Antimatter spectra from a time-dependent modeling of supernova remnants

TL;DR

This paper models the time-dependent energy spectra of cosmic rays and their secondaries in supernova remnants, revealing lower antimatter production than previously estimated and that these ratios do not increase with energy.

Contribution

It introduces a time-dependent model of supernova remnants that accounts for shock evolution and secondary production, providing more accurate estimates of antimatter ratios in cosmic rays.

Findings

SNRs produce less antimatter than previously thought.

Positron/electron and antiproton/proton ratios are a few percent and 10^-5.

Ratios do not increase with energy.

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.