QED calculation of ionization energies of $1snd$ states in helium

Abstract

Quantum electrodynamical (QED) calculations of ionization energies of the $1sndD$ states are performed for the helium atom. We reproduce the previously known relativistic and QED effects up to order $m{\alpha }^5$ and extend the theory by calculating the complete $m{\alpha }^6$ correction. The total contribution of the $m{\alpha }^6$ effects is shown to be much smaller than previously estimated, due to a large cancelation between the radiative and non-radiative parts of this correction. As a result of our calculations, we confirm the previously reported deviations between measured transition energies and theoretical predictions for the $nD$--$2S$ and $nD$--$2P$ transitions. Possible reasons for this discrepancy are analyzed.

References in corpus (6)

• ${\alpha }^4$ Ry corrections to singlet states of helium
• Complete ${\alpha }^{6}m$ corrections to the ground state of H${}_2$
• Helium energy levels including $m{\alpha }^6$ corrections
• High-precision spectroscopy of the forbidden 2 3S1 - 2 1P1 transition in quantum degenerate metastable helium
• Nonradiative ${\alpha }^{7}m$ QED effects in Lamb shift of helium triplet states
• Quantum electrodynamic corrections to the $1s3d$ states of the helium atom

Cited by in corpus (6)

• Complete ${\alpha }^{7}m$ Lamb shift of helium triplet states
• Atomic structure calculations of helium with correlated exponential functions
• Variational versus perturbative relativistic energies for small and light atomic and molecular systems
• QED corrections to the correlated relativistic energy: one-photon processes
• Thermal corrections for positronium
• Frequency measurements of transitions from the $2^3{P}_2$ state to the $5^1{D}_2$, $5^3{S}_1$, and $5^{3}D$ states in ultracold helium