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arXiv · 1612.05473

$\eta$-$\eta'$ Mixing in Large-$N_c$ Chiral Perturbation Theory

P. Bickert·P. Masjuan·S. Scherer
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Abstract

We present a calculation of the $\eta$-$\eta'$ mixing in the framework of large-$N_c$ chiral perturbation theory. A general expression for the $\eta$-$\eta'$ mixing at next-to-next-to-leading order (NNLO) is derived, including higher-derivative terms up to fourth order in the four momentum, kinetic and mass terms. In addition, the axial-vector decay constants of the $\eta$-$\eta'$ system are determined at NNLO. The numerical analysis of the results is performed successively at LO, NLO, and NNLO. We investigate the influence of one-loop corrections, OZI-rule-violating parameters, and $\mathcal{O}(N_c p^6)$ contact terms.

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P. Bickert, P. Masjuan, S. Scherer. 2016-12-16. $\eta$-$\eta'$ Mixing in Large-$N_c$ Chiral Perturbation Theory. https://doi.org/10.1103/physrevd.95.054023

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