脉冲星搜索技术及FAST望远镜脉冲星搜索展望

Pulsar Searching Techniques and Their Applications to FAST Pulsar Search

分析现有的脉冲星搜索方法对于即将开展的FAST望远镜早期脉冲星搜索的可行性和必要性,尝试脉冲星搜索数据处理的软、硬件加速。回顾并总结了现有的脉冲星搜索方法和这些方法对应的发现,分析这些方法的特点。编写了基于PRESTO的并行数据处理程序。估计了使用显卡计算加速来完成单脉冲搜索的可行性和效率。编写的基于PRESTO的并行数据处理程序使得处理帕克斯望远镜多波束巡天的一个典型大小(100 MB)的文件的时间从约95 min缩短到短于10 min。使用显卡加速的单脉冲搜索实现了大约20倍的加速,数据处理时间短于获取观测数据的时间。对于使用望远镜早期观测数据进行脉冲星搜索而言,用于短轨道周期脉冲星搜索的相位调制搜索算法是没有必要的,用于搜索较长轨道周期的加速搜索算法也不十分必要,而用于长自转周期脉冲星搜索的快速折叠算法仅在需要搜索长自转周期的弱脉冲星时才需要使用。在数据处理过程中,软、硬件等方面可以加快数据处理的速度,可以使数据处理用时短于获取数据的时间。

We aim to see the feasibilities and necessities of applying current pulsar search methods to FAST pulsar search. We test pulsar search data processing with both software and hardware acceleration. We discuss methods used in current pulsar search, discoveries obtained by these methods and their characteristics. Based on PRESTO, we write scripts to run the pulsar search processing in a parallel manner. We evaluate the feasibilities and necessities of GPU acceleration in single pulse search. With the scripts, the time of processing a ParkesMulti-beam Pulsar Survey data file （with a typical size of 100 MB） has been shorten from approximately 95 minutes to less than 10 minutes. Our benchmark shows that the single pulse search in one file has been accelerated by 20 times. The single pulse search can be done in shorter time compared with the data aquisition process. Used to search for binary pulsars with short orbit periods, phase modulation search is not necessary for FAST pulsar search; similarly, used to search for binary pulsars with relative long orbit periods, the acceleration search is not important for FAST binary pulsar search and the fast folding algorithm is only necessary when searching for faint pulsars with long spin periods. For data processing, both software and hardware acceleration can and should be used to reduce time cost.