X-ray Sources for Adaptive Radiography and Computed Tomography

X-ray multi-energy adaptive security radiography and computed tomography inspection techniques have superior performance compared to conventional dual-energy methods where two image slices are acquired by alternating energies. This new technique allows improving the quality of radiographic and CT images, expanding the range of areal densities of the interrogated objects over which effective discrimination of materials by atomic number is possible, eliminating artifacts in the image of boundaries of different densities, and reducing the time of inspection and the required dose. For this new inspection technology, RadiaBeam Technologies is developing several new types of x-ray sources that are based on linear electron accelerators. To provide an adaptive mode of operation of inspection systems, such accelerators use fast feedback from the detector array. Depending on the application, the range of the electron energy can vary from 180 keV up to 9 MeV. In this paper, we discuss the requirements for such linear accelerators, some details about their designs, and present the results of high-power and beam testing of the S- and X-band accelerators.