Measurement of b-hadron branching fractions for two-body decays into charmless charged hadrons

Based on data corresponding to an integrated luminosity of 0.37 fb ^-1 collected by the LHCb experiment in 2011, the following ratios of branching fractions are measured: B(B⁰ → π⁺π ^-) / B(B⁰ → K⁺π^-) = 0.262 ± 0.009 ± 0.017; (fs/fd) B(B_s⁰ → K ⁺K^-) / B(B⁰ → K⁺π ^-) = 0.316 ± 0.009 ± 0.019; (fs/fd) B(B _s⁰ → π⁺K^-) / B(B⁰ → K⁺π^-) = 0.074 ± 0.006 ± 0.006; (fd/fs) ± B(B⁰ → K⁺K^-) / B(B _s⁰ → K⁺K^-) = 0.018 _-0.007 +-0.007 ± 0.009; (fs/fd) B(B_s⁰ → π⁺π^-) / B(B⁰ → π⁺π^-) = 0.050 _-0.009 ^+0.011 ± 0.004; BΛ_b⁰ → pπ^-) / BΛ_b⁰ → pK^-) = 0.86 ± 0.08 ± 0.05; where the πrst uncertainties are statistical and the second systematic. Using the current world average of B(B⁰ → K ⁺π^-π and the ratio of the strange to light neutral B meson production fs/fd measured by LHCb, we obtain: B(B⁰ → π⁺π^-) = (5.08 ± 0.17 ± 0.37) × 10^-6; B(B_s⁰ → K⁺K^-) = (23.0 ± 0.7 ± 2.3) × 10^-6; B(B_s ⁰ → π⁺K^-) = (5.4 ± 0.4 ± 0.6) × 10^-6; B(B⁰ → K⁺K^-) = (0.11 _-0.04^+0.05 ± 0.06) × 10 ^-6; B(B_s⁰ → π⁺π ^-) = (0.95 _-0.17^+0.21 ± 0.13) × 10^-6. The measurements of B(B_s⁰ → K ⁺K^-), B(B_s⁰ → π⁺K^-) and B(B⁰ → K⁺K ^-) are the most precise to date. The decay mode B_s ⁰ → π⁺π^- is observed for the first time with a significance of more than 5σ. Copyright CERN.