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Computing the perturbative gluon condensate

Georges Grunberg
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Abstract

The normalization of the gluon condensate and of renormalon-related power corrections in QCD is computed under the assumption that their ``perturbative'' part dominates over any eventual extra contribution from the non-trivial vacuum. The calculation is performed in the infrared finite coupling framework, assuming an infrared fixed point is present in the perturbative coupling down to low values of N_f. The freezing perturbative coupling is reconstructed using a Banks-Zaks expansion approach. Parameter-free predictions of the low energy moments of the coupling, which determine the process-independent part of the power corrections, are obtained for a number of choices of the running coupling.

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Georges Grunberg. 2001-07-30. Computing the perturbative gluon condensate. https://doi.org/10.1088/1126-6708%2F2001%2F07%2F033

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