Diagram, valence‐to‐core, and hypersatellite Kβ X‐ray transitions in metallic chromium

Abstract

We report on measurements of the Kβ diagram, valence‐to‐core (VtC), and hypersatellite X‐ray spectra induced in metallic Cr by photon single and double K‐shell ionization. The experiment was carried out at the Stanford Synchrotron Radiation Lightsource using the seven‐crystal Johann‐type hard X‐ray spectrometer of the beamline 6‐2. For the Kβ diagram and VtC transitions, the present study confirms the line shape features observed in previous works, whereas the Khβ hypersatellite transition was found to exhibit a complex spectral line shape and a characteristic low‐energy shoulder. The energy shift of the hypersatellite relative to the parent diagram line was deduced from the measurements and compared with the result of extensive multiconfiguration Dirac–Fock (MCDF) calculations. A very good agreement between experiment and theory was found. The MCDF calculations were also used to compute the theoretical line shape of the hypersatellite. A satisfactory agreement was obtained between the overall shapes of the experimental and theoretical spectra, but deviations were observed on the low‐ and high‐energy flanks of the hypersatellite line. The discrepancies were explained by chemical effects, which were not considered in the MCDF calculations performed for isolated atoms.