Observation of the relaxation of the excited core-hole states in solids prior to the core-hole decay by the coincidence photoelectron spectroscopy

Highlights: • The coincidence L3 PES spectrum of Co is analyzed. • The delocalization time of a valence hole in Co is determined. • The coincidence L3 PES spectrum of Ni metal is analyzed. - Abstract: The L3 photoelectron spectroscopy (PES) spectrum of Co measured in coincidence with the L3-VV Auger-electron spectroscopy (AES) peak is analyzed by a many-body theory. The spectrum provides hard evidence that the L3 PES shakeup/off satellite relaxes fully to the L3 PES main line prior to the L3-hole decay. This is in accord with the experimental finding that except for a very weak AES satellite, there is no appreciable line shape change between the singles (noncoincidence) L3-VV AES spectrum of Co measured just above the L3 PES main-line ionization edge and the one far above the L1 -level ionization edge. The delocalization time of the valence hole created together with the core-hole in the atomic L shell in Co is shorter than the core-hole lifetime