相关论文: Strong Anomalies in Kaon Decays
Inclusive cross section for pion production in proton - proton collisions are calculated based on unintegrated parton distribution functions (uPDFs). In addition to purely gluonic terms the present approach includes also quark degrees of…
We present results for the spectrum of light and strange mesons on configurations with two flavors of mass-degenerate Chirally Improved sea quarks. The calculations are performed on seven ensembles of lattice size 16^3x32 at three different…
QCD corrections are evaluated to FCNC processes like $B \to X_s \nu \bar{\nu}$, $K \to \pi \nu \bar{\nu}$, $B \to l^+ l^-$ or $K_L \to \mu^+ \mu^-$, i.e. to processes mediated by effective operators containing neutrino currents or axial…
The regularities at large distances of complete gauge invariance in QCD are shown to bear nontrivial consequences for the selection among inequivalent representations of canonical commutation (anticommutation) rules for gauge boson (quark)…
Parity violation in QCD is a consequence of the so-called QCD $\theta$-vacuum. As a result, parity-odd fragmentation functions are introduced and they bring in new observables in the back-to-back dihadron productions in…
In this work, we studied the quasi-two-body decays $B_{(s)} \to \psi [K^*(892), K^*(1410),$ $K^*(1680)] \to \psi K\pi$ by employing the perturbative QCD (PQCD) factorization approach, where the charmonia $\psi$ represents $J/\psi$ and…
We discuss top quark production and its subsequent decay at lepton colliders including both QCD corrections and anomalous gamma / Z - t t-bar couplings. The off-diagonal spin basis for the top and anti-top quarks is shown to be useful to…
We investigate the role of exclusive channels in semi-inclusive electroproduction of pions and kaons. Using the QCD factorization theorem for hard exclusive processes we evaluate the cross sections for exclusive pseudoscalar and vector…
The chiral anomaly is a fundamental property of quantum chromodynamics (QCD). It governs the transition amplitudes for processes involving an odd number of Goldstone bosons of chiral symmetry breaking. In case of the coupling of three pions…
The leading short-distance contributions to hadronic hard-scattering cross sections in the operator product expansion are described by twist-two quark and gluon operators. The anomalous dimensions of these operators determine the splitting…
We consider the dependence of the pion and kaon decay constants on the up, down and strange quark masses in QCD with strict isospin symmetry. The role of dynamical vector meson degrees of freedom is scrutinized in terms of an effective…
The quantities $\epsilon_K^\prime$ and $\epsilon_K$ measure the amount of direct and indirect CP violation in $K\to \pi\pi$ decays, respectively. Using the recent lattice results from the RBC and UKQCD Collaborations and a new compact…
We quantify the important effect of strong final state interactions in the weak $K\to 2\pi$ amplitudes, using the measured $\pi$-$\pi$ phase shifts with J=0 and $I=0,2$. The main results of this analysis, with their implications for…
A calculation of the semi--leptonic decays of the kaon ($K_{l3}$) is presented. The results are direct predictions of a covariant model of the pion and kaon introduced earlier by Ito, Buck, Gross. The weak form factors for $K_{l3}$ are…
Domain model of QCD allows for description of wide range of meson observables, dynamical chiral symmetry breaking, and resolution of $U_A(1)$ and strong $CP$ problems. The purpose of the present study is transition form-factor of neutral…
The decays and mixing of $K$ mesons are remarkably sensitive to the weak interactions of quarks and leptons at high energies. They provide important tests of the standard model at both first and second order in the Fermi constant $G_F$ and…
We provide a snapshot of recent progress in hadron physics made using QCD's Dyson-Schwinger equations, reviewing the generation of a quark anomalous chromomagnetic moment, which may explain the longstanding puzzle of the $a_1$-$\rho$ mass…
A lattice QCD approach to the calculation of the long-distance contributions to $\epsilon_K$ is presented. This parameter describes indirect CP violation in $K\to\pi\pi$ decay. While the short-distance contribution to $\epsilon_K$ can be…
We give an overview of recent developments in the computation of the anomalous dimension matrix of composite operators in non-forward kinematics. The elements of this matrix set the evolution of non-perturbative parton distributions such as…
The anomalous dimension $\gamma_m =1$ in the infrared region near conformal edge in the broken phase of the large $N_f$ QCD has been shown by the ladder Schwinger-Dyson equation and also by the lattice simulation for $N_f=8$ for $ N_c=3$.…