Parkes observations for project P938 semester 2016OCTS_BPSR_06

We propose a targeted, 357-hr search of two nearby galaxies with high star-formation rates (SFRs) for fast radio bursts (FRBs). The primary aim of this carefully designed experiment is to test the hypothesis that FRBs are correlated with SFR, and originate in the nearby Universe at typical distances of ~100 Mpc. This hypothesis is supported by leading models for FRBs that invoke extreme forms of young neutron-star emission, and by arguments based on signatures of FRB propagation. If the hypothesis is true, we expect ~20 FRB detections in our observations. In the case of a null result, we will show that FRBs are highly likely to originate at distances beyond ~175 Mpc. Our observations will also allow for the most sensitive search to date (by a factor of 30) for supergiant pulses from extragalactic analogues of the Crab pulsar. By using the 20cm Multibeam receiver, with the central beam pointed at the galaxies of interest, we will additionally perform a standard FRB search in all beams with an expected yield of one serendipitous event. Although we have no guarantee of a higher FRB detection rate than a truly blind survey, our experimental design ensures that we will finish with substantially greater insight into the FRB population.

本研究提出针对两个恒星形成率（star-formation rates, SFRs）较高的邻近星系开展时长357小时的靶向搜索，以搜寻快速射电暴（Fast Radio Bursts, FRBs）。本精心设计的实验核心目标为验证如下假说：快速射电暴与恒星形成率相关，且起源于邻近宇宙，典型距离约为100百万秒差距（Megaparsec, Mpc）。该假说得到了快速射电暴主流模型的支持——此类模型将快速射电暴归因于年轻中子星的极端辐射机制，同时也得到了基于快速射电暴传播特征的论证支撑。若该假说成立，我们预计本次观测将探测到约20次快速射电暴。若观测结果为零探测，我们将证明快速射电暴极有可能起源于距离超过约175百万秒差距的区域。本次观测还将开展迄今为止灵敏度最高、相较此前提升30倍的蟹状星云脉冲星河外类似体超巨脉冲搜索。我们将使用20厘米多波束接收机（20cm Multibeam Receiver），将中心波束对准目标星系，同时对所有波束开展标准快速射电暴搜索，预计将获得1次偶然探测事件。尽管我们无法保证本次实验的快速射电暴探测率高于纯盲巡天，但本实验设计确保我们最终将对快速射电暴族群获得更为深入的认知。