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Measurement of 0.25–3.2 GeV Antiprotons in the Cosmic Radiation

Mitchell, J. W. and Barbier, L. M. and Christian, E. R. and Krombel, K. E. and Ormes, J. F. and Streitmatter, R. E. and Labrador, A. W. and Davis, A. J. and Mewaldt, R. A. and Schindler, S. M. and Golden, R. L. and Stochaj, S. J. and Webber, W. R. and Menn, W. and Hof, M. and Reimer, O. and Simon, M. (1996) Measurement of 0.25–3.2 GeV Antiprotons in the Cosmic Radiation. Physical Review Letters, 76 . pp. 3057-3060. ISSN 0031-9007. doi:10.1103/PhysRevLett.76.3057.

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The balloon-borne Isotope Matter-Antimatter Experiment (IMAX) was flown from Lynn Lake, Manitoba, Canada on 16–17 July 1992. Using velocity and magnetic rigidity to determine mass, we have directly measured the abundances of cosmic ray antiprotons and protons in the energy range from 0.25 to 3.2 GeV. Both the absolute flux of antiprotons and the antiproton/proton ratio are consistent with recent theoretical work in which antiprotons are produced as secondary products of cosmic ray interactions with the interstellar medium. This consistency implies a lower limit to the antiproton lifetime of ∼10^7yr.

Item Type:Article
Related URLs:
URLURL TypeDescription
Christian, E. R.0000-0003-2134-3937
Labrador, A. W.0000-0001-9178-5349
Mewaldt, R. A.0000-0003-2178-9111
Hof, M.0000-0003-2884-3037
Additional Information:© 1996 The American Physical Society. (Received 30 August 1995; revised manuscript received 4 December 1995) We thank Glen Albritton, Barbara Kimbell Golden, Steve Holder, Bob Hull, Roy Park, and Don Righter for dedicated technical support; Francesco Cafagna (U. Bari, Italy) and Heather Muise for help with GEANT; and the National Scientific Balloon Facility for the IMAX flight. IMAX was supported in the U.S. by NASA RTOP 353-87-02 (GSFC) and Grants NAGW-1919 (Caltech) and NAGW-1418 (NMSU) and in Germany by DARA 50QV9191 and DFG Si-290y7.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASARTOP 353-87-02
Deutsche Forschungsgemeinschaft (DFG)Si-290/7
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1995-40
Record Number:CaltechAUTHORS:20140619-162055642
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:46378
Deposited By: Deborah Miles
Deposited On:20 Jun 2014 18:27
Last Modified:10 Nov 2021 17:24

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