Parkes observations for project P1183 semester 2025APRS_15

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2年的监测，我们利用帕克斯望远镜（Parkes telescope）完成了57次观测、累计时长126.7小时，利用FAST望远镜完成了101次观测、累计时长49.4小时，据此确定FRB 20220529是一颗极为活跃的重复暴源。该源拥有目前已知最长的活动持续时长之一，并展现出潜在的周期信号。由于我们针对帕克斯望远镜与FAST均安排了高频观测计划，近期我们在该源中首次探测到突发旋转量（rotation measure, RM）耀斑——这是首次在快速射电暴（fast radio burst, FRB）中观测到此类‘RM耀斑’现象，表明该源所处的环境中偶尔会发生日冕物质抛射活动。这为研究快速射电暴的爆发环境提供了独特契机，也可用于探究暴源活动与其他爆发参数之间的关联。若该源的周期性与‘RM耀斑’现象均得到进一步证实，二者将相互印证，成为快速射电暴双星起源假说的‘确凿证据’。在我们此前的分析中，帕克斯望远镜与FAST的观测数据均发挥了不可或缺的作用：FAST更高的灵敏度帮助我们捕获了大量爆发事件，而帕克斯望远镜的宽频接收机即使在爆发率较低的阶段，也能保持良好的爆发探测效率。值得注意的是，在RM耀斑发生期间，帕克斯望远镜获取的两例高信噪比爆发事件，对于我们理解旋转量的变化起到了关键作用。为进一步开展对FRB 20220529的研究，我们已计划每两周开展一次FAST常规观测，每次对该源进行20分钟的监测。因此，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，以实现高时间分辨率观测，并开展全偏振观测。