Influence of medium correction of nucleon-nucleon cross section on fragmentation

The influence of medium correction of isospin-dependent nucleon-nucleon (NN) cross section on fragmentation in heavy,ion collisions at intermediate energies is studied by using the isospin-dependent quantum molecular dynamical model. The results show that the medium correction of isospin-dependent nucleon-nucleon cross section enhances the sensitivity of the free nucleons emission and multiplicity of intermediate mass fragments on the isospin effects of NN cross section. The character of nuclear stopping that depends strongly on the isospin effect of NN cross section and weakly on the different forms of symmetry potential is not affected by the medium correction of NN cross section. And hence this charater of nuclear stopping stems mainly from the isospin effects of free nucleon-nucleon cross section.