The inverse process of ${}^{9}\mathrm{Be}$ photo-disintegration, including both sequential and direct reactions combining two $\alpha$ and a neutron into $^9\textrm{Be}$, is a reaction of astrophysical interest, because it represents an alternative path to the ${}^{12}\mathrm{C}$ formation in a neutron-rich environment. Here we present the study of the inclusive reaction $\gamma +...
The necessity of calculating reliable nuclear matrix elements for neutrinoless double $\beta$ decay has further stimulated the research on the mechanisms responsible for the renormalization of the $\beta$-decay operator. We tackle this point using the many-body perturbation theory to derive effective Hamiltonian and operators for nuclear shell model calculations. Here, I will present recent...
