Branching ratios of multiply charged ions formed through photoionization of Kr 3d, 3p and 3s sub-shells using a coincidence technique

Multiple-charged Kr ions have been studied using monochromatized synchrotron radiation combined with a coincidence technique. The multiple-charged ions formed through ionization of the inner sub-shells were detected by a time-of-flight mass analyser and the photoelectrons emitted from those orbitals were observed by a cylindrical mirror electron energy analyser. The coincidence measurement between the energy-selected photoelectron and the photoion specified the individual multiple ionization channels of Kr. The Kr 3d ionization produces doubly and triply charged ions. The Kr 3p ionization mainly yields triply charged Kr ions via M 23 M 45 N 23 Coster–Kronig decays, and the M 23 M 45 N 1 decays generate considerably quadruply charged ions. The 3s ionization significantly produces quadruply charged ions via super-Coster–Kronig decays with successive Auger transitions.