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Sample records for centaur radiation measurements

  1. First ultraviolet reflectance measurements of several Kuiper Belt objects, Kuiper Belt object satellites, and new ultraviolet measurements of A Centaur

    Energy Technology Data Exchange (ETDEWEB)

    Stern, S. A.; Schindhelm, E. [Southwest Research Institute, 1050 Walnut Street, Boulder, CO 80302 (United States); Cunningham, N. J., E-mail: astern@swri.edu [Nebraska Wesleyan University, 5000 Saint Paul Avenue, Lincoln, NE 68504 (United States)

    2014-05-01

    We observed the 2600-3200 Å (hereafter, mid-UV) reflectance of two Kuiper Belt Objects (KBOs), two KBO satellites, and a Centaur, using the Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS). Other than measurements of the Pluto system, these constitute the first UV measurements obtained of KBOs, and KBO satellites, and new HST UV measurements of the Centaur 2060 Chiron. We find significant differences among these objects, constrain the sizes and densities of Haumea's satellites, and report the detection of a possible spectral absorption band in Haumea's spectrum near 3050 Å. Comparisons of these objects to previously published UV reflectance measurements of Pluto and Charon are also made here.

  2. Measurement of amino terminal propeptide of type III procollagen (PIIINP) employing the ADVIA Centaur platform. Validation, reference interval and comparison to UniQ RIA

    DEFF Research Database (Denmark)

    Knudsen, Cindy Soendersoe; Heickendorff, Lene; Nexo, Ebba

    2014-01-01

    Background: Recently, measurement of amino terminal propeptide of type III procollagen (PIIINP) was introduced as a part of the hepatic cirrhotic marker enhanced liver fibrosis™ test on the automated ADVIA Centaur® immunoassay platform (Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA). In...

  3. HIRENASD Unstructured Grids - Centaur software

    Data.gov (United States)

    National Aeronautics and Space Administration — These grids were constructed using Centaur software at DLR in Germany. The grids designed for node based (labeled 'cv') and cell-centered solvers (labeled 'cc') are...

  4. Thermal Properties of Centaurs Asbolus and Chiron

    CERN Document Server

    Fernández, Y R; Sheppard, S S

    2002-01-01

    We have measured the mid-infrared thermal continua from two Centaurs, inactive (8405) Asbolus and active 95P=(2060) Chiron, and have constrained their geometric albedos, p, and effective radii, R, with the Standard Thermal Model for slow rotators. These are the first such measurements of Asbolus; we find R=33 km +/- 2 km and p=0.12 +/- 0.03. This albedo is higher than all of those confidently known for active cometary nuclei. The thermal inertia is comparable to or lower than those of main belt asteroids, the Moon, and Chiron; lower than those of the icy Galilean satellites; and much lower than those of near-Earth asteroids. For Chiron, we find R=74 km +/- 4 km and p=0.17 +/- 0.02. While this albedo is consistent with the established value, previous radiometry by others implied a larger radius. This effect may be partially due to a varying infrared dust coma but all datasets have too low signal to be sure. Four Centaur albedos (out of about 30 objects) are now known. They show a diversity greater than that of...

  5. Atlas SOHO Booster and Centaur Erection

    Science.gov (United States)

    1995-01-01

    The launch vehicle for the Solar Heliospheric Observatory (SOHO) mission is a two stage Atlas-IIAS (Atlas/Centaur). The Atlas, consists of a solid rocket booster stage powered by four Thiokol Castor IVA solid rocket boosters (SRB) and a core vehicle stage (booster and sustainer) powered by Rocketdyne MA-5A liquid propellant engines (RP-1 fuel and liquid oxygen). The multiple firing Centaur is powered by two Pratt and Whitney (RL10A-4) liquid hydrogen and liquid oxygen engines with extendible nozzles. This video shows the erection of the Atlas booster and transportation (to 36-B launching pad) and erection of the Centaur.

  6. Radiation flux measuring device

    International Nuclear Information System (INIS)

    A radiation flux measuring device is described which employs an attenuator circuit, the output of which is maintained constant, connected to a radiation detector. Means connected to the attenuator circuit produce an output representing the log of the a-c component of the radiation detector, thereby providing a true root mean square logarithmic output

  7. Radiation flux measuring device

    International Nuclear Information System (INIS)

    A radiation flux measuring device is described which employs a differential pair of transistors, the output of which is maintained constant, connected to a radiation detector. Means connected to the differential pair produce a signal representing the log of the a-c component of the radiation detector, thereby providing a signal representing the true root mean square logarithmic output. 3 claims, 2 figures

  8. Flame Radiation Measurements

    Science.gov (United States)

    Claus, R. W.; Humenik, F. M.; Neely, G. M.

    1983-01-01

    Spectral and total flame radiation measurements exhibited: (1) that radiant heat flux increases with vision combustor inlet air pressure; (2) the effect of fuel atomization characteristics on radiant heat flux; and (3) that a reduction in fuel hydrogen content produces a significant increase in radiant heat flux primarily at low combustor pressures.

  9. Measurement of gravitational radiation

    International Nuclear Information System (INIS)

    The present article first describes some possible principles and mechanisms for detecting the gravitational radiation, and then outlines measuring techniques required for its detection. Some major issues concerned, present status of research and future prospects are also discussed. There are two possible detectors. One is the resonance type detector, which uses an elastic body with a considerable mass as antenna to catch the gravitational radiation. Gravitational radiation entering the elastic body causes an internal stress, resulting in vibration. Thus, a resonance type detector consists of an elastic body acting as antenna to catch gravitational radiation, and a transducer that converts the mechanical vibration of the antenna into electrical signals. The antenna and transducer should be contained in a vacuum highly protected from external acoustic and electromagnetic noise as well as external vibrations. Another possible detector uses a laser interferometer to detect a change in the distance between two bodies caused by gravitational radiation. Some techniques that could provide a tool for measuring such extremely small vibrations are also described and discussed. (N.K.)

  10. Shuttle/Centaur Upper Stage Capability

    Science.gov (United States)

    Clark, H. J.

    1984-01-01

    A joint project to design, develop, procure, and produce Centaur upper stages for use with the Space Shuttle is discussed. A common Centaur G stage 6 meters (19.5 feet) in length is being jointly developed. A longer version designated Centaur G Prime is being developed by NASA to accomplish the Galileo and International Solar-Polar Mission flights in 1986. The Centaur G and G Prime will have the capability to place, respectively, approximately 4540 kilograms (10,000 pounds) and 5910 kilograms (13,000 pounds) into geosynchronous orbit from a standard Shuttle parking orbit of 278 kilometers (150 nautical miles) and Shuttle performance (lift) capability 29,500 kilograms (65,000 pounds). The advent of high energy upper stage capability in 1986 will permit space users and spacecraft developers to utilize spacecraft growth, stage combination concepts with storage modules, teleoperator systems, and other mission peculiar devices to satisfy complex mission demands. These capabilities should greatly enhance the usefulness of the space environment and stimulate mission planners toward conception of innovative means to meet ever increasing mission requirements.

  11. Centaurs as a hazard to civilization

    Science.gov (United States)

    Napier, Bill; Asher, David; Bailey, Mark; Steel, Duncan

    2015-12-01

    Assessments of the risk posed by near-Earth objects ignore the possibility of a giant comet entering the inner solar system. Bill Napier, David Asher, Mark Bailey and Duncan Steel examine the likelihood and potential consequences of the appearance of such a centaur.

  12. Taming Liquid Hydrogen: The Centaur Upper Stage Rocket

    Science.gov (United States)

    2004-01-01

    The Centaur is one of the most powerful rockets in the world. As an upper-stage rocket for the Atlas and Titan boosters it has been a reliable workhorse for NASA for over forty years and has played an essential role in many of NASA's adventures into space. In this CD-ROM you will be able to explore the Centaur's history in various rooms to this virtual museum. Visit the "Movie Theater" to enjoy several video documentaries on the Centaur. Enter the "Interview Booth" to hear and read interviews with scientists and engineers closely responsible for building and operating the rocket. Go to the "Photo Gallery" to look at numerous photos of the rocket throughout its history. Wander into the "Centaur Library" to read various primary documents of the Centaur program. Finally, stop by the "Observation Deck" to watch a virtual Centaur in flight.

  13. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2015-01-01

    This fourth edition reflects recent major developments that have occurred in radiation detector materials, systems, and applications. It continues to provide the most practical and up-to-date introduction to radiation detector technology, proper measurement techniques, and analysis of results for engineers and scientists using radiation sources. New chapters emphasize the expanded use of radiation detection systems in nuclear non-proliferation, homeland security, and nuclear medicine. The book also discusses the correct ways to perform measurements following current health physics procedures.

  14. Radiation protection, measurements and methods

    International Nuclear Information System (INIS)

    The introductory lectures discuss subjects such as radiation protection principles and appropriate measuring techniques; methods, quantities and units in radiation protection measurement; technical equipment; national and international radiation protection standards. The papers presented at the various sessions deal with: Dosimetry of external radiation (27 papers); Working environment monitoring and emission monitoring (21 contributions); Environmental monitoring (19 papers); Incorporation monitoring (9 papers); Detection limits (4 papers); Non-ionizing radiation, measurement of body dose and biological dosimetry (10 papers). All 94 contributions (lectures, compacts and posters) are retrievable as separate records. (HP)

  15. Centaure: an heterogeneous parallel architecture for computer vision

    International Nuclear Information System (INIS)

    This dissertation deals with the architecture of parallel computers dedicated to computer vision. In the first chapter, the problem to be solved is presented, as well as the architecture of the Sympati and Symphonie computers, on which this work is based. The second chapter is about the state of the art of computers and integrated processors that can execute computer vision and image processing codes. The third chapter contains a description of the architecture of Centaure. It has an heterogeneous structure: it is composed of a multiprocessor system based on Analog Devices ADSP21060 Sharc digital signal processor, and of a set of Symphonie computers working in a multi-SIMD fashion. Centaure also has a modular structure. Its basic node is composed of one Symphonie computer, tightly coupled to a Sharc thanks to a dual ported memory. The nodes of Centaure are linked together by the Sharc communication links. The last chapter deals with a performance validation of Centaure. The execution times on Symphonie and on Centaure of a benchmark which is typical of industrial vision, are presented and compared. In the first place, these results show that the basic node of Centaure allows a faster execution than Symphonie, and that increasing the size of the tested computer leads to a better speed-up with Centaure than with Symphonie. In the second place, these results validate the choice of running the low level structure of Centaure in a multi- SIMD fashion. (author)

  16. Radiation detector device for measuring ionizing radiation

    International Nuclear Information System (INIS)

    The device contains a compensating filter circuit, which guarantees measurement of the radiation dose independent of the energy or independent of the energy and direction. The compensating filter circuit contains a carrier tube of a slightly absorbing metal with an order number not higher than 35, which surrounds a tubular detector and which carries several annular filter parts on its surface. (orig./HP)

  17. Solar and infrared radiation measurements

    CERN Document Server

    Vignola, Frank; Michalsky, Joseph

    2012-01-01

    The rather specialized field of solar and infrared radiation measurement has become more and more important in the face of growing demands by the renewable energy and climate change research communities for data that are more accurate and have increased temporal and spatial resolution. Updating decades of acquired knowledge in the field, Solar and Infrared Radiation Measurements details the strengths and weaknesses of instruments used to conduct such solar and infrared radiation measurements. Topics covered include: Radiometer design and performance Equipment calibration, installation, operati

  18. Atmospheric Radiation Measurement Program plan

    International Nuclear Information System (INIS)

    In order to understand energy's role in anthropogenic global climate change, significant reliance is being placed on General Circulation Models (GCMs). A major goal is to foster the development of GCMs capable of predicting the timing and magnitude of greenhouse gas-induced global warming and the regional effects of such warming. The Atmospheric Radiation Measurement (ARM) Program will contribute to the Department of Energy goal by improving the treatment of cloud radiative forcing and feedbacks in GCMs. Two issues will be addressed: the radiation budget and its spectral dependence and the radiative and other properties of clouds. The experimental objective of the ARM Program is to characterize empirically the radiative processes in the Earth's atmosphere with improved resolution and accuracy. A key to this characterization is the effective treatment of cloud formation and cloud properties in GCMs. Through this characterization of radiative properties, it will be possible to understand both the forcing and feedback effects. 19 refs., 4 figs., 2 tabs

  19. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2011-01-01

    This is an update of the standard textbook for the field of radiation measurement. It includes illustrative examples and new problems. The research and applications of nuclear instrumentation have grown substantially since publication of the previous editions. With the miniaturization of equipment, increased speed of electronic components, and more sophisticated software, radiation detection systems are now more productively used in many disciplines, including nuclear nonproliferation, homeland security, and nuclear medicine. Continuing in the tradition of its bestselling predecessors, "Measurement and Detection of Radiation, Third Edition" illustrates the fundamentals of nuclear interactions and radiation detection with a multitude of examples and problems. It offers a clearly written, accessible introduction to nuclear instrumentation concepts. The following are new to the third edition: a new chapter on the latest applications of radiation detection, covering nuclear medicine, dosimetry, health physics, no...

  20. Nuclear instrumentation for radiation measurement

    International Nuclear Information System (INIS)

    Nuclear radiation cannot be detected by human senses. Nuclear detectors and associated electronics facilitate detection and measurement of different types of radiation like alpha particles, beta particles, gamma radiation, and detection of neutrons. Nuclear instrumentation has evolved greatly since the discovery of radioactivity. There has been tremendous advancement in detector technology, electronics, computer technology, and development of efficient algorithms and methods for spectral processing to extract precisely qualitative and quantitative information of the radiation. Various types of detectors and nuclear instruments are presently available and are used for different applications. This paper describes nuclear radiation, its detection and measurement and associated electronics, spectral information extraction, and advances in these fields. The paper also describes challenges in this field

  1. Radiation measurements and quality control

    International Nuclear Information System (INIS)

    Accurate measurements are essential to research leading to a successful radiation process and to the commissioning of the process and the facility. On the other hand, once the process is in production, the importance to quality control of measuring radiation quantities (i.e., absorbed dose, dose rate, dose distribution) rather than various other parameters of the process (i.e. conveyor speed, dwell time, radiation field characteristics, product dimensions) is not clearly established. When the safety of the product is determined by the magnitude of the administered dose, as in radiation sterilization, waste control, or food preservation, accuracy and precision of the measurement of the effective dose are vital. Since physical dose measurements are usually simpler, more reliable and reproducible than biological testing of the product, there is a trend toward using standardized dosimetry for quality control of some processes. In many industrial products, however, such as vulcanized rubber, textiles, plastics, coatings, films, wire and cable, the effective dose can be controlled satisfactorily by controlling process variables or by product testing itself. In the measurement of radiation dose profiles by dosimetry, it is necessary to have suitable dose meter calibrations, to account for sources of error and imprecision, and to use correct statistical procedures in specifying dwell times or conveyor speeds and source and product parameters to achieve minimum and maximum doses within specifications. (author)

  2. Current topics in radiation measurements

    International Nuclear Information System (INIS)

    Current research topics in radiation measurements will be shown in this presentation. Applications of radiation measurements have grown with the development of radiation sources and new measurement techniques. Recent new developments in this field are briefly introduced. Optical techniques such as lasers and fiber optics, which are widely used in an optical communication field, are successfully applied to radiation measurements. Micro-fabrication techniques and the photolithography technique are indispensable for semiconductor or even gas detectors. Complicated analog signal processing is being simplified by the use of fast computation techniques available in digital chips. Cryogenic X-ray detectors are making a great progress in the energy resolution. Some of the current research topics found in the recent journals and international symposiums are as follows: the development of room temperature semiconductor radiation detectors like CdZnTe and SiC, new signal processing methods such as coplanar grid unipolar charge sensing, medical γ-ray imaging, the development of cryogenic X-ray detectors such as STJs (Superconducting Tunnel Junction) and TES (Transition Edge Sensor) microcalorimeters, micromachined gas proportional counters like MSGC/MGC/GEM, new detection system which requires both the energy and spatial resolutions, the search of longer wavelength scintillators, development of new fast scintillators such as LSO/YAP/LuAP, new digital waveform processing based on fast digitizing technique, etc. Current developments are especially focused on the increase of the information derived from the detector and the improvement in the resolution. One of the other directions of the development is toward the microscopic visualization of the radiation. Such an approach must solve many technological difficulties both in fabrication of the detectors and even in the detection scheme, however, we might proceed to open a new phase of radiation measurements soon. (author)

  3. Quality assurance in radiation measurement

    International Nuclear Information System (INIS)

    The achievement of traceability to recognize measurement standards for ionizing radiation posses special requirements. Methods of transferring reference standard to the working situation are devised through calibration and appropriate traceability, which optimize the accuracy attainable with the method of dose determination in routine use. Appropriate procedures are developed by the SSDL-MINT to establish accurate dose measurement in wide range of radiation fields such as in medicine, agriculture and industrial application. The status of work including effort towards ISO 9000 certification of SSDL dosimetry services will be summarized. (Author)

  4. Radiation measurements and quality control

    International Nuclear Information System (INIS)

    The association between radiation measurements and quality control is established for radiation sterilization of medical products and food irradiation. Good quality control implies accurate radiation dosimetry and a discussion of the factors which can affect the accuracy of in-plant dosimetry is presented. It is argued that if systematic errors are to be avoided in in-plant dosimetry the plant operators will have to spend more time and effort in developing the skills associated with the accurate use of radiation dosemeter systems. The aims and merits of an international intercomparison programme recently set up by the IAEA are discussed. The benefits of accurate in-plant dosimetry for the operator, approving authority and purchaser are balanced against the extra dosimetric efforts required for good quality control. (author)

  5. Atmospheric Radiation Measurement Program Plan

    International Nuclear Information System (INIS)

    In order to understand energy's role in anthropogenic global climate change, significant reliance is being placed on General Circulation Models (GCMs). A major goal of the Department is to foster the development of GCMs capable of predicting the timing and magnitude of greenhouse gas-induced global warming and the regional effects of such warming. DOE research has revealed that cloud radiative feedback is the single most important effect determining the magnitude of possible climate responses to human activity. However, cloud radiative forcing and feedbacks are not understood at the levels needed for reliable climate prediction. The Atmospheric Radiation Measurement (ARM) Program will contribute to the DOE goal by improving the treatment of cloud radiative forcing and feedbacks in GCMs. Two issues will be addressed: the radiation budget and its spectral dependence and the radiative and other properties of clouds. Understanding cloud properties and how to predict them is critical because cloud properties may very well change as climate changes. The experimental objective of the ARM Program is to characterize empirically the radiative processes in the Earth's atmosphere with improved resolution and accuracy. A key to this characterization is the effective treatment of cloud formation and cloud properties in GCMs. Through this characterization of radiative properties, it will be possible to understand both the forcing and feedback effects. GCM modelers will then be able to better identify the best approaches to improved parameterizations of radiative transfer effects. This is expected to greatly improve the accuracy of long-term, GCM predictions and the efficacy of those predictions at the important regional scale, as the research community and DOE attempt to understand the effects of greenhouse gas emissions on the Earth's climate. 153 refs., 24 figs., 6 tabs

  6. Radiochromic technique for radiation measurements

    International Nuclear Information System (INIS)

    he radio-chromic technique in radiation dosimetry for protection of patients and occupational workers are known to health physicist and dosimetrist since long. But with the recent advances in polymer science, measurement techniques and understanding of physical phenomenon responsible for color change on radiation sensitive objects, the technique is progressing very well for personal accidental dose measurements, online dose mapping of patients during radiotherapy treatment without any further processing, and radiation industries. These dosimeters, with very high spatial resolution and relatively low spectral sensitivity variation, are insensitive to visible light, thus offering ease of handling. Radiochromic dosimeters color directly and do not require chemical processing wherein a color change (colorless to blue, red, green, etc.) indicates exposure to radiation. Image formation occurs as a dye-forming or a polymerization process, in which energy is transferred from an energetic photon or particle to the receptive part of the leuco-dye or colorless photomonomer molecule, initiating color formation through chemical changes. In recent years, various radiochromic dosimeters have also been used for nonclinical applications such as blood irradiation, radiation processing, and reference standard. The Paper highlights the national and international status of the techniques including responsible physical - chemical phenomenon, standard commercial products with its futuristic applications for mapping of radiation doses and radiation dose estimation in nuclear/radiological emergency. The Paper highlights the R and D efforts carried out at DLJ to establish radiochromic techniques based on radiochromic dyes and substituted diacytelene first time in India. The radiochromic films based on pH sensitive dyes, leuco dyes and substituted diacytelene using a suitable polymer as a host matrix has been developed at DLJ and characterized using standard techniques. The radiochromic

  7. Shuttle Centaur engine cooldown evaluation and effects of expanded inlets on start transient

    Science.gov (United States)

    1987-01-01

    As part of the integration of the RL10 engine into the Shuttle Centaur vehicle, a satisfactory method of conditioning the engine to operating temperatures had to be established. This procedure, known as cooldown, is different from the existing Atlas Centaur due to vehicle configuration and mission profile differenced. The program is described, and the results of a Shuttle Centaur cooldown program are reported. Mission peculiarities cause substantial variation in propellant inlet conditions between the substantiated Atlas Centaur and Shuttle Centaur with the Shuttle Centaur having much larger variation in conditions. A test program was conducted to demonstrate operation of the RL10 engine over the expanded inlet conditions. As a result of this program, the Shuttle Centaur requirements were proven satisfactory. Minor configuration changes incorporated as a result of this program provide substantial reduction in cooldown propellant consumption.

  8. Equipment for measuring radiation. Part 3. Technique of measuring radiation

    Energy Technology Data Exchange (ETDEWEB)

    Radwanowski, L.J.

    1979-01-01

    Difficulties are noted in measuring the effects of radiation because of the excessively low energy of the measured fields. In nature there are different magnetic-dynamic and magnetic-hydrodynamic generators which are sources of very low intensity which changes in time. The equipment of measurements is examined in the example of one of the generators, underground water current. The apparatus is described in detail for measuring the intensity of the electromagnetic SHF field. Under the underground water currents a change is observed in the intensity of the electromagnetic field. The possibilities are also examined of direct measurement of ultrasonic elastic fluctuations caused by the underground current, as well as the possibility of recording other physical fields (spontaneous polarization, soil temperature). A study was made of the effect of the underground water current on the occurrence of physical, chemical and biological processes: photochemical reactions, reactions of metal oxidation, Golomb effect (change in the rate of sedimentation of argillaceous particles in water under the influence of a biofield), change in air humidity and soil water content, change in intensity of the magnetic field, Hall effect, change in luminescence of certain organisms or the luminophore released by them. Basic plans are presented of certain measurement and recording devices.

  9. Evaluation of arctic broadband surface radiation measurements

    OpenAIRE

    Matsui, N.; C. N. Long; J. Augustine; Halliwell, D.; T. Uttal; Longenecker, D.; O. Nievergall; Wendell, J.; Albee, R.

    2011-01-01

    The Arctic is a challenging environment for making in-situ radiation measurements. A standard suite of radiation sensors is typically designed to measure the total, direct and diffuse components of incoming and outgoing broadband shortwave (SW) and broadband thermal infrared, or longwave (LW) radiation. Enhancements can include various sensors for measuring irradiance in various narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are...

  10. Evaluation of Arctic broadband surface radiation measurements

    OpenAIRE

    Matsui, N.; C. N. Long; J. Augustine; Halliwell, D.; T. Uttal; Longenecker, D.; Niebergall, O.; Wendell, J.; Albee, R.

    2012-01-01

    The Arctic is a challenging environment for making in-situ surface radiation measurements. A standard suite of radiation sensors is typically designed to measure incoming and outgoing shortwave (SW) and thermal infrared, or longwave (LW), radiation. Enhancements may include various sensors for measuring irradiance in narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are mounted on complex mechanical platforms (solar trackers) that ...

  11. Ambient radiation exposure: measurements and effects

    International Nuclear Information System (INIS)

    A brief review of the available literature, data and reports of various radiation exposure and protection studies and various measurements techniques are presented. A linear quadratic model has been given illustrating the validity of radiation hormesis

  12. Assessing the contribution of Centaur impacts to ice giant luminosities

    OpenAIRE

    Dodson-Robinson, Sarah E.

    2015-01-01

    Voyager 2 observations revealed that the internal luminosity of Neptune is an order of magnitude higher than that of Uranus. If the two planets have similar interior structures and cooling histories, the luminosity of Neptune can only be explained by invoking some energy source beyond gravitational contraction. This paper investigates whether Centaur impacts could provide the energy necessary to produce the luminosity of Neptune. The major findings are (1) that impacts on both Uranus and Nept...

  13. Measurement of radiation damage on silica aerogel Cerenkov radiator

    CERN Document Server

    Sahu, S K; Suda, R; Enomoto, R; Peng, K C; Wang, C H; Adachi, I; Amami, M; Chang, Y H; Guo, R S; Hayashi, K; Iijima, T; Sumiyoshi, T; Yoshida, Y

    1996-01-01

    We measured the radiation damage on silica aerogel \\v Cerenkov radiators originally developed for the B-factory experiment at KEK. Refractive index of the aerogel samples ranged from 1.012 to 1.028. The samples were irradiated up to 9.8~MRad of equivalent dose. Measurements of transmittance and refractive index were carried out and these samples were found to be radiation hard. Deteriorations in transparency and changes of refractive index were observed to be less than 1.3\\% and 0.001 at 90\\% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed.

  14. Measurement of radiation damage on a silica aerogel Cherenkov radiator

    International Nuclear Information System (INIS)

    We measured the radiation damage on silica aerogel Cherenkov radiators originally developed for the B-factory experiment at KEK. The refractive index of the aerogel samples ranged from 1.012 to 1.028. The samples were irradiated up to 9.8 Mrad of equivalent dose. Measurements of transmittance and refractive index were carried out and these samples were found to be radiation hard. Deteriorations in transparency and changes of refractive index were observed to be less than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. (orig.)

  15. Large retrograde Centaurs: visitors from the Oort cloud?

    CERN Document Server

    Marcos, C de la Fuente

    2014-01-01

    Among all the asteroid dynamical groups, Centaurs have the highest fraction of objects moving in retrograde orbits. The distribution in absolute magnitude, H, of known retrograde Centaurs with semi-major axes in the range 6-34 AU exhibits a remarkable trend: 10% have H 12 mag. The largest objects, namely (342842) 2008 YB3, 2011 MM4 and 2013 LU28, move in almost polar, very eccentric paths; their nodal points are currently located near perihelion and aphelion. In the group of retrograde Centaurs, they are obvious outliers both in terms of dynamics and size. Here, we show that these objects are also trapped in retrograde resonances that make them unstable. Asteroid 2013 LU28, the largest, is a candidate transient co-orbital to Uranus and it may be a recent visitor from the trans-Neptunian region. Asteroids 342842 and 2011 MM4 are temporarily submitted to various high-order retrograde resonances with the Jovian planets but 342842 may be ejected towards the trans-Neptunian region within the next few hundred kyr....

  16. Extra-red transneptunian objects and Centaurs: Composition and chemical history

    Science.gov (United States)

    Dalle Ore, C. M.; Barucci, M. A.; Cruikshank, D. P.; Emery, J. P.

    2014-07-01

    We present the results of a systematic analysis of the surface composition of ten of the reddest transneptunian objects (TNOs). The goal of the analysis is to determine the current chemical compositions of these extra-red objects and investigate possible paths of chemical evolution since formation. The sample consists of six objects from the classical and resonant populations, one detached object, and three Centaurs. The classical and resonant objects are expected to be similar to each other in composition, while the surfaces of the three Centaurs could have been significantly modified as their orbits evolved. Furthermore, Brown et al. (Brown, M.E., Schaller, E.L., & Fraser, W.C., 2011. A Hypothesis for the Color Diversity of the Kuiper Belt. ApJL, 739, L60) propose that objects with red color are rich in methanol. The available data consist of broad-band photometric measurements in the wavelength range between 0.3 and 4.5 μ m. The photometric measurements are scaled to the albedo at 0.55 μ m to yield an approximation of the spectral shape of each object that is then compared to a library of synthetic spectra of mixtures of materials known to be present on the surfaces of TNOs. Errors as well as phase-angle differences are taken into account as part of the fitting uncertainty. For each object, we obtain a range of compositions that match their spectral distribution within the estimated errors. This yields the likelihood for the various materials to be present on the surface as well as a rough measure of the uncertainty of the estimate. All objects show presence of methanol and/or methane on their surface, supporting the Brown et al. (2011) hypothesis. To further analyze our results, ices are grouped into 'stable' (H_2O), 'partially stable' (CH_3OH, CO_2), and 'volatile' (CH_4, CO, N_2). Our results show some difference in the amount of 'volatile' and 'partially stable' ices among the classical and resonant objects. A trend in the sense of less ice present on

  17. Relations between radiation risks and radiation protection measuring techniques

    International Nuclear Information System (INIS)

    Relations between radiation risks and radiation protection measuring techniques are considered as components of the radiation risk. The influence of the exposure risk on type and extent of radiation protection measurements is discussed with regard to different measuring tasks. Based upon measuring results concerning the frequency of certain external and internal occupational exposures in the GDR, it has been shown that only a small fraction of the monitored persons are subjected to a high exposure risk. As a consequence the following recommendations are presented: occupationally exposed persons with small exposure risk should be monitored using only a long-term desimeter (for instance a thermoluminescence desimeter). In the case of internal exposure, the surface and air contamination levels should be controlled so strictly that routine measurements of internal contamination need not be performed

  18. The design and fabrication of the Centaur neutral buoyancy trainer and related hardware

    Science.gov (United States)

    Ware, Alan S.; Hollingsworth, Michael

    1986-01-01

    Two full scale mockups of the Centaur upper stage were designed, fabricated and delivered to NASA. One was the Centaur Weightless Environment Training Facility (WETF) trainer and the other was the Centaur 1-G mockup. The Centaur upper stage booster is designed to carry the spacecraft Galileo to Jupiter, and the spacecraft Ulysses to an orbit around the Sun after launch from the Space Shuttle. The flight vehicle has several Extravehicular Activity (EVA) contingency tasks that require crew training. This need for crew training generated the requirement for the Centaur WETF crew trainer, which is high fidelity in areas of expected crew interface. During the production of the Centaur WETF crew trainer, the need for a jumper cable from Centaur to the Orbiter was identified. This EVA contingency task would be the installation of a cable from the Orbiter cargo bay sill to various command data boxes on Centaur to allow crew control deployment should a failure occur. This task required the upgrading of volumetric boxes on the trainer to a high fidelity configuration including electrical connector installation and cable routing.

  19. RL10 Engine Ability to Transition from Atlas to Shuttle/Centaur Program

    Science.gov (United States)

    Baumeister, Joseph F.

    2015-01-01

    A key launch vehicle design feature is the ability to take advantage of new technologies while minimizing expensive and time consuming development and test programs. With successful space launch experiences and the unique features of both the National Aeronautics and Space Administration (NASA) Space Transportation System (Space Shuttle) and Atlas/Centaur programs, it became attractive to leverage these capabilities. The Shuttle/Centaur Program was created to transition the existing Centaur vehicle to be launched from the Space Shuttle cargo bay. This provided the ability to launch heaver and larger payloads, and take advantage of new unique launch operational capabilities. A successful Shuttle/Centaur Program required the Centaur main propulsion system to quickly accommodate the new operating conditions for two new Shuttle/Centaur configurations and evolve to function in the human Space Shuttle environment. This paper describes the transition of the Atlas/Centaur RL10 engine to the Shuttle/Centaur configurations; shows the unique versatility and capability of the engine; and highlights the importance of ground testing. Propulsion testing outcomes emphasize the value added benefits of testing heritage hardware and the significant impact to existing and future programs.

  20. Measurement of gamma radiation around base station

    International Nuclear Information System (INIS)

    The ? -radiation have been measured around base station in Isparta region of Turkey to see the contribution of base station on the background radiation. Isparta which is surrounded by high mountain of Davras is located at southern part of Turkey. There are several volcanic activity in this region. The background radiation arises from two main sources. These are natural and technological sources. The natural radiation are mainly contributed by cosmic rays and terrestrial radiation. Cosmic rays comes from outside of the atmosphere after supernova explosion in the universe. The radiation comes direct from outside of atmosphere called primer cosmic rays and some of them can create seconder particle such as neutron.proton etc after some reaction with the oxygen, nitrogen etc in the atmosphere. The origin of terrestrial radiation are some radionucleus in rocks and soils. These are mainly 40K, 238U, 232Th and their products. The terrestrial radiation depends on geological structure of the region. The other types of γ-radiation is technological origin. With the development of technology in many different fields radiation can be produced. Nowadays mobile phones are widely used technological device and this requires base station to be established around habitable area. The electromagnetic radiations from base station and its effect are always a big question in people's mind and this would be investigated. The measurement have been performed using ASP/2e counter connected to a sing NaI(Tl) γ-ray detector. It was done around five different base station and also different altitude in Davraz mountain. The radiation dose from ambient air over five months ranges from 50 to 140 nGy h-1. The contribution of base station to the natural background radiation was clearly seen in the measurement

  1. A photometric search for activity among asteroids and Centaurs

    Science.gov (United States)

    Sosa Oyarzabal, A.; Mammana, L.; Fernández, J. A.

    2014-07-01

    We present the first results of a long-term observational campaign focused on the detection of activity in selected asteroids and centaurs. Our observational targets are near-Earth asteroids in cometary orbits (cf. [2]), the so called ''main-belt comets'' or ''active asteroids'' (well-known objects as well as potential candidates), and bright centaurs with good orbits, all close to their perihelion passages. In those objects with a former detection of activity, our aim is to contribute to a better physical knowledge of them, and determine, for instance, if the observed activity is transient or permanent. To achieve our goals, we analyzed CCD-filtered images of each observable target acquired with the 2.15-m telescope ''Jorge Sahade'' at CASLEO (San Juan, Argentina), during two runs of three consecutive nights each (during August 2013 and January 2014, respectively). Our study will be completed by future runs with the same instrumentation already assigned to our campaign. As preliminary results, we observed activity in the main-belt comets P/2013 P5 (PANSTARRS) and 133P/(7968) Elst-Pizarro. We also observed the main-belt comet (596) Scheila, which showed an unequivocally stellar appearance. We observed the main-belt comet candidate (3646) Aduatiques (cf. [1]), and noticed in this object a curious feature whose connection to some kind of activity is not well determined yet. We also observed the near-Earth asteroid in cometary orbit 2006 XL_5 (cf. [3]), and the centaurs (281371) 2008 FC_{76}, (332685) 2009 HH_{36}), (382004) 2010 RM_{64}, 2010 XZ_{78}, and 2011 UR_{402}. We have not detected activity in these objects, but an improved analysis is still in progress. %Corresponding author: Andrea Sosa (asosa@fisica.edu.uy)

  2. Measuring transient radiation effects in optical fibers

    International Nuclear Information System (INIS)

    We propose a new method for measuring transient radiation effects in optical fibers on a nanosecond timescale. The method, which incorporates a streak camera, allows more precise time resolution than other methods and has the advantage of measuring the radiation-induced attenuation as a function of wavelength and time simultaneously. By choosing different light sources and sweep speeds, radiation-induced attenuation may be measured under a variety of experimental configurations. Examples of the type of output obtained with our method are given

  3. Radiation protection: Measurement, modelling, documentation. Proceedings

    International Nuclear Information System (INIS)

    The focus of this conference is on the practical aspects of radiation protection and embraces a ''core business'' of radiation protection, namely: measuring, modeling, documentation, and all the activities and good professional practices in this context. The radiation protection experts and the radiation safety officers who contributed papers to this conference are ''practitioners'' in their fields. To round up the subject matter, there are papers dealing with legal aspects, elaborating on recent regulatory provisions and requirements, and papers dicsussing new approaches in designing and disseminating information to the public. (orig./CB)

  4. Solid rocket motor integration on the Atlas/Centaur launch vehicle

    Science.gov (United States)

    Arnett, Stephen E.

    1993-06-01

    The structural design, development, and verification testing required to integrate solid rocket motors (SRM) on the Atlas IIAS launch vehicle is described. It is concluded that the next generation Atlas Centaur based on four strap-on Castor IVA SRMs and capable of lifting 7700 pounds to geosynchronous orbit has undergone a rigorous development program. A new system intended to mount and jettison the SRMs from the core vehicle is characterized by robustness and ease of installation. To insulate the aft end of the vehicle against increased SRM-induced heat fluxes and to seal against ingress of potentially hazardous base gases extensive measures were undertaken. They include nonporous engine boots and a thrust section compartment passive pressurization system.

  5. TEPC measurements in different radiation fields

    International Nuclear Information System (INIS)

    Some experimental results of measurements using tissue-equivalent proportional counters are given. Spectra of neutrons with different energies, gamma radiation and protons were measured. The LET spectra which constitute the test results can be used for gaining a better physical understanding and interpretation of the effects that mixed neutron-gamma radiation field would exert in the tissue. The LET spectra are also used to calibrate the detector for a wider range of particles and energies. ( M.D.)

  6. Phantoms for Radiation Measurements of Mobile Phones

    DEFF Research Database (Denmark)

    Pedersen, Gert Frølund

    2001-01-01

    Measurements of radiation efficiency for a handheld phone equipped with a patch and a helical antenna operated near the human user have been performed. Both measurements include a simple head plus hand phantom and live persons are considered. The position of the hand on the phone is found to be the...... main reason for the large variation in radiation efficiency among persons. The tilt angle of the phone and the distance between the head and phone only play a minor role...

  7. Web based Measurement System for Solar Radiation

    OpenAIRE

    Shachi Awasthi; Dr. P. Mor

    2012-01-01

    We present in this paper, the principles of the measurement system for solar radiation, and our implementation using Web based data logging concept. The photocurrent produced by Silicon PN junction is used as a solar radiation transducer, to make it more viable we have used commercially available solar panels as our transducers. Using a silicon solar cell as sensor, a low cost solar radiometer can be constructed. The photocurrent produced by solar cell is electronically tailored to be measure...

  8. Digital measurement of radiation using FPGA

    International Nuclear Information System (INIS)

    Recently radiation survey meters and radiation monitors which have advanced information transmission function are available for radiation safety management. They are equipped with the digital spectrometer which can identify radioactive nuclides, the global positioning system and so on. The digital-signal processing technology of a high order is necessary for the operation of these advanced instruments. Nowadays FPGA (Field Programmable Gate Array: Logical gate array that can be revised on site) is effectively used instead of ASIC (Integrated circuit for specific purpose) which needs much expense to be developed. One can flexibly build digital-signal processing circuits by using FPGA. We describe the progress of radiation measurement technology using FPGA putting emphasis on the radiation spectrum measurement technology. (J.P.N.)

  9. Ionizing radiation in industrial measurements

    International Nuclear Information System (INIS)

    The development of instruments for industrial measurements have been extensively reviewed. Especially the measuring systems for control and automation as well as industrial radiometric gages have been presented and their application in Poland and other countries have been shown. The future developing trends in the interesting branch has been discussed

  10. Radiation transmission pipe thickness measurement system

    International Nuclear Information System (INIS)

    Fuji Electric Systems can be measured from the outer insulation of the transmission Characteristics and radiation detection equipment had been developed that can measure pipe wall thinning in plant and running, the recruitment of another three-beam calculation method by pipe thickness measurement system was developed to measure the thickness of the pipe side. This equipment has been possible to measure the thickness of the circumferential profile of the pipe attachment by adopting automatic rotation. (author)

  11. On output measurements via radiation pressure

    DEFF Research Database (Denmark)

    Leeman, S.; Healey, A.J.; Forsberg, F.; Jensen, J.A.

    It is shown, by simple physical argument, that measurements of intensity with a radiation pressure balance should not agree with those based on calorimetric techniques. The conclusion is ultimately a consequence of the circumstance that radiation pressure measurements relate to wave momentum, while...... calorimetric methods relate to wave energy. Measurements with some typical ultrasound fields are performed with a novel type of hydrophone, and these allow an estimate to be made of the magnitude of the discrepancy to be expected between the two types of output measurement in a typical case....

  12. Exposure of Finnish population to ultraviolet radiation and radiation measurements

    International Nuclear Information System (INIS)

    This report is based on a survey of the literature on radiation risks involved in sunbathing and the use of solaria. The purpose of the report is to provide background information for the development of regulations on solaria and for informing the public about the risks posed by solaria and the sun. The report gives an overview of the properties and biological effects of ultraviolet radiation. The most important regulations and recommendations issued in various countries are presented. The connection between ultraviolet radiation and the risks of skin cancer is examined both on a general level and in reference to information obtained from the Finnish Cancer Registry. In Finland, the incidence of melanomas nearly tripled between 1960 and 1980. The most important cause is considered to be the population's increased exposure to the su's ultraviolet radiation. There are no reliable data on the connection between the use of solaria and the risks of skin cancer. It is estimated, however, that solaria account for less than 10 per cent of the skin cancer risk of the whole population. There are some difficult physical problems associated with the measurement of ultraviolet radiation emitted by both natural sources and solaria. A preliminary study of these problems has been undertaken by means of a survey of the available literature, supplemented by a review of measurements performed by the Finnish Centre For Radiation and Nuclear Safety. The estimated inaccuracy of the Optronic 742 spectroradiometer used by the Centre in the measurement of ultraviolet radiation emitted by the sun and solaria is about +-14%

  13. Computational methods for industrial radiation measurement applications

    International Nuclear Information System (INIS)

    Computational methods have been used with considerable success to complement radiation measurements in solving a wide range of industrial problems. The almost exponential growth of computer capability and applications in the last few years leads to a open-quotes black boxclose quotes mentality for radiation measurement applications. If a black box is defined as any radiation measurement device that is capable of measuring the parameters of interest when a wide range of operating and sample conditions may occur, then the development of computational methods for industrial radiation measurement applications should now be focused on the black box approach and the deduction of properties of interest from the response with acceptable accuracy and reasonable efficiency. Nowadays, increasingly better understanding of radiation physical processes, more accurate and complete fundamental physical data, and more advanced modeling and software/hardware techniques have made it possible to make giant strides in that direction with new ideas implemented with computer software. The Center for Engineering Applications of Radioisotopes (CEAR) at North Carolina State University has been working on a variety of projects in the area of radiation analyzers and gauges for accomplishing this for quite some time, and they are discussed here with emphasis on current accomplishments

  14. Radiation distribution measurements in Fukushima prefecture

    International Nuclear Information System (INIS)

    On March 11, 2011, a huge tsunami caused by the Great East Japan Earthquake destroyed all the electrical power facilities in the Fukushima Daiichi nuclear power plant. As a result, the reactors were badly damaged, and radioactive particles were widely scattered in the surrounding areas. In order to study the behavior of the radioactive particles emitted from the Fukushima Daiichi nuclear power plant, different measurement tools were developed. This paper describes two types of wireless radiation sensor networks and a two-dimensional radiation-level mapping system using a radio-controlled multi-copter. The measurements were analyzed, and the following conclusions were made regarding the radioactive particle distribution and its variation with time. (1) Radiation level has gradually decreased with time. (2) The rate of decrease in radiation is faster than that calculated from the half-life. (3) The radiation-level distribution is not uniform and sharply varies even within short distances such as tens of meters. (4) The locations of the hot spots have not changed, and the peak radiation levels are constantly decreasing. By using two-dimensional maps, the radiation levels can be lowered more effectively by selectively removing the highly radioactive materials. The residents can also use the map to reduce their exposure to radiation by avoiding hot spots. (author)

  15. All terrain robot for remote radiation measurement

    International Nuclear Information System (INIS)

    In view of recent nuclear accidents like that in Fukushima Daiichi, the necessity for remote radiation measurement, as a first step in crisis management has been felt in the nuclear technology community. Also, some regular maintenance works in nuclear facilities result in substantial radiation exposure to human workers. All these have provided an impetus to the development of an All-Terrain Robot capable of remote radiation mapping inside nuclear installations; accordingly a prototype system has been developed at DRHR, Bhabha Atomic Research Centre. This robot has been designed to negotiate uneven terrain including staircases. Also, the robot is equipped with three onboard cameras and a retractable radiation detector and it is remotely controlled over wireless communication links with a computer. The control software, through its seamless interface, allows for easy viewing and logging of radiation data in real time. The system has been deployed and field trials have been taken

  16. Radiation protection measurement. Philosophy and implementation

    International Nuclear Information System (INIS)

    A selection from the proceedings of the International Symposium held by the U.K. Society for radiological protection in June 1974 was presented. The central theme was the philosophy of radiation protection measurement and its interpretation although some specific areas of good health physics practice were included. The 28 papers selected were chosen to be either representative of the central theme or of wider interest. The papers have been grouped in 6 main sections: philosophy of measurements; interpretation of measurements; implementation by legislation and monitoring; radiation exposure and control; reactor safety and siting; accidents

  17. A radiation measurement study on cellular phone

    International Nuclear Information System (INIS)

    This paper will explain the radiation level produced by various selected cellular phone from various models and brands available in the market. The result obtained from this study will also recommend whether a cellular phone is safe for public usage or it might cause any effect on public health. Finally, a database of radiation measurement level produced by selected various cellular phone will also be developed and exhibited in this paper. (Author)

  18. MSL-RAD radiation environment measurements.

    Science.gov (United States)

    Guo, Jingnan; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Hassler, Donald M; Ehresmann, Bent; Köhler, Jan; Böhm, Eckart; Böttcher, Stephan; Brinza, David; Burmeister, Sönke; Cucinotta, Francis; Martin, Cesar; Posner, Arik; Rafkin, Scot; Reitz, Guenther

    2015-09-01

    In this study, results are presented from the on-board radiation assessment detector (RAD) of Mars Science Laboratory (MSL). RAD is designed to measure the energetic particle radiation environment, which consists of galactic cosmic rays (GCRs) and solar energetic particles (SEPs) as well as secondary particles created by nuclear interactions of primary particles in the shielding (during cruise) or Martian soil and atmosphere (surface measurements). During the cruise, RAD collected data on space radiation from inside the craft, thus allowing for a reasonable estimation of what a human crew travelling to/from Mars might be exposed to. On the surface of Mars, RAD is shielded by the atmosphere (from above) and the planet itself (from below). RAD measures the first detailed radiation data from the surface of another planet, and they are highly relevant for planning future crewed missions. The results for radiation dose and dose equivalent (a quantity most directly related to human health risk) are presented during the cruise phase, as well as on the Martian surface. Dose and dose equivalent are dominated by the continuous GCR radiation, but several SEP events were also detected and are discussed here. PMID:25969529

  19. Measurement of $\\psip$ Radiative Decays

    OpenAIRE

    Ablikim, M.; Bai, J. Z.; Y. Ban; Collaboration, BES

    2006-01-01

    Using 14 million psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gamma ppbar, gamma 2(pi^+pi^-), gamma K_s K^-pi^++c.c., gamma K^+ K^- pi^+pi^-, gamma K^{*0} K^- pi^+ +c.c., gamma K^{*0}\\bar K^{*0}, gamma pi^+pi^- p pbar, gamma 2(K^+K^-), gamma 3(pi^+pi^-), and gamma 2(pi^+pi^-)K^+K^- with the invariant mass of hadrons below 2.9GeV/c^2. We also report branching fractions of psi(2S) decays into 2(pi^+...

  20. Recent measurements of coherent transition radiation

    International Nuclear Information System (INIS)

    An extended series of experiments has been used to investigate transition radiation in the x-ray spectral region. The x-rays were generated at the Lawrence Livermore National Laboratory electron-positron linear accelerator by 54 MeV electrons traversing multiple thin-foil targets. The measured angular and spectral distributions have shown excellent agreement with calculated predictions based on a simplified theoretical description of transition radiation. Recently, energy-resolved measurements of x-ray generation by targets consisting of multiple closely-spaced foils has clearly demonstrated the longitudinal coherence of transition radiation. This behavior might lead to a variety of applications such as tuneable narrow-band x-ray sources, measurement of x-ray dielectric constants, or particle beam diagnostics. These issues will be discussed, and recent results will be presented

  1. Assessing the contribution of Centaur impacts to ice giant luminosities

    CERN Document Server

    Dodson-Robinson, Sarah E

    2015-01-01

    Voyager 2 observations revealed that the internal luminosity of Neptune is an order of magnitude higher than that of Uranus. If the two planets have similar interior structures and cooling histories, the luminosity of Neptune can only be explained by invoking some energy source beyond gravitational contraction. This paper investigates whether Centaur impacts could provide the energy necessary to produce the luminosity of Neptune. The major findings are (1) that impacts on both Uranus and Neptune are too infrequent to provide luminosities of order the observed value for Neptune, even for optimistic impact-rate estimates, and (2) that Uranus and Neptune rarely have significantly different impact-generated luminosities at any given time. Uranus and Neptune most likely have structural differences that force them to cool and contract at different rates.

  2. Assessing the contribution of centaur impacts to ice giant luminosities

    Science.gov (United States)

    Dodson-Robinson, Sarah E.

    2016-01-01

    Voyager 2 observations revealed that Neptune's internal luminosity is an order of magnitude higher than that of Uranus. If the two planets have similar interior structures and cooling histories, Neptune's luminosity can only be explained by invoking some energy source beyond gravitational contraction. This paper investigates whether centaur impacts could provide the energy necessary to produce Neptune's luminosity. The major findings are (1) that impacts on both Uranus and Neptune are too infrequent to provide luminosities of order Neptune's observed value, even for optimistic impact-rate estimates and (2) that Uranus and Neptune rarely have significantly different impact-generated luminosities at any given time. Uranus and Neptune most likely have structural differences that force them to cool and contract at different rates.

  3. Development of radiation protection and measurement technology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Si Young; Lee, T. Y.; Kim, J. L.; Kim, B. H.; Lee, B. J.; Chung, K. K.; Lee, K. C.; Chung, R. I.; Han, Y. D.; Kim, J. S.; Lee, H. S.; Kim, C. K.; Yoon, K. S.; Jeong, D. Y.; Yoon, S. C.; Yoon, Y. C.; Lee, S. Y.; Kim, J. S.; Seo, K. W. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kim, J. K.; Lee, J. K. [Hanyang Univ., Seoul (Korea, Republic of)

    1997-07-01

    Reference X-, gamma, beta and neutron radiation fields complying with the ISO and ANSI standards have been established and evaluated to provide a basic technical support in national radiation protection dosimetry program and to provide calibration measurement devices. Personal dose evaluation algorithm has been developed with these reference radiation fields, which comply well with both domestic and the new ANSI N13.11, to evaluate accurate personal dose equivalents. A personal internal dosimetry algorithm which can estimate the intakes of radionuclides from the results of in vivo bioassay and the resulting internal doses has been developed and verified its performance. It was also evaluated to be equality excellent compared with those being used in foreign countries and used to make a computer code for internal dose evaluation which can be run with PC under the Windows environment. A BOMAB phantom for precise calibration of in vivo system has been also designed, fabricated and test-evaluated. Based on the ALARA concept of the optimization principle of radiation protection, a method for estimating the cost for radiation protection has been studied and an objective monetary cost of detriment due to radiation exposure, called {alpha} value ($/man-Sv) has been derived and proposed based on the Korean socio-economic situation and human risk factors to provide basic data for the radiation protection optimization study in Korea. (author). 100 refs., 104 tabs., 69 figs.

  4. Development of radiation protection and measurement technology

    International Nuclear Information System (INIS)

    Reference X-, gamma, beta and neutron radiation fields complying with the ISO and ANSI standards have been established and evaluated to provide a basic technical support in national radiation protection dosimetry program and to provide calibration measurement devices. Personal dose evaluation algorithm has been developed with these reference radiation fields, which comply well with both domestic and the new ANSI N13.11, to evaluate accurate personal dose equivalents. A personal internal dosimetry algorithm which can estimate the intakes of radionuclides from the results of in vivo bioassay and the resulting internal doses has been developed and verified its performance. It was also evaluated to be equality excellent compared with those being used in foreign countries and used to make a computer code for internal dose evaluation which can be run with PC under the Windows environment. A BOMAB phantom for precise calibration of in vivo system has been also designed, fabricated and test-evaluated. Based on the ALARA concept of the optimization principle of radiation protection, a method for estimating the cost for radiation protection has been studied and an objective monetary cost of detriment due to radiation exposure, called α value ($/man-Sv) has been derived and proposed based on the Korean socio-economic situation and human risk factors to provide basic data for the radiation protection optimization study in Korea. (author). 100 refs., 104 tabs., 69 figs

  5. Measurement of Radiated Power Loss on EAST

    Institute of Scientific and Technical Information of China (English)

    段艳敏; 王亮; 胡立群; 毛松涛; 许平; 陈开云; 林士耀; 钟国强; 张继宗; 张凌

    2011-01-01

    A type of silicon detector known as AXUV (absolute extreme ultraviolet) photodiodes is successfully used to measure the radiated power in EAST. The detector is characterized by compact structure, fast temporal response (〈0.5 s) and flat spectral sensitivity in the range from ultra-violet to X-ray. Two 16-channel AXUV arrays are installed in EAST to view the whole poloidal cross-section of plasma. Based on the diagnostic system, typical radiation distributions for both limiter and divertor plasma are obtained and compared. As divertor detachment occurs, the radiation distribution in X-point region is observed to vary distinctly. The total radiation power losses in discharges with different plasma parameters are briefly analyzed.

  6. Aircrew radiation exposure: sources-risks-measurement

    International Nuclear Information System (INIS)

    A short review is given on the actual aircrew exposure and its sources. The resulting risks for harmful effects to the health and discuss methods for in-flight measurements of exposure is evaluated. An idea for a fairly simple and economic approach to a practical, airborne active dosimeter for the assessment of individual crew exposure is presented. The exposure of civil aircrew to cosmic radiation, should not be considered a tremendous risk to the health, there is no reason for panic. However, being significantly higher than the average exposure to radiation workers, it can certainly not be neglected. As recommended by ICRP, aircrew exposure has to be considered occupational radiation exposure and aircrews are certainly entitled to the same degree of protection, as other ground-based radiation workers have obtained by law, since long time. (author)

  7. Radiation measurements aboard the fourth Gemini flight.

    Science.gov (United States)

    Janni, J F; Schneider, M F

    1967-01-01

    Two special tissue-equivalent ionization chambers and 5 highly sensitive passive dosimetry packages were flown aboard the recent Gemini 4 flight for the purpose of obtaining precise values of instantaneous dose rate, accumulated dose. and shielding effectiveness. This experiment marked the first time that well-defined tissue dose and radiation survey measurements have been carried out in manned spaceflight operations. Since all measurements were accomplished under normal spacecraft environmental conditions, the biological dose resulted primarily from trapped inner Van Allen Belt radiation encountered by the spacecraft in the South Atlantic Anomaly. The experiment determined the particle type, ionizing and penetrating power, and variation with time and position within the Gemini spacecraft. Measured dose rates ranged from 100 mrad/hr for passes penetrating deeply into the South Atlantic Anomaly to less than 0.1 mrad/hr from lower latitude cosmic radiation. The accumulated tissue dose measured by the active ionization chambers, shielded by 0.4 gm/cm2 for the 4-day mission, was 82 mrad. Since the 5 passive dosimetry packages were each located in different positions within the spacecraft, the total mission surface dose measured by these detectors varied from 73 to 27 mrad, depending upon location and shielding. The particles within the spacecraft were recorded in nuclear emulsion, which established that over 90% of the tissue dose was attributable to penetrating protons. This experiment indicates that the radiation environment under shielded conditions at Gemini altitudes was not hazardous. PMID:11973852

  8. Size determination of the Centaur Chariklo from millimeter-wavelength bolometer observations

    OpenAIRE

    Altenhoff, W.J.; Menten, K. M.; Bertoldi, F.

    2000-01-01

    Using the Max-Planck Millimeter Bolometer Array (MAMBO) at the IRAM 30m telescope we detected emission at 250 GHz from the Centaur Chariklo (1997 CU26). The observed continuum flux density implies a photometric diameter of 273 km. The resulting geometric albedo is 0.055, somewhat higher than expected from a comparison with most of the other few Centaurs and cometary nuclei for which such data are available.

  9. Neutron measuring instruments for radiation protection

    International Nuclear Information System (INIS)

    The present report deals with selected topics from the field of neutron dosimetry for radiation protection connected with the work of the subcommittee 6802 in the Standards Committee on Radiology (NAR) of the German Standards Institute (DIN). It is a sort of material collection. The topics are: 1. Measurement of the absorbed-energy dose by a) ionization chambers in fields of mixed radiation and b) recoil-proton proportional counting tubes. 2. Measurement of the equivalent dose, neutron monitors, combination methods by a) rem-meters, b) recoil-proton counting tubes, c) recombination method, tissue-equivalent proportional counters, activation methods for high energies in fields of mixed radiation, d) personnel dosimetry by means of ionization chambers and counting tubes, e) dosimetry by means of activation methods, nuclear track films, nonphotographic nuclear track detectors and solid-state dosimeters. (orig./HP)

  10. Automatic radiation measuring system connected with GPS

    International Nuclear Information System (INIS)

    The most serious nuclear disaster in Japan has broken out at Fukushima Daiichi Nuclear Power Plant due to Great East Japan Earthquake. Prompt and exact mapping of the contamination is of great importance for radiation protection and for the environment restoration. We have developed radiation survey systems KURAMA and KURAMA-2 for rapid and exact measurement of radiation dose distribution. The system is composed of a mobile radiation monitor and the computer in office which is for the storage and visualization of the data. They are connected with internet and are operated for continuous radiation measurement while the monitor is moving. The mobile part consists of a survey meter, an interface to transform the output of the survey meter for the computer, a global positioning system, a computer to process the data for connecting to the network, and a mobile router. Thus they are effective for rapid mapping of the surface contamination. The operation and the performance of the equipment at the site are presented. (J.P.N.)

  11. Web based Measurement System for Solar Radiation

    Directory of Open Access Journals (Sweden)

    Shachi Awasthi

    2012-06-01

    Full Text Available We present in this paper, the principles of the measurement system for solar radiation, and our implementation using Web based data logging concept. The photocurrent produced by Silicon PN junction is used as a solar radiation transducer, to make it more viable we have used commercially available solar panels as our transducers. Using a silicon solar cell as sensor, a low cost solar radiometer can be constructed. The photocurrent produced by solar cell is electronically tailored to be measured and stored by our web based data acquisition and monitoring system. Measurement using real solar cell array gives a good measure of actual producible energy by solar arrays. Our portable instrument can be used in remote sites and substitutes the solar monitor and integrator, Current data of solar radiation can be monitored using Ethernet interface available in all PC, Laptops. We store the data into a secure digital card which can be retrieved to plot and analyse the data. We have developed system hardware and software based on ATmega32 AVR Microcontrollers and ENC28J60 Ethernet PHY and MAC network interface chip by Microchip. So the global irradiance data are obtained after correction using the instantaneous measurement of ambient temperature which allows us to calculate the junction temperature and consequently improve the precision of measurement of our data acquisition system.

  12. The measurement of solar ultraviolet radiation.

    Science.gov (United States)

    Roy, C R; Gies, H P; Lugg, D J; Toomey, S; Tomlinson, D W

    1998-11-01

    High skin cancer rates, stratospheric ozone depletion and increased public interest and concern have resulted in a strong demand for solar ultraviolet radiation measurements and information. The Australian Radiation Laboratory (ARL) has been involved since the mid-1980s in the measurement of solar ultraviolet radiation (UVR) using spectroradiometers (SRM) and a network of broadband detectors at 18 sites in Australia and Antarctica and in Singapore through a collaborative agreement with the Singapore Institute of Science and Forensic Medicine. Measurement locations range from equatorial (Singapore, 1.3 degrees N) through tropical (Darwin, 12.4 degrees S) to polar (Mawson, 67.6 degrees S) and as a result there are many difficulties associated with maintenance and calibration of the network detectors, and transfer of data to ensure an accurate and reliable data collection. Calibration procedures for the various detectors involve the comparison with simultaneous spectral measurements using a portable SRM incorporating a double monochromator, calibrated against traceable standard lamps. Laboratory measurements of cosine response and responsivity are also made. Detectors are intercompared at the Yallambie site for a number of months before installation at another location. As an additional check on the calibrations, computer models of solar UVR at the earth's surface for days with clear sky and known ozone are compared with the UV radiometer measurements. PMID:9920423

  13. Silica aerogel radiators for bunch length measurements

    International Nuclear Information System (INIS)

    Cherenkov radiators based on silica aerogel are used to measure the electron bunch length at the photo injector test facility at DESY Zeuthen (PITZ). The energy range of those electrons is 4-5 MeV. In this paper, the time resolution defined by the usage of aerogel is calculated analytically and Monte Carlo simulations are performed. It is shown that silica aerogel gives the possibility to reach a time resolution of about 0.1 ps for high photon intensities and a time resolution of about 0.02 ps can be obtained for thin silica aerogel radiators

  14. Deviating measurements in radiation protection. Legal assessment of deviations in radiation protection measurements

    International Nuclear Information System (INIS)

    This study investigates how, from a legal point of view, deviations in radiation protection measurements should be treated in comparisons between measured results and limits stipulated by nuclear legislation or goods transport regulations. A case-by-case distinction is proposed which is based on the legal concequences of the respective measurement. Commentaries on nuclear law contain no references to the legal assessment of deviating measurements in radiation protection. The examples quoted in legal commentaries on civil and criminal proceedings of the way in which errors made in measurements for speed control and determinations of the alcohol content in the blood are to be taken into account, and a commentary on ozone legislation, are examined for analogies with radiation protection measurements. Leading cases in the nuclear field are evaluated in the light of the requirements applying in case of deviations in measurements. The final section summarizes the most important findings and conclusions. (orig.)

  15. Statistics for Radiation Measurement. Chapter 5

    International Nuclear Information System (INIS)

    Measurement errors are of three general types: (i) blunders, (ii) systematic errors or accuracy of measurements, and (iii) random errors or precision of measurements. Blunders produce grossly inaccurate results and experienced observers easily detect their occurrence. Examples in radiation counting or measurements include the incorrect setting of the energy window, counting heavily contaminated samples, using contaminated detectors for imaging or counting, obtaining measurements of high activities, resulting in count rates that lead to excessive dead time effects, and selecting the wrong patient orientation during imaging. Although some blunders can be detected as outliers or by duplicate samples and measurements, blunders should be avoided by careful, meticulous and dedicated work. This is especially important where results will determine the diagnosis or treatment of patients

  16. A long term study of Centaur 174P/Echeclus

    Science.gov (United States)

    Rousselot, Philippe; Korsun, Pavlo; Kulyk, Irina; Petit, Jean-Marc; Guilbert-Lepoutre, Aurélie

    2015-11-01

    Centaur 174P/Echeclus was discovered by the Spacewatch program on March 3, 2000 and initially labelled (60558) 2000 EC 98 . On December 30, 2005, a surprising cometary outburst was discovered with the 5-m Mount Palomar Observatory telescope. This outburst corresponded to a change in the overall visual magnitude from about 21 to about 14. At that time (60558) 2000 EC 98 was located at 13.07 au to the Sun and was subsequently renamed with a cometary designation. This outburst lasted a few months and, one year later, no coma could be detected. Another secondary outburst happened in 2011 and lasted also a few months. This target was at its perihelion (5.82 au) on April 22, 2015.We present new observational data obtained with the 2.5-m Nordic Optical Telescope during the 2011 outburst and in July 2013, and with the robotic 2-m Liverpool telescope on April 27, 2014, August 13, 2014 and June 1, 2015. We also found archive observational data obtained on December 22, 2005.These archive images point out the extremely high level of the 174P/Echeclus activity during the first outburst. The R-magnitude and Afrho parameter of the target were estimated to 14.8 and 56000±3000 cm respectively. During the second outburst, in 2011, the activity level of the Centaur was lower, the R-Afrho parameters were 1200±100 cm and 480±70 cm in June and July respectively. The dust production rates needed to produce the observed comae were approximately 700 kg.s-1 in 2005 and between 10 and 20 kg.s-1 in 2011 assuming the average grain geometric albedo of 0.1 and low outflow velocities of the dust, less than 10 m.s-1. A possible scenario of the dust coma formation for the first outburst will also be proposed using a Monte Carlo modeling.Before the outburst the lightcurve amplitude was 0.24 magnitude in the R-band with a rotation period of 26.80 h (if a double-peaked lightcurve is assumed). The observational data obtained after the outburst with the NOT do not permit to detect any clear variation

  17. Automatic actinometric system for diffuse radiation measurement

    Science.gov (United States)

    Litwiniuk, Agnieszka; Zajkowski, Maciej

    2015-09-01

    Actinometric station is using for measuring solar of radiation. The results are helpful in determining the optimal position of solar panels relative to the Sun, especially in today's world, when the energy coming from the Sun and other alternative sources of energy become more and more popular. Polish climate does not provide as much energy as in countries in southern Europe, but it is possible to increase the amount of energy produced by appropriate arrangement of photovoltaic panels. There is the possibility of forecasting the amount of produced energy, the cost-effectiveness and profitability of photovoltaic installations. This implies considerable development opportunities for domestic photovoltaic power plants. This article presents description of actinometric system for diffuse radiation measurement, which is equipped with pyranometer - thermopile temperature sensor, amplifier AD620, AD Converter ADS1110, microcontroller Atmega 16, SD card, GPS module and LCD screen.

  18. Marine radiation measured with personal dosimeter

    International Nuclear Information System (INIS)

    This measurement was conducted after the Fukushima Daiichi Nuclear Power Plant Accident to study preliminarily the influence of the Accident on the sea water radiation and to get the information like materials and methods to measure the marine radiation for coming authorized study. The integrating dosimeters used were for personal fitting, Aloka's MYDOSEminiE PDM-111 with the silicon P-N junction semiconductor detector and ECOTEST's TERRA MKS-05, a GM tube type. Measurement was done with PDM-111 placed in a water-resistant vessel set up at 1 m and 3 cm distances from the bottom at the maximal depth of 100 m of 10 sea spots in Kochi Prefecture. Radiation doses were found to be 0.04-0.07 mcSv/h at the bottom of 6-13 m depth, which varied with the configuration of the bed, and 0.03 mcSv/h in water at either depth of the average 16 m or at 1 m far from the bottom. The dose rates in water and at bottom were found to decrease with increase of the depth by the enough long time measurement at 25 m and 40 m. Further, the more distant from the land, the lower the rates: 0.03-0.04 mcSv/h, which was thought to be derived from the cosmic ray. Results with MKS-05 were found to be of similar tendency to those by PDM-111 above and to be less sensitive. Authorized studies on marine radiation should be conducted systematically within a nearest future. (T.T.)

  19. Web based Measurement System for Solar Radiation

    Directory of Open Access Journals (Sweden)

    Shachi Awasthi

    2012-06-01

    Full Text Available We present in this paper, the principles of themeasurement system for solar radiation, and ourimplementation using Web based data loggingconcept.The photocurrent produced by Silicon PNjunction is used as a solar radiation transducer, tomake it more viable we have used commerciallyavailable solar panels as our transducers. Using asilicon solar cell as sensor, a low cost solarradiometer can be constructed. The photocurrentproduced by solar cell is electronically tailored to bemeasured and stored by our web based dataacquisition and monitoring system. Measurementusing real solar cell array gives a good measure ofactual producible energy by solar arrays. Ourportable instrument can be used in remote sites andsubstitutes the solar monitor and integrator,Current data of solar radiation can be monitoredusing Ethernet interface available in all PC,Laptops. We store the data into a secure digital cardwhich can be retrieved to plot and analyse the data.We have developed system hardware andsoftware based on ATmega32 AVR Microcontrollersand ENC28J60 Ethernet PHY and MAC networkinterface chip by Microchip.So the global irradiance data are obtained aftercorrection using the instantaneous measurement ofambient temperature which allows us to calculatethe junction temperature and consequently improvethe precision of measurement of our dataacquisition system

  20. First measurements of the Martian radiation environment

    International Nuclear Information System (INIS)

    The 2001 Mars Odyssey spacecraft has been returning data from Mars since February 2002. Its orbit is polar and nearly circular, about 400 km above the surface, with a two-hour period. Among the instruments onboard Odyssey are the Martian Radiation Environment Experiment (MARIE) and the Gamma Ray Spectrometer (GRS), which is a suite of instruments that includes several neutron detectors. This paper focuses on results from MARIE, which is measuring Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE) at Mars in order to assess radiation health risks to future human explorers. MARIE is highly efficient for SPE, and for GCR in the charge range from 2 (helium) to 10 (neon); spectra obtained in this range are compared to data from the ACE/ CRIS detector and show good agreement. The SPE data obtained by MARIE are unique and may show effects due to 'magnetic anomalies,' regions of remanent magnetism on the Martian surface. Data from the Mars Global Surveyor magnetometer are used in this analysis. Although the GRS instruments are primarily intended to measure radiation from the Martian surface, both the gamma-ray detector and the neutron detectors provide valuable information about the local radiation environment at Mars. The gamma-ray crystal is useful in providing coverage during MARIE data outages, which arise due to limited storage space and tend to limit acquisition during SPE. The neutron detectors provide data that can, with modeling of neutron transport through the atmosphere, be used to predict surface neutron doses. The combined data from these instruments are giving a clear picture of the radiation environment at Mars and the potential risks that will be faced by humans who venture there

  1. Radiation exposure measurement onboard civil aircraft

    International Nuclear Information System (INIS)

    The active dosemeter DOSTEL based on two silicon planar detectors was flown on civil aircraft flights to study the radiation exposure of air crew members. The altitude and latitude dependence of count and dose rates as well as long-term variations are measured. After calibration of the DOSTEL response against measurements of a TEPC instrument, total dose-equivalent values for various flights are compared with H*(10) calculations by EPCARD yielding a ratio of 1.02 ± 0.09 (standard variation). (authors)

  2. When Lulu met the Centaur: Photographic traces of creaturely love

    Directory of Open Access Journals (Sweden)

    Dominic Pettman

    2015-04-01

    Full Text Available The brief triangular love between Nietzche, Salomé, and Rée – as crystallised in the famous photograph of kitsch (literal horse-play, where the woman is depicted as treating the two men as beasts of burden – allows us to consider the role of ‘creaturely love’ in our more general understanding of the lover’s discourse. That is to say, through such images we can explore the role and figure of the animal within ‘the anthropological machine’, itself designed to produce a sense of the human from the inhuman (especially through mediated forms of intimacy. Further, in the different intermedial relationships between photography, poetry, and philosophy, the Centaur – in the letters and texts circulated by this group (later including Rilke – provides a charged specific totem for a libidinal ecology of souls, striving to understand themselves as simultaneously creaturely and spiritual. Such a figure allowed both a recognition and a disavowal of the nonhuman basis (and telos of human affections.

  3. Miniature detector measures deep space radiation

    Science.gov (United States)

    Schultz, Colin

    2011-08-01

    The 1972 journey of Apollo 17 marked not only the last time a human walked on the Moon but also the most recent manned venture beyond the outer reaches of the Earth's atmosphere. With preparations being made for humans to once again explore deep space, important steps are under way to quantify the hazards of leaving low-Earth orbit. One significant risk for long-distance missions is the increased exposure to ionizing radiation—energetic particles that can strip electrons off of otherwise neutral materials, affecting human health and the functioning of spacecraft equipment. The deep space probes that are being sent to measure the risks from ionizing radiation and other hazards can be costly, so maximizing the scientific value of each launch is important. With this goal in mind, Mazur et al. designed and developed a miniature dosimeter that was sent into lunar orbit aboard NASA's Lunar Reconnaissance Orbiter (LRO) in 2009. Weighing only 20 grams, the detector is able to measure fluctuations in ionizing radiation as low as 1 microrad (equivalent to 1.0 × 10-8 joules of energy deposited into 1 kilogram) while requiring minimal power and computer processing. The postage stamp-sized detector tracked radiation dosages for the first year of LRO's mission, with the results being confirmed by other onboard and near-Earth detectors. (Space Weather, doi:10.1029/2010SW000641, 2011)

  4. Physical properties of the extreme centaur and super-comet candidate 2013 AZ60

    CERN Document Server

    Pál, A; Horner, J; Szakáts, R; Vilenius, E; Müller, Th G; Acosta-Pulido, J; Licandro, J; Cabrera-Lavers, A; Sárneczky, K; Szabó, Gy M; Thirouin, A; Sipőcz, B; Dózsa, Á; Duffard, R

    2015-01-01

    We present estimates of the basic physical properties -- including size and albedo -- of the extreme Centaur 2013 AZ60. These properties have been derived from optical and thermal infrared measurements. Our optical measurements revealed a likely full period of ~9.4 h with a shallow amplitude of 4.5%. By combining optical brightness information and thermal emission data, we are able to derive a diameter of 62.3 +/- 5.3 km and a geometric albedo of 2.9% -- corresponding to an extremely dark surface. Additionally, our finding of ~> 50 Jm^{-2}K^{-1}s^{-1/2} for the thermal inertia is also noticeably for objects in such a distance. The results of dynamical simulations yield an unstable orbit, with a 50% probability that the target will be ejected from the Solar System within 700,000 years. The current orbit of this object as well as its instability could imply a pristine cometary surface. This possibility is in agreement with the observed low geometric albedo and red photometric colour indices for the object, whic...

  5. Reflections on Centaur Upper Stage Integration by the NASA Lewis (Glenn) Research Center

    Science.gov (United States)

    Graham, Scott R.

    2014-01-01

    The NASA Glenn (then Lewis) Research Center (GRC) led several expendable launch vehicle (ELV) projects from 1963 to 1998, most notably the Centaur upper stage. These major, comprehensive projects included system management, system development, integration (both payload and stage), and launch operations. The integration role that GRC pioneered was truly unique and highly successful. Its philosophy, scope, and content were not just invaluable to the missions and vehicles it supported, but also had significant Agencywide benefits. An overview of the NASA Lewis Research Center (now the NASA Glenn Research Center) philosophy on ELV integration is provided, focusing on Atlas/Centaur, Titan/Centaur, and Shuttle/Centaur vehicles and programs. The necessity of having a stable, highly technically competent in-house staff is discussed. Significant depth of technical penetration of contractor work is another critical component. Functioning as a cohesive team was more than a concept: GRC senior management, NASA Headquarters, contractors, payload users, and all staff worked together. The scope, content, and history of launch vehicle integration at GRC are broadly discussed. Payload integration is compared to stage development integration in terms of engineering and organization. Finally, the transition from buying launch vehicles to buying launch services is discussed, and thoughts on future possibilities of employing the successful GRC experience in integrating ELV systems like Centaur are explored.

  6. Measurement of Thermal Radiation Properties of Solids

    Science.gov (United States)

    Richmond, J. C. (Editor)

    1963-01-01

    The overall objectives of the Symposium were to afford (1) an opportunity for workers in the field to describe the equipment and procedures currently in use for measuring thermal radiation properties of solids, (2) an opportunity for constructive criticism of the material presented, and (3) an open forum for discussion of mutual problems. It was also the hope of the sponsors that the published proceedings of the Symposium would serve as a valuable reference on measurement techniques for evaluating thermal radiation properties of solids, partic.ularly for those with limited experience in the field. Because of the strong dependence of emitted flux upon temperature, the program committee thought it advisable to devote the first session to a discussion of the problems of temperature measurement. All of the papers in Session I were presented at the request of and upon topics suggested by the Committee. Because of time and space limitations, it, was impossible to consider all temperature measurement problems that might arise--the objective was rather to call to the attention of the reader some of the problems that might be encountered, and to provide references that might provide solutions.

  7. Photocatalytic Active Radiation Measurements and Use

    Science.gov (United States)

    Davis, Bruce A.; Underwood, Lauren W.

    2011-01-01

    Photocatalytic materials are being used to purify air, to kill microbes, and to keep surfaces clean. A wide variety of materials are being developed, many of which have different abilities to absorb various wavelengths of light. Material variability, combined with both spectral illumination intensity and spectral distribution variability, will produce a wide range of performance results. The proposed technology estimates photocatalytic active radiation (PcAR), a unit of radiation that normalizes the amount of light based on its spectral distribution and on the ability of the material to absorb that radiation. Photocatalytic reactions depend upon the number of electron-hole pairs generated at the photocatalytic surface. The number of electron-hole pairs produced depends on the number of photons per unit area per second striking the surface that can be absorbed and whose energy exceeds the bandgap of the photocatalytic material. A convenient parameter to describe the number of useful photons is the number of moles of photons striking the surface per unit area per second. The unit of micro-einsteins (or micromoles) of photons per m2 per sec is commonly used for photochemical and photoelectric-like phenomena. This type of parameter is used in photochemistry, such as in the conversion of light energy for photosynthesis. Photosynthetic response correlates with the number of photons rather than by energy because, in this photochemical process, each molecule is activated by the absorption of one photon. In photosynthesis, the number of photons absorbed in the 400 700 nm spectral range is estimated and is referred to as photosynthetic active radiation (PAR). PAR is defined in terms of the photosynthetic photon flux density measured in micro-einsteins of photons per m2 per sec. PcAR is an equivalent, similarly modeled parameter that has been defined for the photocatalytic processes. Two methods to measure the PcAR level are being proposed. In the first method, a calibrated

  8. Autonomous rendezvous and docking operations of unmanned expendable cargo transfer vehicles (e.g. Centaur) with Space Station Freedom

    Science.gov (United States)

    Emmet, Brian R.

    1991-01-01

    This paper describes the results of the feasibility study using Centaur or other CTV's to deliver payloads to the Space Station Freedom (SSF). During this study was examined the requirements upon unmanned cargo transfer stages (including Centaur) for phasing, rendezvous, proximity operations and docking/berthing (capture).

  9. Radiation measurement on the International Space Station

    Energy Technology Data Exchange (ETDEWEB)

    Akopova, A.B. [Yerevan Physics Institute, 2Alikhanyan Brs str, YerPhI, Yerevan (Armenia)]. E-mail: akopova@lx2.yerphi.am; Manaseryan, M.M. [Yerevan Physics Institute, 2Alikhanyan Brs str, YerPhI, Yerevan (Armenia); Melkonyan, A.A. [Yerevan Physics Institute, 2Alikhanyan Brs str, YerPhI, Yerevan (Armenia); Tatikyan, S.Sh. [Yerevan Physics Institute, 2Alikhanyan Brs str, YerPhI, Yerevan (Armenia); Potapov, Yu. [Research Center of Spacecraft Radiation Safety, Moscow (Russian Federation)

    2005-02-01

    The results of an investigation of radiation environment on board the ISS with apogee/perigee of 420/380km and inclination 51.6{sup o} are presented. For measurement of important characteristics of cosmic rays (particles fluxes, LET spectrum, equivalent doses and heavy ions with Z>=2) a nuclear photographic emulsion as a controllable threshold detector was used. The use of this detector permits a registration of the LET spectrum of charged particles within wide range of dE/dx and during last years it has already been successfully used on board the MIR station, Space Shuttles and 'Kosmos' spacecrafts. An integral LET spectrum was measured in the range 0.5-2.2x103keV/{mu}m and the value of equivalent dose 360{mu}Sv/day was estimated. The flux of biologically dangerous heavy particles with Z>=2 was measured (3.85x103particles/cm2)

  10. Radiated BPF sound measurement of centrifugal compressor

    International Nuclear Information System (INIS)

    A technique to measure radiated BPF sound from an automotive turbocharger compressor impeller is proposed in this paper. Where there are high-level background noises in the measurement environment, it is difficult to discriminate the target component from the background. Since the effort of measuring BPF sound was taken in a room with such condition in this study, no discrete BPF peak was initially found on the sound spectrum. Taking its directionality into consideration, a microphone covered with a parabolic cone was selected and using this technique, the discrete peak of BPF was clearly observed. Since the level of measured sound was amplified due to the area-integration effect, correction was needed to obtain the real level. To do so, sound measurements with and without a parabolic cone were conducted for the fixed source and their level differences were used as correction factors. Consideration is given to the sound propagation mechanism utilizing measured BPF as well as the result of a simple model experiment. The present method is generally applicable to sound measurements conducted with a high level of background noise

  11. Radiated BPF sound measurement of centrifugal compressor

    Science.gov (United States)

    Ohuchida, S.; Tanaka, K.

    2013-12-01

    A technique to measure radiated BPF sound from an automotive turbocharger compressor impeller is proposed in this paper. Where there are high-level background noises in the measurement environment, it is difficult to discriminate the target component from the background. Since the effort of measuring BPF sound was taken in a room with such condition in this study, no discrete BPF peak was initially found on the sound spectrum. Taking its directionality into consideration, a microphone covered with a parabolic cone was selected and using this technique, the discrete peak of BPF was clearly observed. Since the level of measured sound was amplified due to the area-integration effect, correction was needed to obtain the real level. To do so, sound measurements with and without a parabolic cone were conducted for the fixed source and their level differences were used as correction factors. Consideration is given to the sound propagation mechanism utilizing measured BPF as well as the result of a simple model experiment. The present method is generally applicable to sound measurements conducted with a high level of background noise.

  12. Measuring concentrations of elements using neutron radiation

    International Nuclear Information System (INIS)

    An apparatus for measuring the concentrations of elements in a material by the capture gamma method is claimed. The apparatus comprises either an isotope source or a neutron generator as the neutron source, a semi-conductor detector as the gamma-radiation detector, and a moderator which is, at least in part, heavy water. The detector is adapted to be placed adjacent to or inside a specimen in the flux of slow neutrons so that sufficient moderator is disposed between the source and the sample-detector combination that only relatively few fast neutrons will reach the detector

  13. Fundamentals of radiation protection measuring technique

    International Nuclear Information System (INIS)

    Stationary radiation protection measuring systems (local dose rate systems) are widely distributed. Since January 1sup(st), 1983 a number of these systems must be calibrated by a gauging office if they are used on the basis of legal regulations. The design type requirements made by the PTB in connection with the calibration duty as well as the transitional regulations for local dose rate systems already in operation have been prepared by a working committee including members of users, suppliers, gange supervising authorities, Technische Ueberwachungs-Vereine and the PTB. (orig./DG)

  14. The evolution of computer monitoring of real time data during the Atlas Centaur launch countdown

    Science.gov (United States)

    Thomas, W. F.

    1981-01-01

    In the last decade, improvements in computer technology have provided new 'tools' for controlling and monitoring critical missile systems. In this connection, computers have gradually taken a large role in monitoring all flights and ground systems on the Atlas Centaur. The wide body Centaur which will be launched in the Space Shuttle Cargo Bay will use computers to an even greater extent. It is planned to use the wide body Centaur to boost the Galileo spacecraft toward Jupiter in 1985. The critical systems which must be monitored prior to liftoff are examined. Computers have now been programmed to monitor all critical parameters continuously. At this time, there are two separate computer systems used to monitor these parameters.

  15. Radiative lifetime measurements of rubidium Rydberg states

    International Nuclear Information System (INIS)

    We have measured the radiative lifetimes of ns, np and nd Rydberg states of rubidium in the range 28 ≤ n ≤ 45. To enable long-lived states to be measured, our experiment uses slow-moving (∼100 μK) 85Rb atoms in a magneto-optical trap (MOT). Two experimental techniques have been adopted to reduce random and systematic errors. First, a narrow-bandwidth pulsed laser is used to excite the target nl Rydberg state, resulting in minimal shot-to-shot variation in the initial state population. Second, we monitor the target state population as a function of time delay from the laser pulse using a short-duration, millimetre-wave pulse that is resonant with a one- or two-photon transition to a higher energy 'monitor state', n'l'. We then selectively field ionize the monitor state, and detect the resulting electrons with a micro-channel plate. This signal is an accurate mirror of the nl target state population, and is uncontaminated by contributions from other states which are populated by black body radiation. Our results are generally consistent with other recent experimental results obtained using a method which is more prone to systematic error, and are also in excellent agreement with theory.

  16. SUMER: Solar Ultraviolet Measurements of Emitted Radiation

    Science.gov (United States)

    Wilhelm, K.; Axford, W. I.; Curdt, W.; Gabriel, A. H.; Grewing, M.; Huber, M. C. E.; Jordan, S. D.; Kuehne, M.; Lemaire, P.; Marsch, E.

    1992-01-01

    The experiment Solar Ultraviolet Measurements of Emitted Radiation (SUMER) is designed for the investigations of plasma flow characteristics, turbulence and wave motions, plasma densities and temperatures, structures and events associated with solar magnetic activity in the chromosphere, the transition zone and the corona. Specifically, SUMER will measure profiles and intensities of Extreme Ultraviolet (EUV) lines emitted in the solar atmosphere ranging from the upper chromosphere to the lower corona; determine line broadenings, spectral positions and Doppler shifts with high accuracy, provide stigmatic images of selected areas of the Sun in the EUV with high spatial, temporal and spectral resolution and obtain full images of the Sun and the inner corona in selectable EUV lines, corresponding to a temperature from 10,000 to more than 1,800,000 K.

  17. About Solar Radiation Intensity Measurements and Data Processing

    OpenAIRE

    MICH-VANCEA Claudiu; GORDAN Ioan Mircea

    2012-01-01

    Measuring the intensity of solar radiation is one of the directions of investigation necessary for the implementation of photovoltaic systems in a particular geographical area. This can be done by using specific measuring equipment (pyranometer) sensors based onthermal or photovoltaic principle. In this paper it is presented a method for measuring solar radiation (which has two main components - direct radiation and diffuse radiation) with sensors based on photovoltaic principle. Such data ar...

  18. Radiation damage measurements in room-temperature semiconductor radiation detectors

    CERN Document Server

    Franks, L A; Olsen, R W; Walsh, D S; Vizkelethy, G; Trombka, J I; Doyle, B L; James, R B

    1999-01-01

    The literature of radiation damage measurements on cadmium zinc telluride (CZT), cadmium telluride (CT), and mercuric iodide (HgI sub 2) is reviewed and in the case of CZT supplemented by new alpha particle data. CZT strip detectors exposed to intermediate energy (1.3 MeV) proton fluences exhibit increased interstrip leakage after 10 sup 1 sup 0 p/cm sup 2 and significant bulk leakage after 10 sup 1 sup 2 p/cm sup 2. CZT exposed to 200 MeV protons shows a two-fold loss in energy resolution after a fluence of 5x10 sup 9 p/cm sup 2 in thick (3 mm) planar devices but little effect in 2 mm devices. No energy resolution effects were noted from a moderated fission spectrum of neutrons after fluences up to 10 sup 1 sup 0 n/cm sup 2 , although activation was evident. Exposures of CZT to 5 MeV alpha particles at fluences up to 1.5x10 sup 1 sup 0 alpha/cm sup 2 produced a near linear decrease in peak position with fluence and increases in FWHM beginning at about 7.5x10 sup 9 alpha/cm sup 2. CT detectors show resolution...

  19. Cosmic Radiation Measurements in Airline Service

    International Nuclear Information System (INIS)

    Ionising radiation monitoring equipment is installed in all Concordes and much data have been derived. To validate the measurements from the on-board monitoring equipment, a programme of measurements on Concorde has been carried out using passive dosemeters in association with the UK National Radiological Protection Board. Data from a typical month (in this case October 1997) shows an arithmetic mean dose across the British Airways Concorde fleet of 12.9 (±0.4) μSv.h-1. Results from the NRPB measurements for the same month give a dose of 11.4 (±0.5) μSv.h-1 and application of the CARI 3Q programme gives a dose of 9.6 μSv.h-1 for the same month. The effective route dose between London and New York gives a mean value of 43.1 μSv for the Concorde detectors. The NRPB results give a route dose of 38.9 μSv whereas the CARI 3Q programme gives a route dose of 32.5 μSv. Measurements have also been performed on the Boeing 747-400 aircraft on the high latitude ultralonghaul direct London-Tokyo flight and these give values in the region of 6 μSv.h-1, against the CARI 3Q estimate of 3.7 μSv.h-1. (author)

  20. On measures to reduce anxiety of radiation

    International Nuclear Information System (INIS)

    Comparisons with other risks help to put radiation risk into perspective and facilitate communication of radiation risk to the public. More information and communication on radiation, clear behavioural guidelines in situations of increased radiation levels, and respect for citizens' concerns about radiation protection would counterbalance the publics fears and feelings of vulnerability. The use of the term radiophobia is discouraged as a description of public concerns. It is recommended that persons who appear unduly fearful of radiation should be handled with care and given professional medical treatment

  1. Radiation measurements on the ''Kosmos-900'' satellite

    International Nuclear Information System (INIS)

    Considered is the design and principle of operation of differential electron spectrometers positioned on the ''Kosmos-900'' satellite. Spectrometers are intended for detection of electron of the energy from 30 to 1600 keV with the help of semiconductor diffusion-drift silicon detectors placed in bending magnet systems with angular deviation of 180 deg. Presented are preliminary results of measuring electron fluxes on the ''Kosmos'-900'' satellite orbit. Spectrometer channel calibration has been made with the help of electron and γ sources. The results of determination of spectrometer efficiency are presented. Presented also are the differential energy spectra of electrons obtained in radiation Earth belt in magnetically calm period of 7.06 1977, 03sup(n)59sup(m)-04sup(n)0Ssup(m)

  2. SUMER: Solar Ultraviolet Measurements of Emitted Radiation

    Science.gov (United States)

    Wilhelm, K.; Axford, W. I.; Curdt, W.; Gabriel, A. H.; Grewing, M.; Huber, M. C. E.; Jordan, M. C. E.; Lemaire, P.; Marsch, E.; Poland, A. I.

    1988-01-01

    The SUMER (solar ultraviolet measurements of emitted radiation) experiment is described. It will study flows, turbulent motions, waves, temperatures and densities of the plasma in the upper atmosphere of the Sun. Structures and events associated with solar magnetic activity will be observed on various spatial and temporal scales. This will contribute to the understanding of coronal heating processes and the solar wind expansion. The instrument will take images of the Sun in EUV (extreme ultra violet) light with high resolution in space, wavelength and time. The spatial resolution and spectral resolving power of the instrument are described. Spectral shifts can be determined with subpixel accuracy. The wavelength range extends from 500 to 1600 angstroms. The integration time can be as short as one second. Line profiles, shifts and broadenings are studied. Ratios of temperature and density sensitive EUV emission lines are established.

  3. Alpha radiation measurement - Recommendations dossier for measurements optimization

    International Nuclear Information System (INIS)

    Used in the medical domain, in the military industry or in the electronuclear industry, the alpha radiation, by its detection and measurement, is of prime importance for the environmental control, the follow up of any industrial technical operation or the measurement of the health impact of radioactivity. This book gathers the basic knowledge, both practical and theoretical, and the necessary recommendations that any operator, technician or engineer would need to know for the use of alpha spectroscopy as a quantitative and qualitative method of analysis. It supplies information in the domains of: - sources preparation for alpha spectroscopy measurement; - measurements implementation for each technique: proportional counter, semiconductor alpha spectroscopy, grid chamber and liquid scintillation; - results processing and display; - quality assurance. It makes a synthesis of the know-how of laboratories in the fabrication of thin sources by supplying simple but important rules as well as information allowing to deal with the physical and chemical limits of thin sources. It lists the techniques relative to alpha particles detection and describes for each of them their sensitivity, advantages and drawbacks, and field of use. It introduces in the simplest as possible manner the mathematical tools needed for spectra deconvolution with some practical examples allowing to illustrate some complex situations encountered. It supplies to the user the theoretical and practical background necessary for the production of reliable and valid results. Finally, it includes and discusses the recent considerations about the calculation of decision threshold and detection limits. Content: 1 - reference documents: scientific and technical documents, standards, nuclear data; 2 - natural and artificial alpha radioactivity: discovery of alpha radiation, natural alpha radioactivity, artificial alpha radioactivity (medical, industrial exposure), dating method using nuclear phenomena; 3

  4. Radiation measurement on the International Space Station.

    Science.gov (United States)

    Akopova, A B; Manaseryan, M M; Melkonyan, A A; Tatikyan, S Sh; Potapov, Yu

    2005-02-01

    The results of an investigation of radiation environment on board the ISS with apogee/perigee of 420/380 km and inclination 51.6 degrees are presented. For measurement of important characteristics of cosmic rays (particles fluxes, LET spectrum, equivalent doses and heavy ions with Z > or = 2) a nuclear photographic emulsion as a controllable threshold detector was used. The use of this detector permits a registration of the LET spectrum of charged particles within wide range of dE/dx and during the last years it has already been successfully used on board the MIR station, Space Shuttles and "Kosmos" spacecrafts. An integral LET spectrum was measured in the range 0.5-2.2 x 10(3) keV/micrometers and the value of equivalent dose 360 microSv/day was estimated. The flux of biologically dangerous heavy particles with Z > or = 2 was measured (3.85 x 10(3) particles/cm2). PMID:15856556

  5. TNOs are Cool: A Survey of the Transneptunian Region: A Herschel-PACSview of 16 Centaurs

    CERN Document Server

    Duffard, R; Santos-Sanz, P; Vilenius, E; Ortiz, J L; Mueller, Th; Fornasier, S; Lellouch, E; Mommert, M; Pal, A; Kiss, C; Mueller, M; Stansberry, J; Delsanti, A; Peixinho, N; Trilling, D

    2013-01-01

    The goal of this work is to characterize a set of 16 Centaurs in terms of their size, albedo, and thermal properties. We study the correlations for a more extended sample, obtained from the literature, of diameter, albedo, orbital parameters and spectral slopes. We have done three-band photometric observations using Herschel/PACS and we use a consistent method for data reduction and aperture photometry of this sample to obtain monochromatic flux densities at 70, 100 and 160 $\\mu$m. Additionally, we use Spitzer/MIPS flux densities at 24 and 70 $\\mu$m when available. We also include the Centaurs sample observed only with Spitzer/MIPS and Scattered Disk Objects, a dynamical family of TNOs, presented in a previous work of the team. We have determined new radiometric sizes and albedos of 16 Centaurs. The first conclusion is that the albedo of the Centaurs is not determined by their orbit. Similarly we do not find any correlation between diameter and orbital parameters. We also find that most of the objects in our ...

  6. VizieR Online Data Catalog: Observations of 50 TNOs and Centaurs (Desmars+, 2015)

    Science.gov (United States)

    Desmars, J.; Camargo, J. I. B.; Braga-Ribas, F.; Vieira-Martins, R.; Assafin, M.; Vachier, F.; Colas, F.; Ortiz, J. L.; Duffard, R.; Morales, N.; Sicardy, B.; Gomes-Junior, A. R.; Benedetti-Rossi, G.

    2015-10-01

    The table provides 2895 ground-based observations of 50 trans-Neptunian objects and Centaurs performed between 2007 and 2014. The table contains the name of the observed TNO, the date of the observation, the topocentric ICRS coordinates of the object and the IAU observatory code. (1 data file).

  7. Ground truth data for test sites (SL-3). [solar radiation and thermal radiation brightness temperature measurements

    Science.gov (United States)

    1974-01-01

    Field measurements performed simultaneously with Skylab overpasses in order to provide comparative calibration and performance evaluation measurements for the EREP sensors are presented. The solar radiation region from 400 to 1300 nanometers and the thermal radiation region from 8 to 14 micrometer region were investigated. The measurements of direct solar radiation were analyzed for atmospheric optical depth; the total and reflected solar radiation were analyzed for target reflectivity. These analyses were used in conjunction with a radiative transfer computer program in order to calculate the amount and spectral distribution of solar radiation at the apertures of the EREP sensors. The instrumentation and techniques employed, calibrations and analyses performed, and results obtained are discussed.

  8. Microdosimetric measurements for radiotherapy and radiation protection

    International Nuclear Information System (INIS)

    Neutrons produced by bombarding a 4 mm thick beryllium target with deuterons of 30 MeV and 70 MeV proton beams are used for a clinical trials of radiotherapy in NIRS cyclotron facility. Microdosimetric measurements for neutrons and protons were carried out using a tissue-equivalent (TE) proportional counters, and LET-1/2-SW counter and LET-5-SW counter. The TE gas employed is the propane based mixture, and pressure of 67.7 torr provided an effective sphere diameter of 2 μm for LET-1/2-SW counter. Alpha particles emitted from Cm-244 have an energy of approximatey 5.8 MeV, and the energy loss in a 2 μm path length of propane based TE gas was calculated to be 79.2 keV/μm. For the improvement of S/N ratio, a probetype charge sensitive pre-amplifier built in a first stage FET was used. Electronic signals were amplified and processed with a homemade spectroscopy logarithmic amplifier and a multichannel analyzer. The logarithmic amplifier made it possible to measure the dose distributions in lineal energy from less than 50 eV/μm to 2000 keV/μm at the same time. The number of pulse as a function of lineal energy in logarithm was stored and then processed with a personal computer (PC-9801). The measurement were also made on mixed radiation fields of neutron and proton and gamma-rays in order to investigate the variation of dose distribution in lineal energy. The differential distribution of dose in lineal energy, d(y) = y·n(y) was normalized to yield the fraction of dose deposited per unit of lineal energy. On the basis of these distributions, the dose-averaged LET and the average quality factor for radiations outside the primary beams was determined by using calculated with separately d(y)-distribution of a Photon fields. (author)

  9. Gamma radiation measurements in Brazilian commercial granites

    International Nuclear Information System (INIS)

    Full text of publication follows: Gamma radiation from radionuclides which are characterized by half lives comparable to the age of the earth, such as 40 K and the radionuclides from the 238 U and 232 Th series, and their decay products, represent the main terrestrial source of irradiation to the human body. Their concentrations vary for different types of rocks, where high radiation levels are associated with igneous rocks such as granite. Thorium, uranium and potassium concentrations of granitic rocks are intimately related to their mineral compositions and general petrologic features. Then, these features associated with effects of weathering and metamorphism produce expressive alterations in the relationship between the natural radionuclides (Th, U, K, Th/U and Th/K). Consequently, the measurements of thorium, uranium, and potassium concentrations of different granite samples result on individual differentiation sequences. From the 232 Th, 238 U and 40 K activity concentrations obtained for each sample, it is possible to evaluate their respective dose rates in air, when these stones are used as tiling rocks. These results are of great interest in the environmental radiological protection study, since granites are widely used as building and ornamental materials, including as indoor covering. In this way, the Laboratory of Radioecology (L.A.R.A.) of the Physics Institute of the Universidade Federal Fluminense (I.F. -U.F.F.) has been performing analyzes on more than one hundred differ ent types of the main Brazilian commercial granites in last two years [1]. Using NaI and HP Ge gamma-ray spectrometers to determine the concentration of natural radionuclides in these samples, the annual effective dose rates and the gamma activity concentration index have been evaluated and compared to the limits proposed by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and European Commission (E.C.). In addition, the correlations between thorium

  10. Radiation detection and measurement concepts, methods and devices

    CERN Document Server

    McGregor, Douglas

    2017-01-01

    This text on radiation detection and measurement is a response to numerous requests expressed by students at various universities, in which the most popularly used books do not provide adequate background material, nor explain matters in understandable terms. This work provides a modern overview of radiation detection devices and radiation measurement methods. The topics selected in the book have been selected on the basis of the author’s many years of experience designing radiation detectors and teaching radiation detection and measurement in a classroom environment.

  11. Radiation power measurement on the ADITYA tokamak

    Science.gov (United States)

    Tahiliani, Kumudni; Jha, Ratneshwar; Gopalkrishana, M. V.; Doshi, Kalpesh; Rathod, Vipal; Hansalia, Chandresh; ADITYA Team

    2009-08-01

    The radiation power loss and its variation with plasma density and current are studied in the ADITYA tokamak. The radiation power loss varies from 20% to 40% of the input power for different discharges. The radiation fraction decreases with increasing plasma current but it increases with increasing line-averaged central density. The radiated power behavior has also been studied in discharges with short pulses of molecular beam injection (MBI) and gas puff (GP). The increase in radiation loss is limited to the edge chords in the case of GP, but it extends to the core region for MBI fueling. The MBI seems to indicate reduction in the edge recycling. It is observed that during the density limit disruption, the radiated power loss is more in the current quench phase as compared with the thermal quench phase and comes mainly from the plasma edge.

  12. Electromagnetically driven radiative shocks and their measurements

    International Nuclear Information System (INIS)

    Experimental results on a generation of strong shocks in a compact pulse power device are reported. The characteristics of strong shocks are different from hydrodynamical shocks' because they depend on not only collisions but radiation processes. Radiative shocks are relevant to high energy density phenomena such as the explosions of supernovae. When initial pressure is lower than about 50 mtorr, an interesting structure is confirmed at the shock front, which might indicate a phenomenon proceeded by the radiative process. (author)

  13. New standards for ionizing radiation measurements

    International Nuclear Information System (INIS)

    The Ionizing Radiation Division has developed new national standards for mammographic X rays and for brachytherapy sources, such as iodine-125. The Attix chamber, a variable volume free-air ionization chamber, has been established as the primary national standard for mammographic X rays. The Attix chamber resides in the newly developed NIST Mammography Calibration Range and will be used to perform routine calibrations. The wide-angle free-air ionization chamber utilizes a large volume and a novel electric field configuration in order to circumvent the limitations of conventional free-air chambers. Seventeen beam qualities for X rays from molybdenum (Mo) and rhodium (Rh) anodes have been parameterized for the calibration of mammographic ionization chambers. The beam qualities available include anode/filter combinations of Mo/Mo, Mo/Rh and Rh/Rh. The mammography range was developed in collaborations with the U.S. Food and Drug Administration's (FDA) Center for Devices and Radiological Health, the implementors of the Mammography Quality Standards Act (MQSA) of 1992. The wide-angle free-air ionization chamber has been used to measure the output of two types of iodine-125 seeds, those with resin balls and those with silver wire. Both free-air chambers have been intercompared with the Ritz parallel-plate free-air ionization chamber

  14. Radiation measurements on the ''Kosmos-900'' satellite

    International Nuclear Information System (INIS)

    Presented are the experiment description and preliminary results of measuring the differential proton spectra in the energy range from 30 keV up to 30 MeV in the Earth radiation belts performed on the ''Kosmos-900'' satellite. According to the data obtained in the morning sector of magnetosphere a comparative analysis of differential proton spectra is carried out in the magnetically calm period of large duration and during magnetic agitation. In the range of Mc Ilvine parameter L approximately 3-5 differential proton spectra have maximum at the energy Ep approximately 100-300 keV. Maximum values Esub(max)(L) are higher in magnetically calm period than during magnetic agitation. This difference increases at L decrease, reaches the largest value on L=4 and decreases at further decrease of α. In the depth of plasmosphere (L approximately 3). Esub(max)(L) positions coincide in magnetically calm period and during magnetic agitation. A relation between Esub(max)(L) position in differential proton spectra and the average space distribution of cold plasma is traced

  15. Molecular radiation - Its application in physical measurements and analyses

    Science.gov (United States)

    1969-01-01

    Specialists Conference held at Marshall Space Flight Center reviewed work in molecular radiation to evaluate research possibilities in this field. Topics included spectral-line studies in the labortory, application to practical heat transfer calculations of radiative transfer models, and use of measured radiation properties of gases.

  16. Review of measures to control radiation

    International Nuclear Information System (INIS)

    Methods used in Canada and the U.S.A. to overcome problems in the control of radiation, to prescribe standards and to ensure that compliance with the standards is achieved are reviewed. The relevant Acts and Regulations are outlined. Options which could be applied in Australia for effecting better control of radiation are suggested

  17. Environmental radiation measurement in CTBT verification system

    International Nuclear Information System (INIS)

    well as the development of the automatic analyzing system of gamma-ray spectrum data and the atmospheric diffusion backtracking software, both of which are necessary for the NDC 2. Technologies, data, and samples obtained through the CTBT activities are supposed to be provided for the interest of the signatory nations. Equally high-quality measurement data and filter samples from the stations around the world offer opportunities, on a global scale, for detecting radionuclide dispersion, monitoring radiation levels and studying natural radioactivity, as well as supporting atmospheric studies, biological research and environmental change tracking. (author)

  18. Measurement of Radiation Pressure in an Ambient Environment

    Science.gov (United States)

    Ma, Dakang; Garrett, Joseph; Munday, Jeremy

    2015-03-01

    Light has momentum and thus exerts ``radiation pressure'' when it is reflected or absorbed due to the conservation of momentum. Micromechanical transducers and oscillators are suitable for measurement and utilization of radiation pressure due to their high sensitivities. However, other light-induced mechanical deformations such as photothermal effects often obscure accurate measurements of radiation pressure in these systems. In this work, we investigate the radiation pressure and photothermal force on an uncoated silicon nitride microcantilever under illumination by a 660 nm laser in an ambient environment. To magnify the mechanical effects, the cantilever is driven optically from dc across its resonance frequency, and the amplitude and phase of its oscillation are acquired by an optical beam deflection method and a lockin amplifier. We show that radiation pressure and photothermal effects can be distinguished through the cantilever's frequency response. Furthermore, in a radiation pressure dominant regime, our measurement of the radiation force agrees quantitatively with the theoretical calculation.

  19. Mobile non ionizing radiation measurement system

    International Nuclear Information System (INIS)

    Most regulations ask for levels of EM radiation in an area surrounding telecommunications installations. These might interest close neighbors but does not help in the risk perception of population at large. That is what makes interesting measurements on a geographic basis, that is, covering an area with certain minimum resolution. Until now this has been done statically, that is on fixed positions such as city road intersections. That equals one measurement each city block or a spatial resolution of 100 points/km2. On our experience, with an acquisition time of 6 minutes/point we do from 6 to 10 points/h or 10 to 17 h/km2. On a dynamic or mobile system we acquire simultaneously the signal from a GPS and synchronize it with the NIR measuring equipment in a portable computer. This way each measurement can be associated with a position and time. Now speed of acquisition will depend on sampling time at the meter, selectable from 0.4 to 2 sec, and displacement velocity. During acquisition we simply get a table of values. To display them in convenient form for the public at large, we utilized commercial mapping software and satellite images. We found that 4 measurements for each city block is the maximum acceptable for a reasonably meaningful display of results. A scale of colors will indicate value, where green will indicate low ones, yellow for intermediates and red for values above permitted levels. Nevertheless, since actual values are mostly well below limits, we use a scale of greens to remark small differences as we move. The system was tested on selected areas of Cordoba, population 1,3 million. With an average ''cruising speed'' of 36 km at the transport vehicle, acceptable for normal traffic conditions, we achieved 440 points/m2 in less than 20 min. Since common GPS receivers have systematic static errors on the order of +/- 6 meters plus a drift with time, our mapping must be corrected after acquisition, typically adjusted to the city streets where we

  20. Radiation detection and measurement student solutions manual

    CERN Document Server

    Wehe, David K

    2012-01-01

    This is the resource that engineers turn to in the study of radiation detection. The fourth edition takes into account the technical developments that continue to enhance the instruments and techniques available for the detection and spectroscopy of ionizing radiation. New coverage is presented on ROC curves, micropattern gas detectors, new sensors for scintillation light, and the excess noise factor. Revised discussions are also included on TLDs and cryogenic spectrometers, radiation backgrounds, and the VME standard. Engineers will gain a strong understanding of the field with this updated book.

  1. Calibration of personnel radiation measurement instruments

    International Nuclear Information System (INIS)

    Thermoluminescent analyzer (TLA) calibration procedures were used to estimate personnel radiation exposure levels at the Idaho National Engineering Laboratory (INEL). A statistical analysis is presented herein based on data collected over a six-month period in 1979 on four TLA's located in the Department of Energy Radiological and Environmental Sciences Laboratory at the INEL. Both gamma and beta radiation models are developed. Observed TLA readings of thermoluminescent dosimeters are correlated with known radiation levels. This correlation is then used to predict unknown radiation doses from future analyzer readings of personnel thermoluminescent dosimeters. The statistical techniques applied in this analysis include weighted linear regression, estimation of systematic and random error variances, prediction interval estimation using Scheffe's theory of calibration, the estimation of the ratio of the means of two normal bivariate distributed random variables and their corresponding confidence limits according to Kendall and Stuart, tests of normality, experimental design, a comparison between instruments, and quality control

  2. About Solar Radiation Intensity Measurements and Data Processing

    Directory of Open Access Journals (Sweden)

    MICH-VANCEA Claudiu

    2012-10-01

    Full Text Available Measuring the intensity of solar radiation is one of the directions of investigation necessary for the implementation of photovoltaic systems in a particular geographical area. This can be done by using specific measuring equipment (pyranometer sensors based onthermal or photovoltaic principle. In this paper it is presented a method for measuring solar radiation (which has two main components - direct radiation and diffuse radiation with sensors based on photovoltaic principle. Such data are processed for positioning solarpanels, in order their efficiency to be maximized.

  3. Pyroelectric detector development for the Radiation Measurement system

    Science.gov (United States)

    Hubbard, G. S.; Mcmurray, Robert E., Jr.; Hanel, R. P.; Dominguez, D. E.; Valero, F. P. J.; Baumann, Hilary; Hansen, W. L.; Haller, E. E.

    1993-01-01

    A new class of high detectivity pyroelectric detectors developed for optimization of the radiation measurement system within the framework of the Atmospheric Radiation Measurement program is described. These devices are intended to provide detectivities of up to about 10 exp 11 cm Hz exp 0.5/W with cooling to about 100 K required for the detector focal plane.

  4. Calibration of solar radiation measuring instruments. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bahm, R J; Nakos, J C

    1979-11-01

    A review of solar radiation measurement of instruments and some types of errors is given; and procedures for calibrating solar radiation measuring instruments are detailed. An appendix contains a description of various agencies who perform calibration of solar instruments and a description of the methods they used at the time this report was prepared. (WHK)

  5. NCRP Program Area Committee 6: Radiation Measurements and Dosimetry.

    Science.gov (United States)

    Simon, Steven L; Zeman, Gary H

    2016-02-01

    Program Area Committee (PAC) 6 of the National Council on Radiation Protection and Measurements provides guidance for radiation measurements and dosimetry--one of the most fundamental scientific areas of the Council's expertise. Seminal reports published by PAC 6 over many decades have documented the scientific and technical foundations of radiation measurements and dosimetry for generations of radiation scientists and radiation protection professionals. Ongoing work of PAC 6 is driven by advancing technology, such as development of new types of instruments, biodosimetry and nanotechnology; by evolving understanding of radiation hazards, such as effects on the lens of the eye and risks as from some high-dose medical imaging procedures; and by new situations faced in the modern socio-political environment including radiological and nuclear threats. The activities of PAC 6 are intended to formulate and document the dosimetric framework for radiological science to address these ever-emerging challenges. PMID:26717161

  6. Radiation tolerant isolation amplifiers for temperature measurement

    International Nuclear Information System (INIS)

    This paper concentrates on the selection of radiation tolerant isolation amplifiers, which are suitable for the signal conditioners for cryogenic system in the Large Hadron Collider (LHC). The evolution and the results of different commercial isolation amplifiers' parameters under neutron and gamma radiation are presented. In most cases, the tested isolation amplifiers' input offset voltage, bias currents and output offset voltage hardly changed during the radiation. The DC gain in input stage was only affected for some isolation amplifiers with a small open loop gain. Transmission coefficient showed decrease for all the tested isolation amplifiers. Also, the DC output voltage increased and the ripple voltage decreased for all the build-in isolated regulators. In addition, results on 1B41 signal conditioner showed that it was tolerant to 7-8x1012 n/cm2, which was 50% higher than the expected dose in the LHC

  7. Orbit determination of Transneptunian objects and Centaurs for the prediction of stellar occultations

    CERN Document Server

    Desmars, J; Braga-Ribas, F; Vieira-Martins, R; Assafin, M; Vachier, F; Colas, F; Ortiz, J L; Duffard, R; Morales, N; Sicardy, B; Gomes-Júnior, A R; Benedetti-Rossi, G

    2015-01-01

    The prediction of stellar occultations by Transneptunian objects and Centaurs is a difficult challenge that requires accuracy both in the occulted star position as for the object ephemeris. Until now, the most used method of prediction involving tens of TNOs/Centaurs was to consider a constant offset for the right ascension and for the declination with respect to a reference ephemeris. This offset is determined as the difference between the most recent observations of the TNO and the reference ephemeris. This method can be successfully applied when the offset remains constant with time. This paper presents an alternative method of prediction based on a new accurate orbit determination procedure, which uses all the available positions of the TNO from the Minor Planet Center database plus sets of new astrometric positions from unpublished observations. The orbit determination is performed through a numerical integration procedure (NIMA), in which we develop a specific weighting scheme. The NIMA method was appli...

  8. Solar Panel Integration as an Alternate Power Source on Centaur 2 (SPIAPS)

    Science.gov (United States)

    Gebara, Christine A.; Schuetze, Nich A.; Knochel, Aviana M.; Magruder, Darby F.

    2011-01-01

    The dream of exploration has inspired thousands throughout time. Space exploration, in particular, has taken the past century by storm and caused a great advance in technology. In this project, a retractable solar panel array will be developed for use on the Centaur 2 Rover. Energy generated by the solar panels will go to power the Centaur 2 Robot (C2) or Regolith & Environment Science & Oxygen & Lunar Volatile Extraction (RESOLVE) payload, an in-situ resource utilization project. Such payload is designed to drill into lunar and Martian terrain as well as be able to conduct other geological testing; RESOLVE is slated for testing in 2012. Ultimately, this project will fit into NASA s larger goal of deep space exploration as well as long term presence outside Earth s orbit.

  9. Dynamical studies of Centaurs and their sources: interactions with the Main Belt

    Science.gov (United States)

    Galiazzo, Mattia; Carruba, Valerio; Wiegert, Paul

    2015-08-01

    Centaurs are objects whose orbits are found between those of the giant planets. Their main source is presumed to be the Trans-Neptunian objects (TNOs), and they are among the sources of Near-Earth Objects. Their dynamical evolution is heavily influenced by close encounters with giant planets and some of them were most likely scattered into their current orbits. After experiencing close encounters with the giant planets, Centaurs may have their eccentricity increased to values large enough to reach the main belt (aplan to investigate if close encounters with large (diameters larger than 100 km) outer Solar System bodies could have been responsible for the scattering of V-type asteroids from the Vesta family beyond the 3J:1 mean motion resonance, into the central and outer main belt.

  10. Ground truth data for test sites (SL-4). [thermal radiation brightness temperature and solar radiation measurments

    Science.gov (United States)

    1974-01-01

    Field measurements performed simultaneous with Skylab overpass in order to provide comparative calibration and performance evaluation measurements for the EREP sensors are presented. Wavelength region covered include: solar radiation (400 to 1300 nanometer), and thermal radiation (8 to 14 micrometer). Measurements consisted of general conditions and near surface meteorology, atmospheric temperature and humidity vs altitude, the thermal brightness temperature, total and diffuse solar radiation, direct solar radiation (subsequently analyzed for optical depth/transmittance), and target reflectivity/radiance. The particular instruments used are discussed along with analyses performed. Detailed instrument operation, calibrations, techniques, and errors are given.

  11. Mathematical simulation of gamma-radiation angle distribution measurements

    International Nuclear Information System (INIS)

    We developed mathematical model of the facility for gamma-radiation angle distribution measurement and calculated response functions for gamma-radiation intensities. We developed special software for experimental data processing, the 'Shelter' object radiation spectra unfolding and Sphere detector (ShD) angle resolution estimation. Neuronet method using for detection of the radiation directions is given. We developed software based on the neuronet algorithm, that allows obtaining reliable distribution of gamma-sources that make impact on the facility detectors at the measurement point. 10 refs.; 15 figs.; 4 tab

  12. Uncertainty of dose measurement in radiation processing

    DEFF Research Database (Denmark)

    Miller, A.

    1996-01-01

    running debate and presents the author's view, which is based upon experience in radiation processing dosimetry. The origin of all uncertainty components must be identified and can be classified according to Type A and Type B, but it is equally important to separate the uncertainty components into those...

  13. Radiation distribution measurement for forest plant canopies tracing

    Science.gov (United States)

    Wan, Xuefen; Cui, Jian; Yang, Yi; Liu, Hui

    2012-11-01

    Plant canopies structures are important biophysical parameters required in many ecological and climate models. To obtain precise canopies characteristic, the radiation distribution in forest gap should be tracing. In this paper, a radiation transmission measuring method with gyroscope correction for forest gap radiation distribution measurement is present. And a Zigbee wireless network is imbedded for communicating between portable full-trace radiation detector and host computer. Using the solar beam as a probe, the measuring nodes collect radiation distribution in forest gap. Because the constant pace of operator in forest and other outdoor occasion is hard to validate, radiation distribution curves suffer some error. We present a Forest radiation distribution meter with Gyro correction for TRAC measuring. In this meter, A Gyroscope records transect route data and provide speed correction for canopy gaps curve in tracing route. A Microchip PIC16F877 MCU is employed for radiation data collection. The collected data is sent to central station by Zigbee wireless network or CF376 in-line USB flash drives/SD card. Solar radiation spike data and other environment parameters (Temperature and Humidity) are sampled simultaneously. So the gap removal processes suffer less error. A portable node provides full-trace radiation distribution. Host computer can get potential relationship in tracing-line LAI and FPAR and compute them in long-term. A portable full-trace radiation detector and host computer is tested. The experimental results show our design could be a competitive candidate for radiation distribution measurement for forest plant canopies tracing.

  14. The Diverse Solar Phase Curves of Distant Icy Bodies. Part I: Photometric Observations of 18 Trans-Neptunian Objects, 7 Centaurs, and Nereid

    CERN Document Server

    Rabinowitz1, D L; Tourtellotte3, S W; Rabinowitz1, David L.; Schaefer2, Bradley E.; Tourtellotte3, Suzanne W.

    2006-01-01

    We have measured the solar phase curves in B, V, and I for 18 Trans-Neptunian Objects, 7 Centaurs, and Nereid and determined the rotation curves for 10 of these targets. For each body, we have made ~100 observations uniformly spread over the entire visible range. We find that all the targets except Nereid have linear phase curves at small phase angles ( 3 deg, the Centaurs (54598) Bienor and (32532) Thereus have phase curves that flatten. The recently discovered Pluto-scale bodies (2003 UB313, 2005 FY9, and 2003 EL61), like Pluto, have neutral colors compared to most TNOs and small phase coefficients (< 0.1 mag/deg). Together these two properties are a likely indication for large TNOs of high-albedo, freshly coated icy surfaces. We find several bodies with significantly wavelength-dependent phase curves. The TNOs (50000) Quaoar, (120348) 2004 TY364 (47932), and 2000 GN171 have unusually high I-band phase coefficients (0.290+/-0.038, 0.413+/-0.064, 0.281+/-0.033 mag/deg, respectively) and much lower coeffic...

  15. Optical tomography for measuring dose distribution in radiation therapy

    Directory of Open Access Journals (Sweden)

    Kauppinen Matti

    2014-01-01

    Full Text Available The dosimetry is used to verify the dose magnitude with artificial samples (phantoms before giving the planned radiation therapy to the patient. Typically, dose distribution is measured only in a single point or on a two-dimensional matrix plane. New techniques of radiation therapy ensure more detailed planning of radiation dose distribution which will lead to the need of measuring the radiation dose distribution three-dimensionally. The gel dosimetry is used to indicate and determine the ionizing radiation three-dimensionally. The radiation causes changes in chemical properties of the gel. The radiation dose distribution is defined by measuring the chemical changes. A conventional method is the magnetic resonance imaging and a new possibility is optical computed tomography (optical-CT. The optical-CT is much cheaper and more practical than magnetic resonance imaging. In this project, an optical-CT based method device was built by aiming at low material costs and a simple realization. The constructed device applies the charge coupled device camera and fluorescent lamp technologies. The test results show that the opacity level of the radiated gel can be measured accurately enough. The imaging accuracy is restricted by the optical distortion, e. g. vignetting, of the lenses, the distortion of a fluorescent lamp as the light source and a noisy measuring environment.

  16. 47 CFR 15.33 - Frequency range of radiated measurements.

    Science.gov (United States)

    2010-10-01

    ... measurement of radiated emissions and, in the case of receivers, the measurement to demonstrate compliance... (MHz) Upper frequency of measurement range (MHz) Below 1.705 30. 1.705-108 1000. 108-500 2000. 500-1000... device operates or tunes (MHz) Upper frequency of measurement range (MHz) Below 1.705 30 1.705-10 400...

  17. Measurements of environmental radiations and radioactivities in Toki, (3)

    International Nuclear Information System (INIS)

    In this issue two reports are given from the 1983 IPP-Toki collaborational works of surveying environmental radiations and radioactivities over the Toki area. One of them is concerned with the TLD observations of radiation levels by a team of local school teachers, and the other shows the results of sample measurements due to gamma- and alpha- spectrometry by the IPP group. In addition, a map of background radiation levels in Japan is included for the reference use. (author)

  18. Diffraction measurements at sources of synchrotron radiation

    Czech Academy of Sciences Publication Activity Database

    Hašek, Jindřich

    Vol. 2a. Praha : Czech and Slovak Crystallographic Association, 2008, s. 15-16. ISSN 1211-5894. [Struktura 2008 - Colloquium of the Czech and Slovak Crystallographic Association. Valtice (CZ), 16.06.2008-20.06.2008] R&D Projects: GA AV ČR IAA500500701; GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : synchrotron radiation Subject RIV: CE - Biochemistry

  19. Radiation dose measurements in intravenous pyelography

    International Nuclear Information System (INIS)

    Intravenous pyelography (IVP) and micturition cystourethrography (MCU) are the standard procedures in the radiological examination of children with urinary tract infections and in the control of these children. Gonad protection against radiation is not possible in MCU, but concerning the girls partly possible in IVP. It is of major importance to know the radiation dose in these procedures, especially since the examination is often repeated in the same patients. All IVP were done by means of the usual technique including possible gonad protection. The thermoluminescence dosimeter was placed rectally in the girls and fixed on the scrota in the boys. A total of 50 children was studied. Gonad dose ranged from 140 to 200mR in the girls and from 20 to 70mR in the boys (mean values). The radiation dose in IVP is very low compared to that of MCU, and from this point of view IVP is a dose saving examination in the control of children with urinary tract infections

  20. Radiation protection measures for hot cell sanitation

    International Nuclear Information System (INIS)

    The cell 5 of the Hot Cell Facility of the Kernforschungszentrum Karlsruhe GmbH (KfK) was to be restored and reequipped after 12 years of operation. The decontamination work was first done remotely controlled and afterwards by 38 persons entering the cell, which took about 2 months. The radiation protection methods and personal dosimetry systems are described. At the beginning of the work the γ-dose rate amounted up to 900 mSv/h. After completion of the remotely controlled decontamination work the γ-dose rate decreased to 1.5 mSv/h. At that time the (α+β-contamination was 105 Bq/cm2. Till the end of the work the removable activity dropped to 102 - 103 Bq/cm2 for β-radiation, to 0.3 - 30 Bq/cm2 for α-radiation and the local dose rate to about 0.03 mSv/h. During the work the accumulated collective doses were listed for breast, hand, head, gonads and foot. In the figure the development with the time of the doses for breast and hand is shown. During restoration work of the cell the accumulated collective whole-body dose amounted to 30 mSv. (orig.)

  1. Measuring radiation dose to patients undergoing fluoroscopically-guided interventions

    Science.gov (United States)

    Lubis, L. E.; Badawy, M. K.

    2016-03-01

    The increasing prevalence and complexity of fluoroscopically guided interventions (FGI) raises concern regarding radiation dose to patients subjected to the procedure. Despite current evidence showing the risk to patients from the deterministic effects of radiation (e.g. skin burns), radiation induced injuries remain commonplace. This review aims to increase the awareness surrounding radiation dose measurement for patients undergoing FGI. A review of the literature was conducted alongside previous researches from the authors’ department. Studies pertaining to patient dose measurement, its formalism along with current advances and present challenges were reviewed. Current patient monitoring techniques (using available radiation dosimeters), as well as the inadequacy of accepting displayed dose as patient radiation dose is discussed. Furthermore, advances in real-time patient radiation dose estimation during FGI are considered. Patient dosimetry in FGI, particularly in real time, remains an ongoing challenge. The increasing occurrence and sophistication of these procedures calls for further advances in the field of patient radiation dose monitoring. Improved measuring techniques will aid clinicians in better predicting and managing radiation induced injury following FGI, thus improving patient care.

  2. Environmental Outdoor Gamma Radiation Measured at Soreq NRC Israel

    International Nuclear Information System (INIS)

    Environmental monitoring is concerned with the measurements of the natural radiation arising from natural radioactive materials present in the surroundings and from cosmic rays .Indoor background radiation at ten different locations in Israel was reported earlier (l). A detailed outdoor gamma-ray examination at NRC-Soreq, which operates a 5 MW IRR-l pool reactor, is presented in this work

  3. Traceability of radiation measurements: musings of a user

    Energy Technology Data Exchange (ETDEWEB)

    Kathren, R.L.

    1980-04-01

    Although users of radiation desire measurement traceability for a number of reasons, including legal, regulatory, contractual, and quality assurance requirements, there exists no real definition of the term in the technical literature. Definitions are proposed for both traceability and traceability to the National Bureau of Standards. The hierarchy of radiation standards is discussed and allowable uncertainties are given for each level. Areas of need with respect to radiation standards are identified, and a system of secondary radiation calibration laboratories is proposed as a means of providing quality calibrations and traceability on a routine basis.

  4. Traceability of radiation measurements: musings of a user

    International Nuclear Information System (INIS)

    Although users of radiation desire measurement traceability for a number of reasons, including legal, regulatory, contractual, and quality assurance requirements, there exists no real definition of the term in the technical literature. Definitions are proposed for both traceability and traceability to the National Bureau of Standards. The hierarchy of radiation standards is discussed and allowable uncertainties are given for each level. Areas of need with respect to radiation standards are identified, and a system of secondary radiation calibration laboratories is proposed as a means of providing quality calibrations and traceability on a routine basis

  5. Device for measuring the beta radiation of radioactive substances

    International Nuclear Information System (INIS)

    The switching device for measuring radiaoactive rare gases has two large area counting tubes operated with argon methane gas. Two anti-coincidence stages are provided in the evaluation electronics to suppress the background gamma radiation. (DG)

  6. Nuclear radiation-warning detector that measures impedance

    Science.gov (United States)

    Savignac, Noel Felix; Gomez, Leo S; Yelton, William Graham; Robinson, Alex; Limmer, Steven

    2013-06-04

    This invention is a nuclear radiation-warning detector that measures impedance of silver-silver halide on an interdigitated electrode to detect light or radiation comprised of alpha particles, beta particles, gamma rays, X rays, and/or neutrons. The detector is comprised of an interdigitated electrode covered by a layer of silver halide. After exposure to alpha particles, beta particles, X rays, gamma rays, neutron radiation, or light, the silver halide is reduced to silver in the presence of a reducing solution. The change from the high electrical resistance (impedance) of silver halide to the low resistance of silver provides the radiation warning that detected radiation levels exceed a predetermined radiation dose threshold.

  7. A portable scintillation spectrometer for environmental radiation measurements

    International Nuclear Information System (INIS)

    A portable scintillation spectrometer for field use, applicable to the in situ measurements of environmental radiation, has been developed. It consists of a 3 in. spherical NaI (Tl) scintillation detector, an interface and a commercial two channel audio tape recorder. The whole system of the spectrometer weighs 7.3 kg, and can be housed in a small suitcase (''air bag'', 34 x 45 x 21 (cm)). Several examples of its application to environmental radiation measurements are presented. (author)

  8. Radiation risk estimation based on measurement error models

    CERN Document Server

    Masiuk, Sergii; Shklyar, Sergiy; Chepurny, Mykola; Likhtarov, Illya

    2016-01-01

    This monograph discusses statistics and risk estimates applied to radiation damage under the presence of measurement errors. The first part covers nonlinear measurement error models, with a particular emphasis on efficiency of regression parameter estimators. In the second part, risk estimation in models with measurement errors is considered. Efficiency of the methods presented is verified using data from radio-epidemiological studies.

  9. Development of radiation detection and measurement systems

    Energy Technology Data Exchange (ETDEWEB)

    Moon, B. S.; Ham, C. S.; Chung, C. E. and others

    2000-03-01

    This report contains descriptions on the following six items. The first item is the result of a study on CsI(TI) crystals with their light emitting characteristics and the result of a study on plastic scintillators. The second item is the result of a study on advanced radiation detectors and includes experiments for the effect of using a Compton suppressor with an HPGe detector. For the third item, we describe the results of a design work done using EGS4 for a thickness gauge, a density gauge, and a level gauge. The fourth item contains descriptions on the prototype circuit systems developed for a level gauge, a thickness gauge, and for a survey meter. The fifth part contains the computed tomography algorithm and a prototype scanning system developed for a CT system. As the sixth and the last item, we describe the prototype high precision heat source and the prototype heat-voltage converter which we have designed and fabricated.

  10. Development of radiation detection and measurement systems

    International Nuclear Information System (INIS)

    This report contains descriptions on the following six items. The first item is the result of a study on CsI(TI) crystals with their light emitting characteristics and the result of a study on plastic scintillators. The second item is the result of a study on advanced radiation detectors and includes experiments for the effect of using a Compton suppressor with an HPGe detector. For the third item, we describe the results of a design work done using EGS4 for a thickness gauge, a density gauge, and a level gauge. The fourth item contains descriptions on the prototype circuit systems developed for a level gauge, a thickness gauge, and for a survey meter. The fifth part contains the computed tomography algorithm and a prototype scanning system developed for a CT system. As the sixth and the last item, we describe the prototype high precision heat source and the prototype heat-voltage converter which we have designed and fabricated

  11. Radiometric modulation measuring device of intensity of optical radiation

    Directory of Open Access Journals (Sweden)

    A. P. Yanenko

    2014-04-01

    Full Text Available Introduction. The paper proposed a block diagram of radiometric measuring the intensity of optical radiation from modulation conversion parameter input . To assess the intensity of use periodically comparing the reference signal (shaded and measurement (open photodi-odes. Studies. The proposed radiometric modulation meter provides increased sensitivity and measurement accuracy by reducing the influence of dark current measurement and reference photodiodes and compensation intrinsic noise measuring channel through their periodic anti-phase comparison.

  12. Collaboration between TAEA and ANASA for developing radiation measurement instruments

    International Nuclear Information System (INIS)

    Full text: Collaboration between TAEA and ANASA on the subject of 'Developing Radiation Measurement Instruments' has started by the organization of TAEA-TUDNAEM in 2002. Firstly the model NEB.300 'Dose-Rate Meter' equipped with external scintillation probe was designed and a prototype produced. Scintillation Probe of the instrument is produced by ANASA personnel, the electronics measurement circuits and other units are developed by TAEA personnel. The NEB.300 Dose-Rate Meter is a radiation meter designed to measure especially very low radiation with external scintillation probe. It has wide application range, because of its warning specification for protecting personnel working with radiation sources, and because of its measuring and monitoring specifications for surveying, evaluating and carrying the radioactive materials. Advanced micro controller technology is used to cover problems of radiation measurement. Control by micro controller enables reliable, stable measurement and display of low level dose rate fields. It makes possible the simultaneous measurement of both dose and dose rate values with scintillation detector sensitive to gamma and X-rays. Set to different dose rate or dose levels it warns audibly. Measurements are shown on the 2 1/2 digits auto range display besides other warnings

  13. Radiation quantities, units and measurements. Final report 1999

    International Nuclear Information System (INIS)

    The determination of human exposure to radiation and radioactivity, whether arising from environmental exposures, medical practice or industrial activities, requires a fundamental set of quantities and units with which exposures can be specified and the means and ability to make measurements which yield results in terms of these quantities and units. Radiation protection then, as well as effective use of radiation in medical applications, requires the capability to accurately quantify the characteristics and extent of radiation exposure, so that appropriate and useful assessments of the potential health consequences and risks, whether for protection of the public and workers or for diagnosis and treatment of disease, can be formulated. The work carried out via this concerted action on ''Radiation quantities, units and measurements'' has addressed these needs. Measurement of radiation is a complex subject and is a science in itself. Yet many users of radiation who need to make radiation measurements cannot be expected to become experts in this particular field. They need authoritative guidance on how to deal with the measurement problems connected with their particular use of radiation. The work carried out pursuant to this concerted action has resulted in publications that meet this need. Important achievements include the publication of seven new ICRU reports, the completion of all but the printing of three other ICRU reports, completion of the drafting work on two other reports, the development of many others reports and the initiation of seven new activities that will result in ICRU reports representing important future contribution to the needs identified in this project. (orig.)

  14. Measurement of radiative widths at COMPASS

    CERN Document Server

    Krämer, Markus

    2014-01-01

    COMPASS is a multipurpose fixed-target experiment at the CERN SPS, which addresses a wide variety of physic topics, in particular the structure and spectroscopy of hadrons. Diffractive dissociation of pions on nuclear targets allows for clean access to the light meson spectrum. In addition meson production can be studied in pion-photon reactions via the Primakoff effect, where high-energetic pions react with the quasi-real photon field surrounding the target nuclei. At low pion-photon center-of-mass energies, these reactions are governed by chiral dynamics and contain information relevant for chiral perturbation theory. At higher energies, resonances are produced and their radiative coupling is investigated. During a short run using a 190GeV $\\pi^-$ beam and a lead target in the year 2004, 3 million exclusive $\\pi^-\\pi^-\\pi^+$ events in the region of small squared four-momentum transfer, i.e. t' < 0:01GeV$^2$=c$^2$, have been recorded. At very low t' < 0:001GeV$^2$=c$^2$, the contribution from electroma...

  15. Measurement of man's exposure to external radiation

    International Nuclear Information System (INIS)

    After outlining briefly the rationale for personnel radiation monitoring with integrating detectors, a review is presented of some developments which have taken place in personnel and environmental dosimetry during the past 3.5 years. The results of a pilot field experiment concerning the stability of film and thermoluminescent dosimeters (TLDs) in four Latin-American countries are summarized. It shows that film dosimeters should be used only with caution, and in locations with a moderate climate. A survey is being conducted on the current status and trends in personnel monitoring, involving detailed questioning of over 150 laboratories in about forty countries to obtain information on the type of service and detectors, evaluation and recordkeeping, additional applications, problem and development areas, intercomparisons, practical experiences with different systems, administrative and legal aspects, etc. According to the preliminary results, the trend is away from photographic film and towards mostly automatic TLD systems, not only in the industrialized countries but also in several of the larger and more advanced developing countries. The need for higher quality standards and frequent performance tests under realistic conditions is emphasized. Differences in the requirements for personnel and

  16. The definition analyses of radiation temperature measurement area

    Institute of Scientific and Technical Information of China (English)

    Fu Tairan; Cheng Xiaofang; Zhong Maohua

    2008-01-01

    In the research of primary spectrum pyrometry, this paper discussed the definition problem of radiation tem-perature measurement area based on the measurement coordinates. For the linear spectrum emissivity model and im-proved monotonic spectrum emissivity model, the characteristics of radiation temperature measurement area restricted by the measurement coordinates were theoretically analyzed, through the investigations of the temperature and emissivity co-ordinate axes. Choosing the specific primary spectrum pyrometer as an example in applications, the theoretical area of radiation temperature measurement of this pyrometer was given and it was verified through blackbody experiments. The discussions of this paper will provide the necessary foundation for the theory research development of primary spectrum pyrometry and the realization of technical applications.

  17. Radiation protection measures in the case of incidents and radiation accidents

    International Nuclear Information System (INIS)

    Measures to be taken in the case of radiation accidents connected with an unusually high radiation exposure to persons, the amounts of which exceed the limiting values, with depend on whether there has been an external or an internal exposure. In order to give further treatment in the case of whole-body or partial-body irradiation, it is necessary to estimate the exposure dose. In nuclear medicine the accident doses are generally low, i.e. acute radiation damage does not occur here, and immediate measures are not necessary. Therapeutic measures in the case of incorporation accidents are only necessary when the maximum amounts for the nuclide in question recommended by the ICRP has been reached or exceeded in the organism. However, decorporation measures ought to be carried out only by qualified radiation protection physicians. The type of radiation accident which occurs most frequently in nuclear medicine is radiation exposure as a result of contamination. If in the case of contamination of a person the measurement exceeds the radioactivity limit, the decontamination measures are necessary. In the present contribution, these measures for cases without injuries are described in detail. (orig./HP)

  18. Measurement of radiation loss in TRIAM-IM

    International Nuclear Information System (INIS)

    In the superconducting strong magnetic field tokamak, TRIAM-IM, in order to grasp the radiation loss by the electromagnetic waves from plasma, the metallic film bolometer of one channel was designed and made, and the radiation power was measured. As the result, the proportion of radiation loss to input power was able to be evaluated as 50 - 70% in the case of ohmic heating discharge, and 35 - 50% in the case of lower hybrid wave current drive (LHCD). According to the Lawson criterion, in order to realize nuclear fusion power generation, it is necessary to efficiently confine very high temperature, high density plasma and to decrease various losses. If the polyvalent ions accompanying the mixing of impurities are present in hydrogen plasma, the radiation loss from the plasma increases, and the Lawson criterion cannot be satisfied. In the TRIAM-IM, it was decided to measure directly radiation power for the first time with a bolometer. Steady long hour discharge was successfully carried out by LHCD. The strong toroidal magnetic field experimental device TRIAM-IM, the kinds of bolometers and the selection, the principle of bolometer, the outline of the apparatus, output processing, calibration, the experimental results of ohmic heating discharge and LHCD are described. The radiation energy emitted from plasma was changed to thermal energy with a radiation absorber, of which the temperature rise was measured by electric resistance change, and by the voltage change of a bridge circuit. (K.I.)

  19. ISS and Space Shuttle Radiation Measurements at Solar Minimum

    Science.gov (United States)

    Gaza, Ramona; Welton, Andrew; Dunegan, Audrey; Lee, Kerry

    2011-01-01

    A summary of 2008-2011 ISS and Space Shuttle radiation dosimetry results for inside vehicle radiation monitoring in low-Earth orbit will be presented. Results include new data from ISS Expedition 22-25/20A radiation area monitors (RAM) and Shuttle Missions STS127-STS133 passive radiation dosimeters (PRD). ISS 20A radiation measurement locations included three Node 2 crew quarters locations at NOD2S5_CQ, NOD2P5_CQ and CQ-3 (Deck), as well as ESA Columbus, and JAXA Kibo locations. ISS 20A and STS127-STS133 missions were flown at 51.6 inclination with an altitude range of 330-350 km. The passive radiation results will be presented in terms of measured daily dose obtained using luminescence detectors (i.e., Al2O3:C, LiF:Mg,Ti and CaF2:Tm). In addition, preliminary results from the DOSIS 2 Project, in collaboration with the German Space Agency (DLR) will be presented. SRAG s participation to the DOSIS 2 exposure on ISS (11/16/2009-05/26/2010) involved passive radiation measurements at 10 different shielding locations inside the ESA Columbus Module.

  20. Radiation Environment Variations at Mars - Model Calculations and Measurements

    Science.gov (United States)

    Saganti, Premkumar; Cucinotta, Francis

    Variations in the space radiation environment due to changes in the GCR (Galactic Cosmic Ray) from the past (#23) solar cycle to the current one (#24) has been intriguing in many ways, with an unprecedented long duration of the recent solar minimum condition and a very low peak activity of the current solar maximum. Model calculated radiation data and assessment of variations in the particle flux - protons, alpha particles, and heavy ions of the GCR environment is essential for understanding radiation risk and for any future intended long-duration human exploration missions. During the past solar cycle, we have had most active and higher solar maximum (2001-2003) condition. In the beginning of the current solar cycle (#24), we experienced a very long duration of solar minimum (2009-2011) condition with a lower peak activity (2013-2014). At Mars, radiation measurements in orbit were obtained (onboard the 2001 Mars Odyssey spacecraft) during the past (#23) solar maximum condition. Radiation measurements on the surface of Mars are being currently measured (onboard the Mars Science Laboratory, 2012 - Curiosity) during the current (#24) solar peak activity (August 2012 - present). We present our model calculated radiation environment at Mars during solar maxima for solar cycles #23 and #24. We compare our earlier model calculations (Cucinotta et al., J. Radiat. Res., 43, S35-S39, 2002; Saganti et al., J. Radiat. Res., 43, S119-S124, 2002; and Saganti et al., Space Science Reviews, 110, 143-156, 2004) with the most recent radiation measurements on the surface of Mars (2012 - present).

  1. Proposal of new measure of radiation dose for a better understanding of radiation for the public

    International Nuclear Information System (INIS)

    New nuclear power plants need to be built to provide clean energy which does not generate carbon dioxide. Building such plants requires agreement by the public on the necessity for the development of nuclear power programs. It is therefore important to provide the general public with an understanding of the true situation in matters of radiation and to assuage irrational anxieties. A new method of radiation representation is proposed which is based on the annual absorbed or exposure dose equivalent originating from natural radiation. The representation is considered useful to enable the general public to recognize the reality of the influence of exposure to natural radiation. A comparison in made between the risk of radiation and other toxic materials. The toxicity of chemical materials is measured by amounts occurring naturally in the human body in a method similar to that used in the case of nuclear radiation. (author)

  2. Carbonization in Titan Tholins: implication for low albedo on surfaces of Centaurs and trans-Neptunian objects

    Science.gov (United States)

    Giri, Chaitanya; McKay, Christopher P.; Goesmann, Fred; Schäfer, Nadine; Li, Xiang; Steininger, Harald; Brinckerhoff, William B.; Gautier, Thomas; Reitner, Joachim; Meierhenrich, Uwe J.

    2016-07-01

    Astronomical observations of Centaurs and trans-Neptunian objects (TNOs) yield two characteristic features - near-infrared (NIR) reflectance and low geometric albedo. The first feature apparently originates due to complex organic material on their surfaces, but the origin of the material contributing to low albedo is not well understood. Titan tholins synthesized to simulate aerosols in the atmosphere of Saturn's moon Titan have also been used for simulating the NIR reflectances of several Centaurs and TNOs. Here, we report novel detections of large polycyclic aromatic hydrocarbons, nanoscopic soot aggregates and cauliflower-like graphite within Titan tholins. We put forth a proof of concept stating the surfaces of Centaurs and TNOs may perhaps comprise of highly `carbonized' complex organic material, analogous to the tholins we investigated. Such material would apparently be capable of contributing to the NIR reflectances and to the low geometric albedos simultaneously.

  3. Orbit determination of trans-Neptunian objects and Centaurs for the prediction of stellar occultations

    Science.gov (United States)

    Desmars, J.; Camargo, J. I. B.; Braga-Ribas, F.; Vieira-Martins, R.; Assafin, M.; Vachier, F.; Colas, F.; Ortiz, J. L.; Duffard, R.; Morales, N.; Sicardy, B.; Gomes-Júnior, A. R.; Benedetti-Rossi, G.

    2015-12-01

    Context. The prediction of stellar occultations by trans-Neptunian objects (TNOs) and Centaurs is a difficult challenge that requires accuracy both in the occulted star position and in the object ephemeris. Until now, the most used method of prediction, involving dozens of TNOs/Centaurs, has been to consider a constant offset for the right ascension and for the declination with respect to a reference ephemeris, usually the latest public version. This offset is determined as the difference between the most recent observations of the TNO/Centaur and the reference ephemeris. This method can be successfully applied when the offset remains constant with time, i.e. when the orbit is stable enough. In this case, the prediction even holds for occultations that occur several days after the last observations. Aims: This paper presents an alternative method of prediction, based on a new accurate orbit determination procedure, which uses all the available positions of the TNO from the Minor Planet Center database, as well as sets of new astrometric positions from unpublished observations. Methods: Orbits were determined through a numerical integration procedure called NIMA, in which we developed a specific weighting scheme that considers the individual precision of the observation, the number of observations performed during one night by the same observatory, and the presence of systematic errors in the positions. Results: The NIMA method was applied to 51 selected TNOs and Centaurs. For this purpose, we performed about 2900 new observations in several observatories (European South Observatory, Observatório Pico dos Dias, Pic du Midi, etc.) during the 2007-2014 period. Using NIMA, we succeed in predicting the stellar occultations of 10 TNOs and 3 Centaurs between July 2013 and February 2015. By comparing the NIMA and Jet Propulsion Laboratory (JPL) ephemerides, we highlight the variation in the offset between them with time, by showing that, generally, the constant offset

  4. Terrestrial radiation measurements in Marshall Islands

    International Nuclear Information System (INIS)

    With the prospect of habitation in the near future, radiological surveys were undertaken of Enewetak and Bikini Atolls to provide a basis for determining whether or not the atolls can be safely reinhabited. The surveys included all of the forty islands within Enewetak Atoll, but only the two principal islands, Bikini and Eneu Islands, of Bikini Atoll. These atolls were former U.S. nuclear weapons test sites in the Pacific. Integral parts of the surveys were the measurements of the distributions of radioactivity in the soil and the resulting gamma ray exposure rates for external dose estimation. Numerous soil samples were collected from both atolls for analysis by Ge (Li) gamma spectrometry and by wet chemistry techniques. At Enewetak Atoll the gamma exposure rates were measured by TLDs and a helicopter-borne array of Nal detectors, while at Bikini Atoll portable Nal detectors, pressurized ion-chambers, and TLDs were utilized. The predominant species measured in the soil samples collected from both atolls were 90Sr, 239,240Pu, 137Cs and 60Co with the latter two nuclides being the primary contributors to the gamma-ray exposure rates. The geographical distribution of the exposure rates measured on both atolls, was highly variable ranging from less than 1 μR/h on islands that had not been impacted radiologically by the testing program, to over 100 μR/h near weapon detonation sites. Thus, within Enewetak Atoll, the highest soil activities and gamma-ray exposure rates were measured on the northern islands, where the weapons testing had been most intense. Bikini Island exhibited contamination levels that were considerably higher than those on Eneu Island. Generally, the highest activity levels were observed within the island interiors or in proximity to ground zero sites, and could usually be related to the surrounding vegetation density. The island of Yvonne, within Enewetak Atoll, is the most severely contaminated land area. Particles containing as much as several

  5. ACREM: A new air crew radiation exposure measuring system

    International Nuclear Information System (INIS)

    Cosmic radiation has already been discovered in 1912 by the Austrian Nobel Laureate Victor F. Hess. After Hess up to now numerous measurements of the radiation exposure by cosmic rays in different altitudes have been performed, however, this has not been taken serious in view of radiation protection.Today, with the fast development of modern airplanes, an ever increasing number of civil aircraft is flying in increasing altitudes for considerable time. Members of civil aircrew spending up to 1000 hours per year in cruising altitudes and therefore are subject to significant levels of radiation exposure. In 1990 ICRP published its report ICRP 60 with updated excess cancer risk estimates, which led to significantly higher risk coefficients for some radiation qualities. An increase of the radiation weighting factors for mean energy neutron radiation increases the contribution for the neutron component to the equivalent dose by about 60%, as compared to the earlier values of ICRP26. This higher risk coefficients lead to the recommendation of the ICRP, that cosmic radiation exposure in civil aviation should be taken into account as occupational exposure. Numerous recent exposure measurements at civil airliners in Germany, Sweden, USA, and Russia show exposure levels in the range of 3-10 mSv/year. This is significantly more than the average annual dose of radiation workers (in Austria about 1.5 mSv/year). Up to now no practicable and economic radiation monitoring system for routine application on board exits. A fairly simple and economic approach to a practical, active in-flight dosimeter for the assessment of individual crew exposure is discussed in this paper

  6. Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs)

    International Nuclear Information System (INIS)

    P/2011 S1 (Gibbs) is an outer solar system comet or active Centaur with a similar orbit to that of the famous 29P/Schwassmann-Wachmann 1. P/2011 S1 (Gibbs) has been observed by the Pan-STARRS 1 (PS1) sky survey from 2010 to 2012. The resulting data allow us to perform multi-color studies of the nucleus and coma of the comet. Analysis of PS1 images reveals that P/2011 S1 (Gibbs) has a small nucleus <4 km radius, with colors g P1 – r P1 = 0.5 ± 0.02, r P1 – i P1 = 0.12 ± 0.02, and i P1 – z P1 = 0.46 ± 0.03. The comet remained active from 2010 to 2012, with a model-dependent mass-loss rate of ∼100 kg s–1. The mass-loss rate per unit surface area of P/2011 S1 (Gibbs) is as high as that of 29P/Schwassmann-Wachmann 1, making it one of the most active Centaurs. The mass-loss rate also varies with time from ∼40 kg s–1 to 150 kg s–1. Due to its rather circular orbit, we propose that P/2011 S1 (Gibbs) has 29P/Schwassmann-Wachmann 1-like outbursts that control the outgassing rate. The results indicate that it may have a similar surface composition to that of 29P/Schwassmann-Wachmann 1. Our numerical simulations show that the future orbital evolution of P/2011 S1 (Gibbs) is more similar to that of the main population of Centaurs than to that of 29P/Schwassmann-Wachmann 1. The results also demonstrate that P/2011 S1 (Gibbs) is dynamically unstable and can only remain near its current orbit for roughly a thousand years.

  7. Environmental gamma radiation measurements on providence of Camaguey, Cuba

    International Nuclear Information System (INIS)

    The population exposure to those living on the Camaguey Province of Cuba, was estimated by measuring the natural gamma background. Gamma spectra of soils and measurements of absorbed dose rate in air were taken. Radiological measurements carried out with a portable ionization chamber RSS-112 at the sampled sites revealed an average outdoor absorbed dose rate of 63.6 n Gy.h 1 - due to cosmic rays and terrestrial gamma radiation. Computed dose rates obtained through the UNSCEAR(1993) dose coefficients range from 5-136 n Gy.h 1 - , with a mean value of 39.2 n Gy.h 1 - , due to natural terrestrial gamma radiation

  8. Advisory Committee for the calibration standards of ionizing radiation measurement

    International Nuclear Information System (INIS)

    The principal items of the agenda were relating to: progress reports from the Laboratories, comparison between absorbed dose calibration standards and between exposition calibration standards (national calibration standards, humidity corrections for cavity chambers, quality of the radiation to be used in the comparisons), measurements in various fields (protection, industrial radiations and very high dose rates), physical quantities and unities and comparison between activity, power and exposition measurements. In appendix, description is given of the calorimeters used by some national Laboratories for measuring absorbed doses, together with two reports of air-walled chambers

  9. Development of a Novel Solar Radiation Measuring Device

    OpenAIRE

    Samer Alsadi; Tamer Khatib; Sulafa Mallooh

    2012-01-01

    In this paper, a novel solar radiation measuring device is proposed. A solar cell, PIC controller, temperature sensors as well as a memory chip are used. The proposed device measures the solar radiation and the ambient temperature through a specific time period and then the measured data is stored on a memory chip through the PIC controller. After that the stored data can be transferred to a computer in order to be analyzed. However, a calibration of the used solar cell is done first, in orde...

  10. Present status of radiochromic techniques for nuclear radiation measurements

    International Nuclear Information System (INIS)

    Various developmental stages of radiochromic dosimetry in kGy to mGy range depending on its applications in radiation processing industries, radiological safety, medical sciences, nuclear or dirty bomb exposition and radiation accident have been described. Leuco dyes, pH sensitive dye with halogen containing compound and radiation induced solid state polymerization are the basic chemical methods presently in use for radiochromic techniques. The present status including achievements, limitations and R and D required for further improvements of accurate and precision measurements has also been highlighted. The reader system for mapping of radiation distributions in patient dosimetry and accurate measurements of personal doses in any nuclear or radiological accident scenario are also elaborated. (author)

  11. Satellite data sets for the atmospheric radiation measurement (ARM) program

    Energy Technology Data Exchange (ETDEWEB)

    Shi, L.; Bernstein, R.L. [SeaSpace Corp., San Diego, CA (United States)

    1996-04-01

    This abstract describes the type of data obtained from satellite measurements in the Atmospheric Radiation Measurement (ARM) program. The data sets have been widely used by the ARM team to derive cloud-top altitude, cloud cover, snow and ice cover, surface temperature, water vapor, and wind, vertical profiles of temperature, and continuoous observations of weather needed to track and predict severe weather.

  12. Accredited dose measurements for validation of radiation sterilized products

    DEFF Research Database (Denmark)

    Miller, A.

    1993-01-01

    for control of radiation sterilization. The accredited services include: 1. 1. Irradiation of dosimeters and test samples with cobalt-60 gamma rays. 2. 2. Irradiation of dosimeters and test samples with 10 MeV electrons. 3. 3. Issue of and measurement with calibrated dosimeters. 4. 4. Measurement...

  13. Using Radiation Pattern Measurements for Mobile Handset Performance Evaluation

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ødum; Pedersen, Gert Frølund

    2005-01-01

    The mean effective gain (MEG) is an attractive performance measure of mobile handsets, since it incorporates both directional and polarization properties of the handset and environment. In this work the MEG is computed from measured spherical radiation patterns of five different mobile handsets...

  14. Development of radiation measurement system for irradiated gemstones

    International Nuclear Information System (INIS)

    Full text: The objective of this research study was to develop the radiation measurement system for irradiated gemstones by using the automatic sample changer with hole-through NaI(Tl) detector compared to HPGe detector. The result showed that measuring time for the new system is less than 100 times HPGe detector. The accuracy of the system is 4-10%

  15. Atmospheric Radiation Measurement Climate Research Facility (ACRF) Annual Report 2008

    Energy Technology Data Exchange (ETDEWEB)

    LR Roeder

    2008-12-01

    The Importance of Clouds and Radiation for Climate Change: The Earth’s surface temperature is determined by the balance between incoming solar radiation and thermal (or infrared) radiation emitted by the Earth back to space. Changes in atmospheric composition, including greenhouse gases, clouds, and aerosols, can alter this balance and produce significant climate change. Global climate models (GCMs) are the primary tool for quantifying future climate change; however, there remain significant uncertainties in the GCM treatment of clouds, aerosol, and their effects on the Earth’s energy balance. In 1989, the U.S. Department of Energy (DOE) Office of Science created the Atmospheric Radiation Measurement (ARM) Program to address scientific uncertainties related to global climate change, with a specific focus on the crucial role of clouds and their influence on the transfer of radiation in the atmosphere. To reduce these scientific uncertainties, the ARM Program uses a unique twopronged approach: • The ARM Climate Research Facility, a scientific user facility for obtaining long-term measurements of radiative fluxes, cloud and aerosol properties, and related atmospheric characteristics in diverse climate regimes; and • The ARM Science Program, focused on the analysis of ACRF and other data to address climate science issues associated with clouds, aerosols, and radiation, and to improve GCMs. This report provides an overview of each of these components and a sample of achievements for each in fiscal year (FY) 2008.

  16. Physical measurements for quality control in industrial radiation sterilization

    International Nuclear Information System (INIS)

    The use of ionizing radiation has brought about a growing industry for the sterilization of disposable surgical equipment, medical supplies, and containers for biological specimens. For many products, irradiation has become an alternative to autoclaving or gas treatment by ethylene oxide. Over fifteen years of experience with industrial sterilization by cobalt-60 gamma radiation have shown that radiation methods provide a clear advantage over gas sterilization, in that sterilization can be performed on non-permeable sealed packages. Moreover, regulatory agencies, such as the Food and Drug Administration in the U.S.A., are reappraising the requirements for sterility assurance. For products released to the public, consideration is now being given to the use of physical dosimetry, i.e., the measurement of radiation dose by physical methods. This is based on a knowledge of the microbial burden of the product before sterilization and on the probability of killing microorganisms by a given radiation dose. Because physical dosimetry is easier to control and less complicated than biological tests, it may be considered in the future the basis for quality assurance of the sterilized product. Some of the problems associated with standardized measurement techniques in radiation sterilization include the choice of dosimetry and its calibration, as well as methods and procedures used to minimize errors due to variations in radiation flux density, source geometry with respect to the product, and environmental factors. (author)

  17. Coordinated weather balloon solar radiation measurements during a solar eclipse.

    Science.gov (United States)

    Harrison, R G; Marlton, G J; Williams, P D; Nicoll, K A

    2016-09-28

    Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse radiation measurements. For the 20 March 2015 solar eclipse, a coordinated campaign of balloon-carried solar radiation measurements was undertaken from Reading (51.44°N, 0.94°W), Lerwick (60.15°N, 1.13°W) and Reykjavik (64.13°N, 21.90°W), straddling the path of the eclipse. The balloons reached sufficient altitude at the eclipse time for eclipse-induced variations in solar radiation and solar limb darkening to be measured above cloud. Because the sensor platforms were free to swing, techniques have been evaluated to correct the measurements for their changing orientation. In the swing-averaged technique, the mean value across a set of swings was used to approximate the radiation falling on a horizontal surface; in the swing-maximum technique, the direct beam was estimated by assuming that the maximum solar radiation during a swing occurs when the photodiode sensing surface becomes normal to the direction of the solar beam. Both approaches, essentially independent, give values that agree with theoretical expectations for the eclipse-induced radiation changes.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. PMID:27550757

  18. Nonlinear wide-range measuring gamma radiation converter

    International Nuclear Information System (INIS)

    Described is a measuring gamma radiation converter with a continuous law of convertion of the initial parameter into an electric signal. The converter is intended for measuring the gamma radiation dose rate in a wide range. The operating principle of the converter is based on utilization of the nonlinear dependence of the thermomultiplier gain on the feed voltage. The detection block (DB) convert the gamma quanta flux into a sequence of current pulses of the photoelectron multiplier anode (PEM) which are fed into the direct-current amplifier (DCA) input. At the DCA output the voltage modulus decreases by the value proportional to the constant component of the current pulses of the PEM anode. The DCA output signal is represented by two voltage levels: the high level - for employees for the PEM feed, and the low one fed into the voltage-frequency converter (VFC) input. The greater the gamma radiation dose rate, the less is the output pulse recurrence frequency. The structural and principal conversion schemes are presented. The given device can serve as a wide-range measuring converters of luminous radiation of the optical range, infrared and ionizing radiations lead to the luminous radiation with the help of scintillators

  19. Radiation measurements at the ''Kosmos-900'' sattelite

    International Nuclear Information System (INIS)

    Described is a device for measuring protons and α-particles with the energies >1 MeV/nucleon in several energy ranges on ISZ ''Kosmos-900''. NS-1 spectrometer included two semiconductive detectors: conductive DCC-0-dE/dx type 37 μm thick and E-detector of DCC-Ps type 780 μm thick. Both detectors are placed in a plastic scintillator ACC (anticoinciding cap), with an optical contact with a photocathode with a photoelectronic miltiplier. Considered are preliminary experimental results, connected with proton and α-particle penetration in polar caps of magnetosphere during solar flash in 19th-22nd September, 1977 Increasing maximum of energy particle intensity was observed in approximately 12sup(h) UT on 20th September, proton and α-particle intensity approaching the maximum practically simultaneously. After approximately 12sup(h) UT counting rate drop was observed along all the channels. Noticeable asymmetry particle penetration in nothern and southern polar caps is not found in the given event

  20. An international intercomparison of absorbed dose measurements for radiation therapy

    International Nuclear Information System (INIS)

    Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)

  1. Measurement of microwave radiation from electron beam in the atmosphere

    Science.gov (United States)

    Ohta, I. S.; Akimune, H.; Fukushima, M.; Ikeda, D.; Inome, Y.; Matthews, J. N.; Ogio, S.; Sagawa, H.; Sako, T.; Shibata, T.; Yamamoto, T.

    2016-02-01

    We report the use of an electron light source (ELS) located at the Telescope Array Observatory in Utah, USA, to measure the isotropic microwave radiation from air showers. To simulate extensive air showers, the ELS emits an electron beam into the atmosphere and a parabola antenna system for the satellite communication is used to measure the microwave radiation from the electron beam. Based on this measurement, an upper limit on the intensity of a 12.5 GHz microwave radiation at 0.5 m from a 1018 eV air shower was estimated to be 3.96×10-16 W m-2 Hz-1 with a 95% confidence level.

  2. Measurement of the track structure of ionizing radiation

    International Nuclear Information System (INIS)

    After a description of the nanodosimetric measurement quantities of tracks induced by ionizing radiation the nanodosemeter operated in the PTB is described. Finally the scaling behaviour of nanodosimetry is considered. In order to test the validity of the corresponding equation ionization-cluster size distributions were measured with monoenergetic proton and alpha beams in the energy range from 0.1 to 20 MeV with propane and nitrogen as measuring gases. (HSI)

  3. Validating CERES Radiative Fluxes in the Arctic with Airborne Radiative Flux Measurements from the ARISE Campaign

    Science.gov (United States)

    Corbett, J.; Bucholtz, A.; Kato, S.; Rose, F. G.; Smith, W. L., Jr.

    2015-12-01

    The Clouds and the Earth's Radiant Energy System (CERES) instruments on board NASA's Terra, Aqua, and Soumi-NPP satellites provide the only measurements of reflected solar shortwave and emitted longwave radiative flux over the Arctic. Various methods have shown the uncertainty of CERES fluxes over sea ice to be higher than other scene types. However validation against an independent radiative flux measurement has never been attempted. We present here an attempt to better quantify the uncertainty of time-and-space averaged CERES flux measurements using airborne measurements from the Arctic Radiation - IceBridge Sea Ice Experiment (ARISE). The ARISE campaign took place during September of 2014 based out of Fairbanks, Alaska, with most of the measurements taken in the vicinity of the sea ice edge between 125°W and 150°W, and 71°N to 77°N. For six of the flights, measurements were taken in a lawnmower type pattern over either 100 x 200 km box regions at a constant altitude of >6 km, or 100 x 100 km box regions at an altitude of between 200 m to 500 m. They were designed to resemble the CERES Level 3 spatial averaging grids, and were located and timed to coincide with a high number of CERES overpasses. On board the aircraft were a set of upward and downward facing shortwave and longwave broadband radiometers (BBR), along with other instruments measuring meteorological conditions and cloud properties. We have compared the broadband radiative fluxes from BBR with those from CERES for the three days where the aircraft was flying the high altitude pattern. We use the Fu-Liou radiative transfer model to account for differences in the measurement altitude between BBR and CERES. We will present results of the comparisons between the computed fluxes and the measured longwave and shortwave radiative fluxes.

  4. RF radiation measurement on the indigenously developed solid state amplifier

    International Nuclear Information System (INIS)

    A Solid State Radio Frequency (RF) Power Amplifier module for 300 W has been developed indigenously around 350 MHz centre frequency. A shielding enclosure for the amplifier has been designed to confine the non- ionizing - radiated and conducted emissions inside the enclosure. This design has been simulated in CST microwave studio and E fields and H fields were monitored around the enclosed amplifier. These simulated results for radiated and conducted fields have been presented here. Then the enclosure has been assembled with the amplifier. For this enclosed assembly, RF radiated and conducted field emissions were monitored outside the enclosure. In this paper, measurement methodology for the radiated and conducted field has been described. These measurements have been done according to established standards for the operating frequency range. Measurements have been carried out using an omenidirectional, frequency selective electromagnetic field measuring instrument. Measured field levels for this assembly have been compared with the ICNIRP defined safety limits for personal and occupational safety hazards. This paper describes in detail, all the measurements and their analysis. (author)

  5. New devices for radiation measurement and hazard control

    International Nuclear Information System (INIS)

    Four gauges developed lately in the Department of Radioisotope Instruments and methods are presented: Dosimetric stand SD-50B for fast control of surface contamination of hands, feet, and clothing; Tc-99m isotope gamma radiation gauge for continuous measurement of Tc-99m isotope in liquid from the energy range 60-180 keV; 131I radiation source activity controller KAI-1 for fast measurement of 131I activity on automatic production line; 131I source activity controller KAI-2 for checking up if source container leaving production line contains a 131I source. (author)

  6. Measurement of radiative lifetimes and atomic transition probabilities

    International Nuclear Information System (INIS)

    Since it began in 1980, the Wisconsin Atomic Transition Probabilities (WATP) Program had measured radiative lifetimes and atomic transition probabilities for over 35 neutral and singly ionized species. Radiative lifetimes are measured using time- resolved laser-induced fluorescence of a slow atomic/ionic beam. These lifetimes are combined with branching fractions to yield absolute atomic transition probabilities for neutral and singly ionized species. The branching fractions are determined from emission spectra recorded using the 1.0 m Fourier-transform spectrometer at the National Solar Observatory at Kitt Peak, AZ. Currently the focus of the WATP Program is on the rare-earth elements, in particular Tm, Dy, and Ho.

  7. Measurement of pipe wall local thickness by combined radiation method

    International Nuclear Information System (INIS)

    Analytical dependences have been studied which describe radiation fluxes registered by the respective detectors during transmission of a collimated beam of penetrating radiation through a tube over its diameter. The dependences are necessary for engineering designs, analysis of accuracy and other characteristics of radioisotope thickness gaUges using the combined method for measurements of tube wall local thickness. Experimental investigations have been carried out with 137Cs and 60Co sources. The dependence, permitting to determine conditions providing with the preset accuracy of tube wall local thickness measurement by the combined method, has been obtained

  8. An intercomparison of detectors for measurement of background radiation

    International Nuclear Information System (INIS)

    Measurements of the background radiation were made in 1978 at 14 locations with a high-pressure ionization chamber, thermoluminiscence dosimeters (TLD's), two NaI(Tl) detectors, and a Ge(Li) spectrometer system. Simultaneous measurements with the ionization chamber and the spectrometer system provide reliable estimates of the total background exposure rate, of the individual contributors to the terrestrial exposure rate, and of the exposure rate from the secondary cosmic radiation. The TLD results agree with those of the ionization chamber. The NaI(Tl) detector results show that accurate estimates of the terrestrial exposure rate can be obtained if empirical corrections are applied. (author)

  9. Measurement of global solar radiation over Brunei Darussalam

    International Nuclear Information System (INIS)

    Measurements of global solar radiation on a horizontal surface were carried out for a period of 11 months starting from June 2001 to April 2002. The pyrano meter (Kipp and Zonen) was placed at the top of the library building of University of Brunei Darussalam, which affords optimum exposure to the instrument sensor without appreciable obstacle for incoming global radiation. The maximum and minimum monthly-averaged global irradiations of 553 W/m2 and 433 W/m2 were recorded for the months of March and October respectively. The variation of global solar radiation can be divided into two distinct groups - the low radiation values being associated with cloud and turbidity while the high values are associated with less turbid and cloudy periods

  10. Online Radiation Dose Measurement System for ATLAS experiment

    CERN Document Server

    Mandić, I; The ATLAS collaboration

    2012-01-01

    Particle detectors and readout electronics in the high energy physics experiment ATLAS at the Large Hadron Collider at CERN operate in radiation field containing photons, charged particles and neutrons. The particles in the radiation field originate from proton-proton interactions as well as from interactions of these particles with material in the experimental apparatus. In the innermost parts of ATLAS detector components will be exposed to ionizing doses exceeding 100 kGy. Energetic hadrons will also cause displacement damage in silicon equivalent to fluences of several times 10e14 1 MeV-neutrons per cm2. Such radiation doses can have severe influence on the performance of detectors. It is therefore very important to continuously monitor the accumulated doses to understand the detector performance and to correctly predict the lifetime of radiation sensitive components. Measurements of doses are important also to verify the simulations and represent a crucial input into the models used for predicting future ...

  11. Radiation protection at workplaces with increased natural radiation exposure in Greece: recording, monitoring and protection measures

    International Nuclear Information System (INIS)

    Greek Atomic Energy Commission (GAEC) is the regulatory, advisory and competent authority on radiation protection matters. It is the authority responsible for the introduction of Radiation Protection regulations and monitoring of their implementation. In 1997, within the frame of its responsibilities the Board of the GAEC appointed a task group of experts to revise and bring the present Radiation Protection Regulations into line with the Basic Safety Standards (BSS) 96/29/Euratom Directive and the 97/43/Euratom Directive (on health protection of individuals against the dangers of ionising radiation in relation to medical exposure). Concerning the Title 7. of the new European BSS Directive, which refers to the Radiation Protection at work places with increased levels of natural radiation exposure, the Radiation Protection Regulations provides that the authority responsible for recording, monitoring and introducing protection measures at these places is the GAEC. Practices where effective doses to the workers due to increased natural radiation levels, may exceed 1mSv/y, have to be specified and authorised by the GAEC. The identification procedure is ongoing

  12. Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs)

    CERN Document Server

    Lin, H W; Lacerda, P; Ip, W H; Holman, M; Protopapas, P; Chen, W P; Burgett, W S; Chambers, K C; Flewelling, H; Huber, M E; Jedicke, R; Kaiser, N; Magnier, E A; Metcalfe, N; Price, P A

    2014-01-01

    P/2011 S1 (Gibbs) is an outer solar system comet or active Centaur with a similar orbit to that of the famous 29P/Schwassmann-Wachmann 1. P/2011 S1 (Gibbs) has been observed by the Pan-STARRS 1 (PS1) sky survey from 2010 to 2012. The resulting data allow us to perform multi-color studies of the nucleus and coma of the comet. Analysis of PS1 images reveals that P/2011 S1 (Gibbs) has a small nucleus $< 4$ km radius, with colors $g_{P1}-r_{P1} = 0.5 \\pm 0.02$, $r_{P1}-i_{P1} = 0.12 \\pm 0.02$ and $i_{P1}-z_{P1} = 0.46 \\pm 0.03$. The comet remained active from 2010 to 2012, with a model-dependent mass-loss rate of $\\sim100$ kg s$^{-1}$. The mass-loss rate per unit surface area of P/2011 S1 (Gibbs) is as high as that of 29P/Schwassmann-Wachmann 1, making it one of the most active Centaurs. The mass-loss rate also varies with time from $\\sim 40$ kg s$^{-1}$ to 150 kg s$^{-1}$. Due to its rather circular orbit, we propose that P/2011 S1 (Gibbs) has 29P/Schwassmann-Wachmann 1-like outbursts that control the outgass...

  13. Measurements of Terahertz Radiation Generated using a Metallic, Corrugated Pipe

    CERN Document Server

    Bane, Karl; Antipov, Sergey; Fedurin, Mikhail; Kusche, Karl; Swinson, Christina; Xiang, Dao

    2016-01-01

    A method for producing narrow-band THz radiation proposes passing an ultra-relativistic beam through a metallic pipe with small periodic corrugations. We present results of a measurement of such an arrangement at Brookhaven's Accelerator Test Facility (ATF). Our pipe was copper and was 5 cm long; the aperture was cylindrically symmetric, with a 1 mm (radius) bore and a corrugation depth (peak-to-peak) of 60 um. In the experiment we measured both the effect on the beam of the structure wakefield and the spectral properties of the radiation excited by the beam. We began by injecting a relatively long beam compared to the wavelength of the radiation, but with short rise time, to excite the structure, and then used a downstream spectrometer to infer the radiation wavelength. This was followed by injecting a shorter bunch, and then using an interferometer (also downstream of the corrugated pipe) to measure the spectrum of the induced THz radiation. For the THz pulse we obtain and compare with calculations: the cen...

  14. Design and testing of an innovative solar radiation measurement device

    International Nuclear Information System (INIS)

    After review of studies conducted on the solar radiation measuring systems, a new innovative instrument that would help in measuring the accurate solar radiation on horizontal surfaces has been designed and tested. An advanced instrument with ease of use and high precision that would enable the user to take the readings in terms of solar intensity (W/m2) has been tested. Also, the innovative instrument can record instantaneous readings of the solar intensities as well as the averages value of the solar radiation flux during certain periods of time. The instrument based in its design on being programmed by programmable interfacing controller (PIC). Furthermore, the power supply circuit is fed by the solar energy cells and does not need an external power source.

  15. Design and testing of an innovative solar radiation measurement device

    Energy Technology Data Exchange (ETDEWEB)

    Badran, Omar; El-Tous, Yousif; Abdala, Wasfi [Faculty of Engineering Technology, Al-Balqa Applied University, Amman 11134 (Jordan); Al-Salaymeh, Ahmed [Mechanical Engineering Department, Faculty of Engineering and Technology, University of Jordan, Amman 11942 (Jordan)

    2010-08-15

    After review of studies conducted on the solar radiation measuring systems, a new innovative instrument that would help in measuring the accurate solar radiation on horizontal surfaces has been designed and tested. An advanced instrument with ease of use and high precision that would enable the user to take the readings in terms of solar intensity (W/m{sup 2}) has been tested. Also, the innovative instrument can record instantaneous readings of the solar intensities as well as the averages value of the solar radiation flux during certain periods of time. The instrument based in its design on being programmed by programmable interfacing controller (PIC). Furthermore, the power supply circuit is fed by the solar energy cells and does not need an external power source. (author)

  16. Current situation and prospect of market on the latest radiation measuring instrument

    International Nuclear Information System (INIS)

    This book deals with current situation and prospect of market on the latest radiation measuring instrument. The contents of this book are basic of technology on radiation measuring instrument with basic principle of various measuring instrument, current situation of technology and prospect of radiation measuring instrument, effect of spreading and application field of radiation measuring instrument, facility for making and research and development of radiation measuring instrument, prospect of market about radiation measuring instrument, strategy for market entry with the latest radiation measuring instrument and general prospect for the future.

  17. Short Electron Beam Bunch Characterization Through Measurement of Terahertz Radiation

    CERN Document Server

    Zhang, Shukui; Douglas, David; Shinn, Michelle D; Williams, Gwyn

    2004-01-01

    Characterization of the electron beam bunch length of the upgrade FEL at Jefferson Lab was performed by analyzing the FTIR spectra of the coherent terahertz pulses. The results are compared with autocorrelation from a scanning polarization autocorrelator that measures the optical transition radiation. The limitations of the different methods to such a characterization are presented in this paper.

  18. Mobile Handset Performance Evaluation Using Radiation Pattern Measurements

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ødum; Pedersen, Gert Frølund

    2006-01-01

    handsets, both in free space and including a human head & shoulder phantom. Different models of the environment allow a comparison of the mean effective gain obtained for realistic models based on measurements with the total radiated power and the total isotropic sensitivity. All the comparisons are based...

  19. Spectra of radioactive nuclides radiation, measured with semiconductor detectors. 2

    International Nuclear Information System (INIS)

    The second part of the atlas 'Radiation spectra of radionuclides measured with semiconductor detectors' is presented including 259 spectra of 126 alpha, beta, gamma, and X ray emitters. Some spectra of the first part of the atlas are given at another scale and sometimes for other energy ranges. The total number of investigated radionuclides amounts to 261 of which 69 are new ones

  20. Measurements of K/Π ratio in cosmic radiation

    International Nuclear Information System (INIS)

    Measurements of k/Π ratio in cosmic radiation by its half lives and its fluxes, were carried out. The kaon flux was obtained using the Cherenkov detector, and for pion flux scintillation detectors were used. The final results of K/Π ratio ∼ 0.2 was obtained. (M.C.K.)

  1. Measurement and analysis of the radiation losses in DAMAVAND Tokamak

    International Nuclear Information System (INIS)

    Radiation losses play an important role on reaching to break-even conditions in Tokamaks. In this paper the results of measurement by a bolometer in Damavand Tokamak have been presented and analyzed. Meanwhile, we have explained our future research program on the base of last modifications in the control system of the DAMAVAND.

  2. Listing of solar radiation measuring equipment and glossary

    Science.gov (United States)

    Carter, E. A.; Greenbaum, S. A.; Patel, A. M.

    1976-01-01

    An attempt is made to list and provide all available information about solar radiation measuring equipment which are being manufactured and are available on the market. The list is in tabular form and includes sensor type, response time, cost data and comments for each model. A cost code is included which shows ranges only.

  3. Gamma heating measurements in a mixed radiation field

    International Nuclear Information System (INIS)

    Gamma hearing measurements have been made in a low-Z assembly irradiated with 14-MeV neutrons and (n,n') gammas produced by a Texas Nuclear Model 9400 neutron generator. The assembly is composed of 144 magnesium sleeves (5cm x 5cm x 60cm x 3 mm thick) filled with graphite to simulate a fusion blanket test module. Heating measurements were made in the mid-line of the assembly using a proportional counter operating in the Continuously-varied Bias-voltage Acquisition (CBA) mode. The neutron induced atomic recoil signal was rejected by observing the signal rise-time differences inherent to radiations of different LET. The experiment was modelled using the one-dimensional radiation transport code ANISN/PC. The operating limits of this technique were identified by comparing measurements made at different positions in the assembly and then comparing these measurements to the calculated flux. 7 refs., 5 figs., 1 tab

  4. The resistive bolometer for radiated power measurement on EAST

    International Nuclear Information System (INIS)

    The resistive bolometer system has been successfully employed on experimental advanced superconducting tokamak for the first time to measure the radiated power of plasma. The bolometer detectors are based on 4 μm thick Pt absorbers deposited on 1.5 μm thick SiN membranes. The system consists of 3 cameras with a total of 48 channels. The detector and the system setup are described in detail. The detector calibration and typical measurement results are presented as well.

  5. Detection and spectral measurements of coherent synchrotron radiation at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, Christopher

    2010-02-15

    The operation of high-gain free-electron laser (FEL) underlies tremendous demands on high quality electron beams with high peak currents. At the Free-Electron-Laser in Hamburg (FLASH), two magnetic bunch compressors are used to compress the electron bunches longitudinally. In the bunch compressor magnets, these short electron bunches generate coherent synchrotron radiation (CSR). This CSR contains information on the longitudinal bunch profile, which is relevant for driving an FEL. In order to investigate coherent synchrotron radiation at the second bunch compressor BC3 at FLASH, a new setup behind the last dipole was installed. For the detection of coherent synchrotron radiation, which is emitted in the infrared regime, pyroelectric detectors were used. These pyroelectric detectors have been calibrated at the free-electron laser FELIX in the wavelength range from 5 {mu}m to 110 {mu}m. For characterisation of the emitted radiation, a transverse scanning device was used to measure the transverse intensity distribution. Various transmission filters were used to obtain additional information about the spectral content. In order to get spectral information with high resolution over a wide wavelength range, a rotating mirror spectrometer using reflective blazed gratings was installed. Using this spectrometer, the first spectral measurements of coherent synchrotron radiation at FLASH in a wavelength range from 10 {mu}m to 160 {mu}m were done. (orig.)

  6. Measurement of parameters in Indus-2 synchrotron radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Ghodke, A. D.; Husain, Riyasat; Kumar, Pradeep; Yadav, Surendra; Puntambekar, T. A. [Raja Ramanna Centre for Advanced Technology, 452013, Indore (India)

    2012-10-15

    The paper presents the measurement of optics parameters in Indus-2 synchrotron radiation source, which include betatron tune, beta function, dispersion function, natural chromaticity, corrected chromaticity, central RF frequency, momentum compaction factor, and linear betatron coupling. Two methods were used for beta function measurement; a conventional quadrupole scan method and a method using the fitting of the orbit response matrix. A robust Levenberg-Marquardt algorithm was used for nonlinear least square fitting of the orbit response matrix. In this paper, detailed methods for the parameter measurements are described. The measured results are discussed and compared with the theoretical values obtained using accelerator simulation code Accelerator Toolbox in MATLAB.

  7. "TNOs are Cool": A survey of the trans-Neptunian region. XI. A Herschel-PACS view of 16 Centaurs

    Science.gov (United States)

    Duffard, R.; Pinilla-Alonso, N.; Santos-Sanz, P.; Vilenius, E.; Ortiz, J. L.; Mueller, T.; Fornasier, S.; Lellouch, E.; Mommert, M.; Pal, A.; Kiss, C.; Mueller, M.; Stansberry, J.; Delsanti, A.; Peixinho, N.; Trilling, D.

    2014-04-01

    Context. Centaurs are the transitional population between trans-Neptunian objects (TNOs) and Jupiter-family comets. Their physical properties provide an insight into TNO properties, but only under restricted conditions since Centaurs are closer to the Sun and Earth. For this reason it is possible to access the smaller ones, which is more difficult to do with the TNO population. Aims: The goal of this work is to characterize a set of 16 Centaurs in terms of their size, albedo, and thermal properties. We study the correlations, for a more extended sample obtained from the literature, of diameter, albedo, orbital parameters, and spectral slopes. Methods: We performed three-band photometric observations using Herschel-PACS and used a consistent method for the data reduction and aperture photometry of this sample to obtain monochromatic flux densities at 70, 100, and 160 μm. Additionally, we used Spitzer-MIPS flux densities at 24 and 70 μm when available. We also included in our Centaur sample scattered disk objects, a dynamical family of TNOs, using results previously published by our team, and some Centaurs observed only with the Spitzer-MIPS instrument. Results: We have determined new radiometric sizes and albedos of 16 Centaurs. The first conclusion is that the albedos of Centaur objects are not correlated with their orbital parameters. Similarly, there is no correlation between diameter and orbital parameters. Most of the objects in our sample are dark (pv< 7%) and most of them are small (D< 120 km). However, there is no correlation between albedo and diameter, in particular for the group of small objects as albedo values are homogeneously distributed between 4 to 16%. The correlation with the color of the objects showed that red objects are all small (mean diameter 65 km), while the gray ones span a wide range of sizes (mean diameter 120 km). Moreover, the gray objects tend to be darker, with a mean albedo of 5.6%, compared with a mean of 8.5% (ranging from 5 to

  8. Changes in Handset Performance Measures due to Spherical Radiation Pattern Measurement Uncertainty

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ødum; Pedersen, Gert Frølund

    ), and mean effective gain (MEG) can be computed. Often this kind of measurements are made with a phantom head next to the handsets in order to simulate the influence of a real user. The measured radiation patterns are only expected to be repeatable if the same setup is used, i.e., the same phantom and...... measurement system that may introduce errors in standardized performance measurements. Radiation patterns of six handsets have been measured while they were mounted at various offsets from the reference position defined by the Cellular Telecommunications & Internet Association (CTIA) certification. The change...

  9. Measurement of TFTR D-T radiation shielding efficiency

    International Nuclear Information System (INIS)

    High power D-T fusion reactor designs presently exhibit complex geometric and material density configurations. Simulations of the radiation shielding required for safe operation and full compliance with all regulatory requirements must include sufficient margin to accommodate uncertainties in material properties and distributions, uncertainties in the final configurations, and uncertainties in approximations employing the homogenization of complex geometries. Measurements of radiation shielding efficiency performed in a realistic D-T tokamak environment can provide empirical guidance for simulating safe, efficient, and cost effective shielding systems for future high power fusion reactors. In this work, the authors present the results of initial measurements of the TFTR radiation shielding efficiency during high power D-T operations with record neutron yields. The TFTR design objective is to limit the total dose-equivalent at the nearest PPPL property lines from all radiation pathways to 10 mrem per calendar year. Compliance with this design objective over a calendar year requires measurements in the presence of typical site backgrounds of about 80 mrem per year

  10. Blast wave radiation source measurement experiments on Z

    International Nuclear Information System (INIS)

    The Dynamic Hohlraum (DH) radiation on the Z facility at Sandia National Laboratories is a bright source of radiant energy that has proven useful for High Energy Density (HED) physics experiments. To be useful for HED experiments, where computer simulations need to be compared with experimental measurements, the radiation output from a DH on Z needs to be well-known. We present in this paper a new method for measuring the delivered radiation energy deposited in an experiment, specifically, an experiment driven by a Z DH. This technique uses a blast wave produced in a SiO2 foam, which is initially super-sonic but transitions to sub-sonic, producing a shock at the transition point that is observable via radiography. The position of this shock is a sensitive measure of the radiation drive energy from the Z DH. Computer simulations have been used to design and analyze a Z foam blast wave experiment. This experiment has been shot on Z and experimental results compare favorably with the computations. (authors)

  11. Assessment and comparison of methods for solar ultraviolet radiation measurements

    International Nuclear Information System (INIS)

    In the study, the different methods to measure the solar ultraviolet radiation are compared. The methods included are spectroradiometric, erythemally weighted broadband and multi-channel measurements. The comparison of the different methods is based on a literature review and assessments of optical characteristics of the spectroradiometer Optronic 742 of the Finnish Centre for Radiation and Nuclear Safety (STUK) and of the erythemally weighted Robertson-Berger type broadband radiometers Solar Light models 500 and 501 of the Finnish Meteorological Institute and STUK. An introduction to the sources of error in solar UV measurements, to methods for radiometric characterization of UV radiometers together with methods for error reduction are presented. Reviews on experiences from world-wide UV monitoring efforts and instrumentation as well as on the results from international UV radiometer intercomparisons are also presented. (62 refs.)

  12. Assessment and comparison of methods for solar ultraviolet radiation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K.

    1995-06-01

    In the study, the different methods to measure the solar ultraviolet radiation are compared. The methods included are spectroradiometric, erythemally weighted broadband and multi-channel measurements. The comparison of the different methods is based on a literature review and assessments of optical characteristics of the spectroradiometer Optronic 742 of the Finnish Centre for Radiation and Nuclear Safety (STUK) and of the erythemally weighted Robertson-Berger type broadband radiometers Solar Light models 500 and 501 of the Finnish Meteorological Institute and STUK. An introduction to the sources of error in solar UV measurements, to methods for radiometric characterization of UV radiometers together with methods for error reduction are presented. Reviews on experiences from world-wide UV monitoring efforts and instrumentation as well as on the results from international UV radiometer intercomparisons are also presented. (62 refs.).

  13. Measurement of Radiation Belt Partcles by MDS-1 Onboard SEDA

    Science.gov (United States)

    Matsumoto, H.; Koshiishi, H.; Goka, T.

    The Space Environment Data Acquisition Equipment (SEDA) is on board the Mission Demonstration Test Satellite-1 (MDS-1) to measure the radiation environment, which was launched into geo-stationary transfer orbit (GTO) on February 4, 2002 with an apogee of about 35,700km, a perigee of about 500 km and an inclination of about 28.5 degrees. SEDA consists of the four instruments. Standard Dose Monitor monitors the electron and proton flux. Dosimeter measures the integrated radiation dose at fifty-six points of the satellite. Heavy Ion Telescope monitors the flux of heavy ions from He to Fe. Magnetometer measures the magnetic field in the magnetosphere. In this paper are described first results and comparison with the ISO standard model for the space environment

  14. Radiation measured with passive dosimeters in low Earth orbit

    Science.gov (United States)

    Zhou, D.; Semones, E.; Gaza, R.; Weyland, M.

    begin center Radiation Measured with Passive Dosimeters in Low Earth Orbit end center begin center D Zhou 1 2 E Semones 1 R Gaza 1 2 M Weyland 1 end center begin center 1 Johnson Space Center - NASA 2101 Nasa Road 1 Houston 77058 USA end center begin center 2 Universities Space Research Association 2101 Nasa Parkway Houston 77058 USA end center begin center Abstract end center The linear energy transfer LET of particles in low Earth orbit LEO is extended from sim 0 1 to sim 1000 keV mu m water The best passive dosimeters for the radiation measurement are thermoluminescence dosimeters TLDs or optically stimulated luminescence dosimeters OSLDs for low LET and CR-39 plastic nuclear track detectors PNTDs for high LET Radiation quantities fluence absorbed dose dose equivalent and quality factor were measured with the passive dosimeters composed of TLDs OSLDs and CR-39 PNTDs for STS-114 mission This paper introduces the operation principles for TLDs OSLDs and CR-39 PNTDs describes the method to combine the results measured by TLDs OSLDs and CR-39 PNTDs and presents the results measured by different dosimeters for different LET band and that combined for all LET

  15. Electron bunch length measurement at the radiation source ELBE

    International Nuclear Information System (INIS)

    In this study, measurement of electron bunch length at the ELBE Free Electron Laser (FEL) in the Forschungszentrum Dresden (FZD) is represented. Transition radiation is emitted when an electron passes the interface of two mediums of different dielectric constants. In case that the wavelength of the radiation is longer than the bunch length, coherent transition radiation (CTR) is emitted. The time profile of the CTR is a copy of the electron bunch longitudinal profile. The Martin-Puplett interferometer (MPI) is used to measure the autocorrelation function of the CTR pulse. The power spectrum and the bunch length information is obtained by Fourier transforming the measured autocorrelation function. There are different approaches for obtaining the bunch length from the MPI measurements. The data can be evaluated in the time domain as well as in the frequency domain. We can derive the longitudinal shapes of the electron bunch by analyzing the frequency information. The Measurement of the longitudinal electron bunch length is compared with the frequency domain method

  16. Recent measurements for hadrontherapy and space radiation: nuclear physics

    Science.gov (United States)

    Miller, J.

    2001-01-01

    The particles and energies commonly used for hadron therapy overlap the low end of the charge and energy range of greatest interest for space radiation applications, Z=1-26 and approximately 100-1000 MeV/nucleon. It has been known for some time that the nuclear interactions of the incident ions must be taken into account both in treatment planning and in understanding and addressing the effects of galactic cosmic ray ions on humans in space. Until relatively recently, most of the studies of nuclear fragmentation and transport in matter were driven by the interests of the nuclear physics and later, the hadron therapy communities. However, the experimental and theoretical methods and the accelerator facilities developed for use in heavy ion nuclear physics are directly applicable to radiotherapy and space radiation studies. I will briefly review relevant data taken recently at various accelerators, and discuss the implications of the measurements for radiotherapy, radiobiology and space radiation research.

  17. Problems related to radiation measurement techniques at medical institutions

    International Nuclear Information System (INIS)

    A questionnaire was sent out for the purpose of trying to grasp the existing state of radiation measurement among the medical and dental school hospitals. It was pointed out that the accuracy of measurement regarding the X-ray examination is not better than therapeutics part concerning both standard and survey measurements. The reason for this is supposed due to the unsatisfactory dependence on the low energy using in the measuring instruments. The effect of energy on measurements and the dose equivalent at a 1 cm depth were discussed. 2) The back scatter radiation to the film badge is slightly effected by the X-ray energy. It is constant when the distance between the phantom and film badge is under 3 cm and reduced over 3 cm. By adopting ICRP Pub. 26 in the near future, the dose equivalent at a 1 cm depth should be measured inorder to provide radiation protection. It is considered that the calbilation will be made using a phantom. If the caliblation is made at 3 cm distance between the phantom and film badge, the dose equivalent at 1 cm depth will be underestimated when the film badge is put at a distance of over 3 cm from the body. 3) The availability of silicon photodiode as a sensor was considered by the method in which an X-ray is directly exposured to one. The energy spectrum can be detected over the 15 - 200 keV range. It has been concluded that the usage of this sensor can calculate the dose equivalent at a 1 cm depth for lower energy radiation as using clinical examination. (author)

  18. Three Orbital Burns to Molniya Orbit Via Shuttle_Centaur G Upper Stage

    Science.gov (United States)

    Williams, Craig H.

    2015-01-01

    An unclassified analytical trajectory design, performance, and mission study was done for the 1982 to 1986 joint National Aeronautics and Space Administration (NASA)-United States Air Force (USAF) Shuttle/Centaur G upper stage development program to send performance-demanding payloads to high orbits such as Molniya using an unconventional orbit transfer. This optimized three orbital burn transfer to Molniya orbit was compared to the then-baselined two burn transfer. The results of the three dimensional trajectory optimization performed include powered phase steering data and coast phase orbital element data. Time derivatives of the orbital elements as functions of thrust components were evaluated and used to explain the optimization's solution. Vehicle performance as a function of parking orbit inclination was given. Performance and orbital element data was provided for launch windows as functions of launch time. Ground track data was given for all burns and coasts including variation within the launch window. It was found that a Centaur with fully loaded propellant tanks could be flown from a 37 deg inclination low Earth parking orbit and achieve Molniya orbit with comparable performance to the baselined transfer which started from a 57 deg inclined orbit: 9,545 versus 9,552 lb of separated spacecraft weight, respectively. There was a significant reduction in the need for propellant launch time reserve for a 1 hr window: only 78 lb for the three burn transfer versus 320 lb for the two burn transfer. Conversely, this also meant that longer launch windows over more orbital revolutions could be done for the same amount of propellant reserve. There was no practical difference in ground tracking station or airborne assets needed to secure telemetric data, even though the geometric locations of the burns varied considerably. There was a significant adverse increase in total mission elapsed time for the three versus two burn transfer (12 vs. 1-1/4 hr), but could be

  19. Three Orbital Burns to Molniya Orbit via Shuttle Centaur G Upper Stage

    Science.gov (United States)

    Williams, Craig H.

    2014-01-01

    An unclassified analytical trajectory design, performance, and mission study was done for the 1982-86 joint NASA-USAF Shuttle/Centaur G upper stage development program to send performance-demanding payloads to high orbits such as Molniya using an unconventional orbit transfer. This optimized three orbital burn transfer to Molniya orbit was compared to the then-baselined two burn transfer. The results of the three dimensional trajectory optimization performed include powered phase steering data and coast phase orbital element data. Time derivatives of the orbital elements as functions of thrust components were evaluated and used to explain the optimization's solution. Vehicle performance as a function of parking orbit inclination was given. Performance and orbital element data was provided for launch windows as functions of launch time. Ground track data was given for all burns and coasts including variation within the launch window. It was found that a Centaur with fully loaded propellant tanks could be flown from a 37deg inclination low Earth parking orbit and achieve Molniya orbit with comparable performance to the baselined transfer which started from a 57deg inclined orbit: 9,545 lb vs. 9,552 lb of separated spacecraft weight respectively. There was a significant reduction in the need for propellant launch time reserve for a one hour window: only 78 lb for the three burn transfer vs. 320 lb for the two burn transfer. Conversely, this also meant that longer launch windows over more orbital revolutions could be done for the same amount of propellant reserve. There was no practical difference in ground tracking station or airborne assets needed to secure telemetric data, even though the geometric locations of the burns varied considerably. There was a significant adverse increase in total mission elapsed time for the three vs. two burn transfer (12 vs. 11/4 hrs), but could be accommodated by modest modifications to Centaur systems. Future applications were

  20. Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs)

    Energy Technology Data Exchange (ETDEWEB)

    Lin, H. W.; Ip, W. H.; Chen, W. P. [Institute of Astronomy, National Central University, Taoyuan 32001, Taiwan (China); Chen, Y. T. [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China); Lacerda, P. [Astrophysics Research Centre, School of Mathematics and Physics, Queens University Belfast, Belfast BT7 1NN (United Kingdom); Holman, M.; Protopapas, P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Burgett, W. S.; Chambers, K. C.; Flewelling, H.; Huber, M. E.; Jedicke, R.; Kaiser, N.; Magnier, E. A.; Metcalfe, N. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Price, P. A., E-mail: edlin@gm.astro.ncu.edu.tw [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2014-05-01

    P/2011 S1 (Gibbs) is an outer solar system comet or active Centaur with a similar orbit to that of the famous 29P/Schwassmann-Wachmann 1. P/2011 S1 (Gibbs) has been observed by the Pan-STARRS 1 (PS1) sky survey from 2010 to 2012. The resulting data allow us to perform multi-color studies of the nucleus and coma of the comet. Analysis of PS1 images reveals that P/2011 S1 (Gibbs) has a small nucleus <4 km radius, with colors g {sub P1} – r {sub P1} = 0.5 ± 0.02, r {sub P1} – i {sub P1} = 0.12 ± 0.02, and i {sub P1} – z {sub P1} = 0.46 ± 0.03. The comet remained active from 2010 to 2012, with a model-dependent mass-loss rate of ∼100 kg s{sup –1}. The mass-loss rate per unit surface area of P/2011 S1 (Gibbs) is as high as that of 29P/Schwassmann-Wachmann 1, making it one of the most active Centaurs. The mass-loss rate also varies with time from ∼40 kg s{sup –1} to 150 kg s{sup –1}. Due to its rather circular orbit, we propose that P/2011 S1 (Gibbs) has 29P/Schwassmann-Wachmann 1-like outbursts that control the outgassing rate. The results indicate that it may have a similar surface composition to that of 29P/Schwassmann-Wachmann 1. Our numerical simulations show that the future orbital evolution of P/2011 S1 (Gibbs) is more similar to that of the main population of Centaurs than to that of 29P/Schwassmann-Wachmann 1. The results also demonstrate that P/2011 S1 (Gibbs) is dynamically unstable and can only remain near its current orbit for roughly a thousand years.

  1. Direct measurements of radiative capture reactions with DRAGON

    Science.gov (United States)

    Christian, Gregory

    2015-10-01

    Direct measurements of radiative proton and alpha capture reactions are crucial for understanding nucleosynthesis in a variety of astrophysical environments, including classical novae, supernovae, X-Ray bursts, and quiescent stellar burning. Often the most important reactions have very low cross sections or involve unstable targets, making laboratory measurements extremely challenging. The detector of recoils and gammas of nuclear reactions (DRAGON) at TRIUMF is a recoil mass separator designed to measure radiative capture reactions in inverse kinematics, with beam suppression factors as high as 1016. When combined with the intense radioactive beams available at the ISAC-I facility, DRAGON's capabilities are unique and world-leading. In this talk, I will give a brief technical overview of DRAGON before presenting results from recent experiments. Some highlights include the first-ever direct measurement of 38K(p , γ) 39Ca, a crucial reaction for determining the endpoint of nova nucleosynthesis, and measurements of 76Se(α , γ) 80Kr. The latter measurements determine the rate of the reverse reaction, 80Kr(γ , α) 76Se, an important waiting point in the synthesis of the p-nuclei. I will also discuss future (and ongoing) developments at DRAGON, including the commissioning of a new chamber for high-precision elastic scattering measurements and plans to determine the 330 keV resonance strength in 18F(p , γ) 19Ne via measurements of 15O(α , γ) 19Ne and 15O + α elastic scattering.

  2. Effective aerosol optical depth from pyranometer measurements of surface solar radiation (global radiation at Thessaloniki, Greece

    Directory of Open Access Journals (Sweden)

    A. V. Lindfors

    2013-04-01

    Full Text Available Pyranometer measurements of the solar surface radiation (SSR are available at many locations worldwide, often as long time series covering several decades into the past. These data constitute a potential source of information on the atmospheric aerosol load. Here, we present a method for estimating the aerosol optical depth (AOD using pyranometer measurements of the SSR together with total water vapor column information. The method, which is based on radiative transfer simulations, was developed and tested using recent data from Thessaloniki, Greece. The effective AOD calculated using this method was found to agree well with co-located AERONET measurements, exhibiting a correlation coefficient of 0.9 with 2/3 of the data found within ±20% or ±0.05 of the AERONET AOD. This is similar to the performance of current satellite aerosol methods. Differences in the AOD as compared to AERONET can be explained by variations in the aerosol properties of the atmosphere that are not accounted for in the idealized settings used in the radiative transfer simulations, such as variations in the single scattering albedo and Ångström exponent. Furthermore, the method is sensitive to calibration offsets between the radiative transfer simulations and the pyranometer SSR. The method provides an opportunity of extending our knowledge of the atmospheric aerosol load to locations and times not covered by dedicated aerosol measurements.

  3. Effective aerosol optical depth from pyranometer measurements of surface solar radiation (global radiation at Thessaloniki, Greece

    Directory of Open Access Journals (Sweden)

    A. V. Lindfors

    2012-12-01

    Full Text Available Pyranometer measurements of the solar surface radiation (SSR are available at many locations worldwide, often as long time series covering several decades into the past. These data constitute a potential source of information on the atmospheric aerosol load. Here, we present a method for estimating the aerosol optical depth (AOD using pyranometer measurements of the SSR together with total water vapor column information. The method, which is based on radiative transfer simulations, was developed and tested using recent data from Thessaloniki, Greece. The effective AOD calculated using this method was found to agree well with co-located AERONET measurements, exhibiting a correlation coefficient of 0.9 with 2/3 of the data found within ±20% or ±0.05 of the AERONET AOD. This is similar to the performance of current satellite aerosol methods. Differences in the AOD as compared to AERONET can be explained by variations in the aerosol properties of the atmosphere that are not accounted for in the idealized settings used in the radiative transfer simulations, such as variations in the single scattering albedo and Ångström exponent. Furthermore, the method is sensitive to calibration offsets between the radiative transfer simulations and the pyranometer SSR. The method provides an opportunity of extending our knowledge of the atmospheric aerosol load to locations and times not covered by dedicated aerosol measurements.

  4. A new system for measurement of the space radiation

    International Nuclear Information System (INIS)

    The space radiation mainly consists of heavy charged particles (protons and heavier particles). Due to this fact its effective dose significantly differs from the physical dose. The recently used measuring equipment is not fully suitable to measure both quantities simultaneously. The combined device for measurement of mentioned values consists of an on board thermoluminescent dosimeter reader and a three axis silicon telescope as a linear energy transfer spectrometer. The paper deals with the main characteristics of the new system. This system can be applied for dosimetry of air-crew as well. (authors)

  5. A new system for the measurement of the space radiation

    International Nuclear Information System (INIS)

    Radiation from space mainly consists of charged heavy particles (protons and heavier particles). Due to this fact, the effective dose significantly differs from the physical dose. Current measuring equipment is not fully suitable to measure both of the quantities simultaneously. A combined device for measurement of the mentioned values consists of an on-board thermoluminescence dosimeter reader and a three-axis silicon detector linear energy transfer spectrometer. This paper deals with the main characteristic of the new system. This system can be, applied for dosimetry of air crew as well. (authors)

  6. Health physics measurements of laser radiation: Experience and competence wanted

    International Nuclear Information System (INIS)

    Measurement of the parameters required for an analysis of hazards involved is a complex task in terms of measuring techniques and calibration, and a costly procedure at that. Although part of the evaluation work can be done with the support of computers, evaluation and interpretation of measured information requires the experience and competence of the human expert. It is to be hoped that the computer industry will soon have developed turn-key solutions of universal applicability for analytical tasks of this kind, so that in the near future determination of the source terms, especially for LED or IRED radiation, will be an easy task. (orig./CB)

  7. Measurements of Compton Scattered Transition Radiation at High Lorentz Factors

    CERN Document Server

    Case, G L; Cherry, M L; Isbert, J; Mitchell, J W; Patterson, D; Case, Gary L.; Cherry, Michael L.; Isbert, Joachim; Mitchell, John W.; Patterson, Donald

    2004-01-01

    X-ray transition radiation can be used to measure the Lorentz factor of relativistic particles. Standard transition radiation detectors (TRDs) typically incorporate thin plastic foil radiators and gas-filled x-ray detectors, and are sensitive up to \\gamma ~ 10^4. To reach higher Lorentz factors (up to \\gamma ~ 10^5), thicker, denser radiators can be used, which consequently produce x-rays of harder energies (>100 keV). At these energies, scintillator detectors are more efficient in detecting the hard x-rays, and Compton scattering of the x-rays out of the path of the particle becomes an important effect. The Compton scattering can be utilized to separate the transition radiation from the ionization background spatially. The use of conducting metal foils is predicted to yield enhanced signals compared to standard nonconducting plastic foils of the same dimensions. We have designed and built a Compton Scatter TRD optimized for high Lorentz factors and exposed it to high energy electrons at the CERN SPS. We pres...

  8. Development of radiation protection and measurement technology -A study on the radiation and environmental safety-

    International Nuclear Information System (INIS)

    Reference radiation fields which can meet the national and international standard and criteria such as the ANSI N13.11 have been designed, produced and evaluated to maintain the national traceability and reliability of the radiation measurement and to provide precise calibration of the various radiation measuring instruments as well as standard irradiation of the personal dosimeters for the performance evaluation. Existing dose calculation algorithm has been improved to correctly evaluate the shallow dose from the β(Ti-204) + γ(Cs-137) mixed radiation exposure by applying the TLD response correction function newly derived in this study. A mathematical algorithm to calculate the internal dose from inhalation of the uranium isotopes has been developed on the basis of the ICRP-30 respiratory tract model. Detailed performance analysis of the KAERI lung counter has been carried out to participate in the intercomparison of lung dosimetry. A preliminary and basic study on the quantitative method of optimal dose reduction based on the ALARA concept has been performed to technically support and strengthen the national radiation protection infrastructure. (Author)

  9. A novel multipoint measuring system of photosynthetically active radiation

    International Nuclear Information System (INIS)

    A novel multipoint measuring system of photosynthetically active radiation (PAR) has been designed. It is used as a component of a field measurement system of photosynthesis. The system consists of a multichannel fiberoptic sensor, Intel 486-based microcomputer (PC) with software for control and analysis and interface electronics. The fiberoptic sensor comprises 800 measuring points which are arranged in a regular grid on a plane. This grid is attached to a cuvette to observe the spatial and temporal distribution of PAR falling on the needles along with simultaneous measurements of CO2 exchange. PAR is registered through a fiberoptic bundle using a charge coupled device (CCD) sensor. The system has been in operation between July and October 1996 within a Scots pine canopy. The results demonstrate that the obtained regression between the photosynthetic rate estimated with the multipoint PAR measuring system and the measured CO2 exchange rate is as tight within a canopy as in unshaded conditions. (author)

  10. Investigation of bias radiation effect on PV cell measurement

    Science.gov (United States)

    Huang, Xuebo; Quan, Chenggen; Chan, Joanne; Ng, Patrick

    2013-06-01

    Photovoltaic (PV) cells are photo-electrical devices that convert light energy directly into electricity through the photovoltaic effect. PV cell assemblies are used to make solar modules employed in a variety of ways ranging from space applications to domestic energy consumption. Characterisation and performance testing of PV cells are critical to the development of PV technologies and growth of the solar industry. As new solar products are being developed, its energy conversion efficiency and other critical parameters must be accurately measured and tested against globally recognised metrological standards. The differential spectral responsivity (DSR) measurement is one of the primary methods for calibrating reference PV cells. This is done by calculating its spectral responsivities through measuring the AC short-circuit current produced by a PV cell under a modulated monochromatic radiation and different levels of steady-state broadband bias light radiation. It is observed that different types of bias light source will produce different signal-to-noise levels and significantly influence measurement accuracy. This paper aims to investigate the noise sources caused by different types of bias light sources (e.g. xenon arc and tungsten-halogen lamps) and the relevant measurement uncertainties so as to propose a guideline for selection of bias light source which can improve the signal-to-noise level and measurement uncertainty. The DSRs of the PV cells are measured using a commercial DSR measurement system under different levels of bias radiation from 0 to 1 kWm-2. The data analysis and uncertainty evaluation are presented in this paper using experimental data and mathematical tools.

  11. Measurement of Radiation - Light Field Congruence using a Photodiode Array

    Science.gov (United States)

    Balderson, Michael J.

    Improved treatment techniques in radiation therapy provide incentive to reduce treatment margins, thereby increasing the necessity for more accurate geometrical setup of the linear accelerator and accompanying components. In this thesis, we describe the development of a novel device that enables precise and automated measurement of radiation-light field congruence of medical linear accelerators for the purpose of improving setup accuracy, and standardizing repeated quality control activities. The device consists of a silicon photodiode array, an evaluation board, a data acquisition card, and a laptop. Using the device, we show that the radiation-light field congruence for both 6 and 15 MV beams is within 2 mm on a Varian Clinac 21 EX medical linear accelerator. Because measurements are automated, ambiguities resulting from observer variability are removed, greatly improving the reproducibility of measurements over time and across observers. We expect the device to be useful in providing consistent measurements on linear accelerators used for stereotactic radiosurgery, during the commissioning of new linear accelerators, and as an alternative to film or other commercially available devices for performing monthly or annual quality control checks.

  12. Measurements of radiated elastic wave energy from dynamic tensile cracks

    Science.gov (United States)

    Boler, Frances M.

    1990-01-01

    The role of fracture-velocity, microstructure, and fracture-energy barriers in elastic wave radiation during a dynamic fracture was investigated in experiments in which dynamic tensile cracks of two fracture cofigurations of double cantilever beam geometry were propagating in glass samples. The first, referred to as primary fracture, consisted of fractures of intact glass specimens; the second configuration, referred to as secondary fracture, consisted of a refracture of primary fracture specimens which were rebonded with an intermittent pattern of adhesive to produce variations in fracture surface energy along the crack path. For primary fracture cases, measurable elastic waves were generated in 31 percent of the 16 fracture events observed; the condition for radiation of measurable waves appears to be a local abrupt change in the fracture path direction, such as occurs when the fracture intersects a surface flaw. For secondary fractures, 100 percent of events showed measurable elastic waves; in these fractures, the ratio of radiated elastic wave energy in the measured component to fracture surface energy was 10 times greater than for primary fracture.

  13. Measurement of the energy specta from gamma radiation fields

    International Nuclear Information System (INIS)

    The ability to measure the energy spectrum of a gamma radiation field is very beneficial for radiation protection considerations. Identifying the actual components and processes that make up the field is essential for efficient and cost effective shield design. This report discusses the use of a handheld intrinsic germanium spectrometer in measuring the energy spectra of the gamma radiation fields generated during the operation of the Sandia Pulsed Reactors. These reactors are bare reactor assemblies operated in a concrete shield building at Sandia National Laboratories. The results are to be incorporated in the design of a new shield building to house the newest member of the family of SPR reactors. The detector interfaces to a computerized MCA through a 500 foot cable package, and the computer/MCA is mounted in a trailer allowing outdoor and mobile applications of the system. The detector is capable of being operated in fields up to about 5 mR/hr gamma without collimation, and collimation techniques are being studied to allow higher radiation levels. The techniques developed allow qualitative and quantitative analysis of the energy spectra of the field. The major contributing factors to the field can be identified, allowing one to selectively reduce or shield against these factors more effectively. Other uses for the system are being explored, such as evaluating portable detector calibration procedures, and these will also be discussed

  14. Radiation induced mitochondrial biogenesis: limitations of metabolic viability based assays in measuring radiation induced cell death

    International Nuclear Information System (INIS)

    Many techniques based on metabolic viability of cells employing MTT and MTS assay are being widely used to measure the radiation and chemotherapeutics induced cell death, because of their high throughput capability. These assays are based on mitochondrial potential of cells to convert the substrate in to measurable products and remain dependent on this notion that all the cells untreated and treated will have equal mitochondrial content and metabolic potential. However, it is increasingly becoming clear that treatment induced changes in both mitochondrial content and metabolism can influence the metabolic viability of cells and radiation is a potential mitochondrial biogenesis inducer. Therefore, we tested if metabolic viability based assays are true measure of radiation induced cell death using the widely used cell lines like RAW264.7, HEK293, NIH3T3, J774.1, BMG-1, MDAMB231, MCF-7, A549 and HeLa. Cells were irradiated with gamma rays (60Co) and enumerated cell numbers (by hemocytometer) and metabolic viability using MTT assay at 24 and 48 hours after exposure. At all the absorbed doses (0-5 Gy), the extent of reduction in cell number was found to be larger than the decrease in formazan formation in all the cell lines tested. Further, this difference in the cell number and formazan formation varied significantly among the cell lines. To test if the increased formazan formation is due to increased mitochondrial content per cell, we analyzed the radiation induced mitochondrial biogenesis using mitochondria specific dye mitotracker red and found a 1.5 to 2 fold increase in mitochondrial content. These findings suggest that radiation induces mitochondrial biogenesis that enhances the metabolic potential leading to increased formazan formation. Therefore, conclusions drawn on radiation induced cytotoxicity based on metabolic viability assays are likely to be erroneous as it may not correlate with growth inhibition and/or loss of clonogenic survival. (author)

  15. Measurements of nonionizing radiation emitted from microwave oven

    International Nuclear Information System (INIS)

    There is an increase in the usage of microwave oven which is used electromagnetic radiation in the microwave range, which believed to be harmful to human health. The measurements were taken at distance of range(0-100) cm from the microwave oven. The study concluded that the risk possibility of the radiation increases at high mode. We measured the power density, magnetic field and signal strength of microwave oven using the SPECTRAN high frequency (HF-6080) detector. The experimental results of power density were found to be (3.78-208000) nW/m2 and magnetic field is (0.001-0.744) mA/m. These values are less than the exposure limits recommended. (author)

  16. Airborne gamma radiation soil moisture measurements over short flight lines

    Science.gov (United States)

    Peck, Eugene L.; Carrol, Thomas R.; Lipinski, Daniel M.

    1990-01-01

    Results are presented on airborne gamma radiation measurements of soil moisture condition, carried out along short flight lines as part of the First International Satellite Land Surface Climatology Project Field Experiment (FIFE). Data were collected over an area in Kansas during the summers of 1987 and 1989. The airborne surveys, together with ground measurements, provide the most comprehensive set of airborne and ground truth data available in the U.S. for calibrating and evaluating airborne gamma flight lines. Analysis showed that, using standard National Weather Service weights for the K, Tl, and Gc radiation windows, the airborne soil moisture estimates for the FIFE lines had a root mean square error of no greater than 3.0 percent soil moisture. The soil moisture estimates for sections having acquisition time of at least 15 sec were found to be reliable.

  17. Measurement and assessment of doses from external radiations required for revised radiation protection regulations

    International Nuclear Information System (INIS)

    Radiation protection regulations based on the 1990 recommendations of ICRP have been revised and will take effect from Apr., 2001. The major changes concerning on the measurement and assessment of doses from external radiations are as follows. (1) Personal dose equivalent and ambient dose equivalent stated in ICRP Publication 74 are introduced as quantities to be measured with personal dosimeters and survey instruments, respectively. (2) For multiple dosimetry for workers, the compartment weighting factors used for a realistic assessment of effective dose are markedly changed. In advance of the introduction of the new radiation protection regulations, the impacts on workplace and personal monitoring for external radiations by these revisions were investigated. The following results were obtained. (1) A new ambient dose equivalent to neutrons is higher with a factor of 1.2 than the old one for moderated fission neutron spectra. Therefore, neutron dose equivalent monitors for workplace monitoring at MOX fuel for facilities should be recalibrated for measurement of the new ambient dose equivalent. (2) Annual effective doses of workers were estimated by applying new calibration factors to readings of personal dosimeters, worn by workers. Differences between effective doses and effective dose equivalents are small for workers engaged in the fabrication process of MOX fuel. (author)

  18. Absolute Bunch Length Measurements by Incoherent Radiation Fluctuation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sannibale, F.; /LBL, Berkeley; Stupakov, G.V.; /SLAC; Zolotorev, M.S.; /LBL, Berkeley; Filippetto, D.; /INFN, Rome; Jagerhofer, L.; /Vienna, Tech. U.

    2009-12-09

    By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and successfully tested a simple scheme based on this principle that allows for the absolute measurement of the rms bunch length. A description of the method and the experimental results are presented.

  19. Radiation exposure in nuclear medicine: real-time measurement

    OpenAIRE

    Sylvain Iara; Bok Bernard

    2002-01-01

    French regulations have introduced the use of electronic dosimeters for personal monitoring of workers. In order to evaluate the exposure from diagnostic procedures to nuclear medicine staff, individual whole-body doses were measured daily with electronic (digital) personal dosimeters during 20 consecutive weeks and correlated with the work load of each day. Personal doses remained always below 20 µSv/d under normal working conditions. Radiation exposure levels were highest to tech staff, nur...

  20. Radiation measurements in the reactors G 2 and G 3

    International Nuclear Information System (INIS)

    The results are given of numerous radiation measurements: - for the various working sites - for the various zones (circuit room,etc) - during the discharging operations - far various active materials (CO2, plugs etc). They show that in general the protection has been suitably designed and that the majority of radio-protection problems are due to the elements activated in the pile and transported outside the vessel. (authors)

  1. Measurement of refracting index of wood for microwave radiation

    International Nuclear Information System (INIS)

    The refracting index of wood depends strongly on its moisture content. In this work we present the results of measurements of the index using electromagnetic radiation with a frequency of 9.35 GHz that corresponds to microwaves. The relationship between the wood moisture content (MC) and the index in some softwood and hardwood species could be the basis for a determination method of moisture content, covering a wide range of values

  2. Determining meson radiative widths from Primakoff-effect measurements

    International Nuclear Information System (INIS)

    We suggest that the measurement of vector-meson radiation decays V → Pγ in the Primakoff-effect experiments on nuclei should be reanalyzed including isovector hadronic exchange. Its inclusion invalidates the assumption, made in data analyses, of A independence of the strength of the strong-production amplitude and could well remove the disagreement between theory and experiment for GAMMA (rho → πγ) and GAMMA

  3. Characteristics of imaging plate and its applications to radiation measurement

    International Nuclear Information System (INIS)

    Since Imaging Plate has very high sensitivity of ∼103 times to conventional x-ray films, large dynamic range ∼105 and large area up to 35cmx43cm, it has many applicational fields which are still expanding. Distributions of radioactivity on granite surface and slite radioactive-contamination in a hot laboratory can be easily measured. Many times successive read-out method can give the informations on the radiation kind and energy. (author)

  4. Errors in measuring absorbed radiation and computing crop radiation use efficiency

    International Nuclear Information System (INIS)

    Radiation use efficiency (RUE) is often a crucial component of crop growth models that relate dry matter production to energy received by the crop. RUE is a ratio that has units g J-1, if defined as phytomass per unit of energy received, and units J J-1, if defined as the energy content of phytomass per unit of energy received. Both the numerator and denominator in computation of RUE can vary with experimental assumptions and methodologies. The objectives of this study were to examine the effect that different methods of measuring the numerator and denominator have on the RUE of corn (Zea mays L.) and to illustrate this variation with experimental data. Computational methods examined included (i) direct measurements of the fraction of photosynthetically active radiation absorbed (fA), (ii) estimates of fA derived from leaf area index (LAI), and (iii) estimates of fA derived from spectral vegetation indices. Direct measurements of absorbed PAR from planting to physiological maturity of corn were consistently greater than the indirect estimates based on green LAI or the spectral vegetation indices. Consequently, the RUE calculated using directly measured absorbed PAR was lower than the RUE calculated using the indirect measures of absorbed PAR. For crops that contain senesced vegetation, green LAI and the spectral vegetation indices provide appropriate estimates of the fraction of PAR absorbed by a crop canopy and, thus, accurate estimates of crop radiation use efficiency

  5. Space radiation measurements on-board ISS - The DOSMAP experiment

    International Nuclear Information System (INIS)

    The experiment 'Dosimetric Mapping' conducted as part of the science program of NASA's Human Research Facility (HRF) between March and August 2001 was designed to measure integrated total absorbed doses (ionising radiation and neutrons), heavy ion fluxes and its energy, mass and linear energy transfer (LET) spectra, time-dependent count rates of charged particles and their corresponding dose rates at different locations inside the US Lab at the International Space Station. Owing to the variety of particles and energies, a dosimetry package consisting of thermoluminescence dosemeter (TLD) chips and nuclear track detectors with and without converters (NTDPs), a silicon dosimetry telescope (DOSTEL), four mobile silicon detector units (MDUs) and a TLD reader unit (PILLE) with 12 TLD bulbs as dosemeters was used. Dose rates of the ionising part of the radiation field measured with TLD bulbs applying the PILLE readout system at different locations varied between 153 and 231 μGy d-1. The dose rate received by the active devices fits excellent to the TLD measurements and is significantly lower compared with measurements for the Shuttle (STS) to MIR missions. The comparison of the absorbed doses from passive and active devices showed an agreement within ±10%. The DOSTEL measurements in the HRF location yielded a mean dose equivalent rate of 535 μSv d-1. DOSTEL measurements were also obtained during the Solar Particle Event on 15 April 2001. (authors)

  6. Development of prototype fiber optics dosimeter for remote radiation measurements

    International Nuclear Information System (INIS)

    Optical fiber dosimetry has been studied as an emerging method of monitoring radiation remotely in difficult to access and hazardous areas and is suitable for use in confined environments that may be inaccessible using existing dosimeters. Being light weight and non intrusive, optical fibers provide several advantages in the field of dosimetry like resistant to electromagnetic interferences. An extrinsic architecture, where the radiation-sensing component is spliced or coupled to an optical fiber, is employed in this work. A prototype single channel fiber optic based remote radiation measurement system with BaFBr:Eu sensor, which has a wide linear dose response, is developed at Radiological Safety Division, IGCAR. High sensitive BaFBr:Eu2+ storage phosphor of 10 mm dia and 4 mm thickness has been successfully synthesized using high temperature solid state diffusion route in a reducing atmosphere. Optical characteristics of the BaFBr:Eu pellet were studied by taking Photoluminescence (PL) and Photo stimulated luminescence (PSL) measurements. PL emission wavelength is measured to be 390 nm. The BaFBr:Eu is irradiated for various absorbed doses in a gamma chamber at 213 Gy/hr using 60Co standard source (BRIT make) available at RSD, IGCAR

  7. Characterization of a radiation detector for aircraft measurements

    Energy Technology Data Exchange (ETDEWEB)

    Holanda M, L. de; Federico, C. A.; Caldas, L. V. E., E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares, Av. Lineu Prestes 2242, Cidade Universitaria, CEP 05508-000, Sao Paulo (Brazil)

    2014-08-15

    Air crews, as pilots and flight attendants, are subjected to cosmic ray doses which can be higher than the average doses on workers from the nuclear industry. The diversity of particles of high energies present in the radiation field on board of air crafts turns the determination of the incident dose difficult, and requires special care regarding dosimetric systems to be used in this kind of radiation field. The Brazilian Air Force, through its Institute for Advanced Studies (Instituto de Estudos Avancados, IEAv/DCTA) in conjunction with the Institute of Energetic and Nuclear Research (Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP) are working on this subject since 2008. A prototype of a radiation detector for aircraft measurements was previously built and tested in flight and laboratory conditions. The detector is able of measuring a quantity known as absorbed dose (using passive dosimeters), which will subsequently be correlated to the ambient dose equivalent and the effective dose received by air crews. In this context, a theoretical approach through Monte Carlo simulations with the computational codes MCNP5 and MCNPX was used to model and characterize the detector response at such experimental conditions. This work presents the preliminary results of the computational modeling, with special emphasis on the comparison between the absorbed doses measured and simulated, and its relationship with the ambient dose equivalent and the effective dose for this detector. (author)

  8. Measuring element for detection and dose measurement of gamma radiation and neutrons and manufacturing method for the measuring element

    International Nuclear Information System (INIS)

    The measuring element consists of a bubble-free glass composed on the basis of metaphosphate material. The detection of the γ-radiation takes place through the photoluminescence of the element, and detection of the neutrons by means of resulting β particles producing Cerenkov radiation in the radioluminescence material, that can be measured. For this purpose in addition to Ag the glass contains As as a second excitable element. (DG)

  9. Radiation measurements on the flight of IML-2.

    Science.gov (United States)

    Badhwar, G D; Dudkin, V; Doke, T; Atwell, W

    1998-01-01

    The second flight of the International Microgravity Laboratory (IML-2) on Space Shuttle flight STS-65 provided a unique opportunity for the intercomparison of a wide variety of radiation measurement techniques. Although this was not a coordinated or planned campaign, by sheer chance, a number of space radiation experiments from several countries were flown on this mission. There were active radiation measuring instruments from Japan and US, and passive detectors from US, Russia, Japan, and Germany. These detectors were distributed throughout the Space Shuttle volume: payload bay, middeck, flight deck, and Spacelab. STS-65 was launched on July 8, 1994, in a 28.45 degrees x 306 km orbit for a duration of 14 d 17 hr and 55 min. The crew doses varied from 0.935 mGy to 1.235 mGy. A factor of two variation was observed between various passive detectors mounted inside the habitable Shuttle volume. There is reasonable agreement between the galactic cosmic ray dose, dose equivalent and LET spectra measured by the tissue equivalent proportional counter flown in the payload bay with model calculations. There are significant differences in the measurements of LET spectra measured by different groups. The neutron spectrum in the 1-20 MeV region was measured. Using fluence-dose conversion factors, the neutron dose and dose equivalent rates were 11 +/- 2.7 microGy/day and 95 +/- 23.5 microSv/day respectively. The average east-west asymmetry of trapped proton (>3OMeV) and (>60 MeV) dose rate was 3.3 and 1.9 respectively. PMID:11542776

  10. Atmospheric radiation measurement program facilities newsletter, June 2002.; TOPICAL

    International Nuclear Information System (INIS)

    ARM Intensive Operational Period Scheduled to Validate New NASA Satellite-Beginning in July, all three ARM sites (Southern Great Plains[SGP], North Slope of Alaska, and Tropical Western Pacific; Figure 1) will participate in the AIRS Validation IOP. This three-month intensive operational period (IOP) will validate data collected by the satellite-based Atmospheric Infrared Sounder (AIRS) recently launched into space. On May 4, the National Aeronautics and Space Administration (NASA) launched Aqua, the second spacecraft in the Earth Observing System (EOS) series. The EOS satellites monitor Earth systems including land surfaces, oceans, the atmosphere, and ice cover. The first EOS satellite, named Terra, was launched in December 1999. The second EOS satellite is named Aqua because its primary focus is understanding Earth's water cycle through observation of atmospheric moisture, clouds, temperature, ocean surface, precipitation, and soil moisture. One of the instruments aboard Aqua is the AIRS, built by the Jet Propulsion Laboratory, a NASA agency. The AIRS Validation IOP complements the ARM mission to improve understanding of the interactions of clouds and atmospheric moisture with solar radiation and their influence on weather and climate. In support of satellite validation IOP, ARM will launch dedicated radiosondes at all three ARM sites while the Aqua satellite with the AIRS instrument is orbiting overhead. These radiosonde launches will occur 45 minutes and 5 minutes before selected satellite overpasses. In addition, visiting scientists from the Jet Propulsion Laboratory will launch special radiosondes to measure ozone and humidity over the SGP site. All launches will generate ground-truth data to validate satellite data collected simultaneously. Data gathered daily by ARM meteorological and solar radiation instruments will complete the validation data sets. Data from Aqua-based instruments, including AIRS, will aid in weather forecasting, climate modeling, and

  11. Therapy palliative with 223Ra without special radiation protection measures?

    International Nuclear Information System (INIS)

    For nearly 2 years now as a therapy of the castration resistant prostata carcinoma a nuclide therapy with 223Ra-Dichloride (trade-mark Xofigo) is applied. Xofigo is applied by a medical specialist for nuclear medicine altogether 6 times in a monthly distance. The activity used in each case is according to the body weight (50 kBq/kg BW). This therapy is licensed by the supervisory authorities of the German federal countries as an ambulant therapy. Special radiation protection measures are only required when exceeding a given number of 17 patients per year as incorparation measurements.

  12. [Analyses of spectral emissivity in radiation temperature measurement].

    Science.gov (United States)

    Fu, Tai-Ran; Cheng, Xiao-Fang; Zhong, Mao-Hua; Yang, Zang-Jian

    2008-01-01

    The complexity of the spectral emissivity of actual surfaces is the key point in the research and applications of radiation temperature measurement, resulting in the difficulty in the achievement of the temperature measurement. In the present paper, based on the discussions of the Taylor expansion, the non-dimension wavelength and the exponent, the authors describe the mathematical expression of the spectral emissivity of actual surfaces, and establish the general spectral emissivity function. Through the fitting of experimental data of the spectral emissivities of different metals at different temperatures, the applicability of the spectral emissivity function is verified which especially becomes the fundamental in the research of primary spectrum pyrometry. PMID:18422106

  13. Standard for nuclear-radiation moisture measuring devices

    International Nuclear Information System (INIS)

    The hydrophobic standard is destined for calibrating nuclear-radiation (thermal neutrons) moisture measuring instruments of the surface and depth measuring type. It consists of a pile of thin, alternating layers of moderating materials, as e.g. polyethylene, and metal, as e.g. magnesium. Both materials show no affinity towards moisture. The pile is dimensioned in a way that it offers an infinitely large mass of homogeneously distributed hydrogen to the instrument to be calibrated. The individual layers may exhibit equal or different thickness in order to be able to establish a calibration curve for the moisture content if different standards are used. (DG)

  14. The resistive bolometer for radiated power measurement on EAST.

    Science.gov (United States)

    Duan, Y M; Hu, L Q; Mao, S T; Chen, K Y; Lin, S Y

    2012-09-01

    The resistive bolometer system has been successfully employed on experimental advanced superconducting tokamak for the first time to measure the radiated power of plasma. The bolometer detectors are based on 4 μm thick Pt absorbers deposited on 1.5 μm thick SiN membranes. The system consists of 3 cameras with a total of 48 channels. The detector and the system setup are described in detail. The detector calibration and typical measurement results are presented as well. PMID:23025621

  15. The CENTAUR network contribution to the gene-based technology: Dissemination of information, international collaboration and training

    International Nuclear Information System (INIS)

    The CENTAUR Network (FAO Established Veterinary Biotechnology/Epidemiology Network for Central and Eastern Europe) is designed for cooperation and information of workers in state and regional veterinary directorates, veterinary practitioners, teachers from veterinary schools, advanced students, politicians specialized in agriculture, economy, science management, workers from diagnostic and research laboratories, breeders and other interested parties. It contributes to the use of the Internet, to the improvement of communication in English, to deepening of co-operation between workers with similar interests and to the better link with international organizations and internationally recognized centres of excellence. Formally, 23 countries officially belong to the CENTAUR network. However, in reality nearly one thousand CENTAUR network members are from the all continents. The membership is free and everybody can profit from all information offered. The CENTAUR is creating a protective belt for Central and Eastern European Countries especially those with the 'economies in transition' regarding the devastating Transboundary Animal Diseases such as bluetongue, foot and mouth disease and other vesicular diseases, rinderpest, peste des petits ruminants, contagious bovine pleuropneumonia, sheep and goat pox, classical swine fever, African swine fever, BSE/TSE, as well as other priority diseases and supports the prevention of a possible risk of biological terrorism. CENTAUR is based on the voluntary cooperation of countries concerned. The main task is to achieve compatibility of the disease control standards namely for better disease and contamination diagnosis and vaccine production, the modern computerized veterinary epidemiology and food safety and consumer protection with the OIE and EU international requirements. It is contributing to the accession of 8 Eastern European countries to the EU in 2004 and some other countries at a later stage. CENTAUR maintains in

  16. Science Plan for the Atmospheric Radiation Measurement Program (ARM)

    International Nuclear Information System (INIS)

    The purpose of this Atmospheric Radiation Measurement (ARM) Science Plan is to articulate the scientific issues driving the ARM Program, and to relate them to DOE's programmatic objectives for ARM, based on the experience and scientific progress gained over the past five years. ARM programmatic objectives are to: (1) Relate observed radiative fluxes and radiances in the atmosphere, spectrally resolved and as a function of position and time, to the temperature and composition of the atmosphere, specifically including water vapor and clouds, and to surface properties, and sample sufficient variety of situations so as to span a wide range of climatologically relevant possibilities; (2) develop and test parameterizations that can be used to accurately predict the radiative properties and to model the radiative interactions involving water vapor and clouds within the atmosphere, with the objective of incorporating these parameterizations into general circulation models. The primary observational methods remote sending and other observations at the surface, particularly remote sensing of clouds, water vapor and aerosols

  17. Measuring solar UV radiation with EBT radiochromic film

    Energy Technology Data Exchange (ETDEWEB)

    Butson, Ethan T [Illawarra Grammar School, (TIGS), Western Ave, West Wollongong, NSW (Australia); Cheung Tsang; Yu, Peter K N; Butson, Martin J, E-mail: diamonds.for.you@hotmail.co [Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong (Hong Kong)

    2010-10-21

    Ultraviolet radiation dosimetry has been performed with the use of a radiochromic film dosimeter called Gafchromic EBT for solar radiation exposure. The film changes from a clear colour to blue colour when exposed to ultraviolet radiation and results have shown that the colour change is reproducible within {+-}10% at 5 kJ m{sup -2} UV exposure under various conditions of solar radiation. Parameters tested included changes in season (summer versus winter exposure), time of day, as well as sky conditions such as cloudy skies versus clear skies. As the radiochromic films' permanent colour change occurs in the visible wavelengths the film can be analysed with a desktop scanner with the most sensitive channel for analysis being the red component of the signal. Results showed that an exposure of 5 kJ m{sup -2} (approximately 1 h exposure in full sun during summer) produced an approximate 0.28 change in the net OD when analysed in reflection mode on the desktop scanner which is significant darkening. The main advantages of this film type, and thus the new EBT2 film which has replaced EBT for measurement of UV exposure, is the visible colour change and thus easy analysis using a desktop scanner, its uniformity in response and its robust physical strength for use in outside exposure situations. (note)

  18. Measuring solar UV radiation with EBT radiochromic film

    International Nuclear Information System (INIS)

    Ultraviolet radiation dosimetry has been performed with the use of a radiochromic film dosimeter called Gafchromic EBT for solar radiation exposure. The film changes from a clear colour to blue colour when exposed to ultraviolet radiation and results have shown that the colour change is reproducible within ±10% at 5 kJ m-2 UV exposure under various conditions of solar radiation. Parameters tested included changes in season (summer versus winter exposure), time of day, as well as sky conditions such as cloudy skies versus clear skies. As the radiochromic films' permanent colour change occurs in the visible wavelengths the film can be analysed with a desktop scanner with the most sensitive channel for analysis being the red component of the signal. Results showed that an exposure of 5 kJ m-2 (approximately 1 h exposure in full sun during summer) produced an approximate 0.28 change in the net OD when analysed in reflection mode on the desktop scanner which is significant darkening. The main advantages of this film type, and thus the new EBT2 film which has replaced EBT for measurement of UV exposure, is the visible colour change and thus easy analysis using a desktop scanner, its uniformity in response and its robust physical strength for use in outside exposure situations. (note)

  19. Theory and measurement of emittance properties for radiation thermometry applications.

    Science.gov (United States)

    Dewitt, D. P.; Hernicz, R. S.

    1972-01-01

    Some basic concepts of radiation physics are briefly reviewed to provide an introduction to the radiative properties - including emittance, reflectance, absorptance, and transmittance - their definitions, interrelations, theory and methods of measurement. Analyzed data showing typical characteristics of temperature and wavelength dependence, surface effects and environmental influences on the radiation properties of selected classes of materials are presented. Emphasis is placed on those emittance properties of particular interest to conventional radiation thermometry applications, but sufficient generality on all properties is presented to be useful for new or unusual techniques where a more detailed understanding of the behavior of materials is desirable. Data sources are identified to assist the reader in locating property information. It is the intention of the paper to give the reader a background to become more fully aware of the pitfalls, limitations, but of course, advantages in the use of data from the literature. The paper is written in the form of an abbreviated review fully documenting the more important topics and concepts which can only be treated briefly.

  20. Absorbed dose measurements of mixed pile radiation in aqueous radiation chemistry

    International Nuclear Information System (INIS)

    To use a nuclear reactor as a radiation source in the radiation chemistry of water and aqueous solutions, reliable routine dosimetry techniques are of basic importance. For this purpose we have tried to develop a calorimetric device and a chemical system. The differential calorimeter described here permits simultaneous measurements of energy absorption in different materials. From these values the relative contributions from gammas and non-thermalized neutrons to the total absorbed dose can be calculated. The possibility of inserting a liquid sample into the calorimeter makes it very convenient for radiation chemical studies of aqueous solutions or, generally, liquid systems. For a period of about two years, reliable values for the absorbed doses in different materials have been obtained, which are in good agreement with other physical measurements in the RA research reactor at Vinca. The chemical system described is an aqueous solution of oxalic acid. Its advantages are: the possibility of measurements in the multi-megarad region and negligible induced radioactivity. The results of calorimetric and chemical measurements are presented

  1. Radiation exposure of staff and protection measures at medical applications of β-radiation

    International Nuclear Information System (INIS)

    Sealed and particularly unsealed beta radiation sources are increasingly used in medicine for radiation therapy. For example, inflammatory joint diseases are treated by radiosynoviorthesis (RSO), i. e. by injecting 90Y, 186Re or 169Er solutions. In vascular brachytherapy 90Sr/90Y, 32P or 188Re are used to cure so-called in-stent-restenosis patients. Recently, the radioimmunotherapy (RIT) of malign lymphoma with 90Y labeled antibodies has been introduced. All these practices are characterized by a high risk of partial body exposures to beta radiation, if radiation protection is not adequately taken into account. Investigations at several workplaces have been performed to estimate the exposure. The skin dose, Hp(0,07), to the hands was measured with thin-layer thermoluminescence detectors (TLD) that were fixed to the fingers of doctors and assistants. Typical values of maximum doses are presented which indicate that the local skin dose to the fingers of the staff can exceed the annual dose limit of 500 mSv. Consequently, adequate protection measures were recommended and investigated. An exposure reduction by one or two orders of magnitude could be observed. Moreover, general problems of routine monitoring of skin exposures with officially authorized extremity dosemeters are discussed. (orig.)

  2. Solar Radiation Measurements Onboard the Research Aircraft HALO

    Science.gov (United States)

    Lohse, I.; Bohn, B.; Werner, F.; Ehrlich, A.; Wendisch, M.

    2014-12-01

    Airborne measurements of the separated upward and downward components of solar spectral actinic flux densities for the determination of photolysis frequencies and of upward nadir spectral radiance were performed with the HALO Solar Radiation (HALO-SR) instrument package onboard the High Altitude and Long Range Research Aircraft (HALO). The instrumentation of HALO-SR is characterized and first measurement data from the Next-generation Aircraft Remote-Sensing for Validation Studies (NARVAL) campaigns in 2013 and 2014 are presented. The measured data are analyzed in the context of the retrieved microphysical and optical properties of clouds which were observed underneath the aircraft. Detailed angular sensitivities of the two optical actinic flux receivers were determined in the laboratory. The effects of deviations from the ideal response are investigated using radiative transfer calculations of atmospheric radiance distributions under various atmospheric conditions and different ground albedos. Corresponding correction factors are derived. Example photolysis frequencies are presented, which were sampled in the free troposphere and lower stratosphere over the Atlantic Ocean during the 2013/14 HALO NARVAL campaigns. Dependencies of photolysis frequencies on cloud cover, flight altitude and wavelength range of the photolysis process are investigated. Calculated actinic flux densities in the presence of clouds benefit from the measured spectral radiances. Retrieved cloud optical thicknesses and effective droplet radii are used as model input for the radiative transfer calculations. By comparison with the concurrent measurements of actinic flux densities the retrieval approach is validated. Acknowledgements: Funding by the Deutsche Forschungsgemeinschaft within the priority program HALO (BO 1580/4-1, WE 1900/21-1) is gratefully acknowledged.

  3. Radiation Load of Children by Chest Radiodiagnostic Measurements

    International Nuclear Information System (INIS)

    Radiodiagnostic examinations of children present particular importance from the radiation hygiene point of view. The estimation of the radiation load of pediatric patient is not easy, because of the lack of information about organ weighting factors for various ages of patients, as well as due to the differences in applied X-ray examination parameters. In the district of Slovak Republic, in which also the working Nuclear Power Plant Jaslovske Bohunice is included, efforts were done to estimate the radiation load of children to 15 years by chest radiodiagnostic examinations. The data of entrance surface doses were collected using measurements with TLD for 100 patients divided in 5 age categories at six radiodiagnostic departments. The calculations of the total absorbed dose were performed using the measured ESD values (entrance surface dose in mGy) integrated over the X-ray beam area, the conversion factors between the imparted energy and the dose-area product and the known irradiation parameters (kV, HVL, mass, etc.). The analysis of the obtained absorbed doses (Ea) as a function of age for chest PA radiodiagnostic examinations has shown, that the investigated Slovak radiodiagnostic centres use rather lower voltage techniques and the entrance surface doses are much higher than the proposed value of European Communities. (author)

  4. Radiation measurements around X-ray cabinet systems.

    Science.gov (United States)

    Suric Mihic, M; Vucic, Z; Prlic, I; Lulic, I; Mestrovic, T

    2012-07-01

    Security personnel who operate X-ray units for the control of hand luggage and personal items at airports are generally not under dosimetric surveillance. A significant increase in the number of inspected items per passenger, due to rigorous air traffic security measures, raises a question of extended exposure of these workers to scattered X-ray radiation. A new approach to investigating directions of breaches of scattered X-ray radiation in the area near to an X-ray cabinet system, which is based on using active electronic dosemeters is presented. Influence of the increase in the number of inspected items in time on the dose rate is described. Time-dependent dose rates have showed a very good correlation with passengers undergoing security control prior to boarding an airplane. Measurements confirmed that an increase in the dose rate, coinciding with rush hours, was caused by scattered radiation passing through incompletely closed lead curtains. It is found that the doses at the entrance to the inspection tunnel are 50% higher than those at the exit, which is a consequence of inherent operational characteristics of X-ray cabinet systems. PMID:22302108

  5. Design and implementation of a virtual laboratory of radiation measurement

    International Nuclear Information System (INIS)

    The work involves the implementation of a virtual laboratory, this project is conducted in the Faculty of Engineering of National Autonomous University of Mexico with the name of LANUVI. It is intended that the laboratory can be used by students who have interest in the nuclear radiation knowledge as well as in its detection and attenuation, in addition serve as and introduction to nuclear systems. In the first part of project will conduct a source that can simulate the particle radiation of Alfa, beta, neutrons and gamma rays. The project will take sources used in class laboratories and elements that are dangerous but are used in different practical applications. After taking the source analyzing the particles behaviour in different media like air, animal tissue, aluminium, lead, etc. The analysis is done in different ways in order to know with which material can stop or mitigate the different types of radiation. Finally shall be measure radioactivity with different types of detectors. At this point, has the behaviour of ionization chamber but in the future is expected to make the simulation of some other radiation detectors. The mathematical models we represent the behaviour of these cases were implemented in free software. The program will be used to implement the virtual laboratory with radiation sources, detectors and different types of shields will be Blender which is a free software that is used by many users for the embodiment of games but try to use as a tool to help visualize the different equipment that is widely used in a radioactive materials laboratory. (Author)

  6. Atmospheric thermal radiation from historical measurements to investigations of the Earth's greenhouse effect

    OpenAIRE

    Rolf Philipona

    2013-01-01

    Here, we recall first quantitative measurements of terrestrial and atmospheric thermal infrared radiation that were made about hundred years ago, and relate them to present day radiation budget measurements and greenhouse effect investigations through the atmosphere. At the beginning of the 20th century measurements of the effective terrestrial radiation and the counter-radiation of the atmosphere were of great interest primarily to prove theoretical aspects of the Earth radiation balance...

  7. Measurement of radiation dose at the north interaction point of BEPCⅡ

    Institute of Scientific and Technical Information of China (English)

    MO Xiao-Hu; ZHANG Jian-Yong; ZHANG Tian-Bao; ZHANG Qing-Jiang; Achasov Mikhail; FU Cheng-Dong; Muchnoi Nikolay; QIN Qing; QU Hua-Min; WANG Yi-Fang; WU Jing-Min; XU Jin-Qiang; YU Bo-Xiang

    2009-01-01

    The technique details for measuring radiation dose are expounded.The results of gamma and neutron radiation levels are presented and the corresponding radiation shielding is discussed based on the simplified estimation.In addition, the photon radiation level move as background for future experiments is measured by a NaI(T1) detector.

  8. Measurement of radiative Bhabha and quasi-real Compton scattering

    CERN Document Server

    Acciarri, M; Aguilar-Benítez, M; Ahlen, S P; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Ambrosi, G; Anderhub, H; Andreev, V P; Angelescu, T; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Baksay, L; Banerjee, S; Banerjee, Sw; Banicz, K; Barczyk, A; Barillère, R; Barone, L; Bartalini, P; Baschirotto, A; Basile, M; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Bhattacharya, S; Biasini, M; Biland, A; Bilei, G M; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böck, R K; Böhm, A; Boldizsar, L; Borgia, B; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brigljevic, V; Brock, I C; Buffini, A; Buijs, A; Burger, J D; Burger, W J; Busenitz, J K; Cai, X D; Campanelli, M; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Castellini, G; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada-Canales, M; Cesaroni, F; Chamizo-Llatas, M; Chang, Y H; Chaturvedi, U K; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chéreau, X J; Chiefari, G; Chien, C Y; Cifarelli, Luisa; Cindolo, F; Civinini, C; Clare, I; Clare, R; Coignet, G; Colijn, A P; Colino, N; Costantini, S; Cotorobai, F; de la Cruz, B; Csilling, Akos; Dai, T S; D'Alessandro, R; De Asmundis, R; Degré, A; Deiters, K; Della Volpe, D; Denes, P; De Notaristefani, F; Diemoz, M; Van Dierendonck, D N; Di Lodovico, F; Dionisi, C; Dittmar, Michael; Dominguez, A; Doria, A; Dova, M T; Duchesneau, D; Duinker, P; Durán, I; Easo, S; El-Mamouni, H; Engler, A; Eppling, F J; Erné, F C; Ernenwein, J P; Extermann, Pierre; Fabre, M; Faccini, R; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Ferguson, T; Ferroni, F; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisk, I; Forconi, G; Fredj, L; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gau, S S; Gentile, S; Gheordanescu, N; Giagu, S; Goldfarb, S; Goldstein, J; Gong, Z F; Gougas, Andreas; Gratta, Giorgio; Grünewald, M W; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hartmann, B; Hasan, A; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hidas, P; Hirschfelder, J; Van Hoek, W C; Hofer, H; Hoorani, H; Hou, S R; Hu, G; Iashvili, I; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kasser, A; Khan, R A; Kamrad, D; Kapustinsky, J S; Karyotakis, Yu; Kaur, M; Kienzle-Focacci, M N; Kim, D; Kim, D H; Kim, J K; Kim, S C; Kinnison, W W; Kirkby, A; Kirkby, D; Kirkby, Jasper; Kiss, D; Kittel, E W; Klimentov, A; König, A C; Kopp, A; Korolko, I; Koutsenko, V F; Krämer, R W; Krenz, W; Kunin, A; Lacentre, P E; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lapoint, C; Lassila-Perini, K M; Laurikainen, P; Lavorato, A; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Lee, H J; Le Goff, J M; Leiste, R; Leonardi, E; Levchenko, P M; Li Chuan; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lu, W; Lü, Y S; Lübelsmeyer, K; Luci, C; Luckey, D; Luminari, L; Lustermann, W; Ma Wen Gan; Maity, M; Majumder, G; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Marchesini, P A; Marian, G; Marin, A; Martin, J P; Marzano, F; Massaro, G G G; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Von der Mey, M; Migani, D; Mihul, A; Van Mil, A J W; Milcent, H; Mirabelli, G; Mnich, J; Molnár, P; Monteleoni, B; Moore, R; Moulik, T; Mount, R; Muheim, F; Muijs, A J M; Nahn, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nippe, A; Nisati, A; Nowak, H; Oh, Yu D; Organtini, G; Ostonen, R; Palit, S; Palomares, C; Pandoulas, D; Paoletti, S; Paolucci, P; Park, H K; Park, I H; Pascale, G; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Peach, D; Pei, Y J; Pensotti, S; Perret-Gallix, D; Petersen, B; Petrak, S; Pevsner, A; Piccolo, D; Pieri, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Postema, H; Pothier, J; Produit, N; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Raja, N; Rancoita, P G; Rattaggi, M; Raven, G; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Van Rhee, T; Riemann, S; Riles, K; Robohm, A; Rodin, J; Roe, B P; Romero, L; Rosier-Lees, S; Roth, S; Rubio, Juan Antonio; Ruschmeier, D; Rykaczewski, H; Sakar, S; Salicio, J; Sánchez, E; Sanders, M P; Sarakinos, M E; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Scholz, N; Schopper, Herwig Franz; Schotanus, D J; Schwenke, J; Schwering, G; Sciacca, C; Sciarrino, D; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shukla, J; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Smith, B; Spillantini, P; Steuer, M; Stickland, D P; Stone, A; Stone, H; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Susinno, G F; Suter, H; Swain, J D; Tang, X W; Tauscher, Ludwig; Taylor, L; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Uchida, Y; Ulbricht, J; Valente, E; Vesztergombi, G; Vetlitskii, I; Viertel, Gert M; Vivargent, M; Vlachos, S; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Vorvolakos, A; Wadhwa, M; Wallraff, W; Wang, J C; Wang, X L; Wang, Z M; Weber, A; Wu, S X; Wynhoff, S; Xu, J; Xu, Z Z; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Ye, J B; Yeh, S C; You, J M; Zalite, A; Zalite, Yu; Zemp, P; Zeng, Y; Zhang, Z P; Zhou, B; Zhu, G Y; Zhu, R Y; Zichichi, Antonino; Ziegler, F; Zilizi, G

    1998-01-01

    We report on a study of radiative Bhabha and quasi-real Compton scattering at centre-of-mass energies between 50~{\\GeV} and 170~{\\GeV} and 20~{\\GeV} and 140~{\\GeV}, respectively, using the L3 detector at LEP. The analysis is based on data corresponding to an integrated luminosity of $232.2 \\,\\pb$. A total of 2856 radiative Bhabha and 4641 Compton scattering events are collected. Total and differential cross sections for both reactions are presented and found to be in good agreement with QED expectations. Our measurement of Compton scattering at the highest energies obtained so far is used to derive exclusion limits on the coupling $\\lambda$ for the on-shell production of an excited electron $\\e^{\\star}$ decaying into a $\\gamma\\e$ pair in the mass range $20 \\gev < m_{\\e^{\\star}} < 170 \\gev$.

  9. Action of liposomal superoxide dismutase on measurable radiation - induced fibroses

    International Nuclear Information System (INIS)

    Radiation-induced fibroses are a classical complication of radiotherapy. The effect of liposomal superoxide dismutase (Lipsod) on 45 radiation-induced fibroses of measurable volume and hardness in 34 patients was studied Over 3 weeks, 6 injections of Lipsod were given intramuscularly: 5 mg for 28 patients and 2 mg for 6 patients. On the average, the volume decreased by 32%. A marked or moderate softening was observed in 80% of the fibroses; it was accompanied by functional improvement in 75% of the patients (in cases of preexisting difficulties). The effectiveness was independent of the time lag between the Lipsod treatment and irradiation. The decreases noted in the volume and hardness of the fibroses remained stable during a follow up of 5-24 months. This systematic study shows the interest of Lipsod treatment of quasi-experimental fibroses where no other effective therapy exists

  10. Electromagnetic Radiation Measurements and Safety Issues of some Cellular

    Directory of Open Access Journals (Sweden)

    A. Mousa

    2011-01-01

    Full Text Available As the mobile telecommunication systems are tremendously growing allover the world then the numbers of handheld andbase stations are also rapidly growing and it became very popular to see these base stations distributed everywhere in theneighborhood and on roof tops which has caused a considerable amount of panic to the public in Palestine concerning witherthe radiated electromagnetic field from these base stations may cause any health effect or hazard. This paper focuses on theradiated electromagnetic energy from some typical mobile base stations around the city of Nablus. The exposure levels dueto these stations were measured and compared to some international standard guidelines like ICNIRP and FCC to see if itmeets these standards, this is in order to answer some of the public fear and concern. The results are presented and somecomments are made on the other sources of electromagnetic radiation in the 200 kHz to 3 GHz range.

  11. Calibration facilities for borehole and surface environmental radiation measurements

    International Nuclear Information System (INIS)

    Measuring radiation from contaminated soil and buildings is important in the cleanup of land areas and facilities. It provides the means for quantifying the amount of contamination and assessing the success of efforts to restore areas to acceptable conditions for public use. Instruments that measure in situ radiation from natural or radiochemically-contaminated earth formations must be calibrated in appropriate facilities to provide quantitative assessments of concentrations of radionuclides. For instruments that are inserted into boreholes, these calibration facilities are typically special models having holes for probe insertion and having sufficient size to appear radiometrically ''infinite'' in extent. The US Department of Energy (DOE) has such models at Hanford, Washington, and Grand Junction, Colorado. They are concrete cylinders having a central borehole and containing known, enhanced amounts of K, U, and Th for spectral gamma-ray measurements. Additional models contain U for calibrating neutron probes for fissile materials and total-count gamma-ray probes. Models for calibrating neutron probes for moisture measurements in unsaturated formations exist for steel-cased boreholes at Hanford and for uncased boreholes at the DOE's Nevada Test Site. Large surface pads are available at Grand Junction for portable, vehicle-mounted, or airplane-mounted spectral gamma-ray detectors

  12. Atmospheric radiation measurement: A program for improving radiative forcing and feedback in general circulation models

    International Nuclear Information System (INIS)

    The Atmospheric Radiation Measurement (ARM) Program is a key element of the Department of Energy's (DOE's) global change research strategy. ARM represents a long-term commitment to conduct comprehensive studies of the spectral atmospheric radiative energy balance profile for a wide range of cloud conditions and surface types, and to develop the knowledge necessary to improve parameterizations of radiative processes under various cloud regimes for use in general circulation models (GCMs) and related models. The importance of the ARM program is a apparent from the results of model assessments of the impact on global climate change. Recent studies suggest that radiatively active trace gas emissions caused by human activity can lead to a global warming of 1.5 to 4.5 degrees Celsius and to important changes in water availability during the next century (Cess, et al. 1989). These broad-scale changes can be even more significant at regional levels, where large shifts in temperature and precipitation patterns are shown to occur. However, these analyses also indicate that considerable uncertainty exists in these estimates, with the manner in which cloud radiative processes are parameterized among the most significant uncertainty. Thus, although the findings have significant policy implications in assessment of global and regional climate change, their uncertainties greatly influence the policy debate. ARM's highly focused observational and analytical research is intended to accelerate improvements and reduce key uncertainties associated with the way in which GCMs treat cloud cover and cloud characteristics and the resulting radiative forcing. This paper summarizes the scientific context for ARM, ARM's experimental approach, and recent activities within the ARM program

  13. Measurement of radiation dose in cerebral CT perfusion study

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate radiation dose in cerebral perfusion studies with a multi-detector row CT (MDCT) scanner on various voltage and current settings by using a human head phantom. Following the CT perfusion study protocol, continuous cine scans (1 sec/rotation x 60 sec) consisting of four 5-mm-thick contiguous slices were performed three times at variable tube voltages of 80 kV, 100 kV, 120 kV, and 140 kV with the same tube current setting of 200 mA and on variable current settings of 50 mA, 100 mA, 150 mA, and 200 mA with the same tube voltage of 80 kV. Radiation doses were measured using a total of 41 thermoluminescent dosimeters (TLDs) placed in the human head phantom. Thirty-six TLDs were inside and three were on the surface of the slice of the X-ray beam center, and two were placed on the surface 3 cm caudal assuming the lens position. Average radiation doses of surface, inside, and lens increased in proportion to the increases of tube voltage and tube current. The lowest inside dose was 87.6±15.3 mGy, and the lowest surface dose was 162.5±6.7 mGy at settings of 80 kV and 50 mA. The highest inside dose was 1,591.5±179.7 mGy, and the highest surface dose was 2,264.6±123.7 mGy at 140 kV-200 mA. At 80 kV-50 mA, the average radiation dose of lens was the lowest at 5.5±0.0 mGy. At 140 kV-200 mA the radiation dose of lens was the highest at 127.2±0.6 mGy. In cerebral CT perfusion study, radiation dose can vary considerably. Awareness of the patient's radiation dose is recommended. (author)

  14. Radiation education for high school students by measurement sharing method using radiation sources fabricated from potassium chloride chemicals

    International Nuclear Information System (INIS)

    In the National Institute for Fusion Science, various exercises are practiced for high school students. One of the exercises is an environmental radiation measurement. In the recent exercise we began to use potassium chloride radiation sources that contained the naturally occurring radioisotope potassium-40. In this study, a measurement sharing method was first applied to the measurements. Through the exercise, students understood the existence of natural radiation and radioisotopes around us, and learned the three principles of radiation protection. According to the questionnaire survey conducted after the exercise, it was found that the environmental radiation measurement by the measurement sharing method using potassium chloride radiation sources was favorably received by many high school students. (author)

  15. Technical measures and engineering management measures for radiation protection in underground uraniferous coal mine

    International Nuclear Information System (INIS)

    The reserves of uraniferous coal resource account for a certain proportion of all uranium resources in China. China began to mine the uraniferous coal deposits in late 1960s. In the process of mining, much research was conducted on the control and reduction of the radiation hazards in underground uraniferous coal mine. However, such mining practice was stopped for many reasons in late 1980s. During recent years, electricity shortages have taken place from time to time. In order to alleviate the shortages, the Chinese government has decided to further develop nuclear electricity. Under such circumstances, underground mining of uraniferous coal deposits will be restarted. In order to make sure that the radiation protection will be stressed and the radiation hazards will be controlled effectively in the underground uraniferous mine, this paper gives the basic knowledge of radiation protection, describes the radiation hazards to the miners and our national dosage standards implemented in the underground mine, and, on the basis of summing-up of the past experience in mine radiation protection, presents the technical and management measures for controlling and reducing radiation hazards. (authors)

  16. ISS Radiation Measurements using the Dosimetric Mapping Experiment

    Science.gov (United States)

    Reitz, G.; Beaujean, R.; Dachev, T.; Deme, S.; Luszik-Bhadra, M.; Heinrich, W.; Olko, P.; Scherkenbach, M.

    The experiment SDosimetric MappingT was flown as part of the Human Research Facility (HRF), NASASs first science payload on the ISS. The experiment consists of five nuclear track detector packages (NTDPs) (thermoluminescence dosimeters (TLD) and plastic nuclear track detectors), two DOSimetry TELescopes (DOSTEL) using two passive implanted planar silicon detectors per instrument, four Mobile Dosimetry Units (MDUs) using one passive implanted planar silicon detector per unit with an Control and Interface Unit (CIU) and an onboard TLD system consisting of a small weight TLD Reader and twelve TLD-bulbs, which have been reused after each mea- surement. Detectors are spread over the whole US-Lab. Data were transferred during the mission via the HRF Laptop to the ground. Dose rates of the ionizing part of the radiation field measured with TLD-bulbs at different locations vary between 123μGy/d and 226 μG/d. The dose rate received by the active devices fits excellent to the TLD measurements and is significantly lower compared to measurements on the STS missions to MIR. The measurements on the ISS yielded a mean dose equivalent of 504 μSv/day applying a radiation quality factor of 2.6 based on the recommendations of ICRP Report No. 60 and determined from the measured LET spectra of the DOSTEL instrument. The mean dose rate was with 194 μGy/d significantly lower compared to DOSTEL measurements on the STS missions. DOSTEL measurements were also obtained during the Solar Particle Event (SPE) on April 15, 2001. The presentation includes beside first results, some data on calibration work and an intercomparison between the different detector systems.

  17. Influence of Spherical Radiation Pattern Measurement Uncertainty on Handset Performance Measures

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ødum; Pedersen, Gert Frølund

    2005-01-01

    An important characteristic of a mobile handset is its ability to receive and transmit power. One way to characterize the performance of a handset in this respect is to use measurements of the spherical radiation pattern from which the total radiated power (TRP), total isotropic sensitivity (TIS...... in the performance measures are investigated for both the GSM-900 and the GSM-1800 band. Despite the deliberately large deviations from the reference position, the changes in TRP and TIS are generally within ±0.5 dB with a maximum of about 1.4 dB. For the MEG values the results depend on the orientation...

  18. Soot and Radiation Measurements in Microgravity Jet Diffusion Flames

    Science.gov (United States)

    Ku, Jerry C.

    1996-01-01

    The subject of soot formation and radiation heat transfer in microgravity jet diffusion flames is important not only for the understanding of fundamental transport processes involved but also for providing findings relevant to spacecraft fire safety and soot emissions and radiant heat loads of combustors used in air-breathing propulsion systems. Our objectives are to measure and model soot volume fraction, temperature, and radiative heat fluxes in microgravity jet diffusion flames. For this four-year project, we have successfully completed three tasks, which have resulted in new research methodologies and original results. First is the implementation of a thermophoretic soot sampling technique for measuring particle size and aggregate morphology in drop-tower and other reduced gravity experiments. In those laminar flames studied, we found that microgravity soot aggregates typically consist of more primary particles and primary particles are larger in size than those under normal gravity. Comparisons based on data obtained from limited samples show that the soot aggregate's fractal dimension varies within +/- 20% of its typical value of 1.75, with no clear trends between normal and reduced gravity conditions. Second is the development and implementation of a new imaging absorption technique. By properly expanding and spatially-filtering the laser beam to image the flame absorption on a CCD camera and applying numerical smoothing procedures, this technique is capable of measuring instantaneous full-field soot volume fractions. Results from this technique have shown the significant differences in local soot volume fraction, smoking point, and flame shape between normal and reduced gravity flames. We observed that some laminar flames become open-tipped and smoking under microgravity. The third task we completed is the development of a computer program which integrates and couples flame structure, soot formation, and flame radiation analyses together. We found good

  19. Radiation measurements in Austria in 1999 - date and evaluation

    International Nuclear Information System (INIS)

    natural radiation exposure do occur. There are regions with particular geological conditions where exposure levels by far exceed the average dose due to high radon values. Artificial radiation exposure is predominantly caused by the use of radioactive substances and of ionizing radiation in medical applications, in particular by x-ray diagnostics, leading on the average to approximately 1.3 mSv per person annually in the reporting period. By comparison, the dose to the Austrian population due to the effects of the reactor accident at Chernobyl amounting in 1999 to less than 0.02 mSv is small. The exposure as a result of the operation of the nuclear installations at the Austrian Research Center Seibersdorf and at the Atomic Institute of the Austrian Universities in 1999 was negligible. Investigative measurements by the authorities of gaseous and liquid emissions and the internal surveillance by the operators show that maximum permissible levels never were exceeded. Also environmental monitoring in the surroundings could not detect any inadmissibly high gamma dose rates or immissions. The artificial radionuclide content of air, precipitation and surface water in the reporting period was mainly caused by the Chernobyl accident and similarly low as in the previous years. In these media the values for caesium-137 - which nowadays is the only significant radionuclide left from the Chernobyl fallout - are only slightly higher than before the accident. However, in soils from certain regions much higher caesium-137 concentrations can be found than before the accident. Since in most agriculturally used sods radiocaesium is fixed strongly to clay minerals and thus is only marginally available for plant uptake, foodstuffs and agricultural products generally show only minor caesium-137 concentrations. In comparison, significantly higher values still can be found in some forest produce such as wild growing fungi and game. In semi-natural forest ecosystems the fixation of caesium is

  20. Background Radiation Measurements at High Power Research Reactors

    CERN Document Server

    Ashenfelter, J; Baldenegro, C X; Band, H R; Barclay, G; Bass, C D; Berish, D; Bowden, N S; Bryan, C D; Cherwinka, J J; Chu, R; Classen, T; Davee, D; Dean, D; Deichert, G; Dolinski, M J; Dolph, J; Dwyer, D A; Fan, S; Gaison, J K; Galindo-Uribarri, A; Gilje, K; Glenn, A; Green, M; Han, K; Hans, S; Heeger, K M; Heffron, B; Jaffe, D E; Kettell, S; Langford, T J; Littlejohn, B R; Martinez, D; McKeown, R D; Morrell, S; Mueller, P E; Mumm, H P; Napolitano, J; Norcini, D; Pushin, D; Romero, E; Rosero, R; Saldana, L; Seilhan, B S; Sharma, R; Stemen, N T; Surukuchi, P T; Thompson, S J; Varner, R L; Wang, W; Watson, S M; White, B; White, C; Wilhelmi, J; Williams, C; Wise, T; Yao, H; Yeh, M; Yen, Y -R; Zhang, C; Zhang, X

    2016-01-01

    Research reactors host a wide range of activities that make use of the intense neutron fluxes generated at these facilities. Recent interest in performing measurements with relatively low event rates, e.g. reactor antineutrino detection, at these facilities necessitates a detailed understanding of background radiation fields. Both reactor-correlated and naturally occurring background sources are potentially important, even at levels well below those of importance for typical activities. Here we describe a comprehensive series of background assessments at three high-power research reactors, including $\\gamma$-ray, neutron, and muon measurements. For each facility we describe the characteristics and identify the sources of the background fields encountered. The general understanding gained of background production mechanisms and their relationship to facility features will prove valuable for the planning of any sensitive measurement conducted therein.

  1. Nuclear fragmentation measurements for hadrontherapy and space radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    De Napoli, M. [INFN - Sezione di Catania (Italy); Agodi, C.; Blancato, A. A.; Cavallaro, M.; Cirrone, G. A. P.; Cuttone, G.; Sardina, D.; Scuderi, V. [INFN - Laboratori Nazionali del Sud (Italy); Battistoni, G. [INFN - Sezione di Milano (Italy); Bondi, M.; Cappuzzello, F.; Carbone, D.; Nicolosi, D.; Raciti, G.; Tropea, S. [INFN - Laboratori Nazionali del Sud, Italy and Dipartimento di Fisica e Astronomia, Universita degli Studi di Catania (Italy); Giacoppo, F. [Department of Physics, University of Oslo (Norway); Morone, M. C. [Dipartimento di Biopatologia e Diagnostica per Immagini, Universita di Roma Tor Vergata (Italy); Pandola, L. [INFN-Laboratori Nazionali del Gran Sasso (Italy); Rapisarda, E. [Nuclear and Radiation Physics Section, Katholieke Universiteit Leuven Celestijnenlaan Heverlee (Belgium); Romano, F. [INFN - Laboratori Nazionali del Sud (Italy) and Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi Roma (Italy); and others

    2013-04-19

    Nuclear fragmentation measurements are necessary in hadrontherapy and space radiation protection, to predict the effects of the ion nuclear interactions within the human body. Nowadays, a very limited set of carbon fragmentation cross sections has been measured and in particular, to our knowledge, no double differential fragmentation cross sections at intermediate energies are available in literature. We have measured the double differential cross sections and the angular distributions of the secondary fragments produced in the {sup 12}C fragmentation at 62 AMeV on a thin carbon target. The experimental data have been also used to benchmark the prediction capability of the Geant4 Monte Carlo code at intermediate energies, where it was never tested before.

  2. The emittance of space radiator materials measured at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Mirtich, M.J. [Lewis Research Center, Cleveland, OH (United States); DiFilippo, F. [Case Western Reserve Univ., Cleveland, OH (United States); Barry, J.; Kussmaul, M. [Cleveland State Univ., OH (United States)

    1994-09-01

    The spectral emittances of textured space radiator materials between 1.7 and 14.7 {mu}m have been evaluated at room temperature and elevated temperature (630{degrees}C) in air. Heating in air caused a permanent increase in spectral emittance for all materials tested: HCl/ion beam textured 304 stainless steel, untextured Ti (6 percent Al, 4 percent V), and sandblasted Ti (6 percent Al, 4 percent V). Changes in the surface chemistry and/or surface morphology of these materials were also observed. Elevated temperature spectral emittance was measured in an argon atmosphere and compared to the measurements in air. Similarity between the room temperature and elevated temperature spectral emittance measurements was also investigated, and limited agreement was found.

  3. Background radiation measurements at high power research reactors

    Science.gov (United States)

    Ashenfelter, J.; Balantekin, B.; Baldenegro, C. X.; Band, H. R.; Barclay, G.; Bass, C. D.; Berish, D.; Bowden, N. S.; Bryan, C. D.; Cherwinka, J. J.; Chu, R.; Classen, T.; Davee, D.; Dean, D.; Deichert, G.; Dolinski, M. J.; Dolph, J.; Dwyer, D. A.; Fan, S.; Gaison, J. K.; Galindo-Uribarri, A.; Gilje, K.; Glenn, A.; Green, M.; Han, K.; Hans, S.; Heeger, K. M.; Heffron, B.; Jaffe, D. E.; Kettell, S.; Langford, T. J.; Littlejohn, B. R.; Martinez, D.; McKeown, R. D.; Morrell, S.; Mueller, P. E.; Mumm, H. P.; Napolitano, J.; Norcini, D.; Pushin, D.; Romero, E.; Rosero, R.; Saldana, L.; Seilhan, B. S.; Sharma, R.; Stemen, N. T.; Surukuchi, P. T.; Thompson, S. J.; Varner, R. L.; Wang, W.; Watson, S. M.; White, B.; White, C.; Wilhelmi, J.; Williams, C.; Wise, T.; Yao, H.; Yeh, M.; Yen, Y.-R.; Zhang, C.; Zhang, X.

    2016-01-01

    Research reactors host a wide range of activities that make use of the intense neutron fluxes generated at these facilities. Recent interest in performing measurements with relatively low event rates, e.g. reactor antineutrino detection, at these facilities necessitates a detailed understanding of background radiation fields. Both reactor-correlated and naturally occurring background sources are potentially important, even at levels well below those of importance for typical activities. Here we describe a comprehensive series of background assessments at three high-power research reactors, including γ-ray, neutron, and muon measurements. For each facility we describe the characteristics and identify the sources of the background fields encountered. The general understanding gained of background production mechanisms and their relationship to facility features will prove valuable for the planning of any sensitive measurement conducted therein.

  4. Intercomparison of Shortwave Radiative Transfer Codes and Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Halthore, Rangasayi N.; Crisp, David; Schwartz, Stephen E.; Anderson, Gail; Berk, A.; Bonnel, B.; Boucher, Olivier; Chang, Fu-Lung; Chou, Ming-Dah; Clothiaux, Eugene E.; Dubuisson, P.; Fomin, Boris; Fouquart, Y.; Freidenreich, S.; Gautier, Catherine; Kato, Seiji; Laszlo, Istvan; Li, Zhanqing; Mather, Jim H.; Plana-Fattori, Artemio; Ramaswamy, V.; Ricchiazzi, P.; Shiren, Y.; Trishchenko, A.; Wiscombe, Warren J.

    2005-06-03

    Computation of components of shortwave (SW) or solar irradiance in the surface-atmospheric system forms the basis of intercomparison between 16 radiative transfer models of varying spectral resolution ranging from line-by-line models to broadband and general circulation models. In order of increasing complexity the components are: direct solar irradiance at the surface, diffuse irradiance at the surface, diffuse upward flux at the surface, and diffuse upward flux at the top of the atmosphere. These components allow computation of the atmospheric absorptance. Four cases are considered from pure molecular atmospheres to atmospheres with aerosols and atmosphere with a simple uniform cloud. The molecular and aerosol cases allow comparison of aerosol forcing calculation among models. A cloud-free case with measured atmospheric and aerosol properties and measured shortwave radiation components provides an absolute basis for evaluating the models. For the aerosol-free and cloud-free dry atmospheres, models agree to within 1% (root mean square deviation as a percentage of mean) in broadband direct solar irradiance at surface; the agreement is relatively poor at 5% for a humid atmosphere. A comparison of atmospheric absorptance, computed from components of SW radiation, shows that agreement among models is understandably much worse at 3% and 10% for dry and humid atmospheres, respectively. Inclusion of aerosols generally makes the agreement among models worse than when no aerosols are present, with some exceptions. Modeled diffuse surface irradiance is higher than measurements for all models for the same model inputs. Inclusion of an optically thick low-cloud in a tropical atmosphere, a stringent test for multiple scattering calculations, produces, in general, better agreement among models for a low solar zenith angle (SZA = 30?) than for a high SZA (75?). All models show about a 30% increase in broadband absorptance for 30? SZA relative to the clear-sky case and almost no

  5. Sensor intercomparison of distributed surface radiation measurement system

    Science.gov (United States)

    Dou, Baocheng; Wen, Jianguang; Li, Xiuhong; Liu, Qiang; Xiao, Qing; Bai, Junhua; Peng, Jingjing; Lin, Xingwen; Zhang, Zhigang; Wu, Xiaodan; Cai, Erli; Zhang, Jialin; Chang, Chongyan

    2015-12-01

    The Wireless Sensor Networks of Coarse-resolution Pixel Parameters (CPP-WSN) was established to monitor the heterogeneity of coarse spatial resolution pixel, with consideration of different categories of land surface parameters in Huailai, Hebei province, China (40.349°N, 115.785°E). The observation network of radiation parameters (RadNet) in CPP-WSN was developed for multi-band radiation measurement and consisted of 6 nodes covering 2km*2km area to capture its heterogeneity. Each node employed four sensors to observe the five radiation parameters. The number and location of nodes in RadNet were determined through the representativeness-based sampling method. Thus, the RadNet is a distributed observation system with nodes work synchronously and measurements used together. The intercomparison experiment for RadNet is necessary and was conducted in Huailai Remote Sensing Station from 5th Aug to 10th Aug in 2012. Time series observations from various sensors were collected and analyzed. The maximum relative differences among sensors of UVR, SWR, LWR, PAR, and LST are 4.83%, 5.3%, 3.71%, 11%, and 0.54%, respectively. Sensor/parameter differences indeed exist and are considerable large for PAR, SWR, UVR, and LWR, which cannot be ignored. The linear normalization and quadratic polynomial normalization perform similar for CUV5/UVR, PQS1/PAR, CNR4/SWR, and SI-111/LST. As for CNR4/LWR, quadratic polynomial normalization show higher accuracy than linear normalization, especially in node2, node4, and node5. Thus, the LWR measured by CNR4 is proved to be nonlinear, and should be normalized with quadratic polynomial coefficients for higher precision.

  6. Measurements of environmental radiations and radioactivities in Toki, 4

    International Nuclear Information System (INIS)

    This is a series of reports concerning the achievements of an IPP-Toki collaborational work on the environmental survey of radiations and radioactivities in Toki Area, where the new IPP experimental site is to be constructed. A School Teachers' Group of Science has been organized in Toki and been active in good cooperation with the Environmental Measurement Working Group (formerly, Site and Facilities Team) of IPP to perform various kinds of measurement over the area. In this fourth issue of the series are contained several articles mainly discussing the results obtained in 1984 ∼ 85 period, including the following topics: 1) Method of In-Situ γ-Spectrometry with a Portable Ge-Detector, 2) Observed Radioactivities in Various Parts of Toki, 3) Method of Environmental Tritium Measurement, 4) Observed Tritium Concentrations in River Waters in Toki, 5) Summary of Radiation Dose Rates Observed in Toki 1982 ∼ 84, 6) 1985 TLD Observations in Toki, 7) Reports of Visits to Several Facilities in Japan. (author)

  7. Measurement of radiation dose in paediatric micturating cystourethrography

    International Nuclear Information System (INIS)

    Paediatrics and children have been recognized that they have a higher risk of developing cancer from the radiation than adults. Therefor, increased attention has been directed towards the dose to the patients. Micturating Cystourethrography (MCU) is a commonly use ed fluoroscopic procedure in children and commonly used to detect the vesicoureteric reflux (VUR) and show urethral and bladder and abnormalities. This study aims to measure the pediatric patients undergoing MCU. The study was carried out in two hospitals in Khartoum. The entrance surface dose (ESD) was determined determined by indirect method for 45 children. Furthermore, the mean ESD, sd and range resulting from MCU procedures has been estimated to be 0.7±.5 (0.2-2.5) mGy for the total patient population. The radiation dose to the patients is well within established safety limits, in the light of the current practice. The radiation dose results of this study are appropriate for adoption as the local initial dose reference level (DRL) value for this technique. The data presented in this study showed our doses to be approximately 50% lower than the lower mean values presented in the literature.(Author)

  8. Radiation exposure of patients due to medical measures

    International Nuclear Information System (INIS)

    The main objective of this research project supported by the Federal Ministry of the Interior was to collect the data required as a basis for an up-to-date assessment of the radiation exposure of the population as a result of medical measures. Apart from the fact that this had to be done in order to fulfill a commitment required by the EURATOM principles, the report in hand also presents a useful survey of the improvements achieved over the last years in terms of radiation hygiene in the field of imaging technology applied for medical diagnostics. The data obtained from four hospital centers (2 university hospitals, 1 city hospital, and one county hospital) and from three medical practices (radiologist, internal specialist, orthopedics), the changes experienced in the selection of imaging methods for diagnostic purposes in the period 1976 to 1983 or 1985 are illustrated, and analyses show the developmental trends. The results show that there is reason to assume the radiation exposure of the population to be receding. (orig./MG)

  9. Measurement of soil moisture using remote sensing multisensor radiation techniques

    Science.gov (United States)

    Waite, W. P. (Principal Investigator)

    1982-01-01

    Theoretical modeling as well as laboratory and field measurement were coupled with analysis of aircraft data obtained from controlled sites in an effort to enhance understanding of the microwave response due to soil moisture so as to specify sensor parameters and develop inversion algorithms. Models to predict the complex dielectric constant were produced which led to the interpretation of the results in terms of a matrix potential rather than simply moisture content. Similar advances were made in the development of coherent and incoherent radiative transfer models and rough surface scattering models.

  10. Radiodiagnostic measurements radiation load of children by chest

    International Nuclear Information System (INIS)

    In the district of Slovak Republic we have tried to estimate the radiation load of children to 15 years by chest radiodiagnostic examinations. Our data were collected using measurements with TLD for 100 patients divided in 5 age categories at six radiodiagnostic departments. The analysis of obtained absorbed doses as a function of age for chest radiodiagnostic examinations has shown, that the investigated Slovak radiodiagnostic centres use rather lower voltage techniques and the entrance surface doses are much higher than the proposed value of European Communities. (authors)

  11. Preliminary measurements of gamma radiation in Chilean Antarctic Stations

    International Nuclear Information System (INIS)

    Natural and artificial gamma radiation, 1 m above the soil, is being investigated in 4 Chilean Antartic Stations. The measurements are performed with different types of TLD detectors. Preliminary results in the Tte. Marsh Station are reported and discussed. An average exposition of 3,5 μR/h was found during a 108 days period. This exposition corresponds to an annual dose of about 40 mrad, 8% of the annual dose limit for individual of the public. The presence of low energy artificial radioisotopes was not found. (Author)

  12. Multichannel bolometer for radiation measurements on the TCA tokamak

    International Nuclear Information System (INIS)

    A multichannel radiation bolometer has been developed for the Tokamak Chauffage Alfven (TCA) tokamak. It has 16 equally spaced chords that view the plasma through a narrow horizontal slit. Almost an entire vertical plasma cross section can be observed. The bolometer operates on the basis of a semiconducting element which serves as a temperature-dependent resistance. A new electronic circuit has been developed which takes advantage of the semiconductor characteristics of the detector by using feedback techniques. Measurements made with this instrument are discussed

  13. Coherent diffraction radiation interferometry and short bunch length measurements

    International Nuclear Information System (INIS)

    The promising approach to measure a length of subpicosecond electron bunch is connected with measurements of coherent diffraction radiation (CDR) spectra due to strong dependence of the spectrum shape on the bunch length σz in the wavelength region λ ∼ σz [Proceedings of the International Symposium on New Visions in Laser-Beam Interactions, Nucl. Instr. and Meth. A 455 (1) (2000)]. The spectral measurements may be carried out by using an interferometer or a polychromator. The alternative approach for similar measurements is proposed in the paper. The interference pattern from two shifted halves of a CDR target may be used for this aim. If the broadband detector measures a CDR yield around λ0 ∼ σz then moving one half of the CDR target relative to other (parallel to beam) in the range of a few bunch lengths one can obtain the detuning curve (interferogram). The shape of detuning curve and its connection with bunch length is calculated for different detector apertures and detector waveband. The proposed technique may open the new possibility for non-invasive bunch length measurements in the subpicosecond range

  14. Visualization of Radiation Environment on Mars: Assessment with MARIE Measurements

    Science.gov (United States)

    Saganti, P.; Cucinotta, F.; Zeitlin, C.; Cleghorn, T.; Flanders, J.; Riman, F.; Hu, X.; Pinsky, L.; Lee, K.; Anderson, V.; Atwell, W.; Turner, R.

    2003-01-01

    For a given GCR (Galactic Cosmic Ray) environment at Mars, particle flux of protons, alpha particles, and heavy ions, are also needed on the surface of Mars for future human exploration missions. For the past twelve months, the MARJE (Martian Radiation Environment Experiment) instrument onboard the 200J Mars Odyssey has been providing the radiation measurements from the Martian orbit. These measurements are well correlated with the HZETRN (High Z and Energy Transport) and QMSFRG (Quantum Multiple-Scattering theory of nuclear Fragmentation) model calculations. These model calculations during these specific GCR environment conditions are now extended and transported through the CO2 atmosphere onto the Martian surface. These calculated pa11icle flux distributions are presented as a function of the Martian topography making use of the MOLA (Mars Orbiter Laser Altimeter) data from the MGS (Mars Global Surveyor). Also, particle flux calculations are presented with visualization in the human body from skin depth to the internal organs including the blood-forming organs.

  15. Protecting agriculture against nuclear radiations: conception and measures

    International Nuclear Information System (INIS)

    In case of atomic and chemical (AC) accident or attacks the agriculture is severely affected. This became clearly after the Chernobyl disaster, after which the authorities mobilized and increased the efforts to protect the agriculture. In Switzerland the Federal Commission for AC protection has undertaken the necessary actions in collaboration with the Federal Office for Agriculture. The protection of agriculture against radioactive fallout has many aspects. One of these concerns the requirement of informing farmers with all the necessary instruction to ensure the protection of rural population and animals, foods and forages, to make them able to take essential protection measures without exterior assistance, and to provide the agriculture buildings with simple and durable tools necessary in case of emergency intervention. To implement these requirements on Confederation level educational programs were developed to instruct agriculture agents and advisors on basic notions of radioactivity and radiation protection. These programs are thought to make the farmer aware with the implications of nuclear chemical and nuclear menace and the measures of protecting its enterprise by own means. Special instructions are to be applied by the enterprise chiefs to ensure first that the personnel protection is the top priority and then how to minimize and limit the damage produced by the radiation accident

  16. Visualization of radiation environment on Mars: assessment with MARIE measurements

    International Nuclear Information System (INIS)

    Full text: For a given GCR (Galactic Cosmic Ray) environment at Mars, particle flux of protons, alpha particles, and heavy ions, are also needed on the surface of Mars for future human exploration missions. For the past twelve months, the MARIE (Martian Radiation Environment Experiment) instrument onboard the 2001 Mars Odyssey has been providing the radiation measurements from the Martian orbit. These measurements are well correlated with the HZETRN (High Z and Energy Transport) and QMSFRG (Quantum Multiple-Scattering theory of nuclear Fragmentation) model calculations. These model calculations during these specific GCR environment conditions are now extended and transported through the CO2 atmosphere onto the Martian surface. These calculated particle flux distributions are presented as a function of the Martian topography making use of the MOLA (Mars Orbiter Laser Altimeter) data from the MGS (Mars Global Surveyor). Also, particle flux calculations are presented with visualization in the human body from skin depth to the internal organs including the blood-forming organs

  17. Smart measurement system for an environmental radiation monitoring

    International Nuclear Information System (INIS)

    A smart measurement system for an on-line gamma monitoring has been developed to overcome the problems of a conventional system which cannot automatically restore the previous-lost data of several posts by a radio telemetry. It is similar to the conventional system except for a new electronic circuit board and an integrated operation program. The new electronic circuit board is able to store the radiation data with a time tag of 6 or more months if the recording interval time is 10 s. The operation program automatically sends the time correction command to the six monitoring posts for a daily synchronization between the monitoring posts and the central control computer as a Korean mean time. The previous-lost radiation data for 6 or more months could be restored by using two components with the functions of a time tag and a daily synchronization without any additional equipment. It was tested for more than 1 year, from which the test results, the data collection rate was dramatically improved without any tedious manual work, which was almost about 100% for 1 year. The smart measurement system has been applied for an effective gamma monitoring around the nuclear facilities at KAERI since it was developed and tested in 2003

  18. Martian Radiation Environment: Model Calculations and Recent Measurements with "MARIE"

    Science.gov (United States)

    Saganti, P. B.; Cucinotta, F. A.; zeitlin, C. J.; Cleghorn, T. F.

    2004-01-01

    The Galactic Cosmic Ray spectra in Mars orbit were generated with the recently expanded HZETRN (High Z and Energy Transport) and QMSFRG (Quantum Multiple-Scattering theory of nuclear Fragmentation) model calculations. These model calculations are compared with the first eighteen months of measured data from the MARIE (Martian Radiation Environment Experiment) instrument onboard the 2001 Mars Odyssey spacecraft that is currently in Martian orbit. The dose rates observed by the MARIE instrument are within 10% of the model calculated predictions. Model calculations are compared with the MARIE measurements of dose, dose-equivalent values, along with the available particle flux distribution. Model calculated particle flux includes GCR elemental composition of atomic number, Z = 1-28 and mass number, A = 1-58. Particle flux calculations specific for the current MARIE mapping period are reviewed and presented.

  19. Environmental assessment for the Atmospheric Radiation Measurement (ARM) Program: Southern Great Plains Cloud and Radiation Testbed (CART) site

    International Nuclear Information System (INIS)

    The Atmospheric Radiation Measurement (ARM) Program is aimed at supplying improved predictive capability of climate change, particularly the prediction of cloud-climate feedback. The objective will be achieved by measuring the atmospheric radiation and physical and meteorological quantities that control solar radiation in the earth's atmosphere and using this information to test global climate and related models. The proposed action is to construct and operate a Cloud and Radiation Testbed (CART) research site in the southern Great Plains as part of the Department of Energy's Atmospheric Radiation Measurement Program whose objective is to develop an improved predictive capability of global climate change. The purpose of this CART research site in southern Kansas and northern Oklahoma would be to collect meteorological and other scientific information to better characterize the processes controlling radiation transfer on a global scale. Impacts which could result from this facility are described

  20. Environmental assessment for the Atmospheric Radiation Measurement (ARM) Program: Southern Great Plains Cloud and Radiation Testbed (CART) site

    Energy Technology Data Exchange (ETDEWEB)

    Policastro, A.J.; Pfingston, J.M.; Maloney, D.M.; Wasmer, F.; Pentecost, E.D.

    1992-03-01

    The Atmospheric Radiation Measurement (ARM) Program is aimed at supplying improved predictive capability of climate change, particularly the prediction of cloud-climate feedback. The objective will be achieved by measuring the atmospheric radiation and physical and meteorological quantities that control solar radiation in the earth`s atmosphere and using this information to test global climate and related models. The proposed action is to construct and operate a Cloud and Radiation Testbed (CART) research site in the southern Great Plains as part of the Department of Energy`s Atmospheric Radiation Measurement Program whose objective is to develop an improved predictive capability of global climate change. The purpose of this CART research site in southern Kansas and northern Oklahoma would be to collect meteorological and other scientific information to better characterize the processes controlling radiation transfer on a global scale. Impacts which could result from this facility are described.

  1. Radiation protection measures during the decommissioning of DR 2

    International Nuclear Information System (INIS)

    DR 2 (Danish Reactor 2), one of the research reactors at the Riso site, has been in the process of being decommissioned during the last two years. The decommissioning will be completed in 2008. The reactor went critical for the first time in late 1958 and was shut down in 1975. The construction was a 5 MW light-water moderated and cooled tank type reactor. Although the process of decommissioning was formally initiated in 2005, it was preceded by a characterization project with the purpose of determining activity contents in key materials and dose rates at relevant spots in the reactor. The paper describes the removal of neutron beam plugs, grid plate and a thermal column with focus on radiation protection issues. The primary objective is, however, to describe the measures taken to control radiation doses during the removal of the reactor block concrete and the reactor tank.The demolition and removal of concrete was done by an external contractor. The contractor had to comply with a comprehensive set of requirements. This included splitting activated concrete from concrete containing activities below clearance levels with no use of fluids of any kind, as the risk of not being able to control diffusion of contaminated fluids was an important issue. The experience from the decommissioning of the DR 1 reactor in 2005 showed that water-cooled cutting made it very difficult to monitor the levels of air contamination as the filters of the air monitors were blocked frequently. Certainly, dry cutting turned out to be a great technical challenge to the external contractor. Another demand was that the work should take place inside a de-pressurized containment in order to control air contamination and thereby minimize internal doses. The experience gathered from the practical implementation of dose reducing measures will be discussed. Problems involving the use of external contractors will be discussed, including training of personnel with no prior knowledge of radioactivity

  2. Testing of environmental radiation monitors using the Risø low-level radiation measurement stations

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.

    2000-01-01

    simulation of a radioactive plume passing over the monitors during a certain time was made using a specially designed source set up in the field that was able to vary the air kerma rate from low activity Cs-137 sources additional to the natural air kerma rate. It is demonstrated that a typical environmental......, Physikalisch Technische Bundesanstalt (Germany) and the Riso National Laboratory (Denmark). This paper describes the free-field irradiation facilities at Rise and some details of the field intercomparison experiments performed at the Riso Natural Environmental Radiation Measurement Station during 3rd and 4th...

  3. Development of radiation detection and measurement system - Development of scintillation radiation sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hee Dong; Kim, Wan [Kyungpook National University, Taegu (Korea); Kim, Do Sung [Taegu University, Taegu (Korea)

    2000-03-01

    We have been fabricated CsI(Tl) scintillation crystals and plastic scintillators for radiation-based measuring equipment. CsI (Tl) single crystals doped with thallium as an activator were grown using the Czochralski method. The crystal structure of grown CsI(Tl) was bcc, and it was confirmed that its lattice constant was 4,568 A. The spectral range of luminescence of CsI(Tl) was 350 {approx} 700 nm independent of thallium concentration, and the fast component of the luminescence was decreased with increasing thallium concentration. The energy resolution of CsI(Tl) scintillator doped with 0.1 mole% thallium was about 9% for 137 Cs {gamma}-rays. The relation formula of {gamma}-ray energy versus energy resolution was ln(FWHM%)=-0.705ln({epsilon})+6.75. The radiation damage of CsI(Tl) increased in proportion to thallium concentration and radiation damage of CsI(Tl) increased in proportion to thallium concentration and radiation dosage, and the irradiated crystals were colored reddish. The radiation induced absorption bands appeared around 355, 425, 520 and 555 nm, and their energy level were about 3.50, 2.88, 2.39 and 2.21 eV. Plastic scintillators were fabricated thermal polymerization method. Those were polymerizing at 120 deg. C, during 72 hours, and annealing at 75 deg. C, during 24 hours. When the concentration of 1st solute was 1.5 wt% and concentration of 2nd solute was 0.01 wt%, the characteristics of scintillation were very excellent. Also 3.0 wt% tetraphenyl lead were loaded to improve the detection efficiency of {gamma}-ray. The range of emission spectrum was 400 {approx} 450nm, and the central peak was 415 nm. The radiation damage was not appear under 1*10{sup 3}Gy, but the color of plastic scintillator was changed to brown, over 1*10{sup 4}Gy exposured. 84 refs., 39 figs. (Author)

  4. Atmospheric radiation measurement program facilities newsletter, April 2001.; TOPICAL

    International Nuclear Information System (INIS)

    Intensive Observation Period Projects Scheduled-Several IOP projects have been scheduled for the SGP CART site this spring. These projects either have already begun or will begin shortly. Radiosondes-The RS-90 Transition IOP is currently under way. The RS-90 model radiosonde is gradually replacing the older RS-80 model. Radiosondes are instrument packages attached to and launched by weather balloons. The instruments measure atmospheric pressure, temperature, and relative humidity as the balloon rises through the air. The new RS-90 model is a high-performance radiosonde with fast-response sensors capable of providing data for each variable every second. The relatively environmentally friendly package is constructed of cardboard and steel rather than Styrofoam, and it has a water-activated battery that contains no toxic substances. The RS-90 Transition IOP is taking place during April. Operators will launch both the old RS-80 and the new RS-90 radiosondes simultaneously once each day to obtain duplicate vertical profiles of the atmosphere for comparison. This procedure will also allow data users to test the output from the old and new radiosondes in models. Narrow Field of View (NFOV) Solar Spectrometer Cloud Optical Depth Retrieval Campaign-The NFOV IOP is scheduled to take place on May 7-August 31, 2001. A researcher from Pennsylvania State University will be deploying a dual-spectrometer instrument that measures the hemispheric flux and zenith NFOV radiance over a wavelength range of 300- 1000 nanometers. (One nanometer equals 1 billionth of a meter or 0.000000039 inches.) This wavelength range includes the ultraviolet, visible, and near-infrared spectra. These measurements are used to estimate cloud optical depth-a quantity related to the amount of solar radiation intercepted by a cloud-for broken cloud fields over vegetated surfaces. The IOP measurements will be compared with optical depth measurements made by SGP instruments. Precision Gas Sampling (PGS

  5. Dose measurements in pulsed radiation fields with commercially available measuring components

    International Nuclear Information System (INIS)

    Dose measurements in pulsed radiation fields with dosemeters using the counting technique are known to be inappropriate. Therefore, there is a demand for a portable device able to measure the dose in pulsed radiation fields. As a detector, ionisation chambers seem to be a good alternative. In particular, using a secondary standard ionisation chamber in combination with a reliable charge-measuring system would be a good solution. The Physikalisch-Technische Bundesanstalt (PTB) uses secondary standard ionisation chambers in combination with PTB-made measuring electronics for dose measurements at its reference fields. However, for general use, this equipment is too complex. For measurements on-site, a mobile special electronic system [Hupe, O. and Ankerhold, U. Determination of ambient and personal dose equivalent for personnel and cargo security screening. Radiat. Prot. Dosim. 121(4), 429-437 (2006)] has been used successfully. Still, for general use, there is a need for a much simpler but a just as good solution. A measuring instrument with very good energy dependence for H*(10) is the secondary standard ionisation chamber HS01. An easy-to-use and commercially available electrometer for measuring the generated charges is the UNIDOS by PTW Freiburg. Depending on the expected dose values, the ionisation chamber used can be selected. In addition, measurements have been performed by using commercially available area dosemeters, e.g. the Mini SmartION 2120S by Thermo Scientific, using an ionisation chamber and the Szintomat 6134 A/H by Automess, using a scintillation detector. (authors)

  6. Dose measurements in pulsed radiation fields with commercially available measuring components.

    Science.gov (United States)

    Friedrich, Sabrina; Hupe, Oliver

    2016-03-01

    Dose measurements in pulsed radiation fields with dosemeters using the counting technique are known to be inappropriate. Therefore, there is a demand for a portable device able to measure the dose in pulsed radiation fields. As a detector, ionisation chambers seem to be a good alternative. In particular, using a secondary standard ionisation chamber in combination with a reliable charge-measuring system would be a good solution. The Physikalisch-Technische Bundesanstalt (PTB) uses secondary standard ionisation chambers in combination with PTB-made measuring electronics for dose measurements at its reference fields. However, for general use, this equipment is too complex. For measurements on-site, a mobile special electronic system [Hupe, O. and Ankerhold, U. Determination of ambient and personal dose equivalent for personnel and cargo security screening. Radiat. Prot. Dosim. 121: (4), 429-437 (2006)] has been used successfully. Still, for general use, there is a need for a much simpler but a just as good solution. A measuring instrument with very good energy dependence for H*(10) is the secondary standard ionisation chamber HS01. An easy-to-use and commercially available electrometer for measuring the generated charges is the UNIDOS by PTW Freiburg. Depending on the expected dose values, the ionisation chamber used can be selected. In addition, measurements have been performed by using commercially available area dosemeters, e.g. the Mini SmartION 2120S by Thermo Scientific, using an ionisation chamber and the Szintomat 6134 A/H by Automess, using a scintillation detector. PMID:26056377

  7. Measurements of the thermal radiative properties of liquid uranium

    International Nuclear Information System (INIS)

    Measurements of the thermal radiative properties of liquid uranium have been made using an instrument with two optical systems, one for measuring the complex index of refraction by ellipsometry, the other for measuring the normal spectral emissivity by direct comparison to an integral blackbody cavity. The measurements cover the wavelength range 0.4 to 10 μm with sample temperatures between 940 and 1630 K. Two 5keV ion sputter guns and an Auger spectrometer produce and verify, in-situ, atomically pure sample surfaces. Good agreement between the two methods is observed for the normal spectral emissivity, which varies with wavelength in a manner typical of transition metals. The two components of the complex index of refraction, the index of refraction and the extinction coefficient, increase with wavelength, from ∼3 at 0.4 μm to -20 at 9.5 μm. Both components of polarized reflectivity are shown for visible to infrared wavelengths

  8. Detailed Evaluation of MODIS Fire Radiative Power Measurements

    Science.gov (United States)

    Ichoku, Charles

    2010-01-01

    Satellite remote sensing is providing us tremendous opportunities to measure the fire radiative energy (FRE) release rate or power (FRP) from open biomass burning, which affects many vegetated regions of the world on a seasonal basis. Knowledge of the biomass burning characteristics and emission source strengths of different (particulate and gaseous) smoke constituents is one of the principal ingredients upon which the assessment, modeling, and forecasting of their distribution and impacts depend. This knowledge can be gained through accurate measurement of FRP, which has been shown to have a direct relationship with the rates of biomass consumption and emissions of major smoke constituents. Over the last decade or so, FRP has been routinely measured from space by both the MODIS sensors aboard the polar orbiting Terra and Aqua satellites, and the SEVIRI sensor aboard the Meteosat Second Generation (MSG) geostationary satellite. During the last few years, FRP has been gaining recognition as an important parameter for facilitating the development of various scientific studies relating to the quantitative characterization of biomass burning and their emissions. Therefore, we are conducting a detailed analysis of the FRP products from MODIS to characterize the uncertainties associated with them, such as those due to the MODIS bow-tie effects and other factors, in order to establish their error budget for use in scientific research and applications. In this presentation, we will show preliminary results of the MODIS FRP data analysis, including comparisons with airborne measurements.

  9. Dense and narrow rings discovered around the Centaur object (10199) Chariklo

    Science.gov (United States)

    Sicardy, B.; Braga-Ribas, F.; Benedetti-Rossi, G.; Ligier, N.; Maquet, L.; Roques, F.; Leiva Espinoza, R.; El Moutamid, M.; Duffard, R.; Morales, N.; Ortiz, J. L.; Snodgrass, C.; Skottfelt, J.; Harpsøe, K.; Jørgensen, U. G.; Jehin, E.; Pollock, J.; Assafin, M.; Camargo, J.; Desmars, J.; Vieira-Martins, R.; Dumas, C.; Ivanov, V.; Maury, A.; Korhonen, H.; Leitzinger, M.

    2014-07-01

    A stellar occultation observed on June 3, 2013 revealed the unexpected presence of two dense rings around (10199) Chariklo [1], the largest Centaur object known to date with a radius of 124±9 km [2]. The two rings have respective orbital radii, widths, and normal optical depths of a_1= 391 km, W_1= 7 km, τ_1= 0.4 and a_2= 405 km, W_2= 3 km, τ_2= 0.06 [1]. They are separated by a gap of about 9 km with an optical depth less than 0.004 (1-sigma limit). The presence of those rings has been confirmed during another stellar occultation observed from ESO/NTT La Silla, ESO/VLT Paranal and San Pedro de Atacama on February 16, 2014. More results on the azimuthal variations of the rings and mass estimations of their putative shepherding satellites will be presented. This is the first ring system ever observed that does not pertain to a giant planet. The existence of such a system raises several questions as to the origin and evolution of rings around such a small object. This discovery also suggests that rings may be a more frequent feature than previously thought, in particular, around small bodies. Possible models for the ring formation will be proposed. They can be classified into collisional scenarios that disrupted an impactor or a pre-existing satellite, tidal disruption of an inward-migrating satellite, or material produced by a cometary activity of the central body.

  10. Calculation of undulator radiation from measured magnetic fields and comparison with measured spectra

    International Nuclear Information System (INIS)

    A new code was developed that calculates the spectrum, the state and the degree of polarization of the radiation emitted by any insertion device. It integrates along an arbitrary electron trajectory without any approximations. The trajectory can be derived either from a model undulator including random field errors or from a measured field distribution from a real undulator. The calculated one-electron pattern is convoluted with the electron beam emittance. Spectral calculations for the crossed field undulator U-2 at BESSY employing measured magnetic field data agree with absolute measurements of the spectra. (author) 18 refs.; 1 fig

  11. High beta radiation exposure of medical staff measures for optimisation of radiation protection

    International Nuclear Information System (INIS)

    Full text of publication follows: New therapies applying beta radionuclides have been introduced in medicine in recent years, especially in nuclear medicine, e. g. radio-synoviorthesis, radioimmunotherapy and palliative pain therapy. The preparation of radiopharmaceuticals, their dispensary as well as injection require the handling of vials and syringes with high activities of beta emitters at small distances to the skin. Thus the medical staff may be exposed to a high level of beta radiation. Hence the local skin dose, Hp(0,07), was measured at these workplaces with thin-layer thermoluminescent dosemeters TLD (LiF:Mg,P,Cu) fixed to the tip of the fingers at both hands of the personnel. In addition, official beta/photon ring dosemeters were worn at the first knuckle of the index finger. Very high local skin doses were measured at the tip of index finger and thumb. The findings indicate that the exposure of the staff can exceed the annual dose limit for skin of 500 mSv when working at a low protection standard. By the use of appropriate shieldings and tools (e.g. tweezers or forceps) the exposure was reduced of more than one order of magnitude. The German dosimetry services provide official beta/photon ring dosemeters for routine monitoring of the extremity exposure of occupationally exposed persons. But even monitoring with these official dosemeters does not provide suitable results to control compliance with the dose limit in the majority of cases because they can mostly not be worn at the spot of highest beta exposure (finger tip). Therefore, a study was performed to identify the difference of readings of official ring dosemeters and the maximum local skin dose at the finger tips. At workplaces of radio-synoviorthesis a correction factor of 3 was determined provided that the staff worked at high radiation protection standard and the ring dosemeters were worn at the first knuckle of the index finger. The correction factor increases significantly when the radiation

  12. Atmospheric Radiation Measurement Climate Research Facility (ACRF) Annual Report 2007

    Energy Technology Data Exchange (ETDEWEB)

    LR Roeder

    2007-12-01

    This annual report describes the purpose and structure of the program, and presents key accomplishments in 2007. Notable achievements include: • Successful review of the ACRF as a user facility by the DOE Biological and Environmental Research Advisory Committee. The subcommittee reinforced the importance of the scientific impacts of this facility, and its value for the international research community. • Leadership of the Cloud Land Surface Interaction Campaign. This multi-agency, interdisciplinary field campaign involved enhanced surface instrumentation at the ACRF Southern Great Plains site and, in concert with the Cumulus Humilis Aerosol Processing Study sponsored by the DOE Atmospheric Science Program, coordination of nine aircraft through the ARM Aerial Vehicles Program. • Successful deployment of the ARM Mobile Facility in Germany, including hosting nearly a dozen guest instruments and drawing almost 5000 visitors to the site. • Key advancements in the representation of radiative transfer in weather forecast models from the European Centre for Medium-Range Weather Forecasts. • Development of several new enhanced data sets, ranging from best estimate surface radiation measurements from multiple sensors at all ACRF sites to the extension of time-height cloud occurrence profiles to Niamey, Niger, Africa. • Publication of three research papers in a single issue (February 2007) of the Bulletin of the American Meteorological Society.

  13. Surface shortwave aerosol radiative forcing during the Atmospheric Radiation Measurement Mobile Facility deployment in Niamey, Niger

    Science.gov (United States)

    McFarlane, S. A.; Kassianov, E. I.; Barnard, J.; Flynn, C.; Ackerman, T. P.

    2009-07-01

    The Atmospheric Radiation Measurement (ARM) Program's Mobile Facility (AMF) was deployed to Niamey, Niger, during 2006. Niamey, which is located in sub-Saharan Africa, is affected by both dust and biomass burning emissions. Column aerosol optical properties were derived from multifilter rotating shadowband radiometer, measurements and the vertical distribution of aerosol extinction was derived from a micropulse lidar during the two observed dry seasons (January-April and October-December). Mean aerosol optical depth (AOD) and single scattering albedo (SSA) at 500 nm during January-April were 0.53 ± 0.4 and 0.94 ± 0.05, while during October-December mean AOD and SSA were 0.33 ± 0.25 and 0.99 ± 0.01. Aerosol extinction profiles peaked near 500 m during the January-April period and near 100 m during the October-December period. Broadband shortwave surface fluxes and heating rate profiles were calculated using retrieved aerosol properties. Comparisons for noncloudy periods indicated that the remote sensing retrievals provided a reasonable estimation of the aerosol optical properties, with mean differences between calculated and observed fluxes of less than 5 W m-2 and RMS differences less than 25 W m-2. Sensitivity tests showed that the observed fluxes could be matched with variations of aerosol radiative forcing (ARF) was -21.1 ± 14.3 W m-2 and was estimated to account for 80% of the total radiative forcing at the surface. The ARF was larger during January-April (-28.5 ± 13.5 W m-2) than October-December (-11.9 ± 8.9 W m-2).

  14. The possible direct use of satellite radiance measurements by the Atmospheric Radiation Measurement Program

    International Nuclear Information System (INIS)

    The Atmospheric Radiation Measurement (ARM) Program is a major research program initiated by the Department of Energy to improve our understanding of radiative and cloud processes critical to predicting the Earth's climate and its changes. Central to this concept is the use of four to six intensively instrumented sites for long-term study and characterization of the processes of interest. The instrumentation suites will include ground-based, high-accuracy radiometers for measuring the short and longwave surface flux, as well as an extensive set of ground-and air-based instrumentation for characterizing the intervening atmospheric column. Satellite-based measurements are expected to play a very important role in providing top-of-the-atmosphere measurements. In this study, we examine the possibility of comparing ARM outputs directly with satellite measurements, thereby ensuring the independence of these two important data sets. Thus we focused on what do satellites really measure and how well do they measure it. On what can we do about the general lack of adequate visible channel calibration. On what is the best way for ARM to obtain near-real-time access to this unprocessed data. And on what is the optimum way for ARM to make use of satellite data

  15. Development of a radiation measurement system based on radiation and heat resistant materials

    International Nuclear Information System (INIS)

    This paper explains the following themes that Hokkaido University is currently promoting as a core agent, (1) development of diamond semiconductor device for nuclear reactors with the aim of severe accident countermeasure, and (2) development of an underlying technology for portable energy differentiation and position detective α-ray measuring device. The theme (1) is the attempt of developing diamond semiconductor device for use in the equipment used in a reactor containment vessel, which faces increasing demands for very tough resistance against radiation and high-temperatures after the Fukushima Daiichi Nuclear Power Station accident. The development of diamond FET that works stably at 500degC was successfully made, and a diamond detector for γ-rays has come to satisfy the performance demands such as 300degC or above, 5 MGy, and dynamic range of 7-digits. The theme (2) is the development of an underlying technology for scintillator-based portable energy differentiation and position detective α-ray measurement device for use in the in-situ measurement of α-ray emitting nuclei originated from nuclear fuel such as 238Pu, under high γ-ray and β-ray background, which is required in environmental measurement and decommissioning work. The development of the device capable of discriminating Pu of 0.37 Bq within 5 min under the environment of Pu: Rn progeny nuclei abundance ratio = 1: 100 was successfully made. Both projects are based on the development of the materials that can withstand both harsh radiation and high-temperature environments. (author)

  16. Measurement of synchrotron-radiation-excited Kossel patterns.

    Science.gov (United States)

    Bortel, G; Faigel, G; Tegze, M; Chumakov, A

    2016-01-01

    Kossel line patterns contain information on the crystalline structure, such as the magnitude and the phase of Bragg reflections. For technical reasons, most of these patterns are obtained using electron beam excitation, which leads to surface sensitivity that limits the spatial extent of the structural information. To obtain the atomic structure in bulk volumes, X-rays should be used as the excitation radiation. However, there are technical problems, such as the need for high resolution, low noise, large dynamic range, photon counting, two-dimensional pixel detectors and the small spot size of the exciting beam, which have prevented the widespread use of Kossel pattern analysis. Here, an experimental setup is described, which can be used for the measurement of Kossel patterns in a reasonable time and with high resolution to recover structural information. PMID:26698066

  17. Measurement and analysis of coherent synchrotron radiation effects at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Beutner, B.

    2007-12-15

    The vacuum-ultra-violet Free Electron Laser in Hamburg (FLASH) is a linac driven SASE-FEL. High peak currents are produced using magnetic bunch compression chicanes. In these magnetic chicanes, the energy distribution along an electron bunch is changed by eff ects of Coherent Synchrotron Radiation (CSR). Energy changes in dispersive bunch compressor chicanes lead to transverse displacements along the bunch. These CSR induced displacements are studied using a transverse deflecting RF-structure. Experiments and simulations concerning the charge dependence of such transverse displacements are presented and analysed. In these experiments an over-compression scheme is used which reduces the peak current downstream the bunch compressor chicanes. Therefore other self interactions like space charge forces which might complicate the measurements are suppressed. Numerical simulations are used to analyse the beam dynamics under the influence of CSR forces. The results of these numerical simulations are compared with the data obtained in the over-compression experiments at FLASH. (orig.)

  18. Measurement of ionizing radiation using carbon nanotube field effect transistor

    International Nuclear Information System (INIS)

    Single-walled carbon nanotubes (SWNTs) are a new class of highly promising nanomaterials for future nano-electronics. Here, we present an initial investigation of the feasibility of using SWNT field effect transistors (SWNT-FETs) formed on silicon-oxide substrates and suspended FETs for radiation dosimetry applications. Electrical measurements and atomic force microscopy (AFM) revealed the intactness of SWNT-FET devices after exposure to over 1 Gy of 6 MV therapeutic x-rays. The sensitivity of SWNT-FET devices to x-ray irradiation is elucidated by real-time dose monitoring experiments and accumulated dose reading based on threshold voltage shift. SWNT-FET devices exhibit sensitivities to x-rays that are at least comparable to or orders of magnitude higher than commercial MOSFET (metal-oxide semiconductor field effect transistor) dosimeters and could find applications as miniature dosimeters for microbeam profiling and implantation. (note)

  19. Development of Spectrometer Software for Electromagnetic Radiation Measurement and Analysis

    International Nuclear Information System (INIS)

    This software was under development using LabVIEW to be using with StellarNet Spectrometer system. StellarNet Spectrometer was supplied with SpectraWiz operating software that can measure spectral data for real-time spectroscopy. This LabVIEW software was used to access real-time data from SpectraWiz dynamic link library as hardware interfacing. This software will acquire amplitude of every electromagnetic wavelength at periodic time. In addition to hardware interfacing, the user interface capabilities of software include plotting of spectral data in various mode including scope, absorbance, transmission and irradiance mode. This software surely can be used for research and development in application, utilization and safety of electromagnetic radiation, especially solar, laser and ultra violet. Of-line capabilities of this software are almost unlimited due to availability of mathematical and signal processing function in the LabVIEW add on library. (author)

  20. Measurement and analysis of coherent synchrotron radiation effects at FLASH

    International Nuclear Information System (INIS)

    The vacuum-ultra-violet Free Electron Laser in Hamburg (FLASH) is a linac driven SASE-FEL. High peak currents are produced using magnetic bunch compression chicanes. In these magnetic chicanes, the energy distribution along an electron bunch is changed by eff ects of Coherent Synchrotron Radiation (CSR). Energy changes in dispersive bunch compressor chicanes lead to transverse displacements along the bunch. These CSR induced displacements are studied using a transverse deflecting RF-structure. Experiments and simulations concerning the charge dependence of such transverse displacements are presented and analysed. In these experiments an over-compression scheme is used which reduces the peak current downstream the bunch compressor chicanes. Therefore other self interactions like space charge forces which might complicate the measurements are suppressed. Numerical simulations are used to analyse the beam dynamics under the influence of CSR forces. The results of these numerical simulations are compared with the data obtained in the over-compression experiments at FLASH. (orig.)

  1. Radiation dose measurement for patients and staff during cardiac catheterization

    International Nuclear Information System (INIS)

    The primary objective of this study was to determine the patient and staff dose during cardiac catheterization procedures in Ahmed Gasim Hospital, Khartoum Bahry. A survey of patient and staff exposure was performed covered 2 Cath Lab units from 2 manufacturers. The measurements involved 50 operations. The medical staff was monitored using TLD chips (LiF: Mg, Cu, P). The main operator who was closer to the patient and the x-ray tube, was monitored at six positions (forehead, neck chest - over the lead apron, waist - under the lead apron, leg, and hand), while the exposure to the assistant was measured at two positions (chest - over the lead apron, and hand), where the technologist and the circulator were monitored at one position (chest - over the lead apron). patient exposure was measured using the DAP meter. The main operator and the rest of the staff received 0.14, 0.01 mSv/y respectively. The estimated patient dose rate was found to be 125 mGy/min which considered higher than the recommended DRL for the continuous high mode fluoroscopy used in interventional radiology (100 mGy/min). The study concluded to the fact that the main operator received relatively high dose which is a direct result to the poor radiation protection in the department. (Author)

  2. Thermography research for radiation measurement on an oil spill fire

    International Nuclear Information System (INIS)

    Oil spill fire tests were conducted at Japan's Fire Research Institute 24x24-m indoor test facility and at the US Coast Guard 15x15-m vessel in Mobile, Alabama. Measurements of infrared energy emitted by the fires were made by high speed thermography, and these measurements were converted to temperature measurements by the instrument used. Results of average emissivity distribution from a 2.7 m square Arabian crude oil fire are presented. Most of the radiation comes from a very low part of the flame. In larger flames of a 15 m square fire, most of the flame surface was covered with cold smoke and height of the maximum emissivity was very low. Average flame emissivity was also very low. The maximum radiant emittance of flames and irradiance at the outside target was a maximum in 2-3 m of vessel diameter. In smaller fires, irradiance was smaller since the emissivity of the flame was less than 1; in larger fires, irradiance decreased as vessel diameter increased due to the smoke blockage effect. 12 refs., 4 figs., 3 tabs

  3. Experimentally Measured Radiative Lifetimes and Oscillator Strengths in Neutral Vanadium

    Science.gov (United States)

    Holmes, C. E.; Pickering, J. C.; Ruffoni, M. P.; Blackwell-Whitehead, R.; Nilsson, H.; Engström, L.; Hartman, H.; Lundberg, H.; Belmonte, M. T.

    2016-06-01

    We report a new study of the V i atom using a combination of time-resolved laser-induced fluorescence and Fourier transform spectroscopy that contains newly measured radiative lifetimes for 25 levels between 24,648 cm‑1 and 37,518 cm‑1 and oscillator strengths for 208 lines between 3040 and 20000 Å from 39 upper energy levels. Thirteen of these oscillator strengths have not been reported previously. This work was conducted independently of the recent studies of neutral vanadium lifetimes and oscillator strengths carried out by Den Hartog et al. and Lawler et al., and thus serves as a means to verify those measurements. Where our data overlap with their data, we generally find extremely good agreement in both level lifetimes and oscillator strengths. However, we also find evidence that Lawler et al. have systematically underestimated oscillator strengths for lines in the region of 9000 ± 100 Å. We suggest a correction of 0.18 ± 0.03 dex for these values to bring them into agreement with our results and those of Whaling et al. We also report new measurements of hyperfine structure splitting factors for three odd levels of V i lying between 24,700 and 28,400 cm‑1.

  4. PARduino: A Simple Device Measuring and Logging Photosynthetically Active Radiation

    Science.gov (United States)

    Barnard, H. R.; Findley, M. C.

    2013-12-01

    Photosynthetically Active Radiation (PAR, 400 to 700 nm) is one of the primary controls of forest carbon and water relations. In complex terrain, PAR has high spatial-variability. Given the high cost of commercial datalogging equipment, spatially-distributed measurements of PAR have been typically modeled using geographic coordinates and terrain indices. Here, we present a design for a low cost, field-deployable device for measuring and logging PAR built around an Arduino microcontroller (we named it PARduino). PARduino provides for widely distributed sensor arrays and tests the feasibility of using hobbyist-grade electronics for collecting scientific data. PARduino components include a LiCor quantum sensor, EME Systems signal converter/amplifier, and Sparkfun's Arduino Pro Mini microcontroller. Additional components include a real time clock, a microSD flash memory card, and a custom printed circuit board (PCB). We selected the components with an eye towards ease of assembly. Everything can be connected to the PCB using through-hole soldering techniques. Since the device will be deployed in remote research plots that lack easy access to line power, battery life was also a consideration in the design. Extended deployment is possible because PARduino's software keeps it in a low-power sleep mode until ready to make a measurement. PARduino will be open-source hardware for use and improvement by others.

  5. Application of Terahertz Radiation to Soil Measurements: Initial Results

    Directory of Open Access Journals (Sweden)

    Volker Dworak

    2011-10-01

    Full Text Available Developing soil sensors with the possibility of continuous online measurement is a major challenge in soil science. Terahertz (THz electromagnetic radiation may provide the opportunity for the measurement of organic material density, water content and other soil parameters at different soil depths. Penetration depth and information content is important for a functional soil sensor. Therefore, we present initial research on the analysis of absorption coefficients of four different soil samples by means of THz transmission measurements. An optimized soil sample holder to determine absorption coefficients was used. This setup improves data acquisition because interface reflections can be neglected. Frequencies of 340 GHz to 360 GHz and 1.627 THz to 2.523 THz provided information about an existing frequency dependency. The results demonstrate the potential of this THz approach for both soil analysis and imaging of buried objects. Therefore, the THz approach allows different soil samples to be distinguished according to their different absorption properties so that relations among soil parameters may be established in future.

  6. Measurement and simulation of TEPC microdosimetric spectra in gamma radiation field

    International Nuclear Information System (INIS)

    According to the different characteristics of microdosimetric spectra measured by tissue equivalent proportional counter (TEPC), the neutron dose equivalent and γ dose equivalent could be distinguished in a unknown neutron and γ mixed radiation field. In order to discriminate the γ radiation dose equivalent from the total value, the pure γ microdosimetric spectra was measured in 60Co, 137CS radionuclide radiation field with TEPC. TEPC microdosimetric spectra in a series of monoenergy γ radiation field were simulated by FLUKA code. All the γ radiation microdosimetric spectra, including measured spectrum in 60Co, 137CS radiation field and that of simulation spectrum by FLUKA code, reveal a trait that the linear energy of γ radiation is basically lower than 10 keV/μm. This trait is the very foundation to discriminate the γ radiation from the mixed radiation. (authors)

  7. Advances in traceability of solar ultraviolet radiation measurements

    International Nuclear Information System (INIS)

    Measurements of solar ultraviolet radiation (UVR) at STUK (Radiation and Nuclear Safety Authority, Finland) commenced in 1989, five years after the alarming observation of the ozone depletion in the Antarctic and in association with the establishment of the solar UV monitoring network of the Finnish Meteorological Institute. It was soon realised that the instrumentation for solar UVR measurements was far from adequate for the challenging task of measuring the solar UV spectrum. In addition, the intercomparison of lamps used as secondary standards of UV irradiance between the National Standard Laboratories revealed significant discrepancies. In the course of this study, a national lamp-based scale for UV irradiance was established by STUK and subsequently was confirmed with the detector-based scale of the Helsinki University of Technology (HUT). Methods for (i) radiometric testing, (ii) calibration and (iii) data correction were developed for solar UV spectroradiometers and for broadband erythemally weighted (EW) solar UV radiometers. A common opinion in the early 1990s was that EW radiometers were not good enough for solar UV monitoring; spectroradiometers or multi-channel narrow band radiometers were seen as the only option for reliable solar UV radiometry. Later on, several intercomparisons revealed that, without stringent methods of quality control (QC) and quality assurance (QA), even high precision spectroradiometers easily yield UV data erroneous by 20% or more. The reliability of the spectroradiometric solar UVR measurements made by STUK was verified in the Nordic solar UV radiometer intercomparisons in 1993 and 1996 and in the largest European intercomparison of solar UV spectroradiometers in 1997. At STUK, it was considered that the low cost and easy-to-operate EW radiometers also had a role in solar UV monitoring. After developing the calibration methods for EW radiometers and gaining experience in testing of 16 EW radiometers, STUK organised the first

  8. Abstracts from the fourth annual meeting of the council on ionizing radiation measurements and standards (CIRMS)

    International Nuclear Information System (INIS)

    The Council on Ionizing Radiation Measurements and Standards held its fourth annual meeting at the National Institute of Standards and Technology, Gaithersburg, Maryland on November 28-30, 1995. The organization represents thousands of users of ionizing radiation and radioactive sources engaged in industrial radiation processing and sterilization, medical radiation diagnostics and therapy, nuclear power, and worker radiation protection programs. CIRMS provides a forum for discussing ionizing radiation issues; identifying, defining and prioritizing needed work; disseminating information on standards; and organizing workshops and meetings to advance ionizing radiation technology. Over 100 participants attended the meeting, which highlighted advanced techniques in radiation dosimetry and radioactivity measurements for the different ionizing radiation communities. Representatives attended from 28 corporations, 10 federal agencies, 8 national laboratories, 12 universities, and 1 state. Advanced techniques and future measurement needs were discussed in four sessions: (I) Medical Dosimetry, Radiology and Nuclear Medicine, (II) Occupational and Radiation Protection Dosimetry, (III) Measurement Techniques for Public and Environmental Radiation Protection, and (IV) Measurement Techniques for Radiation Effects on Materials. An additional session (Session V) was added to this annual meeting on the implementation of ISO 9000 for those CIRMS members involved in instrument and product manufacturing, and those providing radiation measurement services. Abstracts are also included from the poster session (Session VI) held on the final day of the meeting. The 4th Annual Meeting was organized by the Chairman of the Science and Technology Committee, Mr. Joseph C. McDonald of the Battelle Pacific Northwest Laboratory

  9. Environmental radiation in Tokushima prefecture measured by driving survey

    International Nuclear Information System (INIS)

    The map of radiation dose rate distribution in Tokushima prefecture was depicted following the driving survey. Gamma ray rate at every 1 sec was measured in the car with NaI scintillation survey-meter 5000 Cypher (Toyo Medic), which was connected with personal computer to calculate the mean rate/10 sec. With GPS (GlobalSat DG-1000), the measuring route was identified; and the point/measured rate were matched with SONY IC recorder ICD-UX91. Driving was performed along national and prefectural roads to cover the whole area of Tokushima. Shielding effect of the car body and effect of the car speed were actually examined by measurement inside/outside of the car and by fixed point measuring in 1 min stop: 27.3% shielding and 79.8-111.4% fluctuation were found, respectively. The survey was conducted on fine days intermittently from May 2010 to June 2012. Although the Fukushima Nuclear Power Plant Accident (Mar 2011) had occurred during the survey period, its effect was not found in the prefectural publication: from June 13th to Dec 27th, 2011, means of monthly effective dose rate at 1 m height from the ground were in the range of 0.063-0.065 mc-Sv/h. This was also confirmed by authors' monthly survey on a same driving route from Mar 2011 to July 2012. The dose rate was found higher in mountains than in cities and differed dependently on geological strata and features. The rate in the prefecture was the highest at its southern area of Shimanto terrain. At plain regions on alluvium along the Yoshinogawa, the rate was low while high at regions on Izumi group located at north of the river. Mean dose rates in all of prefectural municipalities were thus available. (T.T.)

  10. Space charge dosimeters for extremely low power measurements of radiation in shipping containers

    Science.gov (United States)

    Britton, Jr.; Charles L.; Buckner, Mark A.; Hanson, Gregory R.; Bryan, William L.

    2011-04-26

    Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes in situ polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

  11. Manufacture of 60Co source irradiation facility and measurement of radiation filed

    International Nuclear Information System (INIS)

    60Co source radiation facility is an important equipment to produce reference radiation filed, according to national standard, the scattered dose rate must be less than 5% of the total dose rate in the reference radiation filed. Scattered radiation contribution and uniformity of reference radiation field are important parameters to describe the radiation performance of 60CO source irradiation device, Monte Carlo method was used to study the scattered radiation and uniformity of the reference radiation filed to provide theoretical basis for the design of 60CO source irradiating device in order to avoid economic losses caused by design mistakes. When 60CO source irradiating device was manufactured, PTW ionization chamber was used to measure the irradiation field. The results showed that the scattered radiation and uniformity of the radiation filed were in good agreement with the simulation results. The radiation performance met the design requirements. (authors)

  12. Noise Radiation Measure-Sound Power and its Test Methods

    Directory of Open Access Journals (Sweden)

    Zeng Xianren

    2013-06-01

    Full Text Available This study mainly aims to study the characteristics and theory of sound radiation of steady-state vibration. Study shows that sound radiation power of steady-state vibration is constant. And taking excavator for experimental object by hemisphere surface method, the radiated sound power of the excavator is the same as testing the sound pressure on various surfaces based on relevant international standard. Finally, a test method of radiated sound power for cylindrical vibration object is proposed.

  13. Some trial for reducing radiation doses at radiographic measurement of the pelvis

    International Nuclear Information System (INIS)

    The radiation doses were measured by TLD on the skin surface at the x-ray measurement of the pelvis and the following results were obtained. The radiation doses determined by either Martius of Guthmann method. By applying additional aluminum filters thickening between 0.5 mm and 1.0 mm, 50% of the radiation doses were reduced at radiation voltage of between 105 kv and 110 kv. (author)

  14. Human exposition to non ionizing electromagnetic radiations. Legislation and base stations measurements

    Directory of Open Access Journals (Sweden)

    Alonso Alonso Alonso

    2004-12-01

    Full Text Available This work deals about measurement procedures of non-ionizing radiations and their recorded levels in practice. The analyzed radiation sources cover the most common broadcasting media such as AM and FM transmissions and the GSM mobile telephony base stations. These sources currently radiate locations with high density of population. Spanish radiation level regulations are briefly described and some possible improvements are pointed out. The measurement results are discussed.

  15. Modular Architecture for the Measurement of Space Radiation

    Science.gov (United States)

    Delaune, Paul; Turner, Kathryn; Holland, S. Douglas; Carson, William R.; Riman, Fadi

    2007-01-01

    A modular architecture has been conceived for the design of radiation-monitoring instruments used aboard spacecraft and in planetary-exploration settings. This architecture reflects lessons learned from experience with prior radiation-monitoring instruments. A prototype instrument that embodies the architecture has been developed as part of the Mars Advanced Radiation Acquisition (MARA) project. The architecture is also applicable on Earth for radiation-monitoring instruments in research of energetic electrically charged particles and instruments monitoring radiation for purposes of safety, military defense, and detection of hidden nuclear devices and materials.

  16. Capillary acquisition devices for high-performance vehicles: Executive summary. [evaluation of cryogenic propellant management techniques using the centaur launch vehicle

    Science.gov (United States)

    Blatt, M. H.; Bradshaw, R. D.; Risberg, J. A.

    1980-01-01

    Technology areas critical to the development of cryogenic capillary devices were studied. Passive cooling of capillary devices was investigated with an analytical and experimental study of wicking flow. Capillary device refilling with settled fluid was studied using an analytical and experimental program that resulted in successful correlation of a versatile computer program with test data. The program was used to predict Centaur D-1S LO2 and LH2 start basket refilling. Comparisons were made between the baseline Centaur D-1S propellant feed system and feed system alternatives including systems using capillary devices. The preferred concepts from the Centaur D-1S study were examined for APOTV and POTV vehicles for delivery and round trip transfer of payloads between LEO and GEO. Mission profiles were determined to provide propellant usage timelines and the payload partials were defined.

  17. Radiation control and exposure reduction measures for special works in Japan Atomic Energy Research Institute

    International Nuclear Information System (INIS)

    Radiation protection of personnel in specific radioactive works involves the following matters: the facilities, equipments, and measuring instruments appropriate for the types and quantities of radioactive materials to be handled, the skills of personnel for handling radioactive materials, and the system of radiation safety management suitable for the scale of radiation works. The practices in this connection in JAERI are described: (1) the radiation control scheme including the management system and the control of radiation works; (2) radiation protection for the personnel by such as shielding, distance from radiation sources, and the removal of radiation sources; (3) the protective measures against contamination, in particular, the testing method of protective masks on the sites of radiation works and the estimation of the resuspension factor of radioactive dust deposit. (J.P.N.)

  18. Take a Geiger counter. Radiation measurement techniques in practice. Pt. 1

    International Nuclear Information System (INIS)

    Basic information is provided on radiation measurement techniques, along with general hints and recommendations to users and prospective buyers of radiation measurement devices. In particular the aims of radiation protection, state of the art, of measuring devices and units, measuring errors and verification limits, functional subassemblies, presentation of measuring values, operation, maintenance, and functional check-up of radiation protection devices are pointed out. The general remarks and hints regarding use and purchase of devices reflect all the experience accumulated by the author during several decades. (DG)

  19. Atmospheric radiation measurement program facilities newsletter, September 2001.; TOPICAL

    International Nuclear Information System (INIS)

    Our Changing Climate-Is our climate really changing? How do we measure climate change? How can we predict what Earth's climate will be like for generations to come? One focus of the Atmospheric Radiation Measurement (ARM) Program is to improve scientific climate models enough to achieve reliable regional prediction of future climate. According to the Environmental Protection Agency (EPA), the global mean surface temperature has increased by 0.5-1.0 F since the late 19th century. The 20th century's 10 warmest years all occurred in the last 15 years of the century, with 1998 being the warmest year of record. The global mean surface temperature is measured by a network of temperature-sensing instruments distributed around the world, including ships, ocean buoys, and weather stations on land. The data from this network are retrieved and analyzed by various organizations, including the National Aeronautics and Space Administration, the National Oceanic and Atmospheric Administration, and the World Meteorological Organization. Worldwide temperature records date back to 1860. To reconstruct Earth's temperature history before 1860, scientists use limited temperature records, along with proxy indicators such as tree rings, pollen records, and analysis of air frozen in ancient ice. The solar energy received from the sun drives Earth's weather and climate. Some of this energy is reflected and filtered by the atmosphere, but most is absorbed by Earth's surface. The absorbed solar radiation warms the surface and is re-radiated as heat energy into the atmosphere. Some atmospheric gases, called greenhouse gases, trap some of the re-emitted heat, keeping the surface temperature regulated and suitable for sustaining life. Although the greenhouse effect is natural, some evidence indicates that human activities are producing increased levels of some greenhouse gases such as carbon dioxide, methane, and nitrous oxide. Scientists believe that the combustion of fossil fuels is

  20. Sweat gland function as a measure of radiation change

    International Nuclear Information System (INIS)

    Radiotherapy may result in dryness of the skin even when no other change can be detected. We describe a system for recording the electrical conductance of skin as a measure of sweat gland function. In 22 normal volunteers close agreement was obtained between measurements obtained from comparable sites on both sides of the chest. Measurements were subsequently made in 38 patients treated by radiotherapy to one side of the chest for tumours of the breast or lung using one of five different fractionation schedules. Simultaneous readings were obtained from both sides of the chest with the non irradiated side acting as a control. A dose response relationship was demonstrated: five patients who received the equivalent total dose of 15 Gy in 2-Gy fractions showed no change in conductance. Sixteen out of 23 who received an equivalent total dose of 42-46 Gy in 2-Gy fractions had a greater than 22% reduction in mean skin conductance compared with that of the control areas despite the skin appearing normal in the large majority. Marked changes in skin conductance were seen after higher total doses. In a prospective study 18 women receiving breast irradiation underwent weekly readings during treatment. A mean reduction of 40% in skin conductance was noted by the end of the second week of treatment prior to any clinical evidence of radiation change. Skin conductance returned to normal in 44% of patients by 6 months. In the remainder, those patients who showed the greatest reduction in skin conductance during treatment demonstrated the least recovery. Changes in sweat gland function can be detected and quantified in skin which may otherwise appear normal. Differences may so be demonstrated between areas treated using different fractionation schedules and the method may be applied to the detection during radiotherapy of unusually sensitive patient. (author)

  1. Technology Development for Radiation Dose Measurement and Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong Hwan; Chang, S. Y.; Lee, T. Y. (and others)

    2007-06-15

    The correction factors essential for the operation of In-Vivo counting system were produced and implemented into a field operation for the improvement of accuracy in measurement of the radioactivity inside a human body. The BiDAS2007 code which calculate an internal dose was developed by upgrading the former code prepared in the previous stage of this project. The method of using the multibioassy data, the maximum likelihood function and the Bayesian statistics were established to an internal dose based on the measurement data of radioactivity, intakes and retention of radioactivity in a human body and it can improve the accuracy in estimation of the intakes of radioactivity and the committed effective dose equivalent. In order to solve the problem of low detection efficiency of the conventional Bonner Sphere (BS) to a high energy neutron, the extended BS's were manufactured and the technique for neutron field spectrometry was established. The fast neutron and gamma spectrometry system with a BC501A scintillation detector was also prepared. Several neutron fluence spectra at several nuclear facilities were measured and collected by using the extended BS. The spectrum weighted responses of some neutron monitoring instruments were also derived by using these spectra and the detector response functions. A high efficient TL material for the neutron personal dosimeter was developed. It solved the main problem of low thermal stability and high residual dose of the commercial TLDs and has the sensitivity to neutron and to gamma radiation with 40 and 10 times higher respectively than them.

  2. Automated Radiation Measurements for Aviation Safety (ARMAS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Commercial aircrew members and frequent flyers face radiation hazards from the effects of cosmic rays and solar energetic particles. During significant solar...

  3. Mars’ Surface Radiation Environment Measured with the Mars Science Laboratory’s Curiosity Rover

    OpenAIRE

    Hassler, D. M.; Zeitlin, C.; Wimmer-Schweingruber, R. F.; Ehresmann, B; Rafkin, S.; Eigenbrode, J. L.; Brinza, D.E.; Weigle, G.; Böttcher, S.; E. Böhm; Burmeister, S.; Guo, J.; Köhler, J.; Martin, C.; Reitz, G.

    2014-01-01

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory’s Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiat...

  4. The measurement technique of radiation shielding performance for hot cell walls in IMEF

    International Nuclear Information System (INIS)

    Hot cell is the facility to test irradiated materials. The capability of radiation shielding through wall should be conformed to protect the workers from expose. In this report, the measurement techniques of radiation shielding performance through hot cell walls are described. Detailed contents are as following; 1. The theory of test 2. The measuring equipment of radiations capability 3. The choice of measuring points 4. Test procedures and data analysis method 5. The reinforcement of shielding lack area. (author). 13 tabs., 19 figs

  5. Measurement of daily envvironmental radiation doses using hypersensitive thermoluminescence materials

    International Nuclear Information System (INIS)

    Lower detection limits below 1 μGy have been reported for the hypersensitive thermoluminescence phosphors such as LiF:Mg,P,Cu and α-Al2O3:C. Considering that usual daily environmental doses are in the range of 1-5 μGy, the CIEMAT Dosimetry Unit has designed an experiment to validate the real capability of these dosemeters to assess extremely low doses in two different environmental situations (indoor, outdoor). Three types of these phosphors (GR-200A from China, MCP-N from Poland, α-Al2O3:C from Russia) and one electronic dosemeter EPD from Siemens-Plessey have been studied. The experiment consisted of the determination of the integrated dose after exposure periods to environmental radiation ranging from one day to six months. These measurements were carried out with each one of the systems using a high pressure ionisation chamber as a reference instrument. The results demonstrate that the hypersensitive phosphors are capable of estimating these very low doses in agreement with the active detector. (Author)

  6. The Self And Beyond: A Reading of The Fixer, The Centaur, And Henderson The Rain King The Self And Beyond: A Reading of The Fixer, The Centaur, And Henderson The Rain King

    Directory of Open Access Journals (Sweden)

    Susana Bornéo Funck

    2009-09-01

    Full Text Available Toward the end of the three novels I'm going to discuss, the protagonists make the following statements. Eugene penderson, in Bellow's Henderson the Rain Xing, days: "Whatever gains I ever made were always due to love and nothing else." In Updike's The Centaur, George Caldwell realizes that "Only goodness lives. But it does live." And Yakov Bok in Malamud's The Fixer recognizes that "There's no such a thing as an unpolitical man." Isolated though they may be from the contexts in which they appear, these statements summarize appropriately enough the lessons learned by the three protagonists after periods of intense doubts and suffering. Toward the end of the three novels I'm going to discuss, the protagonists make the following statements. Eugene penderson, in Bellow's Henderson the Rain Xing, days: "Whatever gains I ever made were always due to love and nothing else." In Updike's The Centaur, George Caldwell realizes that "Only goodness lives. But it does live." And Yakov Bok in Malamud's The Fixer recognizes that "There's no such a thing as an unpolitical man." Isolated though they may be from the contexts in which they appear, these statements summarize appropriately enough the lessons learned by the three protagonists after periods of intense doubts and suffering.

  7. Status of radiation damage measurements in room temperature semiconductor radiation detectors

    International Nuclear Information System (INIS)

    The literature of radiation damage measurements on cadmium zinc telluride (CZT), cadmium telluride (CT), and mercuric iodide (HgI2) is reviewed for the purpose of determining their applicability to space applications. CZT strip detectors exposed to intermediate energy (1.3 MeV) proton fluences exhibit increased interstrip leakage after 1010 p/cm2 and significant bulk leakage after 1012 p/cm2. CZT exposed to 200 MeV protons shows a two-fold loss in energy resolution after a fluence of 5 x 109 p/cm2 in thick (3 mm) planar devices but little effect in 2 mm devices. No energy resolution effects were noted from moderated fission spectrum neutrons after fluences up to 1010 n/cm2, although activation was evident. CT detectors show resolution losses after fluences of 3 x 109 p/cm2 at 33 MeV for chlorine-doped detectors. Indium doped material may be more resistant. Neutron exposures (8 MeV) caused resolution losses after fluences of 2 x 1010 n/cm2. Mercuric iodide has been studied with intermediate energy protons (10 to 33 MeV) at fluences up to 1012 p/cm2 and with 1.5 GeV protons at fluences up to 1.2 x 108 p/cm2. Neutron exposures at 8 MeV have been reported at fluences up to 1015 n/cm2. No radiation damage was found under these irradiation conditions

  8. Measurement of an electron bunch shape using coherent radiation. 2

    International Nuclear Information System (INIS)

    As various studies on coherent radiation have been carried out since the first observation on coherent radiation at the Laboratory of Nuclear Science, Tohoku University in the world in 1989, the experiment on coherent radiation at the Laboratory was ceased since beginning of construction of the stretcher booster ring (STB) since 1995. In 1998, STB was finished, and a beam deflection room was maintained, where an experiment using pulse beam from Linac became possible. As in previous report, a Martin-Paplett type interferometer was made-up to carry out a trial testing using high pressure mercury lamp, here were reported on testing results of transition radiation and diffraction radiation using the beam in actual. As a result, it was found that waving of spectrum obtained in the first experiment formed by transition radiation from Al foil for vacuum shielding and the other radiation sources, so it could be solved by changing the foil position and cutting these radiation. And, on the third, it was found that mounting position of target changed spectrum, which was thought to be affected by structure of a circular board mounted by the target. (G.K.)

  9. Antenna measurement on the radiator component of an X-band Vlasov-type mode converter

    Science.gov (United States)

    Ruth, Brian G.; Schlesiger, Christian D. R.; Dahlstrom, Robert K.

    1989-07-01

    This paper addresses the radiation patterns launched from circular waveguide radiators as the first step in the design of a Vlasov-type mode converter that will function at high power levels in the X-band frquency range (8 to 12 GHz). The radiating ends of the radiators are each cut at a specific angle relative to the center axis of the waveguide to form the waveguide launcher component of a Vlasov-type mode converter. The far-field radiation patterns for three radiators were measured with an antenna pattern-mapping system.

  10. Radiation exposure in nuclear medicine: real-time measurement

    Directory of Open Access Journals (Sweden)

    Iara Sylvain

    2002-09-01

    Full Text Available French regulations have introduced the use of electronic dosimeters for personal monitoring of workers. In order to evaluate the exposure from diagnostic procedures to nuclear medicine staff, individual whole-body doses were measured daily with electronic (digital personal dosimeters during 20 consecutive weeks and correlated with the work load of each day. Personal doses remained always below 20 µSv/d under normal working conditions. Radiation exposure levels were highest to tech staff, nurses and stretcher-bearers. The extrapolated annual cumulative doses for all staff remained less than 10 % of the maximum legal limit for exposed workers (2 mSv/yr. Electronic dosimeters are not technically justified for routine survey of staff. The high sensitivity and immediate reading of electronic semiconductor dosimeters may become very useful for exposure control under risky working conditions. It may become an important help for optimising radiation protection.A legislação francesa introduziu o uso de dosímetros eletrônicos para monitoração da exposição do trabalhador. Afim de avaliar a exposição do trabalhador proveniente de exames diagnósticos em medicina nuclear, doses individuais do corpo inteiro foram medidas diariamente com dosímetros eletrônicos (digitais durante 20 semanas consecutivas e correlatas com as atividades de trabalho de cada dia. As doses foram sempre inferiores à 20 µSv por dia em condições normais de trabalho. Os níveis de exposição de radiação mais elevados foram para os enfermeiros, manipuladores e maqueiros. A extrapolação da dose anual para todos os trabalhadores foi menos que 10 % do limite máximo legal para os trabalhadores expostos (2 mSv/ano. Dosímetros eletrônicos não são tecnicamente justificados para a o controle de rotina da exposição dos trabalhadores, mas a alta sensibilidade e a leitura imediata desses dosímetros podem vir a serem muito úteis para o controle da exposição em condi

  11. Prophylactic measures of radiation injuries by natural herbs and neutraceuticals

    International Nuclear Information System (INIS)

    The application of radiation biology has gained greater relevance and significance in health and environmental issues. In the present time, nuclear terrorism and weapon related effects are raising much alarm and concern to public health. Obviously, radiation biology research has great potential in diagnosis, therapy and establishing standards for assessment risk from radiation exposure. The development of effective medical countermeasures against nuclear biological and chemical weapons is of immense importance to the defense of all nations and especially to those threatened by international terrorism. Chemical radiation protection is an important strategy to protect living being against deleterious effects of radiation. Earlier the synthetic chemical substances, which could minimize the pathological changes in the living system after exposure to ionizing radiation, were looked into. Medicinal plants are the local heritage with global importance. World is enclosed with a rich wealth of medicinal plants. Herbs have always been the principle form of medicine in India and presently they become popular. Over the last few years, interest in evaluating oriental medicinal herbs and edible phyto products for the use in anti-radiation strategies is encouraging and emerging as an acceptable approach for preventing the radiation induced lesions in many countries. Several Indian medicinal plants (Emblica officinalis, Rosemarinus officinalis, Trigonella foenum-graecum, Alstonia scholaris, Tinospora cordifolia, Phyllanthus niruri, Syzygium cumini, Aegle marmelos, Panax ginseng, Linum usitatissimum, Delonix regia etc) and antioxidant vitamins (C and E) have been tested in this laboratory by taking various biological end points for the possible use of natural products and phytochemicals to serve as radio protectors for medical countermeasures against radiation injuries, and the results obtained from such studies are highly encouraging and fruitful. It opens new avenues for the

  12. Radiation damage measurements of FET's using a radiation monitor, RadMon for LIU

    International Nuclear Information System (INIS)

    RadMon is the radiation monitor which is developed at CERN to measure the radiation dose, neutron flux and high energy particle at the same time. We are collaborating with CERN for the consolidation and upgrade of the CERN PSB RF system which may include the replacement of the present ferrite-base RF accelerating system by the new FT3L magnetic alloy cavity system. The FT3L cavities will be driven by the solid state amplifiers beside of them. To evaluate the radiation damage on the solid state amplifiers in the PSB tunnel, we measured radiation damage on the FET using the J-PARC MR beam. We located the FET's and the radiation monitor, RadMon, downstream of the collimator where the radiation level is the highest in the ring. We measured the variation of bias characteristics of the FET's during the machine operation. The accumulated dose during the experiment became higher than 12 kGy which is much higher than the expected dose in the CERN PSB tunnel. Based on the measurements, we decide the FET for the solid state amplifiers. The beam acceleration test using the amplifiers will be performed in this year. (author)

  13. Formation of diverse ring-satellite systems around Centaurs through tidal disruption at close encounters with giant planet

    CERN Document Server

    Hyodo, Ryuki; Genda, Hidenori; Ohtsuki, Keiji

    2016-01-01

    Centaurs are minor planets orbiting between Jupiter and Neptune that have or had crossing orbits with one or more giant planets. Recent observations and reinterpretation of previous observations have revealed the existence of ring systems around 10199 Chariklo and 2060 Chiron. However, the origin of the ring systems around such a minor planet is still an open question. Here, we propose that the tidal disruption of a differentiated object that experiences a close encounter with a giant planet could naturally form diverse ring-satellite systems around the Centaurs. During the close encounter, the icy mantle of the passing object is preferentially ripped off by the planet's tidal force and the debris is distributed mostly within the Roche limit of the largest remnant body. Assuming the existence of $20-50$wt% silicate core below the icy mantle, a disk of particles is formed when the objects pass within $0.4-0.8$ of the planet's Roche limit with the relative velocity at infinity $3-6$km s$^{-1}$ and 8h initial sp...

  14. Measurements of external radiation in United States dwellings

    International Nuclear Information System (INIS)

    The results of a survey of terrestrial gamma radiation levels are reported for the United States. This database represents a total of 1074 measurements in and around 247 different dwellings in several different areas of the country. The absorbed dose rate in air outdoors was found to range between 14 and 118 nGy.h-1 and averaged 46.6. nGy.h-1 , while for indoors it ranged between 12 and 160 nGy.h-1 and averaged 37.6 nGy.h-1. Apart from regional differences in the terrestrial gamma levels, variations of up to a factor of 2 can be seen in the same geographical area. Variations within a house are typically large, with basement living areas averaging 50% higher than second-floor areas. Houses of full brick construction had average indoor levels 50% higher than those for wood frame houses. The material used for interior wall construction was not found to strongly influence the indoor dose rates except for rooms containing brick, cinder block or stone. For wood frame houses, including those of brick veneer exteriors, a linear regression analysis indicates that the average indoor dose rate can be reasonably well predicted based on a constant, which relates to the building contribution, and a shielding factor for the outdoor dose rate. Using the data collected in this survey and the population weighted mean outdoor absorbed dose rate in air reported for the US, the corresponding mean indoor value is estimated to be 37 nGy.h-1. This value is in the low end of the range reported for other countries and is about half the estimated worldwide average of 70 nGy.h-1. (author)

  15. Monte Carlo analysis of radiative transport in oceanographic lidar measurements

    Energy Technology Data Exchange (ETDEWEB)

    Cupini, E.; Ferro, G. [ENEA, Divisione Fisica Applicata, Centro Ricerche Ezio Clementel, Bologna (Italy); Ferrari, N. [Bologna Univ., Bologna (Italy). Dipt. Ingegneria Energetica, Nucleare e del Controllo Ambientale

    2001-07-01

    The analysis of oceanographic lidar systems measurements is often carried out with semi-empirical methods, since there is only a rough understanding of the effects of many environmental variables. The development of techniques for interpreting the accuracy of lidar measurements is needed to evaluate the effects of various environmental situations, as well as of different experimental geometric configurations and boundary conditions. A Monte Carlo simulation model represents a tool that is particularly well suited for answering these important questions. The PREMAR-2F Monte Carlo code has been developed taking into account the main molecular and non-molecular components of the marine environment. The laser radiation interaction processes of diffusion, re-emission, refraction and absorption are treated. In particular are considered: the Rayleigh elastic scattering, produced by atoms and molecules with small dimensions with respect to the laser emission wavelength (i.e. water molecules), the Mie elastic scattering, arising from atoms or molecules with dimensions comparable to the laser wavelength (hydrosols), the Raman inelastic scattering, typical of water, the absorption of water, inorganic (sediments) and organic (phytoplankton and CDOM) hydrosols, the fluorescence re-emission of chlorophyll and yellow substances. PREMAR-2F is an extension of a code for the simulation of the radiative transport in atmospheric environments (PREMAR-2). The approach followed in PREMAR-2 was to combine conventional Monte Carlo techniques with analytical estimates of the probability of the receiver to have a contribution from photons coming back after an interaction in the field of view of the lidar fluorosensor collecting apparatus. This offers an effective mean for modelling a lidar system with realistic geometric constraints. The retrieved semianalytic Monte Carlo radiative transfer model has been developed in the frame of the Italian Research Program for Antarctica (PNRA) and it is

  16. Automated Radiation Measurements for Aviation Safety (ARMAS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The existing state-of-the-art for physics-based, data-driven, climatological specification of the global radiation environment is the capability embodied by Nowcast...

  17. Radiation temperature measurements in laser-heated hohlraums

    International Nuclear Information System (INIS)

    Two x-ray spectrographs have been used on the Trident laser at LANL to monitor the radiation temperature of small Au hohlraums. The cylindrical targets are smaller than 1 mm. The x radiation produced by ∼ 400 J of 0.53-microm laser light is detected with a 7-channel VNIIEF soft-x-ray spectrometer. Each channel employs a multi-layer mirror and a filter to limit the channel bandwidth to 1--3% of the channel energy. X rays are detected with calibrated Al x-ray diodes. A second spectrometer is based on a free-standing Au transmission grating for spectral dispersion and a multi-channel diamond photo-conductive device detector. The small hohlraum results are consistent with radiation temperatures exceeding 100 eV. Simple computer modeling shows that late in the plasma discharge, radiation of this temperature is emitted from the target

  18. Development of radiation detection and measurement system - Development of microcalorimeter for the radioactivity measurement

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Shik; Jung, H. J.; Chai, H. S.; Han, W. S. [Chungnam National University, Taejon (Korea)

    2000-03-01

    A unique multi-purpose radiation transport code has been developed and expected to be used in various fields of radiation physics and engineering. The present model is a hybrid in which the restricted energy-loss straggling is applied as in the Class I algorithm and the correlation in the secondary electron production is maintained explicitly. Output electromotive forces from the several types of the heat flux sensors have been measured as a function of the temperature differences between both end-plates of the sensors. Based on the analysis of the measurements, we could select the most appropriate type for our purpose, the sensitivity of which is greater than 45 mV/K. Heat source has also been fabricated with manganin wires and the uncertainty has been estimated to be less than 0.1%. The calorimetric core has been installed in the temporary thermal jacket surrounded by thick styrofoam and the signal from the core has been measured with power varying in the range {mu}W {approx} mW. The reproducibility has been found to be better than 0.5% for power greater than 60 {mu}W/s. In addition, it is confirmed that the heat generated by Co-60 and Ir-192 sources frequently used in industries, medicine and biology with very high level of the activity could be measured with the reproducibility better than that above mentioned. On the whole, the performance characteristics of the calorimetric core could be comparable to those commercially available. 139 refs., 40 figs., 7 tabs. (Author)

  19. Additional measurements of the radiation environment at the Los Alamos Spallation Radiation Effects Facility at LAMPF

    International Nuclear Information System (INIS)

    Foil activation dosimetry experiments were conducted in a ''rabbit'' system at the completed Los Alamos Spallation Radiation Effects Facility (LASREF). The ''raffit'' system contains four tubes spaced radially outward 0.12, 0.18, 0.27, and 0.38 meters off beam centerline. Foils were irradiated for 3 to 62 hours to measure the neutron flux and energy spectrum radially from beam centerline, along the beamline, and the effect of the Isotope Production (IP) target loadings on the neutron flux in the neutron irradiation locations. Irradiations showed a decrease in the radial flux by a factor of 6 in 0.15 meters of iron outside the IP targets. An enchancement was seen in the 24-keV energy region outside 0.15 meters. There was little difference in the shape of the spectra outside the IP targets and the beam stop with the exception of the high energy tail (energies above 20 MeV). The decrease in the high energy tail outside the beam stop is due to the degradation of the energy of the proton beam in the IP targets. Irradiations outside the beam stop with zero and eight IP targets gave the same spectral shape with the exception of the high energy tail. The magnitude of the integral flux decreased by a factor of 2 when eight IP targets were present. Irradiations with five ''rabbits'' stacked on top of each other showed no difference in the integral flux below, on and above beam centerline

  20. Development, application and marketability of radiation-utilizing measuring instruments

    International Nuclear Information System (INIS)

    The instruments equipped with radioisotopes are divided into two types. The one utilizes the ionization or the excitation of secondary radiation induced by radiation passing through substances, while the other utilizes the absorption or scattering which substances exert on radiation. Recently, the techniques of applying and manufacturing these instruments in Japan caught up with those in advanced countries in Europe and America. Thickness gauges, level gauges, gas chromatography equipments, densimeters, sulfur analyzers and moisture meters are mostly used in paper, pulp, chemical, petroleum, iron and steel, and non-ferrous metal industries. Research and educational institutes and the fields of medicine, agriculture, science and technology also utilize some of them. The instruments are applied when other appropriate method than the application of radiation cannot be found, therefore they are made one by one according to different specifications to meet severe field conditions. This situation results in high cost, and also labor- and time-consuming legal procedures and safety inspections. The users are apt to avoid the radioisotopes which are troublesome legally and socially. Also various sealed radiation sources rely mostly on imports. Notwithstanding these problems, the economical effectiveness of the radiation-utilizing instruments is very large. The basic research and the development of combined application techniques must be forwarded. (Kako, I.)

  1. Surfactant release as an early measure of radiation pneumonitis

    International Nuclear Information System (INIS)

    The immediate release of surfactant into lung alveoli following irradiation has been studied as a potential indicator for the later development of radiation pneumonitis. Utilizing single dose radiation exposure to the whole thorax in male LAF1/J mice, steep dose response curves for lavaged alveolar surfactant were identified at 7 and 28 days after exposure. Seven days after irradiation there was no elevation with doses up to and including 12 Gy; above this dose a detectable increase occurred. At 28 days the surfactant recovered by lavage was elevated compared to the levels seen at day 7 for all doses; doses > 12 Gy produced surfactant values significantly greater than those found in mice treated with 12 Gy or less. The radiation pulmonary lethality dose response curve assessed four months later indicated an LD50 value of approx. 13 Gy. The early biochemical effect and the later radiation pneumonitis lethalities therefore closely coincided. The evidence strongly indicates that alveolar surfactant release uncovered hours to days after radiation exposure may be an early biochemical marker that predicts for subsequent pneumonitis radiation injury

  2. Radiation Protection in Educational Institutions. Recommendations of the National Council on Radiation Protection and Measurements.

    Science.gov (United States)

    National Council on Radiation Protection and Measurements, Washington, DC.

    The problems involved when radiation-producing devices of our contemporary technology are used in the teaching of science at the high school and undergraduate college level are discussed. Information is provided on the hazards involved in the use of radiation-producing equipment or radioactive materials in science demonstrations and experiments…

  3. Support activities for radiation protection and measurements in Kawamata-machi, Fukushima prefecture, Japan

    International Nuclear Information System (INIS)

    Kinki University Atomic Energy Research Institute has supported Kawamata-machi, Fukushima prefecture, Japan since the Fukushima Daiichi Nuclear Power Plant accident. The support activity includes the measurement of environmental radiation in the area, radioactivity measurement of botanical samples and soil, individual dosimetry for children and radiation education for residents. (author)

  4. Radiation dose measurements during kilovoltage-cone beam computed tomography imaging in radiotherapy

    Directory of Open Access Journals (Sweden)

    A Sathish Kumar

    2016-01-01

    Conclusion: Radiation dose to the eye, breast, and the surface of the pelvis have been arrived at during CBCT. The doses measured on patients agreed closely with those measured on humanoid phantom and with published values.

  5. Radiation

    International Nuclear Information System (INIS)

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  6. Measurement and modelling of radiation transmission within a stand of maritime pine (Pinus pinaster Ait)

    International Nuclear Information System (INIS)

    A semi-empirical model of radiation penetration in a maritime pine canopy was developed so that mean solar (and net) radiation absorption by crowns and understorey could be estimated from above-canopy measurements only. Beam radiation Rb was assumed to penetrate the canopy according to Beer's law with an extinction coefficient of 0.32; this figure was found using non-linear regression techniques. For diffuse sky radiation, Beer's law was integrated over the sky vault assuming a SOC (standard overcast sky) luminance model; the upward and downward scattered radiative fluxes were obtained using the Kubelka-Munk equations and measurements of needle transmittance and reflectance. The penetration of net radiation within the canopy was also modelled. The model predicts the measured albedo of the stand very well. The estimation of solar radiation transmitted by the canopy was also satisfactory with the maximum difference between this and the mean output of mobile sensors at ground level being only 18 W m-2. Due to the poor precision of net radiometers, the net radiation model could not be tested critically. However, as the modelled longwave radiation balance under the canopy is always between -10 and -20 Wm-2, the below-canopy net radiation must be very close to the solar radiation balance. (author)

  7. The direct measurement using an imaging plate for coincidence of radiation centre and laser position in external radiation therapy

    International Nuclear Information System (INIS)

    A new method of quality assurance has been studied to measure coincidence of the radiation centre and a patient-setup laser position on a transverse plane to the beam at the isocentre. This measurement is achieved by using an imaging plate (IP). When radiation is applied to an IP, the energy is stored as trapped electrons. The number of electrons is decreased by local laser exposure. As a result, the radiation field produced by external beam irradiation is recorded as 'positive' information and the position of the patient-setup laser is recorded as 'negative' on an IP. The advantages of this method are the direct measurement, short time and high resolution. These are required for daily and monthly quality checks. We confirmed the advantage of this method by an experiment using a proton beam. (note)

  8. Lessons learned from the Radiation measurements of the Mars Science Lab Radiation Assessment Detector (MSL-RAD)

    Science.gov (United States)

    Reitz, Guenther; Ottolenghi, Andrea

    2016-07-01

    The Radiation Assessment Detector (RAD) was designed to characterize the radiation environment on the Mars surface and to contribute to an improved assessment of radiation risk for a future human mission to Mars. The flight was chosen to cover a period of solar maximum activity to allow besides the measurement of the galactic cosmic rays an intense study of exposures by solar particle events. The Mars Science Laboratory spacecraft (MSL), containing the Curiosity rover, in which RAD was integrated, was launched to Mars on November 26, 2011. Although not part of the mission planning, RAD was operated already during the 253 day and 560 million km cruise to Mars and made the first time detailed measurements of a radiation environment comparable to that inside a future spacecraft carrying humans to Mars and in other deep space missions. Exactly 100 years after the discovery of cosmic rays on August 7, 1912 RAD makes the first observation of the radiation environment on the surface of another planet and is still gathering data until today. Meanwhile the maximum activity of the current solar cycle has been passed and the solar activity is decreasing. Unfortunately the present solar cycle was an unexpected weak cycle. As a matter of fact only very small solar particle events could be observed during the still ongoing RAD measurements. The paper highlights the achievements of RAD by presenting selected data measured during the cruise and on the Mars surface and describes its impact on predictive models for health risks of astronauts during space missions.

  9. A study on the real-time radiation dosimetry measurement system based on optically stimulated luminescence

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-Ping; CHEN Zhao-Yang; BA Wei-Zhen; FAN Yan-Wei; DU Yan-Zhao; PAN Shi-Lie; GUO Qi

    2008-01-01

    The optically stimulated luminescent (OSL) radiation dosimeter technically surveys a wide dynamic measurement range and a high sensitivity.Optical fiber dosimeters provide capability for remote monitoring of the radiation in the locations which are difficult-to-acoess and hazardous.In addition.optical fiber dosimeters are immune to electrical and radio-frequency interference.In this paper,a novel remote optical fiber radiation dosimeter is described.The optical fiber dosimeter takes advantage of the charge trapping materials CaS:Ce, Sm that exhibit OSL.The measuring range of the dosimeter is from 0.1 to 100 Gy.The equipment is relatively simple and small in size,and has low power consumption.This device is suitable for measuring the space radiation dose and also can be used in high radiation dose condition and other dangerous radiation occasions.

  10. National Council on Radiation Protection and Measurements semiannual technical progress report, March 1989--August 1989

    International Nuclear Information System (INIS)

    This semiannual technical progress report is for the period 1 March 1989 through 31 August 1989. This National Council on Radiation Protection and Measurements (NCRP) program is designed to provide recommendations for radiation protection based on scientific principles. During this period several reports were published covering the topics of occupational radiation exposure, medical exposure, radon control, dosimetry, and radiation protection standards. Accomplishments of various committees are also reported; including the committees on dental x-ray protection, radiation safety in uranium mining and milling, ALARA, instrumentation, records maintenance, occupational exposures of medical personnel, emergency planning, and others. (SM)

  11. Radiation environment measurements on shuttle missions using the CREAM experiment

    Science.gov (United States)

    Dyer, C. S.; Sims, A. J.; Truscott, P. R.; Farren, J.; Underwood, C.

    1992-12-01

    The Cosmic Radiation Environment and Activation Monitor (CREAM) was successfully deployed in the middeck area on Shuttle missions STS-48 and STS-44 during September and November 1991 with the aim of monitoring those aspects of the primary and secondary radiation environment responsible for single event upsets in microelectronics and background noise in sensors. Results are compared with the outputs of standard radiation environment models. For the accurate location of trapped protons the choice of geomagnetic field model is shown to be critical, while results at high latitudes show the low-altitude manifestation of the new trapped proton belt observed to follow the March 1991 solar flare event. From deployment at a number of locations there is clear evidence for a significant build-up with shielding of secondary charged particles and neutrons.

  12. Local radiation protection measurement network for TRIGA Reactor building

    International Nuclear Information System (INIS)

    This system is intended for the protection of personal working in those areas of the reactor building where high gamma radiation fields are expected. A detector, sensitive to gamma radiation, is installed in each of the areas to be monitored. The detector will send a signal proportional to the radiation level in the area, to a corresponding electronic module (Alarm Unit), where the signal will be amplified and checked against alarm set-points for possible alarming condition. In case the field exceeds the alarm set-point, the Alarm Unit will produce a signal that will trigger the field alarms (Horn and Beacon), located in the area where that condition occurred. Each Alarm Unit will send a numerical input to central computer command. (authors)

  13. Shielding of Medical Radiation Facilities - National Council on Radiation Protection and Measurements Reports No. 147 and No. 151

    International Nuclear Information System (INIS)

    The National Council on Radiation Protection and Measurements of the United States (NCRP) has issued two reports in the past 18 months that provide methods and data for designing shielding for diagnostic radiological imaging and radiation therapy facilities. These reports update previous publications on this subject with revised methods that take into account new technologies, results from measurements and new data that have been published in the last 30 years. This paper gives a brief summary of the contents of these reports, the methods recommended for determining the shielding required and the data provided to aid in the calculations

  14. Atmospheric Radiation Measurement program climate research facility operations quarterly report.

    Energy Technology Data Exchange (ETDEWEB)

    Sisterson, D. L.; Decision and Information Sciences

    2006-09-06

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1-(ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,965.60 hours (0.90 x 2,184), and that for the Tropical Western Pacific (TWP) locale is 1,856.40 hours (0.85 x 2,184). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,074.80 hours (0.95 x 2,184). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive

  15. Measurements of dose equivalent of mixed radiation outside the Serpukhov proton synchrotron shield

    CERN Document Server

    Antipov, A V; Golovachik, V T; Khefert, M; Krupnyi, G I; Kustarev, V N; Lebedev, V N

    1979-01-01

    Comparative measurements of radiation doses outside the Serpukhov proton synchrotron shield were made with the component method (CM) and the 'Cerberus' instrument used at the Institute of High Energy Physics (IHEP) and CERN as radiation monitors, and also with the 'Sukhona-2' recombination dosimeter, a linear energy transfer radiation spectrometer based on a tissue equivalent (TE) proportional counter and a TE ionization chamber, employed at the IHEP for the direct measurements of doses and for calibrating monitoring devices used in radiation fields having an unknown composition and spectrum. (23 refs) .

  16. An information theory approach for evaluating earth radiation budget (ERB) measurements - Nonuniform sampling of reflected shortwave radiation

    Science.gov (United States)

    Barkstrom, Bruce R.; Direskeneli, Haldun; Halyo, Nesim

    1992-01-01

    An information theory approach to examine the temporal nonuniform sampling characteristics of shortwave (SW) flux for earth radiation budget (ERB) measurements is suggested. The information gain is computed by computing the information content before and after the measurements. A stochastic diurnal model for the SW flux is developed, and measurements for different orbital parameters are examined. The methodology is applied to specific NASA Polar platform and Tropical Rainfall Measuring Mission (TRMM) orbital parameters. The information theory approach, coupled with the developed SW diurnal model, is found to be promising for measurements involving nonuniform orbital sampling characteristics.

  17. A study on the radiation and environmental safety -Development of radiation protection and measurement technology-

    Energy Technology Data Exchange (ETDEWEB)

    Jang, See Yung; Lee, Tae Yung; Lee, Hyung Sub; Kim, Jan Ryul; Kim, Chang Kyung; Kim, Bong Hwan; Yoon, Kyung Soo; Jung, Kyung Kee; Jung, Duk Yun; Lee, Bong Jae; Yoon Suk Chul; Lee, Kee Chang; Yoon, Yu Chang; Jung, Rae Ik; Lee, Sang Yoon; Han, Yung Dae; Kim, Jong Soo, I; Kim, Jong Soo, II; Suh, Kyung Won [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kim, Jong Kyung [Han Yang Univ., Seoul (Korea, Republic of)

    1995-07-01

    Reference X- and neutron radiation fields have been established and evaluated to support the national radiation protection programme under which performance evaluation test for domestic personal dosimetry will be implemented by the ministerial ordinance 1992-15, and to provide a basic technical support in radiation protection dosimetry. Personal dose evaluation algorithm has been developed with the KAERI reference radiation fields which comply well with those in the new ANSI N13.11(1993) to evaluate accurate personal dose equivalents. A personal internal dosimetry algorithm which can estimate the intakes of radionuclides from the results of whole body direct bioassay and the resulting internal doses has been also developed and evaluated to be equally excellent compared with those being used in foreign countries. A BOMAB phantom for precise WBC calibration has also designed, fabricated and test-evaluated. A principal method for estimating the cost for radiation protection which is important in performing a cost-benefit analysis for the radiation protection optimization study based on the ALARA principle has been preliminarily investigated and suggested. 49 figs, 67 tabs, 50 refs. (Author).

  18. A study on the radiation and environmental safety -Development of radiation protection and measurement technology-

    International Nuclear Information System (INIS)

    Reference X- and neutron radiation fields have been established and evaluated to support the national radiation protection programme under which performance evaluation test for domestic personal dosimetry will be implemented by the ministerial ordinance 1992-15, and to provide a basic technical support in radiation protection dosimetry. Personal dose evaluation algorithm has been developed with the KAERI reference radiation fields which comply well with those in the new ANSI N13.11(1993) to evaluate accurate personal dose equivalents. A personal internal dosimetry algorithm which can estimate the intakes of radionuclides from the results of whole body direct bioassay and the resulting internal doses has been also developed and evaluated to be equally excellent compared with those being used in foreign countries. A BOMAB phantom for precise WBC calibration has also designed, fabricated and test-evaluated. A principal method for estimating the cost for radiation protection which is important in performing a cost-benefit analysis for the radiation protection optimization study based on the ALARA principle has been preliminarily investigated and suggested. 49 figs, 67 tabs, 50 refs. (Author)

  19. Evaluation of Diversity Antenna Designs Using Ray Tracing, Measured Radiation Patterns, and MIMO Channel Measurements

    Directory of Open Access Journals (Sweden)

    Pal Arindam

    2007-01-01

    Full Text Available This paper presents an evaluation of the MIMO performance of three candidate antenna array designs, each embedded within a PDA footprint, using indoor wideband channel measurements at 5.2 GHz alongside channel simulations. A channel model which employs the plane-wave approximation was used to combine the embedded antenna radiation patterns of the candidate devices obtained from far-field pattern measurements and multipath component parameters from an indoor ray-tracer. The 4-element candidate arrays were each constructed using a different type of antenna element, and despite the diverse element directivities, pattern characteristics, and polarization purities, all three devices were constructed to fully exploit diversity in polarization, space, and angle. Thus, low correlation and high information theoretic capacity was observed in each case. A good match between the model and the measurements is also demonstrated, especially for MIMO subsets of identically or orthogonally polarized linear slot antennas. The interdependencies between the channel XPD, directional spread and pathloss, and the respective impact on channel capacity are also discussed in this paper.

  20. Evaluation of Diversity Antenna Designs Using Ray Tracing, Measured Radiation Patterns, and MIMO Channel Measurements

    Directory of Open Access Journals (Sweden)

    Arindam Pal

    2007-01-01

    Full Text Available This paper presents an evaluation of the MIMO performance of three candidate antenna array designs, each embedded within a PDA footprint, using indoor wideband channel measurements at 5.2 GHz alongside channel simulations. A channel model which employs the plane-wave approximation was used to combine the embedded antenna radiation patterns of the candidate devices obtained from far-field pattern measurements and multipath component parameters from an indoor ray-tracer. The 4-element candidate arrays were each constructed using a different type of antenna element, and despite the diverse element directivities, pattern characteristics, and polarization purities, all three devices were constructed to fully exploit diversity in polarization, space, and angle. Thus, low correlation and high information theoretic capacity was observed in each case. A good match between the model and the measurements is also demonstrated, especially for 2×2 MIMO subsets of identically or orthogonally polarized linear slot antennas. The interdependencies between the channel XPD, directional spread and pathloss, and the respective impact on channel capacity are also discussed in this paper.

  1. DOSIMETRY MEASUREMENTS WITH TIMEPIX IN MIXED RADIATION FIELDS

    Czech Academy of Sciences Publication Activity Database

    Ploc, Ondřej; Uchihori, Y.; Molokanov, A. V.; Pinsky, L.

    Vol. 34. Bratislava : SMU - Faculty of Public Health, 2014. s. 119-119. ISBN 978-80-89384-08-2. [XXXVI.Dny radiační ochrany. 10.11.2014-14.11.2014, Poprad] Institutional support: RVO:61389005 Keywords : radiation fields * Timepix * LET spectra Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

  2. Measurement and Modeling of Particle Radiation in Coal Flames

    DEFF Research Database (Denmark)

    Bäckström, Daniel; Johansson, Robert; Andersson, Klas Jerker;

    2014-01-01

    This work aims at developing a methodology that can provide information of in-flame particle radiation in industrial-scale flames. The method is based on a combination of experimental and modeling work. The experiments have been performed in the high-temperature zone of a 77 kWth swirling lignite...

  3. Measures of lifetime detriment from radiation exposures: Principles and methods

    International Nuclear Information System (INIS)

    This report presents the work initiated at the 'Workshop on the comparison of methods for deriving life long risk indices for the effects of ionizing radiations', organized by CEPN in Fontenay-aux-Roses (France), on August 7-11, 1989. It has been written in collaboration by participants during the following years

  4. 47 CFR 2.1511 - Measurements of radiated emissions.

    Science.gov (United States)

    2010-10-01

    ... quarter-wave monopole antenna located on a one wavelength minimum diameter metal ground plane. The Rules... internal battery with its standard antenna attached and deployed. (b) Set-up for radiated EME tests. Step (1) Place a 121.5 MHz quarter-wave vertical antenna element at the center of the ground plane...

  5. Instruments for radiation measurement in biosciences. Series 3. radioluminography. 13. Application of imaging plate for radiation control works

    International Nuclear Information System (INIS)

    The imaging plate (IP) is useful for measurement of both distribution and intensity of radiation. This paper described application of IP in radiation control works. Since IP has the 500 times higher sensitivity than the film badge for X-ray-range radiation of 12-120 keV, it can be useful as a personnel dosemeter in medical field. IP is suitable for measurement of radioactivity in a lot of samples and it can be useful for measurement of smear test papers although a problem concerning 3H monitoring remains. Since IP gives the two-dimensional information of radiation distribution, IP can be useful for monitoring of contamination status such as its site and area. A contamination accident occurred by 68Ge in PET apparatus is described for instance. IP can be also useful for measurement of the low level radioactivity in solutions, such as waste water. The author made an apparatus for drain monitoring which composed from acryl-box and IP. The surface of the former box, containing the water, is stuck by various shields of acryl- and lead-plates and is in contact with IP. Both measurement of radioactivity concentration and identification of radionuclide are possible. The important defect is pointed out to be fading phenomenon in those works above. (K.H.)

  6. The use of microcontrollers in the radiation measurements and related works in TAEA laboratories

    International Nuclear Information System (INIS)

    Full text: In recent years, the micro-controllers are used intensively in the measurements of radiation. The use of micro-controllers make possible many functions to be incorporated in instruments with reduced dimensions and cost. In this report the related works carried by Nuclear Electronics Department, Cekmece Nuclear Research and Training Center, TAEA are presented. Among the different type of radiation measuring instruments the last developed 'NEB.223 Radiacmeter' is an excellent multi-purpose portable radiation meter having wide measuring range and multi-functions. The 'Early Warning Environmental Radiation Monitoring System On-Line (RESA)' consists of the remote stations to measure the radiation level and the data and of an information center running the server software on a personnel computer. The Center communicates with the remote stations through telephone lines

  7. Radiation

    International Nuclear Information System (INIS)

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  8. Mineral Dust Impact on Short- and Long-Wave Radiation and Comparison with Ceres Measurements

    Science.gov (United States)

    Romano, Salvatore; Perrone, Maria Rita

    2016-06-01

    Clear-sky downward and upward radiative flux measurements both in the short- and in the long-wave spectral range have been used to estimate and analyze the radiation changes at the surface due to the mineral dust advection at a Central Mediterranean site. Then, short- and long-wave radiative fluxes retrieved from the CERES (Clouds and the Earth's Radiant Energy System) radiometer sensors operating on board the EOS (Earth Observing System) AQUA and TERRA platforms have been used to evaluate the mineral dust radiative impact at the top of the atmosphere. Satellite-derived radiative fluxes at the surface have been compared with corresponding ground-based flux measurements, collocated in space and time, to better support and understand the desert dust radiative impact. Results referring to the year 2012 are reported.

  9. On measurements and modeling of ultraviolet radiation with focus on the Antarctic

    OpenAIRE

    Meinander, Outi

    2007-01-01

    The aim of the work was to study, on the basis of literature and experiments, the aspects of measuring and modeling ultraviolet radiation. For measurements, both the spectral and the non-spectral approaches were included. For modeling, physical and statistical models were applied. Thereafter the satellite UV estimates, i.e. spaceborn spectrometer measurements on solar radiation combined with physical UV modeling, were shortly introduced. Case studies were carried out for each of the five case...

  10. Atmospheric Radiation Measurement program (ARM) -- Summer 1995 review

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, G.; Ruderman, M.; Treiman, S.

    1995-10-01

    ARM is a highly focused program designed to improve the understanding of the transport of infrared and solar radiation through the atmosphere. The program pays particular attention to the interaction of radiation with the three phases of water. The goals of ARM are usually articulated in terms of improvements in climate models. The authors agree that ARM can indeed make significant contributions to the understanding of climate change. In addition the authors believe that the results of the program will have wide applicability to a broad range of problems, including more accurate short-term and seasonal weather forecasting. This report examines the issues of anomalous atmospheric absorption and makes recommendations concerning future directions for the ARM program.

  11. Measurement of ionizing radiations for the orthodontics diagnosis

    International Nuclear Information System (INIS)

    The amount of radiation which is subjected a child during the taking of x-rays of routine for the orthodontics diagnosis is analyzed. The study was made to 26 children (men and women) between 7 and 13 years of age with healthy teething. During the taking of different radiographs a thermoluminescent crystal of lithium fluoride was positioned beforehand in the place of entrance of the ray. Itself proceeded to read the crystals in the Laboratorio de Fisica Nuclear de la Universidad de Costa Rica. Later the comparisons with the standards already established at worldwide level were made. As main conclusions obtained are that taboo in existence at present on x-rays do not include ionizing radiations for the orthodontics use and that the anterior-posterior radiographs are those that release more photons followed of the cephalometric radiography. (author)

  12. A Method for Ultrashort Electron Pulse Shape-Measurement Using Coherent Synchrotron Radiation

    OpenAIRE

    Geloni, G. A.; Saldin, E. L.; Schneidmiller, E. A.; Yurkov, M. V.

    2003-01-01

    In this paper we discuss a method for nondestructive measurements of the longitudinal profile of sub-picosecond electron bunches for X-Ray Free Electron Lasers (XFELs). The method is based on the detection of the Coherent Synchrotron Radiation (CSR) spectrum produced by a bunch passing a dipole magnet system. This work also contains a systematic treatment of synchrotron radiation theory which lies at the basis of CSR. Standard theory of synchrotron radiation uses several approximations whose ...

  13. Channeling-radiation measurements at Lawrence Livermore National Laboratory

    International Nuclear Information System (INIS)

    In the last few years, the amount and quality of channeling-radiation data have increased enormously, owing largely to much improved experimental capabilities. Current results include improved interplanar potentials for diamond, the description of the effect of platelets in diamond as an average thermal vibration, an improved determination of the Debye temperature of silicon, an improved determination of the thermal-vibration amplitude of LiD, and the demonstration that LiF crystal structures can survive intense electron bombardment

  14. Demonstration of reduced radiation losses in hohlraums made from cocktail mixtures by measuring increased radiation temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Jones, O; Schein, J; Rosen, M; Suter, L; Wallace, R; Dewald, E; Glenzer, S; Campbell, K; Gunther, J; Hammel, B; Landen, O; Sores, C; Olson, R; Rochau, G; Wilkens, H; Kaae, J; Kilkenny, J; Nikroo, A; Regan, S; Meyerhoffer, D

    2006-11-03

    We present results from experiments, numerical simulations, and analytic modeling that demonstrate enhanced radiation confinement of hohlraums made from cocktail materials. We summarize the results from several previous planar sample experiments that showed the potential promise of cocktails. We then discuss a series of more recent hohlraum experiments that attempted to demonstrate enhanced radiation confinement. Once we understood the importance of oxygen contamination in increasing the specific heat and wall losses of uranium-based cocktails, we implemented new manufacturing and handling techniques for cocktail hohlraums that led to our demonstration of a significant increase in radiation temperature (up to +7eV at 300 eV) compared to a pure Au hohlraum. This data agrees well with modeling and suggests we can expect an 18% reduction in wall loss (and 10% reduction in laser energy) for the current ignition design by switching to cocktail hohlraums.

  15. Dose equivalent measurements in mixed and time varying radiation fields around high-energy accelerators

    CERN Document Server

    Mayer, S

    2003-01-01

    Measurements of ambient dose equivalent in stray radiation fields behind the shielding of high-energy accelerators are a challenging task. Several radiation components (photons, neutrons, charged particles, muons, etc.), spanning a wide range of energies, contribute to the total dose equivalent. The radiation fields are produced by beam losses interacting with structural material during the acceleration or at the ejection to experimental areas or other accelerators. The particle beam is usually not continuous but separated in "bunches" or pulses, which further complicates dose measurements at high-energy accelerators. An ideal dosimeter for operational radiation protection should measure dose equivalent for any composition of radiation components in the entire energy range even when the field is strongly pulsed. The objective of this work was to find out if an ionisation chamber operated as a "recombination chamber" and a TEPC instrument using the variance-covariance method ("Sievert Instrument") are capable ...

  16. Influence of Participating Media on the Radiation Thermometry for Surface Temperature Measurement

    Institute of Scientific and Technical Information of China (English)

    Yuying LIU; Xinxin ZHANG

    2005-01-01

    A temperature measurement model of radiation thermometry for the surface covered by participating media was developed. The model was based on the radiation heat transfer of participating media and principles of radiation pyrometers, and solved by integral formulation of discrete ordinate method on spectral waveband. The influence of water mist on the indicated temperature of Raytek MR1SB one/two color pyrometer was discussed. Mie theory was used to calculate the radiative properties of water mist. In order to verify the model, a laboratory temperature measurement experiment was executed. The result shows that temperature of radiation thermometry is sensitive to the spectral response wavelength of pyrometer, and the simulated temperature of pyrometer agrees well with the experimental measurements on a suitable wavelength. The simulated temperature was lower than the real temperature of surface for one-color pyrometer, and it could be higher or lower than the real one for two-color pyrometer with the influence of participating media.

  17. Detector Response and Beam Line Transmission Measurements with Far-Infrared Radiation

    CERN Document Server

    Grimm, O; Fröhlich, L

    2005-01-01

    Various activities at the TTF linear accelerator at DESY, Hamburg, that drives the VUV-FEL are geared towards measuring the longitudinal charge distribution of electron bunches with coherent far-infrared radiation. Examples are beam lines transporting synchrotron or transition radiation to interferometers mounted inside or outside the tunnel, and studies of single-shot grating spectrometers. All such approaches require a good understanding of the radiation generation and transport mechanism and of the detector characteristics to extract useful information on the charge distribution. Simulations and measurements of the expected transverse intensity distribution and polarization of synchrotron radiation emitted at the first bunch compressor of TTF have been performed. The transverse intensity scanning provided for the first time at DESY a visual image of the footprint of terahertz radiation. Detector response measurements have been performed at the FELIX facility, Netherlands, for wavelengths between 100-160 mi...

  18. Radioactivity measurement of radioactive contaminated soil by using a fiber-optic radiation sensor

    Science.gov (United States)

    Joo, Hanyoung; Kim, Rinah; Moon, Joo Hyun

    2016-06-01

    A fiber-optic radiation sensor (FORS) was developed to measure the gamma radiation from radioactive contaminated soil. The FORS was fabricated using an inorganic scintillator (Lu,Y)2SiO5:Ce (LYSO:Ce), a mixture of epoxy resin and hardener, aluminum foil, and a plastic optical fiber. Before its real application, the FORS was tested to determine if it performed adequately. The test result showed that the measurements by the FORS adequately followed the theoretically estimated values. Then, the FORS was applied to measure the gamma radiation from radioactive contaminated soil. For comparison, a commercial radiation detector was also applied to measure the same soil samples. The measurement data were analyzed by using a statistical parameter, the critical level to determine if net radioactivity statistically different from background was present in the soil sample. The analysis showed that the soil sample had radioactivity distinguishable from background.

  19. Radiation protection measures to support the life of population at contaminated territories

    International Nuclear Information System (INIS)

    At the contaminated territories from the first days after the accident at Chernobyl NPP protection measures are conducted with the aim to decrease the total dose of radiation to a limited level and to decrease the risk of cancer deceases and genetic consequences for living and next generations. Radiation protection measures at these territories are the following: radiation control of food and environment; measures on lowering the content of radionuclides in the air, water and soils; measures to supply people with clean food and products of agriculture; lowering the dose loading during X-ray diagnostics; control of radon influence, resettlement of population to the clear territories. Apart from that measures on development of medical service, supply with fool-bodied food, lowering the sociopsychological tension, education in the field of radiation protection and legal knowledge are conducted. The results of activity are shown

  20. Induction method of pulse gamma-radiation exposure dose rate measurement

    Energy Technology Data Exchange (ETDEWEB)

    Buber, V.B.; Stepanov, V.M.

    1984-01-01

    Induction method of measurement of pulse ..gamma..-radiation exposure dose rate is presented. The measurements are made by charge detectors of induction type. The ..gamma..-radiation dose rate is given versus the Compton current excited by irradiation. The induction method permits to measure the pulse ..gamma..-radiation exposure dose rate up to the values of 10/sup 7/ A/kg with the time resolution of 10/sup -8/ s and with the error not exceeding 20%. The method is slightly subjected to the effect of external conditions, it permits to measure the local and integral radiation characteristics; its application results in quite insignificant distortions of the ..gamma..-flux being measured.

  1. Comparison of Martian Surface Radiation Predictions to the Measurements of Mars Science Laboratory Radiation Assessment Detector (MSL/RAD)

    Science.gov (United States)

    Kim, Myung-Hee Y.; Cucinotta, Francis A.; Zeitlin, Cary; Hassler, Donald M.; Ehresmann, Bent; Rafkin, Scot C. R.; Wimmer-Schweingruber, Robert F; Boettcher, Stephan; Boehm, Eckart; Guo, Jingnan; Koehler, Jan; Martin, Cesar; Reitz, Guenther; Posner, Erik

    2014-01-01

    For the analysis of radiation risks to astronauts and planning exploratory space missions, detailed knowledge of particle spectra is an important factor. Detailed measurements of the energetic particle radiation environment on the surface of Mars have been made by the Mars Science Laboratory Radiation Assessment Detector (MSL-RAD) on the Curiosity rover since August 2012, and particle fluxes for a wide range of ion species (up to several hundred MeV/u) and high energy neutrons (8 - 1000 MeV) have been available for the first 200 sols. Although the data obtained on the surface of Mars for 200 sols are limited in the narrow energy spectra, the simulation results using the Badhwar-O'Neill galactic cosmic ray (GCR) environment model and the high-charge and energy transport (HZETRN) code are compared to the data. For the nuclear interactions of primary GCR through Mars atmosphere and Curiosity rover, the quantum multiple scattering theory of nuclear fragmentation (QMSFRG) is used, which includes direct knockout, evaporation and nuclear coalescence. Daily atmospheric pressure measurements at Gale Crater by the MSL Rover Environmental Monitoring Station are implemented into transport calculations for describing the daily column depth of atmosphere. Particles impinging on top of the Martian atmosphere reach the RAD after traversing varying depths of atmosphere that depend on the slant angles, and the model accounts for shielding of the RAD by the rest of the instrument. Calculations of stopping particle spectra are in good agreement with the RAD measurements for the first 200 sols by accounting changing heliospheric conditions and atmospheric pressure. Detailed comparisons between model predictions and spectral data of various particle types provide the validation of radiation transport models, and thus increase the accuracy of the predictions of future radiation environments on Mars. These contributions lend support to the understanding of radiation health risks to

  2. Measurement of the 2-dimensional plasma radiation structure during asymmetric radiative collapse by a tangentially viewing infrared imaging video bolometer on LHD

    International Nuclear Information System (INIS)

    The infrared (IR) imaging video bolometer (IRVB) is a new type of plasma radiation measurement system, which uses an IR camera. For the 4th LHD campaign (2000), the IRVB type has been installed at a tangential port. Very clear helical plasma radiation structures were measured which agreed well with corresponding images of CIII radiation from a CCD camera. A change in the two-dimensional spatial distribution of the radiated power is observed during radiative collapse of the plasma which indicates that the asymmetric radiation is coming from the lower inboard side. (author)

  3. Characteristics and Measurement of Radioactivity and Radiation Levels. Annex I of Technical Volume 4

    International Nuclear Information System (INIS)

    This annex provides background information on the quantities and units used in radiation protection and an introduction to the characteristics of radioactive material. Discussed are also their dispersion and deposition in the terrestrial environment and their measurement as well as the assessment of the resulting exposure due to ionizing radiation emitted by radioactive material

  4. Methods of measurements on incidental X-radiation from electron tubes

    International Nuclear Information System (INIS)

    The standard describes the method for detection of x-radiation and the method for the direct and indirect measurement of field pattern and exposure rate of random incidental radiation emanating from high voltage electron tubes. Required apparatus and calibration procedure for the exposure rate meter or film mount are described. (M.G.B.)

  5. Spectrum of the cosmic background radiation: early and recent measurements from the White Mountain Research Station

    International Nuclear Information System (INIS)

    The White Mountain Research Station has provided a support facility at a high, dry, radio-quiet site for measurements that have established the blackbody character of the cosmic microwave background radiation. This finding has confirmed the interpretation of the radiation as a relic of the primeval fireball and helped to establish the hot Big Bang theory as the standard cosmological model

  6. BOBMEX-98 Pilot: Measurement and analysis of incoming shortwave radiation data

    Indian Academy of Sciences (India)

    K Gopala Reddy; P Sree Ram

    2000-06-01

    Empirical formulae for estimation of hourly incoming shortwave radiation over the Indian Ocean under different cloud amounts have been developed by using the pyranometer measurements of the incoming solar radiation and the cloud observations during BOBMEX Pilot (October - November 1998) cruise.

  7. Regulations concerning protective measures against radiation in case of accidents connected with gamma radiography

    International Nuclear Information System (INIS)

    Pursuant to the 1938 Act on X-rays and radium, etc and the 1976 regulations on supervision and use of installations and apparatus which release radiation representing a hazard to health, the State Institute of Radiation Health issued these regulations laying down a series of protective measures in case of accidents when using gamma radiography. They entered into force on 1 July 1981

  8. Development of Precision Information Measuring System for Ultraviolet Radiation

    Directory of Open Access Journals (Sweden)

    ROSHCHUPKIN, O.

    2014-08-01

    Full Text Available Results of studying the neural network method are presented to reduce the amount of calibration points for the multisensor (MS, in particular for the photodiode. This allows transmitting to the MS individual conversion function and provides the high accuracy of measurement. The structure of synthesized information-measuring system and its measuring channel has created for implementing of the proposed approach. A structural scheme is proposed as well for values transmitting the etalon measures to measuring systems. Its used to determine the errors of photodiodes, as those which are produced for customers. This assures the interchangeability of sensors when using the individual conversion function.

  9. Atmospheric Radiation Measurement Program facilities newsletter, February 2001.; TOPICAL

    International Nuclear Information System (INIS)

    This newsletter consists of the following: (1) ARM Science Team Meeting Scheduled-The 11th Annual ARM Science Team meeting is scheduled for March 19-23, 2001, in Atlanta, Georgia. Members of the science team will exchange research results achieved by using ARM data. The science team is composed of working groups that investigate four topics: instantaneous radiative flux, cloud parameterizations and modeling, cloud properties, and aerosols. The annual meeting brings together the science team's 150 members to discuss issues related to ARM and its research. The members represent universities, government laboratories and research facilities, and independent research companies. (2) Communications to Extended Facilities Upgraded-New communications equipment has been installed at all of the SGP extended facilities. Shelters were installed to house the new equipment used to transfer data from instruments via the Internet to the site data system at the central facility. This upgrade has improved data availability from the extended facilities to 100% and reduced telephone costs greatly. (3) SGP Goes ''Buggy''-Steve Sekelsky, a researcher from the University of Massachusetts, is planning to bring a 95-GHz radar to the SGP central facility for deployment in March-October 2001. The radar will help to identify signals due to insects flying in the air. The ARM millimeter cloud radar, which operates at 35 GHz, is sensitive to such insect interference. Testing will also be performed by using a second 35-GHz radar with a polarized radar beam, which can differentiate signals from insects versus cloud droplets. (4) Winter Fog-Fog can add to hazards already associated with winter weather. Common types of fog formation include advection, radiation, and steam. Advection fog: An advection fog is a dense fog that forms when a warm, moist air mass moves into an area with cooler ground below. For example, fog can form in winter when warmer, water-saturated air from the south (associated with

  10. Atmospheric Radiation Measurement Program facilities newsletter, July 2001.; TOPICAL

    International Nuclear Information System (INIS)

    Global Warming and Methane-Global warming, an increase in Earth's near-surface temperature, is believed to result from the buildup of what scientists refer to as ''greenhouse gases.'' These gases include water vapor, carbon dioxide, methane, nitrous oxide, ozone, perfluorocarbons, hydrofluoro-carbons, and sulfur hexafluoride. Greenhouse gases can absorb outgoing infrared (heat) radiation and re-emit it back to Earth, warming the surface. Thus, these gases act like the glass of a greenhouse enclosure, trapping infrared radiation inside and warming the space. One of the more important greenhouse gases is the naturally occurring hydrocarbon methane. Methane, a primary component of natural gas, is the second most important contributor to the greenhouse effect (after carbon dioxide). Natural sources of methane include wetlands, fossil sources, termites, oceans, fresh-waters, and non-wetland soils. Methane is also produced by human-related (or anthropogenic) activities such as fossil fuel production, coal mining, rice cultivation, biomass burning, water treatment facilities, waste management operations and landfills, and domesticated livestock operations (Figure 1). These anthropogenic activities account for approximately 70% of the methane emissions to the atmosphere. Methane is removed naturally from the atmosphere in three ways. These methods, commonly referred to as sinks, are oxidation by chemical reaction with tropospheric hydroxyl ion, oxidation within the stratosphere, and microbial uptake by soils. In spite of their important role in removing excess methane from the atmosphere, the sinks cannot keep up with global methane production. Methane concentrations in the atmosphere have increased by 145% since 1800. Increases in atmospheric methane roughly parallel world population growth, pointing to anthropogenic sources as the cause (Figure 2). Increases in the methane concentration reduce Earth's natural cooling efficiency by trapping more of the outgoing

  11. Radiation damage measurements on CZT drift strip detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Korsbech, Uffe C C;

    2003-01-01

    At DSRI, in collaboration with the cyclotron facility at Copenhagen University Hospital, we have performed a study of radiation effects exposing a 2.7 mm thick CZT drift strip detector to 30 MeV protons. The detector characteristics were evaluated after exposure to a number of fluences in the range....... A numerical model that emulates the physical processes of the charge transport in the CZT detector was used to derive the charge trapping parameter, mutau(e), (the product of charge mobility and trapping time) as a function of fluence. The analysis showed that the electron trapping increased proportionately...

  12. Ionizing radiations and health. Exposures, epidemiological surveillance and sociological monitoring measurements

    International Nuclear Information System (INIS)

    This paper draws attention to the epidemiological effect of natural and artificial ionizing radiation exposures on man. It describes ionizing radiation sources from nuclear facilities and medical establishments. The case here is in the region of La Hague in France where 4800 employees are exposed to ionizing radiations. The topic of leukemia research and thyroid studies for children in the region are discussed. The impact of radiations on fertility, life quality is covered. Finally, national propositions to establish a monitoring measurement system is also discussed including the personnel and the general population exposed

  13. Scientific system for high-resolution measurement of the circumsolar radiation

    International Nuclear Information System (INIS)

    We developed a camera based system for measurements of the circumsolar radiation with a high angular resolution of 0.1 mrad. Subsequent measurements may be taken at intervals as short as 15 s. In this publication we describe the optical system in detail and discuss some aspects of the measurement method. First results from two days of measurement at Freiburg i. Br., Germany, are presented and compared to data from literature. The good results encourage us to perform longer measurement campaigns in future to better understand the influence of circumsolar radiation on the power yield of concentrating photovoltaic systems

  14. European survey on currently existing radiation measurement networks

    International Nuclear Information System (INIS)

    The current situation of measurement networks in Europe is discussed under overriding aspects. This survey is based on current documentation on measurement networks in the following countries: Belgium, Germany, Denmark, France, United Kingdom, Ireland, Italy, Luxembourg, the Netherlands, Austria, Poland, Sweden, Switzerland, Slovak Republic, Spain, Czech Republic and Hungary. The degree of implementation of measurement and monitoring systems on the whole and of measurement networks in particular is evaluated based on existing plannings and is found to differ greatly even after 8 years following the Chernobyl events. The measurement networks of the German IMIS system, for instance, have gone into operation several years ago, whereas the measurement networks and systems in a number of European countries are still in the planning or implementation stages. This fact makes any comparative study quite difficult. The survey focusses therefore on demonstrating major aspects which are fundamental for relevant applications. (orig./HP)

  15. Radiation exposure caused by medical measures: X-rays

    International Nuclear Information System (INIS)

    To estimate the genetic and somatic risks connected with the diagnostic application of X-rays the corresponding population doses must be known. When determining the population doses considerable inaccuracies must be tolerated. Unavoidable is the error resulting from the different doses in the risk organ observed during the same type of examination. The organ dose during an X-ray examination depends on various factors. These dependences are well known, due to systematic examinations in connection with the development of calculation methods. It is, however, only rarely possible to exactly determine all parameters, especially the geometrical ones, during an X-ray examination and to obtain a reliable calculation. Systematic examinations have shown ways to reduce organ doses thus contributing to a general reduction in the radiation exposure and the radiation risks of the population. The risk values given which result from the application of X-rays in diagnosing can only be used as rough ideas which are most probably at the upper limit. (orig./HP)

  16. Measurements of radiation-dose distributions around a slow positron facility

    International Nuclear Information System (INIS)

    Radiation-dose distributions around a slow-positron facility were measured. Radiation doses were measured by the use of Mg2SiO4: Tb TLD's inside and outside the low energy experimental room while intense electrons bombarding the electron-positron converter. By adding lead and borated polyethylene bricks to cover the converter and positron moderator, background radiations in the measurement room were decreased to a large extent. Photon energy spectra were also observed with a high-purity Ge coaxital detector. These measurements proved the effectiveness of the radiation shields made of powdered iron ore. A distinct peak at 511 keV was observed, the origin of which was probably pair-creation process of X rays streamed through a hole drilled in the thick shielding door in order to guide transporting system of slow positrons. (author)

  17. Design And Measurement Of Radiation Exposure Rates At An X-Ray Diagnostic Radiological Unit

    International Nuclear Information System (INIS)

    Every radiation employees suffers radiation exposure risk while doing his job. It is important therefore to investigate the occupational health and safety of radiation employees on its relationship with the design and measurement of radiation exposure rates at an X-ray diagnostic radiological unit in this work, a case study was held on the radiological unit at BP-4 Yogyakarta for patient diagnostics, This research armed to investigate the relationship between the design of radiological unit for X-ray diagnostics and the location of the X-ray machine, based on the distance variable and radiation exposure rate during patient diagnostics. This was performed using radiological unit design data for X-ray diagnostics and the measurement of radiation exposure rates throughout patient diagnostics. The design data can then be used for determining the requirement of primary and secondary shielding materials for radiological unit as well as a calculation basis of radiation exposure rates during patient diagnostics. From the result of the research, it can be concluded that from the occupational health and safety point of view, radiation exposure around the X-ray machines are fairly good, both for the shielding materials in each X-ray room and the radiation exposures received by the workers, because they are far beyond the maximum permittable average limit (16.67 m R/days). (author)

  18. Measurement and simulation of the radiation environment in the lower atmosphere for dose assessment

    International Nuclear Information System (INIS)

    Flying personnel is occupationally exposed to rather high radiation levels due to secondary cosmic radiation. Therefore, the radiation environment induced in the lower atmosphere by galactic and solar cosmic radiation was characterized by means of particle transport calculations using GEANT4. These calculations were validated with continuous measurements of the energy spectra of secondary neutrons with Bonner sphere spectrometers at the Zugspitze mountain and near the North Pole. The response of these instruments was determined with GEANT4 and for the first time experimentally verified at high neutron energies (244 and 387 MeV). Route doses for aircrews along typical long-haul flights were determined for galactic and solar cosmic radiation using most recent data on the magnetospheric field and primary cosmic radiation.

  19. Estimation of optimum sampling period for measurement of solar radiation on photo voltanic generating system

    International Nuclear Information System (INIS)

    The purpose of this research is to obtain the optimum sampling period for evaluating solar photovoltaic generation beforehand. For this purpose, the solar radiation was measured over 1 year at the once per a week. The effect of the sampling period on the integral error of amount of solar radiation was analyzed, and the fractal analysis of the solar radiation was carried out. As a result, the following issues were clarified. Er = 0,0117t and r = 0.00201Qa + 1.934 were obtained as a relational expressions of the sampling period (t) and the integral error (Er) in amount of solar radiation, and of the amount of solar radiation (Qa) and the sampling period (t). Upper limit in the optimum sampling period was the 236 seconds, when allowed integral error of amount of solar radiation was 3%

  20. Radiation Damage of the ATLAS Pixel Sensors Using Leakage Current Measurement System

    CERN Document Server

    Gorelov, I; The ATLAS collaboration

    2013-01-01

    The current measurement system measures directly the leakage current in pixel sensors. The system is integrated with the ATLAS Pixel high voltage delivery system. The system runs as a monitor of a radiation damage of the pixel sensors. The leakage current data collected for the completed data taking period are analyzed. The recent status of the sensor's radiation damage and a comparison with the theoretical predictions are presented.

  1. Nuclear Targets for a Precision Measurement of the Neutral Pion Radiative Width

    CERN Document Server

    Martel, P; McWilliams, R; Lawrence, D; Miskimen, R; Ahmidouch, A; Ambrozewicz, P; Asratyan, A; Baker, K; Benton, L; Bernstein, A; Cole, P; Collins, P; Dale, D; Danagulyan, S; Davidenko, G; Demirchyan, R; Deur, A; Dolgolenko, A; Dzyubenko, G; Evdokimov, A; Feng, J; Gabrielyan, M; Gan, L; Gasparian, A; Glamazdin, O; Goryachev, V; Gyurjyan, V; Hardy, K; Ito, M; Khandaker, M; Kingsberry, P; Kolarkar, A; Konchatnyi, M; Korchin, O; Korsch, W; Kowalski, S; Kubantsev, M; Kubarovski, V; Larin, I; Matveev, V; McNulty, D; Milbrath, B; Minehart, R; Mochalov, V; Mtingwa, S; Nakagawa, I; Overby, S; Pasyuk, E; Payen, M; Pedroni, R; Prok, Y; Ritchie, B; Salgado, C; Sitnikov, A; Sober, D; Stephens, W; Teymurazyan, A; Underwood, J; Vasilev, A; Verebryusov, V; Vishnyakov, V; Wood, M

    2008-01-01

    A technique is presented for precision measurements of the area densities, density * T, of approximately 5% radiation length carbon and 208Pb targets used in an experiment at Jefferson Laboratory to measure the neutral pion radiative width. The precision obtained in the area density for the carbon target is +/- 0.050%, and that obtained for the lead target through an x-ray attenuation technique is +/- 0.43%.

  2. Nuclear Targets for a Precision Measurement of the Neutral Pion Radiative Width

    Energy Technology Data Exchange (ETDEWEB)

    Martel, Philippe; Clinton, Eric; McWilliams, R.; Lawrence, Dave; Miskimen, Rory; Ahmidouch, Abdellah; Ambrozewicz, Pawel; Asaturyan, Arshak; Baker, O.; Benton, LaRay; Bernstein, Aron; Cole, Philip; Collins, Patrick; Dale, Daniel; Danagoulian, Samuel; Davidenko, G.; Demirchyan, Raphael; Deur, Alexandre; DOLGOLENKO, A.; Dzyubenko, Georgiy; Evdokimov, Anatoly; Feng, JIng; Gabrielyan, Marianna; Gan, Liping; Gasparian, Ashot; Glamazdin, Oleksandr; Goryachev, Vladimir; Gyurjyan, Vardan; Hardy, K.; Ito, Mark; Khandaker, Mahbubul; Kingsberry, Paul; Kolarkar, Ameya; Konchatnyi, Mykhailo; Korchin, O.; Korsch, Wolfgang; Kowalski, Stanley; Kubantsev, Mikhail; Kubarovsky, Valery; LARIN, Ilya; MATVEEV, V.; McNulty, Dustin; Milbrath, Brian; Minehart, Ralph; Mochalov, Vasiliy; Mtingwa, Sekazi; Nakagawa, Itaru; Overby, Steven; Pasyuk, Evgueni; Payen, Marvin; Pedroni, Ronald; Prok, Yelena; Ritchie, Barry; Salgado, Carlos; Sitnikov, Anatoly; Sober, Daniel; Stephens, W.; Teymurazyan, Aram; Underwood, Jarreas; VASILIEV, A.; VEREBRYUSOV, V.; Vishnyakov, Vladimir; Wood, Michael

    2009-12-01

    A technique is presented for precision measurements of the area densities, density * T, of approximately 5% radiation length carbon and 208Pb targets used in an experiment at Jefferson Laboratory to measure the neutral pion radiative width. The precision obtained in the area density for the carbon target is +/- 0.050%, and that obtained for the lead target through an x-ray attenuation technique is +/- 0.43%.

  3. Nuclear targets for a precision measurement of the neutral pion radiative width

    Energy Technology Data Exchange (ETDEWEB)

    Martel, P.; Clinton, E.; McWilliams, R.; Lawrence, D. [University of Massachusetts, Amherst (United States); Miskimen, R., E-mail: miskimen@physics.umass.ed [University of Massachusetts, Amherst (United States); Ahmidouch, A.; Ambrozewicz, P. [North Carolina A and T State University (United States); Asratyan, A. [Alikhanov Institute for Theoretical and Experimental Physics (Russian Federation); Baker, K. [Hampton University (United States); Benton, L. [North Carolina A and T State University (United States); Bernstein, A. [Massachusetts Institute of Technology (United States); Cole, P. [Idaho State University (United States); Collins, P. [Arizona State University (United States); Dale, D. [Idaho State University (United States); Danagoulian, S. [North Carolina A and T State University (United States); Davidenko, G. [Alikhanov Institute for Theoretical and Experimental Physics (Russian Federation); Demirchyan, R. [North Carolina A and T State University (United States); Deur, A. [Jefferson Lab (United States); Dolgolenko, A.; Dzyubenko, G. [Alikhanov Institute for Theoretical and Experimental Physics (Russian Federation)

    2009-12-21

    A technique is presented for precision measurements of the area densities, rhoT, of approximately 5% radiation length carbon and {sup 208}Pb targets used in an experiment at Jefferson Laboratory to measure the neutral pion radiative width. The precision obtained in the area density for the carbon target is +-0.050%, and that obtained for the lead target through an X-ray attenuation technique is +-0.43%.

  4. Survey of radiofrequency radiation levels around GSM base stations and evaluation of measurement uncertainty

    International Nuclear Information System (INIS)

    This paper is a summary of broadband measurement values of radiofrequency radiation around GSM base stations in the vicinity of residential areas in Belgrade and 12 other cities in Serbia. It will be useful for determining non-ionizing radiation exposure levels of the general public in the future. The purpose of this paper is also an appropriate representation of basic information on the evaluation of measurement uncertainty. (author)

  5. History of satellite missions and measurements of the Earth Radiation Budget (1957-1984)

    Science.gov (United States)

    House, F. B.; Gruber, A.; Hunt, G. E.; Mecherikunnel, A. T.

    1986-01-01

    The history of satellite missions and their measurements of the earth radiation budget from the beginning of the space age until the present time are reviewed. The survey emphasizes the early struggle to develop instrument systems to monitor reflected shortwave and emitted long-wave exitances from the earth, and the problems associated with the interpretation of these observations from space. In some instances, valuable data sets were developed from satellite measurements whose instruments were not specifically designed for earth radiation budget observations.

  6. Measurement of regional compliance using 4DCT images for assessment of radiation treatment1

    OpenAIRE

    Zhong, Hualiang; Jin, Jian-Yue; Ajlouni, Munther; Movsas, Benjamin; Chetty, Indrin J.

    2011-01-01

    Purpose: Radiation-induced damage, such as inflammation and fibrosis, can compromise ventilation capability of local functional units (alveoli) of the lung. Ventilation function as measured with ventilation images, however, is often complicated by the underlying mechanical variations. The purpose of this study is to present a 4DCT-based method to measure the regional ventilation capability, namely, regional compliance, for the evaluation of radiation-induced lung damage.

  7. A high dynamic radiation measurements instrument : the Bolometric Oscillation Sensor (BOS)

    OpenAIRE

    Zhu, P.; Ruymbeke, M. Van; Karatekin, Ö.; Noël, J.-P.; Thuillier, G.; S. Dewitte; Chevalier, A.; C. Conscience; Janssen, E.; M. Meftah; Irbah, A.

    2015-01-01

    The Bolometric Oscillation Sensor (BOS) is a broadband radiation measurement instrument onboard the PICARD satellite that was active between 2010 and 2014. The main detector is a thermistor attached black coated surface, which was permanently exposed to space without any optical and aperture accessories. The temperature measurements are used within a transfer function to determine variations in incoming solar irradiance as well as the terrestrial radiation. In the present ar...

  8. A unified approach to deconvolution radiation spectra measured by radiochromic films

    Directory of Open Access Journals (Sweden)

    Stančić Velimir A.

    2002-01-01

    Full Text Available A method for the evaluation of energy distribution of a radiation source on the basis of measured space distribution of deposited energy is proposed. The measured data were obtained by using radiochromic films. Mathematical modeling is defined as a Fredholm integral equation inversion problem. Negative solutions were treated as an additional condition expressed through undefined energy group boundaries, caused by virtue of the physical phenomenon of statistical uncertainty. Examples are given of the electron source and neutron radiation field.

  9. Measurements of Small Exposures of Gamma Radiation with CaSO4:Mn Radiothermoluminescence

    International Nuclear Information System (INIS)

    A system for measurements of small exposures of gamma radiation using CaSO4:Mn thermoluminescence has been developed. The construction and performance of a read-out apparatus is described as well as the construction and characteristics of a simple dosimeter. The reproducibility of the method at various exposures is estimated. 20 μR of 1 MeV gamma radiation can be measured with a reproducibility within ± 50 % (standard deviation)

  10. Analysis of dose measurement other than the radiation protection during the radiographic examination

    OpenAIRE

    Kim, Ki-Youl; Cho, Jae-Hwan; Lee, Hae-Kag

    2014-01-01

    Objectives The study measured the dose on body regions that were not shielded to protect from radiation exposure during the general procedure, with the goal of providing basic radiation dose data for radiological technologists who perform the radiographic examination. Materials and methods Shooting parts with the phantom were similar to human tissues using general shooting equipment in the general examination room. The scattered rays were measured with the ion chamber. The hand received the h...

  11. Dose equivalent measurements in a strongly pulsed high-energy radiation field

    CERN Document Server

    Mayer, S; Kyllonen, J E; Menzel, Hans Gregor; Otto, Thomas

    2004-01-01

    The stray radiation field outside the shielding of high-energy accelerators comprises neutrons, photons and charged particles with a wide range of energies. Often, accelerators operate by accelerating and ejecting short pulses of particles, creating an analogue, pulsed radiation field. The pulses can be as short as 10 mu s with high instantaneous fluence rates and dose rates. Measurements of average dose equivalent (rate) for radiation protection purposes in these fields present a challenge for instrumentation. The performance of three instruments (i.e. a recombination chamber, the Sievert Instrument and a HANDITEPC) measuring total dose equivalent is compared in a high-energy reference radiation field (CERF) and a strongly pulsed, high-energy radiation field at the CERN proton synchrotron (PS).

  12. A Method for Ultrashort Electron Pulse Shape-Measurement Using Coherent Synchrotron Radiation

    CERN Document Server

    Geloni, G A; Schneidmiller, E A; Yurkov, M V

    2003-01-01

    In this paper we discuss a method for nondestructive measurements of the longitudinal profile of sub-picosecond electron bunches for X-Ray Free Electron Lasers (XFELs). The method is based on the detection of the Coherent Synchrotron Radiation (CSR) spectrum produced by a bunch passing a dipole magnet system. This work also contains a systematic treatment of synchrotron radiation theory which lies at the basis of CSR. Standard theory of synchrotron radiation uses several approximations whose applicability limits are often forgotten: here we present a systematic discussion about these assumptions. Properties of coherent synchrotron radiation from an electron moving along an arc of a circle are then derived and discussed. We describe also an effective and practical diagnostic technique based on the utilization of an electromagnetic undulator to record the energy of the coherent radiation pulse into the central cone. This measurement must be repeated many times with different undulator resonant frequencies in or...

  13. Basic evaluation of signal transmission in a real-time internal radiation dose measurement system

    International Nuclear Information System (INIS)

    In radiation therapy, excessive exposure to radiation occurs because the dose actually delivered to the tumor is not known. As a result, a patient suffers from side effects. To solve this problem, a system is needed in which the delivered dose is measured inside the body and the dose data are transmitted from inside to outside of the body during radiation therapy. If such a system is realized, it will be possible to treat cancer safely and effectively. The proposed real-time internal radiation dose measurement system consists of an implantable dosimeter, a wireless communication system, and a wireless feeding system. In this study, a wireless communication system that uses magnetic fields was investigated. As a result, a communication distance of 200 mm was obtained. It was confirmed that radiation dose data could be transmitted outside the body when the communication distance is the required 200 mm. (author)

  14. INDIRECT SENSING OF PLANT CANOPY STRUCTURE WITH SIMPLE RADIATION MEASUREMENTS

    Science.gov (United States)

    A technique for indirectly sensing canopy structure from simple, manageable measurements of sunlight transmission through the canopy is examined. he need for reliable measures of leaf area Index and leaf angle distributions has been clearly established in the literature for many ...

  15. Environmental radioactivity and radiation measurements in Taiwan, Republic of China

    International Nuclear Information System (INIS)

    The rather high radium content in the Peitou hot spring presents a special feature in Taiwan's natural radiation environment. The inhabitants of Peitou usually use the hot spring for both bathing and drinking. Because of the existence of the hot spring, Peitou is also a well-known resort which attracts many tourists and visitors each day. However, it is not advisable to use the hot spring for drinking, as radium-226 content is 16 times higher than the rest of Taiwan's water. Before 1964 the fallout in Taiwan was due to the nuclear weapon tests in Siberia. However, after 1964 the fallout contamination in Taiwan was due to the nuclear weapon tests at Lop Nor. As compared with other countries such as Japan and U.S.A., the agricultural products in Taiwan have shown a rather low fallout content. (U.S.)

  16. Measurements of radiation effects on a 4 Mb PSRAM memory

    Energy Technology Data Exchange (ETDEWEB)

    Gonçalez, Odair Lelis; Pereira Junior, Evaldo Carlos Fonseca; Vaz, Rafael Galhardo; Pereira, Marlon Antonio [Instituto de Estudos Avançados (IEAv/DCTA) - São José dos Campos, SP (Brazil); Wirth, Gilson Inácio; Both, Thiago Hanna [Universidade Federal do Rio Grande do Sul (UFRGS) - Porto Alegre, RS (Brazil)

    2014-11-11

    The results of a static test of total ionizing dose (TID) effects on an ISSI 4Mb PSRAM memory are reported in this work. The irradiation was performed at the IEAv’s Laboratory of Ionizing Radiation with 1.17 and 1.32 MeV gamma-rays from a {sup 60}Co source at a dose rate of 2.5 krad/h up to an accumulated dose of 215.7 krad. The TID threshold for bit flip found in this experiment was 52.5 krad. From a sampling of 4096 memory addresses it was estimated a bit flip rate of approximately 50% at an accumulated dose of 215.7 krad.

  17. Measurement of $\\alpha_{s}$ with Radiative Hadronic Events

    CERN Document Server

    Abbiendi, G; Åkesson, P F; Alexander, G; Anagnostou, G; Anderson, K J; Asai, S; Axen, D; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, R J; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, S; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brown, R M; Burckhart, H J; Campana, S; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, A; Cuffiani, M; Dado, S; Dallavalle, M; de Roeck, A; De Wolf, E A; Desch, K; Dienes, B; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, F; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, J; Gruwé, M; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Herten, G; Heuer, R D; Hill, J C; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanzaki, J; Karlen, D; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krasznahorkays, A Jr; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Lafferty, G D; Landsman, H; Lanske, D; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Mashimo, T; Mättig, P; McKenna, J; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Meyer, N; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; O'Neale, S W; Oh, A; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Pooth, O; Przybycien, M; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rossi, A M; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schiecks, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, J; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

    2008-01-01

    Hadronic final states with a hard isolated photon are studied using data taken at centre-of-mass energies around the mass of the Z0 boson with the OPAL detector at LEP. The strong coupling alpha S is extracted by comparing data and QCD predictions for event shape observables at average reduced centre-of-mass energies ranging from 24 GeV to 78 GeV, and the energy dependence of alpha S is studied. Our results are consistent with the running of alpha S as predicted by QCD and show that within the uncertainties of our analysis event shapes in hadronic Z0 decays with hard and isolated photon radiation can be described by QCD at reduced centre-of-mass energies. Combining all values from different event shape observables and energies gives alpha S (Mz)=0.1182 pm 0.0015(stat.) pm 0.0101(syst.).

  18. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale

    International Nuclear Information System (INIS)

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value

  19. Measurement and analysis of the electric field radiation in pulsed power system of linear induction accelerator

    International Nuclear Information System (INIS)

    The close of high voltage switch in pulsed power system of linear induction accelerator often radiates strong transient electric field, which may influence ambient sensitive electric equipment, signals and performance of other instruments, etc. By performing gridded measurement around the Marx generator, the general distribution law and basic characters of electric field radiation are summarized. The current signal of the discharge circuit is also measured, which demonstrates that the current and the radiated electric field both have a resonance frequency about 150 kHz, and contain much higher frequency components. (authors)

  20. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale

    Science.gov (United States)

    Kawamura, Yoshiyuki

    2016-01-01

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

  1. The implementation of a therapy radiation dose measurement system using a microcomputer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Hun; Chai, Jong Seo; Kim, Yu Seok; Hong, Seong Seok; Lee, Min Yong [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-12-01

    In this paper, the therapy radiation dose measurement system has been implemented by using a microcomputer after radiation was irradiated on diodes from the MM22 microtron accelerator. We have displayed 7-channel diode output values on the LCD after processing those in the 80196 MCU (Micro Computer Unit). Signal processing has been performed in the pulse mode because we can process the signal fast and use it to perform portal image by increasing a number of diode channels in the future. In order to verify the microcomputer based radiation measurement system of diodes, diode output values were compared with that of semiconductor. (author). 6 refs., 11 figs.

  2. The implementation of a therapy radiation dose measurement system using a microcomputer

    International Nuclear Information System (INIS)

    In this paper, the therapy radiation dose measurement system has been implemented by using a microcomputer after radiation was irradiated on diodes from the MM22 microtron accelerator. We have displayed 7-channel diode output values on the LCD after processing those in the 80196 MCU (Micro Computer Unit). Signal processing has been performed in the pulse mode because we can process the signal fast and use it to perform portal image by increasing a number of diode channels in the future. In order to verify the microcomputer based radiation measurement system of diodes, diode output values were compared with that of semiconductor. (author). 6 refs., 11 figs

  3. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale.

    Science.gov (United States)

    Kawamura, Yoshiyuki

    2016-01-01

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value. PMID:26827362

  4. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Yoshiyuki [Department of Intelligent Mechanical Engineering, Fukuoka Institute of Technology, 3-30-1 Wajirohigashi, Higashiku, Fukuoka 811-0295 (Japan)

    2016-01-15

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO{sub 2}) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO{sub 2} gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

  5. Precision measurement and determinations of laser radiation coherence by digital processing of their interferograms

    CERN Document Server

    Tikhonov, Eugene A

    2012-01-01

    The method of digital processing of laser radiation interference pattern with the digital microscope and original two-beam interferometer with the phase Bragg grating as the amplitude beam splitter for a quantitative determination of the spatial and temporary coherence module of radiation is described. The digital processing of the interference pattern images was carried out with known software algorithms. Principles and functionality of a measurement procedures are demonstrated on measuring of the radiation coherence of several gas, solid-state and diode lasers.

  6. An overview of global solar radiation measurements in Ghardaia area, south Algeria

    OpenAIRE

    Kacem Gairaa, Yahia Bakelli

    2011-01-01

    This paper presents an overview of actual solar radiation data measurements in Ghardaia site (32.360 N, 3.810 W, 450 m above MSL). Global solar radiation and surface temperatures were measured and analyzed for one complete year from 1 January-31December 2005. The data thus recorded are compared with corresponding data of the 22-year average of NASA's surface meteorology and solar energy-model. Hourly, daily and monthly solar radiation was made from five-minute recorded by EKO Pyranometer. The...

  7. Workshop on measurement quality assurance for ionizing radiation: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Heath, J.A.; Swinth, K.L. [comps.

    1993-12-31

    This workshop was held to review the status of secondary level calibration accreditation programs, review related measurement accreditation programs, document lessons learned, and to present changes in programs due to new national priorities involving radioactivity measurements. Contents include: fundamentals of measurement quality assurance (MQA), standards for MQA programs; perspectives and policies; complete MQA programs; future MQA programs; QA/QC programs--radioactivity; QA/QC programs--dosimetry; laboratory procedures for QA/QC; in-house control of reference dosimetry laboratories; in-house controls of radioactivity laboratories; and poster session. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  8. Workshop on measurement quality assurance for ionizing radiation: Proceedings

    International Nuclear Information System (INIS)

    This workshop was held to review the status of secondary level calibration accreditation programs, review related measurement accreditation programs, document lessons learned, and to present changes in programs due to new national priorities involving radioactivity measurements. Contents include: fundamentals of measurement quality assurance (MQA), standards for MQA programs; perspectives and policies; complete MQA programs; future MQA programs; QA/QC programs--radioactivity; QA/QC programs--dosimetry; laboratory procedures for QA/QC; in-house control of reference dosimetry laboratories; in-house controls of radioactivity laboratories; and poster session. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  9. Radiation Protection Research: Low-level Radioactivity Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hurtgen, C

    2000-07-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advice the nuclear and non-nuclear industry in matters concerning radioactive contamination and/or low-level radioactivity measurements; (4) to maintain the quality assurance system according to the EN45001 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 1999 are reported. Particular emphasis is SCK-CEN's contribution to the EULEP-EURADOS Action Group on 'Derivation of parameter values for application in the new model of the human respiratory tract for occupational exposure'.

  10. Measurements and theoretical calculations of diffused radiation and atmosphere lucidity

    International Nuclear Information System (INIS)

    Align with other environment friendly renewable energy sources solar energy is widely used in the world. Also in Latvia solar collectors are used. However, in Latvia because of its geographical and climatic conditions there are some specific features in comparison with traditional solar energy using countries. These features lead to the necessity to pay more attention to diffused irradiance. Another factor affecting the received irradiance of any surface is lucidity of atmosphere. This factor has not been studied in Latvia yet. This article deals with evaluation of diffused irradiance, and also of lucidity of atmosphere. The diffused irradiance can be measured directly or as a difference between the global irradiance and the beam one. The lucidity of atmosphere can be calculated from the measurements of both global and beam irradiance, if the height of the sun is known. Therefore, measurements of both global and beam irradiance have been carried out, and the diffused irradiance calculated as a difference between the global irradiance and the beam one. For measuring of the global irradiance the dome solarimeter has been used. For measuring of the direct irradiance tracking to sun pirheliometer has been used. The measurements were performed in Riga from October 2008 till March 2009. The measurements were executed automatically after every 5 minutes. The obtained results have been analyzed taking into account also the data on nebulosity from the State agency Latvian Environment, Geology and Meteorology Agency. Also efforts to calculate theoretically the diffused irradiance from the height of the sun and the data of the nebulosity have been done. These calculated values have been compared with the measured ones. Good accordance is obtained. (author)

  11. Radiation-induced statistical uncertainty in the threshold voltage measurement of MOSFET dosimeters

    International Nuclear Information System (INIS)

    The results of a recent study on the limiting uncertainties in the measurement of photon radiation dose with MOSFET dosimeters are reported. The statistical uncertainty in dose measurement from a single device has been measured before and after irradiation. The resulting increase in 1/f noise with radiation dose has been investigated via various analytical models. The limit of uncertainty in the ubiquitous linear trend of threshold voltage with dose has been measured and compared to two nonlinear models. Inter-device uncertainty has been investigated in a group of 40 devices, and preliminary evidence for kurtosis and skewness in the distributions for devices without external bias has been observed

  12. Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

    Science.gov (United States)

    Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

    2014-01-24

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment. PMID:24324275

  13. Snowpack snow water equivalent measurement using the attenuation of cosmic gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Osterhuber, R. [Univ. of California, Soda Springs, CA (United States). Central Sierra Snow Lab.; Fehrke, F. [California Dept. of Water Resources, Sacramento, CA (United States); Condreva, K. [Sandia National Labs., Livermore, CA (United States)

    1998-05-01

    Incoming, background cosmic radiation constantly fluxes through the earth`s atmosphere. The high energy gamma portion of this radiation penetrates many terrestrial objects, including the winter snowpack. The attenuation of this radiation is exponentially related to the mass of the medium through which it penetrates. For the past three winters, a device measuring cosmic gamma radiation--and its attenuation through snow--has been installed at the Central Sierra Snow Laboratory, near Donner Pass, California. This gamma sensor, measuring energy levels between 5 and 15 MeV, has proved to be an accurate, reliable, non-invasive, non-mechanical instrument with which to measure the total snow water equivalent of a snowpack. This paper analyzes three winters` worth of data and discusses the physics and practical application of the sensor for the collection of snow water equivalent data from a remote location.

  14. Snowpack snow water equivalent measurement using the attenuation of cosmic gamma radiation

    International Nuclear Information System (INIS)

    Incoming, background cosmic radiation constantly fluxes through the earth's atmosphere. The high energy gamma portion of this radiation penetrates many terrestrial objects, including the winter snowpack. The attenuation of this radiation is exponentially related to the mass of the medium through which it penetrates. For the past three winters, a device measuring cosmic gamma radiation--and its attenuation through snow--has been installed at the Central Sierra Snow Laboratory, near Donner Pass, California. This gamma sensor, measuring energy levels between 5 and 15 MeV, has proved to be an accurate, reliable, non-invasive, non-mechanical instrument with which to measure the total snow water equivalent of a snowpack. This paper analyzes three winters' worth of data and discusses the physics and practical application of the sensor for the collection of snow water equivalent data from a remote location

  15. Discovery of A New Retrograde Trans-Neptunian Object: Hint of A Common Orbital Plane for Low Semi-Major Axis, High Inclination TNOs and Centaurs

    CERN Document Server

    Chen, Ying-Tung; Holman, Matthew J; Payne, Matthew J; Fraser, Wesley C; Lacerda, Pedro; Ip, Wing-Huen; Chen, Wen-Ping; Kudritzki, Rolf-Peter; Jedicke, Robert; Wainscoat, Richard J; Tonry, John L; Magnier, Eugene A; Waters, Christopher; Kaiser, Nick; Wang, Shiang-Yu; Lehner, Matthew

    2016-01-01

    Although the majority of Centaurs are thought to have originated in the scattered disk, with the high-inclination members coming from the Oort cloud, the origin of the high inclination component of trans-Neptunian objects (TNOs) remains uncertain. We report the discovery of a retrograde TNO, which we nickname "Niku", detected by the Pan-STARRS 1 Outer Solar System Survey. Our numerical integrations show that the orbital dynamics of Niku are very similar to that of 2008 KV$_{42}$ (Drac), with a half-life of $\\sim 500$ Myr. Comparing similar high inclination TNOs and Centaurs ($q > 10$ AU, $a 60^\\circ$), we find that these objects exhibit a surprising clustering of ascending node, and occupy a common orbital plane. This orbital configuration has high statistical significance: 3.8-$\\sigma$. An unknown mechanism is required to explain the observed clustering. This discovery may provide a pathway to investigate a possible reservoir of high-inclination objects.

  16. Satellite Infrared Radiation Measurements Prior to the Major Earthquakes

    Science.gov (United States)

    Ouzounov, Dimitar; Pulintes, S.; Bryant, N.; Taylor, Patrick; Freund, F.

    2005-01-01

    This work describes our search for a relationship between tectonic stresses and increases in mid-infrared (IR) flux as part of a possible ensemble of electromagnetic (EM) phenomena that may be related to earthquake activity. We present and &scuss observed variations in thermal transients and radiation fields prior to the earthquakes of Jan 22, 2003 Colima (M6.7) Mexico, Sept. 28 .2004 near Parkfield (M6.0) in California and Northern Sumatra (M8.5) Dec. 26,2004. Previous analysis of earthquake events has indicated the presence of an IR anomaly, where temperatures increased or did not return to its usual nighttime value. Our procedures analyze nighttime satellite data that records the general condtion of the ground after sunset. We have found from the MODIS instrument data that five days before the Colima earthquake the IR land surface nighttime temperature rose up to +4 degrees C in a 100 km radius around the epicenter. The IR transient field recorded by MODIS in the vicinity of Parkfield, also with a cloud free environment, was around +1 degree C and is significantly smaller than the IR anomaly around the Colima epicenter. Ground surface temperatures near the Parkfield epicenter four days prior to the earthquake show steady increase. However, on the night preceding the quake, a significant drop in relative humidity was indicated, process similar to those register prior to the Colima event. Recent analyses of continuous ongoing long- wavelength Earth radiation (OLR) indicate significant and anomalous variability prior to some earthquakes. The cause of these anomalies is not well understood but could be the result of a triggering by an interaction between the lithosphere-hydrosphere and atmospheric related to changes in the near surface electrical field and/or gas composition prior to the earthquake. The OLR anomaly usually covers large areas surrounding the main epicenter. We have found strong anomalies signal (two sigma) along the epicentral area signals on Dec 21

  17. Some aspects of RF radiation safety guidelines on urgent protective measures in case of radiation emergency at NPP

    International Nuclear Information System (INIS)

    Full text: The work is aimed at developing a decision making strategy and tools for putting into practice the principles of reasonableness and optimization when applying countermeasures in case of a radiation related accident at a nuclear power plant in RF. The presentation discusses results of the study of the legal framework in the RF for decision making to protect the personnel and public in case of a radiation-related accident Consideration is given to issues of methodological support for emergency response systems at NPPs, as required by the RF radiation safety norms to protect personnel and the public. This work was performed as part of methodological support to the national emergency center of Rosenergoatom comprising several technical support centers on the base of leading institutes with large scientific potential in the fields of nuclear power use, environmental and public protection, radioecology etc. Such centers were set up for scientific and technical support to decision making in case of emergency at NPPs. Specialists of die centers are able to quickly assess the emerging situation and propose a set of measures to minimize damage, drawing on expert judgements. The radiation safety guidelines (NRB-99) lays down requirements and criteria for decision making to protect the public in different phases of a radiation accident which should be used when implementing countermeasures and developing emergency response plans with allowance for specific situation and local conditions. These criteria provide a basis for designating areas of emergency response that would be optimum for specific population points, intervention measures etc. Dealing with these tasks requires development of normative and methodological documentation taking into account both the NRB-99 requirements and international recommendations. In accordance with NRB-99: expected and averted radiation doses are the key criteria to be used in application of any protection measures in radiation

  18. Application of imaging plate to measurement of radiation spatial distribution

    International Nuclear Information System (INIS)

    An imaging plate (IP) was applied to 1) detecting of low-level contamination that was difficult to detect by a conventional way, 2) measurement of spatial distributions of thermal neutrons and 3) profile measurement of fast neutrons and proton beam of low intensity. For 1), a large-size IP (BAS-IIIs) was disposed to the sample, and the position and intensity of the contamination was identified unambiguously by scanning IP. For 2), activation foils were combined with IP to avoid γ-rays from neutron sources and radioactive accelerator components. We placed small gold activation foils at many points of interest in an accelerator room and disposed them on IP after irradiation. This method enables to measure neutron spatial distribution in a single scanning. We extended this method to profiling of fast neutron by using an aluminum plate and proton beams with intensity too low to measure by beam current but too strong to measure by pulse counting by using a thin copper foil. (author)

  19. Radiation measurement of apples produced in Aomori prefecture

    International Nuclear Information System (INIS)

    The activities of seven kinds of apples produced in Aomori prefecture were measured with a high pure Ge detector set in a 15 cm-thick lead shield. The activities of 40K were detected in all samples, but an artificial radioactive nuclide was not detected. The slices of an apple were contacted to an imaging plate for 15 days in a 15 cm-thick lead shield and cross sectional activity distributions were measured. By using the distribution map, the activities of skin, flesh and lead portion of an apple 'Ohrin' were calculated to 0.041, 0.032 and 0.046 Bq/g, respectively. This measuring system will be used for the activity estimations of the farm products, specially apples, because of that many atomic institutions are in operation and in the planning stage on Aomori prefecture. (author)

  20. Reference detectors for low flux optical radiation measurements

    International Nuclear Information System (INIS)

    The parametric down conversion of photons generated in a non-linear crystal gives rise to two correlated photons. Associated to a System of counting of coincidences, this phenomenon makes possible the quantum efficiency measurements of detectors working on photon counting levels, without using neither sources nor detectors of references. This new method was developed at BNMINM with the aim to realize new standards detectors in the field of weak flows. It allows the determination of quantum efficiency with a relative uncertainty of 1,1%. A comparison with the IENGF (Italy) bearing on the quantum determination of efficiency of one of BNM-FNM detectors made possible to confront the exactitude of the measuring equipment. This detector was also made the object of a comparison with the French reference of radiometry, the cryogenic radiometer, the results were in agreement with uncertainties of measurements. (author)

  1. Design Specifications for a Radiation Tolerant Beam Loss Measurement ASIC

    CERN Document Server

    Venturini, G G; Effinger, E; Zamantzas, C

    2009-01-01

    A novel radiation-hardened current digitizer ASIC is in planning stage, aimed at the acquisition of the current signals from the ionization chambers employed in the Beam Loss Monitoring system at CERN. The purpose is to match and exceed the performance of the existing discrete component design, currently in operation in the Large Hadron Collider (LHC). The specifications include: a dynamic range of nine decades, defaulting to the 1 pA-1mA range but adjustable by the user, ability to withstand a total integrated dose of 10 kGy at least in 20 years of operation and user selectable integrating windows, as low as 500 ns. Moreover, the integrated circuit should be able to digitize currents of both polarity with a minimum number of external components and without needing any configuration. The target technology is the IBM 130nm CMOS process. The specifications, the architecture choices and the reasons on which they are based upon are discussed in this paper.

  2. On the measurement of in situ antenna radiation parameters from scattering measurements using a general scattering parametric model

    Science.gov (United States)

    Mendez, Enrique Alberto

    The new concept of antenna radiation center (ARC) is introduced and an empirical method to measure it from complex scattering data is presented. This concept is different from the well-known antenna phase center utilized in reflector antenna applications. A novel and efficient procedure based on a General Parametric Scattering Model (GSPM) is utilized to extract in-situ antenna radiation properties from complex antenna scattering data. This model based measurement approach has the advantage that it only requires two swept frequency scattering measurements in order to obtain antenna RCS, antenna gain and antenna radiation center in its integrated operational environment. The GSPM structure required to accurately extract arbitrary target scattering data is developed based on basic electromagnetic principles. The mathematical model structure consists of an early time response based on a point scattering model and on a late time response based on the Singularity Expansion Method (SEM). Both of these methods are implemented to take into account the target dispersion in a general fashion. Robust signal processing algorithms are utilized to extract the model parameters by exploiting the model symmetry properties in the time and frequency domains. In particular, super-resolution algorithms such as ESPRIT and MUSIC are utilized to extract scattering center location and resonance frequency information, while Least Squares techniques are used to estimate the different model amplitude coefficients as a function of time or frequency in an optimal (i.e. mean square sense) fashion. Theoretical derivations are provided to demonstrate that the GSPM can be utilized to extract antenna gain and radiation center information from scattering data. Synthetic and measured antenna scattering data are utilized to demonstrate the GSPM superior gain and radiation center results over traditional Fourier techniques. Gain transfer measurements results are also compared to the GSPM derived gain

  3. Application of polychromatic X-radiation for density measurements

    International Nuclear Information System (INIS)

    In this study a theory is postulated by means of which quantitative calculations can be made for density measurements by polychromatic X-rays. At the same time, gas densities for the first time were measured qualitatively by means of focused X-rays. The use of polychromatic X-rays allowed the application of low tube voltages, but high intensities. The disadvantages of the electron beam method, i.e., dependence on molecular bonding and excitation states of the electron absorption and the spectral intensity, and failure in the case of electrically conducting absorbers, are avoided by the X-ray technique. (orig./RF)

  4. Radiodiagnostic measurements radiation load of children by chest

    International Nuclear Information System (INIS)

    With the aim of optimisation of the radiographic examinations in paediatric radiology the entrance surface doses measured by chest examinations, as the most frequent procedure for children in Slovakia were surveyed. In this paper the results of measurements and calculations of doses obtained by paediatric patients with ages ranging from newborn to 15 years, who undergone chest radiodiagnostic examinations during the year 1996 are presented.. The obtained results are compared with dose assessment procedures based on total absorbed dose calculations using the published conversion factors between energy impaired to the patient and and entrance surface doses integrated over the beam area

  5. Solar radiation measurements in forests - I. evaluation of methods and instruments

    International Nuclear Information System (INIS)

    Solar energy sustains ecosystems on earth, therefore solar radiation measurements are the basis for ecological research in forests. Silviculturists in particular should be aware at least of the basic principles of radiation distribution in forest vegetation. There has been a rapid development of methods and devices in the field of solar radiation measurement. In the paper, solar radiation is presented as one of the most important ecological resources and factors. The author demonstrates how significant this knowledge is in silviculture. The main topic is the presentation of recognized methods for solar radiation measurement and estimation in forests. Comparing these different methods we find Photosynthetically Usable Radiation (PUR) sensors to be very appropriate for complex research in forest vegetation. It is advantageous to use multiple PUR sensors connected to a computer for data processing. Another method for estimating radiation which has great potential is the one using hemispherical photography. The same principle is applied in a fixed horizontoscope which is particularly appropriate in silvicultural practice

  6. Advances in Atmospheric Radiation Measurements and Modeling Needed to Improve Air Safety

    Science.gov (United States)

    Tobiska, W. Kent; Atwell, William; Beck, Peter; Benton, Eric; Copeland, Kyle; Dyer, Clive; Gersey, Brad; Getley, Ian; Hands, Alex; Holland, Michael; Hong, Sunhak; Hwang, Junga; Jones, Bryn; Malone, Kathleen; Meier, Matthias M.; Mertens, Chris; Phillips, Tony; Ryden, Keith; Schwadron, Nathan; Wender, Stephen A.; Wilkins, Richard; Xapsos, Michael A.

    2015-04-01

    Air safety is tied to the phenomenon of ionizing radiation from space weather, primarily from galactic cosmic rays but also from solar energetic particles. A global framework for addressing radiation issues in this environment has been constructed, but more must be done at international and national levels. Health consequences from atmospheric radiation exposure are likely to exist. In addition, severe solar radiation events may cause economic consequences in the international aviation community due to exposure limits being reached by some crew members. Impacts from a radiation environment upon avionics from high-energy particles and low-energy, thermalized neutrons are now recognized as an area of active interest. A broad community recognizes that there are a number of mitigation paths that can be taken relative to the human tissue and avionics exposure risks. These include developing active monitoring and measurement programs as well as improving scientific modeling capabilities that can eventually be turned into operations. A number of roadblocks to risk mitigation still exist, such as effective pilot training programs as well as monitoring, measuring, and regulatory measures. An active international effort toward observing the weather of atmospheric radiation must occur to make progress in mitigating radiation exposure risks. Stakeholders in this process include standard-making bodies, scientific organizations, regulatory organizations, air traffic management systems, aircraft owners and operators, pilots and crew, and even the public.

  7. Estimation of effective responsivity of AXUV bolometer in ADITYA tokamak by spectrally resolved radiation power measurement

    International Nuclear Information System (INIS)

    The radiation emission from ADITYA Tokamak is routinely measured using AXUV bolometers and the total radiation power loss is estimated from these measurements assuming constant responsivity. This assumption is valid for the current flattop phase of the discharge, where the contribution from long wavelength radiation (> 620 Å) is expected to be small and the AXUV responsivity is almost constant. It is likely that in disruptive discharges, with significant edge radiation, a part of the unaccounted power is in the long wavelength range. A better approach is to experimentally determine an effective responsivity by spectrally resolving the radiation power loss and assigning appropriate weights to spectral ranges. For this purpose, we have installed a multichannel filtered bolometer camera in ADITYA Tokamak. The wide angle view camera houses three single channel AXUV bolometers, of which two view the plasma through different ultraviolet filters and one has an unfiltered view. All the bolometers have the same poloidal view and are located adjacently in the toroidal direction. The initial results of the spectrally resolved bolometer measurements show that the radiation in the spectral range > 1200 Å is significant fraction of the total radiation during the disruptive phase, but doesn't contribute much during the flattop region. An effective average responsivity has been estimated for AXUV bolometer for ADITYA. (author)

  8. Proceedings of the 109th basic science seminar on research for quantum radiation measurement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    In the field of radiation measurement in next century, one of the main themes for researchers will be to develop new radiation detection techniques based on quantum effects. Thus three research projects for development of new neutron detection method using He-Ne laser cells, radiation-resistant optical fibers, and superconducting tunnel junction radiation detectors have been started five years before in our research group for quantum radiation measurement of the advanced science research center (ASRC) of JAERI. The joint workshop `Research for Quantum Radiation Measurement` was held as one of basic science seminars in ASRC on 19-20th of January 1998 on the occasion of the ending of the projects. There were many presentations concerning the above three themes and the participants had a good opportunity to exchange relating research information. This proceedings includes 13 papers of the presentations. It is not only useful to know the present status of advanced study but also very suggestive to see the direction and evolution of `radiation detection techniques based on quantum effects` in the future. (J.P.N.)

  9. Development of thermoluminescent probe for natural radiation measurements in soil

    Energy Technology Data Exchange (ETDEWEB)

    Isabey-Gschwind, R. E-mail: regine.gschwind@pu-pm.univ-fcomte.fr; Makovicka, L.; Klein, D.; Duverger, E.; Voytchev, M

    2001-06-01

    The principal aim of these theoretical and experimental studies is the development and realisation of thermoluminescent (CaSO{sub 4} : Dy) probes for the measurement of gamma radioactivity in soil with the possibility of also evaluating the alpha (especially radon) and gamma contribution to the global response of these thermoluminescent detectors.

  10. Development of thermoluminescent probe for natural radiation measurements in soil

    CERN Document Server

    Isabey-Gschwind, R; Klein, D; Duverger, E; Voytchev, M

    2001-01-01

    The principal aim of these theoretical and experimental studies is the development and realisation of thermoluminescent (CaSO sub 4 : Dy) probes for the measurement of gamma radioactivity in soil with the possibility of also evaluating the alpha (especially radon) and gamma contribution to the global response of these thermoluminescent detectors.

  11. The Dynamics of Centaurs in the Vicinity of the 2:1 Mean Motion Resonance of Neptune and Uranus Trojan Region

    CERN Document Server

    Wood, Jeremy

    2015-01-01

    In this work we present the results of a suite of dynamical simulations following the orbital evolution of 8,022 hypothetical Centaur objects. These Centaurs begin our integrations on orbits in the vicinity of the 2:1 mean motion resonance with Neptune, and we follow their dynamical evolution for a period of 3 Myr under the gravitational influence of a motionless Sun and the four Jovian planets. The great majority of the test particles studied rapidly escaped from the vicinity of the 2:1 mean motion resonance of Neptune and diffused throughout the Solar System. The average libration time of Centaurs in the vicinity of 2:1 mean motion resonance of Neptune was found to be just 27 kyr. Although two particles did remain near the resonance for more than 1 Myr. Upon leaving the vicinity of the 2:1 resonance, the majority of test particles evolved by a process of random walk in semi-major axis, due to repeated close encounters with the giant planets.

  12. Determination of the accuracy and reproducibility of different personal radiation monitors in measuring radiation exposure in a simulated clinical environment

    International Nuclear Information System (INIS)

    Introduction - All staff for whom it is anticipated that their exposure to radiation will be above the public dose limit are designated as radiation workers and are required by the state regulatory body (Radiation Health Branch, Western Australia) to wear personal radiation monitors to monitor this occupational exposure to radiation. Radiation workers involved with the use of diagnostic x-rays at Sir Charles Gairdner Hospital either wear these personal radiation monitors for monthly periods or quarterly periods depending on their work environment and, due to many reasons not related to the efficacy or accuracy of the devices, departments within the hospital choose to wear film badges, thermoluminescent dosimeters (TLDs) or optically stimulated dosimeters (OSLs). It is evident that these devices are not perfect, but they do provide us with a cost-effective way in which to estimate the occupational lifetime dose of radiation workers and to ensure that occupational practices are optimised so as to keep doses as low as reasonably achievable. The aim of this project was to assess the accuracy and reproducibility of different personal radiation monitors across the diagnostic x-ray energy range when exposed to scatter radiation in a simulated clinical environment. Methodology - In order to simulate scatter from a patient, a patient equivalent phantom (PEP) was placed on the table of a Philips Optimus 80 radiographic unit, with the source to-skin distance being set to 80 ffl 1 cm. Once the PEP phantom was in place, a Radcal® 6cc ionisation chamber (which provided the reference dose) was placed adjacent to and 50 ffl 1 cm from the centre of, the PEP phantom. As the direction of scattered photons at low energies is relatively isotropic, the reference dose was acquired simultaneously with the personal radiation monitor doses. That is, the 6cc ionisation chamber and the personal radiation monitor doses were all measured at a distance of 50 ffl 1 cm from the centre of the PEP

  13. Measurement and modeling of external radiation during 1985 from LAMPF [Los Alamos Meson Physics Facility] emissions

    International Nuclear Information System (INIS)

    An array of three portable, pressurized ionization chambers (PICs) continued to measure external radiation levels during 1985 caused by radionuclides emitted from the Los Alamos Meson Physics Facility (LAMPF). A Gaussian-type atmospheric dispersion model, using onsite meteorological and stack release data, was tested during this study. A more complex finite model, which takes into account the contribution of radiation at a receptor from different locations of the passing plume, was also tested. Monitoring results indicate that, as in 1984, a persistent wind up the Rio Grande Valley during the evening and early morning hours is largely responsible for causing the highest external radiation levels to occur to the northeast and north-northeast of LAMPF. However, because of increased turbulent mixing during the day, external radiation levels are generally much less during the day than at night. External radiation levels during 1985 show approximately a 75% reduction over 1984 levels. This resulted from a similar percentage reduction in LAMPF emissions caused by newly implemented emission controls. Comparison of predicted and measured daily external radiation levels indicates a high degree of correlation. The model also gives accurate estimates of measured concentrations over longer time periods. Comparison of predicted and measured hourly values indicates that the model generally tends to overpredict during the day and underpredict at night. 9 refs., 14 figs., 13 tabs

  14. Return glider radiosonde to measure temperature, humidity and radiation profiles through the atmosphere

    Science.gov (United States)

    Kraeuchi, Andreas; Philipona, Rolf

    2015-04-01

    Very promising radiation profile measurements through the atmosphere were made in 2011 with a balloon borne short- and longwave net radiometer. New and improved radiation sensors from Kipp&Zonen are now used in a glider aircraft together with a standard Swiss radiosonde from Meteolabor AG. This new return glider radiosonde (RG-R), is lifted up with double balloon technique to prevent pendulum motion and to keep the radiation instruments as horizontal as possible during the ascent measuring phase. The RG-R is equipped with a mechanism that allows to release the radiosonde at a preset altitude, and an autopilot allowing to fly the radiosonde back to the launch site and to land it savely with a parachute at a preset location. The return glider radiosonde technique as well as new measurement possibilities will be shown. First measurements show temperature, humidity and radiation profiles through the atmosphere up to 30 hPa (24 km) during different atmospheric conditions. Radiation profiles during different daytimes show possibilities with respect to temporal resolution of vertical radiation profiles trough the atmosphere.

  15. Measurement of XUV-absorption spectra of ZnS radiatively heated foils

    CERN Document Server

    Kontogiannopoulmos, Nikolaos; Thais, Frédéric; Chenais-Popovics, Claude; Sauvan, Pascal; Schott, R; Fölsner, Wolfgang; Arnault, Philippe; Poirier, Michel; Blenski, Thomas

    2008-01-01

    Time-resolved absorption of zinc sulfide (ZnS) and aluminum in the XUV-range has been measured. Thin foils in conditions close to local thermodynamic equilibrium were heated by radiation from laser-irradiated gold spherical cavities. Analysis of the aluminum foil radiative hydrodynamic expansion, based on the detailed atomic calculations of its absorption spectra, showed that the cavity emitted flux that heated the absorption foils corresponds to a radiation temperature in the range 55 60 eV. Comparison of the ZnS absorption spectra with calculations based on a superconfiguration approach identified the presence of species Zn6+ - Zn8+ and S5+ - S6+. Based on the validation of the radiative source simulations, experimental spectra were then compared to calculations performed by post-processing the radiative hydrodynamic simulations of ZnS. Satisfying agreement is found when temperature gradients are accounted for.

  16. Radiochromic Plastic Films for Accurate Measurement of Radiation Absorbed Dose and Dose Distributions

    DEFF Research Database (Denmark)

    McLaughlin, W. L.; Miller, Arne; Fidan, S.;

    1977-01-01

    Thin radiochromic dye films are useful for measuring large radiation absorbed doses (105–108 rads) and for high-resolution imaging of dose patterns produced by penetrating radiation beams passing through non-homogeneous media. Certain types of amino-substituted triarylmethane cyanides dissolved in...... polymeric solutions can be cast into flexible free-standing thin films of uniform thickness and reproducible response to ultraviolet and ionizing radiation. The increase in optical density versus energy deposited by radiation is linear over a wide range of doses and is for practical purposes independent of...... dose rate (1–1014 rad s−1). Upon irradiation of the film, the profile of the radiation field is registered as a permanent colored image of the dose distribution. Unlike most other types of dyed plastic dose meters, the optical density produced by irradiation is in most cases stable for periods of at...

  17. Field soil-water properties measured through radiation techniques

    International Nuclear Information System (INIS)

    This report shows a major effort to make soil physics applicable to the behaviour of the field soils and presents a rich and diverse set of data which are essential for the development of effective soil-water management practices that improve and conserve the quality and quantity of agricultural lands. This piece of research has shown that the neutron moisture meter together with some complementary instruments like tensiometers, can be used not only to measure soil water contents but also be extremely handy to measure soil hydraulic characteristics and soil water flow. It is, however, recognized that hydraulic conductivity is highly sensitive to small changes in soil water content and texture, being extremely variable spatially and temporally

  18. Radiation measurement system by means of digital oscilloscope

    International Nuclear Information System (INIS)

    As one of the application on digital waveform processing studies, a system that acquires digital waveform data by using digital oscilloscope have been constructed. As an example for measurement with this system, the decay times, pulse shape discrimination based on the pulse shape analysis and FWHM by the digital gated-integration method were measured. Pulse height analysis using digital oscilloscope is also effective similarly to measurements with MCA. Scintillation decay times derived for GSO and BaF2 scintillator were reasonable to the known reference values. It is evident that the intensity of these two main decay components and their decay time depend on the Ce concentration in GSO scintillators. Concerning to the pulse shape discrimination its possibility was indicated in the observed difference in the fast and slow component of the signals from BaF2 scintillator. The transfer rate from the digital oscilloscope to PC did not reach to the performance of the full rate of 200 Kbytes/s in the GP-IB standard. (S.Y.)

  19. Winter radiation extinction and reflection in a boreal pine canopy: measurements and modelling

    International Nuclear Information System (INIS)

    the snow cover surface became positive when daily mean solar angles exceeded 22° in late March. Hence, canopy structure and solar angle control the net radiation at the snow cover surface during clear sky conditions and will govern the timing and rate of snow melt. Models of intercepted snow sublimation and forest snow melt could beneficially incorporate the canopy radiation balance, which can be extrapolated to stands of various canopy densities, coverage and heights in a physically based manner. Such models could hence avoid ‘empirical’ temperature index measures that cannot be extrapolated with confidence. (author)

  20. A small space radiation monitor capable of measuring multiple ISD-VGS values of MOSFET

    International Nuclear Information System (INIS)

    A small space radiation monitor capable of taking measurements of gate voltages of MOSFET for various drain currents has been developed for flight experiments aboard satellites. Measuring multiple ISD-VGS values of MOSFET is expected to provide better understanding of the electronic response to ionizing radiation in space. In particular, separating the effects of oxide charge densities, interface charge densities, and temperatures is anticipated for the accurate determination of total ionizing dose. Description of the instrumentation for space-borne measurements is given, along with a summary of the anticipated results from this experiment. (author)

  1. Method for automatic drift stabilization in radiation measurement with a detector

    International Nuclear Information System (INIS)

    For radiometric measurement of material properties, e.g. a density measurement according to the irradiation method, the reference source of radiation serves at the same time as radiation source for the measurement. The source consists e.g. of 137Cs. The pulse amplitude spectrum contains at least one discrete line. A control device keeps the pulse rate supplied by an integral discriminator constant. For stabilizing purposes the desired value of the control device is preset in such a manner that the pulse rate is smaller than the total pulse rate of the most energetic line (discrete line) in the pulse amplitude spectrum. (DG)

  2. Open-Path FTIR Spectral Radiation Intensity Of Hot Combustion Gases – Measurement And Interpretation

    Directory of Open Access Journals (Sweden)

    Cięszczyk Sławomir

    2015-06-01

    Full Text Available Spectral remote sensing is a very popular method in atmospheric monitoring. The paper presents an approach that involves mid-infrared spectral measurements of combustion processes. The dominant feature in this spectral range is CO2 radiation, which is used to determine the maximum temperature of nonluminous flames. Efforts are also made to determine the temperature profile of hot CO2, but they are limited to the laboratory conditions. The paper presents an analysis of the radiation spectrum of a non-uniform-temperature gas environment using a radiative transfer equation. Particularly important are the presented experimental measurements of various stages of the combustion process. They allow for a qualitative description of the physical phenomena involved in the process and therefore permit diagnostics. The next step is determination of a non-uniform-temperature profile based on the spectral radiation intensity with the 8 m optical path length.

  3. Agricultural measures to reduce radiation doses to man caused by severe nuclear accidents

    International Nuclear Information System (INIS)

    Agricultural land and products may become contaminated after a severe nuclear accident. If radiation doses to man caused by the ingestion of contaminated agricultural products from such areas will be unacceptably high, measures to reduce this radiation dose will have to be taken. Radiation doses to man can be estimated by using models which describe quantitatively the transfer of radionuclides through the biosphere. The following processes and pathways are described in this study: accidental releases into atmospheric environments and subsequent nearby deposition; contamination of crops by direct deposition and the subsequent short term pathway (e.g. grass-cow-milk-man); contamination of soil and the subsequent long term pathway (e.g. soil-crop-man, soil-grass-cattle-milk/meat-man). Depending on the degree of contamination and on the estimated radiation doses to man, various measures are advised. (Auth.)

  4. Evaluation of long-term global radiation measurements in Denmark and Sweden

    DEFF Research Database (Denmark)

    Skalík, Lukáš; Lulkovičová, Otília; Furbo, Simon;

    The climate, especially global radiation is one of the key factors influencing the energy yield of solar energy systems. In connection with planning and optimization of energy efficient buildings and solar energy systems it is important to know the climate data of the area where the buildings....../systems are located. This study is based on yearly and monthly values of global radiation based on measurements from a climate station placed on the roof of building 119 at Technical University of Denmark in Kgs. Lyngby, from different Danish climate stations runned by Danish Meteorological Institute and from...... different Swedish climate stations of Swedish Meteorological and Hydrological Institute. The global horizontal radiation has been measured for a high number of years at all of these stations. The values show a tendency of increased annual global radiation, most likely due to decreased pollution of the...

  5. In situ radiation measurements at the former Soviet Nuclear Test Site

    International Nuclear Information System (INIS)

    A team from the Remote Sensing Laboratory conducted a series of in situ radiological measurements at the former Soviet Nuclear Test Site near Semipalatinsk, Kazakhstan, during the period of July 21-30, 1994. The survey team measured the terrestrial gamma radiation at selected areas on the site to determine the levels of natural and man-made radiation. The survey was part of a cooperative effort between the United States team and teams of radiation scientists from the National Nuclear Center of the Republic of Kazakhstan and the V.G. Khlopin Radium Institute in St. Petersburg, Russia. In addition to in situ radiation measurements made by the United States and Russian teams, soil samples were collected and analyzed by the Russian and Kazakhstani teams. All teams conducted their measurements at ten locations within the test site. The United States team also made a number of additional measurements to locate and verify the positions of three potential fallout plumes containing plutonium contamination from nonnuclear tests. In addition, the United States team made several measurements in Kurchatov City, the housing area used by personnel and their families who work(ed) at the test sites. Comparisons between the United States and Russian in situ measurements and the soil sample results are presented as well as comparisons with a Soviet aerial survey conducted in 1990-1991. The agreement between the different types of measurements made by all three countries was quite good

  6. Spectral measurements of fluctuating ω/sub pe/ radiation from Alcator C tokamak

    International Nuclear Information System (INIS)

    High resolution spectral measurements have been made of the fluctuating electron plasma frequency (ω/sub pe/) radiation from Alcator C. Three techniques have been used in making the measurements. Features as narrow as 350 kHz have been observed (Δf/f approx. = 6 x 10-6), impling that a highly coherent process is responsible for the emission

  7. Project and construction of a measurement system and nuclear radiations analysis

    International Nuclear Information System (INIS)

    A counting system was designed and built, aiming to: detect and measure nuclear radiations using a Geiger-Mueller counter; and to measure the amplitudes of pulses from either a proportional or a NaI detector. The results obtained of the Cs-137 and Co-60 energy spectra were compared with results obtained from other researches. (Author)

  8. Plasma scattering of electromagnetic radiation theory and measurement techniques

    CERN Document Server

    Froula, Dustin H; Luhmann, Neville C Jr; Sheffield, John

    2011-01-01

    This work presents one of the most powerful methods of plasma diagnosis in exquisite detail to guide researchers in the theory and measurement techniques of light scattering in plasmas. Light scattering in plasmas is essential in the research and development of fusion energy, environmental solutions, and electronics.Referred to as the "Bible" by researchers the work encompasses fusion and industrial applications essential in plasma research. It is the only comprehensive resource specific to the plasma scattering technique. It provides a wide-range of experimental examples and discussion of the

  9. Deviating measurements in radiation protection. Legal assessment of deviations in radiation protection measurements; Messabweichungen im Strahlenschutz. Rechtliche Bewertung von Abweichungen bei Strahlenschutzmessungen

    Energy Technology Data Exchange (ETDEWEB)

    Hoegl, A.

    1996-07-01

    This study investigates how, from a legal point of view, deviations in radiation protection measurements should be treated in comparisons between measured results and limits stipulated by nuclear legislation or goods transport regulations. A case-by-case distinction is proposed which is based on the legal concequences of the respective measurement. Commentaries on nuclear law contain no references to the legal assessment of deviating measurements in radiation protection. The examples quoted in legal commentaries on civil and criminal proceedings of the way in which errors made in measurements for speed control and determinations of the alcohol content in the blood are to be taken into account, and a commentary on ozone legislation, are examined for analogies with radiation protection measurements. Leading cases in the nuclear field are evaluated in the light of the requirements applying in case of deviations in measurements. The final section summarizes the most important findings and conclusions. (orig.) [Deutsch] Es wird untersucht, wie aus rechtlicher Sicht Messabweichungen bei Strahlenschutzmessungen zu beruecksichtigen sind, wenn Messergebnisse mit Grenzwerten des Atomrechts oder Gueterverkehrsrechts verglichen werden. Hierzu wird eine Fallunterscheidung vorgeschlagen, die von den jeweiligen Rechtsfolgen eine Messung ausgeht. In Kommentaren zum Atomrecht konnten keine Hinweise fuer die rechtliche Bewertung von Messabweichungen bei Strahlenschutzmessungen gefunden werden. Die in Rechtskommentaren zur Zivil- und Strafprozessordnung enthaltenen Beispiele der Fehlerberuecksichtigung bei Messungen zur Geschwindigkeitsueberwachung und Blutalkoholbestimmung sowie ein Kommentar zum Ozongesetz wurden auf Analogien zu Strahlenschutzmessungen untersucht. Gerichtliche Grundsatzentscheidungen aus dem Bereich der Kerntechnik werden im Hinblick auf Anforderungen bei Messabweichungen ausgewertet. Im letzten Abschnitt sind die wichtigsten Ergebnisse und Schlussfolgerungen

  10. Measurement of radiation exposure received by flight attendants from shipments of radioactive material. Technical report

    International Nuclear Information System (INIS)

    A study was conducted in late 1974 to measure physically the radiation dose received by selected flight attendants from shipments of radioactive material transported on board commercial airline flights in the United States. This study was sponsored jointly by the two flight attendants' unions and by the U.S. Nuclear Regulatory Commission. Analyses of the data indicates that the radiation dose received by most flight attendants from these shipments is small and is well below the limit recommended for individuals of the general public by international and national organizations on radiation protection

  11. Ground-based measurements of aerosol optical properties and radiative forcing in North China

    Institute of Scientific and Technical Information of China (English)

    Hongbin Chen; Xiangao Xia; Pucai Wang; Wenxing Zhang

    2007-01-01

    In order to gain an insight into the aerosol properties and their climatic effect over the continental source regions of China, it is of significance to carry out long-term ground-based measurements of aerosol optical properties and radiative forcing. A couple of temporary and permanent Aerosol Robotic Network (AERONET) sites and three comprehensive radiative sites were established in China as a result of international cooperation in recent years. Heavy aerosol loading and significant temporal and spatial variation over North China are revealed by the AERONET data.Aerosol-induced reductions in surface radiation budget are examined on the basis of collocated observations by sun photometers and pyranometers.

  12. Imaging Thomson scattering measurements of radiatively heated Xe

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, B; Meinecke, J; Kuschel, S; Ross, J S; Divol, L; Glenzer, S H; Tynan, G R

    2012-05-01

    Uniform density and temperature Xe plasmas have been produced over >4 mm scale-lengths using x-rays generated in a cylindrical Pb cavity. The cavity is 750 {micro}m in depth and diameter, and is heated by a 300 J, 2 ns square, 1054 nm laser pulse focused to a spot size of 200 {micro}m at the cavity entrance. The plasma is characterized by simultaneous imaging Thomson scattering measurements from both the electron and ion scattering features. The electron feature measurement determines the spatial electron density and temperature profile, and using these parameters as constraints in the ion feature analysis allows an accurate determination of the charge state of the Xe ions. The Thomson scattering probe beam is 40 J, 200 ps, and 527 nm, and is focused to a 100 {micro}m spot size at the entrance of the Pb cavity. Each system has a spatial resolution of 25 {micro}m, a temporal resolution of 200 ps (as determined by the probe duration), and a spectral resolution of 2 nm for the electron feature system and 0.025 nm for the ion feature system. The experiment is performed in a Xe filled target chamber at a neutral pressure of 3-10 Torr, and the x-rays produced in the Pb ionize and heat the Xe to a charge state of 20 {+-} 4 at up to 200 eV electron temperatures.

  13. A New Measurement of the Pi0 Radiative Decay Width

    Energy Technology Data Exchange (ETDEWEB)

    Larin, I; Clinton, E; Ambrozewicz, P; Lawrence, D; Nakagawa, I; Prok, Y; Teymurazyan, A; Ahmidouch, A; Baker, K; Benton, L; Bernstein, A M; Burkert, V; Cole, P; Collins, P; Dale, D; Danagoulian, S; Davidenko, G; Demirchyan, R; Deur, A; Dolgolenko, A; Dzyubenko, Georgiy; Ent, R; Evdokimov, A; Feng, J; Gabrielyan, M; Gan, L; Gasparian, A; Gevorkyan, S; Glamazdin, A; Goryachev, V; Gyurjyan, V; Hardy, K; He, J; Ito, M; Jiang, L; Kashy, D; Khandaker, M; Kingsberry, P; Kolarkar, A; Konchatnyi, M; Korsch, W; Kowalski, S; Kubantsev, M; Kubarovsky, V; Li, X; Martel, P; Mecking, B; Milbrath, B; Minehart, R; Miskimen, R; Mochalov, V; Mtingwa, S; Overby, S; Pasyuk, E; Payen, M; Pedroni, R; Ritchie, B; Rodrigues, T E; Salgado, C; Shahinyan, A; Sitnikov, A; Sober, D; Stepanyan, S; Stephens, W; Underwood, J; Vishnyakov, V; Wood, M

    2011-04-01

    High precision measurements of the differential cross sections for $\\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^{208}$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\\pi^0 \\to \\gamma\\gamma}$ decay width. The experiment was done at Jefferson Lab using the Hall~B photon tagger and a high-resolution multichannel calorimeter. The ${\\pi^0 \\to \\gamma\\gamma}$ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is $\\Gamma{(\\pi^0 \\to \\gamma\\gamma)} = 7.82 \\pm 0.14 ~({\\rm stat.}) \\pm 0.17 ~({\\rm syst.}) ~{\\rm eV}$. With the 2.8\\% total uncertainty, this result is a factor of 2.5 more precise than the current PDG average of this fundamental quantity and it is consistent with current theoretical predictions.

  14. Improved Measurement of Inclusive Radiative B-meson decays

    CERN Document Server

    Abe, K; Brodzicka, J; Dragic, J; Fujii, H; Haba, J; Hazumi, M; Higuchi, T; Igarashi, Y; Itoh, R; Iwasaki, Y; Katayama, N; Kibayashi, A; Kichimi, H; Krokovny, P; MacNaughton, J; Nakamura, I; Nakao, M; Nishida, S; Nozaki, T; Ozaki, H; Sakai, Y; Schümann, J; Sumisawa, K; Suzuki, S Y; Tajima, O; Takasaki, F; Tamai, K; Tanaka, M; Trabelsi, K; Tsuboyama, T; Uehara, S; Uno, S; Ushiroda, Y; Aihara, M; Yamauchi H; Hastings, N C; Iwasaki, M; Kakuno, H; Kusaka, A; Nakahama, Y; Arinstein, H; Nakayama, K; Aulchenko, V; Bedny, I; Bondar, A; Eidelman, S; Epifanov, D; Gabyshev, N; Kuzmin, A; Poluektov, A; Shwartz, B; Usov, Yu; Vinokurova, A; Zhilich, V; Aziz, V; Zhulanov T; Aso, T; Aushev, T; Banerjee, S; Das, A; Gokhroo, G; Joshi, N J; Bahinipati, G; Majumdar, S; Drutskoy, A; Goldenzweig, P; Kinoshita, K; Sayeed, K; Schwartz, A J; Bakich, A; Somov, A M; Cole, S; McOnie, S; Parslow, N; Peak, L S; Varvell, K E; Balagura, B D; Yabsley, V; Chistov, R; Danilov, M; Liventsev, D; Medvedeva, T; Mizuk, R; Pakhlov, P; Pakhlova, G; Solovieva, E; Tikhomirov, I; Barberio, T; Uglov, Y; Bán, J; Wang, E; Dalseno, J; Limosani, A; Moloney, G R; Sevior, M E; Taylor, G N; Tse, Y F; Urquijo, P; Bay, R Wedd A; Hinz, L; Jacoby, C; Schietinger, T; Schneider, O; Vervink, K; Villa, S; Wicht, J; Belous, N; Zwahlen, K; Shapkin, M; Bhardwaj, A; Sokolov, V; Kumar, R; Bitenc, J B; Singh, U; Fratina, S; Pestotnik, R; Stari, M; Zupancc, J; Bozek,; Ljubljana, S; Blyth, C H; Wang, A; Kapusta, P; Lesiak, T; Matyja, A; Natkaniec, Z; Ostrowicz, W; Palka, H; Rózanska, M; Stypula, J; Wiechczynski H J; Browder, T E; Krakow, M; Brako S; Korparc, T E; Guler, H; Hoedlmoser, H; Li, J; Nishimura, K; Olsen, S L; Peters, M; Rorie, J; Sahoo, H; Uchida, K; Chang, G; Varner, M C; Chang, P; Chao, Y; Chen, K F; Chiang, C C; Hou, W S; Hsiung, Y B; Lin, S W; Shiu, J G; Ueno, K; Wang, C C; Chen, M Z; Wang, A; Chen, W T; Go, A; Hou, S; Cho, H; Nakazawa, B G; Cheon, Y; Unno, I S; Kang, J H; Choi, Y J; Kwon, S -K; Choi, Y; Choi, Y K; Kim, H O; Kim, J H; Lee, J S; Park, C W; Dash, K S; Park, M; Piilonen, L E; Fujikawa, Y; Yusa, M; Hayashii, H; Kataoka, S U; Miyabayashi, K; Noguchi, S; Sekiya, A; Garmash, D; Marlow, B; Golob, P; Krianz, M; Hara, R; Seidl, H; Ha, E; Won, K; Hayasaka, K; Hokuue, T; Iijima, T; Ikado, K; Inami, K; Kaga, M; Kaji, H; Kozakai, Y; Matsumura, T; Miyazaki, Y; Mori, T; Nishio, Y; Ohshima, T; Senyo, K; Hara, M; Heffernan, D; Yamaoka, T; Kajiwara, S; Miyake, H; Horii, S; Shinomiya, Y; Hasegawa, N; Satoyama Y; Mikami, Y; Nagamine, T; Schonmeier, P; Yamaguchi, A; Hyun, H; Yamamoto, Y; Hoshi, K; Neichi, K; Hoshina, O; Nitoh, H J; Kah, D H; Kim, H J; Ishikawa, H; Park, A; Murakami, A; Sugiyama, A; Iwabuchi, S; Suzuki, H; Ishino, S; Ono, M; Kim, Y J; Liu, Y; Sarangi, T R; Kawasaki, Y; Uchida, H; Kawai, E; Kurihara, T; Miyata, H; Tamura, N; Kim, M; Watanabe, S K; Lee, J; Lee, M J; Leder, S E; Lee, J S; Lange, G; Mandl, F; Mitaroff, W A; Pernicka, M; Schwanda, C; Nakano, L; Widhalm, J; Müller, Y; Nagasaka, E; Sakaue, H; Shang, Y; Teramoto, I; Nishizawa, T; Sumiyoshi, A; Ogawa, S; Ogawa, H; Shibuya, S; Okuno, Y; Watanabe, N; Sasao, N; Taniguchi, L; Shen, C P; Wang, P; Wang, X L; Yuan, C Z; Zhang, C C; Zhang, S; Stani, Y; Yamashita, L M; Zhang, Z P

    2008-01-01

    We report a fully inclusive measurement of the flavor changing neutral current decay $B\\to X_s\\gamma$ in the energy range $1.7 \\GeV\\le E^\\mathrm{c.m.s}_\\gamma\\le 2.8 \\GeV$, covering 97% of the total spectrum, where c.m.s is the center of mass system. Using $605\\ifb$ of data, we obtain in the rest frame of the $B$-meson ${\\mathcal B}(B\\to X_s\\gamma : E^B_\\gamma>1.7 \\mathrm{GeV})= (3.31 \\pm 0.19 \\pm 0.37 \\pm 0.01)\\times 10^{-4}$, where the errors are statistical, systematic and from the boost correction needed to transform from the rest frame of the $\\Upsilon(4S)$ (c.m.s) to that of the $B$-meson, respectively. We also measure the first and second moments of the photon energy spectrum as functions of various energy thresholds, which extend down to $1.7 \\GeV$. The results are preliminary.

  15. Calibration of modified Liulin detector for cosmic radiation measurements on-board aircraft

    Czech Academy of Sciences Publication Activity Database

    Kyselová, Dagmar; Ambrožová, Iva; Krist, Pavel; Kubančák, Ján; Uchihori, Y.; Kitamura, H.; Ploc, Ondřej

    Vol. 2015. Oxford: Oxford Journals, 2015, s. 1-4. ISSN 1742-3406. [8th International Conference on High Levels of Natural Radiation and Radon Areas (ICHLNRRA 2014). Prague (CZ), 01.09.2014-05.09.2014] R&D Projects: GA MŠk(CZ) LG13031 Institutional support: RVO:61389005 Keywords : Liulin detector * on-board aircraft * cosmic radiation measurement Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

  16. Airborne time-series measurement of soil moisture using terrestrial gamma radiation

    Science.gov (United States)

    Carroll, Thomas R.; Lipinski, Daniel M.; Peck, Eugene L.

    1988-01-01

    Terrestrial gamma radiation data and independent ground-based core soil moisture data are analyzed. They reveal the possibility of using natural terrestrial gamma radiation collected from a low-flying aircraft to make reliable real-time soil moisture measurements for the upper 20 cm of soil. The airborne data were compared to the crude ground-based soil moisture data set collected at the core sites.

  17. The impacts of optical radiation in the environment on skin: Hazards, measurement, regulation and protection

    OpenAIRE

    Oliver, Hannah Elizabeth

    2006-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. From 2001 to 2005, work was conducted at the Photobiology Unit at Ninewells Hospital in Dundee to examine the optical radiation environment and its implications for normal and diseased skin. Artificial sources of radiation were considered within the contexts of the hazards posed, measurement of the hazards, regulation concerning exposure and sources, and protection of abnormal skin from adver...

  18. Calibration technique for radiation measurements in vacuum ultraviolet - soft x-ray region

    International Nuclear Information System (INIS)

    This is a collection of the papers presented at the workshop on ''Calibration Technique for Radiation Measurements in Vacuum Ultraviolet - Soft X-ray Region'' held at the Institute of Plasma Physics, Nagoya University, on December 19 - 20, 1985, under the Collaborating Research Program at the Institute. The following topics were discussed at the workshop: the needs for the calibration of plasma diagnostic devices, present status of the calibration technique, use of the Synchrotron Orbit Radiations for radiometry, and others. (author)

  19. A fast charge digitizer and digital data acquisition system for measurement of time varying radiation fields

    International Nuclear Information System (INIS)

    An instrument capable of recording and displaying radiation waveforms is described. The instrument is used to measure ionizing radiation fields of intensities from 1 mR/min to 1000 R/min and over the range of photon energies from 20 keV to 1.2 MeV. Results obtained from testing of typical diagnostic X-ray machines are presented. (Auth.)

  20. TH-C-18A-04: Validation of Dosimetric Measurement of CT Radiation Profile Width

    International Nuclear Information System (INIS)

    Purpose: The ACR now requires that the CT radiation profile width be measured at all clinically used collimations. We developed a method for measuring the profile width using dosimetry alone to allow a faster and simpler measurement of beam widths. Methods: A pencil ionization chamber is used to take two dose-length product measurements in air for a wide collimation. One of these is taken with a 1cm tungsten mask on the pencil chamber. The difference between these measurements is the calibration factor, or the DLP in air per unit length. By dividing the doselength product for any given collimation by this factor, we can rapidly determine the beam profile width.We measured the beam width for all available detector configurations and focal spot sizes on three different CT scanners from two different manufacturers. The measurements were done using film, CR cassette, and the present dosimetric method. Results: The beam widths measured dosimetrically are approximately 2% wider than those measured using film or computed radiography; this difference is believed due to off-focus or scattered radiation. After correcting for this, the dosimetric beam widths match the film and CR widths with an RMS difference of approximately 0.2mm. The measured beam widths are largely insensitive to errors in positioning of the mask, or to tilt errors in the pencil chamber. Conclusion: Using the present method, radiation profile widths can be measured quickly, with an accuracy better than 1mm