Thermal Neutron Flux Estimation in the Inner and Outer Irradiation Channels of NIRR-1 Leu Core

This research work focused on the determination of the effective cross-section and thermal neutron flux of the inner (B2) and outer (B4) irradiation channels of the Nigeria Research Reactor-1 (NIRR-1). The effective cross-section for the inner (B2) and outer (B4) irradiation channels was found to be 1.85×10-22cm2 and 1.28×10-22cm2respectively. This shows that B2 has a higher effective cross section than B4 which means that B2 will have more particle collision and produce more energy than B4. The thermal neutron flux for inner (B2) and outer (B4) irradiation channels were found to be and respectively. This shows that the outer (B4) channel is more thermalized than the inner (B2) irradiation channel because the more fission, the more the thermal neutron flux produce. This signifies that B4 will produce more heat and energy than B2; meanwhile, B2 absorbed and scatter more neutrons by the materials in the reactor than B4 because B2 has lower neutron flux than B4. The results can help provide information about the reactor's operation, especially in neutron activation analysis and fuel management decisions to enhance its performance, safety, and efficiency.