Investigating Uranium Isotopic Distributions in Environmental Samples Using AMS and MC-ICPMS
Major, minor, and trace uranium isotopes were measured at Lawrence Livermore National Laboratory in environmentally acquired samples using different instruments to span large variations in concentrations. Multi-collector inductively-coupled plasma mass spectrometry (MC-ICPMS) can be used to measure major and minor isotopes: {sup 238}U, {sup 235}U, {sup 234}U and {sup 236}U. Accelerator mass spectrometry (AMS) can be used to measure minor and trace isotopes: {sup 234}U, {sup 236}U, and {sup 233}U. The main limit of quantification for minor or trace uranium isotopes is the abundance sensitivity of the measurement technique; i.e., the ability to measure a minor or trace isotope of mass M in the presence of a major isotope at M{+-}1 mass units. The abundance sensitivity for {sup 236}U/{sup 235}U isotope ratio measurements using MC-ICPMS is around {approx}2x10{sup -6}. This compares with a {sup 236}U/{sup 235}U abundance sensitivity of {approx}1x10{sup -7} for the current AMS system, with the expectation of 2-3 orders of magnitude improvement in sensitivity with the addition of another high energy filter. Comparing {sup 236}U/{sup 234}U from MC-ICPMS and AMS produced agreement within {approx}10% for samples at {sup 236}U levels high enough to be measurable by both techniques.
- Research Organization:
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 908086
- Report Number(s):
- UCRL-JRNL-218199
- Journal Information:
- Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Journal Name: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms Vol. 259; ISSN 0168-583X; ISSN NIMBEU
- Country of Publication:
- United States
- Language:
- English
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