Related papers: Theoretical Progress in QCD at small $x$
Explicit expressions for the non-singlet and singlet structure functions g_1 in the small-x region are obtained. They include the total resummation of the double- and single- logarithms of x and account for the running QCD coupling effects.…
We summarize our recent results on small x resummation in full QCD with n_f quark flavours and discuss their phenomenological impact in the extraction of parton distributions from present day structure function data and their extrapolation…
By using the concept of duality between direct channel resonances and Regge exchanges we relate the small- and large-$x$ behavior of the structure functions. We show that even a single resonance exhibits Bjorken scaling at large $Q^2$.
We review QCD based descriptions of diffractive deep inelastic scattering emphasizing the role of models with parton saturation. These models provide natural explanation of such experimentally observed facts as the constant ratio of…
We consider in detail the Q^2 -dependence of the DIS structure functions, with Q being the virtual photon momentum. Quite often this dependence is claimed to be originated by the Q^2-dependence of the QCD coupling. This leads to the small-x…
We study both polarized and unpolarized proton structure functions in the kinematical region of large Bjorken x and four-momentum transfer of few GeV^2. In this region the phenomenon of parton-hadron duality takes place between the smooth…
Recent results in polarized DIS are reviewed. Particular emphasis is placed on new measurements of transverse and longitudinal asymmetries, on the tests of the spin sum rules and on the analysis of the spin structure function $g_1$ in…
The perturbative QCD predictions for the small $x$ behaviour of the nucleon structure functions $F_{2,L}(x,Q^2)$ and $g_1(x,Q^2)$ are summarized. The importance of the double logarithmic terms for the small $x$ behaviour of the spin…
We present our study of the diffraction in charged current DIS. We analyse the perturbatively tractable excitation of heavy quarks, emphasizing the peculiarities of the Regge factorization breaking in excitation of open charm.
A review of theoretical models of diffractive structure functions in deep inelastic scattering (DIS) is presented with a view to highlighting distinctive features, that may be distinguished experimentally. In particular, predictions for the…
I discuss the problem of computing the structure functions for very heavy nuclei at small Bjorken x. The approximations used in this description are physically motivated, and recent computations reviewed.
We present a concise review of the theoretical status of the rare semileptonic B -> X_s l^+ l^- decays in the standard model. Particular attention is thereby devoted to the recent theoretical progress concerning, on the one hand the…
Over the past few months, the theory of QCD at high density has been advanced considerably. It provides new perspectives on, and controlled realizations of, confinement and chiral symmetry breaking. Here I survey the recent developments,…
We establish the short-time asymptotic behaviour of the Markovian semigroups associated with strongly local Dirichlet forms under very general hypotheses. Our results apply to a wide class of strongly elliptic, subelliptic and degenerate…
In this talk I give the mini-review on recent development in the non-linear QCD (at low $x$).
We test the consistency of the data on the nucleon structure functions with analyticity and the Regge asymptotics of the virtual Compton amplitude. By solving a functional extremal problem, we derive an optimal lower bound on the maximum…
A summary is given of the work which was presented in the working group C "Hadronic Final States" at the DIS04 workshop (Strbske Pleso, Slovakia, April 14-18, 2004). Progress in experimental tests and the theoretical development of…
Deep inelastic processes at small x are discussed in the framework of perturbative QCD at high energy. New results are presented on the quark anomalous dimensions beyond the leading logarithmic approximation, and their relevance to the…
A generalization of the leading-order DGLAP evolution at small x is performed for the non-singlet structure function by resumming the leading-order DGLAP anomalous dimension to all orders in the QCD coupling. Explicit expressions are…
Infrared divergences in the perturbative expansion of gauge theory amplitudes and cross sections have been a focus of theoretical investigations for almost a century. New insights still continue to emerge, as higher perturbative orders are…