Accuracy and precision of (238)Pu determination at fg level by alpha spectrometry using (239)Pu and (240)Pu amount analyzed by ICP-MS.
The accuracy and precision of the determination of (238)Pu amount at the fg (mBq) level by a combination of alpha spectrometry and inductively coupled plasma mass spectrometry (ICP-MS) were studied using a standard reference material (CRM 137-Plutonium [corrected] Isotopic Standard, National Bureau of Standards, Washington, D.C., USA). The activity of (238)Pu was calculated from the amount of (239)Pu and (240)Pu obtained by isotope dilution method and ICP-MS combined with the intensity ratio of (238)Pu/(239,240)Pu obtained by alpha spectrometry without adding spike. The results show that approximately 130 fg of (238)Pu can be analyzed within an accuracy of 7% bias and with 5-12% of total uncertainty. The examined analytical procedure was applied to the quantitative analysis of (238)Pu in water samples representing Safeguards inspection samples. The combination of alpha spectrometry and ICP-MS is useful for quantitative and isotopic analysis in low-level Pu samples. Also the method leads to improving the accuracy of (238)Pu determination because efficiency calibration is not necessary for alpha spectrometry.
Mácsik
Zsuzsanna
Z
Institute of Nuclear Techniques, Budapest University of Technology and Economics, Muegyetem rkp. 9, H-1111 Budapest, Hungary.
Shinonaga
Taeko
T
D013058:Mass Spectrometry / Q000379:methods*; D011005:Plutonium / Q000737:chemistry*; D015203:Reproducibility of Results
D011005:Plutonium