Absolute neutrino mass scale and dark matter stability from flavour symmetry

Abstract

Abstract We explore a simple but extremely predictive extension of the scotogenic model. We promote the scotogenic symmetry ℤ2 to the flavour non-Abelian symmetry Σ(81), which can also automatically protect dark matter stability. In addition, Σ(81) leads to striking predictions in the lepton sector: only Inverted Ordering is realised, the absolute neutrino mass scale is predicted to be mlightest≈ 7.5×10−4 eV and the Majorana phases are correlated in such a way that |mee| ≈ 0.018 eV. The model also leads to a strong correlation between the solar mixing angle θ12 and δCP, which may be falsified by the next generation of neutrino oscillation experiments. The setup is minimal in the sense that no additional symmetries or flavons are required.