Effect of conductive screens on the stabilization of plasma channels with currents of hundreds kAmps

The problem of plasma structure stabilization recently has received considerable attention for low and high temperature plasma applications, in particular in fusion experiments, and in order to cope with the problem different special configurations of current and magnetic systems are developed and deployed. However, the available solutions require construction of complex magnetic fields and consume considerable amounts of energy. With respect to thyratrons, which operation is characterized by the presence of normally several high current plasma channels, this issue has not been yet studied thoroughly. Based on experimental data, we analyzed the results of the influence of an external conductive shield on stabilization of plasma channels in high-power pseudospark switches with reentrant and classic design. Both non-ferrous and ferrous shields have been tested. The preliminary calculation of the magnetic field distribution is presented. This research is a part of a work on improvement of switching capabilities of thyratrons used for transferring currents up to hundreds kA with switching energy more than 50 kJ.