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arXiv · 1202.2821

Single- and Two-Component GRB Spectra in the Fermi GBM-LAT Energy Range

P. Veres·P. Mészáros
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Abstract

Most Fermi GRB spectra appear as either a broken power law extending to GeV energies or as a broken power with a separate GeV power law component. Here we show that such spectra can be understood in terms of magnetically dominated relativistic jets where a dissipative photosphere produces the prompt MeV emission, which is extended into the GeV range by inverse Compton scattering in the external shock, with possible contributions from a reverse shock as well. The bulk Lorentz factors required in these models are in the range of 300-600, and the MeV-GeV time delays arise naturally. In some cases an optical flash and a sub-dominant thermal component are also present.

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P. Veres, P. Mészáros. 2012-02-13. Single- and Two-Component GRB Spectra in the Fermi GBM-LAT Energy Range. https://doi.org/10.1088/0004-637x/755/1/12

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