相关论文: On the $\eta'$ Gluonic Admixture

The radiative decays $\eta'(\eta)\rta\gamma\gamma$ are discussed. The modifications of the conventional PCAC formulae due to the gluonic contribution to the flavour singlet axial anomaly are given. The decay constants satisfy a modified…

We investigate whether known properties of the $\eta'$ meson are consistent with its being the Goldstone boson of the spontaneously broken anomaly-free R symmetry required in the light gluino scenario. We fit the masses and $2\gamma$ decays…

Intriguing B --> K eta' decays provide a unique opportunity to study a joining of two-gluon configurations arising from the penguin b --> sG and b --> sGG transitions, with those inherent to the eta' particle. We employ the heavy-light…

We calculate the flavor-singlet contribution to the $B\to\eta^{(\prime)}$ transition form factors from the gluonic content of the $\eta^{(\prime)}$ meson in the large-recoil region using the perturbative QCD approach. The formulation for…

Using the recently proposed $gg --> eta'$ effective vertex, we investigate the production of $\eta'$ from gluon fusion in $pA$ collisions. We show that measuring $\eta'$ production cross-section at moderate $x_{\eta'}$ yields direct…

We present results for the $\eta$ and $\eta^\prime$ masses and their four independent decay constants at the physical point as well as their anomalous gluonic matrix elements $a_{\eta^{(\prime)}}$. The chiral and continuum limit…

For hadronic two-body decays of charmed mesons involving $\eta$ or $\eta'$, resonance-induced final-state interactions (FSI) that mimic the W-exchange or the W-annihilation topology can play an essential role. In particular, the decays…

We discuss the role of gluon dynamics in $\eta'$ physics and in nucleon resonances where excitations of gluonic potentials may also be important. Interesting phenomenology includes a possible narrow near threshold resonance in $\eta'$…

We point out that the recent Belle measurements of the $B_{d/s} \to J/\Psi \eta^{(')}$ decays imply large pseudoscalar glueball contents in the $\eta^{(\prime)}$ meson. These decays are studied in the perturbative QCD (PQCD) approach,…

It is reported on a leading-twist analysis of the eta - photon and eta' - photon transition form factors. The analysis allows for an estimate of the lowest Gegenbauer coefficients of the quark and gluon distribution amplitudes.

We study the mixing of the scalar glueball into the isosinglet mesons $f_0 (1370)$, $f_0(1500)$, and $f_0(1710)$ to describe the two-body decays to pseudoscalars. We use an effective Hamiltonian and employ the two-angle mixing scheme for…

We compute the contribution of the gluonic component of the energy-momentum tensor (EMT) to the angular momentum density in various decompositions. We use the light-front Hamiltonian technique, and a two-component formalism in light-front…

The QCD gauge field is modeled as an ensemble of statistically independent selfdual and antiselfdual regions. This model is motivated from instanton physics. The scale anomaly then allows to relate the topological susceptibility to the…

The confinement mechanism earlier proposed by author is applied to describe the (possible) ground state of toponium $\eta_t$. For this aim the nonperturbative consistent approach is elaborated in both relativistic and nonrelativistic cases.…

We address the problem of observed charmonium decays which should be forbidden in perturbative QCD. We examine the model in which these decays proceed through a gluonic component of the $J/\Psi$ and the $\eta_c$, arising from a mixing of…

Based on the branching fractions of J/psi(psi(2S))-> VP from different collaborations, the pseudoscalar mixing is extensively discussed with a well established phenomenological model. The mixing angle is determined to be -14 degree by…

It is shown that the study of the $\omega-\rho^0$ interference pattern in the $J/\psi\to (\rho^0+\omega)\eta\to\pi^+\pi^-\eta$ decay provides the evidence for the large (nearly $90^\circ$) relative phase between the one-photon and the…

We critically reexamine the formalism for treating the leading-twist contributions from the two-gluon Fock components occurring in hard processes that involve eta and eta' mesons and establish a consistent set of conventions for the…

We present a detailed study of the exclusive radiative decays $Z\to\eta^{(\prime)}\gamma$ employing the QCD factorization approach. We derive a factorization formula for the decay amplitudes valid at leading power in an expansion in…

I briefly review the formalism for treating the leading-twist two-gluon states appearing in processes which involve eta and eta' mesons. The constraints on the size of the lowest order Gegenbauer coefficients of the two-gluon distribution…