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Title: Spectroscopic determination of H, He, and H{sub 2} temperatures in a large-scale microwave plasma source

Abstract

Emission spectroscopy was used for the diagnostic of a large-scale, slot antenna excited microwave plasma source operating in pure hydrogen and in helium-hydrogen and argon-hydrogen mixtures at low pressures (p=0.3 mbar) and microwave power ranging from 600 to 900 W. No evidence was found for excessive broadening of the H{sub {alpha}} line under the present operating conditions, even though this line was found to be broader than the helium singlet line at 667.8 nm. The Doppler temperatures corresponding to this helium line (400-900 K) are close to the rotational temperatures (300-800 K) determined from the Q branch of the Fulcher-{alpha} band under the same conditions. The kinetic temperature of H atoms corresponding to the Doppler broadening of the H{sub {alpha}} line varies spatially between 3100 and 3400 K (95% He-5% H{sub 2}, p=0.3 mbar, and P=900 W) and between 3350 and 3900 K (95% Ar-5% H{sub 2}, p=0.3 mbar, and P=600 W) keeping constant the mixture composition, pressure, and microwave power. The rotational H{sub 2} temperature in argon-hydrogen mixtures varies from 330 to 400 K under the same conditions. Therefore, the results presented here indicate that the kinetic temperature of H atoms is higher than the background gas temperature.

Authors:
; ; ;  [1];  [2]
  1. Centro de Fisica dos Plasmas, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal)
  2. (Serbia)
Publication Date:
OSTI Identifier:
20982751
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2496368; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANTENNAS; ARGON; DOPPLER BROADENING; ELECTRON TEMPERATURE; EMISSION SPECTROSCOPY; HELIUM; HYDROGEN; ION TEMPERATURE; MICROWAVE RADIATION; MIXTURES; PLASMA; PLASMA DIAGNOSTICS

Citation Formats

Tatarova, E., Dias, F. M., Ferreira, C. M., Puac, N., and Institute of Physics, Pregrevica 118, 11080 Belgrade. Spectroscopic determination of H, He, and H{sub 2} temperatures in a large-scale microwave plasma source. United States: N. p., 2007. Web. doi:10.1063/1.2496368.
Tatarova, E., Dias, F. M., Ferreira, C. M., Puac, N., & Institute of Physics, Pregrevica 118, 11080 Belgrade. Spectroscopic determination of H, He, and H{sub 2} temperatures in a large-scale microwave plasma source. United States. doi:10.1063/1.2496368.
Tatarova, E., Dias, F. M., Ferreira, C. M., Puac, N., and Institute of Physics, Pregrevica 118, 11080 Belgrade. Thu . "Spectroscopic determination of H, He, and H{sub 2} temperatures in a large-scale microwave plasma source". United States. doi:10.1063/1.2496368.
@article{osti_20982751,
title = {Spectroscopic determination of H, He, and H{sub 2} temperatures in a large-scale microwave plasma source},
author = {Tatarova, E. and Dias, F. M. and Ferreira, C. M. and Puac, N. and Institute of Physics, Pregrevica 118, 11080 Belgrade},
abstractNote = {Emission spectroscopy was used for the diagnostic of a large-scale, slot antenna excited microwave plasma source operating in pure hydrogen and in helium-hydrogen and argon-hydrogen mixtures at low pressures (p=0.3 mbar) and microwave power ranging from 600 to 900 W. No evidence was found for excessive broadening of the H{sub {alpha}} line under the present operating conditions, even though this line was found to be broader than the helium singlet line at 667.8 nm. The Doppler temperatures corresponding to this helium line (400-900 K) are close to the rotational temperatures (300-800 K) determined from the Q branch of the Fulcher-{alpha} band under the same conditions. The kinetic temperature of H atoms corresponding to the Doppler broadening of the H{sub {alpha}} line varies spatially between 3100 and 3400 K (95% He-5% H{sub 2}, p=0.3 mbar, and P=900 W) and between 3350 and 3900 K (95% Ar-5% H{sub 2}, p=0.3 mbar, and P=600 W) keeping constant the mixture composition, pressure, and microwave power. The rotational H{sub 2} temperature in argon-hydrogen mixtures varies from 330 to 400 K under the same conditions. Therefore, the results presented here indicate that the kinetic temperature of H atoms is higher than the background gas temperature.},
doi = {10.1063/1.2496368},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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