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Nontrapping arrest of Langmuir wave damping near the threshold amplitude

A. V. Ivanov·Iver H. Cairns
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Abstract

Evolution of a Langmuir wave is studied numerically for finite amplitudes slightly above the threshold which separates damping from nondamping cases. Arrest of linear damping is found to be a second-order effect due to ballistic evolution of perturbations, resonant power transfer between field and particles, and organization of phase space into a positive slope for the average distribution function $f_{av}$ around the resonant wave phase speed $v_ϕ$. Near the threshold trapping in the wave potential does not arrest damping or saturate the subsequent growth phase.

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A. V. Ivanov, Iver H. Cairns. 2006-04-26. Nontrapping arrest of Langmuir wave damping near the threshold amplitude. https://doi.org/10.1103/physrevlett.96.175001

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