SW action for the lattice Schwinger model
  We study some aspects of the ${\cal O}(a)$ improved Sheikholeslami-Wohlert (SW) action for the lattice Schwinger model. We find some improvement concerning the distribution of eigenvalues of the Dirac operator and of the masses but little or no improvement for rotational invariance of correlators or dispersion relations. 
Ch. Hoelbling, C.B. Lang and R. Teppner