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arXiv · hep-lat/9510023

Improved lattice operators: the case of the topological charge density

C. Christou·A. Di Giacomo·H. Panagopoulos·E. Vicari
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Abstract

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.

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C. Christou, A. Di Giacomo, H. Panagopoulos, E. Vicari. 1995-10-13. Improved lattice operators: the case of the topological charge density. https://doi.org/10.1103/physrevd.53.2619

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