Americium isotope analysis by Thermal Ionization Mass Spectrometry using the total evaporation method

Abstract In this paper, a simple analytical procedure was developed to measure americium isotope ratios and concentration with high accuracy. The method was tested during the participation in a round robin test organized by the Analytical Methods Committee of the French Atomic Energy Commission. The measurements were performed by Thermal Ionization Mass Spectrometry using the total evaporation method, which is a reference technique for determining actinide isotopic compositions. Expanded uncertainties were estimated at 0.1% and 0.8% for the 241 Am/ 243 Am isotope ratio and the Am concentration, respectively. Compared to the assigned value, biases below 0.0001% and 0.02% were calculated for the 241 Am/ 243 Am isotope ratio and the Am concentration, respectively.