Multi-fluid approach to high-frequency waves in plasmas. III. Nonlinear regime and plasma heating

TL;DR

This paper explores the nonlinear behavior of high-frequency waves in partially ionized plasmas, revealing how collisional interactions lead to wave dissipation and plasma heating, with implications for solar prominence conditions.

Contribution

It extends multi-fluid plasma modeling to the nonlinear regime, analyzing how ion-neutral collisions influence wave evolution and heating in partially ionized plasmas.

Findings

Collisional friction dissipates wave energy as heat.

Nonlinear effects are more significant in standing waves.

Plasma temperature increases due to frictional heating.

Abstract

The multi-fluid modelling of high-frequency waves in partially ionized plasmas has shown that the behavior of magnetohydrodynamics waves in the linear regime is heavily influenced by the collisional interaction between the different species that form the plasma. Here, we go beyond linear theory and study large-amplitude waves in partially ionized plasmas using a nonlinear multi-fluid code. It is known that in fully ionized plasmas, nonlinear Alfv\'en waves generate density and pressure perturbations. Those nonlinear effects are more pronounced for standing oscillations than for propagating waves. By means of numerical simulations and analytical approximations, we examine how the collisional interaction between ions and neutrals affects the nonlinear evolution. The friction due to collisions dissipates a fraction of the wave energy, which is transformed into heat and consequently rises the temperature of the plasma. As an application, we investigate frictional heating in a plasma with physical conditions akin to those in a solar quiescent prominence.