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arXiv · 0711.2277

Correlating prompt GRB photons with neutrinos

Abstract

It is standard in theoretical neutrino astrophysics to use a broken power law approximation, based on the Band function, to describe the average photon flux of the prompt emission of Gamma-Ray Bursts. We will show that this approximation overestimates the contribution of high energy gamma-rays (and underestimates low energy gamma-rays). As a consequence models that rely on this approximation overestimate neutrino event rate by a factor of approx 2 depending on Earth's column density in the direction of the GRB. Furthermore the characteristic energy of neutrinos that trigger a km^3 detector is typically 10^{16} eV, higher than previously predicted. We also provide a new broken power law approximation to the Band function and show that it properly represents the photon spectra.

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Ignacio Taboada, Michelangelo V. D'Agostino. 2007-11-14. Correlating prompt GRB photons with neutrinos. https://arxiv.org/abs/0711.2277

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