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arXiv · 1610.04060

Higher-order recoil corrections for triplet states of the helium atom

V. Patkos·V. A. Yerokhin·K. Pachucki
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Abstract

Nuclear recoil corrections of order $α^6\,m^2/M$ are calculated for the lowest-lying triplet states of the helium atom. It improves the theoretical prediction for the isotope shift of the $2^3S-2^3P$ transition energy and influences the determination of the ${}^3\textrm{He}-{}^4\textrm{He}$ nuclear charge radii difference. This calculation is a step forward on the way towards the direct determination of the charge radius of the helium nucleus from spectroscopic measurements.

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V. Patkos, V. A. Yerokhin, K. Pachucki. 2016-10-13. Higher-order recoil corrections for triplet states of the helium atom. https://doi.org/10.1103/physreva.94.052508

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