Statistical Study of Electron Avalanches in Gaseous Discharge

Size distributions of electron avalanches were observed at a potential several percent below the breakdown value. The distributions at low pressure discharge agreed well with Wijsman's formula which was derived from the Townsend theory in the absence of space charge effect. The distributions at atmospheric pressure, however, are different from this formula in that the pulses had a tendency to become uniform in size. This tendency was accounted by the space charge effect. In connection with these mesurement the pulses of corona discharges were also measured.