Novel determination of density, temperature, and symmetry energy for nuclear multifragmentation through primary fragment-yield reconstruction

For thefirst time primary hot isotope distributions are experimentally reconstructed in intermediate heavy-ion collisions and used with antisymmetrized molecular dynamics (AMD) calculations to determine density, temperature, and symmetry energy coefficient in a self-consistent manner. A kinematical focusing method is employed to reconstruct the primary hot fragment-yield distributions for multifragmentation events observed in the reaction system 64Zn+112Sn at 40 MeV/nucleon. The reconstructed yield distributions are in good agreement with the primary isotope distributions of AMD simulations. The experimentally extracted values of the symmetry energy coefficient relative to the temperature, asym/T, are compared with those of the AMD simulations with different density dependence of the symmetry energy term. The calculated asym/T values change according to the different interactions. By comparison of the experimental values of asym/T with those of calculations, the density of the source at fragment formation was determined to be ρ/ρ0=(0.63±0.03). Using this density, the symmetry energy coefficient and the temperature are determined in a self-consistent manner as asym=(24.7±1.9)MeV and T=(4.9±0.2) MeV.