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一个重复的快速无线电爆发源在球状星团
F Kirsten1,2, B Marcote3, K Nimmo4,5
1Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, Onsala, Sweden. kirsten@astron.nl.
Nature
|February 24, 2022
概括
局部化到球状星团的快速无线电爆发挑战了现有的模型. 这些发现表明FRB可能源于通过白矮星崩或在这些密集的恒星环境中形成的中子恒星.
科学领域:
- 天体物理学
- 无线电天文学
背景情况:
- 快速无线电爆发 (FRB) 是一个神秘的银河系外无线电短暂的源头.
- 虽然大多数FRB都是单一的事件,但也有一些重复的事件被观察到,导致了各种理论模型.
- 磁器经常被认为是FRB发射的来源.
研究的目的:
- 为了调查重复的快速无线电爆发20200120E的起源.
- 将现有FRB生成模型与新的观测数据进行测试.
主要方法:
- 使用射电望远镜观测的FRB 20200120E的定位.
- 该FRB源与附近的M81星系中的球状星团有关.
- 在一个老恒星群体中分析源位置的含义.
主要成果:
- FRB 20200120E被精确地定位在M81中的球状星团中,距离它的光学中心大约2个帕塞克.
- 球状星团中的位置,已知有古老的恒星群,与需要超新星的年轻磁星的模型相矛盾.
结论:
- 观察到的FRB位置挑战了基于核心崩超新星形成的年轻磁星的模型.
- 另一些模型认为,FRB 20200120E起源于高度磁化的中子星,通过白矮星积聚引起的崩或双星系统中紧的恒星合并而形成.
- 球状星团中紧的二进制星体的高频率支持这些替代的形成场景.
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