Electronic temperatures, densities and plasma X-ray emission of a 14.5 GHz Electron-Cyclotron Resonance Ion Source

TL;DR

This study systematically analyzes Bremsstrahlung emission from a 14.5 GHz Electron-Cyclotron Resonance Ion Source, measuring plasma temperatures, densities, and X-ray emissions to enhance understanding of plasma behavior and ion charge states.

Contribution

It provides new measurements of plasma electronic temperature, density, and X-ray emission characteristics, demonstrating high-precision spectroscopy of highly charged ions.

Findings

Average plasma temperature of ~48 keV at >100W power

Charge state distributions of ion beams characterized

High-resolution X-ray spectra of highly charged argon ions obtained

Abstract

We have performed a systematic study of the Bremsstrahlung emission from the electrons in the plasma of a commercial 14.5 GHz Electron-Cyclotron Resonance Ion Source. The electronic spectral temperature and the product of ionic and electronic densities of the plasma are measured by analyzing the Bremsstrahlung spectra recorded for several rare gases (Ar, Kr, Xe) as a function of the injected power. Within our uncertainty, we find an average temperature of ? 48 keV above 100W, with a weak dependency on the injected power and gas composition. Charge state distributions of extracted ion beams have been determined as well, providing a way to disentangle the ionic density from the electronic density. Moreover X-ray emission from highly charged argon ions in the plasma has been observed with a high-resolution mosaic crystal spectrometer, demonstrating the feasibility for high-precision measurements of transition energies of highly charged ions, in particular of the magnetic dipole (M1) transition of He-like of argon ions.