LOCATING AND IMAGING SOURCES OF GAMMA-RADIATION AND X-RADIATION DIRECTLY OR THROUGH THICK SHIELDS

This paper is a continuation of research published earlier. It describ es the characterization of sensors that generate images of extended ar ea sources, scatter patterns from irradiated targets, and radiation so urces through walls of concrete and lead. Images of the primary source s as well as the photon scatter-patterns from the targets or container walls were produced. The unique directional sensitivity of the sensor s made it possible to locate a Cs-137 point source that produced a rad iation intensity of 13.4 mu rad (Tissue)/h (about 10 photons/cm(2)-s) at the detector, immersed in a radiation field of 79.8 mu rad (Tissue) /h from another cesium source. Radiation sources of Cs-137, Co-60, and 300 kV X-ray photons were used in the scattering and wall penetration experiments and Th-232 foils in the extended area source measurements .