Particle production and chemical freezeout from the hybrid UrQMD approach at NICA energies

TL;DR

This paper uses the hybrid UrQMD model to analyze particle ratios across various energies, comparing results with experimental data and other models, and explores phase transition effects at NICA energies.

Contribution

It demonstrates the effectiveness of the hybrid UrQMD approach in reproducing experimental particle ratios and investigates phase transition signatures at low energies.

Findings

UrQMD agrees well with experimental data at RHIC-BES energies.

Particle ratios for different phase transition scenarios are nearly indistinguishable at low energies.

UrQMD can simulate particle ratios down to 3 GeV for upcoming NICA and FAIR experiments.

Abstract

The energy dependence of various particle ratios is calculated within the Ultra-Relativistic Quantum Molecular Dynamics approach and compared with the hadron resonance gas (HRG) model and measurements from various experiments, including RHIC-BES, SPS and AGS. It is found that the UrQMD particle ratios agree well with the experimental results at the RHIC-BES energies. Thus, we have utilized UrQMD in simulating particle ratios at other beam energies down to 3 GeV, which will be accessed at NICA and FAIR future facilities. We observe that the particle ratios for crossover and first-order phase transition, implemented in the hybrid UrQMD v3.4, are nearly indistinguishable, especially at low energies (at large baryon chemical potentials or high density).