Measurement of radium concentration in water with Mn-coated beads at the Sudbury Neutrino Observatory
العنوان: | Measurement of radium concentration in water with Mn-coated beads at the Sudbury Neutrino Observatory |
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المؤلفون: | T.C. Andersen, I. Blevis, J. Boger, E. Bonvin, M. Chen, B.T. Cleveland, X. Dai, F. Dalnoki-Veress, G. Doucas, J. Farine, H. Fergani, A.P. Ferraris, M.M. Fowler, R.L. Hahn, E.D. Hallman, C.K. Hargrove, P. Jagam, N.A. Jelley, A.B. Knox, H.W. Lee, I. Levine, S. Majerus, K. McFarlane, C. Mifflin, G.G. Miller, A.J. Noble, P. Palmer, J.K. Rowley, M. Shatkay, J.J. Simpson, D. Sinclair, J.-X. Wang, J.B. Wilhelmy, M. Yeh |
سنة النشر: | 2016 |
مصطلحات موضوعية: | Detection limit, Physics, Heavy water, Nuclear and High Energy Physics, Sudbury Neutrino Observatory, 010308 nuclear & particles physics, Solar neutrino, Counting efficiency, Analytical chemistry, FOS: Physical sciences, chemistry.chemical_element, 01 natural sciences, Ion, Radium, chemistry.chemical_compound, Adsorption, chemistry, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Instrumentation |
الوصف: | We describe a method to measure the concentration of 224Ra and 226Ra in the heavy water target used to detect solar neutrinos at the Sudbury Neutrino Observatory and in the surrounding light water shielding. A water volume of (50-400) m^3 from the detector is passed through columns which contain beads coated with a compound of manganese oxide onto which the Ra dissolved in the water is adsorbed. The columns are removed, dried, and mounted below an electrostatic chamber into which the Rn from the decay of trapped Ra is continuously flowed by a stream of nitrogen gas. The subsequent decay of Rn gives charged Po ions which are swept by the electric field onto a solid-state alpha counter. The content of Ra in the water is inferred from the measured decay rates of 212Po, 214Po, 216Po, and 218Po. The Ra extraction efficiency is >95%, the counting efficiency is 24% for 214Po and 6% for 216Po, and the method can detect a few atoms of 224Ra per m^3 and a few tens of thousands of atoms of 226Ra per m^3. Converted to equivalent equilibrium values of the topmost elements of the natural radioactive chains, the detection limit in a single assay is a few times 10^(-16) g Th or U/cm^3. The results of some typical assays are presented and the contributions to the systematic error are discussed. 25 pages, 8 figures. V2 shortened to 17 pages, 5 figures |
اللغة: | English |
URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c6a164e2e594e7efc5140a8cbeb8bff9 https://doi.org/10.1016/s0168-9002(03)00616-8 |
حقوق: | OPEN |
رقم الأكسشن: | edsair.doi.dedup.....c6a164e2e594e7efc5140a8cbeb8bff9 |
قاعدة البيانات: | OpenAIRE |
الوصف غير متاح. |