Many-electron QED corrections to the g factor of lithiumlike ions

TL;DR

This paper presents a precise quantum electrodynamics (QED) calculation of the g factor for lithiumlike ions, improving theoretical accuracy and confirming experimental results for silicon-28.

Contribution

It provides a rigorous two-photon exchange correction calculation and enhances the accuracy of g factor predictions for lithiumlike ions, especially at high atomic numbers.

Findings

Theoretical g factor for $^{28}$Si$^{11+}$ matches experimental data within uncertainties.

Improved calculations increase the accuracy of g factor predictions for lithiumlike ions.

Enhanced understanding of QED effects in multi-electron ions.

Abstract

A rigorous QED evaluation of the two-photon exchange corrections to the g factor of lithiumlike ions is presented. The screened self-energy corrections are calculated for the intermediate-$Z$ region and its accuracy for the high-$Z$ region is essentially improved in comparison with that of previous calculations. As a result, the theoretical accuracy of the g factor of lithiumlike ions is significantly increased. The theoretical prediction obtained for the g factor of $^{28}$Si$^{11+}$ ${\rm g}_{\rm th} = 2.000\,889\,892(8)$ is in an excellent agreement with the corresponding experimental value ${\rm g}_{\rm exp} = 2.000\,889\,889\,9(21)$ [A. Wagner et al., Phys. Rev. Lett. 110, 033003 (2013)].