Theory of a cylindrical probe in a collisionless magnetoplasma

Journal Article · Wed Dec 01 04:00:00 EST 1976 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.861425· OSTI ID:7337697

Laframboise, J G; Rubinstein, J

A theory is presented for a cylindrical electrostatic probe in a collisionless plasma, when the probe axis is inclined at an angle theta to a uniform magnetic field. The theory is applicable to electron collection, and under more restrictive conditions, to ion collection. For a probe at space potential, the theory is exact in the limit when probe radius r/sub p/very-much-less-than Debye length lambda/sub D/. At attracting probe potentials, the theory yields an upper bound and an adiabatic limit for current collection. At repelling probe potentials, it provides a lower bound. The theory is valid if r/sub p//lambda/sub D/ and r/sub p//a-bar, where a-bar is the mean gyroradius, are not simultaneously large enough to produce extrema in the probe sheath potential. The numerical current calculations are based on the approximation that particle orbits are helices near the probe, together with the use of kinetic theory to relate velocity distributions near the probe to those far from it. Probe characteristics are presented for theta from 0degree to 90degree, and for r/sub p//a-bar from 0.1 to infinity. For theta=0degree, the end-effect current is calculated separately. (AIP)

• Research Organization: Centre de Recherches en Physique de L'Environnement, 45 Orleans-La Source, France
• OSTI ID: 7337697
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 19:12; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
BOUNDARY CONDITIONS
COLLISIONLESS PLASMA
CURRENTS
ELECTRIC CURRENTS
ELECTROSTATIC PROBES
MAGNETIC FIELDS
PLASMA
PLASMA DIAGNOSTICS
PROBES
VELOCITY