Flavour Models with Three Higgs Generations
  We construct models with a spontaneously broken $SU(3)_F$ flavour symmetry where three generations of Higgs multiplets transform in a flavour-triplet representation. The models are embedded in a supersymmetric Pati-Salam GUT framework, which includes left-right symmetry. We study the possible flavon representations and show that a model with flavons in the decuplet representation is able to reproduce the hierarchy structure of the quark and lepton mass and mixing matrices. This result requires no additional structure or fine-tunings except for an extra $Z_4$ discrete symmetry in the superpotential. 
Florian Hartmann, Wolfgang Kilian
hep-ph