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arXiv · 1904.02015

Quantum electrodynamic corrections to the $1s3d$ states of the helium atom

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

We perform quantum electrodynamic calculations of the ionization energy of the $1s3d$ states of the $^4$He atom, including a complete evaluation of the $m\alpha^6$ correction. We find a large contribution from the nonradiative part of this correction, which has not been accounted for in previous investigations. The additional contribution shifts theoretical predictions for ionization energies by about 10$\,\sigma$. Despite this shift, we confirm the previously reported systematic deviations between measured experimental results and theoretical predictions for transitions involving $3D$ states. The reason for these deviations remains unknown.

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Albert Wienczek, Krzysztof Pachucki, Mariusz Puchalski, Vojtěch Patkóš, Vladimir A. Yerokhin. 2019-04-03. Quantum electrodynamic corrections to the $1s3d$ states of the helium atom. https://doi.org/10.1103/physreva.99.052505

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