QED calculations of the E1 transition amplitude in neon-like iron and nickel

TL;DR

This paper presents ab initio QED calculations of E1 transition amplitudes in neon-like iron and nickel, highlighting the roles of electronic correlations and effective QED corrections.

Contribution

The study introduces a comprehensive method combining relativistic configuration interaction with effective QED operators to accurately compute transition amplitudes.

Findings

Many-electron mixing dominates in $2p o 3d$ transitions.

Correlation and one-electron effects partially cancel in $2p o 3s$ transitions.

Vertex QED corrections are negligible for these transitions.

Abstract

We calculated QED corrections to the $E1$ transition amplitudes in Ne-like iron and nickel. For the $2p \to 3d$ transitions the dominant effect came from the many-electron mixing, or electronic correlations. For the $2p \to 3s$ transitions the correlation and one-electron effects were comparable and tended to compensate each other. Our ab initio calculations showed that vertex corrections were negligible for both types of transitions. Other QED corrections were accurately reproduced by including effective QEDMOD operator in the many-electron relativistic configuration interaction calculation.