Chiral phase transition and kaon-to-pion ratios in the entanglement SU(3) PNJL model

Abstract

Within the three-flavor PNJL and EPNJL chiral quark models we have obtained pseudoscalar meson properties in quark matter at finite temperature $T$ and baryochemical potential ${\mu }_B$. We compare the meson pole (Breit-Wigner) approximation with the Beth-Uhlenbeck (BU) approach that takes into account the continuum of quark-antiquark scattering states when determining the partial densities of pions and kaons. We evaluate the kaon-to-pion ratios along the (pseudo-)critical line in the $T-{\mu }_B$ plane as a proxy for the chemical freezeout line, whereby the variable $x=T/{\mu }_B$ is introduced that corresponds to the conserved entropy per baryon as initial condition for the heavy-ion collision experiments. We present a comparison with the experimental pattern of kaon-to-pion ratios within the BU approach and using $x$-dependent pion and strange quark potentials. A sharp "horn" effect in the energy dependence $K^{+}/{\pi }^{+}$ ratio is explained by the enhanced pion production at energies above $\sqrt{s_{NN}}=8$ GeV, when the system enters the regime of meson dominance. This effect is in line with the enhancement of low-momentum pion spectra that is discussed as a precursor of the pion Bose condensation and entails the occurrence of a nonequilibrium pion chemical potential of the order of the pion mass. We elucidate that the horn effect is not related to the existence of a critical endpoint in the QCD phase diagram.

arXiv comment20 pages, 7 figures

References in corpus (59)

• Phases of QCD: lattice thermodynamics and a field theoretical model
• Hadron production in central nucleus-nucleus collisions at chemical freeze-out
• Decoding the phase structure of QCD via particle production at high energy
• Comparison of Chemical Freeze-Out Criteria in Heavy-Ion Collisions
• Chiral crossover in QCD at zero and non-zero chemical potentials
• Bulk Properties of the Medium Produced in Relativistic Heavy-Ion Collisions from the Beam Energy Scan Program
• Energy Dependence of Pion and Kaon Production in Central Pb+Pb Collisions
• The Phase Structure of the Polyakov--Quark-Meson Model
• Phase diagrams in the three-flavor Nambu--Jona-Lasinio model with the Polyakov loop
• Thermal hadron production in relativistic nuclear collisions: the hadron mass spectrum, the horn, and the QCD phase transition
• The QCD crossover at finite chemical potential from lattice simulations
• Pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV: Evidence for the onset of deconfinement
• Hadronization in the SU(3) Nambu-Jona-Lasinio Model
• Hadron Production in Ultra-relativistic Nuclear Collisions: Quarkyonic Matter and a Triple Point in the Phase Diagram of QCD
• Chiral phase transition temperature in (2+1)-Flavor QCD
• Role of Vector Interaction and Axial Anomaly in the PNJL Modeling of the QCD Phase Diagram
• Entanglement between deconfinement transition and chiral symmetry restoration
• Quark Number Fluctuations in a Chiral Model at Finite Baryon Chemical Potential
• Transition from Baryonic to Mesonic Freeze-Out
• Nonlocal PNJL model beyond mean field and the QCD phase transition
• Chiral symmetry restoration in heavy-ion collisions at intermediate energies
• Nonlocal SU(3) chiral quark models at finite temperature: the role of the Polyakov loop
• The isentropic equation of state of 2-flavor QCD
• Analysis of U${}_A$(1) symmetry-breaking and restoration effects on the scalar-pseudoscalar spectrum
• Generalized Beth--Uhlenbeck approach to mesons and diquarks in hot, dense quark matter
• Finite T meson correlations and quark deconfinement
• Pseudoscalars Mesons in Hot, Dense Matter
• Meson properties at finite temperature in a three flavor nonlocal chiral quark model with Polyakov loop
• Explanation of hadron transverse-momentum spectra in heavy-ion collisions at sqrt(sNN) = 2.76 TeV within chemical non-equilibrium statistical hadronization model
• Phase diagram of neutral quark matter in nonlocal chiral quark models
• An effective gluon potential and hybrid approach to Yang-Mills thermodynamics
• Pi-Pi scattering lengths at finite temperature
• The Polyakov loop and the hadron resonance gas model
• 1/N_c- expansion of the quark condensate at finite temperature
• Towards a Unified Quark-Hadron Matter Equation of State for Applications in Astrophysics and Heavy-Ion Collisions
• D mesons at finite temperature and density in the PNJL model
• Width of the QCD transition in a Polyakov-loop DSE model
• Pion dissociation and Levinson's theorem in hot PNJL quark matter
• Chiral condensate in hadronic matter
• Mott dissociation of pions and kaons in hot, dense quark matter
• Strangeness production time and the K+/pi+ horn
• Determination of the strength of the vector-type four-quark interaction in the entanglement Polyakov-extended Nambu-Jona-Lasino model
• Quark-hadron phase transition in a three flavor PNJL model for interacting quarks
• Supporting the search for the CEP location with nonlocal PNJL models constrained by Lattice QCD
• Impact of the vector interaction on the phase structure of QCD matter
• The horn in the kaon to pion ratio
• Isentropic evolution of the matter in heavy-ion collisions and the search for the critical endpoint
• Effects of Model Parameters in Thermodynamics of the PNJL Model
• Proton-proton interactions and onset of deconfinement
• Effects of entanglement and instanton suppression at finite temperature in a SU(2) EPNJL model with anomaly
• Generalized Beth-Uhlenbeck approach to the equation of state for quark-hadron matter
• Brief history of the search for critical structures in heavy-ion collisions
• Strange matter and kaon to pion ratio in SU(3) PNJL model
• Transition from Baryon- to Meson-Dominated Freeze Out -- Early Decoupling around 30 A GeV?
• Quark scattering off quarks and hadrons
• Mott-Anderson freeze-out and the strange matter "horn"
• Effects of composite pions on the chiral condensate within the PNJL model at finite temperature
• Evidence for chiral symmetry restoration in heavy-ion collisions
• Emergence of soft quark excitations by the coupling with a soft mode of the QCD critical point

Cited by in corpus (2)

• Strangeness thermodynamic instabilities in hot and dense nuclear matter
• Mott dissociation and kaon to pion ratio in the EPNJL model