Hadron-Resonance Gas at Freeze-out: Reminder on Importance of Repulsive Interactions

TL;DR

This paper emphasizes the significance of repulsive interactions in the hadron-resonance gas model, showing their impact on matter properties at freeze-out in high-energy nuclear collisions.

Contribution

It demonstrates how repulsive interactions affect the chemical freeze-out conditions and the transition between baryon and meson dominated matter.

Findings

Repulsive interactions decrease the collision energy for maximum net-baryon density.

The transition point from baryon to meson dominance depends on the difference in hard-core radii.

Repulsive interactions significantly influence matter properties at relativistic energies.

Abstract

An influence of the repulsive interactions on matter properties is considered within the excluded volume van der Waals hadron-resonance gas model. Quantitative results are presented for matter at the chemical freeze-out in central nucleus-nucleus collisions at relativistic energies. In particular, it is shown that repulsive interactions connected to non-zero size of created particles lead to a significant decrease of collision energy at which the net-baryon density has a maximum. A position of the transition point from baryon to meson dominated matter depends on the difference between baryon and meson hard-core radiuses.