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Excitation Function of Energy Density and Partonic Degrees of Freedom in Relativistic Heavy Ion Collisions

H. Weber·C. Ernst·M. Bleicher·L. Bravina·H. Stoecker·W. Greiner·C. Spieles·S. A. Bass
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Abstract

We estimate the energy density pile-up at mid-rapidity in central Pb+Pb collisions from 2 - 200 GeV/nucleon. The energy density is decomposed into hadronic and partonic contributions. A detailed analysis of the collision dynamics in the framework of a microscopic transport model shows the importance of partonic degrees of freedom and rescattering of leading (di)quarks in the early phase of the reaction for lab-energies > 30 GeV/nucleon. In Pb+Pb collisions at 160 GeV/nucleon the energy density reaches up to 4 GeV/fm^3, 95% of which are contained in partonic degrees of freedom.

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H. Weber, C. Ernst, M. Bleicher, L. Bravina, H. Stoecker, W. Greiner, C. Spieles, S. A. Bass. 1998-08-11. Excitation Function of Energy Density and Partonic Degrees of Freedom in Relativistic Heavy Ion Collisions. https://doi.org/10.1016/s0370-2693(98)01252-0

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