Tensor force and deformation in even-even nuclei

TL;DR

This paper develops a nuclear structure model incorporating tensor forces and deformation effects, using a variational approach with Hartree-Fock and BCS equations, applied to isotopes with 34 protons or neutrons, and compares results with experimental data.

Contribution

It introduces a model that combines tensor interactions and deformation in open shell nuclei using a variational method with self-consistent Hartree-Fock and BCS calculations.

Findings

Tensor force influences nuclear deformation and energies.

Model accurately reproduces experimental data for selected isotopes.

Deformation effects are significant in open shell nuclei.

Abstract

The variational principle is used to build a model which describes open shell nuclei with ground state deformations. Hartree-Fock equations are solved by using single particle wave functions whose radial parts depend on the projection of the angular momentum on the quantization axis. Pairing effects are taken into account by solving Bardeen-Cooper-Schrieffer equations in each step of the minimisation procedure. The Gogny D1S finite-range interaction and an extension of it that includes tensor terms are consistently used in both parts of our calculations. The model is applied to study a set of isotopes with 34 protons and of isotones with 34 neutrons. Total energies, density distributions, their radii and single particle energies are analysed and the results of our calculations are compared with the available experimental data. We focused our attention on the effects of the deformation and of the tensor force on these observables. Our model describes open shell nuclei from a peculiar perspective and opens the possibility of future theoretical developments.