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arXiv · 0807.2024

$B \to ρ(ω, ϕ) \etap $ Decays and NLO contributions in the pQCD Approach

Abstract

By employing the perturbative QCD (pQCD) factorization approach, we calculated some important next-to-leading-order(NLO) contributions to the two-body charmless hadronic decays $B^+ \to ρ^+ η^{(\prime)}$ and $B^0 \to ρ^0(ω, ϕ) η^{(\prime)}$, induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that (a) for $B^\pm \to ρ^\pm \etap$ decays, the partial NLO contributions to branching ratios are small in magnitude; (b) for $B^0 \to ρ^0(ω,ϕ) \etap$ decays, the NLO contributions can provide significant enhancements to the leading order predictions of their branching ratios; and (c) the pQCD predictions for the CP-violating asymmetries $\acp^{dir}(B^\pm \to ρ^\pm \etap)$ are consistent with the data, while the predicted $\acp(B^0 \to ρ^0(ω)\etap)$ are generally large in magnitude and could be tested by the forthcoming LHCb experiments.

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BibTeXRIS

Zhi-Qing Zhang, Zhen-Jun Xiao. 2008-07-17. $B \to ρ(ω, ϕ) \etap $ Decays and NLO contributions in the pQCD Approach. https://arxiv.org/abs/0807.2024

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