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arXiv · 2112.03514

Density dependence of the nuclear symmetry energy and neutron skin thickness in the KIDS framework

Panagiota Papakonstantinou
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Abstract

The KIDS framework for the nuclear equation of state (EoS) and energy density functional (EDF) offers the possibility to explore systematically the effect of EoS parameters on predictions for a variety of observables. The EoS parameters can be varied independently of each other and independently of assumptions regarding the in-medium nucleon effective mass. Here I present a pilot study of the neutron skin thickness (NST) in nuclei of current interest. The results indicate that variations of the symmetry energy slope parameter L by roughly 10 MeV and variations of the droplet-model counterpart of the curvature parameter $K_\tau$ by roughly 20 MeV affect predictions by comparable amounts. However, structural details may also have sizable effects on predictions, notably in the cases of $^{68}$Ni and $^{208}$Pb. This work is part of a systematic investigation of the NST within the KIDS framework and of a broader effort to constrain the density dependence of the nuclear symmetry energy.

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Panagiota Papakonstantinou. 2021-12-07. Density dependence of the nuclear symmetry energy and neutron skin thickness in the KIDS framework. https://arxiv.org/abs/2112.03514

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