Tadpole-improved SU(2) lattice gauge theory - art. no. 014502.

A comprehensive analysis of tadpole-improved SU(2) lattice gauge theory is made. Simulations are done on isotropic and anisotropic lattices, with and without improvement. Two tadpole renormalization schemes are employed one u sing average plaquettes, the other using mean links in the Landau gauge. Si mulations are done with spatial lattice spacings a(s) in the range of about 0.1-0.4 fm. Results are presented for the static quark potential, the reno rmalized lattice anisotropy a(t)/a(s) (where a(t) is the ''temporal" lattic e spacing), and for the scalar and tensor glueball masses. Tadpole improvem ent significantly reduces discretization errors in the static quark potenti al and in the scalar glueball mass, and results in very little renormalizat ion of the bare anisotropy that is input to the action. We also find that t adpole improvement using mean links in the Landau gauge results in smaller discretization errors in the scalar glueball mass (as well as in the static quark potential), compared to when average plaquettes are used. The possib ility is also raised that further improvement in the scalar glueball mass m ay result when the coefficients of the operators which correct for discreti zation errors in the action are computed beyond the tree level. [S0556-2821 (98)00623-7].