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Author Schmitz, H. ♦ Riemann, K. ♦ Daube, T.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword PLASMA PHYSICS AND FUSION ♦ PLASMA SHEATH ♦ TRANSPORT THEORY ♦ BOHM CRITERION ♦ BOUNDARY LAYERS ♦ COLLISIONAL PLASMA ♦ WALL EFFECTS ♦ SPACE CHARGE ♦ DEBYE LENGTH
Abstract In the limit of a small Debye length ({lambda}{sub D}{r_arrow}0) the plasma boundary layer in front of a negative absorbing wall is split up into a collision-free planar space charge sheath and a quasineutral presheath, where the ions are accelerated to fulfill the Bohm criterion. Apart from ion inertia, the mechanism of the presheath depends on an additional effect controlling the ion field acceleration. The present paper considers a stationary presheath dominated by the deflection of the ion orbits in a magnetic field parallel to the wall. The ion transport is provided by charge exchange collisions with cold neutrals. The potential profiles and ion distributions resulting from the self-consistent kinetic analysis are compared with expectations based on a previous hydrodynamic model. The transition from {open_quote}{open_quote}closed{close_quote}{close_quote} to {open_quote}{open_quote}open{close_quote}{close_quote} ion orbits results in typical deviations near the sheath edge. The kinetic Bohm criterion is found to be fulfilled marginally. {copyright} {ital 1996 American Institute of Physics.}
ISSN 1070664X
Educational Use Research
Learning Resource Type Article
Publisher Date 1996-07-01
Publisher Place United States
Journal Physics of Plasmas
Volume Number 3
Issue Number 7


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