Dirac neutrinos and gauged lepton number

Abstract

We propose the first scotogenic neutrino mass model with gauged lepton number $U(1{)}_L$, which is spontaneously broken by three units $\hat{I}”L=3$ down to a residual discrete gauge symmetry ${\mathbb{Z}}_6$. The latter guarantees that neutrinos acquire tiny Dirac masses via a one-loop scotogenic mechanism, simultaneously stabilizing the lightest electrically neutral particle with non-trivial charge under the preserved ${\mathbb{Z}}_6$ symmetry. In our model there is a scalar particle identified as weakly interacting massive particle dark matter (DM) candidate. We analyzed its compatibility with the existing data on direct DM detection experiments and the DM relic abundance. We also address charged lepton flavor violating decays in our model and find that their predicted rates are within the reach of current experimental sensitivity.

14 pages, 4 figures