Evidence for isotropic emission in GRB991216

Abstract

The issue of the possible presence or absence of jets in GRBs is here re-examined for GRB991216. We compare and contrast our theoretically predicted afterglow luminosity in the 2-10 keV band for spherically symmetric versus jetted emission. At these wavelenghts the jetted emission can be excluded and data analysis confirms spherical symmetry. These theoretical fits are expected to be improved by the forthcoming data of the Swift mission.

6 pages, 1 figure, to appear on Advances in Space Research (in the Proceedings of the 35th COSPAR scientific assembly). New version to fit into the limit of 6 pages and to fix the format of the reference list

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• The Physics of Gamma-Ray Bursts
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Cited by in corpus (1)

• On the classification of GRBs and their occurrence rates