EPAX2 is an empirical parameterization relying on data mainly from target spallation and projectile fragmentation reactions at relativistic energies (>200 MeV/u). It has been used routinely to calculate secondary beam production rates in many radioactive ion beam facilities. 

However, some experimental results show that at intermediate energies (20-200 MeV/u) the fragmentation cross sections for fragments far from the stability line are over-estimated in EPAX2 calculations, and the target dependence of the cross section of the fragments far from the stability line fail to be reproduced by the EPAX2 calculations.  

Researchers at Institute of Modern Physics, Chinese Academy of Sciences (IMP,CAS） modified the EPAX2 parameterization for more accurately estimating the fragment cross sections at intermediate energies.  

The most improvement in the modified EPAX2 parameterization was that the influences of target isospin and projectile energy on cross sections were introduced. Compared to the experimental data, the modified EPAX2 could predict reliably the cross sections, and the target dependence of the fragment cross section could be reproduced for most reaction systems at intermediate energies. 

The results have been published in Nuclear Physics. A 915(2013) 59-69