The Calculation of Auto-Ionization Probabilities - I: Perturbation Methods with Application to Auto-Ionization in Helium

Abstract

Earlier calculations for auto-ionization probabilities using time-dependent perturbation methods are critically reviewed and improved methods are developed. These are applied to the calculation of the auto-ionization probabilities for certain doubly excited states of helium. The calculated probabilities lie in general between 1014 and 1015 sec-1, confirming previous results. The evaluation of certain integrals involving coulomb functions is described in an appendix.