Related papers: Theoretical Aspects of HERA Physics
We review recent theoretical and phenomenological results on both the perturbative and non-perturbative Odderon. The HERA type of experiments constitutes a direct probe of the Odderon.
We outline theoretical ideas on the soft and hard dynamics of strong high-energy interactions and discuss promising directions for future high-energy experimental investigations including the ones which would allow one to reveal the…
High Q^2 NC and CC cross-sections as measured at HERA can give information on two distinct areas of current interest. Firstly, supposing that all the electroweak parameters are well known, these cross-sections may be used to give…
The large rapidity gap events, observed at HERA, have changed considerably our physical picture of deep inelastic scattering during the past years. We review the present theoretical understanding of diffractive DIS with emphasis on the…
The description of the QCD dynamics in the kinematical range which will be probed in the future electron - hadron colliders is still an open question. Although phenomenological studies indicate that the gluon number fluctuations, which are…
The small-$x$ evolution of protons is determined from numerical solutions of the JIMWLK equations, starting from an initial condition at moderate $x$ for a finite size proton. The resulting dipole amplitude is used to calculate the total…
I review a recent progress in understanding the Regge asymptotics in perturbative QCD including the behaviour of the structure functions of DIS at small Bjorken $x$.
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…
We investigate the Q^2 evolution of parton distributions at small x values, obtained in the case of flat initial conditions. The results are in excellent agreement with deep inelastic scattering experimental data from HERA.
The latest results from the H1 and ZEUS collaborations which challenge the QCD description of high energy $ep$ collisions are presented. Data from HERA continue to provide precision measurements and are compared to the latest theoretical…
There has been a revived interest in small-x resummation in recent times. The main motivation was its success in describing small-x HERA data without the inclusion of non-perturbative corrections. In this contribution I will review the…
We review recent HERA data on the structure function F_2 at small x and large Q^2. We show that the salient features of the data are revealed by comparing them to the double asymptotic scaling behaviour which F_2 is predicted to satisfy in…
The photoproduction of Drell-Yan lepton pairs at HERA is studied. We show that in the backward rapidity region the cross section is strongly sensitive to the small-$x$ behaviour of the quark distributions in the proton, and that with…
We calculate the small-$x$ evolution of protons with finite size by solving numerically the JIMWLK evolution equation. The initial condition is constrained by the HERA measurements of charm reduced cross section and of exclusive vector…
Diffractive processes in photon-proton interactions at HERA offer the opportunity to improve the understanding of the transition between the soft, non-perturbative regime in hadronic interactions at $Q^2 = 0$ and the perturbative region at…
I review recent developments in the study of the low-x partonic content of protons and nuclei, with a focus on the latter, as one expects possible deviations from linear QCD evolution to be most pronounced in that case. I give examples of…
Measurements of charmed particle cross sections at HERA in the photoproduction and deep inelastic regimes are reviewed. The status of the comparison with perturbative QCD calculations is discussed.
The results of complementary tests of perturbative QCD in DIS at large centre-of-mass energies at HERA are presented. The analysis of event shape variables allows for the investigation of approaches to understand aspects of non-perturbative…
We calculate in next-to-leading order inclusive cross sections of single-particle production via resolved photons in $ep$ collisions at HERA. Transverse-momentum and rapidity distributions are presented and the scale dependence is studied.…
Recent results from the HERA ep collider are discussed with emphasis on the transition from short to long distance phenomena in QCD. The results cover inclusive ep scattering, inclusive diffractive scattering, vector meson production, and…