Post-collision interaction in inner-shell ionisation and excitation of Ne K and Kr L3by electron impact

Abstract

The authors have measured the energy shifts in of the Ne KL23L23 (1D2) Auger line (ionisation energy EB(Ne K)=870.3 eV, level width Gamma (Ne K)=0.27 eV) and of the Kr L3M45M45 (1G4) Auger line (EB(Kr L3)=1678.4 eV, Gamma (Kr L3)=1.17 eV) in a wide range of excess energies E1 up to an electron impact energy Eo=10 keV. The small experimental error of the authors data reveals a functional behaviour of the post-collision interaction (PCI) shift in (E1) different from in =c Gamma E-n1. The PCI shift does not follow a monotonic decreasing function in (E1) for all excess energies E1 but remains constant above a certain excess energy /E1, with /E1(Ne K) approximately=1 keV and /E1(Kr L3) approximately=3.5 keV. The authors give arguments for a non-vanishing PCI at large excess energies in the electron impact ionisation and give values for the absolute PCI shift in approximately for at energies E1 larger than /E1: in approximately Ne K)=48+or-12 meV, in (Kr L3)=102+or-25 meV and in approximately (Ar L3)=22+or-6 meV for Ar L3, which was studied previously by Graf and Hink (1985).