Proga 2007 坍缩星模型的MHD模拟

主要内容:
可产生伽玛暴，以及可旋停然后产生X射线耀发。

精彩摘抄:


文章信息:

astro-ph/0701158 [abs, ps, pdf, other] :

Title: Magnetohydrodynamic simulations of the collapsar model for early and late evolution of gamma-ray bursts
Authors: Daniel Proga (UNLV)
Comments: 6 pages, to appear in Philosophical Transactions A

I present results from magnetohydrodynamic (MHD) simulations of a gaseous envelope collapsing onto a black hole. These results support the notion that the collapsar model is one of most promising scenarios to explain the huge release of energy in a matter of seconds associated with Gamma Ray Bursts (GRB). Additionally, the MHD simulations show that at late times, when the mass supply rate is expected to decrease, the region in the vicinity of the black hole can play an important role in determining the rate of accretion, its time behaviour, and ultimately the energy output. In particular, the magnetic flux accumulated around the black hole can repeatedly stop and then restart the energy release. As proposed by Proga and Zhang, the episode or episodes of reoccurring of accretion processes can correspond to X-ray flares discovered recently in a number of GRBs.