Related papers: Parton Production Via Vacuum Polarization
Photoproduction in ultra-peripheral relativistic heavy-ion collisions displays many unique features, often involving quantum mechanical coherence and two-source interference between photon emission from the two ions. We review the recent…
We calculate the classical gluon field of a fast projectile passing through a dense medium. We show that this allows us to calculate both the initial state gluon production in proton-nucleus collisions and the final state gluon radiation…
We study azimuthal asymmetries in heavy quark pair production in unpolarized electron-proton and proton-proton collisions, where the asymmetries originate from the linear polarization of gluons inside unpolarized hadrons. We provide cross…
We discuss hadron production in heavy ion collisions at RHIC. We argue that hadrons at transverse momenta P_T < 5 GeV are formed by recombination of partons from the dense parton phase created in central collisions at RHIC. We provide a…
The hadroproduction of lepton pairs with mass Q and finite transverse momentum Q_T is described in perturbative QCD by the same partonic subprocesses as prompt photon production. We demonstrate that, like prompt photon production, lepton…
At the Relativistic Heavy Ion Collider (RHIC) collisions of heavy ions at nucleon-nucleon energies of 200 GeV appear to have created a new form of matter thought to be a deconfined state of the partons that ordinarily are bound in…
We discuss heavy quark production in High Parton Density QCD in quasi-classical approximation and including low-$x$ quantum evolution. We also consider an alternative approach based on the effect of pair production in external fields.
At very high energies, weak coupling, non-perturbative methods can be used to study classical gluon production in nuclear collisions. One observes in numerical simulations that after an initial ``formation'' time, the produced partons are…
The Pomeron-gluon-gluon interaction is considered in the QCD-based model for the charmed baryon production in the process Pomeron + p --> \Lambda_c^+ + X. The polarization of the produced heavy quark is induced effectively through the…
In ultrarelativistic heavy ion collisions the baryon-meson ratio is not fully understood in the intermediate-to-high transverse momentum region. Although quark coalescence methods combined with jet fragmentation yield results close to the…
In this paper we study the high energy exclusive photoproduction of heavy quarkonia pairs in the leading order of the strong coupling constant $\alpha_{s}$. In the suggested mechanism the quarkonia pairs are produced with opposite charge…
Heavy quarkonium production in the framework of the nonrelativistic quantum chromodynamics and leading order of the parton Reggeization approach at the Tevatron and LHC Colliders is discussed. The new results, which are reviewed in this…
We discuss electron-positron pair-production by super-intense, short laser pulses off the physical vacuum state locally deformed by (stripped) nuclei with large nuclear charges. Consequences of non-perturbative vacuum polarisation resulting…
Proton-proton collision is a simple system to investigate nuclear matter and it is considered to be a guide for more sophisticated processes in the proton-nucleus and the nucleus-nucleus collisions. In this article, we present a…
In the high energy regime, the proton structure consists of a very large number of particles called partons (quarks and gluons) that interact with each other, according to the theory of strong interactions, Quantum Chromodynamics (QCD).…
A phenomenological approach for neutron production in fast muon interactions has been considered. Linear approximation for photonuclear production mechanism at shallow depth has been deduced. Present calculations were compared with…
We study the production of heavy quarks, charm at BNL-RHIC ($\sqrt{s}$=200 GeV/nucleon) and CERN-LHC ($\sqrt{s}$=5.5 TeV/nucleon) and bottom at CERN-LHC from heavy ions colliding at relativistic energies. We consider initial fusion of…
In the early stage of ultrarelativistic heavy-ion collisions chiral symmetry is restored temporarily. During this so-called chiral phase transition, the quark masses change from their constituent to their bare values. This mass shift leads…
We present a general, model independent argument demonstrating that gluons produced in high energy hadronic collision are necessarily correlated in rapidity and also in the emission angle. The strength of the correlation depends on the…
We argue that the collinear factorization of the fragmentation functions in high energy hadron and nuclei collisions breaks down at transverse momenta kT < Qs/g due to high parton densities in the colliding hadrons and/or nuclei. We…