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Updated: May 30, 2026
14:19
A Basic Positron Emission Tomography System Constructed to Locate a Radioactive Source in a Bi-dimensional Space
Published on: February 1, 2016
Primary activity measurements with a 4πβ-4πγ coincidence counting system
Youcef Nedjadi1, Claude J Bailat, François O Bochud
1Institute of Radiation Physics, University Hospital and University of Lausanne, Lausanne, Switzerland. youcef.nedjadi@chuv.ch
Summary
A new 4πβ-4πγ coincidence counting system was established for standardizing radioactive concentrations. This system accurately measures low activity sources and short-lived radionuclides, validating its performance against primary methods.
Area of Science:
- Nuclear Physics
- Metrology
Background:
- Accurate standardization of radioactive concentrations is crucial for various scientific and industrial applications.
- Existing methods may have limitations in terms of sample preparation, efficiency, or suitability for short-lived radionuclides.
Purpose of the Study:
- To standardize the radioactive concentrations of holmium-166m ((166m)Ho), cesium-134 ((134)Cs), and barium-133 ((133)Ba).
- To validate a newly established 4πβ-4πγ coincidence counting system.
Main Methods:
- Utilized a 4πβ-4πγ coincidence counting system featuring a plastic scintillator beta detector and a NaI(Tl) monocrystal gamma detector.
- Employed optical filtering and electronic discrimination to vary beta detection efficiency.
- Standardized solutions of (166m)Ho, (134)Cs, and (133)Ba.
Main Results:
- The 4πβ-4πγ coincidence system demonstrated improved performance over previous methods.
- Achieved larger beta- and gamma-counting efficiencies, enabling efficient standardization of low activity sources.
- Successfully standardized the radioactive concentrations of (166m)Ho, (134)Cs, and (133)Ba.
Conclusions:
- The newly established 4πβ-4πγ coincidence counting system is validated and effective for standardizing radioactive concentrations.
- The system offers advantages in reduced sample preparation, increased efficiency, and suitability for short-lived radionuclides.
- Results agree with other primary measurement methods, confirming the system's accuracy.
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