Relativistic recoil, electron-correlation, and QED effects on the2pj-2stransition energies in Li-like ions

Abstract

The relativistic nuclear recoil, higher-order interelectronic-interaction, and screened QED corrections to the transition energies in Li-like ions are evaluated. The calculation of the relativistic recoil effect is performed to all orders in 1/Z. The interelectronic-interaction correction to the transition energies beyond the two-photon exchange level is evaluated to all orders in 1/Z within the Breit approximation. The evaluation is carried out employing the large-scale configurationinteraction Dirac-Fock-Sturm method. The rigorous calculation of the complete gauge invariant sets of the screened self-energy and vacuum-polarization diagrams is performed utilizing a local screening potential as the zeroth-order approximation. The theoretical predictions for the 2p j − 2s transition energies are compiled and compared with available experimental data in the range of the nuclear charge number Z = 10 − 60.

Relativistic configuration-interaction calculations of the energy levels of the 1s22l and 1s2l2l′Yerokhin1, Surzhykov2, Müller3 2017Phys. Rev. A3410333View full textAdd to dashboardCite

“…[32]. The rigorous QED calculations [7] provide results only for Z = 10 and 15 in the region of Z relevant for the present work. Because of this, we also compare our values against the MBPT results of Ref.…”

“…In order to establish the level of accuracy of the model QED operator approach in the region of low nuclear charges, we compared values obtained with the QEDMOD package with results of rigourous QED calculations for the 1s 2 2s and 1s 2 2p 1/2 states. Such calculations were accomplished for the lightest Li-like atoms within the NRQED approach [1] and for heavier Li-like ions within the all-order in Zα method [5,7]. The comparison is presented in Table II.…”

“…[1] for Li and Be + and from Ref. [7] for Mg 9+ and Ar 15+ . In order to obtain QED shifts to the total energies, we added results from Refs.…”

“…In the region of heavy ions, the best results are presently obtained within the alternative approach that accounts for all orders in the nuclear binding strength parameter Zα but expands in the electron-electron interaction parameter 1/Z. Calculations by this method were performed by Shabaev and coworkers [4][5][6][7] for the ground and first excited states of Li-like ions with Z ≥ 10. It is important to point out that both these methods were able to produce predictive results, i.e., their results contain estimates of theoretical errors obtained without referring to experimental data.…”

ris3: A program for relativistic isotope shift calculations

“…Shabaev and Artemyev [6] and, in an independent way, Palmer [7], derived these relativistic corrections to the mass shift. Since then several papers have shown the importance of such relativistic effects to the isotope shift [1,2,3,4,5].…”