Equation of state for asymmetric nuclear matter with infinite-order   summation of ring diagrams
  The particle-particle hole-hole ring-diagram summation method is employed to obtain the equation of state of asymmetric nuclear matter over a wide range of asymmetry fraction. Compared with Brueckner Hartree-Fock and model-space Brueckner Hartree-Fock calculations, this approach gives a softer equation of state, increased symmetry energy and a lower value for the incompressibility modulus which agrees quite well with the values used in the hydrodynamical model for the supernovae explosion. 
J. Shamanna, T.T.S. Kuo, I. Bombaci, Subhankar Ray