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arXiv · 1706.06138

Study of the weak annihilation contributions in charmless $B_s\to VV$ decays

Qin Chang·Xiao-Nan Li·Xin-Qiang Li·Jun-Feng Sun
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Abstract

In this paper, in order to probe the spectator-scattering and weak annihilation contributions in charmless $B_s\to VV$ (where $V$ stands for a light vector meson) decays, we perform the $χ^2$-analyses for the end-point parameters within the QCD factorization framework, under the constraints from the measured $\bar B_{s}\to$$ρ^0ϕ$, $ϕK^{*0}$, $ϕϕ$ and $K^{*0}\bar K^{*0}$ decays. The fitted results indicate that the end-point parameters in the factorizable and nonfactorizable annihilation topologies are non-universal, which is also favored by the charmless $B\to PP$ and $PV$ (where $P$ stands for a light pseudo-scalar meson) decays observed in the previous work. Moreover, the abnormal polarization fractions $f_{L,\bot}(\bar B_{s}\to K^{*0}\bar K^{*0})=(20.1\pm7.0)\%\,,(58.4\pm8.5)\%$ measured by the LHCb collaboration can be reconciled through the weak annihilation corrections. However, the branching ratio of $\bar B_{s}\toϕK^{*0}$ decay exhibits a tension between the data and theoretical result, which dominates the contributions to $χ_{\rm min}^2$ in the fits. Using the fitted end-point parameters, we update the theoretical results for the charmless $B_s\to VV$ decays, which will be further tested by the LHCb and Belle-II experiments in the near future.

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Qin Chang, Xiao-Nan Li, Xin-Qiang Li, Jun-Feng Sun. 2017-06-19. Study of the weak annihilation contributions in charmless $B_s\to VV$ decays. https://doi.org/10.1140/epjc%2Fs10052-017-4980-9

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