Nuclear-spectroscopy based, first-generation, computerized tomography scanners

A number of inexpensive, nuclear-spectroscopy-based, first-generation, computerized tomography (CT) scanners have been built to satisfy most Lawrence Livermore National Laboratory (LLNL) CT inspection requirements. The authors describe these CT scanners in detail and discuss their advantages and disadvantages when compared to the more common and more recent current-integration-based scanners. The major advantage of nuclear-spectroscopy-based scanners is that they can be used to determine all internal, spatially distributed, effective-atomic-number and density map within the object. It is also shown, how these scanners can be used to acquire meaningful chemical information for nondestructive characterization of materials and dimensional information for evaluating assembled components