Nuclear symmetry energy and the PREX-CREX neutron skin puzzle within the KIDS framework

TL;DR

This paper reviews the KIDS framework for nuclear equations of state, discusses recent symmetry energy results, and proposes models that reconcile PREX-II and CREX neutron skin measurements, suggesting a softening of the EoS at low densities.

Contribution

It introduces EDF models within the KIDS framework that can simultaneously fit PREX-II and CREX data, addressing the neutron skin puzzle.

Findings

EDF models can reproduce PREX-II and CREX within error bars

EoSs that soften at low densities, possibly due to clusterization

Further analysis of dipole polarizability needed

Abstract

I briefly review the KIDS theoretical framework for the nuclear equation of state (EoS) and energy density functional (EDF), I discuss recent results for the curvature parameter of the symmetry energy, and I address the PREX-CREX puzzle. I show that it is possible to obtain EDF models which can reproduce both PREX-II and CREX results each within its respective error bars. Such EDFs correspond to EoSs which soften towards low densities, as could be attributed to clusterization. Before such a scenario is considered viable, the dipole polarizability should also be examined.