IMPROVING THE TOPOLOGICAL CHARGE-DENSITY OPERATOR ON THE LATTICE

We analyze the properties of a class of improved lattice topological c harge density operators, constructed by a smearing-like procedure. By optimizing the choice of the parameters introduced in their definition , we find operators having (i) a much better statistical behavior as e stimators of the topological charge density on the lattice, i.e. much less noisy; (ii) a multiplicative renormalization much closer to one; (iii) a large suppression of the perturbative tail in the correspondin g lattice topological susceptibility.