Parkes observations for project P958 semester 2019OCTS_76

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）至今引发的疑问远多于已解答的谜题。直至去年，学界仅确认一例可重复的快速射电暴，其定位结果显示它位于一个遥远矮星系中的明亮射电星云（年轻超新星遗迹或脉冲星风云星云）内。
过去两年间，利用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例快速射电暴，其中5例被定位至红移值介于0.1至0.5之间的宿主星系。这些暴源及其宿主星系与此前已知的重复暴源特征差异显著，暗示该类暴源群体或存在二分性。然而近期研究发现，一例经角分级定位的ASKAP探测FRB同样具备重复爆发特性。
本研究拟针对该FRB群体开展重复爆发特征的搜寻与研究工作。我们将依托完备的样本集与针对高精度定位暴源的密集监测计划，以比此前探测阈值低60倍以上的能流极限，定量表征可重复爆发的暴源占比。针对重复爆发的FRB，我们将利用独特的宽波段观测数据，对主流的暴源辐射模型开展验证测试。