Test measurements of thoron concentration using two ionization chambers AlphaGUARD vs. radon monitor RAD7

• Autorzy: Kochowska E. , Kozak K. , Kozłowska B. , Mazur J. , Dorda J.
• Języki publikacji: EN

Abstrakty

EN

The experiment aiming at testing the possibility of using AlphaGUARD monitors based on an ionization chamber for thoron measurements is presented. A single AlphaGUARD monitor working in the flow mode was applied to measure thoron concentration in the radon-free atmosphere. The sensitivity (correction factors) of the monitor to thoron was estimated by comparison with a RAD7 portable detector (Durridge Company), based on spectrometric analysis, in the thoron, radon-free atmosphere in a calibration chamber. This depends on the applied flow rate and changes from 8% for the flow rate of 0.3 dm3/min to 36% for 1 dm3/min. It was also revealed that the sensitivity of the monitor to thoron in the diffusion mode is equal to ca. 5% and may be neglected. The method involving two Alpha-GUARD monitors working in two different modes (diffusion and flow) at the same time may be used to evaluate radon and thoron concentration in the natural environmental conditions where usually both isotopes appear together. In this method thoron concentration is estimated as the difference of results obtained from two AlphaGUARD monitors multiplied by the correction factor corresponding to the applied flow rate. The devices based on spectrometric analysis, e.g. RAD7 seem to be a better tool for thoron measurements in the environmental conditions.

Słowa kluczowe

EN

radon; thoron; thoron concentration; ionization chamber

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2009
• Tom: Vol. 54, No. 3
• Strony: 189--192
• Opis fizyczny: Bibliogr. 10 poz., rys.

Twórcy

autor

Kochowska E.

autor

Kozak K.

autor

Kozłowska B.

autor

Mazur J.

autor

Dorda J.

• Laboratory of Radiometric Expertise, The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, 152 Radzikowskiego Str., 31-342 Kraków, Poland, Tel.: [phone], Fax: [phone],

Bibliografia

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