Population of individual Ne1s−1npRydberg states measured across the1sionization threshold and the evolution of shake-up into shake-down

Abstract

New high-resolution experimental results on Ne $1s$ near-threshold photoionization with subsequent decay into a $2{p}^{4}(^{1}D_{2}){n}^{\ensuremath{'}}p$ or $2{p}^{4}(^{1}D_{2}){\ensuremath{\epsilon}}^{\ensuremath{'}}p$ state are presented. The population of Rydberg states up to ${n}^{\ensuremath{'}}=12$ is determined as a function of excess energy. These data allow one to track in detail the transition from resonant Auger decay going along with shake-up of the spectator electron to shake-down and photoionization with recapture of the photoelectron. Results are in good agreement with a time-dependent quantum mechanical theory of Auger decay in the presence of a slow photoelectron.