Features of initiating the hollow cathode effect in a glow discharge electrode system with an extended cathode gap

The results of studies of the influence of the cathode-gap dimensions on the initiation of the hollow-cathode effect in a glow-discharge system with an extended rectangular hollow cathode are presented. It has been established that the threshold current for the transition of the discharge to the combustion mode with a hollow cathode is determined by the size of the cathode gap. With a decrease in the width of the slot, the threshold current increases disproportionately; with an increase in the longitudinal size of the slot, this current sharply decreases.