Influence of kinetic effects on the spectrum of a parallel electrode probe

TL;DR

This paper derives an explicit response function for kinetic Active Plasma Resonance Spectroscopy in simple geometries, revealing that kinetic effects cause increased damping in the plasma resonance spectra.

Contribution

It provides a new analytical response function for kinetic APRS models using a matrix representation, highlighting the impact of kinetic effects on damping.

Findings

Kinetic effects lead to stronger damping in plasma resonance spectra.

Explicit response function derived for simple geometries.

Method enables computation of approximate spectra considering kinetic effects.

Abstract

Active Plasma Resonance Spectroscopy (APRS) denotes a class of diagnostic techniques which utilize the natural ability of plasmas to resonate on or near the electron plasma frequency. One particular class of APRS can be described in an abstract notation based on functional analytic methods in electrostatic approximation. These methods allow for a general solution of the kinetic model in arbitrary geometry. This solution is given as the response function of the probe-plasma system and is defined by the resolvent of an appropriate dynamical operator. The general response predicts an additional damping due to kinetic effects. This manuscript provides the derivation of an explicit response function of the kinetic APRS model in a simple geometry. Therefore, the resolvent is determined by its matrix representation based on an expansion in orthogonal basis functions. This allows to compute an approximated response function. The resulting spectra show clearly a stronger damping due to kinetic effects.