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arXiv · hep-ex/0403039

Search for neutrinoless decays tau -> 3l

Y. Yusa
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Abstract

We have searched for neutrinoless tau lepton decays into three charged leptons using an 87.1 fb^{-1} data sample collected with the Belle detector at the KEKB e^+e^- collider. Since the number of signal candidate events is compatible with that expected from the background, we set 90% confidence level upper limits on the branching fractions in the range (1.9-3.5) x 10^{-7} for various decay modes tau -> l l l where l represents e or mu.

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Y. Yusa. 2004-04-01. Search for neutrinoless decays tau -> 3l. https://doi.org/10.1016/j.physletb.2004.04.002

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