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Search for Lepton Flavor Violating tau- Decays Including with a K0s Meson

Y. Miyazaki
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Abstract

We have searched for the lepton flavor violating decays $τ^-\to \ell^-\ks$ ($\ell = e {or} μ$), using a data sample of 281 fb$^{-1}$ collected with the Belle detector at the KEKB $e^+e^-$ asymmetric-energy collider. No evidence for a signal was found in either of the decay modes, and we set the following upper limits for the branching fractions: ${\cal{B}}(τ^-\to e^-\ks) < 5.6\times 10^{-8}$ and ${\cal{B}}(τ^-\to μ^-\ks) < 4.9\times 10^{-8}$ at the 90% confidence level. These results improve the previously published limits set by the CLEO collaboration by factors of 16 and 19, respectively.

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Y. Miyazaki. 2006-05-09. Search for Lepton Flavor Violating tau- Decays Including with a K0s Meson. https://doi.org/10.1016/j.physletb.2006.05.086

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