Coupling gamma ray spectrometry and tomography in a Bayesian frame

To investigate the possibility to characterize radioactive wastes using available information and measurements in a coherent frame, Bayesian formalism is built couple gamma-ray spectrometry tomographic scans. The gamma ray performed with four High Purity Germanium (HPGe) detectors placed around waste scanning 2 cm thick slices of drum Gamma Scanning mode. tomography provides density matrix identifies heterogeneities. unknown chemical composition heterogeneities handled two parameters that represent mass fractions carbon hydrogen fictive {C; Sn; H} material would show attenuation behavior similar true material. approach tested by simulating measurement 239Pu rays produced PuO2 sphere slice which distinctive zones have been identified tomography, presence 137Cs background. With studied simulated examples, depending on position, use prior allows decreasing plutonium uncertainty up factor 3 compared case when not used. In addition, posterior distribution having significant number event related mass,