Thermionic research at Stresa: A review

At the recent International Conference on Thermionic Electrical Power Generation (Stresa, May 1968) a large number of research papers were presented which were devoted to an understanding of the thermionic diode. It is the purpose of the present paper to review the recent presentations at Stresa. It will be shown from these papers that in the 2½ years since the first International Conference, significant advances have been made in the physics of the cesium diode. In particular, these include new interpretations of current-voltage characteristics, the use of gases other than cesium, spectroscopic plasma diagnostics, diode probe studies, plasma-sheath studies, studies of ionization and recombination, and computer solutions for the diode. That they might be seen in context, brief reference is made to other recent publications. Papers devoted to surface phenomena are not discussed.