A neutron generator driver source for the subcritical assembly at Ontario Tech University

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Ontario Tech was recently gifted two of the three main parts of a subcritical assembly by another university in Canada. The single most important acquisition in the history of the Department of Energy and Nuclear Engineering, whilst the institution now has the nuclear fuel and accompanying graphite moderator for this intrinsically safe, special type of zero power reactor, it lacks a suitable external fast neutron source to drive it. Whilst the university has several small radioisotope neutron sources, as the neutron flux in a subcritical assembly is proportional to the strength of its driver neutron source, the resulting flux from these is too low to be useful for most experiments and hence a stronger neutron source is essential. Whilst stronger radioisotope neutron sources can be procured, they are expensive and given they are based on radioactive decay, their activity presents a significant radiation hazard that cannot be switched off. A suitable neutron source alternative known as a neutron generator, a type of electrostatic accelerator that only emits neutrons when powered on, has been identified and, if funded, will be the final puzzle piece needed to bring the subcritical assembly into mainstream use as a research facility supporting research across the university, as well as the specific needs of the applicant. The research outputs possible through use of a neutron generator in the subcritical pile are immeasurable. To satisfy the CNSC licensing timeframe, it is essential that funding for a neutron generator be approved before Summer 2023 else a five-year delay could result. Installed beneath the assembly for shielding purposes, the neutron generator is essential to realizing the full potential of what will be a unique in Canada nuclear energy research facility. It will support both fundamental and small modular reactor research and development and, being predominantly made of graphite, will help address current shortfalls in nuclear data. Given the intrinsically safe nature of subcritical assemblies, Ontario Tech intends to pioneer a multi-level student training scheme wherein both undergraduate and graduate students will be able to apply for subcritical operator and radiation protection roles. It is anticipated that up to 20 undergraduate and 10 graduate students will be accommodated on this scheme per annum. In all cases, students will undergo a structured training package involving completion of a suite of CNSC-approved micro credentials and hands on training, including training on the safe use of the neutron generator. This training program will exist in parallel to, and support, the research outputs for which the neutron generator is necessary. When not being used for research, the facility will be used for teaching and outreach activities.