24,143 research outputs found

    BcB_c Exclusive Decays to Charmonium and a Light Meson at Next-to-Leading Order Accuracy

    Full text link
    In this paper the next-to-leading order (NLO) corrections to BcB_c meson exclusive decays to S-wave charmonia and light pseudoscalar or vector mesons, i.e. Ο€\pi, KK, ρ\rho, and Kβˆ—K^*, are performed within non-relativistic (NR) QCD approach. The non-factorizable contribution is included, which is absent in traditional naive factorization (NF). And the theoretical uncertainties for their branching ratios are reduced compared with that of direct tree level calculation. Numerical results show that NLO QCD corrections markedly enhance the branching ratio with a K factor of 1.75 for BcΒ±β†’Ξ·cπ±B_{c}^{\pm}\to \eta_{c} \pi^{\pm} and 1.31 for BcΒ±β†’J/ΟˆΟ€Β±B_{c}^{\pm}\to J/\psi \pi^{\pm}. In order to investigate the asymptotic behavior, the analytic form is obtained in the heavy quark limit, i.e. mbβ†’βˆžm_b \to \infty. We note that annihilation topologies contribute trivia in this limit, and the corrections at leading order in z=mc/mbz= m_c/m_b expansion come from form factors and hard spectator interactions. At last, some related phenomenologies are also discussed.Comment: 20 pages, 7 figures and 5 table

    A solitary nodule of the right cheek of a 25-year-old man

    Get PDF
    • …
    corecore