Inner-shell photodetachment of Li^-

Abstract

Absolute cross section for photodetachment of Li- ions near the 1s threshold leading to Li+ formation has been measured by overlapping a beam of Li- ions with synchrotron radiation from an undulator. Multiple excitation to the core-excited Li 1s(2s2p 3P) 2P and Li 1s(2p3s 3P) 2P states, i.e. conjugate shakeup, is found to be much stronger than observed for any neutral atom or positive ion, reflecting the dominant influence of electron correlation for negative ions. The cross section for multiple excitation is significantly larger than for single excitation.