First Result from the Alpha Magnetic Spectrometer on the International Space Station: Precision Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5–350 GeV
Author(s)
Basil, A.; Becker, R.; Becker, Ulrich J.; Behlmann, Matthew Daniel; Berges, P.; Burger, Joseph D.; Cai, X. D.; Capell, Michael H.; Chen, Andrew I.; Chen, H.; Choumilov, Evgueni; Choutko, Vitali; Dennett, P.; Egorov, A.; Eline, Alexandre; Eppling, Frederic J.; Fisher, Peter H.; Flood, Kevin T.; Galaktionov, Y.; Gallilee, M.; Gargiulo, C.; Goglov, Pavel; Hungerford, W.; Incagli, M.; Koulemzine, A.; Kounina, Olga; Kounine, Andrei; Koutsenko, Vladimir; Krafczyk, Matthew Scott; Lebedev, Ilia A.; Plyaskin, V.; Rozhkov, A.; Schinzel, D.; Steuer, V.; Sun, W.; Ting, Samuel C. C.; Ting, S. M.; Titus, Christine; Vaurynovich, Siarhei S.; Vergain, M.; Wang, X.; Willenbrock, M.; Zuccon, Paolo; P. Berges; ... Show more Show less
DownloadAguilar-2013-First Result from the Alpha Magnetic S.pdf (610.6Kb)
PUBLISHER_POLICY
Publisher Policy
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Terms of use
Metadata
Show full item recordAbstract
A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8×10[superscript 6] positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼250 GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.
Date issued
2013-04Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science; Massachusetts Institute of Technology. Department of Physics; Massachusetts Institute of Technology. Laboratory for Nuclear ScienceJournal
Physical Review Letters
Publisher
American Physical Society
Citation
Aguilar, M. et al. “First Result from the Alpha Magnetic Spectrometer on the International Space Station: Precision Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5–350 GeV.” Physical Review Letters 110.14 (2013). © 2013 American Physical Society
Version: Final published version
ISSN
0031-9007
1079-7114