GAMMA-RAY IMAGING WITH COMPTON CAMERAS

Compton cameras use the kinematics of Compton scattering to construct a source image without the use of collimators or masks. Compton telescopes were first built in the 1970s for astronomical observations. The first laboratory instrument was designed for medical imaging. Recently, three dimensional imaging has been demonstrated using an array of high resolution germanium detectors for characterization of mixed radioactive waste containers. Image resolution depends on the detector accuracy in both energy and position and on the image reconstruction algorithm. Advantages of Compton imaging include a wide field of view, background suppression, the ability to image high energy gamma rays (up to 10 MeV) and the ability to obtain three dimensional images from a fixed position on one side of the source without the need for tomography. The operation of Compton cameras will be reviewed along with recent results and future prospects.