相关论文: New Dipole Penguin Contribution to K --> pi pi dec…

The phenomenon of CP violation in the B system and strategies for extracting CKM phases are reviewed. We focus both on general aspects and on some recent developments including CP-violating asymmetries in B_d decays, the B_s system in light…

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…

We study the axial amplitudes for the N-Delta transition in models with quarks and chiral mesons. A set of constraints on the pion field is imposed which enforces PCAC and the off-diagonal Goldberger-Treiman relation. The quark contribution…

We present a new analysis of the ratio epsilon'/epsilon which measures the direct CP violation in K\to\pi\pi decays. We use the 1/N_c expansion within the framework of the effective chiral lagrangian for pseudoscalar mesons. From general…

We study in next-to-leading order QCD hadronic penguin $B$ decays in the Standard and two-Higgs-doublet models. Although the gluonic penguin dominates, we find the electroweak contribution non-negligible. In the Standard Model, the…

Motivated by the recent measurements of CP violating effects in singly Cabibbo suppressed $D^0$ decays, we revisit the theoretical predictions of these channels. Using up-to-date values for the decay constants and form factors, we find…

We present measurements on penguin dominated B decays which are sensitive to new physics, such as CP-violation parameters and branching fractions in $b \to s q\bar{q}$ and $b \to d q\bar{q}$ gluonic and radiative decays using a large sample…

The Weinberg operator (chromo-electric dipole moment of gluon) is a CP violating quantity generated in many candidates of new physics beyond the standard model, and it contributes to observables such as the electric dipole moments (EDM) of…

Using the QCD factorization approach, we reexamine the two-body hadronic charmless $B$-meson decays to final states involving a pseudoscalar~($P$) and a vector~($V$) meson, with inclusion of the penguin contractions of spectator-scattering…

We present an {\it algebraic} isospin approach towards a more straightforward and model-independent determination of the weak phase $\alpha$ (or $\phi_2$) and QCD penguin pollution in $B\to \pi\pi$ decays. The world averages of current…

We discuss about a possibility of large electro-weak penguin contribution in B -> K pi from recent experimental data. The several relations among the branching ratios which realize when the contributions from tree type and electro-weak…

The 2.5 sigma discrepancy between theory and experiment observed in the difference Delta ACP = ACP(B- --> pi0 K-) - ACP(Bb0 --> pi+ K-) can be explained by a new electroweak (EW) penguin amplitude. Motivated by this result, we have analyzed…

We analyze the rare decay mode $B \to \phi \pi $, which is a pure penguin induced process, receiving dominant contribution from the electroweak penguins. Thus the standard model branching ratio is expected to be very small, which makes it…

Motivated by diquark exchange, we construct a class of extensions of the standard model. These models can generate large CP conserving and CP violating contributions to the doubly Cabbibo suppressed decays D^0\to K^+\pi^- without affecting…

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…

For about twenty years, $B\to\pi K$ decays are in the focus of $B$-decay studies. We show that a correlation between the CP asymmetries of $B^0_d\to\pi^0K_{\rm S}$ reveals a tension with the Standard Model. Should it be due to New Physics,…

Penguin contributions, being not negligible in general, can hide the information on the CKM angle alpha coming from the measurement of the time-dependent B0(t) -> pi+pi- CP-asymmetry. Nevertheless, we show that this information can be…

Hadronic tau decay data provides access to the light quark vector (V) and axial vector (A) spectral functions. This makes possible investigations of the dynamics of QCD at intermediate scales and improved determinations of certain…

The experimental value for the isospin amplitude Re(A_2) in K->pi pi decays has been successfully explained within the Standard Model, both within large N approach to QCD and by QCD lattice calculations. On the other hand in both approaches…

The difference between the CP asymmetries of the $B^0 \to K^+ \pi^-$ and $B^+ \to K^+ \pi^0$ decays has been recently confirmed with an evidence larger than $5\sigma$'s. We discuss it as a possible signal of new physics associated with new…