New relations for excited baryons in large-N(c) QCD.
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.
Cohen
Thomas D
TD
Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA. cohen@physics.umd.edu
Lebed
Richard F
RF