New approach for monitoring of nuclear material in nitric acid solution using N(n,)N reaction

Sekine, Megumi ; Tomikawa, Hirofumi

The IAEA has proposed in its long-term R&D plan, development of real-time measurement technology for monitoring and verifying nuclear material movement continuously. At a PULEX reprocessing facility, HNO solution with dissolved spent fuel, such as FPs and nuclear materials, flows in pipes and stores in tanks. In order to detect and deter nuclear material being stolen from the process, measuring the 10.8 MeV rays emitted by N(n,)N reaction activated by spontaneous neutrons might be useful for continuous monitoring of liquid flow. In general, since high dose rays emitted from FPs are dominant below 3 MeV, it is expected that the 10.8 MeV peak would not be affected by the FP peaks. As the first step, some kinds of detectors and measurement configuration were analyzed through MCNP based on 10.8 MeV rays activated by neutrons from a Cf source.