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Theta Dependence of Meson Masses in the Small Mass Limit of the Massive Schwinger Model

M. Burkardt·K. Harada
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Abstract

We present a continuum formulation for $θ$-vacua in the massive Schwinger model on the light-front, where $θ$ enters as a background electric field. The effective coupling of the external field is partially screened due to vacuum polarization processes. For small fermion masses and small $θ$ we calculate the mass of the meson and find agreement with results from bosonization.

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M. Burkardt, K. Harada. 1997-12-03. Theta Dependence of Meson Masses in the Small Mass Limit of the Massive Schwinger Model. https://doi.org/10.1103/physrevd.57.5950

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