Related Experiment Video
Updated: Dec 29, 2025

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry
Published on: August 1, 2017
Study of gasdynamic electron cyclotron resonance plasma vacuum ultraviolet emission to optimize negative hydrogen ion
R L Lapin1, V A Skalyga1, I Izotov1
1Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod, Russia.
Abstract:
Negative hydrogen ion sources are used as injectors into accelerators and drive the neutral beam heating in ITER. Certain processes in low-temperature hydrogen plasmas are accompanied by the emission of vacuum ultraviolet (VUV) emission. Studying the VUV radiation, therefore, provides volumetric rates of plasma-chemical processes and plasma parameters. In the past, we have used gasdynamic ECR discharge for volumetric negative ion production and investigated the dependencies between the extracted H- current density and various ion source parameters. It was shown that it is possible to reach up to 80 mA/cm2 of negative ion current density with a two electrode extraction. We report experimental studies on negative hydrogen ion production in a high-density gasdynamic ECR discharge plasma consisting of two simple mirror traps together with the results of VUV emission measurements. The VUV-power was measured in three ranges-Lyα, Lyman band, and molecular continuum-varying the source control parameters near their optima for H- production. It was shown that the molecular continuum emission VUV power is the highest in the first chamber while Lyα emission prevails in the second one. Modifications for the experimental scheme for further optimization of negative hydrogen ion production are suggested.
Related Concept Videos
Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
Atomic Emission Spectroscopy: Lab
Atomic Emission Spectroscopy: Overview
Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview

