Parkes observations for project P958 semester 2019OCTS_74

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）所引发的疑问远多于其已解答的问题。直至去年，仅有一种暴——也是目前已知唯一会重复爆发的暴——被定位到遥远矮星系中的明亮射电星云（要么为年轻超新星遗迹，要么为脉冲星风云）内。
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次已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发现的重复暴存在显著差异，暗示该暴群体可能存在二分性。然而近期研究发现，其中一例经角分定位的ASKAP快速射电暴存在重复爆发现象。
本文拟对该快速射电暴群体开展重复爆发现象的搜寻与研究。我们将依托完整的样本库，针对已精确定位的暴源实施高密度监测计划，该计划的流量密度探测极限较此前的探测结果低60倍以上，以此精准表征发生重复爆发的暴源占比。对于存在重复爆发的暴源，我们将借助独特的宽带宽观测数据，检验当前主流的暴源辐射模型。