Gamma-Ray Imaging Concepts
Oak Ridge National Laboratory
The ability of gamma-rays to penetrate matter makes them an excellent signature for the detection of nuclear materials—except that this very ability makes their detection difficult. This is particularly true if one wishes to make images, since general purpose focusing optics do not exist. Various indirect imaging techniques have been successfully applied to obtain gamma-ray images, including Compton and coded-aperture imaging. This paper will review the different approaches, and discuss their advantages and disadvantages as illustrated with results obtained from different instruments designed for use in nuclear security applications.