A study of high-current toroidal ring discharge

Abstract

A toroidal ring discharge has been studied in which the exciting primary is a metal coating on the outside of the torus. The waveforms of the currents and electric fields in the gas have been obtained, and the light from the discharge has been studied spectroscopically and with a photo-multiplier, the gases used being hydrogen and argon. Very large currents flow in the gas with peak amplitudes greater than 104 A. The current is in phase with the electric field, the exciting frequency being 150 kc./sec. Photographs of the discharge show a marked ‘pinch’ effect in argon. The method of Craggs & Hopwood (1947) has been applied to determine the ion concentrations from the broadening of the Balmer lines. Peak ion concentrations occur which are greater than the molecular concentra­ tions. High-frequency oscillations (1 to 5 Mc./sec.) occur in the gas and are thought to be plasma ion oscillations.