2008/02/04 by Wei-Hua Lei, Wei‐Hua Lei, Ding-Xiong Wang +2 · 1 citation
Physics and Astronomy · #Accretion (finance) #Afterglow #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Atomic physics #Flare #Gamma-ray burst #Gamma-ray bursts and supernovae #Jet (fluid) #Physics #Rotational energy #astro-ph
paper · pdf · doi:10.1088/1009-9271/8/4/04
10 pages, 2 figures. Accepted by ChJAA
arxiv created 2008/02/04 · openalex publication_date 2008/08/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We propose a three-stage model with Blandford-Znajek (BZ) and hyperaccretion process to interpret the recent observations of early afterglows of Gamma-Ray Bursts (GRBs). In the first stage, the prompt GRB is powered by a rotating black hole (BH) invoking the BZ process. The second stage is a quiet stage, in which the BZ process is shut off, and the accretion onto the BH is depressed by the torque exerted by the magnetic coupling (MC) process. Part of the rotational energy transported by the MC process from the BH is stored in the disk as magnetic energy. In the third stage, the MC process is shut off when the magnetic energy in the disk accumulates and triggers magnetic instability. At this moment, the hyperaccretion process may set in, and the jet launched in this restarted central engine generates the observed X-ray flares. This model can account for the energies and timescales of GRBs with X-ray flares observed in early afterglows.