Measurement of alpha(s) from b(b)over-bar production at the cern p(p)over-bar collider

The UA1 Collaboration has recently improved its measurement of the beauty production cross-section by including explicit measurements of <b(b)over bar> correlations. Using these data we have determined the strong coupling constant alpha(s). The comparison of the measured cross-section for 2-body final states with O(alpha(s)(3)) QCD predictions yields a measurement of alpha(S)(20 GeV) = 0.145(-0.010exp-0.016 th)(+0.012+0.013), corresponding to alpha(S)(M(Z)) = 0.113(-0.006 exp-0.009 th)(+0.007+0.008). This is the first theoretically well-defined measurement of alpha(S) from a purely hadronic production process. Evaluating alpha(S) from cross-sections at different Q(2)-values we find that the running of alpha(S) is needed for internal consistency of the UA1 data.