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arXiv · hep-ph/0507267

Phenomenology of the Baryon Resonance 70-plet at Large N_c

Abstract

We examine the multiplet structure and decay channels of baryon resonances in the large N_c QCD generalization of the N_c = 3 SU(6) spin-flavor 70. We show that this ``70'', while a construct of large N_c quark models, actually consists of five model-independent irreducible spin-flavor multiplets in the large N_c limit. The preferred decay modes for these resonances fundamentally depend upon which of the five multiplets to which the resonance belongs. For example, there exists an SU(3) ``8'' of resonances that is eta-philic and pi-phobic, and an ``8'' that is the reverse. Moreover, resonances with a strong SU(3) ``1'' component prefer to decay via a K-bar rather than via a pi. Remarkably, available data appears to bear out these conclusions.

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BibTeXRIS

Thomas D. Cohen, Richard F. Lebed. 2005-07-22. Phenomenology of the Baryon Resonance 70-plet at Large N_c. https://doi.org/10.1103/physrevd.72.056001

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