Cosmic Ray Antiprotons from Nearby Cosmic Accelerators

TL;DR

This paper investigates whether nearby supernova remnants contribute to the cosmic ray antiproton flux observed near Earth by analyzing gamma-ray emissions and their origins in hadronic interactions.

Contribution

It models the contribution of specific nearby supernova remnants to the cosmic ray antiproton flux using gamma-ray data from Fermi LAT observations.

Findings

Nearby SNRs can significantly contribute to the local antiproton flux.

Gamma-ray emissions from SNRs are consistent with hadronic origin.

Quantitative estimates of SNR contributions to cosmic ray antiprotons.

Abstract

The antiproton flux measured by PAMELA experiment might have originated from Galactic sources of cosmic rays. These antiprotons are expected to be produced in the interactions of cosmic ray protons and nuclei with cold protons. Gamma rays are also produced in similar interactions inside some of the cosmic acceleratos. We consider a few nearby supernova remnants observed by Fermi LAT. Many of them are associated with molecular clouds. Gamma rays have been detected from these sources which most likely originate in decay of neutral pions produced in hadronic interactions. The observed gamma ray fluxes from these SNRs are used to find out their contributions to the observed diffuse cosmic ray antiproton flux near the earth.