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Separating perturbative and non-perturbative contributions to the plaquette

R. Horsley·P. E. L. Rakow·G. Schierholz
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Abstract

We try to separate the perturbative and non-perturbative contributions to the plaquette of pure SU(3) gauge theory. To do this we look at the large-n asymptotic behaviour of the perturbation series in order to estimate the contribution of the as-yet uncalculated terms in the series. We find no evidence for the previously reported Lambda^2 contribution to the gluon condensate. Attempting to determine the conventional Lambda^4 condensate gives a value of approximately 0.03(2) GeV^4, in reasonable agreement with sum rule estimates, though with very large uncertainties.

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R. Horsley, P. E. L. Rakow, G. Schierholz. 2001-10-29. Separating perturbative and non-perturbative contributions to the plaquette. https://doi.org/10.1016/s0920-5632(01)01870-9

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