Parton Distributions and the Strong Coupling Strength α s

We study the global analysis for parton distributions as a function of the QCD strong coupling strength α s , and present a new series of distributions that span the range 0.110 < α s (m Z) < 0.128. We use these distributions to explore the correlation between α s and the gluon distribution; the viability of global analysis as a method to measure α s ; and the dependence on α s of predictions for W , Z, inclusive jet, and Higgs boson production (b ¯ b → H and gg → H) cross sections at the Tevatron and the LHC. We find that the uncertainty in α s is the dominant source of uncertainty for inclusive jet production at moderately small p T and for Higgs production at intermediate masses in the standard model.