Parkes observations for project P1183 semester 2025OCTS_03

After nearly three years of monitoring, comprising with the Parkes telescope and the FAST telescopes, FRB 20220529 is proven to be an extremely interesting repeater. It exhibits one of the longest activity durations and a potential ~200-day RM period. Due to frequent observations scheduled with both Parkes and FAST, an abrupt rotation measure (RM) flare has been observed 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 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.

经过近三年依托帕克斯望远镜（Parkes telescope）与500米口径球面射电望远镜（Five-hundred-meter Aperture Spherical radio Telescope, FAST）开展的监测工作，快速射电暴（Fast Radio Burst, FRB）20220529被证实为一颗极具科研价值的重复暴。该暴具备目前已知最长的活动持续时长之一，且疑似存在约200天的旋转量（Rotation Measure, RM）周期特征。得益于我们同时为帕克斯望远镜与FAST安排的高频观测计划，研究团队已在该源中观测到一次突发的旋转量耀斑。这是首次在快速射电暴（FRB）中观测到此类“旋转量耀斑”现象，表明该暴所处的环境中存在偶发的日冕物质抛射（Coronal Mass Ejection, CME）爆发活动。这为研究快速射电暴的爆发环境提供了独特契机，同时也可用于探究暴活动与其他暴参数之间的内在关联。若相关结论得到进一步验证，FRB 20220529的周期特征与“旋转量耀斑”现象将互为佐证，成为快速射电暴双星起源假说的关键确凿证据。在过往的分析工作中，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凭借更高的灵敏度帮助研究团队捕获了大量暴源信号，而帕克斯望远镜的宽带接收机即使在暴活动率较低的阶段，也能保持良好的暴源探测效率。值得注意的是，在此次旋转量耀斑事件期间，帕克斯望远镜观测到的两例高信噪比暴源信号，对我们理解旋转量的变化机制起到了关键支撑作用。为进一步开展FRB 20220529的相关研究，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UWL接收机（Parkes UWL receiver）对FRB 20220529开展监测，采用全极化观测模式以获取高时间分辨率的观测数据。