Related papers: QCD Power Corrections from a Simple Model for the …
The following topics in perturbative QCD are reviewed: recent theoretical progress in higher-order calculations; soft-gluon resummation for hard-scattering processes at large $E_T$ and high $x$; low-$x$ behaviour of structure functions and…
We estimate the effects of non-perturbative physics on the differential distributions of infrared- and collinear-safe $e^+e^-$ event shape variables, by extending the notion of an infrared-regular effective strong coupling, which accounts…
New arguments are presented to emphasize the interest of the infrared finite coupling approach to power corrections in the context of Sudakov resummation. The more regular infrared behavior of some peculiar combinations of Sudakov anomalous…
We propose an extraction of the running coupling constant of QCD in the infrared region from experimental data on deep inelastic inclusive scattering at Bjorken x -> 1. We first attempt a perturbative fit of the data that extends NLO PQCD…
New arguments are presented in favor of the infrared finite coupling approach to power corrections in the context of Sudakov resummation. The more regular infrared behavior of some peculiar combinations of Sudakov anomalous dimensions, free…
We advocate the replacement of standard alphas(mu)-based QCD perturbation theory, in which the coupling and truncated perturbative predictions are dependent on the chosen renormalisation scheme, by a Lambda-based approach in which QCD…
A general strategy to solve the non-perturbative renormalization problem in lattice QCD, using finite-size techniques and numerical simulations, is described. As an illustration we discuss the computation of the axial current normalization…
We briefly summarize some recent theoretical developments in perturbative QCD, emphasizing new ideas which have led to widening the domain of applicability of perturbation theory. In particular, it is now possible to calculate efficiently…
A new approach of the QCD sum rule is proposed in which positive and negative-parity baryons couple with each other. With positive and negative-parity states explicitly taken into account, sum rules are derived by means of the dispersion…
This thesis is devoted to the study of some aspects of perturbative QCD, and in particular to the development of high-precision techniques for the extraction of physical parameters such as structure functions, parton distributions, and the…
One of the main open questions in physics is the understanding of the internal structure of the strongly interacting particles, or hadrons. It is still a challenge to describe consistently the dynamics of scattering processes and hadronic…
We use QCD sum rules to determine the difference between moments of the non-singlet structure functions. This combination decouples from the singular behaviour of the structure functions near x=1 as calculated in the quark-gluon basis and…
A recently proposed method of estimating the asymptotic behaviour of QCD perturbation theory coefficients is critically reviewed and shown to contain numerous invalid mathematical operations and unsubstantiated assumptions. We discuss in…
We discuss the solutions of QCD evolution equations with saturation in the high energy limit. We present a general argument showing that, in the running coupling case, the Next-to-Leading-Logarithmic (NLL) and higher order terms are…
String tension is introduced in perturbative QCD without hindering ultra violet renormalizability . The running gauge coupling constant remains unaltered and the string tension in the high energy limit vanishes asymptotically. Using 1/N…
We study effects of the running of the coupling in QCD at small Bjorken-x and in particular the ones related to gluon saturation. After introducing the steps taken to the derivation of the next to leading order nonlinear evolution equation,…
QCD sum rules for decuplet baryon two-point functions are investigated using a comprehensive Monte-Carlo based procedure. In this procedure, all uncertainties in the QCD input parameters are incorporated simultaneously, resulting in…
We present a novel method for precisely determining the QCD running coupling from $R_{\rm uds}$ measurements in electron-positron annihilation. When calculating the fixed-order perturbative QCD (pQCD) approximant of $R_{\rm uds}$, its…
The QCD corrections to the R_{\tau}^{12} moment of the invariant mass distribution in hadronic decays of the tau lepton are discussed. The next-to-next-to-leading order prediction is shown to be stable with respect to change of the…
Recently, we have introduced a unified theory to deal with perturbative and non-perturbative QCD contributions to hadronic structure functions in deep inelastic scattering. This formulation is realized by combining the coordinate space…