What we have learned so far from 3-fluid hydrodynamics

TL;DR

This paper analyzes heavy-ion collision data using a 3-fluid hydrodynamic model to evaluate its ability to reproduce experimental results and explore indications of quark-gluon phase transition.

Contribution

It assesses the effectiveness of a 3-fluid hydrodynamic model in describing heavy-ion collision data and discusses implications for phase transition signals.

Findings

The model successfully reproduces transverse-mass spectra of various hadrons.

Simultaneous fit of inverse-slope parameters suggests a common hydrodynamic flow.

Data may not necessarily indicate a phase transition but could reflect collective flow effects.

Abstract

Available data on heavy-ion collisions at AGS and SPS energies are analyzed using a 3-fluid dynamical model within a purely hadronic scenario. We investigate the problems met in reproducing these data within this scheme. In particular, we try to indicate those data which could point towards the occurrence of a phase transition into the quark-gluon phase. We also discuss the success of the model in reproducing the transverse-mass spectra of various hadrons. We argue that the simultaneous reproduction of the inverse-slope parameters of all considered particles may imply that these particles belong to the same hydrodynamic flow at the instant of their freeze-out rather than that it signals the onset of a phase transition.