中国天眼捕捉到快速射电暴多次重复爆发

China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST) has detected a repeating fast radio burst (FRB) -- mysterious radio signals from outer space -- for the first time, Science and Technology Daily reported.

据《科技日报》报道，中国500米口径球面射电望远镜（FAST）首次探测到快速射电暴（FRB）多次重复爆发，FRB这种神秘的无线电信号来自于宇宙的深处。

Scientists on the FAST project with the National Astronomical Observatories of China, part of the Chinese Academy of Sciences, revealed the news last Wednesday.

中国科学院国家天文台FAST项目的科学家在上周三发布了这一消息。

The FRB originated some three billion light years away from Earth. Interference factors including aircraft and satellites have been eliminated and cross validation is being carried out, the scientists said.

科学家称，这个“宇宙深处的神秘射电信号”发射源距离地球约30亿光年，目前已排除了飞机和卫星等干扰因素，后续交叉验证正在进行之中。

FRB has since become one of the hottest topics in astronomy. It was not until 2007 when the first FRB was discovered by humans. Fewer than 100 FRBs have been detected internationally to date.

作为近年来天文学界的热门话题，直到2007年人们才第一次探测到快速射电暴。截至目前，全世界探测到的快速射电暴不到100次。

There is still no cohesive explanation for the origin of FRB in the international scientific community at present. FRBs mostly only appear once, which makes them very hard to track.

迄今为止，国际科学界尚没有关于快速射电暴起源的合理解释。通常情况下，快速射电暴出现一次便再无踪迹，从而导致追踪工作非常困难。

The FRB detected by FAST's real-time detection terminal, however, is one that has been observed before, said Zhang Xinxin, an assistant engineer with the NAOC.

国家天文台助理工程师张馨心表示，FAST这次使用实时探测终端探测到的快速射电暴之前也曾探测到过。

Known as FRB121102, it was first discovered in 2012 and found to repeat in 2015. Analysis of data later located the source of the signal coming from a dwarf galaxy three billion light years away.

该射电暴被命名为FRB121102，2012年首次发现，2015年捕捉到其重复爆发。通过随后的数据分析，其信号源位于一个距离地球约30亿光年的矮星系中。

The first pulse from FRB121102 was spotted by FAST on Aug 30. After this, the telescope recorded dozens of pulses from the FRB over the course of days. On Sept 3 alone, more than 20 pulses were detected.

8月30日上午，FAST首次实时探测到来自FRB121102的脉冲。此后，连续多日，FAST每天探测到了数十个来自FRB121102的脉冲，仅在9月3日当天就探测到20多个。

The number of enigmatic bursts detected so far is too small to draw any conclusions, Zhang said.

张馨心表示，目前探测到的快速射电暴太少，尚且难以得出任何结论。

FAST, the world's largest single-dish radio telescope, has a certain edge in detecting repeated FRBs. This is because the 19-beam receiver installed on FAST, covering frequency ranges of 1.05 -- 1.45 GHz, is very sensitive to radio signals, Zhang said.

张馨心称，FAST是世界上最大的单口径射电望远镜，非常适合重复性射电暴的搜寻。因为其目前安装使用的19波束接收机覆盖1.05GHz—1.45GHz频段，对无线电信号有很高的灵敏度。