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arXiv · 1308.3236

Jet Luminosity from Neutrino-Dominated Accretion Flows in GRBs

Norita Kawanaka
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Abstract

A hyperaccretion disk around a stellar-mass black hole is a plausible model for the central engine that powers gamma-ray bursts (GRBs). We estimate the luminosity of a jet driven by magnetohydrodynamic processes such as the Blandford-Znajek (BZ) mechanism as a function of mass accretion rate, the black hole mass, and other accretion parameters. We show that the jet is most efficient when the accretion flow is cooled via optically-thin neutrino emission, and that its luminosity is much larger than the energy deposition rate through neutrino annihilation provided that the black hole is spinning rapidly enough. Also, we find a significant jump in the jet luminosity at the transition mass accretion rate between the advection dominated accretion flow (ADAF) regime and the neutrino-dominated accretion flow (NDAF) regime. This may cause the large variability observed in the prompt emission of GRBs.

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Norita Kawanaka. 2013-08-14. Jet Luminosity from Neutrino-Dominated Accretion Flows in GRBs. https://arxiv.org/abs/1308.3236

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