Scattering and attenuation correction in emission tomography in the nuclear industry.

A multi-energetic gamma-ray source has been used in conjunction with titanium and water-bath phantoms to simulate the scattering and attenuation effects encountered in nuclear industrial applications. The effect of scattered photons on the image reconstructions has been investigated by the subtraction of varying fractions of the scattered counts from the photopeak counts. A dual energy attenuation correction has also been applied to the data. In order to evaluate the effects of these corrections a "fidelity" factor has been calculated.