Analysis of baryon properties in large-Nc chiral perturbation theory

Abstract

We discuss how to compute corrections to one-loop order to the baryon axial-vector current and magnetic moments in heavy baryon chiral perturbation theory in the large-Nc limit, where Nc is the number of colors. Loop graphs with octet and decuplet intermediate states cancel to various orders in Nc as a consequence of the large-Nc spin-flavor symmetry of QCD baryons. These cancellations are explicitly shown for the general case of Nf flavors of light quarks. We also indicate how to compare our resultant expressions with the corresponding ones obtained within conventional heavy baryon chiral perturbation theory at the physical values Nc = 3, Nf = 3. We observe an excellent agreement order by order.