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The spectrum of the massive Schwinger model in the strong coupling region is obtained by using the light-front Tamm-Dancoff (LFTD) approximation up to including six-body states. We numerically confirm that the two-meson bound state has a negligibly small six-body component. Emphasis is on the usefulness of the information about states (wave functions). It is used for identifying the three-meson bound state among the states below the three-meson threshold. We also show that the two-meson bound state is well described by the wave function of the relative motion., 19 pages, RevTeX, 7 figures are available upon request; Minor errors have been corrected; Final version to appear in Phys.Rev.D

The massive Schwinger model with two flavors is studied in the strong coupling region by using the light-front Tamm-Dancoff approximation. The mass spectrum of the lightest particles is obtained numerically. We find that the mass of the lightest isotriplet ("pion") behaves as ${m}^{0.50}$ for strong coupling, where $m$ is the fermion mass. We also find that the lightest isosinglet is not in the valence state ("$\ensuremath{\eta}$") which is much heavier in the strong coupling region, but can be interpreted as a bound state of two pions. It is 1.762 times heavier than the pion at $m=1.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}(\frac{e}{\sqrt{\ensuremath{\pi}}})$, while Coleman predicted that the ratio is \ensuremath{\surd}3 in the strong coupling limit. The "pion decay constant" is calculated to be 0.3945.