Related papers: Polarization Study in B Decays to Vector Final Sta…
Factorizable amplitudes in B decays to light vector meson pairs give a longitudinal polarization satisfying 1- f_L =O(1/m_b^2). This remains formally true when non-factorizable graphs are included in QCD factorization, and is numerically…
We study the charmless rare decays $B \to K^{\ast} K^{\ast}$ within the Perturbative QCD picture. We calculate not only factorizable and non-factorizable diagrams, but also annihilation ones. Our predictions are the following: The…
The recent measurements of large transverse fractions in B \to \phi K^* decays represent a challenge for theory. It was shown that the QCD penguin annihilation could contribute to the transverse amplitudes such that the observation could be…
In this paper, we examine B -> VT decays (V is a vector and T is a tensor meson), whose final-state particles can have transverse or longitudinal polarization. Measurements have been made of B -> \phi K_2^*, and it is found that fT/fL is…
We demonstrate that the polarization fractions of most tree-dominated $B\to VV$ decays can be simply understood by means of kinematics in the heavy-quark or large-energy limit. For example, the longitudinal polarization fractions $R_L$ of…
We resolve the $B\to\phi K^{*}$ polarization puzzle by postulating a smaller $B\to K^*$ form factor $A_0\approx 0.3$ and by adding penguin annihilation and nonfactorizable contributions from the perturbative QCD approach. If this…
We calculate the hard-scattering kernels relevant to the negative-helicity decay amplitude in B decays to two vector mesons in the framework of QCD factorisation. We then perform a comprehensive analysis of the 34 B->VV decays, including…
An important experimental effort has been accomplished in recent years in the measurement of rates, polarization and CP observables in $B$ decays into two light vector mesons. On the theoretical side, after a very consistent effort done…
We provide a comprehensive test of factorization in the heavy-heavy $B$ decays motivated by the recent experimental data from BELLE and BABAR collaborations. The penguin effects are not negligible in the B decays with two pseudoscalar…
The rare decay $B^0 \to \phi\phi$ can occur only via penguin annihilation topology in the standard model. We calculate this channel in the perturbative QCD approach. The predicted branching ratio is very small at ($10^{-8}$). We also give…
We present a detailed study of charmless two-body B decays into final states involving two vector mesons (VV) or two axial-vector mesons (AA) or one vector and one axial-vector meson (VA), within the framework of QCD factorization, where…
We reexamine the branching ratios, $CP$-asymmetries, and other observables in a large number of $B_q\to VV(q=u,d,s)$ decays in the perturbative QCD (PQCD) approach, where $V$ denotes a light vector meson $(\rho, K^*, \omega, \phi)$. The…
We evaluate $B\to K\pi$ decay amplitudes in perturbative QCD picture. It is found that penguin contributions are dynamically enhanced by nearly 50% compared to those assumed in the factorization approximation. It is also shown that…
We compute branching ratios of $B\to K\pi$ decays in the framework of perturbative QCD factorization theorem. Decay amplitudes are classified into the topologies of tree, penguin and annihilation, all of which contain both factorizable and…
We calculate branching ratios for pure penguin decay modes, $B\to \phi K$ decays using perturbative QCD approach. Our results of branching ratios are consistent with the experimental data and larger than those obtained from the naive…
Recently BABAR and Belle have measured anomalous large transverse polarizations in some pure penguin $B \to VV$ decays, which might be inconsistent with the Standard Model expectations. We try to explore its implications for R-parity…
We study the first observed charmless $B\to VV$ modes, the $B\to\phi K^*$ decays, in perturbative QCD formalism. The obtained branching ratios $B(B\to\phi K^*)\sim 15 \times 10^{-6}$ are larger than $\sim 9\times 10^{-6}$ from QCD…
Within the framework of perturbative QCD approach based on $\mathbf{k_T}$ factorization, we investigate the charmless decay mode $B \to K_0^*(1430)\phi$. Under two different scenarios (S1 and S2) for the description of scalar meson…
$B\to\phi K^*$ ($\btos$) is three separate decays, one for each polarization of the final-state vector mesons (one longitudinal, two transverse). It is observed that the fraction of transverse decays, $\fT$, and the fraction of longitudinal…
We study $B_{\small (s)}\to \phi\rho$ decays in a perturbative QCD approach based on $k_T$ factorization. In this approach, we calculate factorizable and non-factorizable contributions, there are no annihilation contributions due to quark…