In this work, we addressed the inhomogeneity problem in gamma spectrometry caused by hot particles, which are dispersed into environment from large nuclear reactor accidents such as at Chernobyl and Fukushima. Using Monte Carlo simulation, we have determined the response of a gamma spectrometer to individual and grouped hot particles randomly distributed in a soil matrix of 1-L and 0.6-L sample containers. By exploring the fact that the peak-to-total ratio of efficiencies in gamma spectrometry is an empirical parameter, we derived and verified a power-law relationship between the peak efficiency and peak-to-total ratio. This enabled creation of a novel calibration model which was demonstrated to reduce the bias range and bias standard deviation, caused by measuring hot particles, by several times, as compared with the homogeneous calibration. The new model is independent of the number, location, and distribution of hot particles in the samples. In this work, we demonstrated successful performance of the model for a single-peak 137Cs radionuclide. An extension to multi-peak radionuclide was also derived.
References
[1]
Biagini, R., Dersch, R., de Felice, P., Jerome, S.M., Perkin, E.M.E., Pona, C., de Sanoit, J. and Woods, M.J. (1995) Homogeneity Testing of Spiked Reference Materials. Science of the Total Environment, 173-174, 267-274. https://doi.org/10.1016/0048-9697(95)04751-4
[2]
Korun, M., Martinčič, R. and Merkan, M. (1996) Determination of the Activities in Inhomogeneous Samples by Gamma Spectrometry Using Energy-Dependent Self-Absorption. Nuclear Instruments and Methods in Physics Research Section A, 369, 681-683. https://doi.org/10.1016/S0168-9002(96)80075-1
[3]
Gharbi, F. (2011) Inhomogeneity Effects on HPGe Gamma Spectrometry Detection Efficiency Using Monte Carlo Technique. Nuclear Instruments and Methods in Physics Research Section A, 654, 266-271. https://doi.org/10.1016/j.nima.2011.06.055
[4]
IEEE (The Institute of Electrical and Electronics Engineers) (1978) ANSI/IEEE Standard 680-1978: IEEE Standard Techniques for Determination of Germanium Semiconductor Detector Gamma-Ray Efficiency Using a Standard Marinelli (Reentrant) Beaker Geometry. The Institute of Electrical and Electronics Engineers, New York. https://doi.org/10.1109/IEEESTD.1978.7434538
[5]
Zamzamian, S.M., Hosseini, S.A., Feghhi, S.A. and Samadfam, M. (2020) Determining of the Optimized Dimensions of the Marinelli Beaker Containing Source with Inhomogeneous Emission Rate by Using Genetic Algorithm Coupled with MCNP and Determining Distribution Type by Neural Networks. Applied Radiation and Isotopes, 157, Article No. 109039. https://doi.org/10.1016/j.apradiso.2020.109039
[6]
Bronson, F. (2010) How Well Does a Gamma Spectroscopy Calibration with a Uniform Density Matrix Represent a Sample with a Non-Uniform Matrix? 56th Annual Radiobioassay and Radiochemical Measurements Conference, Richland, 25-28 October 2010.
[7]
Semkow, T.M., Bradt, C.J., Beach, S.E., Haines, D.K., Khan, A.J., Bari, A., Torres, M.A., Marrantino, J.C., Syed, U.-F., Kitto, M.E., Hoffman, T.J. and Curtis, P. (2015) Calibration of Ge Gamma-Ray Spectrometers for Complex Sample Geometries and Matrices. Nuclear Instruments and Methods in Physics Research Section A, 799, 105-113. https://doi.org/10.1016/j.nima.2015.07.064
[8]
Adams, C.E., Farlow, N.H. and Schell, W.R. (1960) The Compositions, Structures and Origin of Radioactive Fall-Out Particles. Geochimica et Cosmochimica Acta, 18, 42-56. https://doi.org/10.1016/0016-7037(60)90016-8
[9]
Sandalls, F.J., Segal, M.G. and Victorova, N. (1993) Hot Particles from Chernobyl: A Review. Journal of Environmental Radioactivity, 18, 5-22. https://doi.org/10.1016/0265-931X(93)90063-D
[10]
Zheltonozhsky, V., Mück, K. and Bondarkov, M. (2001) Classification of Hot Particles from the Chernobyl Accident and Nuclear Weapons Detonations by Non-Destructive Methods Journal of Environmental Radioactivity, 57, 151-166. https://doi.org/10.1016/S0265-931X(01)00013-3
[11]
Igarashi, Y., Kogure, T., Kurihara, Y., Miura, H., Okumura, T., Satouf, Y., Takahashic, Y. and Yamaguchi, N. (2019) A Review of Cs-Bearing Microparticles in the Environment Emitted by the Fukushima Dai-ichi Nuclear Power Plant Accident. Journal of Environmental Radioactivity, 205-206, 101-118. https://doi.org/10.1016/j.jenvrad.2019.04.011
[12]
Futagami, F., Soliman, M., Takamiya, K., Sekimoto, S., Oki, Y., Kubota, T., Konno, M., Mizuno, S. and Ohtsuki, T. (2020) Isolation, Characterization and Source Analysis of Radiocaesium Micro-Particles in Soil Sample Collected from Vicinity of Fukushima Dai-ichi Nuclear Power Plant. Journal of Environmental Radioactivity, 223-224, Article ID: 106388. https://doi.org/10.1016/j.jenvrad.2020.106388
[13]
Ansoborlo, E. and Stather, J. (2000) Review of the Characterization of Hot Particles Released into the Environment and Pathways for Intake of Particles. Radiation Protection Dosimetry, 92, 139-143. https://doi.org/10.1093/oxfordjournals.rpd.a033259
[14]
Tcherkezian, V., Shkinev, V., Khitrov, L. and Kolesov, G. (1994) Experimental Approach to Chernobyl Hot Particles. Journal of Environmental Radioactivity, 22, 127-139. https://doi.org/10.1016/0265-931X(94)90018-3
[15]
Shevchenko, S.V. (2004) On the Uncertainty in Activity Measurements for Samples containing “Hot Particles”. Applied Radiation and Isotopes, 61, 1303-1306. https://doi.org/10.1016/j.apradiso.2004.02.022
[16]
Tian, Z., Ouyang, X., Liu, L., Ruan, J. and Liu, J. (2015) A Theoretical and Experimental Research on Detection Efficiency of HPGe Detector for Disc Source with Heterogeneous Distribution. Journal of Radioanalytical and Nuclear Chemistry, 304, 905-910. https://doi.org/10.1007/s10967-014-3907-2
[17]
Masson, O., Baeza, A., Bieringer, J., Brudecki, K., Bucci, S., Cappai, M., et al. (2011) Tracking of Airborne Radionuclides from the Damaged Fukushima Dai-Ichi Nuclear Reactors by European Networks. Environmental Science & Technologyl, 45, 7670-7677. https://doi.org/10.1021/es2017158
[18]
Kaltofen, M. and Gundersen, A. (2017) Radioactively-Hot Particles Detected in Dusts and Soils from Northern Japan by Combination of Gamma Spectrometry, Autoradiography, and SEM/EDS Analysis and Implications in Radiation Risk Assessment. Science of the Total Environment, 607-608, 1065-1072. https://doi.org/10.1016/j.scitotenv.2017.07.091
[19]
Kitto, M.E., Menia, T.A., Haines, D.K., Beach, S.E., Bradt, C.J., Fielman, E.M., Syed, U.-F., Semkow, T.M., Bari, A. and Khan, A.J. (2013) Airborne Gamma-Ray Emitters from Fukushima Detected in New York State. Journal of Radioanalytical and Nuclear Chemistry, 296, 49-56. https://doi.org/10.1007/s10967-012-2043-0
[20]
Bondarkov, M.D., Zheltonozhsky, V.A., Zheltonozhskaya, M.V., Kulich, N.V., Maksimenko, A.M., Farfán, E.B., Jannik, G.T. and Marra, J.C. (2011) Assessment of the Radionuclide Composition of “Hot Particles” Sampled in the Chernobyl Nuclear Power Plant Fourth Reactor Unit. Health Physics, 101, 368-374. https://doi.org/10.1097/HP.0b013e31820dbc53
[21]
Nageldinger, G., Flowers, A. and Entwistle, J. (1998) A New Mechanism for Hot Particle Development in Soil Following Ionic Contamination with Radiocesium. Health Physics, 75, 646-647. https://doi.org/10.1097/00004032-199812000-00009
[22]
Charles, M.W. (1991) The Hot Particle Problem. Radiation Protection Dosimetry, 39, 39-47.
[23]
Byrnes, I., Lind, O.C., Hansen, E.L., Janssens, K. and Salbu, B. (2020) Characterization of Radioactive Particles from the Dounreay Nuclear Reprocessing Facility. Science of the Total Environment, 727, Article ID: 138488. https://doi.org/10.1016/j.scitotenv.2020.138488
[24]
EPA (Environmental Protection Agency) (2009) Radiological Laboratory Sample Analysis Guide for Incidents of National Significance—Radionuclides in Air. US Environmental Protection Agency, Report EPA 402-R-09-007, National Air and Radiation Environmental Laboratory, Montgomery, AL.
[25]
Zeissler, C.J., Lindstrom, R.M. and McKinley, J.P. (2001) Radioactive Particle Analysis by Digital Radiography. Journal of Radioanalytical and Nuclear Chemistry, 248, 407-412. https://doi.org/10.1023/A:1010640411441
[26]
Dung, T.Q. (1998) Some Theoretical Results of Gamma Techniques for Measuring large Samples. Nuclear Instruments and Methods in Physics Research Section A, 416, 505-515. https://doi.org/10.1016/S0168-9002(98)00622-6
[27]
Krings, T. and Mauerhofer, E. (2011) Reconstruction of the Activity of Point Sources for the Accurate Characterization of Nuclear Waste Drums by Segmented Gamma Scanning. Applied Radiation and Isotopes, 69, 880-889. https://doi.org/10.1016/j.apradiso.2011.02.009
[28]
Stanga, D. and Gurau, D. (2012) A New Approach in Gamma-Rays Canning of Rotating Drums Containing Radioactive Waste. Applied Radiation and Isotopes, 70, 2149-2153. https://doi.org/10.1016/j.apradiso.2012.02.085
[29]
Wang, K., Li, Z. and Feng, W. (2014) Reconstruction of Finer Voxel Grid Transmission Images in Tomographic Gamma Scanning. Nuclear Instruments and Methods in Physics Research Section A, 755, 28-31. https://doi.org/10.1016/j.nima.2014.04.046
[30]
Glavič-Cindro, D., Korun, M., Vodenik, B. and Zorko, B. (2015) Activity Measurements of Barrels Filled with Radioactive Waste. Journal of Radioanalytical and Nuclear Chemistry, 304, 145-150. https://doi.org/10.1007/s10967-014-3666-0
[31]
Maxwell, S.L., Culligan, B.K., Kelsey-Wall, A. and Shaw, P.J. (2012) Rapid Determination of Actinides in Emergency Food Samples. Journal of Radioanalytical and Nuclear Chemistry, 292, 339-347. https://doi.org/10.1007/s10967-011-1411-5
[32]
Parekh, P.P., Semkow, T.M., Torres, M.A., Haines, D.K., Cooper, J.M., Rosenberg, P.M. and Kitto, M.E. (2006) Radioactivity in Trinitite Six Decades Later. Journal of Environmental Radioactivity, 85, 103-120. https://doi.org/10.1016/j.jenvrad.2005.01.017
[33]
Nishikawa, K., Bari, A., Khan, A.J., Li, X., Menia, T., Semkow, T.M., Lin, Z. and Healey, S. (2017) Homogenization of Food Samples for Gamma Spectrometry Using Tetramethylammonium Hydroxide and Enzymatic Digestion. Journal of Radioanalytical and Nuclear Chemistry, 314, 859-870. https://doi.org/10.1007/s10967-017-5434-4
[34]
Nishikawa, K., Bari, A., Khan, A.J., Li, X., Menia, T. and Semkow, T.M. (2018) Homogenization of Food Samples for Gamma Spectrometry Using Protease. Journal of Radioanalytical and Nuclear Chemistry, 318, 401-406. https://doi.org/10.1007/s10967-018-6065-0
[35]
Bunzl, K. (1997) Probability for Detecting Hot Particles in Environmental Samples by Sample Splitting. The Analyst, 122, 653-656. https://doi.org/10.1039/A700252A
[36]
Nageldinger, G., Flowers, A., Henry, B. and Postak, J. (1998) Hot Particle Detection Using Uncertainties in Activity Measurements of Soil. Health Physics, 74, 472-477. https://doi.org/10.1097/00004032-199804000-00009
[37]
Bunzl, K. (1998) Detection of the Radioactive Hot Particles in Environmental Samples by Repeated Mixing. Applied Radiation and Isotopes, 49, 1625-1631. https://doi.org/10.1016/S0969-8043(98)00002-5
[38]
Kashparov, V.A., Yoshchenko, V.I., Levtchuk, S.E., Tschiersch, J. and Wagenpfeil, F. (2000) Application of the Method of Repeated Mixing to Nonuniformity Contaminated Bulky Samples. Journal of Radioanalytical and Nuclear Chemistry, 246, 165-172. https://doi.org/10.1023/A:1006738727056
[39]
Sima, O., Arnold, D. and Dovlete, C. (2001) GESPECOR: A Versatile Tool in Gamma-Ray Spectrometry. Journal of Radioanalytical and Nuclear Chemistry, 248, 359-364. https://doi.org/10.1023/A:1010619806898
[40]
Sima, O. (2012) Efficiency Calculation of Gamma Detectors by Monte Carlo Methods. In: Encyclopedia of Analytical Chemistry, Nuclear Methods, J. Wiley & Sons, New York, 1-37. https://doi.org/10.1002/9780470027318.a9142
[41]
Åbro, E., Khoryakov, V.A., Johansen, G.A. and Kocbach, L. (1999) Determination of Void Fraction and Flow Regime Using a Neural Network Trained on Simulated Data Based on Gamma-Ray Densitometry. Measurement Science and Technology, 10, 619-630. https://doi.org/10.1088/0957-0233/10/7/308
[42]
El Abd, A. (2014) Intercomparison of Gamma Ray Scattering and Transmission Techniques for Gas Volume Fraction Measurements in Two Phase Pipe Flow. Nuclear Instruments and Methods in Physics Research Section A, 735, 260-266. https://doi.org/10.1016/j.nima.2013.09.047
[43]
Roshani, G.H., Nazemi, E. and Feghhi, S.A.H. (2016) Investigation of Using 60Co Source and One Detector for Determining the Flow Regime and Void Fraction in Gas-Liquid Two-Phase Flows. Flow Measurement and Instrumentation, 50, 73-79. https://doi.org/10.1016/j.flowmeasinst.2016.06.013
[44]
Frandes, M., Timar, B. and Lungeanu, D. (2016) Image Reconstruction Techniques for Compton Scattering Based Imaging: An Overview. Current Medical Imaging Reviews, 12, 95-105. https://doi.org/10.2174/1573405612666160128233916
[45]
Korun, M. (2004) Measurement of Peak and Total Efficiencies of Low-Energy Gamma-Ray Detectors with Sources Emitting Photons in Cascade. Applied Radiation and Isotopes, 60, 207-211. https://doi.org/10.1016/j.apradiso.2003.11.018
[46]
Semkow, T.M., Mehmood, G., Parekh, P.P. and Virgil, M. (1990) Coincidence Summing in Gamma-Ray Spectroscopy. Nuclear Instruments and Methods in Physics Research Section A, 290, 437-444. https://doi.org/10.1016/0168-9002(90)90561-J
[47]
Korun, M. (2001) Measurement of the Total-to-Peak Ratio of a Low-Energy Germanium Gamma-Ray Detector. Nuclear Instruments and Methods in Physics Research Section A, 457, 245-252. https://doi.org/10.1016/S0168-9002(00)00745-2
[48]
Kolotov, V.P., Atrashkevich, V.V. and Gelsema, S.J. (1996) Estimation of True Coincidence Corrections for Voluminous Sources. Journal of Radioanalytical and Nuclear Chemistry, 210, 183-196. https://doi.org/10.1007/BF02055417
[49]
Strom, E. and Israel, H.I. (1970) Photon Cross Sections from 1 keV to 100 MeV for Elements Z = 1 to Z = 100. Atomic Data and Nuclear Data Tables, 7, 565-681. https://doi.org/10.1016/S0092-640X(70)80017-1
[50]
Wickens, T.D. (2002) Elementary Signal Detection Theory. Oxford University Press, New York. https://doi.org/10.1093/acprof:oso/9780195092509.001.0001
