Khα1,2 X-ray hypersatellite line broadening as a signature of K-shell double photoionization followed by outer-shell ionization and excitation

We propose a novel approach for the theoretical analysis of the photoinduced high-resolution Khα1,2 x-ray hypersatellite spectra, which allows us to obtain reliable values of lifetimes of the doubly K-shell ionized states and fundamental information about the relative role of K-shell double photoionization (DPI) mechanisms. It is demonstrated for the first time that the Khα1,2 hypersatellite natural line broadening observed for selected metal atoms with 20≤Z≤30 can be well reproduced quantitatively by taking into account the influences of the open-shell valence configuration (adopted from predictions of the band-structure method) and the outer-shell ionization and excitation following the DPI process.