Oral Presentation

Neutrino-cooled Accretion Model with Magnetic Coupling for X-Ray Flares in Gamma-Ray Bursts

Author(s): Weimin Gu (Xiamen University)

Presenter: Weimin Gu (Xiamen University)

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 our work,the magnetic coupling between the inner disk and the central black hole is taken into consideration.For mass accretion rates around 0.001~0.1 Msun/s, our results show that the luminosity of neutrino annihilationcan be significantly enhanced due to the coupling effects. As a consequence, after the gamma-ray emission,a remnant disk with mass M_disk < 0.5 Msun may power most of the observed X-ray flares with the rest frame durationless 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.