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Published on: August 6, 2018
Primary activity standardization of (57)Co by sum-peak method.
A Iwahara1, R Poledna, C J da Silva
1Laboratório Nacional de Metrologia das Radiações Ionizantes (LNMRI)/Instituto de Radioproteção e Dosimetria (IRD)/Comissão Nacional de Energia Nuclear (CNEN), Rio de Janeiro, Brazil. iwahara@ird.gov.br
Summary
The sum-peak method standardized Cobalt-57 (57Co) solutions for international traceability. This method achieved a 0.37% standard uncertainty in activity concentration measurements.
Area of Science:
- Nuclear physics
- Metrology
- Radiochemistry
Background:
- Accurate activity measurements are crucial for international traceability.
- Standardization of radioactive sources ensures consistency in nuclear measurements.
- International comparisons facilitate the validation of measurement techniques.
Purpose of the Study:
- To standardize a Cobalt-57 (57Co) solution using the sum-peak method.
- To achieve international traceability for activity measurements.
- To compare the sum-peak method with other measurement techniques.
Main Methods:
- Application of the sum-peak method for activity determination.
- Utilizing a planar germanium detector for measurements.
- Derivation of an analytical expression for accidental summing correction.
- Accounting for the 112 keV germanium characteristic X-ray escape peak.
Main Results:
- The sum-peak method was successfully applied to standardize 57Co.
- A standard uncertainty of 0.37% was achieved for the activity concentration.
- The results were compared with those from other measurement methods.
Conclusions:
- The sum-peak method provides a reliable approach for activity standardization.
- The method contributes to international traceability in activity measurements.
- The achieved uncertainty is comparable to other established techniques.
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