Search Results - "Westphal, J. A"

Helium and neon in comet 81P/Wild 2 samples from the NASA Stardust mission by Palma, R. L., Pepin, R. O., Westphal, A. J., Füri, E., Schlutter, D. J., Gainsforth, Z. S., Frank, D. R.

“…Helium and neon distributions are reported for a variety of Stardust comet 81P/Wild 2 samples, including particle tracks and terminal particles, cell surface…”
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Kosmochloric Ca-rich pyroxenes and FeO-rich olivines (Kool grains) and associated phases in Stardust tracks and chondritic porous interplanetary dust particles: Possible precursors to FeO-rich type II chondrules in ordinary chondrites by Joswiak, D. J., Brownlee, D. E., Matrajt, G., Westphal, A. J., Snead, C. J.

“…— Terminal particles and mineral fragments from comet 81P/Wild 2 were studied in 16 aerogel tracks by transmission and secondary electron microscopy. In eight…”
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Infrared spectroscopy of Wild 2 particle hypervelocity tracks in Stardust aerogel: Evidence for the presence of volatile organics in cometary dust by BAJT, S., SANDFORD, S. A., FLYNN, G. J., MATRAJT, G., SNEAD, C. J., WESTPHAL, A. J., BRADLEY, J. P.

“…— Infrared spectroscopy maps of some tracks made by cometary dust from 81P/Wild 2 impacting Stardust aerogel reveal an interesting distribution of organic…”
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Model for quantitative tip-enhanced spectroscopy and the extraction of nanoscale-resolved optical constants by McLeod, Alexander S., Kelly, P., Goldflam, M. D., Gainsforth, Z., Westphal, A. J., Dominguez, Gerardo, Thiemens, Mark H., Fogler, Michael M., Basov, D. N.

“…Near-field infrared spectroscopy by elastic scattering of light from a probe tip resolves optical contrasts in materials at dramatically subwavelength scales…”
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Mixing Fraction of Inner Solar System Material in Comet 81P/Wild2 by Westphal, A. J, Fakra, S. C, Gainsforth, Z, Marcus, M. A, Ogliore, R. C, Butterworth, A. L

“…The presence of crystalline silicates in the comae of comets, inferred through infrared observations, has been a long-standing puzzle. Crystalline silicates…”
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Nebular mixing constrained by the Stardust samples by Ogliore, R. C., Westphal, A. J., Gainsforth, Z., Butterworth, A. L., Fakra, S. C., Marcus, M. A.

“…— Using X‐ray microprobe analysis of samples from comet Wild 2 returned by the Stardust mission, we determine that the crystalline Fe‐bearing silicate fraction…”
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Formation of Glass with Embedded Metal and Sulfides from Shock-accelerated Crystalline Dust in Superbubbles by Westphal, A. J, Bradley, J. P

“…Interplanetary dust particles (IDPs) contain enigmatic submicron components called GEMS (glass with embedded metal and sulfides). The compositions and…”
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Compositional evidence for chondrule origins of low‐Ca pyroxenes in comet Wild 2 and a giant cluster IDP by Joswiak, D. J., Brownlee, D. E., Westphal, A. J., Gainsforth, Z., Zhang, M., Kita, N. T.

“…A literature compilation of 1136 low‐Ca pyroxene compositions from chondrules from 12 primitive type 2–3 carbonaceous, ordinary and enstatite chondrite groups…”
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Extended Analysis of the Trek Ultraheavy Collector by Weaver, B. A, Westphal, A. J

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Gems at the galactic cosmic-ray source by WESTPHAL, A. J, DAVIS, A. M, LEVINE, J, PELLIN, M. J, SAVINA, M. R

“…Issue Title: The Composition of Matter Galactic cosmic rays probably predominantly originate from shock-accelerated gas and dust in superbubbles. It is usually…”
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Fine‐grained material associated with a large sulfide returned from Comet 81P/Wild 2 by Gainsforth, Z., Westphal, A. J., Butterworth, A. L., Jilly‐Rehak, C. E., Brownlee, D. E., Joswiak, D. J., Ogliore, R. C., Zolensky, M. E., Bechtel, H. A., Ebel, D. S., Huss, G. R., Sandford, S. A., White, A. J.

“…In a consortium analysis of a large particle captured from the coma of comet 81P/Wild 2 by the Stardust spacecraft, we report the discovery of a field of…”
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The future of Stardust science by Westphal, A. J., Bridges, J. C., Brownlee, D. E., Butterworth, A. L., De Gregorio, B. T., Dominguez, G., Flynn, G. J., Gainsforth, Z., Ishii, H. A., Joswiak, D., Nittler, L. R., Ogliore, R. C., Palma, R., Pepin, R. O., Stephan, T., Zolensky, M. E.

“…Recent observations indicate that >99% of the small bodies in the solar system reside in its outer reaches—in the Kuiper Belt and Oort Cloud. Kuiper Belt…”
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Comparison of the oxidation state of Fe in comet 81P/Wild 2 and chondritic-porous interplanetary dust particles by Ogliore, R.C., Butterworth, A.L., Fakra, S.C., Gainsforth, Z., Marcus, M.A., Westphal, A.J.

“…The fragile structure of chondritic-porous interplanetary dust particles (CP-IDPs) and their minimal parent-body alteration have led researchers to believe…”
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RIO: the R-process isotope observer by Weaver, B.A., Westphal, A.J.

“…Our galaxy is filled with a “gas” of relativistic nuclei and electrons – the galactic cosmic rays (GCRs). The source of GCR nuclei is unknown, but there is a…”
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Nuclear track-formation models and the response of BP-1 detectors by Weaver, B.A., Westphal, A.J.

“…The mechanism of nuclear track formation in solids is poorly understood, despite decades of experience with nuclear track-etch detectors. One of the roadblocks…”
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Main-Sequence Stars and the Star Formation History of the Outer Disk in the Large Magellanic Cloud by Gallagher, J. S., Mould, J. R., de Feijter, E., Holtzman, J., Stappers, B., Watson, A., Trauger, J., Ballester, G. E., Burrows, C. J., Casertano, S., Clarke, J. T., Crisp, D., Griffiths, R. E., Hester, J. J., Hoessel, J., Krist, J., Matthews, L. D., Scowen, P. A., Stapelfeld, K. R., Westphal, J. A.

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Stage-Discharge Relations on the Middle Mississippi River by Westphal, J. A, Thompson, D. B, Jr, G. T. Stevens, Strauser, C. N

“…Based on measurements made on the Middle Mississippi River during the 1993 flood, stage-discharge relations for the rating curve are not single-valued…”
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Kinetics of Size Changes of Individual Bacillus thuringiensis Spores in Response to Changes in Relative Humidity by Westphal, Andrew J., Price, P. Buford, Leighton, Terrance J., Wheeler, Katherine E.

“…Using an automated scanning microscope, we report the surprising result that individual dormant spores of Bacillus thuringiensis grow and shrink in response to…”
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Preliminary results from the extended-trek detector by Weaver, B.A., Westphal, A.J.

“…Extended-Trek is the continuation of the Trek ultraheavy cosmic-ray project. The Trek detector consisted of an array of stacks of 16 sheets of BP-1 track-etch…”
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Aerogel keystones: Extraction of complete hypervelocity impact events from aerogel collectors by Westphal, Andrew J., Snead, Christopher, Butterworth, Anna, Graham, Giles A., Bradley, John P., Bajt, Saša, Grant, Patrick G., Bench, Graham, Brennan, Sean, Pianetta, Piero

“…— In January 2006, the Stardust mission will return the first samples from a solid solar system body beyond the Moon and the first samples of contemporary…”
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