Related papers: Possible complex annihilation and B -> K pi direct…
We compute standard model penguin amplitudes in nonleptonic B-decays to light charmless mesons using tree amplitude data to fix hadronic parameters. The leading calculation is carried out for the alphas(mb) penguin contributions from charm…
In our subgroup, we focused on penguin physics from various different angles. Our discussions included: (1) A method to extract one of the angles of the unitarity triangle $\phi_2$; (2) Methods to extract $\phi_3$ from $B\to K\pi$ decays;…
B meson rare decays ($B\to K(K^{*})l\bar l$ and $B\to K^*\gamma$) are analyzed in the framework of effective field theory of heavy quarks. The semileptonic and penguin type form factors for these decays are calculated by using the light…
I review the recent progress on the perturbative QCD approach to exclusive $B$ meson decays, discussing the comparison of collinear and $k_T$ factorizations, the CP asymmetry in the $B^0\to\pi^+\pi^-$ decay, penguin enhancement, the…
Direct CP violation in charmless three-body hadronic decays of $B$ mesons is studied within the framework of a simple model based on the factorization approach. Three-body decays of heavy mesons receive both resonant and nonresonant…
The direct CP asymmetry $a_{CP}^{\mathrm{dir}}(D^0\rightarrow K_SK_S)$ involves exchange diagrams which are induced at tree level in the Standard Model. Since the corresponding topological amplitude $E_{KK}$ can be large, $D^0\rightarrow…
The pure annihilation type decays $B^0_d\to\phi\gamma$ and $B_s\to\rho\gamma$ receive only color suppressed penguin contributions with a very small branching ratio in the standard model. When we include the previously neglected…
Penguin effects in the CP asymmetries of $B^0_d\rightarrow \pi^+\pi^-$ , $\bd\rightarrow\rho^{\pm}\pi^{\mp}$ and $\bd\rightarrow a^{\pm}_1 \pi^{\mp}$ are studied as function of the CKM unitarity triangle $\alpha$. Despite a fairly small…
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…
The large branching ratios for $B \to K\pi$ decays as observed by the CLEO Collaboration indicate that penguin interactions contribute a major part to the decay rates and provide an interference between the Cabibbo-suppressed tree and…
Direct CP violation in B^0-> K^+\pi^- decay has emerged at -10% level, but the asymmetry in B^+ -> K^+\pi^0 mode is consistent with zero. This difference points towards possible New Physics in the electroweak penguin operator. We point out…
In a large class of models for Weakly Interacting Massive Particles (WIMPs), the WIMP mass $M$ lies far above the weak scale $m_W$. This work identifies universal Sudakov-type logarithms $\sim \alpha \log^2 (2\,M/m_W)$ that spoil the naive…
The effect of the penguin amplitude on extracting $\alpha$ from CP asymmetries in $B^0\to \rho^+\rho^-$ decays is studied using information on the SU(3)-related penguin amplitude in $B^+\to K^{*0}\rho^+$. Conservative bounds on…
The QCD factorization (QCDF) method usually contains infrared divergences which introduce large model dependence to its predictions on charmless B decays. The amplitudes of charmless B decays can be decomposed into "tree" and "penguin"…
The decay $B^0 \to K^0 \pi^0$, dominated by a $b \to s$ penguin amplitude, holds the potential for exhibiting new physics in this amplitude. In the pure QCD penguin limit one expects $\ckp = 0$ and $\skp = \sin 2 \beta$ for the coefficients…
Isospin structure of gluon mediated or strong penguin is significantly altered when the full electroweak corrections are included. This has the consequence that some previous analyses which relied on a simple isospin structure in charmless…
We calculate direct CP-violating observables in charged $B\to VV$ decays arising from the interference of amplitudes with different strong and CKM phases. The perturbative strong phases develop at order $\alpha_s$ from absorptive parts of…
The ampitude of the $B\to\rho\gamma$ decay induced by the flavour-changing neutral currents contains the penguin contribution and the weak-annihilation contribution generated by the 4-quark operators in the effective Hamiltonian. The…
We discuss the theoretical interpretation of the $B\to\pi K$ system in the light of new data. Using the branching ratio and direct CP asymmetry of $B^0_d\to\pi^-K^+$, the picture of the direct CP violation in $B_d^0\to\pi^+\pi^-$ could be…
Including corrections of order $O(m_{K^*}/m_B)$, we present an analysis of photonic penguin contributions to the decay $B\to K^* \gamma$ in the perturbative QCD framework. Employing several models of the meson wave functions, we demonstrate…