| Abstract: We present the results of our QCD analysis for non-singlet unpolarized quark distributions and structure function F_2(x,Q^2) up to N^3LO. In this regards 4-loop anomalous dimension can be obtain from the Pad\'e approximations. The analysis is based on the Jacobi polynomials
expansion of the structure function. New parametrization are derived for the non-singlet quark distributions for the kinematic wide range of x and Q^2. The higher twist contributions of F_2^{p,d}(x,Q^2) are extracted in the large x region in N^3LO analysis. The values of
Lambda_{QCD} and a_s(M_z^2) are determined.
Time: November 25, 2009 | |