Parkes observations for project P970 semester 2018APRS_13

During the past 6 years, we at Parkes and collaborators at other radio telescopes have been remarkably successful at discovering millisecond pulsars (MSPs) associated with unidentified Fermi-LAT gamma-ray sources. Based on lessons learned, we here propose to carry out targeted searches with the new Ultra-wideband Low (UWL) receiver that will be installed next semester. The ultra-wide frequency coverage will enable us to detect MSPs with steep spectrum and avoid difficulties caused by interstellar scintillation and dispersive and scattering smearing. We propose to revisit highly ranked pulsar candidates that remain unidentified. Such a pilot survey will help us designing future searches of the coming 4FGL gamma-ray source catalog using the UWL. The overall time request is 23 hours on source, or 26 hours including overheads.过去六年间，我们帕克斯射电望远镜团队与其他射电望远镜的合作团队，在发现与未证认费米-LAT（Fermi-LAT）伽马射线源相关联的毫秒脉冲星（millisecond pulsars, MSPs）方面成果斐然。基于前期积累的研究经验，我们提议利用将于下学期安装的新型超宽带低频（Ultra-wideband Low, UWL）接收机开展靶向搜寻工作。该接收机的超宽频覆盖范围，将使我们能够探测具有陡谱的毫秒脉冲星，同时规避星际闪烁、色散展宽与散射展宽带来的观测难题。我们还提议对仍未得到证认的高优先级脉冲星候选体进行重新观测。此次先导巡天将为后续利用UWL接收机搜寻即将发布的4FGL伽马射线源目录中的源体提供重要参考。本次申请的总观测时长为源上观测23小时，含观测额外开销在内总计26小时。