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arXiv · hep-ph/9412343

On the large-$N_c$ behavior of the $L_7$ coupling in $χ$PT

Santiago Peris·Eduardo de Rafael
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Abstract

It is shown that the usual large-$N_c$ counting of the coupling constant $L_{7}$ of the ${\cal O}(p^4)$ low-energy chiral $SU(3)$ Lagrangian \cite{GL85} is in conflict with general properties of QCD in the large-$N_c$ limit. The solution of this conflict within the framework of a chiral $U(3)$ Lagrangian is explained.

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Santiago Peris, Eduardo de Rafael. 1994-12-21. On the large-$N_c$ behavior of the $L_7$ coupling in $χ$PT. https://doi.org/10.1016/0370-2693(95)00160-m

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