Local variations of charge radii for nuclei with even $Z$ from 84 to 120

TL;DR

This study systematically investigates the variations in nuclear charge radii for even Z nuclei from 84 to 120 using a new covariant density functional approach, revealing shell effects, shape deformations, and characteristic patterns across neutron numbers.

Contribution

It introduces a novel ansatz within covariant density functional theory to analyze charge radii in superheavy nuclei, highlighting shell closures and deformation effects.

Findings

Shell closures at N=126 and 184 significantly affect charge radii.

Arch-like charge radius patterns observed between shell closures.

Notable increase in charge radii across N=184 and from N=138 to 144 due to deformation.

Abstract

Pronounced changes of nuclear charge radii provide a stringent benchmark on the theoretical models and play a vital role in recognizing various nuclear phenomena. In this work, the systematic evolutions of nuclear charge radii along even $Z$=84-120 isotopic chains are firstly investigated by the recently developed new ansatz under the covariant density functional. The calculated results show that the shell closure effects of nuclear charge radii are remarkably shown at the neutron numbers $N=126$ and 184. Interestingly, the arch-like shapes of charge radii between these two strong neutron closed shells are naturally observed. Across the $N=184$ shell closure, the abrupt increase in charge radii is still evidently emerged. In addition, the rapid raise of nuclear charge radii from the neutron numbers $N=138$ to $N=144$ is also disclosed clearly in superheavy regions due to the enhanced shape deformation.