Transfer excitation in low-energy (keV amu⁻¹) multiply charged ion-atom collisions

Evidence for simultaneous electron excitation and capture is found in collisions between Ne 7+ (1s 2 2s) ions and He atoms. Population of the Ne 6+ (1s 2 2p3l) states is found to amount to up to 16% of the total electron capture cross section. Unambiguous identification of the transfer excitation channel has been obtained with a new technique where charge states of both projectile and target as well as energy gain and scattering angle are all simultaneously determined. The relative importance of 'correlated' electron processes is discussed in view of the presently available data.