Development of a table-top NRTA system using a 252Cf neutron source
(2) Neutron time-of-flight demonstration using Cd, Hf & In thin samples

A compact table-top Neutron Resonance Transmission Analysis (NRTA) system has been developed to facilitate the sensitive assay of nuclear materials. This system features a neutron source composed of a 252Cf spontaneous neutron sealed source, which is moderated by a 3 cm thick high-density polyethylene and the neutron detector and lead block reflectors positioned on opposing sides. The design integrates collimators optimized through Monte Carlo simulations and a neutron detector capable of discriminating between gamma-ray and neutron. The neutron time-of-flight methodology was validated using the table-top NRTA system, specifically with thin samples of Indium, Hafnium, and Cadmium. The time-of-flight technique was employed to ascertain resonance energies, and the resultant experimental transmission was compared to theoretical expectations derived from Monte Carlo simulations. The experimental results along with the simulated data demonstrated accurate qualitative characterization of resonance energies below 5 eV. With a flight path length of 42 cm, this system provides a portable and cost-effective solution for nuclear material characterization, especially in the field of nuclear security, nonproliferation, and safeguards.