Model-QED operator for superheavy elements

TL;DR

This paper extends the model-QED-operator method to superheavy elements with nuclear charges 110 to 170, enabling efficient QED corrections in atomic calculations for these elements.

Contribution

The paper introduces an extended model-QED-operator applicable to superheavy elements, incorporating vacuum polarization and self-energy effects for high nuclear charges.

Findings

The model-QED-operator accurately reproduces ab initio QED results.

It can be integrated into existing atomic structure calculations.

Performance validated for elements with Z up to 170.

Abstract

The model-QED-operator approach [Phys. Rev. A 88, 012513 (2013)] to calculations of the radiative corrections to binding and transition energies in atomic systems is extended to the range of nuclear charges $110 \leqslant Z \leqslant 170$. The self-energy part of the model operator is represented by a nonlocal potential based on diagonal and off-diagonal matrix elements of the ab initio self-energy operator with the Dirac-Coulomb wave functions. The vacuum-polarization part consists of the Uehling contribution which is readily computed for an arbitrary nuclear-charge distribution and the Wichmann-Kroll contribution represented in terms of matrix elements similarly to the self-energy part. Performance of the method is studied by comparing the model-QED-operator predictions with the results of ab initio calculations. The model-QED operator can be conveniently incorporated in any numerical approach based on the Dirac-Coulomb-Breit Hamiltonian to account for the QED effects in a wide variety of superheavy elements.