Implication of shell quenching in scandium isotopes around N=20

Abstract

Shell closure structures are commonly observed phenomena associated with nuclear charge radii throughout the nuclide chart. Inspired by recent studies demonstrating that the abrupt change can be clearly observed in the charge radii of the scandium isotopic chain across the neutron number $N=20$, we further review the underlying mechanism of the enlarged charge radii for ${}^{42}$Sc based on the covariant density functional theory. The pairing correlations are tackled by solving the state-dependent Bardeen-Cooper-Schrieffer equations. Meanwhile, the neutron-proton correlation around the Fermi surface derived from the simultaneously unpaired proton and neutron is appropriately considered in describing the systematic evolution of nuclear charge radii. The calculated results suggest that the abrupt increase in charge radii across the $N=20$ shell closure seems to be improved along the scandium isotopic chain if the strong neutron-proton correlation is properly included.

10 pages, 4 figures

References in corpus (16)

• Relativistic Continuum Hartree Bogoliubov Theory for Ground State Properties of Exotic Nuclei
• Nuclear magic numbers: new features far from stability
• New parametrization for the nuclear covariant energy density functional with point-coupling interaction
• Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. XII: Stiffness and stability of neutron-star matter
• Nuclear charge radii: Density functional theory meets Bayesian neural networks
• Global study of beyond-mean-field correlation energies in covariant energy density functional theory using a collective Hamiltonian method
• Charge Radius of Neutron-deficient ${}^{54}$Ni and Symmetry Energy Constraints Using the Difference in Mirror Pair Charge Radii
• Neutron skin and signature of the $N$ = 14 shell gap found from measured proton radii of ${}^{17-22}$N
• Difference in proton radii of mirror nuclei as a possible surrogate for the neutron skin
• Proton distribution radii of ${}^{16-24}$O: signatures of new shell closures and neutron skin
• Cooper pairs in atomic nuclei
• Novel ansatz for charge radii in density functional theories
• Correlations between charge radii differences of mirror nuclei and stellar observables
• Angular momentum and parity projected multidimensionally constrained relativistic Hartree-Bogoliubov model
• Surprising charge-radius kink in the Sc isotopes at N=20
• Towards accurate nuclear mass tables in covariant density functional theory