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arXiv · 2006.05115

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

Vladimir A. Yerokhin·Vojtěch Patkóš·Mariusz Puchalski·Krzysztof Pachucki
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Abstract

Quantum electrodynamical (QED) calculations of ionization energies of the $1snd\,D$ 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.

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Vladimir A. Yerokhin, Vojtěch Patkóš, Mariusz Puchalski, Krzysztof Pachucki. 2020-06-09. QED calculation of ionization energies of $1snd$ states in helium. https://doi.org/10.1103/physreva.102.012807

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