On the breaking of a plasma wave in a thermal plasma: I. The structure of the density singularity

TL;DR

This paper investigates the structure of density singularities in relativistic plasma waves near wavebreaking, using a waterbag electron distribution, and compares thermal and cold plasma electric field limits through theory and simulations.

Contribution

It introduces a simple waterbag model to analyze the density singularity structure in thermal plasma waves near wavebreaking, providing theoretical and simulation-based insights.

Findings

Electron density forms a 'peakon' structure at wavebreaking

Maximum electric field in thermal plasma exceeds cold plasma limit

Simulation results agree with theoretical predictions

Abstract

The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wavebreaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical "peakon" form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions.