Perturbative QCD Potential and String Tension

Abstract

The leading non-perturbative contribution to the static QCD potential at r << 1/Lambda_QCD is known to be O(r^2) in operator-product expansion. It indicates that a "Coulomb+linear" potential at r <~ 1/Lambda_QCD is included in the perturbative QCD prediction of the potential. It was shown that this is indeed the case, and the "Coulomb+linear" potential has been systematically computed up to next-to-next-to-leading logarithmic order, in terms of the Lambda parameter in the MSbar scheme (Lambda_MSbar). We review the present status of the perturbative prediction for the QCD potential, which takes into account the theoretical breakthrough that took place around 1998.