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arXiv · astro-ph/0010440

Hyper- and suspended-accretion states of rotating black holes and the durations of gamma-ray bursts

Abstract

We analyze the temporal evolution of accretion onto rotating black holes subject to large-scale magnetic torques. Wind torques alone drive a disk towards collapse in a finite time $\sim t_{ff} E_k/E_B$, where $t_{ff}$ is the initial free-fall time and $E_k/E_B$ is the ratio of kinetic-to-poloidal magnetic energy. Additional spin-up torques from a rapidly rotating black hole can arrest the disk's inflow. We associate short/long gamma-ray bursts with hyperaccretion/suspended-accretion onto slowly/rapidly spinning black holes. This model predicts afterglow emission from short bursts, and may be tested by HETE-II.

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Maurice H. P. M. van Putten, Eve C. Ostriker. 2001-03-27. Hyper- and suspended-accretion states of rotating black holes and the durations of gamma-ray bursts. https://doi.org/10.1086/320253

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