3-,4-, and 5-flavor next-to-next-to-leading order parton distribution functions from deep-inelastic-scattering data and at hadron colliders

We determine the parton distribution functions (PDFs) in a next-to-next-to-leading order QCD analysis of the inclusive neutral-current deep-inelastic-scattering (DIS) world data combined with the neutrinonucleon DIS di-muon data and the fixed-target Drell-Yan data. The PDF evolution is performed in the N-f = 3 fixed-flavor scheme and supplementary sets of PDFs in the 4- and 5-flavor schemes are derived from the results in the 3-flavor scheme using matching conditions. The charm-quark DIS contribution is calculated in a general-mass variable-flavor-number (GMVFN) scheme interpolating between the zero-mass 4-flavor scheme at asymptotically large values of momentum transfer Q(2) and the 3-flavor scheme prescription of Buza-Matiounine-Smith-van Neerven (BMSN) at the value of Q(2) = m(c)(2). The results in the general-mass variable-flavor-number scheme are compared with those of the fixed-flavor scheme and other prescriptions used in global fits of PDFs. The strong coupling constant is measured at an accuracy of approximate to 1.5%. We obtain at next-to-next-to-leading order alpha(s)(M-Z(2)) = 0.1135 +/- 0.0014 in the fixed-flavor scheme and alpha(s)(M-Z(2)) = 0.1129 +/- 0.0014 applying the Buza-Matiounine-Smith-van Neerven prescription. The implications for important standard candle and hard scattering processes at hadron colliders are illustrated. Predictions for cross sections of W-+/-- and Z-boson, the top-quark pair, and Higgs-boson production at the Tevatron and the LHC based on the 5-flavor PDFs of the present analysis are provided.