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A Measurement of the Isotopic Composition of Cosmic Ray Iron

Grove, J. E. and Christian, E. R. and Mewaldt, R. A. and Schindler, S. M. and Stone, E. C. and Buffington, A. and Rasmussen, I. L. (1990) A Measurement of the Isotopic Composition of Cosmic Ray Iron. In: Proceedings of the 21st International Cosmic Ray Conference. Vol.3. University of Adelaide , Northfield, South Australia, pp. 53-56.

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We present a new measurement of the isotopic composition of cosmic ray iron in the energy interval ~1550-2200 MeV /nucleon. The data were collected during the May 1984 flight of a balloon-borne spectrometer and show an average mass resolution of ~0.7 amu. The instrument employed the Cerenkov-Energy technique for mass determination. The observed ^(54)Fe/^(56)Fe ratio, 0.14 +0.18/-0.11 at the top of the atmosphere, is consistent with a solar system composition at the cosmic ray source. We also place an upper limit on the ^(58)Fe/^(56)Fe ratio at the top of the atmosphere of ≤.07. Both are consistent with previous measurements at lower energies.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Christian, E. R.0000-0003-2134-3937
Mewaldt, R. A.0000-0003-2178-9111
Stone, E. C.0000-0002-2010-5462
Additional Information:© Organizing Committee of the 21st Int. Cosmic Ray Conf. Provided by the NASA Astrophysics Data System. This work was supported in part by NASA under grant NGR 05- 002-160. We are grateful to P. S. Gibner for his contributions to this work and to the personnel of the National Scientific Balloon Facility and the Wallops Flight Facility for their excellent support.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASANCR 05-002-160
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1989-14
Record Number:CaltechAUTHORS:20140509-091626822
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45633
Deposited By: Joy Painter
Deposited On:09 May 2014 16:36
Last Modified:09 Mar 2020 13:18

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