922 research outputs found
Centrality dependence of strangeness and (anti)hyperon production at BNL RHIC
We evaluate strangeness produced in Au--Au interactions at
GeV, as function of reaction participant number ,
and obtain the relative strange quark content at hadronization. Strange baryon
and antibaryon rapidity density yields are studied, relative to, and as
function of, participant number, and produced hadron yields.Comment: 4 pages including 4 figures, v2 text improvmen
Strangeness, Equilibration, Hadronization
In these remarks I explain the motivation which leads us to consider chemical
nonequilibrium processes in flavor equilibration and in statistical
hadroniziation of quark--gluon plasma (QGP). Statistical hadronization allowing
for chemical non-equilibrium is introduced. The reesults of fits to
RHIC-130 results, including multistrange hadrons, are shown to agree only
with the model of an exploding QGP fireball.Comment: 8 pages including one figure, discussion contribution at Strange
Quark Matter 2001, Frankfurt, submitted to J. Phys.
Hadronization of Expanding QGP
We discuss how the dynamics of an exploding hot fireball of quark--gluon
matter impacts the actual phase transition conditions between the deconfined
and confined state of matter. We survey the chemical conditions prevailing at
hadronization.Comment: 8 pages, presented at QGPTH05, Vienna, August 200
Gluon production, cooling and entropy in nuclear collisions
We study the cooling (heating) of a glue-parton gas due to production
(destruction) of particles and determine the associated production of entropy.
We incorporate sharing of the system energy among a changing number of
particles. We find that the entropy of an evolving glue-parton gas changes in
an insignificant range once the initial high temperature state has been formed,
despite a great change in particle number and temperature.Comment: Replaced for bad printing on US paper. 7 pages, LaTeX, 4 postscript
figure
Strangeness Chemical Equilibration in QGP at RHIC and LHC
We study, in the dynamically evolving QGP fireball formed in relativistic
heavy ion collisions at RHIC and LHC, the growth of strangeness yield toward
and beyond the chemical equilibrium. We account for the contribution of the
direct strangeness production and evaluate the thermal-QCD strangeness
production mechanisms. The specific yield of strangeness per entropy, s/S, is
the primary target variable. We explore the effect of collision impact
parameter, i.e., fireball size, on kinetic strangeness chemical equilibration
in QGP. Insights gained in study the RHIC data with regard to the dynamics of
the fireball are applied to the study strangeness production at the LHC. We use
these results and consider the strange hadron relative particle yields at RHIC
and LHC in a systematic fashion. We consider both the dependence on s/S and
directly participant number dependence.Comment: 21 pages, 13 figures, PRC in press. Strangeness production recomputed
with K-factor K=1.7. Particle yields recomputed with SHARE 2.
QGP fireball explosion
We identify the major physics milestones in the development of strange
hadrons as an observable for both the formation of quark-gluon plasma, and of
the ensuing explosive disintegration of deconfined matter fireball formed in
relativistic heavy ion collisions at 160--20A GeV. We describe the physical
properties of QGP phase and show agreement with the expectations based on an
analysis of hadron abundances. We than also demonstrate that the m_t shape of
hadron spectra is in qualitative agreement with the sudden breakup of a
supercooled QGP fireball.Comment: 10 pages, incl. 4 figures J. Phys. G in press; presented at
STRANGENESS2000 International Conference, Berkeley July 200
Generalization of Boltzmann Equilibration Dynamics
We propose a novel approach in the study of transport phenomena in dense
systems or systems with long range interactions where multiple particle
interactions must be taken into consideration. Within Boltzmann's kinetic
formalism, we study the influence of other interacting particles in terms of a
random distortion of energy and momentum conservation occurring when
multi-particle interactions are considered as binary collisions. Energy and
momentum conservation still holds exactly but not in each model binary
collision. We show how this new system differs from the Boltzmann system and we
note that our approach naturally explains the emergence of Tsallis-like
equilibrium statistics in physically relevant systems in terms of the long
since neglected physics of interacting and dense systems.Comment: 4 pages, references and clarifications adde
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