Post collision interaction in the L₃-M_4,5M_4,5 Auger spectra in solid state copper

A modern, free atom, angle dependent post collision interaction (PCI) model has been applied to the L₃-M_4,5M_4,5 Auger decay of Copper. The model predicts that the magnitude of PCI is strongly dependent on the type of atomic excitation method employed. For electron impact excitation, the magnitude of PCI is amplified due to the presence of scattered electrons in the reaction zone. The energy distribution between the ejected and scattered electrons for electron excitation is the main factor that determines the magnitude of PCI in Copper. In comparison, the model predicts that for photon excitation, such as a synchrotron radiation source, for the same Auger process, produces PCI effects which are smaller in magnitude. The model calculations show a marked improvement in fitting experimental PCI data from the L₃-M_4,5M_4,5 Auger decay of Copper when compared to a previous attempt [T. Jach, C.J. Powell, Phys. Rev. Lett. 46 (1981) 953]. PCI depends on the kinematics, hence energy distribution of the emitted charges. This energy distribution is expected to be different for the solid state compared to the free atom case. The free atom PCI models do not take into account inelastic and elastic scattering of the emitted charges. Secondary electron emission due to electron-electron inelastic scattering is one effect that may increase the magnitude of PCI in non-coincidence Auger spectra of Copper.