Observation of the semileptonic decay $B^{+}\to p\overline{p}\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼$

Abstract

The Cabibbo-suppressed semileptonic decay $B^{+}\to p\overline{p}\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼$ is observed for the first time using a sample of $pp$ collisions corresponding to an integrated luminosity of 1.0, 2.0 and 1.7fb${}^{-1}$ at centre-of-mass energies of 7, 8 and 13TeV, respectively. The differential branching fraction is measured as a function of the $p\overline{p}$ invariant mass using the decay mode $B^{+}\to J/\ddot{I}ˆK^{+}$ for normalisation. The total branching fraction is measured to be \begin{align*} \mathcal{B}(B^{+}\to p\overline{p}μ^{+}ν_μ) = (5.27 ^{+0.23}_{-0.24} \pm 0.21 \pm 0.15)\times 10^{-6}, \end{align*} where the first uncertainty is statistical, the second systematic and the third is from the uncertainty on the branching fraction of the normalisation channel.

All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2019-034.html (LHCb public pages)