Superheavy magic structures in the relativistic Hartree-Fock-Bogoliubov approach

TL;DR

This paper investigates superheavy nuclei using relativistic Hartree-Fock-Bogoliubov theory, predicting new magic numbers and identifying key shell effects influencing nuclear stability beyond lead-208.

Contribution

It introduces a comprehensive analysis of shell closures in superheavy nuclei within the RHFB framework, highlighting specific magic numbers and the sensitivity of shell effects to mean-field terms.

Findings

Predicted magic numbers: Z=120,138; N=172,184,228,258.

Favored doubly magic nucleus: 304120.

Shell effects depend on spin-orbit coupling and effective masses.

Abstract

We have explored the occurrence of the spherical shell closures for superheavy nuclei in the framework of the relativistic Hartree-Fock-Bogoliubov (RHFB) theory. Shell effects are characterized in terms of two-nucleon gaps $\delta_{2n(p)}$. Although the results depend slightly on the effective Lagrangians used, the general set of magic numbers beyond $^{208}$Pb are predicted to be $Z = 120$, $138$ for protons and $N = 172$, 184, 228 and 258 for neutrons, respectively. Specifically the RHFB calculations favor the nuclide $^{304}$120 as the next spherical doubly magic one beyond $^{208}$Pb. Shell effects are sensitive to various terms of the mean-field, such as the spin-orbit coupling, the scalar and effective masses.