Laboratory unit for scanning extended gamma-radiation sources

A laboratory unit was developed for determining the uniformity of photon ra diation distribution along extended sources. The unit allows measurements o f sources 10-1000 mm long, 0.5-20 mm in diameter, with a specific activity of 0.01-10 mCi cm(-1) in the discrete or continuous drawing mode. Discrete drawing is performed with a 1 or 5 mm step, and continuous drawing, at a ra te of 0.005-0.43 mm s(-1). The collimator slit width and length are 1-5 and 5-50 mm, respectively. Depending on the specific activity of the source an d the spectrum of the emitted photon radiation, an NaI(Tl), Si(Li), or cadm ium telluride detector is used. The data on radiation distribution along th e extended source is computer-processed using a specially developed program . A measurement mode and an original algorithm of processing the scanning h istogram are suggested to obtain more accurate data on the length of the ac tive part of the source and on the uniformity of photon radiation distribut ion along the source.