Non-planar electron-acoustic waves with hybrid Cairns–Tsallis distribution

Abstract

Non-planar electron-acoustic waves having Cairns–Tsallis distributed hot electrons are investigated under multiple temperature electrons model in unmagnetised plasma. In this model, Korteweg–de Vries (KdV) equation is obtained in the cylindrical / spherical coordinates. On the basis of the solutions of KdV equation, variation of solitary wave features (amplitude, velocity and width) with different plasma parameters are analysed. Dispersion and nonlinear coefficients obtained depend on the particle density $\alpha$, non-extensive parameter q, electron temperature ratio $\theta$ and non-thermal parameter $\gamma$. Combined effect of all these plasma parameters significantly changes the properties of the solitary waves in non-planar geometry. It is observed that increasing the number of non-thermal electrons in the medium increases the amplitude, velocity as well as width of the non-planar waves whereas with the increase in temperature, the velocity of waves decreases and this impact is dominant in spherical waves. This two-parameter $(\gamma , q)$ distribution model (C–T) is applicable to a wide range of observed plasmas, i.e. auroral region and magnetosphere of the Earth.