Baryon resonances at large Nc, or Quark Nuclear Physics

Abstract

We suggest a new point of view according to which baryon resonances can be understood as collective excitations about intrinsic one-quark excitations in a mean field of definite symmetry. This approach is justified in the limit of large number of colours Nc, and is similar to the physics of large-A nuclei, hence "quark nuclear physics". Although in the real world Nc is only three, we obtain a good agreement with the observed resonance spectrum of light baryons up to 2 GeV, and of lowest charmed baryon multiplets. A by-product of the scheme is the prediction of new exotic charmed (and bottom) baryons that may be stable against strong decays.

Invited talk at the Sixth International Conference on Quarks and Nuclear Physics, April 16-20, 2012, Ecole Polytechnique, Palaiseau, Paris, France, to be published in the Proceedings