Charge-state yields in Ar following K-shell excitation

Total ion yield measurements following inner-shell ionization are commonly compared to absorption spectra because they manifest similar behavior. The individual charge-state yields can, however, give much more information, which can aid in identifying features in the absorption spectrum, as well as display qualitatively new behavior. Using time-of-flight mass spectrometry to study the K-shell ionizations of Ar we can trace the origin of prominent features in the absorption spectrum to a single-charge state, demonstrate the coupling of different charge states by the post-collision interaction (PCI), and trace the onset of multiple excitations at energies far above threshold