CALCULATION AND MEASUREMENT OF DEPTH-DOSE DISTRIBUTIONS IN BRICKS

The dose accumulated in bricks exposed to gamma radiation can be measu red as a function of depth using luminescence methods. The dependence of dose on depth has the potential of providing information on the ene rgy as well as on the angular distribution of the incident radiation, which could give indications pn the configuration of the radiation sou rces. A prerequisite for such an analysis is a comprehensive knowledge on the dependence of dose on depth for different source energies and for specific source configurations. Depth dose distributions in brick walls have been calculated by Monte Carlo simulations for a source dis tribution on a wall, for a source distribution on the ground and for a parallel photon beam, for source energies ranging from 140 keV to 160 0 keV. It is shown that depth dose distributions depend substantially on source configuration and energy. Depth dose distributions measured in ceramic material irradiated in the laboratory and in a brick from a contaminated area are compared with results of Monte Carlo calculatio ns.