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arXiv · nucl-th/0207016

The reconstructed final state of Au + Au collisions from PHENIX and STAR data at sqrt{s}=130 AGeV - indication for quark deconfinement at RHIC

Abstract

The final state of Au + Au collisions at sqrt{s}=130 AGeV at RHIC has been reconstructed within the framework of the Buda-Lund hydrodynamical model, by performing a simultaneous fit to final data on two-particle Bose-Einstein correlations of the STAR and PHENIX Collaborations, and final identified single particle spectra as measured by the PHENIX Collaboration. The results indicate a strongly three-dimensional expansion with a four-velocity field that is almost a spherically symmetric Hubble flow. We find large transverse geometrical source sizes, R_G = 9.8 +- 1.2 fm, a relatively short mean freeze-out time of tau0 = 6.1 +- 0.3 fm/c and a short duration of particle emission, Delta_tau = 0.02 +- 1.5 fm/c. Most strikingly, we find an indication for a hot central part or the hydrodynamically evolving core, characterized by a central temperature of T0 = 202 +- 13 MeV, that is close to (or even above) the deconfinement temperature of the quark-hadron phase transition. The best fit indicates a cold surface temperature of T_s = 110 +- 16 MeV. When the possibility of the hot center is excluded, the confidence level of the fit decreases from 28.9 % to 1.2 %. Predictions are made for the rapidity dependence of the slope parameters, for the transverse mass dependence of the rapidity-width of the single-particle spectra, and for the transverse velocity dependence of the non-indentical particle correlations.

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T. Csorgo, A. Ster. 2002-07-05. The reconstructed final state of Au + Au collisions from PHENIX and STAR data at sqrt{s}=130 AGeV - indication for quark deconfinement at RHIC. https://doi.org/10.1556/aph.17.2003.2-4.13

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