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Updated: May 23, 2026
08:43
Separation of Uranium and Thorium for 230Th-U Dating of Submarine Hydrothermal Sulfides
Published on: May 20, 2019
Measurement of the 230U half-life
S Pommé1, T Altzitzoglou, R Van Ammel
1European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium. stefaan.pomme@ec.europa.eu
Summary
The uranium-230 (230U) half-life was precisely measured using multiple nuclear detection techniques. The new value of 20.23 days refines previous estimates and suggests a potential correction for ingrowth of daughter products.
Area of Science:
- Nuclear Physics
- Radiochemistry
- Metrology
Background:
- Accurate half-life determination is crucial for nuclear science applications and understanding radioactive decay processes.
- Previous measurements of the uranium-230 (230U) half-life may be subject to uncertainties, potentially due to uncorrected ingrowth of daughter products.
Purpose of the Study:
- To precisely determine the half-life of uranium-230 (230U) using a variety of modern nuclear detection techniques.
- To compare the new measurement with existing literature values and investigate potential reasons for discrepancies.
Main Methods:
- Decay curve analysis of 230U sources over 100-200 days.
- Utilized multiple detection methods including alpha-particle counting, 4πα+β counting (CsI spectrometer, liquid scintillation, proportional counter), and gamma-ray spectrometry (HPGe detector).
- Employed nearly-2π alpha-particle counting with an ion-implanted silicon detector.
Main Results:
- Measurement results from various techniques showed good agreement.
- The determined mean half-life for 230U is 20.23 (2) days.
- This value is lower than the previously accepted literature value of 20.8 days, which lacked uncertainty.
Conclusions:
- The new, more precise half-life value for 230U has been established.
- The discrepancy with the older literature value may be attributed to a potential oversight in correcting for the ingrowth of long-lived lead-210 (210Pb) and its daughter products.
- This refined half-life improves the accuracy of nuclear data for 230U.
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