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arXiv · hep-th/9309128

The massive Schwinger model with $SU(2)_{f}$ on the light cone

Koji Harada·Takanori Sugihara·Masa-aki Taniguchi·Masanobu Yahiro
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Abstract

The massive Schwinger model with two flavors is studied in the strong coupling region by using 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 the strong couplings, where $m$ is the fermion mass. We also find that the lightest isosinglet is not in the valence state (``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 pion at $m=1.0\times10^{-3}(e/\sqrtπ)$, while Coleman predicted that the ratio is $\sqrt3$ in the strong coupling limit. The ``pion decay constant'' is calculated to be 0.3945.

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Koji Harada, Takanori Sugihara, Masa-aki Taniguchi, Masanobu Yahiro. 1993-09-24. The massive Schwinger model with $SU(2)_{f}$ on the light cone. https://doi.org/10.1103/physrevd.49.4226

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