European Physical Journal C: Particles and Fields (May 2017)

Charmless $$B_{(s)}\rightarrow VV$$ B ( s ) → V V decays in factorization-assisted topological-amplitude approach

  • Chao Wang,
  • Qi-An Zhang,
  • Ying Li,
  • Cai-Dian Lü

DOI
https://doi.org/10.1140/epjc/s10052-017-4889-3
Journal volume & issue
Vol. 77, no. 5
pp. 1 – 13

Abstract

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Abstract Within the factorization-assisted topological-amplitude approach, we studied the 33 charmless $$B_{(s)} \rightarrow VV$$ B ( s ) → V V decays, where V stands for a light vector meson. According to the flavor flows, the amplitude of each process can be decomposed into eight different topologies. In contrast to the conventional flavor diagrammatic approach, we further factorize each topological amplitude into decay constant, form factors and unknown universal parameters. By $$\chi ^2$$ χ 2 fitting 46 experimental observables, we extracted 10 theoretical parameters with $$\chi ^2$$ χ 2 per degree of freedom around 2. Using the fitted parameters, we calculated the branching fractions, polarization fractions, CP asymmetries and relative phases between polarization amplitudes of each decay mode. The decay channels dominated by tree diagram have large branching fractions and large longitudinal polarization fraction. The branching fractions and longitudinal polarization fractions of color-suppressed decays become smaller. Current experimental data of large transverse polarization fractions in the penguin dominant decay channels can be explained by only one transverse amplitude of penguin annihilation diagram. Our predictions of the not yet measured channels can be tested in the ongoing LHCb experiment and the Belle-II experiment in the future.