In: Review of Scientific Instruments, 2013, vol. 84, no. 9, p. 093104
We report on a high-resolution transmission-type curved crystal spectrometer based on the modified DuMond slit geometry. The spectrometer was developed at the University of Fribourg for the study of photoinduced X-ray spectra. K and L X-ray transitions with energies above about 10 keV can be measured with an instrumental resolution comparable to their natural linewidths. Construction details...
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In: Review of Scientific Instruments, 2012, vol. 83, no. 10, p. 103105
We report on the design and performance of a wavelength-dispersive type spectrometer based on the von Hamos geometry. The spectrometer is equipped with a segmented-type crystal for x-ray diffraction and provides an energy resolution in the order of 0.25 eV and 1 eV over an energy range of 8000 eV–9600 eV. The use of a segmented crystal results in a simple and straightforward crystal...
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In: Journal of Electron Spectroscopy and Related Phenomena, 2012, p. -
The mechanisms leading to the production of hollow K shell atoms via single photon impact were investigated for a variety of light elements with 12 ≤ Z ≤ 23. The double 1s vacancy states were produced by irradiating the samples with intense monoenergetic synchrotron radiation beams. The double-to-single K-shell photoionization probabilities...
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In: X-Ray Spectrometry, 2012, vol. 41, no. 2, p. 98-104
We report on the surface-sensitive grazing emission X-ray fluorescence technique combined with synchrotron radiation excitation and high-resolution detection to realize depth-profile measurements of Al-implanted Si wafers. The principles of grazing emission measurements as well as the benefits offered by synchrotron sources and wavelength-dispersive detection setups are presented. It is shown...
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In: Physical Review Letters, 2011, vol. 107, no. 7, p. 073001
We propose a novel approach for the theoretical analysis of the photoinduced high-resolution Khα1,2 x-ray hypersatellite spectra, which allows us to obtain reliable values of lifetimes of the doubly K-shell ionized states and fundamental information about the relative role of K-shell double photoionization (DPI) mechanisms. It is demonstrated for the first time that the...
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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...
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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...
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In: Physical Review A, 2011, vol. 83, no. 4, p. 042513
The KMM radiative Auger (RA) x-ray spectra of solid Ca were induced by monochromatic synchrotron radiation and measured with a high-resolution von Hamos bent crystal spectrometer. Two excitation energies were employed, one in the near K threshold region and the second well above the K absorption edge. The KMM RA spectral structure and relative intensity with respect to the diagram ...
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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...
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In: Physical Review A, 2010, vol. 91, no. 06, p. 064702
An observation of the internal structure of the L-shell hypersatellite x rays resulting from the one-photon decay of L⁻² double-vacancy states in palladium multiply ionized by oxygen ions is reported. The Pd L₃→M4,5 x-ray spectrum was measured with a von Hamos high-resolution crystal spectrometer. The complex shape of the observed spectrum could be interpreted in detail using...
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