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arXiv · hep-ph/0310263

Diffusion and local deconfinement in relativistic systems

Georg Wolschin
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Abstract

In relativistic systems at RHIC energies, new deconfinement signatures emerge and indicate an increasingly clear separation between soft hadronic processes, and hard partonic interactions in a locally deconfined subsystem. Here the emphasis is on longitudinal variables, namely, net-baryon rapidity distributions. As described in a Relativistic Diffusion Model, they change from bell-shaped at the lower to double-humped at the higher SPS-energy, but do not reach local statistical equilibrium. At sqrt(sNN) = 200 GeV in the Au-Au system, however, they are shown to consist of three components. In addition to the nonequilibrium contributions, a third fraction close to midrapidity containing Z_eq = 22 protons reaches local statistical equilibrium in a discontinuous transition. It may be associated with a deconfinement of the participant partons and thus, serve as a signature for Quark-Gluon Matter formation.

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Georg Wolschin. 2003-11-05. Diffusion and local deconfinement in relativistic systems. https://doi.org/10.1103/physrevc.69.024906

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