Dielectronic recombination from the ground and excited states of Li

Abstract Dielectronic recombination (DR) was investigated for Li + + e − collisions using the electron cooler at the Indiana University Cyclotron Facility (IUCF). For Li + (1s 2 ) ions, DR is expected to occur for relative energies E rel between 50–60 eV, and for metastable Li + (1s2s) DR should occur for E rel E rel near zero, radiative recombination (RR) (inverse photoelectric effect) is expected. This work is an extension of our previous work for He + ions. These light He + and Li + ions pose stringent tests of DR theory because the electron-electron interaction, which mediates DR, is stronger compared to the electron-nucleus interaction than is it for heavier ions. Additionally, the electron coupling in two-electron Li + gives rise to angular momentum configurations different from those in He + . Preliminary results of recent measurements at IUCF, where DR was observed for both ground-state and metastable Li + ions, are presented.