Published March 15, 1980
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Journal Article
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The isotopic composition of galactic cosmic-ray iron nuclei
Abstract
We report high-resolution observations made in interplanetary space of 83-284 MeV per nucleon galactic cosmic-ray iron isotopes and directly establish that ^(56)Fe is the dominant cosmic-ray Fe isotope. We find the following percentage abundances for Fe at the cosmic-ray source: ^(54)Fe = 9(+8, -5)%, ^(55)Fe ≤ 7%, ^(56)Fe = 91(+5, -11)%, ^(57)Fe ≤ 8%, and ^(58)Fe ≤ 6%. When compared to calculated nucleosynthesis yields and other observations, these results place significant constraints on the neutron excess of the environment where cosmic-ray Fe originates.
Additional Information
© 1980 American Astronomical Society. Received 1979 October 9; accepted 1979 November 28. W. E. Althouse, A. C. Cummings, and T. L. Garrard made significant contributions to the design and development of HIST. We are grateful to the Heckman/Greiner group, including Hank Crawford, and the Bevalac staff at Lawrence Berkeley Laboratory for making the heavy-ion calibrations possible. This work was supported in part by NASA under contract NASS-20721 and grant NGR 05-002-160.Attached Files
Published - 1980ApJ___236L_121M.pdf
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1980ApJ___236L_121M.pdf
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- 43739
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- CaltechAUTHORS:20140210-112418931
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- http://adsabs.harvard.edu/abs/1980ApJ...236L.121M (URL)
Funding
- NASA
- NAS5-20721
- NASA
- NGR 05-002-160
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2014-02-10Created from EPrint's datestamp field
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2021-11-10Created from EPrint's last_modified field
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