Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-11-13
Astronomy and Astrophysics
Astrophysics
28 pages, 12 figures, accepted by ApJ (March 2001 issue)
Scientific paper
10.1086/319734
There is growing observational evidence that gamma-ray bursts (GRBs) are powered by black holes accreting rapidly through a disk. The supernova-like outburst that accompanies some gamma-ray bursts suggest that some long-duration GRBs may be driven by the accretion of a rotating stellar core onto a central black hole. Such a system can be produced when a compact remnant spirals into the helium core of its binary companion. During the inspiral, orbital angular momentum is injected into the core. By the time the compact remnant reaches the center of the helium core, it too has gained angular momentum as well as mass, producing a rapidly accreting black hole (or neutron star) at the center of a rotating stellar core. In this paper, we use a 3-dimensional smooth particle hydrodynamics (SPH) code to follow such a merger process and make quantitative estimates of the initial mass and spin of the central compact remnant, as well as the angular momentum in the accreting helium core. From these results, we estimate GRB explosion energies. In all mergers, magnetically driven jets are expected to produce GRB explosions with energies above 10^{51} ergs. For neutrino-annihilation-driven explosions, the GRB energy increases dramatically with helium star mass: the merger of a 2 M_sun compact remnant with a 4 M_sun helium star only produces a 10^{47} ergs explosion in \sim 500 s whereas the merger of a 2 M_sun compact remnant with a 16 M_sun helium star produces a >10^{52} ergs explosion in \sim 65 s. (Abridged)
Fryer Chris L.
Zhang Weiqun
No associations
LandOfFree
The Merger of a Helium Star and a Black Hole: Gamma-Ray Bursts does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Merger of a Helium Star and a Black Hole: Gamma-Ray Bursts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Merger of a Helium Star and a Black Hole: Gamma-Ray Bursts will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-381128