Parkes observations for project P1172 semester 2022OCTS_13

PSR J1713+0747 is an extremely stable millisecond pulsar used in global pulsar timing array campaigns as a high priority pulsar because of its strong S/N, narrow profile and long-term observation history. In April 2021, the pulsar experienced a significant event related to a change in its magnetosphere, presented as an observable change in the pulsar’s profile. Since then, the pulsar has been slowly recovering and we wish to observe it with high cadence to allow us to create a detailed time-resolved series of variations in the MSPs profile, polarisation, and other properties. Under this proposal, we wish to probe the profile recovery on daily timescales (3 times per week with 2 day intervals in between), revealing additional short timescale behaviours, indicative of changes in the magnetosphere which are not available to other telescopes in the world, thanks to the Parkes UWL. This will also allow us to determine if the magnetosphere has returned to its original configuration or is settling into a new one. Understanding the recovery of this event is key for demonstrating that such pulsars are still viable clocks for use in gravitational wave studies, and in turn, provide us with new data on how the normally stable magnetosphere of this millisecond pulsar responds to an impulsive change in state.

PSR J1713+0747是一颗稳定性极强的毫秒脉冲星(millisecond pulsar)，因其高信噪比(S/N)、轮廓狭窄且具备长期观测历史，被列为全球脉冲星计时阵列(pulsar timing array, PTA)观测项目中的高优先级目标。2021年4月，该脉冲星发生了一起与其磁层(magnetosphere)变化相关的显著事件，表现为其脉冲轮廓出现可观测到的改变。自此之后，该脉冲星一直处于缓慢恢复阶段；为此我们计划以高频次开展观测，以构建一套详尽的时间分辨变化序列，涵盖该毫秒脉冲星的轮廓、偏振及其他特性。基于本观测提案，我们将以每日尺度对其轮廓恢复过程进行探测（每周观测3次，间隔2天），借此揭示此前未被捕捉到的短时标行为特征——这类特征可指示磁层发生了全球其他望远镜无法观测到的变化，这得益于Parkes UWL观测系统。本次观测还将帮助我们判断该脉冲星的磁层是否已回归初始构型，或是正逐渐稳定于全新的状态。厘清此次事件的恢复过程，对于证明这类脉冲星仍可作为引力波研究中的可靠时钟至关重要；同时也能为我们提供全新的数据，用以揭示这颗通常状态稳定的毫秒脉冲星的磁层是如何响应突发性状态变化的。