RMF+BCS Description of Some Traditional Neutron Magic Isotones

G Saxena,M Kaushik,D Singh,S Lunardi,P Di Nezza,P.G Bizzeti,M Chiari,R Menegazzo,C Signorini,C Bucci,A Dainese,J.J Valiente-Dobon,A Nannini

doi:10.1051/epjconf/20146602095

Abstract

The traditional neutron magic nuclei with N = 8, 20, 28, 50, 82 and 126, and those with neutron sub-magic number N = 40 are investigated within the relativistic mean-field plus BCS (RMF +BCS) approach. The results indicate appearance of new proton magic numbers as well as the disappearance of conventional magic numbers for nuclei with extreme isospin values. The calculated energies and densities do not indicate any tendency for the proton halo formations in any of the proton rich isotones due to Coulomb interaction and di erent single particle spectra. However, the potential barrier provided by the Coulomb interaction and that due to the centrifugal force may cause a long delay in the actual decay of proton rich nucleus resulting the extended drip line.

Highlights

Experimental and theoretical studies of exotic nuclei with extreme isospin values are most active areas in the field of nuclear physics in a days [1]
0.047 MeV, whereas proton Fermi energy is seen to be f = -0.732 MeV. This state has an appreciable pairing gap akin to bound state and wave function confined in the potential region. This state is considered as a resonant state resulting the bound isotone 82
We found that near proton drip line contribution of resonant states plays a significant role in deciding the proton drip line for isotonic chains

Summary

Introduction

Experimental and theoretical studies of exotic nuclei with extreme isospin values are most active areas in the field of nuclear physics in a days [1]. The relativistic mean field (RMF) theory has been extensively used for the study of unstable nuclei [2,3,4]. We have applied the RMF model [5, 6] for a detailed calculations of the ground state properties of the neutron magic isotones with neutron number N = 8, 20, 28, 50, 82, 126 and the neutron sub-magic isotones with neutron number N = 40 using the TMA and the NL-SH force parameterizations. Our RMF calculations have been carried out using the model Lagrangian density with nonlinear terms both for the σ and ω mesons along with the TMA parametrization as described in detail in Refs. For further details of these formulations we refer the readers to ref. [5, 6, 9, 10]

Drip-Line Nuclei

Pairing Energy

Two Proton Separation Energy