Plutonium hot particle separation techniques using real-time digital image systems

Two real-time digital imaging systems, able to replace conventional autoradiography for radioactive hot particle separation and identification, are presented in this paper. The hot plutonium particles used for the study originate from the Thule nuclear weapon accident, Both of the real-time imaging techniques are initiated with sample splitting and measurements with a HPGe detector. in order to detect the gamma-emitting Pu-241 daughter Am-241, which is an indicator of plutonium hot particle in the sample. The time required for the whole process of separation and identification of one single particle from a bulk sediment sample (150 g dry weight) is of the order of 1-2 days, and is highly dependent on its activity. The real-time digital imaging systems presented in this paper are preferable, compared to conventional autoradiography and the CR-39 technique, when separation and identification of hot particles are needed as they are much faster and in addition give a real-time image of the particle. (C) 2002 Elsevier Science B.V. All rights reserved.