Thoron detection with an active Radon exposure meter--first results

Area of Science:

• Environmental Science
• Nuclear Physics
• Radiation Detection

Background:

• Current Radon and Thoron discrimination techniques are often bulky and power-intensive.
• Existing monitoring devices are unsuitable for personal exposure assessment.
• The Helmholtz Center Munich (HMGU) previously developed a Radon exposure meter.

Purpose of the Study:

• To develop a new, compact, and low-power electronic prototype for continuous Radon/Thoron monitoring.
• To enable personal exposure monitoring through a portable device.
• To differentiate between Radon and Thoron isotopes and their decay products.

Main Methods:

• Utilizing a pin-diode detector system.
• Employing alpha-particle spectroscopy for decay identification.
• Implementing coincidence event registration for isotope discrimination.
• Developing a passive-sampling, low-power electronic design.

Main Results:

• Preliminary calibration in open geometry indicates a sensitivity of 1 count per hour for an 11 Bq m⁻³ Radon atmosphere.
• Preliminary calibration in open geometry indicates a sensitivity of 1 count per hour for a 15 Bq m⁻³ Thoron atmosphere.
• The prototype demonstrates potential for continuous concentration measurements.

Conclusions:

• The developed electronic prototype shows promise for accurate and portable Radon/Thoron monitoring.
• The device's small size and low power consumption make it suitable for personal exposure monitoring.
• Future work will focus on performance evaluation in mixed Radon/Thoron environments.