Université de Fribourg

Hypersatellite x-ray decay of $3d$ hollow-$K$-shell atoms produced by heavy-ion impact

Maillard, Yves-Patrick ; Dousse, Jean-Claude ; Hoszowska, Joanna ; Berset, Michel ; Mauron, Olivier ; Raboud, Pierre-Alexandre ; Kavčič, Matjaz ; Rzadkiewicz, J. ; Banaś, Dariusz ; Tökési, K.

In: Physical Review A, 2018, vol. 98, no. 1, p. 012705

We report on the radiative decay of double K-shell vacancy states produced in solid Ca, V, Fe, and Cu targets by impact with about 10 MeV/amu C and Ne ions. The resulting K hypersatellite x-ray emission spectra were measured by means of high- energy-resolution spectroscopy using a von Hamos bent crystal spectrometer. The experiment was carried out at the Philips variable energy cyclotron of...

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

High energy resolution measurements of the radiative decay of double K-shell vacancies in 20 ≤ Z ≤ 29 elements bombarded by fast C and Ne ions

Dousse, Jean-Claude ; Maillard, Yves-Patrick ; Berset, Michel ; Castella, D. ; Hoszowska, Joanna ; Kavčič, Matjaz ; Kobal, M. ; Mauron, Olivier ; Muehleisen, A. ; Raboud, Pierre-Alexandre ; Rzadkiewicz, J. ; Tökési, K. ; Zorko, B.

In: Journal of Physics: Conference Series, 2015, vol. 635, no. 2, p. 022054

We report on high energy resolution measurements of the Kα hypersatellite x-ray spectra of Ca, V, Fe and Cu induced by impact with 144 MeV C and 180 MeV Ne ions.

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

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...

Université de Fribourg

Double 1s shell ionization of Si induced in collisions with 1–3-MeV protons

Kavčič, Matjaz ; Tökési, K.

In: Physical Review A, 2005, vol. 72, p. 062704

The double 1s ionization of Si induced in collisions with protons was studied by measuring the K x-ray emission of a solid Si target ionized by the impact of 1–3-MeV protons. In order to resolve the hypersatellite contributions corresponding to the radiative decay of the double 1s vacancy state, a high-resolution crystal spectrometer was employed yielding sub-eV energy...