Measurement of the cross section for electron-impact ionization ofXe6+ions

Abstract
The absolute cross section for electron-impact ionization of Xe6+ has been measured from below threshold to 1500 eV with the Oak Ridge National Laboratory crossed-beams apparatus. Excitation of inner-shell electrons to autoionizing states is found to contribute up to a factor of 10 more than direct processes to the single-ionization cross section, and indirect effects dominate the measurement over the entire energy range studied. Good agreement is found with distorted-wave excitation calculations added to Lotz direct-ionization predictions.