Absolute 108Agm characterization based on gamma-gamma coincident detection by two NaI(Tl) detectors

Area of Science:

• Nuclear Physics
• Radiochemistry
• Radiation Detection and Measurement

Background:

• Accurate radioactive source activity determination is crucial for various applications.
• Existing methods for analyzing coincident gamma-rays have limitations for complex decay schemes.
• Previous work adapted Eldridge-Crowther formulas for two coincident gamma-rays.

Purpose of the Study:

• To develop and validate a method for measuring the activity of a radioactive source based on three coincident gamma-rays.
• To extend the analysis of coincident gamma-rays to more complex decay schemes, specifically for Silver-108m (108Agm).
• To determine detector efficiencies for multiple gamma-ray photopeaks using coincidence and anticoincidence measurements.

Main Methods:

• Utilized two Sodium Iodide (Thallium-activated) [NaI(Tl)] scintillation detectors for detecting coincident gamma-rays.
• Applied a modified Eldridge-Crowther formula approach to analyze three coincident gamma-rays from 108Agm decay.
• Performed measurements in both coincidence and anticoincidence modes to gather extensive experimental data.

Main Results:

• Successfully measured the source activity of 108Agm using the developed two-dimensional analysis.
• Determined the detector efficiencies for all three relevant gamma-ray photopeaks.
• The results obtained were compared with activity measurements performed using High-Purity Germanium (HPGe) detectors.

Conclusions:

• The presented method provides a viable approach for direct source activity measurement using three coincident gamma-rays.
• The adaptation of Eldridge-Crowther formulas is effective for more complex decay scenarios.
• The findings demonstrate the utility of NaI(Tl) detectors in conjunction with advanced analysis techniques for nuclear metrology.