High-resolution X-ray study of the multiple ionization of Pd atoms by fast oxygen ions

Abstract

Abstract. The multiple ionization of the L-and M -shells of Pd by fast oxygen ions has been studied by measuring with high-resolution the satellite structures of the Lα1,2 X-ray transitions. Relativistic multiconfiguration Dirac-Fock (MCDF) calculations were used to interpret the complex X-ray spectrum, allowing to derive the number of L-and M -shell spectator vacancies at the moment of the X-ray emission. After correcting these numbers for the atomic vacancy rearrangement processes that take place prior to the X-ray emission, the ionization probabilities corresponding to the collision time were obtained. The latter were compared to predictions of the semiclassical approximation (SCA) and the geometrical model. The SCA calculations were performed using relativistic hydrogenic and self-consistent Dirac-Hartree-Fock (DHF) electronic wave functions. It was found that the use of the more realistic DHF wave functions in the SCA calculations leads to a much better description of the measured ionization probabilities for both the Land M -shells.

Satellite and hypersatellite structures ofLα1,2andLβ1x-ray transitions in mid-Czarnota1, Banaś2, Berset3 et al. 2013Phys. Rev. ASelf Cite

“…, (21) where the factorials are the statistical weights corresponding to the binomial distribution of the spectator vacancies with the constraint that for the diagram or M-satellite transition the single L-shell vacancy should be located in the L 3 subshell, whereas for the hypersatellite transition at least one vacancy has to be located in the L 3 subshell and another one in any other L subshell. As shown by Eq.…”

“…20] and calculated [Eq. (21)] values of the R ratios were directly compared using the theoretical predictions of the SCA-HYD and SCA-DHF models. Second, using the SCA-DHF calculations which provide for the ratio R values which are, except for Zr, closer to the experimental ones, the L-shell ionization probabilities for central collisions p L (0) were determined by solving the equation R[p L (0)] = R exp (see Fig.…”

“…Such measurements of heavy-ion induced K-hypersatellites were found to be a sensitive tool for studying the relativistic and quantum electrodynamics (QED) effects in atoms [16] and the dynamics of the multiple ionization of atoms by heavyion impact [17][18][19]. The observation of heavy-ion induced Lshell hypersatellites and their interpretation in terms of MCDF calculations were reported only recently [20,21].…”

“…The experimental data, interpreted in terms of the relativistic multiconfiguration Dirac-Fock (MCDF) calculations, reveal that the observed x-ray spectra have complex structures characterized by numerous and partly overlapping x-ray satellite and hypersatellite lines. We present here systematic investigation of L-shell x-ray hypersatellite transitions in mid-Z elements, while some preliminary results concerning palladium were already presented earlier in shorter papers [20,21]. In general, the observed fine details of the measured x-ray satellite and hypersatellite x-ray spectra are important to probe the goodness of atomic structure calculations [29].…”

Calculations with spectroscopic accuracy for energies, transition rates, hyperfine interaction constants, and Landé g -factors in nitrogen-like Kr XXX

“…Calculations are performed using the MCDF method [28][29][30][31][32][33] implemented in the latest version of the GRASP2K code [34], in which higher order relativistic corrections arising from the Breit interaction (BI) and quantum electrodynamics (QED) effects are included within the RCI procedure.…”