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arXiv · 0809.1778

Evidence for $B^0 \to χ_{c1} π^0$ at Belle

Belle Collaboration·R. Kumar·J. B. Singh
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Abstract

We present a measurement of the branching fraction for the Cabibbo- and color-suppressed $B^0 \to χ_{c1}π^0$ decay based on a data sample of $657\times 10^6$ $B\bar B$ events collected at the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We observe a signal of $40\pm9$ events with a significance of $4.7σ$ including systematic uncertainties. The measured branching fraction is $\mathcal {B}(B^0 \to χ_{c1} π^0) = (1.12\pm 0.25(\rm {stat.})\pm 0.12({\rm syst.}))\times 10^{-5}$.

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Belle Collaboration, R. Kumar, J. B. Singh. 2008-09-11. Evidence for $B^0 \to χ_{c1} π^0$ at Belle. https://doi.org/10.1103/physrevd.78.091104

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