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On Lepton Flavor Violation in Tau Decays

G. Cvetic·C. Dib·C. S. Kim·J. D. Kim
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Abstract

We study lepton flavor violation (LFV) in tau decays induced by heavy Majorana neutrinos within two models: (I) the Standard Model with additional right-handed heavy Majorana neutrinos, i.e., a typical seesaw-type model; (II) the Standard Model with left-handed and right-handed neutral singlets, which are inspired by certain scenarios of SO(10)models and heterotic superstring models with E_6 symmetry. We calculate various LFV branching ratios and a T-odd asymmetry. The seesaw Model I predicts very small branching ratios for LFV processes in most of the parameter space, although in a very restricted parameter region it can reach maximal branching ratios Br(tau to mu gamma) approx 10^-9 and Br(tau to 3mu) approx 10^-10. In contrast, Model II may show branching ratios Br(tau to e gamma) approx 10^-8 and Br(tau to 3e) < 10^-9, over a sizable region of the parameter space, large enough to be tested by experiments in the near future.

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G. Cvetic, C. Dib, C. S. Kim, J. D. Kim. 2002-06-27. On Lepton Flavor Violation in Tau Decays. https://doi.org/10.1103/physrevd.66.034008%2010.1103%2Fphysrevd.68.059901

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