INTERPOLATION BETWEEN THE LOW-ENERGY AND THE HIGH-ENERGY BEHAVIOR OF HADRONIC CURRENT CORRELATION-FUNCTIONS

We consider the results for hadronic current correlators that we have obtained previously using a generalized Nambu-Jona-Lasinio (NJL) model . Given the nature of the NJL model, these results are expected to be valid for energies and momenta below some cutoff of about 1 Gev. Howev er, the very high-energy behavior of such correlators can be calculate d in perturbation theory. In this work, we use dispersion relations to interpolate between the known high-energy behavior of the correlators and the low-energy behavior that was obtained from the NJL model. The results of calculations made using the NJL model serve to fix various substraction constants in these dispersion relations. In this manner we obtain continuous curves for the correlation functions for all mome nta. This procedure is defined such that the (low-energy) predictions of the NJL model are unchanged and such that the correlators have the correct high-energy behavior. In addition to the various results prese nted in terms of momentum-space variables, we also calculate the scala r-isoscalar correlation function in coordinate space. (C) 1995 Academi c Press, Inc.