Relativistic Particle Transport and Acceleration in Structured Plasma Turbulence
Relativistic Particle Transport and Acceleration in Structured Plasma Turbulence
复制标题
DOI：
10.3847/1538-4357/ac5332
复制
发表时间：
2021-12
期刊：
影响因子：
--
通讯作者：
O. Pezzi;P. Blasi;W. Matthaeus
中科院分区：
文献类型：
--
作者：
O. Pezzi;P. Blasi;W. Matthaeus
讨论了相对论带电粒子在三维不可压缩MHD湍流中的能化现象及其运动的扩散特性。结果表明，湍流等离子体运动产生的随机电场使在模拟盒子中运动的实验粒子以随机方式加速，这是一个二级费米过程。这些粒子中有一小部分碰巧被困在大规模结构中，很可能是由于湍流中岛屿的相互作用而形成的。如果这些粒子的俯仰角满足某些条件，它们就会得到指数级的加速。我们详细地讨论了加速结构的特征和导致快速加速的物理过程。我们还评论了这些结果对现实天体物理湍流的适用性。
We discuss the phenomenon of energization of relativistic charged particles in three-dimensional incompressible MHD turbulence and the diffusive properties of the motion of the same particles. We show that the random electric field induced by turbulent plasma motion leads test particles moving in a simulated box to be accelerated in a stochastic way, a second-order Fermi process. A small fraction of these particles happen to be trapped in large-scale structures, most likely formed due to the interaction of islands in the turbulence. Such particles get accelerated exponentially, provided their pitch angle satisfies some conditions. We discuss at length the characterization of the accelerating structure and the physical processes responsible for rapid acceleration. We also comment on the applicability of the results to realistic astrophysical turbulence.