Standardization of 241Am solution

The standardization of 241Am solution has been undertaken using a 4πβ-γ coincidence system. The 4π proportional counter used for alpha detection has a 0.1 mm thick Al window in the outside wall in order to minimize γ-ray attenuation. The extrapolation technique was applied to determine the activity of the solution. The variation of alpha efficiency has been made using external absorbers and by the electronic discrimination. The results from the two methods were compared and are in agreement within the experimental uncertainty.