Bubble dynamics and the quark-hadron phase transition in nuclear collisions

Abstract

We study the nucleation of a quark gluon plasma (QGP) phase in a hadron gas at low temperatures and high baryon densities. This kind of process will presumably happen very often in nuclear collisions at FAIR and NICA. When the appropriate energy densities (or baryon densities) and temperatures are reached the conversion of one phase into another is not instantaneous. It is a complex process, which involves the nucleation of bubbles of the new phase. One important element of this transition process is the rate of growth of a QGP bubble. In order to estimate it we solve the Relativistic Rayleigh−Plesset equation which governs the dynamics of a relativistic spherical bubble in a strongly interacting medium. The baryon rich hadron gas is represented by the nonlinear Walecka model and the QGP is described by the MIT bag model and also by a mean field model of QCD.

Interface effects of strange quark matter

“…For the dynamic processes where the transition between SQM and hadronic matter takes place, the interface effects also play important roles. For example, it was shown that a larger σ inhibits quark matter nucleation during the deconfinement phase transitions in cold neutron stars [55,56], core-collapse supernova [57,58], and heavy-ion collisions [59,60]. Similarly, the interface effects are important for the hadronization phase transition in the early Universe [61,62,63,64].…”

Interface effects of strange quark matter with density dependent quark masses

“…The transition between SQM and HM is also sensitive to the interface effects. For the creation of SQM in neutron stars [46,47], core-collapse supernova [48,49], and heavy-ion collisions [50,51], it was show that the surface tension plays a crucial role, where larger σ disfavors or inhibits quark matter nucleation in HM. The survival of SQM objects in a heated environment is also sensitive to the value of σ, where SQM objects may not have survived the evaporation or boiling process in the early Universe [52][53][54][55].…”