Non-singlet QCD analysis of deep inelastic world data at O(αs3)

A non-singlet QCD analysis of the structure function F-2 (x, q(2)) in LO, NLO, NNLO and (NLO)-L-3 is performed based on the world data for charged lepton scattering. We determine the valence quark parton densities and present their parameterization and that of the correlated errors in a wide range of x and Q(2). In the analysis we determined the QCD-scale Lambda((MS) over bar)(QCD), N-f =4 = 265 +/- 27 MeV (NLO), 226 +/- 25 MeV ((NLO)-L-3), 234 +/- 26 MeV ((NLO)-L-3), with a remainder uncertainty of +/- 2 MeV for the yet unknown 4-loop anomalous dimension, corresponding to alpha(s)(M-Z(2)) = 0.1148 +/- 0.0019 NLO, 0.1134(-0.0021)(+0.0019) NNLO, 0.1141(-0.0022)(+0.0020) (NLO)-L-3. A comparison is performed to other determinations of the QCD scale and alpha(s)(M-Z(2)) in deeply inelastic scattering. The higher twist contributions of F-2(p)(x, Q(2)) and F-2(d)(x, Q(2)) are extracted in the large x region, subtracting the twist-2 contributions obtained in the NLO, NNLO and (NLO)-L-3 analysis. (c) 2007 Elsevier B.V. All rights reserved.