Parkes observations for project P991 semester 2019APRS_06

Finding radio pulsars orbiting near Sgr A* is a major goal of pulsar surveys with existing telescopes and future telescopes such as the Square Kilometer Array (SKA). The discovery of such pulsars will allow us to measure relativistic effects through timing of pulsars in tight orbits around Sgr A*, to characterise the distribution of dark matter near Sgr A*, to study the stellar population in the GC region and to probe the scattering region around Sgr A*. Although several surveys of the GC region have done, the Ultra-Wideband Low (UWL) receiver provides us a much wider frequency coverage with great sensitivity and therefore it is an excellent chance to revisit the GC region. At around 4GHz, a survey with UWL will achieve a sensitivity significantly higher than previous Parkes and Green Bank surveys, especially for pulsars with short spin periods and high dispersion measures.

寻找在人马座A*（Sgr A*）近旁轨道运行的射电脉冲星，是现有望远镜以及平方公里阵列（Square Kilometer Array, SKA）这类未来望远镜开展脉冲星巡天研究的核心目标之一。此类脉冲星的发现，将使我们能够通过对人马座A*周围紧密轨道中的脉冲星进行计时观测，测定相对论效应；还可用于刻画人马座A*附近暗物质的分布特征、研究银河中心（Galactic Center, GC）区域的恒星族群，并探究人马座A*周围的散射区域特性。尽管学界已针对银河中心区域开展过多项巡天观测，但超宽带低频（Ultra-Wideband Low, UWL）接收机拥有更宽的频段覆盖范围与优异的探测灵敏度，因此为我们重新观测银河中心区域提供了绝佳契机。在约4GHz频段下，搭载UWL接收机的巡天项目所能达到的探测灵敏度，将显著优于此前帕克斯（Parkes）与绿岸（Green Bank）望远镜开展的巡天工作，尤其针对短自旋周期、高色散量的脉冲星效果更为突出。