Electron Self-injection in Multidimensional Relativistic Plasma Wakefields

TL;DR

This paper develops an analytical model for electron self-injection in multidimensional plasma wakefields, explaining trapping conditions and cross sections, validated by 3D PIC simulations, relevant for high-energy electron acceleration.

Contribution

It introduces a new analytical model for electron trapping in multidimensional plasma wakefields, applicable to bubble and blowout regimes, with validation against simulations.

Findings

Model accurately predicts trapping conditions and cross sections.

Results agree well with 3D PIC simulation data.

Provides insights into electron acceleration mechanisms.

Abstract

We present an analytical model for electron self-injection in nonlinear, multidimensional plasma wave excited by short laser pulse in the bubble regime or by short electron beam in the blowout regime. In this regimes, which are typical for electron acceleration in the last experiments, the laser radiation pressure or the electron beam charge pushes out background plasma electrons forming a plasma cavity - bubble - with a huge ion charge. The plasma electrons can be trapped in the bubble and accelerated by the plasma wakefields up to very high energies. The model predicts the condition for electron trapping and the trapping cross section in terms of the bubble radius and the bubble velocity. The obtained results are in a good agreement with results of 3D PIC simulations.