIAL PRACTICES LA English DT Proceedings Paper CT International Symposium on Powder Materials - Current Research and Industrial Practices at the 1999 TMS Fall Meeting CY OCT 31-NOV 04, 1999 CL CINCINNATI, OH SP TMS AB Shock compaction/consolidation has been widely investigated but Little used in manufacturing processes. The potential arenas of application are numerous, however, for a number of reasons its employment is very limited. This is true in part, because the process is not well understood and has inherent in it many variables. At the present time, no general accepted theory is available to account for the process mechanics and threshold conditions including very rapid reaction kinetics. Of utmost concern in the use of shock energies for compaction and consolidation is the appropriate deposition of energy, which involves a very rapid and intense shock wave. This paper will describe the many variables as applied to powder consolidation. Many of these variables are interdependent parameters such as shock pressure, strain, strain rate, temperature, shock velocity powder size, powder distribution, powder morphology, etc. These variables must be assessed as an accumulative sum. Many descriptions of these variables and their effects have been previously presented in various forms for particular systems. However, a conceptual description in temperature-time space as applied to powders has been very useful in understanding many of the consolidation successes and failures. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Staudhammer, EP (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-456-9 PY 1999 BP 317 EP 325 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BP03U UT WOS:000083949700025 ER PT J AU Costello, R AF Costello, R TI Biomass Cofiring offers cleaner future for coal plants SO POWER ENGINEERING LA English DT Article C1 US DOE, Washington, DC 20545 USA. RP Costello, R (reprint author), US DOE, Washington, DC 20545 USA. NR 6 TC 5 Z9 5 U1 0 U2 1 PU PENNWELL PUBL CO ENERGY GROUP PI TULSA PA 1421 S SHERIDAN RD PO BOX 1260, TULSA, OK 74101 USA SN 0032-5961 J9 POWER ENG JI Power Eng. PD JAN PY 1999 VL 103 IS 1 BP 45 EP 48 PG 4 WC Energy & Fuels; Engineering, Multidisciplinary SC Energy & Fuels; Engineering GA 161PN UT WOS:000078297900017 ER PT S AU Xu, S Wang, HL Malko, A Kohlman, R Smilowitz, L Klimov, V McBranch, DW Nogues, JL Moreshead, W Hagan, D Yang, S Van Stryland, E AF Xu, S Wang, HL Malko, A Kohlman, R Smilowitz, L Klimov, V McBranch, DW Nogues, JL Moreshead, W Hagan, D Yang, S Van Stryland, E BE Lawson, CM TI Toward the development of solid-state optical limiting devices SO POWER-LIMITING MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Power-Limiting Materials and Devices CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE dye-doped glasses; optical limiting; phthalocyanines; femtosecond transient adsorption ID PHTHALOCYANINE; FEMTOSECOND; FULLERENES; ABSORPTION; MECHANISMS; DYNAMICS AB We present our recent advances toward the development of high-performance solid-state optical limiting devices using reverse saturable absorption (RSA) dyes doped into optical host materials. Femtosecond transient absorption spectroscopy was employed to determine both the spectral regions of strong RSA, and the singlet-triplet excited-state dynamics. The optical limiting in the visible spectrum in both metallo-phthalocyanines and metallo-porphyrms is due to a combination of singlet and triplet RSA. Optical limiting performance was studied for RSA dyes in dual tandem limiters (both in solution and solid-state). Our best results in the solid-state yielded an attenuation of 400x, and a damage threshold of up to several mJ at f/5 focusing. The optical limiting at f/5 is further enhanced, particularly in the solid-state, by self-defocusing thermal nonlinearities. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Xu, S (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. NR 14 TC 3 Z9 3 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3284-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3798 BP 76 EP 84 DI 10.1117/12.363865 PG 9 WC Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BN98F UT WOS:000083742600009 ER PT B AU Davis, PJ Piscotty, MA Blaedel, KL AF Davis, PJ Piscotty, MA Blaedel, KL BE McKeown, P TI Process diagnostics for precision grinding brittle materials in a production environment SO PRECISION ENGINEERING, NANOTECHNOLOGY, VOL 1, PROCEEDINGS LA English DT Proceedings Paper CT 1st International Conference and General Meeting of the European-Society-for-Precision-Engineering and Nanotechnology CY MAY 31-JUN 04, 1999 CL Bremen, GERMANY SP European Soc Precis Engn & Nanotechnol C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Davis, PJ (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-537, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SHAKER VERLAG GMBH PI AACHEN PA POSTFACH 1290, AACHEN, 52013, GERMANY BN 3-8265-6085-X PY 1999 BP 195 EP 198 PG 4 WC Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BAN63 UT WOS:000222984000047 ER PT B AU Piscotty, MA Davis, PJ Blaedel, KL AF Piscotty, MA Davis, PJ Blaedel, KL BE McKeown, P TI Precision grinding process development for brittle materials SO PRECISION ENGINEERING, NANOTECHNOLOGY, VOL 1, PROCEEDINGS LA English DT Proceedings Paper CT 1st International Conference and General Meeting of the European-Society-for-Precision-Engineering and Nanotechnology CY MAY 31-JUN 04, 1999 CL Bremen, GERMANY SP European Soc Precis Engn & Nanotechnol C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Piscotty, MA (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-537, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SHAKER VERLAG GMBH PI AACHEN PA POSTFACH 1290, AACHEN, 52013, GERMANY BN 3-8265-6085-X PY 1999 BP 412 EP 415 PG 4 WC Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BAN63 UT WOS:000222984000102 ER PT B AU Zimmermann, M Davis, PJ Krulewich, DA Carr, JW Haack, JK McClellan, MR AF Zimmermann, M Davis, PJ Krulewich, DA Carr, JW Haack, JK McClellan, MR BE McKeown, P TI A machining parameter study to select best conditions for SPDT of large single-crystal silicon optics SO PRECISION ENGINEERING, NANOTECHNOLOGY, VOL 1, PROCEEDINGS LA English DT Proceedings Paper CT 1st International Conference and General Meeting of the European-Society-for-Precision-Engineering and Nanotechnology CY MAY 31-JUN 04, 1999 CL Bremen, GERMANY SP European Soc Precis Engn & Nanotechnol C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Zimmermann, M (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SHAKER VERLAG GMBH PI AACHEN PA POSTFACH 1290, AACHEN, 52013, GERMANY BN 3-8265-6085-X PY 1999 BP 466 EP 469 PG 4 WC Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BAN63 UT WOS:000222984000116 ER PT B AU Carr, JW Fearon, E Summers, LJ Hutcheon, ID AF Carr, JW Fearon, E Summers, LJ Hutcheon, ID BE McKeown, P Corbett, J Bonis, M Sartori, S Kunzmann, H Weck, M Brinksmeier, E Preub, W TI Subsurface damage assessment with atomic force microscopy SO PRECISION ENGINEERING, NANOTECHNOLOGY, VOL. 2 LA English DT Proceedings Paper CT 1st International Conference and General Meeting of the European-Society-for-Precision-Engineering and Nanotechnology CY MAY 31-JUN 04, 1999 CL Bremen, GERMANY SP European Soc Precis Engn & Nanotechnol ID GLASS C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Carr, JW (reprint author), Lawrence Livermore Natl Lab, POB 808,L-537, Livermore, CA 94551 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SHAKER VERLAG GMBH PI AACHEN PA POSTFACH 1290, AACHEN, 52013, GERMANY PY 1999 BP 451 EP 454 PG 4 WC Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BAP16 UT WOS:000223103000110 ER PT B AU Krakowski, RA Bennett, L Bertel, E AF Krakowski, RA Bennett, L Bertel, E BE Kursunoglu, BN Mintz, SL Perlmutter, A TI Nuclear fission: For safe, globally sustainable, proliferation-resistant, and cost-effective energy SO PREPARING THE GROUND FOR RENEWAL OF NUCLEAR POWER LA English DT Proceedings Paper CT Conference on Preparing the Ground for Renewal of Nuclear Power CY OCT 22-23, 1998 CL PARIS, FRANCE SP Natl Sci Fdn, Alpha Omega Res Fdn AB To varying degrees, under varying priorities, and depending strongly on country/region, the advancement of nuclear energy must deal with four cardinal issues: waste, proliferation, cost, and safety. While solutions to these issues are usually offered within a techno-economic framework, the future of nuclear energy is being determined by these issues largely through a socio-cultural paradigm vis a vis dwindling public acceptance of this technology. After giving a general perspective of energy consumption in terms of minimal requirements, needs, and constraints, the status of and prospects for nuclear energy are reviewed. Key elements of the public acceptance issue are then described, along with pathways being suggested to improve acceptance of this technology. After outlining a range of technical approaches to the future of nuclear energy offering new directions that might improve public acceptance through addressing the four cardinal issues, the long-term and global impacts and trade-offs for nuclear energy as estimated from an energy-economics-environmental model are reported, with an emphasis being placed on how that future may be tied to present concerns over the growing use of fossil fuels and possible climatic impacts related thereto. C1 Univ Calif Los Alamos Natl Lab, Syst Engn & Integrat Grp, Technol & Safety Assessment Div, Los Alamos, NM 87545 USA. RP Krakowski, RA (reprint author), Univ Calif Los Alamos Natl Lab, Syst Engn & Integrat Grp, Technol & Safety Assessment Div, Mail Stop F607, Los Alamos, NM 87545 USA. NR 52 TC 1 Z9 1 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46202-8 PY 1999 BP 107 EP 144 PG 38 WC Environmental Sciences; Nuclear Science & Technology SC Environmental Sciences & Ecology; Nuclear Science & Technology GA BP44D UT WOS:000085157600011 ER PT B AU Krakowski, RA AF Krakowski, RA BE Kursunoglu, BN Mintz, SL Perlmutter, A TI Presentations of the international conference on preparing the ground for renewal of nuclear power SO PREPARING THE GROUND FOR RENEWAL OF NUCLEAR POWER LA English DT Proceedings Paper CT Conference on Preparing the Ground for Renewal of Nuclear Power CY OCT 22-23, 1998 CL PARIS, FRANCE SP Natl Sci Fdn, Alpha Omega Res Fdn C1 Univ Calif Los Alamos Natl Lab, Technol & Safety Assessment Div, Syst Engn & Integrat Grp, Los Alamos, NM 87545 USA. RP Krakowski, RA (reprint author), Univ Calif Los Alamos Natl Lab, Technol & Safety Assessment Div, Syst Engn & Integrat Grp, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46202-8 PY 1999 BP 167 EP 168 PG 2 WC Environmental Sciences; Nuclear Science & Technology SC Environmental Sciences & Ecology; Nuclear Science & Technology GA BP44D UT WOS:000085157600014 ER PT S AU Gupta, R AF Gupta, R BE Gupta, R Morel, A DeRafael, E David, F TI Introduction to lattice QCD SO PROBING THE STANDARD MODEL OF PARTICLE INTERACTIONS, PARTS I AND II SE LES HOUCHES SUMMER SCHOOL SESSION LA English DT Proceedings Paper CT Les Houches Session LXVIII on Probing the Standard Model of Particle Interactions CY JUL 28-SEP 05, 1997 CL LES HOUCHES, FRANCE SP Univ Joseph Fourier, Minist Educ Natl, Enseignement Superieur & Rech, CNRS, CEA, NATO, Div Sci, US Natl Sci Fdn, Int Sci Fdn ID CHIRAL PERTURBATION-THEORY; LIGHT-QUARK MASSES; TEMPERATURE CONFINEMENT TRANSITIONS; EUCLIDEAN GREENS FUNCTIONS; EFFECTIVE FIELD-THEORY; FIXED-POINT ACTIONS; SU(3) GAUGE-THEORY; YANG-MILLS THEORY; WILSON FERMIONS; STAGGERED FERMIONS C1 Los Alamos Natl Lab, Div Theoret, Grp T8, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, Grp T8, Mail Stop B-285, Los Alamos, NM 87545 USA. NR 255 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-8099 BN 0-444-50099-5 J9 LES HOUCH S PY 1999 VL 68 BP 83 EP 219 PG 137 WC Physics, Particles & Fields SC Physics GA BP62Z UT WOS:000085716700003 ER PT B AU Vittitoe, CN Eyer, HH Guillen, JLL AF Vittitoe, CN Eyer, HH Guillen, JLL GP IEST IEST TI Solar-driven background intensity variations in a focal plane array SO PROCEEDINGS OF THE 18TH AEROSPACE TESTING SEMINAR LA English DT Proceedings Paper CT 18th Aerospace Testing Seminar CY MAR 16-18, 1999 CL MANHATTAN BEACH, CA SP Inst Environm Sci & Technol, Aerosp Corp DE noise measurements; background intensity; focal plane array; mercury-cadmium-telluride AB Portions of a series of end-of-life tests are described for a Sandia National Laboratories-designed space-based sensor that utilizes a mercury-cadmium-telluride focal plane array. Variations in background intensity are consistent with the hypothesis that seasonal variations in solar position cause changes in the pattern of shadows falling across the compartment containing the optical elements, filter-band components, and focal plane array. When the sensor compartment is most fully illuminated by the sun, background intensities are large and their standard deviations tend to be large. During the winter season, when the compartment is most fully shadowed by surrounding structure, background intensities are small and standard deviations tend to be small. Details in the surrounding structure are speculated to produce transient shadows that complicate background intensities as a function of time or of sensor position in orbit. C1 Sandia Natl Labs, Monitoring Syst Ctr, Livermore, CA 94550 USA. RP Vittitoe, CN (reprint author), Sandia Natl Labs, Monitoring Syst Ctr, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INST ENVIRONMENTAL SCIENCES PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA BN 1-877862-56-8 PY 1999 BP 75 EP 81 PG 3 WC Engineering, Aerospace SC Engineering GA BQ54M UT WOS:000088718700007 ER PT B AU Palumbo, AV Zhou, JZ Phelps, TJ Kinsall, BL Zhang, CL Majer, EL Peterson, JE Griffin, WT Pfiffner, SM AF Palumbo, AV Zhou, JZ Phelps, TJ Kinsall, BL Zhang, CL Majer, EL Peterson, JE Griffin, WT Pfiffner, SM BE Uzochukwu, GA Reddy, GB TI Ecology and bioremediation: A staged approach to site characterization SO PROCEEDINGS OF THE 1998 NATIONAL CONFERENCE ON ENVIRONMENTAL REMEDIATION SCIENCE AND TECHNOLOGY LA English DT Proceedings Paper CT 1998 National Conference on Environmental Remediation Science and Technology CY SEP 08-10, 1998 CL GREENSBORO, NC ID SUBSURFACE AB A four-stage approach to microbial characterization of subsurface sediments for bioremediation and ecological studies is proposed. The necessity for the staged approach arises from the heterogeneity of these subsurface environments, the requirement for large numbers of samples, and the difficulty and expense of many of the most powerful molecular techniques. The four stages are 1) a preliminary survey using inexpensive techniques, 2) data analysis, 3) focused sampling using more powerful and expensive techniques, and finally, 4) where possible, the use of geophysical techniques to extend the characterization across the site. Experience using this approach at uncontaminated sites as well as contaminated sites has demonstrated the capability of the staged characterization to identify potential controlling factors and relate geophysical data to microbial communities. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Palumbo, AV (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Palumbo, Anthony/A-4764-2011; phelps, tommy/A-5244-2011 OI Palumbo, Anthony/0000-0002-1102-3975; NR 9 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-069-1 PY 1999 BP 195 EP 204 PG 10 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BN63R UT WOS:000082439400020 ER PT S AU Rubin, JB Davenhall, LB Taylor, CMV Sivils, LD Pierce, T Tiefert, K AF Rubin, JB Davenhall, LB Taylor, CMV Sivils, LD Pierce, T Tiefert, K GP IEEE IEEE TI Carbon dioxide-based supercritical fluids as IC manufacturing solvents SO PROCEEDINGS OF THE 1999 IEEE INTERNATIONAL SYMPOSIUM ON ELECTRONICS AND THE ENVIRONMENT, ISEE - 1999 SE IEEE International Symposium on Electronics and the Environment-ISEE LA English DT Proceedings Paper CT 7th IEEE International Symposium on Electronics and the Environment (ISEE) CY MAY 11-13, 1999 CL DANVERS, MA SP IEEE Comp Soc ID METAL; EXTRACTION; PARTS AB The production of integrated circuits (IC's) involves a number of discrete steps which utilize hazardous or regulated solvents and generate large waste streams. ES&H considerations associated with these chemicals have prompted a search for alternative,more environmentally benign solvent systems. An emerging technology for conventional solvent replacement is the use of supercritical fluids based on carbon dioxide (CO(2)) Research work, conducted at Los Alamos in conjunction with the Hewlett-Packard Company, has lead to the development of a CO(2)-based supercritical fluid treatment system for the stripping of hard-baked photoresists. This treatment system, known as Supercritical CO(2) Resist Remover, or SCORR, uses a two-component solvent composed of a nonhazardous, non-regulated compound, dissolved in supercritical CO(2) The solvent/treatment system has been successfully tested on metallized Si wafers coated with negative and positive photoresist, the latter both before and after ion-implantation A description of the experimental data will be presented. Based on the initial laboratory results, the project has progressed to the design and construction of prototype, single-wafer photoresist-stripping equipment. The integrated system involves a closed-loop, recirculating cycle which continuously cleans and regenerates the CO(2), recycles the dissolved solvent, and separates and concentrates the spent resist. The status of the current design and implementation strategy of a treatment system to existing IC fabrication facilities will be discussed. Additional remarks will be made on the use of a SCORR-type system for the cleaning of wafers prior to processing. C1 Univ Calif Los Alamos Natl Lab, Phys Organ Chem Grp CST12, Los Alamos, NM 87545 USA. RP Rubin, JB (reprint author), Univ Calif Los Alamos Natl Lab, Phys Organ Chem Grp CST12, Mail Stop E-537, Los Alamos, NM 87545 USA. NR 20 TC 5 Z9 5 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-2020 BN 0-7803-5495-8 J9 IEEE INT SYMP ELECTR PY 1999 BP 13 EP 20 DI 10.1109/ISEE.1999.765840 PG 8 WC Engineering, Environmental; Engineering, Electrical & Electronic; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BN37R UT WOS:000081721000003 ER PT S AU Holmes, VP Linebarger, JM Miller, DJ Vandewart, RL AF Holmes, VP Linebarger, JM Miller, DJ Vandewart, RL BE Bruzzone, AG Uhrmacher, A Page, EH TI The simulation Intranet Architecture SO PROCEEDINGS OF THE 1999 INTERNATIONAL CONFERENCE ON WEB-BASED MODELING AND SIMULATION SE SIMULATION SERIES LA English DT Proceedings Paper CT 1999 Western MultiConference (WMC) CY JAN 17-20, 1999 CL SAN FRANCISCO, CA SP Soc Comp Simulat Int DE distributed computing; Intranet; framework architecture; CORBA; high performance simulations AB The Simulation Intranet (SI) is a term which is being used to describe one element of a multidisciplinary distributed and distance computing initiative known as DisCom(2) at Sandia National Laboratory (http et al. 1998). The Simulation Intranet is an architecture for satisfying Sandia's long term goal of providing an end-to-end set of services for high fidelity full physics simulations in a high performance, distributed, and distance computing environment. The Intranet Architecture group was formed to apply current distributed object technologies to this problem. For the hardware architectures and software models involved with the current simulation process, a CORBA-based architecture is best suited to meet Sandia's needs. This paper presents the initial design and implementation of this Intranet based on a three-tier Network Computing Architecture(NCA). The major parts of the architecture include: the Web Client, the Business Objects, and Data Persistence. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Holmes, VP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0735-9276 BN 1-56555-156-7 J9 SIMUL SERIES PY 1999 VL 31 IS 3 BP 95 EP 104 PG 10 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Computer Science GA BN24C UT WOS:000081234900015 ER PT S AU Long, J Spencer, P Springmeyer, R AF Long, J Spencer, P Springmeyer, R BE Bruzzone, AG Uhrmacher, A Page, EH TI Simtracker - Using the web to track computer simulation results SO PROCEEDINGS OF THE 1999 INTERNATIONAL CONFERENCE ON WEB-BASED MODELING AND SIMULATION SE SIMULATION SERIES LA English DT Proceedings Paper CT 1999 Western MultiConference (WMC) CY JAN 17-20, 1999 CL SAN FRANCISCO, CA SP Soc Comp Simulat Int DE computer software; documentation; metadata; data management AB Large-scale computer simulations, a hallmark of computing at Lawrence Livermore National Laboratory (LLNL), often take days to run and can produce massive amounts of output. The typical environment of many LLNL scientists includes multiple hardware platforms, a large collection of eclectic software applications, data stored on many devices in many formats, and little standard metadata, which is accessible documentation about the data. The exploration of simulation results has become a laborious process requiring knowledge of this complex environment and many application programs. We have addressed this problem by developing a web-based approach for exploring simulation results either during a calculation or afterwards. The SimTracker tool automatically generates metadata summaries that serve as a quick overview and index to the archived results of simulations. The summaries provide convenient access to the data sets and associated analysis tools. They include graphical snapshots, pointers to associated simulation input and output files, and assorted annotations. In this paper we will present an overview of the design, implementation, and operational aspects of SimTracker. We will also discuss how it is being deployed in the environment of the Accelerated Strategic Computing Initiative (ASCI, 1997). C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Long, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0735-9276 BN 1-56555-156-7 J9 SIMUL SERIES PY 1999 VL 31 IS 3 BP 171 EP 176 PG 6 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Computer Science GA BN24C UT WOS:000081234900025 ER PT S AU Shier, W Kohut, P Davis, R Tutu, N Issupov, V AF Shier, W Kohut, P Davis, R Tutu, N Issupov, V BE Tiihonen, O TI A verification and validation program for simulators for Soviet-designed nuclear reactors SO PROCEEDINGS OF THE 2ND CSNI SPECIALIST MEETING ON SIMULATORS AND PLANT ANALYSERS SE VTT SYMPOSIA LA English DT Proceedings Paper CT 2nd CSNI Specialist Meeting on Simulators and Plant Analysers CY SEP 29-OCT 02, 1997 CL ESPOO, FINLAND SP OECD Nuclear Energy Agency, CSNI Principal Working Grp Coolant Syst Behaviour, Task Grp Thermal Hydraul Applicat, IVO Power Engn Ltd, Teollisuuden Voima Ltd AB Brookhaven National Laboratory is providing technical support to the U.S. Department of Energy as part of a program to develop and implement training simulators at nuclear power plant (NPP) sites in Russia and Ukraine. This program includes both full-scope and analytical simulators for VVER-440 and VVER-1000 reactors; these simulators will be incorporated into the staff training programs at each site. As part of the procurement and delivery of each simulator, a verification and validation(V&V) program has been developed for each of the simulators. This program includes: a training program, presented to the staff at each NPP site, on the verification and validation tasks; completion of the verification and validation procedures during the simulator acceptance test; and the final acceptance of the simulator at the NPP site. These V&V activities are discussed in this paper. C1 Brookhaven Natl Lab, Dept Adv Technol, Upton, NY 11973 USA. RP Shier, W (reprint author), Brookhaven Natl Lab, Dept Adv Technol, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TECHNICAL RESEARCH CENTRE FINLAND PI ESPOO PA INFORMATION SERVICE, PO BOX 2000, FIN-02044 VT ESPOO, FINLAND SN 0357-9387 BN 951-38-5269-5 J9 VTT SYMP PY 1999 VL 194 BP 582 EP 586 PG 5 WC Computer Science, Cybernetics; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Nuclear Science & Technology SC Computer Science; Engineering; Nuclear Science & Technology GA BN92S UT WOS:000083508500048 ER PT B AU Gomberg, M Stacey, C Sayre, J AF Gomberg, M Stacey, C Sayre, J GP USENIX USENIX TI Scalable, remote administration of windows NT SO PROCEEDINGS OF THE 2ND LARGE INSTALLATION SYSTEMS ADMINISTRATION OF WINDOWS NT CONFERENCE LA English DT Proceedings Paper CT 2nd Large Installation System Administration of Windows NT Conference CY JUL 14-17, 1999 CL SEATTLE, WA SP USENIX Assoc, SAGE AB In the UNIX community there is an overwhelming perception that NT is impossible to manage remotely and that NT administration doesn't scale. This was essentially true with earlier versions of the operating system. Even today, out of the box, NT is difficult to manage remotely. Many tools, however, now make remote management of NT not only possible, but under some circumstances very easy. In this paper we discuss how we at Argonne's Mathematics and Computer Science Division manage all our NT machines remotely from a single console, with minimum locally installed software overhead. We also present NetReg, which is a locally developed tool for scalable registry management. NetReg allows us to apply a registry change to a specified set of machines. It is a command line utility that can be run in either interactive or batch mode and is written in Perl for Win32, taking heavy advantage of the Win32::TieRegistry module. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Gomberg, M (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU USENIX ASSOC PI BERKELEY PA SUITE 215, 2560 NINTH ST, BERKELEY, CA 94710 USA BN 1-880446-30-8 PY 1999 BP 1 EP 9 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA BN61M UT WOS:000082355600001 ER PT B AU Daly, G Buhrmaster, G Campbell, M Chan, A Cowles, R Denys, E Hancox, P Johnson, B Leung, D Lwin, J AF Daly, G Buhrmaster, G Campbell, M Chan, A Cowles, R Denys, E Hancox, P Johnson, B Leung, D Lwin, J GP USENIX USENIX TI NT security in an open academic environment SO PROCEEDINGS OF THE 2ND LARGE INSTALLATION SYSTEMS ADMINISTRATION OF WINDOWS NT CONFERENCE LA English DT Proceedings Paper CT 2nd Large Installation System Administration of Windows NT Conference CY JUL 14-17, 1999 CL SEATTLE, WA SP USENIX Assoc, SAGE AB Stanford Linear Accelerator Center (SLAC) was faced with the need to secure its PeopleSoft/Oracle business system in an academic environment which only has a minimal firewall. To provide protected access to the database servers for NT-based users all over the site while not hindering the lab's open connectivity with the Internet, we implemented a pseudo three-tier architecture for PeopleSoft with Windows Terminal Server and Citrix MetaFrame technology. The client application and Oracle database were placed behind a firewall, and access was granted via an encrypted link to a thin client. Authentication in the future will be through two-factor token cards. NT workstations in the business system unit were further secured through switched network ports and an automated installation process that included SMB signing and disabling LM Authentication in favor of NTLMv2. The hardened workstations then accessed the business system through the Citrix Secure ICA client. How these security measures affected our mixed environment (Windows9x, Samba, Transarc AFS clients, Pathworks, developers, researchers) is discussed. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Daly, G (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU USENIX ASSOC PI BERKELEY PA SUITE 215, 2560 NINTH ST, BERKELEY, CA 94710 USA BN 1-880446-30-8 PY 1999 BP 59 EP 67 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA BN61M UT WOS:000082355600007 ER PT S AU Wishard, LA Musser, LR AF Wishard, LA Musser, LR BE Derksen, CRM Manson, CJ TI Developments in the preservation of geoscience literature SO PROCEEDINGS OF THE 33RD MEETING OF THE GEOSCIENCE INFORMATION SOCIETY: ACCRETING THE CONTINENT'S COLLECTIONS SE PROCEEDINGS OF THE GEOSCIENCE INFORMATION SOCIETY LA English DT Proceedings Paper CT 33rd Meeting of the Geoscience-Information-Society CY OCT 25-28, 1998 CL TORONTO, CANADA SP Geosci Informat Soc AB The usefulness of the geoscience literature can be measured in centuries rather than in decades. Unfortunately the bulk of the historic geoscience literature has been published on acidic paper with the result that materials are crumbling on library shelves. In addition, many volumes contain maps and illustrations often produced in color and printed on folded sheets that are either bound into the text or housed in pockets in the binding. The inclusion of these oversized, color, folded maps and illustrations have made it impractical for geoscience materials to be preserved en mass by libraries. Instead, much geoscience material has had to be preserved piece-by-piece. As a result the majority of the geoscience literature has been passed over in preservation efforts to date. Recent technological advances, however, offer some economical and viable solutions for preserving this literature. Several new technologies are described and summarized. International initiatives underway to preserve the geoscience literature are also described. C1 Penn State Univ, Earth & Mineral Sci Lib, University Pk, PA 16802 USA. RP Wishard, LA (reprint author), Sandia Natl Labs, Tech Lib, POB 5800,MS 0899, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU GEOSCIENCE INFORMATION SOC PI ALEXANDRIA PA AMERICAN GEOLOGICAL INSTITUTE, 4220 KING ST, ALEXANDRIA, VA 22302 USA SN 0072-1409 BN 0-934485-31-3 J9 P GEOS INF PY 1999 VL 29 BP 81 EP 83 PG 3 WC Geosciences, Multidisciplinary SC Geology GA BP21M UT WOS:000084418400012 ER PT S AU Kirby, B Hirst, E AF Kirby, B Hirst, E BE McBride, AE TI Load as a resource in providing ancillary services SO PROCEEDINGS OF THE AMERICAN POWER CONFERENCE, VOL 61 - I AND II SE PROCEEDINGS OF THE AMERICAN POWER CONFERENCE LA English DT Proceedings Paper CT American Power Conference, at the 61st Annual Meeting of the Illinois-Institute-of-Technology on Innovation for Economy and Reliability CY 1999 CL CHICAGO, IL SP Illinois Inst Technol C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kirby, B (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER POWER CONFERENCE ILLINOIS INST TECHNOLOGY PI CHICAGO PA CHICAGO, IL 60616 USA SN 0097-2126 J9 PROC AMER POWER CONF PY 1999 VL 61 BP 125 EP 129 PN 1&2 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Nuclear Science & Technology SC Energy & Fuels; Engineering; Nuclear Science & Technology GA BN02Z UT WOS:000080449600027 ER PT S AU Weber, DP Wei, TYC Rock, DT Brewster, RA Jonnavithula, S AF Weber, DP Wei, TYC Rock, DT Brewster, RA Jonnavithula, S BE McBride, AE TI Computational fluid dynamics (CFD) and its potential for nuclear applications SO PROCEEDINGS OF THE AMERICAN POWER CONFERENCE, VOL 61 - I AND II SE PROCEEDINGS OF THE AMERICAN POWER CONFERENCE LA English DT Proceedings Paper CT American Power Conference, at the 61st Annual Meeting of the Illinois-Institute-of-Technology on Innovation for Economy and Reliability CY 1999 CL CHICAGO, IL SP Illinois Inst Technol C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Weber, DP (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 22 TC 1 Z9 1 U1 0 U2 0 PU AMER POWER CONFERENCE ILLINOIS INST TECHNOLOGY PI CHICAGO PA CHICAGO, IL 60616 USA SN 0097-2126 J9 PROC AMER POWER CONF PY 1999 VL 61 BP 338 EP 348 PN 1&2 PG 11 WC Energy & Fuels; Engineering, Electrical & Electronic; Nuclear Science & Technology SC Energy & Fuels; Engineering; Nuclear Science & Technology GA BN02Z UT WOS:000080449600068 ER PT S AU Lynch, R AF Lynch, R BE McBride, AE TI DOE's "P-H-D" Program: A new proactive trade promotion initiative SO PROCEEDINGS OF THE AMERICAN POWER CONFERENCE, VOL 61 - I AND II SE PROCEEDINGS OF THE AMERICAN POWER CONFERENCE LA English DT Proceedings Paper CT American Power Conference, at the 61st Annual Meeting of the Illinois-Institute-of-Technology on Innovation for Economy and Reliability CY 1999 CL CHICAGO, IL SP Illinois Inst Technol C1 US DOE, Int Porgram Coordinat, Off Fossil Energy, Washington, DC USA. RP Lynch, R (reprint author), US DOE, Int Porgram Coordinat, Off Fossil Energy, Washington, DC USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER POWER CONFERENCE ILLINOIS INST TECHNOLOGY PI CHICAGO PA CHICAGO, IL 60616 USA SN 0097-2126 J9 PROC AMER POWER CONF PY 1999 VL 61 BP 603 EP 605 PN 1&2 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Nuclear Science & Technology SC Energy & Fuels; Engineering; Nuclear Science & Technology GA BN02Z UT WOS:000080449600116 ER PT B AU Shaw, BR AF Shaw, BR BE Leek, KM TI Cultural dimensions of environmental security SO PROCEEDINGS OF THE ENVIRONMENTAL SECURITY CONFERENCE ON CULTURAL ATTITTUDES ABOUT THE ENVIRONMENT AND ECOLOGY, AND THEIR CONNECTION TO REGIONAL POLITICAL STABILITY LA English DT Proceedings Paper CT 1st Annual Conference on Environmental Security CY JAN 16-17, 1998 CL UNIV WASHINGTON, SEATTLE, WA SP Pacif NW Natl Lab, Ctr Environm Secur, Pacif NW Natl Lab, Arms Control & Nonproliferat Program, Univ Washington, Jackson Sch Int Studies, Dept Polit Sci, Univ Washington, Grad Sch Publ Affairs HO UNIV WASHINGTON C1 Pacific NW Natl Lab, Natl Secur Div, Ctr Environm Secur, Washington, DC 20024 USA. EM brian.shaw@pnl.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU BEAST FABLE SOC PI KIRKSVILLE PA NE MISSOURI STATE UNIV, DIV LANGUAGE & LIT, KIRKSVILLE, MO 63501 USA BN 1-574-77065-9 PY 1999 BP 27 EP 32 PG 6 WC Area Studies; Environmental Studies; International Relations SC Area Studies; Environmental Sciences & Ecology; International Relations GA BP25C UT WOS:000084480500003 ER PT B AU Fuller, JL AF Fuller, JL BE Leek, KM TI Proceedings of the Environmental Security Conference on cultural attitudes about the environment and ecology, and their connection to regional political stability - January 16-17, 1998 - University of Washington, Seattle - Welcome address SO PROCEEDINGS OF THE ENVIRONMENTAL SECURITY CONFERENCE ON CULTURAL ATTITUDES ABOUT THE ENVIRONMENT AND ECOLOGY, AND THEIR CONNECTION TO REGIONAL POLITICAL STABILITY LA English DT Proceedings Paper CT 1st Annual Environmental Security Conference on Cultural Attitudes about the Environment and Ecology, and their Connection to Regional Political Stability CY JAN 16-17, 1998 CL UNIV WASHINGTON, SEATTLE, WA SP Pacific NW Natl Lab Ctr Environm Secur & Arms Control & Nonproliferat Program, Univ Washington, Jackson Sch Int Studies, Univ Washington, Dept Polit Sci, Univ Washington, Grad Sch Public Affairs HO UNIV WASHINGTON C1 Pacific NW Ctr Global Secur, Natl Secur Div, Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-065-9 PY 1999 BP 7 EP 8 PG 2 WC Environmental Studies; International Relations; Political Science; Public Administration SC Environmental Sciences & Ecology; International Relations; Government & Law; Public Administration GA BN66Y UT WOS:000082531400002 ER PT B AU Shaw, BR AF Shaw, BR BE Leek, KM TI Cultural dimensions of environmental security SO PROCEEDINGS OF THE ENVIRONMENTAL SECURITY CONFERENCE ON CULTURAL ATTITUDES ABOUT THE ENVIRONMENT AND ECOLOGY, AND THEIR CONNECTION TO REGIONAL POLITICAL STABILITY LA English DT Proceedings Paper CT 1st Annual Environmental Security Conference on Cultural Attitudes about the Environment and Ecology, and their Connection to Regional Political Stability CY JAN 16-17, 1998 CL UNIV WASHINGTON, SEATTLE, WA SP Pacific NW Natl Lab Ctr Environm Secur & Arms Control & Nonproliferat Program, Univ Washington, Jackson Sch Int Studies, Univ Washington, Dept Polit Sci, Univ Washington, Grad Sch Public Affairs HO UNIV WASHINGTON C1 Ctr Environm Secur, Natl Secur Div, Pacific NW Natl Lab, Washington, DC 20024 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-065-9 PY 1999 BP 27 EP 32 PG 6 WC Environmental Studies; International Relations; Political Science; Public Administration SC Environmental Sciences & Ecology; International Relations; Government & Law; Public Administration GA BN66Y UT WOS:000082531400005 ER PT B AU Christenson, TR Garino, TJ Venturini, EL AF Christenson, TR Garino, TJ Venturini, EL BE Romankiw, LT Krongelb, S Ahn, CH TI Deep x-ray lithography based fabrication of rare earth based permanent magnets and their applications to microactuators SO PROCEEDINGS OF THE FIFTH INTERNATIONAL SYMPOSIUM ON MAGNETIC MATERIALS, PROCESSES, AND DEVICES: APPLICATIONS TO STORAGE AND MICROELECTROMECHANICAL SYSTEMS (MEMS) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 5th International Symposium on Magnetic Materials, Processes, and Devices at the 194th Meeting of the Electrochemical-Society CY NOV 01-06, 1998 CL BOSTON, MA SP Electrochem Soc, Electrodeposit Div AB Precision high aspect-ratio micro molds constructed by deep x-ray lithography have been used to batch fabricate accurately shaped bonded rare-earth based permanent magnets with features as small as 5 microns and thicknesses up to 500 microns. Maximum energy products of up to 8 MGOe have been achieved with a 20%/vol. epoxy bonded melt-spun isotropic Nd2Fe14B powder composite. Using individually processed sub-millimeter permanent sections multipole rotors have been assembled. Despite the face that these permanent magnet structures are small, their magnetic field producing capability remains the same as at any scale. Combining permanent magnet structures with soft magnetic materials and micro-coils makes possible new and more efficient magnetic microdevices. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Christenson, TR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 15 TC 3 Z9 3 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-214-1 J9 ELEC SOC S PY 1999 VL 98 IS 20 BP 312 EP 323 PG 12 WC Computer Science, Hardware & Architecture; Electrochemistry; Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Computer Science; Electrochemistry; Engineering; Materials Science GA BN13H UT WOS:000080820500029 ER PT B AU Beardmore, KM Gronbech-Jensen, N AF Beardmore, KM Gronbech-Jensen, N BE Murthy, CS Srinivasan, GR Dunham, ST TI Predicting low energy dopant implant profiles in semiconductors using molecular dynamics SO PROCEEDINGS OF THE FIFTH INTERNATIONAL SYMPOSIUM ON PROCESS PHYSICS AND MODELING IN SEMICONDUCTOR TECHNOLOGY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 5th International Symposium on Process Physics and Modeling in Semiconductor Technology, at the Spring Meeting of the Electrochemical-Society CY MAY 05-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div ID STOPPING-POWER MODEL; BORON IMPLANTATION; ION-IMPLANTATION; SILICON; SIMULATION; CRYSTALLINE AB We present a highly efficient molecular dynamics scheme for calculating dopant density profiles in group-IV alloy, and III-V zinc blende structure materials. Our scheme incorporates several necessary methods for reducing computational overhead, plus a rare event algorithm to give statistical accuracy over several orders of magnitude change in the dopant concentration. The code uses a molecular dynamics (MD) model to describe ion-target interactions. Atomic interactions are described by a combination of 'many-body' and pair specific screened Coulomb potentials. Accumulative damage is accounted for using a Kinchin-Pease type model, inelastic energy loss is represented by a Firsov expression, and electronic stopping is described by a modified Brandt-Kitagawa model which contains a single adjustable ion-target dependent parameter. Thus, the program is easily extensible beyond a given validation range, and is therefore truly predictive over a wide range of implant energies and angles. The scheme is especially suited for calculating profiles due to low energy and to situations where a predictive capability is required with the minimum of experimental validation. We give examples of using our code to calculate concentration profiles and 2D 'point response' profiles of dopants in crystalline silicon and gallium-arsenide. Here we can predict the experimental profile over five orders of magnitude for <100> and <110> channeling and for non-channeling implants at energies up to hundreds of keV. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Beardmore, KM (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 29 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-224-9 J9 ELEC SOC S PY 1999 VL 99 IS 2 BP 3 EP 17 PG 15 WC Electrochemistry; Physics, Applied SC Electrochemistry; Physics GA BM89M UT WOS:000080052200001 ER PT B AU Beardmore, KM Gronbech-Jensen, N AF Beardmore, KM Gronbech-Jensen, N BE Murthy, CS Srinivasan, GR Dunham, ST TI Direct simulation of ion beam induced stressing and amorphization of silicon SO PROCEEDINGS OF THE FIFTH INTERNATIONAL SYMPOSIUM ON PROCESS PHYSICS AND MODELING IN SEMICONDUCTOR TECHNOLOGY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 5th International Symposium on Process Physics and Modeling in Semiconductor Technology, at the Spring Meeting of the Electrochemical-Society CY MAY 05-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div ID PURE AMORPHOUS-SILICON; STRUCTURAL RELAXATION; MOLECULAR-DYNAMICS; IMPLANTATION; FLOW AB Using molecular dynamics (MD) simulation, we investigate the mechanical response of silicon to high dose ion-irradiation. We employ a realistic model to directly simulate ion beam induced amorphization. Structural properties of the amorphized sample are compared with experimental data and results of other simulation studies. We find the behavior of the irradiated material is related to the rate at which it can relax. Depending upon the ability to deform, we observe either the generation of a high compressive stress and subsequent expansion of the material, or generation of tensile stress and densification. We note that statistical material properties, such as radial distribution functions are not sufficient to differentiate between the different densities of the amorphous samples. For any reasonable deformation rate, we observe an expansion of the target upon amorphization in agreement with experimental observations. This is in contrast to simulations of quenching which usually result in a denser structure relative to crystalline Si. We conclude that although there is substantial agreement between experimental measurements and simulation results, the amorphous structures being investigated may have fundamental differences; the difference in density can be attributed to local defects within the amorphous network. Finally we show that annealing simulations of our amorphized samples can lead to a reduction of high energy local defects without a large scale rearrangement of the amorphous network. This supports the proposal that defects in a-Si are analogous to those in c-Si. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Beardmore, KM (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-224-9 J9 ELEC SOC S PY 1999 VL 99 IS 2 BP 96 EP 105 PG 10 WC Electrochemistry; Physics, Applied SC Electrochemistry; Physics GA BM89M UT WOS:000080052200009 ER PT S AU Xie, JJ Chen, SP AF Xie, JJ Chen, SP BE Murthy, CS Srinivasan, GR Dunham, ST TI Ab initio calculations of As-vacancy interactions in silicon SO PROCEEDINGS OF THE FIFTH INTERNATIONAL SYMPOSIUM ON PROCESS PHYSICS AND MODELING IN SEMICONDUCTOR TECHNOLOGY SE Electrochemical Society Series LA English DT Proceedings Paper CT 5th International Symposium on Process Physics and Modeling in Semiconductor Technology, at the Spring Meeting of the Electrochemical-Society CY MAY 05-06, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div ID MOLECULAR-DYNAMICS; IMPURITY DIFFUSION; SYSTEMS; ENERGY AB Atomistic simulation of a vacancy-assisted dopant diffusion in silicon seeds details of the dopant-vacancy interaction, i.e., the potential as a functional of dopant-vacancy separations. In this paper, we present a detailed study on the energetics of As-vacancy reaction in silicon and the lattice distortions surrounding the As-vacancy defect by using an ab initio plane wave pseudopotential method and the density functional theory (DFT). A potential-energy diagram as a function of As-vacancy separation is provided, which can be used in the atomistic diffusion simulations. We also calculate the binding energy and the formation energy of different complexes such as AsV, As2V and AsV2 (V represents vacancy). We find that the stable configuration of As2V is As-V-As, while the stable configuration of AsV2 is As-V-V. The. nature of the binding between As and vacancy is explained from the lattice distortions and the change of chemical bond configuration introduced by the. As-vacancy complex. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, T-11,MS-B262, Los Alamos, NM 87545 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 0275-0171 BN 1-56677-224-9 J9 ELEC SOC S PY 1999 VL 99 IS 2 BP 165 EP 174 PG 10 WC Electrochemistry; Physics, Applied SC Electrochemistry; Physics GA BM89M UT WOS:000080052200016 ER PT B AU Zunger, A AF Zunger, A BE Cahay, M Lockwood, DJ Leburton, JP Bandyopadhyay, S TI How to describe the electronic structure of semiconductor quantum dots SO PROCEEDINGS OF THE FIFTH INTERNATIONAL SYMPOSIUM ON QUANTUM CONFINEMENT: NANOSTRUCTURES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 5th International Symposium on Quantum Confinement - Nanostructures CY NOV 02-05, 1998 CL BOSTON, MA SP Dielect Sci & Technol, Electrochem Soc, Electr, Luminescence & Display Mat Div ID PSEUDOPOTENTIAL CALCULATIONS; P METHOD; FILMS; CONFINEMENT; WIRES; SUPERLATTICES; TRANSITION; PREDICTION; ENERGIES; SURFACE AB I describe a new strategy for predicting the electronic properties of zero-dimensional semiconductor quantum dots, including the excitonic spectrum. This methodology was applied recently to both "free standing" (e.g. colloidal) and t semiconductor-embedded (e.g. self-assembled) dots. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Zunger, A (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 43 TC 0 Z9 0 U1 2 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-213-3 J9 ELEC SOC S PY 1999 VL 98 IS 19 BP 259 EP 269 PG 11 WC Electrochemistry; Engineering, Electrical & Electronic; Physics, Applied SC Electrochemistry; Engineering; Physics GA BM76B UT WOS:000079704800020 ER PT B AU Richardson, J AF Richardson, J CA ATLAS Pixel Collaboration GP CERN CERN TI The ATLAS Pixel on-detector electronics SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board AB Large advances have been made over the last two years in the development of the front-end readout electronics for the ATLAS [1] Pixel Tracker [2]. I describe here the first phase of the Pixel Demonstrator programme which involved the production of two realistic ATLAS prototype readout-chips in radiation-soft technologies, along with the first Module Controller Chip. I will also describe the design of the first fully-functional FE-chip to be submitted to a radiation-hard foundry (Temic), which is currently being fabricated. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Richardson, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 83 EP 87 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000008 ER PT B AU Mekkaoui, A Appel, JA Cancelo, G Christian, D Hoff, J Kwan, S Yarema, RJ Zimmermann, S AF Mekkaoui, A Appel, JA Cancelo, G Christian, D Hoff, J Kwan, S Yarema, RJ Zimmermann, S GP CERN CERN TI FPIX1: an advanced pixel readout chip SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board C1 Fermilab, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Mekkaoui, A (reprint author), Fermilab, Fermi Natl Accelerator Lab, POB 500,MS 222,Wilson Rd, Batavia, IL 60510 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 98 EP 102 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000010 ER PT B AU Chase, B Citterio, M Lanni, F Makowiecki, D Radeka, V Rescia, S Takai, H Ban, J Parsons, J Sippach, W AF Chase, B Citterio, M Lanni, F Makowiecki, D Radeka, V Rescia, S Takai, H Ban, J Parsons, J Sippach, W GP CERN CERN TI Characterization of the coherent noise, electromagnetic compatibility and electromagnetic interference of the ATLAS EM calorimeter front end board SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board AB The ATLAS Electromagnetic (EM) calorimeter (EMCAL) Front End Board (FEB) will be located in custom-designed enclosures solidly connected to the feedtroughs. It is a complex mixed signal board which includes the preamplifier, shaper, switched capacitor array analog memory unit (SCA), analog to digital conversion, serialization of the data and related control logic. It will be described in detail elsewhere in these proceedings. The electromagnetic interference (either pick-up from the on board digital activity, from power supply ripple or from external sources) which affects coherently large groups of channels (coherent noise) is of particular concern in calorimetry and it has been studied in detail. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Chase, B (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Rescia, Sergio/D-8604-2011; Takai, Helio/C-3301-2012 OI Rescia, Sergio/0000-0003-2411-8903; Takai, Helio/0000-0001-9253-8307 NR 3 TC 1 Z9 1 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 222 EP 226 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000034 ER PT B AU Citterio, M Kierstead, J Rescia, S AF Citterio, M Kierstead, J Rescia, S GP CERN CERN TI The atlas calorimeter preamplifier: Performance, radiation damage, electrostatic discharge resistance, reliability and manufacturing issues SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board ID LIQUID AB The requirements, design, measured specification of the ATLAS liquid argon (LAr) calorimeter preamplifiers are reviewed. The experience gained so far in production, the quality assurance and testing, as well as the reliability estimate according to MILSTRESS standard will be discussed. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Citterio, M (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Rescia, Sergio/D-8604-2011 OI Rescia, Sergio/0000-0003-2411-8903 NR 5 TC 2 Z9 2 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 237 EP 241 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000037 ER PT B AU Baumbaugh, AE Hansen, S Los, S Tschirhart, R AF Baumbaugh, AE Hansen, S Los, S Tschirhart, R GP CERN CERN TI First testbeam results for the QIE-demonstrator readout for the CMS hadronic calorimeter SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board ID HIGH-SPEED; PHOTOMULTIPLIER AB First results of QIE based electronics used to readout the HE calorimeter in the H2 testbeam at CERN are presented. Beam, LED, and calibration data are discussed along with descriptions of the system and DAQ. C1 Fermilab, CMS HCAL Readout Grp, Batavia, IL USA. RP Baumbaugh, AE (reprint author), Fermilab, CMS HCAL Readout Grp, POB 500, Batavia, IL USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 260 EP 264 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000042 ER PT B AU Blair, RE Dawson, JW Haberichter, WN Schlereth, JL Abolins, M Ermoline, Y AF Blair, RE Dawson, JW Haberichter, WN Schlereth, JL Abolins, M Ermoline, Y GP CERN CERN TI A prototype ROI builder for the second level trigger of ATLAS implemented in FPGA's SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board AB In an effort to reduce data transfer and rate requirements, the Higher Level Trigger of the ATLAS Detector uses Region of Interest (ROI) information forwarded from Level 1 Partitions on a Level 1 Accept. The ROI Builder receives these ROI fragments, which may be considerably skewed in time and may be interspersed with fragments from other events, organizes and formats from these fragments a record for each event accepted by Level 1, selects a processor to manage the event, and transfers via S-link the assembled ROI record to the target processor. The ROI Builder must fulfill these requirements at the Level 1 Trigger rate of 100 kHz while accommodating S-link flow control. A design for the ROI Builder was developed emphasizing parallelism, implemented in FPGA's, and has been run in testbeds at Saclay and CERN. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Blair, RE (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 323 EP 326 PG 4 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000055 ER PT B AU Citterio, M Kierstead, J AF Citterio, M Kierstead, J GP CERN CERN TI Are switching power supplies acceptable for the Liquid Argon calorimeter front-end electronics? SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board AB Using high power density DC-DC converters followed by linear ripple attenuators could satisfy the power requirements of the Liquid Argon (LAr) calorimeter front-end electronics. A solution based on resonant charging DC-DC converters is discussed in term of noise characteristics, radiation and magnetic field tolerance, power efficiency and reliability. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Citterio, M (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 402 EP 406 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000070 ER PT B AU Anderssen, E Bintinger, D Berry, S Bonneau, P Bosteels, M Bouvier, P Cragg, D English, R Godlewski, J Gorski, B Grohmann, S Hallewell, G Hayler, T Ilie, S Jones, T Kadlec, J Lindsay, S Miller, W Niinikoski, T Olcese, M Olszowska, J Payne, B Pilling, A Perrin, E Sandaker, G Seytre, JG Thadome, J Vacek, V AF Anderssen, E Bintinger, D Berry, S Bonneau, P Bosteels, M Bouvier, P Cragg, D English, R Godlewski, J Gorski, B Grohmann, S Hallewell, G Hayler, T Ilie, S Jones, T Kadlec, J Lindsay, S Miller, W Niinikoski, T Olcese, M Olszowska, J Payne, B Pilling, A Perrin, E Sandaker, G Seytre, JG Thadome, J Vacek, V GP CERN CERN TI Fluorocarbon evaporative cooling developments for the ATLAS Pixel and Semiconductor Tracking detectors SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board ID VAPOR-LIQUID-EQUILIBRIA; GIBBS-DUHEM INTEGRATION; MIXTURES AB We report on the development of evaporative fluorocarbon cooling for the ATLAS Pixel and Semi-Conductor Tracker (SCT) detectors. Data are presented from cooling studies on representative prototype Pixel and SCT detector thermo-structures, using perfluoro-n-propane (C3F8), -butane (C4F10), trifluoro-iodo-methane (CF3I) and custom C3F8/C4F10 mixtures. Thermophysical properties were calculated for custom mixtures. For most of the structures tested at full projected power dissipation, operation of silicon detector substrates at temperatures below -7 degrees C (required for 10 year lifetime in the radiation environment of LHC) should be possible, albeit in some cases with increases in inner diameter (I.D.) of the coolant tubes from those of the present series of prototypes. Heat transfer coefficients in the range 2-5.10(3) Wm(-2)K(-1) have been measured in a 3.6 mm I.D, heated tube dissipating 100 Watts - close to the full equivalent power (similar to 110 W) of a barrel SCT detector "stave" - over a range of power dissipations and mass flows in the above fluids. Aspects of full-scale evaporative cooling circulator design for the ATLAS experiment are discussed, together with plans for future development. C1 EO Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Anderssen, E (reprint author), EO Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 421 EP 426 PG 6 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000074 ER PT B AU O'Connor, P Gratchev, V Kandasamy, A Polychronakos, V Tcherniatine, V Parsons, J Sippach, P AF O'Connor, P Gratchev, V Kandasamy, A Polychronakos, V Tcherniatine, V Parsons, J Sippach, P GP CERN CERN TI Readout electronics for a high-rate CSC detector SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board AB A readout system for a high-rate muon Cathode Strip Chamber (CSC) is described. The system, planned for use in the forward region of the ATLAS muon spectrometer, uses two custom CMOS integrated circuits to achieve good position resolution at a flux of up to 2500 tracks/cm(2)/s. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP O'Connor, P (reprint author), Brookhaven Natl Lab, Bldg 535B,20 N Technol Dr, Upton, NY 11973 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 452 EP 456 PG 5 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000080 ER PT B AU Cancelo, GIE AF Cancelo, GIE GP CERN CERN TI Optimization of a readout architecture for pixel detectors SO PROCEEDINGS OF THE FIFTH WORKSHOP ON ELECTRONICS FOR LHC EXPERIMENTS LA English DT Proceedings Paper CT 5th Workshop on Electronics for LHC Experiments CY SEP 20-24, 1999 CL SNOWMASS, CO SP Univ Wisconsin, CERN LHCC Electr Board AB This paper analyzes in detail some theoretical aspects in the modeling of a readout architecture for pixel detectors. In fact, these problems are common to the design of data acquisition systems and other processes containing buffers and where the input and output signals can be expressed by probability density functions. It is the purpose of this paper to point out that the same type of analysis can be extended to other systems with the benefit of saving time in long Montecarlo simulations and prototype design. The example case in which this paper is based on is the readout architecture of a column-based pixel detector amplifier and discriminator chip containing more than 3000 pixels of 50 mu x 400 mu. Several readout strategies are compared searching for an optimal design, which minimizes data loss and maximizes throughput. In particular, the probability of loosing pixel hits by overflowing the readout system is minimized studying the behavior of the stochastic Markov process. Also, the communication channel bandwidths and local buffering are optimized. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Cancelo, GIE (reprint author), Fermi Natl Accelerator Lab, POB 500,MS 368,Wilson Rd, Batavia, IL 60510 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND BN 92-9083-147-2 PY 1999 BP 483 EP 488 PG 6 WC Engineering, Electrical & Electronic; Physics, Nuclear; Physics, Particles & Fields SC Engineering; Physics GA BP17Y UT WOS:000084339000086 ER PT B AU Houts, MG Poston, DI Berte, MV Emrich, WJ AF Houts, MG Poston, DI Berte, MV Emrich, WJ BE Zubrin, RM Zubrin, M TI Near-term, low-cost space fission systems SO PROCEEDINGS OF THE FOUNDING CONVENTION OF THE MARS SOCIETY, PT II LA English DT Proceedings Paper CT Founding Convention of the Mars-Society CY AUG 13-16, 1998 CL BOULDER, CO SP Mars Soc, Natl Geograph Soc, Longview Fdn, Bushnell Corp, Fisher Space Pen AB The Heatpipe Power System (HPS) is a potential, near-term, low-cost space fission power system. The Heatpipe Bimodal System (HBS) is a potential, near-term, low-cost space fission power and/or propulsion system. Both systems will be composed of independent modules, and all components use existing technology and operate within the existing database. The HPS and HBS have relatively few system integration issues; thus, the successful development of a module is a significant step toward verifying system feasibility and performance estimates. A prototypic HPS module was fabricated, and initial testing was completed in April 1997. All test objectives were accomplished, demonstrating the basic feasibility of the HPS. Fabrication of an HBS module is underway, and testing should begin in early 1999. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Houts, MG (reprint author), Univ Calif Los Alamos Natl Lab, MS K551, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA BN 0-912183-13-6 PY 1999 BP 611 EP 619 PG 9 WC Engineering, Aerospace SC Engineering GA BN78K UT WOS:000082929000017 ER PT B AU Muscatello, AC AF Muscatello, AC BE Zubrin, RM Zubrin, M TI Nutritional supplements as radioprotectors: A review and proposal SO PROCEEDINGS OF THE FOUNDING CONVENTION OF THE MARS SOCIETY, PT III LA English DT Review CT Founding Convention of the Mars-Society CY AUG 13-16, 1998 CL BOULDER, CO SP Mars Soc, Natl Geograph Soc, Longview Fdn, Bushnell Corp, Fisher Space Pen ID TUMOR-NECROSIS-FACTOR; KILLED LACTOBACILLUS-CASEI; IRRADIATED MICE; IN-VIVO; INTERNAL RADIONUCLIDES; RADIATION PROTECTION; CELLULAR CHROMATIN; GAMMA-IRRADIATION; ENHANCES SURVIVAL; ASCORBIC-ACID AB The scientific literature contains several reports that show nutritional substances, such as vitamins, minerals, and phytochemicals (plant chemicals), provide substantial radioprotective effects in animal studies. Incorporating these substances to the human diet, already voluntarily practiced by a large segment of the population, in addition to providing other favorable health effects, may also provide a radioprotective effect. This potential radioprotective effect would be very useful in mitigating the effects of occupational radiation exposure to astronauts (especially future Mars explorers), airline crews, nuclear workers, both commercial and government, and populations exposed to nuclear accidents, e.g. Chernobyl. This paper reviews the existing evidence of radioprotective effects by nutritional supplements and proposes that their efficacy be evaluated, first with animal studies, followed by human tests with astronauts and cosmonauts on long-term missions, such as to the Mir space station and the International Space Station (ISS). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Muscatello, AC (reprint author), Rocky Flats Environm Technol Site, POB 4013,T130A, Golden, CO 80401 USA. NR 119 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA BN 0-912183-14-4 PY 1999 BP 773 EP 786 PG 14 WC Engineering, Aerospace SC Engineering GA BN78L UT WOS:000082929100003 ER PT B AU Rorke, WS AF Rorke, WS GP ASPE ASPE ASPE TI Precision surveying of the National Ignition Facility SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Rorke, WS (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 25 EP 28 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400003 ER PT B AU Montesanti, RC Locke, SF Thompson, SL AF Montesanti, RC Locke, SF Thompson, SL GP ASPE ASPE ASPE TI Diamond flycutting machine for producing flat surfaces on half-meter scale diamond-turnable optics SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn DE machine design; precision machine tool; ultra-precision machining; diamond flycutter; vertical stage; diamond turning; optics; KDP crystals; National Ignition Facility (NIF) C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Montesanti, RC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 57 EP 61 PG 5 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400011 ER PT B AU Leung, KK AF Leung, KK GP ASPE ASPE ASPE TI Design analysis of the National Ignition Facility kinematic pin (NIFKP) or flexural pivot SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn AB A kinematic pin is a flexural pivot used for precision positioning. Many NASA contractors have successfully applied flexural pivots in space programs [1]. Some space program in optical communication system requires high precision design considering micro-yield stress [2] and dimensional stability of the material [3]. Kinematic pins designed for maintaining sub-micron position of focusing magnets in a particle accelerator have been successful designed [4]. Flexural pivots are also used as seismic isolators for earthquake safety design in seismic industries [5, 6]. The NIFKP is designed for precision performance and earthquake safety. It is used to register a system as a reference position in a laser beam line. The reference position is maintained by three NIFKPs on balancing of forces of these pins [7]. C1 Univ Calif Lawrence Livermore Natl Lab, Natl Ignit Facil, NIF Operat Engn, Livermore, CA 94550 USA. RP Leung, KK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Natl Ignit Facil, NIF Operat Engn, Livermore, CA 94550 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 208 EP 211 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400047 ER PT B AU Graves, VB AF Graves, VB GP ASPE ASPE ASPE TI Implementing geometric error compensation software in a PC-based controller SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Graves, VB (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 244 EP 247 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400056 ER PT B AU Bahowick, SM Horton, WR Sheridan, TG Rorke, WS Bartel, DS AF Bahowick, SM Horton, WR Sheridan, TG Rorke, WS Bartel, DS GP ASPE ASPE ASPE TI Tolerance allocations for automated insertion of optical components in the National Ignition Facility SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bahowick, SM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 308 EP 311 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400072 ER PT B AU Wilkins, PR Knight, PD Pigg, DC AF Wilkins, PR Knight, PD Pigg, DC GP ASPE ASPE ASPE TI A scanning phase-knife technique for quantitative surface slope measurements and defect identification SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wilkins, PR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 348 EP 351 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400082 ER PT B AU Jokiel, B Ziegert, JC AF Jokiel, B Ziegert, JC GP ASPE ASPE ASPE TI Sequential determination of kinematic parameters in assembled parallel kinematic mechanisms SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jokiel, B (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 456 EP 460 PG 5 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400109 ER PT B AU Wilkins, PR Knight, PD English, RE Aikens, DM AF Wilkins, PR Knight, PD English, RE Aikens, DM GP ASPE ASPE ASPE TI NIF optical specifications and means to quantify mounting stresses SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wilkins, PR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 465 EP 468 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400111 ER PT B AU Winters, SE Arnold, TJ Bliss, ES Dailey, MJ Danforth, PM Koch, JA Sacks, RA Stolz, CJ Whistler, WT Woods, BW Zacharias, RA AF Winters, SE Arnold, TJ Bliss, ES Dailey, MJ Danforth, PM Koch, JA Sacks, RA Stolz, CJ Whistler, WT Woods, BW Zacharias, RA GP ASPE ASPE ASPE TI Overview of a 2nd generation large aperture deformable mirror for the National Ignition Facility SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn AB A second generation large aperture prototype deformable mirror was designed, fabricated and tested at Lawrence Livermore National Laboratory (LLNL) for future application to the National Ignition Facility (NIF). Experimental results, collected while operating the deformable mirror in a laboratory environment demonstrate the value of a large aperture deformable mirror and that it can be predictably designed, built and operated as an alternative to making a "perfect" optical system. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Winters, SE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 513 EP 516 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400123 ER PT B AU Born, DK Syn, C Davis, P Zimmermam, M Blaedel, K Carr, J Haack, J AF Born, DK Syn, C Davis, P Zimmermam, M Blaedel, K Carr, J Haack, J GP ASPE ASPE ASPE TI An empirical survey on the influence of machining parameters on tool wear in diamond turning of large single crystal silicon optics SO PROCEEDINGS OF THE FOURTEENTH ANNUAL MEETING OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING LA English DT Proceedings Paper CT 14th Annual Meeting of the American-Society-for-Precision-Engineering CY OCT 31-NOV 05, 1999 CL MONTEREY, CA SP Amer Soc Precis Engn, Elsevier Sci Inc, European Soc Precis Engn & Nanotechnol, Japan Soc Precis Engn C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Born, DK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC PRECISION ENGINEERING PI RALEIGH PA 401 OBERLIN RD, SUITE 108, PO BOX 10826, RALEIGH, NC 27605-0826 USA BN 1-887706-22-4 PY 1999 BP 555 EP 558 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BS05K UT WOS:000168480400133 ER PT B AU Hess, JR Svoboda, JM Hoskinson, RL Hempstead, DW Jones, WB AF Hess, JR Svoboda, JM Hoskinson, RL Hempstead, DW Jones, WB BE Robert, PC Rust, RH Larson, WE TI Spatial potato seed piece placement monitoring system SO PROCEEDINGS OF THE FOURTH INTERNATIONAL CONFERENCE ON PRECISION AGRICULTURE, PTS A AND B LA English DT Proceedings Paper CT 4th International Conference on Precision Agriculture CY JUL 19-22, 1998 CL ST PAUL, MN SP Univ Minnesota, Precis Agr Ctr, Univ Minnesota, Dept Soil, Water & Climate, Univ Minnesota, Extens Serv, Amer Soc Agron, Crop Sci Soc Amer, Soil Sci Soc Amer, Soc Engn Agr, Food & Biol Sys, Amer Soc Photogrammetry & Remote Sensing AB Proper placement of potato seed pieces is important in realizing optimum yield and quality of the harvested crop. Correlation between spatial variations in yield, quality, seed spacing and field-soil attributes define opportunities to further optimize potato seed placement on spatially selective bases. A potato planter seed drop monitoring system, integrated with a global positioning system (GPS), was used to collect spatial seed drop data. Replicated seed placement plots were used to correlate seed drop monitor measurements with actual seed placement. Twenty acres of 6-in potato seed spacing produced the desired crop quality, but reduced yields to below desired returns. Statistical and artificial intelligence analysis procedures identified manageable correlation in spatial historical attribute parameters, including different seed drop rates, with potato yield and quality for entire fields. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Hess, JR (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC AGRONOMY PI MADISON PA 677 SOUTH SEGOE RD, MADISON, WI 53711 USA BN 0-89118-140-7 PY 1999 BP 653 EP 660 PG 8 WC Agricultural Economics & Policy; Agronomy; Environmental Sciences; Remote Sensing; Soil Science SC Agriculture; Environmental Sciences & Ecology; Remote Sensing GA BQ79A UT WOS:000089526200057 ER PT B AU Svoboda, JM Hess, JR Hoskinson, RL Sawyer, JW AF Svoboda, JM Hess, JR Hoskinson, RL Sawyer, JW BE Robert, PC Rust, RH Larson, WE TI Use of aerospace structural sensor technology for soil physical characterization SO PROCEEDINGS OF THE FOURTH INTERNATIONAL CONFERENCE ON PRECISION AGRICULTURE, PTS A AND B LA English DT Proceedings Paper CT 4th International Conference on Precision Agriculture CY JUL 19-22, 1998 CL ST PAUL, MN SP Univ Minnesota, Precis Agr Ctr, Univ Minnesota, Dept Soil, Water & Climate, Univ Minnesota, Extens Serv, Amer Soc Agron, Crop Sci Soc Amer, Soil Sci Soc Amer, Soc Engn Agr, Food & Biol Sys, Amer Soc Photogrammetry & Remote Sensing AB Tractor hitch pins, instrumented by NASA Langley Research Center, are being used between tractors and cultivating equipment to log the spatial variability in the mechanical resistance or drag force required for cultivation. The lNEEL Site-Specific Technologies for Agriculture (SST4Ag) research project, in collaboration with university, other federal agency and industry partners, is correlating soil physical spatial variability, measured as tillage tool drag force, with crop productivity. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Svoboda, JM (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC AGRONOMY PI MADISON PA 677 SOUTH SEGOE RD, MADISON, WI 53711 USA BN 0-89118-140-7 PY 1999 BP 1207 EP 1210 PG 4 WC Agricultural Economics & Policy; Agronomy; Environmental Sciences; Remote Sensing; Soil Science SC Agriculture; Environmental Sciences & Ecology; Remote Sensing GA BQ79A UT WOS:000089526200110 ER PT B AU Hoskinson, RL Hess, JR AF Hoskinson, RL Hess, JR BE Robert, PC Rust, RH Larson, WE TI Using the decision support system for agriculture (DSS4AG) for wheat fertilization SO PROCEEDINGS OF THE FOURTH INTERNATIONAL CONFERENCE ON PRECISION AGRICULTURE, PTS A AND B LA English DT Proceedings Paper CT 4th International Conference on Precision Agriculture CY JUL 19-22, 1998 CL ST PAUL, MN SP Univ Minnesota, Precis Agr Ctr, Univ Minnesota, Dept Soil, Water & Climate, Univ Minnesota, Extens Serv, Amer Soc Agron, Crop Sci Soc Amer, Soil Sci Soc Amer, Soc Engn Agr, Food & Biol Sys, Amer Soc Photogrammetry & Remote Sensing AB The DSS4Ag is an expert system under development at the INEEL through the Site-Specific Technologies for Agriculture (SST4Ag) precision farming research project. The system uses artificial intelligence and other computer information technologies to assist in making spatial, site-specific management decisions. Using this decision support system, we generated a variable-rate fertilizer recommendation recipe for a 135 acre wheat (Triticum aestivum L.) field with the goal of optimum economic return, not maximum yield. The field was split into blocks, alternately fertilized with the variable-rate recipe and with the uniform application method used by the farmer. The DSS4Ag fertilizer recipe reduced fertilizer costs 39.7% and yields 3.3%, which resulted in a net economic gain of 2.8% as compared with the uniform application used by the farmer. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Hoskinson, RL (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Box 1625, Idaho Falls, ID 83415 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU AMER SOC AGRONOMY PI MADISON PA 677 SOUTH SEGOE RD, MADISON, WI 53711 USA BN 0-89118-140-7 PY 1999 BP 1797 EP 1806 PG 10 WC Agricultural Economics & Policy; Agronomy; Environmental Sciences; Remote Sensing; Soil Science SC Agriculture; Environmental Sciences & Ecology; Remote Sensing GA BQ79A UT WOS:000089526200162 ER PT B AU Job, PK Pisharody, M Semones, E AF Job, PK Pisharody, M Semones, E GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Dose measurements of Bremsstrahlung-produced neutrons from thick targets at the Advanced Photon Source SO PROCEEDINGS OF THE FOURTH SPECIALISTS MEETING ON SHIELDING ASPECTS OF ACCELERATORS, TARGETS AND IRRADIATION FACILITIES SE OECD PROCEEDINGS LA English DT Proceedings Paper CT 4th Specialists Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF 4) CY SEP 17-18, 1998 CL KNOXVILLE, TN SP OECD, Nucl Energy Agcy, Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Reactor Phys Comm Japan, Shielding Working Grp AB Bremsstrahlung is produced in the Advanced Photon Source storage ring when the positron beam interacts with the storage ring components or with the residual gas molecules in the storage ring vacuum. This bremsstrahlung has an energy range of zero to 7.0 GeV, which is the maximum energy of the positron beam. Bremsstrahlung photons of sufficiently high energy can interact with beam line components such as beam stops and collimators, generating neutrons of varying energies. This paper presents the results of simultaneous measurements, conducted at the Advanced Photon Source, of bremsstrahlung and the corresponding photoneutron production from thick targets of iron, copper, tungsten and lead, which allow one to correlate photoneutron dose rates from these metals as a function of bremsstrahlung power. The average photoneutron dose equivalent rates, normalised to the bremsstrahlung power, are measured as 2.7 +/- 0.5 rem/h/W for iron, 3.2 +/- 0.5 rem/h/W for copper, 3.9 +/- 05 rem/h/W for tungsten and 4.6 +/- 0.8 rem/h/W for lead targets. These are measured at 80 cm lateral from the centre of the targets, perpendicular to the photon beam direction. C1 Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. RP Job, PK (reprint author), Argonne Natl Lab, Expt Facil Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17044-8 J9 OECD PROC PY 1999 BP 17 EP 24 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20J UT WOS:000081061900002 ER PT B AU Job, PK Pisharody, M Semones, E AF Job, PK Pisharody, M Semones, E GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Further measurements of Bremsstrahlung from the insertion device beam lines of the Advanced Photon Source SO PROCEEDINGS OF THE FOURTH SPECIALISTS MEETING ON SHIELDING ASPECTS OF ACCELERATORS, TARGETS AND IRRADIATION FACILITIES SE OECD PROCEEDINGS LA English DT Proceedings Paper CT 4th Specialists Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF 4) CY SEP 17-18, 1998 CL KNOXVILLE, TN SP OECD, Nucl Energy Agcy, Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Reactor Phys Comm Japan, Shielding Working Grp AB Bremsstrahlung is produced in the Advanced Photon Source (APS) storage ring when the positron beam interacts with the storage ring components or with the residual gas molecules in the storage ring vacuum. The interaction of the positrons with the gas molecules occurs continually during storage ring operation. Bremsstrahlung is important at the insertion device straight sections because the contribution from each interaction adds up to produce a narrow mono-directional beam that travel down the beam lines. At the APS, with long storage ring beam straight paths (15.38 meters), gas bremsstrahlung in the insertion device beam lines can be significant. The preliminary results of the bremsstrahlung measurements in the insertion device beam lines of the APS was presented at SATIF-3. This paper presents the results of further measurements at the two insertion device (ID) beam lines with higher statistics in the data collection. The beam current and the vacuum normalised bremsstrahlung power is fairly constant in a beam line for a given storage ring fill pattern, but may vary from beam line to beam line. The average bremsstrahlung power is measured as 118 +/- 9 GeV/s/nT/mA at beam line 11 ID and as 36 +/- 2 GeV/s/nT/mA at beam line 6 ID. These results, along with the results from the four previous independent bremsstrahlung measurements, enabled us to conclude upon the various reasons causing this variation. C1 Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. RP Job, PK (reprint author), Argonne Natl Lab, Expt Facil Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17044-8 J9 OECD PROC PY 1999 BP 25 EP 33 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20J UT WOS:000081061900003 ER PT B AU Johnson, JO AF Johnson, JO GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Shielding design of the Spallation Neutron Source (SNS) SO PROCEEDINGS OF THE FOURTH SPECIALISTS MEETING ON SHIELDING ASPECTS OF ACCELERATORS, TARGETS AND IRRADIATION FACILITIES SE OECD PROCEEDINGS LA English DT Proceedings Paper CT 4th Specialists Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF 4) CY SEP 17-18, 1998 CL KNOXVILLE, TN SP OECD, Nucl Energy Agcy, Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Reactor Phys Comm Japan, Shielding Working Grp AB The shielding design is important for the construction of an intense high-energy accelerator facility like the proposed Spallation Neutron Source (SNS) due to its impact on conventional facility design, maintenance operations and since the cost for the radiation shielding shares a considerable part of the total facility costs. A calculational strategy utilising coupled high energy Monte Carlo calculations and multi-dimensional discrete ordinates calculations, along with semi-empirical calculations, was implemented to perform the conceptual design shielding assessment of the proposed SNS. Biological shields have been designed and assessed for the proton beam transport system and associated beam dumps, the target station, and the target service cell and general remote maintenance cell. Shielding requirements have been assessed with respect to weight, space, and dose-rate constraints for operating, shutdown, and accident conditions. A discussion of the proposed facility design, conceptual design shielding requirements, calculational strategy, source terms, preliminary results and conclusions, and recommendations for additional analyses are presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Johnson, JO (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17044-8 J9 OECD PROC PY 1999 BP 89 EP 100 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20J UT WOS:000081061900008 ER PT B AU Ballard, WP Bielajew, AF Cullen, DE Fasso, A Filges, D Hirayama, H Hughes, HG Kawrakow, I Kensek, RP Kirk, BL Salvat, F Seltzer, SM Vaz, P AF Ballard, WP Bielajew, AF Cullen, DE Fasso, A Filges, D Hirayama, H Hughes, HG Kawrakow, I Kensek, RP Kirk, BL Salvat, F Seltzer, SM Vaz, P GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI BEEP: The benchmark exercise for electrons and photons SO PROCEEDINGS OF THE FOURTH SPECIALISTS MEETING ON SHIELDING ASPECTS OF ACCELERATORS, TARGETS AND IRRADIATION FACILITIES SE OECD PROCEEDINGS LA English DT Proceedings Paper CT 4th Specialists Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF 4) CY SEP 17-18, 1998 CL KNOXVILLE, TN SP OECD, Nucl Energy Agcy, Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Reactor Phys Comm Japan, Shielding Working Grp ID MONTE-CARLO SIMULATION; BREMSSTRAHLUNG DOSIMETRY PREDICTIONS; MULTIPLE ELASTIC-SCATTERING; 0.75 MEV ELECTRONS; CROSS-SECTIONS; BRACHYTHERAPY SOURCES; DOSE DISTRIBUTIONS; THICK TARGETS; ENERGY-LOSS; TRANSPORT AB The purpose of this exercise is to gather together a group of experts in general purpose electron/photon Monte Carlo methods to design a benchmark suite for comparison of existing public-domain Monte Carlo codes, or ones that are due to be released by the date of the release of this report - the fourth quarter of the year 2000. Through use of results of the benchmark suite, the community will have unprecedented knowledge of the dynamic range of a given code, its range of applicability and its accuracy in comparison to experimental and theoretical benchmarks. A user will also be able to gain some idea as to how efficient a code may be for certain applications and some information as to the computing resources required for certain broad classes of problems. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ballard, WP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Vaz, Pedro/K-2464-2013; Salvat, Francesc/F-8255-2016 OI Vaz, Pedro/0000-0002-7186-2359; Salvat, Francesc/0000-0002-6162-8841 NR 93 TC 0 Z9 0 U1 0 U2 3 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17044-8 J9 OECD PROC PY 1999 BP 131 EP 141 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20J UT WOS:000081061900011 ER PT B AU Manneschmidt, JB Hunter, PT Kirk, BL Sartori, E Vaz, P AF Manneschmidt, JB Hunter, PT Kirk, BL Sartori, E Vaz, P GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Progress report on the collection of computer codes and data sets for accelerator shielding analysts SO PROCEEDINGS OF THE FOURTH SPECIALISTS MEETING ON SHIELDING ASPECTS OF ACCELERATORS, TARGETS AND IRRADIATION FACILITIES SE OECD PROCEEDINGS LA English DT Proceedings Paper CT 4th Specialists Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF 4) CY SEP 17-18, 1998 CL KNOXVILLE, TN SP OECD, Nucl Energy Agcy, Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Reactor Phys Comm Japan, Shielding Working Grp AB The three specialists meetings on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF-1, SATIF-2, SATIF-3) held in Arlington, Texas (1994), Geneva, Switzerland (1996) and Sendai, Japan (1997) have produced an immense interest in the collection of computer software for accelerator shielding. The Nuclear Energy Agency Data Bank (NEA DB) and the Radiation Safety Information Computational Centre (RSICC) continue to pursue the task of collecting these codes for the interest of the community. C1 Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Oak Ridge, TN 37831 USA. RP Manneschmidt, JB (reprint author), Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, POB 2008, Oak Ridge, TN 37831 USA. RI Vaz, Pedro/K-2464-2013 OI Vaz, Pedro/0000-0002-7186-2359 NR 5 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17044-8 J9 OECD PROC PY 1999 BP 241 EP 259 PG 19 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20J UT WOS:000081061900018 ER PT B AU Mokhov, NV AF Mokhov, NV GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Recent development, benchmarking and status of the MARS code system SO PROCEEDINGS OF THE FOURTH SPECIALISTS MEETING ON SHIELDING ASPECTS OF ACCELERATORS, TARGETS AND IRRADIATION FACILITIES SE OECD PROCEEDINGS LA English DT Proceedings Paper CT 4th Specialists Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF 4) CY SEP 17-18, 1998 CL KNOXVILLE, TN SP OECD, Nucl Energy Agcy, Oak Ridge Natl Lab, Radiat Safety Informat Computat Ctr, Reactor Phys Comm Japan, Shielding Working Grp AB This paper describes the MARS code developments and benchmarking since the previous SATIF meeting in 1997. This time the main efforts have been on the physics model improvements and extensions both in the electromagnetic and strong interaction sectors. The code capabilities to simulate cascades and generate a variety of results in complex media have also been enhanced. Examples of recent applications and MARS benchmarking are presented. The code status is described. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Mokhov, NV (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17044-8 J9 OECD PROC PY 1999 BP 277 EP 286 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20J UT WOS:000081061900020 ER PT B AU Dowell, LJ Henderson, DB AF Dowell, LJ Henderson, DB BE Tentner, A TI A comprehensive, detailed simulation of the electric-power industry: Harnessing the Los Alamos National Laboratory high-performance computing infrastructure SO PROCEEDINGS OF THE HIGH PERFORMANCE COMPUTING SYMPOSIUM - HPC '99 LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE electrical engineering; policy making; power-systems simulation; restructuring AB The simulation of the U.S. electric-power infrastructure is a problem of national significance. Restructuring the U.S. electric-power infrastructure to incorporate market efficiency, with competition extending even to the household level, and the universal and growing dependence on reliable-quality electric power mandate evaluation of proposed and existing energy policies at a new level of detail. The electric-power infrastructure is a complex system consisting of hundreds of thousands of independent agents coupled by a dynamically constrained transmission system. Actions of the independent agents are governed by both economic objectives and constraints imposed by federal, state, and local policies. Purchasing decisions by millions of independent consumers constrained jointly by market policies and transmission-system realities will lead to unexpected emergent system behavior with potential consequences on reliability and quality. Testing energy policy in vivo is too expensive, too risky, and too time consuming. Prior testing of energy policy is required, and mandates computer simulation. Simulation of the electric-power infrastructure at the level of detail required for the assessment of impacts of energy policies requires highperformance computing and the analysis and validation of emergent behavior. This paper describes a method for a comprehensive simulation of the U.S. electric-power infrastructure, with detail sufficient to assess the implications of new energy policies. This simulation is being conducted at Los Alamos National Laboratory (LANL) in collaboration with EPRI and other organizations. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dowell, LJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663 MS F604, Los Alamos, NM 87545 USA. NR 15 TC 0 Z9 0 U1 3 U2 3 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-166-4 PY 1999 BP 71 EP 75 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN24B UT WOS:000081234800012 ER PT B AU Brown, PN Chang, B Dorr, MR Hanebutte, UR Woodward, CS AF Brown, PN Chang, B Dorr, MR Hanebutte, UR Woodward, CS BE Tentner, A TI Performing three-dimensional neutral particle transport calculations on Tera scale computers SO PROCEEDINGS OF THE HIGH PERFORMANCE COMPUTING SYMPOSIUM - HPC '99 LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int ID EQUATIONS AB A scalable, parallel code system to perform neutral particle transport calculations in three dimensions is presented. To utilize the hyper-cluster architecture of emerging tera scale computers, the parallel code successfully combines the MPI message passing and Pthreads paradigms. The code's capabilities are demonstrated by a shielding calculation containing over 14 billion unknowns. This calculation was accomplished on the IBM SP "ASCI-Blue-Pacific" computer located at Lawrence Livermore National Laboratory (LLNL). C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Brown, PN (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Box 808,L-561, Livermore, CA 94551 USA. RI Woodward, Carol/M-4008-2014 NR 11 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-166-4 PY 1999 BP 76 EP 81 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN24B UT WOS:000081234800013 ER PT B AU Dowell, LJ AF Dowell, LJ BE Tentner, A TI Estimation of the service areas of electric-bower substations by cellular automata SO PROCEEDINGS OF THE HIGH PERFORMANCE COMPUTING SYMPOSIUM - HPC '99 LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE electrical engineering; policy making; estimation; cellular automata; geographic information systems AB The simulation of the U.S. electric-power infrastructure is a problem of national significance. Although databases for electric-power generation and transmission sufficient for simulations of the North American transmission system are available, representations of the consumer base for dynamic simulation of the time evolution of substations' loads are not. Static databases of system peak loads are inadequate for assessment of excess transmission capacity and other topics related to industry restructuring. This paper describes a new technique for load forecasting using cellular automata to estimate the service areas of electric-power substations. This service-area estimation is a basis for coupling a synthetic population to individual substations in the model of the transmission system to describe the time evolution of the substations' loads. This methodology completes the boundary conditions required for simulation of the electric-power infrastructure by modeling both the distribution system and the consumer base. This methodology supports dynamic simulation of power flow in the transmission system; permits simulation of off-peak and time-of-day-, day-of-week-, season-, and weather-dependent power flow; and is a basis for assessing the impact of consumer choice on transmission-capacity constraints and transmission losses in the restructured electric-power industry. Because of the scale of the electric-power infrastructure of the North American continent, this methodology requires highperformance computing. This work supports the Comprehensive, Detailed Simulation of the Electric-Power Industry Project at Los Alamos National Laboratory (LANL). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dowell, LJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663 MS F604, Los Alamos, NM 87545 USA. NR 14 TC 0 Z9 0 U1 3 U2 4 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-166-4 PY 1999 BP 105 EP 109 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN24B UT WOS:000081234800018 ER PT B AU Ewing, T Tentner, A AF Ewing, T Tentner, A BE Tentner, A TI A scaleable architecture for the modeling and simulation of Intelligent Transportation Systems SO PROCEEDINGS OF THE HIGH PERFORMANCE COMPUTING SYMPOSIUM - HPC '99 LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int AB A distributed, scaleable architecture for the modeling and simulation of Intelligent Transportation Systems on a network of workstations or a parallel computer has been developed at Argonne National Laboratory. The resulting capability provides a modular framework supporting plug-in models, hardware, and live data sources; visually realistic graphics displays to support training and human factors studies; and a set of basic ITS models. The models and capabilities are described, along with a typical scenario involving dynamic rerouting of smart vehicles which send probe reports to and receive traffic advisories from a traffic management center capable of incident detection. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Ewing, T (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Ewing, Thomas/G-5396-2014 NR 8 TC 1 Z9 1 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-166-4 PY 1999 BP 170 EP 174 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN24B UT WOS:000081234800029 ER PT B AU Mahinthakumar, G Gwo, JP AF Mahinthakumar, G Gwo, JP BE Tentner, A TI Task parallel and data parallel computing for subsurface inverse characterization problems SO PROCEEDINGS OF THE HIGH PERFORMANCE COMPUTING SYMPOSIUM - HPC '99 LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE parameter identification; parallel computing; genetic algorithms; hydrology ID SCALE AB We describe two subsurface inverse characterization problems where both task parallel and data parallel computing are used on massively parallel and workstation cluster platforms. Both applications use genetic search algorithms for finding the solution given input and output tracer signals. The first application involves both task parallel and data parallel computing on a massively parallel platform and is for subsurface source zone (biological activity zone) identification. The second application involves task parallel computing on workstation clusters and is for subsurface characterization of fracture networks. Both applications are based on the manager-worker model. Because of current limitations in different message passing interfaces, the first application required communication and I/O in MPI, PVM, and NX. We expect most of the features that required the use of PVM and NX to be available in the Globus (http://www.globus.org) enabled version of MPI so that MPI could be exclusively used. In the second application all communication is performed with PVM. This application uses dynamic task scheduling to improve load balancing within a heterogeneous workstation cluster. Here we present some performance results related to speedup and scalability for both these applications. C1 Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. RP Mahinthakumar, G (reprint author), Oak Ridge Natl Lab, Ctr Computat Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-166-4 PY 1999 BP 217 EP 223 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BN24B UT WOS:000081234800037 ER PT S AU Baca, B Cassidy, A AF Baca, B Cassidy, A GP HFES HFES TI Intranet development and design that works SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc AB Making information available and easy to find is the objective of designing a good web site. A company's Intranet typically provides a great deal of information to its employees in an effort to help them better perform their jobs. If the information is available but is difficult to locate, the usefulness of this information is diminished. Sandia National Laboratories performed a redesign of its home page and has obtained a successful design which enables its employees to locate information quickly and efficiently. Three phases of usability testing were conducted to develop and optimize the home page. This paper will discuss the redesign of the Intranet home page and describe how usability studies were used to help ensure a usable design. C1 Sandia Natl Labs, Dept Stat & Human Factors, Albuquerque, NM 87185 USA. RP Baca, B (reprint author), Sandia Natl Labs, Dept Stat & Human Factors, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 777 EP 781 PG 5 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400152 ER PT S AU Grose, E Jean-Pierre, S Miller, D Goff, R AF Grose, E Jean-Pierre, S Miller, D Goff, R GP HFES HFES TI Applying usability methods to a large intranet site SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc AB This paper describes the usability design process of a project web site within Sandia National Laboratories. Most web site designers can claim no more knowledge about their users than a focus group. This paper, however, describes the use of usability techniques such as structured interviews, card sorting, and usability testing to establish a usable information structure with which project personnel can be immediately productive. First tests of the information structure after card sorting produced correct performance on almost 80% of test trials. Innovative techniques to analyze card sort results and to perform usability testing should provide some useful tools to others interested in designing sites for usability. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Grose, E (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 1 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 782 EP 786 PG 5 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400153 ER PT B AU Harvey, NR Marshall, S AF Harvey, NR Marshall, S BE Cetin, AE Akarun, L Ertuzun, A Gurcan, MN Yardimci, Y TI Restoration of archive film material using multi-dimensional soft morphological filters SO PROCEEDINGS OF THE IEEE-EURASIP WORKSHOP ON NONLINEAR SIGNAL AND IMAGE PROCESSING (NSIP'99) LA English DT Proceedings Paper CT IEEE-EURASIP Workshop on Nonlinear Signal and Image Prcessing (NSIP 99) CY JUN 20-23, 1999 CL ANTALYA, TURKEY SP European Assoc Signal Proc, IEEE Circuits & Syst Soc, IEEE Signal Proc Soc AB A method for the optimisation of 3-D grey-scale soft morphological filters using genetic algorithms is described, which has applications in the restoration of archive film material. This method extends an existing 2-D (spatial) to the 3-D (spatio-temporal) domain, thus allows the filtering to make use of the temporal nature of the corruption and hence improve its performance. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Los Alamos Natl Lab, Los Alamos, NM 87544 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU BOGAZICI UNIVERSITY BEBEK PI ISTANBUL PA FACULTY ENGINEERING DEPT CIVIL ENGINEERING, 80815 ISTANBUL, TURKEY BN 975-518-133-4 PY 1999 BP 811 EP 815 PG 5 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology SC Computer Science; Engineering; Imaging Science & Photographic Technology GA BW17S UT WOS:000181075400172 ER PT B AU Peskin, AM Andrews, AB AF Peskin, AM Andrews, AB BE Ades, M TI A stereographic visualization environment and its applications SO PROCEEDINGS OF THE INDUSTRIAL & BUSINESS SIMULATION SYMPOSIUM LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE data visualization; imaging; graphics; stereography AB A novel three-dimensional stereographic imaging system is described. It provides a vivid visual experience and provides an effective means of analyzing both data and simulation images in a multi-user collaborative environment. The facility is briefly described, and a number of applications that have utilized the facility are outlined. Among them are images pertaining to the geology of oil exploration, medical imaging, CADCAM, nuclear physics and distance education. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Upton, NY 11973 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SOC MODELING SIMULATION INT-SCS PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-167-2 PY 1999 BP 125 EP 129 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Industrial SC Computer Science; Engineering GA BN23Z UT WOS:000081232100023 ER PT J AU Najm, HN Azoury, PH Piasecki, M AF Najm, HN Azoury, PH Piasecki, M TI Hydraulic ram analysis: a new look at an old problem SO PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART A-JOURNAL OF POWER AND ENERGY LA English DT Article DE hydraulic ram; numerical modelling; pumps; water-hammer AB The discretized method of characteristics was used to develop a new numerical model for the analysis of the wave processes in the hydraulic ram. The model encompasses all parts of the device including, for the first time, the air chamber and the delivery pipe. This in turn allows a comprehensive study of the unsteady flows in the unit as the air chamber extensively interacts with the supply side of the ram. The program accounts for all possible flow states of the ram, i.e. with impulse and discharge valves closed, with both valves open and with either of the valves closed or open. The state of the partially or fully open discharge valve requires extensive and careful treatment of all physical phenomena involved, namely the transient boundary conditions, relevant to the air chamber and its connection to the drive pipe. The treatment is for the special case of constant sonic velocity in each of the ram pipes. The numerical model was validated against experimental data obtained from various test set-ups. Comparing the velocity and pressure head variations from numerical and experimental tests at selected points along the ram supply pipe performed the most stringent test. Excellent agreement was shown to exist, validating the analytical approach. C1 Sandia Natl Labs, Livermore, CA USA. RP Azoury, PH (reprint author), 850 3rd Ave, New York, NY 10022 USA. NR 32 TC 1 Z9 3 U1 6 U2 13 PU PROFESSIONAL ENGINEERING PUBLISHING LTD PI BURY ST EDMUNDS PA NORTHGATE AVENUE,, BURY ST EDMUNDS IP32 6BW, SUFFOLK, ENGLAND SN 0957-6509 J9 P I MECH ENG A-J POW JI Proc. Inst. Mech. Eng. Part A-J. Power Energy PY 1999 VL 213 IS A2 BP 127 EP 141 DI 10.1243/0957650991537491 PG 15 WC Engineering, Mechanical SC Engineering GA 210YG UT WOS:000081132700007 ER PT J AU Chan, SH He, Y Sun, JH AF Chan, SH He, Y Sun, JH TI Prediction of transient nitric oxide in diesel exhaust SO PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING LA English DT Article DE transient nitric oxide emissions; multizone combustion model; emptying and filling model; phenomenological modelling; signal reconstruction ID ENGINE AB An extended Zeldovich mechanism, which models the kinetics of nitric oxide formation, is included in a multizone combustion model. The combustion model is subsequently integrated into a well-developed emptying and filling engine code to predict the transient nitric oxide emissions in the exhaust of a diesel engine. The predicted nitric oxide emissions, in terms of ppm level, have been validated satisfactorily with the experimental results obtained from a computer-controlled dynamic engine test bed on which a fully instrumented, turbocharged, direct injection (DI) diesel engine and a fast response regenerative d.c. dynamometer are mounted. The experimental results used in the comparison were reconstructed from the nitric oxide emission signals obtained by a conventional, slow response, chemiluminescence analyser. C1 Nanyang Technol Univ, Sch Mech & Prod Engn, Singapore 639798, Singapore. Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Chan, SH (reprint author), Nanyang Technol Univ, Sch Mech & Prod Engn, Nanyang Ave, Singapore 639798, Singapore. RI Chan, Siew Hwa/F-4055-2010 OI Chan, Siew Hwa/0000-0003-0753-0488 NR 25 TC 6 Z9 7 U1 0 U2 2 PU PROFESSIONAL ENGINEERING PUBLISHING LTD PI BURY ST EDMUNDS PA NORTHGATE AVENUE,, BURY ST EDMUNDS IP32 6BW, SUFFOLK, ENGLAND SN 0954-4070 J9 P I MECH ENG D-J AUT JI Proc. Inst. Mech. Eng. Part D-J. Automob. Eng. PY 1999 VL 213 IS D4 BP 327 EP 339 DI 10.1243/0954407991526892 PG 13 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA 221CM UT WOS:000081706500002 ER PT B AU Boyle, W Rowe, P AF Boyle, W Rowe, P BE Saeb, S Francke, C TI Rock mechanics of the proposed United States nuclear waste repository SO PROCEEDINGS OF THE INTERNATIONAL WORKSHOP ON THE ROCK MECHANICS OF NUCLEAR WASTE REPOSITORIES LA English DT Proceedings Paper CT International Workshop on the Rock Mechanics of Nuclear Waste Repositories CY JUN 05-06, 1998 CL VAIL, CO SP Amer Rock Mech Assoc AB Countries worldwide have accumulated high-level radioactive waste by using nuclear materials to produce electricity, to power naval vessels, and to make nuclear weapons. This waste must be safely contained until it no longer poses a significant risk to human health and the environment. The U.S. Department of Energy (DOE) has been studying a site at Yucca Mountain, Nevada to determine whether it is a suitable place to build a geologic repository for the nation's commercial and defense spent nuclear fuel and high-level radioactive waste. The U.S. concept relies on a series of barriers, natural and engineered, to contain the waste for thousands of years and to minimize the amount of radioactive material that may eventually be transported from a repository and reach the human environment. The barriers include the chemical and physical forms of the waste, the waste packages and other engineered barriers, and the natural characteristics of the selected site. The preliminary repository design includes a long-lived waste package and takes advantage of the desert environment and hydrologic and geologic features of Yucca Mountain. The repository will rely on geologic formations that have remained relatively stable for millions of years and on long-lived engineered barriers. Total system performance assessments of the preliminary design indicate that, for 10,000 years after the repository is closed, people living near Yucca Mountain would receive little or no increase in radiation exposure. C1 US DOE, Off Project Execut, N Las Vegas, NV 89036 USA. RP Boyle, W (reprint author), US DOE, Off Project Execut, POB 30307, N Las Vegas, NV 89036 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ROCK MECHANICS ASSOC PI ALEXANDRIA PA 600 WOODLAND TERRACE, ALEXANDRIA, VA 22302 USA PY 1999 BP 65 EP 90 PG 26 WC Engineering, Civil; Engineering, Geological; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA BU63B UT WOS:000176558100003 ER PT B AU Holland, JV Michelsen, RE Powell, DR Upton, SC Thompson, DR AF Holland, JV Michelsen, RE Powell, DR Upton, SC Thompson, DR BE Chinni, MJ TI Composing simulations using persistent software components SO PROCEEDINGS OF THE MILITARY, GOVERNMENT AND AEROSPACE SIMULATION LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE agent; components; composition; framework; simulation AB The topics of software components and component-based software engineering are being explored by software professionals in academic and industrial settings. Many researchers have addressed the potential to derive a component-based approach to simulations in general, and a few have focused on military simulations in particular. The traditional process for developing large scale simulations is cumbersome, time consuming, costly, and in some cases, inadequate. In a component-based approach, functional or logical blocks of the simulation entities are represented as coherent collections of components satisfying explicitly defined interface requirements. In this approach, a simulation is a top-level aggregate comprised of a collection of components that interact with each other in the context of a simulated environment. A component may represent a simulation artifact, an agent, or any entity that can generate events affecting itself, other simulated entities, or the state of the system. The component-based approach promotes code reuse, contributes to reducing time spent validating or verifying models, and promises to reduce the cost of development while still delivering tailored simulations specific to analysis questions. The Integrated Virtual Environment for Simulation (IVES) is a composition-centered framework to achieve this potential. IVES is a lava implementation of simulation composition concepts developed at Los Alamos National Laboratory for use in several application domains. In this paper, its use in the military domain is demonstrated via the simulation of dismounted infantry in an urban environment. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Holland, JV (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-168-0 PY 1999 BP 163 EP 170 PG 8 WC Engineering, Aerospace; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Engineering; Computer Science GA BN23Y UT WOS:000081223500027 ER PT S AU King, PE Yim, SCS AF King, PE Yim, SCS BE Chung, JS Olagnon, M Kim, CH Francescutto, A TI Primary resonance response of a controlled ocean system SO PROCEEDINGS OF THE NINTH (1999) INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL III, 1999 SE International Offshore and Polar Engineering Conference Proceedings LA English DT Proceedings Paper CT 9th International Offshore and Polar Engineering Conference (ISOPE-99) CY MAY 30-JUN 04, 1999 CL BREST, FRANCE SP Int Soc Offshore & Polar Engineers, Canadian Assoc Petr Producers, Amer Soc Civil Engineers, Engn Mech Div, Korea Comm Ocean Resources & Engn, Canadian Civil Engineers, Engn Mech Div, Chinese Soc Ocean Engineers, Chinese Soc Naval Architects & Marine Engineers, Chinese Soc Theoret & Applied Mech, Russian Acad Sci, Singapore Struct Steel Soc, Norwegian Petr Soc, Inst Engineers Australia, Kansai Soc Naval Architects, Japan, IRO, Netherlands, Tech Res Ctr Finland, Soc Mat Sci, Japan, Offshore Engn Soc, UK, Ukraine Soc Mech Engineers, IFREMER, France, Scott Polar Res Inst, UK, Inst Engineers Indonesia, Brazilian Soc Naval Architects & Marine Engineers DE moored structure; primary resonance; nonlinear; control; feedback ID CHAOTIC DYNAMIC-SYSTEMS; PERIODIC-ORBITS AB The complex oscillations of a nonlinear ocean structural system have been identified in the system model and verified through experiment. The structural system considered is characterized by nonlinear excitation and restoring forces and is modeled as a system of first order ordinary differential equations. The model takes into account a geometric nonlinearity in the restoring force, a viscous drag and periodic excitation. In this paper, a means of actively controlling the nonlinear oscillation is addressed. When applied, the controller is able to drive the dynamical system to periodic oscillations of arbitrary periodicity. The proposed control methodology applies small perturbations to the nonlinear system at prescribed intervals in order to guide a trajectory towards a stable operating state. This is accomplished by creating a locally linear map of the nonlinear system about a desired trajectory and then designing a feedback controller in order to ensure that the linearized system is stable. C1 US DOE, Albany Res Ctr, Albany, OR USA. RP King, PE (reprint author), US DOE, Albany Res Ctr, Albany, OR USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU INTERNATIONAL SOCIETY OFFSHORE& POLAR ENGINEERS PI CUPERTINO PA PO BOX 189, CUPERTINO, CA 95015-0189 USA SN 1098-6189 BN 1-880653-42-7 J9 INT OFFSHORE POLAR E PY 1999 BP 596 EP 600 PG 3 WC Geochemistry & Geophysics; Engineering, Marine; Mechanics; Oceanography SC Geochemistry & Geophysics; Engineering; Mechanics; Oceanography GA BN17X UT WOS:000080988000087 ER PT B AU Alexander, DE Rehn, LE Odette, GR Lucas, GE Klingensmith, D Gragg, D AF Alexander, DE Rehn, LE Odette, GR Lucas, GE Klingensmith, D Gragg, D BE Bruemmer, S Ford, P Was, G TI Understanding the role of defect production in radiation embrittlement of reactor pressure vessels SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int ID RESOLUTION ELECTRON-MICROSCOPY; DISPLACEMENT CASCADES; MICROSTRUCTURAL EVOLUTION; COMPUTER-SIMULATION; IRRADIATION; COPPER; ALLOYS; DAMAGE; IRON; PRECIPITATION AB Comparative experiments using high energy (10 MeV) electrons and test reactor neutrons have been undertaken to understand the role that primary damage state has on hardening (embrittlement) induced by irradiation at 300 degreesC. Electrons produce displacement damage primarily by low energy atomic recoils, while fast neutrons produce displacements from considerably higher energy recoils. Comparison of changes resulting from neutron irradiation, in which nascent point defect clusters can form in dense cascades, with electron irradiation, where cascade formation is minimized, can provide insight into the role that the in-cascade point defect clusters have on the mechanisms of embrittlement. Tensile property changes induced by 10 MeV electrons or test reactor neutron irradiations of unalloyed iron and an Fe-0.9 wt.% Cu-1.0 wt.% Mn alloy were examined in the damage range of 9.0x10(-5) dpa to 1.5x10(-2) dpa. The results to date showed the ternary alloy experienced substantially greater embrittlement in both the electron and neutron irradiated samples relative to unalloyed iron. Surprisingly, despite their disparate nature of defect production, similar embrittlement trends with increasing radiation damage were observed for electrons and neutrons in both the ternary and unalloyed iron. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Alexander, DE (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 827 EP 833 PG 7 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700087 ER PT B AU Chung, HM Ruther, WE Strain, RV Shack, WJ Karlsen, TM AF Chung, HM Ruther, WE Strain, RV Shack, WJ Karlsen, TM BE Bruemmer, S Ford, P Was, G TI Irradiation-assisted stress corrosion cracking of model austenitic stainless steels SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int DE austenitic stainless steels; irradiation; transgranular and intergranular stress corrosion; cracking; ductility; yield strength; silicone; chromium AB Slow-strain-rate tensile tests (SSRTs) were conducted on model austenitic stainless steel (SS) alloys that were irradiated at 289 degreesC in He. After irradiation to approximate to0.3 x 10(21) n.cm(-2) and approximate to0.9 x 10(21), n.cm(-2) (E > 1 MeV), significant heat-to-heat variations in the degree of intergranular and transgranular stress corrosion cracking (IGSCC and TGSCC) were observed. At approximate to0.3 x 10(21) n.cm(-2), a high-purity heat of Type 316L SS that contains a very low concentration of Si exhibited the highest susceptibility to IGSCC. In unirradiated state, Types 304 and 304L SSs did not exhibit a systematic effect of Si content on alloy strength. However, at approximate to0.3 x 10(-21)n cm(-2), yield and maximum strengths decreased significantly as Si content was increased to >0.9 wt.%. Among alloys that contain low concentrations of C and N, ductility and resistance to TGSCC and IGSCC were significantly greater for alloys with >0.9 wt.% Si than alloys with <0.47 wt.% Si. Initial data at 0.9 x 10-21n cm-2 were also consistent with the beneficial effect of high Si contents. This indicates that to delay onset of and to reduce susceptibility to irradiation-assisted stress corrosion cracking (IASCC), at least at low fluence levels, it is helpful to ensure a certain minimum concentration of Si. High concentrations of Cr were also beneficial; alloys that contain <15.5 wt.% Cr exhibited greater susceptibility to IASCC than alloys with 18 wt.% Cr, whereas an alloy that contains >21 wt.% Cr exhibited less susceptibility than the lower-Or alloys under similar conditions. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Chung, HM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 24 TC 0 Z9 0 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 931 EP 939 PG 9 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700098 ER PT B AU Chung, HM Park, JH Ruther, WE Strain, RV Sanecki, JE Zaluzec, NJ Yu, MS Yang, TT AF Chung, HM Park, JH Ruther, WE Strain, RV Sanecki, JE Zaluzec, NJ Yu, MS Yang, TT BE Bruemmer, S Ford, P Was, G TI Cracking mechanism of type 304L stainless steel core shroud welds SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int DE stainless steel weld; intergranular stress corrosion cracking; welding contamination; irradiation ID STRESS-CORROSION CRACKING; IONS AB Microstructural analyses by advanced metallographic techniques were conducted on mockup welds and a cracked BWR core shroud weld fabricated from Type 304L stainless steel. Heat-affected zones of the shroud weld and mockup shielded-metal-are welds were free of grain-boundary carbide, martensite, delta ferrite, or er depletion neat grain boundaries. However, as a result of exposure to welding fumes, the heat-affected zones of the welds were significantly contaminated by fluorine and oxygen which migrate to grain boundaries. Significant oxygen contamination promotes fluorine contamination and suppresses classical thermal sensitization even in Type 304 steels. Results of slow-strain-rate tensile tests indicate that fluorine exacerbates the susceptibility of irradiated steels to intergranular stress corrosion cracking. These observations, combined with previous reports on the strong influence of weld flux, indicate that oxygen and fluorine contamination and fluorine-catalyzed stress corrosion play a major role in cracking of Type 304L stainless steel core shroud welds. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Chung, HM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 1 Z9 1 U1 2 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 973 EP 984 PG 12 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700102 ER PT B AU Edwards, DJ Simonen, EP Bruemmer, SM AF Edwards, DJ Simonen, EP Bruemmer, SM BE Bruemmer, S Ford, P Was, G TI Radiation hardening in austenitic stainless steels irradiated in LWR's SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int ID STRESS-CORROSION CRACKING; MICROSTRUCTURAL EVOLUTION AB Austenitic stainless steels used for structural components in light-water-reactor (LWR) core internals experience considerable hardening after low dose irradiation exposure. Radiation hardening is of concern because it promotes low tensile ductility while causing large increases in the yield strength. The mechanical properties of irradiated 304SS are often different than 316SS, but the microstructural features that control radiation hardening have not been well characterized for LWR components. Recently, the dose dependence of the microstructural evolution in LWR irradiated 316SS and 304SS (T-irr = 275 degreesC) has been characterized that demonstrates several important points. First, the small "black spot" damage referred to in the literature is mostly composed of Frank loops as small as 1 nm. Secondly, while the radiation hardening at 275 degreesC saturates at around 5-10 dpa, a significant fraction of the hardening occurs at doses of 1 dpa or less, where the microstructure is dominated by small faulted dislocation loops. The final point is that overall the microstructures in commercial 316SS and 304SS after irradiation at similar to 275 degreesC are very similar in both size and density of Frank loops. C1 Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Edwards, DJ (reprint author), Battelle Mem Inst, Pacific NW Natl Lab, POB 999,MSIN P8-15, Richland, WA 99352 USA. NR 17 TC 1 Z9 1 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 1007 EP 1013 PG 7 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700105 ER PT B AU Garner, FA Porollo, SI Vorobjev, AN Konobeev, YV Dvoriashin, AM AF Garner, FA Porollo, SI Vorobjev, AN Konobeev, YV Dvoriashin, AM BE Bruemmer, S Ford, P Was, G TI Void swelling at low displacement rates in annealed X18H10T stainless steel at 30-56 DPA and 280-332 degrees C SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int ID IRRADIATION CREEP AB In reactor applications where Western countries typically use annealed AISI 304 stainless steel, it is the Russian practice to use annealed X18H10T, a titanium-stabilized 18Cr-10Ni stainless steel. Using a flow restrictor component from the low-flux breeder zone of the BN-350 reactor in Kazakhstan, it was possible to examine the behavior of void swelling at PWR-relevant temperatures and displacement rates. The temperature of this component ranged from 270-340 degreesC with a peak dose rate of 1.6 x 10(-7) dpa/sec and a peak dose of 56 dpa. Careful sectioning of the component has yielded a large number of microscopy specimens over a PWR-relevant range of temperatures and displacement rates. Microstructural data are presented and show that void swelling at 25-35 dpa persists down to similar to 306 degreesC for dose rates on the order of 1 x 10(-7) dpa/sec. At higher temperatures swelling begins at lower dpa levels. C1 Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Garner, FA (reprint author), Battelle Mem Inst, Pacific NW Natl Lab, POB 999,MSIN P8-15, Richland, WA 99352 USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 1051 EP 1058 PG 8 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700110 ER PT B AU Bruemmer, SM Edwards, DJ Arey, BW Charlot, LA AF Bruemmer, SM Edwards, DJ Arey, BW Charlot, LA BE Bruemmer, S Ford, P Was, G TI Microstructural, microchemical and hardening evolution in LWR-irradiated austenitic stainless steel SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int ID STRESS-CORROSION CRACKING AB A comprehensive characterization of pressurized-water-reactor (PWR) irradiated, Type 348 and 304 stainless steels has been performed documenting radiation dose effects on material microstructure, microchemistry and hardness. Individual heats were selected based on their susceptibility or resistance to irradiation assisted stress corrosion cracking (IASCC) during in-core swelling mandrel experiments. Characterization of irradiated and non-irradiated materials included defect microstructures by transmission electron microscopy (TEM), grain boundary composition by analytical TEM and by scanning Auger microscopy, helium transmutation by isotope-dilution mass spectrometry and strength determinations by hot hardness. Detailed comparisons were made between IASCC-susceptible and IASCC-resistant heats in order to assess radiation-induced material changes that may influence cracking response. Differences in radiation-induced microstructures and microchemistries were observed among the 348SS heats to rationalize IASCC behavior, but this was not true for the 304SS heats. The paramount need to isolate variables promoting IASCC through controlled irradiations and quantitative testing will be discussed. C1 Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bruemmer, SM (reprint author), Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 1079 EP 1087 PG 9 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700113 ER PT B AU Simonen, EP Edwards, DJ Bruemmer, SM AF Simonen, EP Edwards, DJ Bruemmer, SM BE Bruemmer, S Ford, P Was, G TI Local evolution of microstructure and microchemistry near grain boundaries in irradiated austenitic stainless steels SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL DEGRADATION OF MATERIALS IN NUCLEAR POWER SYSTEMS-WATER REACTORS LA English DT Proceedings Paper CT 9th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors CY AUG 01-05, 1999 CL NEWPORT BEACH, CA SP Minerals Met & Mat Soc, Amer Nucl Soc, Natl Assoc Corros Engineers Int ID METALS AB Radiation effects on grain boundary microchemistry and near grain boundary microstructure is of critical importance for understanding irradiation-assisted stress corrosion cracking (IASCC) of light-water reactor (LWR) core internals. Radiation-induced segregation (RIS) measurements clearly establish that grain boundaries are effective sinks for point defects in austenitic stainless steels. The depletion of point defects near grain boundaries affects the expected development of microstructure that in turn affects the development of RIS profiles. In this paper, interactions between microstructural evolution and RIS are evaluated using a rate theory model for the production, and migration of point defects with solutes, grain boundaries and matrix radiation damage. Model predictions compared with measurements define critical grain boundary conditions during LWR irradiation. The saturation loop sink density significantly affects RIS at all doses. Transient densities and loop denuding have limited effects at low dose. C1 Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Simonen, EP (reprint author), Battelle Mem Inst, Pacific NW Natl Lab, Richland, WA 99352 USA. NR 20 TC 1 Z9 1 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-475-5 PY 1999 BP 1107 EP 1112 PG 6 WC Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Nuclear Science & Technology SC Metallurgy & Metallurgical Engineering; Materials Science; Nuclear Science & Technology GA BQ99S UT WOS:000165310700116 ER PT B AU Mueller, B Zawodzinski, T Bauman, J Uribe, F Gottesfeld, S De Castro, E De Marinis, M AF Mueller, B Zawodzinski, T Bauman, J Uribe, F Gottesfeld, S De Castro, E De Marinis, M BE Gottesfeld, S Fuller, TF TI Carbon cloth gas diffusion backings for high performance PEFC cathodes SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID ELECTROLYTE FUEL-CELLS AB We report results comparing the performance of polymer electrolyte fuel cells (PEFCs) using a series of variously structured carbon cloth gas diffusion backings on the cathode side of the PEFC. Backing performance is considered in light of measurements of gas permeation rate through the (dry) backing samples. Comparisons are made of backing effects in both 5 and 50 cm(2) cells, operated with a series of oxygen partial pressures in the cathode feedstream. In tests with 50 cm(2) cells, backings which exhibited 3-5 fold higher gas permeation rates (in dry state) than the standard FLAT, enabled an increase of maximum PEFC power density by about 20%. C1 Univ Calif Los Alamos Natl Lab, Elect Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Mueller, B (reprint author), Univ Calif Los Alamos Natl Lab, Elect Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 11 Z9 12 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 1 EP 9 PG 9 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600001 ER PT B AU Paddison, SJ Pratt, LR Zawodzinski, TA AF Paddison, SJ Pratt, LR Zawodzinski, TA BE Gottesfeld, S Fuller, TF TI Theoretical structures of triflic acid-water clusters and the molecular mechanism of proton dissociation SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID NAFION AB Structural and energetic information required for recently proposed quasichemical theories of solution chemistry have been obtained for clusters of water with triflic acid, CF3SO3H(H2O)(n) for n=1-6. Quantum mechanical calculations on the clusters indicate that the acid proton does not dissociate with n=1 or 2 hydrating water molecules, but does dissociate for n greater than or equal to 3 water molecule partners. The computed minimum energy structures indicate that both "Eigen" (H9O4+) (n=3,4,6) and "Zundel" (H5O2+) (n=5) structures are likely to play a role in the molecular mechanism of acid dissociation in Nafion(R). C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Paddison, SJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, POB 1663, Los Alamos, NM 87545 USA. RI Paddison, Stephen/B-2935-2014 NR 24 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 99 EP 105 PG 7 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600011 ER PT B AU Paddison, SJ Paul, R Zawodzinski, TA AF Paddison, SJ Paul, R Zawodzinski, TA BE Gottesfeld, S Fuller, TF TI Ion and water transport in a Nafion (R) membrane pore: A statistical mechanical model with molecular structure SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID POLYMER ELECTROLYTES AB With the well established importance of the coupling of water and protons through electroosmotic drag in operating PEFCs we present here a derivation of a mathematical model that focuses on the computation of the mobility of an hydronium ion through an arbitrary cylindrical pore of a PEM with a non-uniform charge distribution on the walls of the pore. The total Hamiltonian is derived for the hydronium ion as it moves through the hydrated pore and is effected by the net potential due to interaction with the solvent molecules and the pendant side chains. The corresponding probability density is derived through solution of the Liouville equation. This probability density is then used to compute the friction tensor for the hydronium ion. We find two types of contributions: (a) due to the solvention interactions for which we adopt the conventional continuum model; (b) due to the interaction between the pendant charges and the hydronium ion. The latter is a new result and displays the role of the non-uniform nature of the charge distribution on the pore wall. C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Paddison, SJ (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. RI Paddison, Stephen/B-2935-2014 NR 20 TC 17 Z9 17 U1 1 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 106 EP 120 PG 15 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600012 ER PT B AU Zawodzinski, T Springer, T Bauman, J Rockward, T Uribe, F Gottesfeld, S AF Zawodzinski, T Springer, T Bauman, J Rockward, T Uribe, F Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Performance of PEM fuel cells operating on synthetic reformate: Experimental and modeling studies SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID ELECTROLYTE; CO AB Experimental results and modeling simulating PEM Fuel Cell operation on reformed gasoline are reported. These studies cover observed and calculated effects of hydrogen dilution at the level expected from gasoline reforming and the extent of catalyst poisoning by CO under such anode operation conditions. At flow rates corresponding to less than 80% hydrogen utilization, modest losses in cell power density are observed experimentally from hydrogen dilution alone. Modeling suggests that the performance loss caused by hydrogen dilution stems primarily from combined effects of limited protonic conductivity and gas permeability within the thin film anode catalyst layer. Effects due to limited transport through the gas diffusion backing are expected to be relatively minor. Under the experimental conditions employed, little evidence was found for deleterious effects caused by internal generation of CO from CO2. Finally, we demonstrate complete tolerance to 100 ppm CO in a 40% H-2 inlet stream at stoichiometric now of 1.3, using air injection into the anode. C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Zawodzinski, T (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 2 Z9 2 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 127 EP 135 PG 9 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600014 ER PT B AU Bauman, JW Zawodzinski, TA Gottesfeld, S AF Bauman, JW Zawodzinski, TA Gottesfeld, S BE Gottesfeld, S Fuller, TF TI An investigation of transient carbon monoxide poisoning effects in polymer electrolyte fuel cells SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID PT(111); PT(100); HYDROGEN; SURFACES; CO AB We describe studies of performance decay and recovery in polymer electrolyte fuel cells in response to step changes In the level of CO in the anode feed stream. Following a step from 0 to 100 ppm CO in the hydrogen anode feed, completion of current decay at constant cell voltage of 0.6V In a 50 cm(2) cell operating at 80 degrees C with anode loading of 0.2 mg Pt cm(-2) took 300 seconds. The observed current decay is controlled by the rate of surface dosing, determined primarily, if not exclusively, by inlet flow of CO, and the non-linear dependence of anodic HOR rate on (1-theta(co)) Performance recovery In response to a pure hydrogen purge at 80 degrees C was found to be sluggish, with full recovery taking as long as 1000 seconds. The rate of recovery upon exposure to a hydrogen purge is a function of temperature and Is apparently controlled by the rate of thermal desorption of CO. Cell performance decay was found much faster (1-10 sec) for a step from 10 ppm to 200 ppm inlet CO. The recovery time was very slow (> 1500 sec) an return from 200 ppm to 10 ppm inlet. Air bleed into the anode significantly slows down decay times and shorten recovery times in operation with transient revels of CO. C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Bauman, JW (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 11 TC 4 Z9 4 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 136 EP 149 PG 14 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600015 ER PT B AU Ticianelli, EA Mukerjee, S Lee, SJ McBreen, J Giallombardo, JR De Castro, ES AF Ticianelli, EA Mukerjee, S Lee, SJ McBreen, J Giallombardo, JR De Castro, ES BE Gottesfeld, S Fuller, TF TI Electrocatalysis of CO tolerance in H-2/CO mixtures by carbon supported PtMo in a proton exchange membrane fuel cell SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID ROTATING-DISK ELECTRODE; PLATINUM-ELECTRODES; MOLECULAR-HYDROGEN; BINARY-ALLOYS; AD-ATOMS; OXIDATION; ELECTROOXIDATION; RU; METHANOL; MONOXIDE AB We report 2 to 3 fold enhancement in activity for CO oxidation in PEM fuel cell by highly dispersed carbon supported PtMo alloy nano-crystals (PtMo/C) as compared to the current state of the art PtRu/C at 85 degrees C with 100 ppm CO in H-2. The half-cell polarization characteristics show a lower susceptibility to changes as a function of temperature (below 100 degrees C) CO concentration (5-100 ppm) and alloy composition (1:1 to 1:5, Mo:Pt) in contrast to Pt/C and PtRu/C. Cyclic voltammograms show both Pt and Mo features and a redox couple involving Mo (at similar to 0.5 V). CO stripping voltammograms show two peaks, the first at low overpotentials (similar to 0.05 V) followed by a second initiated at similar to 0.5 V, the second peak is akin to oxidation of CO on WC. Preliminary analysis of the Mo K edge XANES confirmed the presence of Mo as an oxide at potentials as law as 0.0 V and the redox couple at similar to 0.5 V. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Ticianelli, EA (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RI Ticianelli, Edson/D-1560-2012 OI Ticianelli, Edson/0000-0003-3432-2799 NR 33 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 162 EP 175 PG 14 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600017 ER PT B AU Grgur, BN Markovic, NM Ross, PN AF Grgur, BN Markovic, NM Ross, PN BE Gottesfeld, S Fuller, TF TI On the mechanism of CO-tolerance of Pt-Mo alloy electrocatalysts SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID SURFACE AB A mechanism of action of Mo atoms in the Pt-Mo alloy surface for the electrooxidation of CO and H-2/CO mixtures is proposed. The Mo atoms nucleate reactive OH groups which oxidize CO adsorbed at neighboring Pt sites at much lower overpotentials than on the pure Pt surface. In the case of H-2/CO mixtures, the rate of oxidation of CO even at very low overpotential is sufficiently high such that the steady-state coverage by CO of Pt sites is significantly less than the saturation coverage, creating a steady-state level of vacant Pt sites for the oxidation of H-2 to take place at a high rate. A mathematical model is derived which produces simulated i-E curves that are in reasonable agreement with experiment. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Grgur, BN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 8 TC 3 Z9 3 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 176 EP 186 PG 11 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600018 ER PT B AU Zawodzinski, T Bauman, J Rockward, T Haridoss, P Uribe, F Gottesfeld, S AF Zawodzinski, T Bauman, J Rockward, T Haridoss, P Uribe, F Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Enhanced CO tolerance in polymer electrolyte fuel cells with PtMo anodes SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID ROTATING-DISK ELECTRODE; ELECTROOXIDATION; H-2; RU AB We demonstrate that fuel cells using supported PtMo anode electrocatalysts can exhibit excellent tolerance to 20 ppm CO in H-2. Only some of the supported PtMo samples tested appeared highly tolerant to CO. A key factor correlating with good anode performance in the presence of CO is the particle size of the supported PtMo catalyst. C1 Univ Calif Los Alamos Natl Lab, Elect Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Zawodzinski, T (reprint author), Univ Calif Los Alamos Natl Lab, Elect Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 200 EP 208 PG 9 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600020 ER PT B AU Uribe, FA Zawodzinski, T Gottesfeld, S AF Uribe, FA Zawodzinski, T Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Effect of ammonia as possible fuel impurity on PEM fuel cell performance SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div AB Effects of NH3 on PEM fuel cell performance are reported. Traces of NH3 in the anode feedstream cause a decrease in cell current. The extent of the effect depends on NH3 concentration and time of exposure of the anode to NH3. We discuss possible mechanisms by which NH3 affects cell performance. C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices, Los Alamos, NM 87545 USA. RP Uribe, FA (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices, MST-11,MS-D429, Los Alamos, NM 87545 USA. NR 4 TC 4 Z9 4 U1 0 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 229 EP 237 PG 9 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600023 ER PT B AU Thomas, SC Ren, X Gottesfeld, S AF Thomas, SC Ren, X Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Direct methanol fuel cells: Catalyst ionomer content and anode performance SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID ELECTROLYTE AB In a study of DMFC anode catalyst layers, we have found that addition of recast ionomer does not improve anode performance when some unsupported PtRu catalysts are used, It seems that the protonic conductivity of a Ru oxide component in such catalysts is sufficient to allow effective utilization of catalyst sites. To examine possible interpenetration of catalyst and membrane material, ultramicrotomed thin sections of the MEA were examined by SEM. Images of such sections have not revealed significant catalyst/membrane interpenetration, supporting the interpretation that hydrous RuOx may provide sufficient protonic conductivity in some PtRu catalyst layers prepared with no added ionomer. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Thomas, SC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI ren, xiaoming/F-3953-2011 NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 267 EP 279 PG 13 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600027 ER PT B AU Zelenay, P Thomas, SC Gottesfeld, S AF Zelenay, P Thomas, SC Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Direct methanol fuel cells: Recent progress in fuel efficiency, cell performance and performance stability SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div AB Research presented in this paper focuses on several factors affecting the performance of direct-methanol fuel cells (DMFCs), under development for either transportation or portable power applications. In particular, we discuss (i) variations in electrocatalytic activity of a variety of Pt-Ru anode catalysts, (ii) long-term stability of the anode, and (iii) crossover of methanol. We report on recent accomplishments in cell performance, fuel utilization (overall conversion efficiency), and lowering Pt loading in DMFCs designed for the potential use in automotive transportation. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zelenay, P (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 1 Z9 1 U1 0 U2 3 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 300 EP 315 PG 16 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600030 ER PT B AU Thomas, SC Ren, X Zelenay, P Gottesfeld, S AF Thomas, SC Ren, X Zelenay, P Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Direct methanol fuel cells: Cathode evaluation and optimization SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID POLYMER ELECTROLYTE; OXYGEN REDUCTION; ACID AB Direct methanol fuel cell (DMFC) performance has been improved as a result of Pt cathode optimization based upon the process of robust design. Cathode performance has been evaluated using cathode polarization curves generated from DMFC data. The effects of variation of temperature and nature of cathode backings on DMFC cathode potential were investigated. Our results show that Pt rich DMFC cathodes, operating on ambient air at 60 degrees C, can exhibit high performance of >0.85 V vs. RHE at 100 mA/cm(2). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Thomas, SC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI ren, xiaoming/F-3953-2011 NR 13 TC 3 Z9 3 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 327 EP 340 PG 14 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600032 ER PT B AU Ren, X Springer, TE Gottesfeld, S AF Ren, X Springer, TE Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Direct methanol fuel cell: Transport properties of polymer electrolyte membrane and cell performance SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div AB Methanol and water absorption in 1100 and 1200 e.w. Nafion(R) membranes was determined by weighing P2O5 dried and methanol solution equilibrated membranes. Both methanol and water absorption in the 1200 e.w. membrane is about 70-74 % of that in the 1100 e.w. membrane. The methanol cross-over rate corresponding to that in a direct methanol fuel cell (DMFC) at open circuit was measured using a voltammetric method in the DMFC configuration and under the same cell operating conditions (temperature, humidification and concentration of feed methanol solution). Accounting for the thickness difference between the membrane samples, the methanol cross-over rate through a 1200 e.w. membrane is 52 % of that through a 1100 e.w. membrane. To resolve the cathode and anode performances in an operating DMFC, a dynamic hydrogen electrode (DHE) was used as a reference electrode. Results show that in DMFC operation the cathode could be flooded due to the high water and methanol cross-over rates, especially through the 1100 e.w. membrane at a cell temperature below 80 degrees C. An increase in methanol cross-over rate as incurred by increasing the concentration of the feed methanol solution, increasing the cell operating temperature or using a membrane more permeable to methanol decreases the cathode potential of the DMFC at open circuit. As the cell current density is increased, the cathode potential of the DMFC can approach the cathode potential of a H-2/air cell, thanks to the consumption of methanol at the anode and consequent decrease in methanol cross-over rate. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ren, X (reprint author), Univ Calif Los Alamos Natl Lab, MS-D429, Los Alamos, NM 87545 USA. RI ren, xiaoming/F-3953-2011 NR 9 TC 4 Z9 4 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 341 EP 357 PG 17 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600033 ER PT B AU Wilson, MS Zawodzinski, C Gottesfeld, S AF Wilson, MS Zawodzinski, C Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Direct liquid water hydration of fuel cell membranes SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div ID POLYMER ELECTROLYTE MEMBRANES AB Direct liquid water hydration of polymer electrolyte fuel cell membranes improves cell performance and has system advantages over conventional reactant humidification schemes. The liquid hydration of the membrane is accomplished in our case by wicking water from a supply in the anode flow-field through the otherwise hydrophobic anode gas diffusion backing directly to the membrane/electrode assembly. The liquid water can be provided to the anode plenum either by injecting droplets into the hydrogen cell inlet or by integrating water channels into the anode flow-field. Conventional carbon-cloth gas diffusion backings are modified to provide the anode wicking backing by sewing in fine multifilament wicking threads using a conventional sewing machine. This simple scheme is demonstrated to provide improved performance and good stability. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Wilson, MS (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS D429, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 424 EP 434 PG 11 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600040 ER PT B AU Busick, DN Wilson, MS AF Busick, DN Wilson, MS BE Gottesfeld, S Fuller, TF TI Low-cost composite bipolar plates for PEFC stacks SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div AB With the current emphasis on more economical PEFC stacks, fuel cell developers are focusing on new technologies that offer high performance as well as low cost. One component whose cost can be considerably reduced is the bipolar plate. Besides meeting economic constraints, bipolar plates must satisfy a host of other requirements, including high electronic conductivity, low gas permeability, corrosion resistance, low weight, high strength, and manufacturability. To achieve this demanding combination of properties, we are developing new material formulations for composite bipolar plates. Commercially available, corrosion resistant thermosetting resins are combined with graphite powder to produce relatively inexpensive composite materials that satisfy current performance objectives. Traditional and non-traditional fiber reinforcements and other additives further improve the properties of the material without substantially increasing cost. Some significant advantages of these composites over existing bipolar plate materials are described, particularly in the critical areas of weight, cost, and ease of manufacture. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Busick, DN (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS D429, Los Alamos, NM 87545 USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 435 EP 445 PG 11 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600041 ER PT B AU Zawodzinski, C Wilson, MS Gottesfeld, S AF Zawodzinski, C Wilson, MS Gottesfeld, S BE Gottesfeld, S Fuller, TF TI Metal screen and foil hardware for polymer electrolyte fuel cells SO PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM ON PROTON CONDUCTING MEMBRANE FUEL CELL II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Proton Conducting Membrane Fuel Cells CY NOV 01-05, 1998 CL BOSTON, MA SP Electrochem Soc, Energy Technol Phys Electrochem, Electrochem Soc, Battery Div AB Stainless steel wire mesh screens and foils are employed as bipolar/flow-field plates in polymer electrolyte fuel cells as a low-cost alternative to machined graphite or titanium plates. Hardware performance in 100 cm(2) single cells and small stacks as well as corrosion resistance of 316 stainless steel have been evaluated. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Zawodzinski, C (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS D429, Los Alamos, NM 87545 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-221-4 J9 ELEC SOC S PY 1999 VL 98 IS 27 BP 446 EP 456 PG 11 WC Electrochemistry SC Electrochemistry GA BM63K UT WOS:000079309600042 ER PT B AU Mladineo, SV AF Mladineo, SV GP ANS ANS TI Nuclear cities initiative SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management C1 Pacific NW Natl Lab, Washington, DC 20024 USA. RP Mladineo, SV (reprint author), Pacific NW Natl Lab, 901 D St SW,Suite 900, Washington, DC 20024 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 39 EP 40 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900006 ER PT B AU Schanfein, MJ Ticknor, LO AF Schanfein, MJ Ticknor, LO GP ANS ANS TI Continuous safeguard inventory inspection: Enhanced safeguards with reduced facility impacts SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB For over two decades a continuous inventory inspection regime has been used by the International Atomic Energy Agency (IAEA) at nuclear production facilities around the world to gain enhanced safeguards assurance while reducing facility impacts. This approach is not compatible with the current Department of Energy (DOE) Order requirements for domestic safeguards. However, Los Alamos National Laboratory (LANL) has recently participated in writing the physical inventory criteria for the next version of the DOE Order and has specifically included consideration for a continuous inventory inspection regime. In addition, we are offering to demonstrate a continuous inventory inspection regime at the LANL Plutonium Facility. The primary facility benefit is the elimination of a facility-wide shutdown cleanout inventory and elimination of short time frame, high-volume inventory inspection activities. In this way, inventory inspection activities occur with facility activities instead of replacing facility activities. This results in significant facility resource leveling and production improvements. At the same time, significant improvements in safeguards assurance are gained as well. This paper will cover the basic concepts of continuous inventory inspection and give an example of how such a regime could operate in a facility, and compare the current periodic approach to safeguards inspection with a continuous approach. This example will be based on a model using active vault and processing areas. Potential operational cost savings will also be presented. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schanfein, MJ (reprint author), Los Alamos Natl Lab, POB 1663,MS E513, Los Alamos, NM 87545 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 51 EP 59 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900008 ER PT B AU Singh, SP Lewis, JC Maltsev, V AF Singh, SP Lewis, JC Maltsev, V GP ANS ANS TI Upgrade of the nuclear material protection, control and accounting system at the VNIIEF industrial zone SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The Industrial Zone at the Russian Federal Nuclear Center/ All-Russian Scientific Research Institute of Experimental Physics (RFNC/VNIIEF) consists of ten guarded areas with twenty two material balance areas (MBAs). The type of facilities in the Industrial Zone include storage sites, machine shops, research facilities and training facilities. Modernization of the Material Protection, Control and Accounting (MPC&A) System at the Industrial Zone started in 1997. This paper provides a description of the methodology/strategy used in the upgrade of the MPC&A system. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Singh, SP (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6306, Oak Ridge, TN 37831 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 60 EP 64 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900009 ER PT B AU Close, DA Anderson, RE Johnson, WS Kandarian, RM Kerr, PL Moss, CE Romero, CD Trujillo, LA Webb, GW Whitley, CR AF Close, DA Anderson, RE Johnson, WS Kandarian, RM Kerr, PL Moss, CE Romero, CD Trujillo, LA Webb, GW Whitley, CR GP ANS ANS TI Calibration of the enrichment monitor for HEU transparency SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The governments of the United States and the Russian Federation signed a bilateral Agreement in February 1993 for the United States to purchase low-enriched uranium derived from highly enriched uranium removed from dismantled Russian nuclear weapons. The Agreement calls for the establishment of transparency measures that provide both parties with confidence that the nuclear nonproliferation objectives of the Agreement are being achieved. Under the Annexes negotiated by the Transparency Review Committee, the United States has the right to install non-intrusive United States nondestructive assay instruments to independently and continuously monitor the U-235 enrichment at the blendpoint. As part of the development and demonstration of the transparency instrumentation, the Enrichment Monitor was installed on a test loop at the Paducah Gaseous Diffusion Plant (PGDP) at Paducah, Kentucky, to exhibit its ability to monitor enrichment. The Enrichment Monitor is a NaI-detector-based instrument and uses a passive gamma-ray measurement and a gamma-ray transmission measurement to measure the uranium enrichment of gaseous UF6. The Enrichment Monitor exhibited stable operation, as evident from the measured enrichment results during the demonstration. The enrichment was in very good agreement with the facility declaration. The Enrichment Monitor tracked transient operating conditions at the PGDP. The enrichment decreased unexpectedly toward the end of the demonstration, and the Enrichment Monitor responded correctly in real time to this decrease in enrichment. The measured enrichment is independent of the pressure of the UF6 process gas, the gas velocity, and mass flow rate. The Enrichment Monitor operated extremely well for this demonstration during extended periods while unattended under the extremely harsh operating conditions at the PGDP. These conditions are significantly more harsh than they will be in the Russian facilities, where the equipment will be at room temperature and noise and vibrations are minimal. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Close, DA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 111 EP 117 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900017 ER PT B AU Mihalczo, JT Mattingly, JK Valentine, TE Uckan, T Chiang, LG Perez, RB McEvers, JA Mullens, JA Hughes, SS Turner, CR Conger, M AF Mihalczo, JT Mattingly, JK Valentine, TE Uckan, T Chiang, LG Perez, RB McEvers, JA Mullens, JA Hughes, SS Turner, CR Conger, M GP ANS ANS TI Field use of NMIS at Oak Ridge SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The Nuclear Materials Identification System (NMIS), developed by the Oak Ridge National Laboratory and Oak RidgeY-12 Plant (Y-12), has been successfully used at Y-12 for nuclear material control and accountability (NMC&A). It is particularly useful in the high gamma-ray background of storage arrays and for shielded HEU. With three systems in use at Y-12, NMIS has enhanced the NMC&A capability for verification and for confirmation of materials in storage and for HEU receipts by providing capability not available or practical by other NDA methods for safeguards. It has recently cost-effectively quantified the HEU mass and enrichment of hundreds of HEU metal items to within a total spread of 5% (3 sigma) with and mean deviations for all HEU verified of + 0.2% for mass and - 0.2% for enrichment. Three cart portable systems are easily moved around with minimal impact on facility operations since no permanent dedicated floor space is required. The positive impact of NMIS at the Oak Ridge Y-12 Plant is improved and more cost effective NMC&A as well as the resolution of NMC&A findings. Its operation at the Y-12 Plant is essential for compliance with the NMC&A requirements of the U. S. Department of Energy. NMIS portability has allowed one system to be moved temporarily to the former K-25 Gaseous Diffusion Plant for characterization of a large deposit of hydrated uranyl fluoride. The impact of this NMIS application was enhanced and verified nuclear criticality safety that led to the safe removal of a large deposit originally estimated by gamma-ray spectrometry and neutron counting to contain 1300 kg of 3.3 wt% U-235 material. NMIS has also been operational at Los Alamos National Laboratory and Pantex. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Mihalczo, JT (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 118 EP 125 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900018 ER PT B AU Geist, WH Browne, MC Ensslin, N Mayo, DR Russo, PA Kusner, MR AF Geist, WH Browne, MC Ensslin, N Mayo, DR Russo, PA Kusner, MR GP ANS ANS TI Testing of a fiber/scintillator neutron-capture detector SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB A neutron detector test element consisting of layers of Li-6/scintillator-clad fiber ribbon is being modeled computationally and tested experimentally. The performance expectation of a full-size, four-sided, prototype neutron-coincidence well counter that is being manufactured commercially has been evaluated with this smaller-scale element. Performance goals for the new counter relative to polyethylene-moderated He-3 counters are equivalent neutron detection efficiency (epsilon), comparable gamma -ray discrimination capability, and shorter neutron-die-away time (T). These characteristics address sensitivity requirements that are not met by polyethylene-moderated He-3 counters for neutron-coincidence assay of plutonium residues with high, uncorrelated neutron yields. Each of the four full-size elements of the prototype counter will consist of a stack of alternating sheets of Li-6/scintillator mixed in a hydrogenous optical binder and 1-mm diameter wavelength-shifting optical fibers ribbons. The two ends of the fiber ribbons will be coupled to photomultiplier tubes (PMTS) whose outputs are used for signal processing. The scaled-down test element consists of a smaller stack of Li-6/scintillator and fiber-ribbon layers. It has been used to benchmark calculations of neutron detection efficiency and die-away time. It has also supported the evaluation of prototype electronics, including techniques to reduce gamma -ray sensitivity. Results from these studies are reported. C1 Los Alamos Natl Lab, Safeguards Sci & Technol, Grp NIS5, Los Alamos, NM 87545 USA. RP Geist, WH (reprint author), Los Alamos Natl Lab, Safeguards Sci & Technol, Grp NIS5, MS E540, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 126 EP 132 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900019 ER PT B AU Menlove, HO Stewart, JE Mayo, DR AF Menlove, HO Stewart, JE Mayo, DR GP ANS ANS TI Advanced performance epithermal neutron detector for measurement of inventory samples SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB We have developed a high-efficiency neutron detector for passive neutron coincidence and multiplicity counting of spontaneous fission neutrons. The detector uses 10-atm He-3 tubes to increase the efficiency and to shorten the neutron die-away time. We have achieved an efficiency of 80% and a die-away time of 18.8 mus by inserting a small sample coincidence counter (INVS) in the sample cavity of the Epithermal Neutron Multiplicity Counter (ENMC). The ENMC/INVS is designed for high-precision measurements of small inventory samples with diameters less than 50 mm. To make accurate background corrections for room neutrons, we use the ratio of the counts in the outer ring of detectors to the inner ring to give a real-time measure of the room background neutrons. C1 Los Alamos Natl Lab, Grp NIS5, Los Alamos, NM 87545 USA. RP Menlove, HO (reprint author), Los Alamos Natl Lab, Grp NIS5, MS E540, Los Alamos, NM 87545 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 133 EP 142 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900020 ER PT B AU Stewart, JE Bourret, SC Krick, MS Sweet, MR Li, TK Gorobets, A AF Stewart, JE Bourret, SC Krick, MS Sweet, MR Li, TK Gorobets, A GP ANS ANS TI New shift-register electronics for improved precision of neutron coincidence and multiplicity assays of plutonium and uranium mass SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Active and passive neutron-coincidence counting (NCC) is used routinely for nondestructive assay (NDA) of uranium and plutonium, in many forms. Passive neutron multiplicity counting (PNMC) is used routinely for NDA of plutonium scrap and waste. We've developed and extensively tested new electronics that significantly improves precision of double and triple coincidences, and multiplicity assays. Using both a time-correlated pulser and neutron sources, we've simulated PNMC assays (PNMAs) for a wide variety of plutonium samples. Plutonium-240-effective masses ranged from 0.1 to 200 g. The important parameter alpha [ratio of (alpha ,n) to spontaneous-fission neutrons] varied from 0 to 10. We've also tested one circuit (Fast Accidentals Sampling or FA) on Pu-oxide standards. For sources and standards measurements, representative the majority of NCC and PNMC applications, FA precision reductions relative to conventional multiplicity shift-register (CMSR) circuits, are 20-29% for doubles, and 24-31% for multiplicity assays. For Pu-240-effective masses of 50-100 g, FA gains are roughly independent of alpha. For alpha =0, FA gains are roughly independent of Pu-240-effective mass. FA sampling has been implemented in the Advanced Multiplicity Shift Register (AMSR). The AMSR, relative to CMSRs, reduces doubles measurement times by factors of 1.6 to 2.0. The reduction for PNMC assays is by factors of 1.7 to 2.1. Testing of FA sampling on plutonium was done using an integrated system: the Epithermal Neutron Multiplicity Counter (ENMC), the commercial AMSR-150, and the general-purpose international NCC software package, INCC ver. 4.00. FA sampling also significantly improves measurement precision for active NCC assays of uranium. The new electronics reduces the need for high efficiency, and therefore cost, of neutron coincidence and multiplicity counters. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Stewart, JE (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 143 EP 154 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900021 ER PT B AU Lestone, JP Pecos, JM Rennie, JA Sprinkle, JK Staples, P Grimm, KN Hill, RN Cherradi, I Islam, N Koulikov, J Starovich, Z AF Lestone, JP Pecos, JM Rennie, JA Sprinkle, JK Staples, P Grimm, KN Hill, RN Cherradi, I Islam, N Koulikov, J Starovich, Z GP ANS ANS TI Determining the plutonium content of breeder reactor spent-fuel assemblies SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The International Atomic Energy Agency is presently interested in developing equipment and techniques to measure the plutonium content of breeder reactor spent fuel and blanket assemblies located in storage ponds prior to their relocation to more secure facilities. We present the first quantitative nondestructive assay measurement of the plutonium content of fast breeder reactor spent-fuel assemblies while still underwater in their facility storage pond. We have calibrated and installed a Spent Fuel Coincidence Counter (SFCC) in a fast breeder reactor spent-fuel pond. Our SFCC has the outward appearance of a right cylinder with a hole through the axis through which a fuel assembly can pass. The outer regions of the SFCC consist of a ring of 20 He-3 tubes. The inner regions of the SFCC have a 6.8-cm-thick lead shield to attenuate fission-product gamma radiation. A procedure has been developed to convert singles and coincidence neutron rates measured at multiple positions along a given assembly into the total plutonium content of that assembly. Using limited facility information, the combined measurement and facility declaration error is approximately 10%. C1 Los Alamos Natl Lab, Grp NIS5, Los Alamos, NM 87545 USA. RP Lestone, JP (reprint author), Los Alamos Natl Lab, Grp NIS5, MS E540, Los Alamos, NM 87545 USA. NR 2 TC 0 Z9 0 U1 1 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 155 EP 161 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900022 ER PT B AU Prettyman, TH Brown, SK Catlett, DS Corlett, C Donohoue, TP Hansen, JS Hasbrouck, GD Horley, EC Kayler, LJ Lestone, JP Marks, T Muscatello, AC Pickrell, MM Rael, CD Shonrock, CO Short, DA Sweet, MR Upp, D West, JD AF Prettyman, TH Brown, SK Catlett, DS Corlett, C Donohoue, TP Hansen, JS Hasbrouck, GD Horley, EC Kayler, LJ Lestone, JP Marks, T Muscatello, AC Pickrell, MM Rael, CD Shonrock, CO Short, DA Sweet, MR Upp, D West, JD GP ANS ANS TI Development of a transportable tomographic gamma scanner for safeguards and waste measurements at Rocky Flats SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB In order to meet their goal of site closure by 2006, the Rocky Flats Environmental Technology Site must stabilize and dispose over 100 metric tons of plutonium-containing residues left over from weapons production operations. In this paper, we describe the development of a tomographic gamma scanner (TGS) to assist in meeting this goal. TGS provides high-throughput measurements of plutonium residues and transuranic (TRU) waste with accuracy and precision sufficient to meet safeguards, shipping, and disposal requirements. An overview of the development, implementation, and commercialization of this new instrument is presented. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Prettyman, TH (reprint author), Los Alamos Natl Lab, Mail Stop E540, Los Alamos, NM 87545 USA. NR 9 TC 0 Z9 0 U1 0 U2 3 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 162 EP 170 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900023 ER PT B AU Vo, DT Hansen, JS Li, TK AF Vo, DT Hansen, JS Li, TK GP ANS ANS TI Plutonium isotopic analysis using low-energy Gamma-ray Spectroscopy SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Low-Energy Gamma-ray Spectroscopy, LEGS, is a non-destructive assay (NDA) technique developed in the 1980s to address applications involving small quantities (mug to g) of plutonium in various chemical forms. The energy range from approximately 30 keV to 210 keV provides intense, well-separated gamma-rays from the principal isotopes of plutonium and, for applications such as those cited above, is ideally suited for accurate realtime or near real-time isotopic analysis. The two major sources of uncertainty in such analyses derive from the precision to which the gamma ray peak areas are measured and from one's estimate of the photo-peak efficiency for the lines corresponding to the principal isotopes. Traditionally, in the LEGS methodology, the relative efficiency for each of the lines corresponding to the principal isotopes has been found via non-linear interpolation schemes using selected lines of Pu-239 to guide the interpolation. Although historically these methods have produced excellent results, experience indicates that a model based upon the physical processes affecting the photo-peak efficiency should be more robust and inherently more reliable. With this as motivation, studies have been undertaken and the major processes controlling the energy dependent efficiency have been incorporated into a physical based model. To facilitate application of the model to systems of poorly known detector geometry and/or source to detector distance, a nonlinear correction factor has been derived that normalizes the results for general types of detectors and geometries. In particular, the correction factor for planar detectors has been derived and its applicability to similar detectors of differing size and source to detector geometries tested. Results for plutonium isotopic ratios determined via this technique are compared to mass spectrometry results. C1 Los Alamos Natl Lab, Safeguards Sci & Technol NIS5, Los Alamos, NM 87545 USA. RP Vo, DT (reprint author), Los Alamos Natl Lab, Safeguards Sci & Technol NIS5, POB 1663,Mail Stop E540, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 173 EP 178 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900024 ER PT B AU Parker, WE Wang, TF Clark, D Buckley, WM Romine, W Ruhter, WD AF Parker, WE Wang, TF Clark, D Buckley, WM Romine, W Ruhter, WD GP ANS ANS TI Plutonium and uranium isotopic analysis: Recent developments of the MGA plus plus code suite SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management ID DETECTORS AB The Lawrence Livermore National Laboratory develops sophisticated gamma-ray analysis codes for isotopic determinations of nuclear materials based on the principles of the MultiGroup Analysis (MGA). MGA methodology has been upgraded and expanded and is now comprised of a suite of codes known as MGA++. A graphical user interface has also been developed for viewing the data and the fitting procedure. The code suite provides plutonium and uranium isotopic analysis for data collected with high-purity germanium planar and/or coaxial detector systems. The most recent addition to the MGA++ code suite, MGAHI, analyzes Pu data using higher-energy gamma rays (200 keV and higher) and is particularly useful for Pu samples that are enclosed in thick-walled containers. Additionally, the code suite can perform isotopic analysis of uranium spectra collected with cadmium-zinc-telluride (CZT) detectors. We are currently developing new codes with will integrate into the MGA++ suite. These will include Pu isotopic analysis capabilities for data collected with CZT detectors, and U isotopic analysis with high-purity germanium detectors, which utilizes only higher energy gamma rays. Future development of MGA++ will include a capability for isotopic analyses on mixtures of Pu and U. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Parker, WE (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 192 EP 197 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900027 ER PT B AU Ryon, RW Ruhter, WD Rudenko, V Sirotinin, A Petrov, A AF Ryon, RW Ruhter, WD Rudenko, V Sirotinin, A Petrov, A GP ANS ANS TI Uranium and plutonium solution assays by transmission-corrected x-ray fluorescence SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB We have refined and tested a previously developed x-ray fluorescence analysis technique for uranium and plutonium solutions that compensates for variations in the absorption of the exciting gamma rays and fluorescent x-rays. We use Co-57 to efficiently excite the K lines of the elements, and a mixed Co-57 plus Gd-153 transmission source to correct for variations in absorption. The absorption correction is a unique feature of our technique. It is possible to accurately calibrate the system with a single solution standard. There does not need to be a close match in composition (i.e., absorption) between the standard(s) and solutions to be analyzed. Specially designed equipment incorporates a planar intrinsic germanium detector, excitation and transmission radioisotopes, and specimen holder. The apparatus can be inserted into a rubber glove of a glovebox, keeping the apparatus outside and the solutions inside the glovebox, thereby protecting the user and the equipment from possible contamination. An alternate design may be used in chemical reprocessing plants, providing continuous monitoring, by measuring the trans-actinides through stainless steel piping. This technique has been tested at the Bochvar Research Institute of Inorganic Materials in Moscow for possible use in the Russian complex of nuclear facilities. This is part of a cooperative program between laboratories in the United States and Russia to strengthen systems of nuclear materials protection, control, and accountability (MPC&A). A part of this program is to accurately measure and track inventories of materials, thus the need for good non-destructive analytical techniques such as the one described here. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ryon, RW (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 198 EP 205 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900028 ER PT B AU Sampson, TE Kelley, TA Vo, DT AF Sampson, TE Kelley, TA Vo, DT GP ANS ANS TI Improvements in the PC/FRAM isotopic analysis software SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB A new version of the PC/FRAM* isotopic analysis software is under development at Los Alamos National Laboratory. This version will be optimized for unattended robotic operation in the upgraded ROBOCAL automated calorimetric assay system at the Los Alamos plutonium facility and will automatically analyze samples with no prior knowledge of their isotopic content, presence of internal shielding, or presence of isotopic heterogeneities or interferences, A new physics-based relative-efficiency formalism will enhance performance on weak spectra as well as uranium and mixed oxide in shielded containers. Several other improvements are planned for improved measurement performance for uranium. Corrections for coincidence summing will allow measurements at varying distances, reducing the biases that can arise without these corrections. We will also add an isotopic correlation to predict the (23)6U value, which cannot be directly measured by gamma-ray spectrometry. The new software will also allow the user to correct for nonequilibrium U-238-Pa-234. The software will be structured in the analysis engine/user interface shell form, allowing easier customization for specific user needs. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sampson, TE (reprint author), Los Alamos Natl Lab, POB 1663,Mail Stop E540, Los Alamos, NM 87545 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 206 EP 211 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900029 ER PT B AU Charlton, WS Stanbro, WD Fearey, BL Hemberger, PH Perry, RT Poths, J AF Charlton, WS Stanbro, WD Fearey, BL Hemberger, PH Perry, RT Poths, J GP ANS ANS TI The use of stable noble gases to confirm compliance with the Fissile Material Cutoff Treaty SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The Fissile Material Cutoff Treaty could pose new problems for ensuring that spent reactor fuel is not used to provide plutonium for weapons purposes. Under the proposed treaty, the costs for inspections of such facilities by the International Atomic Energy Agency (the most probable choice of verification agency) would likely increase from the current $100 million per year. These costs make examination of alternative solutions quite attractive. This paper discusses one such alternative that uses measurements of the stable isotopes of fissiogenic noble gases for determining the burnup and reactor type of the fuel from which the gas was released. The methodology for the verification procedure is described. Also presented is a benchmark validation of the existing technique for literature measurements from light water reactor fuel. This benchmark demonstrates the technique's ability to accurately determine burnup and fuel type. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Charlton, WS (reprint author), Los Alamos Natl Lab, Mail Stop E541, Los Alamos, NM 87545 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 212 EP 219 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900030 ER PT B AU Wang, TF Ruhter, WD Lanier, RG AF Wang, TF Ruhter, WD Lanier, RG GP ANS ANS TI Re-measured uranium branching ratios and their impact on removing biases from MGAU analyses SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Biases in MGAU analyses first observed in FSU Gosatomnadzor inspection and subsequently identified in more detail by measurements at the Moscow Kurchatov Institute have forced a new look at the code's analysis assumptions. We have used uranium gamma-ray calibration standards from the National Bureau of Standards and standards from the New Brunswick Laboratory to investigate MGAU analysis biases. The 200g uranium standards which cover the uranium enrichments ranging from 0.3% to 93% were used to collect more than 500 gamma-ray spectra for this study. The experimental arrangement used a LEPS Ge detector with various source-detector configurations and absorbers. Two independent versions of the MGAU code, which we currently employ in our laboratory, confirm the biases noted in a developing variety of FSU inspection results and in the careful Kurchatov study. In this paper, we will discuss the MGAU methodology and use 250 spectra at a fixed geometry without absorbers to obtain new branching ratios for the critical 100-keV region gamma rays. We show that modifying the branching ratios removes a significant component of the observed biases. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wang, TF (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 220 EP 224 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900031 ER PT B AU York, RL Rooney, BD Close, DA Williams, HE AF York, RL Rooney, BD Close, DA Williams, HE GP ANS ANS TI Active neutron interrogation package monitor SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The increased threat of nuclear proliferation and nuclear material smuggling has resulted in the need for new technologies to monitor the unauthorized movement of special nuclear material, SNM. One technique being developed at the Los Alamos National Laboratory is using active neutron interrogation to rapidly search containers, packages, and luggage for hidden SNM. The neutron interrogation technique reveals the presence of the SNM even when it is so heavily shielded that no gamma signature is present. A pulse of thermal and epithermal neutrons is used to induce fissions in the hidden SNM. Arrays of He-3 detectors positioned around the package detect the fission neutrons in a time interval that is distinct from the interrogating flux. The detection technique can be completely automated with interrogation times of less than one minute and without residual radiation. The design and operation of the instrument to enhance the SNM detection in the presence of shielding will be discussed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP York, RL (reprint author), Los Alamos Natl Lab, Mail Stop J562, Los Alamos, NM 87545 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 225 EP 228 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900032 ER PT B AU Hoida, HW Lanier, R Schultz, F Volodin, Y Khrokalo, I Mintjukov, P Mathews, C AF Hoida, HW Lanier, R Schultz, F Volodin, Y Khrokalo, I Mintjukov, P Mathews, C GP ANS ANS TI The DOE/Gosatomnadzor collaboration, project 3: Providing equipment and measurement support for Gosatomnadzor inspection activities in Russia SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Gosatomnadzor (GAN) is the "Federal Radiation and Nuclear Safety Authority of Russia." GAN regulates the use of civilian nuclear material for peaceful purposes. GAN's headquarters are in Moscow, and there are seven regional offices containing technical support groups with resident inspectors. There are nineteen field offices with resident inspectors co-located at the largest sites. These inspectors inspect their local sites, while other sites are inspected by the regional office. For some inspections, the field and regional offices may combine forces. GAN regulatory oversight is limited to nuclear material designated to be "civilian," including plutonium and uranium used for peaceful purposes. C1 Los Alamos Natl Lab, Grp NIS 5, Los Alamos, NM 87545 USA. RP Hoida, HW (reprint author), Los Alamos Natl Lab, Grp NIS 5, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 257 EP 262 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900037 ER PT B AU Randolph, JD Pikula, M Coppinger, M Windham, M AF Randolph, JD Pikula, M Coppinger, M Windham, M GP ANS ANS TI Systems sustainability: Implementation of enhanced maintenance programs at the Kurchatov Institute, the All-Russian Research Institute of Experimental Physics (VNIIEF) and the All-Russian Scientific Institute for Technical Physics(VNIITF) SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Implementation of quality maintenance programs is essential to enhancing sustainable continuous operations of United States funded Materials Protection, Control and Accountability (MPC&A) equipment/systems upgrades at various Russian nuclear facilities. An effective maintenance program is expected to provide assurances to both parties for achieving maximum continuous systems operations with minimum down time. To be effective, the program developed must focus on minimum down time for any part of a system. Minimum down time is realized through the implementation of a quality maintenance program that includes preventative maintenance, necessary diagnostic tools, properly trained technical staff, and an in-house inventory of required spare parts for repairing the impacted component of the system. A centralized maintenance management program is logistically essential for the success of this effort because of the large volume of MPC&A equipment/systems installed at those sites. This paper will discuss current programs and conditions at the Russian Research Center-Kurchatov Institute, the All-Russian Scientific Institute for Technical Physics and the All-Russian Research Institute of Experimental Physics and will address those steps necessary to implement an upgraded program at those sites. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Randolph, JD (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 269 EP 274 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900039 ER PT B AU Wimple, C Suski, N Kreek, S Buckley, W Romine, B AF Wimple, C Suski, N Kreek, S Buckley, W Romine, B GP ANS ANS TI A future vision of nuclear material information systems SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Modern nuclear materials accounting and safeguards measurement systems are becoming increasingly advanced as they embrace emerging technologies. However, many facilities still rely on human intervention to update materials accounting records. The demand for nuclear materials safeguards information continues to increase while general industry and government downsizing has resulted in less availability of qualified staff. Future safeguards requirements will necessitate access to information through unattended and/or remote monitoring systems requiring minimal human intervention. Under the auspices of the Department of Energy (DOE), LLNL is providing assistance in the development of standards for minimum raw data file contents, methodology for comparing shipper-receiver values and generation of total propagated measurement uncertainties, as well as the implementation of modern information technology to improve reliability of and accessibility to nuclear materials information. An integrated safeguards and accounting system is described, along with data and methodology standards that ultimately speed access to this information. This system will semi-automate activities such as material balancing, reconciliation of shipper/receiver differences, and report generation. In addition, this system will implement emerging standards that utilize secure direct electronic linkages throughout several phases of safeguards accounting and reporting activities. These linkages will demonstrate integration of equipment in the facility that measures material quantities, a site-level computerized Materials Control and Accounting (MC&A) inventory system, and a country-level state system of accounting and control. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Wimple, C (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 294 EP 299 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900043 ER PT B AU Soltys, IE Yacout, AM McKnight, RD AF Soltys, IE Yacout, AM McKnight, RD GP ANS ANS TI Web interface for control of spent fuel measurements at FCF SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The material control and accountancy system for the Fuel Conditioning Facility (FCF) initially uses calculated values for the mass flows of irradiated EBR-II driver fuel to be processed in the electrorefiner. These calculated values are continually verified by measurements performed by the Analytical Laboratory (AL) on samples from the fuel element chopper retained for each chopper batch. Measured values include U and Pu masses, U and Pu isotopic fractions, and burnup (via La and Tc). When the measured data become available, it is necessary to determine if the measured and calculated data are consistent. This verification involves accessing two databases and performing standard statistical analyses to produce control charts for these measurements. These procedures can now be invoked via a Web interface providing: a timely and efficient control of these measurements, a user-friendly interface, off-site remote access to the data, and a convenient means of studying correlations among the data. This paper will present the architecture of the interface and a description of the control procedures, as well as examples of the control charts and correlations. C1 Argonne Natl Lab, Reactor Anal Div, Argonne, IL 60439 USA. RP Soltys, IE (reprint author), Argonne Natl Lab, Reactor Anal Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 300 EP 303 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900044 ER PT B AU Lenarduzzi, R Castleberry, K Whitaker, M AF Lenarduzzi, R Castleberry, K Whitaker, M GP ANS ANS TI Data collection guidelines for consistent evaluation of data from verification and monitoring safeguard systems SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB One of the several activities the International Atomic Energy Agency (IAEA) inspectors perform in the verification process of Safeguard operations is the review and correlation of data from different sources. This process is often complex due to the different forms in which the data is presented. This paper describes some of the elements that are necessary to create a 'standardized' structure for the verification of data. When properly collected and formatted, data can be analyzed with off-the shelf software applications using customized macros to automate the commands for the desired analysis. The standardized-data collection methodology is based on instrumentation guidelines as well as data structure elements, such as verifiable timing of data entry, automated data logging, identification codes, and others. The identification codes are used to associate data items with their sources and to correlate them with items from other data logging activities. The addition of predefined parameter ranges allows automated evaluation with the capability to provide a data summary, a cross-index of all data related to a specific event. Instances of actual databases are used as examples. The data collection guidelines described in this paper facilitate the use of data from a variety of instrumentation platforms and also allow the instrumentation itself to be more easily applied in subsequent monitoring applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lenarduzzi, R (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 312 EP 316 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900046 ER PT B AU Wright, MC Rome, J AF Wright, MC Rome, J GP ANS ANS TI Application of telepresence technologies to nuclear material safeguards SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB Implementation of remote monitoring systems has become a priority area for the International Atomic Energy Agency and other international inspection regimes. For the past three years, DOE2000 has been the United States Department of Energy's (DOE's) initiative to develop innovative applications to exploit the capabilities of broadband networks and media integration. The aim is to enhance scientific collaboration by merging computing and communications technologies. These Internet-based telepresence technologies could be easily extended to provide remote monitoring and control for confidence building and transparency systems at nuclear facilities around the world. One of the original DOE2000 projects, the Materials Microcharacterization Collaboratory is an interactive virtual laboratory, linking seven DOE user facilities located across the US. At these facilities, external collaborators have access to scientists, data, and instrumentation, all of which are available to varying degrees using the Internet. Remote operation of the instruments varies between passive (observational) to active (direct control), in many cases requiring no software at the remote site beyond a Web browser. Live video streams are continuously available on the Web so that participants can see what is happening at a particular location. An X.509 certificate system provides strong authentication. The hardware and software are commercially available and are easily adaptable to safeguards applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wright, MC (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6004, Oak Ridge, TN 37831 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 317 EP 323 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900047 ER PT B AU Mercer, DJ Bosler, GE Ianakiev, KD Lestone, JP Prettyman, TH Bonino, AD Grassi, E AF Mercer, DJ Bosler, GE Ianakiev, KD Lestone, JP Prettyman, TH Bonino, AD Grassi, E GP ANS ANS TI Spectroscopic verification of fuel bundles at Embalse using CdZnTe SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The Central Nuclear Embalse is a Candu-6 nuclear power station in Argentina. In support of the International Atomic Energy Agency plan to implement remote monitoring at this site, we have developed and tested a prototype underwater spent-fuel verification system based on coplanar-grid cadmium-zinc-telluride (CdZnTe) technology. The system uses the Cs-137 gamma ray signature, and is designed for minimal interference to the operator and eventual unattended operation. Test results suggest that the method is very likely to succeed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mercer, DJ (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 324 EP 330 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900048 ER PT B AU Suda, S Slovik, G Gat, U Scott, S Shumbasov, A Zhidkov, V AF Suda, S Slovik, G Gat, U Scott, S Shumbasov, A Zhidkov, V GP ANS ANS TI Bar-code based weight measurement station for physical inventory taking of plutonium oxide containers at the mining and chemical combine radiochemical reprocessing plant near Krasnoyarsk, Siberia. SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB This paper describes the technical tasks being implemented to computerize the physical inventory taking (PIT) at the Mining and Chemical Combine (Gorno-Khimichesky Kombinat, GKhK) radiochemical plant under the US/Russian cooperative nuclear material protection, control, and accounting (MPC&A) program. Under the MPC&A program, Lab-to-Lab task agreements with GKhK were negotiated that involved computerized equipment for item verification and confirmatory measurement of the Pu containers. * Tasks under Phase I cover the work for demonstrating the plan and procedures for carrying out the comparison of the Pu container identification on the container with the computerized inventory records. In addition to the records validation, the verification procedures include the application of bar codes and bar coded TIDs to the Pu containers. Phase II involves the verification of the Pu content. A plan and procedures are being written for carrying out confirmatory measurements on the Pu containers. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Suda, S (reprint author), Brookhaven Natl Lab, Bldg 197C,, Upton, NY 11973 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 333 EP 338 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900049 ER PT B AU Yacout, AM McKnight, RD Mariani, RD Westphal, B Battisti, T AF Yacout, AM McKnight, RD Mariani, RD Westphal, B Battisti, T GP ANS ANS TI MC&A sampling activities at FCF SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The electrometallurgical treatment of the Experimental Breeder Reactor-II (EBR-II) spent fuel has reached the end of its demonstration phase at the Fuel Conditioning Facility (FCF). During this phase sampling from the different material streams within the facility was important for both operational and safeguards activities. Compositions of samples are used in closeout of the different operational steps. In addition, sampling is an element of the MC&A measurement control program at the facility. It is used for inventory verification and confirmation. Errors associated with sampling are used in estimating the overall facility inventory difference uncertainty. This paper describes the MC&A related sampling activities at FCF. The MC&A sampling program is described, which include sampling at the fuel element chopper, the electrorefiner, the casting furnace and waste sampling. Also, related sampling experiments are described. Those experiments were conducted in order to determine the sampling errors associated with the estimates of fissile material in certain material streams such as the electrorefiner's Cd pool and the metal waste ingots. Implementation of sampling procedures that led to reduction in the sampling errors are also described. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Yacout, AM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 339 EP 344 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900050 ER PT B AU Strittmatter, RB Wilkey, DD Busboom, SL Ostenak, CA AF Strittmatter, RB Wilkey, DD Busboom, SL Ostenak, CA GP ANS ANS TI Proactive management of nuclear material safeguards and security at Los Alamos SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB This paper describes the strategic management of the accountability, control, and physical protection of nuclear material at Los Alamos. Changing priorities and constrained budgets across the DOE nuclear complex make performance of nuclear material safeguards and security (S&S) functions increasingly difficult. In response to new stockpile management responsibilities and a number of significant S&S issues, Los Alamos has implemented a management structure and process that defines responsibility for safeguards in all managerial levels and provides direct access to funding allocation decisions. A materials control and accounting (MC&A) Senior Steering Group was formed to prioritize and direct activities to improve S&S and to provide change control. Participation includes safeguards and program elements from both Los Alamos and the DOE/Albuquerque Operations Office, The changes allowed a prompt and organized response to identified S&S deficiencies and are intended to provide a proactive approach to managing S&S in the future. C1 Los Alamos Natl Lab, Safeguards Syst Grp NIS7, Los Alamos, NM 87545 USA. RP Strittmatter, RB (reprint author), Los Alamos Natl Lab, Safeguards Syst Grp NIS7, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 360 EP 364 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900053 ER PT B AU Rinard, PM AF Rinard, PM GP ANS ANS TI An operations-safeguards inventory verification of mixed scrap fissile materials in shipping containers SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB A verification of a large inventory of mixed scrap fissile materials in shipping containers was performed as a joint effort by personnel of the Westinghouse Savannah River Company and the Los Alamos National Laboratory. In this paper, the roles of the facility operator and the instrument developer are defined and pragmatic issues of the interaction are reviewed. The results of the verification measurements are summarized. Two instruments were used in four modes and new data analysis techniques were developed to determine plutonium and uranium masses when mixed in the same container. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rinard, PM (reprint author), Los Alamos Natl Lab, POB 1663,Mail Stop E540, Los Alamos, NM 87545 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 365 EP 369 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900054 ER PT B AU Schanfein, MJ Bruckner, LA AF Schanfein, MJ Bruckner, LA GP ANS ANS TI A practical guide to measurement control experience on non-destructive assay equipment at the Los Alamos National Laboratory Plutonium Facility SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB If you are looking for the elegant application of statistical approaches or a sophisticated analysis of a measurement control system, read no further. However, if you are interested in experiences developing, implementing, modifying, and living with a practical measurement control program for non-destructive assay equipment, please continue. This paper goes through the basis for measurement control at the Los Alamos National Laboratory (LANL) Plutonium Facility, including the philosophy, types of safeguards, accountability instruments used for quantitative assays, frequency of tests, statistics used, the link to the LANL accountability system, management structure, how measurement control works daily and monthly, common causes of failure, deficiencies, and future upgrades. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schanfein, MJ (reprint author), Los Alamos Natl Lab, POB 1663,MS E513, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 370 EP 389 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900055 ER PT B AU Burr, T Knepper, P Longmire, V AF Burr, T Knepper, P Longmire, V GP ANS ANS TI Inventory difference evaluation at the Los Alamos Plutonium Facility SO PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON FACILITY OPERATIONS-SAFEGUARDS INTERFACE LA English DT Proceedings Paper CT 6th International Conference on Facility Operations-Safeguards Interface CY SEP 20-24, 1999 CL JACKSON HOLE, WY SP Amer Nucl Soc, Inst Nucl Mat Management AB The preferred method of inventory difference (ID) evaluation is to estimate the measurement-error standard deviation of the ID using propagation of variance (POV). Historical ID evaluation can provide a useful complement to POV-based ID evaluation. Over the past few years, the Los Alamos Plutonium Facility has moved toward using both POV-based and historical ID evaluation. POV-based ID evaluation has always required more effort, primarily because of the need to model measurement error for all measurements, account for unmeasured inventory, and then perform the POV. This paper describes our effort to provide custom software to automate the routine aspects of POV-based evaluation. Specifically, we describe new software to (1) organize and access the required data and information, (2) estimate measurement-error variances, and (3) implement shortcut approximate approaches to POV using the results from (2) as inputs. We conclude with recommendations about future approaches (to what extent can POV be automated) to ID evaluation for the Plutonium Facility. C1 Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. RP Burr, T (reprint author), Los Alamos Natl Lab, Safeguards Syst Grp, POB 1663,MS E541, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PARK PA 555 N KENSINGTON AVE, LA GRANGE PARK, IL 60525 USA BN 0-89448-642-X PY 1999 BP 390 EP 397 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BT24R UT WOS:000172413900056 ER PT B AU Richards, RK Hutchinson, DP Bennett, CA Simpson, ML Liu, HC Buchanan, M AF Richards, RK Hutchinson, DP Bennett, CA Simpson, ML Liu, HC Buchanan, M BE Li, SS Liu, HC Tidrow, MZ Gunapala, SD TI Wideband heterodyne QWIP receiver development for thermonuclear fusion measurements SO PROCEEDINGS OF THE SIXTH INTERNATIONAL SYMPOSIUM ON LONG WAVELENGTH INFRARED DETECTORS AND ARRAYS: PHYSICS AND APPLICATIONS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 6th International Symposium on Long Wavelength Infrared Detectors and Arrays - Physics and Applications, at the Fall Meeting of the Electrochemical-Society CY NOV 05-06, 1998 CL BOSTON, MA SP Electrochem Soc AB Oak Ridge National Laboratory (ORNL) has been developing heterodyne receivers for plasma diagnostic applications for over 20 years. One area of this work has been the development of a diagnostic system for the measurement of the energy of alpha particles created in a thermonuclear fusion reactor These particles originate with an energy of 3.5 MeV and cool to the thermal energy of the plasma (around 15 keV) after several seconds. To measure the velocity distribution of these alpha particles, a Thomson scattering diagnostic is under development based on a high power CO2 laser at 10 microns with a heterodyne receiver. The Doppler shift generated by Thomson scattering of the alpha particles requires a wideband heterodyne receiver (greater than 10 GHz). Because Mercury-Cadimum-Telluride (MCT) detectors are limited to a bandwidth of approximately 2 GHz, a QWIP detector was obtained from the National Research Council of Canada (NRC) and evaluated for its heterodyne performance using the heterodyne testing facility developed at ORNL. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Richards, RK (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-215-X J9 ELEC SOC S PY 1999 VL 98 IS 21 BP 95 EP 100 PG 6 WC Electrochemistry; Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Electrochemistry; Engineering; Instruments & Instrumentation; Physics GA BM81T UT WOS:000079832100007 ER PT B AU Shul, RJ Zhang, L Baca, AG Han, J Crawford, MH Willison, CG Pearton, SJ Ren, F Zolper, JC Lester, LF AF Shul, RJ Zhang, L Baca, AG Han, J Crawford, MH Willison, CG Pearton, SJ Ren, F Zolper, JC Lester, LF BE Abernathy, CR Baca, A Buckley, DN Chen, KH Kopf, R Sah, RE TI High-density plasma etching of group-III nitride films for device application SO PROCEEDINGS OF THE STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS (SOTAPOCS XXX) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 30th State-of-the-Art Program on Compound Semiconductors (SOTAPOCs XXX), at the 195th Meeting of the Electrochemical-Society CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div ID LIGHT-EMITTING DIODES; INDUCTIVELY-COUPLED PLASMA; V NITRIDES; BCL3-BASED PLASMAS; GALLIUM NITRIDE; IBR/AR PLASMAS; GAN; ICL/AR; INGAN AB As m-V nitride device structures become more complicated and design rules shrink, well-controlled etch processes are necessary. Due to limited wet chemical etch results for the group-III nitrides, a significant amount of effort has been devoted to the development of dry etch processing. Dry etch development was initially focused on mesa structures where high etch rates, anisotropic profiles, smooth sidewalls, and equi-rate etching of dissimilar materials were required. For example, commercially available LEDs and laser facets for GaN-based laser diodes have been patterned using reactive ion etching (RIE). With the recent interest in high power, high temperature electronic devices, etch characteristics may also require smooth surface morphology, low plasma-induced damage, and selective etching of one layer over another. The principal criteria for any plasma etch process is its utility in the fabrication of a device. In this study, we will report plasma etch results for the group-III nitrides and their application to device structures. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shul, RJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 32 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-226-5 J9 ELEC SOC S PY 1999 VL 99 IS 4 BP 25 EP 39 PG 15 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied SC Electrochemistry; Engineering; Materials Science; Physics GA BM89P UT WOS:000080052600003 ER PT B AU Chang, PC Baca, AG Ashby, CIH Hietala, VM AF Chang, PC Baca, AG Ashby, CIH Hietala, VM BE Abernathy, CR Baca, A Buckley, DN Chen, KH Kopf, R Sah, RE TI Effect of high-voltage heterojunction bipolar transistor collector design on f(T) and f(MAX) SO PROCEEDINGS OF THE STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS (SOTAPOCS XXX) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 30th State-of-the-Art Program on Compound Semiconductors (SOTAPOCs XXX), at the 195th Meeting of the Electrochemical-Society CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div AB High-speed InGaP/GaAs heterojunction bipolar transistors (HBTs) for high-voltage circuit applications have been investigated. In order to obtain ideal IV characteristics, a lightly doped (N-DC = 7.5x10(15)cm(-3)) thick (W-C = 3.5 mu m) layer of GaAs was used as the collector layer. The devices fabricated have shown breakdown voltage exceeding 65 V. Device operatred at up to a 60V bias, which is the highest operating voltage reported up to date for single heterojunction HBTs. Peak f(T) and f(MAX) values of 18 GHz and 29 GHz, respectively, have been achieved on a device with emitter area of 4x12.5 mu m(2) Both f(T) and f(MAX) degrades with higher bias, which is related to the elongation of the collector depletion width. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chang, PC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-226-5 J9 ELEC SOC S PY 1999 VL 99 IS 4 BP 73 EP 80 PG 8 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied SC Electrochemistry; Engineering; Materials Science; Physics GA BM89P UT WOS:000080052600008 ER PT B AU Hietala, VM Baca, AG Chang, PC Sloan, LR AF Hietala, VM Baca, AG Chang, PC Sloan, LR BE Abernathy, CR Baca, A Buckley, DN Chen, KH Kopf, R Sah, RE TI Compound semiconductor devices for low-power high-efficiency Radio Frequency electronics SO PROCEEDINGS OF THE STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS (SOTAPOCS XXX) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 30th State-of-the-Art Program on Compound Semiconductors (SOTAPOCs XXX), at the 195th Meeting of the Electrochemical-Society CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div AB The power consumption of Radio Frequency (RF) electronics is a significant issue for Wireless systems. Since most wireless systems are portable and thus battery operated, reductions in DC power consumption can significantly reduce the weight and/or increase the battery lifetime of the system. As transmission consumes significantly more power than reception for most Wireless applications, previous efforts have been focused on increasing the efficiency of RF power amplification. These efforts have resulted in large increases in transmit efficiencies with research-grade amplifier efficiencies approaching 100%. In this paper, we describe our efforts on reducing power consumption of reception and other small signal RF functions. Additionally, recent power efficiency measurements on InP HEMT devices for transmission are presented. This work focuses on the needs of today's typical portable Wireless systems, which operate at frequencies up to several GHz. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hietala, VM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-226-5 J9 ELEC SOC S PY 1999 VL 99 IS 4 BP 128 EP 134 PG 7 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied SC Electrochemistry; Engineering; Materials Science; Physics GA BM89P UT WOS:000080052600015 ER PT B AU Baca, AG Chang, PC Allerman, AA Drummond, TJ AF Baca, AG Chang, PC Allerman, AA Drummond, TJ BE Abernathy, CR Baca, A Buckley, DN Chen, KH Kopf, R Sah, RE TI GaAs self-aligned JFETs with carbon-doped P+ region SO PROCEEDINGS OF THE STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS (SOTAPOCS XXX) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 30th State-of-the-Art Program on Compound Semiconductors (SOTAPOCs XXX), at the 195th Meeting of the Electrochemical-Society CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div ID GATE AB Self-aligned JFETs with a carbon-doped p(+) region have been reported for the first time. For these JFETs, both the channel and p+ region were grown by metal organic chemical vapor deposition (MOCVD) and are termed epitaxial JFETs in this study. The epitaxial JFETs were compared to ion implanted JFETs of similar channel doping and threshold voltage. Both JFETs were fabricated using the same self-aligned process for doping the source and drain regions of the JFET and for eliminating excess gate capacitance of conventional JFETs. The gate rum-on voltage for the epitaxial JFETs was 1.05 V, about 0.1 V higher than for the implanted JFETs. The reverse breakdown voltage was similar for both JFETs but the reverse gate leakage current of the epitaxial JFETs was 1-3 orders of magnitude less than the implanted JFETs. The epitaxial JFETs also showed higher transconductance and lower knee voltage than the implanted JFETs. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Baca, AG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-226-5 J9 ELEC SOC S PY 1999 VL 99 IS 4 BP 155 EP 160 PG 6 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied SC Electrochemistry; Engineering; Materials Science; Physics GA BM89P UT WOS:000080052600019 ER PT B AU Sullivan, JP Barbour, JC Dunn, RG Son, KA Montes, LP Missert, N Copeland, RG AF Sullivan, JP Barbour, JC Dunn, RG Son, KA Montes, LP Missert, N Copeland, RG BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI The electrical properties of native and deposited thin aluminum oxide layers on aluminum: Hydration effects SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA ID FILMS AB The electronic defect density of native, anodic, and synthetic Al oxide layers on Al were studied by solid state electrical measurement as a function of hydration of the oxide. The non-hydrated synthetic Al oxide layers, which included electron cyclotron resonance (ECR) plasma deposited oxides as wed as ECR plasma grown oxides, were highly insulating with electrical transport dominated by thermal emission from deep traps within the oxide. Following hydration these oxides and the native oxides exhibited a large increase in electronic defect density as evidenced by increases in the DC leakage current, reduction in the breakdown field, and increase in AC conductance. Elastic recoil detection of hydrogen revealed that hydration leads to hydrogen incorporation in the oxide films and hydrogen injection through the films into the Al layer below. The increase in electronic defect concentration is related to this hydrogenation and may play a significant role in localized corrosion initiation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sullivan, JP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 4 Z9 4 U1 1 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 111 EP 117 PG 5 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400011 ER PT B AU Jeffcoate, CS Isaacs, HS Hawkins, J Thompson, GE AF Jeffcoate, CS Isaacs, HS Hawkins, J Thompson, GE BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI The effect of chromate concentration on the repassivation of corroding aluminum SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA ID CONVERSION AB Current density maps of anodically polarized pure aluminum in chloride solutions were measured and the effect of chromate/dichromate buffer additions monitored The higher the polarized potential the more chromate was required to repassivate the corroding surface. Smalt pits repassivated easily, crevice corrosion events were the last to repassivate. Open circuit potential measurements showed the presence of meta-stable pitting at chloride concentrations of 0.3M. The lifetime and magnitude of these metastable pits was reduced on the addition of 0.05M chromate buffer. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Jeffcoate, CS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 192 EP 202 PG 5 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400018 ER PT B AU Hill, MA Bingert, JF Lillard, RS AF Hill, MA Bingert, JF Lillard, RS BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI The relationship between crystallographic orientation and the passivity and breakdown of beryllium SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA ID PITTING CORROSION AB The voltage which corresponded to the onset of pitting corrosion for S200D beryllium (Be) was found to decrease logarithmically with increasing chloride concentration according to the relationship: E-pit=-0.067log[Cl-.] - 1.01. The corrosion pits formed in Be were not hemispherical but rather the same size and shape of individual grains. In addition, parallel plates of unattacked Be could be found inside the pits indicating that pit initiation or propagation was influenced by the orientation of the grain, preliminary orientation imaging microscopy (OIM) data, which provided color contrast maps of the microtexture of polycrystalline S200D, indicated no relationship between the susceptibility of a grain to initiation and the orientation of the grain although no corrosion pits were found to initiate in the family of planes associated with the [100] direction. Potentiodynamic polarization curves for Be single crystal showed some relationship between corrosion rate and passive current density with crystal orientation. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Mat Corros & Environm Effects Lab, Los Alamos, NM 87545 USA. RP Hill, MA (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Mat Corros & Environm Effects Lab, MS G755, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 265 EP 273 PG 9 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400025 ER PT B AU Isaacs, HS Zhu, Y Sabatini, RL Ryan, MP AF Isaacs, HS Zhu, Y Sabatini, RL Ryan, MP BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI Transmission electron microscopy of undermined passive films on stainless steel SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA ID CORROSION; PITS AB A study has been made of the passive film remaining over pits on stainless steel using a high resolution transmission electron microscope. Type 305 stainless steel was passivated in a borate buffer solution and pitted in ferric chloride. Passive films formed at 0.2 V relative to a saturated calomel electrode were found to be amorphous. films formed at higher potentials showed only broad diffraction rings. The passive film was found to cover a remnant lacy structure formed over pits passivated at 0.8V. The metallic strands of the lace were roughly hemitubular in shape with the curved surface facing the center of the pit. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Isaacs, HS (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 21 TC 1 Z9 1 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 376 EP 382 PG 5 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400035 ER PT B AU Son, KA Barbour, JC Missert, N Wall, FD Copeland, RG Martinez, MA Minor, KG Buchheit, RG Isaacs, HS AF Son, KA Barbour, JC Missert, N Wall, FD Copeland, RG Martinez, MA Minor, KG Buchheit, RG Isaacs, HS BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI Pit initiation in AlOx/Al thin films SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA AB The electrochemical responses of AlOx/Al thin films have been investigated as a function of film growth conditions which produce films with different grain orientation, size and morphology. Films with smooth, 150 nm diameter, randomly oriented grains show a higher pitting potential and lower passive current than those films with large grain-boundary grooving from a mixture of smooth micron-sized, (200)-oriented grains and 300-500 nm diameter, (220)-oriented grains. These results suggest that surface roughness from grain-boundary grooving affects the pitting resistance more strongly than does the grain boundary density. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Son, KA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 673 EP 677 PG 5 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400060 ER PT B AU Wall, FD Son, KA Missert, NA Barbour, JC Martinez, MA Zavidil, KR Sullivan, JP Copeland, RG Cieslak, WR Buchheit, RG Isaacs, HS AF Wall, FD Son, KA Missert, NA Barbour, JC Martinez, MA Zavidil, KR Sullivan, JP Copeland, RG Cieslak, WR Buchheit, RG Isaacs, HS BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI The influence of nanoengineered Cu defects on aluminum fitting initiation SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA ID LOCALIZED CORROSION; PITTING CORROSION; BEHAVIOR AB Nanoengineering technologies have been used to generate well defined arrays of pure Cu islands within an Al thin film matrix in order to examine the impact of noble particle defects on the initiation of metastable pitting. The Cu particles form local galvanic cells with the surrounding Al matrix and drive metastable corrosion. Electrical isolation of the Cu particles from the At occurs due to selective Al dissolution and appears to correlate to cessation of metastable events. Distributions of parameters related to the electrochemical signature of an event suggests that size and spacing of particles do not impact the signatures of individual events. However, event frequency data indicate that the propensity for a structure to induce localized events is linked to Cu island diameter and separation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wall, FD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 701 EP 712 PG 8 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400063 ER PT B AU Zavadil, KR Barbour, JC Wall, FD Son, KA Missert, N AF Zavadil, KR Barbour, JC Wall, FD Son, KA Missert, N BE Kelley, RG Frankel, GS Natishan, PM Newman, RC TI Generation of chloride active defects at the aluminum oxide surface for the study of localized corrosion initiation SO PROCEEDINGS OF THE SYMPOSIUM ON CRITICAL FACTORS IN LOCALIZED CORROSION III: A SYMPOSIUM IN HONOR OF THE 70TH BIRTHDAY OF JEROME KRUGER SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Critical Factors in Localized Corrosion III - A Symposium in Honor of Jerome Kurgers 70th Birthday CY NOV 01, 1998 CL BOSTON, MA ID DESORPTION AB The generation of surface defects on electron cyclotron resonance (ECR) plasma derived aluminum oxide films has been studied. We find that Cl active O vacancies can be generated using electron and ion irradiation yielding surface concentrations of 3 x 10(13) to 1 x 10(14) sites cm(-2). These values correspond to surface defect concentrations of 3 to 10% when compared to ordered, crystalline alpha-alumina. The vacancies appear to be responsible for increased surface O concentrations when immersed in water. Anodic polarization of irradiated films yields a decrease in the stable pitting potential which correlates with electron dose. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Zavadil, KR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-211-7 J9 ELEC SOC S PY 1999 VL 98 IS 17 BP 713 EP 718 PG 6 WC Electrochemistry; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Electrochemistry; Materials Science; Metallurgy & Metallurgical Engineering GA BM76C UT WOS:000079705400064 ER PT B AU Richardson, TJ von Rottkay, K Slack, J Michalak, F Rubin, M AF Richardson, TJ von Rottkay, K Slack, J Michalak, F Rubin, M BE Oyama, N Birss, V TI Tungsten-vanadium oxide sputtered films for electrochromic devices SO PROCEEDINGS OF THE SYMPOSIUM ON MOLECULAR FUNCTIONS OF ELECTROACTIVE THIN FILMS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Molecular Functions of Electroactive Thin Films at the Fall Meeting of the Electrochemical-Society CY NOV 01-06, 1998 CL BOSTON, MA SP Electrochem Soc, Phys Electrochem Div ID BRONZE THIN-FILMS; OPTICAL-PROPERTIES; ABSORPTION; ELECTRODES; SYSTEMS; CELLS AB Mixed vanadium and tungsten oxide films with compositions ranging from 0 to 100% vanadium (metals basis) were prepared by reactive sputtering from metallic vanadium and tungsten targets in an atmosphere of argon and oxygen. The vanadium content varied smoothly with the fraction of total power applied to the vanadium target. Films containing vanadium were more color neutral than pure tungsten oxide films, tending to gray-brown at high V fraction. The electrochromic switching performance of these films was investigated by in situ monitoring of their visible transmittance during lithium insertion/extraction cycling in a non-aqueous electrolyte (1M LiClO4 in propylene carbonate). The solar transmittance and reflectance was measured ex situ. Films with vanadium content greater than about 15% exhibited a marked decrease in switching range. Coloration efficiencies followed a similar trend. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Richardson, TJ (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 38 TC 0 Z9 0 U1 0 U2 3 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-220-6 J9 ELEC SOC S PY 1999 VL 98 IS 26 BP 158 EP 169 PG 12 WC Chemistry, Applied; Electrochemistry; Materials Science, Coatings & Films; Polymer Science SC Chemistry; Electrochemistry; Materials Science; Polymer Science GA BN13J UT WOS:000080820700016 ER PT B AU Takano, H Porter, MD AF Takano, H Porter, MD BE Leddy, J Vanysek, P Porter, MD TI Electrochemically modulated liquid chromatography (EMLC): Manipulation of the retention of organic cations SO PROCEEDINGS OF THE SYMPOSIUM ON NEW DIRECTIONS IN ELECTROANALYTICAL CHEMISTRY II SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on New Directions in Electroanalytical Chemistry II, at the 195th Meeting of the Electrochemical-Society CY MAY 03-04, 1999 CL SEATTLE, WA SP Electrochemical Soc ID STATIONARY-PHASE; SEPARATIONS; POLYPYRROLE AB The ability of electrochemically modulated liquid chromatography (EMLC) to manipulate the retention of organic cations (i.e., various protonated anilines and pyridines) has been investigated using porous graphitic carbon (PGC) as the stationary phase. In general, the retention of these compounds increases as the applied voltage becomes more negative. This dependence is attributed to the importance of the electrostatic interactions between the charged analytes and the PGC surface. Results are also presented that demonstrate the effect of applied voltage on the separation of a mixture composed of both organic cations as well as organic anions (i.e., aromatic sulfonates). C1 US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA. RP Takano, H (reprint author), US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA. NR 15 TC 6 Z9 6 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-227-3 J9 ELEC SOC S PY 1999 VL 99 IS 5 BP 50 EP 60 PG 11 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA BN35V UT WOS:000081694900007 ER PT B AU Buettner, M Daily, W Ramirez, A Bussod, G AF Buettner, M Daily, W Ramirez, A Bussod, G BE Powers, MH Cramer, L Bell, RS TI Electrical resistance tomography of unsaturated plow and transport in Yucca Mountain SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB Electrical Resistance Tomography (ERT), a new geophysical imaging technique, was used to study the movement of a tracer through the test block at the Unsaturated Zone Transport Test (UZTT) at Busted Butte, Nevada. Data were collected four times starting in July and ending in early September, 1998. ERT baseline images show a resistivity structure which is consistent with the known lithology in the rear part of the test block. There appears to be a low resistivity region in the front half of the block, particularly near the bottom. Difference images from August 19 and September 9 show clear and consistent resistivity decreases in the region near injection holes 18, 20, and 21 which can be associated with the injection of conductive water. The images show very little effect in the region around the other injection holes, 23, and 24 through 27 where far less water was injected. Difference images from August 19 and September 9 show resistivity decreases which could be interpreted as water moving down into the block. This is the same region which has an anomalously low resistivity in the baseline image. These results should be considered preliminary, and are subject to further interpretation. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Buettner, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,7000 E Ave, Livermore, CA 94550 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 341 EP 347 PG 3 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400039 ER PT B AU Wildenschild, D Roberts, JJ Carlberg, ED AF Wildenschild, D Roberts, JJ Carlberg, ED BE Powers, MH Cramer, L Bell, RS TI Influence of microstructural properties on geophysical measurements in sand-clay mixtures SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID POROUS-MEDIA; ELECTRICAL-CONDUCTIVITY AB We have performed a series of laboratory experiments on saturated sand-clay mixtures. Measurements include frequency-dependent electrical properties using the four-electrode technique (10 mHz to 1 MHz), permeability, porosity, and acoustic velocities. We mixed clean Ottawa (quartz) sand with Na-montmorillonite (Wyoming bentonite) in a number of different configurations containing 0 to 10% clay: as a dispersed mixture, as discrete clay clusters, and arranged in distinct layers. Solutions of CaCl2 ranging from 0.0005 N to 0.75 N (0.05 to 64 mS/cm) and deionized water were used as saturating fluids. We found the electrical properties to be dependent on day content, fluid conductivity, and microstructure in a complex fashion. Increasing fluid conductivity and increasing clay content: generally resulted in higher electrical conductivity. For an individual sample, two main regions of conduction exist: a region dominated by surface conduction and a region where the ionic strength of the saturating fluid controlled conduction. The sample geometry (dispersed, nondispersed, or layered clay configuration) was found to greatly affect the magnitude of the surface conductance in the range of low fluid conductivity. C1 Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, Livermore, CA 94551 USA. RP Wildenschild, D (reprint author), Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, POB 808,L-202, Livermore, CA 94551 USA. NR 9 TC 0 Z9 0 U1 0 U2 1 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 445 EP 454 PG 4 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400050 ER PT B AU Bonner, BP Berge, P Aracne-Ruddle, C Boro, C Hardy, E Trombino, C AF Bonner, BP Berge, P Aracne-Ruddle, C Boro, C Hardy, E Trombino, C BE Powers, MH Cramer, L Bell, RS TI Ultrasonic characterization of synthetic soils for application to near surface geophysics SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID VELOCITY; SAND AB Effective seismic interrogation of the near subsurface requires that measured parameters, such as compressional and shear velocities and attenuation, be related to important soil properties. Porosity, composition (clay content), and fluid content and identification are of particular interest. The ultrasonic (100-500 kHz) pulse transmission technique was used to collect data for highly attenuating materials appropriate to the vadose zone. Up to several meters of overburden was simulated by applying low uniaxial stress of 0.1 MPa to the sample. The approach has been to make baseline measurements for pure quartz sand, because the elastic properties are relatively well known except at the lowest pressures. Second phases are then added to modify the sample microstructure and ultrasonic measurements are made to characterize the effect of the admired second phase. Samples are fabricated from Ottawa sand mixed with a swelling clay (Wyoming bentonite), and with a common organic soil amendment, peat. Compressional (P) velocities are low, ranging from 169 to 360 m/s for the mixtures at low stress. Shear (S) velocities are about half of the compressional velocity, but show different sensitivity to microstructure. Adding clay increases the shear amplitude dramatically with respect to P, and also changes the sensitivity of the velocities to load. These experiments demonstrate that P and S velocities are sensitive to the amount and type of admired second phase, even at low concentrations. Other properties of the transmitted signals which include the ratio of S and P amplitudes, velocity gradient with depth, and the frequency content of transmitted pulses, provide additional information and are not now used in near-surface surveys. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bonner, BP (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-201, Livermore, CA 94550 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 455 EP 463 PG 5 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400051 ER PT B AU Berge, PA Berryman, JG Bonner, BP Roberts, JJ Wildenschild, D AF Berge, PA Berryman, JG Bonner, BP Roberts, JJ Wildenschild, D BE Powers, MH Cramer, L Bell, RS TI Comparing geophysical measurements to theoretical estimates for soil mixtures at low pressures SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID VELOCITY; ATTENUATION; MEDIA AB Relationships between geophysical and hydrogeological properties are needed for improving characterization of the subsurface at contaminated sites using geophysical methods. As part of an on-going project with the goal of improving underground imaging, we are developing rock physics theories for relating elastic wave velocities to soil composition and fluid-flow parameters. Here we use effective medium theories to estimate velocities of unconsolidated sand-peat moss mixtures and compare the estimates to measured compressional and shear velocities from low-pressure laboratory experiments. We found that a self-consistent effective medium theory model using sand and porous peat as the constituents provides estimated velocities that are in good agreement with measured velocities. Understanding the microstructural assumptions inherent in various mixture theories guides the selection of appropriate theories for modeling velocities in soils. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Berge, PA (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-201, Livermore, CA 94550 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 465 EP 472 PG 6 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400052 ER PT B AU Newmark, RL Aines, RD Hudson, GB Leif, R Chiarappa, M Carrigan, C Nitao, JJ Elsholz, A Eaker, C AF Newmark, RL Aines, RD Hudson, GB Leif, R Chiarappa, M Carrigan, C Nitao, JJ Elsholz, A Eaker, C BE Powers, MH Cramer, L Bell, RS TI An integrated approach to monitoring a field test of in situ contaminant destruction SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB The development of in situ thermal remediation techniques requires parallel development of techniques capable of monitoring the physical and chemical changes for purposes of process control. Recent research indicates that many common contaminants can be destroyed in situ by hydrous pyrolysis/oxidation (HPO), eliminating the need for costly surface treatment and disposal. Steam injection, combined with supplemental air, can create the conditions in which HPO occurs. Field testing of this process, conducted in the summer of 1997, indicates rapid destruction of polycyclic aromatic hydrocarbons (PAHs). Previous. work established a suite of underground geophysical imaging techniques capable of providing sufficient knowledge of the physical changes in the subsurface during thermal treatment at sufficient frequencies to be used to monitor and guide the heating and extraction processes. In this field test, electrical resistance tomography (ERT) and temperature measurements provided the primary information regarding the temporal and spatial distribution of the heated zones. Verifying the in situ chemical destruction posed new challenges. We developed field methods for sampling and analyzing hot water for contaminants, oxygen, intermediates and products of reaction. Since the addition of air or oxygen to the contaminated region is a critical aspect of HPO, noble gas tracers were used to identify fluids from different sources. The combination of physical monitoring with noble gas identification of the native and injected fluids and accurate fluid sampling resulted in an excellent temporal and spatial evaluation of the subsurface processes, from which the amount of in situ destruction occurring in the treated region could be quantified. The experimental field results constrain the destruction rates throughout the site, and enable site management to make accurate estimates of total in situ destruction based on the recovered carbon. As of October, 1998, over 400,000 kg (900,000 Ib) of contaminant have been removed from the site; about 18% of this has been destroyed in situ. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Newmark, RL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 2 Z9 2 U1 0 U2 3 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 527 EP 539 PG 7 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400059 ER PT B AU Peterson, JE Majer, EL Knoll, MD AF Peterson, JE Majer, EL Knoll, MD BE Powers, MH Cramer, L Bell, RS TI Hydrogeological property estimation using tomographic data at the Boise Hydrogeophysical Research Site SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB Crosswell seismic and radar data were acquired at the Boise Hydrogeophysical Research Site (BHRS) as part of an effort to characterize the hydrological property distribution in a heterogeneous alluvial aquifer. The dielectric constant and amplitude attenuation values obtained from inversion of the radar data, as well as the seismic P-wave velocity values obtained from inversion of the seismic data, reveal similar spatial patterns. Comparison of this tomographic information with coincident wellbore logs suggest that the geophysical attributes are sensitive to hydrogeological variations. Information obtained from the radar tomography data were used to produce 2-D, high-resolution images of porosity and electrical conductivity. Comparison of these images with coincident log data reveal that these estimates are reasonable and suggests that the tomography data will be useful at this site for delineating variations in hydrological parameters. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Peterson, JE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. NR 5 TC 6 Z9 6 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 629 EP 638 PG 8 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400070 ER PT B AU Buettner, HM Berryman, JG AF Buettner, HM Berryman, JG BE Powers, MH Cramer, L Bell, RS TI An electromagnetic induction tomography field experiment at Lost Hills, CA SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID IMPEDANCE TOMOGRAPHY AB We have collected borehole to surface electromagnetic induction field data for a shallow steam injection that is underway at Mobil Oil's Lost Hills-3 field in San Joaquin Valley. Earlier work had been done at the same site by Wilt et al. (1996). This site is an interesting test for techniques under development for environmental engineering, because it can be viewed as an excellent analog of a shallow environmental remediation using steam injection. Surface magnetic field data (vertical and radial fields, magnitude and phase) were collected using 18 receiver stations along two profiles which ran radially from the EM transmitter well from 5 m to 120 m. The data at each surface station were collected while the EM transmitter was raised slowly from a depth of 120 m to a final depth of 20 m. As part of this experiment, a calibration of the EM transmitter was also performed. Magnetic field data from Lost Hills were successfully collected, including both vertical and horizontal (surface radial) magnitude and phase data along a northerly profile and along a westerly profile. We have observed that the radial receiver data appear to be better behaved than the vertical receiver data, suggesting that these data may be less sensitive to environmental clutter (numerous metallic pipes crisscrossing the site at the surface) than are the vertical data. Some simple 1-D modeling has been done to confirm that the expected conductivity change in the steam zone should produce an observable anomaly in the measured data when comparing the pre-steam to the post-steam conditions. Results of this test were positive. Further analyses of these data making use of a new code developed in a companion paper are in progress and will presented separately. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Buettner, HM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 16 TC 4 Z9 4 U1 0 U2 1 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 663 EP 672 PG 6 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400074 ER PT B AU Carle, S Ramirez, A Daily, W Newmark, R Tompson, A AF Carle, S Ramirez, A Daily, W Newmark, R Tompson, A BE Powers, MH Cramer, L Bell, RS TI High-performance computational and geostatistical experiments for testing the capabilities of 3-D electrical resistance tomography SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB This project explores the feasibility of combining geologic insight, geostatistics, and high-performance computing to analyze the capabilities of 3-D electrical resistance tomography (ERT). Geostatistical methods are used to characterize the spatial variability of geologic facies that control subsurface variability of permeability and electrical resistivity. Synthetic ERT data sets are generated from geostatistical realizations of alluvial facies architecture. The synthetic data sets enable comparison of the "truth" to inversion results, quantification of the ability to detect particular facies at particular locations, and sensitivity studies on inversion parameters. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Carle, S (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-206, Livermore, CA 94551 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 673 EP 682 PG 4 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400075 ER PT B AU Daily, W Ramirez, A AF Daily, W Ramirez, A BE Powers, MH Cramer, L Bell, RS TI Electrical imaging of engineered hydraulic barriers SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB Electrical resistance tomography (ERT) was used to image the full scale test emplacement of a thin-wall grout barrier installed by high pressure jetting. ERT was also used to monitor the water flood of a thin-wall grout barrier to veri;fy its hydraulic integrety. Both case studies were done by comparing images of electrical resistivity before and after a change was induced in the subsurface. Barrier materials or flood water were imaged as anomalies which were more electrically conducting than the native sandy soils at the test sites. Although the spatial resolution of the ERT was not sufficient to resolve flaws in the barrier under construction smaller than a reconstruction voxel (50 cm on a side), the images did show the spatial extent of the barrier materials and therefore the general shape of the structure. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Daily, W (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 683 EP 691 PG 5 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400076 ER PT B AU Ramirez, A Daily, W Binley, A LaBrecque, D AF Ramirez, A Daily, W Binley, A LaBrecque, D BE Powers, MH Cramer, L Bell, RS TI Laboratory scale tests of electrical impedance tomography SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID INDUCED-POLARIZATION DATA; RESISTIVITY TOMOGRAPHY; COMPUTED-TOMOGRAPHY; INVERSION; CONDUCTIVITIES AB Electrical impedance tomographs (magnitude and phase) of known, laboratory-scale targets are reported. Three methods are used to invert electrical impedance data and their tomographs compared. The first method uses an electrical resistance tomography (ERT) algorithm (designed for DC resistivity inversion) to perform impedance magnitude inversion and a linearized perturbation approach (PA) to invert the imaginary part. The second approximate method compares ERT magnitude inversions at two frequencies and uses the frequency effect (FE) to compute phase tomographs. The third approach, electrical impedance tomography (EIT), employs fully complex algebra to account for the real and imaginary components of electrical impedance data. The EIT approach provided useful magnitude and phase images for the frequency range of 0.0625 to 64 Hz; images for higher frequencies were not reliable. Comparisons of the ERT and EIT magnitude images show that both methods provided equivalent results for the water blank, copper rod and PVC rod targets. The EIT magnitude images showed better spatial resolution for a sand-lead mixture target. Phase images located anomalies of both high and low contrast IP and provided better spatial resolution than the magnitude images. When IP was absent from the data, the EIT algorithm reconstructed phase values consistent with the data noise levels. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ramirez, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Binley, Andrew/C-2487-2013 OI Binley, Andrew/0000-0002-0938-9070 NR 18 TC 0 Z9 0 U1 0 U2 3 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 693 EP 701 PG 5 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400077 ER PT B AU Daley, TM Peterson, JE Majer, EL AF Daley, TM Peterson, JE Majer, EL BE Powers, MH Cramer, L Bell, RS TI Simultaneous acquisition of P- and S-wave crosswell seismic profiles in a contaminated basalt aquifer SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID TEXAS CARBONATE RESERVOIR; ALGEBRAIC RECONSTRUCTION; VELOCITY AB Multiple seismic crosswell surveys have been acquired by LBNL in a fractured basalt aquifer at Idaho National Engineering and Environmental Laboratory (INEEL). Most of these surveys used a high frequency piezoelectric seismic source to obtain P-wave velocity tomograms. Additionally, we deployed a new type of borehole seismic source, know as an orbital vibrator, in a crosswell seismic survey as part of the subsurface characterization program at this contaminated groundwater site. This source, know as an orbital vibrator, allows simultaneous acquisition of P- and S-waves. The orbital vibrator was developed for oil field applications and, to our knowledge, this is the first environmental scale crosswell application. Both velocity and attenuation tomograms have been calculated. The velocity tomograms show a relationship to contaminant propagation in the groundwater las measured by logs and cores). Zones of high contaminant flow are consistent with zones of low velocity (both P- and S-wave) and high attenuation. We believe horizontal fracture zones at the boundaries of basalt flows are controlling the contaminant flow and the seismic properties. Additionally, high amplitude guided waves are observed and we believe these waves delineate thin (1-2 m) zones of velocity contrast which relate to fracturing and, in some instances, coincide with contaminate flow. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Geophys & Geomech Dept, Berkeley, CA 94720 USA. RP Daley, TM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Geophys & Geomech Dept, Berkeley, CA 94720 USA. RI Daley, Thomas/G-3274-2015 OI Daley, Thomas/0000-0001-9445-0843 NR 6 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 703 EP 712 PG 6 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400078 ER PT B AU Doll, WE Hamlett, P Smyre, J Bell, D Nyquist, JE Gamey, TJ Holladay, JS AF Doll, WE Hamlett, P Smyre, J Bell, D Nyquist, JE Gamey, TJ Holladay, JS BE Powers, MH Cramer, L Bell, RS TI A field evaluation of airborne techniques for detection of unexploded ordnance SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB United States Defense Department estimates indicate that as many as II million acres of government land in the U. S. may contain unexploded ordnance (UXO), with the cost of identifying and disposing of this material estimated at nearly $500 billion. The size and character of the ordnance, types of interference, vegetation, geology, and topography vary from site to site. Because of size or composition, some ordnance is difficult to detect with any geophysical method, even under favorable soil and cultural interference conditions. For some sites, airborne methods may provide the most time and cost effective means for detection of UXO. Airborne methods offer lower risk to field crews from proximity to unstable ordnance, and less disturbance of sites that may be environmentally sensitive. Data were acquired over a test site at Edwards AFB, CA using airborne magnetic, electromagnetic, multispectral and thermal sensors. Survey areas included sites where trenches might occur, and a test site in which we placed deactivated ordnance, ranging in size from small "bomblets" to large bombs. Magnetic data were then acquired with the Aerodat HM-3 system, which consists of three cesium magnetometers within booms extending to the front and sides of the helicopter, and mounted such that the helicopter can be flown within 3m of the surface. Electromagnetic data were acquired with an Aerodat 5 frequency coplanar induction system, deployed as a sling load from a helicopter, with a sensor altitude of 15m. Surface data, acquired at selected sites, provide a comparison with airborne data. Multispectral and thermal data were acquired with a Daedelus AADS1268 system. Preliminary analysis of the test data demonstrate the value of airborne systems for UXO detection and provide insight into improvements that might make the systems even more effective. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Doll, WE (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6038, Oak Ridge, TN 37831 USA. NR 5 TC 6 Z9 6 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 773 EP 781 PG 3 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400085 ER PT B AU Champagne, NJ Berryman, JG Buettner, HM Grant, JB Sharpe, RM AF Champagne, NJ Berryman, JG Buettner, HM Grant, JB Sharpe, RM BE Powers, MH Cramer, L Bell, RS TI A finite-difference frequency-domain code for electromagnetic induction tomography SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys ID SCATTERING; APPROXIMATION AB We are developing a new 3D code for application to electromagnetic induction tomography and to environmental imaging problems. We have used the finite-difference frequency-domain formulation of Beilenhoff et al. (1992) and the anisotropic PML (perfectly matched layer) approach (Berenger, 1994) to specify boundary conditions following Wu et al. (1997). PML deals with the fact that the computations must be done in a finite domain even though the real problem is effectively of infinite extent. The resulting formulas fdr the forward solver reduce to a problem of the form Ax = y, where A is a non-Hermitian matrix with real values off the diagonal and complex values along its diagonal. The matrix A may be either symmetric or nonsymmetric depending on details of the boundary conditions chosen (i.e., the particular PML used in the application). The basic equation must be solved for the vector x (which represents field quantities such as electric and magnetic fields) with the vector y determined by the boundary conditions and transmitter location. Of the many forward solvers that could be used for this system, relatively few have been thoroughly tested for the type of matrix encountered in our problem. Our studies of the stability characteristics of the Bi-CG algorithm raised questions about its reliability and uniform accuracy for this application. We have found the stability characteristics of Bi-CGSTAB [an alternative developed by van der Vorst (1992) for such problems] to be entirely adequate for our application, whereas the standard Bi-CG was quite inadequate. We have also done extensive validation of our code using semianalytical results as well as other codes. The new code is written in Fortran 90 and is designed to be easily parallelized, but we have not yet tested this feature of the code. An adjoint method is being developed for solving the inverse problem for conductivity imaging (for mapping underground plumes), and this approach, when ready, will make repeated use of the current forward modeling code. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Champagne, NJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 15 TC 4 Z9 7 U1 0 U2 1 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 931 EP 940 PG 4 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400102 ER PT B AU Frangos, W Weller, A Seichter, M AF Frangos, W Weller, A Seichter, M BE Powers, MH Cramer, L Bell, RS TI Three-dimensional inversion of IP data from the INEL Cold Test Pit SO PROCEEDINGS OF THE SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS LA English DT Proceedings Paper CT 12th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) at the Annual Meeting of the EEGS CY MAR 14-18, 1999 CL OAKLAND, CA SP Environm & Engn Geophys Soc, Natl Ground Water Assoc, Minerals & Geotech Logging Soc, Geo Inst Amer Soc Civil Engineers, Assoc Engn Geologists, ABEM Instrument AB, Adv Geosci Inc, Geometr, Geonics Ltd, Geophex, GSY USA Inc, Intelligent Resources, Mala Geosci USA Inc, Mt Sopris Instruments, Sensors & Software, Vanguard Geophys AB The Cold Test Pit (CTP) has been carefully constructed to simulate stored hazardous waste occurrences at the Idaho National Laboratory (INEL). An induced polarization (IP) survey of the CTP shows a very strong polarization anomaly and a modest resistivity response associated with the simulated waste. The data have been interpreted using a three-dimensional (3-D) inversion algorithm based on the simultaneous iterative reconstruction technique (SIRT) and finite difference forward modeling to form a subsurface model of complex resistivity. The edges of the waste zone are well resolved. Limited depth extent is recognized, though the bottom of the waste appears too deep. The intrinsic polarizability of the waste material has been estimated by means of a forward modeling experiment. The IP method holds promise as a technique to distinguish buried waste from pockets of conductive soil material, such as are present at the CTP. C1 Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94708 USA. RP Frangos, W (reprint author), Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94708 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1999 BP 941 EP 949 PG 3 WC Geochemistry & Geophysics; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BN80Q UT WOS:000082991400103 ER PT B AU Nilson, RH Griffiths, SK AF Nilson, RH Griffiths, SK BE Abe, T Bullis, WM Kobayashi, S Lin, W Wagner, P TI Eliminating silicon crystal defects induced by thermal and gravitational stresses SO PROCEEDINGS OF THE THIRD INTERNATIONAL SYMPOSIUM ON DEFECTS IN SILICON SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd International Symposium on Defects in Silicon, at the 195th Meeting of the Electrochemical-Society CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc ID SEMICONDUCTOR WAFERS AB Analytical models are used to optimize thermal process trajectories subject to restrictions on allowable wafer stresses and required uniformity of thermally activated processes. The maximum operating temperature is first determined by comparing calculated gravitational stresses with the temperature-dependent wafer strength. At temperatures less than this maximum, the difference between wafer strength and gravitational stress is used to determine the allowable stress and allowable temperature variation across the wafer as a function of temperature. This allowable temperature difference is then converted to an allowable ramp rate based on an analytical model of radial heat transfer in a batch furnace. Radial temperature variations predicted by this model are shown to be in good agreement with measurements made by others. Finally, these models are used to calculate optimum process trajectories and maximum batch furnace throughputs subject to prescribed thermal process uniformity. For single-wafer processors, measured temperature histories are used to construct an empirical thermal response model that can be used for stress analysis and process optimization. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Nilson, RH (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 19 TC 7 Z9 7 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-223-0 J9 ELEC SOC S PY 1999 VL 99 IS 1 BP 119 EP 132 PG 14 WC Electrochemistry; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Physics, Applied SC Electrochemistry; Materials Science; Physics GA BN35X UT WOS:000081696000010 ER PT B AU Preece, DS Chung, SH AF Preece, DS Chung, SH GP ISEE ISEE TI Modeling coal seam damage in cast blasting SO PROCEEDINGS OF THE TWENTY-FIFTH ANNUAL CONFERENCE ON EXPLOSIVES AND BLASTING TECHNIQUE, VOL II LA English DT Proceedings Paper CT 25th Annual Conference on Explosives and Blasting Technique CY FEB 07-10, 1999 CL NASHVILLE, TN SP Int Soc Explos Engineers AB A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting(Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in two dimensions (2-D). DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993b). Coal seam chilling refers to the shattering of a significant portion of the coal leaving unusable fines. It is also refered to as coal damage. Chilling is caused during a blast by a combination of explosive shock energy and movement of the adjacent rock. Chilling can be minimized by leaving a buffer zone between the bottom of the blastholes and the coal seam or by changing the blast design to decrease the powder factor or by a combination of both. Blast design in coal mine cast blasting is usually a compromise between coal damage and rock fragmentation and movement (heave). In this paper the damage to coal seams from rock movement is examined using the discrete element computer code DMC_BLAST. A rock material strength option has been incorporated into DMC_BLAST by placing bonds/links between the spherical particles used to model the rock. These bonds tie the particles together but can be broken when the tensile, compressive or shear stress in the bond exceeds the defined strength. This capability has been applied to predict coal seam damage, particularly at the toe of a cast blast where drag forces exerted by movement of the overlying rock can adversely effect the top of the coal at the bench face. A simulation of coal mine cast blasting has been performed with special attention being paid to the strength of the coal and its behavior at the bench face during movement of the overlying material. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Preece, DS (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU INT SOC EXPLOSIVES ENGINEERS PI CLEVELAND PA 29100 AURORA ROAD, CLEVELAND, OH 44139-1800 USA PY 1999 BP 233 EP 240 PG 8 WC Engineering, Civil; Engineering, Geological SC Engineering GA BQ14H UT WOS:000087294000022 ER PT B AU Dunigan, T Hinkel, G AF Dunigan, T Hinkel, G GP USENIX ASSOC USENIX ASSOC TI Intrusion detection and intrusion prevention on a large network. A case study. SO PROCEEDINGS OF THE WORKSHOP ON INTRUSION DETECTION AND NETWORK MONITORING (ID '99) LA English DT Proceedings Paper CT Workshop on Intrusion Detection and Network Monitoring (ID 99) CY APR 09-12, 1999 CL SANTA CLARA, CA SP USENIX Assoc AB This paper describes the general requirements for an Intrusion Prevention and Detection System and the methods used to prevent and detect intrusions into Oak Ridge National Laboratory's network. In this paper we describe actual intrusions, how they were detected, and how they were handled. We also describe the monitoring tools we use for detecting intrusions. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Dunigan, T (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU USENIX ASSOC PI BERKELEY PA SUITE 215, 2560 NINTH ST, BERKELEY, CA 94710 USA BN 1-880446-37-5 PY 1999 BP 11 EP 17 PG 7 WC Computer Science, Information Systems SC Computer Science GA BN01Y UT WOS:000080412900002 ER PT B AU Nastasi, M AF Nastasi, M GP OECD OECD TI The use of ion beam analysis in the synthesis of materials: A review of the determination of light elements by high-energy resonant backscattering SO PROCEEDINGS OF THE WORKSHOP ON ION AND SLOW POSITRON BEAM UTILISATION SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Ion and Slow Positron Beam Utilisation CY SEP 15-17, 1998 CL COSTA DA CAPARICA, PORTUGAL SP Org Econ Co-operat & Dev, Nucl Energy Agcy, Univ Lisboa, Ctr Fisica Nuclear, Inst Tecnol Nuclear AB The following subjects will be discussed: ion synthesis of materials and plasma immersion ion processing; - plasma immersion ion processing; Rutherford Backscatting Spectrometry (RBS); High Energy Backscattering Spectrometry (HEBS). A series of examples will also be provided. C1 Los Almos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87544 USA. RP Nastasi, M (reprint author), Los Almos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87544 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17025-1 J9 OECD PROC PY 1999 BP 131 EP 143 PG 13 WC Engineering, Biomedical; Materials Science, Multidisciplinary; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Materials Science; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA BM99T UT WOS:000080385700013 ER PT B AU Greene, SR AF Greene, SR GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI The United States reactor-based plutonium disposition programme SO PROCEEDINGS OF THE WORKSHOP ON THE PHYSICS AND FUEL PERFORMANCE OF REACTOR-BASED PLUTONIUM DISPOSITION SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on the Physics and Fuel Performance of Reactor-Based Plutonium Disposition CY SEP 28-30, 1998 CL OECD DEV CTR, PARIS, FRANCE SP OECD, Nucl Energy Agcy HO OECD DEV CTR AB The end of the Cold War has created a legacy of surplus fissile materials (plutonium and highly enriched uranium) in the US and the former Soviet Union. These materials pose a danger to national and international security. During the past few years, the US and Russia have entered into a series of agreements aimed at securing and safely storing fissile material stockpiles. Tn January 1997, the Department of Energy (DOE) announced the US would pursue a dual track approach to rendering approximately 50 metric tonnes of plutonium inaccessible for use in nuclear weapons. One track involves immobilising the plutonium by combining it with high-level radioactive waste in glass or ceramic "logs". The other method, referred to as reactor-based disposition, converts plutonium into mixed oxide (MOX) fuel for nuclear reactors. The US and Russia are moving ahead rapidly to develop and demonstrate the technology required to implement the MOX option in their respective countries. US MOX fuel research and development activities were started in the 1950s, with irradiation of MOX fuel rods in commercial light water reactors (LWR) from the 1960s-1980s. In all, a few thousand MOX fuel rods were successfully irradiated. Though much of this work was performed with weapons-grade or "near" weapons-grade plutonium - in which favourable fuel performance was observed - the applicability of this data for licensing and use of weapons-grade MOX fuel manufactured with modern fuel fabrication processes is somewhat limited. The US and Russia are currently engaged in an intensive research, development and demonstration programme (summarised in this paper) to support implementation of the MOX option in our two countries. The Organisation for Economic Go-operation and Development's (OECD) Nuclear Energy Agency (NEA) Member states can play an important role in accelerating the pace of the weapons-grade plutonium disposition campaigns in the US and in Russia. In addition to the information available in the public domain, it is important that the US and Russia have the widest possible access to relevant technical information. Both the US and Russia can learn much from the experiences of the OECD/NEA Member states who have already implemented commercial reactor-grade MOX fuel cycles. Thus, the OECD/NEA Member states have an historic opportunity to contribute in tangible ways to ridding the world of the threat posed by inventories of surplus weapons plutonium. By sharing "lessons-learned" from their commercial MOX licensing and utilisation experience, providing access to important MOX physics and fuel performance databases and by participating in essential computational benchmarking and code validation exercises, the OECD/NEA Member states can help foster a technical and regulatory environment in the US and Russia that will facilitate the safe, timely and economical implementation of the reactor-based plutonium disposition option. C1 Oak Ridge Natl Lab, Fissile Mat Disposit Program, Oak Ridge, TN 37831 USA. RP Greene, SR (reprint author), Oak Ridge Natl Lab, Fissile Mat Disposit Program, POB 2009, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 2 U2 3 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17050-2 J9 OECD PROC PY 1999 BP 25 EP 37 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20K UT WOS:000081062100002 ER PT B AU Wilson, DF DiStefano, JR Strizak, JP King, JF Manneschmidt, ET AF Wilson, DF DiStefano, JR Strizak, JP King, JF Manneschmidt, ET GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Behaviour of zircaloy cladding in the presence of gallium SO PROCEEDINGS OF THE WORKSHOP ON THE PHYSICS AND FUEL PERFORMANCE OF REACTOR-BASED PLUTONIUM DISPOSITION SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on the Physics and Fuel Performance of Reactor-Based Plutonium Disposition CY SEP 28-30, 1998 CL OECD DEV CTR, PARIS, FRANCE SP OECD, Nucl Energy Agcy HO OECD DEV CTR AB The US Department of Energy has established a dual-track approach to the disposition of plutonium arising from the dismantling of nuclear weapons. Both immobilisation and reactor-based mixed oxide (MOX) fuel technologies are being evaluated. The reactor-based MOX fuel option requires assessment of the potential impact of concentrations of gallium ton the order of 1 to 10 ppm), not present in conventional MOX fuel, on cladding material performance. An experimental programme was designed to evaluate the performance of prototypic zircaloy cladding materials against: 1) liquid gallium and 2) various concentrations of Ga2O3. Three types of tests were performed: 1) corrosion, 2) liquid metal embrittlement and 3) corrosion-mechanical. These tests were to determine corrosion mechanisms, thresholds for temperature and concentration of gallium that delineate behavioural regimes, and changes in the mechanical properties of zircaloy. Results have generally been favourable for the use of weapons-grade (WG) MOX fuel. The zircaloy cladding does react with gallium to form intermetallic compounds at greater than or equal to 300 degrees C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (parts per million) of gallium in the MOX fuel. Furthermore, no evidence for grain boundary penetration by gallium or liquid metal embrittlement was observed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wilson, DF (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 20 TC 0 Z9 0 U1 1 U2 1 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17050-2 J9 OECD PROC PY 1999 BP 169 EP 181 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BN20K UT WOS:000081062100016 ER PT B AU Gabriel, TA AF Gabriel, TA GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Status report on the spallation neutron source SO PROCEEDINGS OF THE WORKSHOP ON UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Utilisation and Reliability of High Power Proton Accelerators CY OCT 13-15, 1998 CL MITO, JAPAN SP Nucl Energy Agcy, Org Econ Cooperat & Dev AB The purpose of the Spallation Neutron Source Project (SNS) is to generate low-energy neutrons (ambient [similar to 200 meV] and cold [similar to 50 meV]) which can be used by up to 18 neutron beam lines to study the structure and functionality of materials. The neutrons are generated by the spallation process initiated by the interactions of 1 GeV protons with a Hg target. These neutrons are reflected by a Pb reflector and are moderated by two water (ambient) and two super critical hydrogen (cryogenic) moderators. The pulse structure for the 1 MW proton beam is 60 Hertz and < 0.7 mu s/pulse. The facility must be upgradable to higher power levels (2 and 4 MW) with minimal operational interruptions. Although not included in the current funding or baseline, a second target station and associated support structure which will be designed to utilise cold neutrons is also considered to be an upgrade that must be incorporated with minimal impact on operations. C1 Oak Ridge Natl Lab, Spallat Neutron Project, Oak Ridge, TN 37831 USA. RP Gabriel, TA (reprint author), Oak Ridge Natl Lab, Spallat Neutron Project, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17068-5 J9 OECD PROC PY 1999 BP 53 EP 57 PG 5 WC Nuclear Science & Technology; Physics, Nuclear SC Nuclear Science & Technology; Physics GA BN53L UT WOS:000082159000007 ER PT B AU Voit, S Venneri, F Li, N Williamson, M Houts, M Lawrence, G AF Voit, S Venneri, F Li, N Williamson, M Houts, M Lawrence, G GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Disposition of nuclear waste using subcritical accelerator driven systems SO PROCEEDINGS OF THE WORKSHOP ON UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Utilisation and Reliability of High Power Proton Accelerators CY OCT 13-15, 1998 CL MITO, JAPAN SP Nucl Energy Agcy, Org Econ Cooperat & Dev AB Los Alamos has led the development of accelerator driven transmutation of waste (ATW), to provide a fundamental technological solution to the nuclear waste problem. While ATW will not eliminate the need for a high-level waste repository, it offers a new technology option for altering the nature of nuclear waste and enhancing the capability of a repository. The basic concept of ATW focuses on reducing the time horizon for the radiological risk from hundreds of thousands of years to a few hundred years and on reducing the thermal loading. Furthermore, ATW will greatly reduce the amount of waste that has to be disposed of in a high-level waste repository. The goal of the ATW nuclear subsystem is to produce a three orders of magnitude reduction in the long-term radiotoxicity of the waste sent to a repository, including losses through processing. If the goal is met, the radiotoxicity of ATW-treated waste after 300 years would be less than that of untreated waste after 100 000 years. Through the use of high neutron fluxes produced in accelerator driven subcritical systems, these objectives can be achieved. While critical fission reactors can produce high neutron fluxes to destroy actinides and the selected fission products, the effectiveness of the destruction is severely limited by the criticality requirement. Furthermore, to achieve safe reactor operations, a substantial amount of excess reactivity would have to be supplied initially and compensated for by control poisons. To overcome these intrinsic limitations, we searched for solutions in subcritical systems freed from criticality requirement by taking advantage of the recent breakthroughs in accelerator technology and the release of liquid lead/bismuth nuclear coolant technology from Russia. The effort led to the selection of an accelerator driven subcritical system that results in near complete destruction of the actinides and fission products of concern, as well as permitting easy operational control through the external control of the neutron source rather than the internal control rods. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Voit, S (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 11 TC 0 Z9 0 U1 2 U2 3 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17068-5 J9 OECD PROC PY 1999 BP 151 EP 159 PG 9 WC Nuclear Science & Technology; Physics, Nuclear SC Nuclear Science & Technology; Physics GA BN53L UT WOS:000082159000017 ER PT B AU Cho, YL AF Cho, YL GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Reliability and availability of high power proton accelerators SO PROCEEDINGS OF THE WORKSHOP ON UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Utilisation and Reliability of High Power Proton Accelerators CY OCT 13-15, 1998 CL MITO, JAPAN SP Nucl Energy Agcy, Org Econ Cooperat & Dev AB It has become increasingly important to address the issues of operational reliability and availability of an accelerator complex early in its design and construction phases. In this context, reliability addresses the mean time between failures and the failure rate, and availability takes into account the failure rate as well as the length of time required to repair the failure. Methods to reduce failure rates include reduction of the number of components and over-design of certain key components. Reduction of the on-line repair time can be achieved by judiciously designed hardware, quick-service spare systems and redundancy. In addition, provisions for easy inspection and maintainability are important for both reduction of the failure rate as well as reduction of the time to repair. The radiation safety exposure principle of ALARA (as low as reasonably achievable) is easier to comply with when easy inspection capability and easy maintainability are incorporated into the design. Discussions of past experience in improving accelerator availability, some recent developments, and potential R&D items are presented. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Cho, YL (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17068-5 J9 OECD PROC PY 1999 BP 227 EP 237 PG 11 WC Nuclear Science & Technology; Physics, Nuclear SC Nuclear Science & Technology; Physics GA BN53L UT WOS:000082159000023 ER PT B AU Voit, S AF Voit, S GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Thermomechanical analysis of an ATW fuel element under an accident scenario SO PROCEEDINGS OF THE WORKSHOP ON UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Utilisation and Reliability of High Power Proton Accelerators CY OCT 13-15, 1998 CL MITO, JAPAN SP Nucl Energy Agcy, Org Econ Cooperat & Dev AB The integrity a fuel element in the ATW system is being evaluated under an accident scenario in which the accelerator is ramped to full power instantaneously creating a hyperbolic tangent neutron flux profile. Under this scenario, severe thermal transients will arise in the fuel and the fission heating of the fuel will occur faster than thermal strains can be relieved by material deformation. The thermal shock will produce vibrations leading to high stresses in the fuel and supporting structure. This analysis may have additional implications with regard to the effects on accelerator trip events on the integrity of the ATW reactor system. ABAQUS, a transient-dynamic finite element code, is being used to determine the time dependent stresses and displacements due to thermal shock loads. A normalised measure of stress (NS) is being evaluated at a time when the peak tensile strength is reached. The normalised measure of stress is the ratio of the von Mises (effective) stress to the temperature dependent tensile strength in each finite element. NS values of greater than one indicate that the tensile strength has been exceeded and that failure is expected. Because of the preliminary stage of the investigation, many physical details such as the mechanical interaction of the expanded fuel and the cladding, which would affect the thermomechanical behaviour of the fuel elements, are neglected. Parametric studies are being conducted in which the temperature rise parameters, fuel dimensions, and material assumptions are varied. Further analyses will include sensitivity studies to determine the optimum fuel design and driver ramp-up protocol to ensure that the fuel matrix will remain in the elastic or near-elastic range. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Voit, S (reprint author), Univ Calif Los Alamos Natl Lab, Box 1663 K575, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17068-5 J9 OECD PROC PY 1999 BP 343 EP 344 PG 2 WC Nuclear Science & Technology; Physics, Nuclear SC Nuclear Science & Technology; Physics GA BN53L UT WOS:000082159000033 ER PT B AU Takahashi, H Rugierro, A Zhao, Y Tsoupas, N AF Takahashi, H Rugierro, A Zhao, Y Tsoupas, N GP ORG ECON COOPERAT & DEV ORG ECON COOPERAT & DEV TI Requirements of accelerators for accelerator driven reactor SO PROCEEDINGS OF THE WORKSHOP ON UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS SE OECD PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Utilisation and Reliability of High Power Proton Accelerators CY OCT 13-15, 1998 CL MITO, JAPAN SP Nucl Energy Agcy, Org Econ Cooperat & Dev AB The reliability of accelerators for industrial use such as energy production or transmutation of radioactive material can be extensively increased by taking into account the safety factor of reducing the electric field strength for acceleration cavity. To keep energy cost low, the accelerator should be in hand on maintenance by minimising the beam loss. The two methods of spreading proton beam are described. Although the CW beam is most favourable for accelerator driven reactor, the use of pulsed spallation neutron for this ADR such as the induction linac and fixed field alternating gradient accelerator (FFAG) are discussed with the fatigue problem of the solid fuel due to periodic shock by the pulsed operation of accelerator. The control of reactor power by neutron absorber is discussed in comparison with the approach used by accelerator power, and the non-proliferation problem is mentioned for accelerators. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Takahashi, H (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-17068-5 J9 OECD PROC PY 1999 BP 345 EP 354 PG 10 WC Nuclear Science & Technology; Physics, Nuclear SC Nuclear Science & Technology; Physics GA BN53L UT WOS:000082159000034 ER PT S AU Lindsey, RP Barnes, JL AF Lindsey, RP Barnes, JL BE Marcus, MA Wang, A TI Sensitive oil industry: users of advanced technology SO PROCESS MONITORING WITH OPTICAL FIBERS AND HARSH ENVIRONMENT SENSORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Process Monitoring with Optical Fibers and Harsh Environment Sensors CY NOV 03-04, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers DE petroleum sensors; microtools; downhole environment; backscatter absorption gas imaging AB The oil industry exemplifies mankind's search for resources in a harsh environment hereon the earth. Traditionally the oil industry has created technological solutions to increasingly difficult exploration, drilling, and production activities as the need has arisen. The depths to which a well must be drilled to produce the finite hydrocarbon resources are increasing and the surface environments are becoming increasingly sensitive to human activity. information about the downhole environment during oil and gas activities is the key to success, not information that is hours old or incomplete; but "real-time" data that responds to the variable environment downhole and allows prediction and prevention. The difference that information makes can be the difference between a successfully drilled well and a blowout that causes permanent damage to the reservoir and may reduce the value of the reserves downhole. The difference that information makes can the difference between recovering 22% of the hydrocarbon reserves in a profitable field and recovering none of the reserves because of an uneconomic bottom line. Sensors of every type are essential in the new oil and gas industry and they must be rugged accurate, affordable, and long lived. It is not just for the sophisticated majors exploring the very deep waters of the world but for the thousands of independent producers who provide a lion's share of the oil and gas produced in the United States domestic market. The Department of Energy has been instrumental in keeping reserves from being lost by funding advancements in sensor technology. Due to sponsorship by the Federal Government, the combined efforts of researchers in the National Laboratories, academic institutions, and industry research centers are producing increasingly accurate tools capable of functioning in extreme conditions with economics acceptable to the accountants of the industry. Three examples of such sensors developed with Federal funding are given. C1 US DOE, Natl Petr Technol Off, Tulsa, OK 74101 USA. RP Lindsey, RP (reprint author), US DOE, Natl Petr Technol Off, POB 3628, Tulsa, OK 74101 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2999-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3538 BP 4 EP 9 DI 10.1117/12.335731 PG 6 WC Engineering, Chemical; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BM42V UT WOS:000078691200001 ER PT S AU Woodruff, SD AF Woodruff, SD BE Marcus, MA Wang, A TI Optical diagnostics in gas turbine combustors SO PROCESS MONITORING WITH OPTICAL FIBERS AND HARSH ENVIRONMENT SENSORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Process Monitoring with Optical Fibers and Harsh Environment Sensors CY NOV 03-04, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers DE Combustion; imaging; hydroxyl (OH); diagnostics AB Deregulation of the power industry and increasingly tight emission controls are pushing gas turbine manufacturers to develop engines operating at high pressure for efficiency and lean fuel mixtures to control NOx. This combination also gives rise to combustion instabilities which threaten engine integrity through acoustic pressure oscillations and flashback. High speed imaging and OH emission sensors have been demonstrated to be invaluable tools in characterizing and monitoring unstable combustion processes. Asynchronous imaging techniques permit detailed viewing of cyclic flame structure in an acoustic environment which may be modeled or utilized in burner design. The response of the flame front to the acoustic pressure cycle may be tracked with an OH emission monitor using a sapphire light pipe for optical access. The OH optical emission can be correlated to pressure sensor data for better understanding of the acoustical coupling of the flame. Active control of the combustion cycle can be implemented using an OH emission sensor for feedback. C1 US DOE, Fed Energy Technol Ctr, Morgantown, WV 26507 USA. RP Woodruff, SD (reprint author), US DOE, Fed Energy Technol Ctr, Morgantown, WV 26507 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2999-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3538 BP 92 EP 98 DI 10.1117/12.335733 PG 7 WC Engineering, Chemical; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BM42V UT WOS:000078691200011 ER PT B AU Embury, JD Han, K AF Embury, JD Han, K BE Ellyin, F Provan, JW TI Dislocation accumulation at large plastic strains - An approach to the theoretical strength of materials. SO PROGRESS IN MECHANICAL BEHAVIOUR OF MATERIALS (ICM8), VOL 2: MATERIAL PROPERTIES LA English DT Proceedings Paper CT 8th International Conference on the Mechanical Behaviour of Materials (ICM8) CY MAY 16-21, 1999 CL VICTORIA CONF CTR, VICTORIA, CANADA SP ICM Board Governors HO VICTORIA CONF CTR ID PEARLITIC STEEL WIRES; HEAVILY COLD DRAWN; COMPOSITES; MICROSTRUCTURE; DEFORMATION; FIELDS; CREEP; FLOW C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Embury, JD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 42 TC 0 Z9 0 U1 1 U2 1 PU UNIV VICTORIA, DEPT MECH ENGN PI VICTORIA PA VICTORIA, BC V8W 3P6, CANADA BN 1-55058-164-3 PY 1999 BP 448 EP 457 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BQ77E UT WOS:000089495500001 ER PT J AU Nigg, DW AF Nigg, DW TI Some recent trends and progress in the physics and biophysics of neutron capture therapy SO PROGRESS IN NUCLEAR ENERGY LA English DT Article DE BNCT; boron; neutron; cancer; glioma; reactors; accelerators; dosimetry ID IRRADIATION FACILITY; RADIOTHERAPY; DESIGN; CHEMISTRY; CANCER; BEAMS; BNCT AB Building upon earlier American efforts in the field as well as upon continuing research in Japan, clinical trials of epithermal-neutron boron neutron capture therapy (BNCT) for glioblastoma multiforme and for malignant melanoma began in the U.S. in 1994 and in Europe in 1997. These trials, while not yet conclusive, are showing promise and have stimulated the development of improved reactor-based epithermal-neutron beam facilities as well as several types of accelerator-based neutron sources for future trials of this modality worldwide. Developments in computational dosimetry and treatment planning techniques and software suitable for BNCT applications have also continued apace. Interest in various applications of neutron capture techniques to other malignancies as well as to some non-malignant conditions such as rheumatoid arthritis is also accelerating, (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Nigg, DW (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 96 TC 17 Z9 17 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 1999 VL 35 IS 1 BP 79 EP 127 DI 10.1016/S0149-1970(99)00004-9 PG 49 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 194UF UT WOS:000080211500003 ER PT J AU Spriggs, GD Sakurai, T Okajima, S AF Spriggs, GD Sakurai, T Okajima, S TI Rossi-alpha and beta(eff) measurements in a fast critical assembly SO PROGRESS IN NUCLEAR ENERGY LA English DT Article AB An experiment was performed to measure rile effective delayed neutron fraction of a zero-power reactor (designated as rile XIX-1 assembly,) at the Fast Critical Assembly (FCA) facility operated by rile Japan Atomic Energy Research Institute (JAERI). The measurements were perfomed using a Rossi-alpha technique known as the Nelson Number method. Ir was found that rile effective delayed neutron fraction was 737 +/- 20 pcm. (C) 1999 Published by Elsevier Science Ltd. all rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Japan Atom Energy Res Inst, Oarai, Ibaraki 31911, Japan. RP Spriggs, GD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS F664, Los Alamos, NM 87545 USA. NR 4 TC 2 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 1999 VL 35 IS 2 BP 169 EP 181 DI 10.1016/S0149-1970(99)00010-4 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 252ZZ UT WOS:000083533300005 ER PT J AU Uhrig, RE Tsoukalas, LH AF Uhrig, RE Tsoukalas, LH TI Soft computing technologies in nuclear engineering applications SO PROGRESS IN NUCLEAR ENERGY LA English DT Article DE neural networks; fuzzy logic; genetic algorithms; soft computing; nuclear power; diagnostics; system modeling ID ARTIFICIAL NEURAL-NETWORK; MODERATOR TEMPERATURE-COEFFICIENT; PRESSURIZED-WATER-REACTORS; GENETIC ALGORITHMS; PLANT; VALIDATION; SYSTEM AB The application of soft computing technologies, particularly neural networks, fuzzy logic, and genetic algorithms, to the surveillance, diagnostics and operation of nuclear power plants and their components is an area that has great potential for exploitation. Areas of potential application are to the surveillance and diagnostics of complete nuclear power plants and to specific systems such as check valves, instrumentation systems, and rotating machinery. Applications include sensor surveillance and calibration verification, diagnostics of both plant transients and specific faults, efficiency optimization, vibration analysis, loose parts monitoring, and adaptive and/or optimal control. The synergistic benefits of combining the use of neural networks, fuzzy systems and genetic algorithms are illustrated in several application. Although some of the work cited (e.g. vibration systems) are not necessarily associated with nuclear power plants, the results are directly applicable. Indeed, the methodologies of soft computing technologies have many applications outside the nuclear power field, e.g., fossil-fired power plants, chemical process facilities, high performance aerospace systems, financial market issues, sociological systems, and others. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Knoxville, TN 37996 USA. Purdue Univ, W Lafayette, IN 47907 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Uhrig, RE (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. NR 87 TC 33 Z9 36 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 1999 VL 34 IS 1 BP 13 EP 75 DI 10.1016/S0149-1970(97)00109-1 PG 63 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 141BX UT WOS:000077123700002 ER PT J AU Durkee, JW Streetman, JR Sapir, JL Andrade, A AF Durkee, JW Streetman, JR Sapir, JL Andrade, A TI 3-D Monte Carlo and discrete ordinates void coefficient analysis for the Los Alamos National Laboratory Omega West reactor using MCNP and THREEDANT SO PROGRESS IN NUCLEAR ENERGY LA English DT Article AB Three-dimensional Monte Carlo and discrete ordinates computational modeling techniques have been used to characterize void coefficient behavior for three experimental channels and several fuel assemblies in the Los Alamos Omega West nuclear reactor using MCNP and THREEDANT. Good agreement is observed in void coefficient behavior predicted by MCNP and THREEDANT. The experimental-channel gross-voiding calculations predict the existence of positive void coefficients due to overmoderation conditions. The fuel assemblies exhibit, for the most part, negative void coefficients, although the possibility of localized small positive void coefficients for one of the five assemblies analyzed is indicated. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Reactor Design & Anal Grp TSA12, Los Alamos, NM 87545 USA. RP Durkee, JW (reprint author), Univ Calif Los Alamos Natl Lab, Reactor Design & Anal Grp TSA12, POB 1663, Los Alamos, NM 87545 USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 1999 VL 34 IS 2 BP 99 EP 142 DI 10.1016/S0149-1970(97)00001-2 PG 44 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 141BY UT WOS:000077123800001 ER PT J AU Auerbach, T Michael, P Rothenstein, W Srikantiah, G Takahashi, H AF Auerbach, T Michael, P Rothenstein, W Srikantiah, G Takahashi, H TI Reminiscences from the Reactor Theory Group at Brookhaven National Laboratory SO PROGRESS IN NUCLEAR ENERGY LA English DT Editorial Material C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Technion Israel Inst Technol, Fac Mech Engn, IL-32000 Haifa, Israel. Elect Power Res Inst, Energy Convers Div, Palo Alto, CA 94303 USA. RP Auerbach, T (reprint author), Staldenstr 7, CH-5412 Gebenstorf, Switzerland. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 1999 VL 34 IS 4 BP 313 EP 335 DI 10.1016/S0149-1970(98)00014-6 PG 23 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 173DT UT WOS:000078966500002 ER PT J AU McFarlane, KF Lineberry, MJ AF McFarlane, KF Lineberry, MJ TI An insiders' perspective of fast reactor technology SO PROGRESS IN NUCLEAR ENERGY LA English DT Article C1 Argonne Natl Lab, Idaho Falls, ID 83403 USA. RP McFarlane, KF (reprint author), Argonne Natl Lab, POB 2528, Idaho Falls, ID 83403 USA. NR 27 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 1999 VL 34 IS 4 BP 453 EP 469 DI 10.1016/S0149-1970(98)00023-7 PG 17 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 173DT UT WOS:000078966500011 ER PT S AU Kahana, DE Kahana, SH AF Kahana, DE Kahana, SH BE Faessler, A TI J/psi suppression in heavy ion collisions at the CERN SPS SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 42: HEAVY ION COLLISIONS FROM NUCLEAR TO QUARK MATTER SE Progress in Particle and Nuclear Physics LA English DT Article; Proceedings Paper CT Erice School on Heavy Ion Collisions from Nuclear to Quark Matter CY SEP 17-25, 1998 CL ERICE, ITALY ID NUCLEUS-NUCLEUS COLLISIONS; GEV-C; PARTICLE; HADRON AB We reexamine the production of J/psi, and other charmonium states for a variety of target-projectile choices at the SPS, in particular for the interesting comparison between S+U at 200 GeV/c and Pb+Pb at 158 GeV/c as observed in the experiments NA38 and NA50 respectively. The result is a description of the NA38 and NA50 data in terms of a conventional, quasi-hadronic picture. The apparently anomalous suppression found in the most massive Pb+Pb system arises in the present simulation from three sources: destruction in the initial nucleon-nucleon cascade phase, use of coupled channels to exploit the larger breakup in the less bound chi(i) and psi' states, and comover interaction in the final low energy phase. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP 31 Pembrook Dr, Stony Brook, NY 11790 USA. OI Kahana, David Ewan/0000-0003-1266-9089 NR 31 TC 19 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 BN 0-444-50246-7 J9 PROG PART NUCL PHYS PY 1999 VL 42 BP 269 EP 278 DI 10.1016/S0146-6410(99)00082-4 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN11T UT WOS:000080760400028 ER PT S AU Bass, SA Weber, H Ernst, C Bleicher, M Belkacem, M Bravina, L Soff, S Stocker, H Greiner, W Spieles, C AF Bass, SA Weber, H Ernst, C Bleicher, M Belkacem, M Bravina, L Soff, S Stocker, H Greiner, W Spieles, C BE Faessler, A TI Reaction dynamics in Pb plus Pb at the CERN/SPS: From partonic degrees of freedom to freeze-out SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 42: HEAVY ION COLLISIONS FORM NUCLEAR TO QUARK MATTER SE PROGRESS IN PARTICLE AND NUCLEAR PHYSICS LA English DT Article; Proceedings Paper CT Erice School on Heavy Ion Collisions form Nuclear to QuarK Matter CY SEP 17-25, 1998 CL ERICE, ITALY ID RELATIVISTIC NUCLEAR COLLISIONS; HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; SUPERDENSE MATTER; EQUATION; STATE; QCD; CASCADES AB We analyze the reaction dynamics of central Pb+Pb collisions at 160 GeV/nucleon. First we estimate the energy density epsilon pile-up at mid-rapidity and calculate its excitation function: epsilon is decomposed into hadronic and partonic contributions. A detailed analysis of the collision dynamics in the framework of a microscopic transport model shows the importance of partonic degrees of freedom and rescattering of leading (di)quarks in the early phase of the reaction for E-lab greater than or equal to 30 GeV/nucleon. The energy density reaches up to 4 GeV/fm(3), 95% of which are contained in partonic degrees of freedom. It is shown that cells of hadronic matter, after t approximate to 2R/gamma upsilon(cm), can be viewed as nearly chemically equilibrated. This matter never exceeds energy densities of similar to 04 GeV/fm(3), i.e. a density above which the notion of separated hadrons loses its meaning. The final reaction stage is analyzed in terms of hadron ratios, freeze-out distributions and a source analysis for final state pions. C1 Duke Univ, Dept Phys, Durham, NC 27708 USA. Univ Frankfurt, Inst Theoret Phys, D-60054 Frankfurt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bass, SA (reprint author), Duke Univ, Dept Phys, Durham, NC 27708 USA. RI Bleicher, Marcus/A-2758-2010; Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 31 TC 15 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE PUBL B V PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 BN 0-444-50246-7 J9 PROG PART NUCL PHYS PY 1999 VL 42 BP 313 EP 322 DI 10.1016/S0146-6410(99)00086-1 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BN11T UT WOS:000080760400032 ER PT J AU Thomas, MG Post, HN DeBlasio, R AF Thomas, MG Post, HN DeBlasio, R TI Photovoltaic systems: An end-of-millennium review SO PROGRESS IN PHOTOVOLTAICS LA English DT Review AB The production of electricity from photovoltaics continues to attract worldwide interest, most recently as a power source for distributed energy generation. Today's photovoltaic systems are already being used effectively for smaller power needs in remote applications. For both of these applications, the issues of reliability, efficiency, safety, and low cost are the principal drivers of system technology. This review used these design issues to provide a system perspective on the current status of the technology, the change it has already experienced and the necessity for improvements, especially in tomorrow's systems. The discussion of remaining issues focuses on the reduction of area-related and collector costs, the accurate prediction of performance and lifetime, and the need for developing much better information on recurring costs for maintenance and component replacement. Copyright (C) 1999 John Wiley & Sons, Ltd. This paper was produced under the auspices of the US government and it is therefore not subject to copyright in the US. C1 Sandia Natl Labs, PV Syst Dept, Natl Ctr Photovoltaics, Albuquerque, NM 87185 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Post, HN (reprint author), Sandia Natl Labs, PV Syst Dept, Natl Ctr Photovoltaics, POB 5800, Albuquerque, NM 87185 USA. EM hnpost@sandia.gov NR 25 TC 33 Z9 33 U1 1 U2 8 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD JAN-FEB PY 1999 VL 7 IS 1 BP 1 EP 19 PG 19 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 194NE UT WOS:000080199800001 ER PT J AU Green, MA Emery, K Bucher, K King, DL Igari, S AF Green, MA Emery, K Bucher, K King, DL Igari, S TI Solar cell efficiency tables (version 13) SO PROGRESS IN PHOTOVOLTAICS LA English DT Article ID PERFORMANCE AB Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 1998 are briefly described. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Univ New S Wales, Photovoltaics Special Res Ctr, Sydney, NSW 2052, Australia. Natl Renewable Energy Lab, Golden, CO 80401 USA. Fraunhofer Inst Solar Energy Syst, D-79100 Freiburg, Germany. Sandia Natl Labs, Div 6224, Albuquerque, NM 87185 USA. Japan Qual Assurance Org, Solar Techno Ctr, Solar Cell Test Res Div, Hamamatsu, Shizuoka 43112, Japan. RP Green, MA (reprint author), Univ New S Wales, Photovoltaics Special Res Ctr, Sydney, NSW 2052, Australia. NR 51 TC 16 Z9 16 U1 3 U2 11 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD JAN-FEB PY 1999 VL 7 IS 1 BP 31 EP 37 PG 7 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 194NE UT WOS:000080199800003 ER PT J AU Ooguri, H AF Ooguri, H TI Wilson loops and minimum surfaces SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article; Proceedings Paper CT 13th Nishinomiya Yukawa Memorial Symposium CY NOV 12-13, 1998 CL NISHINOMIYA, JAPAN AB The AdS/CFT correspondence suggests that the Wilson loop of the large N gauge theory with N = 4 supersymmetry in 4 dimensions is described by a minimal surface in AdS(5) x S-5. We examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Ooguri, Hirosi/A-4407-2011; OI Ooguri, Hirosi/0000-0001-6021-3778 NR 12 TC 0 Z9 0 U1 0 U2 0 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 1999 IS 134 BP 153 EP 157 PG 5 GA 223PD UT WOS:000081848700008 ER PT J AU Zachos, C Curtright, T AF Zachos, C Curtright, T TI Phase-space quantization of field theory SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article; Proceedings Paper CT Workshop on Gauge Theory and Integrable Models CY JAN 26-29, 1999 CL KYOTO UNIV, YUKAWA INST THEORET PHYS, KYOTO, JAPAN SP Univ Kyoto, Yukawa Inst Theoret Phys HO KYOTO UNIV, YUKAWA INST THEORET PHYS ID DEFORMATION THEORY; QUANTUM-MECHANICS; FORMULATION; ALGEBRA AB In this lecture, a limited introduction of gauge invariance in phase-space is provided, predicated on canonical transformations in quantum phase-space. Exact characteristic trajectories are also specified for the time-propagating Wigner phase-space distribution function: they are especially simple - indeed, classical - for the quantized simple harmonic oscillator. This serves as the underpinning of the field theoretic Wigner functional formulation introduced. Scalar field theory is thus reformulated in terms of distributions in field phase-space. This is a pedagogical selection from work published in Refs. 1) and 2). C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Miami, Dept Phys, Coral Gables, FL 33124 USA. RP Zachos, C (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. RI zachos, cosmas/C-4366-2014; Curtright, Thomas/B-6840-2015; OI zachos, cosmas/0000-0003-4379-3875; Curtright, Thomas/0000-0001-7031-5604 NR 45 TC 19 Z9 19 U1 0 U2 0 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 1999 IS 135 BP 244 EP 258 PG 15 GA 245WH UT WOS:000083130800018 ER PT S AU Nelson, DH Petrin, RR Quick, CR Jolin, LJ MacKerrow, EP Schmitt, MJ Foy, BR Koskelo, AC McVey, BD Porch, WM Tiee, JJ Fite, CB Archuleta, FK Whitehead, MC Walters, DL AF Nelson, DH Petrin, RR Quick, CR Jolin, LJ MacKerrow, EP Schmitt, MJ Foy, BR Koskelo, AC McVey, BD Porch, WM Tiee, JJ Fite, CB Archuleta, FK Whitehead, MC Walters, DL BE Roggemann, MC Bissonnette, LR TI Huygens-Fresnel wave-optics simulation of atmospheric optical turbulence and reflective speckle in CO2 differential absorption lidar (DIAL) SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Propagation and Imaging through the Atmosphere III CY JUL 22-23, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE atmospheric turbulence; laser speckle; beam propagation ID PHASE-SCREEN; RANDOM-MEDIA; STATISTICS; INTENSITY AB The measurement sensitivity of CO2 differential absorption LIDAR (DIAL) can be affected by a number of different processes. Two of these processes are atmospheric optical turbulence and reflective speckle. Atmospheric optical turbulence affects the beam distribution of energy and phase on target. The effects of this phenomenon include beam spreading, beam wander and scintillation which can result in increased shot-to-shot signal noise. In addition, reflective speckle alone has been shown to have a major impact on the sensitivity of CO2 DIAL. We have previously developed a Huygens-Fresnel wave optics propagation code to separately simulate the effects of these two processes. However, in real DIAL systems it is a combination of these phenomena, the interaction of atmospheric optical turbulence and reflective speckle, that influences the results. In this work we briefly review a description of our model including the limitations along with a brief summary of previous simulations of individual effects. The performance of our modified code with respect to experimental measurements affected by atmospheric optical turbulence and reflective speckle is examined. The results of computer simulations are directly compared with lidar measurements and show good agreement. In addition, simulation studies have been performed to demonstrate the utility and limitations of our model. Examples presented include assessing the effects for different army sizes on model limitations and effects of varying propagation step sizes on intensity enhancements and intensity probability distributions in the receiver plane. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Nelson, DH (reprint author), Univ Calif Los Alamos Natl Lab, MS E543, Los Alamos, NM 87545 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3249-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3763 BP 218 EP 229 DI 10.1117/12.363616 PG 12 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BN95F UT WOS:000083637500022 ER PT J AU Idar, DI Asay, BW Ferm, EN AF Idar, DI Asay, BW Ferm, EN TI Improved characterization of nitromethane, nitromethane mixtures, and shaped-charge jet properties SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article AB An extensive study of the initiation of nitromethane by shaped-charge jets has been conducted and is reported in the paper following this one. In order to accomplish this a great deal of background information and description of the effect of temperature on failure diameter, measurement of jet diameters, material properties and experimental configuration is necessary. The collection of these data is of general interest to the field of energetic materials research, and is presented here as a separate paper. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Idar, DI (reprint author), Univ Calif Los Alamos Natl Lab, MSC920, Los Alamos, NM 87545 USA. NR 14 TC 2 Z9 2 U1 0 U2 2 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD JAN PY 1999 VL 24 IS 1 BP 1 EP 6 DI 10.1002/(SICI)1521-4087(199902)24:1<01::AID-PREP1>3.0.CO;2-L PG 6 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 190LM UT WOS:000079964600001 ER PT J AU Idar, DJ Asay, BW Ferm, EN AF Idar, DJ Asay, BW Ferm, EN TI Hypervelocity jet initiation threshold criteria of nitromethane and nitromethane mixtures SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article ID DETONATION AB The experimental hypervelocity jet initiation threshold criteria for neat nitromethane and homogeneous- and heterogeneous-sensitized nitromethane mixtures have been determined over a range of failure diameters, jet velocities from 2-9 mm/mu s, and jet diameters In two test configurations. These criteria were used to define detonation and failure conditions in nitromethane and the nitromethane mixtures as a function of contact- and bow-shock conditions. These data were compared with data reported by others in the literature on bare solid explosives. A favorable comparison of threshold values is achieved by normalization of the criteria with the failure diameters. The effect on the initiation of the confinement proximity to the jet axis was also investigated. Experimental results have shown that high impedance boundaries near the jet axis induced conditions that allowed initiation to occur at lower jet velocities than those determined by the criteria. Tests also were performed on both homogeneous and heterogeneous nitromethane mixtures, having the same failure diameters, to determine if the same or similar jet penetration distances were required for initiation. The results, within experimental error, do not show any definitive differences in initiation conditions between the two types of mixtures. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Idar, DJ (reprint author), Univ Calif Los Alamos Natl Lab, MS C920, Los Alamos, NM 87545 USA. NR 31 TC 2 Z9 2 U1 0 U2 1 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD JAN PY 1999 VL 24 IS 1 BP 7 EP 16 DI 10.1002/(SICI)1521-4087(199902)24:1<07::AID-PREP7>3.0.CO;2-Y PG 10 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 190LM UT WOS:000079964600002 ER PT S AU Martin, PM Johnston, JW Bennett, WD AF Martin, PM Johnston, JW Bennett, WD BE Johnson, RN Lee, WY Pickering, MA Sheldon, BW TI Multilayer coatings and optical materials for tuned infrared emittance and thermal control SO PROPERTIES AND PROCESSING OF VAPOR-DEPOSITED COATINGS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Properties and Processing of Vapor-Deposited Coatings, at the 1998 MRS Fall Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB Many thermal control applications require thin film coatings that emit or absorb strongly at near infrared and infrared wavelengths. One of the primary applications for these coatings is thermal control for surfaces and structures of spacecraft, which are exposed to solar radiation during at least 60% of their orbit, causing wide temperature fluctuations. Another recent application for this type of coating is infrared emissive imaging employing a fiber optic infrared scene projector. While single layer coatings can provide high emissivity in a broad wavelength band, multilayer coatings can be used to obtain higher emissivities over a narrow wavelength band. This band can be tuned to a specific range of temperatures and wavelengths. Coatings developed for thermal control have a reflective base layer, either ZrN or a refractory metal boride or silicide. These materials have increased durability compared to metal layers. The multilayer coating deposited over the based layer consists of an Al2O3/SiO2 stack with high emittance at 300 K (9.8 mu m), and solar reflectance near 0.6. Multilayer tuned infrared absorber/emitter coatings are applied to fiber optic infrared scene projectors. The coatings consists of a three layer Si3N4/Cr/Si3N4 absorber tuned at the 1.06 mu m laser wavelength, and a six layer Cr/dielectric/Cr/dielectric/Cr/dielectric coating which emits strongly in either the 3 - 5 mu m or the 8 - 12 mu m infrared wavelength bands. Absorption bands of the coatings are independently tunable. All coatings are deposited by reactive DC and RF magnetron sputtering onto 2.5-in fiber optic faceplates. Either Si3N4, Si, or ZnS thin film dielectric materials were used in the emitter coatings. With an input laser power of 15 W, the coatings emit at a black body temperature 529 K, which compared well with predicted performance. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Martin, PM (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. NR 12 TC 1 Z9 1 U1 1 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-461-0 J9 MATER RES SOC SYMP P PY 1999 VL 555 BP 3 EP 12 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science GA BN11Q UT WOS:000080757900001 ER PT S AU Besmann, TM Haynes, JA Cooley, KM Vaubert, VM Lee, WY AF Besmann, TM Haynes, JA Cooley, KM Vaubert, VM Lee, WY BE Johnson, RN Lee, WY Pickering, MA Sheldon, BW TI Corrosion resistant coatings for high temperature applications SO PROPERTIES AND PROCESSING OF VAPOR-DEPOSITED COATINGS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Properties and Processing of Vapor-Deposited Coatings, at the 1998 MRS Fall Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID CERAMICS; EXPANSION AB Efforts to increase efficiency of energy conversion devices have required their operation at ever higher temperatures. This will force the substitution of higher-temperature structural ceramics for lower temperature materials, largely metals. Yet, many of these ceramics will require protection from high temperature corrosion caused by combustion gases, atmospheric contaminants, or the operating medium. This paper discusses examples of the initial development of such coatings and materials for potential application in combustion, aluminum smelting, and other harsh environments. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Besmann, TM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 17 TC 2 Z9 2 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-461-0 J9 MATER RES SOC SYMP P PY 1999 VL 555 BP 109 EP 118 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science GA BN11Q UT WOS:000080757900016 ER PT S AU Allendorf, MD Melius, CF McDaniel, AH AF Allendorf, MD Melius, CF McDaniel, AH BE Johnson, RN Lee, WY Pickering, MA Sheldon, BW TI Thermochemistry and kinetics of gas-phase reactions relevant to the CVD of coatings: New data for process models SO PROPERTIES AND PROCESSING OF VAPOR-DEPOSITED COATINGS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Properties and Processing of Vapor-Deposited Coatings, at the 1998 MRS Fall Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID CHEMICAL-VAPOR-DEPOSITION; CL-H SYSTEM; THEORETICAL CALCULATION; GAUSSIAN-2 THEORY; MOLECULES; CHEMISTRY; FLOW; DECOMPOSITION; ENTHALPIES; PYROLYSIS AB Understanding the role of gas-phase reactions is an important step in the development of useful CVD process models. In this article, we review the general types of gas-phase reactions that can occur and discuss quantum-chemistry techniques for predicting their thermochemistry and kinetics. We also describe the use of high-temperature flow reactors to measure gas-phase reaction kinetics. Coupling these theoretical and experimental methods is a powerful approach to the characterization of CVD precursor chemistry. We illustrate this in a discussion of the reaction between BCl(3) and NH(3), which is important in the deposition of hexagonal boron nitride coatings. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Allendorf, MD (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM mdallen@sandia.gov NR 49 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-461-0 J9 MATER RES SOC SYMP P PY 1999 VL 555 BP 121 EP 134 PG 14 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science GA BN11Q UT WOS:000080757900017 ER PT S AU Jankowski, A Felter, T Patterson, R Hayes, J Anders, S Stamler, T Poker, D AF Jankowski, A Felter, T Patterson, R Hayes, J Anders, S Stamler, T Poker, D BE Johnson, RN Lee, WY Pickering, MA Sheldon, BW TI Nitrogen implantation effects on the chemical bonding and hardness of boron and boron nitride coatings SO PROPERTIES AND PROCESSING OF VAPOR-DEPOSITED COATINGS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Properties and Processing of Vapor-Deposited Coatings, at the 1998 MRS Fall Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID ABSORPTION FINE-STRUCTURE; PULSED-LASER DEPOSITION; THIN-FILMS; SPUTTER-DEPOSITION; ELASTIC-MODULUS; C-BN; GROWTH; INDENTATION; LOAD AB Boron nitride (BN) coatings are deposited by the reactive sputtering of fully dense, boron (B) targets utilizing an argon-nitrogen (Ar-N-2) reactive gas mixture. Near-edge x-ray absorption fine structure analysis reveals features of chemical banding in the B Is photoabsorption spectrum. Hardness is measured at the film surface using nanoindentation. The BN coatings prepared at low, sputter gas pressure with substrate heating are found to have bonding characteristic of a defected hexagonal phase. The coatings are subjected to post-deposition nitrogen (N+ and N-2(+)) implantation at different energies and current densities. The changes in film hardness attributed to the implantation can be correlated to changes observed in the B Is NEXAFS spectra. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Jankowski, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 29 TC 2 Z9 2 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-461-0 J9 MATER RES SOC SYMP P PY 1999 VL 555 BP 371 EP 376 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science GA BN11Q UT WOS:000080757900053 ER PT B AU Soong, Y Link, TA Schoffstall, MR Champagne, KJ Sands, WD Schehl, RR AF Soong, Y Link, TA Schoffstall, MR Champagne, KJ Sands, WD Schehl, RR BE Li, BQ Liu, ZY TI Coal beneficiation via triboelectrostatic separation SO PROSPECTS FOR COAL SCIENCE IN THE 21ST CENTURY LA English DT Proceedings Paper CT 10th International Conference on Coal Science CY SEP 12-17, 1999 CL INST COAL CHEM, ST KEY LAB COAL CONVERS, TAIYUAN, PEOPLES R CHINA SP Int Energy Agcy, Inst Coal Chem, Taiyuan Univ Technol HO INST COAL CHEM, ST KEY LAB COAL CONVERS DE coal beneficiation; triboelectrostatic AB The beneficiation of three types of Slovakian coal was studied using triboelectrostatic separation. Three different types of separators-cylindrical, parallel, and louvered plate separators-were used for this: study. It is found that the quality of separation is dependent upon the type of coal and the configuration of the separator utilized. C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Soong, Y (reprint author), US DOE, Fed Energy Technol Ctr, POB 10940, Pittsburgh, PA 15236 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SHANXI SCIENCE & TECHNOLOGY PRESS PI SHANXI PA 11 BINGZHOU BEILU TALYUAN, SHANXI 03001, PEOPLES R CHINA BN 7-5377-1640-4 PY 1999 BP 1143 EP 1146 PG 4 WC Energy & Fuels SC Energy & Fuels GA BQ24C UT WOS:000087704500282 ER PT B AU Soong, Y Link, TA Schoffstall, MR Champagne, KJ Sands, WD Schehl, RR AF Soong, Y Link, TA Schoffstall, MR Champagne, KJ Sands, WD Schehl, RR BE Li, BQ Liu, ZY TI Coal beneficiation via triboelectrostatic separation SO PROSPECTS FOR COAL SCIENCE IN THE 21ST CENTURY, VOLS I AND II LA English DT Proceedings Paper CT 10th International Conference on Coal Science CY SEP 12-17, 1999 CL INST COAL CHEM, ST KEY LAB COAL CONVERS, TAIYUAN, PEOPLES R CHINA SP Int Energy Agcy, Inst Coal Chem, Taiyuan Univ Technol HO INST COAL CHEM, ST KEY LAB COAL CONVERS DE coal beneficiation; triboelectrostatic AB The beneficiation of three types of Slovakian coal was studied using triboelectrostatic separation. Three different types of separators--cylindrical, parallel, and louvered plate separators--were used for this' study. It is found that the quality of separation is dependent upon the type of coal and the configuration of the separator utilized. C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Soong, Y (reprint author), US DOE, Fed Energy Technol Ctr, POB 10940, Pittsburgh, PA 15236 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SHANXI SCIENCE & TECHNOLOGY PRESS PI SHANXI PA 11 BINGZHOU BEILU TALYUAN, SHANXI 03001, PEOPLES R CHINA BN 7-5377-1650-4 PY 1999 BP 1143 EP 1146 PG 4 WC Energy & Fuels; Engineering, Chemical; Engineering, Petroleum; Mining & Mineral Processing SC Energy & Fuels; Engineering; Mining & Mineral Processing GA BP29H UT WOS:000084595500280 ER PT J AU Huang, K Flanagan, JM Prestegard, JH AF Huang, K Flanagan, JM Prestegard, JH TI The influence of C-terminal extension on the structure of the "J-domain" in E-coli DnaJ SO PROTEIN SCIENCE LA English DT Article DE ATPase stimulatory activity; DnaJ; heat shock protein; molecular chaperone; NMR structure ID PROTEIN SECONDARY STRUCTURE; NUCLEAR-MAGNETIC-RESONANCE; CHEMICAL-SHIFT INDEX; MOLECULAR CHAPERONE; ATPASE ACTIVITY; NMR STRUCTURE; CORRELATION SPECTROSCOPY; C-13-LABELED PROTEINS; IMPROVED SENSITIVITY; NUCLEOTIDE-SEQUENCE AB Two different recombinant constructs of the N-terminal domain in Escherichia coli DnaJ were uniformly labeled with nitrogen-15 and carbon-13. One, DnaJ(1-78), contains the complete "J-domain," and the other, DnaJ(1-104), contains both the "J-domain" and a conserved "G/F' extension st the C-terminus. The three-dimensional structures of these proteins have been determined by heteronuclear NMR experiments. In both proteins the "J-domain" adopts a compact structure consisting of a helix-turn-herix-loop-helix-turn-helix motif. In contrast, the "G/F" region in DnaJ(1-104) does not fold into a well-defined structure. Nevertheless, the "G/F' region has been found to have an effect on the packing of the helices in the "J-domain" in DnaJ(1-104). Particularly, the interhelical angles between Helix IV and other helices are significantly different in the two structures. In addition, there are some local conformational changes in the loop region connecting the two central helices. These structural differences in the "J-domain" in the presence of the "G/F' region may be related to the observation that DnaJ(1-78) is incapable of stimulating the ATPase activity of the molecular chaperone protein DnaK despite evidence that sites mediating the binding of DnaJ to DnaK are located in the 1-78 segment. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Yale Univ, Dept Chem, New Haven, CT 06520 USA. Univ Georgia, Complex Carbohydrate Res Ctr, Athens, GA 30602 USA. RP Flanagan, JM (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. FU NIGMS NIH HHS [GM 53181] NR 54 TC 33 Z9 36 U1 2 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD JAN PY 1999 VL 8 IS 1 BP 203 EP 214 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 155QB UT WOS:000077956900021 PM 10210198 ER PT J AU Zemla, A Venclovas, C Moult, J Fidelis, K AF Zemla, A Venclovas, C Moult, J Fidelis, K TI Processing and analysis of CASP3 protein structure predictions SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article; Proceedings Paper CT 3rd Meeting on the Critical Assessment of Techniques for Protein Structure Prediction (CASP3) CY DEC, 1998 CL PACIFIC GROVE, CA DE prediction evaluation; prediction assessment; comparative modeling; fold recognition; ab initio prediction ID ALIGNMENT AB Livermore Prediction Center provides basic infrastructure for the GASP (Critical Assessment of Structure Prediction) experiments, including prediction processing and verification servers, a system of prediction evaluation tools, and interactive numerical and graphical displays. Here we outline the essentials of our approach, with discussion of the superposition procedures, definitions of basic measures, and descriptions of new methods developed to analyze predictions, Our primary focus is on the evaluation of three-dimensional models and secondary structure predictions. To put the results of the three prediction experiments held to date on the same footing, the latest CASP3 evaluation criteria were retrospectively applied to both CASP1 and CASP2 predictions. Finally, we give an overview of our website (http://PredictionCenter.llnl.gov), which makes the target structures, predictions, and the evaluation system accessible to the community. Published 1999 Wiley-Liss, Inc. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. RP Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. EM fidelis@llnl.gov NR 13 TC 119 Z9 121 U1 1 U2 6 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0887-3585 EI 1097-0134 J9 PROTEINS JI Proteins PY 1999 SU 3 BP 22 EP 29 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 240AU UT WOS:000082804100005 ER PT J AU Venclovas, C Zemla, A Fidelis, K Moult, J AF Venclovas, C Zemla, A Fidelis, K Moult, J TI Some measures of comparative performance in the three CASPs SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article; Proceedings Paper CT 3rd Meeting on the Critical Assessment of Techniques for Protein Structure Prediction (CASP3) CY DEC, 1998 CL PACIFIC GROVE, CA DE protein structure prediction; community wide experiment; CASP AB Performance in the three Critical Assessment of protein Structure Prediction (CASP) experiments has been compared in the areas of alignment accuracy for models based on homology and three-dimensional accuracy for models produced by using ab initio prediction methods. The homologous models span the comparative modeling and fold-recognition regimes. Each CASP target is assigned a relative difficulty based on the extent of sequence identity and the degree of structural overlap with the best available template. There is a clear improvement in alignment accuracy between CASP1 and CASPs 2 and 3 over much of the difficulty scale but no apparent improvement between CASP2 and CASP3. Encouragingly, the best ab initio models of small targets are clearly more accurate in CASP3 than in CASPs 1 and 2. Published 1999 Wiley-Liss, Inc.dagger. C1 Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. RP Moult, J (reprint author), Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. EM jmoult@carb.nist.gov NR 8 TC 32 Z9 34 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0887-3585 J9 PROTEINS JI Proteins PY 1999 SU 3 BP 231 EP 237 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 240AU UT WOS:000082804100030 ER PT J AU Moult, J Hubbard, T Fidelis, K Pedersen, JT AF Moult, J Hubbard, T Fidelis, K Pedersen, JT TI Critical assessment of methods of protein structure prediction (CASP): Round III SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Editorial Material DE protein structure prediction; community wide experiment; CASP ID RECOGNITION C1 Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Acadia Pharmaceut, Glostrup, Denmark. RP Moult, J (reprint author), Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. RI Hubbard, Tim/C-2567-2008 OI Hubbard, Tim/0000-0002-1767-9318 NR 14 TC 41 Z9 44 U1 1 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-3585 J9 PROTEINS JI Proteins PY 1999 SU 3 BP 2 EP 6 PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 240AU UT WOS:000082804100002 ER PT J AU Venclovas, C Ginalski, K Fidelis, K AF Venclovas, C Ginalski, K Fidelis, K TI Addressing the issue of sequence-to-structure alignments in comparative modeling of CASP3 target proteins SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Article; Proceedings Paper CT 3rd Meeting on the Critical Assessment of Techniques for Protein Structure Prediction (CASP3) CY DEC, 1998 CL PACIFIC GROVE, CALIFORNIA DE protein structure prediction; three-dimensional model; model evaluation; low sequence homology; alignment errors ID SECONDARY STRUCTURE; RECOGNITION; PREDICTION; MATRICES AB During a blind protein structure prediction experiment (the third round of the Critical Assessment of Techniques for Protein Structure Prediction; URL http://PredictionCenter.llnl.gov/casp3/), four target proteins, T0047, T0048, T0055, and T0070, were modeled by comparison. These proteins display 62%, 29%, 24%, and 19% sequence identity, respectively, to the structurally homologous proteins most similar in sequence. The issue of sequence-to-structure alignment in cases of low sequence homology was the main emphasis. Selection of alignments was made by constructing and evaluating three-dimensional models based on series of samples produced mainly by automatic multiple sequence alignments. Sequence-to-structure alignments were correct in all but two regions, in which significant changes in target structures compared with related proteins were the source of errors. Template choice is an important determinant of model quality, and a correct selection was made of a lower homology template for modeling of T0070; however in the case of T0055, a template with 8% greater sequence homology proved deceptive. Loops and some ungapped template regions were assigned conformations taken from other proteins. Using fragments from homologous structures led to improvement over template backbone more often than cases in which nonhomologous structures were the source. The results also indicate that side-chain prediction accuracy depends not only on sequence similarity but also on accuracy of the backbone. Published 1999 Wiley-Liss, Inc.(dagger) C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. Inst Biotechnol, LT-2028 Vilnius, Lithuania. Univ Warsaw, Inst Phys Expt, Dept Biophys, PL-02089 Warsaw, Poland. RP Venclovas, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. NR 19 TC 5 Z9 5 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-3585 J9 PROTEINS JI Proteins PY 1999 SU 3 BP 73 EP 80 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 240AU UT WOS:000082804100011 ER PT J AU Lederman, L AF Lederman, L TI Science, technology and citizenship SO PUBLIC UNDERSTANDING OF SCIENCE LA English DT Book Review C1 Fermilab, Batavia, IL USA. RP Lederman, L (reprint author), Fermilab, Batavia, IL USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0963-6625 J9 PUBLIC UNDERST SCI JI Public Underst. Sci. PD JAN PY 1999 VL 8 IS 1 BP 65 EP 66 DI 10.1088/0963-6625/8/1/006 PG 2 WC Communication; History & Philosophy Of Science SC Communication; History & Philosophy of Science GA 186ZX UT WOS:000079762400009 ER PT B AU Hatano, N AF Hatano, N BE Ono, YA Fujikawa, K TI Non-Hermitian quantum mechanics and localization in physical systems SO QUANTUM COHERENCE AND DECOHERENCE SE NORTH-HOLLAND DELTA SERIES LA English DT Proceedings Paper CT 6th International Symposium on Foundations of Quantum Mechanics in the Light of New Technology (ISQM-Tokyo 98) CY AUG 24-27, 1998 CL ADV RES LAB, HITACHI LTD, HATOYAMA, JAPAN SP Phys Soc Japan, Japan Soc Appl Phys, Adv Res Lab, Hitachi Ltd HO ADV RES LAB, HITACHI LTD ID DISORDER; DENSITY AB Recent study on a delocalization phenomenon of a non-Hermitian random system is reviewed. A complex energy spectrum of the system indicates delocalization transition of its eigenfunctions. It is demonstrated that, using this property, one can calculate the localization length of the Hermitian Anderson model by inspecting the complex energy spectrum of its non-Hermitian version. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Hatano, N (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS-B262, Los Alamos, NM 87545 USA. NR 35 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-50091-X J9 N-HOLLAND D PY 1999 BP 319 EP 322 DI 10.1016/B978-044450091-5/50070-1 PG 4 WC Physics, Applied SC Physics GA BP93Y UT WOS:000086691300066 ER PT S AU Cleve, R van Dam, W Nielsen, M Tapp, A AF Cleve, R van Dam, W Nielsen, M Tapp, A BE Williams, CP TI Quantum entanglement and the communication complexity of the inner product function SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CALIFORNIA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol AB We consider the communication complexity of the binary inner product function in a variation of the two-party scenario where the parties have an a priori supply of particles in an entangled quantum state. We prove linear lower bounds for both exact protocols, as well as for protocols that determine the answer with bounded-error probability. Our proofs employ a novel kind of "quantum" reduction from a quantum information theory problem to the problem of computing the inner product. The communication required for the former problem can then be bounded by an application;of Holevo's theorem. We also give a specific example of a probabilistic scenario where entanglement reduces the communication complexity of the inner product function by one bit. C1 Univ Calgary, Dept Comp Sci, Calgary, AB T2N 1N4, Canada. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. CWI, NL-1009 AB Amsterdam, Netherlands. Univ New Mexico, Albuquerque, NM 87131 USA. Univ Montreal, Dept IRO, Montreal, PQ H3C 3J7, Canada. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Montreal, Lab Informat Theor & Quant, Montreal, PQ H3C 3J7, Canada. RP Cleve, R (reprint author), Univ Calgary, Dept Comp Sci, Calgary, AB T2N 1N4, Canada. NR 18 TC 51 Z9 51 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 61 EP 74 PG 14 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300004 ER PT S AU Hughes, RJ Buttler, WT Kwiat, PG Lamoreaux, SK Luther, GG Morgan, GL Nordholt, JE Peterson, CG Simmons, CM AF Hughes, RJ Buttler, WT Kwiat, PG Lamoreaux, SK Luther, GG Morgan, GL Nordholt, JE Peterson, CG Simmons, CM BE Williams, CP TI Practical free-space quantum cryptography SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CALIFORNIA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol ID OPTICAL-FIBER; LONG AB An experimental free-space quantum key distribution (QKD) system has been tested over an outdoor optical path of similar to 1 km under nighttime conditions at Los Alamos National Laboratory. This system employs the Bennett 92 protocol; here we give a brief overview of this protocol, and describe bur experimental implementation of it. An analysis of the system efficiency is presented, as well as a description of our error detection protocol, which employs a two-dimensional parity check scheme. Finally, the susceptibility of this system to eavesdropping by various techniques is determined, and the effectiveness of privacy amplification procedures is discussed. Our conclusions are that free-space QKD is both effective and secure; possible applications include the rekeying of satellites in low earth orbit. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hughes, RJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 24 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 200 EP 213 PG 14 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300017 ER PT S AU Gottesman, D AF Gottesman, D BE Williams, CP TI Fault-tolerant quantum computation with higher-dimensional systems SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CALIFORNIA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol ID ERROR-CORRECTING CODES AB Instead of a quantum computer where the fundamental units are 2-dimensional qubits, we can consider a quantum computer made up of d-dimensional systems. There is a straightforward generalization of the class of stabilizer codes to d-dimensional systems, and I will discuss the theory of fault-tolerant computation using such codes. I prove that universal fault-tolerant computation is possible with any higher-dimensional stabilizer code for prime d. C1 Univ Calif Los Alamos Natl Lab, T6 Grp, Los Alamos, NM 87544 USA. RP Gottesman, D (reprint author), Univ Calif Los Alamos Natl Lab, T6 Grp, POB 1663, Los Alamos, NM 87544 USA. NR 12 TC 43 Z9 45 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 302 EP 313 PG 12 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300027 ER PT S AU Laflamme, R Knill, E Zurek, WH Catasti, P Mariappan, SVS AF Laflamme, R Knill, E Zurek, WH Catasti, P Mariappan, SVS BE Williams, CP TI NMR GHZ SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol ID QUANTUM LOGIC GATE; COMPUTATION; UNIVERSAL AB We describe the creation of a Greenberger-Horne-Zeilinger (GHZ) state of the form (\000] + \111])/root 2 (three maximally entangled quantum bits) using Nuclear Magnetic Resonance (NMR). We have successfully carried out the experiment using the proton and carbon spins of trichloroethylene, and confirmed the result using state tomography. We have thus extended the space of entangled quantum states explored systematically to three quantum bits, an essential step for quantum computation. C1 Los Alamos Natl Lab, Los Alamos, NM 87455 USA. RP Laflamme, R (reprint author), Los Alamos Natl Lab, MS B-288, Los Alamos, NM 87455 USA. NR 19 TC 0 Z9 0 U1 0 U2 3 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 357 EP 363 PG 7 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300032 ER PT S AU James, DFV Gulley, MS Holzscheiter, MH Hughes, RJ Kwiat, PG Lamoreaux, SK Peterson, CG Sandberg, VD Schauer, MM Simmons, CM Tupa, D Wang, PZ White, AG AF James, DFV Gulley, MS Holzscheiter, MH Hughes, RJ Kwiat, PG Lamoreaux, SK Peterson, CG Sandberg, VD Schauer, MM Simmons, CM Tupa, D Wang, PZ White, AG BE Williams, CP TI Trapped ion quantum computer research at Los Alamos SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CALIFORNIA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol ID DECOHERENCE BOUNDS; LOGIC; COMPUTATION AB We briefly review the development and theory of an experiment to investigate quantum computation with trapped calcium ions. The ion trap, laser and ion requirements are determined, and the parameters required for simple quantum logic operations are described. (LAUR 98-314). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP James, DFV (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI James, Daniel/B-9805-2009; White, Andrew/A-1088-2009 OI James, Daniel/0000-0003-3981-4602; White, Andrew/0000-0001-9639-5200 NR 37 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 426 EP 437 PG 12 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300039 ER PT S AU Kalos, MH Pederiva, F AF Kalos, MH Pederiva, F BE Nightingale, MP Umrigar, CJ TI Fermion Monte Carlo SO QUANTUM MONTE CARLO METHODS IN PHYSICS AND CHEMISTRY SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT NATO Advanced Study Institute on Quantum Monte Carlo Methods in Physics and Chemistry CY JUL 12-24, 1998 CL CORNELL UNIV, ITHACA, NY SP NATO Adv Study Inst, Natl Sci Fdn, Ctr Europeen Calcul Atom Molec, Cornell Univ HO CORNELL UNIV ID CORRELATED PAIRS; RANDOM-WALK; HE-3 AB We review the fundamental challenge of fermion Monte Carlo for continuous systems, the "sign problem", and some of the proposals that have been made for its solution, including some approximate schemes and others whose computing requirements grow exponentially. The issue is to find the lowest eigenmode of the Schrodinger equation in many dimensions that has a special inversion of sign- antisymmetry in the exchange of pairs of coordinates. Thus the function sought is not everywhere positive. We also describe a class of methods that depend upon the use of correlated dynamics for ensembles of walkers that carry opposite signs. We discuss the algorithmic symmetry between such walkers that must be broken to create a method that is both exact and as effective as for treating the fundamental symmetric solution. We explain the concept of marginally correct dynamics. Stable overlaps with an antisymmetric trial function given by such dynamics correspond to the lowest antisymmetric mode. As an elementary example, we show how walkers correlated in a purely geometric way can find an antisymmetric wave function for a particle in a parallelogram. Many-body harmonic oscillator problems are particularly tractable: Their stochastic dynamics permits the use of regular geometric structures for the ensembles, structures that are stable when appropriate correlations are introduced, and thereby avoid the decay of signal-to-noise that is a normal characteristic of the sign problem. Finally, me outline a new generalization of the method for arbitrary potentials and describe its success in treating few-electron systems, free fermions, and He-3. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kalos, MH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-5551-2 J9 NATO ADV SCI I C-MAT PY 1999 VL 525 BP 263 EP 286 PG 24 WC Chemistry, Multidisciplinary; Mechanics; Physics, Multidisciplinary; Physics, Mathematical SC Chemistry; Mechanics; Physics GA BM60H UT WOS:000079219100010 ER PT S AU Carlson, J AF Carlson, J BE Nightingale, MP Umrigar, CJ TI Quantum Monte Carlo in nuclear physics SO QUANTUM MONTE CARLO METHODS IN PHYSICS AND CHEMISTRY SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT NATO Advanced Study Institute on Quantum Monte Carlo Methods in Physics and Chemistry CY JUL 12-24, 1998 CL CORNELL UNIV, ITHACA, NY SP NATO Adv Study Inst, Natl Sci Fdn, Ctr Europeen Calcul Atom Molec, Cornell Univ HO CORNELL UNIV ID FEW-BODY NUCLEI; LIGHT-NUCLEI; COULOMB SUM; FREEDOM; HE-4 C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Carlson, J (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-5551-2 J9 NATO ADV SCI I C-MAT PY 1999 VL 525 BP 287 EP 312 PG 26 WC Chemistry, Multidisciplinary; Mechanics; Physics, Multidisciplinary; Physics, Mathematical SC Chemistry; Mechanics; Physics GA BM60H UT WOS:000079219100011 ER PT J AU Bretherton, CS Macvean, MK Bechtold, P Chlond, A Cotton, WR Cuxart, J Cuijpers, H Khairoutdinov, M Kosovic, B Lewellen, D Moeng, CH Siebesma, P Stevens, B Stevens, DE Sykes, I Wyant, MC AF Bretherton, CS Macvean, MK Bechtold, P Chlond, A Cotton, WR Cuxart, J Cuijpers, H Khairoutdinov, M Kosovic, B Lewellen, D Moeng, CH Siebesma, P Stevens, B Stevens, DE Sykes, I Wyant, MC TI An intercomparison of radiatively driven entrainment and turbulence in a smoke cloud, as simulated by different numerical models SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE entrainment; large-eddy simulation; stratocumulus ID LARGE-EDDY-SIMULATION; PLANETARY BOUNDARY-LAYER; VERTICAL-VELOCITY SKEWNESS; ADVECTION SCHEME; STRATOCUMULUS; CUMULUS; TOP; INSTABILITY; TRANSITION; TRANSPORT AB As part of a programme of intercomparison of eddy-resolving and one-dimensional (1-D) boundary-layer models, a convective boundary-layer filled with radiatively active 'smoke' was simulated. The programme is sponsored by the Global Energy and Water Experiment Cloud Systems Study. Cloud-top-cooling rates were chosen to be comparable with those observed in marine stratocumulus, while avoiding evaporative feedbacks on entrainment and turbulence that are also important in liquid-water clouds. The radiative-cooling rate had a specified dependence on the smoke profile, so that differences between simulations could only be a result of different numerical representations of fluid motion and subgrid-scale turbulence. At a workshop in De Bilt, The Netherlands in August 1995, results from numerous groups around the world were compared with each other and with a previously investigated laboratory analogue to the smoke cloud. The intercomparison results show that models must be run with higher vertical resolution in the inversion than is customary at present, in order to accurately simulate the entrainment rate into cloud-topped boundary-layers under strong inversions. in three-dimensional (3-D) models using a vertical grid spacing of 5-12.5 m, sufficient to resolve the horizontal variability of inversion height, entrainment rates were 10-50% larger than the range consistent with the laboratory experiments. With a larger vertical grid spacing of 25 m, 1-D, 2-D and 3-D models all overestimated the entrainment rate by more than 50%. 3-D models with monotone advection-schemes overestimated entrainment slightly more than those with non-monotone schemes, at least when 25 m vertical grid-spacing was used. However, results from non-monotone schemes had several undesirable features associated with the generation of undershoots and overshoots, most notably spurious turbulent mixing above the smoke layer. The 1-D models tended to underestimate turbulent kinetic energy (TKE) but performed reasonably well given their simplicity. 2-D models produced too much entrainment and considerably overestimated TKE, compared with 3-D models with the same numerical formulation. Based on a simple scaling-argument, we propose that the minimum vertical grid-spacing required to obtain an accurate entrainment-rate is of the order of the horizontal fluctuations in inversion height, which is proportional to the layer-averaged TKE and inversely proportional to the inversion strength. C1 Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Meteorol Off, Bracknell RB12 2SZ, Berks, England. Observ Midi Pyrenees, F-31400 Toulouse, France. Max Planck Inst Meteorol, Hamburg, Germany. Colorado State Univ, Ft Collins, CO 80523 USA. Inst Marine & Atmospher Res, Utrecht, Netherlands. Univ Oklahoma, Oklahoma City, OK USA. Univ Colorado, Boulder, CO 80309 USA. W Virginia Univ, Morgantown, WV 26506 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bretherton, CS (reprint author), Univ Washington, Dept Atmospher Sci, Box 351640, Seattle, WA 98195 USA. RI Lewellen, David/B-1453-2008; Stevens, Bjorn/A-1757-2013 OI Stevens, Bjorn/0000-0003-3795-0475 NR 49 TC 96 Z9 97 U1 1 U2 4 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING, BERKS, ENGLAND RG1 7LJ SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD JAN PY 1999 VL 125 IS 554 BP 391 EP 423 DI 10.1256/smsqj.55401 PN B PG 33 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 179VK UT WOS:000079350100001 ER PT J AU Slingo, JM Rowell, DP Sperber, KR Nortley, E AF Slingo, JM Rowell, DP Sperber, KR Nortley, E TI On the predictability of the interannual behaviour of the Madden-Julian Oscillation and its relationship with El Nino SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE El Nino; intraseasonal variability; predictability ID OUTGOING LONGWAVE RADIATION; INTRASEASONAL CONVECTION ANOMALIES; ATMOSPHERIC ANGULAR-MOMENTUM; GENERAL-CIRCULATION MODEL; SUMMER MONSOON; VARIABILITY; PACIFIC; TEMPERATURE; SIMULATIONS; REANALYSIS AB The Madden-Julian Oscillation (MJO) is the dominant mode of tropical variability at intraseasonal timescales. It displays substantial interannual variability in intensity which may have important implications for the predictability of the coupled system. The reasons for this interannual variability are not understood. The aim of this paper is to investigate whether the interannual behaviour of the MJO is related to tropical sea surface temperature (SST) anomalies, particularly El Nino, and hence whether it is predictable. The interannual behaviour of the MJO has been diagnosed initially in the 40-year National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis. The results suggest that prior to the mid-1970s the activity of the MJO was consistently lower than during the latter part of the record. This may be related either to inadequacies in the data coverage, particularly over the tropical Indian Ocean prior to the introduction of satellite observations, or to the real effects of a decadal time-scale warming in the tropical SSTs. The teleconnection patterns between interannual variations in MJO activity and SST show only a weak, barely significant, influence of El Nino in which the MJO is more active during the cold phase. As well as the NCEP/NCAR Reanalysis, a 4-member ensemble of 45-year integrations with the Hadley Centre climate model (HadAM2a), forced by observed SSTs for 1949-93, has been used to investigate the relationship between MJO activity and SST. HadAM2a is known to give a reasonable simulation of the MJO, and the extended record provided by this ensemble of integrations allows a more robust investigation of the predictability of MJO activity than was possible with the 40-year NCEP/NCAR Reanalysis. The results have shown that, for the uncoupled system, with the atmosphere being driven by imposed SSTs, there is no reproducibility of the activity of the MJO from year-to-year. The interannual behaviour of the MJO is not controlled by the phase of El Nino and would appear to be mainly chaotic in character. However, the model results have confirmed the low-frequency, decadal time-scale variability of MJO activity seen in the NCEP/NCAR Reanalysis. The activity of the MJO is consistently lower in all realizations prior to the mid-1970s, suggesting that the MJO may become more active as tropical SSTs increase. This result may have implications for the effects of global warming on the coupled tropical atmosphere-ocean system. Since the observed and simulated MJOs display clear seasonality in their occurrence, the relationship with interannual changes in the mean seasonal cycle of the tropical circulation has also been investigated. In contrast to the MJO, the interannual variability in the mean seasonal cycle is reproducible and influenced by the phase of El Nino. The implications of these results for the predictability of the tropical atmosphere-ocean system are discussed, particularly with reference to the strong El Nino event of 1997 which developed in association with a period of intense MJO activity. C1 Univ Reading, Dept Meteorol, Ctr Global Atmospher Modelling, Reading RG6 6BB, Berks, England. Meteorol Off, Bracknell RB12 2SZ, Berks, England. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Slingo, JM (reprint author), Univ Reading, Dept Meteorol, Ctr Global Atmospher Modelling, Earley Gate, Reading RG6 6BB, Berks, England. RI Sperber, Kenneth/H-2333-2012 NR 51 TC 188 Z9 211 U1 0 U2 18 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING, BERKS, ENGLAND RG1 7LJ SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD JAN PY 1999 VL 125 IS 554 BP 583 EP 609 DI 10.1256/smsqj.55410 PN B PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 179VK UT WOS:000079350100010 ER PT B AU Wills, BJ Brotherton, MS Laor, A Wills, D Wilkes, BJ Ferland, GJ Shang, ZH AF Wills, BJ Brotherton, MS Laor, A Wills, D Wilkes, BJ Ferland, GJ Shang, ZH BE Ferland, G Baldwin, J TI The PG X-ray QSO sample: Links between the UV-X-ray continuum and emission lines SO QUASARS AND COSMOLOGY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Meeting on Quasars and Cosmology CY MAY 18-22, 1998 CL LA SERENA, CHILE SP Astron Soc Pacific ID ACTIVE GALACTIC NUCLEI; OPTICALLY SELECTED QUASARS; FE-II EMISSION; ULTRAVIOLET; SPECTRA; CLOUDS; GALAXY AB The UV to soft X-rays of luminous AGNs dominate their bolometric luminosity, driven by an accretion-powered dynamo at the center. These photons ionize the surrounding gas, thereby providing clues to fueling and exhaust. Two sets of important relationships - neither of them understood - link the continuum and gas properties. (i) Boroson & Green's 'eigenvector 1' relationships: Steeper soft X-ray spectra are clearly related to narrower H beta emission and stronger optical Fe II emission from the BLR, and weaker [O III] lambda 5007 from the NLR. We show that these relationships extend to UV spectra: narrower C III]lambda 1909, stronger low ionization lines, larger Si III]lambda 1892/C III]lambda 1909 (a density indicator), weaker CIV lambda 1549 but stronger higher-ionization NV lambda 1240. We speculate that high accretion rates are linked to high columns of dense (10(10) - 10(11) cm(-3)), nitrogen-enhanced, low-ionization gas from nuclear starbursts. Linewidth, inverse FeII-[O III] and inverse FeII-CIV relationships hint at the geometrical arrangement of this gas. (ii) The Baldwin effect (inverse equivalent width - luminosity relationships): Our correlation analyses suggest that these are independent of the above eigenvector 1 relationships. The eigenvector 1 relationships can therefore be used in future work, to reduce scatter in the Baldwin relationships, perhaps fulfilling the dream of using the Baldwin effect for cosmological studies. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Wills, BJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. OI Ferland, Gary/0000-0003-4503-6333 NR 24 TC 9 Z9 9 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-83-X J9 ASTR SOC P PY 1999 VL 162 BP 373 EP 384 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27U UT WOS:000081412200026 ER PT B AU Brotherton, MS Francis, PJ AF Brotherton, MS Francis, PJ BE Ferland, G Baldwin, J TI The intermediate line region and the Baldwin effect SO QUASARS AND COSMOLOGY SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT Meeting on Quasars and Cosmology CY MAY 18-22, 1998 CL LA SERENA, CHILE SP Astron Soc Pacific ID ACTIVE GALACTIC NUCLEI; OPTICALLY SELECTED QUASARS; X-RAY PROPERTIES; EMISSION-LINE; FE-II; RADIO PROPERTIES; COMPLETE SAMPLE; QSOS; IONIZATION; STATISTICS AB Statistical investigations of samples of quasars have established that clusters of properties are correlated. The strongest trends among the ultraviolet emission-line properties are characterized by the object-to-object variation of emission from low-velocity gas, the so-called "intermediate-line region" or ILR. The strongest trends among the optical emission-line properties are characterized by the object-to-object variation of the line intensity ratio of [O III] lambda 5007 to optical Fe II. Additionally, the strength of ILR emission correlates with [O III]/Fe II, as well as with radio and X-ray properties. The fundamental physical parameter driving these related correlations is not yet identified. Because the variation in the ILR dominates the variation in the equivalent widths of lines showing the Baldwin effect, it is important to understand whether the physical parameter underlying this variation also drives the Baldwin effect or is a primary source of scatter in the Baldwin effect. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. NR 46 TC 17 Z9 17 U1 0 U2 1 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-83-X J9 ASTR SOC P PY 1999 VL 162 BP 395 EP + PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN27U UT WOS:000081412200028 ER PT S AU Yan, YF Pennycook, SJ Tsai, AP AF Yan, YF Pennycook, SJ Tsai, AP BE Dubois, JM Thiel, PA Tsai, AP Urban, K TI Chemical disorder and columnar vacancies in ideal decagonal Al-Ni-Co quasicrystals SO QUASICRYSTALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Quasicrystals, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID QUASI-CRYSTALS; ORDERED STRUCTURES; AL65CU20CO15 AB Atomic-resolution Z-contrast images provide conclusive evidence for chemical disorder in an ideal Al-Ni-Co quasicrystal. The so-called basic Ni-rich, high-temperature, quasiperiodic structure exhibits chemical disorder at the center of the 2 nm diameter clusters that involves both the Al and Ni(Co) atoms. The atomic structure of the 2 nm clusters is derived directly from the images and differs from previous models. The presence of closely-spaced, half-occupied atomic columns (or columnar vacancies) in specific rings within the clusters is directly observed. We propose that these columnar vacancies mediate the phason flips necessary for transformation to random tiling. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Yan, YF (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-459-9 J9 MATER RES SOC SYMP P PY 1999 VL 553 BP 189 EP 194 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN11P UT WOS:000080756400025 ER PT S AU Jenks, CJ AF Jenks, CJ BE Dubois, JM Thiel, PA Tsai, AP Urban, K TI Surface characteristics of quasicrystalline materials: An overview of work conducted at Ames laboratory SO QUASICRYSTALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Quasicrystals, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID AL-CU-FE; ENERGY-ELECTRON DIFFRACTION; AL70PD21MN9 QUASI-CRYSTAL; PD-MN; METHANOL DECOMPOSITION; ICOSAHEDRAL PHASE; CO; ADSORPTION; ALUMINUM; OXIDATION AB Over the last few years, work in our laboratories in Ames has focussed on elucidating the surface characteristics of Al-based quasicrystalline materials, namely icosahedral (i-) Al-Cu-Fe and i-Al-Pd-Mn. Our work involves the study of the clean surfaces of these materials under ultrahigh vacuum conditions. We find that surfaces cleaned by Ar+ sputtering are depleted in Al relative to the bulk composition. Single grains, after sputtering, undergo a two-stage regrowth process as they are annealed. After heating to about 600 K, a crystalline overlayer is formed. This is rather abruptly replaced at about 750 K by a surface that appears quasicrystalline within the resolution of the experimental techniques used. Calculations based on low-energy electron diffraction (LEED) measurements of this higher temperature state indicate that the Al-rich layers in the bulk model of these materials are the favored surface terminations. Results of low-energy ion scattering (LEIS) corroborate this finding. Consistent with this, we find that the oxidation behavior and general reactivity of these materials are analogous to pure Al. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Jenks, CJ (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 57 TC 14 Z9 14 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-459-9 J9 MATER RES SOC SYMP P PY 1999 VL 553 BP 219 EP 230 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA BN11P UT WOS:000080756400029 ER PT S AU Heinzig, MW Warren, OL Shen, Z Jenks, CJ Lograsso, TA Thiel, PA AF Heinzig, MW Warren, OL Shen, Z Jenks, CJ Lograsso, TA Thiel, PA BE Dubois, JM Thiel, PA Tsai, AP Urban, K TI LEED investigations of a cubic Al-Pd-Mn (110) alloy SO QUASICRYSTALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Quasicrystals, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID QUASI-CRYSTALS AB An Al-Pd-Mn cubic alloy having a bulk chemical composition somewhat analogous to that of the icosahedral Al-Pd-Mn quasicrystal is studied. Our goal is to compare the surface structure and properties of the cubic alloy with those of the quasicrystalline alloy. In this paper, we report the first observations for the (110) surface of the cubic alloy using (primarily) low energy electron diffraction(LEED). The surface is prepared by sputtering and annealing in ultrahigh vacuum (UHV). In addition to the substrate LEED pattern, at least three superstructures evolve sequentially with annealing temperature. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Heinzig, MW (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-459-9 J9 MATER RES SOC SYMP P PY 1999 VL 553 BP 251 EP 256 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN11P UT WOS:000080756400033 ER PT S AU Pinhero, PJ Sordelet, DJ Anderegg, JW Brunet, P Dubois, JM Thiel, PA AF Pinhero, PJ Sordelet, DJ Anderegg, JW Brunet, P Dubois, JM Thiel, PA BE Dubois, JM Thiel, PA Tsai, AP Urban, K TI Room temperature oxidation of Al-Cu-Fe and Al-Cu-Fe-Cr quasicrystals SO QUASICRYSTALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Quasicrystals, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc AB We have investigated formation of oxides on quasicrystalline and crystalline alloy surfaces of similar composition, in different oxidizing environments. This includes a comparison between a quaternary orthorhombic approximate of Al-Cu-Fe-Cr quasicrystal and the ternary Al-Cu-Fe quasicrystalline and crystalline phases. We noted that each sample showed the following common trends: preferential oxidation of the Al, enrichment in the concentration of Al present at the surface upon oxidation, water concentration is directly related to oxide thickness, and the oxide thickness displays a strong correlation with the bulk concentration of Al in the sample. C1 Iowa State Univ Sci & Technol, Ames Lab, Mat Chem Program, Ames, IA 50011 USA. RP Pinhero, PJ (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Mat Chem Program, Ames, IA 50011 USA. NR 9 TC 16 Z9 16 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-459-9 J9 MATER RES SOC SYMP P PY 1999 VL 553 BP 263 EP 268 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BN11P UT WOS:000080756400035 ER PT S AU Sordelet, DJ Kim, JS Besser, MF AF Sordelet, DJ Kim, JS Besser, MF BE Dubois, JM Thiel, PA Tsai, AP Urban, K TI Dry sliding of polygrained quasicrystalline and crystalline Al-Cu-Fe alloys SO QUASICRYSTALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Quasicrystals, at the 1998 Fall MRS Meeting CY NOV 30-DEC 02, 1998 CL BOSTON, MA SP Mat Res Soc ID QUASI-CRYSTALS; COATINGS AB Dry sliding friction and wear experiments were performed with pin-on-disc techniques using WC and brass pins in contact with quasicrystalline (Al65Cu23Fe12) and crystalline (Al50Cu35Fe15 and Al70Cu20Fe10) discs, which were prepared by powder metallurgy routes. The contact loads (1, 5 and 10 N) used in this study produced similar coefficients of friction 0.3-0.4 for the Al65Cu23Fe12 and Al50Cu35Fe15 phases. These values are higher than previously reported for quasicrystalline and related crystalline phases. Possible reasons for these differences are presented. The contrasting wear behavior between different pins and discs is discussed in terms of contact area, oxidation, material transfer mechanisms and fracture characteristics. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Sordelet, DJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 15 TC 12 Z9 15 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-459-9 J9 MATER RES SOC SYMP P PY 1999 VL 553 BP 459 EP 470 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA BN11P UT WOS:000080756400060 ER PT J AU Vadillo, JM Cardell, K Cremers, DA Laserna, JJ AF Vadillo, JM Cardell, K Cremers, DA Laserna, JJ TI Rapid screening method for heavy metals in contaminated soils using LIBS SO QUIMICA ANALITICA LA English DT Article DE laser-induced breakdown spectrometry; LIBS; laser plasma; soil analysis; aerosol ID INDUCED BREAKDOWN SPECTROSCOPY; ELEMENTAL ANALYSIS; LASER-ABLATION; SPECTROMETRY; DETECTOR; SAMPLES AB Laser-induced breakdown spectrometry (LIBS) has been used to analyze soil aerosols generated inside sealed vials. The reproducibility of the method was shown to be 2-3 times better than using pressed samples. The advantages of the method include a great simplicity as the sample can be directly taken from the location site, the capability for analysis without any manipulation other than sieving, and the absence of contamination risk with highly polluted soils as there is no direct contact during the analysis, and the residues are confined inside the vial. Linear calibration curves between 1-1000 ppm for Cr, Cu, Ni, Sr and Pb were obtained, as well as detection limits in the range between 5 and 20 ppm with correlation coefficients better than 0.99. A strong dependence of the spectra with grain size was observed. C1 Univ Calif Los Alamos Natl Lab, CST 1, Los Alamos, NM 87545 USA. RP Laserna, JJ (reprint author), Univ Malaga, Fac Sci, Dept Analyt Chem, Malaga 29071, Spain. RI Vadillo, Jose/I-5334-2013; Laserna, Javier/C-6637-2013 OI Laserna, Javier/0000-0002-2653-9528 NR 23 TC 5 Z9 5 U1 1 U2 4 PU ELSEVIER INFORMACION PROFESSIONAL, S A PI BARCELONA PA C/ENTENCA, 28 ENTL, 08015 BARCELONA, SPAIN SN 0212-0569 J9 QUIM ANAL JI Quim. Anal. PY 1999 VL 18 IS 2 BP 169 EP 174 PG 6 WC Chemistry, Analytical SC Chemistry GA 226NF UT WOS:000082025500002 ER PT J AU Bridges, F Booth, CH Cao, D Anderson, M AF Bridges, F Booth, CH Cao, D Anderson, M TI The important role of local distortions and their connection with magnetism and transport in the "colossal" magnetoresistance systems, La(1-x)A(x)MnO(3) SO RADIATION EFFECTS AND DEFECTS IN SOLIDS LA English DT Article; Proceedings Paper CT 8th Europhysical Conference on Defects in Insulating Materials (EURODIM98) CY JUL 06-11, 1998 CL UNIV KEELE, KEELE, ENGLAND HO UNIV KEELE DE CMR; XAFS; polarons ID THIN-FILMS; LA1-XCAXMNO3; LA1-XSRXMNO3; MANGANITES; CHARGE; MAGNETOTRANSPORT; RESISTIVITY; DIFFRACTION AB Large magnetoresistance (MR) effects have been observed in the substituted systems La(1-x)A(x)MnO(3) (A = Sr, Ca, Ba, Pb, etc.). Most work have been interpreted in terms of the double-exchange (DE) model which assumes Mn+3 and Mn+4 sites exist. Recently Millis has suggested that local distortions, in the form of polarons, must also be present to explain the magnitude of the MR. We present X-ray absorption fine structure (XAFS) data which confirm that local distortions are indeed present and show that the distortions are correlated with magnetization. However, the near edge data are not consistent with charge localization on some of the Mn sites; all Mn appear to have the same average valence. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bridges, F (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RI Booth, Corwin/A-7877-2008 NR 30 TC 1 Z9 1 U1 1 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1042-0150 J9 RADIAT EFF DEFECT S JI Radiat. Eff. Defects Solids PY 1999 VL 149 IS 1-4 BP 221 EP 231 DI 10.1080/10420159908230159 PG 11 WC Nuclear Science & Technology; Physics, Fluids & Plasmas; Physics, Condensed Matter SC Nuclear Science & Technology; Physics GA 333GT UT WOS:000088123100037 ER PT J AU de la Rubia, TD Caturla, MJ Alonso, EA Soneda, N Johnson, MD AF de la Rubia, TD Caturla, MJ Alonso, EA Soneda, N Johnson, MD TI The primary damage state and its evolution over multiple length and time scales: Recent atomic-scale computer simulation studies SO RADIATION EFFECTS AND DEFECTS IN SOLIDS LA English DT Article; Proceedings Paper CT Kiritani Symposium on Structural Defects in Advanced Materials CY DEC 18-20, 1996 CL INUYAMA, JAPAN DE molecular dynamics; Monte Carlo; radiation damage; semiconductor doping ID MOLECULAR-DYNAMICS SIMULATIONS; ION-IMPLANTED SILICON; DISPLACEMENT CASCADES; DEFECT PRODUCTION; POINT-DEFECTS; ENHANCED DIFFUSION; BCC METALS; IRRADIATION; COPPER; TRANSFORMATIONS AB During his long and illustrious career, Professor Kiritani made many of the most significant and revealing observations regarding the nature of the primary damage state and the fate of the produced defects in irradiated metals and semiconductors. We present a review of recent results of molecular dynamics (MD) and kinetic Monte Carlo (KMC) simulations of defect production and annealing in irradiated metals and semiconductors. The MD simulations describe the primary damage state in two prototypical elemental metals and in one-elemental semiconductor, namely Fe, Au, and Si. These materials were all thoroughly investigated by Prof. Kiritani and his colleagues using neutron irradiation followed by TEM observation, and here we attempt to provide some further understanding of the experimental observations by using atomic-scale computer simulation tools. We describe the production of interstitial and vacancy clusters in the cascades and highlight the differences among the various materials. In particular, we discuss how covalent bonding in Si effects defect production and amorphization resulting in a very different primary damage state from the metals. We also use MD simulations to extract prefactors and activation energies for migration of point defects, as well as to investigate the energetics, geometry and diffusivity of small vacancy and interstitial clusters. We show that in the metals, small interstitial clusters are highly mobile and glide in one dimension along the direction of the Burgers vector. The results for the primary damage state and for the defect energetics and kinetics are then combined and used in a KMC simulation to investigate the escape efficiency of defects from their nascent cascade in metals. We show that in fee metals Au and Pb at or above stage V the escape probability is approximately 40% for 30 keV recoils so that the freely migrating defect fraction is approximately 10% of the displacement per atom (dpa) standard. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Cent Res Inst Elect Power Ind, Komae, Tokyo 201, Japan. RP de la Rubia, TD (reprint author), Lawrence Livermore Natl Lab, POB 808,L-268, Livermore, CA 94550 USA. RI Caturla, Maria /D-6241-2012 OI Caturla, Maria /0000-0002-4809-6553 NR 79 TC 12 Z9 12 U1 0 U2 6 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1042-0150 J9 RADIAT EFF DEFECT S JI Radiat. Eff. Defects Solids PY 1999 VL 148 IS 1-4 BP 95 EP 126 DI 10.1080/10420159908229089 PG 32 WC Nuclear Science & Technology; Physics, Fluids & Plasmas; Physics, Condensed Matter SC Nuclear Science & Technology; Physics GA 232GP UT WOS:000082363000010 ER PT J AU Zinkle, SJ AF Zinkle, SJ TI Fundamental radiation effects parameters in metals and ceramics SO RADIATION EFFECTS AND DEFECTS IN SOLIDS LA English DT Article; Proceedings Paper CT Kiritani Symposium on Structural Defects in Advanced Materials CY DEC 18-20, 1996 CL INUYAMA, JAPAN DE ceramics; metals; radiation effects; microstructure; point defect diffusion ID ENERGETIC DISPLACEMENT CASCADES; IRRADIATION-INDUCED CRYSTALLINE; IMPROVED TEMPERATURE CONTROL; BEAM-INDUCED AMORPHIZATION; SIC SINGLE-CRYSTALS; NEUTRON-IRRADIATION; MOLECULAR-DYNAMICS; DEFECT CLUSTERS; ION IRRADIATION; VOID FORMATION AB Several fundamental aspects of defect cluster accumulation in irradiated ceramics and face centered cubic metals are reviewed, with particular emphasis on radiation hardening and the microstructural evolution in Cu observed by transmission electron microscopy (TEM). At temperatures where interstitials are mobile (> 50 K in Cu), the defect cluster density in pure Cu is initially proportional to the dose and exhibits a square root dose dependence above similar to 10(-4) displacements per atom. This fluence dependence (determined from electrical resistivity and TEM studies) helps to resolve a long-standing controversy on the fluence dependence of radiation hardening. The fraction of freely migrating interstitials in copper irradiated with 14 MeV neutrons at room temperature is similar to 11%. The activation energy for annealing stage V (stacking fault tetrahedra evaporation) in neutron-irradiated copper has been measured to be 0.84 eV. Some features of the point defect accumulation behavior in ceramics are found to be very similar to the trends observed in pure Cu, despite the obvious differences in the physical properties of these two types of materials. Finally, microstructural evidence for some processes unique to nonmetals are summarized, particularly ionization induced diffusion. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. OI Zinkle, Steven/0000-0003-2890-6915 NR 158 TC 49 Z9 49 U1 2 U2 24 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1042-0150 EI 1029-4953 J9 RADIAT EFF DEFECT S JI Radiat. Eff. Defects Solids PY 1999 VL 148 IS 1-4 BP 447 EP 477 DI 10.1080/10420159908229104 PG 31 WC Nuclear Science & Technology; Physics, Fluids & Plasmas; Physics, Condensed Matter SC Nuclear Science & Technology; Physics GA 232GP UT WOS:000082363000025 ER PT J AU Garner, FA Toloczko, MB AF Garner, FA Toloczko, MB TI Persistence of microstructural evolution in irradiated metals and its consequences at high radiation exposure SO RADIATION EFFECTS AND DEFECTS IN SOLIDS LA English DT Article; Proceedings Paper CT Kiritani Symposium on Structural Defects in Advanced Materials CY DEC 18-20, 1996 CL INUYAMA, JAPAN DE irradiation; microstructure; void swelling; irradiation creep; mechanical properties; transmutation ID CENTERED-CUBIC METALS; NEUTRON-IRRADIATION; REACTOR IRRADIATION; EBR-II; NICKEL; ALLOYS; CREEP; AISI-316; STEELS; SOLUTE AB A review is presented of a very general aspect of the response of all metals subjected to displacive irradiation. This aspect is referred to as "persistence" and describes the tendency of both radiation-induced microstructural evolution and the associated changes in material properties or dimensional stability to evolve to saturation states that resist further change upon continued irradiation. It is shown that new persistent states can develop on a longer time frame associated with the late-term loss of existing microstructural components or the gain of new components, especially when transmutation and/or segregation occurs. The persistent states are often dependent on the irradiation conditions, and if these are changed, the material usually adjusts to form the persistent state characteristic of the new conditions, with the memory of the former stare often lost, and sometimes leaving no visible record of the former state in the new microstructure. Depending on the microstructural components involved, the transition toward the new persistent state can occur quickly or very slowly. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Garner, FA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 65 TC 4 Z9 4 U1 0 U2 1 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1042-0150 J9 RADIAT EFF DEFECT S JI Radiat. Eff. Defects Solids PY 1999 VL 148 IS 1-4 BP 479 EP 514 DI 10.1080/10420159908229105 PG 36 WC Nuclear Science & Technology; Physics, Fluids & Plasmas; Physics, Condensed Matter SC Nuclear Science & Technology; Physics GA 232GP UT WOS:000082363000026 ER PT J AU Bohm, J Alberts, WG Swinth, KL Soares, CG McDonald, JC Thompson, IMG Kramer, HM AF Bohm, J Alberts, WG Swinth, KL Soares, CG McDonald, JC Thompson, IMG Kramer, HM TI ISO recommended reference radiations for the calibration and proficiency testing of dosemeters and dose rate meters used in radiation protection SO RADIATION PROTECTION DOSIMETRY LA English DT Article ID ANGULAR-DEPENDENCE FACTORS; EQUIVALENT CONVERSION COEFFICIENTS; AIR KERMA; PHOTON BEAMS; PHANTOMS; ROD AB One of the activities of the International Organization for Standardization (ISO) is the preparation and revision of standards specifying the requirements for photon, beta and neutron reference radiations to be used in radiation protection for the calibration of personal and area dosemeters and for contamination monitors. The reference radiations are also specified for determining the response of the instruments as a function of radiation energy and angle of incidence. Radionuclide sources, X ray facilities, reactors and accelerators are utilised as radiation sources to cover the wide range of radiation types and energies. The standards are intended to be applied by primary and secondary standard dosimetry laboratories, but information contained in the standards is widely applicable. The standards specify, in addition, fundamental requirements for an adequate characterisation of reference radiations and describe calibration procedures. The latter include the specification of phantoms (trunk, arm/leg, finger) for the calibration and type testing of personal dosemeters in terms of the operational quantities proposed by the ICRU. Conversion coefficients are provided for all the reference radiations. The present paper gives background information about the concepts of the calibration procedures, the choice of the reference radiations, and their dosimetry. The main features of the standards are described and illustrated by examples. C1 Phys Tech Bundesanstalt, D-38116 Braunschweig, Germany. Swith Associates, Richland, WA USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Bohm, J (reprint author), Phys Tech Bundesanstalt, D-38116 Braunschweig, Germany. NR 32 TC 23 Z9 24 U1 1 U2 3 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 86 IS 2 BP 87 EP 105 PG 19 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 251TD UT WOS:000083460200002 ER PT J AU Kramer, GH Loesch, RM Olsen, PC AF Kramer, GH Loesch, RM Olsen, PC TI The 1993 intercomparison of the measurement of in vivo radioactivity SO RADIATION PROTECTION DOSIMETRY LA English DT Article ID PROGRAM AB The Canadian National Calibration Reference Centre for In-Vivo, Monitoring and the United States Department of Energy collaborated to offer an international intercomparison programme to whole-body counting facilities in 1993. The Human Monitoring Laboratory fabricated a phantom shell corresponding to a reference four-year-old child and Battelle Pacific Northwest National Laboratory filled the shell with radioactive tissue substitute polyurethane to simulate a uniform natural radioactivity and fission product distribution in soft tissues (K-40,Y-88,Cs-137). Participants were not informed of the radioactive content and were asked to determine the identity and amount of the radionuclides in the energy range 200-2000 keV. Although all nuclides were identified correctly, most participants reported activities for Y-88 and Cs-137 only. Each facility was asked to make an estimate of the 'worst case' precision and estimate their minimum detectable activity. The programme had 35 participants from 18 countries for a total of 43 counting systems. The programme began in April 1993 and ended on 1 Aug. 1995. The intercomparison has shown that all whole-body counters are phantom-size dependent and that size-dependent calibration factors should be used. The scanning bed geometry is less size-dependent than the other geometries when only the standard (man-sized) calibration factors are used; however, when applied, size correction factors remove this geometrical advantage and all configurations perform equally well. C1 Radiat Protec Bur, Human Monitoring Lab, Ottawa, ON K1A 1C1, Canada. US DOE, Off Hlth, Dept Energy Lab Accreditat Program, Washington, DC 20585 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Kramer, GH (reprint author), Radiat Protec Bur, Human Monitoring Lab, 775 Brookfield Rd, Ottawa, ON K1A 1C1, Canada. NR 7 TC 5 Z9 5 U1 0 U2 0 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 86 IS 3 BP 197 EP 205 PG 9 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 264TW UT WOS:000084199000007 ER PT J AU Devine, RT Hsu, HH AF Devine, RT Hsu, HH TI Preliminary studies for a high energy neutron area monitor SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB ID DOSIMETER AB Etched track detectors were exposed to neutrons produced by a spallation target struck by a beam of 800 MeV protons. The fields were filtered by 0, 10, and 40 cm of polyethylene. The etched track dosemeters were exposed on a polyethylene phantom. The dosemeters were exposed bare and behind lead filters of 0.25, 0.50, 0.75, 1.00, 1.25 and 1.50 cm of lead with the face of the dosemeter perpendicular to the beam, and bare and behind lead filters of 0.50, 1.0, and 1.5 cm of lead with angles of incidence 45 degrees and 75 degrees. Monte Carlo calculations of these experimental configurations were done using MCNP and LAHET with input from the calculated spectra. These results are compared with the experimental results to understand the basic processes involved in the production of tracks with high energy neutrons and to develop a high energy neutron area monitor. C1 Univ Calif Los Alamos Natl Lab, ESH 4, Los Alamos, NM 87545 USA. RP Devine, RT (reprint author), Univ Calif Los Alamos Natl Lab, ESH 4, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 85 IS 1-4 BP 99 EP 100 PG 2 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KQ UT WOS:000081959400021 ER PT J AU Zummo, JJ Liu, JC AF Zummo, JJ Liu, JC TI Development and testing of a thermoluminescence dosemeter for mixed neutron-photon-beta radiation fields SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB AB A new four-element thermoluminescence (TL) dosemeter and dose evaluation algorithm have been developed and tested to better characterise personnel exposure in mixed neutron-photon-beta radiation fields. The prototype dosemeter is based on a commercially available TL card (with three (LiF)-Li-7 chips and one (LiF)-Li-6 chip) and modified filtration elements. The new algorithm takes advantage of the high temperature peak characteristics of the (LiF)-Li-6 element to quantify the neutron dose component better. The dosemeter was tested in various radiation fields, consisting of mixtures of two radiation types typically used for dosemeter performance testing, as well as mixtures of three radiation types to simulate possible exposure conditions. The new dosemeter gave superior performance, based on the tolerance levels, when using the new algorithm as compared to a conventional algorithm that did not use the high temperature peak methodology. The limitations and further improvements are discussed. C1 Genentech Inc, S San Francisco, CA 94080 USA. SLAC, Stanford, CA 94309 USA. RP Zummo, JJ (reprint author), Genentech Inc, 1 DNA Way, S San Francisco, CA 94080 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 85 IS 1-4 BP 141 EP 144 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KQ UT WOS:000081959400032 ER PT J AU Klemic, G Shobe, J Sengupta, S Shebell, P Miller, K Carolan, PT Holeman, G Kahnhauser, H Lamperti, P Soares, C Azziz, N Moscovitch, M AF Klemic, G Shobe, J Sengupta, S Shebell, P Miller, K Carolan, PT Holeman, G Kahnhauser, H Lamperti, P Soares, C Azziz, N Moscovitch, M TI State of the art of environmental dosimetry: 11th international intercomparison and proposed performance tests SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB AB The eleventh international intercomparison of environmental dosemeters was organised by the Environmental Measurements Laboratory in collaboration with the National Institute of Standards and Technology (NIST) and Brookhaven National Laboratory. One hundred and twenty one participants from 31 countries submitted 174 sets of dosemeters, including thermoluminescence dosemeters (TLDs), film, electrets, and a Geiger-Mueller device. An outdoor field site was used to expose dosemeters to natural radiation for three months, while other dosemeters were exposed to Cs-137 and Am-241 laboratory sources. A pressurised ionisation chamber, operated continuously at the field site, provided an independent measure of the air kerma in the field, and laboratory air kerma values were verified with chambers calibrated by NIST. Results are presented and current issues in environmental dosimetry are highlighted, including the field performance of new hypersensitive TLD materials. Preliminary results are given from a pilot test of a proposed standard from the American National Standards Institute that provides performance test criteria for environmental dosemeters. C1 US DOE, Environm Measurements Lab, New York, NY 10014 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. US Dept Energy, Brookhaven Grp, Upton, NY 11973 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Georgetown Univ, Med Ctr, Washington, DC 20007 USA. RP Klemic, G (reprint author), US DOE, Environm Measurements Lab, 201 Varick St,5th Floor, New York, NY 10014 USA. NR 9 TC 18 Z9 19 U1 0 U2 1 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 85 IS 1-4 BP 201 EP 206 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KQ UT WOS:000081959400045 ER PT J AU Ranogajec-Komor, M Klemic, G Sengupta, S Knezevic, Z Raccah, F Vekic, B AF Ranogajec-Komor, M Klemic, G Sengupta, S Knezevic, Z Raccah, F Vekic, B TI Investigation of the performance of (LiF)-Li-7 : Mg,Cu,P under environmental conditions SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB ID MCP-N; NATURAL RADIATION; TL DETECTORS; RADIOMETRY; LIF-MG,TI; DOSIMETRY; TLD-100 AB The high gamma sensitivity demonstrated by LiF:Mg,Cu,P produced in China and Poland makes it appropriate for environmental applications. Recently a new version of this material has been produced in the United States in both loose chip and encapsulated card form. This study investigates the performance of the US material under conditions designed to simulate environmental insults as described in ANSI Draft Standard N13.29. Twenty dosemeters are placed in an environmental chamber that cycles twice through three 15 day periods of temperature and humidity conditions: -20 degrees C; +50 degrees C with 20% relative humidity; and +50 degrees C with 90% relative humidity. Five randomly selected dosemeters are exposed to a Cs-137 source that will give doses between 0.5 to 10.0 mSv at the beginning, middle, and end of the 90 day test. Two 40 W fluorescent bulbs provide lighting in the chamber. Performance is measured by comparison with the proposed Draft N13.29 performance criteria that would require the absolute value of the bias and standard deviation to each be less than or equal to 0.35, while their sum must be less than or equal to 0.50. C1 Rudjer Boskovic Inst, Zagreb 10000, Croatia. US DOE, Environm Measurements Lab, New York, NY 10014 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ranogajec-Komor, M (reprint author), Rudjer Boskovic Inst, POB 1016,Bijenicka 54, Zagreb 10000, Croatia. NR 18 TC 3 Z9 3 U1 1 U2 1 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 85 IS 1-4 BP 217 EP 222 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KQ UT WOS:000081959400048 ER PT J AU Perry, OR Moscovitch, M Velbeck, KJ Rotunda, JE AF Perry, OR Moscovitch, M Velbeck, KJ Rotunda, JE TI LiF : Mg,Cu,P based environmental dosemeter and dose calculation algorithm SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB AB The development is described of a new environmental TLD dosemeter badge and dose computation algorithm based on the new LiF:Mg,Cu,P material. LiF:Mg,Cu,P, with its high sensitivity, tissue equivalence, energy independence, and low fading characteristics, is a natural choice for environmental dosimetry. The badge consists of a card and a plastic holder. The card contains four LiF:Mg,Cu,P elements encapsulated in Teflon. The elements are all 3.2 mm square and 0.4 mm thick. The badge is symmetrical and uses four filters to discriminate low and high energy photons and to determine directional dose equivalent, H'(0.07,alpha), and ambient dose equivalent, H*(10). Extensive data were taken based on irradiations of 920 dosemeters to both single and mixed fields of photons and betas. In addition, angular incidence data of various fields were taken. The approach to the algorithm is empirical and is based on these data. While most algorithms are based solely on perpendicular incidence exposure, this algorithm is being developed to account for the angular response of the dosemeter. The algorithm for perpendicular irradiation is presented. The angular incidence portion of the algorithm is in development. The dosemeter is designed to meet the criteria of the new draft standard ANSI N13.29, 'Environmental Dosimetry Performance - Criteria for Testing'. C1 Lockheed Martin Idaho Technol Co, Idaho Falls, ID 83415 USA. Georgetown Univ, Sch Med, Dept Radiat Med, Washington, DC 20007 USA. BICRON NE, Solon, OH 44139 USA. RP Perry, OR (reprint author), Lockheed Martin Idaho Technol Co, POB 1625, Idaho Falls, ID 83415 USA. NR 8 TC 6 Z9 6 U1 0 U2 1 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 85 IS 1-4 BP 273 EP 281 PG 9 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KQ UT WOS:000081959400060 ER PT J AU Espinosa, G Gammage, RB AF Espinosa, G Gammage, RB TI Radon distribution inside dwellings in Mexico SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB ID INDOOR RADON; LUNG-CANCER AB The Rn-222 concentration level has been surveyed inside dwellings in the seven more important and populated cities of Mexico, and the results are presented in this work. The measurements were mad for six months, covering winter and spring, the coolest seasons of the year in Mexico. More than a hundred dwellings in each town were chosen, selecting three groups of basic architectonic styles. Different factors affecting the potential Rn-222 concentration were considered in the study: construction materials, age of the dwellings, wall coverings, location of sites, and meteorological parameters such as indoor-outdoor temperature and relative environmental humidity. The passive integration of radon measurement method based on nuclear tracks was used. The closed end cup device, developed at the Institute of Physics of the University of Mexico, with CR-39 polycarbonate as material detector was chosen. The measurement methodology consists of the one step chemical etching process to develop the nuclear tracks and automatic track reading by a digital image analyser. C1 Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Espinosa, G (reprint author), Univ Nacl Autonoma Mexico, Inst Fis, Apdo Postal 20-364, Mexico City 01000, DF, Mexico. NR 8 TC 3 Z9 3 U1 1 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 85 IS 1-4 BP 325 EP 327 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KQ UT WOS:000081959400071 ER PT J AU Olko, P Bilski, P Budzanowski, M Waligorski, MPR Fasso, A Ipe, N AF Olko, P Bilski, P Budzanowski, M Waligorski, MPR Fasso, A Ipe, N TI Modelling of the thermoluminescence response of LiF : Mg,Cu,P (MCP-N) detectors after doses of low energy photons SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB ID MICRODOSIMETRIC INTERPRETATION; DOSIMETRY; EFFICIENCY; RADIATION AB A simple numerical approach has been developed to predict the relative (to Cs-137 gamma rays) response of LiF:Mg,Cu P (MCP-N) thermoluminescence detectors after doses of photons in the energy range from 4 to 1000 keV. The following major factors influencing the TL detector response were taken into account: (i) mass energy absorption coefficients for LiF:Mg,Cu,P and air; (ii) attenuation of low energy X rays in a thick TL detector; (iii) self-absorption of thermoluminescence light in a thick detector; and (iv) the relative TL efficiency (intrinsic luminous efficiency), eta, of MCP-N detectors, which depends strongly on the photon energy via radiation ionisation density. The values of eta were calculated using the microdosimetric one-hit detector model and fitted with the function eta = 0.794 - exp [-(E[keV]-4.663)/9.69] over the range of photon energies, 4 keV < E < 40 keV. The results of model calculations agree well with experimental values of eta measured in the energy range 6-18 keV at SLAG using monoenergetic synchrotron radiation and with literature data for higher energies. This approach may be useful in practical applications of MCP-N detectors in X ray dosimetry, such as TL dosimetry of mammography units. C1 Inst Nucl Phys, PL-31342 Krakow, Poland. Ctr Oncol, PL-30115 Krakow, Poland. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94070 USA. RP Olko, P (reprint author), Inst Nucl Phys, Ul Radzikowskiego 152, PL-31342 Krakow, Poland. RI Bilski, Pawel/G-5465-2012 OI Bilski, Pawel/0000-0002-0560-3404 NR 13 TC 19 Z9 19 U1 0 U2 3 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 84 IS 1-4 BP 103 EP 108 PN 1 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 219BF UT WOS:000081587500027 ER PT J AU Ipe, NE Fasso, A Kase, KR Kaur, R Bilski, P Olko, P AF Ipe, NE Fasso, A Kase, KR Kaur, R Bilski, P Olko, P TI Characterisation of the low energy X ray response of Polish TLDs to synchrotron radiation and the determination of some TLD quantities SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Dosimetry CY JUL 05-10, 1998 CL BURGOS, SPAIN SP Bicron Technol, Bubble Technol Ind, Caja Burgos, Comis Interminist Cienc & Tecnolog, Consejo Seguridad Nucl, Direcc Gen Investigacion Cienc & Tecnol, Empressa Nacl Residuos SA, Excmo Ayuntamiento Burgos, Excma Diputac Province Burgos, Landauer Inc, Nucl Technol Publishing, Siemens Environm Syst Ltd, Stillwater Sci LLC, Studsvik Instrument AB ID LIFMG,CU,P AB The responses of the Polish TLDs, MTS-N and MCP-N, are reported. Relative to Cs-137 gamma rays, the response of MTS-N ((LiF)-Li-nat:Mg,Ti - 0.04 cm thick) increased from 0.4 to 1.4 between X ray energies of 6 and 30 keV, and that of MCP-N ((LiF)-Li-nat:Mg, Cu, P - 0.04 cm thick) increased from 0.2 to 1.2 between 6 and 26 keV. A mathematical model for TLD response was used with measured responses to determine overall TLD efficiency, CO(), and efficiency relative to Cs-137. The effective energy attenuation coefficient mu(k) and light attenuation coefficient f were also determined experimentally. The relative efficiency of MTS-N increased from 0.66 to 1.30 between 6 and 30 keV and that of MCP-N increased from 0.37 to 0.99 between 6 and 26 keV. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94070 USA. Inst Nucl Phys, Hlth Phys Lab, Krakow, Poland. RP Ipe, NE (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94070 USA. RI Bilski, Pawel/G-5465-2012 OI Bilski, Pawel/0000-0002-0560-3404 NR 7 TC 8 Z9 8 U1 0 U2 0 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 84 IS 1-4 BP 169 EP 173 PN 1 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 219BF UT WOS:000081587500041 ER PT J AU Mahaffey, JA Alavanja, MCR Parkhurst, MA Berger, E Brownson, RC AF Mahaffey, JA Alavanja, MCR Parkhurst, MA Berger, E Brownson, RC TI Estimation of radon exposure history for analysis of a residential epidemiological study SO RADIATION PROTECTION DOSIMETRY LA English DT Article ID LUNG-CANCER; NONSMOKING WOMEN; INDOOR RADON; PAST EXPOSURE; RISK; MISSOURI; CR-39; GLASS AB Traditional methods for assessing radon exposure in epidemiological studies have used current ambient detector measurements as surrogates for concentrations decades ago in past residences occupied by study subjects. Substantial temporal and spatial variability has been found which challenges the validity of this practice. As an alternative, CR-39 surface monitors were attached to selected glass objects to measure alpha emissions from radon progeny and infer past exposures of subjects. The validity of the use of surface monitors to detect alpha emissions in glass was successfully demonstrated by comparing results of these monitors with pulse ionisation chamber measurements. Subsequently, surface monitor and ambient detector results were compared, and factors such as household smoking and use of windows for measurement were examined. Individually, both the surface monitor and the ambient detector methodologies each gave highly repeatable results (Pearson product-moment correlations of 0.81 and 0.97, respectively), but the consistency between the two technologies was only satisfactory (correlation of 0.53). C1 Pacific NW Lab, Richland, WA 99352 USA. NCI, Bethesda, MD 20814 USA. Informat Management Serv Inc, Silver Spring, MD 20904 USA. St Louis Univ, Sch Publ Hlth, St Louis, MO 63108 USA. RP Mahaffey, JA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 18 TC 11 Z9 11 U1 0 U2 1 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 83 IS 3 BP 239 EP 247 PG 9 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KP UT WOS:000081959300006 ER PT J AU Liu, JC Ng, TT AF Liu, JC Ng, TT TI Monte Carlo calculations using MCNP4B for an optimal shielding design for a 14 MeV neutron source SO RADIATION PROTECTION DOSIMETRY LA English DT Article AB The shielding for 14 MeV neutrons from a D-T generator at SLAG needs to be optimised in terms of shield thickness and cost. Shielding calculations were made using the MCNP4B Monte Carlo code and the ENDF/B-VI cross section set. The following materials were studied: iron, berated polyethylene, three types of normal and heavy concrete, and combinations of iron and berated polyethylene. The effects of shielding geometry (sphere, cube, and the proposed geometry) were also examined. The results of the transmission factor for ambient dose equivalent, as well as the attenuation lengths and the average energies, for neutrons and gammas outside the shielding are presented. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Liu, JC (reprint author), Stanford Linear Accelerator Ctr, MS 48,POB 4349, Stanford, CA 94309 USA. NR 6 TC 3 Z9 3 U1 0 U2 3 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 83 IS 3 BP 257 EP 262 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 225KP UT WOS:000081959300008 ER PT J AU Miller, G Inkret, WC Martz, HF AF Miller, G Inkret, WC Martz, HF TI Internal dosimetry intake estimation using Bayesian methods SO RADIATION PROTECTION DOSIMETRY LA English DT Article ID INHALED (PUO2)-PU-238 AB New methods for the inverse problem of internal dosimetry are proposed based on evaluating expectations of the Bayesian posterior probability distribution of intake amounts, given bioassay measurements. These expectation integrals are normally of very high dimension and hence impractical to use. However, the expectations can be algebraically transformed into a sum of terms representing different numbers of intakes, with a Poisson distribution of the number of intakes. This sum often rapidly converges, when the average number of intakes for a population is small. A simplified algorithm using data unfolding is described (UF code). C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 25 TC 26 Z9 26 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 EI 1742-3406 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 82 IS 1 BP 5 EP 17 PG 13 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 175NE UT WOS:000079099900002 ER PT J AU Rajagopal, V Mathiyarasu, R Danalakshmi, B Sreedevi, KR Kramer, GH Olsen, PC Loesch, RM AF Rajagopal, V Mathiyarasu, R Danalakshmi, B Sreedevi, KR Kramer, GH Olsen, PC Loesch, RM TI Performance of whole-body counters at IGCAR in an intercomparison exercise SO RADIATION PROTECTION DOSIMETRY LA English DT Article AB The Canadian National Calibration Reference Centre for in vivo Monitoring (NCRC), and United States Department of Energy (USDOE) periodically conduct intercalibration and intercomparison exercises with the aim of evaluating the relative performances of whole-body counting systems in various countries. In continuation of their earlier exercises they initiated another exercise in 1996. The exercise consists of identifying and quantifying the unknown radionuclides deliberately included inside the phantom chosen for calibration. The exercise was carried out with a resin-filled, ICRP standard, adult female BOMAB phantom. Each participating laboratory was given seven days for measurement and evaluation of the results irrespective of the number of counting systems they possessed. Health and Safety Division (HASD), Indira Gandhi Centre for Atomic Research (IGCAR) received the phantom during April 1997 and correctly identified the radionuclides. The activity estimate has a bias of 3% and a measurement precision better than 1%. It is interesting to see such close agreement in the prediction of activity of the radionuclides, even though the whole-body counting systems are calibrated with a masonite cut-sheet phantom whose size, shape and weight are quite different from that of the BOMAB phantom used in the present exercise. The details of the exercise, the phantom used, the measurements made and the results obtained are discussed. C1 Indira Gandhi Ctr Atom Res, Radiat Safety Sect, Div Hlth & Safety, Safety Res & Hlth Phys Grp, Kalpakkam 603102, Tamil Nadu, India. Radiat Protect Bur, Human Monitoring Lab, Ottawa, ON, Canada. Pacific NW Lab, Richland, WA 99352 USA. US DOE, Off Hlth, Washington, DC 20585 USA. RP Rajagopal, V (reprint author), Indira Gandhi Ctr Atom Res, Radiat Safety Sect, Div Hlth & Safety, Safety Res & Hlth Phys Grp, Kalpakkam 603102, Tamil Nadu, India. NR 7 TC 3 Z9 3 U1 0 U2 0 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 82 IS 1 BP 19 EP 23 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 175NE UT WOS:000079099900003 ER PT J AU Sonder, E Ahmed, AB Watson, EA AF Sonder, E Ahmed, AB Watson, EA TI An assessment of using glow curve fitting procedures for obtaining information on exposure history SO RADIATION PROTECTION DOSIMETRY LA English DT Article AB A detailed analysis has been performed of the usefulness of grow peak area ratios to determine when, during a dosemeter assignment period, an exposure has taken place. Several heating rates, including the fast rates usually used in routine dosimetry, have been used to quantify the impact of heating rate on such analysis. Large differences in glow peak positions and smaller changes in peak widths resulted from different heating rates. The results indicate that curve fitting techniques and determination of peak area ratios to determine exposure history have very limited usefulness at heating rates generally used in routine dosimetry. C1 Oak Ridge Natl Lab, Off Radiat Protect, Oak Ridge, TN 37831 USA. RP Sonder, E (reprint author), Oak Ridge Natl Lab, Off Radiat Protect, Oak Ridge, TN 37831 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU NUCLEAR TECHNOLOGY PUBL PI ASHFORD PA PO BOX 7, ASHFORD, KENT, ENGLAND TN23 1YW SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 1999 VL 81 IS 4 BP 265 EP 270 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 168AY UT WOS:000078669000004 ER PT J AU Coderre, JA Morris, GM AF Coderre, JA Morris, GM TI The radiation biology of boron neutron capture therapy SO RADIATION RESEARCH LA English DT Review ID RAT SPINAL-CORD; CENTRAL-NERVOUS-SYSTEM; BRAIN-BARRIER DISRUPTION; P-BORONOPHENYLALANINE; BOROCAPTATE SODIUM; B-10(N,ALPHA)LI-7 REACTION; ION MICROSCOPY; IN-VITRO; INTRACEREBRAL MELANOMA; INTRACAROTID INJECTION AB Boron neutron capture therapy (BNCT) is a targeted radiation therapy that significantly increases the therapeutic ratio relative to conventional radiotherapeutic modalities. BNCT is a binary approach: A boron-10 (B-10)-labeled compound is administered that delivers high concentrations of B-10 to the target tumor relative to surrounding normal tissues. This is followed by irradiation with thermal neutrons or epithermal neutrons which become thermalized at depth in tissues. The short range (5-9 mu m) of the alpha and Li-7 particles released from the B-10(n,alpha)Li-7 neutron capture reaction make the microdistribution of B-10 of critical importance in therapy. The radiation field in tissues during BNCT consists of a mixture of components with differing LET characteristics. Studies have been carried out in both normal and neoplastic tissues to characterize the relative biological effectiveness of each radiation component. The distribution patterns and radiobiological characteristics of the two B-10 delivery agents in current clinical use, the amino acid p-boronophenylalanine (BPA) and the sulfhydryl borane (BSI), have been evaluated in a range of normal tissues and tumor types. Considered overall, BSH-mediated BNCT elicits proportionately less damage to normal tissue than does BNCT mediated with BPA. However, BPA exhibits superior in vivo tumor targeting and has proven much more effective in the treatment of brain tumors in rats. In terms of fractionation effects, boron neutron capture irradiation modalities are comparable with other high-LET radiation modalities such as fast-neutron therapy. There was no appreciable advantage in increasing the number of daily fractions of thermal neutrons beyond two with regard to sparing of normal tissue in the rat spinal cord model. The experimental studies described in this review constitute the radiobiological basis for the new BNCT clinical trials for glioblastoma at Brookhaven National Laboratory, at the Massachusetts Institute of Technology, and at the High Flux Reactor, Petten, The Netherlands. The radiobiology of experimental and clinical BNCT is discussed in detail. (C) 1999 by Radiotion Research Society. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Oxford, Churchill Hosp, Inst Res, Oxford OX3 7LJ, England. RP Coderre, JA (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 125 TC 312 Z9 318 U1 5 U2 45 PU RADIATION RESEARCH SOC PI LAWRENCE PA 810 E TENTH STREET, LAWRENCE, KS 66044 USA SN 0033-7587 EI 1938-5404 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 1 EP 18 DI 10.2307/3579742 PG 18 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400001 PM 9973079 ER PT J AU Evans, TM Wang, CKC AF Evans, TM Wang, CKC TI Measurement of distributions of small-scale energy depositions from low-linear energy transfer particles using the superheated drop detector SO RADIATION RESEARCH LA English DT Article ID INDUCED CAVITATION PROCESS; SMALL CYLINDRICAL TARGETS; ULTRASOFT X-RAYS; TRACK STRUCTURE; ELECTRONS; LIQUID; WATER AB We have developed a new detection method for measuring distributions of energy depositions from particles characterized by low linear energy transfers (LETs). In particular, we have developed a detection system to measure energy depositions produced by electrons and photons on nanometer scales. The detector is based upon the operational principles of the superheated drop detector (SDD). SDDs consist of tiny droplets of superheated liquid suspended within a gel-like emulsion. The SDDs in this study are fabricated using Freon-115 and a glycerol-based gel as the superheated liquid and host medium. This SDD configuration is operated as a threshold temperature-dependent detector for measuring nanoscopic distributions of energy depositions from low-LET particles. Measured results are compared to the calculated distributions of energy depositions along an electron track. A new electron track code, ESLOW3.1, is used to perform the computational study, Measurements show good agreement with computational results in the energy deposition range of 40-200 eV, (C) 1999 by Radiation Research Society. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Georgia Inst Technol, Nucl Engn Program, Atlanta, GA 30332 USA. RP Evans, TM (reprint author), Univ Calif Los Alamos Natl Lab, X-TM MS D409, Los Alamos, NM 87545 USA. NR 28 TC 6 Z9 6 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 19 EP 30 DI 10.2307/3579743 PG 12 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400002 PM 9973080 ER PT J AU Lucas, JN Deng, W Oram, SW Hill, FS Durante, M George, K Wu, H Owens, CL Yang, T AF Lucas, JN Deng, W Oram, SW Hill, FS Durante, M George, K Wu, H Owens, CL Yang, T TI Theoretical and experimental tests of a chromosomal fingerprint for densely ionizing radiation based on F ratios calculated from stable and unstable chromosome aberrations SO RADIATION RESEARCH LA English DT Article ID DIRECT BIOLOGICAL EVIDENCE; HIROSHIMA ATOMIC-BOMB; HUMAN-LYMPHOCYTES; IN-SITU; PERICENTRIC INVERSIONS; ALPHA-PARTICLES; CENTRIC RINGS; ACUTE-X; IRRADIATION; HYBRIDIZATION AB In the present study, F ratios for both stable chromosome aberrations, i.e. ratios of translocations to pericentric inversions, and unstable aberrations, i.e. dicentrics and centric rings, were measured using fluorescence in situ hybridization. F ratios for stable aberrations measured after exposure to low (2.89 Gy Co-60 gamma rays) and high-LET (0.25 Gy Fe-56 ions; 1.25 Gy Fe-56 ions; 3.0 Gy C-12 ions) radiation were 6.5 +/- 1.5, 4.7 +/- 1.6, 9.3 +/- 2.5 and 10.4 +/- 3.0, respectively. F ratios for unstable aberrations measured after low (2.89 Gy Co-60 gamma rays) and high-LET (0.25 Gy Fe-56 ions; 3.0 Gy C-12 ions) radiations were 6.5 +/- 1.6, 6.3 +/- 2.3 and 11.1 +/- 3.7, respectively. No significant difference between the F ratios for low- and high-LET radiation was found. Further tests on the models for calculation of the F ratio proposed by Brenner and Sachs (Radiat. Res. 140, 134-142, 1994) showed that the F ratio may not be straightforward as a practical fingerprint for densely ionizing radiation. (C) 1999 by Radiation Research Society. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sichuan Inst Radiat Hlth & Protect, Sichuan Inst Occupat Hlth, Chengdu 610041, Peoples R China. Univ Naples Federico II, Dipartimento Sci Fisiche, I-80125 Naples, Italy. NASA, Lyndon B Johnson Space Ctr, Div Med Sci, Houston, TX 77058 USA. RP Lucas, JN (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Deng, Wen/C-4154-2009; Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 44 TC 14 Z9 17 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 85 EP 91 DI 10.2307/3579752 PG 7 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400011 PM 9973089 ER PT J AU Mendelsohn, ML AF Mendelsohn, ML TI Dose response, temporal response and biologically based models in the bridge between human and rodent carcinogenesis SO RADIATION RESEARCH LA English DT Meeting Abstract C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 93 EP 93 PG 1 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400013 ER PT J AU Fry, RJM AF Fry, RJM TI Extrapolation of risk estimates across species SO RADIATION RESEARCH LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 94 EP 95 PG 2 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400014 ER PT J AU Ostrouchov, G AF Ostrouchov, G TI Accounting for bias and measurement error in occupational studies SO RADIATION RESEARCH LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 107 EP 108 PG 2 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400026 ER PT J AU Morgan, WF AF Morgan, WF TI The use of chromosome rearrangements to evaluate genomic instability SO RADIATION RESEARCH LA English DT Meeting Abstract ID IONIZING-RADIATION C1 Univ Calif San Francisco, San Francisco, CA 94143 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 111 EP 112 PG 2 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400030 ER PT J AU Kronenberg, A AF Kronenberg, A TI Genomic instability, cell death and mutagenesis SO RADIATION RESEARCH LA English DT Meeting Abstract ID DELAYED REPRODUCTIVE DEATH; SURVIVING X-IRRADIATION; GENE-MUTATIONS; RADIATION; FREQUENCY; PHENOTYPE C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 113 EP 114 PG 2 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400032 ER PT J AU Goodwin, E Lehnert, BE AF Goodwin, E Lehnert, BE TI Bystander effects of radiation: Mechanisms of action and significance in risk assessment SO RADIATION RESEARCH LA English DT Meeting Abstract ID SISTER-CHROMATID EXCHANGES; ALPHA-PARTICLES; CLASTOGENIC ACTIVITY; HUMAN-CELLS; INSTABILITY; CULTURES; PLASMA; RADON C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 1999 VL 151 IS 1 BP 114 EP 116 PG 3 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 154VQ UT WOS:000077910400033 ER PT S AU Sale, KE Bergstrom, P Buck, R Cullen, D Fujino, D Hartmann-Siantar, C AF Sale, KE Bergstrom, P Buck, R Cullen, D Fujino, D Hartmann-Siantar, C CA Monte Carlo Radiation Transport Grp BE Morton, EJ TI Overview and applications of the Monte Carlo radiation transport tool kit at LLNL SO RADIATION SOURCES AND RADIATION INTERACTIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1st Conference on Radiation Sources and Radiation Interactions CY JUL 18-23, 1999 CL DENVER, CO SP SPIE AB Modem Monte Carlo radiation transport codes can be applied to model most applications of radiation, fi-om optical to TeV photons, from thermal neutrons to heavy ions. Simulations can include any desired level of detail in three-dimensional geometries using the right level of detail in the reaction physics. The technology areas to which we have applied these codes include medical applications, defense, safety and security programs, nuclear safeguards and industrial and research system design and control. The main reason such applications are interesting is that by using these tools substantial savings of time and effort (i.e. money) can be realized. In addition it is possible to separate out and investigate computationally effects which can not be isolated and studied in experiments. In model calculations, just as in real life, one must take care in order to get the correct answer to the right question. Advancing computing technology allows extensions of Monte Carlo applications in two directions. First, as computers become more powerful more problems can be accurately modeled. Second, as computing power becomes cheaper Monte Carlo methods become accessible more widely. An overview of the set of Monte Carlo radiation transport tools in use a LLNL will be presented along with a few examples of applications and future directions. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sale, KE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 1 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3257-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3771 BP 74 EP 79 DI 10.1117/12.363708 PG 6 WC Optics; Physics, Applied SC Optics; Physics GA BN88C UT WOS:000083314200008 ER PT S AU Daemen, LL Seeger, PA Hjelm, RP Thelliez, TG AF Daemen, LL Seeger, PA Hjelm, RP Thelliez, TG BE Morton, EJ TI Monte Carlo tool for neutron optics and neutron scattering instrument design SO RADIATION SOURCES AND RADIATION INTERACTIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1st Conference on Radiation Sources and Radiation Interactions CY JUL 18-23, 1999 CL DENVER, CO SP SPIE DE Monte Carlo; neutron scattering; neutron optics; simulations AB Unlike x-ray generators, neutron sources have inherently low brightness, and care must be exerted in the design of neutron scattering instruments and their coupling to the source to ensure optimal use of the beam. We present a general, versatile Monte Carlo tool for the computer simulation of neutron optics and neutron scattering instruments that allows a user to produce computer models of an instrument and study its performance quantitatively. The Neutron Instrument Simulation Package (NISP) implements a wide range of neutron optics models to describe neutron transport (including gravity) and scattering in the elements making up the instrument. The program is freely available on the world-wide web at http://strider.lansce.lanl.gov/NISP/Welcome.html C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Daemen, LL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 5 TC 8 Z9 8 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3257-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3771 BP 80 EP 89 DI 10.1117/12.363709 PG 10 WC Optics; Physics, Applied SC Optics; Physics GA BN88C UT WOS:000083314200009 ER PT S AU Buck, RM Hall, JM AF Buck, RM Hall, JM BE Morton, EJ TI Applications of the COG multiparticle Monte Carlo transport code to simulated imaging of complex objects SO RADIATION SOURCES AND RADIATION INTERACTIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1st Conference on Radiation Sources and Radiation Interactions CY JUL 18-23, 1999 CL DENVER, CO SP SPIE DE Monte Carlo; radiation transport; simulated radiography; nonintrusive inspection; neutron imaging AB COG is a major multiparticle simulation code in the LLNL Monte Carlo radiation transport toolkit. It was designed to solve deep-penetration radiation shielding problems in arbitrarily complex 3D geometries, involving coupled transport of photons, neutrons, and electrons. COG was written to provide as much accuracy as the underlying cross-sections will allow, and has a number of variance-reduction features to speed computations. Recently COG has been applied to the simulation of high-resolution radiographs of complex objects and the evaluation of contraband detection schemes. In this paper we will give a brief description of the capabilities of the COG transport code and show several examples of neutron and gamma-ray imaging simulations. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Buck, RM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,MS L-59, Livermore, CA 94550 USA. NR 5 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3257-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3771 BP 127 EP 134 DI 10.1117/12.363699 PG 8 WC Optics; Physics, Applied SC Optics; Physics GA BN88C UT WOS:000083314200014 ER PT S AU Batchelor, DB AF Batchelor, DB BE Bernabei, S Paoletti, F TI Prospects for advanced RF theory and modeling SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID ELECTROMAGNETIC-WAVES; PLASMA; PROPAGATION C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Batchelor, DB (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 15 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 3 EP 17 PG 15 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800001 ER PT S AU Phillips, CK Bell, M Bell, RE Bernabei, S Fredrickson, E Hosea, JC LeBlanc, BP Majeski, R Medley, S Ono, M Schilling, G Synakowski, E Taylor, G Wilson, JR AF Phillips, CK Bell, M Bell, RE Bernabei, S Fredrickson, E Hosea, JC LeBlanc, BP Majeski, R Medley, S Ono, M Schilling, G Synakowski, E Taylor, G Wilson, JR CA TFTR Team BE Bernabei, S Paoletti, F TI RF physics in Deuterium-Tritium plasmas SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID ION-CYCLOTRON RANGE; CURRENT DRIVE; EDGE TURBULENCE; RESONANCE; TOKAMAK; FUSION; WAVES AB A wide variety of potential ICRF heating scenarios relevant for the deuterium-tritium plasmas expected in tokamak reactor-class devices were explored in the TFTR and JET programs. Key physics results from the two programs are discussed. C1 Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. RP Phillips, CK (reprint author), Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. NR 22 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 69 EP 78 PG 10 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800006 ER PT S AU Hosea, JC Bernabei, S LeBlanc, BP Majeski, R Phillips, CK Schilling, G Wilson, JR AF Hosea, JC Bernabei, S LeBlanc, BP Majeski, R Phillips, CK Schilling, G Wilson, JR CA TFTR Team BE Bernabei, S Paoletti, F TI The development of RF heating of magnetically confined deuterium-tritium plasmas SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID WAVES; IONS AB The experimental and theoretical development of ion cyclotron radiofrequency heating (ICRF) in toroidal magnetically-confined plasmas recently culminated with the demonstration of ICRF heating of D-T plasmas, first in the Tokamak Fusion Test Reactor (TFTR) and then in the Joint European Torus (JET). Various heating schemes based on the cyclotron resonances between the plasma ions and the applied ICRF waves have been used, including second harmonic tritium, minority deuterium, minority helium-3, mode conversion at the D-T ion-ion hybrid layer,and and ion Bemstein wave heating. Second harmonic tritium heating was first shown to be effective in a reactor-grade plasma in TFTR. D-minority heating on JET has led to the achievement of Q = 0.22, the ratio of fusion power produced to RF power input, sustained over a few energy confinement times. In this paper, some of the key building blocks in the development of rf heating of plasmas are reviewed and prospects for the development of advanced methods of plasma control based on the application of rf waves are discussed. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Hosea, JC (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 19 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 104 EP 107 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800010 ER PT S AU Bernabei, S Gorelenkov, NN Budny, R Fredrickson, ED Hosea, JC Majeski, R Phillips, CK Wilson, JR AF Bernabei, S Gorelenkov, NN Budny, R Fredrickson, ED Hosea, JC Majeski, R Phillips, CK Wilson, JR BE Bernabei, S Paoletti, F TI Role of Alfven instabilities in energetic ion transport. SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB Experiments with plasma heating by waves at the ion cyclotron resonance of a minority species have shown that the heating efficiency degrades above a certain power threshold It is found that this threshold is due to the destabilization of shear Alfven waves, which causes loss of fast ions. There are two distinct regimes characterized by low q(a) and high q(a). In the first case, the fast ion distribution created by ICRF, lies entirely inside r(q=1), away from the location of global TAE. This situation leads to the formation of a very strong fast ion population which stabilizes the sawteeth, but also excites Energetic Particle Modes (EPM), which transport fast ions outside r(q=1) causing the giant crash. At higher q(a), the widening of the Alfven gap due to the steeper q profile, brings the global TAE "in contact" with the fast ion distribution. This results in an immediate and continuous depletion of fast ions from the core, which prevents the formation of the monster sawtooth and the excitation of EPM. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Bernabei, S (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 108 EP 111 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800011 ER PT S AU Fredrickson, E Van Dam, JW Budny, RV Darrow, D Fu, GY Hosea, J Phillips, CK Wilson, JR AF Fredrickson, E Van Dam, JW Budny, RV Darrow, D Fu, GY Hosea, J Phillips, CK Wilson, JR BE Bernabei, S Paoletti, F TI Observation of modes at frequencies near the second Alfven gap in TFTR SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB Modes have been observed near the frequency of the second Alfven gap during off-axis H-minority heating experiments on TFTR, The observation of these modes is surprising in that the second gap, which is generally opened with ellipticity, is expected to be small, of order (r/R)(2), since TFTR plasmas are circular in cross-section. A model is proposed in which the second gap is opened by the fast ion beta, which is shown to be able to introduce mode coupling, much as toroidal effects introduce mode coupling for Toroidal Alfven Eigenmodes (TAE). The modes are seen with and without accompanying TAE mode activity. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Fredrickson, E (reprint author), Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 112 EP 115 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800012 ER PT S AU Wilson, JR Bernabei, S Carter, M Ellis, R Hosea, JC LeBlanc, B Majeski, R Menard, J Phillips, CK Ryan, P Schilling, G Swain, D AF Wilson, JR Bernabei, S Carter, M Ellis, R Hosea, JC LeBlanc, B Majeski, R Menard, J Phillips, CK Ryan, P Schilling, G Swain, D BE Bernabei, S Paoletti, F TI High Harmonic Fast Wave heating and current drive on NSTX - System and experimental plan SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB For the National Spherical Toms Experiment (NSTX) device, High Harmonic Fast Wave (HHFW) heating has been selected for its strong single pass absorption on electrons as the initial heating and current drive scenario. A frequency of 30MHz has been selected (f similar to 16 f(ed)) The waves will be launched into the plasma from a twelve element phased antenna array. Six transmitters will feed the elements in pairs of six independently phasable subsections. Modeling predicts strong single pass damping (>40%) for temperatures as low as 250 eV. As the ion temperature is increased ion damping may compete with the electron absorption for ion temperatures > 1.5 keV. Experiments will be aimed at demonstrating HHFW heating of a small aspect ratio device leading towards the goal of fully non-inductive operation. In the first year of operation the HHFW system will be brought into operation and plasma heating under a variety of plasma conditions will be explored. In the second year, when current drive diagnostics are expected to be available, an exploration of HHFW current drive will begin. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Wilson, JR (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 2 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 168 EP 171 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800026 ER PT S AU Wong, KL Lin-Liu, YR Luce, TC Prater, R AF Wong, KL Lin-Liu, YR Luce, TC Prater, R BE Bernabei, S Paoletti, F TI The effect of toroidal plasma rotation on electron cyclotron current drive efficiency SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID TRANSPORT AB In plasmas with toroidal rotation, the ions are pushed towards the low-field side of the torus by the centrifugal force. An electrostatic potential is set up to maintain charge neutrality which tends to attract electrons towards the low-field side of the torus. Due to this electrostatic potential, the trapped/passing boundary in the electron velocity space changes from a cone for stationary plasmas to an hyperboloid in a rotating plasma. This reduces the phase space for passing electrons. This paper attempts to address rotation effects on the electron cyclotron current drive efficiency. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Wong, KL (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 257 EP 260 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800040 ER PT S AU Majeski, R Menard, J Batchelor, D Bigelow, T Carter, MD Finkenthal, M Jaeger, EF Jones, B Kaita, R Mau, TK Munsat, T Ono, M Phillips, CK Ryan, P Stutman, D Swain, D Wilson, JR AF Majeski, R Menard, J Batchelor, D Bigelow, T Carter, MD Finkenthal, M Jaeger, EF Jones, B Kaita, R Mau, TK Munsat, T Ono, M Phillips, CK Ryan, P Stutman, D Swain, D Wilson, JR BE Bernabei, S Paoletti, F TI RF experiments on spherical torus plasmas SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID RADIOFREQUENCY AB Experimental operations are about to begin an the next generation of spherical tarus (ST) devices - the National Spherical Toms eXperiment (NSTX) in the U.S. and the Mega-Amp Spherical Torus (MAST) in the U.K. The application of RF heating and current drive to these high beta, compact confinement devices is a challenging problem. The initial focus for NSTX had been on the High Harmonic Fast Wave (HHFW) regime. Although modeling of HHFW heating and current drive has been performed at ORNL, UCSD, MIT, and PPPL, there are few experiments in this frequency range. In conventional tokamaks, the DIII-D experiments at the 5(th) - 7(th) cyclotron harmonic are the closest approach to the HHFW regime. In an ST, the only RF heating experiements to date have been performed at the 15(th) harmonic on the Current Drive eXperiment - Upgrade (CDX-U) at PPPL. General features of HHFW heating and current drive and the degree to which experimental confirmation of these features is available will be discussed. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Majeski, R (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Stutman, Dan/P-4048-2015 NR 9 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 296 EP 301 PG 6 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800047 ER PT S AU Carlsson, J Hellsten, T Hedin, J AF Carlsson, J Hellsten, T Hedin, J BE Bernabei, S Paoletti, F TI Toroidal effects on ICRF heating and current drive SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID CYCLOTRON CURRENT DRIVE; WAVES AB Numerical studies, performed with the Monte-Carlo code FIDO [1], of the evolution of the resonant-ion distribution function in the presence of ICRH. in toroidal geometry are presented. In particular it is pointed out how the absorption of toroidal momentum from a wave held with finite parallel wave numbers causes spatial drift and diffusion, which together with the finite orbit widths of the tail ions is shown to have a large effect on the temperature profile of the resonant ion species and also to cause losses of high-energy ions to the wall [2]. Furthermore, it is found that the finite orbit width and the inward drift occuring for negative parallel wave numbers [3] each give rise to a new mechanism of minority-ion cyclotron current drive as compared to earlier models where the drift orbits of the resonant ions are confined to the magnetic flux surfaces. For high levels of coupled power these new mechanisms are found to be the dominating ones [4,5]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Carlsson, J (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 333 EP 336 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800055 ER PT S AU Menard, JE Phillips, CK Mau, TK AF Menard, JE Phillips, CK Mau, TK BE Bernabei, S Paoletti, F TI Ion absorption effects in high-harmonic fast wave ray tracing theory SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID HIGH-BETA PLASMAS AB Effects of finite ion temperature on the propagation and absorption characteristics of high-harmonic fast waves (HHFW) are investigated theoretically using a hot electron (cord ion) ray tracing code in combination with solutions of the full hot plasma dispersion relation. Ray tracing is performed on numerical solutions of the Grad-Shafranov equation and the hot plasma dispersion relation is solved along the resultant ray trajectory using the cold ion n(parallel to). As was observed previously (see Ref. [1]), for typical expected plasma parameters in the National Spherical Torus Experiment (NSTX) [2], ion absorption begins to appear between 0.5 and 1.0keV local ion temperature at high deuterium cyclotron harmonics. Further, the ion power absorption rate is predicted to depend strongly on the launched parallel wavenumber [3,4]. Ray tracing on the full hot plasma dispersion relation has been attempted, but generally fails at high ion temperature near cyclotron harmonics primarily because the group velocity is ill-behaved. Such behavior usually suggests mode conversion to the ion-Bernstein wave (IBW). However, at sufficiently high n(parallel to) , mode conversion becomes negligible and the total power flux (Poynting+kinetic) is positive definite, while ray tracing still fails. The underlying cause of this apparent paradox is discussed. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Menard, JE (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 345 EP 348 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800058 ER PT S AU Majeski, R AF Majeski, R BE Bernabei, S Paoletti, F TI Direct electron heating at moderate harmonic number for compact ignition devices SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB Direct electron heating of compact ignition devices by radio-frequency power in the 300 - 400 MHz range is discussed. The possible advantage of this approach to heating an ignition device, as opposed to resonant heating of an ion population, is the insensitivity to the exact value of the magnitude field. Heating with central power deposition during a toroidal field ramp is therefore possible. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Majeski, R (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 353 EP 356 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800060 ER PT S AU Jaeger, EF Berry, LA Batchelor, DB AF Jaeger, EF Berry, LA Batchelor, DB BE Bernabei, S Paoletti, F TI Local one-dimensional ICRF full-wave solutions valid to all orders in k perpendicular to rho SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID PLASMAS AB High harmonic ion cyclotron resonances are important for understanding future fast wave heating experiments on NSTX1 as well as recent ICRF flow drive experiments on PBX-M-2 and TFTR3 Unfortunately, many of our ICRF wave analysis codes are based on an expansion to second order in k(perpendicular to) where k(perpendicular to) is the perpendicular wave number, and rho is the Larmor radius. Such codes are limited to cyclotron harmonics less than or equal to 2. Integral codes (4,5) on the other hand, are valid to all orders in both k(perpendicular to)rho and rho/L where L is the equilibrium scale length. But velocity space integrals in these codes require long running times. Here we take a simpler approach which assumes a local plasma conductivity (rho/L << 1), while still retaining all orders in k(perpendicular to)rho. This allows high harmonic fast wave and flow drive applications, while requiring less computing time than conventional integral codes. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Jaeger, EF (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 395 EP 398 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800069 ER PT S AU Ono, M AF Ono, M BE Bernabei, S Paoletti, F TI Cold electrostatic ion cyclotron waves for preionization and IBW launching in LHD SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB A folded waveguide with E-parallel to polarization is being installed on LHD device. The main purpose of the folded waveguide is to pre-ionize and create good target plasmas. The present manuscript proposes a launching of IBW via CESICW (Cold Electrostatic Ion Cyclotron Wave) for heating the core of LHD with the folded waveguide. The core heating can be accomplished by adding a minority hydrogen ion species in a helium majority plasma facilitating the mode-transformation of CESICW into IBW at the ion-ion hybrid resonance. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RP Ono, M (reprint author), Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. NR 5 TC 1 Z9 1 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 403 EP 406 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800071 ER PT S AU Carter, MD Bigelow, TS Batchelor, DB AF Carter, MD Bigelow, TS Batchelor, DB BE Bernabei, S Paoletti, F TI Accessibility of electron Bernstein modes in over-dense plasma SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys ID RESONANCE AB Mode-conversion between the ordinary, extraordinary and electron Bernstein modes near the plasma edge may allow signals generated by electrons in an over-dense plasma to be detected. Alternatively, high frequency power may gain accessibility to the core plasma through this mode conversion process. Many of the tools used for ion cyclotron antenna design can also be applied near the electron cyclotron frequency. In this paper, we investigate the the possibilities for an antenna that may couple to electron Bernstein modes inside an ova-dense plasma. The optimum values for wavelengths that undergo mode-conversion are found by scanning the poloidal and toroidal response of the plasma using a warm plasma slab approximation with a sheared magnetic field. Only a very narrow region of the edge can be examined in this manner; however, ray tracing may be used to follow the mode converted power in a more general geometry. It is eventually hoped that the methods can be extended to a hot plasma representation. Using antenna design codes, some basic antenna shapes will be considered to see what types of antennas might be used to detect or launch modes that penetrate the cutoff layer in the edge plasma. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Carter, MD (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 407 EP 410 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800072 ER PT S AU Baity, FW Barber, GC Carter, MD Goulding, RH Sparks, DO Chang-Diaz, FR McCaskill, GE Squire, JP AF Baity, FW Barber, GC Carter, MD Goulding, RH Sparks, DO Chang-Diaz, FR McCaskill, GE Squire, JP BE Bernabei, S Paoletti, F TI Design of RF systems for the RTD mission VASIMR SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB The first flight test of the variable specific impulse magnetoplasma rocket (VASIMR) is tentatively scheduled for the Radiation and Technology Demonstration (RTD) in 2003. This mission to map the radiation environment out to several earth radii will employ both a Hall thruster and a VASIMR during its six months duration, beginning from low earth orbit. The mission will be powered by a solar array providing 12 kW of direct current electricity at 50 V. The VASIMR utilizes radiofrequency (RF) power both to generate a high-density plasma in a helicon source and to accelerate the plasma ions to high velocity by ion cyclotron resonance heating (ICRH). The VASIMR concept is being developed by the National Aeronautics and Space Administration (NASA) in collaboration with national laboratories and universities. Prototype plasma sources, RF amplifiers, and antennas are being developed in the experimental facilities of the Advanced Space Propulsion Laboratory (ASPL). C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Baity, FW (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 417 EP 420 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800074 ER PT S AU Goulding, RH Bigelow, TS Swain, DW AF Goulding, RH Bigelow, TS Swain, DW BE Bernabei, S Paoletti, F TI Investigation of high voltage breakdown and arc localization in RF structures SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB An effort is underway to improve the voltage standoff capabilities of ion cyclotron range of frequencies (ICRF) heating and current drive systems. One approach is to develop techniques for determining the location of an electrical breakdown (arc) when it occurs. A technique is described which uses a measurement of the reflection coefficient of a swept frequency signal to determine the are location. The technique has several advantages including a requirement for only a small number of sensors and very simple data interpretation. In addition a test stand is described which will be used for studies of rf are behavior. The device uses a quarter-wave resonator to produce voltages to 90 kV in the frequency range of 55-80 MHz. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Goulding, RH (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. RI Goulding, Richard/C-5982-2016 OI Goulding, Richard/0000-0002-1776-7983 NR 4 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 425 EP 428 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800076 ER PT S AU Schilling, G Hosea, JC Wilson, JR Bonoli, PT Lee, WD Nelson-Melby, E Porkolab, M Wukitch, SJ AF Schilling, G Hosea, JC Wilson, JR Bonoli, PT Lee, WD Nelson-Melby, E Porkolab, M Wukitch, SJ BE Bernabei, S Paoletti, F TI Extension of Alcator C-Mod's ICRF experimental capability SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB A new 4-strap single-ended ICRF antenna has been added to the Alcator C-Mod tokamak. PPPL designed, fabricated, and tested the antenna up to 45 kV on an rf test stand. It is capable of symmetric phasing for ICRF heating studies, and asymmetric phasing with an improved directed wave spectrum for current drive. Two new 2 MW transmitters, tunable from 40-80 MHz, allow operation in plasma at 43, 60, and 78 MHz to match a variety of toroidal fields and plasma conditions. This addition increases the total available ICRF power to 4 MW at 80 MHz plus 4 MW at 40-80 MHz. Plasma heating and current drive experiments at the extended power levels and new frequencies are planned, and initial system performance will be discussed. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Schilling, G (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 429 EP 432 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800077 ER PT S AU Bigelow, TS Baity, FW Barber, GC Carter, MD Fadnek, A Ryan, PM Sparks, DO AF Bigelow, TS Baity, FW Barber, GC Carter, MD Fadnek, A Ryan, PM Sparks, DO BE Bernabei, S Paoletti, F TI Recent results from a folded waveguide ICRF antenna development project SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB Preliminary high power tests have been performed on a folded waveguide (FWG) ICRF launcher with a curved coupling faceplate installed. Two alternative faceplate configurations have been built and tested at low power and will be tested at high power in the near future. The new designs include a dipole plate which provides a 0-pi launch spectrum and a more transparent, flexible monopole face plate configuration. This FWG design is a 12 vane, 57 MHz design with a 0.31 m square cross section. The FWG can be installed with either fast wave or ion-Bernstein wave polarization and can also be retracted behind a Vacuum isolation valve. A 1 x 4 FWG array optimized for fast wave current drive on DIII-D has been conceptualized. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Bigelow, TS (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 437 EP 440 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800079 ER PT S AU Ryan, PM Swain, DW Wilgen, JB Fadnek, A Sparks, DO AF Ryan, PM Swain, DW Wilgen, JB Fadnek, A Sparks, DO BE Bernabei, S Paoletti, F TI Electrical testing of the full-scale model of the NSTX HHFW antenna array SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB The 30 MHz high harmonic fast wave (HHFW) antenna array for NSTX consists of 12 current straps, evenly spaced in the toroidal direction. Each pair of straps is connected as a half-wave resonant loop and will be driven by one transmitter, allowing rapid phase shift between transmitters. A decoupling network using shunt stub tuners has been designed to compensate for the mutual inductive coupling between adjacent current straps, effectively isolating the six transmitters from one another. One half of the array, consisting of six full-scale current strap modules, three shunt stub decouplers, and powered by three phase-adjustable rf amplifiers had been built for electrical testing at ORNL. Low power testing includes electrical characterization of the straps, operation and performance of the decoupler system, and mapping of the rf fields in three dimensions. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ryan, PM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 453 EP 456 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800083 ER PT S AU Swain, DW Carter, MD AF Swain, DW Carter, MD BE Bernabei, S Paoletti, F TI RF systems for a proposed next step option (FIRE) SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB FIRE (Fusion Ignition Research Experiment) is a high-field, burning-plasma tokamak that is being studied as a possible option for future fusion research Preliminary parameters for this machine are R-o approximate to 2 m, a approximate to 0.5 m, B-o approximate to 10 T, and I-p approximate to 6 MA. Magnetic field coils are to be made of copper and pre-cooled with LN,before each shot. The flat-top pulse length desired is greater than or equal to 10s. Ion cyclotron and lower hybrid rf systems will be used for heating and current drive. Present specifications call for 30 MW of ion cyclotron heating power, with 25 MW of lower hybrid power as an upgrade option. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Swain, DW (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 466 EP 469 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800086 ER PT S AU Efthimion, PC Hosea, JC Kaita, R Majeski, R Taylor, G AF Efthimion, PC Hosea, JC Kaita, R Majeski, R Taylor, G BE Bernabei, S Paoletti, F TI New electron cyclotron emission diagnostic based upon the electron Bernstein wave SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB Most magnetically confined plasma devices cannot take advantage of standard Electron Cyclotron Emission (ECE) diagnostics to measure temperature. They either operate at high density relative to their magnetic field or they do not have sufficient density and temperature to reach the blackbody condition. The standard ECE technique measures the electromagnetic waves emanating from the plasma. Here we propose to measure electron Bernstein waves (EBW) to ascertain the local electron temperature in these plasmas. The optical thickness of EBW is extremely high because it is an electrostatic wave with a large ki. One can reach the blackbody condition with a plasma density approximate to 10(11) cm(-3) and T-e approximate to 1 eV. This makes it attractive to most plasma devices. One serious issue with using EBW is the wave accessibility. EBW may be accessible by either direct coupling or mode conversion through an extremely narrow layer (approximate to 1-2 mm) in low field devices. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Efthimion, PC (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 486 EP 489 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800091 ER PT S AU Taylor, G LeBlanc, B Phillips, CK Schilling, G Wilson, JR Hubbard, A Bonoli, P Nelson-Melby, E Wukitch, SJ AF Taylor, G LeBlanc, B Phillips, CK Schilling, G Wilson, JR Hubbard, A Bonoli, P Nelson-Melby, E Wukitch, SJ BE Bernabei, S Paoletti, F TI Electron power deposition measurements during ion cyclotron range of frequency heating on C-Mod SO RADIO FREQUENCY POWER IN PLASMAS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 13th Topical Conference on Radio Frequency Power in Plasmas CY APR 12-14, 1999 CL ANNAPOLIS, MD SP Princeton Univ, Princeton Plama Phys Lab, Amer Inst Phys AB A 19-channel electron cyclotron emission (ECE) grating polychromator has been added to the existing ECE diagnostics on C-Mod, which include a 9-channel polychromator, heterodyne radiometer and Michelson interferometer. The new instrument can significantly improve the radial resolution of electron power deposition measurements in ICRF experiments on C-Mod. The improved resolution is important for resolving electron power deposition in off-axis mode conversion heating regimes where the mode conversion region can be narrow. The first data from this new instrument were acquired last year during 80 MHz hydrogen minority D-H mode conversion experiments where the H/(H+D) ratio was varied from 0.02 to 0.30 and the toroidal field was varied from 5.1 to 5.7 T. Although complicated by the presence of large sawteeth, some electron power deposition results were obtained from a break-in-slope method. These results, together with results from data acquired during the current C-Mod experimental campaign, will be presented and compared to predicted radial deposition profiles from the TORIC, 2-D full wave RF code, and the METS95, 1-D integral wave RF code. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Taylor, G (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-861-4 J9 AIP CONF PROC PY 1999 VL 485 BP 490 EP 493 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BN89C UT WOS:000083360800092 ER PT J AU Fitzgerald, TJ Argo, PE Carlos, RC AF Fitzgerald, TJ Argo, PE Carlos, RC TI Equatorial spread F effects on an HF path: Doppler spread, spatial coherence, and frequency coherence SO RADIO SCIENCE LA English DT Article ID PROPAGATION; IONOSPHERE; RADAR; KWAJALEIN; CHANNEL; VHF AB In August 1990 we participated in the Equatorial Ionospheric Studies sounding rocket campaign near Kwajalein Atoll in the equatorial Pacific region. The campaign included measurements of plasma density using rocket probes and coherent and incoherent scatter radar. During the campaign we fielded high-frequency ionospheric sounders over a bistatic path between Maloelap Atoll and Bikini Atoll in the Marshall Islands. The distance between the transmitters and receivers was 700 km; the ionospheric-reflection region was at 10.18 degrees N, 168.40 degrees E, near the magnetic equator. We made three types of measurements: Doppler spread and spatial coherence for a single-frequency CW path; frequency coherence of multiple CW paths; and Doppler spread and time-delay spread for a 60-kHz bandwidth path. We obtained such data over a period of 2 weeks for approximately 2 hours each evening; during this period spread F was common. Fifty percent of the evenings showed Doppler spread of greater than 6 Hz at the -10 dB level (relative to the peak signal power) and greater than 15 Hz at the -30 dB level. Forty percent of the evenings showed spatial coherence distance of less than 180 m in the direction normal to the bistatic path; 40% of the evenings showed spatial coherence of less than 75 m in the direction parallel to the path. Seventy-five percent of the evenings showed coherence bandwidths of less than 1.5 kHz. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Fitzgerald, TJ (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 21 TC 1 Z9 2 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JAN-FEB PY 1999 VL 34 IS 1 BP 167 EP 178 DI 10.1029/1998RS900013 PG 12 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 161QG UT WOS:000078299800014 ER PT J AU Mensing, SA Southon, JR AF Mensing, SA Southon, JR TI A simple method to separate pollen for AMS radiocarbon dating and its application to lacustrine and marine sediments SO RADIOCARBON LA English DT Article ID ACCELERATOR MASS-SPECTROMETRY; SANTA-BARBARA-BASIN; LAKE; MAZAMA; PEAT AB We present a simple method for manually separating pollen concentrates for radiocarbon accelerator mass spectrometry (AMS) dating using a mouth pipetting system. The required equipment is readily available from scientific equipment supply houses at minimal cost. Pollen samples from lake sediments required about 4 h of hand picking, whereas samples from marine sediments required about 8 h labor. Pollen dates from marine sediments were much older than expected. We are attempting to resolve whether this is due to contamination of the pollen or the presence of significant quantities of old reworked pollen. Pollen dates from lake sediments associated with Mazama Ash were consistent with other published ages; however, replicate dates on pollen samples from above the ash were consistently older than the surrounding sediment. Our results suggest that caution must be used when interpreting pollen dates if the potential for sediment reworking is present. C1 Univ Nevada, Dept Geog, Reno, NV 89507 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Mensing, SA (reprint author), Univ Nevada, Dept Geog, Reno, NV 89507 USA. NR 30 TC 22 Z9 24 U1 2 U2 7 PU UNIV ARIZONA DEPT GEOSCIENCES PI TUCSON PA RADIOCARBON 4717 E FORT LOWELL RD, TUCSON, AZ 85712 USA SN 0033-8222 J9 RADIOCARBON JI Radiocarbon PY 1999 VL 41 IS 1 BP 1 EP 8 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 191YD UT WOS:000080049000001 ER PT J AU Xu, HF Wang, YF AF Xu, HF Wang, YF TI Use of linear free energy relationship to predict Gibbs free energies of formation of MUO4 phases SO RADIOCHIMICA ACTA LA English DT Article DE uranium oxides; tungsten oxides; molybdenum oxides; Gibbs free energy of formation ID SOLIDS AB In this paper, the Sverjensky-Molling equation derived from a linear free energy relationship is used to calculate the Gibbs free energies of formation of MUO4, MWO4, and MMoO4 phases from the known thermodynamic properties of the corresponding aqueous divalent cations (M2+). The Svejensky-Molling equation is expressed as Delta G(f, MvX)(0) = a(MvX) Delta G(n, M)(0)(2+) + b(MvX) + beta(MvX) r(M)(2+), where the coefficients a(MvX), b(MvX), and beta(MvX) characterize a particular structural family of MvX, r(M)(2+) is the ionic radius of M2+ cation, Delta G(f, MvX)(0) is the standard Gibbs free energy of formation of MvX, and Delta G(n, M)(0)(2+) is the standard non-solvation energy of cation M2+. The coefficients for the family of alpha-M2+UO4 phases are: a(MvX) = 1.0552, b(MvX) = -510.40(kcal/mole), and beta(MvX) = 73.0 (kcal/mole . Angstrom). This relationship can be used to predict the Gibbs free energies of formation of various phases of MUO4, MWO4, MMoO4. C1 Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. Sandia Natl Labs, Carlsbad, NM 88220 USA. RP Xu, HF (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. NR 19 TC 4 Z9 4 U1 3 U2 4 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 87 IS 1-2 BP 37 EP 40 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 284KJ UT WOS:000085331300006 ER PT J AU Xia, YX Rao, LF Rai, D Felmy, AR AF Xia, YX Rao, LF Rai, D Felmy, AR TI Solvent extraction study of Np(IV) sulfate complexation in Na+-Np4+-OH--SO42--HSO4--ClO4- and Na+-Np4+-OH--SO42--HSO4--Cl- systems SO RADIOCHIMICA ACTA LA English DT Article DE neptunium (IV); sulfate; complex stability constants; solvent extraction; ion-interaction ID CONCENTRATED NACL; IONIC-STRENGTH; SOLUBILITY; THERMODYNAMICS AB Solvent extraction was used to study the complexation of Np(TV) with sulfate in NaClO4 and NaCl solutions ranging in concentration from 0.1 M to 5.0 M. A reducing agent (NH2OH.HCl) was used during extractions to maintain the tetravalent state of neptunium. Independent tests confirmed that the oxidation state of neptunium did not change during extractions. The distribution ratio of Np(IV) between the organic and aqueous phases was found to decrease as the concentration of sodium sulfate increased. Fitter's specific ion-interaction approach was used to model the solvent extraction results and calculate the thermodynamic stability constants of Np(IV)-sulfate complexes. At the sulfate concentrations used in these experiments, NpSO42+ and Np(SO4)(2)(0) were found to be the dominant aqueous species. Based on the data obtained over a wide range of concentrations of NaCl4 and NaCl the thermodynamic equilibrium constants were found to be 1.05 X 10(9) for the formation of NpSO42+ (Np4+ + SO42- reversible arrow NpSO42+) and 5.62X10(11) for the formation of Np(SO4)(2)(Np4+ + 2SO(4)(2-) reversible arrow Np(SO4)(2)). C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Rai, D (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 30 TC 10 Z9 10 U1 0 U2 1 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 86 IS 1-2 BP 33 EP 40 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 264RA UT WOS:000084194200005 ER PT J AU Rai, D Hess, NJ Felmy, AR Moore, DA Yui, M Vitorge, P AF Rai, D Hess, NJ Felmy, AR Moore, DA Yui, M Vitorge, P TI A thermodynamic model for the solubility of PuO2(am) in the aqueous K+-HCO3--CO32--OH--H2O system SO RADIOCHIMICA ACTA LA English DT Article DE PuO2(am); solubility; thermodynamics; Pu(IV) hydrous oxide; Pu(CO3)(5)(6-); carbonate complexes ID MULTIPLE-SCATTERING CALCULATIONS; HYDROUS OXIDE; HYDROLYSIS CONSTANTS; NATURAL-WATERS; CARBONATE; EQUILIBRIA; PU(IV); ION; COMPLEXATION; PREDICTION AB The solubility of PuO2(am) was determined in the aqueous K+-HCO3--CO32--OH--H2O system extending to high concentrations of carbonate and bicarbonate. X-ray absorption spectroscopy (XAS) and solvent extraction were used to identify species and oxidation states in the aqueous phase. The dominant aqueous species in relatively concentrated CO32- and HCO3- solutions were determined by XAS to be Pu(CO3)(5)(6-). The solubility of PuO2(am) increased dramatically with increasing total carbonate concentrations, indicating that carbonate makes strong complexes with Pu(IV). The dominant Pu(IV)-carbonate species that reasonably described all of the experimental data were Pu(CO3)(5)(6-) in high concentrations of carbonate and bicarbonate and Pu(OH)(2)(CO3)(2)(2-) in low concentrations of bicarbonate. Data suggest the possible presence of another species in the low carbonate and high pH region. However, because of uncertainty in Pu(IV) concentrations in this region, no attempt was made to fit the data in this region. The logarithm of the thermodynamic equilibrium constants for the PuO2(am) dissolution reactions involving Pu(CO3)(5)(6)- and Pu(OH)(2)(CO3)(2)(2-) [(PuO2(am) + 5 CO32- + 4 H+ reversible arrow Pu(CO3)(5)(6-) + 2 H2O) and (PuO2(am) + 2 HCO3- reversible arrow Pu(OH)(2)(CO3)(2)(2-))] were found to be 33.32 and -4.78, respectively. These values, when combined with the solubility product of PuO2(am) (log K-sp = -56.85 [1]), provided logarithm of the equilibrium constants of 34.18 and 44.76, respectively, for (Pu4+ + 5 CO32- reversible arrow Pu(CO3)(5)(6-)) and (Pu4+ + 2 CO32- + 2 OH- reversible arrow Pu(OH)(2)(CO3)(2)(2-). C1 Pacific NW Lab, Richland, WA 99352 USA. Japan Nucl Cycle Dev Inst, Tokai Works, Tokai, Ibaraki, Japan. CEA Saclay, DCC DESD SESD, F-91191 Gif Sur Yvette, France. RP Rai, D (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. OI Hess, Nancy/0000-0002-8930-9500 NR 36 TC 44 Z9 46 U1 1 U2 7 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 86 IS 3-4 BP 89 EP 99 PG 11 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 267PM UT WOS:000084368500002 ER PT J AU Rutsch, M Geipel, G Brendler, V Bernhard, G Nitsche, H AF Rutsch, M Geipel, G Brendler, V Bernhard, G Nitsche, H TI Interaction of uranium(VI) with arsenate(V) in aqueous solution studied by time-resolved laser-induced fluorescence spectroscopy (TRLFS) SO RADIOCHIMICA ACTA LA English DT Article DE uranium(VI); arsenate(V); fluorescence spectroscopy; complex formation; time-resolved laser-induced spectroscopy ID COMPLEXATION AB The uranyl arsenate system was studied by laser-induced time-resolved fluorescence spectroscopy in the pH range from 1.5 to 3.5 in 0.1 M NaClO4 solution. Three uranyl arsenate complexes were found: i) UO2(HAsO4)(aq), ii) UO2H2AsO4+, iii) UO2(H2AsO4)(2)(aq). They were characterized by their fluorescence spectra and fluorescence lifetimes. The following lifetimes were determined: i) 0.1 < tau < 1 mu s, ii) 12.2 +/- 1.2 mu s, iii) 38.3 +/- 3.5 mu s. The complex formation constants of the three uranyl arsenate complexes were calculated as log beta(0)(i) = 18.76 +/- 0.31, log beta(0)(ii) = 21.96 +/- 0.24 and log beta(0)(iii) = 41.53 +/- 0.20. The stoichiometrical ratio between uranium(VI) and arsenate(V) was confirmed by slope analysis. An uranium(VI) speciation to pH 5 was calculated using the determined complex formation constants. C1 Rossendorf Inc, Forschungszentrum Rossendorf EV, Inst Radiochem, D-01314 Dresden, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. RP Rutsch, M (reprint author), Rossendorf Inc, Forschungszentrum Rossendorf EV, Inst Radiochem, POB 510119, D-01314 Dresden, Germany. NR 16 TC 27 Z9 28 U1 0 U2 3 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 86 IS 3-4 BP 135 EP 141 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 267PM UT WOS:000084368500008 ER PT J AU Collon, P Cole, D Davids, B Fauerbach, M Harkewicz, R Kutschera, W Morrissey, DJ Pardo, RC Paul, M Sherrill, BM Steiner, M AF Collon, P Cole, D Davids, B Fauerbach, M Harkewicz, R Kutschera, W Morrissey, DJ Pardo, RC Paul, M Sherrill, BM Steiner, M TI Measurement of the long-lived radionuclide Kr-81 in pre-nuclear and present-day atmospheric krypton SO RADIOCHIMICA ACTA LA English DT Article DE Kr-81; accelerator mass spectrometry; groundwater dating; cosmogenic radionuclide ID ATOMS; SPECTROSCOPY AB Isotopic ratios of Kr-81/Kr in the range of 10(-13) were measured with accelerator mass spectrometry in pre-nuclear atmospheric krypton and in modem krypton. Within the experimental uncertainty (+/-30%) the Kr-81/Kr ratios were found to be the same. This establishes Kr-81 (t(1/2) = 230000 years) as a long-lived cosmogenic radionuclide essentially unaffected by anthropogenic contributions, and therefore well suited for dating applications. The anthropogenic "cleanliness" of Kr-81 is in accord with estimates for contributions from various human activities. C1 Univ Vienna, Inst Radiumforsch & Kernphys, Vienna Environm Res Accelerator, A-1090 Vienna, Austria. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP Kutschera, W (reprint author), Univ Vienna, Inst Radiumforsch & Kernphys, Vienna Environm Res Accelerator, Wahringerstr 17, A-1090 Vienna, Austria. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011 NR 20 TC 9 Z9 9 U1 0 U2 2 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 85 IS 1-2 BP 13 EP 19 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 229TP UT WOS:000082211100003 ER PT J AU Wruck, DA Palmer, CEA Silva, RJ AF Wruck, DA Palmer, CEA Silva, RJ TI A study of americium(III) carbonate complexation at elevated temperatures by pulsed laser photoacoustic spectroscopy SO RADIOCHIMICA ACTA LA English DT Article DE actinides; americium; americium carbonate; formation constant; photoacoustic spectroscopy; stability constant AB Equilibrium quotients for the reaction Am3+ + CO32- = AmCO3+ are determined by photoacoustic spectroscopy of aqueous solutions with 10(-6) m Am concentration. The logarithms of the equilibrium quotients at 0.1 m ionic strength are: 6.53 +/- 0.18 at 25 degrees C, 6.68 +/- 0.20 at 50 degrees C, and 7.54 +/- 0.43 at 75 degrees C. The 25 degrees C result is consistent with the thermodynamic equilibrium constant based on measurements by other techniques (electromigration, solubility, solvent extraction and spectrophotometry). The estimated enthalpy of reaction is 11 kJ/mol. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wruck, DA (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-231, Livermore, CA 94550 USA. NR 20 TC 3 Z9 3 U1 2 U2 4 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 85 IS 1-2 BP 21 EP 24 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 229TP UT WOS:000082211100004 ER PT J AU Marley, NA Gaffney, JS Orlandini, KA Drayton, PJ Cunningham, MM AF Marley, NA Gaffney, JS Orlandini, KA Drayton, PJ Cunningham, MM TI An improved method for the separation of Bi-210 and Po-210 from Pb-210 by using solid-phase extraction disk membranes: Environmental applications SO RADIOCHIMICA ACTA LA English DT Article DE solid-phase extraction membranes; Bi-210; Po-210; Pb-210, anionic exchange membranes; atmospheric aerosols, environmental measurement of Pb-210 daughters ID SAMPLES; LEAD; RA-226; RATIOS; WATERS; BE-7; AIR AB An improved method is described for the rapid separation of Bi-210 and Po-210 from the parent radionuclide, Pb-210, in environmental samples. After the metals were leached from a variety of matrices, they were converted to their anionic chloride complexes by addition of 1 M HCl. These complexes can be separated by solid-phase extraction with disk extraction membranes impregnated with anionic chelating particles. This separation technique takes advantage of the differences in sorption behavior of the chloride complexes to strongly basic anion exchange groups. The extraction membranes can then be counted directly for Bi-210 and Po-210. If sufficient time is allowed for ingrowth of the daughter, the concentration of the parent Pb-210 in the original sample can be determined from the concentration of Bi-210. In addition, the ratios of Bi-210/Pb-210 and Po-210/Pb-210 can be obtained by immediate extraction of Bi-210 followed by ingrowth of Bi-210 for a second determination to establish Pb-210 concentration levels. This can be accomplished easily in order to estimate the residence times of atmospheric aerosols or aqueous colloidal materials. This new technique avoids the time consuming extraction, precipitation, and electroplating procedures used previously and eliminates the experimental errors associated with multiple sample manipulations. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. RP Gaffney, JS (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 31 TC 5 Z9 7 U1 2 U2 4 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 85 IS 1-2 BP 71 EP 78 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 229TP UT WOS:000082211100010 ER PT J AU Dietz, ML Bond, AH Clapper, M Finch, JW AF Dietz, ML Bond, AH Clapper, M Finch, JW TI Isomer effects in the extraction of metal ions from acidic nitrate media by dicyclohexano-18-crown-6 SO RADIOCHIMICA ACTA LA English DT Article DE strontium; potassium; extraction; dicyclohexano-18-crown-6; stereoisomer ID MACROCYCLE INTERACTION; COMPLEX-FORMATION; AQUEOUS-SOLUTION; CROWN-ETHERS; KINETIC DATA; DICYCLOHEXYL-18-CROWN-6; STRONTIUM; PICRATES; SOLVENT; ANIONS AB The extraction of strontium and potassium from nitric acid by the cis-syn-cis and cis-anti-cis isomers of dicyclohexano-18-crown-6 (DCH18C6) in l-octanol is examined. Both isomers are shown to extract significant amounts of undissociated nitric acid. This extraction, along with the formation of metal-nitrate and metal-crown ether complexes in the aqueous phase, is shown to be important in determining the efficiency of metal ion extraction by the two isomers. The DCH18C6 isomer yielding the more efficient extraction of potassium or strontium is shown to depend upon the crown ether concentration and the aqueous nitric acid concentration. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. JEOL USA Inc, Peabody, MA 01960 USA. RP Dietz, ML (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 52 TC 35 Z9 35 U1 0 U2 4 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 85 IS 3-4 BP 119 EP 129 PG 11 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 238RY UT WOS:000082726200007 ER PT J AU Anderson, CJ Choppin, GR Pruett, DJ Costa, D Smith, W AF Anderson, CJ Choppin, GR Pruett, DJ Costa, D Smith, W TI Electrochemistry and spectroscopy of UO22+ in acidic AlCl3-EMIC SO RADIOCHIMICA ACTA LA English DT Article DE uranium; redox; speciation; molten salt; electrochemistry ID TEMPERATURE MOLTEN-SALTS; ALUMINUM-CHLORIDE; IONIC LIQUID; COMPLEXES; OXIDE AB The redox behavior of uranyl (UO22+) has been examined in acidic AlCl3-1-ethyl-3-methyl-imidazolium chloride (> 50 mol% AlCl3), a room temperature ionic liquid. Uranyl(VI) was reduced in bulk solution by a chloraluminate species (AlCl4-, Al2Cl7, or Al3Cl10-) to produce U(V) chloride (UCl6-). The kinetics of the reduction was investigated spectroscopically by monitoring the growth of spectral bands of U(V) chloride in the visible and near-IR regions of the spectrum over a five day period. Cyclic voltammetry of uranyl(VI) in acidic AlCl3-EMIC at a scan rate of 100 mV/second indicated three reduction reactions occurred at the electrode surface corresponding to the U(VI)/U(V), U(V)/U(TV) and U(IV)/U(III) redox couples. At slower scan speeds (5 mV/second) only two reductive processes were observed which are assigned to the U(V)/U(IV) and U(IV)/U(III) redox reactions. Bulk coulometry of UO2Cl2 in acidic AlCl3-EMIC indicated an average 1.7 electron reduction producing a solution which was verified spectroscopically to be U(IV). A possible mechanism for the behavior of uranyl(VI) in acidic AlCl3-EMIC involves removal of the oxygens from UO22+ in reactions with the solvent prior to the reduction, followed by reduction with AlCl4-. Uranyl(VI) is not a stable species in acidic room temperature ionic liquids. C1 Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Los Alamos Natl Lab, NMT Div, Los Alamos, NM 87545 USA. RP Choppin, GR (reprint author), Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. NR 23 TC 33 Z9 41 U1 2 U2 13 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 84 IS 1 BP 31 EP 36 PG 6 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 195RA UT WOS:000080264100004 ER PT J AU Shin, YS Burleigh, MC Dai, S Barnes, CE Xue, ZL AF Shin, YS Burleigh, MC Dai, S Barnes, CE Xue, ZL TI Investigation of uranyl adsorption on mesoporous titanium-based sorbents SO RADIOCHIMICA ACTA LA English DT Article DE uranyl; mesoporous; titania; adsorption ID FUNCTIONALIZED MONOLAYERS; PHYSICAL-PROPERTIES; SILICA-GEL; ION; DESIGN AB Mesoporous titanosilicate sol-gel materials with different silicon to titanium ratios were prepared by hydrothermal synthesis through the micellar template approach. The prepared samples have been characterized via infrared spectroscopy, nitrogen sorption, powder X-ray diffraction, and acid-base titration. The uptake of uranyl ion (UO22+) by the samples was determined at pH = 5.10. The uranyl loading capacity of the pure mesoporous titania was determined to be the largest. This capacity is much higher than that of the corresponding microporous material. The increase of capacity is correlated to the large surface area induced by the surfactant template synthetic method for mesoporous materials, increased concentrations of TiO- surface functional ligands, and large pore openings of the mesoporous materials allowing for access to the inner pore surfaces. The adsorption kinetics of our mesoporous sorbents are much faster than those of the corresponding microporous materials. The adsorption equilibria can be reached in less than 15 min. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Dai, S (reprint author), Oak Ridge Natl Lab, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. RI Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 32 TC 21 Z9 21 U1 0 U2 2 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 84 IS 1 BP 37 EP 42 PG 6 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 195RA UT WOS:000080264100005 ER PT J AU Paulus, W Kratz, JV Strub, E Zauner, S Bruchle, W Pershina, V Schadel, M Schausten, B Adams, JL Gregorich, KE Hoffman, DC Lane, MR Lane, C Lee, DM McGrath, CA Shaughnessy, DK Strellis, DA Sylwester, ER AF Paulus, W Kratz, JV Strub, E Zauner, S Bruchle, W Pershina, V Schadel, M Schausten, B Adams, JL Gregorich, KE Hoffman, DC Lane, MR Lane, C Lee, DM McGrath, CA Shaughnessy, DK Strellis, DA Sylwester, ER TI Chemical properties of element 105 in aqueous solution: Extraction of the fluoride-, chloride-, and bromide complexes of the group-5 elements into an aliphatic amine SO RADIOCHIMICA ACTA LA English DT Article DE niobium; tantalum; protactinium; element 105; extraction chromatography; Aliquat 336(F-)/HF, and Aliquat 336(Cl-)/HCl, and Aliquat 336(Br-)/HBr ID HCL AB Previously, the halide complex formation of the group-5 elements had been studied in mixed HCl/HF solutions by their extraction into triisooctyl amine (TiOA). The extraction sequence Ta > Nb > 105 > Pa was observed, while theoretical calculations performed for the pure chloride system predict the reversed sequence of extraction. To verify this experimentally, new batch extraction experiments for Nb, Ta, and Pa from pure HCl-, HBr-, and HF solutions were performed with various aliphatic amines. Based on these results, new reversed-phase micro chromatographic column separations were elaborated using the quaternary ammonium salt Aliquat 336 on an inert support in the computer-controlled chromatography apparatus ARCA II. In the system Aliquat 336(F-)/HF, after feeding of the activity onto the column in 0.5 M HF, element 105 did not elute in 4 M HF (Pa fraction) but showed a higher distribution coefficient (>570), close to that of Nb land Ta). In the system Aliquat 336(Cl-)/ HCl, after feeding onto the column in 10 M HCl, element 105 showed a distribution coefficient in 6 M HCl (similar to 438) close to that of Nb establishing the extraction sequence Pa > Nb greater than or equal to 105 > Ta. Exactly this sequence has been predicted theoretically based on relativistic calculations of the electronic structure of hydrolzed species of Nb, Ta, Pa, and element 105, and of their various complexes formed in HCl solutions, i.e. by explicitly considering the competition between hydrolysis and complex formation. In this way, the extraction sequence fluorides much greater than chlorides > bromides for the group-5 halide complexes is also correctly predicted. C1 Univ Mainz, Inst Kernchem, D-55099 Mainz, Germany. Gesell Schwerionenforsch GmbH, D-64291 Darmstadt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Paulus, W (reprint author), Univ Mainz, Inst Kernchem, D-55099 Mainz, Germany. RI McGrath, Christopher/E-8995-2013; Strub, Erik/N-1308-2015 OI Strub, Erik/0000-0002-4136-2871 NR 24 TC 36 Z9 37 U1 2 U2 7 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 84 IS 2 BP 69 EP 77 PG 9 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 209XH UT WOS:000081074600002 ER PT J AU Gibson, JK AF Gibson, JK TI Gas-phase reactions of An(+) and AnO(n)(+) [An = Th, U, Np, Pu, Am] with halogenated hydrocarbons [C14F24, C3F6, C2H4Cl2 and C2H4Br2] SO RADIOCHIMICA ACTA LA English DT Article DE actinide halides; laser ablation; gas-phase reactions; organoactinides; actinide ions ID LASER-ABLATION SYNTHESIS; ORGANOMETALLIC CHEMISTRY; LANTHANIDE CATIONS; CYCLIC HYDROCARBONS; PHENYL HALIDES; ION CHEMISTRY; ALKYL-HALIDES; OXO-LIGAND; METAL; URANIUM AB Gas-phase reactions of laser-ablated actinide metal and oxide ions, An(+) and AnO(1.2)(+) (An = Th, U, Np, Pu, Am), with per fluorocarbons (C14F24 and C3F6), 1,2-dichloroethane (C2H4Cl2) and 1,2-dibromoethane (C2H4Br2) were studied by laser ablation with prompt reaction and detection. A primary goal was to determine variations in reaction pathways within the region of the actinide series where a progression from d-block transition metal-like (e.g.. Th') to lanthanide-like (e.g., Am+) chemistry is manifested. The high stabilities of the actinide fluorides, AnF(x)(+) and AnOF(x)(+), resulted in F-abstraction as the primary reaction channel with perfluorocarbons. The studied An exhibited discrepant proclivities towards F-abstraction which reflected variable oxidation state stabilities. Thus, Np produced (NpF3+)-F-IV and (NpOF2+)-O-V whereas oxidation of Am terminated at (AmF2+)-F-III. Reactions of An(+) with C2H4Cl2 produced exclusively AnCl(1,2)(+) whereas reactions with C2H4Br2 produced both AnBr(1,2)(+) and AnC(2l)H(2). The distinctive appearance of dehydrobromination as a reaction pathway is interpreted in the context of organoactinide reaction mechanistics. Halogen abstraction reactions are of interest for assessing chemical manifestations of the changing oxidation behavior across the actinide series and may be of utility for post-ionization separation of actinides for purification or analy sis. Also identified were directly ablated oxide cluster ions such as ThUO4+, NpPuO3+ and U2ThO7+ - their compositions and abundances are correlated with solid actinide oxide chemistry. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gibson, JK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 51 TC 8 Z9 8 U1 2 U2 9 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 84 IS 3 BP 135 EP 146 PG 12 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 214QE UT WOS:000081338000003 ER PT J AU Rai, D Hess, NJ Felmy, AR Moore, DA Yui, M AF Rai, D Hess, NJ Felmy, AR Moore, DA Yui, M TI A thermodynamic model for the solubility of NpO2(am) in the aqueous K+-HCO3--CO32--OH--H2O system SO RADIOCHIMICA ACTA LA English DT Article DE NpO2(am); solubility; thermodynamics; Np(IV) hydrous oxide; Np(CO3)(5)(6-); carbonate complexes ID MULTIPLE-SCATTERING CALCULATIONS; HYDROLYSIS CONSTANTS; NATURAL-WATERS; HYDROUS OXIDE; CARBONATE; NEPTUNIUM(IV); PREDICTION AB Solubility of NpO2(am) was determined in the aqueous K+HCO3-CO32 -OH -H2O system extending to high concentrations of carbonate, bicarbonate, and mixed carbonate-hydroxide. Several reducing agents (Fe powder, Na2S2O4, NH . NH2, and NH2OH . HCl) were tested for their effectiveness to maintain neptunium in the tetravalent state. Of these reducing agents, Na2S2O4 was found to be the most effective. Even in the presence of Na2S2O4. significant oxidation of Np(IV) to Np(V) occurred in samples containing relatively low concentrations of carbonate/bicarbonate, relatively high concentrations of hydroxide, and samples equilibrated for relatively long periods. X-ray absorption spectroscopy (XAS) and solvent extraction were used to identify aqueous species and oxidation states and to help select appropriate data sets for thermodynamic interpretations. The dominant aqueous species in CO: and relatively concentrated HCO, solutions was found by XAS to be Np(CO3)(5)(6-). Solubility of NpO2(am) in carbonate and bicarbonate solutions increased dramatically with increasing molal concentrations (carbonate >0.1 moles per kg H2O (m) and bicarbonate >0.01m), indicating that carbonate makes strong complexes with Np(IV). The dominant Np(IV)-carbonate species that reasonably described all of the experimental data were Np(CO,): in low to high concentrations of carbonate and hy droxide and in high concentrations of bicarbonate, and Np(OH)(2)(CO3)(2)(2-) in low concentrations of bicarbonate. The logarithm of the thermodynamic equilibrium constants for the NpO2(am) dissolution reactions involving these species [(NpO2(am) + 5 CO32- + 4 H+ reversible arrow Np(CO3)(5)(6-) + 2 H2O) and (NpO2(am) + 2 HCO3- reversible arrow Np(OH)(2)(CO3)(2)(2-))] were found to be 34.85 and -4.4, respectively. These values, when combined with the solubility product of NpO2(am) [log K-Sp = -54.9 [1, and recent unpublished data from Rai et al.]], provided logarithm of the equilibrium constants of 33.79 and 43.17, respec tively for (Np4+ + 5 CO32- reversible arrow Np(CO3)(5)(6-)) and (Np4+ + 2 CO32- 2 OH reversible arrow Np(OH)(2)(CO3)(2)(2-)). C1 Pacific NW Lab, Richland, WA 99352 USA. Tokai Works, Japan Nucl Cycle Dev Inst, Tokai, Ibaraki, Japan. RP Rai, D (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. OI Hess, Nancy/0000-0002-8930-9500 NR 28 TC 32 Z9 32 U1 0 U2 10 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 84 IS 3 BP 159 EP 169 PG 11 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 214QE UT WOS:000081338000006 ER PT J AU Panak, P Selenska-Pobell, S Kutschke, S Geipel, G Bernhard, G Nitsche, H AF Panak, P Selenska-Pobell, S Kutschke, S Geipel, G Bernhard, G Nitsche, H TI Complexation of U(VI) with cells of Thiobacillus ferrooxidans and Thiomonas cuprina of different geological origin SO RADIOCHIMICA ACTA LA English DT Article DE uranium; Thiobacillus ferrooxidans; bioaccumulation; time-resolved laser fluorescence spectroscopy ID SPANISH URANIUM ORE; FLUORESCENCE SPECTROSCOPY TRLFS; BIOTECHNOLOGY; SPECIATION; METALS; WASTES; PILE; NOV AB Recently, we demonstrated that the strain Thiobacillus ferrooxidans ATCC 33020 which is recovered from a uranium mine is taxonomically neither closely related to the type strain of the species Thiobacillus ferrooxidans nor to several other strains of this species stemming from copper and coal mines. In the present work, the interaction was studied of the above-mentioned strains with U(VI). We found that the uranium mine isolate 33020 accumulates significantly higher amounts of U(VI) in comparison to the other T. ferrooxidans strains studied. Extraction studies with sulfuric acid released none, and with EDTA only a small fraction (10-42%) of the U(VI) that was accumulated by the bacteria. The main part of the uranium was irreversibly bound to the biomass. Time-resolved laser fluorescence spectroscopy demonstrated the formation of strong inner-sphere complexes of U(VI) with the bacteria, Moreover, the binding strength of the Thiobacillus ferrooxidans complexes corresponds to the accumulation capability of the strains, i.e., the strongest was the complex with the uranium mine isolate 33020. In addition, the interaction was investigated with U(VI) of a bacterial strain recovered from a uranium mine, but belonging to another bacterial species, Thiomonas cuprina. This strain interacts in a different manner with uranium. Its capability to bind U(VI) was higher than those of all T. ferrooxidans strains, but the complexes formed were less stable. C1 Forschungszentrum Rossendorf EV, Inst Radiochem, D-01314 Dresden, Germany. RP Panak, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 39 TC 18 Z9 18 U1 0 U2 3 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 1999 VL 84 IS 4 BP 183 EP 190 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 222UX UT WOS:000081804600002 ER PT J AU Schultz, JC Hack, CA Benner, WH AF Schultz, JC Hack, CA Benner, WH TI Polymerase chain reaction products analyzed by charge detection mass spectrometry SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID INDUCED CONFORMATIONAL-CHANGES; ELECTROSPRAY IONS; BLOOD DNA; DIAGNOSIS; PCR AB Charge detection mass spectrometry (CDMS) has been used to rapidly analyze polymerase chain reaction (PCR) products with a minimum of sample cleanup after the PCR reaction. PCR products of 1525 base pairs (bp), 1982 bp and 2677 bp were detected by CDMS, where simultaneous measurement of the charge and velocity of an electrostatically accelerated ion allows a mass determination of the ion. We extended the investigation to a longer double-stranded, linear DNA sample by also analyzing linearized pBR322 (4361 bp), Positive ion mass spectra and ion charge-state distributions were obtained for these electrosprayed DNA samples. Instrumental conditions were studied using a commercially available, linearized pUC18 sample (2682 bp). Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. RP Schultz, JC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 23 TC 25 Z9 25 U1 0 U2 7 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 1 BP 15 EP 20 DI 10.1002/(SICI)1097-0231(19990115)13:1<15::AID-RCM439>3.3.CO;2-1 PG 6 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 156EF UT WOS:000077987900003 ER PT J AU Kornienko, O Reilly, PTA Whitten, WB Ramsey, JM AF Kornienko, O Reilly, PTA Whitten, WB Ramsey, JM TI Micro ion trap mass spectrometry SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID ELECTROSPRAY AB Experiments to perform mass spectrometry with ion traps of submillimeter dimension are described. Several trap geometries amenable to microfabrication have been explored. In these experiments, vapor-phase molecules were ionized by a pulse from a frequency-quadrupled Nd:YAG laser. The ions were trapped and mass analyzed by manipulating the radiofrequency voltages on the trap electrodes. Effects of trapping parameters on mass resolution and sensitivity are discussed. (C) 1999 John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Whitten, WB (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6142, Oak Ridge, TN 37831 USA. NR 17 TC 76 Z9 78 U1 0 U2 16 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 1 BP 50 EP 53 DI 10.1002/(SICI)1097-0231(19990115)13:1<50::AID-RCM449>3.3.CO;2-B PG 4 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 156EF UT WOS:000077987900008 ER PT J AU Barlow, SE Tinkle, MD AF Barlow, SE Tinkle, MD TI Radiative association of Cs+ with 12-crown-4 ether at 288 K SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID CH-3+; H-2 AB We report the measurement of radiative association rates of Cs+ with 12-crown-4 ether. The measurement improves on the precision of earlier measurements by about a factor of ten and demonstrates some of the power of an ion cyclotron resonance mass spectrometer recently designed and built by the authors. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Pacific NW Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Barlow, SE (reprint author), Pacific NW Lab, WR Wiley Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 12 TC 4 Z9 4 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 5 BP 390 EP 392 DI 10.1002/(SICI)1097-0231(19990315)13:5<390::AID-RCM497>3.0.CO;2-6 PG 3 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 177CE UT WOS:000079189200016 ER PT J AU Lammert, SA AF Lammert, SA TI 1999 directory of mass spectrometry manufactures and suppliers SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID PRODUCTS; SYSTEMS AB An annual directory of companies that supply mass spectrometers and mass spectrometry components and services. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lammert, SA (reprint author), Oak Ridge Natl Lab, M-S 6120,POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 10 BP 831 EP 844 PG 14 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 198GT UT WOS:000080415700001 ER PT J AU Saenz, AJ Petersen, CE Valentine, NB Gantt, SL Jarman, KH Kingsley, MT Wahl, KL AF Saenz, AJ Petersen, CE Valentine, NB Gantt, SL Jarman, KH Kingsley, MT Wahl, KL TI Reproducibility of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for replicate bacterial culture analysis SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID FAST ATOM BOMBARDMENT; RAPID IDENTIFICATION; PHOSPHOLIPIDS; COLI AB Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was used to demonstrate the reproducibility of bacterial spectra collected on different days. The reproducibility of analysis by MALDI-MS of intact Escherichia coli and Bacillus atrophaeus is presented as a replicate culture study in which spectra were collected on ten different occasions over a three-month period and by two different operators. The analysis resulted in the detection of specific biomarkers in the m/z 2000-20000 range. Some of the peaks in the Escherichia call spectra are identified by comparison with other published work. All of the spectra obtained are reproducible over the course of the experiment, but operator variability does exist. The Escherichia coli spectra show operator variability while the Bacillus atrophaeus spectra do not. This work demonstrates the utility of MALDI in obtaining consistent spectra from bacteria over a period of time. Copyright (C) 1999 John Whey & Sons, Ltd. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Wahl, KL (reprint author), Pacific NW Lab, POB 999,MS P8-08, Richland, WA 99352 USA. NR 20 TC 95 Z9 97 U1 1 U2 6 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 15 BP 1580 EP 1585 DI 10.1002/(SICI)1097-0231(19990815)13:15<1580::AID-RCM679>3.0.CO;2-V PG 6 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 222NE UT WOS:000081791000004 PM 10421900 ER PT J AU Jarman, KH Daly, DS Petersen, CE Saenz, AJ Valentine, NB Wahl, KL AF Jarman, KH Daly, DS Petersen, CE Saenz, AJ Valentine, NB Wahl, KL TI Extracting and visualizing matrix-assisted laser desorption/ionization time-of-flight mass spectral fingerprints SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID FAST ATOM BOMBARDMENT; BACTERIAL PHOSPHOLIPIDS; SPECTROMETRY AB We have developed a method for constructing and extracting matrix-assisted laser desorption/ionization (MALDI) fingerprints, This method is fully automated and statistically based, allowing a large number of spectra to be analyzed at a time in an objective manner. This method can be used to extract the fingerprint of a particular analyte from a spectrum containing multiple analytes, Therefore, this method lends itself well to real-world applications where samples to be analyzed are likely to be impure, We illustrate this method on experimental results from a series of studies of E. coli and B. atrophaeus MALDI time-of-flight mass spectrometry (TOFMS) fingerprints. Copyright (C) 1999 John Whey & Sons, Ltd. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Wahl, KL (reprint author), Pacific NW Lab, POB 999,MS P8-08, Richland, WA 99352 USA. NR 14 TC 63 Z9 68 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 15 BP 1586 EP 1594 DI 10.1002/(SICI)1097-0231(19990815)13:15<1586::AID-RCM680>3.0.CO;2-2 PG 9 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 222NE UT WOS:000081791000005 PM 10421901 ER PT J AU Stephenson, JL Cargile, BJ McLuckey, SA AF Stephenson, JL Cargile, BJ McLuckey, SA TI Ion trap collisional activation of disulfide linkage intact and reduced multiply protonated polypeptides SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID TANDEM MASS-SPECTROMETRY; ASSISTED LASER-DESORPTION; RESOLVED ISOTOPIC PEAKS; ELECTROSPRAY IONIZATION; CHARGED IONS; LARGE MOLECULES; GAS-PHASE; CAPILLARY ELECTROPHORESIS; PROTEIN IDENTIFICATION; SEQUENCE INFORMATION AB The presence of disulfide linkages in multiply charged polypeptide ions tends to inhibit the formation of structurally informative product ions under conventional quadrupole ion trap collisional activation conditions, In particular, fragmentation that requires two cleavages (i.e., cleavage of a disulfide linkage and a peptide linkage) is strongly suppressed, Reduction of the disulfide linkage(s) by use of dithiothreitol yields parent ions upon electrospray without this complication. Far richer structural information is revealed by ion trap collisional activation of the disulfide-reduced species than from the native species. These observations are illustrated with doubly protonated native and reduced somatosin, the [M + 5H](5+) ion of native bovine insulin and the [M + 4H](4+) and [M + 3H](3+) ions of the B-chain of bovine insulin produced by reduction of the disulfide linkages in insulin, and the [M + 11H](11+) ion of native chicken lysozyme and the [M + 11H](11+) and [M + 14H](14+) ions of reduced lysozyme, In each case, the product ions produced by ion trap collisional activation were subjected to ion/ion proton transfer reactions to facilitate interpretation of the product ion spectra, These studies clearly suggest that the identification of polypeptides with one or more disulfide linkages via application of ion trap collisional activation to the multiply charged parent ions formed directly by electrospray could be problematic, Means for cleaving the Bisulfide linkage, such as reduction by dithiothreitol prior to electrospray, are therefore desirable in these cases, Copyright (C) 1999 John Whey & Sons, Ltd. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Stephenson, JL (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Stephenson, James/A-9262-2009; McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 69 TC 63 Z9 64 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 1999 VL 13 IS 20 BP 2040 EP 2048 DI 10.1002/(SICI)1097-0231(19991030)13:20<2040::AID-RCM754>3.3.CO;2-N PG 9 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 244ZM UT WOS:000083080700012 PM 10510418 ER PT S AU Klintenberg, M Edvardsson, S Guillot-Noel, O Viana, B Thomas, JO AF Klintenberg, M Edvardsson, S Guillot-Noel, O Viana, B Thomas, JO BE Woodward, RC TI The use of molecular dynamics to simulate the temperature dependence of the calculated absorption spectrum for Nd3+: YAG SO RARE EARTHS '98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Conference on Rare Earths CY OCT 25-30, 1998 CL FREMANTLE, AUSTRALIA SP Rhodia Rare Earths & Gallium, China Rare Earths Informat Ctr, Australian Nuclear Sci & Technol Org, Hewlett Packard, Mat Inst Western Australia, Special Res Ctr Adv Mineral & Mat Processing, Western Australian Dept Commerce & Trade, Western Australian Dept Resources Dev DE molecular dynamics; crystal field; temperature dependence; absorption spectra; Nd3+: YAG ID CRYSTAL-FIELD CALCULATIONS; RARE-EARTH COMPOUNDS; INTENSITY PARAMETERS; EU3+ ION; TRANSITIONS; ENERGY AB The use of molecular dynamics (MD) and the inclusion of configuration interaction (CI) effects have been shown to be important in the simulation of polarized absorption spectra for rare-earth doped compounds. This work, focuses on how well the MD approach can account for the temperature dependence of the calculated absorption spectrum for Nd3+:YAG, using the standard MD pair-potential of the Born-Mayer-Huggins form. All simulated spectra are compared to the corresponding experimental spectra. The results indicate that the simple pair-potential must be replaced by a many-body potential to describe the motion of the ions with sufficient accuracy. They also suggest that an "effective temperature" (T') should be used in the MD simulation of the form T'=aT+b. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Mid Sweden Univ, Inst Phys & Math, SW-85170 Sundsvall, Sweden. ENSCP, CNRS, URA 7574, Lab Chim Appliquee Etat Solide, FR-75231 Paris, France. Uppsala Univ, Angstrom Lab, SW-75121 Uppsala, Sweden. RP Klintenberg, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd 55-121, Berkeley, CA 94720 USA. NR 29 TC 0 Z9 0 U1 0 U2 1 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-841-9 J9 MATER SCI FORUM PY 1999 VL 315-3 BP 42 EP 50 PG 9 WC Chemistry, Multidisciplinary; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA BP25S UT WOS:000084507800005 ER PT S AU Gschneidner, KA Pecharsky, VK Pecharsky, AO Zimm, CB AF Gschneidner, KA Pecharsky, VK Pecharsky, AO Zimm, CB BE Woodward, RC TI Recent developments in magnetic refrigeration SO RARE EARTHS '98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Conference on Rare Earths CY OCT 25-30, 1998 CL FREMANTLE, AUSTRALIA SP Rhodia Rare Earths & Gallium, China Rare Earths Informat Ctr, Australian Nuclear Sci & Technol Org, Hewlett Packard, Mat Inst Western Australia, Special Res Ctr Adv Mineral & Mat Processing, Western Australian Dept Commerce & Trade, Western Australian Dept Resources Dev DE gadolinium; Gd-5(SixGe1-x)(4); heat capacity; magnetic refrigeration; magnetocaloric effect; refrigeration capacity ID GD-5(SI2GE2) AB The large magnetocaloric effect (MCE) of Gd metal has enabled us to successfully test a near-room temperature proof-of-principle apparatus and to show that magnetic refrigeration (MR) is a viable and competitive technology with gas compression/expansion refrigeration. A search for new materials with improved magnetocaloric properties has led to the discovery of the giant MCE in Gd-5(SixGe1-x)(4) alloys. These intermetallic compounds should make MR even more efficient and will open the doors to new possibilities for MR. The future prospects of magnetic refrigeration as an important rare earth market are discussed. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Astronaut Corp Amer, Madison, WI 53718 USA. RP Gschneidner, KA (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 10 TC 240 Z9 244 U1 6 U2 30 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-841-9 J9 MATER SCI FORUM PY 1999 VL 315-3 BP 69 EP 76 PG 8 WC Chemistry, Multidisciplinary; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA BP25S UT WOS:000084507800008 ER PT S AU Vogt, T Reilly, JJ Johnson, JR Adzic, GD McBreen, J AF Vogt, T Reilly, JJ Johnson, JR Adzic, GD McBreen, J BE Woodward, RC TI Non-stoichiometric AB(5) type alloys and their properties as metal hydride electrodes SO RARE EARTHS '98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Conference on Rare Earths CY OCT 25-30, 1998 CL FREMANTLE, AUSTRALIA SP Rhodia Rare Earths & Gallium, China Rare Earths Informat Ctr, Australian Nuclear Sci & Technol Org, Hewlett Packard, Mat Inst Western Australia, Special Res Ctr Adv Mineral & Mat Processing, Western Australian Dept Commerce & Trade, Western Australian Dept Resources Dev DE non-stoichiometry; AB(5) alloys; battery electrodes; corrosion; neutron diffraction ID ELECTROCHEMICAL CYCLING STABILITY; FORMING COMPOUNDS; X-RAY; COBALT AB Nickel-metal hydride batteries (NiMH) are replacing nickel-cadmium batteries (NiCd) due to their higher energy density and benign environmental impact. Furthermore, they are the first generation batteries for hybrid and electrical vehicles [1,2]. Current AB(5) electrodes necessarily contain expensive cobalt to obtain a reasonable cycle life. As a first step to eliminate Co as an alloy component the structure of LaNi3.55Co.75Mn.4Al.3 was determined. In order to definitively determine the site preference of cobalt a null scattering Ni alloy was prepared using appropriate Ni isotopes. In addition a new class of cobalt free non-stoichiometric La(NiSn)(5+x) alloys was identified which have cycle lives and storage capacities comparable to commercial alloys containing 10 wt% cobalt. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Vogt, T (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 21 TC 2 Z9 2 U1 0 U2 1 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-841-9 J9 MATER SCI FORUM PY 1999 VL 315-3 BP 94 EP 104 PG 11 WC Chemistry, Multidisciplinary; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA BP25S UT WOS:000084507800011 ER PT S AU Kwok, WK Paulius, L Lopez, D Safar, H Olsson, RJ Petrean, AM Crabtree, GW AF Kwok, WK Paulius, L Lopez, D Safar, H Olsson, RJ Petrean, AM Crabtree, GW BE Woodward, RC TI Induced point and correlated disorder pinning in untwinned YBa2Cu3O7-delta crystals SO RARE EARTHS '98 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT International Conference on Rare Earths CY OCT 25-30, 1998 CL FREMANTLE, AUSTRALIA SP Rhodia Rare Earths & Gallium, China Rare Earths Informat Ctr, Australian Nuclear Sci & Technol Org, Hewlett Packard, Mat Inst Western Australia, Special Res Ctr Adv Mineral & Mat Processing, Western Australian Dept Commerce & Trade, Western Australian Dept Resources Dev DE superconductivity; vortex pinning ID LATTICE-MELTING TRANSITION; VORTEX LIQUID; SUPERCONDUCTOR YBA2CU3O7-DELTA; ION IRRADIATION; STATE AB The magnetic phase diagram of untwinned single crystals of YBa2Cu3O7-delta is studied via transport measurements. We show that the first order vortex melting line which terminates at a critical point in high magnetic fields is strongly dependent on point disorder induced by proton irradiation, In addition, we report on the effect of heavy ion irradiation induced columnar defects on vortex pinning. We find a consistent change in the slope of the irreversibility line at the matching field and a remarkable reversal of the pinning anisotropy. Anisotropic pinning from columnar defects induced by uranium heavy ions can extend up to T-co, suggesting that even in the superconducting fluctuation regime, these defects are capable of pinning the vortex liquid. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Sci & Technol Ctr Superconduct, Argonne, IL 60439 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Univ Illinois, Dept Phys, Chicago, IL USA. Michigan State Univ, Dept Phys, E Lansing, MI 48824 USA. RP Kwok, WK (reprint author), Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-841-9 J9 MATER SCI FORUM PY 1999 VL 315-3 BP 314 EP 321 PG 8 WC Chemistry, Multidisciplinary; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA BP25S UT WOS:000084507800041 ER PT S AU Edvardsson, S Klintenberg, M AF Edvardsson, S Klintenberg, M BE Woodward, RC TI The use of Cl calculated polarizabilities to study rare-earth CFP dependencies in the laser host RE : YLF SO RARE EARTHS '98 SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Conference on Rare Earths CY OCT 25-30, 1998 CL FREMANTLE, AUSTRALIA SP Rhodia Rare Earths & Gallium, China Rare Earths Informat Ctr, Australian Nuclear Sci & Technol Org, Hewlett Packard, Mat Inst Western Australia, Special Res Ctr Adv Mineral & Mat Processing, Western Australian Dept Commerce & Trade, Western Australian Dept Resources Dev DE rare-earth; crystal field parameters; Sternheimer method; polarizabilities; shielding ID ENERGY-LEVELS; CRYSTAL-FIELD; LIYF4; IONS; CONSISTENCY; EQUATION; TM3+ AB It has earlier been shown that the Sternheimer method is appropriate in deriving crystal field parameters (CFP) for pr(3+) and Nd3+ doped in YLF [1] or Nd3+ in YAG [2]. In this connection, the dipole (alpha(D)) and quadrupole (alpha(Q)) polarizabilities for the whole rare-earth (RE) series will be presented. These are needed for the self consistent lattice summations performed. The various rare-earth wavefunctions needed for the computations are derived from the well known relativistic full Hartree-Fock code by R. D. Cowan. The main CFP behaviour for the various RE dopants in YLF are seen to agree fairly well with the experimentally fitted parameters. Covalency effects are, as expected, observed to be more important for higher order parameters. It is also seen that the contribution to the crystal field due to covalency is approximately constant for a given B-tp This observation is also supported by calculations of Newman [3]. The shielding, nuclear antishielding factors and radial integrals for the whole RE series are also presented. C1 Mid Sweden Univ, Dept Math & Phys, SW-85170 Sundsvall, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Mid Sweden Univ, Dept Math & Phys, SW-85170 Sundsvall, Sweden. NR 24 TC 13 Z9 13 U1 0 U2 2 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-841-9 J9 MATER SCI FORUM PY 1999 VL 315-3 BP 407 EP 414 PG 8 WC Chemistry, Multidisciplinary; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA BP25S UT WOS:000084507800054 ER PT S AU Gerstl, SAW AF Gerstl, SAW BE Cecchi, G Engman, ET Zilioli, E TI Building a global hotspot ecology with Triana data SO REMOTE SENSING FOR EARTH SCIENCE, OCEAN, AND SEA ICE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Remote Sensing for Earth Science, Ocean, and Sea Ice Applications CY SEP 20-24, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE ecology; land surface reflectance; Triana satellite; hotspot; BRDF; earth radiation budget AB Triana is an Earth remote sensing satellite to be located at the distant Langrange Point L-l, the gravity-neutral point between the Earth and the Sun. It will provide continuous full disk images of the entire sunlit side of the Earth with 8 km pixel resolution. The primary remote sensing instrument on Triana is a calibrated multispectral imager with 10 spectral channels in the UV, VIS, and NIR between 317 and 870 nm (reflected solar radiation). Due to its unique location at the Lagrange L-l point, in the direct line-of-sight between Earth and Sun Triana will view the Earth always in and near the solar retro-reflection direction which is also known as the hotspot direction. The canopy hotspot effect has rich information content for vegetation characterization, especially indications of canopy structure and vegetation health and stress situations. Primary vegetation-related data are the hotspot angular width W, and a hotspot factor C that quantifies the magnitude of the hotspot effect. Both quantities are related to the structural parameters of canopy height, foliage size, shape, and leaf area index (LAI). The continuous observations by Triana will allow us to establish time-series of these ecological parameters for all land biomes by longitude, latitude, and wavelength, that form the basis data set for a new global hotspot land vegetation ecology. The hotspot factor C will allow the determination of the enhanced radiant flux reflected from the Earth into space due to the hotspot effect. The hotspot flux enhancement due to the vegetation hotspot effect is estimated to account for about I % of the entire Earth radiative energy balance. C1 Univ Calif Los Alamos Natl Lab, NIS, DO, Los Alamos, NM 87545 USA. RP Gerstl, SAW (reprint author), Univ Calif Los Alamos Natl Lab, NIS, DO, MS-C3233, Los Alamos, NM 87545 USA. NR 10 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3463-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3868 BP 184 EP 194 DI 10.1117/12.373094 PG 11 WC Geology; Geosciences, Multidisciplinary; Remote Sensing; Optics SC Geology; Remote Sensing; Optics GA BP39S UT WOS:000084986600018 ER PT S AU Szymanski, JJ Borel, CC Harberger, QO Smolarkiewicz, P Theiler, J AF Szymanski, JJ Borel, CC Harberger, QO Smolarkiewicz, P Theiler, J BE Cecchi, G Engman, ET Zilioli, E TI Subpixel temperature retrieval with multispectral sensors SO REMOTE SENSING FOR EARTH SCIENCE, OCEAN, AND SEA ICE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Remote Sensing for Earth Science, Ocean, and Sea Ice Applications CY SEP 20-24, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE subpixel analysis; multispectral analysis; temperature measurements; thermal infrared ID SATELLITE AB High-quality, multispectral thermal infrared sensors can, under certain conditions, be used to measure more than one surface temperature in a single pixel. Surface temperature retrieval in general is a difficult task, because even for a single unknown surface, the problem is under-determined. For the example of an N-band sensor, a pixel with two materials at two temperatures will, in principle, have 2(N+1) unknowns (N emissivities and one temperature for each of two materials). In addition, the upwelling path and reflected downwelling radiances must be considered. Split-window (two or more bands) and multi-look (two or more images of the same scene) techniques provide additional information that can be used to reduce the uncertainties in temperature retrieval. Further reduction in the uncertainties is made if the emissivities are known, either a priori (e.g., for water) or by ancillary measurements. Ultimately, if the number of unknowns is reduced sufficiently, the performance of the sensor will determine the achievable temperature sensitivity. This paper will explore the temperature sensitivity for a pixel with Mo temperatures that can be obtained under various assumptions of sensor performance, atmospheric conditions, number of bands, number of looks, surface emissivity knowledge, and surface composition. Results on synthetic data sets will be presented. C1 Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Szymanski, JJ (reprint author), Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Mail Stop C323, Los Alamos, NM 87545 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3463-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3868 BP 478 EP 486 DI 10.1117/12.373105 PG 9 WC Geology; Geosciences, Multidisciplinary; Remote Sensing; Optics SC Geology; Remote Sensing; Optics GA BP39S UT WOS:000084986600049 ER PT S AU Keating, B Max, N AF Keating, B Max, N BE Lischinski, D Larson, GW TI Shadow penumbras for complex objects by depth-dependent filtering of multi-layer depth images SO RENDERING TECHNIQUES '99 SE EUROGRAPHICS LA English DT Proceedings Paper CT 10th Eurographics Workshop on Rendering Techniques CY JUN 21-23, 1999 CL GRANADA, SPAIN AB This paper presents an efficient algorithm for filtering multi-layer depth images (MDIs) in order to produce approximate penumbras. The filtering is performed on a MDI that represents the view from the light source. The algorithm is based upon both ray tracing and the z-buffer shadow algorithm, and is closely related to convolution methods. The method's effectiveness is demonstrated on especially complex objects such as trees, whose soft shadows are expensive to compute by other methods. The method specifically addresses the problem of light-leaking that occurs when tracing rays through discrete representations, and the inability of convolution methods to produce accurate self-shadowing effects. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 32 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, A-1201 VIENNA, AUSTRIA SN 0946-2767 BN 3-211-83382-X J9 SPRING EUROGRAP PY 1999 BP 197 EP 212 PG 16 WC Computer Science, Software Engineering SC Computer Science GA BU30K UT WOS:000175612900018 ER PT J AU Walter, A Overend, RP AF Walter, A Overend, RP TI Financial and environmental incentives: Impact on the potential of BIG-CC technology at the sugar-cane industry SO RENEWABLE ENERGY LA English DT Article DE electricity from biomass; cogeneration; sugar-cane industry; financial incentives; environmental incentives ID BIOMASS AB Brazilian sugar-cane industry has potential to produce 2-4 GW of power at competitive basis and up to 2-3 times more if financial and environmental incentives are given. About 2.0 GW can,be add to the basic potential considering a carbon offset cost lower than 30 $/t C. Some of the instruments that can be used to deploy this potential are tax credits, loans. project loans guarantees, the creation of green markets and external costs evaluation. Biomass Integrated Gasifier-Combined Cycles (BIG-CC) is the technology considered within the analysis presented in this paper. The results are based on simulations considering cogeneration operation mode during the harvest season aid power plant mode otherwise. The potential was calculated considering the Brazilian sugar-cane production during 1995-96 harvest season (230 million tons). (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Estadual Campinas, Mech Engn Coll, Dept Energy, UNICAMP, BR-13083970 Campinas, Brazil. Natl Renewable Energy Lab, Ctr Renewable Chem Technol & Mat, Golden, CO 80401 USA. RP Walter, A (reprint author), Univ Estadual Campinas, Mech Engn Coll, Dept Energy, UNICAMP, BR-13083970 Campinas, Brazil. OI Overend, Ralph/0000-0002-5442-0890 NR 7 TC 1 Z9 1 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-1481 J9 RENEW ENERG JI Renew. Energy PD JAN-APR PY 1999 VL 16 IS 1-4 BP 1045 EP 1048 DI 10.1016/S0960-1481(98)00368-1 PG 4 WC GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY; Energy & Fuels SC Science & Technology - Other Topics; Energy & Fuels GA 125GL UT WOS:000076229000092 ER PT J AU Matson, RJ Carasso, M AF Matson, RJ Carasso, M TI Sustainability, energy technologies, and ethics SO RENEWABLE ENERGY LA English DT Article DE conventional energy technologies; energy and environment energy ethics; energy politics; energy economics; future and energy; intergenerational equity; renewable energy technologies; sustainability AB A study of the economic, social-political, and environmental consequences of using renewable energy technologies (RETs, e.g., photovoltaics, wind, solar thermal, biofuels) as compared to those of conventional energy technologies (CETs, e.g.. oil, coal, gas) would show that RETs are singularly consistent with a whole ethic that is implicit in the concept of sustainability. This paper argues for sustainability as an ethical, as well as a pragmatic, imperative and for RETs as an integral pan of this imperative. It brings to the fore some of the specific current economic, political, and environmental assumptions and practices that are inconsistent with both sustainability and with a rapid deployment of RETs. Reflecting an emerging planetary awareness and a pressing need to come to terms with intra- and intergenerational equity, the concept of sustainability explicitly entails the right of future generations to the same opportunity of access to a healthy ecological future and the finite endowment of the Earth's resources as that of the present generation. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Matson, RJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 7 TC 3 Z9 3 U1 3 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-1481 J9 RENEW ENERG JI Renew. Energy PD JAN-APR PY 1999 VL 16 IS 1-4 BP 1200 EP 1203 DI 10.1016/S0960-1481(98)00482-0 PG 4 WC GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY; Energy & Fuels SC Science & Technology - Other Topics; Energy & Fuels GA 125GL UT WOS:000076229000124 ER PT J AU Holzscheiter, MH Charlton, M AF Holzscheiter, MH Charlton, M TI Ultra-low energy antihydrogen SO REPORTS ON PROGRESS IN PHYSICS LA English DT Review ID ANTIPROTON-POSITRONIUM COLLISIONS; PENNING TRAP; HELIUM-ATOMS; LAMB SHIFT; GRAVITATIONAL ACCELERATION; RELATIVISTIC ANTIHYDROGEN; RADIATIVE RECOMBINATION; PRECISION SPECTROSCOPY; 3-BODY RECOMBINATION; LASER SPECTROSCOPY AB The study of CPT invariance with the highest achievable precision in all particle sectors is of fundamental importance for physics, Equally important is the question of the gravitational acceleration of antimatter. In recent years, impressive progress has been achieved at the Low-Energy Antiproton Ring (LEAR) at CERN in capturing antiprotons in specially designed Penning traps, in cooling them to energies of a few milli-electron volts, and storing them for hours in a small volume of space. Positrons have been accumulated in large numbers in similar traps, and low-energy positron or positronium beams have been generated. Finally, steady progress has been made in trapping and cooling neutral atoms. Thus the ingredients to form antihydrogen at rest are at hand. This report will describe the techniques available to produce, decelerate, and accumulate antiprotons at low energy, how to generate high-density plasmas of low-energy positrons, and how to combine these two species into antihydrogen. Once antihydrogen atoms have been formed, they can be captured in magnetic gradient traps and standard spectroscopic methods applied to interrogate their atomic structure with extremely high precision for comparison with the hydrogen atom, In particular, the 1S-2S transition, with a lifetime of the excited state of 122 ms and thereby a natural linewidth of five parts in 10(16), offers in principle the possibility to directly compare matter and antimatter properties at a level of one part in 10(18). Other quantities of interest, such as the hyperfine structure splitting of the ground state, will also be discussed. Finally, we will give a brief outlook into the future and comment on some of the possible antiproton facilities which could be used to continue this field of research well into the next century. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ London Univ Coll, Dept Phys & Astron, London WC1E 6BT, England. RP Los Alamos Natl Lab, P-23 MS H803, Los Alamos, NM 87545 USA. NR 234 TC 98 Z9 99 U1 2 U2 8 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 JAN PY 1999 VL 62 IS 1 BP 1 EP 60 DI 10.1088/0034-4885/62/1/001 PG 60 WC Physics, Multidisciplinary SC Physics GA 164FD UT WOS:000078451600001 ER PT J AU Fung, J Munne, S Garcia, J Kim, UJ Weier, HUG AF Fung, J Munne, S Garcia, J Kim, UJ Weier, HUG TI Molecular cloning of translocation breakpoints in a case of constitutional translocation t(11;22)(q23;q11) and preparation of probes for preimplantation genetic diagnosis SO REPRODUCTION FERTILITY AND DEVELOPMENT LA English DT Article ID CHROMOSOME-ABNORMALITIES; INTERPHASE CELLS; EWINGS-SARCOMA; MAP; HYBRIDIZATION; EMBRYOS; CONTIG; FISH AB In vitro fertilization (IVF) centres with preimplantation genetic diagnosis (PGD) programmes are often confronted with the problem of identifying chromosomal abnormalities in interphase cells biopsied from preimplantation embryos of carriers of a reciprocal translocation. The present authors have developed a DNA testing based approach to analyse embryos from translocation carriers, and this report describes breakpoint-spanning probes to detect abnormalities in cases of the most common human translocation (i.e. the t(11;22)(q23;q11)). Screening a yeast artificial chromosome (YAC) library for probes covering the respective breakpoint regions in the patient lead to probes for the breakpoint on chromosome 11q23. The physically mapped YAC and bacterial artificial chromosome (BAC) clones from chromosome 22 were then integrated with the cytogenetic map, which allowed localization of the breakpoint on chromosome 22q11 to an interval of less than 84 kb between markers D22S184 and KI457 and to prepare probes suitable for interphase cell analysis, in summary, breakpoint localization could be accomplished in about 4 weeks with additional time needed to optimize probes for use in PGD. C1 Univ Calif San Francisco, Dept Obstet Gynaecol & Reprod Sci, Reprod Genet Unit, San Francisco, CA 94143 USA. Univ Calif Berkeley, EO Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. St Barnabas Med Ctr, Inst Reprod Med & Sci, Livingston, NJ USA. CALTECH, Pasadena, CA 91125 USA. RP Fung, J (reprint author), Univ Calif San Francisco, Dept Obstet Gynaecol & Reprod Sci, Reprod Genet Unit, Box 0720,533 Parnassus Ave, San Francisco, CA 94143 USA. OI Munne, Santiago/0000-0002-1088-5565 NR 25 TC 7 Z9 7 U1 0 U2 0 PU C S I R O PUBLISHING PI COLLINGWOOD PA 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA SN 1031-3613 J9 REPROD FERT DEVELOP JI Reprod. Fertil. Dev. PY 1999 VL 11 IS 1 BP 17 EP 23 DI 10.1071/RD98110 PG 7 WC Developmental Biology; Reproductive Biology; Zoology SC Developmental Biology; Reproductive Biology; Zoology GA 270XC UT WOS:000084561600002 PM 10680998 ER PT B AU Rose, KA Brewer, LW Barnthouse, LW Fox, GA Gard, NW Mendonca, M Munkittrick, KR Vitt, LJ AF Rose, KA Brewer, LW Barnthouse, LW Fox, GA Gard, NW Mendonca, M Munkittrick, KR Vitt, LJ BE DiGiulio, RT Tillitt, DE TI Ecological responses of oviparous vertebrates to contaminant effects on reproduction and development SO REPRODUCTIVE AND DEVELOPMENTAL EFFECTS OF CONTAMINANTS IN OVIPAROUS VERTEBRATES SE SETAC SPECIAL PUBLICATIONS SERIES LA English DT Proceedings Paper CT Pellston Workshop on Reproductive and Developmental Effects of Contaminants in Oviparous Vertebrates CY JUL 13-18, 1997 CL ANACONDA, MT SP Amer Crop Protect, Amer Ind Hlth Council, BASF Corp, Chem Manufacturers Assoc, Dow Chem Co, Eastman Kodak Co, Exxon Corp, Novartis Crop Protect, Procter & Gamble Co, Rhone Poulenc, Rhom & Hass Co, Soap & Detergent Assoc, US EPA, US Fish & Wildlife Serv ID VALDEZ OIL-SPILL; BLEACHED KRAFT MILL; LIFE-HISTORY TRAITS; CATOSTOMUS-COMMERSONI POPULATIONS; LONG-LIVED ORGANISMS; PRINCE-WILLIAM-SOUND; ST-MAURICE RIVER; FISH POPULATIONS; DENSITY-DEPENDENCE; STRIPED BASS C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Munkittrick, Kelly/B-1462-2014 NR 173 TC 7 Z9 7 U1 1 U2 2 PU SETAC PRESS PI PENSACOLA PA 1010 N 12TH AVE, PENSACOLA, FL 32501 USA BN 1-880611-37-6 J9 SETAC SP P PY 1999 BP 225 EP 281 PG 57 WC Environmental Sciences; Reproductive Biology; Zoology SC Environmental Sciences & Ecology; Reproductive Biology; Zoology GA BP34G UT WOS:000084757700004 ER PT J AU Chemerisov, SD Werst, DW Trifunac, AD AF Chemerisov, SD Werst, DW Trifunac, AD TI Photoionization and energy-dependent photochemistry of hydrocarbons in ZSM5 SO RESEARCH ON CHEMICAL INTERMEDIATES LA English DT Review ID PHOTOINDUCED ELECTRON-TRANSFER; LASER FLASH-PHOTOLYSIS; RADICAL CATIONS; DIFFUSE-REFLECTANCE; ZEOLITE-Y; STILBENE; EPR; ISOMERIZATION; SPECTROSCOPY; ANTHRACENE AB Photostimulated processes involving unsaturated hydrocarbon molecules adsorbed in ZSM5 were investigated under oxygen-free conditions. The primary products of photoionization (radical cations) and neutral photochemistry (radicals) were observed by EPR spectroscopy. Photoionization is a multiphoton process over the wavelength range studied (248-600 nm). Radical products indicate single-photon C-C bond dissociation and multiphoton C-H bond dissociation reactions of neutral excited states. The implications for applications of zeolites in photocatalysis are discussed. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Chemerisov, SD (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 32 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0922-6168 J9 RES CHEM INTERMEDIAT JI Res. Chem. Intermed. PY 1999 VL 25 IS 6 BP 583 EP 597 DI 10.1163/156856799X00572 PG 15 WC Chemistry, Multidisciplinary SC Chemistry GA 246MP UT WOS:000083167800006 ER PT B AU Jackson, NB AF Jackson, NB GP CHEMICAL SCIENCES ROUNDTABLE CHEMICAL SCIENCES ROUNDTABLE TI Partnering at the national laboratories: Catalysis as a case study SO RESEARCH TEAMS AND PARTNERSHIPS: TRENDS IN THE CHEMICAL SCIENCES: REPORT OF A WORKSHOP LA English DT Proceedings Paper CT 3rd Chemical Sciences Roundtable Workshop CY MAY 02-03, 1999 CL IRVINE, CA C1 Sandia Natl Labs, Livermore, CA 94550 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU NATL ACADEMIES PRESS PI WASHINGTON PA 2101 CONSTITUTION AVE, WASHINGTON, DC 20418 USA BN 0-309-06827-4 PY 1999 BP 97 EP 106 PG 10 WC Chemistry, Multidisciplinary; Management SC Chemistry; Business & Economics GA BX17Y UT WOS:000184541500008 ER PT J AU Thanos, PK Okajima, S Tiangco, DA Terzis, JK AF Thanos, PK Okajima, S Tiangco, DA Terzis, JK TI Insulin-like growth factor-I promotes nerve regeneration through a nerve graft in an experimental model of facial paralysis SO RESTORATIVE NEUROLOGY AND NEUROSCIENCE LA English DT Article DE blink reflex; axon; myelin; osmotic pump; neurotrophic; reinnervation ID RAT SCIATIC-NERVE; MESSENGER-RNAS; DIABETIC NEUROPATHY; NEUROTROPHIC FACTOR; PARKINSONS-DISEASE; PERIPHERAL-NERVES; NEURITE FORMATION; SENSORY NEURONS; ADULT-RAT; IGF-I AB Among the pathological sequelae of facial paralysis is a Paralytic eye. Apart from the psychological and aesthetic deficits, facial paralysis if left untreated can lead to dryness, ulceration and eventual blindness. Although numerous restorative microsurgical approaches have been introduced to address the sequelae of this problem, complete restoration of function to denervated facial muscles remains elusive. Utilizing the rat model of facial paralysis the present research has as an objective to examine a dual treatment approach. Specifically, this study combined the current microsurgical treatment of the cross-facial nerve graft with local administration of insulin-like growth factor I The efficacy of this combined approach (cross-facial nerve graft + IGF-I) was assessed in the following ways: (a) behavior measurement of the blink response and (b) histomorphometry light and electron microscopy of the entire nerve graft. These data will help provide insight into the restoration of facial muscle function after trauma and assist in the future development of more potent treatment strategies. The local administration of IGF-I (50 mu g/ml) to the cross-facial nerve graft was found to restore the blink response faster and to strengthen the degree of eye closure. Light microscopy examination revealed that IGF-I significantly enhanced axonal regeneration within a nerve graft (a 22 % increase in the mean number of axons), and increased the mean nerve fiber diameter and myelin thickness. Electron microscopy assessment of the nerve grafts demonstrated that the IGF-I treated grafts possessed a greater density of microtubules, which were evenly distributed within the axoplasm. C1 Eastern Virginia Med Sch, Dept Surg, Microsurg Res Ctr, Norfolk, VA 23507 USA. SUNY Stony Brook, Dept Neurosci, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Med, Ctr Imaging & Neurosci, Upton, NY 11973 USA. Kyoto Prefectural Univ Med, Dept Orthoped Surg, Kyoto, Japan. RP Terzis, JK (reprint author), Eastern Virginia Med Sch, Dept Surg, Microsurg Res Ctr, Norfolk, VA 23507 USA. NR 72 TC 9 Z9 9 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA VAN DIEMENSTRAAT 94, 1013 CN AMSTERDAM, NETHERLANDS SN 0922-6028 J9 RESTOR NEUROL NEUROS JI Restor. Neurol. Neurosci. PY 1999 VL 15 IS 1 BP 57 EP 71 PG 15 WC Neurosciences SC Neurosciences & Neurology GA 253QU UT WOS:000083567900006 ER PT J AU Wishnow, EH Leung, A Gush, HP AF Wishnow, EH Leung, A Gush, HP TI Cryogenic multiple reflection absorption cell and Fourier transform spectrometer system for the far infrared SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID SPECTRUM; HYDROGEN; H-2; MIXTURES AB A far-infrared system used to measure weak absorption spectra of gases at pressures up to a few atmospheres and at temperatures as low as 20 K is described. The principal component is a multiple reflection mirror cell, cooled either with liquid nitrogen or with the boil-off gas from liquid helium. The cell, of 35 l volume, has an f/10 optical beam and a pathlength which can be varied from 4 to 60 m. At the longest pathlength diffraction limits the lowest usable frequency to 20 cm(-1). The cell is coupled to a Fourier transform spectrometer and a 1.6 K bolometer. The apparatus has been used in a detailed study of the collision-induced pure translational band of H-2, and the translation-rotation bands of N-2 and N-2-Ar mixtures. (C) 1999 American Institute of Physics. [S0034-6748(99)02001-8]. C1 Univ British Columbia, Dept Phys, Vancouver, BC V6T 1Z1, Canada. RP Wishnow, EH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Div V, POB 808, Livermore, CA 94551 USA. NR 33 TC 5 Z9 5 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 23 EP 31 DI 10.1063/1.1149537 PN 1 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 159RB UT WOS:000078186800006 ER PT J AU Pelekhov, DV Becker, JB Nunes, G AF Pelekhov, DV Becker, JB Nunes, G TI Atomic force microscope for operation in high magnetic fields at millikelvin temperatures SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID SCANNING-TUNNELING-MICROSCOPE; NORMAL-METAL RINGS; ULTRAHIGH-VACUUM; GRAPHITE; INTERFEROMETER; CONDUCTANCE; RESOLUTION; SURFACE; LATTICE; IMAGES AB We report on the design and performance of an atomic force microscope which operates at temperatures down to 20 mK and in magnetic fields up to 9 T. The scan range at low temperatures is 4 mu m x 4 mu m. The instrument features a piezoelectric linear motor for vertical coarse approach, and a horizontal sample translation stage with a 2 mm x 2 mm range. A fiber interferometer is used to detect the force-sensing cantilever displacement. The performance demonstrated includes the ability to detect single atomic steps on a graphite surface at 4.2 K and the ability to locate and image nanometer scale electronic devices at millikelvin temperatures. (C) 1999 American Institute of Physics. [S0034-6748(99)01501-4]. C1 Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. RP Pelekhov, DV (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Nunes, Jr., Geoffrey/M-1284-2013 OI Nunes, Jr., Geoffrey/0000-0002-6076-3400 NR 34 TC 23 Z9 23 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 114 EP 120 DI 10.1063/1.1149551 PN 1 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 159RB UT WOS:000078186800022 ER PT J AU Lee, HR Kupperman, D Yun, W Cai, Z Rodrigues, W AF Lee, HR Kupperman, D Yun, W Cai, Z Rodrigues, W TI X-ray microdiffraction studies to measure strain fields in a metal matrix composite SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID MICROSCOPE AB An x-ray diffraction microscope (XDM) has been used to map the strain field in a fiber-reinforced composite material. The monochromatic x-ray (11 keV) beam was focused by a phase zone plate to produce a focal spot of 1 x 4 mu m(2) on the specimen. The microfocusing method using a zone plate enables the XDM to produce a high spatial resolution of;1 mm. The change in the peak position of diffraction patterns due to interatomic spacing change, caused by stress in the sample, was measured by using a two-dimensional charge coupled device detector. The radial residual strain field in the fiber-reinforced composite (SCS-6/Ti-14Al-21Nb) was measured from diffraction patterns with a sensitivity of similar to 10(-4) and an average standard deviation of 9.4 x 10(-5). [S0034-6748(99)02901-9]. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA. RP Lee, HR (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 175 EP 177 DI 10.1063/1.1149561 PN 1 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 159RB UT WOS:000078186800032 ER PT J AU Wurden, GA Peterson, BJ AF Wurden, GA Peterson, BJ TI Development of imaging bolometers for long-pulse MFE experiments (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SYSTEM; DESIGN AB We have developed the concept of an imaging bolometer, capable of operation with 100's of individual channels, while relying on optical (infrared) readout of the temperature rise in a thin foil. A thin gold foil (0.5-5 mu m thick) is sandwiched between pieces of copper. The copper mask (a large thermal mass) has a hole pattern drilled into it to form many "individual pixels," effectively forming many separate sensors. This segmented foil/mask combination is exposed on its front side to plasma radiation through a cooled pinhole camera geometry. Simultaneously, a high-resolution infrared camera monitors any temperature change on the backside of the thin foil. A sensitive infrared (IR) camera views the foil through an IR telescope/periscope system, and is shielded from the magnetic and nuclear radiation fields, either by distance and/or material shielding. A simple time-dependent design algorithm, using 1D heat transport to a cold boundary, has been written in MathCad, which allows us to select optimal material and geometries to match the expected plasma conditions. We have built a compact prototype with 149 channels, and tested it successfully both in a vacuum test stand in the laboratory, and on a plasma in the CHS at the National Institute for Fusion Science, subjecting it to electron cyclotron heated and neutral beam injection heated conditions. A water-cooled version has been built for the new LHD. Since the IR imaging bolometer uses only metal parts near the plasma, and has no need for wiring or wiring feedthrus, it is intrinsically radiation hard, and has direct application to ignition device to test engineering concepts (ITER), or ITER-class experiments. (C) 1999 American Institute of Physics. [S0034-6748(99)66101- 9]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Inst Fus Sci, Toki, Japan. RP Wurden, GA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 12 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 255 EP 259 DI 10.1063/1.1149441 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900002 ER PT J AU Perry, MD Sefcik, JA Cowan, T Hatchett, S Hunt, A Moran, M Pennington, D Snavely, R Wilks, SC AF Perry, MD Sefcik, JA Cowan, T Hatchett, S Hunt, A Moran, M Pennington, D Snavely, R Wilks, SC TI Hard x-ray production from high intensity laser solid interactions (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID FEMTOSECOND LASER; ELECTRONS; TARGETS AB Intense laser (> 10(21) W/cm(2)) driven hard x-ray sources offer a new alternative to conventional electron accelerator bremsstrahlung sources. These laser driven sources offer considerable simplicity in design and cost advantage for multiple axis views and have the potential for much higher spatial and temporal resolution than is achievable with accelerator sources. We have begun a series of experiments using the Petawatt laser system at LLNL to determine the potential of these sources for radiography applications. Absolutely calibrated spectra extending to 20 MeV and high resolution radiographs through a rho r greater than or equal to 150 g/cm(2) have been obtained. The physics of these sources and the scaling relationships and laser technology required to provide the dose levels necessary for radiography applications will be discussed. Diagnostics of the laser produced electrons and photons will be addressed. (C) 1999 American Institute of Physics. [S0034-6748(99)66201- 3]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Perry, MD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Cowan, Thomas/A-8713-2011 OI Cowan, Thomas/0000-0002-5845-000X NR 6 TC 57 Z9 59 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 265 EP 269 DI 10.1063/1.1149442 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900004 ER PT J AU Fehl, DL Muron, DJ Leeper, RJ Chandler, GA Deeney, C Stygar, WA Spielman, RB AF Fehl, DL Muron, DJ Leeper, RJ Chandler, GA Deeney, C Stygar, WA Spielman, RB TI Absolute, soft x-ray calorimetry on the Z facility at Sandia National Laboratories (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID INTENSE AB Simple and reliable x-ray fluence measurements, in addition to time-resolved diagnostics, are needed to understand the physics of hot Z-pinch plasmas. A commercially available laser calorimeter has been modified for measuring soft x-ray fluence from the Z facility at Sandia National Laboratories. The x-ray absorber of this calorimeter is an aluminum disk, attached to a two-dimensional thermopile and surrounded by an isoperibol shroud. The time integral and the maximum of the thermopile voltage signal are both proportional to the x-ray energy deposited. Data are collected for 90 s, and the instrument has, thus far, been used in the 1-25 mJ range. A wider dynamic measuring range for x-ray fluence (energy/area) can be achieved by varying the area of the defining aperture. The calorimeter is calibrated by an electrical substitution method. Calibrations are performed before and after each x-ray experiment on the Z facility. The calibration of the time integral of the thermopile voltage versus energy deposited (or the peak of thermopile voltage versus energy deposited) is linear with zero intercept at the 95% confidence level. The irreproducibility of the calibration is < 2%, and the imprecision in the measurement of the incident x-ray energy (inferred from signal noise and the calibration) is estimated to be similar to 0.9 mJ (95% confidence level). The systematic uncertainty (inaccuracy), due to correctable baseline shifts, is estimated at +/- 10%. Comparisons have been made of the calorimeter to time-resolved x-ray diagnostics, e.g., bolometers and x-ray diode arrays, by integrating the flux measured by such instruments over time. (C) 1999 American Institute of Physics. [S0034-6748(99)70101-2]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fehl, DL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 15 Z9 19 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 270 EP 275 DI 10.1063/1.1149515 PN 2 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900005 ER PT J AU Beiersdorfer, P Lopez-Urrutia, JRC Springer, P Utter, SB Wong, KL AF Beiersdorfer, P Lopez-Urrutia, JRC Springer, P Utter, SB Wong, KL TI Spectroscopy in the extreme ultraviolet on an electron beam ion trap SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID HELIUM ISOELECTRONIC SEQUENCE; CORRECTED CONCAVE GRATINGS; X-RAY SPECTROMETER; LAMB SHIFT AB A compact grazing-incidence spectrometer was implemented on the Livermore electron beam ion trap facility for spectral measurements in the extreme ultraviolet spectral region. The spectrometer employed a 1200 rho/mm grating designed for flat-field focusing and a charge coupled device camera for readout. The instrument was used to measure line emission in the range from 25 to 220 Angstrom with a resolving power as high as 600. The performance and calibration of the instrument is described and spectra from highly charged nitrogen and iron ions are presented. Measurements of the K-shell spectrum of He-like N5+ are presented that confirm earlier wavelength determinations and illustrate the accuracy achievable with the instrument. Our measurement suggests a change in the line identifications of the forbidden He-like N5+ transition 1s2s S-3(1) --> (1)s(2) S-1(0) and of the Li-like N4+ collisional satellite transition 1s2s2p P-2(3/2) --> 1s(2)2s S-2(1/2) observed on the Alcator C-Mod tokamak. (C) 1999 American Institute of Physics. [S0034-6748(99)51801-7]. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. RP Beiersdorfer, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. EM beiersdorfer@llnl.gov RI Crespo Lopez-Urrutia, Jose R./F-7069-2011 OI Crespo Lopez-Urrutia, Jose R./0000-0002-2937-8037 NR 23 TC 57 Z9 58 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 276 EP 279 DI 10.1063/1.1149324 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900006 ER PT J AU Brown, GV Beiersdorfer, P Widmann, K AF Brown, GV Beiersdorfer, P Widmann, K TI Wide-band, high-resolution soft x-ray spectrometer for the Electron Beam Ion Trap SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SPECTRA; EMISSION; IRON AB We have constructed two wide-band, high-resolution vacuum flat crystal spectrometers and implemented them on the Electron Beam Ion Trap located at the Lawrence Livermore National Laboratory. Working in unison, these spectrometers can measure an x-ray bandwidth less than or equal to 9 Angstrom in the soft x-ray region below 21 Angstrom. In order to achieve this large bandwidth each spectrometer houses either two 125 mm x 13 mm x 2 mm RAP (rubidium acid phthalate, 2d = 26.121 Angstrom), two 114 mm x 13 mm x 2 mm TlAP (thallium acid phthalate, 2d = 25.75 Angstrom) crystals, or some combination thereof, for dispersion and two position sensitive proportional counters for detection of x rays. The spectrometers are used to measure wavelengths and relative intensities of the L-shell line emission from Fe XVII-XXIV for comparison with spectra obtained from astrophysical and laboratory plasmas. The wide wavelength coverage attainable by these spectrometers makes it possible to measure all the L-shell emission from a given iron ion species simultaneously. (C) 1999 American Institute of Physics. [S0034-6748(99)59801- 8]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Brown, GV (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 26 TC 51 Z9 52 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 280 EP 283 DI 10.1063/1.1149339 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900007 ER PT J AU Utter, SB Brown, GV Beiersdorfer, P Clothiaux, EJ Podder, NK AF Utter, SB Brown, GV Beiersdorfer, P Clothiaux, EJ Podder, NK TI Grazing-incidence measurements of L-shell line emission from highly charged Fe in the soft x-ray region SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID ELECTRON-BEAM; SPECTROMETER; POLARIZATION; SPECTROSCOPY AB Line emission from highly charged ions in the soft x-ray region represents an important diagnostic for high-temperature plasmas. The wavelength region of 10-30 Angstrom is occupied by lines from the K-shell transitions in N through Ne and L-shell transitions in Ti through Ni. Crystal spectrometers have previously been used to investigate Fe line radiation under well controlled conditions using the LLNL electron beam ion trap facility in this wavelength region. To complement this work we have instituted a grazing-incidence spectrometer with a variable line-spaced, concave grating and a flat field of focus which is suited for a multichannel detector. Simultaneous observations of the Ne-like Fe16+ n = 3 --> 2 transitions were made with this instrument and a flat-crystal spectrometer in order to establish the linear polarization of the Fe XVII lines. We present a description of the grating spectrometer and discuss its performance in comparison with Rowland circle based grazing incidence instruments. (C) 1998 American Institute of Physics. [S0034-6748(99)70201- 7]. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94551 USA. Auburn Univ, Dept Phys, Auburn, AL 36830 USA. RP Utter, SB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94551 USA. NR 9 TC 43 Z9 43 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 284 EP 287 DI 10.1063/1.1149511 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900008 ER PT J AU Utter, SB Beiersdorfer, P Lopez-Urrutia, JRC Trabert, E AF Utter, SB Beiersdorfer, P Lopez-Urrutia, JRC Trabert, E TI Implementation of a normal incidence spectrometer on an electron beam ion trap SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID KR AB Spectroscopic instrumentation is one of the keys to the exploration of high-temperature plasmas. The electron beam ion trap (EBIT) can serve as a tool for precise studies of highly charged ions in the laboratory and can help in setting spectroscopic standards for plasma studies. Recent efforts have focused on investigating the EUV, vacuum ultraviolet (VUV), and UV regimes. We present here the implementation of a 1 m normal incidence spectrometer for use on the Lawrence Livermore National Laboratory high-energy EBIT (Super-EBIT) for spectral analysis of line emission of highly charged ions. Using two different gratings, our study encompasses a wide range of wavelengths spanning the VUV through the visible. Examples of measurements of optical spectra from krypton and argon are given. (C) 1999 American Institute of Physics. [S0034-6748(99)51901-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94551 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Auburn Univ, Dept Phys, Auburn, AL 36839 USA. RP Utter, SB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94551 USA. RI Crespo Lopez-Urrutia, Jose R./F-7069-2011 OI Crespo Lopez-Urrutia, Jose R./0000-0002-2937-8037 NR 13 TC 14 Z9 14 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 288 EP 291 DI 10.1063/1.1149325 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900009 ER PT J AU Bitter, M Hill, KW Roquemore, AL Beiersdorfer, P Kahn, SM Elliott, SR Fraenkel, B AF Bitter, M Hill, KW Roquemore, AL Beiersdorfer, P Kahn, SM Elliott, SR Fraenkel, B TI Imaging x-ray crystal spectrometers for the National Spherical Torus Experiment SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID POLARIZATION; PLASMAS; BEAM; IONS AB A new type of high-resolution x-ray imaging crystal spectrometers is described for implementation on the National Spherical Torus Experiment (NSTX) to provide spatially and temporally resolved data on the ion temperature, toroidal and poloidal plasma rotation, electron temperature, impurity ion-charge state distributions, and impurity transport. These data are derived from observations of the satellite spectra of heliumlike argon, Ar XVII, which is the dominant charge state for electron temperatures in the range from 0.4 to 3.0 keV and which is accessible to NSTX. Experiments at the Torus Experiment for Technology Oriented Research (TEXTOR) demonstrate that a throughput of 2 x 10(5) photons/s (corresponding to the count-rate limit of the present detectors) can easily be obtained with small, nonperturbing argon gas puffs of less than 1 x 10(-3) Torr rho/s, so that it is possible to record spectra with a small statistical error and a good time resolution (typically 50 and 1 ms in some cases). Employing a novel design, which is based on the imaging properties of spherically bent crystals, the spectrometers will provide spectrally and spatially resolved images of the plasma for all experimental conditions, which include ohmically heated discharges as well as plasmas with rf and neutral-beam heating. The conceptual design, experimental results on the focusing properties, and relevant spectral data from TEXTOR are presented. (C) 1999 American Institute of Physics. [S0034-6748(99)60301- X]. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94550 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP Bitter, M (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 18 TC 53 Z9 58 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 292 EP 295 DI 10.1063/1.1149344 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900010 ER PT J AU Fraenkel, BS Bitter, M AF Fraenkel, BS Bitter, M TI New concepts for x-ray spectroscopy of tokamak plasmas SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB The throughput of Bragg crystal spectrometers with two-dimensionally curved crystals has been computed and is found to be much larger than the throughput of conventional Johann spectrometers with cylindrically bent crystals. Special attention was given to spectrometers with spherically and toroidally bent crystals which provide, in addition to a high throughput, good spectral and spatial resolution. These spectrometers should meet the growing diagnostic requirements for present and future large tokamaks. (C) 1999 American Institute of Physics. [S0034-6748(99)74501- 6]. C1 Hebrew Univ Jerusalem, Racah Inst Phys, Lab Xray & VUV Spect, IL-91904 Jerusalem, Israel. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. RP Fraenkel, BS (reprint author), Hebrew Univ Jerusalem, Racah Inst Phys, Lab Xray & VUV Spect, IL-91904 Jerusalem, Israel. NR 7 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 296 EP 298 DI 10.1063/1.1149467 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900011 ER PT J AU Lee, SG Hwang, SM Bitter, M AF Lee, SG Hwang, SM Bitter, M TI X-ray crystal spectrometer for the HANBIT mirror machine SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID ION TEMPERATURE AB Design study of an x-ray crystal spectrometer for the HANBIT mirror machine is presented. The x-ray emissivity of HANBIT plasmas is rather low as a result of the low values of the electron temperature and density. The design difficulty from the low x-ray emissivity can be overcome by utilizing a vacuum spectrometer sightline parallel to the long axial length of HANBIT and using an x-ray sensitive vacuum charge-coupled device camera as a detector. (C) 1999 American Institute of Physics. [S0034-6748(99)70301-1]. C1 Korea Basic Sci Inst, Taejon 305333, South Korea. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lee, SG (reprint author), Korea Basic Sci Inst, Taejon 305333, South Korea. NR 12 TC 5 Z9 5 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 299 EP 301 DI 10.1063/1.1149516 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900012 ER PT J AU Nash, T Derzon, M Leeper, R Jobe, D Hurst, M Seamen, J AF Nash, T Derzon, M Leeper, R Jobe, D Hurst, M Seamen, J TI Spatially and temporally resolved crystal spectrometer for diagnosing high-temperature pinch plasmas on Z SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID HIGH-POWER AB We have developed a spatially and temporally resolved crystal spectrometer for analyzing a variety of pinch experiments on Z. The spectrometer uses a convex curved crystal to disperse spectra onto a flat microchannel plate (MCP) framing camera detector. A single wide, 1 cm, strip on the MCP is gated to provide temporal resolution. The spectral range governed by the 4 cm length of the MCP strip varies with the central Bragg angle and crystal. For a KAP crystal a typical range is 1500-2000 eV. This range can be shifted by translating the crystal along the optical axis to access different Bragg angles. The spectrometer can therefore measure K shell spectra of a wide variety of elements such as Al, Ti, and Fe. The short 1 cm width of the strip is spatially resolved with an imaging cross slit. With a 500 mu m cross slit and magnification 1 the spatial resolution at the pinch is 1 mm. The instrument may also be fielded with seven time frames using a seven strip-line microchannel plate as the detector by sacrificing the spatial resolution. We will present data obtained from an aluminum pinch on Z. (C) 1999 American Institute of Physics. [S0034-6748(99)54101-4]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Nash, T (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 17 Z9 18 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 302 EP 304 DI 10.1063/1.1149502 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900013 ER PT J AU MacFarlane, JJ Derzon, MS Nash, TJ Chandler, GA Peterson, DL AF MacFarlane, JJ Derzon, MS Nash, TJ Chandler, GA Peterson, DL TI On the transparency of foam in low-density foam Z-pinch experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB Z-pinch experiments have been performed on the SATURN and Z machines at Sandia National Laboratories to study physics issues related to x-ray radiation generation and inertial confinement fusion. Some of these experiments utilize a CH foam located on-axis to convert energy to radiation and act as a radiative transfer volume. A significant issue for foam Z-pinch experiments is the transparency of the heated foam as a function of time and wavelength. Foam transparency will be important in future foam Z-pinch experiments both because it influences the time-dependent radiation field seen by an inertial confinement fusion capsule embedded in the foam, and because it is an important factor in making high-resolution spectral measurements of a capsule or tracers embedded in the foam. In this article, we describe results from simulations and experiments which address the issue of foam transparency. We discuss imaging data from one Z experiment in which x-ray emission from a half-Au/half-CH disk located at the bottom of a 1-cm-tall, 14 mg/cc TPX foam is observed. Simulation results predicting CH foam optical depths as a function of plasma conditions are presented. In addition, we present results from spectral calculations which utilize 2D magnetohydrodynamic (MHD) simulation predictions for the time-dependent foam conditions. Our results indicate that the observed x-ray framing camera images are consistent with early-time (several ns prior to stagnation) foam electron temperatures of greater than or similar to 30 eV, which is somewhat hotter than the foam electron temperatures predicted from the 2D MHD simulations at early times. (C) 1999 American Institute of Physics. [S0034-6748(99)75801- 6]. C1 Prism Computat Sci Inc, Madison, WI 53703 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP MacFarlane, JJ (reprint author), Prism Computat Sci Inc, Madison, WI 53703 USA. NR 6 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 323 EP 327 DI 10.1063/1.1149476 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900019 ER PT J AU Karney, CFF Stotler, DP Skinner, CH Terry, JL Pappas, DA AF Karney, CFF Stotler, DP Skinner, CH Terry, JL Pappas, DA TI Effect of reflection on H-alpha emissions in Alcator C-MOD SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SIMULATION AB In order to explain anomalous intensity ratios which have been observed in Alcator C-MOD, the H alpha emissions in that experiment have been modeled with the DEGAS 2 code including the effects of wall reflection. By assuming that the first wall has different reflection coefficients for the two polarizations, we have qualitatively reproduced the observed anomaly. (C) 1999 American Institute of Physics. [S0034-6748(99)60601-3]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Ctr Plasma Fus, Cambridge, MA 02139 USA. RP Karney, CFF (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Karney, Charles/C-1371-2013; Stotler, Daren/J-9494-2015 OI Karney, Charles/0000-0002-5006-5836; Stotler, Daren/0000-0001-5521-8718 NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 344 EP 346 DI 10.1063/1.1149347 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900024 ER PT J AU Stotler, DP Skinner, CH Karney, CFF AF Stotler, DP Skinner, CH Karney, CFF TI Spectroscopic measurements of hydrogen ion temperature during divertor recombination SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID ALCATOR C-MOD; SIMULATION AB We explore the possibility of using the neutral H-alpha spectral line profile to measure the ion temperature, T-i, in a recombining plasma. Since the H-alpha emissions due to recombination are larger than those due to other mechanisms, interference from nonrecombining regions contributing to the chord integrated data is insignificant. A Doppler and Stark broadened H-alpha spectrum is simulated by the DEGAS 2 neutral transport code using assumed plasma conditions. The application of a simple fitting procedure to this spectrum yields an electron density, n(e), and T-i consistent with the assumed plasma parameters if the spectrum is dominated by recombination from a region of modest n e variation. General measurements of the ion temperature by H-alpha spectroscopy appear feasible within the context of a model for the entire divertor plasma. (C) 1999 American Institute of Physics. [S0034-6748(99)68601-4]. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Stotler, DP (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Karney, Charles/C-1371-2013; Stotler, Daren/J-9494-2015 OI Karney, Charles/0000-0002-5006-5836; Stotler, Daren/0000-0001-5521-8718 NR 19 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 347 EP 350 DI 10.1063/1.1149431 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900025 ER PT J AU Hillis, DL Morgan, PD Ehrenberg, JK Groth, M Stamp, MF von Hellermann, M Kumar, V AF Hillis, DL Morgan, PD Ehrenberg, JK Groth, M Stamp, MF von Hellermann, M Kumar, V TI Tritium concentration measurements in the Joint European Torus divertor by optical spectroscopy of a Penning discharge SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID FIBERS AB Obtaining precision measurements of the relative concentrations of hydrogen, deuterium, tritium, and helium in the divertor of a tokamak is an important task for nuclear fusion research. Control of the deuterium-tritium isotopic ratio while limiting the helium ash content in a fusion plasma are key factors for optimizing the fuel burn in a fusion reactor, like the International Tokamak Experimental Reactor. A diagnostic technique has been developed to measure the deuterium-tritium isotopic ratio in the divertor of the Joint European Torus with a species-selective Penning vacuum gauge. The Penning discharge provides a source of electrons to excite the neutral hydrogen isotopes in the pumping duct. Subsequently, the visible light from the hydrogen isotopes is collected in an optical fiber bundle, transferred away from the tokamak into a low radiation background area, and analyzed in a high resolution Czerny-Turner spectrometer, which is equipped with a fast charge coupled device camera for optical detection. The intensity of the observed line emission (D-alpha - 6561.03 Angstrom and T-alpha - 6560.44 Angstrom) is directly proportional to the partial pressure of each gas found in the divertor. The line intensity of each isotope is calibrated as a function of pressure. The ratio of the line intensities thus provides a direct measurement of the deuterium-tritium isotopic ratio. The lower limit for the determination of the deuterium-tritium isotopic ratio is about 0.5%. The applicable pressure range for this system is from 10(-5) to a few times 10(-3) mbar. (C) 1999 American Institute of Physics. [S0034-6748(99)57001- 9]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Inst Plasma Res, Bhat 382428, Gandhinagar, India. RP Hillis, DL (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Groth, Mathias/G-2227-2013 NR 8 TC 26 Z9 26 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 359 EP 362 DI 10.1063/1.1149301 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900028 ER PT J AU May, MJ Finkenthal, M Soukhanovskii, V Stutman, D Moos, HW Pacella, D Mazzitelli, G Fournier, K Goldstein, W Gregory, B AF May, MJ Finkenthal, M Soukhanovskii, V Stutman, D Moos, HW Pacella, D Mazzitelli, G Fournier, K Goldstein, W Gregory, B TI Benchmarking atomic physics models for magnetically confined fusion plasma physics experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SPECTROMETER; IMPURITIES; TOKAMAKS AB In present magnetically confined fusion devices, high and intermediate Z impurities are either puffed into the plasma for divertor radiative cooling experiments or are sputtered from the high Z plasma facing armor. The beneficial cooling of the edge as well as the detrimental radiative losses from the core of these impurities can be properly understood only if the atomic physics used in the modeling of the cooling curves is very accurate. To this end, a comprehensive experimental and theoretical analysis of some relevant impurities is undertaken. Gases (Ne, Ar, Kr, and Xe) are puffed and nongases are introduced through laser ablation into the FTU tokamak plasma. The charge state distributions and total density of these impurities are determined from spatial scans of several photometrically calibrated vacuum ultraviolet and x-ray spectrographs (3 - 1600 Angstrom), the multiple ionization state transport code transport code (MIST) and a collisional radiative model. The radiative power losses are measured with bolometery, and the emissivity profiles were measured by a visible bremsstrahlung array. The ionization balance, excitation physics, and the radiative cooling curves are computed from the Hebrew University Lawrence Livermore atomic code (HULLAC) and are benchmarked by these experiments. (Supported by U. S. DOE Grant No. DE-FG02-86ER53214 at JHU and Contract No. W-7405-ENG-48 at LLNL.) (C) 1999 American Institute of Physics. [S0034-6748(99)65201- 7]. C1 Johns Hopkins Univ, Dept Phys & Astron, Plasma Spect Grp, Baltimore, MD 21218 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. FTU, Assoc EURATOM ENEA Fus, Frascati, Italy. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. INRS, Varennes, PQ, Canada. CCFM, Varennes, PQ, Canada. RP May, MJ (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Plasma Spect Grp, Baltimore, MD 21218 USA. RI Stutman, Dan/P-4048-2015 NR 16 TC 9 Z9 9 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 375 EP 378 DI 10.1063/1.1149410 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900032 ER PT J AU Ramsey, AT Diesso, M AF Ramsey, AT Diesso, M TI Abel inversions: Error propagation and inversion reliability SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB Inversion of chordally integrated data to infer the profile of a plasma parameter (plasma density, radiated power, or, in our case, the visible continuum from bremsstrahlung) propagates errors from outer shells inward as the inversion progresses. If the inversion is done by a matrix technique, error propagation can likewise be determined by a matrix technique. Where other considerations make the matrix method undesirable, there is no clearly defined analytical method to test the reliability of the inversion. We have solved this problem by taking real data from the Tokamak Fusion Test Reactor (TFTR) visible bremsstrahlung (VB) diagnostic, applying normally distributed random noise of a known mean value, and inverting the signal. When we have done this hundreds of times at all points in the profile, we can clearly track the error propagation. At the plasma center, for example, the error is several times the average error in the relative (chord to chord) calibration of the system. This error multiplier is a powerful generalization; it depends little on the details of the inversion, and almost entirely on the profile shape. For the TFTR VB profile it ranges from 2 to 4 for most types of plasma. We have also looked at the damping of the inversion error from an error in a single chord; this damping can be rather fast in some cases. (C) 1999 American Institute of Physics. [S0034-6748(99)60701-8]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Ramsey, AT (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 15 Z9 16 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 380 EP 383 DI 10.1063/1.1149348 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900034 ER PT J AU Brooks, NH Jensen, TH Colchin, RJ Maingi, R Wade, MR Finkenthal, DF Naumenko, N Tugarinov, S AF Brooks, NH Jensen, TH Colchin, RJ Maingi, R Wade, MR Finkenthal, DF Naumenko, N Tugarinov, S TI Partial pressure measurements with an active spectrometer SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID DEUTERIUM ENVIRONMENT; DIVERTOR AB Partial pressure neutral gas measurements have been made using a commercial Penning gauge in conjunction with an "active spectrometer." In prior work utilizing band pass filters and conventional spectrometers, trace concentrations of the hydrogen isotopes H, D, T and of the noble gases He, Ne, and Ar were determined from characteristic spectral lines in the light emitted by the neutral species of these elements. For all the elements mentioned, the sensitivity was limited by spectral contamination from a pervasive background of molecular hydrogen radiation. The active spectrometer overcomes this limitation by means of a digital lock-in method and correlation with reference spectra. Preliminary measurements of an admixture containing a trace amount of neon in deuterium show better than a factor of 20 improvement in sensitivity over conventional techniques. This can be further improved by correlating the relative intensities of multiple lines to sets of reference spectra. (C) 1999 American Institute of Physics. [S0034-6748(99)57201- 8]. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Palomar Coll, San Marcos, CA 92069 USA. Inst Atom & Mol Phys, Minsk 220072, Byelarus. TRINITI, Troitsk 142092, Russia. RP Brooks, NH (reprint author), Gen Atom Co, San Diego, CA 92186 USA. NR 10 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 423 EP 426 DI 10.1063/1.1149269 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900044 ER PT J AU de Kock, L Walker, C Coccorese, E Costley, AE Dremin, M Gernhardt, J Kasai, S Senda, I Shoji, T Leuer, J Snider, R McCarthy, P Portone, A Stott, P Young, K AF de Kock, L Walker, C Coccorese, E Costley, AE Dremin, M Gernhardt, J Kasai, S Senda, I Shoji, T Leuer, J Snider, R McCarthy, P Portone, A Stott, P Young, K TI Design of the magnetic diagnostic for ITER SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NJ SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB The detailed design of the magnetic diagnostic for ITER is presented. The system consists of groups of pickup coils and flux loops on the vessel wall, the back plate, and the divertor. These sensors provide the measurements for the equilibrium reconstruction and the fluctuation analysis. The system is supplemented by Rogowski coils for halo current measurements and by a diamagnetic loop. The complete system meets the measurement requirements, matching those of contemporary large divertor tokamaks. The maximum radiation exposure is such that the sensors will survive for the lifetime of the ITER. (C) 1999 American Institute of Physics. [S0034-6748(99)63201- 4]. C1 ITER, Joint Work Site, Garching, Germany. CREATE, Naples, Italy. ITER JWS, San Diego, CA USA. Kurchatov Inst, Moscow, Russia. Inst Plasmaphys, Garching, Germany. Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. Gen Atom Co, San Diego, CA USA. Univ Cork, Cork, Ireland. ITER JWS, Ibaraki, Osaka, Japan. Joint European Torus, Abingdon, Oxon, England. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP ITER, Joint Work Site, Garching, Germany. NR 7 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0034-6748 EI 1089-7623 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 452 EP 457 DI 10.1063/1.1149390 PN 2 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900052 ER PT J AU Young, KM AF Young, KM CA US Home Team TI A summary of the US contribution to ITER diagnostics design and research and development during the engineering design activity (abstract) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Meeting Abstract C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Young, KM (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 459 EP 459 DI 10.1063/1.1149510 PN 2 PG 1 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900054 ER PT J AU Nash, TJ Derzon, MS Chandler, GA Fehl, D Leeper, R Hurst, M Jobe, D Torres, J Seaman, J Lazier, S Gilliland, T McGurn, J AF Nash, TJ Derzon, MS Chandler, GA Fehl, D Leeper, R Hurst, M Jobe, D Torres, J Seaman, J Lazier, S Gilliland, T McGurn, J TI Axial diagnostic package for Z SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID FUSION AB We have developed and fielded an axial diagnostic package for the 20 MA, 100 ns, z- pinch driver Z. The package is used to diagnose dynamic hohlraum experiments which require an axial line of sight. The heart of the package is a reentrant cone originally used to diagnose ion-beam-driven hohlraums on PBFA-II. It has one diagnostic line of sight at 0 degrees, two at 4 degrees, four at 6 degrees, and four at 9 degrees. In addition it has a number of viewing, alignment, and vacuum feedthrough ports. The front of the package sits approximately 1.5 m from the pinch. This allows much closer proximity to the pinch, with inherently better resolution and signal, than is presently possible in viewing the pinch from the side. Debris that is preferentially directed along the axis is mitigated by two apertures for each line of sight, and by fast valves and imaging pinholes or cross slits for each diagnostic. In the initial run with this package we fielded a time-resolved pinhole camera, a five-channel pinhole-apertured x-ray diode array, a bolometer, a spatially resolved time-integrated crystal spectrometer, and a spatially and temporally resolved crystal spectrometer. We will present data obtained from these diagnostics in the dynamic hohlraum research conducted on Z. (C) 1999 American Institute of Physics. [S0034-6748(99)54801-6]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Nash, TJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 14 Z9 14 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 464 EP 467 DI 10.1063/1.1149308 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900056 ER PT J AU Hurst, MJ Nash, TJ Derzon, M Kellogg, JW Torres, J McGurn, J Seaman, J Jobe, D Lazier, SE AF Hurst, MJ Nash, TJ Derzon, M Kellogg, JW Torres, J McGurn, J Seaman, J Jobe, D Lazier, SE TI Fielding of the on-axis diagnostic package at Z SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB We have developed a comprehensive diagnostic package for observing z-pinch radiation along the pinch axis on the Z accelerator. The instrumentation, fielded on the axial package, are x-ray diagnostics requiring direct lines of sight to the target. The diagnostics require vacuum access to the center of the accelerator. The environment is a hostile one, where we must deal with an intense, energetic photon flux (> 100 keV) debris (e. g., bullets or shrapnel), and mechanical shock in order for the diagnostics to survive. In addition, practical constraints require the package be refurbished and utilized on a once a day shot schedule. In spite of this harsh environment, we have successfully fielded the diagnostic package with a high survivability of the data and the instruments. In this article, we describe the environment and issues related to the reentrant diagnostic package's implementation and maintenance. (C) 1999 American Institute of Physics. [S0034-6748(99)61601- X]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. K Tech Corp, Albuquerque, NM USA. RP Hurst, MJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 468 EP 470 DI 10.1063/1.1149377 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900057 ER PT J AU Barnes, CW Tubbs, DL Beck, JB Hoffman, NM Klare, KA Oertel, JA Watt, RG Boehly, TR Bradley, DK Knauer, JP AF Barnes, CW Tubbs, DL Beck, JB Hoffman, NM Klare, KA Oertel, JA Watt, RG Boehly, TR Bradley, DK Knauer, JP TI Experimental configuration of direct drive cylindrical implosions on the OMEGA laser SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID INSTABILITY AB Details about the cylindrical implosions using direct-drive irradiation on the OMEGA Laser facility are provided. The experimental configuration, including orientation, construction, and mounting of the targets is described. An attempt to characterize the modulation transfer function of the primary x-ray framing camera diagnostic results in insufficient exposure contrast but relative agreement with other determinations. The x-ray intensity of the titanium backlighter driven by the 2.5-ns-linear ramp of the laser beams is described, and the relative intensity on film is compared to similar Nova experiments. The parallax effects of different length marker layers of high-opacity dichloropolystyrene are measured, resulting in the conclusion that the marker layer length should be matched to the laser drive illumination profile. (C) 1999 American Institute of Physics. [S0034-6748(99)73501-X]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. RP Barnes, CW (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 9 TC 12 Z9 12 U1 2 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 471 EP 475 DI 10.1063/1.1149480 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900058 ER PT J AU Kaita, R Hatcher, R Johnson, D Kugel, H McCormack, B Roquemore, AL AF Kaita, R Hatcher, R Johnson, D Kugel, H McCormack, B Roquemore, AL CA NSTX Team TI Diagnostics for initial plasma operations on the National Spherical Torus Experiment SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID TOKAMAKS; EMISSION AB The goals of the diagnostic set for initial plasma operations on the National Spherical Torus Experiment (NSTX) are to provide information on the fundamental discharge parameters necessary to characterize NSTX plasmas, and guide NSTX operations for optimized performance. While most of these diagnostics involve relatively straightforward techniques requiring little or no research and development, and rely heavily on reusing existing equipment, a few pose considerable challenges due to the NSTX geometry. Magnetic diagnostics and visible discharge imaging will be the primary systems for plasma control and equilibrium. Confinement and transport studies will be supported by electron temperature, density, and impurity profile diagnostics. Scrapeoff layer and divertor physics will be investigated with spectroscopic and bolometric diagnostics, thermocouples, and edge Langmuir probes. X-ray fluctuation diagnostics and magnetic pickup coils will be provided for MHD stability analysis. The latter impose special difficulties for NSTX, because of the high temperature environment and the very limited space on the center stack. This article provides an overview of the diagnostics planned for the first phase of NSTX, and highlights the design features needed to satisfy the difficult constraints the device imposes on magnetic diagnostics. (C) 1999 American Institute of Physics. [S0034-6748(99)52301- 0]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kaita, R (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 10 TC 1 Z9 1 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 480 EP 483 DI 10.1063/1.1149484 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900060 ER PT J AU Kugel, HW Gorman, J Kaita, R Munsat, T Stutman, D AF Kugel, HW Gorman, J Kaita, R Munsat, T Stutman, D TI Low velocity boron micro-pellet injector for edge and core impurity transport measurements SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB A simple low velocity boron micro-pellet injector has been under development for Current Drive Experiment Upgrade (CDX-U) spherical torus edge and core impurity transport measurements, and wall conditioning. The injector consists of 16 barrels on a rotatable turret. Each barrel can be loaded with boron powder particles of diameters ranging from 1 to 40 mu m diameter in amounts ranging from less than 0.25 mg to more than 2 mg. A selected barrel is manually rotated into firing position using a vacuum precision rotary/linear motion feedthrough. A piezoelectric valve gas feed system triggered by CDX-U discharge timing is used to control H-2 or D-2 propellant gas at a cylinder pressure of 5.8 x 10(-3) Pa (40 psi) or less. The injector barrel-to-CDX-U plasma edge distance is 0.47 m. Initial low mass injections of neutral boron beams were performed into CDX-U plasmas at a velocity of 23 m/s. Measurements were obtained with a filtered gated charge coupled device TV camera, bolometry, visible spectroscopy, and ultrasoft x-ray diagnostics. This work is in support of the present CDX-U research program and possible applications on National Spherical Torus Experiment. (C) 1999 American Institute of Physics. [S0034-6748(99)52501-X]. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Kugel, HW (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Stutman, Dan/P-4048-2015 NR 9 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 493 EP 497 DI 10.1063/1.1149486 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900063 ER PT J AU Koch, JA Landen, OL Hammel, BA Brown, C Seely, J Aglitskiy, Y AF Koch, JA Landen, OL Hammel, BA Brown, C Seely, J Aglitskiy, Y TI Recent progress in high-energy, high-resolution x-ray imaging techniques for application to the National Ignition Facility (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID LASER; FUSION; NOVA; GAIN AB Multi-keV x-ray microscopy will be an important laser-produced plasma diagnostic at future megajoule facilities such as the National Ignition Facility (NIF). However, laser energies and plasma characteristics imply that x-ray microscopy will be more challenging at NIF than at existing facilities. In earlier work, we concluded that target-mounted pinholes and single spherical or toroidal crystals are good options for many x-ray microscopy applications at NIF. In this article, we review the experimental progress we have made investigating these systems on the Nova and Petawatt Laser Facilities. In particular, we have performed high-resolution, high-magnification target-mounted pinhole imaging of Nova implosions, and we have obtained promising preliminary spherical-crystal data from high-intensity Petawatt experiments. We are also designing a high-energy spherical-crystal imager for use on Nova experiments. (C) 1999 American Institute of Physics. [S0034-6748(99)57501-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Washington, DC 20375 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Koch, JA (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-021, Livermore, CA 94550 USA. NR 16 TC 16 Z9 18 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 525 EP 529 DI 10.1063/1.1149271 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900071 ER PT J AU Glendinning, SG Amendt, P Cline, BD Ehrlich, RB Hammel, BA Kalantar, DH Landen, OL Turner, RE Wallace, RJ Weiland, TJ Dague, N Jadaud, JP Bradley, DK Pien, G Morse, S AF Glendinning, SG Amendt, P Cline, BD Ehrlich, RB Hammel, BA Kalantar, DH Landen, OL Turner, RE Wallace, RJ Weiland, TJ Dague, N Jadaud, JP Bradley, DK Pien, G Morse, S TI Hohlraum symmetry measurements with surrogate solid targets (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID NOVA; IGNITION; FUSION AB Time-resolved radiographic imaging of low density, solid spherical surrogate targets has been used to provide a time-dependent measurement of drive pressure symmetry in cylindrical hohlraums on both the Nova and Omega lasers. The experiments replace the usual capsule at the center of a gold hohlraum with a sphere of SiO2 foam (rho=0.3 g/cm(3)). The laser generates an x-ray drive inside the hohlraum which does not produce perfectly symmetric drive pressure on a spherical target, giving rise to a distorted shock traveling radially inward. The rarefaction behind the shock generated in this sphere produces a rapid rise in x-ray transmission which is easily detectable experimentally by radiography. The position of this feature may be determined to within a few microns in our experimental setup using a gated x-ray pinhole camera. Time-dependent control of drive symmetry in a hohlraum requires the ability to adjust the laser power as a function of both time and position along the hohlraum axis. We have implemented this control on the Omega laser by delaying sets of beams ("beam staggering'') and on the Nova laser ("beam phasing'') by delivering two independent pulse shapes on inner and outer halves of the Nova beams. The improvement in P-2 pressure symmetry with this control as measured with the foam ball technique was found to be as much as a factor of 3, compared with deliberately mistuned drives. On the National Ignition Facility (NIF), we expect to use this technique as part of the effort to tune drive symmetry to achieve higher gain. We present results from these experiments from both facilities and comparisons with LASNEX simulations. In addition, we discuss the application of the foam ball technique to NIF targets. (C) 1999 American Institute of Physics. [S0034-6748(99)68901-8]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Ctr Etud Bruyeres Le Chatel, Direct Rech Ile De France, F-91680 Bruyeres Le Chatel, France. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. RP Glendinning, SG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 14 TC 16 Z9 19 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 536 EP 542 DI 10.1063/1.1149358 PN 2 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900073 ER PT J AU Kodama, R Takahashi, K Tanaka, KA Kato, Y Murai, K Weber, F Barbee, TW DaSilva, LB AF Kodama, R Takahashi, K Tanaka, KA Kato, Y Murai, K Weber, F Barbee, TW DaSilva, LB TI Measurements of laser-hole boring into overdense plasmas using x-ray laser refractometry (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID FILAMENTATION AB We developed a 19.6 nm laser x-ray laser grid-image refractometer (XRL-GIR) to diagnose laser-hole boring into overdense plasmas. The XRL-GIR was optimized to measure two-dimensional electron density perturbation on a scale of a few tens of mu m in underdense plasmas. Electron density profiles of laser-produced plasmas were obtained for 10(20)-10(22) cm(-3) with the XRL-GIR and for 10(19)-10(20) cm(-3) from an ultraviolet interferometer, the profiles of which were compared with those from hydrodynamic simulation. By using this XRL-GIR, we directly observed laser channeling into overdense plasmas accompanied by a bow shock wave showing a Mach cone ascribed to supersonic propagation of the channel front. (C) 1999 American Institute of Physics. [S0034-6748(99)61901-3]. C1 Osaka Univ, Inst Laser Engn, Suita, Osaka 565, Japan. Osaka Natl Res Inst, DMP, Ikeda, Osaka 563, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kodama, R (reprint author), Osaka Univ, Inst Laser Engn, Suita, Osaka 565, Japan. RI Kodama, Ryosuke/G-2627-2016 NR 17 TC 10 Z9 10 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 543 EP 548 DI 10.1063/1.1149380 PN 2 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900074 ER PT J AU Rochau, GA Derzon, MS Fehl, D Rochau, GE Lazier, S Droemer, D AF Rochau, GA Derzon, MS Fehl, D Rochau, GE Lazier, S Droemer, D TI Modeling a one-dimensional bremsstrahlung and neutron imaging array for use on Sandia's Z machine SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB Inertial confinement fusion is being studied on the Z facility at Sandia National Laboratories. Z is a large z-pinch machine which can provide 20 MA of current to z-pinch loads producing similar to 1.8 MJ of soft x rays in less than 10 ns. Within the pinch region, decelerated electrons produce a strong source of bremsstrahlung radiation which varies from shot to shot. Additionally, a variety of inertial confinement fusion targets may produce fusion neutrons, the intensity and distribution of which depend on the temperature and density of the pinch. In this article, we describe the computer modeling behind the shielding design of a simple time-resolved, one-dimensional imaging array. This diagnostic will provide a time history for both the bremsstrahlung and neutron production as a function of height in the target. Calculations show that by building an array of scintillator fibers separated by long, thin tungsten collimator plates, a sampling rate of 0.254 mm at the target can be achieved. The corresponding channel-to-channel discrimination for such a design is shown to be better than 1000::1 for <4 MeV photons and 100::1 for 2.45 MeV neutrons. By coupling scintillator fibers to a fiber-optic streak camera system, the system time response is expected to be dominated by the scintillator response (similar to 1.2 ns). (C) 1999 American Institute of Physics. [S0034-6748(99)55101-0]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Ktech Corp, Albuquerque, NM 87110 USA. Bechtel Nevada, Las Vegas, NV 89193 USA. RP Rochau, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 549 EP 552 DI 10.1063/1.1149284 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900075 ER PT J AU Rochau, GE Derzon, M Fehl, D Rochau, GA Sweeney, MA Tabor, D Lazier, SE Droemer, D Helvin, T Starbird, R AF Rochau, GE Derzon, M Fehl, D Rochau, GA Sweeney, MA Tabor, D Lazier, SE Droemer, D Helvin, T Starbird, R TI Measurement of the photon field, E > 150 eV on Sandia's Z Facility SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB The Z Facility at Sandia National Laboratories utilizes z-pinch implosions to produce up to 2 MJ of x rays. On Z, bremsstrahlung radiation is produced in various parts of the machine as a product of both power flow electrons and those accelerated in the pinch region. An understanding of the energy spectra and intensity of this radiation is important to both the explanation of the z-pinch physics and the design of new diagnostics. A technique has been developed using a differential absorption spectrometer to measure the photon field for energies greater that 150 eV for bremsstrahlung from the z-pinch or the vacuum transmission lines. This article describes the techniques and results used to date. (C) 1999 American Institute of Physics. [S0034-6748(99)74701-5]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. KTech Corp, Albuquerque, NM 87185 USA. Bechtel Nevada, Las Vegas, NV 89193 USA. RP Rochau, GE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 7 Z9 7 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 553 EP 556 DI 10.1063/1.1149353 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900076 ER PT J AU Chrien, RE Matuska, W Idzorek, G Swenson, FJ Peterson, DL Wilde, BH Porter, JL Breeze, SP Ruggles, LE Simpson, WW Vargas, M AF Chrien, RE Matuska, W Idzorek, G Swenson, FJ Peterson, DL Wilde, BH Porter, JL Breeze, SP Ruggles, LE Simpson, WW Vargas, M TI Measurement and simulation of apertures on Z hohlraums SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB We have performed aperture measurements and simulations for vacuum hohlraums heated by wire array implosions. A low-Z plastic coating is often applied to the aperture to create a high ablation pressure which retards the expansion of the gold hohlraum wall. However this interface is unstable and may be subject to the development of highly nonlinear perturbations ("jets") as a result of shocks converging near the edge of the aperture. These experiments have been simulated using Lagrangian and Eulerian radiation hydrodynamics codes. (C) 1999 American Institute of Physics. [S0034-6748(99)57601-6]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chrien, RE (reprint author), Univ Calif Los Alamos Natl Lab, MS E526, Los Alamos, NM 87545 USA. NR 4 TC 9 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 557 EP 560 DI 10.1063/1.1149354 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900077 ER PT J AU Chandler, GA Deeney, C Cuneo, M Fehl, DL McGurn, JS Spielman, RB Torres, JA McKenney, JL Mills, J Struve, KW AF Chandler, GA Deeney, C Cuneo, M Fehl, DL McGurn, JS Spielman, RB Torres, JA McKenney, JL Mills, J Struve, KW TI Filtered x-ray diode diagnostics fielded on the Z accelerator for source power measurements SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID Z-PINCH AB Filtered x-ray diode (XRD) detectors are used as primary radiation flux diagnostics on Sandia's Z accelerator, which generates nominally a 200-TW, 2-MJ, x-ray pulse. Given such flux levels and XRD sensitivities the detectors are being fielded 23 m from the source. The standard diagnostic setup and sensitivities are discussed. Vitreous carbon photocathodes are being used to reduce the effect of hydrocarbon contamination present in the Z-machine vacuum system. Nevertheless pre- and postcalibration data taken indicate spectrally dependent changes in the sensitivity of these detectors by up to factors of 2 or 3. (C) 1999 American Institute of Physics. [S0034-6748(99)70401-6]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. KTECH Corp, Albuquerque, NM USA. Mission Res Corp, Albuquerque, NM 87106 USA. RP Chandler, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 71 Z9 77 U1 0 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 561 EP 565 DI 10.1063/1.1149355 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900078 ER PT J AU Derzon, M Nash, T Chandler, G Cooper, G Fehl, D Hall, C Lash, J Leeper, R McGuire, E Mock, R Olsen, R Olson, C Rochau, GE Rochau, GA Ruiz, C Seamen, J Slutz, S Stygar, W Sweeney, MA Lazier, S Droemer, D Helvin, T Starbird, R AF Derzon, M Nash, T Chandler, G Cooper, G Fehl, D Hall, C Lash, J Leeper, R McGuire, E Mock, R Olsen, R Olson, C Rochau, GE Rochau, GA Ruiz, C Seamen, J Slutz, S Stygar, W Sweeney, MA Lazier, S Droemer, D Helvin, T Starbird, R TI Implications of high-energy photons and electrons on target preheat at the Sandia "Z" facility SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID RAY AB High-energy photons and electrons on the Sandia National Laboratories "Z" accelerator, a z-pinch device, will deposit energy into a capsule and fuel; this may create a potential preheat problem for inertial confinement infusion (ICF). In this article we discuss heating of the capsule and fuel by high-energy photons and electrons. The fuel is heated to <2 eV, in a time-integrated sense, on Z by these particles. Because peak implosion occurs at the peak in the soft x-ray emission on Z, the heating at times of interest is reduced roughly an order of magnitude to similar to 0.2 eV for times of interest and fuel preheat from this mechanism is concluded to be small. These estimates are generated from time-integrated bremsstrahlung measurements. The uncertainty in the heating is high because the electron spectrum is not known directly, but inferred. In addition, the influence of photons and electrons at energies between 5 and 60 keV is not known. Given the uncertainties at this point, we do not know the impact on the feasibility of internal dynamic hohlraums for a z-pinch-driven ICF implosion. We discuss these issues and suggest directions for further study. (C) 1999 American Institute of Physics. [S0034-6748(99)66501-7]. C1 Sandia Natl Labs, Albuquerque, NM 87112 USA. K Tech, Albuquerque, NM USA. Bechtel Nevada, Las Vegas, NV USA. RP Derzon, M (reprint author), Sandia Natl Labs, Albuquerque, NM 87112 USA. NR 6 TC 8 Z9 8 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 566 EP 568 DI 10.1063/1.1149445 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900079 ER PT J AU Stutman, D Finkenthal, M Soukhanovskii, V May, MJ Moos, HW Kaita, R AF Stutman, D Finkenthal, M Soukhanovskii, V May, MJ Moos, HW Kaita, R TI Ultrasoft x-ray imaging system for the National Spherical Torus Experiment SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID TOKAMAK AB A spectrally resolved ultrasoft x-ray imaging system, consisting of arrays of high resolution (<2 Angstrom) and throughput (greater than or equal to tens of kHz) miniature monochromators, and based on multilayer mirrors and absolute photodiodes, is being designed for the National Spherical Torus Experiment. Initially, three poloidal arrays of diodes filtered for C 1s-np emission will be implemented for fast tomographic imaging of the colder start-up plasmas. Later on, mirrors tuned to the C Ly(alpha) emission will be added in order to enable the arrays to "see" the periphery through the hot core and to study magnetohydrodynamic activity and impurity transport in this region. We also discuss possible core diagnostics, based on tomographic imaging of the Ly(alpha) emission from the plume of recombined, low Z impurity ions left by neutral beams or fueling pellets. The arrays can also be used for radiated power measurements and to map the distribution of high Z impurities injected for transport studies. The performance of the proposed system is illustrated with results from test channels on the CDX-U spherical torus at Princeton Plasma Physics Laboratory. (C) 1999 American Institute of Physics. [S0034-6748(99)57701-0]. C1 Johns Hopkins Univ, Baltimore, MD 21218 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Stutman, D (reprint author), Johns Hopkins Univ, Baltimore, MD 21218 USA. RI Stutman, Dan/P-4048-2015 NR 13 TC 31 Z9 31 U1 2 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 572 EP 576 DI 10.1063/1.1149272 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900081 ER PT J AU von Goeler, S Kaita, R Bitter, M Fuchs, G Poier, M Bertschinger, G Koslowski, HR Toi, K Ohdachi, S Donne, A AF von Goeler, S Kaita, R Bitter, M Fuchs, G Poier, M Bertschinger, G Koslowski, HR Toi, K Ohdachi, S Donne, A TI High speed tangential soft x-ray camera for the study of magnetohydrodynamics instabilities SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NJ SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID CURRENT-DENSITY MEASUREMENTS; TOKAMAK AB A fast camera system is being prepared for the TEXTOR tokamak for the investigation of magnetohydrodynamics (MHD) instabilities. The camera will consist of a scintillator screen for conversion of x rays into visible light, a fiberoptic cable for transport of the visible images out of the Textor magnetic field, an electrostatic image converter for amplification and demagnification of the images, and a fast charge-coupled device (CCD) camera for capturing and storing the image data. The purpose of our camera is two-dimensional imaging of magnetic islands and the structure of MHD instabilities. In order to increase the signal intensity and simultaneously reduce statistical noise, we maximize the diameter of the scintillator screen to 100 mm. For good time response, we use fast scintillators and phosphors, and plan to employ a 1 MHz framing CCD camera. MHD events having an amplitude larger than 1% can be observed with a time resolution of 100 kHz and a spatial resolution of 3 cm. In the future, the camera will be used on the Large Helical Device in Japan. (C) 1999 American Institute of Physics. [S0034-6748(99)62201-8]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Forschungszentrum Julich, Assoc Euratom KFA, Inst Plasmaphys, D-52425 Julich, Germany. Trilateral Euregio Cluster, D-52425 Julich, Germany. Natl Inst Fus Sci, Toki 50952, Japan. EURATOM, FOM, Inst Plasmafys Rijnhuizen, NL-3430 BE Nieuwegein, Netherlands. RP Princeton Plasma Phys Lab, Box 451, Princeton, NJ 08543 USA. NR 12 TC 23 Z9 23 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0034-6748 EI 1089-7623 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 599 EP 602 DI 10.1063/1.1149382 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900087 ER PT J AU Bennett, GR AF Bennett, GR TI Advanced one-dimensional x-ray microscope for the Omega Laser Facility SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SCATTERING; MIRRORS AB An analytical study of the on-axis aperture defect (spherical aberration) convolved with diffraction, for a simple spheric-based Kirkpatrick-Baez (KB) grazing incidence x-ray microscope, indicates the optimum performance is achieved by using a short object plane to mirror distances, steep grazing angles, and high x-ray energies. Other aberrations occur for off-axis field points, but if the spherical aberration can be reduced significantly the image improvement of an extended object should be dramatic. In the quest for ultrahigh x-ray spatial resolution, the Los Alamos one-dimensional (1D) KB (at the time of writing, under fabrication) fully exploits these facts in a 40 mm working distance, steep grazing angle multilayer mirror, 4.316 keV design. A rigorous analysis of Zernike surface deformations, and all other fabrication/assembly errors indicates negligible image degradation of the predicted very high resolution performance; a similar study of existing KBs closely models the 3-5 mu m resolutions over the relevant field sizes. In addition, a novel analytical and ray trace optimization technique allows larger working distances at even higher resolutions. Due to instrument length constraints, however, this approach was not incorporated into the 4.316 keV 1DKB; although, in the future such designs could be easily accommodated on The National Ignition Facility. (C) 1999 American Institute of Physics. [S0034-6748(99)69001-3]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bennett, GR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS E526, Los Alamos, NM 87545 USA. NR 8 TC 6 Z9 10 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 608 EP 612 DI 10.1063/1.1149433 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900089 ER PT J AU Workman, J Tierney, T Evans, S Kyrala, G Benage, J AF Workman, J Tierney, T Evans, S Kyrala, G Benage, J TI One-dimensional x-ray microscope for shock measurements in high-density aluminum plasmas SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID BENT CRYSTALS; LASER; SPECTROSCOPY AB Accurate experimental measurements of the equation of state for strongly coupled plasmas (Gamma greater than or equal to 1), relevant to astrophysical, geologic and inertial confinement fusion applications, have been extremely difficult. In this pursuit, we have designed a one-dimensional dual-crystal x-ray microscope for making high-resolution measurements of shocks launched by laser pulses in high-density aluminum plasmas. Optical ray-tracing analysis of the design is presented including effects of surface aberrations. The spherically bent mica crystals are arranged at near normal incidence to operate at energies of 1.35 and 4.75 keV using the second and seventh order reflections, respectively. With a magnification of 45X, the microscope's spatial resolution is predicted to be better than 2 mu m when coupled to an x-ray streak camera. The addition of a grazing-incidence optic perpendicular to the imaging direction partially compensates astigmatism. This compensation provides an increase in collection efficiency at the streak camera slit by a factor of similar to 15. (C) 1999 American Institute of Physics.[S0034-6748(99)62401-7]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Workman, J (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 14 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 613 EP 616 DI 10.1063/1.1149359 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900090 ER PT J AU Marshall, FJ Bennett, GR AF Marshall, FJ Bennett, GR TI A high-energy x-ray microscope for inertial confinement fusion SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB We have developed a microscope capable of imaging x-ray emission from inertial confinement fusion targets in the range of 7-9 keV. Imaging is accomplished with a Kirkpatrick-Baez type, four-image microscope coated with a WB4C multilayer having a 2d period of 140 Angstrom. This microscope design (a standard used on the University of Rochester's OMEGA laser system) is capable of 5 mu m resolution over a region large enough to image an imploded target (similar to 400 mu m). This design is capable of being extended to similar to 40 keV if state-of-the-art, short-spacing, multilayer coatings are used (similar to 25 Angstrom), and has been configured to obtain 3 mu m resolution with the appropriate choice of mirror size. As such, this type of microscope could serve as a platform for multiframe, hard x-ray imaging on the National Ignition Facility. Characterization of the microscope and laboratory measurements of the energy response made with a cw x-ray source will be shown. (C) 1999 American Institute of Physics. [S0034-6748(99)50501-7]. C1 Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Marshall, FJ (reprint author), Univ Rochester, Laser Energet Lab, 250 E River Rd, Rochester, NY 14623 USA. NR 12 TC 23 Z9 32 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 617 EP 619 DI 10.1063/1.1149312 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900091 ER PT J AU Kalantar, DH Chandler, EA Colvin, JD Lee, R Remington, BA Weber, SV Hauer, A Wark, JS Loveridge, A Failor, BH Meyers, MA Ravichandran, G Wiley, LG AF Kalantar, DH Chandler, EA Colvin, JD Lee, R Remington, BA Weber, SV Hauer, A Wark, JS Loveridge, A Failor, BH Meyers, MA Ravichandran, G Wiley, LG TI Transient x-ray diffraction used to diagnose shock compressed Si crystals on the Nova laser SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB Transient x-ray diffraction is used to record time-resolved information about the shock compression of materials. This technique has been applied on Nova shock experiments driven using a hohlraum x-ray drive. Data were recorded from the shock release at the free surface of a Si crystal, as well as from Si at an embedded ablator/Si interface. Modeling has been done to simulate the diffraction data incorporating the strained crystal rocking curves and Bragg diffraction efficiencies. Examples of the data and post-processed simulations are presented. (C) 1999 American Institute of Physics. [S0034-6748(99)62601-6]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Phys Int Co, San Leandro, CA 94577 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. CALTECH, Pasadena, CA 91125 USA. RP Kalantar, DH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Meyers, Marc/A-2970-2016 OI Meyers, Marc/0000-0003-1698-5396 NR 12 TC 23 Z9 25 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 629 EP 632 DI 10.1063/1.1149384 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900095 ER PT J AU Ruggles, LE Porter, JL Simpson, WW Vargas, MF AF Ruggles, LE Porter, JL Simpson, WW Vargas, MF TI Sensitivity measurements of a microchannel plate intensified x-ray detector in the 100-1500 eV photon energy range (abstract) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Meeting Abstract C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ruggles, LE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 646 EP 646 DI 10.1063/1.1149525 PN 2 PG 1 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900100 ER PT J AU Spielman, RB Deeney, C Fehl, DL Hanson, DL Keltner, NR McGum, JS McKenney, JL AF Spielman, RB Deeney, C Fehl, DL Hanson, DL Keltner, NR McGum, JS McKenney, JL TI Fast resistive bolometry SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB Resistive bolometry is an accurate, robust, spectrally broadband technique for measuring absolute x-ray fluence and flux. Bolometry is an independent technique for x-ray measurements that is based on a different set of physical properties than other diagnostics such as x-ray diodes, photoconducting detectors, and P-I-N diodes. Bolometers use the temperature-driven change in element resistivity to determine the total deposited energy. The calibration of such a device is based on fundamental material properties and its physical dimensions. We describe the use of nickel and gold bolometers to measure x rays generated by high-power z pinches on Sandia's Saturn and Z accelerators. The Sandia bolometer design described herein has a pulse response of similar to 1 ns. We describe in detail the fabrication, fielding, and data analysis issues leading to highly accurate x-ray measurements. The fundamental accuracy of resistive bolometry will be discussed. (C) 1999 American Institute of Physics. [S0034-6748(99)52701-9]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Spielman, RB (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 58 Z9 64 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 651 EP 655 DI 10.1063/1.1149488 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900102 ER PT J AU Turner, RE Landen, OL Bell, P Costa, R Hargrove, D AF Turner, RE Landen, OL Bell, P Costa, R Hargrove, D TI Achromatically filtered diamond photoconductive detectors for high power soft x-ray flux measurements SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID LASER AB A 1-mm-square diamond photoconductive detector (PCD) has been installed on the LLNL Nova laser system, for use as a broadband soft x-ray power diagnostic. The PCD is installed behind an array of pinholes, which cast multiple, overlapping images of the source onto the diamond. This allows reduction of the x-ray intensity, to avoid saturation problems, while avoiding the spectral dependency of thin film filters. The diode current is read out on a 5 GHz bandwidth scope. The system is calibrated by comparison to an absolutely calibrated array of filtered vacuum x-ray photodiodes ("dante''). The time response of the PCD and its bias electronics have been characterized using the 5th harmonic (210 nm) of a short pulse (< 1 ps) Ti: sapphire laser. The data show a fast rise, limited by the 5 GHz scope bandwidth, and a slower fall off, characterized by an RC time of order 200 ps. (C) 1999 American Institute of Physics. [S0034-6748(99)62701-0]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Turner, RE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 10 TC 27 Z9 29 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 656 EP 658 DI 10.1063/1.1149385 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900103 ER PT J AU Ze, F Landen, OL Bell, PM Turner, RE Tutt, T Alvarez, SS Costa, RL AF Ze, F Landen, OL Bell, PM Turner, RE Tutt, T Alvarez, SS Costa, RL TI Investigation of quantum efficiencies in multilayered photocathodes for microchannel plate applications SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB Microchannel plates (MCPs) are used in many diagnostic systems to study laser-plasma interactions. Typically the front surface of a MCP is coated with some photocathode (PC) material to convert x ray to electron. This is followed by electron multiplication along the microchannels. Materials such as CsI, Al, and Au have been identified as good PC materials, but the overall quantum efficiencies of these materials are low, so that electron multiplication along the channel has been the only path to signal amplification. This approach is known to have some problems (J.D. Wiedwald, University of California UCRL-JC-110906, August 1992). We investigated the effect of pairing transmission PC to standard MC's and found that CsI and Au foils used in multilayered configuration, significantly enhance the overall quantum efficiency of the combination. The findings could lead to better MCP design and fabrication. [S0034-6748(99)60201-5]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ze, F (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 10 TC 4 Z9 4 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 659 EP 662 DI 10.1063/1.1149343 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900104 ER PT J AU Suter, LJ Landen, OL Koch, JI AF Suter, LJ Landen, OL Koch, JI TI Prospects for fluorescence based imaging/visualization of hydrodynamic systems on the National Ignition Facility SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID PLASMAS; LIGHT AB The next generation of large, high power lasers, such as the National Ignition Facility in the U.S., Laser Mega Joule in France or Helen Successor in the United Kingdom offers the prospect of x-ray fluorescence based diagnosis of hydrodynamic experiments. We discuss two promising techniques for pumping this fluorescence. One is to use a large fraction of these facilities' high power to efficiently make multi-kilovolt x rays which, in turn, causes dopants placed in experimental packages to fluoresce. The second technique is to use the sizable multi-kilovolt photon background that we expect to be present in many hohlraum based experiments, while the driving laser is on, to pump x-ray fluorescence. Here, the fluorescing medium could be a dopant in an experimental package or, possibly, a relatively thick slab of material in the hohlraum wall which could serve as a backlighter. (C) 1999 American Institute of Physics. [S0034-6748(99)63301-9]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Suter, LJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 12 TC 8 Z9 8 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 663 EP 666 DI 10.1063/1.1149391 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900105 ER PT J AU Moody, JD MacGowan, BJ Glenzer, SH Kirkwood, RK Kruer, WL Pollaine, SM Williams, EA Stone, GF Afeyan, BB Schmitt, AJ AF Moody, JD MacGowan, BJ Glenzer, SH Kirkwood, RK Kruer, WL Pollaine, SM Williams, EA Stone, GF Afeyan, BB Schmitt, AJ TI Measurements of near forward scattered laser light in a large inertial confinement fusion plasma (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID NOVA AB We describe an instrument which measures the angular spread and spectrum of near forward scattered laser light from a probe beam in a long scalelength laser plasma. The instrument consists of a combination of time integrating and time resolving detectors which measure the scattered light amplitude over four orders of magnitude for a range of angles. These measurements allow us to study the beam spray resulting from various laser and plasma conditions and determine the density fluctuations associated with this beam spray. (C) 1999 American Institute of Physics. [S0034-6748(99)62801-5]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Polymath Associates, Livermore, CA 94550 USA. USN, Res Lab, Washington, DC 20375 USA. RP Moody, JD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 7 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 677 EP 681 DI 10.1063/1.1149386 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900109 ER PT J AU Kyrala, GA Johnson, RP Hurry, T AF Kyrala, GA Johnson, RP Hurry, T TI A new interferometer to measure preheat in laser targets SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SHOCK-WAVE EXPERIMENTS; DRIVEN; PRESSURES; EQUATION; STATE; MBAR; TPA AB Many interferometer designs exist to measure the distance change through a fringe displacement. Different interferometers were used to measure the movement of the backside of a heated foil in laser plasma interactions. However, when a laser heated target sits in the middle of a target chamber with noise from pumps and other sources of vibrations, the fringes become difficult to observe and align. We have built a differential interferometer where the light paths in each arm of the interferometer retrace each other, hence making the fringes much less sensitive to vibrations than a regular interferometer. This allows the main part of the interferometer to sit outside the vacuum chamber, where it is easy to align. The final focusing element resides close to the target and collects a significant amount of the scattered light. In this investigation we will use the interferometer to measure the expansion of the backside of a preheated target in the TRIDENT chamber. Using the coefficient of linear expansion, the heat capacity of the material, and the expansion distance, we estimate a time dependent preheat temperature of the target. [S0034-6748(99)74801-X]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kyrala, GA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 682 EP 686 DI 10.1063/1.1149469 PN 2 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900110 ER PT J AU Park, HK Domier, CW Geck, WR Luhmann, NC AF Park, HK Domier, CW Geck, WR Luhmann, NC TI Far infrared tangential interferometry/polarimetry on the National Spherical Tokamak Experiment SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID FARADAY-ROTATION; SYSTEM AB Measurement of the core B-T(r,t) value is essential in the National Spherical Tokamak Experiment (NSTX), since the effects of paramagnetism and diamagnetism in the NSTX are expected to be considerably greater than that in higher aspect ratio tokamaks. Therefore, without independent B-T(r,t) measurement, plasma parameters dependent upon B-T such as the q profile and local beta value cannot be evaluated. Tangential interferometer/polarimeter systems (eight channels) [H. Park, L. Guttadora, C. Domier, W. R. Geck, and N. C. Luhman, Jr., First and Second NSTX Research Forums, Princeton, NJ, 1997 (unpublished)] for the NSTX will provide temporally and radially resolved toroidal field profile [B-T(r,t)] and two-dimensional electron density profile [n(e)(r,t)] data. The outcome of the proposed system is extremely important to the study of confinement, heating, and stability of the NSTX plasmas. The research task is largely based on utilizing existing hardware from the TFTR multichannel infrared interferometer system [D.K. Mansfield, H. K. Park, L. C. Johnson, H. Anderson, S. Foote, B. Clifton, and C. H. Ma, Appl. Opt. 26, 4469 (1987) and H. K. Park, D. K. Mansfield, and C. L. Johnson, Proceedings of the 3rd International Symposium on Laser-Aided Plasma Diagnostic, Los Angeles, CA, 28-30 Oct. 1987 (unpublished), pp. 96-104] which will be reconfigured into a tangential system for NSTX, and to develop the additional hardware required to complete the system. (C) 1999 American Institute of Physics. [S0034-6748(99)58101-X]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 95616 USA. RP Park, HK (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 10 TC 29 Z9 29 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 710 EP 713 DI 10.1063/1.1149364 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900118 ER PT J AU Maqueda, RJ Wurden, GA Terry, JL Stillerman, JA AF Maqueda, RJ Wurden, GA Terry, JL Stillerman, JA TI The new infrared imaging system on Alcator C-Mod SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB A new infrared imaging system has been installed on Alcator C-Mod. This system uses an Amber Radiance 1 IR video camera (filtered to the 4.2-4.4 mu m band) to view a 30 cmX30 cm region of the lower divertor from above by means of a re-entrant 5-m long ZnSe based periscope. Capture of the standard 30 Hz video frames (8-bit) and camera control are performed remotely over fiber optic links by a Windows 95 PC, using a MuTech MV-1000 video grabber board. Plans are under way to directly capture the 60 Hz, 12-bit, 256X256 pixel images using a digital video camera interface with a fiber optic link from EDT (Beaverton, Oregon). Preliminary results show that during nondisruptive discharges no substantial surface temperature increase is observed on the upper sections of the divertor, with the exception of "hot spots,'' although occasionally, increased heating in toroidal bands is seen. Bands can also be observed after disruptions that result in a downward movement of the plasma. (C) 1999 American Institute of Physics. [S0034-6748(99)53501-6]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RP Maqueda, RJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Wurden, Glen/A-1921-2017; OI Wurden, Glen/0000-0003-2991-1484; Stillerman, Joshua/0000-0003-0901-0806 NR 2 TC 10 Z9 10 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 734 EP 737 DI 10.1063/1.1149496 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900124 ER PT J AU Nilson, DG Fenstermacher, ME Ellis, R Brewis, G Jalufka, N Snider, RT AF Nilson, DG Fenstermacher, ME Ellis, R Brewis, G Jalufka, N Snider, RT TI A tangentially viewing vacuum ultraviolet TV system for the DIII-D divertor SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB A video camera system capable of imaging vacuum ultraviolet emission in the 120-160 nm wavelength range, from the entire divertor region in the DIII-D tokamak, was designed. The new system has a tangential view of the divertor similar to an existing tangential camera system [M. E. Fenstermacher et al., Rev. Sci. Instrum. 68, 974 (1997)] which has produced two-dimensional maps of visible line emission (400-800 nm) from deuterium and carbon in the divertor region. However, the overwhelming fraction of the power radiated by these elements is emitted by resonance transitions in the ultraviolet, namely the C IV line at 155.0 nm and Ly-alpha line at 121.6 nm. To image the ultraviolet light with an angular view including the inner wall and outer bias ring in DIII-D, a six-element optical system (f/8.9) was designed using a combination of reflective and refractive optics. This system will provide a spatial resolution of 1.2 cm in the object plane. An intermediate UV image formed in a secondary vacuum is converted to the visible by means of a phosphor plate and detected with a conventional charge injection device (CID) camera (30 ms framing rate). A single MgF2 lens serves as the vacuum interface between the primary and secondary vacuums; a second lens must be inserted in the secondary vacuum to correct the focus at 155 nm. Using the same tomographic inversion method employed for the visible TV, we will reconstruct the poloidal distribution of the UV divertor light. The grain size of the phosphor plate and the optical system aberrations limit the best focus spot size to 60 mu m at the CID plane. The optical system is designed to withstand 350 degrees C vessel bakeout, 2 T magnetic fields, and disruption-induced accelerations of the vessel. (C) 1999 American Institute of Physics. [S0034-6748(99)55301-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Allied Opt, Oceanside, CA 92056 USA. Hampton Univ, Ctr Fus Res & Training, Hampton, VA 23668 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Nilson, DG (reprint author), Gen Atom Co, San Diego, CA 92186 USA. NR 4 TC 12 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 738 EP 741 DI 10.1063/1.1149286 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900125 ER PT J AU Munsat, T LeBlanc, B AF Munsat, T LeBlanc, B TI A low-cost multichannel Thomson scattering system for CDX-U SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB A multichannel Thomson scattering system has been developed for the CDX-U spherical torus. The system is designed for 10 eV < T-e < 400 eV, n(e) <10(18) m(-3), which includes typical and predicted central and edge conditions in CDX-U. The system uses two laser passes to double the scattered photons from a 5 J ruby laser. The beam path is vertical through the similar to 66 cm (elongated) diameter of the plasma and is movable in the major-radial direction, enabling coverage of nearly 70% of the major-radial plasma extent. Twelve channels over the vertical minor radius provide similar to 2.5 cm spatial resolution. The main collecting lens, located 45 cm from the laser beamline, provides high solid angle (Delta Omega similar to 0.01) light collection using a 15 cm diam lens. The system makes maximum usage of an optically fast (f/1.8) compact imaging spectrometer. An intensified charge coupled device with a GaAs photocathode provides quantum efficiency of similar to 20% at 6943 Angstrom. The combination of plasma access, multiple beam passes, high-throughput spectrometer, and high quantum efficiency detector provide for very high total photon statistics in a relatively simple and inexpensive system. (C) 1999 American Institute of Physics. [S0034-6748(99)55401-4]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Munsat, T (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 5 Z9 5 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 755 EP 758 DI 10.1063/1.1149365 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900129 ER PT J AU Johnson, D Bretz, N LeBlanc, B Palladino, R Long, D Parsells, R AF Johnson, D Bretz, N LeBlanc, B Palladino, R Long, D Parsells, R TI Multipulse Thomson scattering system for the National Spherical Torus Experiment SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID TOKAMAK AB A design using a backscattering geometry is presented, which emphasizes high sensitivity and high spatial resolution at the outer edge of the National Spherical Torus Experiment, while providing full profile capability with a moderate number of channels. The design is based on Nd:YAG lasers and avalanche photodiode detectors to allow for high repetition rate measurements. (C) 1999 American Institute of Physics. [S0034-6748(99)58201-4]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Johnson, D (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 8 TC 25 Z9 25 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 776 EP 779 DI 10.1063/1.1149276 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900134 ER PT J AU Medley, SS AF Medley, SS TI Design study of a visible/infrared periscope for intense radiation applications using reflective optics SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab AB In magnetically confined fusion devices employing deuterium-tritium (D-T) operation, refractive optical components exposed to neutron and gamma radiation can be subject to degradation of the transmission characteristics, induced luminescence, and altered mechanical properties including dimensional changes. Although radiation resistant refractive optics functioned well for the Tokamak Fusion Test Reactor periscope system during D-T operation, this design approach is unpromising in the much more hostile radiation environment of future D-T devices such as International Thermonuclear Experimental Reactor (ITER). Under contract to the Princeton Plasma Physics Laboratory, Ball Aerospace of Colorado carried out a periscope design study based on the use of reflective optics. In this design, beryllium reflective input optics supported by a fused silica optical bench were interfaced to a Cassegrain relay system to transfer plasma images to remotely located cameras. This system is also capable of measuring first-wall surface temperatures in the range of 300-2000 degrees C even under projected heating of the reflective optics themselves to several hundred degrees Celsius. Tests of beryllium mirror samples, however, revealed that operation at temperatures above 700 degrees C leads to a loss of specular reflectivity, thus placing an upper limit on the acceptable thermal environment. The main results of this periscope study are presented in this article. (C) 1999 American Institute of Physics. [S0034-6748(99)73701-9]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Medley, SS (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 7 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 794 EP 797 DI 10.1063/1.1149459 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900139 ER PT J AU Oertel, JA Murphy, TJ Berggren, RR Faulkner, J Schmell, R Little, D Archuleta, T Lopez, J Velarde, J Horton, RF AF Oertel, JA Murphy, TJ Berggren, RR Faulkner, J Schmell, R Little, D Archuleta, T Lopez, J Velarde, J Horton, RF TI Multipurpose 10 inch manipulator-based optical telescope for Omega and the Trident laser facilities SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID DRIVEN AB We have recently designed and are building a telescope which acts as an imaging light collector relaying the image to an optical table for experiment dependent analysis and recording. The expected primary use of this instrument is a streaked optical pyrometer for witness plate measurements of the hohlraum drive temperature. The telescope is based on the University of Rochester's 10 in. manipulator (TIM) which allows compatibility between Omega, Trident, and the NIF lasers. The optics capture a f/7 cone of light, have a field of view of 6 mm, have a spatial resolution of 5-7 mu m per line pair at the object plane, and are optimized for operation at 280 nm. The image is at a magnification of 11.7X, which is convenient for many experiments, but can be changed using additional optics that reside outside the TIM. (C) 1999 American Institute of Physics. [S0034-6748(99)64501-4]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sci Applicat Int Corp, Albuquerque, NM 87106 USA. RP Oertel, JA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Murphy, Thomas/F-3101-2014 OI Murphy, Thomas/0000-0002-6137-9873 NR 6 TC 19 Z9 19 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 803 EP 805 DI 10.1063/1.1149403 PN 2 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900142 ER PT J AU Budil, KS Gold, DM Estabrook, KG Remington, BA Kane, J Bell, PM Pennington, D Brown, C Hatchett, S Koch, JA Key, MH Perry, MD AF Budil, KS Gold, DM Estabrook, KG Remington, BA Kane, J Bell, PM Pennington, D Brown, C Hatchett, S Koch, JA Key, MH Perry, MD TI Blast wave diagnostic for the Petawatt laser system SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID SHOCKS; INSTABILITY AB We report on a diagnostic to measure the trajectory of a blast wave propagating through a plastic target 400 mu m thick. This blast wave is generated by the irradiation of the front surface of the target with similar to 400 J of 1 mu m laser radiation in a 20 ps pulse focused to similar to 50 mu m diameter spot, which produces an intensity in excess of 10(18) W/cm(2). These conditions approximate a point explosion and a blast wave is predicted to be generated with an initial pressure nearing 1 Gbar which decays as it travels approximately radially outward from the interaction region. We have utilized streaked optical pyrometry of the blast front to determine its time of arrival at the rear surface of the target. Applications of a self-similar Taylor-Sedov blast wave solution allows the amount of energy deposited to be estimated. The experiment, LASNEX design simulations and initial results are discussed. (C) 1999 American Institute of Physics. [S0034-6748(99)58301-9]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Budil, KS (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-21, Livermore, CA 94550 USA. NR 21 TC 3 Z9 3 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 806 EP 809 DI 10.1063/1.1149277 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900143 ER PT J AU Rice, BW Nilson, DG Burrell, KH Lao, LL AF Rice, BW Nilson, DG Burrell, KH Lao, LL TI Simultaneous measurement of q and E-r profiles using the motional Stark effect in high-performance DIII-D plasmas (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID REVERSED MAGNETIC SHEAR; RADIAL ELECTRIC-FIELD; TOKAMAK; CONFINEMENT; POLARIMETRY; DISCHARGES; TRANSPORT AB The motional Stark effect (MSE) diagnostic was developed to provide a measurement of the magnetic pitch angle or q profile in tokamaks. The technique relies upon polarization measurements of Stark broadened D-alpha emission to determine the pitch angle of the Lorentz upsilon(b) X B electric field, where upsilon(b) is the injected neutral beam particle velocity and B is the total magnetic field. However, in many advanced confinement regimes, large values of the plasma radial electric field, E-r, are observed and can affect the interpretation of MSE measurements. Viewing fixed locations in the plasma from two different viewing angles allows one to separate the E-r field from the upsilon(b) X B field, thus providing simultaneous measurement of the E-r and q profiles. To achieve this measurement, the DIII-D MSE diagnostic was recently upgraded from 16 to 35 channels with three independent viewing angles. The new instrument provides an E-r resolution of 5-10 kV/m with a time response of 1 ms. Measurement results from the VH mode, reverse shear, and H mode plasmas are presented. (C) 1999 American Institute of Physics. [S0034-6748(99)51001-0]. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Rice, BW (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 16 TC 61 Z9 61 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 815 EP 820 DI 10.1063/1.1149317 PN 2 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900145 ER PT J AU Bell, RE Dudek, LE Grek, B Johnson, DW Palladino, RW AF Bell, RE Dudek, LE Grek, B Johnson, DW Palladino, RW TI Tokamak fusion test reactor poloidal rotation diagnostic (invited) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID PLASMAS; PROFILES AB A new spectroscopic diagnostic was developed to measure poloidal velocity profiles of Tokamak fusion test reactor (TFTR) plasmas. Carbon poloidal velocities were measured using the Doppler shift of the C VI 5291 Angstrom impurity line of both intrinsic emission and charge exchange emission from neutral beams. Poloidal velocities are typically small (upsilon(theta) less than or equal to 10(4) m/s) requiring small wavelength shifts (Delta lambda less than or equal to 0.2 Angstrom) to be measured. However, the high central ion temperatures in TFTR required the use of a low dispersion spectrometer to view the entire linewidth (full width at half maximum less than or equal to 25 Angstrom). A very high throughput spectrometer/ detector system was assembled to achieve the necessary precision in upsilon(theta) upsilon(theta). Statistical errors in the chord-averaged poloidal velocity less than 100 m/s have been obtained. The short focal length spectrometer features f/1.8 input optics, a transmission grating, and refractive optics. A thinned back-illuminated charge coupled device detector provided a high quantum efficiency (QE=75%). The diagnostic had 20 ms time resolution and a radial resolution of less than or equal to 3.5 cm after an inversion. Two symmetric up/down views were used to eliminate atomic physics effects that would otherwise distort the measured rotation velocity. This diagnostic complemented the measurements of T-i, upsilon(phi), and n(i) from a charge exchange spectroscopy system, allowing the determination of radial electric field profiles using the force balance equation. (C) 1999 American Institute of Physics. [S0034-6748(99)73801-3]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Bell, RE (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 17 TC 37 Z9 37 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 821 EP 826 DI 10.1063/1.1149460 PN 2 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900146 ER PT J AU Isobe, M Darrow, DS Kondo, T Sasao, M Toi, K Osakabe, M Shimizu, H Yoshimura, Y Takahashi, C Murakami, S Okamura, S Matsuoka, K AF Isobe, M Darrow, DS Kondo, T Sasao, M Toi, K Osakabe, M Shimizu, H Yoshimura, Y Takahashi, C Murakami, S Okamura, S Matsuoka, K TI Escaping fast ion diagnostics in compact helical system heliotron/torsatron SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 12th Topical Conference on High-Temperature Plasma Diagnostics CY JUN 07-11, 1998 CL PRINCETON, NEW JERSEY SP Amer Phys Soc, Off Def Programs, US Dept Energy, Off Fus Energy, Princeton Plasma Phys Lab ID FUSION TEST REACTOR; BEHAVIOR; PRODUCTS; PLASMAS; LOSSES; TFTR AB Escaping energetic ions have been measured with a scintillator-based probe which can provide both information of pitch angle and gyroradius of detected ions in compact helical system. The measurement was started in February 1997. It was confirmed that output signals are due to neutral beam-injected fast ions. A Lorentz orbit code was developed and fast ion orbits reaching the probe were computed to understand the loss process of detected ions. Birthplace and initial pitch angle of fast ions were calculated by a Monte Carlo beam deposition code HFREYA. From the comparison between pitch angle variation of computed fast ion orbits and pitch angle distribution of birth fast ions, it turns out that fast ions whose birthplace is in the core region cannot reach the detection point directly. (C) 1999 American Institute of Physics. [S0034-6748(99)64601-9]. C1 Natl Inst Fus Sci, Toki 5095292, Japan. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Grad Univ Adv Studies, Dept Fus Sci, Toki 5095292, Japan. Nagoya Univ, Dept Energy Engn Sci, Nagoya, Aichi 4640814, Japan. RP Isobe, M (reprint author), Natl Inst Fus Sci, Oroshi Cho, Toki 5095292, Japan. RI Murakami, Sadayoshi/A-2191-2016 OI Murakami, Sadayoshi/0000-0002-2526-7137 NR 16 TC 41 Z9 41 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 1999 VL 70 IS 1 BP 827 EP 830 DI 10.1063/1.1149404 PN 2 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 161FQ UT WOS:000078278900147 ER EF