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arXiv · hep-lat/9909014

Resummation of Cactus Diagrams in Lattice QCD, to all Orders

H. Panagopoulos·E. Vicari
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Abstract

We show how to perform a resummation, to all orders in perturbation theory, of a certain class of gauge invariant tadpole-like diagrams in Lattice QCD. These diagrams are often largely responsible for lattice artifacts. Our resummation leads to an improved perturbative expansion. Applied to a number of cases of interest, e.g. the lattice renormalization of some two-fermion operators, this expansion yields results remarkably close to corresponding nonperturbative estimates. We consider in our study both the Wilson and the clover action for fermions.

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H. Panagopoulos, E. Vicari. 1999-09-08. Resummation of Cactus Diagrams in Lattice QCD, to all Orders. https://doi.org/10.1016/s0920-5632(00)91834-6

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