Anatomy of Bs → VV decays and effects of next-to-leading order contributions in the perturbative QCD factorization approach

Da-Cheng Yan,Xin Liu,Zhen-Jun Xiao

doi:10.1016/j.nuclphysb.2018.08.002

Da-Cheng Yan, Xin Liu + Show 1 more

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https://doi.org/10.1016/j.nuclphysb.2018.08.002

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Abstract

By employing the perturbative QCD (PQCD) factorization approach, we calculated the branching ratios, CP-violating asymmetries, the longitudinal and transverse polarization fractions and other physical observables of the thirteen charmless hadronic B¯s0→VV decays with the inclusion of all currently known next-to-leading order (NLO) contributions. We focused on the examination of the effects of all those currently known NLO contributions and found that: (a) for the measured decays B¯s0→ϕϕ,K⁎0ϕ,K¯⁎0K⁎0 and ρ0ϕ, the NLO contributions can provide ∼20% to ∼40% enhancements to the leading order (LO) PQCD predictions of their CP-averaged branching ratios, and consequently the agreement between the PQCD predictions and the measured values are improved effectively after the inclusion of the NLO contributions; (b) for the measured decays, the NLO corrections to the LO PQCD predictions for (fL,f⊥) and (ϕ‖,ϕ⊥) are generally small in size, but the weak penguin annihilation contributions play an important role in understanding the data about their decay rates, fL and f⊥; (c) the NLO PQCD predictions for above mentioned physical observables do agree with the measured ones and the theoretical predictions from the QCDF, SCET and FAT approaches; (d) for other considered Bs0→VV decays, the NLO PQCD predictions for their decay rates and other physical observables are also basically consistent with the theoretical predictions from other popular approaches, future precision measurements could help us to test or examine these predictions.

Highlights

During the past three decades, the two-body charmless hadronic Bs → V V decays, with V being the light vector mesons ρ, K∗, φ and ω, have been studied by many authors based on rather different factorization approaches [1,2,3,4,5,6,7,8,9,10,11]
We aim to examine the effects of all currently known next-to-leading order (NLO) contributions to the considered Bs0 → V V decay modes in the perturbative QCD (PQCD) approach to see whether one can improve the consistency between the theory and the experiment in the Stand Model (SM) or not, which would be help for us to judge the necessity of the exotic new physics beyond the SM
We studied the tao-body charmless hadronic decays Bs0 → V V ( here V = (ρ, K∗, φ, ω)) by employing the PQCD factorization approach with the inclusion of all currently known NLO contributions, such as the NLO vertex corrections, the quark loop effects and the chromo-magnetic penguin diagrams etc

Summary

Introduction

During the past three decades, the two-body charmless hadronic Bs → V V decays, with V being the light vector mesons ρ, K∗, φ and ω, have been studied by many authors based on rather different factorization approaches [1,2,3,4,5,6,7,8,9,10,11]. Several such decay modes, such as Bs0 → φφ decay, have been observed by CDF and LHCb experiments [12,13,14,15,16,17,18,19,20,21].

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