行星际结构与垂直无碰撞激波的相互作用

INTERACTION BETWEEN INTERPLANETARY STRUCTURE AND PERPENDICULAR COLLISIONLESS SHOCK

应用一维混合模拟方法数值研究了两种行星际结构──反向磁场和高密度等离子团与垂直无碰撞激波的相互作用．结果表明，随着激波上游区磁场的反向，下游区磁场将逐渐改变符号，且等离子体密度和速度分别呈现较强的湍动．激波上游和下游的物理量依然满足Rankine-Hugonoit关系．当高密度的等离子体团通过垂直无碰撞激波时，部分质子被激波反射，部分质子被加速并进入下游区域．由于质子速度分布为非Maxwell分布，在激波下游也激发出较强的湍动．

By using an one-dimension hybrid code, the intenation between two kinds ofinterpanemp structure-the reverse magnehc field and the plasmoid with highdensity, and perpendicular collisionless shock is studed numerically The results showthat as the magnetic field on upstream of a shock reverses the magnetic field indownstream changes its sign gradually and the stronger turbulence is formed in thedistributions of plasma density and velocity. The parameter in upstream anddownstream of the shock still satisfy the Rankine-Hugoniot relation. When theplasmoid with high plasma density passes through perpendicular collisioniess shock, apart of protons is reflected, the others are accelerated by shock and enter thedownstream. Since that the distribution of proton velocity in the downstream is innon-Maxwell distribution, the stronger turbulence is also excited.