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The Origin of Primary Cosmic Rays: Constraints from ACE Elemental and Isotopic Composition Observations

Wiedenbeck, M. E. and Yanasak, N. E. and Cummings, A. C. and Davis, A. J. and George, J. S. and Leske, R. A. and Mewaldt, R. A. and Stone, E. C. and Hink, P. L. and Israel, M. H. and Lijowski, M. and Christian, E. R. and von Rosenvinge, T. T. (2001) The Origin of Primary Cosmic Rays: Constraints from ACE Elemental and Isotopic Composition Observations. In: The Astrophysics of Galactic Cosmic Rays. Space Sciences Series of ISSI. No.13. Springer Netherlands , Dordrecht, pp. 15-26. ISBN 9789048158621.

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Cosmic-ray isotope observations from NASA’s Advanced Composition Explorer (ACE) mission have been used to investigate the composition of cosmic-ray source material. Source abundances relative to ⁵⁶Fe are reported for eleven isotopes of Ca, Fe, Co, and Ni, including the very rare isotopes ⁴⁸Ca and ⁶⁴Ni. Although the source abundances range over a factor ~ 10⁴, most of the ratios to ⁵⁶Fe are consistent with solar-system values to within ~ 20%. However, there are some notable differences, the most significant being an excess of ~ (70 ± 30)% relative to the solar system for the cosmic-ray source ratio ⁵⁸Fe/⁵⁶Fe. The possible association of such an excess with a contribution to the cosmic-ray source from Wolf—Rayet star ejecta is discussed.

Item Type:Book Section
Related URLs:
URLURL TypeDescription Section ReadCube access ItemJournal Article
Wiedenbeck, M. E.0000-0002-2825-3128
Cummings, A. C.0000-0002-3840-7696
Leske, R. A.0000-0002-0156-2414
Mewaldt, R. A.0000-0003-2178-9111
Stone, E. C.0000-0002-2010-5462
Israel, M. H.0000-0002-8104-208X
Christian, E. R.0000-0003-2134-3937
Additional Information:© Kluwer Academic Publishers. 2001. (Received 29 September 2000; Accepted in final form: 15 January 2001) We are grateful to the large group of dedicated individuals that participated in the development of the CRIS instrument (listed in Stone et al., 1998). We also thank J. Klarmann for contributions to the CRIS data analysis. This research was supported by the National Aeronautics and Space Administration at the California Institute of Technology (under grant NAG5-6912), the Jet Propulsion Laboratory, the Goddard Space Plight Center, and Washington University.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
Goddard Space Flight CenterUNSPECIFIED
Washington UniversityUNSPECIFIED
Series Name:Space Sciences Series of ISSI
Issue or Number:13
Record Number:CaltechAUTHORS:20200506-160349946
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:103053
Deposited By: George Porter
Deposited On:07 May 2020 18:46
Last Modified:16 Nov 2021 18:17

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