Liquid-gas mixed phase in nuclear matter at finite temperature

Maruyama, Toshiki  ; Tatsumi, Toshitaka*

Liquid-gas (LG) phase transition and the relevant equation of state (EOS) is one of the most important subjects in nuclear physics and astrophysics. In the crust region of compact stars or supernovae we can expect non-uniform matter with exotic shapes called pasta as a mixed phase during the liquid-gas phase transition. It is not only interesting theoretically but may affect the mechanical and thermodynamical properties of compact stars. We explore the geometrical structure of LG mixed phase by using relativistic mean-field model. To get the EOS of the system, the Maxwell construction is found to be applicable to symmetric nuclear matter, where protons and neutrons behave simultaneously. For asymmetric nuclear matter, on the other hand, the phase equilibrium is obtained by fully solving the Gibbs conditions since the components in the L and G phases are completely different. We also discuss the effects of surface and the Coulomb interaction on the mixed phase.