TUM-HEP-457/02 Bilarge leptonic mixing from Abelian horizontal symmetries (original) (raw)

We construct and present a model for leptonic mixing based on higher-dimensional operators, using the Froggatt{Nielsen mechanism, and Abelian horizontal symmetries (avor symmetries) of continuous and discrete type. Our model naturally yields bilarge leptonic mixing, coming from both the charged leptons and the neutrinos, and an inverted neutrino mass hierarchy spectrum. The obtained values of the parameters, i.e., the leptonic mixing parameters and the neutrino mass squared dierences, are all consistent with the atmospheric neutrino data and the Mikheyev{Smirnov{Wolfenstein large mixing angle solution for the solar neutrino problem.