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arXiv · hep-ex/0007042

Search for Decays of B^{0} Mesons into Pairs of Leptons: B{0} -> e^{+}e^{-}, B^{0} -> μ^{+}μ^{-} and B^{0} -> e^{\pm}μ^{\mp}

T. Bergfeld·CLEO Collaboration
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Abstract

We search for the decays of the $B^0$ meson into $e^+e^-$, $μ^+μ^-$ $e^{\pm}μ^{\mp}$ pairs in a sample of $9.7\times 10^6$ $B{\bar B}$ pairs recorded by CLEO detector. No signal is found, and the following upper limits on the corresponding branching fractions are established: $<8.3\times 10^{-7}$, $<6.1\times 10^{-7}$, $< 15\times 10^{-7}$ at 90% confidence level. A new lower limit on the Pati-Salam leptoquark mass $M_{LQ}>27$ TeV is established at 90% confidence level.

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T. Bergfeld, CLEO Collaboration. 2000-07-20. Search for Decays of B^{0} Mesons into Pairs of Leptons: B{0} -> e^{+}e^{-}, B^{0} -> μ^{+}μ^{-} and B^{0} -> e^{\pm}μ^{\mp}. https://doi.org/10.1103/physrevd.62.091102

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