4 research outputs found
Space-time analysis of reaction at RHIC
Space-time information about the Au-Au collisions produced at RHIC are key
tools to understand the evolution of the system and especially assess the
presence of collective behaviors. Using a parameterization of the system's
final state relying on collective expansion, we show that pion source radii can
be tied together with transverse mass spectra and elliptic flow within the same
framework. The consistency between these different measures provide a solid
ground to understand the characteristics of collective flow and especially the
possible peculiar behavior of particles such as Xi, Omega or phi. The validity
of the short time scales that are extracted from fits to the pion source size
is also addressed. The wealth of new data that will soon be available from
Au-Au collisions at sqrt{s_{NN}} = 200 GeV, will provide a stringet test of the
space-time analysis framework developped in these proceedings.Comment: Invited talk given at the SQM2003 conference (March 2003), to be
published in Journal of Physics G. 10 pages, 3 figure
Multiplicity of charged particles in Pb-Pb collisions at SPS energies
The multiplicity of charged particles in the central rapidity region has
been measured by the NA57 experiment in Pb-Pb collisions at the CERN SPS
at two beam momenta: 158 A GeV/c and 40 A GeV/c. The value of dN(ch)/d
eta at the maximum has been determined and its behaviour as a function
of centrality has been studied in the centrality range covered by NA57
(about 50% of the inelastic cross section). The multiplicity increase
is compatible with a logarithmic dependence on the centre of mass
energy. The results are compared with those from other experiments and
with the VENUS and RQMD models
Multiplicity of charged particles in Pb-Pb collisions at SPS energies
The multiplicity of charged particles in the central rapidity region has
been measured by the NA57 experiment in Pb-Pb collisions at the CERN SPS
at two beam momenta: 158 A GeV/c and 40 A GeV/c. The value of dN(ch)/d
eta at the maximum has been determined and studied as a function of
centrality within the range covered by NA57 (about 55% most central
part of the inelastic cross section). The central rapidity multiplicity
varies roughly linearly with the number of wounded nucleons
(participants) and increases approximately logarithmically with the
centre of mass energy