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arXiv · hep-ph/9801393

Equation of State, Flow, Fluctuations and $J/ψ$ suppression

E. V. Shuryak
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Abstract

Radial flow observed at AGS/SPS energies is very strong, with collective velocities of matter reaching about 0.5c for central collisions of the heaviest ions. The lattice-based Equation of State (EOS) is however rather soft, due to the QCD phase transition. We show that both statements are consistent only if proper kinetic-based treatment of the freeze-out is made. In fact chemical and thermal freeze-out happen at quite different conditions, especially at SPS. Event-by-event fluctuations can shed new light on this problem. We also propose new model of "anomalous" $J/ψ$ suppression found for PbPb collisions, related it to prolonged lifetime of dense matter due the "softest point" of the EOS.

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E. V. Shuryak. 1998-01-22. Equation of State, Flow, Fluctuations and $J/ψ$ suppression. https://doi.org/10.1016/s0375-9474(98)00414-x

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