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Baryon Resonances in the 1/N_c Expansion

Richard F. Lebed
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Abstract

The 1/N_c expansion of QCD provides a valuable semiquantitative tool to study baryon scattering amplitudes and the short-lived baryon resonances embedded within them. A generalization of methods originally applied in chiral soliton models in the 1980's provides the key to deriving a rigorous 1/N_c expansion. One obtains model-independent relations among amplitudes that impose mass and width degeneracies among resonances of various quantum numbers. Phenomenological evidence confirms that patterns of resonant decay predicted by 1/N_c agree with data. One may extend the analysis to subleading orders in 1/N_c, where again agreement with data is evident, in both meson-baryon scattering and pion photoproduction.

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Richard F. Lebed. 2005-01-04. Baryon Resonances in the 1/N_c Expansion. https://doi.org/10.1142/9789812701725_0016

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