William L. Adams

Relocatable cargo x-ray inspection systems utilizing compact linacs

Magnetron-powered, X-band linacs with 3–4 MeV capability are compact enough to be readily utilized in relocatable high energy cargo inspection systems. Just such a system is currently under development at AS&E™ using the commercially available ISOSearch™ cargo inspection system as the base platform. The architecture permits the retention of backscatter imaging, which has proven to be an extremely valuable complement to the more usual transmission images. The linac and its associated segmented detector will provide an additional view with superior penetration and spatial resolution. The complete system, which is housed in two standard 40′ ISO containers, is briefly described with emphasis on the installation and operating characteristics of the portable linac. The average rf power delivered by the magnetron to the accelerator section can be varied up to the maximum of about 1 kW. The projected system performance, including radiation dose to the environment, will be discussed and compared with other high en...

Mobile large-vehicle inspection system design issues

X-ray systems capable of scanning semitrailers using conventional fanbeam technology are restricted to transmission-based imaging techniques that suffer from superposition of clutter. MobileSearchTM I is a truck-mounted 450 KeV pencil beam system incorporating x-ray backscatter imaging to produce near photo-like images, which was reported on in a paper by Swift in 1996. Since that time MobileSearchTM II added a transmission detector providing both backscatter and transmission in a single pass. The transmission detector design is the result of extensive x-ray and optical simulations. The radiation safety was studied extensively using the GEANT2 simulation system. The simulations were extended from 450 KeV to 5 MeV, to determine the safety implications of increasing the x-ray energy. Operationally, a 14 foot high, 8 foot 6 inch wide vehicle can be parked on a level area and the MobileSearchTM II system driven alongside to examine the contents. Deployment and setup are facilitated by having a self-contained system, which can be driven over the road and cen be operational in less than an hour. MobileSearchTM II is also capable of continuous mode scanning. In this mode, a line of vehicles can be scanned without having to stop and reposition or queue vehicles. The system is designed to fit in a C17 for easy air transport to a distant location.