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Gupta A, Shareef M, Twisha M, Bhattacharjee S, Mukherjee G, Nayak SS, Basu S, Dasgupta S, Datta J, Bhattacharyya S, Mukherjee A. True coincidence summing correction for a BEGe detector in close geometry measurements. Appl Radiat Isot 2023; 200:110966. [PMID: 37566947 DOI: 10.1016/j.apradiso.2023.110966] [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: 04/12/2023] [Revised: 07/06/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023]
Abstract
The true coincidence summing correction factor for a Broad Energy Germanium detector has been calculated at far and close geometry set-up using radioactive γ-ray sources. The correction factors were calculated using both experimental and analytical methods. Geant4 simulation was done to calculate the full-energy peak and total efficiencies of the detector. Standard, as well as fabricated mono-energetic γ-ray sources, were used for the γ-ray efficiency measurements. The simulated efficiencies of mono-energetic γ-ray sources were matched to the experimental γ-ray efficiencies by optimizing the detector parameters. The same parameters were used to obtain the full-energy peak and total efficiencies for γ-rays of current interest. Analytical and experimental correction factors were found to agree well with each other. The coincidence summing effect is found to be significant for source-to-detector distances less than 5 cm.
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Affiliation(s)
- Ashish Gupta
- Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata, 700064, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai, 400094, India
| | - M Shareef
- Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - Munmun Twisha
- Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata, 700064, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai, 400094, India
| | - Saikat Bhattacharjee
- Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata, 700064, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai, 400094, India
| | - Gopal Mukherjee
- Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - Satya Samiran Nayak
- Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - Sansaptak Basu
- Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - S Dasgupta
- Analytical Chemistry Division, Bhabha Atomic Research Centre, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - J Datta
- Analytical Chemistry Division, Bhabha Atomic Research Centre, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - S Bhattacharyya
- Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700064, India
| | - A Mukherjee
- Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata, 700064, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai, 400094, India.
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Dhibar M, Mankad D, Mazumdar I, Kumar GA. Efficiency calibration and coincidence summing correction for a large volume (946cm 3) LaBr 3(Ce) detector: GEANT4 simulations and experimental measurements. Appl Radiat Isot 2016; 118:32-37. [PMID: 27587372 DOI: 10.1016/j.apradiso.2016.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 08/18/2016] [Accepted: 08/18/2016] [Indexed: 11/18/2022]
Abstract
The paper describes the studies on efficiency calibration and coincidence summing correction for a 3.5″×6″ cylindrical LaBr3(Ce)detector. GEANT4 simulations were made with point sources, namely, 60Co, 94Nb, 24Na, 46Sc and 22Na. The simulated efficiencies, extracted using 60Co, 94Nb, 24Na and 46Sc that emit coincident gamma rays with same decay intensities, were corrected for coincidence summing by applying the method proposed by Vidmar et al. (2003). The method was applied, for the first time, for correcting the simulated efficiencies extracted using 22Na that emits coincident gamma rays with different decay intensities. The measured results obtained using 60Co and 22Na were found to be in good agreement with simulated results.
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Affiliation(s)
- M Dhibar
- Dept. of Physics, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - D Mankad
- Dept. of Mechanical and Industrial Engineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - I Mazumdar
- Dept. of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - G Anil Kumar
- Dept. of Physics, Indian Institute of Technology Roorkee, Roorkee 247667, India.
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Zhou Q, Wang X, Tuo F, Han Y, Ikeuchi Y, Yang J, Xu C, Zhang J, Li W, Zhang Q, Su X. Intercomparison of γ-spectrometry analysis of radionuclides between China and Japan in 2012-2013. Appl Radiat Isot 2015; 105:244-248. [PMID: 26343339 DOI: 10.1016/j.apradiso.2015.08.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 08/17/2015] [Accepted: 08/17/2015] [Indexed: 11/28/2022]
Abstract
An intercomparison of γ-spectrometry measurement and analysis was organized by the Japan Chemical Analysis Center (JCAC), the National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention (NIRP, China CDC), and the Radiation Monitoring Technical Center of Ministry of Environmental Protection, Chinese (RMTC). The main objective of this study was to assess the γ-spectrometry measurement and analysis technology. The JCAC completed the collection and preparation of soil and powdered rice samples. Three laboratories compared the measurement of seven radionuclides that included two samples of (214)Pb, (214)Bi, (208)Tl, (228)Ac, (40)K, (137)Cs, and (134)Cs with γ-spectrometry. During the studies conducted at the laboratory, the calculated value En was found to be the total uncertainty data of the reported activity. Except (134)Cs in powdered rice sample, the calculated En between each of the two laboratories was <1. The measurement results are acceptable except (134)Cs; therefore, measurement results in the three laboratories were consistent within a certain range except in the case of (134)Cs. Although there is a need to improve the accuracy of measurements and analysis of (134)Cs, an intercomparison was conducted of the tested levels on radionuclide analyzed in the three laboratories.
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Affiliation(s)
- Qiang Zhou
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Xiaoqiang Wang
- Hospital for Occupational Diseases Control of Shenzhen City, 70 Guiyuanbei Street, Shenzhen 518001, China
| | - Fei Tuo
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Yanqing Han
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Yoshihiro Ikeuchi
- Japan Chemical Analysis Center, 295-3, Sanno-cho, Inage-ku, Chiba 263-0002, Japan
| | - Jia Yang
- Radiation Monitoring Technical Center of Ministry of Environmental Protection, Chinese, 306 Wenyi Road, Hangzhou 310012, China
| | - Cuihua Xu
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Jing Zhang
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Wenhong Li
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Qing Zhang
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China
| | - Xu Su
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Key Laboratory of Radiological Protection and Nuclear Emergency, 2 Xinkang Street Deshengmenwai, Beijing 100088, China.
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McNamara AL, Heijnis H, Fierro D, Reinhard MI. The determination of the efficiency of a Compton suppressed HPGe detector using Monte Carlo simulations. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2012; 106:1-7. [PMID: 22304994 DOI: 10.1016/j.jenvrad.2011.10.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 10/21/2011] [Accepted: 10/22/2011] [Indexed: 05/31/2023]
Abstract
A Compton suppressed high-purity germanium (HPGe) detector is well suited to the analysis of low levels of radioactivity in environmental samples. The difference in geometry, density and composition of environmental calibration standards (e.g. soil) can contribute to excessive experimental uncertainty to the measured efficiency curve. Furthermore multiple detectors, like those used in a Compton suppressed system, can add complexities to the calibration process. Monte Carlo simulations can be a powerful complement in calibrating these types of detector systems, provided enough physical information on the system is known. A full detector model using the Geant4 simulation toolkit is presented and the system is modelled in both the suppressed and unsuppressed mode of operation. The full energy peak efficiencies of radionuclides from a standard source sample is calculated and compared to experimental measurements. The experimental results agree relatively well with the simulated values (within ∼5 - 20%). The simulations show that coincidence losses in the Compton suppression system can cause radionuclide specific effects on the detector efficiency, especially in the Compton suppressed mode of the detector. Additionally since low energy photons are more sensitive to small inaccuracies in the computational detector model than high energy photons, large discrepancies may occur at energies lower than ∼100 keV.
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Affiliation(s)
- A L McNamara
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW Australia.
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