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arXiv · 1207.0628

Non-perturbative renormalization in coordinate space for $N_f=2$ maximally twisted mass fermions with tree-level Symanzik improved gauge action

Krzysztof Cichy·Karl Jansen·Piotr Korcyl
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Abstract

We present results of a lattice QCD application of a coordinate space renormalization scheme for the extraction of renormalization constants for flavour non-singlet bilinear quark operators. The method consists in the analysis of the small-distance behaviour of correlation functions in Euclidean space and has several theoretical and practical advantages, in particular: it is gauge invariant, easy to implement and has relatively low computational cost. The values of renormalization constants in the X-space scheme can be converted to the MSbar scheme via 4-loop continuum perturbative formulae. Our results for $N_f=2$ maximally twisted mass fermions with tree-level Symanzik improved gauge action are compared to the ones from the RI-MOM scheme and show full agreement with this method.

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Krzysztof Cichy, Karl Jansen, Piotr Korcyl. 2012-07-03. Non-perturbative renormalization in coordinate space for $N_f=2$ maximally twisted mass fermions with tree-level Symanzik improved gauge action. https://doi.org/10.1016/j.nuclphysb.2012.08.006

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