Electron capture and excitation in He²⁺-Na collisions

State-selective charge transfer and target excitation in collisions of He2+ ions with Na has been studied by means of far ultraviolet and visible light spectroscopy. Generally, the experimental results confirm the theoretical predictions by Shingal, Noble and Bransden for electron capture and for the dominant excitation channel, Na(3p). However in the lower half of the impact energy range studied, 2-9 keV amu-1, discrepancies in energy dependence and absolute magnitude (up to a factor of approximately 6) are found for the Na(4p) and Na(4d) excitation channels.