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 toward collapse in a finite time ~tffEk/EB, where tff is the initial free-fall time and Ek/EB is the ratio of kinetic energy 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-2.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 2001
- DOI:
- 10.1086/320253
- arXiv:
- arXiv:astro-ph/0010440
- Bibcode:
- 2001ApJ...552L..31V
- Keywords:
-
- Black Hole Physics;
- Gamma Rays: Bursts;
- Gamma Rays: Theory;
- Astrophysics
- E-Print:
- accepted for publication in the ApJL