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Observation of the semileptonic decay \( {B}^{+}\to p\overline{p}{\mu}^{+}{\nu}_{\mu } \)

A preprint version of the article is available at arXiv.

Abstract

The Cabibbo-suppressed semileptonic decay \( {B}^{+}\to p\overline{p}{\mu}^{+}{\nu}_{\mu } \) is observed for the first time using a sample of pp collisions corresponding to an integrated luminosity of 1.0, 2.0 and 1.7 fb1 at centre-of-mass energies of 7, 8 and 13 TeV, respectively. The differential branching fraction is measured as a function of the \( p\overline{p} \) invariant mass using the decay mode B+ → J/ψK+ for normalisation. The total branching fraction is measured to be

\( \mathrm{\mathcal{B}}\left({B}^{+}\to p\overline{p}{\mu}^{+}{\nu}_{\mu}\right)=\left({5.27}_{-0.24}^{+0.23}\pm 0.21\pm 0.15\right)\times {10}^{-6}, \)

where the first uncertainty is statistical, the second systematic and the third is from the uncertainty on the branching fraction of the normalisation channel.

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