N^3LO fits to xF_3 data : ${\alpha }_s$ vs 1/Q^2 contributions

Abstract

The results of approximate N^3LO and detailed NNLO fits to $x{F}_3$ data of the CCFR'97 collaboration are presented. We demonstrate that $1/Q^2$ non-perturbative corrections to $x{F}_3$ modeled by three independent procedures are shadowed by perturbative QCD effects, starting at the NNLO. Special attention is paid to revealing the role of the recently calculated NNLO corrections to the anomalous dimensions and $N^3$LO corrections to the coefficient functions of odd moments of $x{F}_3$ with $n\le 13$. The related values of ${\alpha }_s(M_Z)$ are extracted.

Comments: 5 pages, 1 figure, LaTeX; Contributed to the Proceedings of joint 6th Symposium RADCOR 2002 and 6th Zeuthen Workshop Loops and Legs in Quantum Field Theory, September 8-13, Kloster Banz, Germany; size of postscript figure fixed