skip to main content

SciTech ConnectSciTech Connect

Title: Spectral diagnostics based on Doppler-broadened H{sub α} line shape in a single element of a matrix source

The study is on optical emission spectroscopy diagnostics of a single element of a matrix source of negative hydrogen ions. The method developed for description of the hydrogen atoms behaviour is based on analysis of the Balmer H{sub α} line profile, and it can be readily applied to various low pressure hydrogen discharges. The present observations reveal the existence of thermal as well as of non-thermal fast hydrogen atoms in the discharge. For processing of the experimental data a line shape model, which accounts for details of the plasma kinetics and the fine structure of the Balmer lines is developed. The fit of this model to the recorded at different experimental conditions line shapes results in the temperature of the thermal atoms, the mean energy of the fast atoms, the ratio between the densities of these two group of atoms and the relative populations of the fine structure components of the n = 3 hydrogen state. The present study indicates that the reactions leading to production of fast atoms and the process of energy exchange between thermal and fast atoms may be important for the correct modeling of the plasma kinetics.
Authors:
;  [1]
  1. Faculty of Physics, Sofia University, 5, J. Bourchier, BG-1164 Sofia (Bulgaria)
Publication Date:
OSTI Identifier:
22391434
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1655; Journal Issue: 1; Conference: NIBS 2014: 4. International Symposium on Negative Ions, Beams and Sources, Garching (Germany), 6-10 Oct 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; BALMER LINES; COMPUTERIZED SIMULATION; ELECTRIC DISCHARGES; EMISSION SPECTROSCOPY; ENERGY TRANSFER; FINE STRUCTURE; HYDROGEN; HYDROGEN IONS 1 MINUS; MATRICES; PLASMA