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arXiv · 1902.07592

A systematic study of the factors affecting central depletion in nuclei

G. Saxena·M. Kumawat·B. K. Agrawal·Mamta Aggarwal
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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 (RMF) 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 $2s_{1/2}$ state in contrast to the spherical nuclei in which the unoccupancy of $2s_{1/2}$ 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.

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G. Saxena, M. Kumawat, B. K. Agrawal, Mamta Aggarwal. 2019-02-20. A systematic study of the factors affecting central depletion in nuclei. https://doi.org/10.1088/1361-6471%2Fab0853

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