Parkes observations for project P1183 semester 2025OCTS_23

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.

经过近三年的监测，依托帕克斯望远镜（Parkes telescope）与FAST望远镜开展的观测工作，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。该暴拥有迄今已知最长的活动持续时长之一，且存在约200天的旋转量度（rotation measure, RM）周期候选信号。得益于帕克斯望远镜与FAST望远镜的高频次观测计划，该源已被观测到一次突发的旋转量度耀斑。这是首次在快速射电暴中观测到此类“旋转量度耀斑”现象，表明该暴所处环境中存在偶发的日冕物质抛射（coronal mass ejection）活动。这为研究快速射电暴的爆发环境、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。若该周期性信号与“旋转量度耀斑”现象均得到证实，二者将互为佐证，成为快速射电暴双星起源假说的“确凿证据”。在过往的分析中，帕克斯望远镜与FAST望远镜的观测数据均发挥了关键作用。FAST望远镜的高灵敏度助力捕获了大量暴源信号，而帕克斯望远镜的宽带接收机即便在暴活动低发阶段，也能保持良好的暴源探测效率。值得注意的是，在此次旋转量度耀斑事件中，帕克斯望远镜观测到的两例高信噪比暴源信号，对理解旋转量度的变化起到了决定性作用。为进一步研究快速射电暴20220529，我们已计划每两周开展一次FAST望远镜常规观测，每次对该源进行20分钟的监测。因此，我们同时提议利用帕克斯UWL接收机对快速射电暴20220529开展监测，以确保获得高时间分辨率数据，并采用全偏振观测模式。