Benchmark nonperturbative calculations for the electron-impact ionization of Li(2s) and Li(2p) - art. no. 213201

Three independent nonperturbative calculations are reported for the electro n-impact ionization of both the ground and first excited states of the neut ral lithium atom. The time-dependent close-coupling, the R matrix with pseu dostates, and the converged close-coupling methods yield total integral cro ss sections that are in very good agreement with each other, while perturba tive distorted-wave calculations yield cross sections that are substantiall y higher. These nonperturbative calculations provide a benchmark for the co ntinued development of electron-atom experimental methods designed to measu re both ground and excited state ionization.