Lattice calculation of 1/p² corrections to αs and of ΛQCD in the MOM scheme.

Abstract

We report on very strong evidence of the occurrence of power terms in α^MOM(p), the QCD running coupling constant in the ^MOM scheme, by analyzing non-perturbative measurements from the lattice three-gluon vertex between 2.0 and 10.0GeV at zero flavor. While putting forward the caveat that this definition of the coupling is a gauge dependent one, the general relevance of such an occurrence is discussed. We fit (nf=0) MS = 237 ± 3+ 0 −10MeV in perfect agreement with the result obtained by the ALPHA group with a totally different method. The power correction to α^MOM(p) is fitted to (0.63 ± 0.03+ 0.0 − 0.13)GeV²/p².