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The Cosmic Ray ^3He/^4He Ratio from 200 MeV per Nucleon^(-1) to 3.7 GeV per Nucleon^(-1)

Reimer, O. and Menn, W. and Hof, M. and Simon, M. and Davis, A. J. and Labrador, A. W. and Mewaldt, R. A. and Schindler, S. M. and Barbier, L. M. and Christian, E. R. and Krombel, K. E. and Mitchell, J. W. and Ormes, J. F. and Streitmatter, R. E. and Golden, R. L. and Stochaj, S. J. and Webber, W. R. and Rassmussen, I. L. (1998) The Cosmic Ray ^3He/^4He Ratio from 200 MeV per Nucleon^(-1) to 3.7 GeV per Nucleon^(-1). Astrophysical Journal, 496 . pp. 490-502. ISSN 0004-637X.

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The abundances of cosmic-ray helium isotopes between 0.2 and 3.7 GeV nucleon^(-1) were measured by the Isotope Matter Antimatter Experiment (IMAX) during a flight from Lynn Lake, Manitoba, Canada on 1992 July 16-17. The IMAX balloon-borne magnetic spectrometer realized a direct measurement of the charge, the velocity, and the rigidity of cosmic rays using plastic scintillators, a high-resolution time-of-flight system, and two silica-aerogel Cerenkov counters in conjunction with a drift chamber/multiwire proportional chamber tracking system. About 75,000 helium isotopes are identified by their mass using the velocity versus magnetic rigidity technique. The measured ^3He/^4He ratios are corrected to the top of the atmosphere, and a comparison with previous data is given. The observed isotopic composition is found to be generally consistent with the predictions of a standard leaky box model of cosmic-ray transport in the Galaxy.

Item Type:Article
Related URLs:
URLURL TypeDescription ADS Astronomy Abstract Service
Hof, M.0000-0003-2884-3037
Labrador, A. W.0000-0001-9178-5349
Mewaldt, R. A.0000-0003-2178-9111
Christian, E. R.0000-0003-2134-3937
Alternate Title:Cosmic-Ray 3He/4He Ratio from 200 MeV per Nucleon-1 to 3.7 GeV per Nucleon-1
Additional Information:c1998 The American Astronomical Society. Received 1997 May 19; accepted 1997 October 24. We thank the technical crews from New Mexico State University, Goddard Space Flight Center, California Institute of Technology, and the Universita�t Siegen for their dedicated support. We are grateful to the National Scientific Balloon Facility for carrying out a successful flight of the IMAX payload. The IMAX project was supported in the United States by NASA under RTOP 353-87-02 (GSFC) and grants NAGW-1418 (NMSU/BBMF) and NAGW-1919 (Caltech) and in Germany by the Deutsche Forschungsgemeinschaft (DFG) and the Bundesministerium fu�r Bildung, Wissenschaft, Forschung, und Technologie (BMBF).
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASARTOP 353-87-02
Subject Keywords:acceleration of particles - balloons - cosmic rays - nuclear reactions, nucleosynthesis, abundances
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1997-24
Record Number:CaltechAUTHORS:20141106-082254240
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:51346
Deposited By: Deborah Miles
Deposited On:11 Nov 2014 21:42
Last Modified:09 Mar 2020 13:18

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