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arXiv · 0801.2475

Search for lepton-flavor-violating $\tau\to\ell V^0$ decays at Belle

Y. Nishio·K. Inami·T. Ohshima
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Abstract

We have searched for neutrinoless $\tau$ lepton decays into $\ell$ and $V^0$, where $\ell$ stands for an electron or muon, and $V^0$ for a vector meson ($\phi$, $\omega$, $K^{*0}$, $\bar{K}^{*0}$ or $\rho^0$), using 543 fb$^{-1}$ of data collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. No excess of signal events over the expected background has been observed, and we set upper limits on the branching fractions in the range $(5.9-18) \times 10^{-8}$ at the 90% confidence level. These upper limits include the first results for the $\ell \omega$ mode as well as new limits that are significantly more restrictive than our previous results for the $\ell \phi$, $\ell K^{*0}$, $\ell \bar{K}^{*0}$ and $\ell \rho^0$ modes.

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Y. Nishio, K. Inami, T. Ohshima. 2008-01-16. Search for lepton-flavor-violating $\tau\to\ell V^0$ decays at Belle. https://doi.org/10.1016/j.physletb.2008.05.012

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