The US government conducts searches in urban areas for radiological/nuclear devices before special events, such as inaugurations. Optimizing the search patterns requires a 3D simulation capability validated by benchmark-quality measurements.
Modern radiation transport tools with automated variance reduction are being used to model both background and threat sources. Next-generation tools are being modified to handle CAD geometries, detailed detector responses, and motion.
Accurately modeling complex scenes will allow scientists to determine what type of sources can be seen from what locations, allowing for a better optimization of the search area. Resources can be deployed in a more cost-effective manner.