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arXiv · hep-ex/0609047

Observation of the decay $B^0 \to J/ψη$

M. -C. Chang
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Abstract

We report the first observation of $B^0 \to J/ψη$ decay. These results are obtained from a data sample that contains 449 million $B\bar{B}$ pairs accumulated at the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. We observe a signal with a significance of 8.1$σ$ and obtain a branching fraction of (9.5 $\pm$ 1.7 (stat) $\pm$ 0.8 (syst))$\times 10^{-6}$.

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M. -C. Chang. 2007-01-01. Observation of the decay $B^0 \to J/ψη$. https://doi.org/10.1103/physrevlett.98.131803

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