22,443 research outputs found
Baryon number conservation and the cumulants of the net proton distribution
We discuss the modification of the cumulants of the net baryon and net proton
distributions due to the global conservation of baryon number in heavy-ion
collisions. Corresponding probability distributions and their cumulants are
derived analytically. We show that the conservation of baryon number results in
a substantial decrease of higher order cumulants. Based on our studies, we
propose an observable that is insensitive to the modifications due to baryon
number conservation.Comment: 6 pages, 4 figures, to be published in Phys. Rev.
Production of Dileptons in Heavy Ion Collisions at SPS-Energies
In this contribution we will discuss the production of low mass dileptons in
SPS-energy heavy ion collisions. We briefly review the current theoretical
situation before we turn to the analysis of the recent data for Pb+Au. We also
will discuss the role of baryons as a source for dileptons.Comment: Proceedings, XXXVII Winter Workshop, Bormio, Italy, Jan. 1999 8
pages, 6 figures, epsf styl
Event-by-event fluctuations in heavy ion collisions
We discuss the physics underlying event-by-event fluctuations in relativistic
heavy ion collisions. We will argue that the fluctuations of the ratio of
positively over negatively charged particles may serve as a unique signature
for the Quark Gluon Plasma.Comment: Contribution to the Proceedings of the International Workshop XXX on
Gross Properties of Nuclei and Nuclear Excitations, Hirschegg, Jan. 2002 and
to the Proceedings of the Krakow Epiphany Conference, Krakow, Jan. 200
Equilibrium in Heavy Ion Collisions
We discuss the question of equilibriation in heavy ion collisions and how it
can be addressed in experimentComment: Proceedings 19th Winter Workshop on Nuclear Dynamics, Breckenridge,
Co, 200
Dileptons from transport and hydrodynamical models
Transport and hydrodynamical models used to describe the expansion stage of a
heavy-ion collision at the CERN SPS give different dilepton spectrum even if
they are tuned to reproduce the observed hadron spectra. To understand the
origin of this difference we compare the dilepton emission from transport and
hydrodynamical models using similar initial states in both models. We find that
the requirement of pion number conservation in a hydrodynamical model does not
change the dilepton emission. Also the mass distribution from the transport
model indicates faster cooling and longer lifetime of the fireball.Comment: 5 pages, 2 Postscript figures, contribution to the `International
Workshop XXVIII on Gross Properties of Nuclei and Nuclear Excitations',
Hirschegg, Austria, January 16-22 200
Baryon number and strangeness: signals of a deconfined antecedent
The correlation between baryon number and strangeness is used to discern the
nature of the deconfined matter produced at vanishing chemical potential in
high-energy nuclear collisions at the BNL RHIC. Comparisons of results of
various phenomenological models with correlations extracted from lattice QCD
calculations suggest that a quasi-particle picture applies. At finite baryon
densities, such as those encountered at the CERN SPS, it is demonstrated that
the presence of a first-order phase transition and the accompanying development
of spinodal decomposition would significantly enhance the number of strangeness
carriers and the associated fluctuations.Comment: 10 pages, 4 figures, latex, to appear in the proceedings of the
Workshop on Correlations and Fluctuations in Relativistic Nuclear collisions,
(MIT, April 21-23,2005
Event-by-event fluctuations and the QGP
We discuss the physics underlying event-by-event fluctuations in relativistic
heavy ion collisions. We will emphasize how the fluctuations of particle ratios
can be utilized to explore the properties of the matter created in these
collisions. In particular, we will argue that the fluctutions of the ratio of
positively over negatively charged particles may serve as a unique signature
for the Quark Gluon Plasma.Comment: Proceedings Quark Matter 2001, Stony Brook, NY January 200
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