OPTIMIZATION OF THE PHOTONEUTRON FLUX EMITTED BY AN ELECTRON ACCELERATOR FOR NEUTRON INTERROGATION APPLICATIONS USING MCNPX AND TRIPOLI-4 MONTE CARLO CODES

Various applications require neutron interrogation to detect special nuclear material (SNM). Carrying out neutron interrogation measurements using the photoneutron flux emitted by an electron accelerator enables to reach average emission intensity on the order of two decades beyond the one produced by deuteriumtritium neutron generators traditionally used for such applications and enables to enhance neutron interrogation performance. In this paper, we characterize the photoneutron flux emitted by an electron accelerator in the energy range of 10 MeV to 20 MeV, and then, optimize the interrogative beam. In order to ensure accuracy and reliability of results, two Monte Carlo codes are used for this study: MCNPX and TRIPOLI-4.