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arXiv · 1311.5623

Fermi-LAT Observations of the Gamma-ray Burst GRB 130427A

LAT collaboration·GBM collaboration
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Abstract

The observations of the exceptionally bright gamma-ray burst (GRB) 130427A by the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope provide constraints on the nature of such unique astrophysical sources. GRB 130427A had the largest fluence, highest-energy photon (95 GeV), longest $γ$-ray duration (20 hours), and one of the largest isotropic energy releases ever observed from a GRB. Temporal and spectral analyses of GRB 130427A challenge the widely accepted model that the non-thermal high-energy emission in the afterglow phase of GRBs is synchrotron emission radiated by electrons accelerated at an external shock.

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LAT collaboration, GBM collaboration. 2013-12-09. Fermi-LAT Observations of the Gamma-ray Burst GRB 130427A. https://doi.org/10.1126/science.1242353

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