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arXiv · hep-ex/0007057

A Search for $B\to τν$

T. E. Browder·CLEO Collaboration
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Abstract

We report results of a search for $B\toτν$ in a sample of 9.7 million charged $B$ meson decays. The search uses both $πν$ and $\ellν\barν$ decay modes of the $τ$, and demands exclusive reconstruction of the companion $\bar B$ decay to suppress background. We set an upper limit on the branching fraction ${\cal B}(B\to τν) < 8.4\times 10^{-4}$ at 90% confidence level. With slight modification to the analysis we also establish ${\cal B}(B^\pm\to K^\pmν\barν) < 2.4\times 10^{-4}$ at 90% confidence level.

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T. E. Browder, CLEO Collaboration. 2000-07-27. A Search for $B\to τν$. https://doi.org/10.1103/physrevlett.86.2950

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