论文标题
相对论的无碰撞冲击在不均匀的磁化等离子体中
Relativistic Collisionless Shocks in Inhomogeneous Magnetized Plasmas
论文作者
论文摘要
当传播到弱磁化的均匀介质中时，相对论无碰撞冲击与有效的颗粒加速有关。随着磁化的增加，颗粒加速度被抑制。我们证明，当上游带有动力学尺度不均匀性时，这种情况会发生变化，就像天体物理环境中一样。我们使用全运动模拟来研究磁化对等离子体中与上游密度扰动相互作用的相对论垂直冲击。对于$Δρ/ρ\ gtrsim 0.5 $的振幅，发现上游波动可散发冲击前线并在下游产生大规模的湍流剪切运动，而下游又能够加速颗粒。这可以使相对论磁性冲击作为天体物理系统（例如喷气机和增生磁盘）中的可行能量部位。大规模磁性结构的产生也对来自Blazars的极化信号具有重要意义。
Relativistic collisionless shocks are associated with efficient particle acceleration when propagating into weakly magnetized homogeneous media; as the magnetization increases, particle acceleration becomes suppressed. We demonstrate that this changes when the upstream carries kinetic-scale inhomogeneities, as is often the case in astrophysical environments. We use fully-kinetic simulations to study relativistic perpendicular shocks in magnetized pair plasmas interacting with upstream density perturbations. For amplitudes of $δρ/ρ\gtrsim 0.5$, the upstream fluctuations are found to corrugate the shock front and generate large-scale turbulent shear motions in the downstream, which in turn are capable of accelerating particles. This can revive relativistic magnetized shocks as viable energization sites in astrophysical systems, such as jets and accretion disks. The generation of large-scale magnetic structures also has important implications for polarization signals from blazars.
