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تسجيل مستخدم جديدQuark-hadron phase transition in a three flavor PNJL model
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We study the quark-hadron phase transition by using a three flavor Nambu-Jona-Lasinio model with the Polyakov loop at zero chemical potential, extending our previous work with two flavor model. We show that the equation of state at low temperatures is dominated by pions and kaons as collective modes of quarks and anti-quarks. As temperature increases, mesonic collective modes melt into the continuum of quark and anti-quark so that hadronic phase changes continuously to the quark phase where quark excitations dominate pressure.
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We extend our previous study of the quark-hadron phase transition at finite temperatures with zero net baryon density by two flavor Nambu-Jona-Lasinio model with Polyakov loop to the three flavor case in a scheme which incorporates flavor nonet pseud
o scalar and scalar mesonic correlations on equal footing. The role of the axial U(1) breaking Kobayashi-Maskawa-t Hooft interaction on the low-lying thermal excitations is examined. At low temperatures, only mesonic correlations, mainly due to low mass mesonic collective excitations, pions and kaons, dominate the pressure while thermal excitations of quarks are suppressed by the Polyakov loop. As temperature increases, kaons and pions melt into the continuum of quark and anti-quark excitations successively so that hadronic phase changes continuously to the quark phase where quark excitations dominate pressure together with gluon pressure coming from the effective potential for the Polyakov loop. Since we introduce mesons as not elementary fields but auxiliary fields made from quarks, we can describe the phase transition between hadronic phase and quark phase in a unified fashion.
We study quark-hadron phase transition at finite temperature with zero net baryon density by the Nambu-Jona-Lasinio model for interacting quarks in uniform background temporal color gauge fields. At low temperatures, unphysical thermal quark-antiquar
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The two-Equation of State (Two-EoS) model is used to describe the hadron-quark phase transition in dense-hot matter formed in heavy-ion collisions. The non-linear Walecka model is used to describe the hadronic phase. For the quark phase, the Nambu--J
ona-Lasinio model coupled to Polyakov-Loop fields (PNJL) is used to include both the chiral and (de)confinement dynamics. The phase diagrams are derived from the Gibbs conditions and compared with the results obtained in the Hadron-NJL model without confinement. As in the Hadron-NJL case a first order transition is observed, but with a Critical-End-Point at much higher temperature, consequence of the confinement mechanism that reduces the degrees of freedom of the quark matter in proximity of the phase transition. Particular attention is devoted to the phase transition in isospin asymmetric matter. Interesting isospin effects are found at high baryon density and reduced temperatures, in fact common also to other quark models, like MIT-Bag and NJL model. Some possible observation signals are suggested to probe in Heavy-Ion Collision (HIC) experiments at intermediate energies.
We investigate the process of phase conversion in a thermally-driven {it weakly} first-order quark-hadron transition. This scenario is physically appealing even if the nature of this transition in equilibrium proves to be a smooth crossover for vanis
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