High-energy gamma-ray emission from SNR G57.2+0.8 hosting SGR J1935+2154

TL;DR

This paper models the high-energy gamma-ray emission from SNR G57.2+0.8 hosting SGR J1935+2154, suggesting it as a potential source of cosmic rays and contributing to the Galactic center's TeV gamma-ray background.

Contribution

It introduces a combined SNR and SGR model using GALPROP to explain gamma-ray emissions and their role in cosmic-ray acceleration.

Findings

SNR G57.2+0.8 and SGR J1935+2154 can produce significant gamma-ray emission.

The model accounts for the gamma-ray contribution to the Galactic center.

The combined source scenario offers a comprehensive explanation for observed TeV gamma-rays.

Abstract

In recent years some efforts have been made to identify active sources capable of accelerating particles up to $10^{15}$ eV, known as PeVatrons. Measurements of TeV ($10^{12}$ eV) gamma-rays from supernova remnants (SNRs) have shown that efficient particle acceleration can occur in SNR diffusive shocks. In this paper, we obtain the contribution to the high energy and very-high-energy gamma-ray (VHE, $E > 100$ GeV) emission due to cosmic-ray acceleration from SNR G57.2+0.8 hosting the Soft Gamma Repeater (SGR) J1935+2154 with the use of the GALPROP code. To do so, we take into account the SNR + SGR association as a single source close to the Galactic center. We propose that the above setting can provide a more comprehensive scenario for the generation of GeV-TeV gamma-rays. We also discuss the contribution from the SNR G57.2+0.8 and SGR J1935+2154 region to the diffusive TeV energy gamma-ray emission from the Galactic center.