Evolution of $N = 28$ shell closure in relativistic continuum Hartree-Bogoliubov theory

TL;DR

This paper investigates how the N=28 shell closure evolves in certain isotopes using relativistic continuum Hartree-Bogoliubov theory, revealing its quenching in sulfur but persistence in other isotopes.

Contribution

It provides a detailed analysis of the evolution of the N=28 shell gap across different isotopes within the RCHB framework, highlighting the impact of proton number on shell erosion.

Findings

N=28 shell gap quenched in sulfur isotopes

Shell gap persists in argon, calcium, and titanium isotopes

Shell erosion linked to potential evolution with proton number

Abstract

The $N = 28$ shell gap in sulfur, argon, calcium and titanium isotopes is investigated in the framework of relativistic continuum Hartree-Bogoliubov (RCHB) theory. The evolutions of neutron shell gap, separation energy, single particle energy and pairing energy are analyzed, and it is found that $N = 28$ shell gap is quenched in sulfur isotopes but persists in argon, calcium and titanium isotopes. The evolution of $N = 28$ shell gap in $N = 28$ isotonic chain is discussed, and the erosion of $N = 28$ shell gap is understood with the evolution of potential with proton number.