Levan Andrew J
Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK.
Philos Trans A Math Phys Eng Sci. 2007 May 15;365(1854):1315-21. doi: 10.1098/rsta.2006.1981.
Progress in understanding the nature of short gamma-ray bursts (GRBs) has been rapid since the discovery of the first afterglows in mid-2005. The emerging picture appears to be of short GRBs, which originate at moderate redshift (a few tenths) and appear in galaxies of all ages. This discovery has been used to argue for their origin in compact binary mergers. However, this population does not describe all short bursts. Here, I will present results of observations of several short GRBs, which challenge the conclusions drawn from the early observations. The observations show that some short GRBs originate in the very low redshift Universe (below 100Mpc), while some may also lie at redshifts comparable with the long GRBs (i.e. z>2). I will discuss the properties of these bursts and the implications they have for the progenitors of short GRBs.
自2005年年中首次发现短伽马射线暴(GRB)的余辉以来,在理解其本质方面取得了迅速进展。新出现的情况似乎是,短伽马射线暴起源于中等红移(十分之几),并出现在所有年龄段的星系中。这一发现被用来支持它们起源于致密双星合并的观点。然而,这一群体并不能描述所有的短伽马射线暴。在这里,我将展示对几个短伽马射线暴的观测结果,这些结果对早期观测得出的结论提出了挑战。观测结果表明,一些短伽马射线暴起源于极低红移的宇宙(低于100兆秒差距),而一些可能也处于与长伽马射线暴相当的红移(即z>2)。我将讨论这些伽马射线暴的性质以及它们对短伽马射线暴前身的影响。