Abstract
The combined negative bias in gamma-spectrometry due to pile-up and (residual) dead time losses in case of short-lived radionuclides can be corrected for by way of dead time readings. The combined loss-factor depends on the ratio of the time-constants in amplifier and ADC, and on the average decay-constant over the total spectrum during measurement. Both parameters can be determined once and for all for a given routine application. The procedure is applicable up to total dead time fractions of at least 0.3 and thus covers routine instrumental neutron activation analysis (INAA) practice with short-lived radionuclides.