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Updated: Aug 9, 2026
08:53
Automated 90Sr Separation and Preconcentration in a Lab-on-Valve System at Ppq Level
Published on: June 6, 2018
Half-life evaluations for 3H, 90Sr, and 90Y
1National Physical Laboratory, Teddington, Middlesex TW11 0LW, UK. desmondmacm@yahoo.co.uk
Summary
This study applies data evaluation methods to tritium (3H) half-life data, recommending 4497(4) days. It also analyzes strontium-90 (90Sr) data trends and evaluates yttrium-90 (90Y) half-life, recommending 64.063(16) hours.
Area of Science:
- Nuclear Physics
- Radiochemistry
- Metrology
Background:
- Discrepant half-life data for radionuclides pose challenges in accurate scientific assessment.
- Previous work established methods for evaluating discrepant data using strontium-90 (90Sr) and cesium-137 (137Cs).
- Tritium (3H) half-life data underwent a comprehensive review, highlighting the need for applying advanced evaluation techniques.
Purpose of the Study:
- To apply established data evaluation techniques to tritium (3H) half-life data.
- To further analyze and address issues in the discrepant half-life data of strontium-90 (90Sr).
- To conduct a new evaluation of yttrium-90 (90Y) half-life data following recent measurements.
Main Methods:
- Application of data evaluation procedures developed by MacMahon et al. to tritium (3H) data from Lucas and Unterweger.
- Further analysis of discrepant strontium-90 (90Sr) half-life measurements, focusing on observed trends.
- Compilation and critical evaluation of all available published yttrium-90 (90Y) half-life data, incorporating new measurements.
Main Results:
- A recommended half-life of 4497(4) days for tritium (3H) was determined.
- Analysis of strontium-90 (90Sr) data revealed a persistent upward trend in measurements over time.
- A recommended half-life of 64.063(16) hours for yttrium-90 (90Y) was established based on consistent data.
Conclusions:
- The applied evaluation methods provide a robust framework for reconciling discrepant radionuclide half-life data.
- The upward trend in 90Sr data warrants continued investigation and potential revision of measurement protocols.
- The recommended half-lives for 3H and 90Y represent a significant update based on rigorous data analysis.
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