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来自GRB 221009A的延迟400 GeV光子以及对星系间磁场的影响
Zi-Qing Xia1, Yun Wang1, Qiang Yuan1,2
1Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, 210023, China.
Nature communications
|May 20, 2024
概括
大高空空气淋天文台检测到来自GRB 221009A的高能马射线. 费米探测到的一个延迟的400GeV光子表明了级联发射,而不是同步子自组.
科学领域:
- 高能天体物理学 高能天体物理学
- 马射线天文学 马射线天文学
背景情况:
- 在多个能量范围内观察到的马射线爆发 (GRB) 221009A事件.
- 大高空空中淋浴观测站 (LHAASO) 之前的观测检测到在触发2000秒内,0.213 TeV的辐射.
研究的目的:
- 为了分析费米大面积望远镜 (LAT) 从GRB 221009A中延迟检测400GeV光子.
- 调查导致这种延迟,高能光子的排放机制,并将其与替代模型进行比较.
主要方法:
- 来自费米大面积望远镜 (LAT) 的数据分析.
- 模拟星际磁场内的光子相互作用,以解释延迟发射.
- 对观察到的光子的级联发射与同步子自组电 (SSC) 的概率评估.
主要成果:
- 费米-LAT检测到来自GRB 221009A的400GeV光子,时间延迟0.4天,没有明显的低能发射.
- 延迟光子与源自大约10 TeV马射线的级联辐射一致,假设银河间磁场为~4x10^-17 G.
- 通过级联发射观测这种延迟光子的概率估计在0.3-1天内为2%,在0.3-250天内为20.5%.
结论:
- 级联发射是GRB 221009A延迟400GeV光子的一个最受欢迎的解释.
- 与级联场景相比,同步子自组 (SSC) 模型的偏好较小,概率比级联场景低3-30倍.
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