标题： 斜激波：类空和类时 显示英文标题

标题： Oblique MHD shocks: space-like and time-like

摘要： 激波是物质中的不连续性，在研究天体物理情景中的等离子体行为以及重离子碰撞中具有相关性。 它们可以在相对论碰撞中产生锥形辐射，并且被认为是活动星系核和伽马射线暴中高能粒子加速的机制。 激波主要是流体动力学激波。 在磁场背景中，它们成为磁流体动力学(MHD)激波。 因此我们研究磁等离子体中的类空和类时激波不连续性。 激波会在等离子体中引起相变，这里假设是从强子到夸克的转变。 推导了激波处的MHD守恒条件。 对于给定的上游变量，求解下游速度和流动角度的守恒条件。 在不同的重子密度下求解激波条件。 对于类空激波，下游速度的各向异性是由于磁场引起的。 下游速度矢量相对于激波法线始终向下。 随着密度的增加，各向异性有所减小。 磁场对类时激波几乎没有影响。 下游流速中的微小各向异性是由加速效应引起的，这种效应将流体框架中的量转换到法线入射(NI)框架。 显示英文摘要

摘要： Shock waves constitute discontinuities in matter which are relevant in studying the plasma behaviour in astrophysical scenarios and in heavy-ion collision. They can produce conical emission in relativistic collisions and are also thought to be the mechanism behind the acceleration of energetic particles in active galactic nuclei and gamma ray bursts. The shocks are mostly hydrodynamic shocks. In a magnetic background they become magnetohydrodynamic (MHD) shocks. For that reason we study the space-like and time-like shock discontinuity in a magnetic plasma. The shocks induce a phase transition in the plasma, here assuming a transition from hadron to quarks. The MHD conservation conditions are derived across the shock. The conservation conditions are solved for downstream velocities and flow angles for given upstream variables. The shock conditions are solved at different baryon densities. For the space-like shocks the anisotropy in the downstream velocity arises due to the magnetic field. The downstream velocity vector always points downward with respect to the shock normal. With the increase in density the anisotropy is somewhat reduced. The magnetic field has effectively no effect on time-like shocks. The slight anisotropy in the downstream flow velocities is caused by the boosting that brings the quantities from the fluid frame to normal incidence (NI) frame.