Some Aspects of Electron Dynamics in Electron Cyclotron Resonance Ion Sources

TL;DR

This paper uses numerical simulations to analyze electron behavior in Electron Cyclotron Resonance Ion Sources, revealing how electron energies, confinement, and heating are affected by various operational parameters.

Contribution

It introduces a combined Particle-In-Cell and ion dynamics simulation approach to study electron behavior in ECR ion sources, highlighting the effects of microwave fields and gas flow.

Findings

Mean electron energy around 70 keV

Electron lifetime governed by low-energy electron losses

Electron heating rate influences confinement and losses

Abstract

Electron dynamics in Electron Cyclotron Resonance Ion Source is numerically simulated by using Particle-In-Cell code combined with simulations of the ion dynamics. Mean electron energies are found to be around 70 keV close to values that are derived from spectra of X-ray emission out of the source. Electron life time is defined by losses of low-energy electrons created in ionizing collisions; the losses are regulated by electron heating rate, which depends on magnitude of the microwave electric field. Changes in ion confinement with variations in the microwave electric field and gas flow are simulated. Influence of electron dynamics on the afterglow and two-frequency heating effects is discussed.