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arXiv · 2106.03008

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

Rita C. dos Anjos·Jaziel G. Coelho·Jonas P. Pereira·Fernando Catalani
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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.

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Rita C. dos Anjos, Jaziel G. Coelho, Jonas P. Pereira, Fernando Catalani. 2021-06-06. High-energy gamma-ray emission from SNR G57.2+0.8 hosting SGR J1935+2154. https://doi.org/10.1088/1475-7516/2021/10/023

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