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Comments on the large Nc behavior of light scalars

J. R. Pelaez
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Abstract

I review the large Nc behavior of light resonances generated from unitarized one-loop Chiral Perturbation Theory. In contrast with the rho or K*, the scalar behavior is at odds with a qqbar "dominant component". In fact, in the light scalar region, meson-meson amplitudes vanish as Nc increases. Also, the scalar widths, obtained from their associated poles, behave as O(Nc^{1/2})<Gamma<O(Nc). We also clarify on the physical relevance of considering large Nc not too far from real life, Nc=3, and the interpretation of the mathematical Nc=infinity limit.

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J. R. Pelaez. 2005-09-26. Comments on the large Nc behavior of light scalars. https://arxiv.org/abs/hep-ph/0509284

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