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$Δ(1232)$ Isobar Excitations and the Ground State of Nuclei

T. Frick·S. Kaiser·H. Müther·A. Polls·D. R. Entem·R. Machleidt
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Abstract

The influence of $Δ$ isobar components on the ground state properties of nuclear systems is investigated for nuclear matter as well as finite nuclei. Many-body wave functions, including isobar configurations, and binding energies are evaluated employing the framework of the coupled-cluster theory. It is demonstrated that the effect of isobar configurations depends in a rather sensitive way on the model used for the baryon-baryon interaction. As examples for realistic baryon-baryon interactions with explicit inclusion of isobar channels we use the local ($V28$) and non-local meson exchange potentials (Bonn$_{2000}$) but also a model recently developed by the Salamanca group, which is based on a quark picture. The differences obtained for the nuclear observables are related to the treatment of the interaction, the $π$-exchange contributions in particular, at high momentum transfers.

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T. Frick, S. Kaiser, H. Müther, A. Polls, D. R. Entem, R. Machleidt. 2001-09-18. $Δ(1232)$ Isobar Excitations and the Ground State of Nuclei. https://doi.org/10.1103/physrevc.65.034316

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