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arXiv 0811.4291astro-ph
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GRB 080129上升余辉前的一个强光学耀斑

A strong optical flare before the rising afterglow of GRB 080129

J. Greiner, T. Krühler, S. McBreen, M. Ajello, D. Giannos, R. Schwarz, S. Savaglio, A. Küpcü Yoldas, C. Clemens, A. Stefanescu, G. Sala, F. Bertoldi, G. Szokoly, S. Klose

摘要:

本文报道了GRB 080129在红移4.349处观测到的一个持续时间为40秒(静止帧)的光学耀斑。上升和衰减时间分别遵循指数为+12和-8的幂律,与反向冲击不一致,并且比ISM相互作用引起的变化快10倍$^5$。虽然过去已经看到过光学耀斑(例如GRB 990123,041219 B,060111 B和080319 B),但我们的观测首次不仅将光学耀斑分解为子分量,而且每分钟提供一次从光学到近红外的光谱能量分布。耀斑相对于GRB的延迟、它的光谱能量分布以及脉冲宽度的比值表明它是由GRB流出物\cite{liw08}中的剩余碰撞引起的。如果这种解释是正确的,并且可以通过更详细的建模或进一步GRB的观测来支持,延迟测量提供了一个独立的、确定流出物的洛伦兹因子的方法。

英文摘要:

We report on GROND observations of a 40 sec duration (rest-frame) optical flare from GRB 080129 at redshift 4.349. The rise- and decay time follow a power law with indices +12 and -8, respectively, inconsistent with a reverse shock and a factor 10$^5$ faster than variability caused by ISM interaction. While optical flares have been seen in the past (e.g. GRB 990123, 041219B, 060111B and 080319B), for the first time, our observations not only resolve the optical flare into sub-components, but also provide a spectral energy distribution from the optical to the near-infrared once every minute. The delay of the flare relative to the GRB, its spectral energy distribution as well as the ratio of pulse widths suggest it to arise from residual collisions in GRB outflows \cite{liw08}.If this interpretation is correct and can be supported by more detailed modelling or observation in further GRBs, the delay measurement provides an independent, determination of the Lorentz factor of the outflow.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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