A systematic study of the factors affecting central depletion in nuclei

Abstract

A systematic study of the central depletion of proton density has been performed in the isotonic chains of nuclei with neutron numbers N = 20 and 28 using different variants of the relativistic mean-field models. These models include either the non-linear contributions from the mesons with the coupling constants being density independent or the non-linearity of the mesonic fields realized through the density-dependent coupling strengths. The central depletion in deformed nuclei tends to disappear irrespective of the occupancy of the state in contrast to the spherical nuclei in which the unoccupancy of the state leads to the central depletion. Due to the differences in the strength of spin–orbit potentials in these models, the central depletions are found to be model dependent. The influence of the central depletion on the neutron-skin thickness is also investigated. It appears that the effects of the central depletion do not percolate far enough to display its finger prints on the trends of the neutron-skin thickness.