附近的星系M82中的磁星巨型耀斑
Sandro Mereghetti1, Michela Rigoselli2, Ruben Salvaterra2
1INAF - Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano, Milano, Italy. sandro.mereghetti@inaf.it.
Nature
|April 24, 2024
概括
磁星的巨大耀斑是罕见的,强大的马射线爆发. 研究人员将M82中的GRB 231115A确定为磁星巨型耀斑,扩大了这些极端宇宙事件的样本.
科学领域:
- 高能天体物理学
- 中子星物理学
- 磁器研究
背景情况:
- 磁性巨型耀斑是来自具有超强磁场的年轻中子恒星发出的极其有能量,短暂的马射线.
- 观测银河系外巨型耀斑对于增加样本大小至关重要,但由于相似的亮度和距离,将它们与短玛射线爆发 (GRB) 区分开来是具有挑战性的.
- 之前的超银河磁性巨星火焰已经被提出, 但缺乏确定的证据.
研究的目的:
- 确定和确认一个超银河磁星巨型耀斑.
- 将观察到的事件与典型的短玛射线爆发 (GRB) 和其他天体物理现象区分开来.
- 用多波长的观测和没有引力波来进行明确的分类.
主要方法:
- 观测到的GRB 231115A,它发生在恒星星系M82中.
- 在检测后数小时内分析了GRB 231115A的光谱特性,爆发时间和X射线/光学对应物.
- 寻找重力波信号, 排除二进制聚变的起源.
主要成果:
- 在位置上,GRB 231115A与M82相吻合.
- 观察到的光谱特征,爆发时间和X射线和光学辐射的快速极限与磁星巨型耀斑一致.
- 没有检测到引力波信号,
结论:
- GRB 231115A被明确地确定为一个来自M82星系磁星的巨型耀斑.
- 这一发现显著扩大了观测到的银河系外磁星巨型耀斑的样本.
- 这种多面观测方法提供了一个强大的方法来识别未来的银河系外磁性巨型耀斑.
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