Related papers: Large electroweak penguin contribution in B -> K p…
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…
The complex phases $\phi_d$ and $\phi_s$, associated with the mixing between neutral $B_q^0$ and $\bar B_q^0$ mesons ($q\in\{d,s\}$), are key observables to test the Standard Model and search for contributions from new physics. They are…
We study Lambda_{QCD}/m_B corrections to factorization in B -> K pi decays. First, we analyze these decay channels within factorization, showing that, irrespectively of the value of gamma, it is not possible to reproduce the experimental…
Full expressions of the $B^0_d \to \pi^+ \pi^-$ and $B^0_d \to \pi^0 \pi^0$ amplitudes, given in terms of matrix elements of operators of the effective weak Hamiltonian, are used to study the dependence of the relevant branching ratios on…
The decay B -> J/Psi K_S remains the most important source of information for the B_d mixing phase, determined by the CKM angle beta in the standard model. When aiming at a precision appropriate for present and coming high luminosity…
In the heavy-quark limit, the hadronic matrix elements entering nonleptonic $B$-meson decays into two light mesons can be calculated from first principles including ``nonfactorizable'' strong-interaction corrections. The $B\to\pi K,\pi\pi$…
We reanalyze the decay $B_d\to\pi^+\pi^-$ without assuming dominance of QCD penguins with internal top-quark exchanges. In that case the weak phase of the $\bar b \to\bar d$ QCD penguin amplitude is not related in a simple way to the CKM…
CP-violating asymmetries in the decay $B^0(t)\to \pi^+ \pi^-$ are a potentially rich source of information about both strong and weak phases. In a previous treatment by the present authors use was made of an assumption about the relative…
The unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix has been well established by both direct and indirect measurements without any evidence of discrepancy. The CKM weak phase $\alpha$ is directly measured using an isospin analysis…
We study the effect from a sequential fourth generation quark on penguin-dominated two-body nonleptonic B meson decays in the next-to-leading order perturbative QCD formalism. With an enhancement of the color-suppressed tree amplitude and…
Time-dependence in $B^0(t) \to \pi^+ \pi^-$ and $\ob(t) \to \pi^+ \pi^-$ is utilized to obtain a maximal set of information on strong and weak phases. One can thereby check theoretical predictions of a small strong phase $\delta$ between…
The penguin loop-suppressed $B\to\phi K$ decays are highly sensitive to contributions of hypothetical heavy new particles. Particularly interesting probes for testing the Standard Model and revealing such phenomena are provided by CP…
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…
Recent measurements of the time-dependent CP asymmetry of the B -> phi K_S decay give results whose central values differ from standard model expectations. It is shown how such data can be used to identify new physics contributions in a…
Radiative penguin decays provide an indirect probe for physics beyond the Standard Model and contribute to the determination of the CKM matrix elements. Copious quantities of B mesons produced at the B-Factories permit precision…
We discuss what we can understand from $\phi_1$ and $B^0_d\to \pi^+ \pi^- $ decay mode. Using a convention without weak phases $\phi_2$ and $\phi_3$, we can solve the parameters from the time-depended CP asymmetry. If we can put a condition…
We present the measurement, performed by the BABAR Collaboration, of the weak phase alpha from the time dependent CP asymmetries in B0--> a_1(1260)+- pi-+ decays. The model error induced by penguin contributions to the B0 --> a_1(1260)+-…
We study the penguin over tree ratio in $D\rightarrow \pi\pi$ decays. This ratio can serve as a probe for rescattering effects. Assuming the Standard Model and in the isospin limit, we derive expressions that relate both the magnitude and…
We analyze the effects of the space-like penguin diagrams in two body B decays $B^-\to K^-{\bar K}^0$ and $B^-\to \pi^-{\bar K}^0$. Special attention is paid to the operator $Q_6$, whose contribution is large in the BSW model, but vanishes…
We propose a set of new optimized observables using penguin mediated $\bar{B}_d$ and $\bar{B}_s$ decays: ${\bar B}_{d,s} \to K^{*0} \bar{K}^{*0}$, ${\bar B}_{d,s} \to K^{0} \bar{K}^{0}$, ${\bar B}_{d,s} \to K^{0} \bar{K}^{*0}$ and ${\bar…