The Secondary Electron Resonance Mechanism of Low-Pressure High-Frequency Gas Breakdown

Abstract

Breakdown field strengths have been measured in air and hydrogen at pressures of the order of 1 micron Hg and frequencies from 25 to 90 Mc/sec between flat metal electrodes at separations from 1 to 4 cm. By suddenly applying a high voltage and then lowering it slowly an upper breakdown curve has been observed. This new curve can be combined with the lower breakdown curve and cut-off frequency such as reported previously by the Guttons, and by Gill and von Engel to form the boundaries of a breakdown region in the frequency-field strength domain. The simple secondary electron resonance theories developed by Danielsson and Gill and von Engel have been extended by the semi-empirical determination of minimum and maximum limiting values of the electron-emission phase angle, a minimum limiting value of electron arrival energy, and a ratio between electron arrival and emission velocities.