A solid-state Compton camera for three-dimensional imaging

A Compton camera was constructed using four individual high-purity germanium (HPGe) coaxial detectors in the front plane and four elements of a 15 element HPGe coaxial array in the back plane. 60Co, 133Ba, and 137Cs sources were used in configurations that included single sources in positions covering the intended field-of-view and multiple sources of both identical isotopes and different isotopes. Experiments were also conducted with sources in waste-container sized attenuating media. This proof-of-concept experiment was designed to demonstrate non-tomographic three-dimensional imaging for the characterization of mixed waste containers. The present analysis demonstrates three-dimensional imaging of multiple sources at multiple energies and the imaging of sources within a waste-container sized attenuating medium.