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The relative abundance of the three decay modes $B_d to D^- K^+$, $B_d to D^- pi^+$ and $B_s to D_s^- pi^+$ produced in 7 TeV $pp$ collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb$^{-1}$. The branching fraction of $B_d to D^- K^+$ is found to be $cal B (B_d to D^- K^+) = (2.01 pm 0.18^{textrm{stat}} pm 0.14^{textrm{syst}})times 10^{-4}$. The ratio of fragmentation fractions fsfdt is determined through the relative abundance of $B_s to D_s^- pi^+$ to $B_d to D^- K^+$ and $B_d to D^-pi^+$, leading to $f_s/f_d = 0.253 pm 0.017 pm 0.017 pm 0.020$, where the uncertainties are statistical, systematic, and theoretical respectively.
The asymmetry in the production cross-section sigma of D+/- mesons, A_P = (sigma(D+) - sigma(D-))/(sigma(D+) + sigma(D-)), is measured in bins of pseudorapidity eta and transverse momentum p_T within the acceptance of the LHCb detector. The result is
The ratio of the $B^0_s$ and $B^0$ fragmentation fractions, $f_s/f_d$, in proton-proton collisions at the LHC, is obtained as a function of $B$-meson transverse momentum and collision centre-of-mass energy from the combined analysis of different $B$-
Using 13.53/fb of CLEO data, we have measured the ratios of the branching fractions R+(e) = BF(D+ --> K*0bar e+ nu_e) / BF(D+ --> K- pi+ pi+), R+(mu) = BF(D+ --> K*0bar mu+ nu_mu) / BF(D+ --> K- pi+ pi+) and the combined branching fraction ratio R+(l
We report a study of the decay $D^0 to K^0_S K^0_S$ using 921~fb$^{-1}$ of data collected at or near the $Upsilon(4S)$ and $Upsilon(5S)$ resonances with the Belle detector at the KEKB asymmetric energy $e^+e^-$ collider. The measured time-integrated