likely Detection of GeV gamma-Ray Emission from the composite supernova remnant COMP G327.1+1.1 with Fermi-LAT

TL;DR

This study reports the detection of GeV gamma-ray emission from the supernova remnant COMP G327.1+1.1 using Fermi-LAT data, suggesting a likely association and modeling its spectral energy distribution with leptonic and hadronic models.

Contribution

First detection of GeV gamma-ray emission from COMP G327.1+1.1 and modeling of its broadband spectrum with simple stationary models.

Findings

Gamma-ray emission consistent with known SNRs in the Milky Way.

Two-zone leptonic model better explains the spectral energy distribution.

Future high-energy observations needed for confirmation.

Abstract

We report the likely GeV $\gamma$-ray emission from the composite supernova remnant (SNR) COMP G327.1+1.1 by analyzing $\sim$12.2 years of the \textit{Fermi} Large Area Telescope (\textit{Fermi}-LAT) Pass 8 data. We found the features of its \textbf{ranges of} spectrum and luminosity are well consistent with those of the observed COMP SNRs in the Milky Way. Moreover, the position of the source matches those in radio and TeV energy bands, we propose that the $\gamma$-ray source is likely to be a GeV counterpart of COMP G327.1+1.1. Considering the case of the association from COMP G327.1+1.1 and the $\gamma$-ray source, we interpreted its broadband spectral energy distribution (SED) by using three simple stationary models including one-zone and two-zone leptonic models and one-zone leptohadronic model. We found that the simple two-zone model dominated by leptons can better explain its SED. More high-energy data are expected to firmly confirm the association between the $\gamma$-ray source and COMP G327.1+1.1 in the future.