Parkes observations for project P1183 semester 2024OCTS_10

After nearly two years of monitoring, comprising 126.7 hours over 57 observations with the Parkes telescope and 49.4 hours across 101 observations with the FAST telescopes, we have determined that FRB 20220529 is an extremely active repeater. It exhibits one of the longest activity durations and a potential period. Due to frequent observations scheduled with both Parkes and FAST, we recently observed an abrupt rotation measure (RM) flare in this source. This is the first detection of such an ``RM flare'' in a fast radio burst (FRB), suggesting that the source is in an environment with occasionally erupting coronal mass ejection. This presents a unique opportunity to study the eruption environment of FRBs and investigate the relation between burst activity and other burst parameters. If confirmed, the periodicity and the ``RM flare'' of FRB 20220529 would corroborate each other and become a ``smoking gun'' of the binary origin of FRB. In our previous analysis, both Parkes and FAST observations have proven essential. While FAST's higher sensitivity has enabled the capture of many bursts, Parkes' wideband receiver has provided a good burst detection rate even during low-rate phases. Notably, during the RM flare, two high signal-to-noise ratio bursts from Parkes have been crucial in understanding the RM variations. To further investigate FRB 20220529, we have scheduled regular FAST observations every fortnight, monitoring the source for 20 minutes each time. Therefore, we also propose to monitor FRB 20220529 using the Parkes UWL receiver, ensuring high-time resolution and employing full-polarization observations.

经过近两年的监测工作，我们依托帕克斯（Parkes）望远镜完成了57次观测，累计时长126.7小时；同时使用FAST望远镜开展了101次观测，累计时长49.4小时，由此确定FRB 20220529是一颗极为活跃的重复快速射电暴（fast radio burst, FRB）。该暴具备迄今已知最长的活动持续时长之一，并展现出潜在的周期性特征。得益于帕克斯与FAST的密集观测计划，我们近期首次在该源中探测到旋转测量量（rotation measure, RM）耀发现象——这是人类首次在快速射电暴中观测到此类“RM耀变”事件，暗示其所处环境中存在偶发的日冕物质抛射活动。这为研究快速射电暴的爆发环境，以及探究暴活动与其他暴参数之间的关联提供了独一无二的契机。若该结论得到证实，FRB 20220529的周期性与“RM耀变”将互为佐证，成为快速射电暴双星起源假说的决定性证据。在我们此前的分析中，帕克斯与FAST的观测数据均发挥了不可或缺的作用：FAST凭借更高的灵敏度捕捉到了大量暴源信号，而帕克斯的宽波段接收机即使在暴发率较低的阶段，也能维持良好的暴源探测效率。尤为关键的是，在此次RM耀变期间，帕克斯望远镜获取的两例高信噪比暴源信号，为我们理解旋转测量量的变化提供了核心支撑。为进一步开展FRB 20220529的相关研究，我们已规划每两周开展一次FAST常规观测，每次对该源进行20分钟的监测。据此，我们同时提议使用帕克斯望远镜的UWL接收机对FRB 20220529开展监测，采用全极化观测模式以保障高时间分辨率。