Parkes observations for project P957 semester 2017OCTS_BPSR_01

Pulse times of arrival are the key to any pulsar timing experiment, but the inferences we make depend critically on removing the effects of the interstellar medium. High-precision pulsar timing is reaching the limits of our ISM models and residuals effects may limit future goals, like the detection of gravitational waves. NICER, the newly-installed X-ray observatory on the International Space Station, provides the first opportunity to perform high-precision timing with X-rays, free from ISM effects. Radio telescopes still offer much greater precision, but NICER will allow us to carefully analyze ISM effects on a few pulsars. NICER will make weekly observations of PSR J1824-2452A, and we propose a high-cadence Parkes campaign to obtain contemporaneous radio TOAs. Since we know the "answer" from X-rays, we'll be able to test our ISM models and apply the results to all pulsar timing efforts.

脉冲到达时间（Times of Arrival，简称TOA）是所有脉冲星计时实验的核心，但我们所得出的推论在极大程度上依赖于去除星际介质（interstellar medium，简称ISM）的影响。高精度脉冲星计时技术已逼近现有ISM模型的极限，而残余效应可能会制约诸如引力波探测这类未来研究目标的实现。安装在国际空间站上的新型X射线天文台NICER，为我们提供了首个利用X射线开展高精度计时且不受ISM效应干扰的契机。射电望远镜仍能提供更高的计时精度，但NICER将使我们得以细致分析ISM对少量脉冲星的影响。NICER将对脉冲星PSR J1824-2452A开展每周一次的观测，同时我们提议开展高观测频次的帕克斯（Parkes）望远镜观测计划，以获取同步射电TOA数据。由于我们已掌握X射线观测得到的‘标准结果’，我们将能够验证现有ISM模型，并将所得结果应用于所有脉冲星计时研究工作中。