CR-39 alpha particle spectrometry for the separation of the radon decay product 214Po from the thoron decay product 212Po

In this work, it is presented an experimental assembly based on electric capture of radionuclides in order to discriminate the alpha activity of 214Po (radon decay product) from 212Po (thoron decay product) one. The alpha activity was registered with CR-39 analyzing etch pit diameters and optical density. This discrimination may allow for the estimation of the relative contribution of the alpha activity due to thoron decay products compared to the total activity due to radon decay products.