Neutrino Masses with Inverse Hierarchy from Broken Le-Lmu-Ltau: a Reappraisal
نویسندگان
چکیده
We discuss a class of models of neutrino masses and mixings with inverse hierarchy based on a broken U(1)F flavour symmetry with charge Le−Lμ−Lτ . The symmetry breaking sector receives separate contributions from flavon vev breaking terms and from soft mass breaking in the right handed Majorana sector. The model is able to reproduce in a natural way all observed features of the charged lepton mass spectrum and of neutrino masses and mixings (even with arbitrarily small θ13), with the exception of a moderate fine tuning which is needed to accomodate the observed small value of r = ∆m2sol/∆m 2 atm. e-mail address: [email protected] e-mail address: [email protected] currently at Scuola Normale Superiore Piazza dei Cavalieri 7 I-56100 Pisa, Italy
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