Accession Number : AD0263449

Title :   TRANSVERSE DIFFUSION IN A QUASI-STATIC POSITIVE COLUMN

Corporate Author : BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH

Personal Author(s) : JOHNSON,ROY R. ; JERDE,DAVID A.

Report Date : SEP 1961

Pagination or Media Count : 1

Abstract : The transverse diffusion of a diverging positive column in a slowly varying magnetic field is measured experimentally, and compared with the corresponding steady-state theory. The theory is developed from the macroscopic equations for momentum and particle conservation, taking into account only charged particle-neutral atom collisions. Reasonable agreement is found between theory and experiment for discharge currents in Helium of the order of 50 - 500 ma, pressures of 0.6 to 1.0 mm Hg, and peak magnetic fields of up to 15 kilogauss. Rise times of the magnetic field are between 1 and 8 kilogauss/m sec. Unstable behavior of the current is observed only after the peak magnetic field is reached, even though the peak values are greater than the critical values observed by Lehnert (Phys. of fluids 3:600, 1960) and Allen et al (Phys. Rev. Hr. 5:409, 1960) for the onset of enhanced diffusion. (Author)

Descriptors :   *DIFFUSION, *MAGNETIC FIELDS, *PARTICLES, DISCHARGE TUBES, ELECTRIC DISCHARGES, HELIUM, INTEGRAL EQUATIONS, KINETIC THEORY, MATHEMATICAL ANALYSIS, PLASMAS(PHYSICS)

Distribution Statement : APPROVED FOR PUBLIC RELEASE