射电脉冲星巡天是探测获取更多脉冲星的重要途径.首先介绍了影响射电脉冲星巡天效率的因素,着重分析灵敏度和观测频率两个重要因素,并通过定义脉冲星探测率,简化对脉冲星巡天效率的估算.此外,总结了现有脉冲星巡天项目,利用Parkes多波束脉冲星及两次扩充巡天(Swinburne中纬度脉冲星巡天和Parkes高纬度脉冲星巡天)结果,采用包含时间演化的脉冲星分布模拟软件PsrPopPy,模拟得到脉冲星在银河系中分布的样本,并对近邻太阳系1kpc距离内的脉冲星数目进行了估算,获得了近邻脉冲星样本,可为脉冲星高能辐射对探测宇宙线正电子谱影响等研究提供可靠输入量.%Radio surveys are an important way to detect new pulsars. We first reviewed the main factors affecting sensitivities of pulsar searches in radio bands. These factors can be grouped into two categories. First, the instrumental factors include telescope size, observation frequency, observation bandwidth, integration time, sampling rate, digitization loss, and system temperature. Second, the intrinsic properties of pulsars include dispersion, period, and effective pulse width. We defined a generic detection rate (DR) that combine all these factors to be the number of pulsars detected with specific integration time per pointing. We summarized the results of all radio pulsar surveys. The most successful pulsar survey so far is Parkes multibeam pulsar survey (PKSMB), which detected 1086 normal pulsars. The PKSMB was expanded by two more surveys, namely, Parkes-Swinbume multibeam survey (PKSSW) and Parkes high-latitude multibeam pulsar survey (PKSHL), which in total detected 1377 normal pulsars. We utilized the software package PsrPopPy, which adopts a time evolution model of pulsar parameters, to simulate the Galactic pulsar distribution. The results of Parkes multi-beam pulsar survey and its two extensions were used as inputs of PsrPopPy to constrain the parameters of pulsar population. The tuned PsrPopPy provided a simulated Galactic pulsar population and its distribution in the Galaxy. We looked into the impacts of nearby neutron stars on Earth-based high energy physics experiments, particularly those based on positron detections. The excess of positron has been suggested as one evidence for the existence of dark matter. We examined the pulsar population of the solar neighborhood through the PsrPopPy simulations described above. Within 1kpc of the Sun, we predicted that there exist 600 pulsars, 13 of which can be Gamma ray pulsars. These high energy pulsars have potential of playing a significant role in the study of pulsar origins of the rising cosmic ray positron fraction.
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