B() → η(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 / B s → η c ( 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 → η c ( K , K ⁎ ) and B s → η c ϕ 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 R 1 , ⋯ , 7 of the branching ratios defined among the properly selected pair of the considered decay modes, the PQCD predictions for the values of R 3 , 4 , 5 agree well with those currently available measurements from BaBar and Belle Collaboration; (c) for B 0 → η c K S 0 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 R 1 , 2 and R 6 , 7 also agree with the general expectations and will be tested by the future experiments.