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Improved theory of helium fine structure

Krzysztof Pachucki
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Abstract

Improved theoretical predictions for the fine-structure splitting of $2^3P_J$ levels in helium are obtained by the calculation of contributions of order $α^5 Ry$. New results for transition frequencies, $ν_{01} = 29 616 943.01(17)$ kHz and $ν_{12} = 2 291 161.13(30)$ kHz disagree significantly with the experimental values, indicating an outstanding problem in bound state QED.

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Krzysztof Pachucki. 2006-07-01. Improved theory of helium fine structure. https://doi.org/10.1103/physrevlett.97.013002

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