Neutrino democracy and other phenomenology from 5D SO(10) Original Research Article

We present a five-dimensional supersymmetric SO(10) model compactified on an orbifold S(1)/Z2×Z2′. The gauge symmetry G422≡SU(4)c×SU(2)L×SU(2)R, realized on one of the fixed points (branes), is spontaneously broken to the MSSM via the Higgs mechanism. Employing a flavor U(1) symmetry and suitably extending the ‘matter’ sector enables us to understand large mixings in the neutrino sector via a democratic approach, vs. the small CKM mixings. A residual R-symmetry on G422 brane helps eliminate the troublesome dimension five nucleon decay, while the U(1) symmetry plays an essential role in suppressing dimension six decay. For rare leptonic decays we expect BR(μ→eγ)∼BR(τ→μγ)∼BR(τ→eγ).