ElectrongFactor in Hydrogenic Atoms

Abstract

The electron $g$ factor is calculated to a high degree of accuracy for the ground state of hydrogenic atoms. In addition to binding corrections of order ${\left(Z\alpha \right)}^2$, ${\left(Z\alpha \right)}^2\frac{m}{M}$, and ${\left(Z\alpha \right)}^2{\left(\frac{m}{M}\right)}^2$, radiative level shifts of order $\alpha {\left(Z\alpha \right)}^2$ and $\alpha {\left(Z\alpha \right)}^2\frac{m}{M}$ are obtained. These level shifts differ from those previously given in the literature. The origin of the discrepancies is discussed in some detail.