Related papers: Asymptotic Freedom at Small x
We discuss the spectrum of open string and point particle excitations in QCD with various source representations. Some general relations are introduced and lattice results presented. In particular we discuss the short-distance behaviour,…
The longitudinal structure function in deep inelastic scattering is one of the observables from which the gluon distribution can be unfolded. Consequently, this observable can be used to constrain the QCD dynamics at small $x$. In this work…
We study the scattering of small color dipoles (e.g., heavy quarkonium states) at low energies. We find that even though the couplings of color dipoles to the gluon field can be described in perturbation theory, at large distances the…
In the framework of pertubative QCD it is argued that in the elastic $ed$-scattering at $Q^{2}\sim$ few $(GeV/c)^{2}$ the light-cone-frame helicity-flip amplitudes could not be omitted. The obtained $\frac{B}{A}$ ratio of Rosenbluth…
Deep-inelastic ep scattering data, taken with the H1 detector at HERA, are used to study event shape variables over a large range of "relevant energy" Q between 7 GeV and 100 GeV. Previously published analysis on thrust, jet broadening, jet…
In this paper the problem of noncommutative elastic scattering in a central field is considered. General formulas for the differential cross-section for two cases are obtained. For the case of high energy of an incident wave it is shown…
This paper is devoted to the scattering of photons at electrons in models of non-relativistic quantum mechanical particles coupled minimally to the soft modes of the quantized electromagnetic field. We prove existence of scattering states…
The potential between infinitely heavy quarks in a color singlet state is of fundamental importance in QCD. While the confining long distance part is inherently non-perturbative, the short-distance (Coulomb-like) regime is accessible…
We analyze diffractive deep inelastic scattering within perturbative QCD by studying lepton scattering on a heavy quark target. Simple explicit expressions are derived in impact parameter space for the photon wave function and the…
Several extensions of the standard model feature new colored states that besides modifying the running of the QCD coupling could even lead to the loss of asymptotic freedom. Such a loss would potentially diminish the Wilsonian fundamental…
A review on how the Odderon idea does appear in QCD is given. In the last years it has been developed a non-perturbative QCD approach based on the stochastic vacuum model and a perturbative one based on resummation techniques in the small x…
The heavy quark-antiquark potential is accessible in perturbative QCD and in lattice simulations. The perturbative short-distance part of the potential is contructed via a restricted Fourier transform, covering the momentum region where…
We discuss an alternative approach to studying the low energy limit of quantum general relativity. We investigate the low energy limit of a scattering cross-section for two massive scalar particles. Unlike calculations involving the…
This is an introduction to the use of QCD perturbation theory, emphasizing generic features of the theory that enable one to separate short-time and long-time effects. I also cover some important classes of applications: electron-positron…
The perturbative QCD fragmentation functions can be applied phenomenologically as a model for charm and bottom quark fragmentation into heavy-light mesons. The predictions by this model on the observables $P_V$ and $\langle z \rangle$ for…
Recent studies of the Q^2 dependence of ep scattering in the large x region and in the Q^2 range: 1 < Q^2 <leq 30 Gev^2, confirm the validity of the phenomenon of quark-hadron duality - the similarity of the deep inelastic (parton) and…
Excited hadrons are seen as resonances in the scattering of lighter stable hadrons like $\pi$, $K$ and $\eta$. Many decay into multiple final states necessitating coupled-channel analyses. Recently it has become possible to obtain…
We determine the diffractive scattering amplitude of a color-dipole on a nucleon using a non-perturbative model of QCD which contains only parameters taken from low-energy physics. This allows to relate specific features of the confinement…
We show that the O(Lambda) ambiguity in the pole mass can be fixed in a natural way by introducing a modified nonperturbative V-scheme momentum space coupling tilde-alphaV(q) where the confining contributions have been subtracted out. The…
The asymptotic behavior of the scattering amplitude for two scalar particles at high energies with fixed momentum transfers is studied. The study is done within the effective theory of quantum gravity based on quasi-potential equation. By…