Calculation of secondary neutron spectra from 2Â GeV electron-induced reactions using MARS15 code

The secondary neutron spectra from 2-GeV electron-induced reactions for various thicknesses of materials were calculated by using the MARS Monte-Carlo code to evaluate its applicability for shielding calculation of high-energy electron accelerator by comparing with experimental results. The results of the calculation in simplified geometry reproduce well the energy dependence of the experimental results. The agreement in magnitude between the experiment and the calculation is very good for thick targets and becomes worse on decreasing the target thickness. These results will be helpful for further improvements around 1 GeV in the photo-nuclear model of the CEM03 event generator used in MARS15; however, the effects of surrounding materials should be estimated.