Lepton Flavour Violation in Models with A4 Flavour Symmetry

Understand

We analyze lepton flavour violating transitions, leptonic magnetic dipole moments (MDMs) and electric dipole moments (EDMs) in a class of models characterized by the flavour symmetry A4 x Z3 x U(1)_{FN}, whose choice is motivated by the approximate tri-bimaximal mixing observed in neutrino oscillations.

• We construct the relevant low-energy effective Lagrangian where these effects are dominated by dimension six operators, suppressed by the scale M of new physics.
• All the flavour breaking effects are universally described by the vacuum expectation values <Phi> of a set of spurions.
• We separately analyze both a supersymmetric and a general case.