Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9861391 | Physics Letters B | 2005 | 7 Pages |
Abstract
The leptonic mixing angle θ13 is known to be small. If it is indeed tiny, the simplest explanation is that charged leptons mix only in the μ-Ï sector and neutrinos only in the 1-2 sector. We show that this pattern may be explained by the discrete symmetry Z2ÃZ2 of a complete Lagrangian, which has 2 Higgs doublets and 2 Higgs triplets (or 2 heavy right-handed singlet neutrinos). In the case of Higgs triplets, the Majorana neutrino masses are arbitrary, whereas in the case of heavy singlet neutrinos, an inverted hierarchy is predicted. Lepton-flavor-violation effects, present only in the μ-Ï sector, are analyzed in detail: the LFV Ï-decay rates are predicted below the present bounds by a few orders of magnitude, whereas LFV Higgs decays could allow for a direct test of the model.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
Shao-Long Chen, Michele Frigerio, Ernest Ma,