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arXiv · hep-ph/0411292

Eta-eta' masses and mixing: a large N_c reappraisal

J. -M. Gerard·E. Kou
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Abstract

We reconcile the 1/N_c expansion with the observed eta-eta' mass spectrum. The chiral corrections introduced for that purpose are natural and consistent with the octet-singlet mixing angle theta=-(22\pm 1)^{\circ} extracted from phenomenology in the large N_c limit.

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J. -M. Gerard, E. Kou. 2005-01-24. Eta-eta' masses and mixing: a large N_c reappraisal. https://doi.org/10.1016/j.physletb.2005.04.057

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