Ultrafast Electron Holes in Plasma Phase Space Dynamics

TL;DR

This paper introduces a new recursive distribution function for electron holes in plasma, presents nonlinear kinetic simulation results at high velocities, and analyzes their stability and collision behavior.

Contribution

A novel recursive distribution function for electron holes is proposed, extending previous models and enabling detailed kinetic simulation analysis.

Findings

Electron holes can propagate at velocities twice the electron thermal speed.

The stability of electron holes is confirmed through long-term simulation.

Electron holes exhibit characteristic behaviors during mutual collisions.

Abstract

Electron holes (EH) are localized modes in plasma kinetic theory which appear as vortices in phase space. Earlier research on EH is based on the Schamel distribution function (df). A novel distribution function is proposed here, generalizing the original Schamel df in a recursive manner. Nonlinear solutions obtained by kinetic simulations are presented, with velocities twice the electron thermal speed. Using 1D-1V kinetic simulations, their propagation characteristics are traced and their stability is established by studying their long-time evolution and their behavior through mutual collisions.