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The quest for the quark–gluon plasma

Abstract

High-energy collisions between heavy nuclei have in the past 20 years provided multiple indications of a deconfined phase of matter that exists at phenomenally high temperatures and pressures. This 'quark–gluon plasma' is thought to have permeated the first microseconds of the Universe. Experiments at the Large Hadron Collider should consolidate the evidence for this exotic medium's existence, and allow its properties to be characterized.

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Figure 1: Fireball remnants.
Figure 2: Equilibrium parameters of the fireball.
Figure 3: Geometry of matter during a nuclear collision.
Figure 4: Preliminary PHENIX results for the suppression factor RAA out to high pt for π0 and η mesons.
Figure 5: Scaled energy density ɛ/T4 as a function of the temperature calculated in lattice quantum chromodynamics6.
Figure 6: Charmonium suppression.

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Correspondence should be addressed to J.S. (stachel@physi.uni-heidelberg.de).

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Braun-Munzinger, P., Stachel, J. The quest for the quark–gluon plasma. Nature 448, 302–309 (2007). https://doi.org/10.1038/nature06080

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