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.

Medium effect of nucleon-nucleon cross section on the isoscaling parameter α;

The interaction between nucleon and Ti meson is calculated with a good result according to equivalent field theory,which is helpful for the us age of interaction picture.

Within the framework of the relativistic Dirac Brueckner approach,the paper constructs two one boson exchange(OBE) interactions,one for nucleons only,the other including Δ degrees of freedom,calculates all t matrices and Δ self energy in the (N,N) and ( N,Δ ) systems in the full momentum spin space,and obtains better results.

In the paper, the isospin agular momentun coupling wave functions of nucleons are constructed by twice unitary transformations between group chains in agular momentun coupling space of neutron proton, the CFPs are factorized as products of three isoscalar factors(ISF) and the ISFs are calculated by using the coupling wave functions.