Role of repulsive interactions in the interplay with missing strange resonances

TL;DR

This paper investigates how repulsive and attractive interactions, modeled via excluded volume effects and resonance formation respectively, influence QCD thermodynamics, highlighting the importance of repulsive effects for accurate descriptions of lattice data and fluctuations.

Contribution

It demonstrates the significance of repulsive interactions modeled by excluded volume effects in conjunction with resonance formation for understanding QCD thermodynamics.

Findings

Excluded volume effects are present in lattice QCD thermodynamics.

Repulsive interactions are essential for describing higher order fluctuations.

Flavour dependent effective sizes are extracted from data.

Abstract

The standard implementation of the HRG model has been shown to be unable to describe all the available data on QCD matter. Here we show the balance of repulsive and attractive hadronic interactions on QCD thermodynamics through observables both calculated by lattice simulations and measured in experiment. Attractive interactions are mediated by resonance formation, which are here implemented through extra states predicted by the Quark Model, while repulsive interactions are modelled by means of Excluded Volume (EV) effects. Informations on flavour dependent effective sizes are extracted. It is found that EV effects are present in lattice QCD thermodynamics, and are essential for a comprehensive description of higher order fluctuations of conserved charges.