Study of electronic excitation and electron capture processes in the collision between ground-state rubidium atoms and potassium ions by crossed beams

Abstract

Collisional processes between K ions and Rb (both in their ground state) have been studied using a crossed beam technique and measuring the decay fluorescence. Emissions corresponding to decay of the first excited state of Rb and the first two excited states of neutral K have been detected. For these, absolute total cross-section dependence on collision energy, branching ratios between J-states and true excitation cross-sections (from polarization measurements) have been determined, all in the 0.3–4.1 keV range. The results are interpreted using adiabatic potential energy curves calculated ab initio employing one-electron, non-empirical, relativistic pseudopotentials and including core polarisation.