Evolution Effects on the Nucleon Distribution Amplitude

We study the Brodsky-Lepage evolution equation for the nucleon and construct an eigenfunction basis by including contributions of up to polynomial order $9$. By exployting the permutation symmetry $P_{13}$ of these eigenfunctions, a basis of symmetrized Appell polynomials can be constructed in which the diagonalization of the evolution kernel is considerably simplified. The anomalous dimensions are calculated and found to follow a power-law behavior. As an application, we consider the Brodsky-Huang-Lepage ansatz. An algorithm is developed to properly incorporate such higher order contributions in a systematic way.