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arXiv · hep-ph/9711348

Atmospheric Neutrino Oscillation and Large Lepton-Flavour Violation in the SUSY SU(5) GUT

J. Hisano·Daisuke Nomura·T. Yanagida
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Abstract

The atmospheric neutrino anomaly reported by the super-Kamiokande collaboration suggests existence of a large flavour violating Yukawa coupling in the lepton sector. We discuss lepton-flavour violation at low energies in the framework of the supersymmetric SU(5)_{GUT} model with right-handed neutrinos. We find that for a wide range of parameter space suggested from the atmospheric neutrino anomaly, if the tau-neutrino Yukawa coupling is as large as that of top quark, lower bounds of the branching ratios of mu -> e gamma, tau -> mu gamma, and the mu-e conversion rate on $^{48}_{22}Ti$ become around 10^{-14}, 10^{-9}, and 10^{-16}, respectively. These reaction rates may be in the region accessible by near future experiments.

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J. Hisano, Daisuke Nomura, T. Yanagida. 1997-11-17. Atmospheric Neutrino Oscillation and Large Lepton-Flavour Violation in the SUSY SU(5) GUT. https://doi.org/10.1016/s0370-2693(98)00929-0

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