Lepton flavour violation in a supersymmetric model with image flavour symmetry Original Research Article

We compute the branching ratios for image, image and image in a supersymmetric model invariant under the flavour symmetry group image, in which near tri-bimaximal lepton mixing is naturally predicted. At leading order in the small symmetry breaking parameter u, which is of the same order as the reactor mixing angle image, we find that the branching ratios generically scale as image. Applying the current bound on the branching ratio of image shows that small values of u or image are preferred in the model for mass parameters image and image smaller than 1000 GeV. The bound expected from the on-going MEG experiment will provide a severe constraint on the parameter space of the model either enforcing image and small image or image and image above 1000 GeV. In the special case of universal soft supersymmetry breaking terms in the flavon sector a cancellation takes place in the amplitudes and the branching ratios scale as image, allowing for smaller slepton masses. The branching ratios for image and image are predicted to be of the same order as the one for image, which precludes the possibility of observing these τ decays in the near future.