Observation of plasma production in a multipole device

Abstract

Plasma production is observed in a simple discharge model of one filament cathode and a multipole magnet anode with variable electrode separation. Two-dimensional velocity distribution functions of electrons and ions and two-dimensional spatial profiles of the potential and electron density are measured with a directional energy analyzer, an emissive probe, and a Langmuir probe. The electrode distance is found to affect the plasma production for isotropic velocity distribution, quiescent plasma, and homogeneous spatial distributions of the potential and electron density. The results may help to explain the fundamental plasma physics of a multipole double plasma machine.