Magnetized GRB outflow model:weak reverse shock emission and energy transfer timescale

摘要：

We show that the absence of the bright optical flashes in most Swift Gamma-Ray Burst(GRB)afterglows can beexplained,if the reverse shock region is magnetized with aσ~1,or the emission spectrum of the electrons accelerated inthe mildly magnetized(0.1<σ<1)reverse shock front is very soft,or the reverse shock of a non-magnetized ontflow issub-relativistic,where σ is the ratio of the magnetic energy flux to the particle energy flux．We also find that forσ》1,theenergy transfer between the magnetized ejecta and the forward shock may be too quick to account for the shallow declinephase that is well detected in many Swiyt GRB X-ray afterglows．

关键词： Gamma-ray bursts-radiation mechanisms nonthermal

作者: Yi-Zhong Fan

作者单位: Niels Bohr International Academy,Niels Bohr Institute,Copenhagen University,Blegdamsvej 17,DK-2100 Copenhagen.Denmark.Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210008,China.

会议类型: 国际会议

会议名称: 2008 NanJing Gamma-Ray Burst Conference(2008年伽马暴国际研讨会)

会议地点: 南京

会议语种:英文

页码: 159-164

在线出版日期: 2008-06-23（万方平台首次上网日期，不代表论文的发表时间）