Publication Date:
2018-03-16
Description:
The mass thickness and atomic number of materials shielding radioactive sources emitting multiple resolvable gamma-ray energies can be characterized by measuring the attenuation and Compton scatter of emitted gamma rays in recorded spectra against estimated values for a suite of materials and thicknesses. Compton imaging using a maximum-likelihood expectation maximization-based reconstruction can be used to separate angular spectra allowing simultaneous characterization of multiple shielded sources. Using the described algorithm on experimental 133 Ba data, we demonstrate estimation of mass thickness and atomic number for iron, tin, and lead shields with another bare source in the field of view with average standard error of 0.6 g/cm 2 and 1.5, respectively, while an aluminum shield is reconstructed with ambiguous atomic number but correct thickness.
Print ISSN:
0018-9499
Electronic ISSN:
1558-1578
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Physics
