2011 Articles

Storage Ring Cross Section Measurements for Electron Impact Ionization of Fe12 + Forming Fe13 + and Fe14 +

Hahn, Michael; Grieser, M.; Krantz, C.; Lestinsky, M.; Muller, A.; Novotny, Oldrich; Repnow, R.; Schippers, S.; Wolf, A.; Savin, Daniel Wolf

We report electron impact ionization cross section measurements for electron impact single ionization of Fe12 + forming Fe13 + and electron impact double ionization of Fe12 + forming Fe14 +. These are the first electron impact ionization data for any Si-like ion uncontaminated by an unknown metastable fraction. Recent distorted wave calculations agree with our single ionization results to within ~15%. Double ionization is dominated by inner shell ionization of a 2l electron resulting in autoionization of a second electron as the inner shell hole is filled.