Abstract
Local thermal and chemical equilibration is studied for central A+A collisions at 10.7–160 AGeV in the Ultrarelativistic Quantum Molecular Dynamics model (UrQMD). The UrQMD model exhibits strong deviations from local equilibrium at the high density hadron–string phase formed during the early stage of the collision. Equilibration of the hadron–resonance matter is established in the central cell of volume V=125 fm 3 at later stages, t≥10 fm/ c, of the resulting quasi-isentropic expansion. The thermodynamical functions in the cell and their time evolution are presented. Deviations of the UrQMD quasi-equilibrium state from the statistical mechanics equilibrium are found. They increase with energy per baryon and lead to a strong enhancement of the pion number density as compared to statistical mechanics estimates at SPS energies.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
