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Anomalous cosmic ray composition from ACE

Leske, R. A. (2000) Anomalous cosmic ray composition from ACE. In: 26th International Cosmic Ray Conference. AIP Conference Series. No.516. American Institute of Physics , Melville, New York, pp. 274-282. ISBN 1563969394.

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During solar quiet periods, the Solar Isotope Spectrometer (SIS) on the Advanced Composition Explorer (ACE) measures the composition and energy spectra of anomalous cosmic rays (ACRs) with energies >8 MeV/nucleon in interplanetary space at 1 AU. In particular, the spectra of individual isotopes for the ACR elements N, O, and Ne are studied with SIS. Intensity enhancements are found in low energy 18O and 22Ne, with relative abundances of ^(18)O/^(16)O ~ 0.002 and ^(22)Ne/^(20)Ne ~ 0.1. The neon abundance ratio appears more similar to that found in the solar wind than in meteorites and is far below that determined for the galactic cosmic ray (GCR) source, indicating that GCRs contain material from sources other than just the local interstellar medium.

Item Type:Book Section
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Leske, R. A.0000-0002-0156-2414
Additional Information:© 2000 American Institute of Physics. Issue Date: 13 June 2000. This research was supported by NASA at the California Institute of Technology (under grant NAG5-6912), the Jet Propulsion Laboratory, and the Goddard Space Flight Center. We thank the large group of individuals who contributed to the development of the SIS instrument [17] and the SIS science collaborators R. A. Mewaldt, E. R. Christian, C. M. S. Cohen, A. C. Cummings, P. L. Slocum, E. C. Stone, T. T. von Rosenvinge, and M. E. Wiedenbeck. Climax neutron monitor data were obtained from the web, courtesy of the University of Chicago, National Science Foundation grant ATM-9613963.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
Goddard Space Flight CenterUNSPECIFIED
Subject Keywords:galactic cosmic rays; cosmic ray composition; cosmic ray energy spectra; isotope relative abundance; meteorites, solar wind; cosmic ray apparatus
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory2000-50
Series Name:AIP Conference Series
Issue or Number:516
Classification Code:PACS: 96.40.De; 95.85.Ry;
Record Number:CaltechAUTHORS:20111201-093626829
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Official Citation:Anomalous cosmic ray composition from ACE R. A. Leske, AIP Conf. Proc. 516, 274 (2000), DOI:10.1063/1.1291481
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:28268
Deposited On:05 Dec 2011 16:07
Last Modified:09 Nov 2021 16:55

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