Chiral Symmetry transition in the Linear Sigma Model with quarks: Counting effective QCD degrees of freedom from low to high temperature

Abstract

We use the linear sigma model coupled to quarks, together with a plausible location of the critical end point (CEP), to study the chiral symmetry transition in the QCD phase diagram. We compute the effective potential at finite temperature and density up to the contribution of the ring diagrams, both in the low and high temperature limits, and use it to compute the pressure and the position of the CEP. In the high temperature regime, by comparing to results from extrapolated lattice data, we determine the model coupling constants. Demanding that the CEP remains in the same location when described in the high temperature limit, we determine again the couplings and the pressure for the low temperature regime. We show that this procedure gives an average description of the lattice QCD results for the pressure and that the change from the low to the high temperature domains in this quantity can be attributed to the change in the coupling constants which in turn we link to the change in the effective degrees of freedom.

Title changed, accepted for publication in International Journal of Modern Physics A

References in corpus (13)

• The order of the quantum chromodynamics transition predicted by the standard model of particle physics
• The Phase Structure of the Polyakov--Quark-Meson Model
• Phase diagram and critical endpoint for strongly-interacting quarks
• 2+1 Flavor Polyakov--Nambu--Jona-Lasinio Model at Finite Temperature and Nonzero Chemical Potential
• Propagators and phase structure of Nf=2 and Nf=2+1 QCD
• Chiral crossover, deconfinement and quarkyonic matter within a Nambu-Jona Lasinio model with the Polyakov loop
• Finite density QCD with a canonical approach
• Inverse magnetic catalysis in the linear sigma model with quarks
• Thermodynamics and critical behavior in the Nambu-Jona-Lasinio model of QCD
• Chiral phase transition in the presence of spinodal decomposition
• The magnetized effective QCD phase diagram
• Influence of the isospin and hypercharge chemical potentials on the location of the CEP in the mu_B-T phase diagram of the SU(3)_L x SU(3)_R chiral quark model
• Thermodynamics of two-flavor lattice QCD with an improved Wilson quark action at non-zero temperature and density

Cited by in corpus (5)

• Neutral pion mass in the linear sigma model coupled to quarks at arbitrary magnetic field
• On the critical end point in a two-flavor linear sigma model coupled to quarks
• Collision energy dependence of the critical end point from baryon number fluctuations in the Linear Sigma Model with quarks
• Volume effects on the QCD critical end point from thermal fluctuations within the super statistics framework
• Locating the critical end point using the linear sigma model coupled to quarks