与超新星遗迹成协脉冲星的偏振观测研究

In the standard model of pulsar evolution, the pulsar was born in supernova explosions, so the faster-rotating young pulsas are considered to have close links with the supernova remnants. Compared with the normal interstellar medium, the dynamical evolution of the supernova remnant is more active. There are about 50 pulsars associated with supernova remnants in all known 1984 pulsars. Due to surrounded by a supernova remnant, the observed properties of the pulasr would certainly be affected by the dynamical evolution and magnetic field evolution of the supernova remnant. This project plans to use the Urumqi 25-m radio telescope to monitor 9 pulsars which are associated with supernova remnants in radio band, and to study the polarization properties and temporal variations of RM and DM of these pulsars. The main goal of the project is to study the variations with time of electron density and magnetic field of the supernova renmants.

在脉冲星演化的标准模型中，脉冲星诞生于超新星爆发中，因此旋转较快的年轻脉冲星被认为应与超新星遗迹有紧密的联系。与普通的星际介质相比，超新星遗迹的动力学演化更为活跃。在已发现的近2000颗脉冲星中，约有50颗与超新星遗迹成协。因被超新星遗迹所包围，所以脉冲星的观测性质肯定会受到超新星遗迹的动力学演化及磁场演化的影响。本项目计划利用乌鲁木齐25 米射电望远镜脉对蟹状星云脉冲星等9颗与超新星遗迹成协的脉冲星在射电波段进行监测，通过测量这些脉冲星射电辐射的偏振特性、法拉第旋转量（RM）和色散量（DM）随时间的变化，反推研究超新星遗迹的电子密度、磁场等随时间的演化关系。

到目前为止，有偏振观测数据的脉冲星在已知的2000多颗脉冲星中还是少数，尤其是高频的偏振数据则更少。脉冲星的偏振性质对于理解脉冲星的辐射机制、认识脉冲星辐射束的几何结构、辐射区高度及分布、脉冲星统计分布、探测星际介质、测量银河系磁场结构等方面都有重要的意义。本项目主要有以下两个方面的研究内容:（1）利用南山25米射电望远镜对100多颗脉冲星进行3年的长期监测，得到这些脉冲星的高信噪比的偏振轮廓，研究脉冲星的辐射机制；（2）测量并更新100多颗脉冲星的法拉第旋转量RM，并研究RM随时间及脉冲相位变化的性质及原因。