相关论文: Unfactorizing Polychromatic Penguins

The NLO contributions to some two-body charmless hadronic B meson decays, such as those from the QCD vertex corrections, the quark loops and the chromo-magnetic penguins, have been calculated in the pQCD factorization approach.

We complete the calculation of the QCD penguin amplitude at next-to-next-to-leading order in the QCD factorization approach to non-leptonic B-meson decays. This provides the last missing piece in the computation of the QCD correction to…

A major problem in the determination of the the CP angle $\alpha$, that should be measured through modes of the type $B_d, \bar{B}_d \to \pi \pi , \cdots ,$ is the uncertainty coming from Penguin diagrams. We consider the different ground…

We compute the effective hamiltonian for non-leptonic |Delta F| = 1 decays in the standard model including next-to-next-to-leading order QCD corrections. In particular, we present the complete three-loop anomalous dimension matrix…

We present results on the NLO (alpha_s^2) spectator-scattering corrections to the topological penguin amplitudes for charmless hadronic two-body B-decays in QCD factorization. The corrections can be sizable for the colour-suppressed…

Isospin-breaking effects, in particular those associated with electroweak-penguin contributions and pi0-eta,eta' mixing, have long been known to affect the Standard Model prediction of Re(epsilon'/epsilon) in a significant manner. We have…

We compute branching ratios of $B\to K\pi$ decays in the framework of perturbative QCD factorization theorem. Decay amplitudes are classified into the topologies of tree, penguin and annihilation, all of which contain both factorizable and…

We calculate the O(alpha_s) corrections to the Z^0-penguin and electroweak box diagrams relevant for non-leptonic Delta F = 1 decays with F = S, B. This calculation provides the complete O(alpha_w alpha_s) and O(alpha_w alpha_s sin^2…

Nonfactorizable effects in hadronic charmless B -> PP, VP decays can be parametrized in terms of the effective number of colors N_c in the effective parameters $a_i^{eff}$ that are linear combinations of Wilson coefficients. It is shown…

The precision of the CP phases $2\beta$ and $2\beta_s$ determined from the mixing-induced CP asymmetries in $B_d\to J/\psi K_S$ and $B_s\to J/\psi \phi$, respectively, is limited by the unknown long-distance contribution of a penguin…

We revisit the Next-to-Leading Order (two-loop) contributions to the Anomalous Dimensions of $\Delta F = 1$ four-quark operators in QCD. We devise a test for anomalous dimensions, that we regard as of general interest, and by means of which…

Recently, we pointed out that chiral transformation properties of strong penguin operators change in the transition from unquenched to (partially) quenched QCD. As a consequence, new penguin-like operators appear in the (partially) quenched…

Branching fractions and CP-violating asymmetries of charmless $\bar B_s\to PP, VP, VV$ decays (P and V denoting pseudoscalar and vector mesons, respectively) are re-examined in the framework of QCD factorization (QCDF). We take into account…

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 the analysis of \epsilon^\prime/\epsilon it has been traditional to consider the isospin-breaking effects arising from electroweak-penguin contributions and from \pi^0-\eta and \pi^0-\eta^\prime mixing, yet additional isospin-violating…

This thesis presents the setup and results of numerical calculation of hadronic matrix elements of Delta S=1 weak operators, with the aim of studying the Delta I=1/2 rule and direct CP violation. Such study provides a useful comparison of…

The nonperturbative content of the QCD vacuum permits the occurrence of QCD-vaccum condensate contributions to penguin amplitudes. We calculate the dimension-4 $<m_q\bar qq>$ and $<\alpha_s G^2>$ contributions to the effective Wilson…

QCD penguins are responsible for about 2/3 of the Delta I=1/2 rule in K to pi pi decays, as inferred from a combined analysis of K to pi pi and KL to gamma gamma. Further tests based on the decays KS to pi0 gamma gamma and K+ to pi+ gamma…

The mixing-induced CP asymmetries in $B_d \to J/\psi K_S$ and $B_s \to J/\psi \phi$ are essential to detect or constrain new physics in the $B_d\! - \overline{\!B}{}_d$ and $B_s\! - \overline{\!B}{}_s$ mixing amplitudes, respectively. To…

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 $B\to\pi K,\pi\pi$…