The F/D Ratios of Spin-Flip Baryon Vertex in 1/Nc Expansion

Abstract

We calculate the F/D ratios of spin 1/2 baryon vertex for both the non-relativistic quark model and the chiral soliton model with arbitrary number of color degrees of freedom Nc and examine the results in terms of the consistency condition approach for the baryon vertices recently developed by Dashen, Jenkins and Manohar from the viewpoint of QCD. We show that the 1/Nc corrections have two different origins, i.e., one is from the baryon states or baryon wave functions and the other from the vertex operators. Although in the limit Nc →∞ the F/D tends to 1/3 in all models, the 1/Nc expansion of F/D ratio does not converge for Nc = 3 in the chiral soliton model in contrast to the non-relativistic quark model.