Vacuum polarization corrections to hyperfine structure in many-electron atoms

TL;DR

This paper investigates vacuum polarization effects on hyperfine structure in many-electron atoms, emphasizing the importance of many-body effects for accurate corrections in precision atomic physics tests.

Contribution

It provides a detailed relativistic analysis of vacuum polarization corrections, including core relaxation and polarization effects, for alkali-metal and alkaline earth ions.

Findings

Vacuum polarization corrections are similar to hydrogenlike ions for s states.

Many-body effects significantly influence the correction's sign and magnitude.

Core polarization must be considered for accurate hyperfine structure calculations.

Abstract

We perform a theoretical study of vacuum polarization corrections to the hyperfine structure in many-electron atoms. Calculations are performed for systems of interest for precision atomic tests of fundamental physics belonging to the alkali-metal atoms and singly-ionized alkaline earths. The vacuum polarization is considered in the Uehling approximation, and we study the many-body effects core relaxation, core polarization, and valence-core correlations in the relativistic framework. We find that for s states, the relative vacuum polarization correction may be well-approximated by that for hydrogenlike ions, though for all other states account of many-body effects -- in particular, the polarization of the core -- is needed to obtain the correct sign and magnitude of the correction.