Gamma-ray Emission Tomography: Modelling and evaluation of partial-defect testing capabilities

摘要: Assessment of gamma emission tomography (GET) for spent nuclear fuel verification is the task in IAEA MSP project JNT1955. In line with Safeguards RD (1) counting pins tomographic images without any a priori knowledge assembly under study, and (2) quantitative measurements pin-by-pin properties, e.g. burnup, detection anomalies and/or operator-declared data.Previous performed Sweden Finland have proven GET highly promising detecting removed or substituted (i.e. partial defects) BWR VVER-440 assemblies even down to individual pin level. The current adds previous experiences by pursuing assessment capabilities defect detection, across broad range potential applications, types, parameters. A modelling performance-evaluation framework has been developed provide performance predictions, incorporating burn-up cooling-time calculations, Monte Carlo radiation-transport detector-response modelling, instrument definitions (existing notional) reconstruction algorithms, which use recorded gamma-ray intensities produce cross-sectional source distribution conclusive data. also comprises image-processing algorithms metrics that recognize inherent trade-off between probability missing false-alarm rate. Here, analysis described preliminary results are presented.