从谱演化方面的信息探讨 GRB 061007 的暴周环境

GRB 061007是一个明亮的、长时标的伽玛射线暴（简称伽玛暴），其红移为1．261．一方面，Swift／XRT观测到的数据显示，此暴X射线波段的光变曲线呈现出单一幂率形态，且幂率指数αXRt=1．68±0．01．另一方面，经由Faulkes Telescope South（简写为FTS）提供的BVRi’多波段光学余辉数据，作者分析发现其各波段光变曲线的幂率指数αOptical均在1．6左右．拟合得到的2个波段幂率指数如此相近，也就意味着此暴的X射线波段和光学波段具有同一起源．作者通过分析X射线波段和光学波段的谱演化情况，探究GRB061007的暴周环境．分析的结果显示，X射线波段的谱指数JB没有演化，而光学波段的谱有向蓝端演化的趋势．根据其光学波段谱的演化趋势，推测此暴的暴周环境不是均匀介质，而应是星风环境．

Studying the environment of GRB 061007 from its spectral evolution

GRB 061007 is a bright and long gamma-ray burst （abbreviated as GRB） , with redshift z = 1. 261. On the one hand, the observed data by Swift/XRT shows that it has a remarkably simple power-law decay form with the falling slop （αXRT ： 168 ± 0. 01. On the other hand, the observed optical data by the Faulkes Telescope South （abbreviated as FTS） shows that it also has a remarkably simple power-law decay form with the falling slop C~optical ~ 1.60. The values obtained by data fitting of O~xRT and OtOpticaI are so similar that this means they have the same origin in the X-ray band and the optical band. We want to study the environment of GRB 061007 by ana- lyzing the spectral evolution of X-ray band and optical band. Our analysis shows that there is no evolution of the spectral index fl for X-ray band, while it has a blue shifting trend in optical band. Based on the above feature, we can speculate that GRB 061007 has a non-uniform environment, i. e. , the stellar wind environment.