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arXiv · hep-ph/0109128

Hyperfine structure in hydrogen and helium ion

Savely G. Karshenboim·Vladimir G. Ivanov
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Abstract

QED theory of the hyperfine splitting of the $1s$ and $2s$ state in hydrogen isotopes and helium-3 ion is considered. We develop an accurate theory of a specific difference 8E_{HFS}(2s)-E_{HFS}(1s). We take into account fourth order corrections and nuclear structure effects. The theoretical prediction is now of a higher accuracy than the experiment is. The study of the difference provides the most accurate test (on a level of a part in 10^8) of the QED theory of $1s$ HFS up to date. The theory agrees with most of the experimental data.

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Savely G. Karshenboim, Vladimir G. Ivanov. 2001-09-14. Hyperfine structure in hydrogen and helium ion. https://doi.org/10.1016/s0370-2693(01)01394-6

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