Antimatter spectra from a time-dependent modeling of supernova remnants

Abstract

We calculate the energy spectra of cosmic rays (CR) and their secondaries produced in a supernova remnant (SNR), taking into account the time-dependence of the SNR shock. We model the trajectories of charged particles as a random walk with a prescribed diffusioncoefficient, accelerating the particles at each shock crossing. Secondary production by CRs colliding with gas is included as a Monte Carlo process. We find that SNRs produce less antimatter than suggested previously: The positron/electron ratio and the antiproton/proton ratio are a few percent and few $\times 10^{-5}$, respectively. Both ratios do not rise with energy.

4 pages, 4 eps figures; v2: results for time-dependent magnetic field added

References in corpus (5)

• Observation of an anomalous positron abundance in the cosmic radiation
• A new measurement of the antiproton-to-proton flux ratio up to 100 GeV in the cosmic radiation
• The origin of the positron excess in cosmic rays
• High-energy antiprotons from old supernova remnants
• Testing astrophysical models for the PAMELA positron excess with cosmic ray nuclei