Determination of Picogram Quantities of Americium and Curium by Thermal Ionization Mass Spectrometry (TIMS)

Abstract

Americium / Curium / Mass spectrometry / Thermal ionization / Isotopie dilution / Resin bead SummaryPicogram quantities of curium and americium have been measured in solutions of natural elements and fission products by thermal ionization mass spectrometry using the resin bead method combined with isotopie dilution.The fixation yields of americium on a resin bead vary from 6%, when the element is extracted from a few ml solution, to 2% for an aliquot 15 times larger. For curium the yields vary from 6%, when it is extracted from a few ml of solution, to 1 % for an aliquot 5 times larger.The ionization yields with CAMECA ΤΗΝ 206 spectrometers are 1 ion for 3000 to 5000 atoms for the resin bead method and 1 ion for 25000 to 30000 atoms in the case of direct loading on a triple filament.The reliability is determined by comparison of the mass spectrometric results with those obtained by alpha spectrometry. The relative standard deviation on Cm and Am ratios measurements is ±0.2%.

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

“…Another advantage of TIMS analyses is the possibility to perform concentration determination by isotope dilution (ID-MS) with low uncertainty, lower than 1 % [10][11][12]. TIMS is frequently used for actinides isotope composition determination [6,7,[13][14][15][16][17][18], in particular for uranium and plutonium [4,5,8,[19][20][21][22]. On the other hand, americium metrological isotope analysis are rare, due to the lack of Certified Reference Material (CRM) [5].…”