来自马射线爆发GRB 130427A的明亮光学闪光和后照
W T Vestrand1, J A Wren, A Panaitescu
1Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA.
Science (New York, N.Y.)
|November 23, 2013
概括
来自马射线爆发 (GRBs) 的明亮光学闪光与高能马射线辐射相关. 这表明逆冲击辐射解释了早期的GRB后照,为恒星崩爆炸提供了洞察力.
科学领域:
- 天体物理学 天体物理学
- 高能天体物理学 高能天体物理学
- 观测宇宙学是一种观测性宇宙学.
背景情况:
- 马射线爆发 (GRBs) 是由巨大的恒星崩引起的强大的宇宙爆炸.
- 同时的光学和马射线发射为GRB物理提供了关键的见解.
- 了解GRBs的祖先系统和发射机制是天体物理学的一个关键目标.
研究的目的:
- 调查GRB 130427A.光学闪光和马射线辐射之间的关系.
- 为了确定负责观察到的光学和马射线信号的发射机制.
- 确定研究GRBs高能马射线辐射的最佳条件.
主要方法:
- 从GRB 130427A.的光学闪光和后照的观测.
- 分析光流和>100 MeV的马射线流之间的时间相关性.
- 在相对论喷射物中模拟冲击发射过程 (反向和前向冲击).
主要成果:
- 在最初的7000秒内,在光学和> 100 MeV的马射线流量之间观察到强烈的相关性.
- 这种相关性最好解释为相对论射出物与周围物质相撞的反冲击辐射.
- 后来,光学辐射被归因于一个向前冲击传播通过circumburst环境.
结论:
- 这项研究将光学后照与> 100 MeV的马射线辐射联系起来,支持冲击模型.
- 附近,早期峰值的光学后照被确定为研究千兆电子伏特到千兆电子伏特马射线辐射的主要目标.
- 这项研究增强了我们对控制马射线爆发及其相关现象的物理学的理解.
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