1
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Stanga D, Gurau D, Done L, Luca A. A novel virtual point detector model for high purity germanium detectors. Appl Radiat Isot 2022; 181:110107. [DOI: 10.1016/j.apradiso.2022.110107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 12/14/2021] [Accepted: 01/10/2022] [Indexed: 12/01/2022]
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2
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Lee JH, Byun JI. IN-SITU GAMMA-RAY SPECTROMETRY FOR RADIOACTIVITY ANALYSIS OF SOIL USING NaI(Tl) AND LaBr3(Ce) DETECTORS. RADIATION PROTECTION DOSIMETRY 2019; 187:300-309. [PMID: 31268526 DOI: 10.1093/rpd/ncz165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/04/2019] [Accepted: 06/24/2019] [Indexed: 06/09/2023]
Abstract
In this study, the full energy peak count rates to radioactivity conversion factors of 3″Ø × 3″ NaI(Tl) and 2″Ø × 2″ LaBr3(Ce) detectors for radioactivity analysis in the soil were determined on site using a semi-empirical method with point-like gamma-ray sources. To validate the conversion factors derived for the detectors, in-situ gamma-ray measurements were performed in wide open fields with almost flat surface and compared with the sampling analysis for the radioactivity of U-series, Th-series, and 40K in the soil. As a result, radioactivity concentrations of 40K, 208Tl and 214Bi by in-situ and laboratory measurements agreed well with each other within 5%, and the MDAs for artificial radionuclides were estimated under the condition of fresh deposition considering a radiation emergency situation.
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Affiliation(s)
- Jun-Ho Lee
- University of Science and Technology, 217 Gajeong-ro Yuseong-gu, Daejeon, Republic of Korea
| | - Jong-In Byun
- Korea Institute of Nuclear and Safety, 62 Gwahak-ro Yuseong-gu, Daejeon, Republic of Korea
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3
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Xiong J, Han J, Tian J, Liu Y, Xi Z, Du W, Wu X, Hu S, Jiang T, Wang X. Simulation of irradiation uniformity for polyethylene and polypropylene in various high energy fields. Radiat Phys Chem Oxf Engl 1993 2018. [DOI: 10.1016/j.radphyschem.2018.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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4
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Mrdja D, Bikit K, Forkapic S, Bikit I, Slivka J, Hansman J. Improvement of in-situ gamma spectrometry methods by Monte-Carlo simulations. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2018; 188:23-29. [PMID: 29132981 DOI: 10.1016/j.jenvrad.2017.11.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/03/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
Performing in-situ measurements of gamma radiation originating from soil requires adequate detection efficiency curves, which can be obtained by Monte-Carlo simulations. In simulations, soil density of 1.046 g/cm3 was used, with the following elemental composition of soil in which gamma radiation was generated: O - 47%, Si -35%, Al - 8%, Fe - 3.9%, C - 2.1%, Ca - 1.4%, K - 1.3%, N - 0.6%, Mg - 0.6%, N - 0.1%. Soil matrix was represented by cylindrical volume of 1.5 m diameter and 0.5m thickness, while germanium detector was placed at 1 m height above the soil. The simulated gamma spectrum, originated from K-40, as well as from members of Th-232 chain, and daughters of Ra-226, was obtained. Homogeneous distribution of various radionuclides (Ra-226, Th-232, K-40) in soil matrix is considered in this work. Gamma spectra obtained in simulations were analyzed, and together with simulated detection efficiency data they provide comparison with real experimental measurements and practical application of results derived by Monte-Carlo simulations. As a result of this work, the corresponding detection efficiency curve for HPGe detector was obtained, which can be applied for in-situ measurements of radionuclide concentration in soil, assuming uniform radionuclide distribution. In order to validate our simulation results regarding detection efficiency, we performed in-situ measurements of soil radioactivity and compared the obtained activity concentrations with laboratory measurements. We found a good agreement, within activity concentration uncertainty, between in-situ measurement results and average values of activity concentrations obtained by laboratory measurements.
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Affiliation(s)
- Dusan Mrdja
- Department of Physics, Faculty of Sciences, University of Novi Sad, Serbia
| | - Kristina Bikit
- Department of Physics, Faculty of Sciences, University of Novi Sad, Serbia.
| | - Sofija Forkapic
- Department of Physics, Faculty of Sciences, University of Novi Sad, Serbia
| | - Istvan Bikit
- Department of Physics, Faculty of Sciences, University of Novi Sad, Serbia
| | - Jaroslav Slivka
- Department of Physics, Faculty of Sciences, University of Novi Sad, Serbia
| | - Jan Hansman
- Department of Physics, Faculty of Sciences, University of Novi Sad, Serbia
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5
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Ramebäck H, Söderström C, Granström M, Jonsson S, Kastlander J, Nylén T, Ågren G. Measurements of 106Ru in Sweden during the autumn 2017: Gamma-ray spectrometric measurements of air filters, precipitation and soil samples, and in situ gamma-ray spectrometry measurement. Appl Radiat Isot 2018; 140:179-184. [PMID: 30031285 DOI: 10.1016/j.apradiso.2018.07.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 07/06/2018] [Accepted: 07/06/2018] [Indexed: 10/28/2022]
Abstract
During the last days of September to the first days of October in 2017, a unique detection of 106Ru was observed in air filters sampled at different locations in Sweden via the national air monitoring network. Furthermore, measurements of precipitation also showed the presence of 106Ru. This initiated soil sampling and in situ gamma-ray spectrometry at one of the locations.
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Affiliation(s)
- H Ramebäck
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden; Chalmers University of Technology, Department of Chemistry and Chemical Engineering Nuclear Chemistry, SE-412 96 Göteborg, Sweden.
| | - C Söderström
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
| | - M Granström
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
| | - S Jonsson
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
| | - J Kastlander
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
| | - T Nylén
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
| | - G Ågren
- Swedish Defence Research Agency (FOI), Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
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6
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Persson L, Boson J, Nylén T, Ramebäck H. Application of a Monte Carlo method to the uncertainty assessment in in situ gamma-ray spectrometry. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2018; 187:1-7. [PMID: 29459254 DOI: 10.1016/j.jenvrad.2018.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 02/02/2018] [Accepted: 02/05/2018] [Indexed: 06/08/2023]
Abstract
In situ gamma-ray spectrometry has since the introduction of portable germanium detectors been a widely used method for the assessment of radionuclide ground deposition activity levels. It is, however, a method that is most often associated with fairly large and, more important, poorly known combined measurement uncertainties. In this work an uncertainty analysis of in situ gamma ray spectrometry in accordance with the Guide to the Expression of Uncertainty in Measurements is presented. The uncertainty analysis takes into account uncertainty contributions from the calibration of the detector system, the assumed activity distribution in soil, soil density, detector height and air density. As a result, measurement results from in situ gamma spectrometry will serve as a better basis for decision-making in e.g. radiological emergencies.
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Affiliation(s)
- Leif Persson
- Swedish Defence Research Agency, FOI CBRN Defence and Security, SE-901 82 Umeå, Sweden; Department of Mathematics and Mathematical Statistics, Umeå University, SE-90187 Umeå, Sweden
| | - Jonas Boson
- Swedish Radiation Safety Authority, SSM, SE-171 16 Stockholm, Sweden
| | - Torbjörn Nylén
- Swedish Defence Research Agency, FOI CBRN Defence and Security, SE-901 82 Umeå, Sweden
| | - Henrik Ramebäck
- Swedish Defence Research Agency, FOI CBRN Defence and Security, SE-901 82 Umeå, Sweden; Chalmers University of Technology, Department of Chemistry and Chemical Engineering, SE-412 96 Göteborg, Sweden.
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7
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Bochud FO, Laedermann JP, Baechler S, Bailat C. CONVERTING SPECIFIC ACTIVITY INTO AMBIENT DOSE EQUIVALENT: UPDATED COEFFICIENTS FOR IN SITU GAMMA SPECTROMETRY. RADIATION PROTECTION DOSIMETRY 2017; 174:167-174. [PMID: 27311733 DOI: 10.1093/rpd/ncw130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 05/06/2016] [Indexed: 06/06/2023]
Abstract
In situ gamma spectrometry is a valuable tool to assess the radionuclides released in the environment and the associated dose. This requires prior establishment of coefficients allowing the conversion of the specific activity into ambient equivalent dose. The aim of this work is to calculate updated conversion factors for monoenergetic photons and for a series of radionuclides of interest. The calculation was performed using the Monte Carlo (MC) method, the GEANT4 MC code, various activity distribution models and up-to-date nuclear decay data. A new set of conversion factors is established in the energy range extending from <100 keV to 8.5 MeV. The coefficients calculated in this work were compared to the data published in the literature.
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Affiliation(s)
- F O Bochud
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV), Switzerland
| | - J-P Laedermann
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV), Switzerland
| | - S Baechler
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV), Switzerland
| | - C Bailat
- Institute of Radiation Physics (IRA), Lausanne University Hospital (CHUV), Switzerland
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8
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Androulakaki EG, Tsabaris C, Eleftheriou G, Kokkoris M, Patiris DL, Pappa FK, Vlastou R. Efficiency calibration for in situ γ-ray measurements on the seabed using Monte Carlo simulations: Application in two different marine environments. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 164:47-59. [PMID: 27420593 DOI: 10.1016/j.jenvrad.2016.06.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 06/02/2016] [Accepted: 06/20/2016] [Indexed: 06/06/2023]
Abstract
A new approach for calibrating an in situ detection system for measurements in marine sediments has been developed. The efficiency calibration was deduced on full spectral range by Monte Carlo simulations (MCNP5 code) considering a close detector-seabed geometry set-up. Moreover, the influence of the detection efficiency with respect to the variations of the sediment geological characteristics was studied through Monte Carlo simulations. The results of the theoretical approach were compared with experimental calculations in two different real test cases, yielding a satisfactory agreement (up to 10% and 20% for sites 1 and 2 respectively) in the energy range from 351 keV to 2614 keV. For the experimental measurements, the in situ detection system KATERINA was deployed both in the seawater and on the seabed in two different marine environments. The experimental determinations of the detection efficiency were performed by utilizing the acquired data of the deployments, along with additional necessary laboratory measurements. The adopted approach and the obtained results are discussed.
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Affiliation(s)
- E G Androulakaki
- Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece; National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece.
| | - C Tsabaris
- Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece
| | - G Eleftheriou
- Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece; National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece
| | - M Kokkoris
- National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece
| | - D L Patiris
- Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece
| | - F K Pappa
- Hellenic Centre for Marine Research, Institute of Oceanography, P.O. Box 712, GR 19013, Anavyssos, Greece; National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece
| | - R Vlastou
- National Technical University of Athens, Department of Physics, Zografou Campus, GR 15780, Athens, Greece
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9
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Grozdov DS, Kolotov VP, Lavrukhin YE. Computation of full energy peak efficiency for nuclear power plant radioactive plume using remote scintillation gamma-ray spectrometry. Appl Radiat Isot 2016; 110:118-123. [PMID: 26774388 DOI: 10.1016/j.apradiso.2016.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 12/16/2015] [Accepted: 01/08/2016] [Indexed: 10/22/2022]
Abstract
A method of full energy peak efficiency estimation in the space around scintillation detector, including the presence of a collimator, has been developed. It is based on a mathematical convolution of the experimental results with the following data extrapolation. The efficiency data showed the average uncertainty less than 10%. Software to calculate integral efficiency for nuclear power plant plume was elaborated. The paper also provides results of nuclear power plant plume height estimation by analysis of the spectral data.
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Affiliation(s)
- D S Grozdov
- Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences, Kosigyna 19, 119991 Moscow, Russia.
| | - V P Kolotov
- Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences, Kosigyna 19, 119991 Moscow, Russia.
| | - Yu E Lavrukhin
- Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences, Kosigyna 19, 119991 Moscow, Russia
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10
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Chirosca A, Suvaila R, Sima O. Monte Carlo simulation by GEANT 4 and GESPECOR of in situ gamma-ray spectrometry measurements. Appl Radiat Isot 2013; 81:87-91. [DOI: 10.1016/j.apradiso.2013.03.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 03/09/2013] [Indexed: 11/26/2022]
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11
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Application of the Monte Carlo code DETEFF to efficiency calibrations for in situ gamma-ray spectrometry. Appl Radiat Isot 2012; 70:868-71. [DOI: 10.1016/j.apradiso.2012.01.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 01/10/2012] [Accepted: 01/20/2012] [Indexed: 11/20/2022]
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12
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Agrafiotis K, Karfopoulos KL, Anagnostakis MJ. Calibration of an in-situ BEGe detector using semi-empirical and Monte Carlo techniques. Appl Radiat Isot 2011; 69:1151-5. [PMID: 21193317 DOI: 10.1016/j.apradiso.2010.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 12/07/2010] [Accepted: 12/07/2010] [Indexed: 11/26/2022]
Abstract
In the case of a nuclear or radiological accident a rapid estimation of the qualitative and quantitative characteristics of the potential radioactive pollution is needed. For aerial releases the radioactive pollutants are finally deposited on the ground forming a surface source. In this case, in-situ γ-ray spectrometry is a powerful tool for the determination of ground pollution. In this work, the procedure followed at the Nuclear Engineering Department of the National Technical University of Athens (NED-NTUA) for the calibration of an in-situ Broad Energy Germanium (BEGe) detector, for the determination of gamma-emitting radionuclides deposited on the ground surface, is presented. BEGe detectors due to their technical characteristics are suitable for the analysis of photons in a wide energy region. Two different techniques were applied for the full-energy peak efficiency calibration of the BEGe detector in the energy region 60-1600 keV: Full-energy peak efficiencies determined using the two methods agree within statistical uncertainties.
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Affiliation(s)
- K Agrafiotis
- Nuclear Engineering Department, School of Mechanical Engineering, National Technical University of Athens, 15780 Athens, Greece
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13
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Boson J, Plamboeck AH, Ramebäck H, Agren G, Johansson L. Evaluation of Monte Carlo-based calibrations of HPGe detectors for in situ gamma-ray spectrometry. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2009; 100:935-940. [PMID: 19604609 DOI: 10.1016/j.jenvrad.2009.06.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 05/25/2009] [Accepted: 06/04/2009] [Indexed: 05/28/2023]
Abstract
The aim of this work was to evaluate the use of Monte Carlo-based calibrations for in situ gamma-ray spectrometry. We have performed in situ measurements at five different sites in Sweden using HPGe detectors to determine ground deposition activity levels of (137)Cs from the 1986 Chernobyl accident. Monte Carlo-calculated efficiency calibration factors were compared with corresponding values calculated using a more traditional semi-empirical method. In addition, results for the activity ground deposition were also compared with activity densities found in soil samples. In order to facilitate meaningful comparisons between the different types of results, the combined standard uncertainty of in situ measurements was assessed for both calibration methods. Good agreement, both between the two calibration methods, and between in situ measurements and soil samples, was found at all five sites. Uncertainties in in situ measurements for the given measurement conditions, about 20 years after the fallout occurred, were found to be in the range 15-20% (with a coverage factor k=1, i.e. with a confidence interval of about 68%).
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Affiliation(s)
- Jonas Boson
- Swedish Defence Research Agency, FOI CBRN Defence and Security, SE-901 82 Umeå, Sweden.
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14
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Boson J, Johansson L, Ramebäck H, Agren G. Uncertainty in HPGe detector calibrations for in situ gamma-ray spectrometry. RADIATION PROTECTION DOSIMETRY 2009; 134:122-129. [PMID: 19429646 DOI: 10.1093/rpd/ncp079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Semi-empirical methods are often used for efficiency calibrations of in situ gamma-ray spectrometry measurements with high-purity germanium detectors. The intrinsic detector efficiency is experimentally determined for different photon energies and angles of incidence, and a suitable expression for the efficiency is fitted to empirical data. In this work, the combined standard uncertainty of such an efficiency function for two detectors was assessed. The uncertainties in individual efficiency measurements were found to be about 1.9 and 3.1% (with a coverage factor k = 1, i.e. with a confidence interval of about 68%) for the two detectors. The main contributions to these uncertainties were found to originate from uncertainties in source-to-detector distance, source activity and full-energy peak count rate. The standard uncertainties of the fitted functions were found to be somewhat higher than the uncertainty of individual data points, i.e. 5.2 and 8.1% (k = 1). With the introduction of a new expression for the detector efficiency, these uncertainties were reduced to 3.7 and 4.2%, i.e. with up to a factor of two. Note that this work only addresses the uncertainty in the determination of intrinsic detector efficiency.
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Affiliation(s)
- Jonas Boson
- Swedish Defence Research Agency, FOI CBRN Defence and Security, SE-901 82 Umeå, Sweden.
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