New radiation hodoscope developments for arms control treaty verification

It is pointed out that new developments in hodoscope radiation detection technology offer a wide range of capabilities for arms control treaty verification (ACTV) applications. This concept uses an array of radiation detectors to image or detect objects inside opaque containments. Hodoscope systems can detect neutrons and/or gamma-rays. The systems can be based on transmission of radiation through the objects, can detect radiation stimulated in the objects, or can detect intrinsic object radiation. Laboratory measurements to demonstrate a range of potential applications have been performed. Gamma-ray transmission hodoscopes can be used to inspect canisters, rail cars, etc. to monitor objects such as rocket motors. The use of relatively weak isotopic radiation sources makes it unnecessary to employ expensive and high-intensity accelerators. The heavy metal of nuclear warheads is characterized by strong gamma-ray absorption, and these materials could be counted by low-resolution tomography. Absorbers located in line with objects will themselves be detected, and sources located in the object region will be subtracted out as background. Intrinsic gamma-ray radiation from warheads can also be detected in a passive-instrument mode.<>