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arXiv · 2508.10767

Ab initio computations of the fourth-order charge density moments of $^{48}$Ca and $^{208}$Pb

T. Miyagi·M. Heinz·A. Schwenk
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Abstract

Neutron skins of neutron-rich nuclei connect nuclei with the matter in neutron stars. High-precision measurements of nuclear charge densities to extract higher-order moments are proposed to be sensitive to neutron radii and skin thicknesses. We investigate the charge density of $^{48}$Ca and $^{208}$Pb, leading candidates for such studies, with ab initio nuclear structure calculations. We find strong correlations between the fourth-order charge density moment $R_\mathrm{ch}^4$ and the charge and neutron radii, allowing us to predict $R_\mathrm{ch}^4$ for $^{48}$Ca and $^{208}$Pb. We find a substantially weaker correlation between the fourth-order charge density moment and the neutron skin, limiting the ability of high-precision electron scattering to determine the neutron skin in a model-independent manner.

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T. Miyagi, M. Heinz, A. Schwenk. 2025-08-14. Ab initio computations of the fourth-order charge density moments of $^{48}$Ca and $^{208}$Pb. https://doi.org/10.1016/j.physletb.2025.140032

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