Hoszowska, Joanna Dousse, Jean-Claude Cao, Wei Fennane, Karima Kayser, Yves Szlachetko, Monika Szlachetko, Jakub Kavčič, Matjaz 2010-12-16 Single-photon double K-shell ionization of low-Z neutral atoms in the range 12⩽Z⩽23 is investigated. The experimental method was based on measurements of the high- resolution Kαh hypersatellite x-ray spectra following the radiative decay of the K-shell double-vacancy states excited by monochromatic synchrotron radiation. The photon energy dependence of the double K-shell ionization was measured over a wide range of photon energies from threshold up to and beyond the maximum of the double-to- single photoionization cross section ratios. From the high-resolution x-ray emission spectra the energies and linewidths of the hypersatellite transitions, as well as the Kαh1:Kαh2 intensity ratios, were determined. The relative importance of the initial-state and final-state electron-electron interactions to the K-shell double photoionization is addressed. Physical mechanisms and scaling laws of the K-shell double photoionization are examined. A semiempirical universal scaling of the double- photoionization cross sections with the effective nuclear charge for neutral atoms in the range 2⩽Z⩽47 is established. application/pdf https://folia.unifr.ch/global/documents/305070 https://folia.unifr.ch/documents/305070/files/dou_dks.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevA.82.063408 info:eu-repo/semantics/openAccess License undefined Physical Review A. - 2010, vol. 82, no. 6, p. 063408 info:eu-repo/classification/udc/53 Double K-shell photoionization and hypersatellite x-ray transitions of 12⩽Z⩽23 atoms http://purl.org/coar/resource_type/c_6501