Vacancy rearrangement processes in multiply ionized atoms

Abstract

We demonstrate that in order to interpret the x-ray satellite structure of Pd Lα1,2(L3M4,5) transitions excited by fast O ions, which was measured using a high-resolution von Hamos crystal spectrometer, the vacancy rearrangement processes, taking place prior to the x-ray emission, have to be taken into account. The measured spectra were compared with the predictions of the multi-configuration Dirac-Fock (MCDF) calculations using the fluorescence and Coster-Kronig yields which were modified due to a reduced number of electrons available for relaxation processes and the effect of closing the Coster-Kronig transitions. We demonstrate that the vacancy rearrangement processes can be described in terms of the rearrangement factor, which can be calculated by solving the system of rate equations modelling the flow of vacancies in the multiply ionized atom. By using this factor, the ionization probability at the moment of collision can be extracted from the measured intensity distribution of x-ray satellites. The present results support the independent electron picture of multiple ionization and indicate the importance of use of Dirac-Hartree-Fock wave functions to calculate the ionization probabilities.

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

“…The intensities provided by the fit were then corrected for the vacancy rearrangement processes and the modified fluorescence yields characterizing multiply ionized atoms (see Ref. [7]). From these corrected intensities which reflect the relative numbers of spectator holes at the collision time, the initial distributions of the L-and M -shell vacancies were determined.…”

Satellite and hypersatellite structure of Mα1,2 x‐ray transitions in thorium excited by fast oxygen ions

“…The vacancy rearrangement process, as we have demonstrated earlier, [ 32,33 ] can be described using a simplified approach adopting the Larkins statistical scaling [ 34 ] of Auger and Coster‐Kronig widths and the effect of closing of the Coster–Kronig transitions (see Ref. [33]) in multiple ionized atoms.…”

“…Using this assumption the evolution of vacancy distribution can be obtained by solving a system of the rate equations as it was discussed in Refs. [32, 33]. Details of calculations of the vacancy rearrangement are not discussed here, instead only the final results for the M‐shell will be described.…”

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.…”