Improving particle beam acceleration in plasmas

TL;DR

This paper explores how a perturbing invariant robust barrier can enhance particle acceleration in magnetized plasmas by modifying phase space dynamics and controlling chaos, thereby increasing achievable particle energies.

Contribution

It introduces a novel method of using a perturbing invariant robust barrier to enlarge the wave amplitude range for effective particle acceleration in plasmas.

Findings

The robust barrier enables effective acceleration for particles near rest energy at low wave amplitudes.

At higher wave amplitudes, the barrier controls chaos and restores acceleration.

Optimal barrier placement in phase space increases final particle energy.

Abstract

The dynamics of wave-particle interactions in magnetized plasmas restricts the wave amplitude to moderate values for particle beam acceleration from rest energy. We analyze how a perturbing invariant robust barrier modifies the phase space of the system and enlarges the wave amplitude interval for particle acceleration. For low values of the wave amplitude, the acceleration becomes effective for particles with initial energy close to the rest energy. For higher values of the wave amplitude, the robust barrier controls chaos in the system and restores the acceleration process. We also determine the best position for the perturbing barrier in phase space in order to increase the final energy of the particles.