脉冲星周期跃变与辐射变化的关联

Radio rotation-powered pulsars are one type of Neutron Star, their rotation is generally stable. Nevertheless, observations show that 168 pulsars exhibit sudden increases in their spin frequency, known as glitches, which are believed to be caused by a rapid transfer of angular momentum from a neutron super-fluid of internal of star. On the other hand, more than 200 pulsars present obviously the emission variations which are pulse nulling, mode changing, sub-pulse drifting, and giant pulse. These phenomena are linked to the magnetosphere activities. Recently researches reveal that the variations of emission from a few pulsars are correlated with their rotations. The spin-down rates of intermittent pulsars are higher when they are on active mode, that than when they are on inactive mode. Lyne et al. (2010) show that the timing noises in six pulsars are correlated with the changes in the pulse shapes. Moreover, variations of emission from four pulsars are observed to associate with their glitches. All these evidences suggest that the activities of magnetosphere are linked to the pulsar rotations. This project will investigate the mechanism of the rotation instabilities in glitching pulsars, the variations of emission from a large sample of glitching pulsars, the interactive between variation of emission and spin-down. Such research aims to reveal the physics of pulsar internal and pulsar magnetosphere, the interactivities between internal and magnetosphere.

射电脉冲星，作为中子星的一类，其转动通常很稳定。然而，目前观测到已有168颗脉冲星发生自转频率增加的现象，也就是周期跃变，通常认为是脉冲星内部超流变化引起的。另一方面，二百多颗脉冲星的具有脉冲消零、模式变换、子脉冲漂移、巨脉冲等辐射特性，这些现象与脉冲星的磁层活动有关。最近的研究表明，越来越多脉冲星的辐射与脉冲星转动具有相关性。间歇脉冲星的在射电暴发态的自转减慢率比射电宁静态的自转减慢率大，Lyne et al. （2010）报告六颗脉冲星的自转减慢率变化与脉冲轮廓变化具有相关性。此外，有三颗射电脉冲星观测到射电辐射的变化与周期跃变事件有关。本项目拟大样本研究周期跃变脉冲星不稳定转动的物理过程、周期跃变脉冲星的辐射变化、周期跃变与辐射变化的关联，以揭示脉冲星的内部物理和磁层物理，以及脉冲星内部和磁层的相互作用。

最近的研究表明，越来越多脉冲星的辐射与脉冲星转动具有相关性。间歇脉冲星在射电暴发态的自转减慢率比射电宁静态的自转减慢率大，Lyne et al.（2010）报告六颗脉冲星的自转减慢率变化与脉冲轮廓变化具有相关性。此外，有三颗射电脉冲星观测到射电辐射的变化与周期跃变事件有关。本项目拟大样本研究周期跃变脉冲星不稳定转动的物理过程、周期跃变脉冲星的辐射变化、周期跃变与辐射变化的关联，以揭示脉冲星的内部物理和磁层物理，以及脉冲星内部和磁层的相互作用。本项目使用南山26米射电望远镜等国外内设备，得到了PSRs J1722−3632、J1852−0635、J1957+2831、Crab、Vela、J1023−5746、J2111+4606、J2229+6114 等脉冲星周期跃变的特征。揭示了PSR J1825−0935的准周期调制、Vela 脉冲星的巨微脉冲和子脉冲漂移、PSR B1237+25的强脉冲辐射特性。分析了J1539−5626、J1832−0827、J1847−0402和J1733−3716 自转参数的变化和辐射的变化，搜寻了自转与辐射的关联。研究了J0742−2822自转减慢率和脉冲轮廓半高全宽（W50）之间的相关性，探测到PSR J0738−4042自转变化和辐射变化相关性。