Parkes observations for project P958 semester 2019OCTS_02

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快速射电暴——被定位于遥远矮星系中的明亮射电星云（要么为年轻超新星遗迹，要么是脉冲星风云）。 过去两年间，利用澳大利亚平方千米阵列探路者（Australian Square Kilometre Array Pathfinder, ASKAP）开展的巡天探测已捕获31次射电暴，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。这些射电暴及其宿主星系与该重复暴的特征差异显著，暗示快速射电暴的种群或存在二分性。不过，近期研究发现，其中一批经角分级定位的ASKAP探测快速射电暴存在重复爆发现象。 本文拟针对该快速射电暴种群开展重复爆发特征的搜寻与研究。我们将依托完备的样本集，对定位精度较高的射电暴实施高密度监测，监测的积分通量极限较此前探测阈值低60倍以上，以量化统计发生重复爆发的射电暴占比。 针对存在重复爆发的射电暴，我们将利用独有的宽带宽观测数据，对当前主流的射电暴辐射模型开展验证。