Higher Twist Distribution Amplitudes of the Nucleon in QCD

Abstract

We present the first systematic study of higher-twist light-cone distribution amplitudes of the nucleon in QCD. We find that the valence three-quark state is described at small transverse separations by eight independent distribution amplitudes. One of them is leading twist-3, three distributions are twist-4 and twist-5, respectively, and one is twist-6. A complete set of distribution amplitudes is constructed, which satisfies equations of motion and constraints that follow from conformal expansion. Nonperturbative input parameters are estimated from QCD sum rules.

Comments: 29 pages, 4 figures, eqn in (3.19) corrected, table 3 accordingly changed, some typos fixed