Abstract: There is a restriction to the solution of the epuation of θ (the ratio between the density of the nuclear matter and the density of the nuclear matter at saturation) in the J. Cooperstein's equ ation of state. Starting from the expression of nucleons pressure near the saturation density at zero temperature, a expression of nucleon internal energy is obtained by us. the re striction mentioned above in J. Cooperstein's equation of state has been removed by substituting the expression of nucleon internal energy obtained by us for the expression used by J.Cooperstein. Me present results of hydrodynamic cal culation of core collapse and subsequent shock wave formation and propagation using the equation of state of us and using the 15M_⊙ initial model of WZW.The relesse of gravitational binding energy of core can be increased by proper softening the equation of state above the sqturation density of nucl ear matter.

Key words: equation of state, supernova, explosion