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arXiv · 2312.15434

New quantification of symmetry energy from neutron skin thicknesses of $^{48}$Ca and $^{208}$Pb

Rong An·Shuai Sun·Li-Gang Cao·Feng-Shou Zhang
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Abstract

Precise knowledge of the nuclear symmetry energy can be tentatively calibrated through multimessenger constraints. The neutron skin thickness of a heavy nucleus is one of the most sensitive indicators for probing the isovector components of effective interactions in asymmetric nuclear matter. Recent studies have suggested that the experimental data from the CREX and PREX2 Collaborations are not mutually compatible within existing nuclear models. In this study, we review the quantification of the slope parameter of symmetry energy $L$ from the neutron skin thicknesses of $^{48}$Ca and $^{208}$Pb. Skyrme energy density functionals classified by various isoscalar incompressibility coefficients $K$ are employed to evaluate the bulk properties of finite nuclei. The calculated results suggest that the slope parameter $L$ deduced from $^{208}$Pb is sensitive to the compression modulus of symmetric nuclear matter, but not that from $^{48}$Ca. The effective parameter sets classified by $K=220$ MeV can provide an almost overlaping range of $L$ from $^{48}$Ca and $^{208}$Pb.

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Rong An, Shuai Sun, Li-Gang Cao, Feng-Shou Zhang. 2023-12-24. New quantification of symmetry energy from neutron skin thicknesses of $^{48}$Ca and $^{208}$Pb. https://doi.org/10.1007/s41365-024-01551-w

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