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Plastic scintillator beta ray scanner for in-situ discrimination of beta ray and gamma ray radioactivity in soil

  • Bae, Jun Woo (School of Mechanical, Aerospace and Nuclear Engineering, Ulsan National Institute of Science and Technology) ;
  • Kim, Hee Reyoung (School of Mechanical, Aerospace and Nuclear Engineering, Ulsan National Institute of Science and Technology)
  • Received : 2018.11.30
  • Accepted : 2019.11.12
  • Published : 2020.06.25

Abstract

A beta ray scanner was proposed for in-situ discrimination of beta and gamma ray radioactivity. This scanner is based on the principle that gamma and beta rays experience different changes in detection efficiency in scintillators with different geometries, especially with regard to the scintillator thickness. The ratios of the counting rates of gamma rays (Rgamma), beta rays (Rbeta), and sample measurements (Rtotal) in a thick scintillator to those in a thin one are reported. The parameter Xthick, which represents the counting rate contributed by beta rays to the total counting rate in the thick scintillator, was derived as a function of those ratios. The values of Rgamma and Rbeta for 60Co and 90Sr sources were estimated as 3.2 ± 0.057 and 0.99 ± 0.0049, respectively. The estimated beta ray contributions had relative standard deviations of 2.05-4.96%. The estimated range of the beta rays emitted from 90Sr was 19 mm as per the Monte Carlo N-Particle simulation, and this value was experimentally verified. Homogeneous and surface contaminations of 60Co and 90Sr-90Y were simulated for application of the proposed method. The counting rate contributed by the beta rays was derived and found to be proportional to the concentration of 90Sr-90Y contamination.

Keywords

References

  1. D.K. Cho, H.J. Choi, R. Ahmed, G. Heo, Radiological characteristics of decommissioning waste from a CANDU reactor, Nucl. Eng. Technol. 43 (2011) 583-592. https://doi.org/10.5516/NET.2011.43.6.583
  2. M.F. L'Annunziata, Handbook of Radioactivity Analysis, Vol third ed, Academic Press, Amsterdam, 2012, pp. 576-609.
  3. C. Miro, A. Baeza, M.J. Madruga, R. Perianez, Caesium-137 and strontium-90 temporal series in the Tagus river: experimental results and a modelling study, J. Environ. Radioact. 113 (2012) 21-31. https://doi.org/10.1016/j.jenvrad.2012.04.012
  4. H. Miyoshi, T. Ikeda, Preparation of paper scintillator for detecting H-3 contaminant, Radiat. Prot. Dosim. 156 (2013) 277-282. https://doi.org/10.1093/rpd/nct079
  5. C.H. Shao, C.C. Lu, T.R. Chen, J.H. Weng, P.F. Kao, S.L. Dong, M.J. Chou, Monitoring of radiation dose rates around a clinical nuclear medicine site, Radiat. Phys. Chem. 104 (2014) 124-128. https://doi.org/10.1016/j.radphyschem.2013.12.034
  6. H. Cember, Introduction to health physics, McGraw-Hill, Health Professions Division, New York; London, 1996, pp. 432-434.
  7. S. Usuda, H. Abe, A. Mihara, Simultaneous counting of alpha-rays, beta rays and gamma rays with phoswich detectors, J. Alloy. Comp. 213 (1994) 437-439.
  8. S. Yamamoto, J. Hatazawa, Development of an alpha/beta/gamma detector for radiation monitoring, Rev. Sci. Instrum. 82 (2011) 113503. https://doi.org/10.1063/1.3658821
  9. K. Yasuda, S. Usuda, H. Gunji, Simultaneous alpha, beta/gamma, and neutron counting with phoswich detectors by using a dual-parameter technique, IEEE Trans. Nucl. Sci. 48 (2001) 1162-1164. https://doi.org/10.1109/23.958743
  10. E. Furuta, T. Kawano, A plastic scintillation counter prototype, Appl. Radiat. Isot. 104 (2015) 175-180. https://doi.org/10.1016/j.apradiso.2015.06.035
  11. T. Maekawa, S. Makino, A. Sumita, T. Goto, Long scintillation detector using composite light guide for beta ray survey measurement, J. Nucl. Sci. Technol. 48 (2011) 50-59. https://doi.org/10.1080/18811248.2011.9711678
  12. T. Maekawa, A. Sumita, S. Makino, Thin beta ray detectors using plastic scintillator combined with wavelength-shifting fibers for surface contamination monitoring, J. Nucl. Sci. Technol. 35 (1998) 886-894. https://doi.org/10.1080/18811248.1998.9733961
  13. International Commission on Radiation Units and Measurements, Stopping powers for electrons and positrons, in: International Commission on Radiation Units and Measurements, 1984.
  14. G.F. Knoll, Radiation Detection and Measurement, Wiley, Hoboken, N.J, 2010, pp. 85-92.
  15. T.J. Yasunari, A. Stohl, R.S. Hayano, J.F. Burkhart, S. Eckhardt, T. Yasunari, Cesium-137 deposition and contamination of Japanese soils due to the Fukushima nuclear accident, Proc. Nat.Acad. Sci. 108 (49) (2011) 19530-19534. https://doi.org/10.1073/pnas.1112058108
  16. J.C. Callaway, R.D. DeLaune, W.H. Patrick Jr., Chernobyl 137Cs used to determine sediment accretion rates at selected northern European coastal wetlands, Limnol. Oceanogr. 41 (3) (1996) 444-450. https://doi.org/10.4319/lo.1996.41.3.0444
  17. International atomic energy agency, Application of the Concepts of Exclusion, Exemption and Clearance, IAEA Safety Standards Series No. RS-G-1.7, IAEA, Vienna, 2004, pp. 12-15.
  18. W.G. Cross, J. Bohm, M. Charles, E. Piesch, S.M. Seltzer, Report 56: dosimetry of external beta rays for radiation protection, Rep. Int. Comm. Radiat. Units Meas. os29 (1) (1997) 107-109, 5 January.
  19. U.A. Tarim, O. Gurler, E.N. Ozmutlu, S. Yalcin, Monte Carlo calculations for gamma ray mass attenuation coefficients of some soil samples, Ann. Nucl. Energy 58 (2013) 198-201. https://doi.org/10.1016/j.anucene.2013.03.021
  20. L. Wielopolski, Z. Song, I. Orion, A.L. Hanson, G. Hendrey, Basic considerations for Monte Carlo calculations in soil, Appl. Radiat. Isot. 62 (2005) 97-107. https://doi.org/10.1016/j.apradiso.2004.06.003
  21. B.L. Rosenberg, et al., Radionuclide pollution inside the Fukushima Daiichi exclusion zone, part 1: depth profiles of radiocesium and strontium-90 in soil, Appl. Geochem. 85 (2017) 201-208. https://doi.org/10.1016/j.apgeochem.2017.06.003
  22. L.M. Kagan, V.B. Kadatsky, Depth migration of Chernobyl originated 137Cs and 90Sr in soils of Belarus, J. Environ. Radioact. 33 (1) (1996) 27-39. https://doi.org/10.1016/0265-931X(95)00068-L
  23. K.K. Hamamatsu Photonics, Photomultiplier tubes: photomultiplier tube and related products, 2016, pp. 44-45.
  24. E.W. Abelquist, W.S. Brown, G.E. Powers, A.M. Huffert, Minimum detectable concentrations with typical radiation survey instruments for various contaminants and field conditions (NUREG-1507), in: U.S. Nuclear Regulatory Commission, Washington D. C, 1998, pp. 4-9.

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