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arXiv · 1711.03729

Detection of GeV $\gamma$-ray emission in the direction of HESS J1731-347 with Fermi-LAT

Xiao-Lei Guo·Yu-Liang Xin·Neng-Hui Liao·Qiang Yuan·Wei-Hong Gao·Yi-Zhong Fan
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Abstract

We report the detection of GeV $\gamma$-ray emission from supernova remnant HESS J1731-347 using 9 years of {\it Fermi} Large Area Telescope data. We find a slightly extended GeV source in the direction of HESS J1731-347. The spectrum above 1 GeV can be fitted by a power-law with an index of $\Gamma = 1.77\pm0.14$, and the GeV spectrum connects smoothly with the TeV spectrum of HESS J1731-347. Either a hadronic-leptonic or a pure leptonic model can fit the multi-wavelength spectral energy distribution of the source. However, the hard GeV $\gamma$-ray spectrum is more naturally produced in a leptonic (inverse Compton scattering) scenario, under the framework of diffusive shock acceleration. We also searched for the GeV $\gamma$-ray emission from the nearby TeV source HESS J1729-345. No significant GeV $\gamma$-ray emission is found, and upper limits are derived.

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Xiao-Lei Guo, Yu-Liang Xin, Neng-Hui Liao, Qiang Yuan, Wei-Hong Gao, Yi-Zhong Fan. 2017-11-10. Detection of GeV $\gamma$-ray emission in the direction of HESS J1731-347 with Fermi-LAT. https://doi.org/10.3847/1538-4357%2Faaa3f8

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