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arXiv · hep-ex/0211017

Search for neutrinoless tau decays tau -> 3l and tau -> l K0S

Y. Yusa·H. Hayashii·T. Nagamine·A. Yamaguchi
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Abstract

Neutrinoless tau-lepton decays into either three leptons (tau- -> l1- l2 l3) or one lepton and one K0S meson(tau- -> l- K0S) where lepton l means either an electron or muon, have been searched for using 48.6 fb^{-1} of data collected with the Belle detector at the KEKB e+e- collider. No evidence for candidate decays are found in any channel. Therefore we set 90% confidence level upper limits on the branching fraction for 8 different decay modes. These limits are more stringent than those set previously and reach to the 10^{-7} level.

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Y. Yusa, H. Hayashii, T. Nagamine, A. Yamaguchi. 2002-11-07. Search for neutrinoless tau decays tau -> 3l and tau -> l K0S. https://doi.org/10.1016/s0920-5632(03)80312-2

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