Université de Fribourg

Double K-shell photoionization and hypersatellite x-ray transitions of 12⩽Z⩽23 atoms

Hoszowska, Joanna ; Dousse, Jean-Claude ; Cao, Wei ; Fennane, Karima ; Kayser, Yves ; Szlachetko, Monika ; Szlachetko, Jakub ; Kavčič, Matjaz

In: Physical Review A, 2010, vol. 82, no. 6, p. 063408

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...

Université de Fribourg

First observation of two-electron one-photon transitions in single-photon K-Shell double ionization

Hoszowska, Joanna ; Dousse, Jean-Claude ; Szlachetko, Jakub ; Kayser, Yves ; Cao, Wei ; Jagodziński, P. ; Kavčič, Matjaz ; Nowak, S. H.

In: Physical Review Letters, 2011, vol. 107, no. 5, p. 053001

xperimental evidence for the correlated two-electron one-photon transitions (1s⁻²→2s⁻¹2p⁻¹) following single-photon K-shell double ionization is reported. The double K-shell vacancy states in solid Mg, Al, and Si were produced by means of monochromatized synchrotron radiation, and the two-electron one-photon radiative transitions were observed by using a wavelength dispersive...

Université de Fribourg

Single-photon double K-shell ionization of low-Z atoms

Hoszowska, Joanna ; Kheifets, A. S. ; Dousse, Jean-Claude ; Bray, Igor ; Cao, Wei ; Fennane, Karima ; Kayser, Yves ; Kavčič, Matjaz ; Szlachetko, Jakub ; Szlachetko, Monika

In: Journal of Physics: Conference Series, 2010, vol. 212, no. 1, p. 012006

The photon energy dependence of the double K-shell ionization of light atoms is reported. Experimental double-to-single photoionization cross section ratios for Mg, Al, Si and Ca were obtained from measurements of high-resolution x-ray emission spectra. The double photoionization (DPI) cross-sections for K-shell hollow atom production are compared to convergent close-coupling calculations (CCC)...

Université de Fribourg

Double K-shell photoionization of low-Z atoms and He-like ions

Hoszowska, Joanna ; Kheifets, A. S. ; Berset, Michel ; Bray, I. ; Cao, Wei ; Dousse, Jean-Claude ; Fennane, Karima ; Kavčič, M. ; Kayser, Yves ; Szlachetko, Jakub ; Szlachetko, Monika

In: The European Physical Journal: Special Topics, 2009, vol. 169, no. 1, p. 23-27

We report on the investigation of the photon energy dependence of double 1s photoionization of light atoms and compare the cross sections for hollow atom and He-like ion production. Measurements of the Kα hypersatellite x-ray spectra of Mg, Al, and Si were carried out using the Fribourg high-resolution x-ray spectrometer installed at the ID21 and ID26 beam lines at the ESRF. The...

Université de Fribourg

Double K-shell ionization of Al induced by photon and electron impact

Fennane, Karima ; Dousse, Jean-Claude ; Hoszowska, Joanna ; Berset, Michel ; Cao, Wei ; Maillard, Yves-Patrick ; Szlachetko, Jakub ; Szlachetko, Monika ; Kavčič, M.

In: Physical Review A, 2009, vol. 79, no. 3, p. 032708

This paper reports on the investigation of the double K-shell ionization of metallic aluminum induced by photon and electron impact. The experimental method consisted to measure the Kα hypersatellite spectra resulting from the radiative decay of double 1s vacancy states by means of high-resolution x-ray spectroscopy using a Bragg-type von Hamos crystal spectrometer....

Université de Fribourg

Separation of two-electron photoexcited atomic processes near the inner-shell threshold

Kavčič, M. ; Žitnik, M. ; Bučar, K. ; Mihelič, A. ; Štuhec, M. ; Szlachetko, Jakub ; Cao, Wei ; Mori, R. Alonso ; Glatzel, P.

In: Physical Review Letters, 2009, vol. 102, no. 14, p. 143001

By means of a high resolution resonant inelastic x-ray scattering spectroscopy, we have for the first time separated spectral features pertaining to different two-electron atomic processes in the vicinity of an inner-shell threshold. Contributions of shakeoff, shakeup, and resonant 1s3p double excitations were extracted from the Ar KM-M2,3M...

Université de Fribourg

Physical mechanisms and scaling laws of K-shell double photoionization

Hoszowska, Joanna ; Kheifets, A. K. ; Dousse, Jean-Claude ; Berset, Michel ; Bray, I. ; Cao, Wei ; Fennane, Karima ; Kayser, Yves ; Kavčič, Matjaz ; Szlachetko, Jakub ; Szlachetko, Monika

In: Physical Review Letters, 2009, vol. 102, no. 7, p. 073006

We report on the photon energy dependence of the K-shell double photoionization (DPI) of Mg, Al, and Si. The DPI cross sections were derived from high-resolution measurements of x-ray spectra following the radiative decay of the K-shell double vacancy states. Our data evince the relative importance of the final-state electron- electron interaction to the DPI. By comparing the double-to-single...