QCD corrections to B → J / ψ + anything

We calculate the branching ratio for B → J/ψ + anything , within the colorsinglet approximation for J/ψ production, but including perturbative QCD corrections beyond the leading logarithm approximation. Such higher order corrections are necessary, in order to obtain a result that is not strongly dependent on the renormalization scale. As in the earlier work of Bergström and Ernström, we use a double expansion in αs and in the small ratio of Wilson coefficients L0/L2, to identify the dominant terms in the decay amplitude. We complete their work by calculating all the leading order terms in this double expansion. The predicted branching ratio is then B(B → J/ψ + anything) = 0.9 −0.3 × 10−3, which is well below the experimental value Bexp = (0.80 ± 0.08)%. This confirms the suspicion that non-perturbative corrections to the color-singlet approximation for J/ψ production in B decays are important. PACS: 13.25.Hw, 12.38.Bx, 14.40.Gx