Strangelets formation in high energy heavy-ion collisions

The properties of a phase diagram of strange quark matter in equilibrium with hadronic matter at finite temperature are studied, where the quark phase and hadron phase are treated by a baryon density-dependent quark mass model and hadron resonance gas model with a hard core repulsion factor, respectively. The thermodynamic conditions for the formation of metastable strange quark droplets (``strangelets'') in relativistic nuclear collisions are discussed. We obtained a rich structure of the phase diagram at finite temperature, and study the dynamical trajectories of an expanding strange fireball. Our results indicate that the strangeness fraction fₛ, perturbation parameter C, and confinement parameter D have a strong influence on the properties of the phase diagram and the formation of strangelets. Considering the isentropic expansion process, we found that the initial entropy per baryon is less than or equal to 5, which gives a large probability for the formation of strangelets. Furthermore, a sufficiently large strangeness fraction fₛ and one-gluon-exchange interaction and sufficiently small confinement interaction create possibilities for the formation of strangelets. On the contrary, the fireball will always complete the hadronization process when fₛ=0 or C≥0 or D1/2≥170 MeV.