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arXiv · 2507.20626

Characterizing ion-acoustic shock wave collisions in Martian multicomponent plasma environments

Jayshree Mondal·Prasanta Chatterjee·Laxmikanta Mandi·Biswajit Sahu
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Abstract

We present theoretical investigation of colliding ion-acoustic (IA) shock waves in Martian multicomponent plasmas consisting of hydrogen ($H^+$), oxygen ($O^+$) and oxygen molecule ($O_2^+$) ions, including background superthermal electrons (modeled by a $\kappa$-(kappa) distribution function). A set of Burgers' equations is obtained by adopting a modified Poincar\'e-Lighthill-Kuo (PLK) perturbation method to describe the head-on-collision dynamics of dissipative nonlinear IA wave structures. We have estimated the spatio-temporal scales using parameters typically observed in the Martian atmosphere by the MAVEN spacecraft, for which shock waves are theoretically expected to undergo mutual collisions in the multicomponent plasma. The effects of head-on collisions on the electrostatic potential profiles arising from one-fold and two-fold IA shock interactions are explored. Our numerical analysis reveals that the collision leads to a noticeable broadening of the shock structures with the enhancement of kinematic viscosity.

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Jayshree Mondal, Prasanta Chatterjee, Laxmikanta Mandi, Biswajit Sahu. 2025-07-28. Characterizing ion-acoustic shock wave collisions in Martian multicomponent plasma environments. https://arxiv.org/abs/2507.20626

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