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arXiv · 2411.09912

The hyperfine anomaly in mercury and test of the Moskowitz-Lombardi rule

J. Vandeleur·G. Sanamyan·B. M. Roberts·J. S. M. Ginges
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Abstract

The Moskowitz-Lombardi rule gives a simple relation between the magnetic moment of an atomic nucleus and the effect of its radial distribution on the hyperfine structure - the magnetic hyperfine anomaly or "Bohr-Weisskopf" effect. It was originally formulated for mercury, for which experimental data for nuclear magnetic moments and hyperfine constants were available for a number of isotopes. While the relation for the differential effect between isotopes may be completely determined experimentally, the value for the additive constant that is needed to give the Bohr-Weisskopf (BW) effect for a single isotope has remained untested. In this work, we determine the BW effect in singly-ionized and neutral mercury from experimental muonic Hg-199 data together with our atomic calculations. We check this result by directly extracting the BW effect from the hyperfine constant for singly-ionized Hg-199 using state-of-the-art atomic many-body calculations. From this we deduce an empirical value for the additive constant in the Moskowitz-Lombardi rule, which differs significantly from the values advocated previously.

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J. Vandeleur, G. Sanamyan, B. M. Roberts, J. S. M. Ginges. 2024-11-15. The hyperfine anomaly in mercury and test of the Moskowitz-Lombardi rule. https://doi.org/10.1103/physreva.111.l050801

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