On the formation of wave packets in planetary foreshocks
On the formation of wave packets in planetary foreshocks
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DOI：
10.1029/96ja00926
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发表时间：
1996-07
影响因子：
--
通讯作者：
L. Muschietti;I. Roth;R. Ergun
中科院分区：
文献类型：
--
作者：
L. Muschietti;I. Roth;R. Ergun
研究了光束驱动朗缪尔波的动力学定位，以获得与电子前震环境相关的参数。对高能电子和朗缪尔波之间发生的相互作用进行了细胞内粒子模拟。结果表明，谐振电子中的非线性导致了从噪声中生长出来的数据包的形成。特征空间尺度取决于光束速度，并且对波幅的依赖性较弱。该机制发生在更短的时间尺度内，并且比由于体电子和离子而产生的经典非线性更小的振幅。例如，我们将结果应用于对地球和木星前震的观测。
Kinetic localization of beam-driven Langmuir waves is studied for parameters relevant to the electron foreshock environment. Particle-in-cell simulations of the interaction occurring between energetic electrons and Langmuir waves are performed. It is shown that the nonlinearities in the resonant electrons lead to the formation of packets growing out of the noise. The characteristic spatial scale depends upon the beam velocity and has a weak dependence on the wave amplitude. The mechanism takes place within shorter timescales and for smaller amplitudes than the classic nonlinearities due to bulk electrons and ions. As an example, we apply the results to observations made in the Earth and Jovian foreshocks.