Parkes observations for project P958 semester 2019OCTS_09

Fast radio bursts (FRBs) continue to raise more questions than they answer. Until last year, only one burst – the only one known to repeat - had been localized to a bright radio nebula (either a young supernova remnant or pulsar wind nebulae) in a distant dwarf galaxy. \r\nOver the last two year searches with the Australian Square Kilometre Array Pathfinder (ASKAP) have detected 31 bursts, five of which have been localised to host galaxies at redshifts ranging from 0.1 to 0.5. These bursts and their hosts are very unlike the repeater, suggesting there may be a dichotomy in the population. However one of the arcminute-localised ASKAP FRBs has recently been found to repeat.\r\n Here we propose to search and study repetitions in this FRB population. Our comprehensive sample and a dense monitoring campaign of well localised bursts, at a fluence limit more than 60 times lower than that of their detections to characterise the fraction of bursts that repeat. For bursts that repeat the unique wide bandwidth observations will be used to test leading models of burst emission.

快速射电暴（Fast radio bursts, FRBs）所引发的疑问始终多于其所能解答的问题。直至去年，仅有一种暴——也是目前已知唯一会重复爆发的暴——被定位于遥远矮星系中的明亮射电星云（即年轻超新星遗迹或脉冲星风云星云）。
过去两年间，借助澳大利亚平方千米阵探路者（Australian Square Kilometre Array Pathfinder, ASKAP）开展的巡天探测共发现31次快速射电暴，其中5次被定位于红移值介于0.1至0.5之间的宿主星系。此类暴体及其宿主星系与此前发现的重复暴体差异显著，暗示快速射电暴种群或存在二分特性。然而近期研究发现，其中一例经角分级定位的ASKAP快速射电暴同样存在重复爆发现象。
本研究拟针对该快速射电暴群体开展重复爆发现象的搜寻与研究。我们将依托完整的观测样本，以及针对精确定位暴体的密集监测计划，在比此前探测阈值低60余倍的能流极限下，定量表征发生重复爆发的快速射电暴占比。
对于存在重复爆发的暴体，我们将借助独具特色的宽带宽观测数据，检验当前主流的暴体辐射模型。