Revisiting Neutrino Masses In Clockwork Models

In this paper, we have looked at various variants of the clockwork model and studied their impact on the neutrino masses. Some of the generalizations such as generalized CW and next-to-nearest neighbour interaction CW have already been explored by a few authors. In this study, we studied non-local CW for the fermionic case and found that non-local models relax the $\left| q \right| > 1$ constraint to produce localization of the zero mode. We also made a comparison among them and have shown that for some parameter ranges, non-local variants of CW are more efficient than ordinary CW in generating the hierarchy required for the $\nu$ mass scale. Finally, phenomenological constraints from $BR(\mu \rightarrow e \gamma )$ FCNC process and Higgs decay width have been imposed on the parameter space in non-local and both-sided clockwork models. We have listed benchmark points which are surviving current experimental bounds from MEG and are within the reach of the upcoming MEG-II experiment.