I. A. Krinberg
Irkutsk State University, Irkutsk, Russia
The expansion and heating of the cathodic plasma in a vacuum arc subjected to an axial magnetic field were studied theoretically. It is found that the imposition of the external field leads to the formation of the plasma channel of an invariable cross section and to an increase in the electron temperature and in the mean ion charge state if the Coulomb collision frequency becomes less than the electron gyrofrequency. The model calculations have been carried out for Al, Ta, Bi, and U-cathode at current range of 100—800 A and magnetic field strength varying from zero to 0.5 T. The calculated mean ion charge state agrees with experiments.
