相关论文: Electroweak penguin amplitudes and constraints on …

We study the effects of electroweak penguin (EWP) amplitudes in $B$ meson decays into two charmless pseudoscalars in the approximation of retaining only the dominant EWP operators $Q_9$ and $Q_{10}$. Using flavor SU(3) symmetry, we derive a…

We discuss the role of electroweak penguins in $B$ decays to two light pseudoscalar mesons. We confirm that the extraction of the weak phase $\alpha$ through the isospin analysis involving $B\to\pi\pi$ decays is largely unaffected by such…

Determinations of the CKM phase $\gamma$ from weak nonleptonic $B$ decays are affected by electroweak (EW) penguins and rescattering effects. In this talk it is explained how the EW penguin effects can be controlled with the help of SU(3)…

We calculate CP-violating rates and asymmetry parameters in charged and neutral $B\to \pi\pi, \pi K$ and $\bar K K$ decays arising from the interference of tree and penguin (strong and electroweak) amplitudes with different strong and CKM…

We present strategies for determining electroweak penguins from experimental data. Using the CKM-angle $\gamma$ as one of our central inputs and making some reasonable approximations, we show that the $\bar b\to\bar s$ electroweak penguin…

The role of penguin amplitudes in CP violating $B$ decays is reviewed, emphasizing recent progress in the analysis of electroweak penguin contributions. It is shown how these terms are included in a model-independent manner when measuring…

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…

We report recent results from the BABAR experiment on semileptonic charmless B-meson decays and electroweak penguin processes. Semileptonic charmless decays are used to determine |Vub| and the exclusive modes considered here also begin to…

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…

We derive constraints for $B\to VV$ modes ($V= vector meson) that allow aquantitative assessment of the contributions from electroweak penguins (EWP) and/or new physics. Interplay of direct CP with oscillation studies then leads to the…

We discuss a novel electromagnetic penguin contribution to the transverse helicity amplitudes in B decays to two vector mesons, which is enhanced by two powers of mB/Lambda relative to the standard penguin amplitudes. This leads to unique…

We show that the neglect of the $(V-A)\times (V+A)$ pieces of the electroweak penguin (EWP) amplitudes in the effective hamiltonian (the Wilson coefficients are very small) allows one to calculate the relative size of some tree and EWP…

The decays of $B$ mesons to a pair of charmless pseudoscalar ($P$) mesons are analyzed within a framework of flavor SU(3). Symmetry breaking is taken into account in tree ($T$) amplitudes through ratios of decay constants; exact SU(3) is…

Based on the most recent data in charmless B decays including the very recently reported large direct CP violations, it is shown that the weak phase gamma can well be extracted without two-fold ambiguity even only from two decay modes…

Current data of charmless B meson decays to two pseudoscalar mesons (PP) and one vector and one pseudoscalar mesons (VP) are analyzed within the framework of flavor SU(3) symmetry, a working principle that we have tested by allowing…

The recently observed $B^-\to K^- \pi^0$, $\bar K^0 \pi^-$ and $\bar B^0 \to K^- \pi^+$ decay modes appear to have nearly equal branching ratios. This suggests that tree and electroweak penguins play an important role, and inclusion of the…

We comment on a recent suggestion for measuring $\gamma$ in $B^0(t)\to K_S\pi^+\pi^-$. A difficulty is pointed out in relating electroweak penguin and tree amplitudes in $B^+\to K^0\pi^+\pi^0$, which is crucial for an implementation of this…

The decays of $B$ mesons to charmless final states consisting of a vector meson ($V$) and a pseudoscalar meson ($P$) are analyzed within flavor SU(3). Predictions are compared with new data from the CLEO Collaboration. Dominant…

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…

The ratio of partial decay rates for charged and neutral $B$ mesons to $K \pi$ final states provides information on the weak phase $\gamma \equiv {\rm Arg} (V_{ub}^*)$ when augmented with information on the CP-violating asymmetry in the…