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arXiv · 1310.8287

Fermi-LAT Detection of a Break in the Gamma-Ray Spectrum of the Supernova Remnant Cassiopeia A

Y. Yuan·S. Funk·G. Jóhannesson·J. Lande·L. Tibaldo·Y. Uchiyama
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Abstract

We report on observations of the supernova remnant Cassiopeia A in the energy range from 100 MeV to 100 GeV using 44 months of observations from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. We perform a detailed spectral analysis of this source and report on a low-energy break in the spectrum at $1.72^{+1.35}_{-0.89}$ GeV. By comparing the results with models for the gamma-ray emission, we find that hadronic emission is preferred for the GeV energy range.

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Y. Yuan, S. Funk, G. Jóhannesson, J. Lande, L. Tibaldo, Y. Uchiyama. 2013-10-30. Fermi-LAT Detection of a Break in the Gamma-Ray Spectrum of the Supernova Remnant Cassiopeia A. https://doi.org/10.1088/0004-637x%2F779%2F2%2F117

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