Numerical stability problems in the k0-standardization method for the case of short irradiation and counting times

The k0-standardization method of neutron activation analysis (NAA) is very sensitive to the irradiation and counting time during measurement of the induced radionuclide by γ-spectrometry on the HP Ge detector. If the irradiation and counting time of the sample and co-irradiated standard is relatively short or the decay constant small, the application of the standard equation in the software for the specific count rate may become numerically unstable and the program aborts. Attention is focused on the direct influence of saturation and 'measurement' factors on the specific count rate for simple decay and for more complex types calculated directly by exponential functions, and by an alternative form using a truncated Taylor's series expression. (author)