NNLO QCD contributions to the flavor non-singlet sector of F2(x,Q2){\bf {F_2(x,Q^2)}}

We present the results of our QCD analysis for nonsinglet unpolarized quark distributions and structure function $F_2(x,Q^2)$. New parameterizations are derived for the nonsinglet quark distributions for the kinematic wide range of $x$ and $Q^2$. The analysis is based on the Jacobi polynomials expansion of the structure function. The higher twist contributions of proton and deuteron structure function are obtained in the large $x$ region. Our calculations for nonsinglet unpolarized quark distribution functions based on the Jacobi polynomials method are in good agreement with the other theoretical models. The values of $\Lambda_{QCD}$ and $\alpha_s(M_z^2)$ are determined.Comment: 29 pages, 8 figure

Light-quark masses and renormalons

A brief review of the problem of the determination of light-quark masses from QCD sum rules for the correlators of scalar and pseudoscalar currents is given. Special attention is paid to the description of the large-$N_f$ results, obtained in collaboration with Broadhurst and Maxwell, for the scalar correlator, and estimates of its higher-order perturbative uncertainties within the renormalon-inspired large-$\beta_0$ expansion in the $\overline{\rm MS}$ scheme are given. Brief discussion is presented of the results of calculations of higher-order perturbative QCD corrections to the relation between pole and $\overline{\rm MS}$-scheme running-quark masses. Their comparison with the different estimates is also given.Comment: 14 pages, Contributed to the Proceedings of Quarks-2000 International Seminar, May 2000, Pushkin, Russia; minor typos are removed, 2 referencies are adde

Neutrino deep-inelastic scattering: new experimental and theoretical results

A review of recent experimental and theoretical studies of characteristics of neutrino deep-inelastic scattering is presented. Special attentition is paid to the determination of $\alpha_s$ and $1/Q^2$ non-perturbative effects from QCD fits to $xF_3$ data at different orders of perturbation theory, with the help of several theoretical methods.Comment: 17 pages, 3 figures; Contributed to the Proceedings of Les Recontre de la Vallee d'Aosta, La Thuile, Italy, March 4-10, 2001; more careful estimates of theoretical uncertainties of alpha_s(N_Z) with 3 significant digits is presented