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We present new results from the study of B decays at SLD: a measurement of the inclusive double-charm branching fraction in B-hadron decays and a search for the rare exclusive charmless decays B+ --> Rho0 Pi+(K+) and B+ --> K*0 Pi+(K+). Using a novel technique which consists of counting charged kaons produced at the secondary (B) vertex and the tertiary (D) vertex, we measure BR(B-->DDbarX) = 0.188 +- 0.025(stat) +- 0.059(syst). Another technique, based on the comparison of the charge of the D vertex to the flavor of the B hadron at production, yields a consistent result. In the search for rare exclusive B+ decays, no candidates were found and competitive branching ratio upper limits are derived.
We report on preliminary measurements of branching fractions, charge-parity-violating asymmetries, and longitudinal polarization fractions in charmless bottom-meson decays from the Belle~II experiment. We use samples of electron-positron collisions collected in 2019 and 2020 at the $Upsilon(4S)$ resonance, corresponding to integrated luminosities of up to 62.8 ${rm fb^{-1}}$. The results are compatible with known values, indicating good understanding of early detector performance.
Penguin transitions play a key role in the search of New Physics hints in the heavy flavor sector. During the last decade CDF has been exploring this opportunity with a rich study of two--body charmless decays of neutral B mesons into charged final--state particles. After briefly introducing the aspects of this physics peculiar to the hadron collision environment, I report on two interesting results: the first polarization measurement of the B^0_s --> phi phi decay and the update of the B^0(_s) --> h^+h^- decays analysis.
We report on recent measurements of the branching fractions (BFs) for the decay channels B^0 -> {pi}^-l^+{ u}, B^+ -> {pi}^0l^+{ u}, B^+ -> {eta}l^+{ u}, B^+ -> {eta}l^+{ u}, B^0 -> {rho}^-l^+{ u} and B^+ -> {rho}^0l^+{ u}. We obtain very precise values of the total branching fractions for these decays, as well as partial branching fractions as a function of q^2 for the decay channels B^0 -> {pi}^-l^+{ u}, B^+ -> {eta}l^+{ u} and B^0 -> {rho}^-l^+{ u}. In particular, we use the partial branching fractions of the B^0 -> {pi}^-l^+{ u} decay channel and form-factor calculations to extract several values of |V_{ub}|. When we compared these values of |V_{ub}| to the one measured in inclusive semileptonic B decay, we find that two of them are consistent, within large theoretical uncertainties.
An algorithm is described for tagging the flavour content at production of neutral $B$ mesons in the LHCb experiment. The algorithm exploits the correlation of the flavour of a $B$ meson with the charge of a reconstructed secondary charm hadron from the decay of the other $b$ hadron produced in the proton-proton collision. Charm hadron candidates are identified in a number of fully or partially reconstructed Cabibbo-favoured decay modes. The algorithm is calibrated on the self-tagged decay modes $B^+ to J/psi , K^+$ and $B^0 to J/psi , K^{*0}$ using $3.0mathrm{,fb}^{-1}$ of data collected by the LHCb experiment at $pp$ centre-of-mass energies of $7mathrm{,TeV}$ and $8mathrm{,TeV}$. Its tagging power on these samples of $B to J/psi , X$ decays is $(0.30 pm 0.01 pm 0.01) %$.
We report measurements of the branching fractions for the decays B->D_s1(2536)+ anti-D(*), where anti-D(*) is anti-D0, D- or D*-, and study of B->X(3872) K with X(3872) decaying to D*0 anti-D0 using a sample of 657 million B anti-B pairs recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.