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arXiv · 1306.6690

Neutrino-cooled Accretion Model with Magnetic Coupling for X-ray Flares in GRBs

Yang Luo·Wei-Min Gu·Tong Liu·Ju-Fu Lu
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Abstract

The neutrino-cooled accretion disk, which was proposed to work as the central engine of gamma-ray bursts, encounters difficulty in interpreting the X-ray flares after the prompt gamma-ray emission. In this paper, the magnetic coupling between the inner disk and the central black hole is taken into consideration. For mass accretion rates around $0.001 \sim 0.1 M_{\sun} s^{-1}$, our results show that the luminosity of neutrino annihilation can be significantly enhanced due to the coupling effects. As a consequence, after the gamma-ray emission, a remnant disk with mass $M_{disk} \la 0.5 M_{\sun}$ may power most of the observed X-ray flares with the rest frame duration less than 100 seconds. In addition, a comparison between the magnetic coupling process and the Blandford-Znajek mechanism is shown on the extraction of black hole rotational energy.

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Yang Luo, Wei-Min Gu, Tong Liu, Ju-Fu Lu. 2013-06-28. Neutrino-cooled Accretion Model with Magnetic Coupling for X-ray Flares in GRBs. https://doi.org/10.1088/0004-637x/773/2/142

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