Parkes observations for project P1345 semester 2025APRS_21

This proposal aims to constrain burst rates and spin down properties of a sample of new Rotating Radio Transients (RRATs) discovered with the ASKAP CRAFT Coherent upgrade (CRACO) system. Over the past 12-months of commissioning, CRACO discovered and precisely localised 15 new RRATs, characterised by their sporadic pulses with dispersion measures (DM) consistent with Galactic sources. We request 22.5h of Parkes time split into three 30min observations spanning 6-months for each target. This can help constrain periods and potentially phase-coherent timing solutions given that we already have arcsec-precision interferometric localisations. Our main science goals are: 1) to measure their burst rates, periods, and spin-down properties; 2) to assess their nulling fraction and intermittency; 3) to measure their polarimetric properties and constrain their emission mechanism; 4) to determine if the CRACO RRATs are fundamentally different from the known RRAT population. Some of these goals can be answered even with the detection of a limited number of pulses.

本研究提案旨在约束利用澳大利亚平方千米阵列探路者（ASKAP）的CRAFT相干升级系统（CRACO）发现的一批新旋转射电暂现源（Rotating Radio Transients, RRATs）的爆发率及自转减慢特性。在过去12个月的调试阶段中，CRACO已发现并精确定位了15颗新的旋转射电暂现源，这类源的特征为存在零星脉冲，且其色散量（dispersion measures, DM）与银河系内天体的色散量相符。我们申请了总计22.5小时的帕克斯（Parkes）望远镜观测时长，将每个目标的观测任务拆分为3次、每次30分钟的观测，分6个月完成。鉴于我们已获得角秒级精度的干涉测量定位结果，本次观测可帮助约束这些源的自转周期，并有望得到相位相干的计时解。我们的核心科学目标包括：1）测定这些源的爆发率、自转周期及自转减慢特性；2）评估其脉冲归零比例与间歇性爆发特征；3）测定其偏振特性并约束其辐射机制；4）探明CRACO发现的旋转射电暂现源是否在本质上区别于已知的旋转射电暂现源群体。即便仅探测到少量脉冲，部分科学目标也可得到解答。