Description of the first order phase transition region of an equation of state for QCD with a critical point*

The search for signatures of the possible critical point in the QCD phase diagram have been a major effort in the theory and experimental community in the last decades. Besides those features directly attributed to the critical point, evidence of its existence can also be found by searching for the first order phase transition line, i.e. evidence that it is no longer a crossover. In this equation of state, we map the full coexistence region of the first order phase transition from the 3D Ising model onto the QCD phase diagram. The scaling equation of state in the mean field approximation is mapped onto the phase diagram of strongly-interacting matter, based on the principle of universal behavior in the vicinity of a critical point. A thermodynamic description of the thermodynamically metastable and unstable states of matter is achieved beyond that of the Maxwell construction. This analytical approach then follows the true curves for the coexistence and spinodal lines in the phase diagram. We will discuss the features observed upon mapping the mean field Ising model onto the QCD phase diagram as well as the behavior of the pressure, density, and entropy describing the equation of state.