Hyperfine intervals in light hydrogenic atoms and ions are among the most accurately measured quantities in physics. The theory of QED corrections has recently advanced to the point that uncalculated terms for hydrogenic atoms and ions are probably smaller than 0.1 parts per million (ppm), and the experiments are even more accurate. The difference of the experiments and QED theory is interprete...

– We present a new theoretical analysis of the strongly suppressed F-and M-dependent Stark shifts of the Cs ground state hyperfine structure. Our treatment uses third order perturbation theory including off-diagonal hyperfine interactions not considered in earlier treatments. A numerical evaluation of the perturbation sum using bound states up to n=200 yields ground state tensor polarizabilitie...

"Measurement of transverse hyperfine interaction by forbidden transitions. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters.

The Fe Mössbauer spectroscopy on -iron II phthalocyanine FePc as a function of temperature 1.3 T 295 K and applied field 0 B 10 T has been used to study the peculiar magnetic properties of this ferromagnetic quasilinear chain type compound. One sextet with an internal hyperfine field Bint=66.2 T was observed at 1.3 K, a very large value for a bivalent iron with S=1 pointing to the existence of ...

The hyperfine-induced 2s2p P0−2s 2 S0 transition rate for Be-like 47Ti18+ was recently measured in a storage-ring experiment by Schippers et al. [Phys. Rev. Lett. 98, 033001 (2007)]. The measured value of 0.56(3) s−1 is almost 60% larger than the theoretical value of 0.356 s−1 from a multiconfiguration Dirac-Fock calculation by Marques et al. [Phys. Rev. A 47, 929 (1993)]. In this work, we use ...