Floating sheath potentials in non-Maxwellian plasmas

Journal Article · Fri Feb 01 04:00:00 EST 1985 · IEEE Trans. Plasma Sci.; (United States)

DOI:https://doi.org/10.1109/TPS.1985.4316351· OSTI ID:5366108

Kushner, M J

The floating sheath potential in a plasma having a Maxwellian electron distribution function is e/PHI/ /sub s/ = kT /sub e/ In (a/b)/2 where T /sub e/ is the electron temperature, a is the ratio of electron temperature to ion temperature, and b is the ratio of electron mass to ion mass. This expression is derived by equating the flux of electrons and ions to a surface in the plasma. Only electrons initially having an energy greater than -e/PHI/ /sub s/ flow to the surface. these electrons are in the tail of the distribution, a region that differs significantly from a Maxwellian in many plasmas. An analysis is performed where the sheath potential is solved for using a two-temperature model for the electron distribution function. The two-temperature model accurately describes the distortion from a Maxwellian in the tail of the distribution function. The magnitude of the sheath potential calculated with the two-temperature distribution is significantly smaller than that obtained using a Maxwellian distribution, a result of the reduction in the relative abundance of energetic electrons in the tail of the distribution.

• Research Organization: Mathematical Sciences Northwest, Inc., (Spectra Technology, Inc.), Bellevue, WA 98004
• OSTI ID: 5366108
• Journal Information: IEEE Trans. Plasma Sci.; (United States), Journal Name: IEEE Trans. Plasma Sci.; (United States) Vol. PS-13:1; ISSN ITPSB
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
DISTRIBUTION
ELECTRIC POTENTIAL
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
INSTABILITY
ION TEMPERATURE
LEPTONS
PLASMA
PLASMA DENSITY
PLASMA INSTABILITY
PLASMA SHEATH