Large-Nc quark distributions in the delta and chiral logarithms in quark distributions of the nucleon

In a world with two quark flavors and a large number of colors (Nc), the polarized and unpolarized quark distributions in the delta are completely determined by those in the nucleon up to relative O(1/Nc2). In particular, we find qΔ(x)=[(1±2Tz)uN(x)+(1∓2Tz)dN(x)]/2(1+O(1/Nc2)) and ΔqΔ(x)=[(5±2Tz)ΔuN(x)+(5∓2Tz)ΔdN(x)]/10(1+O(1/Nc2)), where q=u,d and Tz the charge state of a delta. The result can be used to estimate the leading chiral-logarithmic corrections to the quark distributions in the nucleon.