Alpha_s from the Lattice Potential

Abstract

We present an extensive study on the direct determination of the running coupling alpha_s from the static quark antiquark force at short distances, in quenched QCD. We find from our high statistics potential analysis that alpha_qq exhibits two-loop asymptotic behaviour for momenta as low as .5 GeV. As a result, we determine the zero flavour Lambda-parameter to be Lambda^0_MSBAR = 0.630(38)\sqrt{\sigma} = 293(18)^{+25}_{-63} MeV. A rough estimate of full QCD effects leads to the five flavour value alpha_MSBAR(m_Z) = .102^{+6}_{-11}. A comparison with other lattice results is made.

Comments: 6 pages (LaTeX) with 7 postscript figures (epsf required), Invited talk by K. Schilling held at Lattice '93 conference, Dallas, TX