Hadronic correlation functions in the interacting instanton liquid

In this paper we study hadronic correlation functions in the interacting instanton liquid model, both at zero and nonzero temperature T. At zero T we investigate the dependence of the correlators on the instanton ensemble, in particular, the effect of the fermionic determinant. We demonstrate that quark-induced correlations between instantons are important, especially in the repulsive η^' and δ-meson channels. We also calculate a large number of mesonic and baryonic correlation functions as a function of temperature. We find three different types of behavior as T→Tc. The vector channels ρ, a₁, Δ show a gradual melting of the resonance contribution and approach free quark behavior near the chiral phase transition. The light pseudoscalars and scalars π, σ as well as the nucleon show stable resonance contributions, probably even surviving above Tc. Correlation functions in the heavy scalar channels η^', δ are enhanced as T→Tc.