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arXiv · 0811.0572

A comparison of the cut-off effects for Twisted Mass, Overlap and Creutz fermions at tree-level of Perturbation Theory

Krzysztof Cichy·Jenifer Gonzalez Lopez·Agnieszka Kujawa
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Abstract

In this paper we investigate the cutoff effects at tree-level of perturbation theory for three different lattice regularizations of fermions -- maximally twisted mass Wilson, overlap and Creutz fermions. We show that all three kinds of fermions exhibit the expected $O(a^2)$ scaling behaviour in the lattice spacing. Moreover, the size of these cutoff effects for the considered quantities i.e. the pseudoscalar correlation function $C_{PS}$, the mass $m_{PS}$ and the decay constant $f_{PS}$ is comparable for all of them.

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Krzysztof Cichy, Jenifer Gonzalez Lopez, Agnieszka Kujawa. 2008-11-04. A comparison of the cut-off effects for Twisted Mass, Overlap and Creutz fermions at tree-level of Perturbation Theory. https://arxiv.org/abs/0811.0572

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