Standardization of (18)F using the 4pi(beta+gamma) integral counting technique

Area of Science:

• Nuclear Physics
• Radiochemistry
• Metrology

Background:

• Accurate standardization of positron-emitting radionuclides like Fluorine-18 (18F) is crucial for nuclear medicine and research.
• Traditional methods for radionuclide standardization often rely on coincidence counting with efficiency extrapolation, which can introduce uncertainties.

Purpose of the Study:

• To adopt and validate the alpha 4pi(beta+gamma) integral counting technique for the standardization of 18F.
• To assess the efficiency and accuracy of this integral counting method compared to conventional techniques.

Main Methods:

• Utilized a 4pi(beta+gamma) integral counting setup with a beta detector (plastic scintillators sandwiching the source) inserted into a well-type NaI(Tl) scintillation detector.
• Employed EGS5 Monte Carlo simulations to verify the low inefficiency of the integral counter for the beta-plus decay branch.
• Compared results with a conventional 4pibeta-gamma coincidence counting method using efficiency extrapolation.

Main Results:

• The 4pi(beta+gamma) integral counting technique demonstrated high detection efficiency for both positron particles and annihilation quanta.
• EGS5 simulations confirmed a very small inefficiency for the beta-plus branch using the integral counter.
• Results obtained via the integral counting method were in agreement with those from the conventional efficiency extrapolation technique within experimental uncertainties.

Conclusions:

• The alpha 4pi(beta+gamma) integral counting technique is a reliable and accurate method for the standardization of 18F.
• This integral counting approach offers a viable alternative to conventional methods, potentially reducing uncertainties in radionuclide standardization.
• The study validates the integral counting technique for positron-emitting isotopes, contributing to advancements in radioactivity metrology.