Conceptual design of a thermal neutron radiography facility in the cyclotron 30 LC using the MCNPX cod

Abstract

The MCNPX code and the ENDF/B-VII cross-section library have been used to optimize the geometrical dimensions of the thermal neutron radiography facility (TNRF) based on the cyclotron 30 LC using a Be target as a neutron source and the Protons Beam Channel (PBC) with energy 15.0 MeV and 20.0 MeV. Thermal, epithermal and fast neutron energy ranges have been selected as < 0.4 eV, 0.4 eV–10 keV and >10 keV, respectively. The calculated values of the thermal neutron flux at the main collimator exit (MCE) have been estimated to be 1.31´10⁵ n/cm².s and 1.05´10⁵ n/cm².s, 1.97´10⁵ n/cm².s and 1.66´10⁵ n/cm².s for the ratio L/D = 90 and L/D = 110, and the PBC with energy 15.0 MeV and 20.0 MeV, respectively. In addition, the cooling system of the Be target has been designed using solid works program. The simulated results showed that the maximum temperature of the Be target is lower than the melting temperature of the Be target. The use of neutronic and gamma filters has been eliminated in the design phase reducing the economic cost had anyone thought to build this beam.