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Title: Space charge modes in the magnetized discharge with dust

Abstract

The structure of a discharge across a magnetic field in a dusty plasma is analysed. The dust macroparticles are negatively charged, but are unmagnetized because of their high mass. The electrons are highly magnetized, and the ions have intermediate magnetization. This results in different transport rates of the different species across the magnetic field. Depending on the size of the magnetic field, and the relative charge on the different species, the dust grains can be the dominant current carrier. The space charge near the electrodes will then be determined by the relative mobility of the different species. The discharge can operate in one of two modes, a positive space charge (PSC) mode, characterized by a strong cathode fall, and a negative space charge (NSC) mode, characterized by a broad anode fall. Features unique to the dust particles can play a role in the structure of the discharge, such as the variable equilibrium charge on the grains, dependent on the local potential. A fluid model of the different species is used to calculate the structure of the resulting discharge.

Authors:
;  [1]
  1. School of Physics, University of Sydney, N.S.W. 2006 (Australia)
Publication Date:
OSTI Identifier:
20726841
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 799; Journal Issue: 1; Conference: 4. international conference on the physics of dusty plasmas, Orleans (France), 13-17 Jun 2005; Other Information: DOI: 10.1063/1.2134690; (c) 2005 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; ANODES; CATHODES; DUSTS; ELECTRIC CURRENTS; ELECTRONS; EQUILIBRIUM; FLUIDS; IONS; MAGNETIC FIELDS; MAGNETIZATION; MOBILITY; PARTICLES; PLASMA; POTENTIALS; SPACE CHARGE

Citation Formats

Cramer, N.F., and Vladimirov, S.V. Space charge modes in the magnetized discharge with dust. United States: N. p., 2005. Web. doi:10.1063/1.2134690.
Cramer, N.F., & Vladimirov, S.V. Space charge modes in the magnetized discharge with dust. United States. doi:10.1063/1.2134690.
Cramer, N.F., and Vladimirov, S.V. Mon . "Space charge modes in the magnetized discharge with dust". United States. doi:10.1063/1.2134690.
@article{osti_20726841,
title = {Space charge modes in the magnetized discharge with dust},
author = {Cramer, N.F. and Vladimirov, S.V.},
abstractNote = {The structure of a discharge across a magnetic field in a dusty plasma is analysed. The dust macroparticles are negatively charged, but are unmagnetized because of their high mass. The electrons are highly magnetized, and the ions have intermediate magnetization. This results in different transport rates of the different species across the magnetic field. Depending on the size of the magnetic field, and the relative charge on the different species, the dust grains can be the dominant current carrier. The space charge near the electrodes will then be determined by the relative mobility of the different species. The discharge can operate in one of two modes, a positive space charge (PSC) mode, characterized by a strong cathode fall, and a negative space charge (NSC) mode, characterized by a broad anode fall. Features unique to the dust particles can play a role in the structure of the discharge, such as the variable equilibrium charge on the grains, dependent on the local potential. A fluid model of the different species is used to calculate the structure of the resulting discharge.},
doi = {10.1063/1.2134690},
journal = {AIP Conference Proceedings},
number = 1,
volume = 799,
place = {United States},
year = {Mon Oct 31 00:00:00 EST 2005},
month = {Mon Oct 31 00:00:00 EST 2005}
}
  • Dust acoustic solitary waves in a magnetized dusty plasma are studied taking into account the effect of dust size and dust charge variations. Using the analytical and numerical results the influence of different plasma parameters on dust acoustic solitary waves are examined. It is observed that the dust size distribution and dust charge variation has significant contribution on the characteristics of dust acoustic solitary waves.
  • Dust acoustic solitary waves in a magnetized dusty plasma are studied taking into account the effect of dust size and dust charge variations. Using the analytical and numerical results the influence of different plasma parameters on dust acoustic solitary waves are examined. It is observed that the dust size distribution and dust charge variation have significant contributions on the characteristics of dust acoustic solitary waves.
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