相关论文: Eta-eta' mixing from V->Pgamma and J/psi->VP decay…

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.

The known ratio of the branching fractions for D_s^* --> D_s pi^0 and D_s^* --> D_s gamma may be used to extract the coupling of eta mesons to strange quarks once the value of the pi^0-eta mixing angle is known. This requires that realistic…

Both the mass spectra and the wave functions of the light pseudoscalar ($\pi,K,\eta,\eta'$) and vector($\rho,K^{*},\omega,\phi$) mesons are analyzed within the framework of the light-cone constituent quark model. A gaussian radial wave…

A phenomenological analysis on various decay processes is performed using an energy-dependent $\eta-\eta'$ mixing angle scheme. Special attention is given to the radiative couplings between lowest-lying vector and pseudoscalar mesons. The…

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…

We have performed a dynamical analysis of the mixing in the pseudoscalar channel with the goal of understanding the existence and behavior of the pseudoscalar glueball. Our philosophy has not been to predict precise values of the glueball…

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…

We analyze power-suppressed contributions to singlet pseudoscalar $\eta$ and $\eta^{\prime}$ meson transition form factors. These corrections stem from endpoint singularities and help improve the agreement between QCD theory and the…

In the quark-flavor mixing scheme, $\eta$ and $\eta'$ are linear combinations of flavor states $\eta_{q}=(u\bar{u}+d\bar{d})/\sqrt{2}$ and $\eta_{s}=s\bar{s}$ with the masses of $m_{qq}$ and $m_{ss}$, respectively. Phenomenologically,…

We compute power-suppressed corrections to the \eta\gamma and \eta^{\prime}\gamma transition form factors Q^2F_{\eta(\eta^{\prime})\gamma}(Q^2) arising from the end point regions x \to 0,1 by employing the infrared-renormalon approach. The…

In this work, we calculate radiative vertex $VP\gamma$ ($V=\phi,\omega,\rho$ and $P=\eta,\eta'$) by utilizing $\omega-\phi$ mixing scheme and taking into account the contributions of the three-particle twist-4 distribution amplitudes of the…

We discuss the effect of $\eta$--$\eta'$ mixing and of axial current anomalies on various decay processes. We describe the 2$\gamma$ decays of $\eta$ and $\eta'$, the radiative decays of low-lying vector mesons as well as the decays…

The electromagnetic transition form factors of $\eta$ and $\eta'$ are calculated in the light-cone perturbation theory. We show that it is unreliable to determine the \eta-\etap'$ mixing angle without any additional normalization conditions…

Within the framework of the effective Lagrangian approach, we perform a thorough analysis of the $J/\psi \to P\gamma(\gamma^*)$, $J/\psi \to VP$, $V\to P\gamma(\gamma^*)$, $P\to V\gamma(\gamma^*)$ and $P\to\gamma\gamma(\gamma^*)$ processes,…

It has been realized for a long time that knowing the \eta and \eta' wave functions in terms of quark and gluon components probes our understanding of non-perturbative QCD dynamics. Great effort has been given to this challenge -- yet no…

The two body decays of $B_d$ and $B_s$ decays into $J/\psi M$, where $M$ is a light meson, is studied under the very simple assumptions that the spectator quark does not play a role in the decay of the weak heavy quark or antiquark. This…

Involving of elastic rescattering and annihilation of quark-antiquark pairs in a final state allows us to explain a dependence of ratio for cross sections of $\eta'$ and $\eta$ mesons versus transfer momentum in charge exchange reactions.…

Using $e^+e^-$ annihilation data corresponding to an integrated luminosity of 3.19\,fb$^{-1}$ collected at a center-of-mass energy of 4.178~GeV with the BESIII detector, we measure the absolute branching fractions $\mathcal{B}_{D_s^+…

We calculate the shear (eta) and bulk (zeta) viscosities of a weakly coupled quark gluon plasma at the leading-log order with finite temperature T and quark chemical potential mu. We find that the shear viscosity to entropy density ratio…

U_A(1) symmetry breaking is studied by introducing the flavor mixing interaction proposed by Kobayashi, Maskawa and 't Hooft. Combining the one gluon exchange interaction, the rainbow like Schwinger-Dyson equation and the ladder like…