Activity Standardization and Nuclear Decay Data of super(109)Cd

Activity standardization and nuclear decay data of super(109)Cd are presented. An ampoule containing the calibrated super(109)Cd solution is sent to the Bureau International des Poids et Mesures to include the activity result in database of the International Reference System (SIR). It is observed that the emission rate of conversion electrons is measured by means of pressurized proportional counters as well as by a liquid scintillation spectrometer. The combination of the results with the photon emission rate measured with the aid of gamma-ray spectrometers yields the activity concentration. It is found that the measurement results are also used to deduce emission probabilities with high accuracy.