347 research outputs found

    B-> K photon photon via intermediate eta'

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    We examine our previous conjecture that the eta' intermediate resonance has the dominant role in the long distance contributions to B decay into two photons and a strange final state hadron. We calculate the branching ratio of the exclusive B-> K eta'-> K photon photon decay using the nonspectator mechanism for eta' production in charmless hadronic B decays. It is shown that the obtained branching ratio B^eta'(B-> K\gamma\gamma)~ 8.7 X 10^{-7} is more than twice as large as the eta_c contribution to this decay mode.Comment: 6 pages, latex, no figure

    Dynamical spin effects in the pion

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    We take into account dynamical spin effects in the holographic light-front pion wavefunction in order to predict the pion radius, decay constant, the pion electromagnetic and photon-to-pion transition form factors. We report a striking improvement in the description of all data.Comment: 4 pages, 2 figures. Proceedings Contribution for the 9th International Workshop on Diffraction in High Energy Physics (Diffraction 2016), Santa Tecla di Acireale, Catania, Italy, September 2-8, 201

    Spectator Effects in the Decay B -> K \gamma \gamma

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    We report the results of the first computation related to the study of the spectator effects in the rare decay mode B→KγγB\to K \gamma \gamma within the framework of Standard Model. It is found that the account of these effects results in the enhancement factor for the short-distance reducible contribution to the branching ratio.Comment: 5 pages, 5 figures, RevTeX

    Pade-Improved Estimate of Perturbative Contributions to Inclusive Semileptonic b→ub\to u Decays

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    Pade-approximant methods are used to estimate the three-loop perturbative contributions to the inclusive semileptonic b→ub \to u decay rate. These improved estimates of the decay rate reduce the theoretical uncertainty in the extraction of the CKM matrix element ∣Vub∣|V_{ub}| from the measured inclusive semileptonic branching ratio.Comment: 3 pages, latex, write-up of talk presented at DPF 200
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