iv Differentiation of Radionuclides on Surfaces Using Autoradiographic Methods

This thesis describes work which relates to attempting to obtain quantitative data of radionuclides on surfaces using autoradiography. The main work focuses on introducing shielding in the form of aluminium sheets which attenuate the radiation. In addition a second method was also investigated which was based on summing together the total deposited energy of each impact event registered by the plate separately and comparing it to a set intensity level. The summing method did however not give any useful results other than being able to discriminate between alpha and beta radiation. The collection of the emitted radiation is performed by a photosensitive plate (Fujifilm BAS-MS) and then turned into useful data by a Fujifilm FLA-7000 scanner. The radiation intensity is quantified in a unit called PSL, which is an arbitrary unit used to describe the absorbed dose of the plate. The measurement of this intensity was made using Fujifilm Image Gauge which gives the total deposited intensity of the sample area. The samples measured were prepared by applying a radionuclide in a