Spherical probe in a flowing plasma

Abstract
Ion flow is important in many laboratory discharges, vacuum switches, gas-filled valves, thyratrons and space satellites. A model is presented for subsonic ion flow past a negative spherical probe immersed in a collisionless ionization-free plasma; a stagnation point develops downstream. Although the floating potential given by previous analyses (which all assume spherical symmetry) is substantially correct, there is some dependence on the ion flow velocity (a few % at M=0.5). Thus the change in floating potential can be used to measure ion flow. In general, only slight modification needs to be made to low pressure probe theories in order to include flow effects.

This publication has 17 references indexed in Scilit: