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arXiv · 2512.07895

Ion-acoustic shock and solitary waves in magnetized plasma with Cairns-Gurevich distribution electrons

Rui Huo·Jiulin Du
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Abstract

The propagation properties of ion-acoustic solitary and shock waves in the magnetized viscous plasma with nonthermal trapped electrons are investigated. The Cairns-Gurevich distribution as the electron distribution is considered to describe the plasma nonthermality and particle trapping. By adopting the reductive perturbation technique, we derived the nonlinear Schamel-Korteweg-de Vries-Burgers (SKdVB) equation, and then obtained the ion-acoustic shock and solitary wave solutions of the SKdVB equation for different limiting cases. It is found that the impact of nonthermal parameter {\alpha}, external magnetic field {\Omega}, obliqueness lz, wave speed U0, and the ion kinematic viscosity {\eta}0 can significantly change the characteristics of the shock and solitary waves. These results may be useful for better understanding the propagation of nonlinear structures in space (i.e. Earth's magnetosphere and ionosphere, auroral regions) and laboratory plasma with nonthermal trapped electrons.

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Rui Huo, Jiulin Du. 2025-12-04. Ion-acoustic shock and solitary waves in magnetized plasma with Cairns-Gurevich distribution electrons. https://arxiv.org/abs/2512.07895

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