Feasibility studies of doing NRTA measurements using an AmBe neutron source

In this work a new approach for Neutron Resonance Transmission Analysis (NRTA) experiments is explored which forgoes a pulsed source for neutron generation and instead uses an isotopic neutron source such as americium beryllium (AmBe) or 252Cf. This would make the experimental setup compact and mobile and would allow for on-site material identification having applications in the field of nuclear safeguards and security. In other NRTA experiments a pulsed neutron beam is required for providing a time reference to calculate the time-of-flight of neutrons. Instead, the setup proposed in this study uses an active moderator-detector for providing the reference time signal. A liquid scintillator detector acts as a moderator with hydrogenous material to reduce the energy of the neutrons emitted while also providing the start time of the time-of-flight. Energy of the transmitted epithermal neutrons is provided by the time-offlight measurement between the moderator-detector and a 6Li-doped GS20 disk. Experimental geometry and first set of experimental results obtained for a Ag target are presented in this report. These results provide a proof-of-concept, and will inform future experimental measurements.