Theoretical energies of low-lying states of light helium-like ions

TL;DR

This paper presents highly precise quantum electrodynamical calculations of energy levels for low-lying states of helium-like ions with nuclear charge Z=3 to 12, including relativistic and recoil effects up to high orders.

Contribution

It advances the theoretical understanding by calculating energy levels with higher-order corrections than previously achieved, improving accuracy for light helium-like ions.

Findings

Calculated energy levels for specific states of helium-like ions.

Included all relativistic, QED, and recoil effects up to specified orders.

Enhanced the precision of theoretical predictions for light helium-like ions.

Abstract

Rigorous quantum electrodynamical calculation is presented for energy levels of the 1^1S, 2^1S, 2^3S, 2^1P_1, and 2^3P_{0,1,2} states of helium-like ions with the nuclear charge Z=3...12. The calculational approach accounts for all relativistic, quantum electrodynamical, and recoil effects up to orders m\alpha^6 and m^2/M\alpha^5, thus advancing the previously reported theory of light helium-like ions by one order in \alpha.