$\Delta (1232)$ Isobar Excitations in Nuclear Many-Body Systems derived from various NN Interactions

Abstract

$\Delta$ isobar components in the nuclear many-body wave function are investigated for the deuteron, light nuclei (${}^{16}O$) and infinite nuclear matter within the framework of the coupled-cluster theory. The predictions derived for various realistic models of the baryon-baryon interaction are compared to each other. These include local ($V28$) and non-local meson exchange potentials (Bonn${}_{2000}$) but also a model recently derived by the Salamanca group accounting for quark degrees of freedom. The characteristic differences which are obtained for the $N\Delta$ and $\Delta \Delta$ correlation functions are related to the approximation made in deriving the matrix elements for the baryon-baryon interaction.

Comments: 15 pages, 6 figures incl