Relativistic Bethe logarithm for triplet states of helium-like ions

Abstract

We report a calculation of relativistic corrections of order $m{\alpha }^7$ to the Bethe logarithm for the $2^{3}S$ and $2^{3}P$ states of helium-like ions. The calculation is required for improving the accuracy of theoretical energies of helium-like ions and for checking the evaluation of the $m{\alpha }^7$ effects in helium performed in [V. Patkóš, V. A. Yerokhin, K. Pachucki, Phys. Rev. A 103, 042809 (2021)], where a significant discrepancy with experimental results was found. The large-$Z$ limit of the relativistic Bethe logarithm is determined numerically, in excellent agreement with the analytical results obtained from the hydrogen theory.

References in corpus (4)

• Nonrelativistic QED approach to the Lamb shift
• Improved theory of helium fine structure
• Complete ${\alpha }^{7}m$ Lamb shift of helium triplet states
• Atomic structure calculations of helium with correlated exponential functions

Cited by in corpus (3)

• Imaging-assisted single-photon Doppler-free laser spectroscopy and the ionization energy of metastable triplet helium
• Collinear Laser Spectroscopy of $2{}^3{S}_1\to 2{}^3{P}_J$ transitions in helium-like ${}^{12}{\mathrm{C}}^{4+}$
• QED $m{\alpha }^7$ effects for triplet states of helium-like ions