Autoionizing Rydberg series in photoionization cross section of alkali atoms

摘要

New results of many electron calculations of outer np~6 shell photoionization cross section for neutral potassium, rubidium and caesium are presented. The special interest is devoted to autoionizing ns → (n+1)p resonances. The resonance structure associated with excitation of autoionizing states has been studied. Interelectron correlations are shown to play a crucial role describing the resonance parameters. The correlations are taken into account by means of the Random Phase Approximation with Exchange (RPAE) and the Many Body Perturbation Theory (MBPT). The differences in behavior of electrons with opposite spin projections are traced.