Neutrinoless double beta decay studied with configuration mixing methods

We study neutrinoless double beta decay of several isotopes with state-of-the-art beyond self-consistent mean field methods to compute the nuclear matrix elements (NME). The generating coordinate method with particle number and angular momentum projection (GCM +PNAMP) is used for finding mother and granddaughter states and evaluating transition operators between different nuclei. We analyze explicitly the role of the deformation, pairing and configuration mixing in the evaluation of the NME.