Microscopic Description of Isospin Mixing Pairing Correlations in the Framework of an Algebraic Sp(4) Model

We explore isospin mixing beyond that due to the Coulomb interaction in the framework of an exactly solvable microscopic sp(4) algebraic approach. Specifically, we focus on the isospin non-conserving part of the pure nuclear pairing interaction. The outcome of this study shows the significance of the pairing charge dependence and its role in mixing isospin multiplets of pairing-governed isobaric analog 0 states in light and medium mass nuclei, especially in nuclei with equal numbers of protons and neutrons. The model reveals possible, but still extremely weak, non-analog β-decay transitions and estimates their relative strengths within a shell closure.