Higher order corrections in perturbative quantum chromodynamics

We present a phenomenological analysis of higher order perturbative and kinematic corrections to deep-inelastic lepton-hadron scattering structure functions within the framework of Quantum Chromodynamics. The perturbative corrections involve higher order contribution in the strong coupling parameter, α/sub s/, as evaluated in the anti MS renormalization scheme and included in evolution equations for the non-singlet (valence quark) and singlet (sea quark and gluon) quark distribution functions. The kinematic corrections (inverse power) are included for the non-singlet equations and behavior of the resulting structure functions is compared with muon-proton data from CERN. The evolved structure functions with kinematic corrections included are consistent with data for the mass scale parameter #betta#/sub anti MS/ approx. = 0.4 and values of the higher twist expansion parameter μ1 less than or equal to 1.0. In the non-singlet case, kinematic and perturbative corrections are difficult to disentangle. In the singlet case, we ignore the kinematic corrections and evaluate the next-to-leading order perturbative corrections to the Mellin moments of the structure functions. These corrections cause the structure function to increase with q2 at low x and to diminish more rapidly at moderate to large x. We also compare various numerical schemes used in calculating leading and higher order evolution of the deep-inelastic structure functions. We believe the structure function analysis to be more reliable than moment analysis because it makes possible a more comprehensive comparison of the predictions of QCD with deep-inelastic data