B(s) → ηc(P,V) decays and effects of the next-to-leading order contributions in the perturbative QCD approach

Abstract

By employing the perturbative QCD (PQCD) factorization approach, we studied the sixteen B/Bs→ηc(π,K,η(′),ρ,K⁎,ω,ϕ) decays with the inclusion of the currently known next-to-leading order (NLO) contributions. We found the following main points: (a) for the five measured B→ηc(K,K⁎) and Bs→ηcϕ decays, the NLO contributions can provide (80–180)% enhancements to the leading order (LO) PQCD predictions of their branching ratios, which play an important role to help us to interpret the data; (b) for the seven ratios R1,⋯,7 of the branching ratios defined among the properly selected pair of the considered decay modes, the PQCD predictions for the values of R3,4,5 agree well with those currently available measurements from BaBar and Belle Collaboration; (c) for B0→ηcKS0 decay, the PQCD predictions for both the direct and mixing induced CP asymmetries do agree very well with the measured values within errors; and (d) the PQCD predictions for ratios R1,2 and R6,7 also agree with the general expectations and will be tested by the future experiments.