title: Determination of the stiffness of the nuclear symmetry energy from isospin diffusion.
abstract: With an isospin- and momentum-dependent transport model, we find that the degree of isospin diffusion in heavy-ion collisions at intermediate energies is affected by both the stiffness of the nuclear symmetry energy and the momentum dependence of the nucleon potential. Using a momentum dependence derived from the Gogny effective interaction, recent experimental data from NSCL-MSU on isospin diffusion are shown to be consistent with a nuclear symmetry energy given by E(sym)(rho) approximately 31.6(rho/rho(0))(1.05) at subnormal densities. This leads to a significantly constrained value of about -550 MeV for the isospin-dependent part of the isobaric incompressibility of isospin asymmetric nuclear matter.
authors.affiliation: Cyclotron Institute and Physics Department, Texas A&M University, College Station, Texas 77843-3366, USA.
authors.forename: Lie-Wen
authors.initials: LW
authors.lastname: Chen
authors.forename: Che Ming
authors.initials: CM
authors.lastname: Ko
authors.forename: Bao-An
authors.initials: BA
authors.lastname: Li