Related papers: Non-Singlet QCD Analysis of the Structure Function…
We present a method to extract, in the leading and next-to-leading order approximations, the longitudinal deep-inelastic scattering structure function FL(x,Q2) from the experimental data by relying on a Froissart-bounded parametrization of…
We have studied the recently completed analytic all-N expressions for the four-loop anomalous dimensions corresponding to the next-to-next-to-next-to-leading order splitting functions for the non-singlet quark distribution in perturbative…
We present very simple non-integral relations between deep inelastic structure functions $F_L$, $F_2$ and the gluon distribution at small $x$ based on perturbative QCD which are useful for the phenomenological analysis of data at low $x$.…
We present the results of the next-to-next-to-leading order QCD analysis of the recently revised experimental data of the CCFR collaboration for the $xF_3$ structure function using the Jacobi polynomial expansion method. The effects of the…
A new approach to global QCD analysis is developed. The main ingredients are two QCD-based evolution equations. The first one is the Balitsky-Kovchegov nonlinear equation, which sums higher twists while preserving unitarity. The second…
The improved next-to-next-to-leading order (NNLO) QCD analysis of the experimental data of the CCFR collaboration for the $xF_3$ structure function is made. Theoretical ambiguities of the NNLO fits are estimated by means of the Pad\'e…
The leading order coefficients of the beta-function of QCD are computed in a large N_f expansion. They are in agreement with the three loop MSbar calculation. The method involves computing the anomalous dimension of the operator (G^2_{mu…
The strong coupling $\alpha_s$ is extracted with high precision through fits to lattice-QCD data for the static energy. Our theoretical framework is based on R-improving the three-loop fixed-order prediction for the static energy: we remove…
The virtual photon structure function $g_1^{\gamma}(x,Q^2,P^2)$, which can be obtained in polarized $e^{+}e^{-}$ colliding-beam experiments, is investigated for $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is the mass squared of the…
We use QCD sum rules to determine directly the leading-twist non-singlet operator matrix elements based on calculations of three-point correlator functions in configuration space. We find a different result from that obtained by integrating…
We performed NLO QCD analysis of the nonsinglet part of the combined SLAC/BCDMS data on $F_2$ with the extraction of $\alpha_s$ and high twist contribution. It was shown that the value of $\alpha_s$ obtained in the analysis is sensitive to…
In the present paper we summarize our results on the structure function g_1 and present explicit expressions for the non-singlet and singlet components of g_1 which can be used at arbitrary x and Q^2. These expressions combine the…
We give a short review of our recent analysis [1] of the deep inelastic scattering data (provided by BCDMS, SLAC, NMC) on F2 structure function in the non-singlet approximation with up to next-to-next-to-leading-order accuracy and analytic…
QCD evolution equations in minimal subtraction schemes have a hidden symmetry: One can construct three operators that commute with the evolution kernel and form an $SL(2)$ algebra, i.e. they satisfy (exactly) the $SL(2)$ commutation…
We describe the determination of the DIS structure functions $F_{2}$ and $F_{L}$ by using the singlet Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) and Altarelli-Martinelli equations at small values of $x$. The determination of the…
The small $x$ behavior of the flavor non-singlet $g_{1}$ structure function is analysed numerically by taking into account the all-order resummation of $\alpha_{s} \ln^{2}x $ terms. We include a part of the next-to-leading logarithmic…
We present the next-to-next-to-next-to-leading order (N^3LO) contributions to the non-singlet splitting functions for both parton distribution and fragmentation functions in perturbative QCD. The exact expressions are derived for the terms…
The results of LO {\it Fixed point} QCD (FP-QCD) analysis of the CCFR data for the nucleon structure function $~xF_3(x,Q^2)~$ are presented. The predictions of FP-QCD, in which the Callan-Symanzik $~\beta~$ function admits a {\it second…
We consider a system of evolution equations for quark and gluon structure functions satisfying the leading-logarithmic behaviour due to both QCD collinear $ \left(LLQ^2 \right) $ and infrared $ (LL1/x) $ singularities. We show that these…
The next-to-next-to-leading order (NNLO) QCD analysis is performed for the virtual photon structure functions which can be measured in the double-tag events in two-photon processes in $e^+e^-$ collisions. We investigate the perturbative QCD…