Autoionization widths of doubly excited states for highly ionized systems: An application of the Stieltjes moment theory

Processes such as dielectronic recombination or excitation-autoionization, which involve doubly excited states, are important for understanding the kinetics of laboratory plasmas. Theoretical studies of these processes require knowledge of Auger as well as radiative decay rates for the intermediate states involved. We have applied Stieltjes moment theory techniques to the problem of calculating autoionization widths for the (3l3l') doubly excited states of Kr²⁵⁺ (sodiumlike krypton). Configuration-interaction wave functions were used to describe the resonances as well as the continuum. We have explored the effects of intermediate coupling, configuration mixing, and orbital relaxation on the calculated autoionization rates.