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Title: Steady-state isothermal bounded plasma with neutral dynamics

Abstract

The Tonks-Langmuir, Godyak, and Schottky steady-state isothermal models are extended when the dynamics of the neutral gas is taken into account. Exact analytic quadratures for the electron temperature, densities, and potential profiles are obtained for these three models within the plasma approximation. It is shown that, contrary to the uniform neutral pressure case, the particle and the power balance are both necessary to determine the electron temperature when neutral dynamics is included. When neutral dynamics is governed by collisions with ions, the neutral density that results from ionization is predicted to have a minimum at the center of the discharge, as indeed is observed in experiment. It is found that even a small amount of ionization can result in a rather strong neutral depletion. However, when the drag on neutrals due to collisions with ions is negligible, the predicted profile of the neutral density that results from intense ionization is reversed and exhibits an unexpected maximum at the center of the discharge.

Authors:
; ; ; ; ;  [1];  [2]
  1. Laboratoire de Physique et Technologie des Plasmas, Ecole Polytechnique, 91128 Palaiseau (France)
  2. (Israel)
Publication Date:
OSTI Identifier:
20960124
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 1; Other Information: DOI: 10.1063/1.2424558; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; APPROXIMATIONS; BOUNDARY LAYERS; CALCIUM NITRIDES; COLLISIONS; ELECTRON TEMPERATURE; ION TEMPERATURE; IONIZATION; IONS; PLASMA; PLASMA DENSITY; PLASMA PRESSURE; STEADY-STATE CONDITIONS

Citation Formats

Raimbault, J.-L., Liard, L., Rax, J.-M., Chabert, P., Fruchtman, A., Makrinich, G., and Sciences Department, Holon Institute of Technology, 52 Golomb Street, Holon 58102. Steady-state isothermal bounded plasma with neutral dynamics. United States: N. p., 2007. Web. doi:10.1063/1.2424558.
Raimbault, J.-L., Liard, L., Rax, J.-M., Chabert, P., Fruchtman, A., Makrinich, G., & Sciences Department, Holon Institute of Technology, 52 Golomb Street, Holon 58102. Steady-state isothermal bounded plasma with neutral dynamics. United States. doi:10.1063/1.2424558.
Raimbault, J.-L., Liard, L., Rax, J.-M., Chabert, P., Fruchtman, A., Makrinich, G., and Sciences Department, Holon Institute of Technology, 52 Golomb Street, Holon 58102. Mon . "Steady-state isothermal bounded plasma with neutral dynamics". United States. doi:10.1063/1.2424558.
@article{osti_20960124,
title = {Steady-state isothermal bounded plasma with neutral dynamics},
author = {Raimbault, J.-L. and Liard, L. and Rax, J.-M. and Chabert, P. and Fruchtman, A. and Makrinich, G. and Sciences Department, Holon Institute of Technology, 52 Golomb Street, Holon 58102},
abstractNote = {The Tonks-Langmuir, Godyak, and Schottky steady-state isothermal models are extended when the dynamics of the neutral gas is taken into account. Exact analytic quadratures for the electron temperature, densities, and potential profiles are obtained for these three models within the plasma approximation. It is shown that, contrary to the uniform neutral pressure case, the particle and the power balance are both necessary to determine the electron temperature when neutral dynamics is included. When neutral dynamics is governed by collisions with ions, the neutral density that results from ionization is predicted to have a minimum at the center of the discharge, as indeed is observed in experiment. It is found that even a small amount of ionization can result in a rather strong neutral depletion. However, when the drag on neutrals due to collisions with ions is negligible, the predicted profile of the neutral density that results from intense ionization is reversed and exhibits an unexpected maximum at the center of the discharge.},
doi = {10.1063/1.2424558},
journal = {Physics of Plasmas},
number = 1,
volume = 14,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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