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Operator product expansion and quark condensate from LQCD in coordinate space

V. Gimenez·V. Lubicz·F. Mescia·V. Porretti·J. Reyes
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Abstract

We perform an exploratory study of the operator product expansion of the quark propagator on the lattice at short distance in coordinate space. This permits a simple determination of the quark condensate, ^MS(2 GeV)=(-265\pm 5\pm 22 MeV)^3, and of the renormalization constant of the quark field, Z^MS(2 GeV)=0.871 \pm 0.003 \pm 0.020. This new method also provides a remarkable non-perturbative test of the OPE predictions at short distance in QCD.

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V. Gimenez, V. Lubicz, F. Mescia, V. Porretti, J. Reyes. 2005-10-20. Operator product expansion and quark condensate from LQCD in coordinate space. https://arxiv.org/abs/hep-lat/0510090

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