Proton and neutron skins of light nuclei within the relativistic mean field theory

doi:10.1016/j.nuclphysa.2003.10.014

Nuclear Physics A

Volume 730, Issues 1–2, 12 January 2004, Pages 80-94

https://doi.org/10.1016/j.nuclphysa.2003.10.014 Get rights and content

Abstract

The relativistic mean field (RMF) theory is applied to the analysis of ground-state properties of Ne, Na, Cl and Ar isotopes. In particular, we study the recently established proton skin in Ar isotopes and neutron skin in Na isotopes as a function of the difference between the proton and the neutron separation energy. We use the TMA effective interaction in the RMF Lagrangian, and describe pairing correlation by the density-independent delta-function interaction. We calculate single neutron and proton separation energies, quadrupole deformations, nuclear matter radii and differences between proton radii and neutron radii, and compare these results with the recent experimental data.

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Citation Excerpt :
Effective interactions are employed with the inclusion of separable pairing interaction [17,18,35]. RHB theory has been tested several times and its successes involes the appreciable description of nuclei near the drip lines (exotic nuclides) [55–58,60]. It has also been used to study the deformed exotic nuclides as reported in references [61–64].
Shell structure evolution in isotopes (even Z and even N) of Silicon (Si), Sulphur (S), Argon (Ar) and Calcium (Ca) has been analysed. We have used both Relativistic Hartree-Bogoliubov theory and Non-Relativistic Hartree-Fock-Bogoliubov theory for the theoretical calculations of the physical observables of interest. We have employed the model based on Relativistic Hartree-Bogoliubov theory with the density dependent effective interactions of meson exchange and point coupling types. Calculations based on Hartree-Fock-Bogoliubov theory are carried out with different skyrme forces and their sensitivity has been tested. Physical observables of interest include binding energies, single neutron separation energies, two-neutron separation energies, shell closure parameter $D_{n}$ (Z, N) and differential variation $d S_{2 n}$ (Z, N) based on two neutron separation energy. Our theoretical results gives indication of shell closure at neutron number N =14 and neutron number N = 20 for the nuclei of Silicon (Si). Shell closures at neutron numbers N = 14, 20 and neutron number N = 28 are observed for Sulphur (S) nuclides. Argon (Ar) and Calcium (Ca) isotopes also provides the signature of shell closures at neutron numbers N = 20 and neutron number N = 28.

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Proton and neutron skins of light nuclei within the relativistic mean field theory

Abstract

Ann. Phys. (N.Y.)

Prog. Part. Nucl. Phys.

Nucl. Phys. A

Nucl. Phys. A

Nucl. Phys. A

Nucl. Phys. A

Nucl. Phys. A

Prog. Part. Nucl. Phys.

Ann. Phys. (N.Y.)

Nucl. Phys. A

Phys. Lett. B

Nucl. Phys. A

Nucl. Phys. A

Phys. Lett. B

Phys. Rev. Lett.

At. Data Nucl. Data Tables

Phys. Rev. Lett.