2016 CAP Congress / Congrès de l'ACP 2016

The Measurement of Actinides by Accelerator Mass Spectrometry

15 Jun 2016, 08:45

15m

Colonel By D103 (University of Ottawa)

Oral (Non-Student) / orale (non-étudiant) Instrumentation and Measurement Physics / Physique des instruments et mesures (DIMP-DPIM) W1-6 Instrumentation for the Detection of Low-Level Radioactivity (DIMP) / Appareillage de détection de radioactivité de faible intensité (DPIM)

Speaker

Jack Cornett (University of Ottawa)

Description

We developed a simple method to separate Pu and Am isotopes from the sample matrix using a single extraction chromatography column and to measure the concentrations of the isotopes by isotope dilution accelerator mass spectrometry (AMS). Pu and Am in the extraction chromatography column eluent were coprecipitated with NdF3 or Fe(OH)3 and the precipitates were analyzed by AMS at the University of Ottawa, A.E. Lalonde AMS Laboratory. The advantages of each precipitation method were assessed by studying the sensitivity, detection limits, and precision of the Am and Pu isotope measurements. The strongest AMS beams of Pu and Am were produced when there was a large excess of fluoride donor atoms in the target and the NdF3 precipitates were diluted with PbF2. The measured concentrations of Pu-239,240 and Am-241 agreed with the concentrations in standards of known activity and with IAEA certified reference materials. This work demonstrated that both oxide and fluoride targets produce reliable beams of actinide anions and that the measurement of actinides using fluorides agrees with measurements made using oxide precipitates and with the values in certified reference materials.