摘要
We calculated the degree of isospin fractionation (N/Z)n/(N/Z)Nfrag by using the isospin dependent quantum molecular dynamics model (IQMD), where (N/Z)n and (N/Z)Nfrag are the saturated neutron to proton ratio of nucleon emissions and that of the fragment emissions respectively. In general, the observable in nuclear reaction is very sensitive to impact parameter. So it is interesting to investigate the dependence of (N/Z)n/(N/Z)Nfrag on the impact parameter b. Fig.1 shows the value of (N/Z)n/(N/Z)Nfrag as a function of impact parameter b for four different cases:
