Time Evolution of Flares in GRB 130925a: Jet Precession in a Black Hole Accretion System

Abstract

GRB 130925A, composed of three gamma-ray emission episodes and a series of orderly flares, has been detected by Swif t, Fermi, Konus-W ind, and INTE-GRAL. If the third weakest gamma-ray episode can be considered as a giant flare, we find that after the second gamma-ray episode observed by INTEGRAL located at about 2000 s, there exists a positive relation between the time intervals of the adjacent flares and the time since the episode. We suggest that the second gamma-ray episode and its flares originate from the resumption of the accretion process due to the fragments from the collapsar falling back, such a relation may be related to a hyperaccretion disk around a precessed black hole (BH). We propose that the origin and time evolution of the flares, and the approximately symmetrical temporal structure and spectral evolution of the single flare, can be explained well by the jet precession model (Liu et al. 2010). In addition, the mass and spin of the BH can be constrained, which indicates a stellar-mass, fast rotating BH located in the center of GRB 130925A.

Fast Radio Bursts and Their Gamma-Ray or Radio Afterglows as Kerr–newman Black Hole Binaries

“…We proposed that charged and rotating BHs might be responsible for at least some FRBs when they discharge as a consequence of perturbations in their charged magnetospheres. Our model predicts that, if the right ambient conditions are present, the FRB might be followed by high-energy transients and a longer radio afterglow, similar to GRBs (e.g., Liu et al 2015a,b;Luo et al 2013;Hou et al 2014;Song et al 2015Song et al , 2016. In the case of BH binaries, if one of the holes is a KNBH surrounded by a magnetosphere, the FRB can be associated with a burst of GWs as the one recently detected by the LIGO and VIRGO Collaborations.…”

Central Engine of Late-Time X-Ray Flares With Internal Origin

“…Several mechanisms and models were proposed to explain the episodic phenomenon of X-ray flares King et al 2005;Dai et al 2006;Mészáros 2006;Perna et al 2006;Lazzati et al 2008;Lee et al 2009;Lazzati et al 2011;Yuan & Zhang 2012;Luo et al 2013;Hou et al 2014b. According to the internal origin of X-ray flares, the central engine that powers the prompt gamma-ray emission also powers the X-ray flares.…”

Neutrino-dominated accretion flows as the central engine of gamma-ray bursts

“…Hou et al (2014a) exhibited that a 86 +5.9 −9.4 s periodic oscillation may exist in the data from about 5300 s to about 6100 s in the bump of GRB 121027A using the stepwise filter correlation method (Gao et al 2012) and the LombScargle method (Scargle 1982), which can be interpreted by jet precession model (Liu et al 2010b). Hou et al (2014b) discovered that there is a remarkable time evolution in the data of the flares in GRB 130925A. It can be also explained by Equation (104) with reasonable initial BH mass and spin.…”

“…where J = a * GM 2 /c is the angular momentum of the BH, e ms and l ms are the specific energy and angular momentum corresponding to the marginally stable orbit radius r ms of the disk, i.e., (e.g., Novikov & Thorne 1973;Wu et al 2013;Hou et al 2014b)…”