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Improved theoretical prediction for the 2s hyperfine interval in helium ion

Savely G. Karshenboim·Vladimir G. Ivanov
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Abstract

We consider the uncertainty of theoretical calculations for a specific difference of the hyperfine intervals in the 1s and 2s states in a light hydrogen-like atom. For a number of crucial radiative corrections the result for hydrogen atom and helium ion appears as an extrapolation of the numerical data from medium to low Z. An approach to a plausible estimation of the uncertainty is suggested using the example of the difference $D_{21}= 8E_{hfs}(2s)-E_{hfs}(1s)$.

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Savely G. Karshenboim, Vladimir G. Ivanov. 2005-07-28. Improved theoretical prediction for the 2s hyperfine interval in helium ion. https://doi.org/10.1139/p05-059

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