Year
2024
Abstract
| Warhead confirmation could be a component of future arms control treaties, which may include measurements based on geometric attributes. Mature fast and thermal neutron imaging systems, such as the Neutron Coded Aperture (NCA) system jointly developed by Oak Ridge National Laboratory and Sandia National Laboratories, are capable of measuring geometric attributes based on neutron emissions, however the NCA is not designed to protect sensitive geometric information. Here we present the usage of pixel-derived statistical metrics that can inform geometrical attributes without revealing sensitive geometrical information. In other words, we explore the usage of statistical metrics using the fast and thermal neutron counts in individual pixels without reconstructing neutron images. We present two metrics using the NCA as a test case measurement system: when combined, they are sensitive to object extent and position in the imaging field of view. With the fast and thermal neutron detection sensitivity of the NCA, we show how these metrics could inform confirmation of an example geometry-based attribute: “an assembly containing a physically extended fast-neutron source, completely enclosed by a moderating material.” Simulated data show that these metrics perform quite well; the inclusion of the expected detector response characteristics of more modern pixelated detector systems is expected to largely preserve the sensitivity of these metrics to geometrical attributes. |