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arXiv · hep-ph/0512064

eta and eta' mesons and dimension 2 gluon condensate

D. Kekez·D. Klabucar
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Abstract

The study of light pseudoscalar quark-antiquark bound states in the Dyson-Schwinger approach with the effective QCD coupling enhanced by the interplay of the dimension 2 gluon condensate and dimension 4 gluon condensate , is extended to the eta-eta' complex. We include the effects of the gluon axial anomaly into the Dyson-Schwinger approach to mesons. The calculated masses, mixing and two-photon decay widths of eta and eta' mesons are in agreement with experiment. Also, in a model-independent way, we give the modification of the Gell-Mann--Okubo and Schwinger nonet relations due to the interplay of the gluon anomaly and SU(3) flavor symmetry breaking.

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D. Kekez, D. Klabucar. 2005-12-05. eta and eta' mesons and dimension 2 gluon condensate. https://doi.org/10.1103/physrevd.73.036002

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