Der Druckaufbau in einem stationären, magnetfeldstabilisierten Heliumplasma hoher Dichte und Temperatur

Abstract

The density and temperature in a stationary, magnetically stabilized He arc plasma are determined. The axial temperatures measured are between 200000°K and 400000°K, depending on the discharge current. The electron densities are found to be ne = 1.5 × 1016 cm-3, this value being constant over the arc radius. These measurements yield very steep radial pressure gradients and axial pressures of up to 1 atm. The pressure profiles are dealt with quantitatively. It is shown that the pressure build-up is governed essentially by a thermomagnetic effect familiar in solid state physics, namely the Nernst effect. The theory of this effect readily explains why the electron density is constant over the radius.