Probing the density dependence of the symmetry energy via multifragmentation at subsaturation densities

Abstract

Symmetry energy for asymmetric nuclear matter at subsaturation densities was investigated in the framework of an isospin-dependent quantum molecular dynamics model. A single ratio of neutrons and protons is compared with the experimental data of Famiano et al. [Phys. Rev. Lett. 97, 052701 (2006)] We have also performed a comparison for the double ratio with experimental as well as different theoretical results of Boltzmann-Uehling-Uhlenbeck in 1997, Isospin-dependent Boltzmann-Uehling-Uhlenbeck in 2004, Boltzmann-Nordeim-Vlasov, and Improved Quantum Molecular Dynamics models. It is found that the double ratio predicts the softness of symmetry energy, which is a little underestimated in the single ratio. Furthermore, the study of the single ratio is extended for different kinds of fragments, while the double ratio is extended for different neutron-rich isotopes of Sn.