Diffusion regime of electron-electron collisions in weakly ionized plasmas

TL;DR

This paper investigates how electron-electron collision dynamics in weakly ionized plasmas differ from fully ionized ones, emphasizing the role of electron diffusion due to frequent neutral scattering in thermalization processes.

Contribution

It provides a new analysis of electron thermalization in weakly ionized plasmas, including a rigorous derivation of the kinetic equation using the Bogolyubov method.

Findings

Diffusion significantly affects electron-electron collision rates.

Estimated characteristic time for electron thermalization in weakly ionized plasma.

Derived kinetic equation for electrons using advanced theoretical methods.

Abstract

We consider weakly ionized plasma where frequent elastic scattering of electrons on neutrals change the individual acts and the rate of electron-electron collisions significantly. In this case, the kinetics of electron thermalization is very different from that in fully ionized plasma. The colliding electrons diffuse because of fast scattering on neutrals. We demonstrate how a proper account of this diffusion enables one to estimate the characteristic time of electron thermalization. We also present a rigorous derivation of the kinetic equation for electrons by using Bogolyubov method based on Liouville equations for multi-particle distribution functions.