Abstract

For the design of ADS (Accelerator Driven System), it is important to study neutron spectra and details of nuclear reactions induced by neutrons. Furthermore, neutron energy and angular distribution data are important for a correct simulation of the propagation of particles inside a spallation target and the geometrical distribution of the outgoing neutron flux. Many experimental results are available for thin targets and massive targets additional studies of neutron spectra and neutron production were investigated to design target for ADS with incident proton energies up to 3 GeV. In our study, the angular distribution and the neutron energy spectra are reported for the (p,n) reaction on target nuclei such as Pb, U, W with energy from 50 MeV to 350 MeV calculated with database of JENDL-HE 2007. We obtain a set of data about the angular distribution and energy spectra of produced neutrons on some heavy targets with energy ranges as stated above. From the results of neutron spectra, the paper also gives many comments to recommend a choice of materials for target and energies for accelerating proton beam . From the angle distribution of neutrons generated in (p, n) reactions on the different targets with the different energies of proton, the solutions to arrange the reflection bars in reactor proposed. A comparison is also made to improve the reliability for calculation of the paper.