Many-body calculations of relativistic energy shifts for single- and double-valence atoms

TL;DR

This paper employs advanced many-body computational methods to accurately calculate relativistic energy shifts in various ions, aiding the search for variations in the fine structure constant through quasar spectra.

Contribution

It introduces a comprehensive computational approach combining Hartree-Fock, perturbation theory, and configuration interaction for precise energy shift calculations.

Findings

Results agree well with previous calculations.

Breit contributions are analyzed.

Provides data useful for fundamental constant variation studies.

Abstract

Relativistic Hartree-Fock method together with many-body perturbation theory and configuration interaction techniques are used to calculate relativistic energy shifts for frequencies of the strong electric dipole transitions of C III, C IV, Na I, Mg I, Mg II, Al II, Al III, Si IV, Ca II and Zn II. These transitions are used for search of the variation of the fine structure constant in quasar absorption spectra. The results are in good agreement with previous calculations. The analysis of Breit contributions is also presented.