Isospin effects on the light particles in intermediate energy heavy ion collisions

Within the framework of an isospin-dependent quantum molecular dynamics (IQ MD) model,the emission features of light particles in Sn-112 + Sn-112 and S n-124 + Sn-124 are investigated at different beam energy,different impact p arameter,different EOS and different nucleon-nucleon cross section. Calcula tions show that the ratios of light particles are consistent with the syste matics of entrance channel isospin and the midrapidity region can emit more neutron-rich particles than projectiles-like rapidity. In addition,it is f ound that the light particle ratio is sensitive to the nuclear EOS,but not to the nucleon-nucleon cross section,which makes it possible to extract the isospin-dependent EOS.