eV scale sterile neutrino and dark matter phenomenology in A < inf > 4 < /inf > ×U(1) < inf > B−L < /inf > Model

Abstract

We discuss an A4 flavor extended B-L model to realize an eV scale sterile neutrino, which is evident from both particle physics and cosmology experiments. The current framework includes a gauged B-L extension of standard model, where three exotic fermions with B-L charges -4,4, and 5 are introduced to cancel gauge anomalies. Absence of usual Dirac Yukawa couplings between the SM neutrinos and the exotic fermions allows natural realization of eV scale sterile-like neutrino and its mixing by invoking the A4 flavor symmetry. We demonstrate the neutrino phenomenology by perturbing the TBM mixing to obtain a large (formula presented). We also explored the extra contribution to the effective neutrino mass in neutrinoless double beta decay in the presence of eV scale sterile neutrino. On the other hand the interesting feature of the model is that two of three exotic fermions are stable dark matter candidates. We constrain the gauge parameters associated with U(1) gauge extension, using relic density and collider bounds.