A Scattering Approach to the Decay of Metastable States

Abstract

The time-independent multichannel scattering theory is formulated in a way which makes it appropriate for the study of the decay of autoionizing and inner-shell vacancy states. A general interpretation of the parameters in the Fano profile is given and the concept of decay is introduced for both autoionizing and inner-shell vacancy states in a transparent manner. The theory is applied to a study of the influence of photon-electron coupling effects on the radiative and nonradiative decay probabilities. A generalization which includes post-collision interactions in inner-shell ionization is also presented.