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Published on: May 3, 2019
Activity determination and nuclear decay data of (113m)Cd
K Kossert1, O Nähle, P E Warwick
1Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany. karsten.kossert@ptb.de
Summary
Researchers precisely measured the radionuclide cadmium-113m ((113m)Cd) using advanced counting techniques. The study determined its gamma emission probability and a precise half-life of 13.97 years.
Area of Science:
- Nuclear physics
- Radiochemistry
Background:
- Accurate characterization of radionuclides is crucial for various applications, including nuclear medicine and environmental monitoring.
- Cadmium-113m ((113m)Cd) is a metastable nuclear isomer with potential applications requiring precise activity and decay data.
Purpose of the Study:
- To determine the activity of a (113m)Cd solution with high accuracy.
- To measure the gamma emission probability of the 263.7 keV line.
- To evaluate the half-life of (113m)Cd.
Main Methods:
- Irradiation of a cadmium component in a research reactor.
- Radiochemical separation to obtain a high-purity (113m)Cd solution.
- Activity determination using liquid scintillation counting with CIEMAT/NIST efficiency tracing and triple-to-double coincidence (TDCR) methods.
- Gamma-ray spectrometry for impurity analysis and quantification of the 263.7 keV gamma emission.
Main Results:
- A (113m)Cd solution of high radiochemical purity was prepared.
- The gamma emission probability for the 263.7 keV line was determined to be 0.01839(29)%.
- The half-life of (113m)Cd was measured to be 13.97(13) years over an 11-month observation period.
Conclusions:
- The study provides accurate metrological data for (113m)Cd, essential for its reliable use in various scientific and technical fields.
- The validated methods ensure the quality and precision of radionuclide characterization.
- The determined half-life and gamma emission probability contribute to the nuclear data library.
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