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arXiv · hep-ph/0310237

Large N_c behavior of light resonances in meson-meson scattering

J. R. Pelaez
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Abstract

By scaling the parameters of meson-meson unitarized Chiral Perturbation Theory amplitudes according to the QCD large N_c rules, one can study the spectroscopic nature of light meson resonances. The scalars sigma, kappa f_0(980) and, possibly, the a_0(980) do not seem to behave as q-qbar states, in contrast to the vectors rho(770) and K*(892). The behavior shown by the scalars is naturally explained in terms of diagrams with intermediate $\bar q\bar q qq$-like states. Here we review our recent study and show how the results do not depend on the different fits to data.

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J. R. Pelaez. 2003-10-20. Large N_c behavior of light resonances in meson-meson scattering. https://doi.org/10.1063/1.1799683

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