Freeze-out parameters: lattice meets experiment

TL;DR

This paper uses lattice QCD calculations of higher order charge fluctuations to determine the freeze-out parameters in heavy-ion collisions, comparing results with experimental data to validate the approach.

Contribution

It provides first-principles lattice QCD results for fluctuation ratios to extract freeze-out conditions, connecting theory with experiment.

Findings

Lattice results for electric charge fluctuation ratios as functions of temperature.

Comparison with STAR data to estimate freeze-out temperature and chemical potential.

Continuum-extrapolated baryon number fluctuation ratios for future experimental validation.

Abstract

We present our results for ratios of higher order fluctuations of electric charge as functions of the temperature. These results are obtained in a system of 2+1 quark flavors at physical quark masses and continuum extrapolated. We compare them to preliminary data on higher order moments of the net electric charge distribution from the STAR collaboration. This allows us to determine the freeze-out temperature and chemical potential from first principles. We also show continuum-extrapolated results for ratios of higher order fluctuations of baryon number. These will allow to test the consistency of the approach, by comparing them to the corresponding experimental data (once they become available) and thus extracting the freeze-out parameters in an independent way.