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B/C ratio and the PAMELA positron excess

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 نشر من قبل Michael Kachelrie{\\ss}
 تاريخ النشر 2012
  مجال البحث فيزياء
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We calculate the diffuse intensity of cosmic ray (CR) nuclei and their secondaries in the Boron-Carbon group produced by supernova remnants (SNR). The trajectories of charged particles in the SNR are modeled as a random walk in the test particle approximation. Secondary production by CRs colliding with gas in the SNR is included as a Monte Carlo process, while we use Galprop to account for the propagation and interactions of CRs in the Galaxy. In the vicinity of a source, we find an approximately constant B/C ratio as a function of energy. As a result, the B/C ratio at Earth does not rise with energy, but flattens instead in the high energy limit. This prediction can be soon tested by the AMS-2 collaboration.



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