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arXiv · hep-ex/9704010

Search for Neutrinoless $τ$ Decays Involving $π^{0}$ or $η$ Mesons

CLEO Collaboration·G. Bonvicini et al
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Abstract

We have searched for lepton family number violating decays of the $τ$ lepton using final states with an electron or a muon and one or more $π^0$ or $η$ mesons but no neutrinos. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) and correspond to an integrated luminosity of 4.68 $fb^{-1}$. No evidence for signals was found, resulting in much improved limits on the branching fractions for the one-meson modes and the first upper limits for the two-meson modes.

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CLEO Collaboration, G. Bonvicini et al. 1997-04-18. Search for Neutrinoless $τ$ Decays Involving $π^{0}$ or $η$ Mesons. https://doi.org/10.1103/physrevlett.79.1221

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