Fluctuations and Correlations in Nucleus-Nucleus Collisions within Transport Models

TL;DR

This paper reviews how microscopic transport models like HSD and UrQMD simulate particle fluctuations and correlations in nucleus-nucleus collisions, comparing results with experimental data and statistical models to explore signals of the QCD critical point.

Contribution

It provides a detailed comparison of transport model predictions with experimental data and statistical models, focusing on fluctuations and correlations relevant to the QCD critical point.

Findings

Transport models reproduce some experimental fluctuation patterns.

Centrality and acceptance significantly affect fluctuation observables.

Results offer insights into the QCD phase diagram and critical point signals.

Abstract

Particle number fluctuations and correlations in nucleus-nucleus collisions at SPS and RHIC energies are studied within microscopic transport approaches. In this review we focus on the Hadron-String-Dynamics (HSD) and Ultra-relativistic-Quantum-Molecular-Dynamics (UrQMD) models The obtained results are compared with the available experimental data as well as with the statistical models and the model of independent sources. In particular the role of the experimental centrality selection and acceptance is discussed in detail for a variety of experimental fluctuations and correlation observables with the aim to extract information on the critical point in the $(T,\mu_B)$ plane of strongly interacting matter.