Colour Deconfinement and J/Psi Suppression in High Energy Nuclear Collisions
1. Introduction 2. Charmomium Dissociation and Colour Deconfinement 3. J/Psi Production in Nuclear Collisions 4. Anomalous J/Psi Suppression 5. Outlook and Summary
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Publications and source records attributed to Helmut Satz.
1. Introduction 2. Charmomium Dissociation and Colour Deconfinement 3. J/Psi Production in Nuclear Collisions 4. Anomalous J/Psi Suppression 5. Outlook and Summary
Contents: 1. The Thermodynamics of Quarks and Gluons 2. Hard Probes: Colour Deconfinement 3. Electromagnetic Probes: Chiral Symmetry Restoration 4. Soft Probes: Equilibration and Expansion 5. Conclusions
We first introduce the conceptual basis of critical behaviour in strongly interacting matter, with colour deconfinement as QCD analog of the insulator-conductor transition and chiral symmetry restoration as special case of the associated shift in the mass of the constituents. Next we summarize quark-gluon plasma formation in finite temperature lattice QCD. We consider the underlying symmetries and their spontaneous breaking/restoration in the transition, as well as the resulting changes in thermodynamic behaviour. Finally, we turn to the experimental study of strongly interacting matter by high energy nuclear collisions, using charmonium production to probe the confinement status of the produced primordial medium. Recent results from Pb-Pb collisions at CERN may provide first evidence for colour deconfinement.
We provide a method to test if hadrons produced in high energy heavy ion collisions were emitted at freeze-out from an equilibrium hadron gas. Our considerations are based on an ideal gas at fixed temperature $T_f$, baryon number density $n_B$, and vanishing total strangeness. The constituents of this gas are all hadron resonances up to a mass of 2 GeV; they are taken to decay according to the experimentally observed branching ratios. The ratios of the various resulting hadron production rates are tabulated as functions of $T_f$ and $n_B$. These tables can be used for the equilibration analysis of any heavy ion data; we illustrate this for some specific cases.