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

Abstract

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
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 22; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X
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

Citation Formats

Campanell, M. D., E-mail: michaelcampanell@gmail.com. Entire plasmas can be restructured when electrons are emitted from the boundaries. United States: N. p., 2015. Web. doi:10.1063/1.4918339.
Campanell, M. D., E-mail: michaelcampanell@gmail.com. Entire plasmas can be restructured when electrons are emitted from the boundaries. United States. https://doi.org/10.1063/1.4918339
Campanell, M. D., E-mail: michaelcampanell@gmail.com. 2015. "Entire plasmas can be restructured when electrons are emitted from the boundaries". United States. https://doi.org/10.1063/1.4918339.
@article{osti_22408282,
title = {Entire plasmas can be restructured when electrons are emitted from the boundaries},
author = {Campanell, M. D., E-mail: michaelcampanell@gmail.com},
abstractNote = {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.},
doi = {10.1063/1.4918339},
url = {https://www.osti.gov/biblio/22408282}, journal = {Physics of Plasmas},
issn = {1070-664X},
number = 4,
volume = 22,
place = {United States},
year = {Wed Apr 15 00:00:00 EDT 2015},
month = {Wed Apr 15 00:00:00 EDT 2015}
}

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Works referencing / citing this record:

Are two plasma equilibrium states possible when the emission coefficient exceeds unity?
journal, May 2017


Kinetic modeling of the electronic response of a dielectric plasma-facing solid
journal, July 2017


Sheath structure in plasma with two species of positive ions and secondary electrons
journal, February 2016


Strongly Emitting Surfaces Unable to Float below Plasma Potential
journal, February 2016