Isospin effect of neutron (proton) emission number in intermediate energy heavy ion collisions

Effects of the symmetry potential U-sym and the isospin dependence of in-medium nucleon-nucleon cross section N-n(N-p) on the number of neutron (proton) emitted as well as their dependence on the momentum dependent interaction (MDI) are studied within an isospin dependent Quantum Molecular Dynamics (IQMD) model. The isospin dependence nucleon-nucleon cross section is found to have a much stronger influence on the N-n(N-p) especially for the neutron-deficient collision system with MDI in the energy region from about 100 to 400MeV/nucleon. The calculation results are clear to show that the number of neutron (proton) emitted during reaction in the neutron-deficient system, depends sensitively on the isospin dependence of in-medium nucleon-nucleon cross section and weakly on the symmetry potential with MDI. In this case one can make use of the number of neutron (proton) emitted as a probe to extract simultaneously both the magnitude and the in-medium nucleon-nucleon cross section.