Proposal of highly accurate tests of Breit and QED effects in the ground state 2p5 of the F-like isoelectronic sequence

Abstract

We propose that the ground term transition, 2p5P3/22-P1/22, for ions in the F-like isoelectronic sequence could be used to accurately test current methods to compute Breit and quantum-electrodynamic (QED) effects. These systems are of interest since correlation is small due to what we will label Layzer quenching. Using the multiconfiguration Dirac-Hartee-Fock method, we investigate how correlation, Breit and QED corrections vary along the sequence and show that QED dominates over correlation already for Z≈20. We also investigate the behavior of different QED effects as a function of the nuclear charge and find that the self-energy dominates for the mid-Z range (40-80), but then decreases to change sign for Z≈90. For a few elements between Z=85 and 90 the vacuum polarization is the leading term, while for higher Z the two QED contributions cancel. This opens up the possibility for these ions to carefully test the frequency-dependent transverse photon correction. The uncertainties of the treatment of the well-understood frequency-independent Breit correction and correlation are expected to be at least three orders of magnitude smaller than the QED and frequency-dependent transverse photon corrections for high Z. In this work we also compare and evaluate the results from three different methods to compute self-energies. (Less)