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The running coupling in lattice Landau gauge with unquenched Wilson fermion and KS fermion

Sadataka Furui·Hideo Nakajima
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Abstract

The running coupling of the Wilson fermon(JLQCD/CP-PACS) and that of Kogut-Susskind(KS) fermion(MILC) are measured in the lattice Landau gauge QCD in $\widetilde{MOM}$ scheme. The quark propagator of the KS fermion is also measured and we find that it is infrared suppressed. The renormalization factor of the running coupling and the tadpole renormalization define the scale of the quark wave function. Effects of the $A_μ^2$ condensates of a few GeV$^2$ are observed in the running coupling and also in the quark propagator.

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Sadataka Furui, Hideo Nakajima. 2005-11-22. The running coupling in lattice Landau gauge with unquenched Wilson fermion and KS fermion. https://arxiv.org/abs/hep-lat/0509035

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