Addressing neutrino mixing models with DUNE and T2HK

Abstract

We consider schemes of neutrino mixing arising within the discrete symmetry approach to the well-known flavour problem. We concentrate on 3 ν mixing schemes in which the cosine of the Dirac CP violation phase δCP satisfies a sum rule by which it is expressed in terms of three neutrino mixing angles θ12, θ23, and θ13, and a fixed real angle θ12ν, whose value depends on the employed discrete symmetry and its breaking. We consider five underlying symmetry forms of the neutrino mixing matrix: bimaximal (BM), tri-bimaximal (TBM), golden ratio A (GRA) and B (GRB), and hexagonal (HG). For each symmetry form, the sum rule yields specific prediction for cos δCP for fixed θ12, θ23, and θ13. In the context of the proposed DUNE and T2HK facilities, we study (i) the compatibility of these predictions with present neutrino oscillation data, and (ii) the potential of these experiments to discriminate between various symmetry forms.