Constraining the hadronic spectrum and repulsive interactions in a hadron resonance gas via fluctuations of conserved charges

Abstract

We simultaneously incorporate two common extensions of the hadron resonance gas model, namely the addition of extra, unconfirmed resonances to the particle list and the excluded volume repulsive interactions. We emphasize the complementary nature of these two extensions and identify combinations of conserved charge susceptibilities that allow to constrain them separately. In particular, ratios of second-order susceptibilities like ${\chi }_{11}^{BQ}/{\chi }_2^B$ and ${\chi }_{11}^{BS}/{\chi }_2^B$ are sensitive only to the baryon spectrum, while fourth-to-second order ratios like ${\chi }_4^B/{\chi }_2^B$, ${\chi }_{31}^{BS}/{\chi }_{11}^{BS}$, or ${\chi }_{31}^{BQ}/{\chi }_{11}^{BQ}$ are mainly determined by repulsive interactions. Analysis of the available lattice results suggests the presence of both the extra states in the baryon-strangeness sector and the repulsive baryonic interaction, with indications that hyperons have a smaller repulsive core than non-strange baryons. The modified hadron resonance gas model presented here significantly improves the description of lattice QCD susceptibilities at chemical freeze-out and can be used for the analysis of event-by-event fluctuations in heavy-ion collisions.

10 pages, 5 figures, version published in Phys. Rev. D

References in corpus (19)

• The order of the quantum chromodynamics transition predicted by the standard model of particle physics
• The equation of state in (2+1)-flavor QCD
• The QCD equation of state with dynamical quarks
• The QCD transition temperature: results with physical masses in the continuum limit
• The QCD Equation of State to $\mathcal{O}({\mu }_B^6)$ from Lattice QCD
• Mass spectra and Regge trajectories of light mesons in the relativistic quark model
• Freeze-out conditions from net-proton and net-charge fluctuations at RHIC
• Additional Strange Hadrons from QCD Thermodynamics and Strangeness Freeze-out in Heavy Ion Collisions
• Critical point in the phase diagram of primordial quark-gluon matter from black hole physics
• Freeze-out parameters from electric charge and baryon number fluctuations: is there consistency?
• Repulsive baryonic interactions and lattice QCD observables at imaginary chemical potential
• Skewness and kurtosis of net baryon-number distributions at small values of the baryon chemical potential
• Off-diagonal correlators of conserved charges from lattice QCD and how to relate them to experiment
• Hadron Resonance Gas Equation of State from Lattice QCD
• Multicomponent van der Waals equation of state: Applications in nuclear and hadronic physics
• New scenarios for hard-core interactions in a hadron resonance gas
• Particlization of an interacting hadron resonance gas with global conservation laws for event-by-event fluctuations in heavy-ion collisions
• Criticality in a Hadron Resonance Gas model with the van der Waals interaction
• Hadron resonance gas with van der Waals interactions