Parkes observations for project P456 semester 2023APRS_06

The Parkes Pulsar Timing Array (PPTA) project has three primary goals: (a) detection of gravitational waves from astronomical sources, (b) establishment of a pulsar timescale, and (c) improvement of our understanding of Solar-system dynamics. We are now in an exciting regime where a signal detected in our (and other data sets) has the form expected for a gravitational wave background. We are therefore now attempting to confirm, or deny, this exciting result. With this proposal we aim to maintain our pre-eminent position in the field. Unlike most observing proposals, this is a continuing proposal for which the observations will continue to improve bounds on ultra-low-frequency gravitational waves until they are finally detected. Continued Parkes observations will remain valuable at least until the first stage of the SKA is able to improve on our sensitivity and observing cadence. Even after the gravitational wave background is detected we will want to continue observations in support of the nascent field of gravitational wave astronomy!

帕克斯脉冲星计时阵列（Parkes Pulsar Timing Array, PPTA）项目拥有三大核心目标：(a) 探测来自各类天文源的引力波；(b) 建立标准化脉冲星时标系统；(c) 深化对太阳系动力学机制的认知。当前我们正处于极具突破性的研究阶段：我们（及其他相关数据集）中探测到的信号，完全契合引力波背景的预期特征。因此我们正着手验证或推翻这一振奋人心的研究结果。本提案旨在维持我们在该领域的领先地位。与绝大多数观测提案不同，本提案属于持续性观测项目：观测工作将持续收紧超低频引力波的探测约束边界，直至最终成功探测到该信号。帕克斯望远镜的持续观测至少将保留其科学价值，直至平方公里阵列（Square Kilometre Array, SKA）的第一阶段项目能够显著提升我们的探测灵敏度与观测节律。即便引力波背景被成功探测之后，我们仍需持续开展观测，以支撑引力波天文学这一新兴领域的发展！