Off-diagonal correlators of conserved charges from lattice QCD and how to relate them to experiment

Abstract

Like fluctuations, non-diagonal correlators of conserved charges provide a tool for the study of chemical freeze-out in heavy ion collisions. They can be calculated in thermal equilibrium using lattice simulations, and be connected to moments of event-by-event net-particle multiplicity distributions. We calculate them from continuum extrapolated lattice simulations at ${\mu }_B=0$, and present a finite-${\mu }_B$ extrapolation, comparing two different methods. In order to relate the grand canonical observables to the experimentally available net-particle fluctuations and correlations, we perform a Hadron Resonance Gas (HRG) model analysis, which allows us to completely break down the contributions from different hadrons. We then construct suitable hadronic proxies for fluctuations ratios, and study their behavior at finite chemical potentials. We also study the effect of introducing acceptance cuts, and argue that the small dependence of certain ratios on the latter allows for a direct comparison with lattice QCD results, provided that the same cuts are applied to all hadronic species. Finally, we perform a comparison for the constructed quantities for experimentally available measurements from the STAR Collaboration. Thus, we estimate the chemical freeze-out temperature to 165 MeV using a strangeness-related proxy. This is a rather high temperature for the use of the Hadron Resonance Gas, thus, further lattice studies are necessary to provide first principle results at intermediate ${\mu }_B$.

20 pages, 17 figures, 1 table, version published in Phys.Rev.D

References in corpus (14)

• The order of the quantum chromodynamics transition predicted by the standard model of particle physics
• The QCD transition temperature: results with physical masses in the continuum limit II.
• The QCD Equation of State to $\mathcal{O}({\mu }_B^6)$ from Lattice QCD
• High-precision scale setting in lattice QCD
• Freeze-out Conditions in Heavy Ion Collisions from QCD Thermodynamics
• QCD at finite chemical potential with six time slices
• The phase boundary for the chiral transition in (2+1)-flavor QCD at small values of the chemical potential
• Freeze-out conditions from net-proton and net-charge fluctuations at RHIC
• Freeze-out parameters from electric charge and baryon number fluctuations: is there consistency?
• Repulsive baryonic interactions and lattice QCD observables at imaginary chemical potential
• Chemical freeze-out in ultra-relativistic heavy ion collisions at sqrt(s)_NN = 130 and 200 GeV
• Multiplicity Fluctuations in Hadron-Resonance Gas
• Fast Equilibration of Hadrons in an Expanding Fireball
• Scaling properties at freeze-out in relativistic heavy ion collisions

Cited by in corpus (29)

• Lattice QCD equation of state at finite chemical potential from an alternative expansion scheme
• Hot and dense quark-gluon plasma thermodynamics from holographic black holes
• Theoretical and Experimental Constraints for the Equation of State of Dense and Hot Matter
• Second order cumulants of conserved charge fluctuations revisited I. Vanishing chemical potentials
• Search for the QCD Critical Point in High Energy Nuclear Collisions
• New approach to lattice QCD at finite density; results for the critical end point on coarse lattices
• Particlization of an interacting hadron resonance gas with global conservation laws for event-by-event fluctuations in heavy-ion collisions
• Lattice simulations of the QCD chiral transition at real baryon density
• Critical lensing and kurtosis near a critical point in the QCD phase diagram in and out-of-equilibrium
• Structure in the speed of sound: from neutron stars to heavy-ion collisions
• Baryon electric charge correlation as a magnetometer of QCD
• Equation of state of a hot-and-dense quark gluon plasma: lattice simulations at real ${\mu }_B$ vs. extrapolations
• Building a testable shear viscosity across the QCD phase diagram
• System Size and Flavour Dependence of Chemical Freeze-out Temperatures in ALICE Data from pp, pPb and PbPb Collisions at LHC Energies
• Localization properties of Dirac modes at the Roberge-Weiss phase transition
• Magnetic field effect on hadron yield ratios and fluctuations in a hadron resonance gas
• Chiral condensate and the equation of state at nonzero baryon density from the hadron resonance gas model with a repulsive mean field
• The BEST framework for the search for the QCD critical point and the chiral magnetic effect
• Efficiency corrections for mutually inclusive variables and particle identification effect for mixed-cumulants in heavy-ion collisions
• Conserved charge fluctuations at vanishing net-baryon density from Lattice QCD
• Cumulants of conserved charges in hydrodynamic simulations
• Constraining the hadronic spectrum and repulsive interactions in a hadron resonance gas via fluctuations of conserved charges
• Corrections to the hadron resonance gas from lattice QCD and their effect on fluctuation-ratios at finite density
• Ratio of baryon and electric-charge cumulants at second order with acceptance corrections
• Measurement of correlations among net-charge, net-proton, and net-kaon multiplicity distributions in Pb$-$Pb collisions at $\sqrt{s_{\text{NN}}}=5.02$ TeV
• Resummed lattice QCD equation of state at finite baryon density: strangeness neutrality and beyond
• From lattice to observables: Real and virtual experiments for exploring hot and dense QCD
• Viscous Gubser flow with conserved charges to benchmark fluid simulations
• Smooth matching of $\hat{q}$ from hadronic to quark and gluon degrees of freedom