一个快速的无线电爆发局部到一个巨大的星系
V Ravi1,2, M Catha3, L D'Addario4
1Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA. vikram@caltech.edu.
Nature
|July 3, 2019
概括
快速无线电爆发是一种强烈的银河系外无线电波. 我们定位了一个不重复的FRB到一个巨大的星系, 红移0.66,
科学领域:
- 天文学
- 天体物理学
- 宇宙学
背景情况:
- 快速无线电爆发是来自银河系外的强烈,持续数毫秒的无线电波.
- 它们的分散量表明来自银河系间和银河系外媒体的贡献.
- 虽然重复的FRB已经被定位,但不重复的FRB的主体在很大程度上仍未被确定.
研究的目的:
- 定位一个不重复的快速无线电爆发 (FRB190523),以确定其宿主星系和距离.
- 将一个不重复的FRB与已知的重复FRB (FRB 121102) 的宿主环境进行比较.
主要方法:
- 在发现FRB190523时使用高空间分辨率的干扰仪.
- 使用光谱分析确定宿主星系的红移.
主要成果:
- 定位FRB190523到一个巨大的星系在0.66的红移.
- 与FRB 121102的主星相比,宿主星系的质量明显更大 (1000倍),并且具有较低的特定恒星形成率 (100倍).
结论:
- 这项研究确定了非重复FRB的宿主星系和宇宙距离.
- 这些发现揭示了FRB祖先的环境多样性,表明不同的形成途径或进化阶段.
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