Host: The Japan Society of Mechanical Engineers
Name : The 30th International Conference on Nuclear Engineering (ICONE30)
Date : May 21, 2023 - May 26, 2023
Combatting nuclear terrorism and non-proliferation of special nuclear materials (SNMs) is of paramount importance to nuclear security around the world and constitutes one of the top 10 grand challenges of the 21st Century. A principal method of monitoring for the illicit movement of SNMs is through interrogation of cargo for tell-tale neutron radiation signatures, especially while in motion. However, there remains a significant technological gap in high efficiency real-time detection, making the rapid, non-destructive interrogation of cargo an arduous and uncertain process. The current state-of-the-art technology employs He-3 detectors which are ~x1000 more sensitive to thermal neutrons as compared to fast neutrons which then requires bulky shielding for neutron down scattering. This is because SNM fission generated neutrons are in the fast energy range. Therefore, He-3 detectors utilize a moderating material to reduce the energy of incoming neutrons which unfortunately also leads to a secondary undesirable effect of acting as a neutron absorbing material in front of the detector. To engage in optimal SNM monitoring, it is necessary to employ sensors that are operable in real-time, gamma/beta blind, and highly sensitive to both thermal and fast neutrons without a requirement for large quantities of moderating material as employed by the 50+y old He-3 detector technology. The novel Economical Acoustically Tensioned Metastable Fluid Detector (E-ATMFD) developed at Purdue University promises to meet and exceed such primary criteria. New operational modes include driving the system at frequencies located in the audible range (10.5-11.2 kHz) and increased pressure exerted on the sensing fluid. This paper work details the design and performance of the advanced E-ATMFD(Ver.1) sensor system using borated sensing fluid which demonstrated absolute efficiencies x10-15 greater than a state-of-the-art moderated Ludlum-42-49B (He-3) detector of equivalent size, when compared side-by-side for detecting and tracking a shielded and unshielded moving Plutonium-Beryllium (SNM surrogate of similar intensity) neutron source.
