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How electron two-stream instability drives cyclic Langmuir collapse and continuous coherent emission.

ABSTRACT: Continuous plasma coherent emission is maintained by repetitive Langmuir collapse driven by the nonlinear evolution of a strong electron two-stream instability. The Langmuir waves are modulated by solitary waves in the linear stage and electrostatic whistler waves in the nonlinear stage. Modulational instability leads to Langmuir collapse and electron heating that fills in cavitons. The high pressure is released via excitation of a short-wavelength ion acoustic mode that is damped by electrons and reexcites small-scale Langmuir waves; this process closes a feedback loop that maintains the continuous coherent emission.

SUBMITTER: Che H

PROVIDER: S-EPMC5321042 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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How electron two-stream instability drives cyclic Langmuir collapse and continuous coherent emission.

Che Haihong H Goldstein Melvyn L ML Diamond Patrick H PH Sagdeev Roald Z RZ

Proceedings of the National Academy of Sciences of the United States of America 20170130 7

Continuous plasma coherent emission is maintained by repetitive Langmuir collapse driven by the nonlinear evolution of a strong electron two-stream instability. The Langmuir waves are modulated by solitary waves in the linear stage and electrostatic whistler waves in the nonlinear stage. Modulational instability leads to Langmuir collapse and electron heating that fills in cavitons. The high pressure is released via excitation of a short-wavelength ion acoustic mode that is damped by electrons a ...[more]

PMID: 28137887

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