High-precision measurements of the ground-state hyperfine structure of heavy highly charged ions [1-4] and the g factor of H-like carbon [5] and oxygen [6] have triggered a great interest to related theoretical calculations. In particular, the 2002 CODATA value for the electron mass is derived mainly from the experimental and theoretical g factor values for H-like carbon and oxygen and it is 4 ...

While measurements of the hyperfine structure of hydrogen-like atoms are traditionally regarded as test of bound-state QED, we assume that theoretical QED predictions are accurate and discuss the information about the electromagnetic structure of protons that could be extracted from the experimental values of the ground state hyperfine splitting in hydrogen and muonic hydrogen. Using recent the...

We demonstrate that the generalized Gell-Mann–Low theorem permits for a systematic expansion around the nonrelativistic limit when applied to bound states in the Wick-Cutkosky model, Yukawa theory, and QED (in Coulomb gauge). We apply this expansion to obtain new results for the fine and hyperfine structure of bound states in the cases of the Wick-Cutkosky model and Yukawa theory, and reproduce...

We have measured the hyperfine structure of mutually perturbing rovibrational levels of the 1sbd P0 and 2sAd S states of the NaK molecule, using the perturbation-facilitated optical-optical double resonance method with copropagating lasers. The unperturbed 1sbd P0 levels are split into four hyperfine components by the Fermi contact interaction bFI ·S. Mixing between the 1sbd P0 and 2sAd S level...

Radiative Corrections to the Muonium Hyperfine Structure.