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One-loop renormalisation of quark bilinears for overlap fermions with improved gauge actions

R. Horsley·H. Perlt·P. E. L. Rakow·G. Schierholz·A. Schiller
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Abstract

We compute lattice renormalisation constants of local bilinear quark operators for overlap fermions and improved gauge actions. Among the actions we consider are the Symanzik, Lüscher-Weisz, Iwasaki and DBW2 gauge actions. The results are given for a variety of $ρ$ parameters. We show how to apply mean field (tadpole) improvement to overlap fermions. The question, what is a good gauge action, is discussed from the perturbative point of view. Finally, we show analytically that the gauge dependent part of the self-energy and the amputated Green functions are independent of the lattice fermion representation, using either Wilson or overlap fermions.

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R. Horsley, H. Perlt, P. E. L. Rakow, G. Schierholz, A. Schiller. 2005-01-21. One-loop renormalisation of quark bilinears for overlap fermions with improved gauge actions. https://doi.org/10.1016/j.nuclphysb.2005.01.044

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