Parkes observations for project P958 semester 2019OCTS_17

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——被定位到了遥远矮星系中的明亮射电星云（要么是年轻超新星遗迹，要么是脉冲星风云星云）。
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）开展的巡天探测已发现31次快速射电暴，其中5次被定位至红移值介于0.1至0.5之间的宿主星系。这些暴及其宿主星系与此前的重复暴截然不同，这暗示快速射电暴的种群或许存在二分性。然而近期研究发现，其中一台经角分级定位的ASKAP探测到的快速射电暴存在重复爆发现象。
本研究拟对该种群的快速射电暴展开重复爆发现象的搜寻与研究。我们将依托涵盖全面的样本库，以及针对精确定位暴的高密度监测计划，采用比此前探测阈值低60余倍的能流极限，对发生重复爆发的快速射电暴占比进行精准表征。针对存在重复爆发的暴，我们将借助独具特色的宽带宽观测数据，对快速射电暴辐射的主流理论模型进行检验。