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arXiv · 1808.00806

Relativistic corrections to the Bethe logarithm for the $2^3S$ and $2^3P$ states of He

Vladimir A. Yerokhin·Vojtěch Patkóš·Krzysztof Pachucki
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Abstract

With this work we start a project of calculating the QED contribution of order $\alpha^7m$ to the $2^3P$-$2^3S$ transition energy in helium, aiming for an accurate determination of the nuclear charge radius $r_E$ from measurements of the corresponding transition frequency. Together with the complementary determination of $r_E$ from muonic helium, this project will provide a stringent test of universality of electromagnetic interactions of leptons in the Standard Model. We report a calculation of the relativistic corrections to the Bethe logarithm for the $2^3S$ and $2^3P$ states, which is the most numerically demanding part of the project.

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Vladimir A. Yerokhin, Vojtěch Patkóš, Krzysztof Pachucki. 2018-08-02. Relativistic corrections to the Bethe logarithm for the $2^3S$ and $2^3P$ states of He. https://doi.org/10.1103/physreva.98.032503

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