A second source of repeating fast radio bursts
A second source of repeating fast radio bursts
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DOI：
10.1038/s41586-018-0864-x
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发表时间：
2019-01
期刊：
影响因子：
64.8
通讯作者：
The Chimefrb Collaboration
中科院分区：
文献类型：
--
作者：
The Chimefrb Collaboration
重复快速射电爆发(FRB)源的发现，FRB/121102，消除了该来源涉及灾难性事件的模型。尽管最近有许多发现和后续研究，但到目前为止还没有检测到其他重复的FRB，这表明重复FRB在FRB群体中可能很少见。在这里，我们报告了从FRB-180814.J0422+73探测到的六个重复爆发，这是加拿大氢强度测绘实验(CHME)FRB项目在2018年7月和8月的预调试阶段探测到的13个FRB之一。这些重复爆发与其起源于天空中的单一位置是一致的，具有相同的弥散测量，约为每立方厘米189秒。这条视线追踪了大约两倍于预期的银河系自由电子柱密度，这意味着源红移的上限为0.1%，表明它与地球的距离至少比FRB(121102)近2倍。在一些重复爆发中，我们观察到亚脉冲频率结构、漂移和光谱变化，这让人想起FRB：121102，这表明类似的发射机制或传播效应。在最初几个CHAME/FRB发现中发现的第二个中继器表明，存在大量重复的FRB--CHAME/FRB和其他广视场、灵敏的射电望远镜将会发现。
The discovery of a repeating fast radio burst (FRB) source,, FRB 121102, eliminated models involving cataclysmic events for this source. No other repeating FRB has hitherto been detected despite many recent discoveries and follow-ups, –, suggesting that repeaters may be rare in the FRB population. Here we report the detection of six repeat bursts from FRB 180814.J0422+73, one of the 13 FRBs detected by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) FRB project during its pre-commissioning phase in July and August 2018. These repeat bursts are consistent with its origin from a single position on the sky, with the same dispersion measure, about 189 parsecs per cubic centimetre. This line of sight traces approximately twice the expected Milky Way column density of free electrons, which implies an upper limit on the source redshift of 0.1, showing it to be closer to Earth by a factor of at least 2 than FRB 121102. In some of the repeat bursts, we observe subpulse frequency structure, drifting and spectral variation reminiscent of that seen in FRB 121102,, suggesting similar emission mechanisms or propagation effects. This second repeater, found among the first few CHIME/FRB discoveries, suggests that there exists—and that CHIME/FRB and other wide-field, sensitive radio telescopes will find—a substantial population of repeating FRBs.