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arXiv · 0903.1220

Search for the Rare Leptonic Decays \boldmath{\Blnu} ($\ell=e,μ$)

The BABAR Collaboration·B. Aubert
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Abstract

We have performed a search for the rare leptonic decays \Bp \to \ellp \nul ($l=e,μ$), using data collected at the \FourS resonance by the \babar\ detector at the \pep2 storage ring. In a sample of 468 million \BB pairs we find no evidence for a signal and set an upper limit on the branching fractions $\BR(\bmunu) < 1.0\times10^{-6}$ and $\BR(\benu) < 1.9\times10^{-6}$ at the 90% confidence level, using a Bayesian approach.

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The BABAR Collaboration, B. Aubert. 2009-06-02. Search for the Rare Leptonic Decays \boldmath{\Blnu} ($\ell=e,μ$). https://doi.org/10.1103/physrevd.79.091101

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