FLEX: a 2-9 MeV linac for x-ray detector and x-ray inspection development

The FLEX LINAC, developed and operated at RADIABEAM, is a workspace for the development and demonstration of MeV X-Ray inspection techniques. MeV energies from 2-9 MeV can be selected and can operate at up to 200Hz at various pulse widths and pulse timing. Currently, FLEX has been used in the evaluation of the recently developed GLO scintillators fabricated by LLNL, as well as commercially available scintillators. Horizons for additive manufacturing now include refractory metals: C103 Niobium, Molybdenum and Tungsten - engineered for high-temperature applications. Spatial resolution requirements for these objects/assemblies can be 0.1mm or smaller. Pairing the FLEX LINAC and monolithic GLO scintillators for MeV inspections (7-9 MeV) has demonstrated spatial resolution in the 0.1mm range for 2–3-inch chord lengths of refractory metals. We report here on scintillator evaluation results, and high-resolution MeV CT data acquired from R&D partnerships with NASA and NC State. We consider the data presented here to highlight potential inspection-gaps for the current array of CT scanner configurations – and points to the need for developments in MeV scintillators and detectors.