Hadronic Correlation Functions in the Interacting Instanton Liquid
Abstract
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→
T
c
. The vector channels
ρ,
a
1
,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
T
c
. Correlation functions in the heavy scalar channels
η
′
,δ
are enhanced as
T→
T
c
.