We study excited baryon decay widths in large Nc QCD. It was suggested previously that some spin-flavor mixed-symmetric baryon states have strong couplings of O(Nc-1/2) to nucleons [implying narrow widths of O(1/Nc)], as opposed to the generic expectation based on Witten's counting rules of an O(Nc0) coupling. The calculation obtaining these narrow widths was performed in the context of a simple quark-shell model. This paper addresses the question of whether the existence of such narrow states is a general property of large Nc QCD. We show that a general large Nc QCD analysis does not predict such narrow states; rather they are a consequence of the extreme simplicity of the quark model.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)