Multi-coincidence in cascade Auger decay processes

Abstract

Two-electron emission following inner shell ionization of rare-gas atoms by synchrotron radiation has been investigated experimentally with a magnetic bottle electron time of flight spectrometer. The detection in coincidence of a photoelectron with all Auger electrons allows a complete understanding of inner shell hole decay. This method has been applied to the study of single and double Auger decays following Xe 4d, Ar 2p and Kr 3d inner shell ionization. The double Auger decay scheme reveals direct double Auger process but is dominated by cascade processes involving inner-valence electrons in a first step followed by autoionization. Post collision interaction (PCI) associated to distorted Auger spectra and double photoionization paths in the vicinity of Xe 4d threshold, is also discussed.