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Title: Entire plasmas can be restructured when electrons are emitted from the boundaries

It is well known that electron emission can restructure the thin sheaths at plasma-facing surfaces. But conventional models assume that the plasma's structure negligibly changes (the “presheath” is still thought to be governed by ion acceleration to the Bohm speed). Here, it is shown by theory and simulation that the presheath can take a fundamentally different structure where the emitted electrons entering the quasineutral region cause numerous changes. Gradients of total plasma density, ion and electron pressures, and electric potential throughout the “inverted” presheath can carry different magnitudes, and opposite signs, from Bohm presheaths.
Authors:
 [1]
  1. Lawrence Livermore National Laboratory, P.O. Box 808 (L-630), Livermore, California 94551 (United States)
Publication Date:
OSTI Identifier:
22408282
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; BOHM CRITERION; ELECTRIC POTENTIAL; ELECTRON EMISSION; FIRST WALL; IONS; PLASMA DENSITY; PLASMA SHEATH; SIMULATION