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Rationale for UV-filtered clover fermions

Stefano Capitani·Stephan Durr·Christian Hoelbling
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Abstract

We study the contributions Sigma_0 and Sigma_1, proportional to a^0 and a^1, to the fermion self-energy in Wilson's formulation of lattice QCD with UV-filtering in the fermion action. We derive results for m_{crit} and the renormalization factors Z_S, Z_P, Z_V, Z_A to 1-loop order in perturbation theory for several filtering recipes (APE, HYP, EXP, HEX), both with and without a clover term. The perturbative series is much better behaved with filtering, in particular tadpole resummation proves irrelevant. Our non-perturbative data for m_{crit} and Z_A/(Z_m*Z_P) show that the combination of filtering and clover improvement efficiently reduces the amount of chiral symmetry breaking -- we find residual masses am_{res}=O(10^{-2}).

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Stefano Capitani, Stephan Durr, Christian Hoelbling. 2007-09-26. Rationale for UV-filtered clover fermions. https://doi.org/10.1088/1126-6708%2F2006%2F11%2F028

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