Simulation of collisionless electrostatic velocity‐shear‐driven instabilities

Abstract

The properties of electrostatic instabilities in velocity shear layers in collisionless plasmas are investigated by means of two‐dimensional particle simulations for the case where the ion gyroradius is comparable to the scale length of the velocity shear. For modes exactly perpendicular to the magnetic field, the Kelvin–Helmholtz instability dominates the evolution of the system producing eφ/Te≳1; the observed growth rates show no reduction compared to the hydromagnetic limit. To obtain this result for the case of negative shear (v0y’/Ωi<0), it is necessary to include the kinetic modifications to the structure of the shear layer equilibrium. For finite k∥ in the range 0

查看原文

分享

微信好友 朋友圈 QQ好友 复制链接

本刊更多论文

无碰撞静电速度-剪切驱动不稳定性的模拟

采用二维粒子模拟的方法研究了无碰撞等离子体中速度剪切层中静电不稳定性的性质，在这种情况下，离子的回旋半径与速度剪切的尺度长度相当。对于完全垂直于磁场的模式，开尔文-亥姆霍兹不稳定性主导了产生eφ/Te约1的系统的演化;观察到的生长率与水磁极限相比没有减少。为了得到负剪切(v0y ' /Ωi<0)情况下的这一结果，有必要将剪切层平衡结构的动力学修饰包括在内。对于k∥在0 2×10−3。

本文章由计算机程序翻译，如有差异，请以英文原文为准。