Fermi Observations of high-energy gamma-ray emissions from GRB 080916C

Hiroyasu Tajima

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arXiv · 0907.0714

Fermi Observations of high-energy gamma-ray emissions from GRB 080916C

Hiroyasu Tajima

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Abstract

Observations of the long-duration Gamma-Ray Burst GRB 080916C by the Fermi Gamma-ray Burst Monitor and Large Area Telescope show that it has a single spectral form from 8 keV to 13.2 GeV. The E>100 MeV emission was ~5 s later than the E<1 MeV emission and lasted much longer even after photons with E<100 MeV became undetectable. The redshift from GROND of z~4.35 means that this GRB has the largest reported apparent isotropic gamma-ray energy release, E_{iso} ~ 8.8 x10^{54} ergs. It also sets a stringent lower limit on the GRB outflow Lorentz factor, Gamma_{min}~890, and limits the quantum gravity mass scale, M_{QG} > 1.3 x 10^{18} GeV/c^2.

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Hiroyasu Tajima. 2009-07-03. Fermi Observations of high-energy gamma-ray emissions from GRB 080916C. https://arxiv.org/abs/0907.0714

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