%0 Journal Article
%T Varying Faces of Photospheric Emission in Gamma-Ray Bursts
%A M. Axelsson
%A for the Fermi-LAT Collaboration
%J Physics
%D 2015
%I arXiv
%X 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.
%U http://arxiv.org/abs/1502.03171v1