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与银河磁星相关的快速无线电爆发
C D Bochenek1,2, V Ravi3, K V Belov4
1Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA. cbochenek@astro.caltech.edu.
Nature
|November 5, 2020
概括
快速无线电爆发 (FRB) 是一种神秘的宇宙信号. 研究人员检测到来自银河磁星的无线电爆发, SGR 1935+2154, 证实磁星是FRB的来源.
科学领域:
- 天文学与天体物理学
- 高能天体物理学
- 无线电天文学
背景情况:
- 快速无线电爆发 (FRB) 是一个持续数毫秒的来自银河系外的无线电短暂信号.
- 磁星是具有极强磁场的中子星,被认为是FRB的主要来源.
- 之前的观测没有直接证据将银河磁星与FRB现象联系起来.
研究的目的:
- 识别快速无线电爆发的来源.
- 调查磁星作为FRB原始体的可能性.
- 描述来自银河磁星的无线电爆发的特性.
主要方法:
- 从银河磁星SGR 1935+2154使用STARE2无线电阵列检测出持续数毫秒的无线电爆发,FRB 200428.
- 来自同一磁星的 X 射线爆发的观察.
- 对无线电爆发的流动性和能量进行分析,将其与脉冲星和银河系外FRB群体进行比较.
主要成果:
- 从银河磁星SGR 1935+2154中检测到一个持续数毫秒的无线电爆发 (FRB 200428).
- FRB 200428的能量明显高于以前的银河电波爆发,但与银河系外的FRB相美.
- 这次FRB事件与X射线爆发相吻合, 支持磁星相关的发射模型.
结论:
- 像SGR 1935+2154这样的活跃银河磁星可以产生快速无线电爆发 (FRB).
- 这一发现提供了强有力的证据表明磁星是银河系外FRB的来源.
- 这些发现支持涉及磁星爆发,闪电,同步子质或电磁脉冲的发射模型.
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