Measurement of the branching fraction and $C\text{\hspace{0.17em}⁣}P$ asymmetry in $B^{+}\to J\mathrm{/}\psi {\rho }^{+}$ decays

The branching fraction and direct $C\text{\hspace{0.17em}⁣}P$ asymmetry of the decay $B^{+}\to J\mathrm{/}\psi {\rho }^{+}$ are measured using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7 and 8 TeV, corresponding to a total integrated luminosity of 3$f{b}^{-1}$. The following results are obtained: \begin{align} $\mathcal{B}$(B^{+}\rightarrow J/\psi \rho^{+}) &= (3.81 ^{+0.25}{-0.24} \pm 0.35) \times 10^{-5}, \nonumber \ $\mathcal{A}$^{C!P} (B^{+}\rightarrow J/\psi \rho^{+}) &= -0.045^{+0.056}{-0.057} \pm 0.008, \nonumber \end{align} where the first uncertainties are statistical and the second systematic. Both measurements are the most precise to date.