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

Dissociation of chloromethanes upon resonant σ* excitation studied by x-ray scattering

Bohinc, R. ; Žitnik, M. ; Bučar, K. ; Kavčič, Matjaz ; Journel, L. ; Guillemin, R. ; Marchenko, T. ; Simon, M. ; Cao, Wei

In: The Journal of Chemical Physics, 2014, vol. 139, no. 13, p. 134302

The dissociation process following the Cl K-shell excitation to σ* resonances is studied by high resolution spectroscopy of resonant elastic and inelastic x-ray scattering on CH3Cl, CH2Cl2, CHCl3, and CCl4 molecules. Calculations employing the transition potential and Delta-Kohn-Sham DFT approach are in good agreement with the measured total fluorescence yield and show the presence of...

Université de Fribourg

Resonant inelastic x-ray scattering at the limit of subfemtosecond natural lifetime

Marchenko, T. ; Journel, L. ; Marin, T. ; Guillemin, R. ; Carniato, S. ; Žitnik, M. ; Kavčič, Matjaz ; Bučar, K. ; Mihelič, A. ; Hoszowska, Joanna ; Cao, Wei ; Simon, M.

In: The Journal of Chemical Physics, 2011, vol. 134, no. 14, p. 144308

We present measurements of the resonant inelastic x-ray scattering (RIXS) spectra of the CH3I molecule in the hard-x-ray region near the iodine L2 and L3 absorption edges. We show that dispersive RIXS spectral features that were recognized as a fingerprint of dissociative molecular states can be interpreted in terms of ultrashort natural lifetime of ∼200 attoseconds in the case of the iodine...

Université de Fribourg

Double L₃M ionization of Pd induced by impact with medium-energy electrons

Cao, Wei ; Dousse, Jean-Claude ; Hoszowska, Joanna ; Kavčič, Matjaz ; Kayser, Yves ; Schenker, Jean-Luc ; Žitnik, M.

In: Physical Review A: atomic, molecular and optical physics, 2011, vol. 83, no. 2, p. 022708

The electron-induced L₃M two-step double ionization cross sections of metallic Pd were determined experimentally for incident electron beam energies ranging from the double ionization threshold up to 18 keV. The double L₃M ionization cross sections were derived from the intensity ratios (ILαM:ILα) of the resolved M satellites to the parent diagram lines. The sample was...

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...