Monte Carlo Shielding Analysis for an Accelerator Epithermal Neutron Irradiation Facility (AENIF) in a Conventional X-Ray Irradiation Room

An Accelerator Epithermal Neutron Irradiation Facility (AENIF) was proposed for BNCT[1]. The proposed AENIF consists of a low-energy high-current proton accelerator, a high energy beam transport system, a target assembly, and a moderator assembly. The accelerator generates a 30 mA-2.5 MeV proton beam. The protons strike the 7Li target and create neutrons via the 7Li(p,n)7Be reaction. The source neutrons, having an average energy of about 400 keV, are too energetic for BNCT. Therefore a moderator assembly is used to degrade the energy of the neutrons to epithermal energies (1 eV- 1 keV). It is the purpose of this study to investigate the dose equivalent to radiation therapy personnel, if the moderator assembly is placed inside a conventional x-ray irradiation room.