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Title: Space charge neutralization in inertial electrostatic confinement plasmas

Abstract

A major issue for electron injected inertial electrostatic confinement (IEC) devices is space charge neutralization. A new formalism is developed that will allow this neutralization to occur for both oscillating and steady-state IEC plasmas. Results indicate that there are limits on the amount of compression that can be achieved by oscillating plasmas while simultaneously maintaining space charge neutralization and parabolic background potential. For steady-state plasmas, there are no such limits and space charge neutralization can be achieved even when the plasma becomes quasineutral.

Authors:
; ; ; ;  [1]
  1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
20974937
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 4; Other Information: DOI: 10.1063/1.2711173; (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; COMPRESSION; ELECTRONS; EQUIPMENT; INERTIAL CONFINEMENT; PLASMA; PLASMA WAVES; POTENTIALS; SPACE CHARGE; STEADY-STATE CONDITIONS

Citation Formats

Evstatiev, E. G., Nebel, R. A., Chacon, L., Park, J., and Lapenta, G.. Space charge neutralization in inertial electrostatic confinement plasmas. United States: N. p., 2007. Web. doi:10.1063/1.2711173.
Evstatiev, E. G., Nebel, R. A., Chacon, L., Park, J., & Lapenta, G.. Space charge neutralization in inertial electrostatic confinement plasmas. United States. doi:10.1063/1.2711173.
Evstatiev, E. G., Nebel, R. A., Chacon, L., Park, J., and Lapenta, G.. Sun . "Space charge neutralization in inertial electrostatic confinement plasmas". United States. doi:10.1063/1.2711173.
@article{osti_20974937,
title = {Space charge neutralization in inertial electrostatic confinement plasmas},
author = {Evstatiev, E. G. and Nebel, R. A. and Chacon, L. and Park, J. and Lapenta, G.},
abstractNote = {A major issue for electron injected inertial electrostatic confinement (IEC) devices is space charge neutralization. A new formalism is developed that will allow this neutralization to occur for both oscillating and steady-state IEC plasmas. Results indicate that there are limits on the amount of compression that can be achieved by oscillating plasmas while simultaneously maintaining space charge neutralization and parabolic background potential. For steady-state plasmas, there are no such limits and space charge neutralization can be achieved even when the plasma becomes quasineutral.},
doi = {10.1063/1.2711173},
journal = {Physics of Plasmas},
number = 4,
volume = 14,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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  • A numerical study is reported on the equilibrium properties of a surface-emitted or edge-confined non-drifting plasma. A self-consistent finite-differences evaluation of the electrostatic potential is carried out for a non-neutral plasma that follows a Boltzmann density distribution. The non-neutral plasma generates an electrostatic potential that has an extremum at the geometric center. Poisson's equation is solved for different ratios of the non-neutral plasma size to the edge Debye length. The profiles of the electrostatic potential and the plasma density are presented for different values of that ratio. A second plasma species is then introduced for two-plasma-species confinement studies, with onemore » species confined by the space charge of the other, while each species follows a Boltzmann density distribution. An equilibrium in which a neutral region forms is found. An equilibrium is also found in which the two species have equal temperatures and charge states.« less