1
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Wen ZW, Song SY, Xu JK, Gong YW, Huang YX, Ran JL, Tang XQ, Chen ZQ, Li Y, Luo P. DEVELOPMENT OF AN EXTENDED-RANGE BONNER SPHERE SPECTROMETER FOR CHINA INITIATIVE ACCELERATOR-DRIVEN SYSTEM. RADIATION PROTECTION DOSIMETRY 2023; 199:152-163. [PMID: 36484699 DOI: 10.1093/rpd/ncac251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 09/20/2022] [Accepted: 11/04/2022] [Indexed: 06/17/2023]
Abstract
To measure the extended-range neutron spectra and calibrate the extended-range neutron dosemeters of the China initiative Accelerator-Driven System (CiADS), an Extended-range Bonner Sphere Spectrometer (EBSS) has been developed. The EBSS was designed based on the PHITS codes, investigating various combinations of materials and diameters of the neutron moderators and the neutron multipliers for extended-range neutrons. Finally, seven polyethylene-only spheres and seven extended-range spheres were selected and subsequently built. The neutron multipliers of the extended-range spheres embedded concentric shells of lead, copper and tungsten. The response functions of the EBSS were analyzed and experimentally validated. It was subsequently tested with 252Cf neutron source and cosmic ray neutron source. The results demonstrate that the EBSS is capable of accurately measuring neutron spectra.
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Affiliation(s)
- Z W Wen
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - S Y Song
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - J K Xu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Nuclear Science and Engineering, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Y W Gong
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Nuclear Science and Engineering, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Y X Huang
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - J L Ran
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - X Q Tang
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Nuclear Science and Engineering, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Z Q Chen
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Nuclear Science and Engineering, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Y Li
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - P Luo
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Nuclear Science and Engineering, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
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2
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Nguyen DQ, Kim H, Phan QV, Nguyen DT, Nam UW, Park WK, Sohn J, Choi YJ, Kim S, Youn S, Ye SJ. Measuring and unfolding fast neutron spectra using solution-grown trans-stilbene scintillation detector. NUCLEAR ENGINEERING AND TECHNOLOGY 2022. [DOI: 10.1016/j.net.2022.10.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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3
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Yu Q, Shen F, Yuan L, Lin L, Hu Z, Zhou B, Liang T. Physical design of an Atmospheric Neutron Irradiation Spectrometer at China Spallation Neutron Source. NUCLEAR ENGINEERING AND DESIGN 2022. [DOI: 10.1016/j.nucengdes.2021.111579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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4
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Roy A, Sarkar R, Lee C. Extensive study of radiation dose on human body at aviation altitude through Monte Carlo simulation. LIFE SCIENCES IN SPACE RESEARCH 2021; 31:1-13. [PMID: 34689941 DOI: 10.1016/j.lssr.2021.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
The diverse near-Earth radiation environment due to cosmic rays and solar radiation has direct impact on human civilization. In the present and upcoming era of increasing air transfer, it is important to have precise idea of radiation dose effects on human body during air travel. Here, we calculate the radiation dose on the human body at the aviation altitude, also considering the shielding effect of the aircraft structure, using Monte Carlo simulation technique based on Geant4 toolkit. We consider proper 3D mathematical model of the atmosphere and geomagnetic field, updated profile of the incoming particle flux due to cosmic rays and appropriate physics processes. We use quasi-realistic computational phantoms to replicate the human body (male/female) for the effective dose calculation and develop a simplified mathematical model of the aircraft (taking Boeing 777-200LR as reference) for the shielding study. We simulate the radiation environment at the flying altitude (at 10 km and considering geomagnetic latitude in the range of 45-50°), as well as at various locations inside the fuselage of the aircraft. Then, we calculate the dose rates in the different organs for both male and female phantoms, based on latest recommendations of International Commission on Radio logical Protection. This calculation shows that the sex-averaged effective dose rate in human phantom is 5.46 μSv/h, whereas, if we calculate weighted sum of equivalent dose contributions separately in female and male body: total weighted sum of equivalent dose rate received by the female phantom is 5.72 μSv/h and that by the male phantom is 5.20 μSv/h. From the simulation, we also calculate the numerous cosmogenic radionuclides produced inside the phantoms through activation or spallation processes which may induce long-term biological effects.
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Affiliation(s)
- Abhijit Roy
- Indian Centre for Space Physics, 43 Chalantika, Garia Station Rd., Kolkata 700084, W.B., India.
| | - Ritabrata Sarkar
- Indian Centre for Space Physics, 43 Chalantika, Garia Station Rd., Kolkata 700084, W.B., India.
| | - Choonsik Lee
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20852, USA.
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5
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Dawn S, Chatterjee S, Chakrabarty S, Mufti S, Bakshi A, Sapra B. Cosmic ray neutron spectrometry and dosimetry at High Altitude Research Laboratory, Gulmarg, Kashmir, India. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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6
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Liu H, Hou Y, Li H, Song Y, Hu L, Liang M. Cosmic-ray neutron fluxes and spectra at different altitudes based on Monte Carlo simulations. Appl Radiat Isot 2021; 175:109800. [PMID: 34144339 DOI: 10.1016/j.apradiso.2021.109800] [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: 09/14/2020] [Revised: 05/26/2021] [Accepted: 05/28/2021] [Indexed: 10/21/2022]
Abstract
Cosmic-ray neutrons (CRNs) account for about half of the radiation dose received by airline crews and passengers at aviation altitudes. CRNs also comprise important background radiation near the ground, which should be considered in neutron counts for the purpose of nuclear safeguarding and homeland security. In this study, simulations were conducted with the Geant4 toolkit to describe the air shower of cosmic rays. The latest experimental driving models for the atmosphere, geomagnetic field, and primary galactic cosmic rays were applied in these simulations. The simulation was validated by comparing the results with those measured on the NASA ER-2 aircraft. the CRN fluxes and spectra were calculated at altitudes ranging from one to tens of kilometers. We determined the characteristics of the CRN spectra and analyzed their dependency on the altitude. To consider their impact on the local environment, the CRNs near the ground were modeled with a specific equivalent approach, which allowed the simulations to be conducted with limited computer processing power. The parameters for the incident primary CRNs near the ground were calculated by simulating the cosmic ray air shower. The modeling dimensions were considered for the air and ground, and an appropriate approximation solution was obtained. The model near the ground was used to investigate the dependences of the CRN flux and spectrum on the soil moisture.
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Affiliation(s)
- Huilan Liu
- College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001, China
| | - Yingwei Hou
- College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001, China
| | - Hui Li
- College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001, China
| | - Yushou Song
- College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001, China.
| | - Liyuan Hu
- College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001, China
| | - Manchun Liang
- Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory of City Integrated Emergency Response Science, Beijing 100084, China
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7
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Haghparast M, Afkhami Ardekani M, Navaser M, Refahi S, Najafzadeh M, Ghaffari H, Masoumbeigi M. Assessment of background radiation levels in the southeast of Iran. Med J Islam Repub Iran 2020; 34:56. [PMID: 32934945 PMCID: PMC7481852 DOI: 10.34171/mjiri.34.56] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Indexed: 12/03/2022] Open
Abstract
Background: Measuring background radiation (BR) is highly important from different perspectives, especially from that of human health. This study was conducted to measure BR in the southeast of Iran.
Methods: BR was measured in Hormozgan and Sistan-Bluchestan provinces using portable Environmental Radiation Meter Type 6- 80 detector. The average value was used to calculate the absorbed dose rate and indoor annual effective dose (AED) from BR. In addition, excess lifetime cancer risk (ELCR) was evaluated.
Results: The results showed that the maximum and minimum absorbed dose rates were 71.9 and 34.2 nGy.h-1 in Abomoosa and Minab in Hormozgan province and 90.0 and 47.8 nGy.h-1 in Zahedan and Chabahar in Sistan-Bluchestan province, respectively. Data indicated that these areas had a lower BR level compared with the worldwide level. The ELCR from indoor AED was larger compared with the worldwide average of 0.29 × 10-3.
Conclusion: This study provided a reference for designing and developing specific regional surveys associated with the measurement of natural BR in the southeast of Iran.
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Affiliation(s)
- Mohammad Haghparast
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.,Department of Radiology, Faculty of Paramedicine, Hormozgan University of Medical Sciences, Bandar-Abbas, Iran
| | - Mahdieh Afkhami Ardekani
- Department of Radiology, Faculty of Paramedicine, Hormozgan University of Medical Sciences, Bandar-Abbas, Iran
| | - Mahmoud Navaser
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Soheila Refahi
- Department of Medical Physics, Faculty of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Milad Najafzadeh
- Department of Radiology, Faculty of Paramedicine, Hormozgan University of Medical Sciences, Bandar-Abbas, Iran
| | - Hamed Ghaffari
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mahboubeh Masoumbeigi
- Department of Medical Physics & Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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8
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Optimization of water-pumping-injection multi-homocentric sphere neutron spectrometer. SN APPLIED SCIENCES 2020. [DOI: 10.1007/s42452-020-2818-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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9
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The Impact of Dose Rate on DNA Double-Strand Break Formation and Repair in Human Lymphocytes Exposed to Fast Neutron Irradiation. Int J Mol Sci 2019; 20:ijms20215350. [PMID: 31661782 PMCID: PMC6862539 DOI: 10.3390/ijms20215350] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/16/2019] [Accepted: 10/19/2019] [Indexed: 12/12/2022] Open
Abstract
The lack of information on how biological systems respond to low-dose and low dose-rate exposures makes it difficult to accurately assess the carcinogenic risks. This is of critical importance to space radiation, which remains a serious concern for long-term manned space exploration. In this study, the γ-H2AX foci assay was used to follow DNA double-strand break (DSB) induction and repair following exposure to neutron irradiation, which is produced as secondary radiation in the space environment. Human lymphocytes were exposed to high dose-rate (HDR: 0.400 Gy/min) and low dose-rate (LDR: 0.015 Gy/min) p(66)/Be(40) neutrons. DNA DSB induction was investigated 30 min post exposure to neutron doses ranging from 0.125 to 2 Gy. Repair kinetics was studied at different time points after a 1 Gy neutron dose. Our results indicated that γ-H2AX foci formation was 40% higher at HDR exposure compared to LDR exposure. The maximum γ-H2AX foci levels decreased gradually to 1.65 ± 0.64 foci/cell (LDR) and 1.29 ± 0.45 (HDR) at 24 h postirradiation, remaining significantly higher than background levels. This illustrates a significant effect of dose rate on neutron-induced DNA damage. While no significant difference was observed in residual DNA damage after 24 h, the DSB repair half-life of LDR exposure was slower than that of HDR exposure. The results give a first indication that the dose rate should be taken into account for cancer risk estimations related to neutrons.
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10
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Woolf RS, Sinclair LE, Van Brabant RA, Harvey BJA, Phlips BF, Hutcheson AL, Jackson EG. Measurement of secondary cosmic-ray neutrons near the geomagnetic North Pole. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 198:189-199. [PMID: 30640033 DOI: 10.1016/j.jenvrad.2019.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 12/27/2018] [Accepted: 01/02/2019] [Indexed: 06/09/2023]
Abstract
The spectrum of cosmogenic neutrons at Earth's surface covers a wide energy range, from thermal to several GeV. The flux of secondary neutrons varies with latitude, elevation, solar activity, and nearby material, including ground moisture. We report the results from a campaign to measure count rates in neutron detectors responding to three different energy ranges conducted near the geomagnetic North Pole at CFS Alert, Nunavut, Canada (82.5°N, 62.5°W; vertical geomagnetic cutoff rigidity, RC = 0 GV) in June of 2016. In November 2016, we performed a follow-on measurement campaign in southern Canada at similar RC (1.5 GV) and elevations. We conducted these measurements, at varying elevation and ground moisture content, with unmoderated and moderated 3He detectors for thermal and epithermal-to-MeV sensitivity, and with EJ-299-33 pulse shape discrimination plastic scintillator detectors for fast neutrons. Background gamma rays were monitored with NaI(Tl) detectors. Using these data sets, we compared the measured count rates to a predictive model. This is the first ever data set taken from this location on Earth. We find that for the thermal and epithermal-to-MeV neutron measurements the predictive model and data are in good agreement, except at one location on rock-covered ground near 1 km elevation. The discrepancy at that location may be attributable to ground moisture variability. Other measurements, during this campaign and prior, support the assertion that ground moisture plays a critical role in determining neutron flux.
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Affiliation(s)
- Richard S Woolf
- Space Science Division, U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
| | - Laurel E Sinclair
- Natural Resources Canada, Government of Canada, 930 Carling Ave (CEF, Bldg 7, Observatory Cr.), Ottawa, Ontario, K1A 0Y3, Canada.
| | - Reid A Van Brabant
- Natural Resources Canada, Government of Canada, 930 Carling Ave (CEF, Bldg 7, Observatory Cr.), Ottawa, Ontario, K1A 0Y3, Canada.
| | - Bradley J A Harvey
- Natural Resources Canada, Government of Canada, 930 Carling Ave (CEF, Bldg 7, Observatory Cr.), Ottawa, Ontario, K1A 0Y3, Canada.
| | - Bernard F Phlips
- Space Science Division, U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
| | - Anthony L Hutcheson
- Space Science Division, U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
| | - Emily G Jackson
- Formerly: NRC Research Associate Resident at the U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
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11
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Wissmann F, Klages T. A simple method to monitor the dose rate of secondary cosmic radiation at altitude. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:71-84. [PMID: 30524002 DOI: 10.1088/1361-6498/aaeeae] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Monitoring the ambient dose equivalent rate at aviation altitudes is an ambitious task, which requires sophisticated dosemeter systems and the possibility to carry out such measurements on board aircraft. A rather simple approach has been investigated in this study: soundings with weather balloons up to an altitude of 30 km. This paper summarises the measurements carried out between 2011 and 2016. The results indicate that annual measurements of the ambient dose equivalent rate at altitudes of around 20 km are a reliable tool to monitor the variation of the dose rate in the atmosphere owing to the solar activity.
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Affiliation(s)
- F Wissmann
- Bundesamt für Strahlenschutz (BfS), Köpenicker Allee 120-130, D-10318, Berlin, Germany
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12
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Goldhagen P. An Extended-Range Multisphere Neutron Spectrometer with High Sensitivity and Improved Resolution. NUCL TECHNOL 2017. [DOI: 10.13182/nt11-a12274] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Paul Goldhagen
- U.S. Department of Homeland Security National Urban Security Technology Laboratory201 Varick Street, New York, New York 10014-7447
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13
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Howell RM, Burgett E, Hertel NE, Kry SF, Wang Z, Salehpour M. Measurement of High-Energy Neutron Spectra with a Bonner Sphere Extension System. NUCL TECHNOL 2017. [DOI: 10.13182/nt09-a9204] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Rebecca M. Howell
- The University of Texas M. D. Anderson Cancer Center Department of Radiation Physics, Unit 94, 1515 Holcombe, Houston, Texas 77030
| | - Eric Burgett
- Georgia Institute of Technology G. W. Woodruff School of Mechanical Engineering, Nuclear and Radiological Engineering Program 900 Atlantic Drive, Atlanta, Georgia 30322-0405
| | - Nolan E. Hertel
- Georgia Institute of Technology G. W. Woodruff School of Mechanical Engineering, Nuclear and Radiological Engineering Program 900 Atlantic Drive, Atlanta, Georgia 30322-0405
| | - Stephen F. Kry
- The University of Texas M. D. Anderson Cancer Center, Department of Radiation PhysicsUnit 94, 1515 Holcombe, Houston, Texas 77030
| | - Zhonglu Wang
- The University of Texas M. D. Anderson Cancer Center, Department of Radiation PhysicsUnit 94, 1515 Holcombe, Houston, Texas 77030
| | - Mohammad Salehpour
- The University of Texas M. D. Anderson Cancer Center, Department of Radiation PhysicsUnit 94, 1515 Holcombe, Houston, Texas 77030
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14
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Hanu AR, Barberiz J, Bonneville D, Byun SH, Chen L, Ciambella C, Dao E, Deshpande V, Garnett R, Hunter SD, Jhirad A, Johnston EM, Kordic M, Kurnell M, Lopera L, McFadden M, Melnichuk A, Nguyen J, Otto A, Scott R, Wagner DL, Wiendels M. NEUDOSE: A CubeSat Mission for Dosimetry of Charged Particles and Neutrons in Low-Earth Orbit. Radiat Res 2016; 187:42-49. [PMID: 28001909 DOI: 10.1667/rr14491.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
During space missions, astronauts are exposed to a stream of energetic and highly ionizing radiation particles that can suppress immune system function, increase cancer risks and even induce acute radiation syndrome if the exposure is large enough. As human exploration goals shift from missions in low-Earth orbit (LEO) to long-duration interplanetary missions, radiation protection remains one of the key technological issues that must be resolved. In this work, we introduce the NEUtron DOSimetry & Exploration (NEUDOSE) CubeSat mission, which will provide new measurements of dose and space radiation quality factors to improve the accuracy of cancer risk projections for current and future space missions. The primary objective of the NEUDOSE CubeSat is to map the in situ lineal energy spectra produced by charged particles and neutrons in LEO where most of the preparatory activities for future interplanetary missions are currently taking place. To perform these measurements, the NEUDOSE CubeSat is equipped with the Charged & Neutral Particle Tissue Equivalent Proportional Counter (CNP-TEPC), an advanced radiation monitoring instrument that uses active coincidence techniques to separate the interactions of charged particles and neutrons in real time. The NEUDOSE CubeSat, currently under development at McMaster University, provides a modern approach to test the CNP-TEPC instrument directly in the unique environment of outer space while simultaneously collecting new georeferenced lineal energy spectra of the radiation environment in LEO.
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Affiliation(s)
- A R Hanu
- a NASA Goddard Space Flight Center, Greenbelt, Maryland 20771
| | - J Barberiz
- Department of bElectrical and Computer Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - D Bonneville
- c Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - S H Byun
- d Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - L Chen
- c Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - C Ciambella
- f Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - E Dao
- d Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - V Deshpande
- e Department of Mechanical Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - R Garnett
- d Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - S D Hunter
- a NASA Goddard Space Flight Center, Greenbelt, Maryland 20771
| | - A Jhirad
- Department of bElectrical and Computer Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - E M Johnston
- d Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - M Kordic
- Department of bElectrical and Computer Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - M Kurnell
- c Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - L Lopera
- f Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - M McFadden
- d Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - A Melnichuk
- Department of bElectrical and Computer Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - J Nguyen
- Department of bElectrical and Computer Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - A Otto
- e Department of Mechanical Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - R Scott
- e Department of Mechanical Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - D L Wagner
- c Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - M Wiendels
- Department of bElectrical and Computer Engineering, McMaster University, Hamilton, Ontario L8S 4K1, Canada
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15
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Mishev AL. Contribution of cosmic ray particles to radiation environment at high mountain altitude: Comparison of Monte Carlo simulations with experimental data. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 153:15-22. [PMID: 26714058 DOI: 10.1016/j.jenvrad.2015.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 12/01/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
A numerical model for assessment of the effective dose due to secondary cosmic ray particles of galactic origin at high mountain altitude of about 3000 m above the sea level is presented. The model is based on a newly numerically computed effective dose yield function considering realistic propagation of cosmic rays in the Earth magnetosphere and atmosphere. The yield function is computed using a full Monte Carlo simulation of the atmospheric cascade induced by primary protons and α- particles and subsequent conversion of secondary particle fluence (neutrons, protons, gammas, electrons, positrons, muons and charged pions) to effective dose. A lookup table of the newly computed effective dose yield function is provided. The model is compared with several measurements. The comparison of model simulations with measured spectral energy distributions of secondary cosmic ray neutrons at high mountain altitude shows good consistency. Results from measurements of radiation environment at high mountain station--Basic Environmental Observatory Moussala (42.11 N, 23.35 E, 2925 m a.s.l.) are also shown, specifically the contribution of secondary cosmic ray neutrons. A good agreement with the model is demonstrated.
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Affiliation(s)
- A L Mishev
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia, Bulgaria; ReSolve Center of Excellence, University of Oulu, Finland.
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16
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Smith MB, Khulapko S, Andrews HR, Arkhangelsky V, Ing H, Koslowksy MR, Lewis BJ, Machrafi R, Nikolaev I, Shurshakov V. Bubble-detector measurements of neutron radiation in the international space station: ISS-34 to ISS-37. RADIATION PROTECTION DOSIMETRY 2016; 168:154-166. [PMID: 25899609 PMCID: PMC4884878 DOI: 10.1093/rpd/ncv181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 03/02/2015] [Accepted: 03/06/2015] [Indexed: 06/04/2023]
Abstract
Bubble detectors have been used to characterise the neutron dose and energy spectrum in several modules of the International Space Station (ISS) as part of an ongoing radiation survey. A series of experiments was performed during the ISS-34, ISS-35, ISS-36 and ISS-37 missions between December 2012 and October 2013. The Radi-N2 experiment, a repeat of the 2009 Radi-N investigation, included measurements in four modules of the US orbital segment: Columbus, the Japanese experiment module, the US laboratory and Node 2. The Radi-N2 dose and spectral measurements are not significantly different from the Radi-N results collected in the same ISS locations, despite the large difference in solar activity between 2009 and 2013. Parallel experiments using a second set of detectors in the Russian segment of the ISS included the first characterisation of the neutron spectrum inside the tissue-equivalent Matroshka-R phantom. These data suggest that the dose inside the phantom is ∼70% of the dose at its surface, while the spectrum inside the phantom contains a larger fraction of high-energy neutrons than the spectrum outside the phantom. The phantom results are supported by Monte Carlo simulations that provide good agreement with the empirical data.
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Affiliation(s)
- M B Smith
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - S Khulapko
- Institute for Biomedical Problems, Russian Academy of Sciences, 76A Khoroshevskoe sh., Moscow 123007, Russia RSC-Energia, 4A Lenin str., Korolev, Moscow Region 141070, Russia
| | - H R Andrews
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - V Arkhangelsky
- Institute for Biomedical Problems, Russian Academy of Sciences, 76A Khoroshevskoe sh., Moscow 123007, Russia
| | - H Ing
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - M R Koslowksy
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - B J Lewis
- Faculty of Energy Systems and Nuclear Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, ON, Canada L1H 7K4
| | - R Machrafi
- Faculty of Energy Systems and Nuclear Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, ON, Canada L1H 7K4
| | - I Nikolaev
- RSC-Energia, 4A Lenin str., Korolev, Moscow Region 141070, Russia
| | - V Shurshakov
- Institute for Biomedical Problems, Russian Academy of Sciences, 76A Khoroshevskoe sh., Moscow 123007, Russia
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Langford T, Beise E, Breuer H, Heimbach C, Ji G, Nico J. Development and Characterization of a High Sensitivity Segmented Fast Neutron Spectrometer (FaNS-2). JOURNAL OF INSTRUMENTATION : AN IOP AND SISSA JOURNAL 2016; 11:P01006. [PMID: 27226807 PMCID: PMC4873776 DOI: 10.1088/1748-0221/11/01/p01006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present the development of a segmented fast neutron spectrometer (FaNS-2) based upon plastic scintillator and 3He proportional counters. It was designed to measure both the flux and spectrum of fast neutrons in the energy range of few MeV to 1 GeV. FaNS-2 utilizes capture-gated spectroscopy to identify neutron events and reject backgrounds. Neutrons deposit energy in the plastic scintillator before capturing on a 3He nucleus in the proportional counters. Segmentation improves neutron energy reconstruction while the large volume of scintillator increases sensitivity to low neutron fluxes. A main goal of its design is to study comparatively low neutron fluxes, such as cosmogenic neutrons at the Earth's surface, in an underground environment, or from low-activity neutron sources. In this paper, we present details of its design and construction as well as its characterization with a calibrated 252Cf source and monoenergetic neutron fields of 2.5 MeV and 14 MeV. Detected monoenergetic neutron spectra are unfolded using a Singular Value Decomposition method, demonstrating a 5% energy resolution at 14 MeV. Finally, we discuss plans for measuring the surface and underground cosmogenic neutron spectra with FaNS-2.
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Affiliation(s)
- T.J. Langford
- Wright Laboratory, Yale University, New Haven, CT 06511 USA
| | - E.J. Beise
- Department of Physics, University of Maryland, College Park, MD 20742 USA
| | - H. Breuer
- Department of Physics, University of Maryland, College Park, MD 20742 USA
| | - C.R. Heimbach
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 USA
| | - G. Ji
- Department of Physics, University of Maryland, College Park, MD 20742 USA
| | - J.S. Nico
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 USA
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18
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Hubert G, Cheminet A. Radiation Effects Investigations Based on Atmospheric Radiation Model (ATMORAD) Considering GEANT4 Simulations of Extensive Air Showers and Solar Modulation Potential. Radiat Res 2015; 184:83-94. [DOI: 10.1667/rr14028.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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19
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Smith MB, Khulapko S, Andrews HR, Arkhangelsky V, Ing H, Lewis BJ, Machrafi R, Nikolaev I, Shurshakov V. Bubble-detector measurements in the Russian segment of the International Space Station during 2009-12. RADIATION PROTECTION DOSIMETRY 2015; 163:1-13. [PMID: 24714114 DOI: 10.1093/rpd/ncu053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Measurements using bubble detectors have been performed in order to characterise the neutron dose and energy spectrum in the Russian segment of the International Space Station (ISS). Experiments using bubble dosemeters and a bubble-detector spectrometer, a set of six detectors with different energy thresholds that is used to determine the neutron spectrum, were performed during the ISS-22 (2009) to ISS-33 (2012) missions. The spectrometric measurements are in good agreement with earlier data, exhibiting expected features of the neutron energy spectrum in space. Experiments using a hydrogenous radiation shield show that the neutron dose can be reduced by shielding, with a reduction similar to that determined in earlier measurements using bubble detectors. The bubble-detector data are compared with measurements performed on the ISS using other instruments and are correlated with potential influencing factors such as the ISS altitude and the solar activity. Surprisingly, these influences do not seem to have a strong effect on the neutron dose or energy spectrum inside the ISS.
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Affiliation(s)
- M B Smith
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - S Khulapko
- State Scientific Centre, Institute for Biomedical Problems, Russian Academy of Sciences, 76A Khoroshevskoe Sh., 123007 Moscow, Russia RSC-Energia, 4A Lenin Str., 141070 Korolev, Moscow Region, Russia
| | - H R Andrews
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - V Arkhangelsky
- State Scientific Centre, Institute for Biomedical Problems, Russian Academy of Sciences, 76A Khoroshevskoe Sh., 123007 Moscow, Russia
| | - H Ing
- Bubble Technology Industries, PO Box 100, Chalk River, ON, Canada K0J 1J0
| | - B J Lewis
- Faculty of Energy Systems and Nuclear Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, ON, Canada L1H 7K4
| | - R Machrafi
- Faculty of Energy Systems and Nuclear Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, ON, Canada L1H 7K4
| | - I Nikolaev
- RSC-Energia, 4A Lenin Str., 141070 Korolev, Moscow Region, Russia
| | - V Shurshakov
- State Scientific Centre, Institute for Biomedical Problems, Russian Academy of Sciences, 76A Khoroshevskoe Sh., 123007 Moscow, Russia
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20
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Rühm W, Mares V, Pioch C, Agosteo S, Endo A, Ferrarini M, Rakhno I, Rollet S, Satoh D, Vincke H. Comparison of Bonner sphere responses calculated by different Monte Carlo codes at energies between 1 MeV and 1 GeV – Potential impact on neutron dosimetry at energies higher than 20 MeV. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2014.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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21
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Zhu Q, Song F, Ren J, Chen X, Zhou B. The criteria for selecting a method for unfolding neutron spectra based on the information entropy theory. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2013.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Chen H, Rogalski MM, Anker JN. Advances in functional X-ray imaging techniques and contrast agents. Phys Chem Chem Phys 2012; 14:13469-86. [PMID: 22962667 PMCID: PMC3569739 DOI: 10.1039/c2cp41858d] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
X-rays have been used for non-invasive high-resolution imaging of thick biological specimens since their discovery in 1895. They are widely used for structural imaging of bone, metal implants, and cavities in soft tissue. Recently, a number of new contrast methodologies have emerged which are expanding X-ray's biomedical applications to functional as well as structural imaging. These techniques are promising to dramatically improve our ability to study in situ biochemistry and disease pathology. In this review, we discuss how X-ray absorption, X-ray fluorescence, and X-ray excited optical luminescence can be used for physiological, elemental, and molecular imaging of vasculature, tumors, pharmaceutical distribution, and the surface of implants. Imaging of endogenous elements, exogenous labels, and analytes detected with optical indicators will be discussed.
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Affiliation(s)
- Hongyu Chen
- Department of Chemistry, Center for Optical Materials Science and Engineering Technology (COMSET), Clemson University, Clemson, SC 29634, USA
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23
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Smith MB, Akatov Y, Andrews HR, Arkhangelsky V, Chernykh IV, Ing H, Khoshooniy N, Lewis BJ, Machrafi R, Nikolaev I, Romanenko RY, Shurshakov V, Thirsk RB, Tomi L. Measurements of the neutron dose and energy spectrum on the International Space Station during expeditions ISS-16 to ISS-21. RADIATION PROTECTION DOSIMETRY 2012; 153:509-533. [PMID: 22826353 DOI: 10.1093/rpd/ncs129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
As part of the international Matroshka-R and Radi-N experiments, bubble detectors have been used on board the ISS in order to characterise the neutron dose and the energy spectrum of neutrons. Experiments using bubble dosemeters inside a tissue-equivalent phantom were performed during the ISS-16, ISS-18 and ISS-19 expeditions. During the ISS-20 and ISS-21 missions, the bubble dosemeters were supplemented by a bubble-detector spectrometer, a set of six detectors that was used to determine the neutron energy spectrum at various locations inside the ISS. The temperature-compensated spectrometer set used is the first to be developed specifically for space applications and its development is described in this paper. Results of the dose measurements indicate that the dose received at two different depths inside the phantom is not significantly different, suggesting that bubble detectors worn by a person provide an accurate reading of the dose received inside the body. The energy spectra measured using the spectrometer are in good agreement with previous measurements and do not show a strong dependence on the precise location inside the station. To aid the understanding of the bubble-detector response to charged particles in the space environment, calculations have been performed using a Monte-Carlo code, together with data collected on the ISS. These calculations indicate that charged particles contribute <2% to the bubble count on the ISS, and can therefore be considered as negligible for bubble-detector measurements in space.
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Affiliation(s)
- M B Smith
- Bubble Technology Industries, Chalk River, ON, Canada.
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24
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Poje M, Vuković B, Radolić V, Miklavčić I, Faj D, Varga Pajtler M, Planinić J. Mapping of cosmic radiation dose in Croatia. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2012; 103:30-33. [PMID: 22036155 DOI: 10.1016/j.jenvrad.2011.08.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 07/01/2011] [Accepted: 08/26/2011] [Indexed: 05/31/2023]
Abstract
The Earth is continually bombarded by high-energy particles coming from the outer space and the sun. These particles, termed cosmic radiation, interact with nuclei of atmospheric constituents and decrease in intensity with depth in the atmosphere. Measurements of photon and gamma radiation, performed with a Radiameter at 1 m above the ground, indicated dose rates of 50-100 nSv/h. The neutron dose rate was measured with the CR-39 track etch detector calibrated by the CERN-EU high-energy Reference Field (CERF) facility. Correlation between neutron dose rates and altitudes at 36 sites was examined in order to obtain a significant positive correlation coefficient; the resulting linear regression enabled estimation of a neutron dose at particular altitude. The measured neutron dose rate in Osijek (altitude of 89 m, latitude of 45.31° N) was 110 nSv/h.
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Affiliation(s)
- M Poje
- Department of Physics, University of Osijek, P.O. Box 125, Gajev trg 6, 31000 Osijek, Croatia
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25
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Measurement of cosmic-ray origin neutrons using a scintillation detector at the summit of Mt. Fuji. RADIAT MEAS 2011. [DOI: 10.1016/j.radmeas.2011.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Riedmann RA, Purtschert R. Natural ³⁷Ar concentrations in soil air: implications for monitoring underground nuclear explosions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:8656-8664. [PMID: 21877757 DOI: 10.1021/es201192u] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
For on-site inspections (OSI) under the Comprehensive Nuclear-Test-Ban Treaty (CTBT) measurement of the noble gas ³⁷Ar is considered an important technique. ³⁷Ar is produced underground by neutron activation of Calcium by the reaction ⁴⁰Ca(n,α)³⁷Ar. The naturally occurring equilibrium ³⁷Ar concentration balance in soil air is a function of an exponentially decreasing production rate from cosmic ray neutrons with increasing soil depth, diffusive transport in the soil air, and radioactive decay (T(1/2): 35 days). In this paper for the first time, measurements of natural ³⁷Ar activities in soil air are presented. The highest activities of ~100 mBq m⁻³ air are 2 orders of magnitude larger than in the atmosphere and are found in 1.5-2.5 m depth. At depths > 8 m ³⁷Ar activities are < 20 mBq m⁻³ air. After identifying the main ³⁷Ar production and gas transport factors the expected global activity range distribution of ³⁷Ar in shallow subsoil (0.7 m below the surface) was estimated. In high altitude soils, with large amounts of Calcium and with low gas permeability, ³⁷Ar activities may reach values up to 1 Bq m⁻³.
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Affiliation(s)
- Robin A Riedmann
- Climate- & Environmental Physics, Physics Institute, University of Berne, Switzerland, CH-3012 Berne, Switzerland.
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27
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Federico C, Gonçalez O, Fonseca E, Martin I, Caldas L. Neutron spectra measurements in the south Atlantic anomaly region. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.06.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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28
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30
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Takada M, Yajima K, Yasuda H, Sato T, Nakamura T. Neutron, photon and proton energy spectra at high altitude measured using a phoswich-type neutron detector. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.06.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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31
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Caruso AN. The physics of solid-state neutron detector materials and geometries. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:443201. [PMID: 21403341 DOI: 10.1088/0953-8984/22/44/443201] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Detection of neutrons, at high total efficiency, with greater resolution in kinetic energy, time and/or real-space position, is fundamental to the advance of subfields within nuclear medicine, high-energy physics, non-proliferation of special nuclear materials, astrophysics, structural biology and chemistry, magnetism and nuclear energy. Clever indirect-conversion geometries, interaction/transport calculations and modern processing methods for silicon and gallium arsenide allow for the realization of moderate- to high-efficiency neutron detectors as a result of low defect concentrations, tuned reaction product ranges, enhanced effective omnidirectional cross sections and reduced electron-hole pair recombination from more physically abrupt and electronically engineered interfaces. Conversely, semiconductors with high neutron cross sections and unique transduction mechanisms capable of achieving very high total efficiency are gaining greater recognition despite the relative immaturity of their growth, lithographic processing and electronic structure understanding. This review focuses on advances and challenges in charged-particle-based device geometries, materials and associated mechanisms for direct and indirect transduction of thermal to fast neutrons within the context of application. Calorimetry- and radioluminescence-based intermediate processes in the solid state are not included.
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Affiliation(s)
- A N Caruso
- Department of Physics, University of Missouri-Kansas City, Kansas City, MO 64110, USA.
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32
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TAKADA M, YAJIMA K, YASUDA H, SATO T, NAKAMURA T. Measurement of Atmospheric Neutron and Photon Energy Spectra at Aviation Altitudes using a Phoswich-Type Neutron Detector. J NUCL SCI TECHNOL 2010. [DOI: 10.1080/18811248.2010.9720972] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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33
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Vuković B, Poje M, Varga M, Radolić V, Miklavcić I, Faj D, Stanić D, Planinić J. Measurements of neutron radiation in aircraft. Appl Radiat Isot 2010; 68:2398-402. [PMID: 20620072 DOI: 10.1016/j.apradiso.2010.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Revised: 06/14/2010] [Accepted: 06/17/2010] [Indexed: 10/19/2022]
Abstract
Radiation environment is a complex mixture of charged particles of the solar and galactic origin, as well as of secondary particles created in an interaction of galactic cosmic particles with the nuclei of the Earth's atmosphere. A radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. In order to measure a neutron component of the cosmic radiation, we investigated a few combinations of a track etch detector (CR-39, LR-115) with a plastic converter or boron foil. Detector calibration was performed on neutrons coming from the nuclear reactor, as well as in the CERN-EU high-energy Reference Field (CERF) facility. From November 2007 to September 2008, the neutron dose equivalent was measured by the track detectors during five aircraft flights, in the north geographical latitude from 21° to 58°; the respective average dose rate, determined by using the D-4 detector (CR-39/B), was Ḣ(n)=5.9 μSv/h. The photon dose rate, measured by the electronic dosimeter RAD-60 SE, had the average value of Ḣ(f)=1.4 μSv/h.
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Affiliation(s)
- B Vuković
- Department of Physics, University of Osijek, Osijek, P.O. Box 125, Croatia
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34
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YAJIMA K, YASUDA H, TAKADA M, SATO T, GOKA T, MATSUMOTO H, NAKAMURA T. Measurements of Cosmic-Ray Neutron Energy Spectra from Thermal to 15 MeV with Bonner Ball Neutron Detector in Aircraft. J NUCL SCI TECHNOL 2010. [DOI: 10.1080/18811248.2010.9711934] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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35
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Nagaoka K, Hiraide I, Sato K, Nakamura T. Nationwide measurements of cosmic-ray dose rates throughout Japan. RADIATION PROTECTION DOSIMETRY 2009; 132:365-374. [PMID: 19151128 DOI: 10.1093/rpd/ncn316] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Cosmic-ray dose rates on the ground were measured throughout Japan. Neutron dose rates were measured as ambient dose equivalent rates (H*(10)) at 240 points using high-sensitivity neutron REM counters. In addition, cosmic rays directly ionising plus photon components were measured with an ionisation chamber. Time variation due to solar modulation during this study was corrected based on the results of sequential measurements. The effects of altitude, geomagnetic latitude, rainfall and snowfall on the neutron dose rate were inferred from the measured results. The mean value of the neutron dose rates (H*(10)) measured at 47 points of prefectural capitals in Japan was 4.0 nSv h(-1). The value corrected for the energy response of the REM counter was 6.4 nSv h(-1), corresponding to 4.8 nSv h(-1) as an effective dose (ISO). The mean value of the cosmic ray directly ionising plus photon components as an effective dose was 31 nSv h(-1).
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Affiliation(s)
- K Nagaoka
- Japan Chemical Analysis Center (JCAC), 295-3 Sanno-cho, Inage-ku, Chiba-shi, Chiba 263-0002, Japan.
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36
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Monk SD, Joyce MJ, Jarrah Z, King D, Oppenheim M. A portable energy-sensitive cosmic neutron detection instrument. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:023301. [PMID: 18315287 DOI: 10.1063/1.2835717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The construction and testing of a portable energy-sensitive neutron instrument are described. This instrument has been designed and constructed for the primary purpose of characterizing cosmic-ray neutron fields in the upper atmosphere and in cosmic reference field facilities. The instrument comprises a helium-3 proportional counter surrounded by 15 mm of lead and 140 mm of polyethylene creating a spherical structure with a diameter of 34 cm. The instrument also incorporates 12 boron-coated diodes, six on the outside of the polyethylene layer with six placed within the structure. The dimensions, materials, and arrangement of these in the instrument have previously been optimized with the MCNPX Monte Carlo simulation software to provide a compromise between the requirements of portability and spectral response. Testing took place at several locations and experimental data from the instrument's operation at the high-altitude Jungfraujoch laboratory in the Swiss alps are presented.
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Affiliation(s)
- S D Monk
- Department of Engineering, Lancaster University, Lancaster LA1 4YR, United Kingdom
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37
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Endo S, Shizuma K, Tanaka K, Ishikawa M, Rühm W, Egbert SD, Hoshi M. Radioactivity in atomic-bomb samples from exposure to environmental neutrons. HEALTH PHYSICS 2007; 93:689-695. [PMID: 17993849 DOI: 10.1097/01.hp.0000278420.51860.2d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
For about one decade, activation measurements performed on environmental samples from a distance larger than 1 km from the hypocenter of the atomic-bomb explosion over Hiroshima suggested much higher thermal neutron fluences to the survivors than predicted. This caused concern among the radiation protection community and prompted a complete re-evaluation of all aspects of survivor dosimetry. While it was shown recently that secondary neutrons from cosmic radiation and other sources have probably been the reason for the high measured concentrations of the long-lived radioisotope 36Cl in these samples, the source for high measured concentrations of the short-lived radionuclides 152Eu and 60Co has not yet been investigated in detail. In order to quantify the production of 152Eu and 60Co in environmental samples by secondary neutrons from cosmic radiation, thermal neutron fluxes were measured by means of a He gas proportional counter in various buildings where these samples had been and still are being stored. Because a 252Cf neutron source has been operated occasionally close to one of the sample storage rooms, additional neutron flux measurements were carried out when the neutron source was in operation. The thermal neutron fluxes measured ranged from 0.00017 to 0.00093 n cm(-2) s(-1) and depended on the floor number of the investigated building. Based on the measured neutron fluxes, the specific activities from the reactions 151Eu(n,gamma)152Eu and 59Co(n,gamma)60Co in the atomic-bomb samples were estimated to be 7.9 mBq g(-1) Eu and 0.27 mBq g(-1) Co, respectively, in saturation. These activities are much lower than those recently measured in samples that had been exposed to atomic-bomb neutrons. It is therefore concluded that environmental and moderated 252Cf neutrons are not the source for the high activities that had been measured in these samples.
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Affiliation(s)
- S Endo
- Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.
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38
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Vuković B, Radolić V, Lisjak I, Vekić B, Poje M, Planinić J. Some cosmic radiation dose measurements aboard flights connecting Zagreb Airport. Appl Radiat Isot 2007; 66:247-51. [PMID: 17935999 DOI: 10.1016/j.apradiso.2007.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 08/07/2007] [Accepted: 09/03/2007] [Indexed: 10/22/2022]
Abstract
When primary particles from space, mainly protons, enter the atmosphere, they produce interactions with air nuclei, and cosmic-ray showers are induced. The radiation field at aircraft altitude is complex, with different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard A320 and ATR40 aircraft was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter; the neutron dose was measured with the neutron dosimeter consisted of LR-115 track detector and boron foil BN-1 or 10B converter. The estimated occupational effective dose for the aircraft crew (A320) working 500 h per year was 1.64 mSv. Another experiment was performed at the flights Zagreb-Paris-Buenos Aires and reversely, when one measured non-neutron cosmic radiation dose; for 26.7 h of flight, the MINI 6100 dosimeter gave an average dose rate of 2.3 microSv/h and the TLD dosimeter registered the dose equivalent of 75 microSv or the average dose rate of 2.7 microSv/h; the neutron dosimeter gave the dose rate of 2.4 microSv/h. In the same month, February 2005, a traveling to Japan (24-h-flight: Zagreb-Frankfurt-Tokyo and reversely) and the TLD-100 measurement showed the average dose rate of 2.4microSv/h; the neutron dosimeter gave the dose rate of 2.5 microSv/h. Comparing dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level, we could conclude that the neutron component carried about 50% of the total dose, that was near other known data.
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Affiliation(s)
- B Vuković
- Department of Physics, University of Osijek, Osijek, P.O. Box 125, Croatia
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39
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Zaichkina SI, Rozanova OM, Aptikaeva GF, Akhmadieva AK, Smirnova EN, Romanchenko SP, Sirota NP, Vachrusheva OA, Peleshko VN. Peculiarities of the effect of low-dose-rate radiation simulating high-altitude flight conditions on mice in vivo. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2007; 46:131-5. [PMID: 17415582 DOI: 10.1007/s00411-007-0107-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2006] [Accepted: 03/12/2007] [Indexed: 05/14/2023]
Abstract
In the present work, the effect of a low-dose rate of high-LET radiation in polychromatic erythrocytes of mice bone marrow was investigated in vivo. The spectral and component composition of the radiation field used was similar to that present in the atmosphere at an altitude of about 10 km. The dose dependence, adaptive response, and genetic instability in the F1 generation born from males irradiated under these conditions were examined using the micronucleus test. Irradiation of the mice was performed for 24 h per day in the radiation field behind the concrete shield of the Serpukhov accelerator. Protons of 70 GeV were used over a period of 15-31 days, to accumulate doses of 11.5-31.5 cGy. The experiment demonstrated that irradiation of mice in vivo in this dose range leads to an increase in cytogenetic damage to bone marrow cells, but does not induce any adaptive response. In mice pre-irradiated with a dose of 11.5 cGy, an increase in sensitivity was observed after an additional irradiation with a dose of 1.5 Gy. The absence of an adaptive response suggests existence of genetic instability.
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Affiliation(s)
- S I Zaichkina
- Institute of Theoretical and Experimental Biophysics, Pushchino, Russia.
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40
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KOWATARI M, OHTA Y, SATOH S, NAGAOKA K, ABUKAWA J, NAKAMURA T. Evaluation of Geomagnetic Latitude Dependence of the Cosmic-ray Induced Environmental Neutrons in Japan. J NUCL SCI TECHNOL 2007. [DOI: 10.1080/18811248.2007.9711264] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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41
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Monk SD, Joyce MJ. The design of a portable cosmic ray three-band neutron detector. RADIATION PROTECTION DOSIMETRY 2007; 123:3-14. [PMID: 16829509 DOI: 10.1093/rpd/ncl074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The design of a portable three-band cosmic-ray neutron detector is reported in this article. This instrument has been designed to characterise cosmic ray neutron fields in the upper atmosphere and in cosmic reference field facilities. The design utilises a spherical moderator with a layer of spallation material covering a central (3)He proportional counter. The instrument incorporates twelve lithium-coated diodes, six on the outside of the polyethylene layer and six placed within the structure. The dimensions, materials and arrangement of these in the instrument have been optimised with MCNPX to provide a compromise between the requirements of portability and spectral response.
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Affiliation(s)
- S D Monk
- Nuclear and Biomedical Engineering Research Group, Department of Engineering, Lancaster University, Lancaster LA1 4YR, UK
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Vuković B, Radolić V, Miklavcić I, Poje M, Varga M, Planinić J. Cosmic radiation dose in aircraft--a neutron track etch detector. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2007; 98:264-73. [PMID: 17600597 DOI: 10.1016/j.jenvrad.2007.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 04/26/2007] [Accepted: 05/14/2007] [Indexed: 05/16/2023]
Abstract
Cosmic radiation bombards us at high altitude by ionizing particles. The radiation environment is a complex mixture of charged particles of solar and galactic origin, as well as of secondary particles produced in interaction of the galactic cosmic particles with the nuclei of atmosphere of the Earth. The radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard ATR 42 and A 320 aircrafts (flight level of 8 and 11 km, respectively) was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter. The estimated occupational effective dose for the aircraft crew (A 320) working 500 h per year was 1.64 mSv. Other experiments, or dose rate measurements with the neutron dosimeter, consisting of LR-115 track detector and boron foil BN-1 or 10B converter, were performed on five intercontinental flights. Comparison of the dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level showed that the neutron component carried about 50% of the total dose. The dose rate measurements on the flights from the Middle Europe to the South and Middle America, then to Korea and Japan, showed that the flights over or near the equator region carried less dose rate; this was in accordance with the known geomagnetic latitude effect.
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Affiliation(s)
- B Vuković
- Department of Physics, University of Osijek, 31000 Osijek, P.O. Box 125, Gajev trg 6, Croatia
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NAKAMURA T, NUNOMIYA T, ABE S, TERUNUMA K, SUZUKI H. Sequential Measurements of Cosmic-Ray Neutron Spectrum and Dose Rate at Sea Level in Sendai, Japan. J NUCL SCI TECHNOL 2005. [DOI: 10.1080/18811248.2005.9711035] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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44
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KOWATARI M, NAGAOKA K, SATOH S, OHTA Y, ABUKAWA J, TACHIMORI S, NAKAMURA T. Evaluation of the Altitude Variation of the Cosmic-ray Induced Environmental Neutrons in the Mt. Fuji Area. J NUCL SCI TECHNOL 2005. [DOI: 10.1080/18811248.2004.9726416] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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45
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Nakamura T, Nunomiya T, Sasaki M. Development of active environmental and personal neutron dosemeters. RADIATION PROTECTION DOSIMETRY 2004; 110:169-181. [PMID: 15353641 DOI: 10.1093/rpd/nch158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
For neutron dosimetry in the radiation environment surrounding nuclear facilities, two types of environmental neutron dosemeters, the high-sensitivity rem counter and the high-sensitivity multi-moderator, the so-called Bonner ball, have been developed and the former is commercially available from Fuji Electric Co. By using these detectors, the cosmic ray neutrons at sea level have been sequentially measured for about 3 y to investigate the time variation of neutron spectrum and ambient dose equivalent influenced by cosmic and terrestrial effects. Our Bonner ball has also been selected as the neutron detector in the International Space Station and has already been used to measure neutrons in the US experimental module. The real time wide-range personal neutron dosemeter which uses two silicon semiconductor detectors has been developed for personal dosimetry and is commercially available from Fuji Electric Co. This dosemeter has good characteristics, fitted to the fluence-to-dose conversion factor in the energy range from thermal energies to several tens of mega-electron-volts and is now widely used in various nuclear facilities.
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Affiliation(s)
- T Nakamura
- Cyclotron and Radioisotope Center, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai, Japan.
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46
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Clem JM, De Angelis G, Goldhagen P, Wilson JW. New calculations of the atmospheric cosmic radiation field--results for neutron spectra. RADIATION PROTECTION DOSIMETRY 2004; 110:423-428. [PMID: 15353685 DOI: 10.1093/rpd/nch175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The propagation of primary cosmic rays through the Earth's atmosphere and the energy spectra of the resulting secondary particles have been calculated using the Monte Carlo transport code FLUKA with several novel auxiliary methods. Solar-modulated primary cosmic ray spectra were determined through an analysis of simultaneous proton and helium measurements made on spacecraft or high-altitude balloon flights. Primary protons and helium ions are generated within the rigidity range of 0.5 GV-20 TV, uniform in cos2theta. For a given location, primaries above the effective angle-dependent geomagnetic cut-off rigidity, and re-entrant albedo protons, are transported through the atmosphere. Helium ions are initially transported using a separate transport code called HEAVY to simulate fragmentation. HEAVY interfaces with FLUKA to provide interaction starting points for each nucleon originating from a helium nucleus. Calculated cosmic ray neutron spectra and consequent dosimetric quantities for locations with a wide range of altitude (atmospheric depth) and geomagnetic cut-off are presented and compared with measurements made on a high-altitude aeroplane. Helium ion propagation using HEAVY and inclusion of re-entrant albedo protons with the incident primary spectra significantly improved the agreement of the calculated cosmic ray neutron spectra with measured spectra. These cosmic ray propagation calculations provide the basis for a new atmospheric ionising radiation (AIR) model for air-crew dosimetry, calculation of effects on microelectronics, production of cosmogenic radionuclides and other uses.
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Affiliation(s)
- J M Clem
- Bartol Research Institute, University of Delaware, Newark, DE 19716, USA.
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47
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Hajek M, Berger T, Vana N. Passive in-flight neutron spectrometry by means of bonner spheres. RADIATION PROTECTION DOSIMETRY 2004; 110:343-346. [PMID: 15353671 DOI: 10.1093/rpd/nch183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The spectral distribution of the neutron fluence rate was determined on-board a series of eight trans-atlantic flights between Cologne (Germany) and Washington, DC (USA), using a passive Bonner Sphere spectrometer based on thermoluminescence detectors. Contrary to the commonly applied active systems, the passive instrument facilitates a complete discrimination of gamma ray and charged particle-induced events in the detector count rate. The system was calibrated in the CERN-EU High-Energy Reference Field (CERF). The measured spectra are compared with FLUKA Monte Carlo simulations and show excellent agreement.
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Affiliation(s)
- M Hajek
- Atomic Institute of the Austrian Universities, Stadionallee 2, A-1020 Vienna, Austria.
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Goldhagen P, Clem JM, Wilson JW. The energy spectrum of cosmic-ray induced neutrons measured on an airplane over a wide range of altitude and latitude. RADIATION PROTECTION DOSIMETRY 2004; 110:387-392. [PMID: 15353679 DOI: 10.1093/rpd/nch216] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Crews of high-altitude aircraft are exposed to radiation from galactic cosmic rays (GCRs). To help determine such exposures, the Atmospheric Ionizing Radiation Project, an international collaboration of 15 laboratories, made simultaneous radiation measurements with 14 instruments on a NASA ER-2 high-altitude airplane. The primary instrument was a sensitive extended-energy multisphere neutron spectrometer. Its detector responses were calculated for energies up to 100 GeV using the radiation transport code MCNPX 2.5.d with improved nuclear models and including the effects of the airplane structure. New calculations of GCR-induced particle spectra in the atmosphere were used to correct for spectrometer counts produced by protons, pions and light nuclear ions. Neutron spectra were unfolded from the corrected measured count rates using the deconvolution code MAXED 3.1. The results for the measured cosmic-ray neutron spectrum (thermal to >10 GeV), total neutron fluence rate, and neutron dose equivalent and effective dose rates, and their dependence on altitude and geomagnetic cut-off agree well with results from recent calculations of GCR-induced neutron spectra.
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Affiliation(s)
- P Goldhagen
- Environmental Measurements Laboratory, US Department of Homeland Security, New York, NY 10014, USA.
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50
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Goldhagen P, Clem JM, Wilson JW. Recent results form measurements of the energy spectrum of cosmic-ray induced neutrons aboard an ER-2 airplane and on the ground. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2003; 32:35-40. [PMID: 14727660 DOI: 10.1016/s0273-1177(03)90367-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Crews of future high-altitude commercial aircraft may be significantly exposed to atmospheric cosmic radiation from galactic cosmic rays (GCR). To help determine such exposures, the Atmospheric Ionizing Radiation Project, an international collaboration of 15 laboratories, made simultaneous radiation measurements with 14 instruments on a NASA ER-2 high-altitude aircraft. The primary instrument was a sensitive extended-energy multisphere neutron spectrometer, which was also used to make measurements on the ground. Its detector responses were calculated for neutrons and charged hadrons at energies up to 100 GeV using the radiation transport code MCNPX. We have now recalculated the detector responses including the effects of the airplane structure. We are also using new FLUKA calculations of GCR-induced hadron spectra in the atmosphere to correct for spectrometer counts produced by charged hadrons. Neutron spectra are unfolded from the corrected measured count rates using the MAXED code. Results for the measured cosmic-ray neutron spectrum (thermal to >10 GeV), total neutron fluence rate, and neutron dose equivalent and effective dose rates, and their dependence on altitude and geomagnetic cutoff generally agree well with results from recent calculations of GCR-induced neutron spectra.
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Affiliation(s)
- P Goldhagen
- Environmental Measurements Laboratory, U.S. Department of Homeland Security, New York, NY 10014, USA.
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