Observation of dielectronic recombination through two-electron–one-photon correlative stabilization in an electron-beam ion trap

Dielectronic recombination (DR) for He-like ${\mathrm{Ar}}^{16+}$ through both one-electron–one-photon and two-electron–one-photon (TEOP) stabilizations of Li-like states was studied with an electron-beam ion trap (EBIT). It turned out that this is an excellent method to investigate TEOP transitions. Its advantages are a high branching ratio for the TEOP transition and clean conditions under which spectator electrons are controlled. Further, state- and configuration-resolved KLL DR cross sections were obtained due to the unsurpassed electron energy resolution achieved in the EBIT in the energy range around 2 keV.