Abstract
Within the factorization-assisted topological-amplitude approach, we studied the 33 charmless B_{(s)} rightarrow VV 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 fitting 46 experimental observables, we extracted 10 theoretical parameters with chi ^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.
Highlights
In contrast to the above approaches based on the perturbative QCD, another idea based on the topological diagrams and flavor SU(3) symmetry was proposed [19–21], where the non-perturbative parameters are extracted directly from the experimental data
No direct power expansion is needed in this approach, flavor SU(3) symmetry is required to reduce the number of free parameters to be fitted from experiments
Some other penguin-dominated strangeness-changing decays, such as B → ρ K ∗ and Bs → φφ, have been found with large transverse polarization fractions. These large unexpected transverse polarization fractions have attracted much theoretical attention with several explanations based on the QCD factorization (QCDF) [36–42], perturbative QCD (PQCD) [43–45], even on the new physics scenarios [46–55]
Summary
In contrast to the above approaches based on the perturbative QCD, another idea based on the topological diagrams and flavor SU(3) symmetry was proposed [19–21], where the non-perturbative parameters are extracted directly from the experimental data. By using some of the well-defined factorization formulas to include most of the SU(3) breaking effects, the theoretical results of the two-body non-leptonic D decays accommodate experimental data very well. These large unexpected transverse polarization fractions have attracted much theoretical attention with several explanations based on the QCDF [36–42], PQCD [43–45], even on the new physics scenarios [46–55] These decays have rich observables, some of which are regarded as good places for testing the SM and searching for possible effects of new physics beyond the SM. To our knowledge, these decays with two vector meson final states have not been studied in the flavor diagram approach.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.