The Study Of The Radiative Vertex VPγ And η-η'Mixing Scheme

In this work, we calculate radiative vertex VPy, (V=φ,ω,ρ; P=η,η′) by utilizingω-φmixing scheme and taking into the contributions of the three-particle twist-4 distribution amplitudes of the photon in QCD sum rules on light cone. According to experimental data of V→Pyγand P→Vγfrom PDG, a value of theη-η′mixing angle,,is extracted in the framework of the quark-flavor basis to describe the,η-η′system, (ψis the mixing angle.The results shows:whenψ= 40.9±0.5, the theoretical electromagnetic coupling constant g(?) using the QCD sum rules can fit the experimental g(?) extracted from PDG Date. At the same time, in the decayφ→ηγorφ→η′γ, the decay width ratio R(?)= 4.92×10-3 is slightly smaller than the Rφ= 4.77×10-3 with the KLOE experimental group. One possible reason is that we adopt the mixing scheme of the pseudoscalar mesonsη-η′without considering the gluon ball ingredients.Therefore, the further study is to add the gluon ball constituents contribution in the mixing scheme ofη-η′. In order to get sensitive the theoretical results, we must discuss the leading contribution of the gluon ball, and calculate the QCD one-loop correction of the qq constituents. In this paper, we have finished the QCD radiative correction of the photon twist-2 distribution amplitude, the next work will be completed in the futurer.