Optical Quenching of Metastable Hydrogen

This paper discusses the theory of the quenching of a metastable atomic state by means of a high-frequency electromagnetic wave. The particular problem for which numerical results are presented is that of the quenching of the metastable $2S$ state of atomic hydrogen by means of the light from a ruby laser. The general theory is worked out both by means of the quantum electrodynamical perturbation theory and by means of a strong signal theory. The relation between these two techniques is discussed.