Related papers: Large electroweak penguin contribution in B --> K …
Using the next-to-leading order low energy effective Hamiltonian for $\Delta B=1$ transitions, the effects of electroweak penguin operators in some two-body decay modes of $B_s^0$ meson are estimated in the Standard Model (SM). We find that…
B-meson decays play an important role in flavour physics. The $B \rightarrow \pi K$ decays are dominated by QCD loop diagrams (penguins) but also electroweak penguins, where New Physics may enter, have a significant impact on the decay…
We report on recent progress in studying two aspects of $B$ physics, in which penguin amplitudes play an important role: (1) Bounds on penguin pollution in $B^0(t) \to \pi^+\pi^-$ constraining CKM parameters, and a lower bound on $B^0 \to…
The $B\to\pi K$ decays with significant electroweak penguin contributions show a puzzling pattern. We explore this "$B\to\pi K$ puzzle" through a systematic strategy. The starting point, which is essentially unaffected by electroweak…
Measurements of the combined branching ratios for $B^\pm \to \pi^\pm K$ and $B_d \to \pi^\mp K^\pm$ allow interesting constraints on the CKM angle $\gamma$, the ratio $r \equiv |T'|/|P'|$ of the current-current and penguin operator…
We apply the quasi-elastic assumption of the strong final state interactions to describe the B to pi-pi and B to pi-K branching ratios and CP asymmetries and derive bounds on gamma. We find that small electroweak penguins contributions and…
Using the next-to-leading order low energy effective Hamiltonian for $|\Delta B|=1$, $\Delta C=\Delta U=0$ transitions, the contributions of electroweak penguin operators in $ B^-(\overline {B_d^0})\rightarrow PP$ and $PV$ decays are…
The recent observation of B_d -> pi^0 pi^0 at the B factories with a surprisingly large branching ratio represents a challenge for theory, and complements the amazingly small B_d -> pi^+ pi^- rate. We point out that all puzzling B -> pi pi…
Though QCD Factorization(QCDF) could produce sufficiently large $B\to K\pi$ branching ratios close to experiments, the predicted direct CP asymmetry in ${\bar B}^{0}\to K^{+}\pi^{-}$ decay is however still quite below experiment, even with…
It is argued that, in the presence of soft final-state interactions, the diagrammatic amplitude approach adopted in many analyses of hadronic B decays into light mesons can be misleading when used to deduce the unimportance of certain decay…
A general parametrization of the $B^+\to\pi^+ K^0$ and $B_d^0\to\pi^- K^+$ decay amplitudes is presented. It relies only on the isospin symmetry of strong interactions and the phase structure of the Standard Model and involves no…
Recent experiments suggest that certain B -> pi K branching ratios are inconsistent with the standard model expectations. We show that a flavor-changing Z' provides a solution to the problem. Electroweak penguin amplitudes are enhanced by…
Motivated by the recent experimental data, we have revisited the $B\to \pi K,\pi \pi$ decays in the framework of QCD factorization, with inclusion of the important strong penguin corrections of order $\alpha_s^2$ induced by $b\to D g^\ast…
Using the $SU(3)$ flavour symmetry of strong interactions, we propose strategies for extracting both the CKM-angle $\gamma$ and the $\bar b\to\bar uu\bar s$ tree-level amplitude $T'$. We present also an approximate approach using the…
In the light of new experimental results on B -> K pi decays, we critically study the decay processes B -> K pi in a phenomenological way. Using the quark diagram approach and the currently available data, we determine the allowed values of…
We present estimates of the charming penguin contribution to B => K pi, pi pi,K eta, K eta' decays due to intermediate charmed meson states. We find that this contribution is indeed significant for B => K pi decays, and its inclusion,…
We summarize a recent strategy for a global analysis of the B -> pi pi, pi K systems and rare decays. We find that the present B -> pi pi and B -> pi K data cannot be simultaneously described in the Standard Model. In a simple extension in…
The high precision to which the standard model has been confirmed implies that new physics effects have to be small in the observed processes. Together with the outstanding precision expected from present and future collider experiments…
The 2.5 sigma discrepancy between theory and experiment observed in the difference A_CP(B^- --> pi^0 K^-)-A_CP(Bbar^0 --> pi^+ K^-) can be explained by a new electroweak penguin amplitude. Motivated by this result, we analyse the purely…
New physics contributions to the $Z$ penguin are revisited in the light of the recently-reported discrepancy of the direct CP violation in $K\to\pi\pi$. Interference effects between the standard model and new physics contributions to…