In-Medium Nucleon-Nucleon Cross Section

Within the framework of Brueckner-Hartree-Fock method, the in-medium nucleonnucleon (NN) cross section is calculated. We base our investigation on a separable Paris potential for the NN interaction and a continuous choice for the single particle spectrum. It is found that the in-medium cross section is strongly modified by medium effect. In particular, with increasing of nuclear density, the cross sections decrease. This indicates a proper treatment of the density dependence of the in-medium NN cross sections is important.