Consistent description of 12C and 16O using finite range three-body interaction

TL;DR

This paper demonstrates a method to consistently describe 12C and 16O nuclei using a finite-range three-body interaction, incorporating shell model coupling and modified phenomenological interactions to improve binding energy predictions.

Contribution

It introduces a modified Tohsaki interaction with additional exchange terms and coupling to shell model components, enabling accurate description of 12C, 16O, and neutron-rich nuclei like 6He.

Findings

Improved binding energy predictions for 12C and 16O.

Successful application to neutron-rich 6He nucleus.

Enhanced interaction model with exchange terms.

Abstract

Consistent description of 12C and 16O has been a long standing problem of microscopic alpha cluster models, where the wave function is fully antisymmetrized and the effective interaction is applied not between alpha clusters but between nucleons. When the effective interaction is designed to reproduce the binding energy of 16O (four alpha), the binding energy of 12C (three alpha) becomes underbound by about 10 MeV. In the present study, by taking into account the coupling with the jj-coupling shell model components and utilizing Tohsaki interaction, which is phenomenological but has finite-range three-body interaction terms, we show that consistent understanding of these nuclei can be achieved. The original Tohsaki interaction gives small overbound of about 3 MeV for 16O, and this is improved by slightly modifying three-body Majorana exchange parameter. Also, the coupling with the jj-coupling shell model wave function strongly contributes to the increase of the binding energy of 12C. So far the application of Tohsaki interaction has been limited to 4N nuclei, and here, we add Bartlet and Heisenberg exchange terms in the two-body interaction for the purpose of applying it to neutron-rich systems, and it is applied to 6He.