Strange-quark matter within the Nambu-Jona-Lasinio model

The equation of state of baryon-rich quark matter is studied within the SU(3) Nambu-Jona-Lasinio model with flavor-mixing interaction. Possible bound states (strangelets) and chiral phase transitions in this matter are investigated at various values of the strangeness fraction r(delta) model predictions are very sensitive to the ratio of the vector and scalar coupling constants, xi = G(V)/G(S), At xi = 0.5 and zero temperature, the binding energy takes a maximum value of about 15 MeV per baryon at r(delta) similar or equal to 0.4. Such strangelets are negatively charged and have typical lifetimes of about 10(-7) s. Calculations are performed at finite temperatures as well. According to these calculations, bound states exist up to temperatures of about 15 MeV. The model predicts a first-order chiral phase transition at finite baryon densities. The parameters of this phase transition are calculated as functions of r(delta). (C) 2001 MAIK "Nauka/Interperiodica".