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arXiv · 0901.4033

Logarithmic corrections to O(a^2) lattice artifacts

Janos Balog·Ferenc Niedermayer·Peter Weisz
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Abstract

We compute logarithmic corrections to the O(a^2) lattice artifacts for a class of lattice actions for the non-linear O(n) sigma-model in two dimensions. The generic leading artifacts are of the form $a^2[\ln(a^2)]^{(n/(n-2))}$. We also compute the next-to-leading corrections and show that for the case n=3 the resulting expressions describe well the lattice artifacts in the step scaling function, which are in a large range of the cutoff apparently of the form O(a). An analogous computation should, if technically possible, accompany any precision measurements in lattice QCD.

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Janos Balog, Ferenc Niedermayer, Peter Weisz. 2009-01-26. Logarithmic corrections to O(a^2) lattice artifacts. https://doi.org/10.1016/j.physletb.2009.04.082

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