The influence of vaporization upon the roots of a high current arc. II

The root of an argon are was stabilized by strong cooling of the graphite cathode; both the composition and the temperature of the plasma at the arc root were determined spectroscopically. The measurements of the absolute intensities of two CI and two CII lines revealed that the plasma is composed almost entirely of atomic carbon. Immediately in front of the cathode a temperature of 12000 K was measured and the degree to which the gas was ionized was found to be 30%. The velocity of the plasma was 300 m/s. This work is based upon material presented in the final report “Basic research programme for plasma technology, high-pressure arcs in SF₆” to the Federal Department of Research and Technology, Fed. Rep. Germany.