The Neutron Skin of ⁴⁸Ca and ²⁰⁸Pb: A Critical Analysis

We discuss the neutron skins of Ca-48 and Pb-208. We review and critically examine modern predictions and empirical constraints, with special attention to the different interpretations of the findings from the PREX-II experiment and the recently reported value of the neutron skin in Ca-48 extracted from the CREX experiment. We argue that, in the spirit of the ab initio philosophy, the path to understanding the behavior of dense neutron-rich matter must not circumvent fundamental nuclear forces. Based only on that argument, a thick neutron skin in (208)Pbis highly unlikely.