A Caltech Library Service

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.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We report high-resolution observations made in interplanetary space of 83-284 MeV per nucleon galactic cosmic-ray iron isotopes are reported and it is directly established that ^(56)Fe is the dominant cosmic-ray Fe isotope. The following percentage abundances for Fe at the cosmic-ray source are found: ^(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
Related URLs:
URLURL TypeDescription
Mewaldt, R. A.0000-0003-2178-9111
Stone, E. C.0000-0002-2010-5462
Contact Email
Additional Information:© 1980. The 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 NAS5-20721 and grant NGR 05-002-160.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASANGR 05-002-160
Subject Keywords:Abundance, Cosmic Rays, Galactic Radiation, Iron Isotopes, Nuclear Fusion, Nuclei (Nuclear Physics), International Sun Earth Explorer 3, Iron 57, Mass Ratios
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1979-11
Record Number:CaltechAUTHORS:20140417-135449903
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45014
Deposited By: SWORD User
Deposited On:28 Apr 2014 22:52
Last Modified:10 Nov 2021 16:59

Repository Staff Only: item control page