Sterile neutrino contribution to Neutrinoless double beta decay in seesaw models

Jacobo López Pavón

SISSA and INFN (Trieste)

We will review the general phenomenology of neutrinoless double beta decay in seesaw models. In particular, we focus on the dependence of the decay rate on the mass of the extra states introduced to generate the light neutrino masses. The neutrino mass generation mechanism induces correlations among the different contribution to the decay rate which should be considered. We will study whether the contribution from the extra states can dominate over the light neutrino one. This may occur if the ``heavy" spectrum is hierarchical with some of the extra states below ~100 MeV and others above this scale. In principle, a dominant heavy neutrino contribution is also possible at tree level for a different spectrum if the light neutrino contribution partially cancels out. In the second part of the talk we focus on this case paying special attention to the one-loop corrections to light neutrino masses, their contribution to the process and correlation with the heavy sector.