Chemical freeze-out parametrization with mean field repulsive hadron resonance gas model

TL;DR

This paper models the chemical freeze-out surface in heavy-ion collisions using an interacting hadron resonance gas model with mean-field repulsive interactions, fitting data across multiple collider energies.

Contribution

It introduces phenomenological parameters for meson and baryon repulsion in the freeze-out parametrization, improving data fit without significantly altering key parameters.

Findings

Repulsive interactions improve fit quality.

Temperature and chemical potentials remain stable.

Parameters K_M and K_B are essential for better modeling.

Abstract

We have examined the chemical freeze-out surface of the heavy-ion collision experiments within an interacting hadron resonance gas model. By considering repulsive interaction among hadrons in the mean-field level, we have suitably parameterized the freeze-out surface by fitting the yield data of mid-rapidity for the most central collision, for the collision energy available in AGS, RHIC (BES), and LHC programs. To suitably account for the repulsive interaction among mesons and (anti-) baryons, we have introduced phenomenological parameters $K_M$ and $K_B$ in the freeze-out parametrization. Although a finite value of these two parameters seem to be necessary to have an improved normalized \emph{chi-square}, the effect on the rest of the parameters like temperature and relevant chemical potentials seem to be within the standard variance.