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arXiv · hep-ph/0301167

New Relations for Excited Baryons in Large N_c QCD

Thomas D. Cohen·Richard F. Lebed
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Abstract

We show that excited baryons in large N_c QCD form multiplets, within which masses are first split at O(1/N_c). The dominant couplings of resonances to various mesons are highly constrained: The N(1535) decays at leading 1/N_c order exclusively to eta-N rather than pi-N, and vice versa for the N(1650). This multiplet structure is reproduced by a simple large N_c quark model, well studied in the literature, that describes resonances as single-quark excitations.

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Thomas D. Cohen, Richard F. Lebed. 2003-01-24. New Relations for Excited Baryons in Large N_c QCD. https://doi.org/10.1103/physrevlett.91.012001

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