Mass spectrum and elastic scattering in the massive SU(2)f Schwinger model on the lattice Original Research Article

We calculate numerically scattering phases for elastic meson-meson scattering processes in the strongly coupled massive Schwinger model with an SU(2) flavor symmetry. These calculations are based on Lüscherʹs method in which finite size effects in two-particle energies are exploited. The results from Monte Carlo simulations with staggered fermions for the lightest meson (“pion”) are in good agreement with the analytical strong-coupling prediction. Furthermore, the mass spectrum of low-lying mesonic states is investigated numerically. We find a surprisingly rich spectrum in the mass region [mπ, 4mπ].