Determination of the Parameters of Model Field Theories from Phase Shifts and Bound-States Energies

Abstract

The inversion problem is taken into account and solved in the framework of some models of quantum field theories. Both cases of one and multichannels models are considered. The conditions that must be satisfied by the phase shifts in order that they can be reproduced by the considered models are discussed and relations are derived among the scattering phase shifts, the energies of the bound states and the parameters of the models. It turns out that in certain cases the parameters are completely determined while in other cases some freedom is left.