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arXiv · 1609.02280

Harmonics Effect on Ion-Bulk Waves in CH Plasmas

Q. S. Feng·C. Y. Zheng·Z. J. Liu·L. H. Cao·C. Z. Xiao·Q. Wang·X. T. He
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Abstract

The harmonics effect on ion-bulk (IBk) waves has been researched by Vlasov simulation. The condition of excitation of a large-amplitude IBk waves is given to explain the phenomenon of strong short-wavelength electrostatic activity in solar wind. When $k$ is much lower than $k_{lor}/2$ ($k_{lor}$ is the wave number at loss-of-resonance point), the IBk waves will not be excited to a large amplitude, because a large part of energy will be spread to harmonics. The nature of nonlinear IBk waves in the condition of $k<k_{lor}/2$ is undamped Bernstein-Greene-Kruskal-like waves with harmonics superposition. Only when the wave number $k$ of IBk waves satisfies $k_{lor}/2\lesssim k\leq k_{lor}$, can a large-amplitude and mono-frequency IBk wave be excited. These results give a guidance for a novel scattering mechanism related to IBk waves in the field of laser plasma interaction.

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Q. S. Feng, C. Y. Zheng, Z. J. Liu, L. H. Cao, C. Z. Xiao, Q. Wang, X. T. He. 2016-09-08. Harmonics Effect on Ion-Bulk Waves in CH Plasmas. https://doi.org/10.1088/1361-6587/aa73a2

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