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arXiv · hep-ph/0012137

Elliptic flow at SPS and RHIC: from kinetic transport to hydrodynamics

P. F. Kolb·P. Huovinen·U. Heinz·H. Heiselberg
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Abstract

Anisotropic transverse flow is studied in Pb+Pb and Au+Au collisions at SPS and RHIC energies. The centrality and transverse momentum dependence at midrapidity of the elliptic flow coefficient v_2 is calculated in the hydrodynamic and low density limits. Hydrodynamics is found to agree well with the RHIC data for semicentral collisions up to transverse momenta of 1-1.5 GeV/c, but it considerably overestimates the measured elliptic flow at SPS energies. The low density limit LDL is inconsistent with the measured magnitude of v_2 at RHIC energies and with the shape of its p_t-dependence at both RHIC and SPS energies. The success of the hydrodynamic model points to very rapid thermalization in Au+Au collisions at RHIC and provides a serious challenge for kinetic approaches based on classical scattering of on-shell particles.

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P. F. Kolb, P. Huovinen, U. Heinz, H. Heiselberg. 2000-12-13. Elliptic flow at SPS and RHIC: from kinetic transport to hydrodynamics. https://doi.org/10.1016/s0370-2693(01)00079-x

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