Fast Time Analysis of Intermittent Point-to-Plane Corona in Air. II. The Positive Pre-Onset Streamer Corona

Abstract

Analysis has been made of pre‐onset streamers in room air at 760 mm with fast oscilloscope using both photomultiplier and electrical registration. The shape of the photon pulse observed by W. N. English is confirmed, and is interpreted. Current and luminosity roughly parallel each other in the streamer. Tip velocities ranged from 6×10⁷ cm/sec to 2×10⁷ cm/sec being highest near the point. The luminosity is constant over the path except at the very beginning and at the end of the path suggesting that ionization is also constant. The net number of positive ions left behind per cm length of streamer in consequence of the electron flow into the point is constant, and has been measured to be about 8×10⁹ ions per cm in general agreement with earlier work. Lateral deflection of the ends of streamer tracks by space charge left behind from previous streamers was directly observed.