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Renormal-order improvement of the Schwinger mass

Christoph Adam
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Abstract

The massive Schwinger model may be analysed by a perturbation expansion in the fermion mass. However, the results of this mass perturbation theory are sensible only for sufficiently small fermion mass. By performing a renormal-ordering, we arrive at a chiral perturbation expansion where the expansion parameter remains small even for large fermion mass. We use this renormal-ordered chiral perturbation theory for a computation of the Schwinger mass and compare our results with lattice computations.

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Christoph Adam. 1998-06-25. Renormal-order improvement of the Schwinger mass. https://doi.org/10.1142/s0217751x99002335

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