Measuring the radium-226 activity using a multidetector γ-ray coincidence spectrometer

• Published in: Journal of environmental radioactivity Vol. 100; no. 10; pp. 823 - 830
• Main Authors: Antovic, N., Svrkota, N.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-10-2009; Elsevier
• Subjects: Applied sciences; Atmospheric pollution; Dispersed sources and other; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Multidetector 4π-spectrometer; Pollution; Pollution sources. Measurement results; Pollution, environment geology; Radiation Monitoring - methods; Radium - analysis; Radium-226; Soil - analysis; Soil Pollutants, Radioactive - analysis; Spectrometry, Gamma - instrumentation; γ-coincidences; Europe; Montenegro; Radium-226; Multidetector 4π-spectrometer; γ-coincidences; Natural origin pollution; Radioactive pollution; Natural radioactivity; Radioisotope; Radium 226; Radioactivity measurement; Coincidence method; Geogenic factor; Air pollution; Measurement method; Gamma spectrometry
• ISSN: 0265-931X; 1879-1700
• DOI: 10.1016/j.jenvrad.2009.06.003

The method is based on coincidence counting of the 609
keV photons from two-, three- and four-step cascade transitions which follow β
−-decay of
214Bi, developed on the six-crystal spectrometer PRIPYAT-2M. As regards the determination of the activity of
226Ra and its decay products, the double coincidences mode of counting is the optimum one because of the highest spectrometer sensitivity. Minimum detectable radium activity concentration in that mode of counting in a soil sample is estimated to be 0.68
Bq
kg
−1 for live measuring time of 897.4
s, while it was 2.03
Bq
kg
−1 over 10 002.9
s in the case of the HPGe spectrometer. Using the double coincidences method, the
226Ra activity was determined in soil and sand samples from the Coastal region of Montenegro. The measurements were performed much faster than when an HPGe spectrometer is used, and the results showed relatively low level of the radium activity concentration.