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arXiv · 1502.03053

Fermi/LAT Study of the Cygnus Loop Supernova Remnant: Discovery of a Point-like Source and of Spectral Differences in its gamma-ray emission

I. Reichardt·R. Terrier·J. West·S. Safi-Harb·E. de Oña-Wilhelmi·J. Rico
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Abstract

The Cygnus Loop is a nearby supernova remnant (SNR) observed across the electromagnetic spectrum. With the analysis of 6 years of Fermi/LAT data we find that, what previous studies had considered a single source, consists of an extended source plus a point-like source south-east of the SNR. The extended gamma-ray emission is well correlated with the thermal X-ray emission of the SNR, and the energy spectrum displays a pronounced maximum at $\sim0.6$\,GeV. However, in a region where the radio emission is strongly and distinctly polarized, the gamma-ray spectrum shows no sign of a break. Therefore, the spatially resolved gamma-ray emission permits the study of different interaction conditions of the SNR and the surrounding medium.

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I. Reichardt, R. Terrier, J. West, S. Safi-Harb, E. de Oña-Wilhelmi, J. Rico. 2015-03-03. Fermi/LAT Study of the Cygnus Loop Supernova Remnant: Discovery of a Point-like Source and of Spectral Differences in its gamma-ray emission. https://arxiv.org/abs/1502.03053

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