A GENERALIZED EQUATION OF STATE FOR HOT, DENSE MATTER

An equation of state for hot, dense matter is presented in a form that is sufficiently rapid to use directly in hydrodynamical simulations, for example, in stellar collapse calculations. It contains an adjustable nuclear force that accurately models both potential and mean-field interactions, and it allows for the input of various nuclear parameters, some of which are not yet experimentally well-determined. These include the bulk incompressibility parameter, the bulk and surface symmetry energies, the symmetric matter surface tension, and the nucleon effective masses. This permits parametric studies of the equation of state in astrophysical situations. The equation of state is modelled after the Lattimer, Lamb, Pethick and Ravenhall LLPR compressible liquid-drop model for nuclei, and includes the effects of interactions and degeneracy of the nucleons outside nuclei. Account is also taken of nuclear deformations and the phase transitions from nuclei to uniform nuclear matter at subnuclear densities. Comparisons of this equation of state are made to the results of the LLPR model and the Cooperstein-Baron equation of state. The effects of varying the bulk incompressibility are also investigated.