We analyze the properties of a class of improved lattice topological charge 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 better statistical behavior as estimators of the topological charge density on the lattice, i.e. less noisy; (ii) a multiplicative renormalization much closer to one; (iii) a large suppression of the perturbative tail (and other unphysical mixings) in the corresponding lattice topological susceptibility.
@article{arxiv.hep-lat/9510023,
title = {Improved lattice operators: the case of the topological charge density},
author = {C. Christou and A. Di Giacomo and H. Panagopoulos and E. Vicari},
journal= {arXiv preprint arXiv:hep-lat/9510023},
year = {2009}
}