Fast transportation system evaluation at the Danish Mach 1 irradiation facility

The sensitivity of short-lived indicator isotopes in neutron activation analysis depends on the rapidity with which the sample is moved out of the irradiation position. The precision and accuracy of the analytical result, however, are determined by the random and systematic errors in the duration of the irradiation and decay prior to the measurement. Transportation systems differ considerably with respect to the influence of factors such as pressure, temperature, sample weight, and interaction between irradiation and decay times. The Mach 1 transportation system for the Danish Reactor DR 3 has been investigated experimentally, and a determination of its performance characteristics makes it possible to estimate the a priori precision of analytical methods based on indicators with half-lives down to 20-25 ms. (author)