Scattering processes in the massive Schwinger model

We derive the (matrix-valued) Feynman rules of the mass perturbation theory and use it for the resummation of the n-point functions with the help of the Dyson-Schwinger equations. We use these results for a short review of the resulting spectrum of the model and for a discussion of scattering processes. We find that in scattering cross sections all the corresponding resonances and higher particle production thresholds of the model are properly taken into account by our resummed mass perturbation theory, without the need of further approximations. copyright 1997 The American Physical Society