Parkes observations for project P1183 semester 2024OCTS_01

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年的监测工作，我们利用帕克斯（Parkes）望远镜完成57次观测、累计时长126.7小时，利用FAST望远镜完成101次观测、累计时长49.4小时，经分析确认FRB 20220529是一颗极端活跃的重复快速射电暴（fast radio burst, FRB）。该暴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。由于我们为帕克斯与FAST两台望远镜均安排了高频观测计划，近期我们在该源中首次探测到旋转测量量（rotation measure, RM）骤然耀变——这是人类首次在快速射电暴中观测到此类"RM耀变"事件，表明该源所处的环境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、探究暴活动与其他暴参数间的关联提供了独一无二的契机。若该周期性信号与"RM耀变"均得到进一步验证，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大量暴源信号，而帕克斯的宽频带接收机即使在暴源活动率较低的阶段，也保持了优异的暴源探测效率。值得注意的是，在此次RM耀变期间，帕克斯望远镜获得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关键依据。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。据此，我们同时提议使用帕克斯UWL接收机对FRB 20220529开展监测，采用高时间分辨率与全偏振观测模式。