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## Full-Text Articles in Physics

A Rigorous Treatment Of O(Α 6mc 2) Qed Corrections To The Fine Structure Splittings Of Helium, T. Zhang, Gordon W. F. Drake

#### A Rigorous Treatment Of O(Α 6mc 2) Qed Corrections To The Fine Structure Splittings Of Helium, T. Zhang, Gordon W. F. Drake

*Physics Publications*

Relativistic formulae for the energy level shifts due to electron self-energy corrections are derived within the external potential Bethe-Salpeter formalism. A rigorous treatment of QED corrections to the fine structure splittings of helium is carried out. Although some individual self-energy diagrams give contributions of order α 6mc 2, they are shown to sum to zero. In addition, the α 6mc 2 correction from vertex modifications in the presence of Coulomb photons does not contribute. Therefore, a rigorous treatment of all QED corrections of order α 6mc 2 to the fine structure splittings of helium now appears to be complete. © 1994 ...

Lamb Shifts And Hyperfine Structure In Li+6 And Li+7: Theory And Experiment, E. Riis, A. G. Sinclair, O. Poulsen, Gordon W. F. Drake

#### Lamb Shifts And Hyperfine Structure In Li+6 And Li+7: Theory And Experiment, E. Riis, A. G. Sinclair, O. Poulsen, Gordon W. F. Drake

*Physics Publications*

High-precision laser-resonance measurements accurate to ±0.5 MHz or better are reported for transitions among the 1s2s 3S1-1s2p 3PJ hyperfine manifolds for each of J=0, 1, and 2 in both Li+6 and Li+7. A detailed analysis of hyperfine structure is performed for both the S and P states, using newly calculated values for the magnetic dipole and electric quadrupole coupling constants, and the hyperfine shifts subtracted from the measurements. The resulting transition frequencies are then analyzed on three different levels. First, the isotope shifts in the fine-structure splittings are calculated from the relativistic reduced mass and recoil ...

High-Precision Calculations Of The Zeeman Effect In The 2 3pj, 2 1p1, 2 3s1, And 3 3pj States Of Helium, Z. C. Yan, Gordon W. F. Drake

#### High-Precision Calculations Of The Zeeman Effect In The 2 3pj, 2 1p1, 2 3s1, And 3 3pj States Of Helium, Z. C. Yan, Gordon W. F. Drake

*Physics Publications*

The g factors for the Zeeman effect, including relativistic corrections up to order 2 a.u., are calculated to high precision for the 2 3PJ, 2 1P1, 2 3S1, and 3 3PJ states of helium, using variational wave functions constructed from doubled Hylleraas-type basis sets. Our results clarify the present disagreements among the existing theoretical values for the g factors. The experimental values of the fine-structure splittings for the helium 3 3PJ states, measured by Yang et al. [Phys. Rev. A 32, 2249 (1985); 33, 1725 (1986)], are reanalyzed, using our improved g factors. © 1994 The American Physical Society.