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arXiv · hep-th/0212171

Improved vector and scalar masses in the massive Schwinger model

C. Adam
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Abstract

The lowest (``vector'') and next-lowest (``scalar'') bound-state masses of the massive Schwinger model have been determined recently to a very high accuracy numerically on the lattice. Therefore, improved results for these bound-state masses from analytical calculations are of some interest. Here, we provide such improved results by employing both standard and renormal-ordered (fermion) mass perturbation theory, as well as a consistency condition between the two perturbative calculations. The resulting bound-state masses are in excellent agreement with the lattice results for small and intermediate fermion mass, and remain within 10% of the exact results even in the limit of very large fermion mass.

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C. Adam. 2002-12-15. Improved vector and scalar masses in the massive Schwinger model. https://doi.org/10.1016/s0370-2693(03)00051-0

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