超新星遗迹激波加速粒子中的微观物理过程

Charged particles can be accelerated at the shocks of supernova remnants (SNRs), and the involved microphysics is the key to understand the particle acceleration and the magnetic amplification in SNRs, and the origin of the Galactic cosmic rays. Based on full particle simulation, this project, firstly, intends to investigate the acceleration process of the charged particles in the SNRs evolved in various environments, and the acceleration efficiency, the amplification of the disturbed magnetic field, the energy distribution of the accelerated particles can be achieved. Secondly, the heating of the particles in some SNRs are studied to interpret the detected electron/proton temperature ratio. Finally, the reacceleration of the cosmic rays by a non-relativistic shock is investigated, and the origin of the gamma-rays from those SNRs interacting with molecular clouds can be further enlightened.

带电粒子在超新星遗迹激波中被加速，其中发生的微观物理过程是理解遗迹中的粒子加速和磁场机制，以及银河系宇宙线粒子起源的关键。本项目将基于全粒子数值模拟方法，研究（1）在不同环境下带电粒子在超新星遗迹激波中的加速过程，获得粒子加速效率、扰动磁场激发、被加速粒子能谱分布特征；（2）激波中粒子加热机制，解释观测到的超新星遗迹中的电子、质子温度比；（3）宇宙线粒子在非相对论激波中的再加速过程，进一步探究来自超新星遗迹与分子云相互作用系统的伽马射线的起源本质。

超新星爆发时高速喷出的物质与周围介质相互作用形成非相对论激波，产生高能粒子并发出多波段辐射。超新星遗迹是银河系内重要的高能粒子源及伽马射线源，其辐射形态也往往各不相同。本项目基于数值模拟方法研究非相对论激波中带电粒子的加速以及超新星遗迹在非均匀介质中的演化，有助于进一步弄清楚银河系中高能宇宙线粒子的加速过程、高能伽马射线起源以及解释具有特殊形态的超新星遗迹产生机制。另外，我们也研究了近期观测到的部分100 TeV伽马射线源的起源，认为它们极可能产生于脉冲星风云。