Kamble 2007 用wind加ISM解释GRB050319的余辉

主要内容:
GRB 050319的多波段余辉可以用wind加ISM的外部环境来解释，在0.02天的时候是转换时间。以此，也可以从侧面证实伽玛暴的大质量恒星坍缩模型。

精彩摘抄:


文章信息:

arXiv:0709.3561 [ps, pdf, other]

Title: Observations of the Optical Afterglow of GRB 050319 : Wind to ISM transition in view

Authors: Atish Kamble, L. Resmi, Kuntal Misra

Comments: 11 pages, 3 tables, 1 figures

Journal-ref: The Astrophysical Journal Letters, vol. 664, L5-L8, 2007 July 20

Subjects: Astrophysics (astro-ph)

The collapse of a massive star is believed to be the most probable progenitor of a long GRB. Such a star is expected to modify its environment by stellar wind. The effect of such a circum-stellar wind medium is expected to be seen in the evolution of a GRB afterglow, but has so far not been conclusively found. We claim that a signature of wind to constant density medium transition of circum-burst medium is visible in the afterglow of GRB 050319. Along with the optical observations of the afterglow of GRB 050319 we present a model for the multiband afterglow of GRB 050319. We show that the break seen in optical light curve at $\sim$ 0.02 day could be explained as being due to wind to constant density medium transition of circum-burst medium, in which case, to our knowledge, this could be the first ever detection of such a transition at any given frequency band. Detection of such a transition could also serve as a confirmation of massive star collapse scenario for GRB progenitors, independent of supernova signatures.