Zeeman splitting and g-factor in helium-like ions

Introduction. Research on the g-factor of highly charged ions has attracted considerable attention in recent years. For instance, high-precision measurements of the g-factor have enabled the most accurate determination of the electron mass and provided rigor verification of relativistic effects in the presence of a magnetic field.

Helium-like ions represent the simplest multi-electron systems, making them convenient objects for studying relativistic effects while accounting for interelectronic interactions. Calculations of correlation corrections to the energy for various electronic configurations of helium-like ions were presented in works of A. N. Artemyev, A. V. Malyshev and Y. S. Kozhedub. In the present work, we focus on the correlation corrections to the g-factor values.

Methods. The calculations were carried out using perturbation methods. The Breit approximation was employed to account for correlation effects. Quasi-degenerate perturbation theory was applied to correctly evaluate the g-factor and its corrections for the 1s2p states.

Results. In the present work, interelectronic-interaction corrections to the g-factor of the excited states for a wide range of nuclei charges (Z = 2 - 100) of helium-like ions are considered.

Conclusion. The obtained results will provide additional opportunities for testing quantum electrodynamics methods and determining fundamental constants and nuclear parameters such as the magnetic moment and charge distribution.