Parkes observations for project P456 semester 2023APRS_05

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.\r\n\r\nUnlike 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!

Parkes脉冲星计时阵列（Parkes Pulsar Timing Array, PPTA）项目有三大核心目标：（a）探测来自天文源的引力波（gravitational waves）；（b）建立脉冲星时标；（c）深化对太阳系动力学的理解。目前，我们正处于一个振奋人心的阶段——在我们（及其他数据集）中检测到的信号，其形式与引力波背景（gravitational wave background）的预期特征高度吻合。因此，我们正全力验证这一激动人心的结果是否成立。本提案旨在维持我们在该领域的领先地位。

与多数观测提案不同，本提案为持续性提案：观测将持续推进，不断收紧超低频率引力波的限制范围，直至最终探测到该信号。Parkes的持续观测至少在SKA第一阶段能够提升我们的灵敏度与观测节奏之前，都将保持其核心价值。即便引力波背景被成功探测，我们仍将继续观测，以支持新兴的引力波天文学领域发展！