Constraining the symmetry energy with heavy-ion collisions and Bayesian analyses

Efficiency corrected single ratios of neutron and proton spectra in central Sn-112 + Sn-112 and Sn-124 + Sn-124 collisions at 120 MeV/u are combined with double ratios to provide constraints on the density and momentum dependencies of the isovector mean-field potential. Bayesian analyses of these data reveal that the isoscalar and isovector nucleon effective masses, m(s)* - m(v)* are strongly correlated. The linear correlation observed in m(s)* - m(v)* yields a nearly independent constraint on the effective mass splitting Delta m(np)* = (m(n)* - m(p)*)/m(N) = -0.05(-0.09)(+0.09)delta. The correlated constraint on the standard symmetry energy, S-0 and the slope, L at saturation density yields the values of symmetry energy S(rho(s) ) = 16.8(-1.2)(+1.2) MeV at a sensitive density of rho(s)/rho(0) = 0.43(-0.05)(+0.05). (C) 2019 The Authors. Published by Elsevier B.V.