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

A non-singlet QCD analysis of the structure function F2(x,q2) in LO, NLO, NNLO and N3LO 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 Q2. In the analysis we determined the QCD-scale ΛQCD,Nf=4MS¯=265±27MeV(NLO),226±25MeV(NNLO), 234±26MeV(N3LO), with a remainder uncertainty of ±2MeV for the yet unknown 4-loop anomalous dimension, corresponding to αs(MZ2)=0.1148±0.0019NLO,0.1134−0.0021+0.0019NNLO,0.1141−0.0022+0.0020N3LO. A comparison is performed to other determinations of the QCD scale and αs(MZ2) in deeply inelastic scattering. The higher twist contributions of F2p(x,Q2) and F2d(x,Q2) are extracted in the large x region, subtracting the twist-2 contributions obtained in the NLO, NNLO and N3LO analysis.