Phase transition from hadronic matter to quark matter

We study the phase transition from two-flavor nuclear matter to quark matter. A mean field model, constructed at the quark level, is used to give the equation of state for nuclear matter, while the equation of state for color superconducting quark matter is calculated within the NJL model. It is found that at low temperature, the phase transition from nuclear to color superconducting quark matter will take place when the density is of order 2.5ρ0-5ρ0. At zero density, the quark phase will appear when the temperature is larger than about 148 MeV. Within the mean field treatment, the phase transition from nuclear matter to quark matter is always first order, whereas the transition between color superconducting quark matter and normal quark matter is second order