We report the discovery of a highly dispersed fast radio burst (FRB), FRB 181123, from an analysis of ∼1500 hr of drift scan survey data taken using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The pulse has three distinct emission components, which vary with frequency across our 1.0–1.5 GHz observing band. We measure the peak flux density to be >0.065 Jy and the corresponding fluence >0.2 Jy ms. Based on the observed dispersion measure of 1812 cm −3 pc, we infer a redshift of ∼1.9. From this, we estimate the peak luminosity and isotropic energy to be ≲2 × 10 43 erg s −1 and ≲2 × 10 40 erg, respectively. With only one FRB from the survey detected so far, our constraints on the event rate are limited. We derive a 95% confidence lower limit for the event rate of 900 FRBs per day for FRBs with fluences >0.025 Jy ms. We performed follow-up observations of the source with FAST for four hours and have not found a re...

中文翻译：

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快速漂移扫描调查中发现的快速无线电爆发

我们通过对使用五百米孔径球面射电望远镜（FAST）拍摄的约1500小时的漂移扫描调查数据进行分析，报告了高度分散的快速射电脉冲（FRB）181123的发现。脉冲具有三个不同的发射分量，它们随我们1.0–1.5 GHz观测频带内的频率而变化。我们测得的峰值通量密度> 0.065 Jy，相应的通量> 0.2 Jy ms。基于观察到的1812 cm -3 pc的色散测量，我们推断红移为1.9。据此，我们估计峰值发光度和各向同性能量分别为≲2×10 43 erg s -1和≲2×10 40 erg。到目前为止，从调查中仅检测到一个FRB，所以我们对事件发生率的限制是有限的。对于通量> 0.025 Jy ms的FRB，我们得出了每天900 FRB的事件发生率的95％置信下限。