Recent Results of the Hadron Resonance Gas Model and the Chemical Freeze-out of Strange Hadrons

TL;DR

This paper reviews recent advances in the hadron resonance gas model, highlighting phenomena like separate freeze-out of strange particles and the emergence of heavy resonances, to inform upcoming heavy-ion collision experiments.

Contribution

It introduces new insights into the chemical freeze-out process and the potential appearance of heavy resonances in thermal medium at specific collision energies.

Findings

Identification of separate chemical freeze-out for strange particles

Prediction of narrow heavy resonances above 2.5 GeV at 4-8 GeV collision energy

Discussion of resonance enhancement effects in thermal medium

Abstract

A detailed discussion of recent results obtained within the hadron resonance gas model with the multi-component hard core repulsion is presented. Among them there are the adiabatic chemical freeze-out criterion, the concept of separate chemical freeze-out of strange particles and the effects of enhancement and sharpening of wide resonances and quark gluon bags occurring in a thermal medium. These findings are discussed in order to strengthen the planned heavy-ion collision experimental programs at low collision energies. We argue, that due to found effects, at the center of mass collision energy 4-8 GeV the quark gluon bags may appear directly or in decays as new heavy resonances with the narrow width of about 50-150 MeV and with the mass above 2.5 GeV.