Related papers: Reggeon Interactions in Perturbative QCD
We study the covariant version of the quark-parton model, in which the general rules of the angular momentum composition are accurately taken into account. We demonstrate how these rules affect the relativistic interplay between the quark…
The fact that quark-quark, quark-gluon and gluon-gluon interactions are different sources of particle production in proton-proton collision at high energy is investigated in this work. The variation of the multiplicity and pseudo-rapidity…
Application of the effective action approach to amplitudes with loop integration is studied for collisions on two and three centers with possible gluon emission. A rule is formulated for the integration around pole singularities in the…
An overview is given on the experimental study of quark-gluon matter produced in relativistic nucleus-nucleus collisions, with emphasis on recent measurements at the Large Hadron Collider.
Heavy-quark observables in ultrarelativistic heavy-ion collisions, like the nuclear modification factor and the elliptic flow, give insight into the mechanisms of high-momentum suppression and low-momentum thermalization of heavy quarks.…
The drag and diffusion coefficients of charm and bottom quarks propagating through quark gluon plasma (QGP) have been evaluated within the framework of perturbative Quantum Chromodynamics (pQCD). Both radiative and collisional processes of…
The proton diffractive structure function $F_2^{D(3)}$ measured in the H1 and ZEUS experiments at HERA is analyzed in terms of both Regge phenomenology and perturbative QCD evolution. A new method determines the values of the Regge…
The Born amplitudes for quasi-multi-Regge kinematics of produced gluons are constructed in accordance with the Feynman rules including apart from usual Yang-Mills vertices also an infinite number of induced vertices. The new vertices…
Understanding the infrared sensitivity of perturbative predictions in QCD is important for assessing the magnitude of possible non-perturbative power corrections to processes with large momentum transfer. In renormalon models, this…
On the basis of perturbative QCD and the relativistic quark model we calculate relativistic corrections to the double $\eta_c$ meson production in proton-proton interactions at LHC energies. Relativistic terms in the production amplitude…
A selected set of topics along the borderline between perturbative and nonperturbative QCD in exclusive reactions are studied. Specific problems, related to different mechanisms of momentum transfer to an intact hadron, are discussed.…
The onset of equilibration in nuclear collisions can lead to related trends in the centrality dependence of the average transverse momentum, pt fluctuations and net charge fluctuations. We extend the transport description of S. Gavin (Phys.…
We consider b-jet production in the quasi-multi-Regge-kinematics approach based on the hypothesis of the gluon and quark Reggeization in the t-channel exchanges at the high energy. The data on various spectra of b-jet production measured by…
In this paper we investigate the possibility whether, in the extreme limit of high energies and large transverse distances, reggeon field theory might serve as an effective theory of high energy scattering for strong interactions. We…
We explore the highly non-perturbative hot region of the QCD phase diagram close to Tc by use of an imaginary chemical potential mu which avoids the sign problem. The number density and the quark number susceptibility are consistent with a…
Besides the ordinary hadrons, QCD allows the existence of states in which excitations of the gluonic field can play the role of valence particles, either alone in a glueball, or coupled to quarks in a hybrid. So, hybrid baryons, made of…
Based on both the constituent quark picture and the instanton model for QCD vacuum, we calculate the unpolarized and polarized gluon distributions in the constituent quark and in the nucleon. Our approach consists of the two main steps. At…
We discuss and compare different approaches to include gluon transverse momenta for heavy quark-antiquark pair production. The correlations in azimuthal angle and in heavy quark, heavy antiquark transverse momenta are studied in detail. The…
The interpretation of virtual gluons as ghosts in the non-linear gluonic structure of QCD permits the formulation and realization of a manifestly gauge-invariant and Lorentz covariant theory of interacting quarks/anti-quarks, for all values…
By expanding functions of parton fragmentation into a heavy hadron in the inverse of the heavy quark mass $m_Q$ we attempt to factorize them into perturbative- and nonperturbative parts. In our approach the nonperturbative parts can be…