A global fit to determine the pseudoscalar mixing angle and the gluonium content of the eta' meson
(Citations: 1)
F. Ambrosino, A. Antonelli, M. Antonelli, F. Archilli, P. Beltrame, G. Bencivenni, S. Bertolucci, C. Bloise, S. Bocchetta, F. Bossi, P. Branchini, G. Caponhttp://academic.research.microsoft.com/io.ashx?type=5&id=27724039&selfId1=0&selfId2=0&maxNumber=12&query=
We update the values of the eta-eta' mixing angle and of the eta' gluonium content by fitting our measurement Rphi = BR(phi --> eta'gamma)/BR(phi --> etagamma) together with several vector meson radiative decays to pseudoscalars (V --> Pgamma), pseudoscalar mesons radiative decays to vectors (P --> Vgamma) and the eta' --> gammagamma, pi0 --> gammagamma widths. From the fit we extract a gluonium fraction of ZG2 = 0.12±0.04, the pseudoscalar mixing angle psiP = (40.4±0.6)° and the phi-omega mixing angle psiV = (3.32±0.09)°. ZG2 and psiP are fairly consistent with those previously published. We also evaluate the impact on the eta' gluonium content determination of future experimental improvements of the eta' branching ratios and decay width.