Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1080/10256016.2023.2244651
Title (Primary) 226Ra measurement via gamma-ray spectrometry of 222Rn progeny – quantification of radon losses from sample capsules
Author Schubert, M.; Paschke, A.; Westmeier, W.
Source Titel Isotopes in Environmental and Health Studies
Year 2023
Department OEC; CATHYD
Volume 59
Issue 4-6
Page From 529
Page To 538
Language englisch
Topic T5 Future Landscapes
T9 Healthy Planet
Keywords Environmental tracer, gamma-ray spectrometry; isotope measurements methods and equipment; natural radioactivity; quantifying radon loss; radium-226; radon-222
Abstract Radium-226 detection in sediment samples is generally executed by means of gamma-ray spectrometry. Data evaluation relies (besides the 186.2 keV 226Ra gamma peak) on the combined analysis of major gamma peaks that are produced by the short-lived radon (222Rn) daughters 214Pb and 214Bi. Precondition for this detection approach is equilibrium decay of all members of the decay chain between 226Ra and 214Bi. In closed systems, this equilibrium is reached after about five half-lives of 222Rn (19 days). However, a closed system can only be guaranteed if the capsule which contains the sample prevents diffusive escape of radon. Such radon-tightness cannot be guaranteed for a wide range of plastic materials. Due to its polymer structure, plastic material generally tends to allow radon diffusion and hence radon loss from the sample resulting in a disturbance of the required decay equilibrium. The paper introduces an approach that allows quantifying radon loss from sample capsules by direct radon measurements using mobile radon detection equipment. The experimental findings are supported by theoretical considerations. An examined alternative approach based on the offset of the 186.2 keV data point from an efficiency function that is calculated exclusively from short-lived radon progeny peaks in the gamma-ray spectrum did not prove to be applicable due to a lack of supporting peaks in the low-energy section of the spectrum.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=27755
Schubert, M., Paschke, A., Westmeier, W. (2023):
226Ra measurement via gamma-ray spectrometry of 222Rn progeny – quantification of radon losses from sample capsules
Isot. Environ. Health Stud. 59 (4-6), 529 - 538 10.1080/10256016.2023.2244651