Charged Lepton Flavour Violating Radiative Decays $\ell_i \to \ell_j + \gamma$ in See-Saw Models with $A_4$ Symmetry

C. Hagedorn; E. Molinaro; S. T. Petcov

doi:10.1007/jhep02(2010)047

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arXiv · 0911.3605

Charged Lepton Flavour Violating Radiative Decays $\ell_i \to \ell_j + \gamma$ in See-Saw Models with $A_4$ Symmetry

C. Hagedorn·E. Molinaro·S. T. Petcov

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Abstract

The charged lepton flavour violating (LFV) radiative decays, $\mu\to e+\gamma$, $\tau\to \mu+\gamma$ and $\tau\to e +\gamma$ are investigated in a class of supersymmetric $A_4$ models with three heavy right-handed (RH) Majorana neutrinos, in which the lepton (neutrino) mixing is predicted to leading order (LO) to be tri-bimaximal. The light neutrino masses are generated via the type I see-saw mechanism. The analysis is done within the framework of the minimal supergravity (mSUGRA) scenario, which provides flavour universal boundary conditions at the scale of grand unification $M_X \approx 2 \times 10^{16}$ GeV. Detailed predictions for the rates of the three LFV decays are obtained in two explicit realisations of the $A_4$ models due to Altarelli and Feruglio and Altarelli and Meloni, respectively.

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C. Hagedorn, E. Molinaro, S. T. Petcov. 2009-11-18. Charged Lepton Flavour Violating Radiative Decays $\ell_i \to \ell_j + \gamma$ in See-Saw Models with $A_4$ Symmetry. https://doi.org/10.1007/jhep02(2010)047

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