Multiconfiguration Dirac-Fock calculations with the inclusion of the transverse (Breit) interaction and QED corrections have been carried out for Pd, Sn, Tb, Ta, Pb, and Th in order to obtain positions and intensities of various electric dipole, electric quadrupole, and magnetic dipole K x-ray diagram lines and of their KL 1 satellites. Theoretically constructed stick spectra have been presented together with synthesized spectra (the sum of the Lorentzian natural line shapes) for each studied element. Taking into account the existence of an L-shell hole in the 2s or 2p subshell, the effect of additional L-shell ionization on the shapes and structure of the K x-ray spectra has been examined. It has been observed that generally with increasing atomic number Z the shapes of particular satellite line groups tend to become smoother and to differ less from the shapes of appropriate diagram lines. Relations between the values of energy shifts of various satellite lines for each element and the changes of these relations with Z have also been studied. Additionally, the relations between the intensities of different diagram lines for each element have been systematically analyzed, likewise the changes with Z of the role of particular diagram lines. This study can be helpful in reliable and quantitative interpretation of many experimental K x-ray spectra of Pd, Sn, Tb, Ta, Pb, and Th induced in collisions with various projectiles.
Multiconfiguration Dirac–Fock calculations (with the inclusion of the transverse Breit interaction and QED corrections) have been performed for various Pb K x-ray lines. The calculated positions and intensities of many electric dipole, electric quadrupole and magnetic dipole KL0M1 and KL1M0 x-ray satellite lines have been analysed. On the basis of theoretically constructed stick and synthesized (the sum of the Lorentzian natural line shapes) K x-ray spectra, the effect of the additional single ionization of different subshells of the M shell on the shapes and structure of Pb K x-ray spectra has been investigated and compared with the effect of the single L-shell ionization. It has been found that in the KL0M1 satellite spectra the sticks are less scattered and the shapes of the bands are narrower and smoother than in the KL1M0 spectra. The much weaker influence of an additional M-shell hole on the K x-ray spectra than of an L-shell hole is also reflected in very small values of the energy shifts (with respect to the corresponding diagram lines) of the KL0M1 satellite lines in comparison with those of the KL1M0 lines. This study provides an exhaustive set of data, enabling not only the correct quantitative analysis of many experimental Pb K x-ray spectra (induced in collisions with various projectiles), but also predictions concerning the K x-ray spectra of multiply ionized Pb or other heavy atoms, which can be helpful in designing new experiments.
Simulations of the shapes of Pb K x‐ray spectra have been performed for an experimental situation in which single and double L‐ and M‐shell ionization (apart from the single K‐shell ionization) of target atoms occurs. The simulations are based on the results of the calculations of the energies and probabilities of various Pb K x‐ray transitions, done with the multiconfiguration Dirac–Fock (MCDF) method with the inclusion of the transverse (Breit) interaction and quantum electro dynamic (QED) corrections. It has been found that most contributions to the simulated spectra considerably overlap other contributions. Thus, their extraction from the measured spectra, which provides data about the L‐ and M‐shell ionization probability in a collision process, will only be possible using the results of theoretical studies. Our studies can be crucial in both analysis of a number of observed Pb K x‐ray spectra and in designing new experiments concerning the K x‐ray spectra of multiply ionized heavy atoms induced in collisions with various light or heavy projectiles of different energies. Copyright © 2007 John Wiley & Sons, Ltd.
Predictions about the shapes of the K x-ray spectra of medium-Z and heavy atoms have been made on the basis of the results of theoretical multiconfiguration Dirac–Fock calculations (with the inclusion of the transverse Breit interaction and QED corrections) for various KL0M1 x-ray satellite lines of Pd, Tb, Ta and Th. The construction of theoretical stick and synthesized (the sum of the Lorentzian natural line shapes) K x-ray spectra (including also diagram and KL1M0 satellite lines) has enabled foreseeing such details of experimental spectra as the overlapping and visibility of particular groups of lines. The energy regions possibly best for the extraction of the satellite contributions in the measured K x-ray spectra have been indicated for each studied element. The effect of additional single ionization of the different subshells of the M shell on the structure and shapes of the spectra of various K x-ray lines has been investigated in detail for Pd, Tb, Ta and Th. It has been found that in the KL0M1 satellite spectra the shapes of the bands mainly resemble the shapes of the corresponding K x-ray diagram lines (but they are wider than the latter). For each element, the biggest average energy shifts with respect to the diagram lines are observed for a given kind of the KL0M1 lines mostly in the case of removing a 3p electron in the initial state, whereas the smallest shifts are caused by removing a 3d electron. Our study can enable the correct quantitative interpretation of the K x-ray spectra of different multiply ionized medium-Z and heavy atoms (induced in collisions with light or heavy ions) and can be instrumental in planning various new experiments involving the determination of the M- and L-shell ionization probability.
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