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arXiv · 1502.03171

Varying Faces of Photospheric Emission in Gamma-Ray Bursts

M. Axelsson
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Abstract

Among the more than 1000 gamma-ray bursts observed by the Fermi Gamma-ray Space Telescope, a large fraction show narrow and hard spectra inconsistent with non-thermal emission, signifying optically thick emission from the photosphere. However, only a few of these bursts have spectra consistent with a pure Planck function. We will discuss the observational features of photospheric emission in these GRBs as well as in the ones showing multi-component spectra. We interpret the observations in light of models of subphotospheric dissipation, geometrical broadening and multi-zone emission, and show what we can learn about the dissipation mechanism and properties of GRB jets.

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M. Axelsson. 2015-02-11. Varying Faces of Photospheric Emission in Gamma-Ray Bursts. https://arxiv.org/abs/1502.03171

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