Thermodynamics of quark quasi-particle ensemble

Full text: (author)The features of hot and dense gas of quarks which are considered as the quasi-particles of the model Hamiltonian with four-fermion interaction are studied. Being adapted to the Nambu-Jona-Lasinio model this approach allows to accommodate a phase transition similar to the nuclear liquid-gas one at the proper scale and to argue an existence of the mixed (inhomogeneous) phase of vacuum and normal baryonic matter as a plausible scenario of chiral symmetry (partial) restoration. Analyzing the transition layer between two phases it is estimated the surface tension coefficient and speculate on the possible existence of quark droplet