一个单一的快速无线电爆发局部到一个巨大的星系在宇宙距离
K W Bannister1, A T Deller2, C Phillips3
1Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia. keith.bannister@csiro.au rshannon@swin.edu.au.
Science (New York, N.Y.)
|June 29, 2019
概括
我们准确地定位了一个不重复的快速无线电爆发 (FRB) 到一个距离中心4千帕塞克的星系. 这个FRB提供了对星系间介质和宇宙网络的新见解.
科学领域:
- 天文学与天体物理学
- 宇宙学
背景情况:
- 快速无线电爆发是来自银河系外的神秘,强烈的无线电辐射.
- 虽然一些FRB重复,但大多数是单一事件,使得它们的确切起源难以确定.
- 之前的非重复FRB定位不足以确定它们的主星系.
研究的目的:
- 为了实现单脉冲快速无线电爆发 (FRB) 的精确干扰度定位.
- 为了研究FRB及其宿主星系的特性.
- 评估FRB作为星系间介质的探测器的潜力.
主要方法:
- 使用干涉测量来高精度定位单脉冲FRB 180924.
- 确定了爆炸相对于发光的主星系的位置, 红移0.3214.
- 分析了视线上的集成电子柱密度.
主要成果:
- 定位FRB180924在距主星系中心4千帕塞克的位置.
- 证实FRB180924是一个不重复的爆发.
- 与此前局部化的FRB相比,该FRB及其宿主有着不同的特性.
- 发现集成电子柱密度与星系间介质模型一致.
结论:
- 单脉冲FRB可以很准确地定位,从而能够识别宿主星系.
- FRB 180924及其环境与其他局部FRB有很大的不同,突出显示了FRB的多样性.
- 它们是宇宙网络中的有效探测器.
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