Abstract: A method for automating and extending the density range for gamma ray attenuation correction algorithms for all classes of non-destructive assay systems including those without automated shutters or automated collimators. A system and software for implementing the method are also provided. The system features a dual-intensity transmission source and utilizes a three pass scanning protocol. The high-energy source in conjunction with a beam modulator produces a high and low energy beam. Automated software determines which beam data to use in tomographic reconstruction of an object being scanned.

Abstract: A device and method for measuring the relative amounts of 235U and 238U in the gaseous phase of UF6 using tunable diode laser spectroscopy (TDLS). The invention is a faster, more accurate method for making such measurement. The improved method involves using methane (CH4) or acetylene (C2H2) as a calibration gas, and using a Fabry-Perot interferometer to calibrate the laser frequency, to determine the relative amounts of 235U and 238U in UF6 gas within ±0.27% accuracy, for example 7.00%±0.27%. The sample time required for such measurement is about one second.