Abstract
In this paper, we calculated the B → (J/Ψ, ηc)K decays in the perturbative QCD (pQCD) factorization approach with the inclusion of the partial next-to-leading order (NLO) contributions. With the inclusion of the significant enhancement from the NLO vertex corrections, the NLO pQCD predictions for the branching ratios agree with the data within 2σ errors: Br(B0 → J/ΨK0) = 5.2+3.5−2.8×10−4, Br(B+ → J/ΨK+) = 5.6+3.7−2.9×10−4, Br(B0 → ηcK0) = 5.5+2.3−2.0×10−4, Br(B+ → ηcK+) = 5.95.2+2.5−2.1×10−4.