Chiral Divergent Properties of Hadrons in the Large-N_c Limit

Abstract

We compute the leading non-analytic correction to the baryon mass in the combined limits m_\pi -> 0, N_c -> \infty with the product m_\pi x N_c held fixed. We reproduce the results of Cohen and Broniowski using semiclassical methods rather than heavy-baryon chiral perturbation theory. The calculation is organized to demonstrate: (1) the model independence of our results; and (2) the crucial role played by (iso)rotations of the hedgehog pion cloud surrounding the baryon. Our rotationally improved large-N_c calculation yields results that naturally interpolate between ordinary chiral perturbation theory on the one hand, and large-N_c physics on the other.