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

Understand

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.