On the contribution of prompt gamma neutron activation analysis to the element chracterization of environmental objects

Prompt gamma neutron activation technique has been established at Dalat nuclear research reactor providing a multielement analytical method complementary to the existing INAA techniques with delayed gamma rays measurements. The results of analysis of environmental standard reference materials show the capability of this technique in determining the concentrations of H, B, C, N, Cl, K in biological and B, Al, Si, K, Fe, Gd, Sm in non-biological samples. The instalation of a single crystal of silicon in the beam tube has considerably improved the quality of the thermal neutron beam and therefore, the contrast of the prompt gamma spectra. However, the rather low thermal neutron flux at the tangential horizontal channel did not allow to achieve the detection limits at sub-ppm concentration levels. The use of a more intensive filtered thermal neutron beam available at the piercing horizontal channel could considerably improve this situation. (author). 3 figs, 7 refs, 3 tabs