BARYONIC CORRELATORS IN THE RANDOM INSTANTON VACUUM

This is the third paper of a series devoted to a systematic study of QCD correlation functions in the framework of an instanton model for the QCD vacuum. In this paper we concentrate on the quark-quark (diquark) and three quark (baryon) channels. We have found that the quark-quark interaction resembles the one between quarks and antiquarks. Similar to the pion and rho channels, the interaction in the scalar isospin I = 0 and vector I = 1 diquark channels is completely different: the former has a much stronger attractive interaction. As a consequence, the SU(3) octet (nucleon) and decuplet (delta) correlators are also found to be qualitatively different. Using a complete set of all available correlation functions, we determine masses and coupling constants for the nucleon and delta. Our results agree surprisingly well with the first lattice data on point to point correlators.