2,960 research outputs found
Strangeness enhancement and Energy dependence in Heavy Ion Collisions
The canonical statistical model analysis of strange and multistrange hadron
production in central A-A relative to p-p/p-A collisions is presented over the
energy range from GeV up to GeV. It is shown that
the relative enhancement of strange particle yields from p-p/p-A to A-A
collisions substantially increases with decreasing collision energy. It is
largest at GeV, where the enhancement of and
is of the order of 100, 20 and 3, respectively. In terms of the model
these results are due to the canonical suppression of particle thermal phase
space at lower energies, which increases with the strangeness content of the
particle and with decreasing size of the collision fireball. The comparison of
the model with existing data on energy dependence of the kaon/pion ratio is
also discussed
The canonical effect in statistical models for relativistic heavy ion collisions
Enforcing exact conservation laws instead of average ones in statistical
thermal models for relativistic heavy ion reactions gives raise to so called
canonical effect, which can be used to explain some enhancement effects when
going from elementary (e.g. pp) or small (pA) systems towards large AA systems.
We review the recently developed method for computation of canonical
statistical thermodynamics, and give an insight when this is needed in analysis
of experimental data.Comment: 4 pages, 3 figures. Talk given in Strangeness in Quark Matter,
Frankfurt am Main 2001. Submitted to J. Phys. G: Nucl. Part. Phy
Group projection method in statistical systems
We discuss an application of group theoretical methods to the formulation of
the thermodynamics of systems constrained by the conservation laws described by
a semi--simple compact Lie group. A general projection method that allows to
construct a partition function for a given irreducible representation of the
Lie group is outlined. Applications of the method in Lattice Gauge Theory (LGT)
for non--zero baryon number and in the phenomenological description of particle
production in ultrarelativistic heavy ion collisions are also indicated.Comment: Invited talk presented at the XXIV International Colloquium on Group
Theoritical Methods in Physic
Heavy ion collisions and lattice QCD at finite baryon density
We discuss a relation between the
QCD thermodynamics obtained from a statistical analysis of particle
production in heavy ion collisions at SPS and RHIC energies and recent LGT
results at finite chemical potential. We show that basic thermodynamic
properties obtained from the phenomenological statistical operator of a hadron
resonance gas that describes particle yields in heavy ion collisions are
consistent with recent LGT results. We argue that for the equation
of state derived from
Monte--Carlo simulations of two quark--flavor QCD at finite chemical
potential can be well described by a hadron resonance gas when using the same
set of approximations as used in LGT calculations. We examine the influence of
a finite quark mass on the position of the deconfinement transition in
temperature and chemical potential plane.Comment: To appear in the proceedings of 17in International Conference on
Ultra Relativistic Nucleus-Nucleus Collisions (Quark Matter 2004), Oakland,
California, 11-17 Jan 200
Conservation Laws and Particle Production in Heavy Ion Collisions
We discuss the role of the conservation laws related with U(1) internal
symmetry group in the statistical model description of particle productions in
ultrarelativistic heavy ion collisions. We derive and show the differences in
particle multiplicities in the canonical and the grand canonical formulation of
quantum number conservation. The time evolution and the approach to chemical
equilibrium in the above ensembles is discussed in terms of kinetic master
equation. The application of the statistical model to the description of
(multi)strange particle yields at GSI/SIS and the SPS energies is also
presented.Comment: Invited talk at International Symposium on Hadron and Nuclei, Seoul,
Korea, 20-22 Feb 200
The statistical model in Pb-Pb collisions at the LHC
We briefly review the predictions of the thermal model for hadron production
in comparison to latest data from RHIC and extrapolate the calculations to LHC
energy. Our main emphasis is to confront the model predictions with the
recently released data from ALICE at the LHC. This comparison reveals an
apparent anomaly for protons and anti-protons which we discuss briefly. We also
demonstrate that our statistical hadronization predictions for J/
production agree very well with the most recent LHC data, lending support to
the picture in which there is complete charmonium melting in the quark-gluon
plasma (QGP) followed by statistical generation of J/ mesons at the phase
boundary.Comment: 4 pages, 3 figures, proceedings of QM201
Confronting LHC data with the statistical hadronization model
The most recent data from the CERN LHC are compared with calculations within
the statistical hadronization model. The parameters temperature und baryon
chemical potential are fitted to the data. The best fit yields a temperature of
156 MeV, slightly below the expectation from RHIC data. Proton yields are
nearly three standard deviations below this fit and possible reasons are
discussed.Comment: Proceedings of Strange Quark Matter 2013 Conference, to be published
in J. Phys.
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