| The SLOWPOKE reactor at École Polytechnique de Montréal is used to perform chemical analysis for samples using neutron activation analysis (NAA). This technique works correctly when the sample to analyze is a weak neutron absorber. However, when a sample contains a large amount of isotopes that are strong neutron absorbers, the analysis result will be wrong because the presence of this type of isotopes changes the flux distribution in the sample. This natural effect, known as spatial self-shielding, is difficult to model using codes like SERPENT (Monte Carlo code) and DRAGON (deterministic code) because of the small size of the samples.;The aim of this project is to propose simplifying models that can be used in simulation codes to evaluate in an accurate and efficient way the spatial neutron self-shielding effect. |
