Effects of dispersive wave modes on charged particles transport

TL;DR

This paper investigates how dispersive wave modes influence charged particle transport, especially electrons, in space plasmas by using particle-in-cell simulations to analyze wave-particle interactions in the kinetic regime.

Contribution

It introduces a detailed analysis of dispersive wave effects on electron transport using PIC simulations, extending understanding beyond traditional non-dispersive models.

Findings

Dispersive waves significantly affect electron scattering in the kinetic regime.

The kinetic regime alters the resonance conditions for wave-particle interactions.

Simulation results highlight the importance of dispersive effects in space plasma transport.

Abstract

The transport of charged particles in the heliosphere and the interstellar medium is governed by the interaction of particles and magnetic irregularities. For the transport of protons a rather simple model using a linear Alfv\'en wave spectrum which follows the Kolmogorov distribution usually yields good results. Even magnetostatic spectra may be used. For the case of electron transport, particles will resonate with the high-k end of the spectrum. Here the magnetic fluctuations do not follow the linear dispersion relation, but the kinetic regime kicks in. We will discuss the interaction of fluctuations of dispersive waves in the kinetic regime using a particle-in-cell code. Especially the scattering of particles following the idea of Lange et al. (2013) and its application to PiC codes will be discussed. The effect of the dispersive regime on the electron transport will be discussed in detail.