Characteristics of single capture nl distributions and double capture probabilities in slow collisions of Al13+, Al12+and Ne9+ions with two-electron targets (He, H2)

Relative intensities of Lyman X-rays consecutive to one- or two-electron capture have been measured for collisions of 4 keV u -1 Al 13+ , Al 12+ , Ne 9+ ions with He and H 2 targets. A method is presented to extract separate information on single and double transfer processes. Preferential n states, proportion of p substrates and mean l values populated by single capture are measured, together with double capture probabilities. Comparison of experimental results with theoretical predictions for one-electron systems with near-crossing radii suggest that the location of these crossings may be more important than target internal structure to determine final l distributions. Finally, for the investigated systems with different ionic charges but near-crossing radii, double capture probabilities are found to be quite similar.