Excitation of nonlinear Alfvén waves by an ion beam in a plasma: 1. Right-hand polarized waves
Excitation of nonlinear Alfvén waves by an ion beam in a plasma: 1. Right-hand polarized waves
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等离子体中离子束激发非线性阿尔文波： 1. 右旋偏振波
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
M. Baine
中科院分区：
文献类型：
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作者：
V. Galinsky;V. Shevchenko;S. Ride;M. Baine
发展了冷离子束在太阳风等离子体中沿环境磁场运动时激发MHD波的自洽理论。利用解析和数值方法，我们研究了波幅指数增长的线性阶段，共振离子的俘获或俯仰角扩散引起的波幅饱和，以及等离子体非线性引起的波形陡化。用导数非线性薛定谔方程描述等离子体粒子的非线性输入，采用不完全数值模拟的混合方法研究共振粒子的强非线性运动。我们研究了波在正、负两个方向上传播的波能随磁场方向的时间行为，发现在所考虑的情况下，陡化剖面只对右手极化波产生。波变陡的物理机制是等离子体非线性产生的高次谐波。
A self-consistent theory of MHD wave excitation in the solar wind plasma by a cold ion beam moving along the ambient magnetic field is developed. Using analytical and numerical technics, we investigate the linear stage of the exponential growth of wave amplitudes, their saturation due to trapping or pitch angle diffusion of resonant ions and the steepening of the wave profile due to plasma nonlinearity. The derivative nonlinear Schrodinger equation was used to describe the nonlinear input of plasma particles, and a hybrid method of incomplete numerical simulation was used to investigate strongly nonlinear motion of resonant particles. We have studied the temporal behavior of wave energy for waves propagating in both positive and negative directions in relation to the magnetic field, directions and we have found that in cases under consideration the steepening profile developed only for right-hand polarized waves. The physical mechanism for wave steepening is higher harmonic generation due to plasma nonlinearity.