Related papers: Parton Propagation in a Gluon Field
The perturbative QCD approach to quarkonium decay into a photon and hadrons is reconsidered. It is shown that a consistent treatment within perturbative QCD calls for the introduction of a fragmentation contribution which has been neglected…
We argue that the process of the proton diffraction into three jets in proton-nucleus scattering at LHC will allow to investigate the light-cone wave function of protons, generalized gluon densities in nuclei at small x, as well as the…
We study quantum fluctuations of the nucleon's parton densities by combining QCD factorization for hard processes with the notion of cross section fluctuations in soft diffraction. The fluctuations of the small-x gluon density are related…
At sufficiently high baryon density, a quark matter is expected to become a color superconductor because of the pairing forces mediated by gluons. The theoretical aspect of this novel phase of the strong interaction is reviewed with the…
This Ph.D.~thesis is divided into two distinct parts. The first part focuses on hard exclusive scattering processes in Quantum Chromodynamics (QCD) at high energies, while the second part delves into spin phenomena at the Large Hadron…
In this letter we address issues involved in quarkonium production near the boundaries of phase space. It is shown that higher-order non-perturbative contributions are enhanced in this kinematic region and lead to a breakdown of the…
We find a consistency between two different approaches of hard diffraction, namely the QCD dipole model and the Soft Colour Interaction approach. A theoretical interpretation in terms of S-Matrix and perturbative QCD properties in the small…
QCD gives rise to a rich spectrum of excited baryon states. Understanding their internal structure is important for many areas of nuclear physics, such as nuclear forces, dense matter, and neutrino-nucleus interactions. Generalized parton…
Processes of heavy quark production at TEVATRON energies are considered using the semihard (k_T factorization) QCD approach with emphasis of the BFKL dynamics of gluon distributions. We investigate the dependence of the p_T distribution of…
Generalized parton distributions at large $x$ are studied in perturbative QCD approach. As $x\to 1$ and at finite $t$, there is no $t$ dependence for the GPDs which means that the active quark is at the center of the transverse space. We…
A pQCD-based model for parton production and equilibration in ultrarelativistic heavy-ion collisions is reviewed. The model combines pQCD processes including initial and final state radiations together with string phenomenology for…
We investigate possible precursory phenomena of color superconductivity at finite temperature $T$ with an effective theory of QCD. It is found that the fluctuation of the diquark pair field exists with a prominent strength even well above…
The concept of color transparency is introduced. This new feature of QCD is characteristic of a gauge theory. It enables strong interactions to be studied in a new domain: scattering amplitudes of transversally small color singlet objects.…
To test a possible color-octet contribution of heavy quarkonium productions, we propose $\psi$'-productions for small-$p_T$ regions, where the color-singlet $\psi$' state cannot be produced by the gluon-gluon fusion owing to charge…
I discuss some questions related to hard scattering processes in nuclei and corrections to the leading twist approximation. The QCD factorization theorem requires that high energy partons do not lose energy while traversing the nucleus. I…
The hydrodynamic (hydro) model has been extensively applied to heavy ion data from the relativistic heavy ion collider (RHIC). Results are interpreted to conclude that a dense QCD medium nearly opaque to most partons, a strongly-coupled…
The generalized parton distributions and the generalized distribution amplitudes give access to a deeper understanding of the quark and gluon content of hadrons. In this short review, we select some new developments of their interesting…
Applications of perturbative QCD to hard exclusive electroproduction processes in the Bjorken limit at small invariant momentum transfer t bring in a new type of parton distributions which have hybrid properties, resembling both the parton…
Quantum Chromodynamics (QCD), the generally accepted theory for the strong interactions, describes the interactions between quarks and gluons. The strongly interacting particles that are seen in nature are hadrons, which are composites of…
The propagation of hard partons through spatially extended matter leads to medium-modifications of their fragmentation pattern. Here, we review the current status of calculations of the corresponding medium-induced gluon radiation, and how…