BREAKDOWN INITIATION AND DEVELOPMENT IN THE RANGE TO THE LEFT OF THE PASCHEN MINIMUM

摘要

This paper investigates mechanisms of gas breakdownrninitiation and development in the range to the left of thernPaschen minimum. Statistical analysis of experimentalrnresults, obtained under closely controlled laboratoryrnconditions, shows that the region left of the Paschenrnminimum can be divided into three subregions. It isrndemonstrated that in the first subregion, just next to thernPaschen minimum, breakdown occurs by way of the edgernmechanisms, often interpreted as the anomalous Paschenrneffect. In the next subregion, breakdown arises throughrnthe vacuum avalanche mechanism, while in the thirdrnsubregion it occurs via the vacuum cathode emissionrnmechanism.