Numerical simulation of the weak turbulence excited by a beam of electrons in the interplanetary plasma
Numerical simulation of the weak turbulence excited by a beam of electrons in the interplanetary plasma
复制标题
行星际等离子体中电子束激发弱湍流的数值模拟
DOI：
10.1007/bf00151988
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发表时间：
1982
期刊：
影响因子：
2.8
通讯作者：
R. Grognard
中科院分区：
文献类型：
--
作者：
R. Grognard
在通过ISEE-3航天器的电子流中在1 Au处测量的电子分布函数（Lin等人，1981）被用作程序的输入数据，该程序在一维模型中模拟快电子和等离子体波（“准线性”弛豫）之间的相互作用以及等离子体波散射背景离子。虽然计算出的等离子体波的光谱能量密度与电子流的共振激发低于扎哈罗夫的强湍流阈值，它是足够高的经历一个快速诱导散射的背景离子。由此产生的频谱集中在波矢量k = 0周围。一些简单的分析考虑表明，这一阶段必然会导致扎哈罗夫的阈值交叉，因此，这种间接激发强湍流似乎发挥了重要作用，在理解的朗缪尔湍流所产生的运动的快速电子束在行星际等离子体。
The electron distribution functions measured at 1 AU in an electron stream passing the ISEE-3 spacecraft (Lin et al., 1981) are used as input data to a programme which simulates in a one-dimensional model the interaction between fast electrons and plasma waves (‘quasi-linear’ relaxation) together with the plasma wave scattering off the background ions. While the computed spectral energy density of the plasma waves excited in resonance with the streaming of electrons is below Zakharov's threshold of strong turbulence, it is sufficiently high to undergo a fast induced scattering off the background ions. The resulting spectrum is concentrated around the wave vector k = 0. Some simple analytic considerations show that this stage leads necessarily to the crossing of Zakharov's threshold and therefore this indirect excitation of strong turbulence seems to play an essential role in understanding the Langmuir turbulence generated by the motion of fast electron beams in the interplanetary plasma.