v 1 1 3 Se p 19 99 Thermalization and Flow in 158 A GeV Pb + Pb Collisions
نویسنده
چکیده
The WA98 experiment at the CERN SPS measures Pb+Pb Collisions at 158 AGeV. The scaling properties of the charged particle multiplicity at midrapidity with the number of participants are studied using the SPMD and the MIRAC detector. Neutral pion spectra obtained from the LEDA detector are compared to hydrodynamical parametrizations. The collective flow in the target fragmentation region has been studied using the Plastic Ball detector. The results exhibit a strong dependence on centrality and rapidity.
منابع مشابه
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We report measurements of Ξ and Ξ + hyperon absolute yields as a function of rapidity in 158 GeV/c Pb+Pb collisions. At midrapidity, dN dy = 2.29± 0.12 for Ξ, and 0.52 ± 0.05 for Ξ+, leading to the ratio of Ξ+/Ξ−=0.23±0.03. Inverse slope parameters fitted to the measured transverse mass spectra are of the order of T ≈ 300 MeV near mid-rapidity. The estimated total yield of Ξ particles in Pb+Pb ...
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Two-particle correlation functions of negative hadrons over wide phase space, and transverse mass spectra of negative hadrons and deuterons near mid-rapidity have been measured in central Pb+Pb collisions at 158 GeV per nucleon by the NA49 experiment at the CERN SPS. A novel Coulomb correction procedure for the negative two-particle correlations is employed making use of the measured oppositely...
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Hadronic yields and yield ratios observed in Pb+Pb collisions at the SPS energy of 158 GeV per nucleon are known to resemble a thermal equilibrium population at T = 180 ± 10 M eV , also observed in elementary e + + e − to hadron data at LEP. We argue that this is the universal consequence of the QCD parton to hadron phase transition populating the maximum entropy state. This state is shown to s...
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تاریخ انتشار 1999