Related papers: Analytic and "frozen" QCD coupling constants up to…
We computed the static potential and Wilson loops to $O(\alpha^2)$ in perturbation theory for different lattice quark and gluon actions. In general, we find short distance lattice data to be well described by ``boosted perturbation…
The \alpha_s^2 correction to the Ellis-Jaffe sum rule for the structure function g_1 of polarized deep inelastic lepton-nucleon scattering is calculated.
The QCD expectations concerning the deep inelastic lepton - hadron scattering at low $x$ and their phenomenological implications for HERA are summarised. Theoretical predictions for the structure function $F_2(x,Q^2)$ based on the leading…
An updated next-to-leading order (NLO) QCD analysis of the spin asymmetries A_1^N(x,Q^2) and parton distributions delta f(x,Q^2) in longitudinally polarized deep-inelastic lepton-nucleon scattering is presented within the framework of the…
Standard power-behaved contributions in QCD arising from non-perturbative effects at low scale can be described, as shown by Dokshitzer, Marchesini and Webber, with the notion of an infrared regular effective coupling. In their approach, a…
In this contribution to the proceedings, we analyze the transition from perturbative and non- perturbative QCD embedded in the coupling constant. In the study of quark-hadron duality, we suggest that the realization of the latter is related…
Going beyond the linearized study has been a longstanding problem in the theory of Landau damping. In this paper we establish exponential Landau damping in analytic regularity. The damping phenomenon is reinterpreted in terms of transfer of…
Since the x dependence of the axial-anomaly effect in inclusive polarized deep inelastic scattering is fixed, the transformation from the $\bar{MS}$ scheme to different factorization schemes are not arbitrary. If the quark spin distribution…
In the framework of the analytic approach to Quantum Chromodynamics a new model for the strong running coupling has recently been developed. Its underlying idea is to impose the analyticity requirement on the perturbative expansion of the…
We review the present status of polarized structure functions measured in deep-inelastic scattering. We discuss the x and Q^2 dependence of the structure function g_1, and how it can be used to test perturbative QCD at next-to-leading order…
We report on the extraction of the higher twist contributions to F_2 and R = sigma_L/sigma_T from the global NLO and NNLO QCD fits to lepton nucleon scattering data over a wide range of Q^2. The NLO fits require both target mass and higher…
The status of the twist--2 and the twist--3 integral relations between polarized structure functions in deep inelastic scattering for electromagnetic and electroweak interactions is reviewed. One novel integral relation for the twist--3…
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 investigate weakly coupled spin-1/2 ladders in a magnetic field. The work is motivated by recent experiments on the compound (C5H12N)2CuBr4 (BPCB). We use a combination of numerical and analytical methods, in particular the density…
A new structure function analysis of CCFR deep inelastic nu-N and nubar-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x=0.0045 and Q^2=0.3 GeV^2. Comparisons to charged lepton scattering data…
We present the first computation of next-to-next-to-leading order (NNLO) pure QED and mixed QCD$\otimes$QED corrections to unpolarized and polarized semi-inclusive deep-inelastic scattering (SIDIS). Building on our previous NNLO QCD…
Sensitivity to the strong coupling $\alpha_S(M^2_Z)$ is investigated using existing Deep Inelastic Scattering data from HERA in combination with projected future measurements from the Electron Ion Collider (EIC) in a next-to-next-to-leading…
We report on the first calculation of the structure function g_1 in polarised deep-inelastic scattering to the third order in massless perturbative QCD. The calculation follows the dispersive approach already used for the corresponding…
We compute the complete third-order contributions to the coefficient functions for the longitudinal structure function F_L, thus completing the next-to-next-to-leading order (NNLO) description of unpolarized electromagnetic deep-inelastic…
A brief summary is given on recent determinations of $\Lambda_{\rm QCD}$ and $\alpha_s(M_Z^2)$ from deeply inelastic structure functions.