Ion response in a weakly ionized plasma with ion flow

TL;DR

This paper extends classical Landau analysis to study ion response in weakly ionized plasmas with ion flow, incorporating ion-neutral collisions and electric fields, and shows how to determine ion wave frequencies from susceptibility expressions.

Contribution

It introduces a method to derive complex ion wave frequencies in ionized plasmas with flow and collisions using known susceptibility formulas.

Findings

Complex ion wave frequencies can be obtained from existing susceptibility expressions.

Ion response analysis includes ion-neutral collisions and electric field effects.

The approach simplifies the calculation of ion wave characteristics in plasma physics.

Abstract

We study the ion response to an initial perturbation in a weakly ionized plasma with ion flow driven by a dc electric field. The analysis is made by extending the classical Landau work [J. Phys. (USSR) 10, 25 (1946)] to the ion kinetic equation including ion-neutral collisions and a dc electric field. We show, in particular, that the complex frequencies of ion waves can be directly found from a known expression for the ion susceptibility [Phys. Rev. E 71, 016405 (2005); Phys. Rep. 27, 997 (2001)]; this is not obvious from its original derivation, because it only aims to describe the ion response for real frequencies.