QED calculation of the $\bf{2p}$ fine structure in Li-like ions

TL;DR

This paper presents advanced quantum electrodynamics calculations for the fine-structure splitting in lithium-like ions, achieving higher accuracy than previous experimental data across a wide range of nuclear charges.

Contribution

It introduces a unified theoretical approach combining all-order nuclear strength and nonrelativistic QED methods for precise predictions of fine-structure intervals.

Findings

Predictions surpass experimental accuracy for Z=5 to 92.

Unified method improves theoretical precision.

Provides comprehensive data for Li-like ions.

Abstract

Large-scale {\em ab initio} QED calculations are performed for the $2p_{3/2}$--$2p_{1/2}$ fine-structure interval of Li-like ions with nuclear charges $Z = 5\,$--$\,92$. Improved theoretical predictions are obtained by combining together two complementary theoretical methods, namely, the approach that accounts for all orders in the binding nuclear strength and the nonrelativistic QED approach that accounts for all orders in the nonrelativistic electron-electron interaction. The resulting unified approach provides theoretical predictions which are more accurate than the available experimental results across the interval of the nuclear charges considered.