一个具有高能光谱成分的马射线爆发与同步子冲击模型不一致
M M González1, B L Dingus, Y Kaneko
1Physics Department, University of Wisconsin, Madison, Wisconsin 53706, USA. magda@whopper.lanl.gov
Nature
|August 15, 2003
概括
在1994年的马射线爆发 (GRB) 中观察到一种新的高能马射线成分. 这一发现挑战了标准模型,表明GRB中的新型粒子加速或质子-光子相互作用.
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
- 宇宙射线物理学 宇宙射线物理学
背景情况:
- 马射线爆发 (GRBs) 是宇宙中最有能量的现象.
- GRBs以光子 (30 keV MeV) 的形式发射了大部分能量,具有较低能量的后照.
- 标准模型将GRB辐射归因于冲击加速电子的同步子辐射.
研究的目的:
- 报告GRB中一个独特的高能光谱元件的观测.
- 为了调查GRBs标准同步子冲击模型的偏差.
主要方法:
- 1994年10月17日发生的马射线爆发的观测.
- 高能 (多MeV) 光子的光谱分析.
- 观察数据与标准相对论冲击模型的比较.
主要成果:
- 观察到一种独特的高能 (多MeV) 光谱成分,与低能马射线不同.
- 高能组件表现出较慢的流量衰变和更大的流动性.
- 这个组件遵循功率规律,达到~200 MeV (光子指数~-1).
结论:
- 观察到的高能元件挑战了GRBs的标准同步子冲击模型.
- 可能涉及到新的现象,例如替代的非热电子过程.
- 源头上的质子-光子相互作用是观察到的高能发射的潜在解释.
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