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arXiv · hep-ph/9605267

Chiral Perturbation Theory, Large-N_c and the eta' Mass

N. Evans·S. D. H. Hsu·M. Schwetz
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Abstract

Using chiral perturbation theory and the large-$N_c$ expansion, we obtain expressions for the $η'$ mass and $η- η'$ mixing in terms of low-energy chiral Lagrangian parameters. This is accomplished through an intermediate step of `matching' the topological susceptibility in the large-$N_c$ and chiral Lagrangian descriptions. By inserting the values of well-measured parameters we obtain predictions involving the the second order parameters $L_6,L_7$ and $L_8$. The prediction for $L_6$ is quite restrictive even after allowing for $1/ N_c$ corrections.

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N. Evans, S. D. H. Hsu, M. Schwetz. 1996-05-09. Chiral Perturbation Theory, Large-N_c and the eta' Mass. https://doi.org/10.1016/0370-2693(96)00663-6

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