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arXiv · 1904.02185

Dust-acoustic envelope solitons in super-thermal plasmas

A. A. Noman·N. A. Chowdhury·A. Mannan·A. A. Mamun
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Abstract

The modulational instability (MI) of the dust-acoustic waves (DAWs) in an electron-positron-ion-dust plasma (containing super-thermal electrons, positrons and ions along with negatively charged adiabatic dust grains) is investigated by the analysis of the nonlinear Schrödinger equation (NLSE). To derive the NLSE, the reductive perturbation method has been employed. Two different parametric regions for stable and unstable DAWs are observed. The presence of super-thermal electrons, positrons and ions significantly modifies both the stable and unstable regions. The critical wave number $k_c$ (at which modulational instability sets in) depends on the super-thermal electron, positron, and ion, and adiabatic dust concentrations.

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A. A. Noman, N. A. Chowdhury, A. Mannan, A. A. Mamun. 2019-04-03. Dust-acoustic envelope solitons in super-thermal plasmas. https://doi.org/10.1002/ctpp.201900023

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