New high-resolution measurements of doubly excited states of Li⁺

Abstract

We present new results for the doubly excited states Li+(nln´l´) of singly ionized lithium which arise from the measurements of the Auger decay of these states to Li++ ground state ions. Primary excitation of the doubly excited states is achieved by photon impact on neutral lithium atoms and therefore the experiment probes directly the double-shakeup photoionization process h+LiLi+**+e-. Detection of the individual Li+ Auger decay lines provides information on the energies and widths of many doubly excited levels of the ion, including the lowest lying (3l,3l´) state. Classifications are made using recent theoretical calculations.