Parkes observations for project P1338 semester 2024OCTS_08

Fast radio bursts (FRBs) are millisecond-duration radio bursts of extragalactic origin. Since the discovery of the first FRB in the archival Parkes/Murriyang multibeam data, a broad dichotomy in population has emerged. Some FRBs have been seen to be repeating, while others are not, despite a significant amount of follow-up using different radio telescopes. The repeating FRB 20240114A was recently discovered by CHIME/FRB, which has been seen to have an exceptionally high burst activity. Such extreme burst activity has not been seen in any other source. The repeating FRBs, such as FRB 20240114A, provide an unparalleled window into their circumburst environment due to their repeating nature, which can be used to constrain possible progenitor models and test underlying emission mechanisms. The previous Parkes/Murriyang source follow-up has also revealed intriguing spectro-polarimetric properties, such as frequency-dependent evolution of burst central frequency or chromaticity, a possible activity window, significantly large circular polarisation (CP), and frequency-dependent CP. These properties hold the key towards understanding the circumburst environment of the FRBs, and test possible progenitor models. A large bandwidth instrument with reliable polarimetry has been critical in uncovering these properties. The ultra-wideband low (UWL) receiver on Parkes/Murriyang is ideally suited to explore the source's wideband spectro-temporal and polarimetric behaviour. We propose a campaign to regularly follow up FRB 20240114A to ascertain its long-term evolution of spectro-temporal properties.快速射电暴（Fast Radio Bursts, FRBs）是一类起源于河外空间、持续时长仅毫秒级的射电暴事件。自帕克尔斯/穆里扬射电望远镜（Parkes/Murriyang）的多波束存档数据中发现首例FRB以来，该类源的种群已显现出显著的二分性特征：尽管学界已利用多台不同射电望远镜开展了大量后续观测，但部分FRB被证实可重复爆发，另一部分则无重复爆发迹象。近期由CHIME/FRB合作组发现的重复暴FRB 20240114A，展现出异常高的爆发活跃度——这类极端爆发行为此前从未在其他射电暴源中被观测到。得益于可重复爆发的特性，这类重复FRB（例如FRB 20240114A）为研究其爆发周围环境提供了独一无二的窗口，可用于约束可能的前身星模型并检验其核心辐射机制。此前依托帕克尔斯/穆里扬射电望远镜开展的射电暴源后续观测，还揭示了诸多引人关注的光谱偏振特性：例如爆发中心频率的频率依赖演化（即色偏特性）、潜在的活跃爆发窗口、显著的高圆偏振度（circular polarisation, CP），以及圆偏振度的频率依赖行为。这些特性是破解FRBs爆发周围环境、验证各类前身星模型的关键所在。具备可靠偏振测量能力的大带宽观测仪器，是揭示这些特性的核心前提；而帕克尔斯/穆里扬射电望远镜搭载的超宽带低（UWL）接收机，恰好能够完美适配该源的宽带光谱时变与偏振特性研究。我们提议开展一项常态化后续观测计划，以追踪FRB 20240114A的光谱时变特性的长期演化过程。