Non-linear effects in electron plasmas

Author:

Abstract

In this investigation of non-linear effects in electron plasmas, the complications of finite boundaries, external fields, non-zero temperature, multi-stream flow and collisions are ignored. Non-linear effects are studied by a perturbation process, the method of variation of parameters, which yields the dominant effects in weakly excited plasmas. The effects fall into three groups: the excitation of harmonics; coherent interaction; and incoherent interaction. 'Coherent’ interaction represents all effects which do not result in a redistribution of energy in wave-number space. Such effects, which arise also in the familiar theory of electron plasmas at non-zero temperature, may be summarized by a dispersion relation. The principal aim of this work has been to study the incoherent inter­action which is responsible for spectral decay, that is for the redistribution of energy in wave-number space—the breakdown of organized large-scale motion into disorganized small-scale motion. It is found that, to a certain stage of approximation, purely one-dimensional spectra are unique in exhibiting no spectral decay. The decay of a certain spectrum which is almost one-dimensional may be followed analytically and leads to the following result: plasma oscillations which initially have depth of modulation D and are collimated within an angle ε tend to isotropy in (4 ε D 2 ) -1 plasma periods. This effect may be attributed to a ‘plasma viscosity’ with coefficient ½ ω -1 P < v 2 >. The incoherent interaction between plasma oscillations and transverse (non-divergent) motion may be interpreted as viscosity or as a scattering process, depending upon the relative scales of the components. The effects studied in this paper may be interpreted as the result of collisions between plasmons; this interpretation illuminates the problem of spectral decay and suggests that the rate of decay of a one-dimensional spectrum is proportional to D 4 . Estimates of the damping of plasma oscillations by the mechanism of spectral decay are compared with the results of certain experiments.

Publisher

The Royal Society

Subject

Pharmacology (medical)

Reference16 articles.

1. Batchelor G. K. 1953

2. On the Theory of Plasma Waves

3. Theory of Plasma Oscillations. A. Origin of Medium-Like Behavior

4. Effects of Plasma Boundaries in Plasma Oscillations

5. Chapman S. & Cowling T. C. 1953 The mathematical theory of non-uniform gases. Cambridge University Press.

Cited by 122 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3