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Yukawa Matrix for the Neutrino and Lepton Flavour Violation

S. Kanemura·K. Matsuda·T. Ota·T. Shindou·E. Takasugi·K. Tsumura
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Abstract

We estimate the magnitude of Lepton Flavour Violation (LFV) from the phase of the neutrino Yukawa matrix. In the minimal supersymmetric standard model with right-handed neutrinos, the LFV processes l_i \to l_j γcan appear through the slepton mixing, which comes from the renormalization group effect on the right-handed neutrino Yukawa interaction between the Grand Unified Theory scale and the heavy right-handed neutrino mass scale. Two types of phases exist in the neutrino Yukawa matrix. One is the Majorana phase, which can change the magnitude of the LFV branching ratios by a few factor. The other phases relate for the size of the Yukawa hierarchy and its phase effect can change the LFV branching ratios by several orders of magnitude.

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S. Kanemura, K. Matsuda, T. Ota, T. Shindou, E. Takasugi, K. Tsumura. 2004-11-18. Yukawa Matrix for the Neutrino and Lepton Flavour Violation. https://doi.org/10.1016/j.nuclphysbps.2005.05.068

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