Local thermodynamical equilibrium and the equation of state of hot, dense matter created in Au + Au collisions at AGS


Journal Article

Local kinetic and chemical equilibration is studied for Au + Au collisions at 10.7 AGeV in the microscopic Ultrarelativistic Quantum Molecular Dynamics model (UrQMD). The UrQMD model exhibits dramatic derivations from equilibrium during the high density phase of the collision. Thermal and chemical equilibration of the hadronic matter seems to be established in the later stages during a quasi-isentropic expansion, observed in the central reaction cell with volume 125 fm3. For t ≥ 10 fm/c the hadron energy spectra in the cell are nicely reproduced by Boltzmann distributions with a common rapidly dropping temperature. Hadron yields change drastically and at the late expansion stage follow closely those of an ideal gas statistical model. The equation of state seems to be simple at late times: P ≅ 0.12ε. The time evolution of other thermodynamical variables in the cell is also presented. © 1998 Elsevier Science B.V. All rights reserved.

Full Text

Duke Authors

Cited Authors

  • Bravina, LV; Gorenstein, MI; Belkacem, M; Bass, SA; Bleicher, M; Brandstetter, M; Hofmann, M; Soff, S; Spieles, C; Weber, H; Stöcker, H; Greiner, W

Published Date

  • August 27, 1998

Published In

Volume / Issue

  • 434 / 3-4

Start / End Page

  • 379 - 387

International Standard Serial Number (ISSN)

  • 0370-2693

Digital Object Identifier (DOI)

  • 10.1016/S0370-2693(98)00624-8

Citation Source

  • Scopus