Biological Dosimetry for Gadolinium Neutron Capture Reaction

Abstract

In gadolinium neutron capture reaction, photons and electrons of broad energy levels, from 20 or 30 KeV up to 7.9 MeV, are released. We have previously reported that electrons are the significant component of the over-all radiations involved in this reaction (Akine et al., 1992). Dose distributions for released photons have been reported previously (Brugger et al., 1989; Matsumoto, 1992), but dosimetry for electrons has yet to be elaborated (Masiakowski et al., 1992). This makes it impossible to estimate total absorbed doses in gadolinium neutron capture therapy. We have, therefore, carried out a biological dosimetry study using Chinese hamster cells as reported previously (Akine et al., 1990). Our intention was to derive an equation which enables us to estimate equivalent x-ray doses for any combination of gadolinium concentration and neutron fluence.