Abstract
The nucleon-meson transport code NMTC/JAERI97 is revised in the treatment of the angular distribution of the neutron elastic scattering for the energy region from 20 to 100 MeV. The approximation of the angular distribution with the first order Bessel function is changed to the random sampling based on the database evaluated by the optical model potential parameters (OMPs). For 43- and 68-MeV quasi-monoenergetic neutrons through iron, concrete and polyethylene shields, neutron transmission experiments are analyzed with the updated NMTC/JAERI97 code. It is shown that the updated NMTC/JAERI97 calculations agree well with the measured transmission neutron energy spectra and give significantly improved C/E values for the attenuation length in comparison with the results of the original version. It is also notable that the updated calculation represents quite well the measured neutron spectra at the positions of 20 and 40 cm off beam axis of the shields. Moreover, it is found that the cross sections evaluated by an OMP gives a better result than those by the systematics for the transmission calculation of neutrons with energies below 40 MeV.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.