Precision calculation of hyperfine structure and the Zemach radii of ${}^{6,7}$Li${}^{+}$ ions

Abstract

The hyperfine structures of the $2{}^3{S}_1$ states of the ${}^6$Li${}^{+}$ and ${}^7$Li${}^{+}$ ions are investigated theoretically to extract the Zemach radii of the ${}^6$Li and ${}^7$Li nuclei by comparing with precision measurements. The obtained Zemach radii are larger than the previous values of Puchalski and Pachucki [\href{https://link.aps.org/doi/10.1103/PhysRevLett.111.243001}{Phys. Rev. Lett. {\bf 111}, 243001 (2013)}] and disagree with them by about 1.5 and 2.2 standard deviations for ${}^6$Li and ${}^7$Li, respectively. Furthermore, our Zemach radius of ${}^6$Li differs significantly from the nuclear physics value, derived from the nuclear charge and magnetic radii [\href{https://link.aps.org/doi/10.1103/PhysRevA.78.012513}{Phys. Rev. A {\bf 78}, 012513 (2008)}], by more than 6 sigma, indicating an anomalous nuclear structure for ${}^6$Li. The conclusion that the Zemach radius of ${}^7$Li is about 40\% larger than that of ${}^6$Li is confirmed. The obtained Zemach radii are used to calculate the hyperfine splittings of the $2{}^3{P}_J$ states of ${}^{6,7}$Li${}^{+}$, where an order of magnitude improvement over the previous theory has been achieved for ${}^7$Li${}^{+}$.

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• Improved theory of helium fine structure
• Hyperfine structure of Li and Be^+
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• Quantum electrodynamic calculation of the hyperfine structure of 3He
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• Quantum electrodynamic corrections to the $1s3d$ states of the helium atom
• Direct Measurement of the Forbidden $2^3{S}_1\to 3^3{S}_1$ Atomic Transition in Helium

Cited by in corpus (3)

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• Revised ${}^3$He nuclear charge radius due to electronic hyperfine mixing
• Splitting Isotope Shift in the $1s2p{}^3{P}_{0,1,2}$ Fine-Structure Triplet in ${}^{12,13,14}$C${}^{4+}$: Experiment and Theory