Investigation of the Self-Interrogation Neutron Resonance Densitometry applied to spent fuel using Monte Carlo simulations

Neutron absorbers and detector types for spent fuel verification using the self-interrogation neutron resonance densitometry

“…To quantify the attenuation of the neutron flux around the 0.3 eV energy region the so-called SINRD signature, defined in [3] as the ratio between the energy-integrated values of the neutron flux in the fast region (FAST, i.e. 0.1-20 MeV) and in the region close to the resonance (RES, i.e.…”

“…This configuration ensures better condition for SINRD in comparison with the case of fuel stored under water, because the neutron moderation occurring within the fuel pins when the fuel assembly is stored under water washes out the reduction of the neutron flux around 0.3 eV used for the SINRD technique [3]. In addition, the dry conditions used as reference in this study can be representative of the encapsulation plant foreseen to be built in Sweden over the coming years [11].…”

“…As part of the international effort on the development of advanced NDA methods, the Belgian nuclear research center SCK Á CEN is carrying out the investigation of the Self-Interrogation Neutron Resonance Densitometry (SINRD, [3]). SINRD is a passive neutron technique that aims at directly quantifying the 239 Pu mass in a fuel assembly by measuring the attenuation of the neutron flux in the energy region close to 0.3 eV, because 239 Pu has a strong resonance in the total cross-section around that energy [4].…”

“…The approach proposed in [3] considered the fuel assembly in air surrounded by a thick slab of polyethylene to ensure neutron moderation, while the neutron detector is placed in the central guide tube of the assembly. This configuration ensures better condition for SINRD in comparison with the case of fuel stored under water, because the neutron moderation occurring within the fuel pins when the fuel assembly is stored under water washes out the reduction of the neutron flux around 0.3 eV used for the SINRD technique [3].…”

Non-destructive assay of nuclear materials using a self-indication method

“…Therefore, we proposed a new concept of "selfindication method" in the previous work [7,8]. A similar method called "Self-Interrogation Neutron Resonance a e-mail: hori@rri.kyoto-u.ac.jp Densitometry (SINRD)" was reported as a NRD technique to directly measure the fissile content [9][10][11]. In the selfindication method, an indicator consisting of the target nuclide with a high purity is placed at the neutron beam downstream from a sample.…”