Prospects of Thulium-170 as a radiography source

Thulium -170 can be a useful source for radiography of very low thickness or low-density material. The radiological properties are complex due to the different soft gammas and x-rays emitted by this isotope. The radiation output and the attenuation through materials can vary to a large extent for Thulium-170 depending on the self-absorption and encapsulation of the source because of its low energy components. Calculations are done using a Monte Carlo code MCNP (ver.3.1) to find out the radiation output and attenuation through steel and lead for a given source configuration. Merits of the source as an industrial radiography tool and the problems encountered are highlighted in this paper. (author)