  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.

High Energy Physics - Theory