Related papers: Quarkonium as a tool: cold nuclear matter effects
It is shown that a gravitationally collapsing black hole acts as an ultrahigh energy particle accelerator that can accelerate particles to energies inconceivable in any terrestrial particle accelerator, and that when the energy E of the…
In relativistic heavy ion collisions at RHIC and the LHC, a quark gluon plasma (QGP) is created for a short duration of about 10fm/c. Quarkonia (bound states of $c\bar{c}$ and $b\bar{b}$) are sensitive probes of this phase on length scales…
We find that in an opaque quark-gluon plasma, significant particle production at high transverse momenta can occur via acceleration of (initially) lower-momentum partons. This new mechanism, which is the opposite of parton energy loss (jet…
We investigate the cold nuclear matter effects on $J/\psi$ production, whose understanding is fundamental to study the quark-gluon plasma. Two of these effects are of particular relevance: the shadowing of the parton distributions and the…
Heavy quarkonium production in ultra-peripheral nuclear collisions (UPC) is described within the QCD dipole formalism. Realistic quarkonium wave functions in the $Q\bar Q$ rest frame are calculated by solving the Schr\"odinger equation with…
Bottomonium production is a powerful tool to investigate hadron collisions and the properties of the medium created in heavy-ion collisions. According to the color-screening model, these mesons give important information about the…
Little information is known about the polarization of gluons inside a longitudinally polarized proton. I report on the sensitivity of photoproduction experiments to it. Both jet and heavy quark production are considered.
The high density of scattered partons predicted in nuclear collisions at very high energy makes color screening effects significant. We explain how these screening mechanisms may suppress nonperturbative, soft QCD processes, permitting a…
We investigate the Mott effect for heavy quarkonia due to Debye screening of the heavy quark potential in a plasma of massless quarks and antiquarks. The influence of residual color correlation is investigated by coupling the light quark…
We reconsider a plasma with an anisotropy imposed on the momentum distribution of the system and study the real time static potential for quarkonia. The distribution function is normalised so as to preserve the particle number in an ideal…
We study QCD radiation in decay processes involving heavy particles. As input, the first-order gluon emission rate is calculated in a number of reactions, and comparisons of the energy flow patterns show a non-negligible process dependence.…
Heavy quarkonium theory has seen significant progress over the past years. Not only has the community steadily improved the understanding of fully equilibrated quarkonium using first principles lattice QCD studies, but it has taken major…
In this paper, we review the current status of the phenomenological study of quarkonium production in high energy collisions. After a brief introduction of several important models and effective field theories for quarkonium production, we…
This is an attempt to summarize the theoretical talks given at the First International Conference "Hard Probes '04", dedicated to the study of the properties of quark-gluon matter and its diagnostics with the hard processes. The talk covers…
The origin of flow-like effects in small systems, such as those produced in ultra-relativistic proton-proton and proton-lead collisions, is still widely debated. In this paper the goal is to look at possible consequences if indeed a…
We work out and review prospects for future quarkonium physics at HERA. We focus on the impact of color-octet contributions and discuss how measurements at HERA can be used to test the picture of quarkonium production as developed in the…
We consider the quarkonium diffusion, dissociation and recombination inside quark-gluon plasma. We compute scattering amplitudes in potential nonrelativistic QCD for relevant processes. These processes include the gluon absorption/emission…
In these lectures, I will attempt a pedagogical and qualitative introduction to the theory of equilibrium and thermalization of quark-gluon plasmas. I assume only that the reader is familiar with quantum field theory at zero temperature and…
Following the idea of nucleon clustering and light-nuclei production in relativistic heavy-ion collisions close to the QCD critical-end point, we address the quantum effects affecting the interaction of several nucleons at finite…
We explore the fundamental idea that there may be a role for the Casimir effect, via an uncertainty relation, in the generation of electron-positron and quark-gluon plasmas. We investigate this concept, reviewing the possible contribution…