Effect of the momentum dependence of the nuclear symmetry potential on the {pi}{sup -}/{pi}{sup +} ratio in heavy-ion collisions

In the framework of the isospin-dependent Boltzmann-Uehling-Uhlenbeck transport model, the effect of the momentum dependence of the nuclear symmetry potential on the {pi}{sup -}/{pi}{sup +} ratio in the neutron-rich reaction {sup 132}Sn +{sup 124}Sn at a beam energy of 400 MeV/nucleon is studied. We find that the momentum dependence of the nuclear symmetry potential affects the compressed density of colliding nuclei, the numbers of produced {pi}{sup -} and {pi}{sup +}, as well as the value of the {pi}{sup -}/{pi}{sup +} ratio. The momentum-dependent nuclear symmetry potential increases the compressed density of colliding nuclei, the number of produced resonances {Delta}(1232), N{sup *}(1440), {pi}{sup -}, and {pi}{sup +}, as well as the value of the {pi}{sup -}/{pi}{sup +} ratio.