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

2020 ◽  
Vol 229 (22-23) ◽  
pp. 3517-3536
Author(s):  
D. Blaschke ◽  
A. V. Friesen ◽  
Yu. L. Kalinovsky ◽  
A. Radzhabov
Keyword(s):  
Chemical Potential ◽  
Pion Mass ◽  
Heavy Ion ◽  
Bose Condensation ◽  
Chiral Phase ◽  
Qcd Phase Diagram ◽  
Scattering States ◽  
Meson Pole ◽  
Quark Models ◽  
Ion Collision

AbstractWithin 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 μB. 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 − μB plane as a proxy for the chemical freezeout line, whereby the variable x = T∕μB 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+∕π+ ratio is explained by the enhanced pion production at energies above √sNN=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.

scholarly journals Hadron Resonance Gas EoS and the Fluidity of Matter Produced in HIC

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Guruprasad Kadam ◽  
Swapnali Pawar
Keyword(s):  
Mass Spectrum ◽  
Chemical Potential ◽  
Heavy Ion ◽  
Baryon Chemical Potential ◽  
Hadron Mass ◽  
Lattice Quantum ◽  
Hadron Gas ◽  
Ion Collision ◽  
Discrete Mass ◽  
The Ideal

We study the equation of state (EoS) of hot and dense hadron gas by incorporating the excluded volume corrections into the ideal hadron resonance gas (HRG) model. The total hadron mass spectrum of the model is the sum of the discrete mass spectrum consisting of all the experimentally known hadrons and the exponentially rising continuous Hagedorn states. We confront the EoS of the model with lattice quantum chromodynamics (LQCD) results at finite baryon chemical potential. We find that this modified HRG model reproduces the LQCD results up to T=160 MeV at zero as well as finite baryon chemical potential. We further estimate the shear viscosity within the ambit of this model in the context of heavy-ion collision experiments.

Thermodynamic properties of light mesons and phase transition in an extended SU(2) NJL model

2019 ◽  
Vol 34 (13) ◽  
pp. 1950070
Author(s):  
J. R. Morones Ibarra ◽  
A. J. Garza Aguirre ◽  
Francisco V. Flores-Baez
Keyword(s):  
Chemical Potential ◽  
Pion Mass ◽  
Quark Condensate ◽  
The Other ◽  
Chiral Symmetry Restoration ◽  
Chiral Phase ◽  
Potential Dependence ◽  
Njl Model ◽  
The Masses ◽  
Sigma Meson

In this work, we study the temperature and chemical potential dependence of the masses of sigma and pion mesons as well as the quark condensate by using a SU(2) flavor version of the Nambu–Jona–Lassino model, introducing a prescription that mimics confinement. We have found that as the temperature increases, the mass of sigma shifts down, while the pion mass remains almost constant. On the other hand, the quark condensate decreases as the temperature and chemical potential increases. We have also analyzed the temperature and chemical potential dependence of the spectral function of the sigma meson, from which we observe at low values of T and [Formula: see text] an absence of a peak. Furthermore, as the Mott temperature is reached, its value increases abruptly and a distinct peak emerges, which is related with the dissociation of the sigma. For the case of [Formula: see text], the Mott dissociation is exhibited about the temperature of 189 MeV. We have also obtained the chiral phase diagram and the meson dissociation for different values of [Formula: see text]. From these results, we can state a relation between chiral symmetry restoration and Mott dissociation.

scholarly journals Finite-volume effects on phase transition in the Polyakov-loop extended Nambu–Jona-Lasinio model with a chiral chemical potential

2017 ◽  
Vol 32 (13) ◽  
pp. 1750067 ◽  
Author(s):  
Zan Pan ◽  
Zhu-Fang Cui ◽  
Chao-Hsi Chang ◽  
Hong-Shi Zong
Keyword(s):  
Finite Volume ◽  
Chemical Potential ◽  
System Size ◽  
Heavy Ion ◽  
Polyakov Loop ◽  
End Point ◽  
Chemical Potentials ◽  
Ion Collision ◽  
Quark Flavors ◽  
Volume Effects

To investigate the finite-volume effects on the chiral symmetry restoration and the deconfinement transition for a quantum chromodynamics (QCD) system with [Formula: see text] (two quark flavors), we apply the Polyakov-loop extended Nambu–Jona-Lasinio model by introducing a chiral chemical potential [Formula: see text] artificially. The final numerical results indicate that the introduced chiral chemical potential does not change the critical exponents, but shifts the location of critical end point (CEP) significantly; the ratios for the chiral chemical potentials and temperatures at CEP, [Formula: see text] and [Formula: see text], are significantly affected by the system size [Formula: see text]. The behavior is that [Formula: see text] increases slowly with [Formula: see text] when [Formula: see text] is “large” and [Formula: see text] decreases first and then increases with [Formula: see text] when [Formula: see text] is “small.” It is also found that for a fixed [Formula: see text], there is a [Formula: see text], where the critical end point vanishes and the whole phase diagram becomes a crossover when [Formula: see text]. Therefore, we suggest that for the heavy-ion collision experiments, which is to study the possible location of CEP, the finite-volume behavior should be taken into account.

scholarly journals Effects of Superstatistics on the Location of the Effective QCD Critical End Point

2019 ◽  
Vol 64 (8) ◽  
pp. 665
Author(s):  
A. Ayala ◽  
M. Hentschinski ◽  
L. A. Hernández ◽  
M. Loewe ◽  
R. Zamora
Keyword(s):  
Phase Diagram ◽  
Chemical Potential ◽  
Heavy Ion ◽  
Relativistic Heavy Ion Collisions ◽  
Chiral Symmetry Restoration ◽  
Interaction Volume ◽  
Qcd Phase Diagram ◽  
End Point ◽  
Ion Collisions ◽  
Effective Description

Effects of the partial thermalization during the chiral symmetry restoration at the finite temperature and quark chemical potential are considered for the position of the critical end point in an effective description of the QCD phase diagram. We find that these effects cause the critical end point to be displaced toward larger values of the temperature and lower values of the quark chemical potential, as compared to the case where the system can be regarded as completely thermalized. These effects may be important for relativistic heavy ion collisions, where the number of subsystems making up the whole interaction volume can be linked to the finite number of participants in the reaction.

scholarly journals A Study of the Properties of the QCD Phase Diagram in High-Energy Nuclear Collisions

Particles ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 278-307 ◽  
Author(s):  
Xiaofeng Luo ◽  
Shusu Shi ◽  
Nu Xu ◽  
Yifei Zhang
Keyword(s):  
Heavy Ion ◽  
High Energy ◽  
Baryon Density ◽  
Heavy Flavor ◽  
Relativistic Heavy Ion Collider ◽  
Density Region ◽  
Nuclear Collisions ◽  
Qcd Phase Diagram ◽  
Beam Energy Scan ◽  
Ion Collision

With the aim of understanding the phase structure of nuclear matter created in high-energy nuclear collisions at finite baryon density, a beam energy scan program has been carried out at Relativistic Heavy Ion Collider (RHIC). In this mini-review, most recent experimental results on collectivity, criticality and heavy flavor productions will be discussed. The goal here is to establish the connection between current available data and future heavy-ion collision experiments in a high baryon density region.

NJL model with the modified quark-dependent coupling strength G

2017 ◽  
Vol 32 (20) ◽  
pp. 1750107 ◽  
Author(s):  
Zhou-You Fan ◽  
Wen-Kai Fan ◽  
Qing-Wu Wang ◽  
Hong-Shi Zong
Keyword(s):  
Coupling Strength ◽  
Finite Temperature ◽  
Chemical Potential ◽  
Chiral Limit ◽  
Pion Mass ◽  
Quark Condensate ◽  
Qcd Phase Diagram ◽  
Njl Model ◽  
Lattice Quantum ◽  
Current Quark

In this paper, the coupling strength G of the Nambu–Jona-Lasinio (NJL) model is modified by incorporating quark’s feedback into the gluon propagator. The modified two-flavor NJL model with the quark-dependent coupling strength is explored. The quark condensate in this framework has a conspicuous agreement with the lattice quantum chromodynamics (QCD) results at finite temperature. Then, it is compared with the original NJL model in both zero (chiral limit) and nonzero current quark mass. The QCD phase diagram and susceptibilities are investigated in the temperature–chemical potential [Formula: see text] plane. Therefore, the pseudo-critical temperature [Formula: see text] and the critical end point (CEP) are worked out and compared with original NJL model or lattice QCD results. In addition, the pion mass and decay constant are studied at finite temperature.

scholarly journals Fluctuations of conserved charges from imaginary chemical potential

2018 ◽  
Vol 175 ◽  
pp. 07036
Author(s):  
Jana N. Guenther ◽  
Szabolcs Borsányi ◽  
Zoltan Fodor ◽  
Sandor D. Katz ◽  
Attila Pásztor ◽  
...  
Keyword(s):  
Experimental Data ◽  
Chemical Potential ◽  
Heavy Ion ◽  
Higher Order ◽  
Order Derivative ◽  
Heavy Ion Collision ◽  
Lattice Calculation ◽  
Eighth Order ◽  
Conserved Charges ◽  
Ion Collision

When comparing lattice calculation to experimental data from heavy ion collision experiments, the higher order fluctuations of conserved charges are important observables. An efficient way to study these fluctuations is to determine them from simulations at imaginary chemical potential. In this talk we present results up to the six order derivative in μB (with up to eighth order included in the fit), calculated on a 483 × 12 lattice with staggered fermions using different values of μB while μS = μQ = 0.

Free energy of a baryon at finite temperatures and its implications to the heavy-ion collisions

2015 ◽  
Vol 30 (26) ◽  
pp. 1550130
Author(s):  
Minati Biswal ◽  
Sanatan Digal ◽  
P. S. Saumia
Keyword(s):  
Free Energy ◽  
Transition Temperature ◽  
Chemical Potential ◽  
Canonical Formalism ◽  
Heavy Ion ◽  
Polyakov Loop ◽  
Heavy Ion Collision ◽  
Hydrodynamic Simulations ◽  
Ion Collisions ◽  
Ion Collision

We study the free energy per baryon using canonical formalism in the Polyakov loop Nambu–Jona-Lasinio model with imaginary chemical potential. We find that the free energy decreases rapidly with temperature around the transition temperature. This result coupled with the heavy-ion collision geometry leads to the creation of a free energy well for the baryons. We study the time evolution of this free energy well using hydrodynamic simulations and discuss the implications of this free energy well on the dynamics of the baryons.

scholarly journals CHIRALLY SYMMETRIC BUT CONFINED HADRONS AT FINITE DENSITY

2008 ◽  
Vol 23 (27n30) ◽  
pp. 2385-2388 ◽  
Author(s):  
L. YA. GLOZMAN ◽  
R. F. WAGENBRUNN
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Low Temperature ◽  
Quark Matter ◽  
Chemical Potential ◽  
Heavy Ion ◽  
Finite Density ◽  
Qcd Phase Diagram

At a critical finite chemical potential and low temperature QCD undergoes the chiral restoration phase transition. The folklore tradition is that simultaneously hadrons are deconfined and there appears the quark matter. We demonstrate that it is possible to have confined but chirally symmetric hadrons at a finite chemical potential and hence beyond the chiral restoration point at a finite chemical potential and low temperature there could exist a chirally symmetric matter consisting of chirally symmetric but confined hadrons. If it does happen in QCD, then the QCD phase diagram should be reconsidered with obvious implications for heavy ion programs and astrophysics.

scholarly journals Exploring hot and dense QCD matter with HADES

2020 ◽  
Vol 1643 (1) ◽  
pp. 012012
Author(s):  
Georgy Kornakov
Keyword(s):  
Chemical Potential ◽  
Thermal Emission ◽  
Heavy Ion ◽  
Nucleon Nucleon ◽  
Baryon Chemical Potential ◽  
Qcd Phase Diagram ◽  
Test Models ◽  
Particle Spectra ◽  
Strangeness Content ◽  
Dilepton Spectrum

Abstract Experiments at snn s NN = 2 − 3 3 GeV provide the lowest energy point of the global effort made by the heavy-ion community in order to map the QCD phase diagram. This correspond to the highest baryon chemical potential, 700-900 MeV according to the universal freeze-out curve, and temperatures of the fireball of 60-80 MeV. The formed matter can be characterized in terms of particle spectra, fluctuations and correlations. The dilepton spectrum is dominated by thermal emission from the medium and it is sensitive to in medium hadron properties. Strangeness production occurs below the free nucleon-nucleon threshold and it is a sensitive probe to test models of strangeness propagation in matter and its coupling to baryons. Data show a common scaling of measured yields as a function of number of participating nucleons independently on the strangeness content or mass of the hadron. Strangeness propagation in cold nuclear matter produced in pion induced reactions on heavy and light targets shows a significant absorption of negative kaons in heavy targets as well as a similar behaviour of ϕ indicating a strong coupling of ϕ with nucleons. Two-pion correlations, flow harmonics, fluctuations are explored as well in order to further pin down the properties of the created matter.

Sign in / Sign up

Export Citation Format

Share Document