Simulation of radon detection efficiency with small pulse ionization chamber based on Geant4.

Area of Science:

• Nuclear Physics
• Environmental Science
• Radiation Detection

Background:

• Radon measurement is critical for assessing health risks from natural radiation.
• Pulsed ionization chambers are vital for real-time radon detection but face space and portability challenges.
• Optimizing detector design requires balancing detection efficiency with practical constraints.

Purpose of the Study:

• To characterize and optimize small cylindrical and flat plate pulsed ionization chambers for radon measurement.
• To analyze the impact of geometry, electrode size, and operating temperature on detection efficiency.
• To provide guidance for designing efficient and portable radon detection instruments.

Main Methods:

• Utilized Geant4 Monte Carlo simulation toolkit for detector modeling.
• Simulated small cylindrical and flat plate pulsed ionization chambers.
• Analyzed detection efficiency based on variations in chamber geometry, electrode dimensions, and operating temperature.

Main Results:

• A cylindrical chamber (8 cm length, 2 cm radius) achieved 58% ± 4% efficiency and good portability.
• A flat plate chamber (7 cm length, 3 cm width) achieved 54% ± 3% efficiency and good portability.
• Optimal electrode size for cylindrical chambers and temperature effects (30°C for flat plate, 20°C for cylindrical) were identified, with efficiencies up to 63% ± 4%.

Conclusions:

• Geometric dimensions, electrode size, and operating temperature significantly influence pulsed ionization chamber performance.
• Specific designs for cylindrical and flat plate chambers demonstrate high detection efficiency and portability.
• Findings offer valuable reference for developing advanced small pulsed ionization chamber detectors for radon monitoring.