van den Heuvel 2007 长暴的双星并合模型

主要内容:
认为一颗大质量氦主序星和一个近轨道致密星的并合可以产生长暴。

精彩摘抄:


文章信息:
Long Gamma-Ray Burst Progenitors: Boundary Conditions and Binary Models

Authors: E.P.J. van den Heuvel, S.-C. Yoon

(Submitted on 4 Apr 2007)

Abstract: The observed association of Long Gamma-Ray Bursts (LGRBs) with peculiar Type Ic supernovae gives support to Woosley`s collapsar/hypernova model, in which the GRB is produced by the collapse of the rapidly rotating core of a massive star to a black hole. The association of LGRBs with small star-forming galaxies suggests low-metallicity to be a condition for a massive star to evolve to the collapsar stage. Both completely-mixed single star models and binary star models are possible. In binary models the progenitor of the GRB is a massive helium star with a close companion. We find that tidal synchronization during core-helium burning is reached on a short timescale (less than a few millennia). However, the strong core-envelope coupling in the subsequent evolutionary stages is likely to rule out helium stars with main-sequence companions as progenitors of hypernovae/GRBs. On the other hand, helium stars in close binaries with a neutron-star or black-hole companion can, despite the strong core-envelope coupling in the post-helium burning phase, retain sufficient core angular momentum to produce a hypernova/GRB.

Comments:

8 pp., 2 figs, Proceedings of 5th Stromlo Symposium

Subjects:

Astrophysics (astro-ph)

Cite as:

arXiv:0704.0659v1 [astro-ph]