Parkes observations for project P1330 semester 2024APRS_03

Millisecond pulsars (MSPs) are created preferentially in globular clusters (GCs), compared to the Galactic disk, due to the large stellar density and the resulting interactions that occur within the clusters. Estimates have tens to hundreds of MSPs within these clusters. Furthermore, the leading hypothesis behind the gamma-ray emission from the GCs, detected by Fermi, is due to cluster MSPs. Thus, we observed three clusters, that were predicted to have tens of MSPs but did not have any detected, and found a highly accelerated binary MSP (NGC6316A) in NGC6316. Finding the first pulsar in a particular globular cluster is always the most challenging part as we have to search over the dispersion measure (DM) as well as period and acceleration. Our chances of finding more pulsars within the cluster have increased now that we know the DM of the cluster. We have a decent constraint on the orbital period of the binary but in order to fully constrain the orbital parameters and determine the type of companion star, we need subsequent observations. These subsequent observations will also be useful to search for more pulsars within the cluster. We are requesting 17 3 hour pointings to solve for the orbit of the binary pulsar and conduct a year-long timing campaign on the pulsar while searching for more pulsars.

毫秒脉冲星（Millisecond Pulsars，MSPs）相较于银盘（Galactic Disk），更倾向于在球状星团（Globular Clusters，GCs）中形成，这源于星团内部极高的恒星密度以及由此产生的各类恒星相互作用。
现有估算显示，此类球状星团中存在数十至数百颗毫秒脉冲星。
此外，费米（Fermi）望远镜探测到的球状星团伽马射线辐射，其主流假说认为辐射来源正是星团内的毫秒脉冲星。
据此，我们对三颗被预测拥有数十颗毫秒脉冲星但尚未有脉冲星被探测到的球状星团开展了观测，并在NGC 6316星团中发现了一颗高加速度双星毫秒脉冲星NGC6316A。
在单个球状星团中发现首颗脉冲星始终是最具挑战性的工作，因为我们需要同时对色散量（Dispersion Measure，DM）、脉冲周期以及加速度参数进行搜寻。
如今我们已获知该星团的色散量，这大幅提升了我们在星团内发现更多脉冲星的概率。
目前我们已对该双星系统的轨道周期得到了较为合理的约束，但要完全限定轨道参数并确定伴星的类型，仍需开展后续观测。
此类后续观测同样可用于在该星团内搜寻更多的脉冲星。
我们申请开展17次时长为3小时的指向观测，以求解该双星脉冲星的轨道参数，并针对该脉冲星开展为期一年的计时观测计划，同时搜寻星团内更多的脉冲星。