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The isotopic composition of galactic cosmic-ray iron nuclei

Mewaldt, R. A. and Spalding, J. D. and Stone, E. C. and Vogt, R. E. (1980) The isotopic composition of galactic cosmic-ray iron nuclei. Astrophysical Journal, 236 . L121-L125. ISSN 0004-637X. doi:10.1086/183211.

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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.

Item Type:Article
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URLURL TypeDescription
Mewaldt, R. A.0000-0003-2178-9111
Stone, E. C.0000-0002-2010-5462
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.
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NASANGR 05-002-160
Subject Keywords:cosmic rays: abundances, nucleosynthesis
Record Number:CaltechAUTHORS:20140210-112418931
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Official Citation:The isotopic composition of galactic cosmic-ray iron nuclei Mewaldt, R. A., Spalding, J. D., Stone, E. C., & Vogt, R. E. Astrophysical Journal, Part 2 - Letters to the Editor, vol. 236, Mar. 15, 1980, p. L121-L125.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:43739
Deposited By: Ruth Sustaita
Deposited On:10 Feb 2014 21:01
Last Modified:10 Nov 2021 16:42

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