WorldWideScience

Sample records for absolute radioactivity measurements

  1. Absolute measurement of strontium-90 and yttrium-90 radioactivity

    International Nuclear Information System (INIS)

    Strontium-90 and yttrium-90 is one of the important fission products. At present it is applied widely in industry because its half life is longer and its fission yield is higher. The radioactivity of the nuclide is concerned by human, because strontium-90 and Yttrium-90 is extremely poisonous for living things. The purpose of present work is to provide the standardization of strontium-90 and yttrium-90 radioactivity for the isotopic application and for the reprocessing plant. Method of determing strontium-90 and yttrium-90 radioactivity is efficiency trace technique while cobalt-60 nuclide is used as tracer. The total uncertainty of measurement is about ±1.4 percent

  2. Radioactivity measurements of 177Lu, 111In and 123I by different absolute methods

    International Nuclear Information System (INIS)

    The activities of 177Lu, 111In and 123I solutions have been absolutely determined using three different measurement methods. 177Lu solution was standardized using the 4??(PC)–?(NaI) coincidence and 4??(LS)–?(NaI) live-timed anticoincidence methods. For the 111In and 123I solutions, besides these two mentioned methods, the coincidence sum-peak method was also applied. The measured activities results using these different methods are consistent within the evaluated experimental uncertainties demonstrating the equivalence of these methods. As an additional contribution to nuclear data, the half-lives have been determined using a well type IG12 ionization chamber. - Highlights: ? Lu-177, I-123 and In-111 have been absolutely standardized by different methods. ? Results between methods agreed within evaluated uncertainties. ? 3-Half-lives were also measured and compared with recent published results.

  3. Absolute measurements of radio-active bodies which disintegrate after neutron capture (1962)

    International Nuclear Information System (INIS)

    The calibration of radioactive bodies which disintegrate by neutron capture is rather delicate: we describe two calibration methods which we have used. - The 4 ? X (or e) - ? coincidence method when K capture is followed by a ? disintegration; - Integral counting of all the X rays stopped in the detecting volume, for X-ray emitters of low energy disintegrating after neutron capture giving directly the fundamental level. (authors)

  4. Measurement of the absolute activity of alpha or beta emitters by measuring product nuclei (daughter) activity increase or by studing its radioactive decay

    International Nuclear Information System (INIS)

    A new method for determining absolute activity of alpha or beta emitters by measuring daughter product radioactive decay is presented. The separation method of UX from hexahydrated uranyl nitrate UO2(NO3)2 6H2O based on its dissolution in ethyl ether is described and the accuracy of this method is shown. The factors which accuate on total efficiency of a Geiger Mueller detector for beta particles are determined. The possibility to determine the mass of precursor element by daughter nuclei activity is shown. The results are compared with the one obtained by direct measurement of the mass (or number of atoms) of precursor radioactive substance and with theoretical values calculated for isotopes in secular equilibrium. (Author)

  5. An improved gas counting system for absolute activity measurement of radioactive gases

    International Nuclear Information System (INIS)

    The calibration of gas monitoring instruments with beta emitting gases is an important procedure for increasing the reliability of the measurements for radiation protection. For example, gas standards of 3 H, 85 Kr and 133 Xe are frequently used for the calibration of gas effluent monitors of the nuclear power plants. The internal gas counting with proportional counters is the most frequently method for preparing gas standards. This method is based on a complex counting system composed of two length compensated proportional detectors, a gas handling system and two spectrometric counting channels. By virtue of their different lengths, the detectors permit compensation to be done for the end effect (non-uniform detection of ionizing events caused by beta particles which takes place near to the ends of the counters). To reduce the complexity and cost of the internal gas counting system, a proportional detector was manufactured with electric field corrections at the ends for canceling the end effect. As a result, a counting system was made using only one proportional detector and only one spectrometric counting channel . (authors)

  6. Radioactive gas measuring device

    International Nuclear Information System (INIS)

    The radioactive gas measuring device comprises an introducing means for introducing radioactive gas, a sampling vessel, a measuring device for introducing and measuring radioactive gas, a gas bag for storing the radioactive gas after the measurement, an exhaustion device for exhausting the inside of the gas bag and containing the exhausted gas in a tank and a sensor for operating the exhaustion device upon reaching a predetermined value. The radioactive gas is stored in a gas bag after the measurement, and the pressure of the radioactive gas is kept stable, to improve the accuracy of the measurement. Further, when the amount of the stored radioactive gas is increased after the measurement, and the volume of the gas bag reaches a predetermined value, since the exhaustion device is operated by the sensor, the operation of the measuring device can be simplified. Then, the measurement for the radioactive gas can be conducted stably at high accuracy, thereby enabling to measure an absolute value of the impurity. The measurement for the impurity of the radioactive gas can be remarkably facilitated in the site of medical therapy. (N.H.)

  7. Measurement of the absolute \

    Energy Technology Data Exchange (ETDEWEB)

    Aunion, Jose Luis Alcaraz; /Barcelona, IFAE

    2010-07-01

    This thesis presents the measurement of the charged current quasi-elastic (CCQE) neutrino-nucleon cross section at neutrino energies around 1 GeV. This measurement has two main physical motivations. On one hand, the neutrino-nucleon interactions at few GeV is a region where existing old data are sparse and with low statistics. The current measurement populates low energy regions with higher statistics and precision than previous experiments. On the other hand, the CCQE interaction is the most useful interaction in neutrino oscillation experiments. The CCQE channel is used to measure the initial and final neutrino fluxes in order to determine the neutrino fraction that disappeared. The neutrino oscillation experiments work at low neutrino energies, so precise measurement of CCQE interactions are essential for flux measurements. The main goal of this thesis is to measure the CCQE absolute neutrino cross section from the SciBooNE data. The SciBar Booster Neutrino Experiment (SciBooNE) is a neutrino and anti-neutrino scattering off experiment. The neutrino energy spectrum works at energies around 1 GeV. SciBooNE was running from June 8th 2007 to August 18th 2008. In that period, the experiment collected a total of 2.65 x 10{sup 20} protons on target (POT). This thesis has used full data collection in neutrino mode 0.99 x 10{sup 20} POT. A CCQE selection cut has been performed, achieving around 70% pure CCQE sample. A fit method has been exclusively developed to determine the absolute CCQE cross section, presenting results in a neutrino energy range from 0.2 to 2 GeV. The results are compatible with the NEUT predictions. The SciBooNE measurement has been compared with both Carbon (MiniBoonE) and deuterium (ANL and BNL) target experiments, showing a good agreement in both cases.

  8. Absolute neutrino mass measurements

    International Nuclear Information System (INIS)

    The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2?) searches, single ?-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium ?-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope (137Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2? decay and single ?-decay.

  9. Active radiometric calorimeter for absolute calibration of radioactive sources

    International Nuclear Information System (INIS)

    This report describes the design and initial noise floor measurements of a radiometric calorimeter designed to measure therapeutic medical radioactive sources. The instrument demonstrates a noise floor of approximately 2 nW. This low noise floor is achieved by using high temperature superconducting (HTS) transition edge sensor (TES) thermometers in a temperature-control feedback loop. This feedback loop will be used to provide absolute source calibrations based upon the electrical substitution method. Other unique features of the calorimeter are (a) its ability to change sources for calibration without disrupting the vacuum of the instrument, and (b) the ability to measure the emitted power of a source in addition to the total contained source power

  10. Radioactivity and its measurement

    CERN Document Server

    Mann, W B; Garfinkel, S B

    1980-01-01

    Begins with a description of the discovery of radioactivity and the historic research of such pioneers as the Curies and Rutherford. After a discussion of the interactions of &agr;, &bgr; and &ggr; rays with matter, the energetics of the different modes of nuclear disintegration are considered in relation to the Einstein mass-energy relationship as applied to radioactive transformations. Radiation detectors and radioactivity measurements are also discussed

  11. Development of a 4? Liquid Scintillation Counting Method for the Absolute Standardization of Radioactive Solutions with Particular Reference to Efficiency Tracing Measurements

    International Nuclear Information System (INIS)

    The liquid scintillation counting method is shown to have special advantages when applied to the absolute standardization of beta emitters by the efficiency tracing technique. The simplicity of producing sources in which the active constituents are uniformly mixed, and the relative insensitivity of the method to physical and chemical effects in the sources are particularly evident. The extrapolation to 100% efficiency (zero energy) is discussed and it is shown that the normal linear extrapolation is not generally valid. The non-linearity is caused by differences in the beta spectra of the two radionuclides but the degree of non-linearity depends on the characteristics of the equipment transforming the beta spectrum into a pulse-height spectrum. For example, some events fail to produce even a single photoelectron at the photocathode and the signals from some others are lost in the noise from the photomultiplier. The number of events so lost depends on the equipment and on circumstances of the measurement, and it is not reasonable to assume that the losses will remain constant unless this can be verified experimentally. Apparatus for investigating these losses is described and its sensitivity to such effects as the non-linearity of scintillant response to beta-particle energy is discussed and shown to be small. The application of the method to routine efficiency tracing measurements is expected to lead to significant improvements in reproducibility and accuracy. (author)

  12. Measurement of radioactivity

    International Nuclear Information System (INIS)

    The measurement of environmental radioactivity in Japan started from the time of the nuclear test at Bikini in 1954, and Science and Technology Agency has established ''Measuring Procedure of Radioactivity'' in 1957. This is total beta radiation measurement, and now the revised draught including nine points to be revised has been made. Since then, analyzing procedures were established for radioactive strontium, cesium-137, radioactive iodine, and radioactive cobalt, with NaI(Tl) scintillation spectrometers, for radioactive zirconium and instrumental analysis using Ge(Li) semiconductor detectors. Presently the tritium-analyzing procedure is under discussion. As the manuals for individual analyses have been instituted, the ''general manual'' for applying those has become to be required. The problems lie not in individual procedures but in the purpose of radioactivity measurement, monitoring method, and the evaluation of data obtained. The compilation of the manual started in 1973, but now temporarily stopped because of a new problem which is the opinion insisting that manual is to include the procedures for the estimation of population exposure dose based on the data obtained. (Wakatsuki, Y.)

  13. The class of absolute decomposable inequality measures

    OpenAIRE

    Bosmans, Kristof; Cowell, Frank

    2009-01-01

    We provide a parsimonious axiomatisation of the complete class of absolute nequality indices. Our approach uses only a weak form of decomposability and does not require a priori that the measures be differentiable.

  14. Absolute cross-sections from X-? coincidence measurements

    International Nuclear Information System (INIS)

    An activation technique using coincidences between characteristic X-rays and ?-rays to obtain absolute cross-sections is described. This method is particularly useful in the case of nuclei that decay by electron capture. In addition to the reduction of possible contamination, an improved detection sensitivity is achieved as compared to inclusive measurements, thereby allowing the extraction of absolute fusion cross-sections in the nano-barn range. Results of this technique for 6Li+198Pt system, at energies around the Coulomb barrier are described. Future applications with low intensity radioactive ion beams are also discussed.

  15. Absolute radioactivity measurements of sup 1 sup 5 sup 3 Sm, sup 1 sup 8 sup 8 Re, sup 8 sup 9 Sr and national comparisons

    CERN Document Server

    Wang Jian Qing; Yao Yan Ling; Jia Xue Wen

    2003-01-01

    sup 1 sup 5 sup 3 Sm and sup 1 sup 8 sup 8 Re are short half-life nuclides and sup 8 sup 9 Sr is one of pure beta-decay nuclide, these nuclides have being applied to nuclear medicine. It's very important to carry out comparisons for radioactivity standardization of these nuclides. Several laboratories in China including our laboratory took part in the comparisons. The results from our laboratory are in good agreement with the mean values

  16. Amoeba-absoluteness and projective measurability

    CERN Document Server

    Brendle, J

    1992-01-01

    We study the relationship between Amoeba forcing (the partial order which generically adds a measure one set of random reals) and projective measurability. Given a universe V of set theory and a forcing notion P in V we say that V is Sigma^1_n - P - absolute iff for every Sigma^1_n-sentence phi with parameters in V we have V models phi iff V^P models phi. We show that Sigma^1_4-Amoeba-absoluteness implies that forall a in omega^omega (omega_1^{L[a]} < omega_1^V), and hence Sigma^1_3-measurability. This answers a question of Haim Judah (private communication).

  17. Absolute measurement of activity concentration of 87Kr by using internal gas proportional counting

    International Nuclear Information System (INIS)

    A internal gas proportional counting system for absolute measurement of gas radioactivity was established. The performances of the system, such as plateaus, back-ground, deadtime, end effect and wall effect were well tested. Then the activity concentration of 87Kr was measured absolutely to be 40.64(1 ± 0.9%) Bq/mL by this equipment. (authors)

  18. Precision absolute positional measurement of laser beams

    OpenAIRE

    Fitzsimons, E.D.; Bogenstahl, J.; Hough, J.; Killow, C.J.; Perreur-Lloyd, M; Robertson, D.I.; Ward, H.

    2013-01-01

    We describe an instrument which, coupled with a suitable coordinate measuring machine, facilitates the absolute measurement within the machine frame of the propagation direction of a millimeter-scale laser beam to an accuracy of around ±4???m in position and ±20???rad in angle.

  19. Amoeba-absoluteness and projective measurability

    OpenAIRE

    Brendle, Jörg

    1992-01-01

    We study the relationship between Amoeba forcing (the partial order which generically adds a measure one set of random reals) and projective measurability. Given a universe V of set theory and a forcing notion P in V we say that V is Sigma^1_n - P - absolute iff for every Sigma^1_n-sentence phi with parameters in V we have V models phi iff V^P models phi. We show that Sigma^1_4-Amoeba-absoluteness implies that forall a in omega^omega (omega_1^{L[a]} < omega_1^V), and hence...

  20. An absolute measure for a key currency

    Science.gov (United States)

    Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

    It is generally considered that the US dollar and the euro are the key currencies in the world and in Europe, respectively. However, there is no absolute general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an absolute measure for a key currency based on the strength of the periodicity. Moreover, we analyze the time evolution of this measure. The results show that the credibility of the US dollar has not decreased significantly since the Lehman shock, when the Lehman Brothers bankrupted and influenced the economic markets, and has increased even relatively better than that of the euro and that of the Japanese yen.

  1. Development of NANA: A Fast-Scintillator, Coincidence Gamma-ray Array for Radioactive Source Characterisation and Absolute Activity Measurements at the UK National Physical Laboratory

    Science.gov (United States)

    Regan, P. H.; Shearman, R.; Judge, S. M.; Lorusso, G.; Main, P.; Bell, S.; Collins, S. M.; Ivanov, P.; Jerome, S. M.; Keightley, J. D.; Larijani, C.; Lotay, G.; Pearce, A. K.

    2015-06-01

    A multi-detector modular coincidence gamma-ray spectrometer is being designed and constructed for use at the UK's National Physical Laboratory (NPL) for use in direct measurement and metrological standardisation of nuclear decay activities. In its first generation, the NPL National Nuclear Array (NANA) will consist of twelve individual halide scintillation detectors placed in a high-efficiency geometry around a well-defined central point source position. This brief conference paper provides details of the measured detector module and coincidence energy and timing responses for the LaBr3(Ce) detectors which will be used in the NANA array. Preliminary GEANT4 simulations of the array's full energy peak efficiency and expected gamma-ray coincidence response are also presented.

  2. Measurement of absolute gravity acceleration in Firenze

    Directory of Open Access Journals (Sweden)

    M. de Angelis

    2011-01-01

    Full Text Available This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy. In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0 ?Gal and (980 492 048.3 ± 3.0 ?Gal for the European Laboratory for Non-Linear Spectroscopy (LENS and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  3. On Absolute Measurements of ?-Emitting Radionuclides

    International Nuclear Information System (INIS)

    4 ? GM detectors are described and some of their characteristics presented. The absence of spurious pulses is shown by the measurement of the rate of arrival of intervals between pulses. Some problems related to the foil absorption and source absorption are considered using Sr90 and Y90. Aiming at correcting the counting losses in the foil and in a certain extent also the source absorption an experimental method which uses paired sources is presented. The preparation of standards of Bi210 (RaE) is described. A note is presented on the problem of foil absorption losses in scintillation absolute counting. (author)

  4. Absolute measurements of neutron induced reaction rates

    International Nuclear Information System (INIS)

    This paper describes techniques for the measurement of neutron-induced reaction rates on an absolute basis. Two main areas of application are discussed: determinations of threshold reactions used to monitor fast fluxes relevant to materials damage and neutron penetration. The accuracy required in these measurements is modest in view of other uncertainties, a standard error of +-10% normally being adequate; determinations of fission and capture rates in zero-power reactors which provide a basis for validation of data and calculation methods applied to the prediction of power reactor performance. Accuracies here are much more stringent, with +-1% on fission rates in the major heavy nuclides and +-0.7% in the capture rate in U-238 being target values based on neutron balance consid

  5. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    The low-level radioactivity measurements service performs measurements of alpha or beta emitters on various types of low-radioactivity samples (biological and environmental) from internal and external clients. to maintain and develop techniques concerning the measurement of low-level radioactivity of alpha and beta emitting radionuclides in environmental or biological samples; to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters and alpha-spectrometers); to support and advise the nuclear and non-nuclear industry on problems of radioactive contamination or low level radioactivity measurements; to maintain the quality assurance system according to the ISO17025 standard for which we obtained the Beltest accreditation in 1998; to assess the internal dose from occupational intakes of radionuclides for workers of the nuclear industry;

  6. Radioactivity measurements principles and practice

    CERN Document Server

    Mann, W B; Spernol, A

    2012-01-01

    The authors have addressed the basic need for internationally consistent standards and methods demanded by the new and increasing use of radioactive materials, radiopharmaceuticals and labelled compounds. Particular emphasis is given to the basic and practical problems that may be encountered in measuring radioactivity. The text provides information and recommendations in the areas of radiation protection, focusing on quality control and the precautions necessary for the preparation and handling of radioactive substances. New information is also presented on the applications of both traditiona

  7. Absolute number concentration measurement of submicrometer particles

    Energy Technology Data Exchange (ETDEWEB)

    Chen, T.H.B.

    1982-01-01

    Condensation nuclei in the atmosphere are known to be an important factor in the development of clouds, the occurrence of rainfall, and the formation of particulate air pollutions that can cause undesirable effects on man and his environment. Condensation nuclei are invisible and numerous, and their number concentration has become the characteristic of interest and has been widely studied since the development of the first condensation nuclei counter by Aitken in 1888. A conventional nuclei counter employs the so-called condensation technique which enables the minute nuclei to grow, in a supersaturated environment, to ..mu..m-sized droplets; the number concentration of the visible droplets is then measured. Since each nucleus grows to a droplet, the number concentration of droplets and nuclei remains the same. The number of droplets is measured by (1) direct observation with a microscope (direct counter), (2) counting from photographs of the droplets (photographic counter), (3) suitably calibrated light transmission (or scattering) measurement (relative photoelectric counter). Most of the widely-used counters are relative counters in which the instrument reading must be calibrated against a direct or photographic counter. A new condensation nuclei counter is described which is designed to have the following advantages over the widely-used counters: (a) It provides an absolute concentration measurement. (b) Even a small random fluctuation of nuclei concentration can immediately be detected.

  8. Elevation correction factor for absolute pressure measurements

    Science.gov (United States)

    Panek, Joseph W.; Sorrells, Mark R.

    1996-01-01

    With the arrival of highly accurate multi-port pressure measurement systems, conditions that previously did not affect overall system accuracy must now be scrutinized closely. Errors caused by elevation differences between pressure sensing elements and model pressure taps can be quantified and corrected. With multi-port pressure measurement systems, the sensing elements are connected to pressure taps that may be many feet away. The measurement system may be at a different elevation than the pressure taps due to laboratory space or test article constraints. This difference produces a pressure gradient that is inversely proportional to height within the interface tube. The pressure at the bottom of the tube will be higher than the pressure at the top due to the weight of the tube's column of air. Tubes with higher pressures will exhibit larger absolute errors due to the higher air density. The above effect is well documented but has generally been taken into account with large elevations only. With error analysis techniques, the loss in accuracy from elevation can be easily quantified. Correction factors can be applied to maintain the high accuracies of new pressure measurement systems.

  9. Neutronic measurements of radioactive waste

    International Nuclear Information System (INIS)

    This document presents the general matters involved in the radioactive waste management and the different non destructive assays of radioactivity. The neutronic measurements used in the characterization of waste drums containing emitters are described with more details, especially the active neutronic interrogation assays with prompt or delayed neutron detection: physical principle, signal processing and evaluation of the detection limit. (author)

  10. An All Fiber White Light Interferometric Absolute Temperature Measurement System

    OpenAIRE

    Jeonggon Harrison Kim

    2008-01-01

    Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, resp...

  11. Absolute measurement of ? activities and application to the determination of neutronic densities

    International Nuclear Information System (INIS)

    M. Berthelot, to my entrance to the ''Commissariat a l 'Energie Atomique'', proposed me to study the absolute measurement of neutron densities. Very quickly the problem of the absolute activity of ? sources became the central object of this work. In a first part, we will develop the methods of absolute determination for ? activities. The use of a 4? counter permits to get the absolute activity of all beta radioactive source, susceptible to be put as thin leaf and of period superior than some minutes. The method is independent of the spectra of the measured radioelement. we will describe in the second part some applications which use neutron densities measurement, neutron sources intensities and ratio of cross sections of capture of thermal neutrons. (M.B.)

  12. On the absolute measure of Beta activities

    International Nuclear Information System (INIS)

    A new method for absolute beta counting of solid samples is given. The mea surements is made with an inside Geiger-Muller tube of new construction. The backscattering correction when using an infinite thick mounting is discussed and results for different materials given. (Author)

  13. Low-level Radioactivity Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hurtgen, C

    2002-04-01

    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 advise the nuclear and non-nuclear industry on problems of radioactive contamination and low-level radioactivity measurements; (4) to maintain and improve the quality assurance system according to the ISO17025 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 2001 are reported.

  14. Low-level Radioactivity Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hurtgen, C

    2001-04-01

    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/ISO17025 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 2000 are reported.

  15. Measurement of the absolute luminosity with the ALEPH detector

    International Nuclear Information System (INIS)

    We report on the absolute luminosity measurement performed with the ALEPH detector at LEP. The systematic errors of the measurements in 1990 are estimated to be 0.6% (experimental) and 0.3% (theoretical). (orig.)

  16. Measurement of weak radioactivity

    CERN Document Server

    Theodorsson, P

    1996-01-01

    This book is intended for scientists engaged in the measurement of weak alpha, beta, and gamma active samples; in health physics, environmental control, nuclear geophysics, tracer work, radiocarbon dating etc. It describes the underlying principles of radiation measurement and the detectors used. It also covers the sources of background, analyzes their effect on the detector and discusses economic ways to reduce the background. The most important types of low-level counting systems and the measurement of some of the more important radioisotopes are described here. In cases where more than one

  17. Statistical aspects in radioactivity measurements

    International Nuclear Information System (INIS)

    This report contains a summary of basic concepts and formulae important for the treatment of errors and for calculating lower limits of detection in radioactivity measurements. Special attention has been paid to practical application and examples which are of interest for scientists working in this field. (orig./HP)

  18. An All Fiber White Light Interferometric Absolute Temperature Measurement System

    Science.gov (United States)

    Kim, Jeonggon Harrison

    2008-01-01

    Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.

  19. An All Fiber White Light Interferometric Absolute Temperature Measurement System

    Directory of Open Access Journals (Sweden)

    Jeonggon Harrison Kim

    2008-11-01

    Full Text Available Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.

  20. Environmental radioactivity intercomparison measurements

    International Nuclear Information System (INIS)

    In the context of the North Cotentin radioecological group set up in 1997 by the Ministry of the Environment and the Ministry of the Secretariat d'Etat a la Sante, the Swiss Federal Office of Public health, a national organization of independent status with respect to nuclear energy, conducted a series of measurements in the north Cotentin in 1998. Some sites proposed by local association 'Angry mothers' were examined in particular. This association has now taken the initiative to organize a large scale international intercomparison, ' North Cotentin 2000', in the vicinity of local nuclear installations. Besides the scientific aspect of the intercomparison, a specific aim of this intercomparison consists in providing to the local population with a real opportunity for direct exchange with participating international teams. The primary concern of the workshop is the determination, by in situ gamma spectrometry, of both natural and artificial concentrations and resulting ambient dose rates at selected marine ( beach) and terrestrial sites. A particular aim of the workshop also is to test the capacity of mobile teams to produce reliable results in the field of low level measurements on trace of special radionuclides (I129, Sr90, H3, C14, and alpha emitters) from environmental samples, using both direct ( in situ) and differed ( laboratory methods). an overview of the results obtained will be prepared for the benefit of the public. (N.C.)

  1. Accuracy of absolute gravity measurements when measuring crustal deformation

    Science.gov (United States)

    van Camp, M.; Williams, S. D.; Francis, O.; Camelbeeck, T.

    2004-12-01

    To observe secular land movements of the order of a few millimetres per year, a very precise instrument with long-term stability is required. This can be achieved using absolute gravimeters, which do not depend on a reference frame. Vertical land movements would modify the gravity at a rate of about -10 nms-2 (1 ? Gal) for 5 mm of uplift. Repeated absolute gravity (AG) measurements have now been performed at several sites for five or more years to constrain, for example, tectonic deformation and post-glacial rebound. It is often assumed that these time series contain only white noise. However, many geodetic data sets have now provided evidence for error sources that introduce large temporal correlations into the data. One common statistical model for many types of geophysical signal (which may contribute to the noise) maybe described as a power-law process. Accounting for the type of noise is very important when estimating gravity variations and their uncertainties. Moreover this can contribute to identify the noise source(s) affecting AG measurements We present an analysis of the error model using 10 years of AG data taken at the Proudman Oceanographic Laboratory (POL) and using 96 AG gravity measurements recorded over a period of 8 years at the Membach station (Belgium). A superconducting gravimeter (SG) is also continuously monitoring gravity variations at this site. The AG set-up white noise is estimated by comparison with the SG series. The coloured environmental noise is estimated using the Maximum Likelihood Estimation (MLE) technique to fit two types of stochastic model to the SG time series, power-law noise and first order Gauss Markov (FOGM) noise. The gravity rate of change and the associated uncertainties as a function of the noise structure are computed. Then we investigate the noise of AG values at frequencies higher than 1 cpd, where a white noise component usually dominates. Finally the POL and Membach experiments are applied to estimate the uncertainties of AG campaigns repeated once or twice a year to monitor crustal deformation. The results from repeated AG campaigns along a profile across the Ardenne and along the UK coastline are presented. Such repeated AG measurements should allow one to constrain gravity rate of change with an uncertainty of 1 nms-2 (or 0.5 mm) after 8 to 15 years. The conclusion is that long-term measurements using absolute gravimeters are appropriate for monitoring slow vertical tectonic deformation.

  2. Estimation of absolute error of measuring rock volume density

    International Nuclear Information System (INIS)

    Absolute error of measuring rock volume density in wells by gamma-gamma logging is estimated using computer calculations. The results of calculations have shown that the application of equipment for compensated gamma-gamma density logging (e.g. the RKS-1 radiometer) provides the measurement of rock volume density of an arbitrary mineral composition in the range of 2-2.8 g/cm3 with the absolute error not more than 0.05 g/cm3

  3. Absolute Branching Fraction Measurements of Exclusive D^0 Semileptonic Decays

    OpenAIRE

    Coan, T. E.

    2005-01-01

    With the first data sample collected by the CLEO-c detector at the psi(3770) resonance we have studied four exclusive semileptonic decays of the D0 meson. Our results include the first observation and absolute branching fraction measurement for D0 --> rho- e+ nu_e and improved measurements of the absolute branching fractions for D0 decays to K- e+ nu_e, pi- e+ nu_e, and K*- e+ nu_e.

  4. Radioactivity measurements and control solutions

    International Nuclear Information System (INIS)

    In our department, in the last years, a new line of production has been developed devoted to the radioactivity measurements (portal monitor, gamma source detector, neutron monitor). Instruments of different design (hand-held, portals or steady-state) are intended for detection and locating of radioactive sources. Monitors are intended to detect radioactive and special nuclear materials in vehicles, pedestrians, luggage, as well as for illegal traffic prevention of radioactive sources. Monitors provide audio and visual alarm signals when radioactive and/or special nuclear materials are detected. Neutron dosimeters are designed for the determination of dose equivalent rate around neutron generators or sources. All devices can be recommended for use to officers of customs, border guard and emergency services, civil defense, fire brigades, police and military departments, nuclear research or power facilities. Incorporating micro controllers and new design, our products span almost all the spectra of radioactivity detection (gamma, beta, X and neutrons). No special knowledge is needed to operate these instruments as all service functions are performed automatically (self-tests, background updating and threshold calculation). The Portal monitor is intended to be a checkpoint in contamination control or in unauthorized traffic of radioactive materials. The portal monitor can be installed both in open, unprotected to environmental conditions areas or in enclosed areas. It may be used at pedestrian cross border points, at check points of Nuclear Power Plants, enterprises of nuclear industry, weapons manufacturing and storage plants, nuclear waste disposal and storage sites, at the entrances to steel plants, the post-offices and airports, the governmental offices, banks, private companies etc. The monitor provides audio alarming signals when radioactive and/or special nuclear materials are detected. The monitor consists in a portal frame, which sustains 5 detectors. Each detector is an assembly consisting in a plastic scintillator, a photomultiplier and the associated electronics, all these components being mounted inside an aluminum cylindrical case. The specifications are: - Detects at least 1 Ci radioactivity spread all over the inspected body in a 20 Roentgen/h overall background; - Maximum detectable radioactivity, 10 Ci; - Acquisition time between 1 to 10 seconds. The Neutron Monitor is derived from the Bonner Spectrometer. The Bonner Spectrometer description is quite simple: A proportional counter filled with Helium 3 at a pressure value between 2 and 6 atmospheres is the detecting element. It is coated with a thick layer of hydrogen-rich material such as polyethylene. The output signal is measured by the current in the counter wire when it is biased to about +1000 volts. Our Neutron Monitor is a portable, battery powered monitor for dose equivalent rate measurements around reactors, accelerators and other neutron generating installations or sources. The instrument measures the neutron dose equivalent rate in units of Sv/h. It is important to note that we need to know the neutron energies to be measured so that the appropriate energy response correction factors are coded into the instrument driving calibrations. If these a priori data is not available the Neutron Monitor can only offer plain counts/second. The appropriate diameter for the polyethylene sphere was chosen to be 5 inches (127 mm). The instrument is equipped with a microprocessor and a 2 x 16 character display unit along with two push buttons. This simple setup configuration permits to choose the acquisition time base and the display mode (counts or Sv). Its specifications are: - Dose rate range,1 Sv/h to 100 mSv/h (neutron spectrum information is required before calibration); - Energy response, thermal range to 14 MeV; - Detector, He-3 proportional counter surrounded by 127 mm polyethylene sphere (SP9). The portable gamma source sniffer consists of a NaI(Tl) crystal, a photomultiplier and the associated electronics, all contained in an aluminum cylindrical case

  5. Measurement of radioactivity in Norway

    International Nuclear Information System (INIS)

    A nation-wide network of 11 monotoring stations for continuous registration of radioactivity in the air has been established in Norway. Via the telecommunication network, collected data are dayly automatically transmitted to the Norwegian Institute for Air Research (NILU). High radiation levels trigger an alarn for immediate transmission. The monotoring system and experiences in connection with its operation are described, and results from measurements in 1988 are presented. 14 figs

  6. Absolute measurement methods for reflectance and fluorescence

    OpenAIRE

    Holopainen, Silja

    2009-01-01

    Reflectance and fluorescence are important properties when determining the colour and appearance of solid opaque material. They are also useful in several other industrial applications such as those in biochemical and medical industry and in remote sensing. In most industrial applications, the reflectance and / or fluorescence characteristics of samples are measured relative to a known reference standard. The uncertainty of the measurements is naturally dependent on the uncertainty of the ref...

  7. The absolute measurement and analysis of 198Au activation

    International Nuclear Information System (INIS)

    198Au has a series of merits, such as the simple disintegration Chart, the single isotope constitute, the clear activation section, the high purity and the easy machining. Therefore, 198Au is used the first choice for the neutron flux absolute measurement. The activations absolute measurement for a set of 198Au samples which have been activated in reactor is finished through a suit of new type 4??-? coincidence measurement device which is designed by ourselves in lab. By compare, these measurement values and theory values accord in range of uncertainty, the most uncertainty is less than 1.2%. We can draw a conclusion that the activation absolute measurement of this set of 198Au samples is reliable. (authors)

  8. On the Absolute Continuity of the Blackwell Measure

    Science.gov (United States)

    Bárány, Balázs; Kolossváry, István

    2015-04-01

    In 1957, Blackwell expressed the entropy of hidden Markov chains using a measure which can be characterised as an invariant measure for an iterated function system with place-dependent weights. This measure, called the Blackwell measure, plays a central role in understanding the entropy rate and other important characteristics of fundamental models in information theory. We show that for a suitable set of parameter values the Blackwell measure is absolutely continuous for almost every parameter in the case of binary symmetric channels.

  9. MEASUREMENTS OF ABSOLUTE ABUNDANCES IN SOLAR FLARES

    International Nuclear Information System (INIS)

    We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory. EVE observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (f). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature, it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is f = 1.17 ± 0.22. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation occurs

  10. MEASUREMENTS OF ABSOLUTE ABUNDANCES IN SOLAR FLARES

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

    2014-05-01

    We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory. EVE observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (f). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature, it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is f = 1.17 ± 0.22. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation occurs.

  11. Effects of natural radioactivity on food radioactivity measurement

    International Nuclear Information System (INIS)

    Since the accident of the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Company, groups and individuals including local governments, food manufacturers, distribution circles, retail circles, and citizens are eager to measure the radioactivity of food, in order to confirm the safety of food from the concerns about radioactive contamination. The measurement of radioactivity of food is done by quantitatively determining gamma rays due to radioactive cesium that was incorporated into the biosphere cycle after having been released into the environment. As for the radioactivity measurement of food using gamma-ray spectrometry with a potassium iodide scintillation detector, which is very commonly used, this paper describes the handling method of obtained data, the principle of erroneous detection of radioactive cesium and iodine interrupted by natural radionuclides, and countermeasures for it. Major natural radioactivity sources are uranium series and thorium series. This paper explains gamma rays, which are characteristic in the decay process of uranium series and often affect the measurement of radioactive cesium in food and water. (O.A.)

  12. Mathematical Model for Absolute Magnetic Measuring Systems in Industrial Applications

    Science.gov (United States)

    Fügenschuh, Armin; Fügenschuh, Marzena; Ludszuweit, Marina; Mojsic, Aleksandar; Sokó?, Joanna

    2015-09-01

    Scales for measuring systems are either based on incremental or absolute measuring methods. Incremental scales need to initialize a measurement cycle at a reference point. From there, the position is computed by counting increments of a periodic graduation. Absolute methods do not need reference points, since the position can be read directly from the scale. The positions on the complete scales are encoded using two incremental tracks with different graduation. We present a new method for absolute measuring using only one track for position encoding up to micrometre range. Instead of the common perpendicular magnetic areas, we use a pattern of trapezoidal magnetic areas, to store more complex information. For positioning, we use the magnetic field where every position is characterized by a set of values measured by a hall sensor array. We implement a method for reconstruction of absolute positions from the set of unique measured values. We compare two patterns with respect to uniqueness, accuracy, stability and robustness of positioning. We discuss how stability and robustness are influenced by different errors during the measurement in real applications and how those errors can be compensated.

  13. Absolute Branching Fraction Measurements of Exclusive D^+ Semileptonic Decays

    OpenAIRE

    G. S. Huang

    2005-01-01

    Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present improved measurements of the absolute branching fractions of D+ decays to K0B e+ nu_e, pi0 e+ nu_e, K0B* e+ nu_e, and rho0 e+ nu_e, and the first observation and absolute branching fraction measurement of D+ --> omega e+ nu_e. We also report the most precise tests to date of isospin invariance in semileptonic D0 and D+ decays.

  14. Influence of diffraction effect on measurements of absolute gravity

    Science.gov (United States)

    Su, Duowu; Li, Chunjian; Wu, Shuqing; Feng, Jinyang; Xu, Jinyi

    2015-02-01

    By raising measurement accuracy of absolute gravimeter, we need to find out the influence factor and conduct evaluation. After the 8th international key comparison of absolute gravimeter in 2009(ICAG-2009), people emphasize putting forward some correction key point, one of them is the diffraction correction. Due to divergence of laser beam, wave front is arc-shaped, laser beam of interferometer cannot go all the way with falling body's drop direction. Because of this reason, the measurement result is less than original value. This is called diffraction effect. Here, this correction is called "Diffraction Correction". For our absolute gravimeter NIM-3A, we research this effect and bring forward evaluation method and correction value. In this paper, we will conduct research and calculate. Consequently, we could receive the correction value of acceleration of gravity.

  15. Heat amount measuring method for radioactive waste

    International Nuclear Information System (INIS)

    The present invention provides a device for easily and accurately measuring the amount of heat generated from high level radioactive wastes generated upon reprocessing of spent fuels. Namely, radioactive wastes are contained in a measuring vessel formed by using thick-walled iron plates. Air is circulated in the measuring vessel. The temperatures of charged air and discharged air are measured. Then the amount of heat dissipated from the radioactive wastes and the amount of heat dissipated from the iron plates due to absorption of ?-rays to the iron plates are obtained based on the temperature difference. Accordingly, the amount of heat generated from the radioactive wastes can be measured accurately. In addition, there is provided an effect that the amount of heat generated from radioactive wastes can be measured by simple procedures of charging radioactive wastes in the measuring vessel and driving air circulation fans. (I.S.)

  16. Europe's Other Poverty Measures: Absolute Thresholds Underlying Social Assistance

    Science.gov (United States)

    Bavier, Richard

    2009-01-01

    The first thing many learn about international poverty measurement is that European nations apply a "relative" poverty threshold and that they also do a better job of reducing poverty. Unlike the European model, the "absolute" U.S. poverty threshold does not increase in real value when the nation's standard of living rises, even though it is…

  17. Absolute luminosity measurements with the LHCb detector at the LHC

    CERN Document Server

    Aaij, R; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Brisbane, S; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Caicedo Carvajal, J M; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Constantin, F; Conti, G; Contu, A; Cook, A; Coombes, M; Corti, G; Cowan, G A; Currie, R; D'Almagne, B; D'Ambrosio, C; David, P; De Bonis, I; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Deissenroth, M; Del Buono, L; Deplano, C; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Eames, C; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; d'Enterria, D G; Esperante Pereira, D; Estève, L; Falabella, A; Fanchini, E; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hofmann, W; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koblitz, S; Koppenburg, P; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kukulak, S; Kumar, R; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Luisier, J; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinez Santos, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Mclean, C; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M-N; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nardulli, J; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen-Mau, C; Nicol, M; Nies, S; Niess, V; Nikitin, N; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B; Palacios, J; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Paterson, S K; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C

    2012-01-01

    Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overall precision of 3.5\\% in the absolute lumi...

  18. Measurement of radioactivity in water samples

    International Nuclear Information System (INIS)

    Public concern about the levels of radioactivity release to the environment whether authorised discharges or resulting from nuclear accident, has increased in recent years. Consequently there is increasing pressure for reliable data on the distribution of radioactivity and the extent of its intrusion into food chains and water supplies. As a result a number of laboratories not experienced in radioactivity measurements have acquired nucleonic counting equipment. These notes explore the underlying basics and indicate sources of essential data and information which are required for a better understanding of radioactivity measurements. Particular attention is directed to the screening tests which are usually designated ''gross'' alpha and ''gross'' beta activity measurement. (author)

  19. Absolute gravity acceleration measurement in atomic sensor laboratories

    Science.gov (United States)

    de Angelis, M.; Greco, F.; Pistorio, A.; Poli, N.; Prevedelli, M.; Saccorotti, G.; Sorrentino, F.; Tino, G. M.

    2012-03-01

    This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the Florence University (Italy). In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the measurement of forces with high spatial resolution are in progress. Both experiments require an independent knowledge on the local value of g. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are ( 980 492 160.6 ± 4.0) ?Gal and ( 980 492 048.3 ± 3.0) ?Gal for the European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  20. Absolute measurement of square flats with Legendre polynomial fitting method

    Science.gov (United States)

    Gao, Bo; Li, Qiang; He, Yuhang; Chai, Liqun; Wei, Xiaohong

    2014-12-01

    Zernike Polynomial fitting method is an effective way to reconstruct absolute surface for three-flat test. However, the Zernike circle polynomials are not orthogonal over the circular area, hence they are not suitable for square flat. We present an absolute testing of a square flat with Legendre polynomial fitting method, which relies on calculating the coefficients of the Legendre terms by least-square fitting method. To obtain the three-dimensional surface data, one additional measurement that rotate the test flat through 90° should be introduced. The formulas are derived theoretically in detail, and validity has been proved by simulated experiment. Vertical profiles of the three surfaces are compared with the measurement results obtained by three-flat test. Good agreement validates our method.

  1. Measurement of the absolute branching fraction of the Ds+- meson

    CERN Document Server

    Abe, K; Dragic, J; Fujii, H; Gershon, T; Haba, J; Hazumi, M; Higuchi, T; Igarashi, Y; Itoh, R; Iwasaki, Y; Katayama, N; Kichimi, H; Krokovnyi, P P; Limosani, A; Nakamura, I; Nakao, M; Nakazawa, H; Nishida, S; Nozaki, T; Ozaki, H; Ronga, F J; Saitoh, S; Sakai, Y; Stamen, R; Sumisawa, K; Suzuki, S Y; Tajima, O; Takasaki, F; Tamai, K; Tanaka, M; Trabelsi, K; Tsuboyama, T; Tsukamoto, T; Uehara, S; Unno, Y; Uno, S; Ushiroda, Y; Yamauchi, M; Zhang, J; Hoshi, Y; Neichi, K; Aihara, H; Hastings, N C; Ishikawa, A; Itoh, K; Iwasaki, M; Kakuno, H; Kusaka, A; Nakahama, Y; Tanabe, K; Anipko, D; Arinstein, K; Aulchenko, V; Bedny, I; Bondar, A; Eidelman, S; Epifanov, D A; Gabyshev, N; Kuzmin, A; Poluektov, A; Root, N; Shwartz, B; Sidorov, V; Usov, Yu; Zhilich, V; Aoki, K; Enari, Y; Hara, K; Hayasaka, K; Hokuue, T; Iijima, T; Ikado, K; Inami, K; Kishimoto, N; Kozakai, Y; Kubota, T; Miyazaki, Y; Ohshima, T; Okabe, T; Sato, N; Senyo, K; Yoshino, S; Arakawa, T; Kawasaki, T; Miyata, H; Tamura, N; Watanabe, M; Asano, Y; Aso, T; Aushev, T; Bay, A; Hinz, L; Jacoby, C; Schietinger, T; Schneider, O; Villa, S; Wicht, J; Zürcher, D; Aziz, T; Banerjee, S; Gokhroo, G; Majumder, G; Bahinipati, S; Drutskoy, A; Goldenzweig, P; Kinoshita, K; Kulasiri, R; Sayeed, K; Schwartz, A J; Somov, A; Bakich, A M; Cole, S; McOnie, S; Parslow, N; Peak, L S; Stöck, H; Varvell, K E; Yabsley, B D; Balagura, V; Chistov, R; Danilov, M; Liventsev, D; Medvedeva, T; Mizuk, R; Pakhlov, P; Pakhlova, G; Tikhomirov, I; Uglov, T; Tian, Y BanX C; Barberio, E; Dalseno, J; Dowd, R; Moloney, G R; Sevior, M E; Taylor, G N; Tse, Y F; Urquijo, P; Barbero, M; Browder, T E; Guler, H; Jones, M; Li, J; Nishimura, K; Olsen, S L; Peters, M; Rorie, J; Sahoo, H; Uchida, K; Varner, G; Belous, K S; Shapkin, M; Sokolov, A; Bitenc, U; Bizjak, I; Fratina, S; Gorisek, A; Pestotnik, R; Staric, M; Zupanc, A; Blyth, S; Chen, A; Chen, W T; Go, A; Hou, S; Kuo, C C; Bozek, A; Kapusta, P; Lesiak, T; Matyja, A; Natkaniec, Z; Ostrowicz, W; Palka, H; Rózanska, M; Wiechczynski, J; Bracko, M; Korpar S; Brodzicka, J; Chang, M C; Kikuchi, N; Mikami, Y; Nagamine, T; Schonmeier, P; Yamaguchi, A; Yamamoto, H; Chang, P; Chao, Y; Chen, K F; Hou, W S; Hsiung, Y B; Lee, Y J; Lin, C Y; Lin, S W; Shen, Y T; Tsai, Y T; Ueno, K; Wang, C C; Wang, M Z; Wu, C H; Cheon, B G; Choi, J H; Ha, H; Kang, J S; Won, E; Choi, S K; Choi, Y; Choi, Y K; Kim, H O; Kim, J H; Park, C W; Park, K S; Chuvikov, A; Garmash, A; Marlow, D; Ziegler, T; Dash, M; Mohapatra, D; Piilonen, L E; Yusa, Y; Fujikawa, M; Hayashii, H; Imoto, A; Kataoka, S U; Miyabayashi, K; Noguchi, S; Krizan, P; Golob, B; Seidl, R; Grosse-Perdekamp, M; Hara, T; Heffernan, D; Miyake, H; Hasegawa, Y; Satoyama, N; Takada, N; Nitoh, O; Hoshina, K; Ishino, H; Khan, H R; Kibayashi, A; Mori, T; Ono, S; Watanabe, Y; Iwabuchi, M; Kim, Y J; Liu, Y; Sarangi, T R; Uchida, Y; Kang, J H; Kim, T H; Kwon, Y J; Kurihara, E; Kawai, H; Park, H; Kim, H J; Kim, S K; Lee, J; Lee, S E; Yang He Young; Kumar, R; Singh, J B; Soni, N; Lange, J S; Leder, G; MacNaughton, J; Mandl, F; Mitaroff, W A; Pernicka, M; Schwanda, C; Widhalm, L; Matsumoto, T; Nakagawa, T; Seki, T; Sumiyoshi, T; Yamamoto, S; Müller, J; Murakami, A; Sugiyama, A; Suzuki, S; Nagasaka, Y; Nakano, E; Sakaue, H; Teramoto, Y; Ogawa, A; Shibuya, H; Ogawa, S; Okuno, S; Sakamoto, H; Wang, C H; Schümann, J; Stanic, S; Xie, Q L; Yuan, Y; Zang, S L; Zhang, C C; Yamashita, Y; Zhang, L M; Zhang, Z P

    2006-01-01

    The Ds+- -> K+-K-+pi+- absolute branching fraction is measured using e+e- -> Ds*+- Ds1-+(2536) events collected by the Belle detector at the KEKB e+e- asymmetric energy collider. Using the ratio of yields when either the Ds1 or Ds* is fully reconstructed, we find Br(Ds+- -> K+-K-+pi+-)= (4.0+-0.4(stat)+-0.4(sys))%.

  2. 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.

  3. Absolute bunch length measurements by incoherent radiation fluctuation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sannibale, Fernando; Stupakov, Gennady; Zolotorev, Max; Filippetto, Daniele; Jagerhofer, Lukas

    2008-09-29

    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.

  4. Absolute and Relative Deprivation and the Measurement of Poverty

    OpenAIRE

    Duclos, Jean-Yves; Gregoire, Philippe

    2001-01-01

    This paper develops the link between poverty and inequality by focussing on a class of poverty indices (some of them well-known) which aggregate normative concerns for absolute and relative deprivation. The indices are distinguished by a parameter that captures the ethical sensitivity of poverty measurement to "exclusion" or "relative-deprivation" aversion. We also show how the indices can be readily used to predict the impact of growth on poverty. An illustration using LIS data finds that he...

  5. Absolute and relative deprivation and the measurement of poverty

    OpenAIRE

    Duclos, Jean-Yves

    2006-01-01

    This paper develops the link between poverty and inequality by focussing on a class of poverty indices (some of them well-known) which aggregate normative concerns for absolute and relative deprivation. The indices are distinguished by a parameter that captures the ethical sensitivity of poverty measurement to ``exclusion'' or ``relative-deprivation'' aversion. We also show how the indices can be readily used to predict the impact of growth on poverty. An illustration using LIS data finds tha...

  6. Precision Absolute Beam Current Measurement of Low Power Electron Beam

    Energy Technology Data Exchange (ETDEWEB)

    Ali, M. M.; Bevins, M. E.; Degtiarenko, P.; Freyberger, A.; Krafft, G. A.

    2012-11-01

    Precise measurements of low power CW electron beam current for the Jefferson Lab Nuclear Physics program have been performed using a Tungsten calorimeter. This paper describes the rationale for the choice of the calorimeter technique, as well as the design and calibration of the device. The calorimeter is in use presently to provide a 1% absolute current measurement of CW electron beam with 50 to 500 nA of average beam current and 1-3 GeV beam energy. Results from these recent measurements will also be presented.

  7. A quantitative PCR method for measuring absolute telomere length

    OpenAIRE

    Fenech Michael; O'Callaghan Nathan J

    2011-01-01

    Abstract We describe a simple and reproducible method to measure absolute telomere length (aTL) using quantitative real-time polymerase chain reaction (qPCR). This method is based on the Cawthon method for relative measurement of telomere length (TL) but modified by introducing an oligomer standard to measure aTL. The method describes the oligomer standards, the generation of the standard curve and the calculations required to calculate aTL from the qPCR data. The necessary controls and perfo...

  8. Precision Absolute Beam Current Measurement of Low Power Electron Beam

    International Nuclear Information System (INIS)

    Precise measurements of low power CW electron beam current for the Jefferson Lab Nuclear Physics program have been performed using a Tungsten calorimeter. This paper describes the rationale for the choice of the calorimeter technique, as well as the design and calibration of the device. The calorimeter is in use presently to provide a 1% absolute current measurement of CW electron beam with 50 to 500 nA of average beam current and 1-3 GeV beam energy. Results from these recent measurements will also be presented

  9. Absolute measurements of photoionization cross-sections for ions

    International Nuclear Information System (INIS)

    A merged-beam set-up for absolute measurements of photoionization cross-sections of ions is described. The facility is capable of recording cross-sections as low as 10-19 cm2 and has been used to study a large number of singly- and multiply-charged, atomic and molecular, positive and negative ions. It is based on a synchrotron radiation beam line fitted with an undulator at the storage ring ASTRID and a low-energy (?2 keV) ion beam line. Photons in the energy range 15-200 eV are merged co-linearly with the target ions over a distance of 50 cm, and the absolute photoionization cross-section is determined from the resulting photoion yield with a typical accuracy of 10%. Different types of ion sources are available, thus permitting a large number of positive and negative, atomic and molecular, singly- and multiply-charged ions to be investigated. Emphasis is put on accurate determination of the absolute cross-sections, requiring calibration of photodiode and particle detectors together with measurements of the photon-ion overlap

  10. Absolute fluence measurement for a prototype neutron radiotherapy source

    International Nuclear Information System (INIS)

    An inexpensive recoil-proton counter telescope has been designed for absolute fluence measurements of a gas-target neutron source for radiation therapy. The detector has an absolute efficiency of 1.1times10-9 at 20 cm from an isotropic source and is useful for production rates of 109--1013 neutrons per second. The telescope consists of a thin hydrogenous irradiator foil and a surface-barrier detector to count recoil protons within a defined solid angle. The telescope provides n-? discrimination as well as discrimination against scattered neutrons. Initial tests of the counter telescope were performed using the DD reaction employed in development stages of the gas target. A clear separation of full-energy recoil protons from background and scattered neutron events was evident in the pulse-height spectra without the use of coincidence gating techniques

  11. Absolute measurements of chlorine Cl+ cation single photoionization cross section

    International Nuclear Information System (INIS)

    The photoionization of Cl+ leading to Cl2+ was measured in the photon energy range of 19.5–28.0 eV. A spectrum with a photon energy resolution of 15 meV normalized to absolute cross-section measurements is presented. The measurements were carried out by merging a Cl+ ion beam with a photon beam of highly monochromatic synchrotron radiation at the Advanced Light Source at Lawrence Berkeley National Laboratory. The measured photoionization of Cl+ consists of several autoionization resonances surperimposed on the direct photoionization signal. Most of the prominent resonances are assigned to members of Rydberg series originating from the singlet ground state and from metastable triplet levels within the ground-state configuration of Cl+. The direct ionization cross section is no larger than 12 Mb. - Highlights: • The single photoionization absolute cross section of Cl+ ion was measured. • Numerous resonances were identified as belonging to Rydberg series. • A large population of the metastable Cl+(1D2) was identified. • Identified resulting Cl2+ state terms correspond to 2D5/2 and 2D3/2

  12. Absolute and specific measures of research group excellence

    CERN Document Server

    Mryglod, O; Holovatch, Yu; Berche, B

    2012-01-01

    A desirable goal of scientific management is to introduce, if it exists, a simple and reliable way to measure the scientific excellence of publicly-funded research institutions and universities to serve as a basis for their ranking and financing. While citation-based indicators and metrics are easily accessible, they are far from being universally accepted as way to automate or inform evaluation processes or to replace evaluations based on peer review. Here we consider absolute measurements of research excellence at an amalgamated, institutional level and specific measures of research excellence as performance per head. Using biology research institutions in the UK as a test case, we examine the correlations between peer-review-based and citation-based measures of research excellence on these two scales. We find that citation-based indicators are very highly correlated with peer-evaluated measures of group strength but are poorly correlated with group quality. Thus, and almost paradoxically, our analysis indi...

  13. An absolute scale for measuring the utility of money

    Science.gov (United States)

    Thomas, P. J.

    2010-07-01

    Measurement of the utility of money is essential in the insurance industry, for prioritising public spending schemes and for the evaluation of decisions on protection systems in high-hazard industries. Up to this time, however, there has been no universally agreed measure for the utility of money, with many utility functions being in common use. In this paper, we shall derive a single family of utility functions, which have risk-aversion as the only free parameter. The fact that they return a utility of zero at their low, reference datum, either the utility of no money or of one unit of money, irrespective of the value of risk-aversion used, qualifies them to be regarded as absolute scales for the utility of money. Evidence of validation for the concept will be offered based on inferential measurements of risk-aversion, using diverse measurement data.

  14. Recent advances in absolute distance measurements using femtosecond light pulses

    Science.gov (United States)

    Kim, Seung-Woo; Kim, Young-Jin; Hyun, Sangwon; Chun, Byung Jae; Jang, Yoon-Soo

    2015-02-01

    Absolute distance measurement (ADM) with high precision is required for various fields of precision engineering, which has long been implemented by means of time-of-flight measurement of a pulsed laser, intensity or frequency modulation of a continuous-wave laser, and cross-correlation of pseudo-random micro-wave signals. Recently, in response to increasing demands on the measurement precision and range beyond conventional limits, femtosecond pulse lasers began to draw attention as a new light source that permits realizing various advanced ADM principles such as synthetic radiofrequency wavelength generation, Fourier-transform-based dispersive analysis and multi-wavelength interferometry. In this talk, we present the state-of-the-art measurement principles and performance demonstrated by exploiting the unique temporal and spectral characteristics of femtosecond laser pulses for high-precision ADM applications.

  15. Absolute measurement of hadronic branching fractions of the Ds+ meson.

    Science.gov (United States)

    Alexander, J P; Berkelman, K; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; Lopez, A; Mendez, H; Ramirez, J; Ge, J Y; Miller, D H; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Rademacker, J; Asner, D M; Edwards, K W; Naik, P; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L

    2008-04-25

    The branching fractions of D(s)(+/-) meson decays serve to normalize many measurements of processes involving charm quarks. Using 298 pb(-1) of e(+)e(-) collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for eight D(s)(+/-) decays with a double tag technique. In particular we determine the branching fraction B(D(s)(+)-->K(-)K(+}pi(+))=(5.50+/-0.23+/-0.16)%, where the uncertainties are statistical and systematic, respectively. We also provide partial branching fractions for kinematic subsets of the K(-)K(+)pi(+) decay mode. PMID:18518186

  16. High-precision absolute measurement of CEBAF beam mean energy

    International Nuclear Information System (INIS)

    The absolute measurement of the beam mean energy with an accuracy of one part in 104 or higher is an important demand of the CEBAF Hall A physics program. This accuracy may reduce the uncertainty in the d(e, e'p)p cross section ??/? to 1%. The need for such an accurately calibrated beam is not particular to CEBAF; at other electron facilities uncertainty in the incident energy has proven to be among the dominant sources of systematic error. The following methods for solving the problem were considered at both CEBAF and the Yerevan Physics Institute during 1990--1991: Backscattering of a plane electromagnetic wave by the relativistic electron beam. Calculations show that the intensity of the backscattered radiation in a bandwidth of 10-4 near the maximum frequency is about 1 photon per second at 4 GeV and 0.3 mA. Magnetic spectrometers performing as three- and four-magnet chicanes with appropriate detector systems. Such a system was used at SLAC for absolute measurement of the SLC beams energy, where a maximum accuracy of 5 x 10-4 was achieved. Calculations show that a similar accuracy can be achieved for the CEBAF beam in both proposed systems. Measurement of the vertical distribution of synchrotron radiation. Calculations indicate that precision of about 2.5 x 10-5 is achievable for CEBAF

  17. Model YZ-1 radioactive contamination measuring meter

    International Nuclear Information System (INIS)

    This paper introduces an instrument for measuring the radioactive contamination. Some home-made CMOS integrated circuits were adopted in the instrument. It provides a six-digit display. Its highest counting rate is 106/sec. It can work on AC or DC voltage and its working current is less than 72 mA. It is a protable instrument and can be used in laboratories to measure radioactivity of the samples

  18. Full field imaging based instantaneous hyperspectral absolute refractive index measurement

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Justin S [ORNL; Boudreaux, Philip R [ORNL

    2012-01-01

    Multispectral refractometers typically measure refractive index (RI) at discrete monochromatic wavelengths via a serial process. We report on the demonstration of a white light full field imaging based refractometer capable of instantaneous multispectral measurement of absolute RI of clear liquid/gel samples across the entire visible light spectrum. The broad optical bandwidth refractometer is capable of hyperspectral measurement of RI in the range 1.30 1.70 between 400nm 700nm with a maximum error of 0.0036 units (0.24% of actual) at 414nm for a = 1.50 sample. We present system design and calibration method details as well as results from a system validation sample.

  19. Absolute stress measurements at the rangely anticline, Northwestern Colorado

    Science.gov (United States)

    de la Cruz, R. V.; Raleigh, C.B.

    1972-01-01

    Five different methods of measuring absolute state of stress in rocks in situ were used at sites near Rangely, Colorado, and the results compared. For near-surface measurements, overcoring of the borehole-deformation gage is the most convenient and rapid means of obtaining reliable values for the magnitude and direction of the state of stress in rocks in situ. The magnitudes and directions of the principal stresses are compared to the geologic features of the different areas of measurement. The in situ stresses are consistent in orientation with the stress direction inferred from the earthquake focal-plane solutions and existing joint patterns but inconsistent with stress directions likely to have produced the Rangely anticline. ?? 1972.

  20. Measurement of Absolute Acoustic Strain by Non-Contact Technique

    Science.gov (United States)

    Jayaraman, Subash; Pedrick, Michael; Tittmann, Bernhard

    2006-03-01

    Some ultrasonic applications require non-contact techniques because the target material is not easily accessible. In such cases laser-based and air-coupled ultrasonic techniques play a major role but commonly significant transmission loss is known to occur especially at higher frequencies. Therefore, it becomes imperative to know the amount of absolute acoustic strain achieved for a given application. In this paper, we report on the use of laser-based techniques to measure absolute strain on the face of vibrating rods excited under various scenarios. These include contact and air-coupled excitation at frequencies at resonance, as well as a factor of 100 below and above the resonance. The limit of our out-of-plane displacement measurement appears to be about 5 nanometers. Strains as high as 10-6 have been obtained. The paper will describe the details of the ultrasonic techniques and some of the applications. The data are compared to theoretical and simulated strain calculations.

  1. AWID - an absolutely measuring stress cell using the compensation technique

    International Nuclear Information System (INIS)

    According to the measuring principle of the stress cell explained in this report, stresses can be measured without materials parameters of the cell influencing the measurements, so that calibration measurements are not required for this absolutely measuring cell. There is no temperature dependence either. The report discusses the functioning mode which is based on evaluation of a gap in the resistance of the cell which is induced when two sheets move apart from each other in the process of pumping hydraulic oil, at the point when external pressure is reached. Theoretical studies were supplemented by laboratory tests both in an autoclave and in a tube filled with salt rock grus, under a uniaxial press. The error observed with measurements in an oil-pressure autoclave was within the order of magnitude of the reading accuracy of the measuring equipment, i.e. it was less than 0.3% at 150 bar. This is to be taken as the error to be attributed to the cell. (orig.)

  2. Deconstructing European Poverty Measures: What Relative and Absolute Scales Measure

    Science.gov (United States)

    Burkhauser, Richard V.

    2009-01-01

    Forster and d'Ercole (2009) outline the dominant method of conceptualization and operationalization of European poverty measures that informed the EU in its development of the questionnaire for the European Union--Survey of Income and Living Conditions (EU-SILC). They do so in the context of their explanation of how the Organization for Economic…

  3. Precise measurements of the absolute ?-ray emission probabilities of (223)Ra and decay progeny in equilibrium.

    Science.gov (United States)

    Collins, S M; Pearce, A K; Regan, P H; Keightley, J D

    2015-08-01

    Precise measurements of the absolute ?-ray emission probabilities have been made of radiochemically pure solutions of (223)Ra in equilibrium with its decay progeny, which had been previously standardised by 4?(liquid scintillation)-? digital coincidence counting techniques. Two high-purity germanium ?-ray spectrometers were used which had been accurately calibrated using a suite of primary and secondary radioactive standards. Comparison of the activity concentration determined by the primary technique against ?-ray spectrometry measurements using the nuclear data evaluations of the Decay Data Evaluation Project exhibited a range of ~18% in the most intense ?-ray emissions (>1% probability) of the (223)Ra decay series. Absolute ?-ray emission probabilities and standard uncertainties have been determined for the decay of (223)Ra, (219)Rn, (215)Po, (211)Pb, (211)Bi and (207)Tl in equilibrium. The standard uncertainties of the measured ?-ray emission probabilities quoted in this work show a significant improvement over previously reported ?-ray emission probabilities. Correlation coefficients for pairs of the measured ?-ray emission probabilities from the decays of the radionuclides (223)Ra, (219)Rn and (211)Pb have been determined and are presented. The ?-transition probabilities of the (223)Ra have been deduced from P(?+ce) balance using the ?-ray emission probabilities determined in this work with some agreement observed with the published experimental values of the ?-emission probabilities. PMID:25933406

  4. Absolute measurement of neutron fluxes inside the reactor core

    International Nuclear Information System (INIS)

    The subject of this work is the development and study of two methods of neutron measurements in nuclear reactors, the new method of high neutron flux measurements and the Li6-semiconductor neutron spectrometer. This work is presented in four sections: Section I. The introduction explains the need for neutron measurements in reactors. A critical survey is given of the existing methods of high neutron flux measurement and methods of fast neutron spectrum determination. Section II. Theoretical basis of the work of semiconductor counters and their most important characteristics are given. Section III. The main point of this section is in presenting the basis of the new method which the author developed, i.e., the long-tube method, and the results obtained by it, with particular emphasis on absolute measurement of high neutron fluxes. Advantages and limitations of this method are discussed in details at the end of this section. Section IV. A comparison of the existing semiconductor neutron spectrometers is made and their advantages and shortcomings underlined. A critical analysis of the obtained results with the Li6-semiconductor spectrometer with plane geometry is given. A new type of Li6-semiconductor spectrometer is described, its characteristics experimentally determined, and a comparison of it with a classical Li6-spectrometer made (author)

  5. Absolute measurement of undulator radiation in the extreme ultraviolet

    International Nuclear Information System (INIS)

    The spectral brightness of undulator radiation emitted by the model PMU-1 incorporated in the SOR-RING, the dedicated synchrotron radiation source in Tokyo, has been studied in the extreme ultraviolet region from 21.6 to 72.9 eV as a function of the electron energy #betta#, the field parameter K, and the angle of observation THETA in the absolute scale. A series of measurements covering the first and the second harmonic component of undulator radiation was compared with the fundamental formula lambdasub(n)=lambda0/2n#betta#2(1+K2/2+#betta#2THETA2), and the effects of finite emittance were studied. The brightness at the first peak was smaller than the theoretical value, while an enhanced second harmonic component was observed. (orig.)

  6. Different Kinds of DIF: A Distinction between Absolute and Relative Forms of Measurement Invariance and Bias

    Science.gov (United States)

    Borsboom, Denny; Mellenbergh, Gideon J.; Van Heerden, Jaap

    2002-01-01

    In this article, a distinction is made between absolute and relative measurement. Absolute measurement refers to the measurement of traits on a group-invariant scale, and relative measurement refers to the within-group measurement of traits, where the scale of measurement is expressed in terms of the within-group position on a trait. Relative…

  7. Absolute interferometric distance measurement using a FM-demodulation technique

    Science.gov (United States)

    Fischer, Edgar; Dalhoff, Ernst; Heim, Silke; Hofbauer, Ulrich; Tiziani, Hans J.

    1995-09-01

    We propose an interferometric method for measuring absolute distances larger than the wavelength. A laser diode is used as a light source. The principle of operation is based on multiple-wavelength interferometry that uses a modulated light source. This method uses the fact that the wavelength of light emitted by the laser diode can be varied by means of the injection current. The modulation of the injection current in combination with the optical heterodyne technique causes a high-frequency phase-modulated detector signal. The phase deviation of the signal is a measure of the optical path difference in the interferometer. By FM demodulation of the detector output with a phase-locked loop demodulator, the optical path difference can be determined directly without the classical ambiguity problem of interferometry. The measuring range in the experiments was limited to 50 mm by the maximum travel range of the used specimen translation stage. Because of the inherent light sensitivity of the method described, the rangefinder can be used for three-dimensional profile measurements on a wide variety of objects, even on diffuse scattering surfaces.

  8. Measured and modelled absolute gravity changes in Greenland

    DEFF Research Database (Denmark)

    Nielsen, Jens Emil; Forsberg, René

    2014-01-01

    In glaciated areas, the Earth is responding to the ongoing changes of the ice sheets, a response knownas glacial isostatic adjustment (GIA). GIA can be investigated through observations of gravity change.For the ongoing assessment of the ice sheets mass balance, where satellite data are used, the study ofGIA is important since it acts as an error source. GIA consists of three signals as seen by a gravimeter onthe surface of the Earth. These signals are investigated in this study. The ICE-5G ice history and recentlydeveloped ice models of present day changes are used to model the gravity change in Greenland. Theresult is compared with the initial measurements of absolute gravity (AG) change at selected GreenlandNetwork (GNET) sites.We find that observations are highly influenced by the direct attraction from the ice and ocean. Thisis especially evident in the measurements conducted at the GNET station near the Helheim Glacier.The effect of the direct attraction diminishes at sites that are more than one degreefrom the source.Here, the dominant signal is the effect of the elastic signal from present day ice mass changes. We findagreement between the measured and modelled gravity changes at all but one site. This agreement onlyholds when the direct attraction is considered. For one site, there is no agreement, indicating that someimprovements to the modelling results or the processing of the gravity data are needed. In addition, moreAG measurements are needed to strengthen the time series of gravity change.

  9. Measuring the absolute quantum efficiency of luminescent materials

    Energy Technology Data Exchange (ETDEWEB)

    Rohwer, Lauren Shea [Sandia National Laboratories, P.O. Box 5800, MS-0892, Albuquerque, NM 87185-0892 (United States)]. E-mail: leshea@sandia.gov; Martin, James E. [Sandia National Laboratories, P.O. Box 5800, MS-0892, Albuquerque, NM 87185-0892 (United States)

    2005-11-15

    A measurement system and mathematical procedure are developed for determining the absolute quantum efficiency (QE), of luminescent materials. This technique, based on absorption of diffuse light within an integrating sphere, is applied to fluorescent laser dyes and conventional phosphor powders. The system described is tested for excitation in the near-UV and blue regions, but can be applied to higher energy excitation (UV), as well as lower energy excitation in the visible to near-IR, with the appropriate photodetectors and optical filters. The system was tested on both liquid and solid samples such as Coumarin 500 (CM500) dye in methanol and ethyl acetate; Rhodamine 6G in ethanol; and a variety of powder phosphors. The QE of quinine sulfate dihydrate solution (5x10{sup -3} M in 0.1 N H{sub 2}SO{sub 4}), a NIST fluorescence standard, was found to be in good agreement with the NIST value under 390 nm excitation. The accuracy of this measurement technique is acceptable for samples with absorption cross sections greater than {approx}6 mm{sup 2}.

  10. Measuring the absolute quantum efficiency of luminescent materials

    International Nuclear Information System (INIS)

    A measurement system and mathematical procedure are developed for determining the absolute quantum efficiency (QE), of luminescent materials. This technique, based on absorption of diffuse light within an integrating sphere, is applied to fluorescent laser dyes and conventional phosphor powders. The system described is tested for excitation in the near-UV and blue regions, but can be applied to higher energy excitation (UV), as well as lower energy excitation in the visible to near-IR, with the appropriate photodetectors and optical filters. The system was tested on both liquid and solid samples such as Coumarin 500 (CM500) dye in methanol and ethyl acetate; Rhodamine 6G in ethanol; and a variety of powder phosphors. The QE of quinine sulfate dihydrate solution (5x10-3 M in 0.1 N H2SO4), a NIST fluorescence standard, was found to be in good agreement with the NIST value under 390 nm excitation. The accuracy of this measurement technique is acceptable for samples with absorption cross sections greater than ?6 mm2

  11. Radioactivity monitoring network: Measurements 1987

    International Nuclear Information System (INIS)

    Four papers are presented: radionuclide concentration measurement in aerosols, surface water and the wastes of the Vienna Central Clarification Plant respectively, and on tritium in Austrian lakes and rivers. (qui)

  12. Radioactive Beam Measurements to Probe Stellar Explosions

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Michael Scott [ORNL

    2010-01-01

    Unique beams of unstable nuclei from the Holi eld Radioactive Ion Beam Facility at Oak Ridge National Laboratory are being used to measure the thermonuclear reactions that occur in novae, X-ray bursts, and supernovae. The astrophysical impact of these measurements is determined by synergistic nuclear data evaluations and element synthesis calculations. Results of recent measurements and explosion simulations are brie y described, along with future plans and software research tools for the community.

  13. Radioactivity measurements on live Bewick's Swans

    International Nuclear Information System (INIS)

    Measurements made on 46 live swans at Slimbridge using portable high resolution hyperpure germanium gamma ray spectrometry equipment are described. Laboratory measurements are also reported on two swans which died of natural causes or of flying accidents. The implications of the measured radioactivity levels are discussed in relation to the suggestion that they might have been affected by the Chernobyl accident on their migration. (UK)

  14. The correction of vibration in frequency scanning interferometry based absolute distance measurement system for dynamic measurements

    Science.gov (United States)

    Lu, Cheng; Liu, Guodong; Liu, Bingguo; Chen, Fengdong; Zhuang, Zhitao; Xu, Xinke; Gan, Yu

    2015-10-01

    Absolute distance measurement systems are of significant interest in the field of metrology, which could improve the manufacturing efficiency and accuracy of large assemblies in fields such as aircraft construction, automotive engineering, and the production of modern windmill blades. Frequency scanning interferometry demonstrates noticeable advantages as an absolute distance measurement system which has a high precision and doesn't depend on a cooperative target. In this paper , the influence of inevitable vibration in the frequency scanning interferometry based absolute distance measurement system is analyzed. The distance spectrum is broadened as the existence of Doppler effect caused by vibration, which will bring in a measurement error more than 103 times bigger than the changes of optical path difference. In order to decrease the influence of vibration, the changes of the optical path difference are monitored by a frequency stabilized laser, which runs parallel to the frequency scanning interferometry. The experiment has verified the effectiveness of this method.

  15. System for measuring radioactivity of labelled biopolymers

    International Nuclear Information System (INIS)

    A system is described for measuring radioactivity of labelled biopolymers, comprising: a set of containers adapted for receiving aqueous solutions of biological samples containing biopolymers which are subsequently precipitated in said containers on particles of diatomite in the presence of a coprecipitator, then filtered, dissolved, and mixed with a scintillator; radioactivity measuring means including a detection chamber to which is fed the mixture produced in said set of containers; an electric drive for moving said set of containers in a stepwise manner; means for proportional feeding of said coprecipitator and a suspension of diatomite in an acid solution to said containers which contain the biological sample for forming an acid precipitation of biopolymers; means for the removal of precipitated samples from said containers; precipitated biopolymer filtering means for successively filtering the precipitate, suspending the precipitate, dissolving the biopolymers mixed with said scintillator for feeding of the mixture to said detection chamber; a system of pipelines interconnecting said above-recited means; and said means for measuring radioactivity of labelled biopolymers including, a measuring cell arranged in a detection chamber and communicating with said means for filtering precipitated biopolymers through one pipeline of said system of pipelines; a program unit electrically connected to said electric drive, said means for acid precipatation of biopolymers, said means for the removal of precipitated samples from said containers, said filtering means, and said radioactivity measuring device; said program unit adapted to periodically switch on and off the above-recited means and check the sequence of the radioactivity measuring operations; and a control unit for controlling the initiation of the system and for selecting programs

  16. Nondestructive measurement of environmental radioactive strontium

    Science.gov (United States)

    Saiba, Shuntaro; Okamiya, Tomohiro; Tanaka, Saki; Tanuma, Ryosuke; Totsuka, Yumi; Murata, Jiro

    2014-03-01

    The Fukushima Daiichi nuclear power plant accident was triggered by the 2011 Great East Japan Earthquake. The main radioactivity concerns after the accident are I-131 (half-life: 8.0 days), Cs-134 (2.1 years), Cs-137 (30 years), Sr-89 (51 days), and Sr-90 (29 years). We are aiming to establish a new nondestructive measurement and detection technique that will enable us to realize a quantitative evaluation of strontium radioactivity without chemical separation processing. This technique is needed to detect radiation contained in foods, environmental water, and soil, to prevent us from undesired internal exposure to radiation.

  17. Nondestructive measurement of environmental radioactive strontium

    OpenAIRE

    Saiba Shuntaro; Okamiya Tomohiro; Tanaka Saki; Tanuma Ryosuke; Totsuka Yumi; Murata Jiro

    2014-01-01

    The Fukushima Daiichi nuclear power plant accident was triggered by the 2011 Great East Japan Earthquake. The main radioactivity concerns after the accident are I-131 (half-life: 8.0 days), Cs-134 (2.1 years), Cs-137 (30 years), Sr-89 (51 days), and Sr-90 (29 years). We are aiming to establish a new nondestructive measurement and detection technique that will enable us to realize a quantitative evaluation of strontium radioactivity without chemical separation processing. This technique is nee...

  18. Nondestructive measurement of environmental radioactive strontium

    Directory of Open Access Journals (Sweden)

    Saiba Shuntaro

    2014-03-01

    Full Text Available The Fukushima Daiichi nuclear power plant accident was triggered by the 2011 Great East Japan Earthquake. The main radioactivity concerns after the accident are I-131 (half-life: 8.0 days, Cs-134 (2.1 years, Cs-137 (30 years, Sr-89 (51 days, and Sr-90 (29 years. We are aiming to establish a new nondestructive measurement and detection technique that will enable us to realize a quantitative evaluation of strontium radioactivity without chemical separation processing. This technique is needed to detect radiation contained in foods, environmental water, and soil, to prevent us from undesired internal exposure to radiation.

  19. ATLAS ALFA—measuring absolute luminosity with scintillating fibres

    CERN Document Server

    Franz, S

    2009-01-01

    ALFA is a high-precision scintillating fibre tracking detector under construction for the absolute determination of the LHC luminosity at the ATLAS interaction point. This detector, mounted in so-called Roman Pots, will track protons elastically scattered under ?rad angles at IP1.In total there are four pairs of vertically arranged detector modules which approach the LHC beam axis to mm distance. Each detector module consists of ten layers of two times 64 scintillating fibres each (U and V planes). The fibres are coupled to 64 channels Multi-Anodes PhotoMultipliers Tubes read out by compact front-end electronics. Each detector module is complemented by so-called overlap detectors: Three layers of two times 30 scintillating fibres which will be used to measure the relative positioning of two vertically arranged main detectors. The total number of channels is about 15000. Conventional plastic scintillator tiles are mounted in front of the fibre detectors and will serve as trigger counter. The extremely restric...

  20. Portable laboratories for radioactivity measurements

    International Nuclear Information System (INIS)

    The portable radiometric laboratories LARA-10, LARA-GS, LARA-86 and ALARA-10 designed, developed and produced at the Boris Kidric Institute are described. Earlier models (LARA-1, LARA-1D, LARA-2 and LARA-5) are presented in brief. The basic characteristics of the devices and methods of measurements are given. All the instruments are battery operated and almost all can also use 220V/50Hz supply. They are a very suitable facility for radiological monitoring of soil, water, food, clothes etc., when working in field conditions (author)

  1. Accurate absolute measurement of trapped Cs atoms in a MOT

    Energy Technology Data Exchange (ETDEWEB)

    Talavera O, M.; Lopez R, M.; Carlos L, E. de [Division de Tiempo y Frecuencia, Centro Nacional de Metrologia, CENAM, km 4.5 Carretera a los Cues, El Marques, 76241 Queretaro (Mexico); Jimenez S, S. [Centro de Investigacion y Estudios Avanzados del lPN, Unidad Queretaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, 76230 Queretaro (Mexico)

    2007-07-01

    A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrologia, CENAM, in Mexico. This MOT is part of a primary frequency standard based on ultra-cold Cs atoms, called CsF-1 clock, under development at CENAM. In this Cs MOT, we use the standard configuration ({sigma}{sup +} - {sigma}{sup -}) 4-horizontal 2-vertical laser beams 1.9 cm in diameter, with 5 mW each. We use a 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Emission linewidth of the master laser is l MHz. In order to amplify the light of the master laser, a 50 mW, 852 nm AlGaAs laser is used as slave laser. This slave laser is stabilized by light injection technique. A 12 MHz red shift of the light is performed by two double passes through two Acusto-Optic Modulators (AOMs). The optical part of the CENAMs MOT is very robust against mechanical vibration, acoustic noise and temperature changes in our laboratory, because none of our diode lasers use an extended cavity to reduce the linewidth. In this paper, we report results of our MOT characterization as a function of several operation parameters such as the intensity of laser beams, the laser beam diameter, the red shift of light, and the gradient of the magnetic field. We also report accurate absolute measurement of the number of Cs atoms trapped in our Cs MOT. We found up to 6 x 10{sup 7} Cs atoms trapped in our MOT measured with an uncertainty no greater than 6.4%. (Author)

  2. Measurement and analysis of radioactive substances

    International Nuclear Information System (INIS)

    Here are gathered the abstracts presented to the 3. summer university of the year 2001 whose main themes were the destructive (5 conferences) and nondestructive (8 conferences) analyses applied to nuclear industry. The points of view of different organisms (as DSIN: Directorate for the Safety of Nuclear Installations, IPSN: Institute of Nuclear Protection and Safety, OPRI: Office of Protection against Ionizing Radiations, TUI: Institute for Transuranium Elements, COGEMA, EDF: Electric Utilities, ANDRA: French National Agency for Radioactive Waste Management, CRLC Val d'Aurelle, France) concerning the needs involved in nuclear facilities control, the methods of radionuclide speciation in use internationally, the measurements and analyses of radioactive substances are given too as well as some general concepts concerning 1)the laser-matter interaction 2)the ions production 3)the quality applied to the measurements and analyses 4)the standard in activity metrology. (O.M.)

  3. Error calculations statistics in radioactive measurements

    International Nuclear Information System (INIS)

    Basic approach and procedures frequently used in the practice of radioactive measurements.Statistical principles applied are part of Good radiopharmaceutical Practices and quality assurance.Concept of error, classification as systematic and random errors.Statistic fundamentals,probability theories, populations distributions, Bernoulli, Poisson,Gauss, t-test distribution,?2 test, error propagation based on analysis of variance.Bibliography.z table,t-test table, Poisson index ,?2 test

  4. Methods applied for measuring radioactive environmental isotopes

    International Nuclear Information System (INIS)

    Hydrologic applications of the radioactive environmental isotopes 3H, 14C and 85Kr require measuring methods, whose detection limits range 1 to 2 magnitudes below the concentrations of these radionuclides in recently generated groundwater. The study gives a survey about the corresponding analytic methods, which are applicable today at the GSF Institute for Radiohydrometry. In addition some information about the detection of 39Ar is provided. (orig.)

  5. Cross section measurements on radioactive samples

    International Nuclear Information System (INIS)

    We have developed a system over the past few years at the Manuel Lujan, Jr. Neutron Scattering Center (LANSCE) for making (n,p) and (n,?) measurements on (mainly) radioactive nuclei. Measurements have included 7Be(n,p)7Li, 14N(n,p)14C, 17O(n,?)14C, 22Na(n,p)22Ne, 22Na(n,?)19F, 35Cl(n,p)35S and 36Cl(n,p)36S. The major basic physics motivation for these measurements has been the nuclear astrophysics to be learned. Currently, we are assembling a 4? detector of barium fluoride (BaF2) for making (n,?) measurements on radioactive nuclei with relatively short half lives. Once operational, this new detector should allow us to expand our measurements to many more nuclei, and to a broader range of nuclear physics and nuclear astrophysics issues addressed. Results of recent measurements are given and future plans are discussed. 38 refs., 2 figs

  6. National network of radioactivity measurement in environment

    International Nuclear Information System (INIS)

    This document constitutes the report of management for the year 2006 of the national network of measurement of radioactivity in environment, instituted by the article R.1333-11 of the Public Health code. According to the 5. of the decree of 27. june 2005, the Institute of radiation protection and nuclear safety (I.R.S.N.) has for mission to write every year a report of management of the national network of radioactivity measurement in environment. This report has for principal objectives: to do an evaluation on organisation and functioning of the piloting committee; to realize a synthesis on the different tasks lead by the working groups; as well as on the human and financial resources devoted to this project; to debrief on the development project of the national network information system. This report must allow to the network actors, as to the professional people and the public, to understand the functioning of the national network and the process implemented for the development of centralization, management and public diffusion tools, of the radioactivity data in environment. The year 2006 was marked by the opening of an Internet gate of the national network. (N.C.)

  7. Groundwater measurements by means of radioactive tracers

    Energy Technology Data Exchange (ETDEWEB)

    Drost, W.

    1986-01-01

    Groundwater tracing by multi- and single-well techniques by means of well selected radioactive tracers, which have several advantages over conventional tracers, includes measurement of transport parameters of groundwater flow in saturated rock as well as moisture movement in the unsatured zone. Multi-well techniques give information on the spatial and temporal tracer distribution over a given distance, and tracer evolution at a given point is measured by single-well techniques. While field methods for the evaluation of groundwater flow by convection and of an aquifer's transmissivity are widely useful, the process of hydrodynamic dispersion in subsurface flow demands better understanding. (orig.).

  8. Natural radioactivity measurements of Kudligi, Karnataka

    International Nuclear Information System (INIS)

    The present work deals with the preliminary studies on the concentration of the natural radionuclides namely 238U, 232Th and 40K in soil and rock samples around Kudligi City. The radioactivity of samples has been analyzed using a high-resolution gamma ray spectrometry system. The measured mean concentrations in Bq/kg are 24.94, 22.93, 551.89 for 238U, 232Th and 40K respectively. The mean dose rate estimated is 48.82 nGyh-1 at 1.0 meter above the ground level. These results indicate that the dose to the public due to natural radioactivity in this region is below the normal limit set by the national standards. (author)

  9. Accurate absolute measurement of trapped Cs atoms in a MOT

    Scientific Electronic Library Online (English)

    M., Talavera O.; M., López R.; E., de Carlos L.; S., Jiménez S.

    2007-10-01

    Full Text Available Una Trampa Magneto-Óptica (MOT) de Cs-133 se ha desarrollado en la División de Tiempo y Frecuencia del Centro Nacional de Metrología, CENAM, en Mexico. Esta MOT es parte de un patrón primario de frecuencia basado en átomos ultra fríos de Cs, llamado reloj CsF-1 que se encuentra en desarrollo en el C [...] ENAM. En esta MOT de Cs, se emplea la configuracion estándar (?+ - ?-) de 4 haces laser horizontales y 2 verticales de 1.9 cm de diametro con 5 mW de potencia cada uno. Se utiliza un láser DBR de 852 nm y 5 mW como láser maestro estabilizado por espectroscopia de saturación. El ancho de línea de emision del láser maestro es de 1 MHz. Para amplificar la luz del láser maestro, se emplea un laser esclavo de AlGaAs de 852 nm y 50 mW de potencia. Este láser esclavo es estabilizado por la técnica de inyección de luz. Se realiza un corrimiento de la luz al rojo de 12 MHz por un doble paso a través de dos Moduladores Acusto-Ópticos (AOMs). La parte óptica de la MOT del CENAM es muy robusta contra la vibracion mecánica, el ruido acústico y los cambios de temperatura en el laboratorio, debido a que ninguno de los diodos laser emplea una cavidad extendida para reducir el ancho de línea. En este trabajo se reportan los resultados de la caracterizacion de la MOT como una función de varios parámetros de operación tales como: intensidad y diámetro de los haces láser, corrimiento al rojo de la luz y el gradiente de campo magnético. También se reportan mediciones absolutas del número de átomos de Cs atrapados en la MOT. Se encontraron mas de 6 x 10(7) atomos de Cs atrapados, medidos con una incertidumbre que en ningún caso es mayor a 6.4%. Abstract in english A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrología, CENAM, in Mexico. This MOT is part of a primary frequency standard based on ultra-cold Cs atoms, called CsF-1 clock, under development at CENAM. In this Cs MOT, we use the [...] standard configuration (?+ - ?-) 4-horizontal 2-vertical laser beams 1.9 cm in diameter, with 5 mW each. We use a 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Emission linewidth of the master laser is 1 MHz. In order to amplify the light of the master laser, a 50 mW, 852 nm AlGaAs laser is used as slave laser. This slave laser is stabilized by light injection technique. A 12 MHz red shift of the light is performed by two double passes through two Acusto-Optic Modulators (AOMs). The optical part of the CENAMs MOT is very robust against mechanical vibration, acoustic noise and temperature changes in our laboratory, because none of our diode lasers use an extended cavity to reduce the linewidth. In this paper, we report results of our MOT characterization as a function of several operation parameters such as the intensity of laser beams, the laser beam diameter, the red shift of light, and the gradient of the magnetic field. We also report accurate absolute measurement of the number of Cs atoms trapped in our Cs MOT. We found up to 6 x 10(7) Cs atoms trapped in our MOT measured with an uncertainty no greater than 6.4%.

  10. A double fission chamber for absolute fission rate measurements in power reactor environments

    International Nuclear Information System (INIS)

    A prototype fission chamber has been extensively tested and several chambers assembled in preparation for the Fast Flux Test Facility - Reactor Characterization Program (FFTF - RCP). The major portion of our report concerns the chamber design and performance characteristics. The absolute efficiency of the device will not be explicitly discussed. In ruggedizing the chamber, great care has been taken not to significantly alter the absolute efficiency as compared to the more conventional NBS configuration. This configuration and the measurement of absolute fission rates have already been rigorously discussed in an earlier report. The FFTF characterization effort will be reported in a future paper after the measurements have been completed

  11. Measurement of the absolute gas gain and gain variations study in straw-tube detectors

    International Nuclear Information System (INIS)

    We present the results of the absolute gas gain measurement of a straw drift-tube filled with a binary gaseous mixture Ar-CO2(90-10) at 2 bar absolute pressure. The measurement has been performed using an intense 1.3 GBq 137Cs-source producing the primary ionization current. The results, as a function of the high voltage and gas parameters, were fitted and parameterized with a Diethorn's formula

  12. Why the Bradley aberration cannot be used to measure absolute speeds. A comment

    CERN Document Server

    Kassner, K

    2002-01-01

    In a recent article in this journal [G. Sardin, Measure of the absolute speed through the Bradley aberration of light beams on a three-axis frame, Europhys. Lett. 53 (2001) 310], Sardin proposed to use the Bradley aberration of light for the construction of a speedometer capable of measuring absolute speeds. The purpose of this comment is to show that the device would not work.

  13. Absolute dose measurement Gafchromic R EBT2 movies. Case Study of Kaposis sarcoma

    International Nuclear Information System (INIS)

    Because of its high spatial resolution, low energy dependence and good response over a wide energy range, EBT2 Gafchromic films are widely used in many applications in radiotherapy for measuring relative dose. Despite being the most common use can be used to measure absolute dose. This text is an example of using films as EBT2 for in vivo absolute dose in a Kaposis sarcoma.

  14. Radioactive Measurements for KamLAND

    Science.gov (United States)

    Djurcic, Zelimir; Piepke, Andreas

    2000-11-01

    KamLAND will be the largest low-energy anti-neutrino detector ever built. It will study a wide range of science including particle physics, geophysics and astrophysics. Main objective of the project is to search for neutrino oscillations in disappearance mode by studying the flux and energy spectrum of anti-neutrinos produced by Japanese commercial nuclear reactors. The detector is exposed to low-energy anti-neutrinos coming from 16 commercial nuclear power stations, 150-200 km away from the experimental site. The extraordinary beseline and low anti-neutrino energies give us the possibility, for the first time, to access the large mixing angle solution of the solar neutrino problem in a terrestrial experiment and therefore provide a solar model independent test for neutrino oscillations. The quality of these measurements will depend on the extent to which the radioactive contamination, and hence the background, can be controlled. We expect the background to be dominated by the internal radioactivity of the scintillator. Goal of our project is to verify that the liquid scintillator has a purity level of 10-10 and 10-14 g/g in K and U/Th as required to carry out KamLAND's reactor neutrino program. We are working on a developement of a Neutron Activation Analysis to provide such test. Result and status of the project will be discussed.

  15. Ethernet-based automation in radioactivity measurements

    International Nuclear Information System (INIS)

    The paper describes an integrated radioactivity measurements laboratory involved in a New York State program of monitoring environmental radioactivity and bioassay samples. The laboratory is set up as a comprehensive Ethernet network that integrates radiation detectors, electronics hardware components as well as software automation and communications. Two DEC VAXstations 3100 and 3200 are central to the system. The VAXstation 3100 runs the Canberra/Nuclear Data Genie data-acquisition program. The Acquisition Interface Modules interface the ADCs to the Ethernet. Using the DEC Pathworks, the VAXstation 3100 is also a server for the Ethernet-based network of several 486 and 386 PCs. A designated PC can display the Genie acquisition window, in addition to the main window at VAXstation 3100. Another PC collects data from several NaI detectors using the Oxford/Nucleus DMR-II program. The paper also describe the plans for the future upgrades such as installation of VAXstation 4000/90 as well as interfacing the proportional counters and surface barrier detectors to the network

  16. Measurement of absolute elastic differential cross-sections for positron-methane scattering

    International Nuclear Information System (INIS)

    We have measured absolute elastic differential cross-sections (DCS's) for positrons scattered from methane over the energy range 6 to 200 eV at scattering angles from 30 to 135 degrees. We use a crossed beam experiment to obtain the DCS for electron-methane scattering at 20 eV which is then normalized at 90 degrees to the absolute measurements of Tanaka et al. This normalization factor is used to obtain absolute positron DCS's from our relative positron DCS measurements. Our absolute DCS's are in qualitative agreement with the calculations of Jain and Gianturco. Because of the similarity in shape between the total cross-section curves for positron-methane and positron-argon scattering, it is of interest to determine whether a resonance-like structure seen in the elastic DCS for positron-argon scattering at intermediate energies also appears in the DCS for positron-methane scattering. No such structure has yet been found

  17. Absolute beam emittance measurements at RHIC using ionization profile monitors

    Energy Technology Data Exchange (ETDEWEB)

    Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Connolly, R [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Summers, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-08-15

    In the past, comparisons between emittance measurements obtained using ionization profile monitors, Vernier scans (using as input the measured rates from the zero degree counters, or ZDCs), the polarimeters and the Schottky detectors evidenced significant variations of up to 100%. In this report we present studies of the RHIC ionization profile monitors (IPMs). After identifying and correcting for two systematic instrumental errors in the beam size measurements, we present experimental results showing that the remaining dominant error in beam emittance measurements at RHIC using the IPMs was imprecise knowledge of the local beta functions. After removal of the systematic errors and implementation of measured beta functions, precise emittance measurements result. Also, consistency between the emittances measured by the IPMs and those derived from the ZDCs was demonstrated.

  18. Absolute intensity measurement of internal Bremsstrahlung from 57Co

    International Nuclear Information System (INIS)

    The Internal Bremsstrahlung (IB) spectrum from 57Co has been re-measured in two separate experiments. In the measurement of IB in coincidence with 122 keV gamma rays of 57Fe, the energy range of IB spectrum could be extended below 300 keV. In the other measurement involving IB in coincidence with K-X-rays of 57Fe, the uncertainty in the end-point-energy value has reduced by almost a factor of two. In both cases, the measured intensity of IB spectra shows a good agreement with the theoretical predictions of Martin and Glauber. (author)

  19. Radioactivity measurements applied to glaciers and lake sediments

    International Nuclear Information System (INIS)

    The behaviour of glaciers, polar ice-caps and lakes can be studied by means of natural and artificial radioactivity measurements conducted on snow (Alps, Arctic and Antarctic) and sediments samples. The nuclear decay of elements (210Pb and 238U filiation products) and nuclear events (atmospheric thermonuclear tests: 1954 and 1962-63; Chernobyl accident: 1986) allow an absolute dating of corresponding layers. These determinations need radiochemical separations (electro-plating, ion exchange filters), followed by ultra low level alpha and gamma spectrometries, or beta counting (137Cs, 90Sr). The high purity - N type - germanium detector (Compton-suppressed) allows the 210Pb analysis at 46.52 keV, enabling a direct comparison with 210Po alpha spectrometry. Typical applications concern primarily dating, and the determination of mean annual accumulation rates of glaciers, sedimentation rate and mixing time in lakes, with their associated spatio-temporal variations. These measurements give access to the global fallouts of radionuclides and to meteorological parameters: air to snow (or sediment) transfer, deposition processes and atmospheric circulation

  20. The measurement of the radioactive materials in food

    International Nuclear Information System (INIS)

    Since food contained radioactive materials released from Fukushima Daiichi nuclear power station accident initiated by Great East Japan earthquake disaster, new reference values of radioactive materials corresponding to 1 mSv/year was set up in April 2012 based on food hygiene law so as to ensure food safety and security for the people. As the request of development of continuous measurement of radioactive materials in food as it is with satisfying this criteria, continuous radioactive cesium measuring device had been developed for screening radioactive materials in food with measurement lower limit of 25 Bq/kg corresponding one fourth of new reference values. The device used CsI detector with CsI scintillator and Si photodiode (multi-pixel photo counter) combined. This article described outlines of the device, measurement examples (powdered food, powdered milk and tea leaves) and future perspective of device development (position sensitive detection of radioactive materials in complex shape food). (T. Tanaka)

  1. Infrastructure development of radiation measurement system for illicit radioactive materials

    International Nuclear Information System (INIS)

    On NORM (Naturally Occurring Radioactive Material) and export/import goods including the small radioactive material, it is also required for public that the level of the radiation safety and reassuring is raised to use the radiation measurement or the identification of radioactive material. Furthermore, it becomes in the age of which the necessity of radioactive material identification of the unidentified packing is strongly obtained in order to previously prevent nuclear-terrorism and dirty bomb. In NUSTEC, Infrastructure development of radiation measurement system for illicit use of radioactive materials is promoted using of the experience in measuring technique and gamma-ray spectrum measuring instrument (semiconductor detector, etc.) regulated at ISO22188 in the case of receiving a request from the government, local fire service and police. In this paper, improvement situation of the radioactive material detection equipment in our center is described. (author)

  2. Absolute measurement of ? emitters with a 4 ? counter

    International Nuclear Information System (INIS)

    The object of this work is to investigate the conditions under which the activity of ?-emitting radionuclides may be measured with a maximum of precision, and as a result to study the relevant corrections. The various problems relating to activity measurements with a 4 ? counter have been examined successively: - comparison of 4 ?, GM and proportional counters; - study of the preparation of sources; - corrections on the counting of sources; - self-absorption; - correction for absorption. The precision obtained on these measurements varies from 1.2 to 3 per cent, with the result that the 4 ? counter can be considered a very satisfactory calibration instrument. (author)

  3. Radioactivity measurements using storage phosphor technology

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Y.T. [NeuTek, Darnestown, MD (United States); Hwang, J. [Advanced Technologies and Labs. International, Rockville, MD (United States); Hutchinson, M.R. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    1995-10-01

    We propose to apply a recently developed charged particle radiation imaging concept in bio-medical research for fast, cost-effective characterization of radionuclides in contaminated sites and environmental samples. This concept utilizes sensors with storage photostimulable phosphor (SPP) technology as radiation detectors. They exhibit high sensitivity for all types of radiation and the response is linear over a wide dynamic range (>10{sup 5}), essential for quantitative analysis. These new sensors have an Active area of up to 35 cm x 43 cm in size and a spatial resolution as fine as 50 {mu}m. They offer considerable promise as large area detectors for fast characterization of radionuclides with an added ability to locate and identify hot spots. Tests with SPP sensors have found that a single alpha particle effect can be observed and an alpha field of 100 dpm/100 cm{sup 2} or a beta activity of 0.1 dpm/mm{sup 2} or gamma radiation of few {mu}R/hr can all be measured in minutes. Radioactive isotopes can further be identified by energy discrimination which is accomplished by placing different thicknesses of filter material in front of the sensor plate. For areas with possible neutron contamination, the sensors can be coupled to a neutron to charged particle converter screen, such as dysprosium foil to detect neutrons. Our study has shown that this approach can detect a neutron flux of 1 n/cm{sup 2}s or lower, again with only minutes of exposure time. The utilization of these new sensors can significantly reduce the time and cost required for many site characterization and environmental monitoring tasks. The {open_quotes}exposure{close_quotes} time for mapping radioactivity in an environmental sample may be in terms of minutes and offer a positional resolution not obtainable with presently used counting equipment. The resultant digital image will lend itself to ready analysis.

  4. Radioactivity measurements using storage phosphor technology

    International Nuclear Information System (INIS)

    We propose to apply a recently developed charged particle radiation imaging concept in bio-medical research for fast, cost-effective characterization of radionuclides in contaminated sites and environmental samples. This concept utilizes sensors with storage photostimulable phosphor (SPP) technology as radiation detectors. They exhibit high sensitivity for all types of radiation and the response is linear over a wide dynamic range (>105), essential for quantitative analysis. These new sensors have an Active area of up to 35 cm x 43 cm in size and a spatial resolution as fine as 50 ?m. They offer considerable promise as large area detectors for fast characterization of radionuclides with an added ability to locate and identify hot spots. Tests with SPP sensors have found that a single alpha particle effect can be observed and an alpha field of 100 dpm/100 cm2 or a beta activity of 0.1 dpm/mm2 or gamma radiation of few ?R/hr can all be measured in minutes. Radioactive isotopes can further be identified by energy discrimination which is accomplished by placing different thicknesses of filter material in front of the sensor plate. For areas with possible neutron contamination, the sensors can be coupled to a neutron to charged particle converter screen, such as dysprosium foil to detect neutrons. Our study has shown that this approach can detect a neutron flux of 1 n/cm2s or lower, again with only minutes of exposure time. The utilization of these new sensors can significantly reduce the time and cost required for many site characterization and environmental monitoring tasks. The open-quotes exposureclose quotes time for mapping radioactivity in an environmental sample may be in terms of minutes and offer a positional resolution not obtainable with presently used counting equipment. The resultant digital image will lend itself to ready analysis

  5. An Absolute Index (Ab-index) to Measure a Researcher’s Useful Contributions and Productivity

    OpenAIRE

    Biswal, Akshaya Kumar

    2013-01-01

    Bibliographic analysis has been a very powerful tool in evaluating the effective contributions of a researcher and determining his/her future research potential. The lack of an absolute quantification of the author’s scientific contributions by the existing measurement system hampers the decision-making process. In this paper, a new metric system, Absolute index (Ab-index), has been proposed that allows a more objective comparison of the contributions of a researcher. The Ab-index takes into ...

  6. Present status and prospects of ultralow level radioactivity measurements (3). Environmental radioactivity monitoring in Japan

    International Nuclear Information System (INIS)

    The environmental radioactivity survey in Japan is explained. There are two kinds of surveys such as monitoring around nuclear facilities and the environmental radioactivity survey. On monitoring around the nuclear facilities, its objects, monitoring at ordinary times and in an emergency, the measurement items, radioactive materials analysis, evaluation and open to the public of monitoring results and guarantee of monitoring quality are reported. On environmental radioactivity survey in wide area, its objects, environmental radioactivity survey, working organizations, fallout measurement, concentration of radon in foods, neutron dose, natural radionuclide and nuclides in relation to reprocessing plants are measured. The measurement results are opened on Web site; http://www.kankyo-hoshano.go.jp/ and http://www.search.kankyo-hoshano.go.jp/. (S.Y.)

  7. Absolute measurement of the activity of 222Rn using a proportional counter

    International Nuclear Information System (INIS)

    A measuring set-up comprising a proportional counter of calculable 222Rn efficiency and quantifiable active volume (?V222Rn efficiency is determined by computer simulation of the measured ?-spectra. The procedures necessary for absolute measurements by means of the counter are described, and the suitability of the counter for absolute measurements of the 222Rn activity is proved by experiments. Thus, a new method for the realization of the unit of activity of 222Rn is obtained, which is independent of the unit of activity of 226Ra

  8. Perfusion measurements with radioactively labelled microspheres

    International Nuclear Information System (INIS)

    The technique and the evaluation of the microsphere-method are comprehensively represented in theory and practice. Some changes and new concepts are discussed, besides the known foundations and techniques, that assure an essential methodic improvement resp. practical simplifications. Two new formulas are derived within the frame of the theoretical principles, by which the absolute flux of shorts can be calculated, i.e. on the one hand in the case of known and on the other hand in the case of unknown applied amount of indicator. The determination of the optimal indicator dose is defined and formulated mathematically with respect to the experimental conditions to be expected. The matrix method was designed for the analysis of complex gamma spectra. Hereby there is no selective error accumulation in the case of low energy radio nuclids contrary to the so far exclusively used stripping technique. The number of possible error quantities was reduced by one resp. two variables. The error of particular radio nuclid components is quantitatively computed as standard deviation by means of the theory of approximated systems of linear equations. The external measurement of distance was developed. This technique is less susceptible for errors as the aliquota i.e. whole body measurement technique. Additionally less measurement time is needed. A flexible computer program for a desk top computer was developped for the evaluation. The data from the gamma spectrometer are recorded on tipe and automatically read in by the computer. The manual input are limited to the weights of the organs and some control parameter. The output is made by a clearly arranged table by means of a lineprinter. (orig./MG)

  9. Methods of measuring radioactivity in the environment

    International Nuclear Information System (INIS)

    A variety of sampling methods have been utilized to assess the amount of deposited activity, mainly from 137Cs, from the Chernobyl accident and from nuclear weapons tests. Starting with the Chernobyl accident in 1986 sampling of air and rain was used to determine the composition and amount of radioactive debris from this accident. The resulting deposition and its removal from urban areas was then studied through measurements on sewage sludge and water. The main part of the thesis considers methods of determining the amount of radiocesium in the ground through soil sampling. In connection with soil sampling a method of optimizing the sampling procedure has been developed and tested in the areas of Sweden with high amounts of 137Cs from the Chernobyl accident. This method was then used in a survey of the activity in soil in Scania (south Sweden) with fallout activity from nuclear weapons and Chernobyl. By comparing the results from this survey with deposition calculated from precipitation measurements it was found possible to predict the deposition pattern over Scania for both nuclear weapons and Chernobyl fallout. In addition, the vertical distribution of 137Cs has been modelled and the temporal variation of the depth distribution has been described. 65 refs

  10. Methods of measuring radioactivity in the environment

    Science.gov (United States)

    Isaksson, Mats

    In this thesis a variety of sampling methods have been utilised to assess the amount of deposited activity, mainly of 137Cs, from the Chernobyl accident and from the nuclear weapons tests. Starting with the Chernobyl accident in 1986 sampling of air and rain was used to determine the composition and amount of radioactive debris from this accident, brought to southern Sweden by the weather systems. The resulting deposition and its removal from urban areas was than studied through measurements on sewage sludge and water. The main part of the thesis considers methods of determining the amount of radiocaesium in the ground through soil sampling. In connection with soil sampling a method of optimising the sampling procedure has been developed and tested in the areas of Sweden which have a comparatively high amount of 137Cs from the Chernobyl accident. This method was then used in a survey of the activity in soil in Lund and Skane, divided between nuclear weapons fallout and fallout from the Chernobyl accident. By comparing the results from this survey with deposition calculated from precipitation measurements it was found possible to predict the deposition pattern over Skane for both nuclear weapons fallout and fallout from the Chernobyl accident. In addition, the vertical distribution of 137Cs has been modelled and the temporal variation of the depth distribution has been described.

  11. Fast analysis of the radioactivity measurement data based on bluetooth

    International Nuclear Information System (INIS)

    Introduced the method that the bluetooth technique imbeds the radioactivity measurement instrument, and realized remote monitor and radioactivity measurement data quickly analysis through the use of the wireless technique-bluetooth and the portable handhold PC. Give the system design, the device select and connect, the circumstance of the software programming and actual debug. (authors)

  12. 4? proportional counter for absolute measurement of ?-emitters

    International Nuclear Information System (INIS)

    The 4? counter is commonly used to measure the activity of ? sources, the one we describe does not advance a new conception but the issue of several years of investigations. The apparatus presents good performances about the qualities commonly required in that kind of counter: detection efficiency, plateau and dead time. Moreover technical characteristics give a great flexibility in use, particularly a possibility of adaptation in a ?,? coincidence unit. (authors)

  13. The Implications for Higher-Accuracy Absolute Measurements for NGS and its GRAV-D Project

    Science.gov (United States)

    Childers, V. A.; Winester, D.; Roman, D. R.; Eckl, M. C.; Smith, D. A.

    2013-12-01

    Absolute and relative gravity measurements play an important role in the work of NOAA's National Geodetic Survey (NGS). When NGS decided to replace the US national vertical datum, the Gravity for the Redefinition of the American Vertical Datum (GRAV-D) project added a new dimension to the NGS gravity program. Airborne gravity collection would complement existing satellite and surface gravity data to allow the creation of a gravimetric geoid sufficiently accurate to form the basis of the new reference surface. To provide absolute gravity ties for the airborne surveys, initially new FG5 absolute measurements were made at existing absolute stations and relative measurements were used to transfer those measurements to excenters near the absolute mark and to the aircraft sensor height at the parking space. In 2011, NGS obtained a field-capable A10 absolute gravimeter from Micro-g LaCoste which became the basis of the support of the airborne surveys. Now A10 measurements are made at the aircraft location and transferred to sensor height. Absolute and relative gravity play other roles in GRAV-D. Comparison of surface data with new airborne collection will highlight surface surveys with bias or tilt errors and can provide enough information to repair or discard the data. We expect that areas of problem surface data may be re-measured. The GRAV-D project also plans to monitor the geoid in regions of rapid change and update the vertical datum when appropriate. Geoid change can result from glacial isostatic adjustment (GIA), tectonic change, and the massive drawdown of large scale aquifers. The NGS plan for monitoring these changes over time is still in its preliminary stages and is expected to rely primarily on the GRACE and GRACE Follow On satellite data in conjunction with models of GIA and tectonic change. We expect to make absolute measurements in areas of rapid change in order to verify model predictions. With the opportunities presented by rapid, highly accurate absolute gravimetry, we expect that GRAV-D may be affected in a number of ways. 1) Areas requiring re-measurement as a result of poor quality data or temporal change could be measured with such a new meter. With a meter capable of field measurement with observation times that are very short, surveys previously conducted only with the relative meters could be performed with the absolute meter with no loss of time and a significant increase in accuracy. 2) Regions of rapid change due to hydrological change associated with aquifers could be measured and re-measured rather quickly. Such accuracy may provide more accurate snapshots of the aquifers over time. 3) NGS conducts absolute gravity comparisons at its Table Mountain facility for validating the performance of absolute meters through their co-located operation at gravity piers. An increase in accuracy of an order of magnitude may change the entire nature of absolute meter performance evaluation.

  14. A technique for the absolute measurement of the W-value for X-rays in counting gases

    International Nuclear Information System (INIS)

    A technique was developed for the absolute measurement of the W-value (the mean energy for the production of an electron-ion pair) for low-energy X-rays in a wide range of gases at atmospheric pressures, with a standard uncertainty better than 1%. This technique is based on the absolute measurement of the primary ionization charge produced by X-ray photons from a constant intensity monoenergetic X-ray source, e.g. a long lifetime radioactive source. The ionization charge is calibrated by the number of X-ray photons absorbed in the gas, counted with a photon detector. For this purpose, a hybrid detector system was tested and its use in W-value measurements was investigated. The technique was applied to pure xenon at 825 Torr with 5.9 keV X-rays and a W-value of 21.61-0.10+0.14 eV was obtained for a 68% confidence level. The required corrections and the different factors contributing to the accuracy of the results are discussed. The advantages and limitations of this technique are explored and future developments are discussed

  15. Calibrating the absolute amplitude scale for air showers measured at LOFAR

    CERN Document Server

    Nelles, A; Karskens, T; Krause, M; Buitink, S; Corstanje, A; Enriquez, J E; Erdmann, M; Falcke, H; Haungs, A; Hiller, R; Huege, T; Krause, R; Link, K; Norden, M J; Rachen, J P; Rossetto, L; Schellart, P; Scholten, O; Schröder, F G; ter Veen, S; Thoudam, S; Trinh, T N G; Weidenhaupt, K; Wijnholds, S J; Anderson, J; Bähren, L; Bell, M E; Bentum, M J; Best, P; Bonafede, A; Bregman, J; Brouw, W N; Bruüggen, M; Butcher, H R; Carbone, D; Ciardi, B; de Gasperin, F; Duscha, S; Eislöffel, J; Fallows, R A; Frieswijk, W; Garrett, M A; van Haarlem, M P; Heald, G; Hoeft, M; Horneffer, A; Iacobelli, M; Juette, E; Karastergiou, A; Kohler, J; Kondratiev, V I; Kuniyoshi, M; Kuper, G; van Leeuwen, J; Maat, P; McFadden, R; McKay-Bukowski, D; Orru, E; Paas, H; Pandey-Pommier, M; Pandey, V N; Pizzo, R; Polatidis, A G; Reich, W; Röttgering, H; Schwarz, D; Serylak, M; Sluman, J; Smirnov, O; Tasse, C; Toribio, M C; Vermeulen, R; van Weeren, R J; Wijers, R A M J; Wucknitz, O; Zarka, P

    2015-01-01

    Air showers induced by cosmic rays create nanosecond pulses detectable at radio frequencies. These pulses have been measured successfully in the past few years at the LOw- Frequency ARray (LOFAR) and are used to study the properties of cosmic rays. For a complete understanding of this phenomenon and the underlying physical processes, an absolute calibration of the detecting antenna system is needed. We present three approaches that were used to check and improve the antenna model of LOFAR and to provide an absolute calibration for air shower measurements. Two methods are based on calibrated reference sources and one on a calibration approach using the diffuse radio emission of the Galaxy, optimized for short data-sets. An accuracy of 35% in amplitude is reached. The absolute calibration is also compared to predictions from air shower simulations. These results are used to set an absolute energy scale for air shower measurements and can be used as a basis for an absolute scale for the measurement of astronomic...

  16. Absolute measurement of the DT primary neutron yield on the National Ignition Facility

    OpenAIRE

    Leeper R.J.; Bleuel D.L.; Frenje J.A.; Eckart M.J.; Hartouni E.; Kilkenny J.D.; Casey D.T.; Chandler G.A.; Cooper G.W.; Glebov V.Yu.; Hagmann C.; Johnson M.Gatu; Knauer J.P.; Knittel K.M.; Linden-Levy L.A.

    2013-01-01

    The measurement of the absolute neutron yield produced in inertial confinement fusion target experiments conducted on the National Ignition Facility (NIF) is essential in benchmarking progress towards the goal of achieving ignition on this facility. This paper describes three independent diagnostic techniques that have been developed to make accurate and precise DT neutron yield measurements on the NIF.

  17. Absolute measurement of the DT primary neutron yield on the National Ignition Facility

    International Nuclear Information System (INIS)

    The measurement of the absolute neutron yield produced in inertial confinement fusion target experiments conducted on the National Ignition Facility (NIF) is essential in benchmarking progress towards the goal of achieving ignition on this facility. This paper describes three independent diagnostic techniques that have been developed to make accurate and precise DT neutron yield measurements on the NIF. (authors)

  18. Absolute measurement of the DT primary neutron yield on the National Ignition Facility

    Directory of Open Access Journals (Sweden)

    Leeper R.J.

    2013-11-01

    Full Text Available The measurement of the absolute neutron yield produced in inertial confinement fusion target experiments conducted on the National Ignition Facility (NIF is essential in benchmarking progress towards the goal of achieving ignition on this facility. This paper describes three independent diagnostic techniques that have been developed to make accurate and precise DT neutron yield measurements on the NIF.

  19. Absolute determination of 75Se for international comparison of activity measurements

    International Nuclear Information System (INIS)

    An international intercomparison of absolute activity measurements of a solution of Se-75, organized by the Bureau International des Poids et Mesures, France, in 1992, has been carried out. The methodology and results are presented. Source preparation, experimental techniques and measurement system are described. (author). 2 refs

  20. Relative gravity measurement campaign during the 7th International Comparison of Absolute Gravimeters (2005).

    Czech Academy of Sciences Publication Activity Database

    Jiang, Z.; Becker, M.; Francis, O.; Palinkáš, V.; Jousset, P.; Kostelecký, J.; Dupont, F.; Lee, C. W.; Tsai, C. L.; Falk, R.; Wilmes, H.; Kopaev, A.; Ruess, D.; Ullrich, M.; Meurers, B.; Mrlina, Jan; Deroussi, S.; Métivier, L.; Pajot, G.; Pereira Dos Santos, F.; Van Ruymbeke, M.; Naslin, S.; Ferry, M.

    2009-01-01

    Ro?. 46, ?. 3 (2009), s. 214-226. ISSN 0026-1394 Institutional research plan: CEZ:AV0Z30120515 Keywords : absolute gravity measurements * relative gravity measurements * ICAG Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 1.634, year: 2009

  1. Measurement of statistical evidence on an absolute scale following thermodynamic principles

    CERN Document Server

    Vieland, V J; Hodge, S E; Seok, S -C

    2013-01-01

    Statistical analysis is used throughout biomedical research and elsewhere to assess strength of evidence. We have previously argued that typical outcome statistics (including p-values and maximum likelihood ratios) have poor measure-theoretic properties: they can erroneously indicate decreasing evidence as data supporting an hypothesis accumulate; and they are not amenable to calibration, necessary for meaningful comparison of evidence across different study designs, data types, and levels of analysis. We have also previously proposed that thermodynamic theory, which allowed for the first time derivation of an absolute measurement scale for temperature (T), could be used to derive an absolute scale for evidence (E). Here we present a novel thermodynamically-based framework in which measurement of E on an absolute scale, for which "one degree" always means the same thing, becomes possible for the first time. The new framework invites us to think about statistical analyses in terms of the flow of (evidential) i...

  2. International conventions for measuring radioactivity of building materials

    International Nuclear Information System (INIS)

    In buildings, whether civil or industrial, natural radioactivity always occurs at different degrees in the materials (main building materials, decorative materials). Concerns on radioactivity from building materials is unavoidable for human living and developing. As a member of WTO, China's measuring method of radioactivity for building materials, including radionuclides limitation for building materials, hazard evaluation system etc, should keep accordance with the international rules and conventions. (author)

  3. Measurement of absolute intensity of weak magnetic fields using rf biased SQUID

    International Nuclear Information System (INIS)

    A method to measure the absolute intensity of a weak magnetic field is described. A superconducting material was used as a sensor and the magnetization change was detected between the superconducting state and the normal state at the transition temperature. The magnetization change measured by a SQUID system was found to be proportional to the component of the absolute intensity of the magnetic field at the superconductor specimen parallel with the axis of the astatic pick up coils. A resolution of 10-5Oe was obtained. The practical limit of the resolution of this method is also discussed. (author)

  4. Direct frequency comb measurements of absolute optical frequencies and population transfer dynamics

    OpenAIRE

    Marian, Adela; Stowe, Matthew C.; Felinto, Daniel; Ye, * Jun

    2005-01-01

    A phase-stabilized femtosecond laser comb is directly used for high-resolution spectroscopy and absolute optical frequency measurements of one- and two-photon transitions in laser-cooled \\rb atoms. Absolute atomic transition frequencies, such as the 5S$_{1/2}$ F=2 \\ra 7S$_{1/2}$ F"=2 two-photon resonance measured at 788 794 768 921(44) kHz, are determined without \\textit{a priori} knowledge about their values. Detailed dynamics of population transfer driven by a sequence of ...

  5. A flowrate measurement method by counting of radioactive particles suspended in a liquid

    International Nuclear Information System (INIS)

    By external counting of fine #betta# emitting radioactive particles suspended in a liquid, the flowrate in a system of pipes can be measured. The study comprises three phases: 1. - The hydraulic validity of the method is demonstrated in laminar as well as in turbulent flow under certain conditions of particles size and density and of liquid viscosity. 2. - Radioactive labelling of microspheres of serumalbumin or ion exchange resins with indium 113m delivered by a generator Tin 113 ? Indium 113m. 3. - Counting with a scintillation detector: a method of threshold overstepping is experimented with a mechanical or electronic simulator; the statistical study of particle superposition under the detector enables a correction for the resulting counting losses to be proposed. The method provides absolute measurements, but is particularly suitable to measure relative flowrates in a hydraulic network. It can be continuous and does not perturb the flow and the network. The accuracy of the method is analysed in details

  6. Publication of measured values of radioactivity in food

    International Nuclear Information System (INIS)

    The radioactivity in food is recorded at 20 different measuring points in the Federal States, furthermore at one coordinating office of the Federal Government, and at a number of research institutes. Measurements are carried out permanently, particularly with regard to the relevant radionuclides such as Cesium 134 and Cesium 137. The measured values of the radioactive contamination in food are published by the Federal States for reasons of competence, and also by the Federal Government, in its summarizing reports ''Environmental radioactivity and radiation exposure.'' (orig./HSCH)

  7. Absolute Retinal Blood Flow Measurement With a Dual-Beam Doppler Optical Coherence Tomography

    OpenAIRE

    Dai, Cuixia; Liu, Xiaojing; Zhang, Hao F.; Puliafito, Carmen A.; Jiao, Shuliang

    2013-01-01

    A novel dual-beam Doppler OCT technique was developed for simultaneous in vivo measurement of the Doppler angle and, thus, the absolute retinal blood velocity and the retinal flow rate, without the influence of motion artifacts. The technique was successfully tested on humans.

  8. On the absolute measure of Beta activities; Sobre la medida absoluta de actividades Beta

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, C.; Jimenez Reynaldo, O.; Rodriguez Mayquez, E.

    1956-07-01

    A new method for absolute beta counting of solid samples is given. The measurements is made with an inside Geiger-Muller tube of new construction. The backscattering correction when using an infinite thick mounting is discussed and results for different materials given. (Author)

  9. Low geometry counter for the absolute measurement of the activity of alpha-emitting sources

    International Nuclear Information System (INIS)

    A low-geometry counter is described which allows the absolute determination of the activity for alpha-emitting sources. A Si implanted detector is used to obtain the spectrum of the sample. Two samples are measured with this counter and a 2 ? gridded ion chamber. The results an their uncertainties for both instruments are discussed. (Author)

  10. Results of radioactivity measurements on foodstuffs in Romania

    International Nuclear Information System (INIS)

    There are presented the results of gamma-spectrometric measurements performed between 1986-1995 on: milk and dairy products; meat and meat products; fish; wheat flour; fresh fruits and vegetables. The foodstuffs are sampled from some representative areas like: Bucharest, Bechet (affected by Kozloduj NPP, Bulgaria), Cernavoda, middle of Transylvania, Neamt. The radioactivity measurements are performed by high-resolution ?-ray spectrometry. There are identified and analysed mainly 134Cs, 137Cs, 40K and, sometimes, other radionuclides. There are pointed out: the constancy of natural radionuclides amounts; the drastic increasing in radioactive concentration in May 1986; the seasonal variation of radioactivity in some food items; the time - exponential diminution of radioactivity in 1991-1995; and the maximum permitted levels of radioactive contamination of foodstuffs following a nuclear accident. (author)

  11. New absolute distance measurement technique with a self-mixing interferometer

    Energy Technology Data Exchange (ETDEWEB)

    Guo Dongmei; Wang Ming [JiangSu Key Lab on opto-electronic Technology, School of Physical Science and Technology, Nanjing Normal University, 210097, Nanjing (China)

    2007-07-15

    A new compact self-aligned noncontact range finder is described. It uses the self-mixing effect inside a laser diode. Double modulation technique is proposed to improve the measurement accuracy. Wavelength modulation (WM) of the laser beam is obtained by modulating the injection current of the laser diode. Phase modulation (PM) of the laser beam is obtained by an electro-optic crystal (EOC) in the external cavity. Absolute distance of the external target is determined by Fourier analysis method. Experimental results show that an accuracy of {+-}0.3mm can be achieved for absolute distance ranging from 277mm to 477mm.

  12. Absolute Wavelength Calibration of the IDSII Spectrometer for Impurity Ion Velocity Measurements in the MST

    Science.gov (United States)

    Baltzer, M.; Craig, D.; den Hartog, D. J.; Nornberg, M. D.; MST Team

    2014-10-01

    The MST operates two Ion Doppler Spectrometers (IDS) for high time-resolution passive and active measurements of impurity ion emission. Absolutely calibrated measurements of flow are difficult because the spectrometers record data within 0.3 nm of the line of interest, and commercial calibration lamps do not produce lines in this narrow range . Four calibration methods were investigated. First, emission along the chord bisecting the poloidal plane was measured as it should have no time-averaged Doppler shift. Second, a calibrated CCD spectrometer and the IDSII were used to observe the same plasma from opposing sides so as to measure opposite Doppler shifts. The unshifted line is located halfway between the two opposing measurements. Third, the two fibers of the IDSI were positioned to take absolute flow measurements using opposing views. Substituting the IDSII for one of the IDSI fibers, absolute measurements of flow from the IDSI were used to calibrate the IDSII. Finally, an optical system was designed to filter an ultraviolet LED, providing a known wavelength source within the spectral range covered by the IDSII. The optical train is composed of an air-gapped etalon and fused silica lenses. The quality of calibration for each of these methods is analyzed and their results compared. Preliminary impurity ion velocity measurements are shown. This work has been supported by the US DOE and the NSF.

  13. Radioactivity measurements for the ERMES project at the STELLA facility

    Science.gov (United States)

    Laubenstein, M.; Plastino, W.; Aprili, P.; Balata, M.; Bella, F.; Gallese, B.; Ioannucci, L.; Nisi, S.

    2012-04-01

    STELLA (SubTErranean Low Level Assay) is the ultra low background facility of the Gran Sasso National Laboratories (L.N.G.S.) in Italy. It is mainly devoted to material screening and rare events physics due to its very low radioactive background. Nevertheless, also environmental samples are measured within the collaboration with the ERMES (Environmental Radioactivity Monitoring for Earth Sciences) project. After a short description of the facility some on-going applications within the ERMES project will be briefly presented. The usefulness of doing environmental radioactivity measurements in a deep underground laboratory will be shortly discussed.

  14. Radioactivity measurements for the ERMES project at the STELLA facility

    Directory of Open Access Journals (Sweden)

    Gallese B.

    2012-04-01

    Full Text Available STELLA (SubTErranean Low Level Assay is the ultra low background facility of the Gran Sasso National Laboratories (L.N.G.S. in Italy. It is mainly devoted to material screening and rare events physics due to its very low radioactive background. Nevertheless, also environmental samples are measured within the collaboration with the ERMES (Environmental Radioactivity Monitoring for Earth Sciences project. After a short description of the facility some on-going applications within the ERMES project will be briefly presented. The usefulness of doing environmental radioactivity measurements in a deep underground laboratory will be shortly discussed.

  15. A novel method for the absolute fluorescence yield measurement by AIRFLY

    Energy Technology Data Exchange (ETDEWEB)

    Ave, M. [University of Chicago, Enrico Fermi Institute, 5640 S Ellis Ave., Chicago, IL 60637 (United States); Bohacova, M. [Institute of Physics of the Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Praha 8 (Czech Republic)], E-mail: bohacova@fzu.cz; Buonomo, B. [Laboratori Nazionali di Frascati dell' INFN, INFN, Sezione di Frascati, Via Enrico Fermi 40, Frascati, Rome 00044 (Italy); Busca, N.; Cazon, L. [University of Chicago, Enrico Fermi Institute, 5640 S Ellis Ave., Chicago, IL 60637 (United States); Chemerisov, S.D.; Conde, M.E.; Crowell, R.A. [Argonne National Laboratory, Argonne, IL 60439 (United States); Di Carlo, P. [Dipartimento di Fisica dell' Universita de l' Aquila and INFN, Via Vetoio, I-67010 Coppito, Aquila (Italy); Di Giulio, C. [Dipartimento di Fisica dell' Universita di Roma Tor Vergata and Sezione INFN, Via della Ricerca Scientifica, I-00133 Rma (Italy); Doubrava, M. [Czech Technical University, Technicka 4, 16607 Praha 6 (Czech Republic); Esposito, A. [Laboratori Nazionali di Frascati dell' INFN, INFN, Sezione di Frascati, Via Enrico Fermi 40, Frascati, Rome 00044 (Italy); Facal, P. [Departmento de Fi' sica de Parti' culas, Campus Sur, Universidad, E-15782, Santiago de Compostela (Spain); Franchini, F.J. [Argonne National Laboratory, Argonne, IL 60439 (United States); Hoerandel, J.R. [Universitaet Karlsruhe (Thailand), Institut fuer Experimentelle Kernphysik (IEKP), Postfach 6980, D-76128 Karlsruhe (Germany); Hrabovsky, M. [Institute of Physics of the Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Praha 8 (Czech Republic); Iarlori, M. [Dipartimento di Fisica dell' Universita de l' Aquila and INFN, Via Vetoio, I-67010 Coppito, Aquila (Italy); Kasprzyk, T.E. [Argonne National Laboratory, Argonne, IL 60439 (United States); Keilhauer, B. [Universitaet Karlsruhe (Thailand), Institut fuer Experimentelle Kernphysik (IEKP), Postfach 6980, D-76128 Karlsruhe (Germany)] (and others)

    2008-11-21

    One of the goals of the AIRFLY (AIR FLuorescence Yield) experiment is to measure the absolute fluorescence yield induced by electrons in air to better than 10% precision. We introduce a new technique for measurement of the absolute fluorescence yield of the 337 nm line that has the advantage of reducing the systematic uncertainty due to the detector calibration. The principle is to compare the measured fluorescence yield to a well known process-the Cherenkov emission. Preliminary measurements taken in the BFT (Beam Test Facility) in Frascati, Italy with 350 MeV electrons are presented. Beam tests in the Argonne Wakefield Accelerator at the Argonne National Laboratory, USA with 14 MeV electrons have also shown that this technique can be applied at lower energies.

  16. A novel method for the absolute fluorescence yield measurement by AIRFLY

    International Nuclear Information System (INIS)

    One of the goals of the AIRFLY (AIR FLuorescence Yield) experiment is to measure the absolute fluorescence yield induced by electrons in air to better than 10% precision. We introduce a new technique for measurement of the absolute fluorescence yield of the 337 nm line that has the advantage of reducing the systematic uncertainty due to the detector calibration. The principle is to compare the measured fluorescence yield to a well known process-the Cherenkov emission. Preliminary measurements taken in the BFT (Beam Test Facility) in Frascati, Italy with 350 MeV electrons are presented. Beam tests in the Argonne Wakefield Accelerator at the Argonne National Laboratory, USA with 14 MeV electrons have also shown that this technique can be applied at lower energies.

  17. Production and trapping of carbon clusters for absolute mass measurements at ISOLTRAP

    CERN Document Server

    Scheidenberger, C; Herfurth, F; Kellerbauer, A G; Kluge, H J; Koizumi, M; Schwarz, S; Schweikhard, L

    2002-01-01

    Singly-charged carbon clusters C/sub n//sup +/ (n >or= 1) have been produced by laser-induced desorption and fragmentation of C/sub 60/ fullerenes and have been injected into and stored in the Penning trap system of the ISOLTRAP mass spectrometer at ISOLDE/CERN. The present study is the first step to extend the until now direct mass measurements at ISOLTRAP to absolute mass measurements by using clusters of /sup 12/C. (10 refs).

  18. Absolute equation of state measurements of iron using laser driven shocks

    International Nuclear Information System (INIS)

    First absolute equation of state measurements obtained for iron with laser driven shock waves are presented. The shock velocity and the free surface velocity of compressed iron have been simultaneously measured by using a VISAR diagnostic, and step targets. The pressure range 1-8 Mbar has been investigated, which is directly relevant to planetary physics. The experiments have been performed at the Laboratoire pour l'Utilisation des Lasers Intenses of the Ecole Polytechnique

  19. ArtDeco: A beam deconvolution code for absolute CMB measurements

    OpenAIRE

    Keihänen, Elina; Reinecke, Martin

    2012-01-01

    We present a method for beam deconvolution for cosmic microwave background (CMB) anisotropy measurements. The code takes as input the time-ordered data, along with the corresponding detector pointings and known beam shapes, and produces as output the harmonic a_Tlm, a_Elm, and a_Blm coefficients of the observed sky. From these one can further construct temperature and Q and U polarisation maps. The method is applicable to absolute CMB measurements with wide sky coverage, and...

  20. White-light scanning interferometer for absolute nano-scale gap thickness measurement

    OpenAIRE

    Xu, Zhiguang; Shilpiekandula, Vijay; Youcef-toumi, Kamal; Yoon, Soon Fatt

    2009-01-01

    A special configuration of white-light scanning interferometer is described for measuring the absolute air gap thickness between two planar plates brought into close proximity. The measured gap is not located in any interference arm of the interferometer, but acts as an amplitude-and-phase modulator of the light source. Compared with the common white-light interferometer our approach avoids the influence of the chromatic dispersion of the planar plates on the gap thickness quantification. It ...

  1. Polarized H- Jet Polarimeter For Absolute Proton Polarization Measurements in RHIC

    International Nuclear Information System (INIS)

    Status of the H-jet polarimeter development is reviewed. A number of design issues are discussed including vacuum system, integration into the RHIC storage ring, scattering chamber, and uniform vertical holding field magnet design. The absolute proton polarization of the atomic hydrogen-jet target will be measured to 3% accuracy by a Breit- systematic error contribution to the jet-target polarization measurements is also discussed

  2. Absolute calibration of the neutron yield measurement on JT-60 Upgrade

    International Nuclear Information System (INIS)

    Absolutely calibrated measurements of the neutron yield are important for the evaluation of the plasma performance such as the fusion gain Q in DD operating tokamaks. Total neutron yield is measured with 235U and 238U fission chambers and 3He proportional counters in JT-60 Upgrade. The in situ calibration was performed by moving the 252Cf neutron source toroidally through the JT-60 vacuum vessel. Detection efficiencies of three 235U and two 3He detectors were measured for 92 locations of the neutron point source in toroidal scans at two different major radii. The total detection efficiency for the torus neutron source was obtained by averaging the point efficiencies over the whole toroidal angle. The uncertainty of the resulting absolute plasma neutron source calibration is estimated to be ± 10%. (author)

  3. Measurement of absolute Al concentration in AlxGa1-xAs

    International Nuclear Information System (INIS)

    A technique has been developed to measure the absolute Al concentration x in AlxGa1-xAs. The technique involves simultaneous measurements of the 27Al(p,?)28Si resonant nuclear reaction and Rutherford backscattering (RBS), and comparisons with an AlAs reference sample. A detailed description of the experimental procedure is given. Samples analyzed in this study were prepared by LPE and MOVPE growth on GaAs substrates, with expitaxial layer thicknesses in the range 1-3 ?m and Al concentrations in the range 0.10< x<0.85. Measurements of x with an absolute error <0.02 were obtained. Factors limiting the precision obtainable with this technique are discussed. (orig.)

  4. A novel absolute measurement for the low-frequency figure correction of aspheric surfaces

    Science.gov (United States)

    Lin, Wei-Cheng; Chang, Shenq-Tsong; Ho, Cheng-Fang; Kuo, Ching-Hsiang; Chung, Chien-Kai; Hsu, Wei-Yao; Tseng, Shih-Feng; Sung, Cheng-Kuo

    2015-07-01

    This study proposes an absolute measurement method with a computer-generated hologram (CGHs) to assist the identification of manufacturing form error, and gravity and mounting resulted distortions for a 300 mm aspherical mirror. This method adopts the frequency of peaks and valleys of each Zernike coefficient grabbed by the measurement with various orientations of the mirror in horizontal optical-axis configuration. In addition, the rotational-symmetric aberration (spherical aberration) is calibrated with random ball test method. According to the measured absolute surface figure, a high accuracy aspherical surface with peak to valley (P-V) value of 1/8 wave @ 632.8 nm was fabricated after surface figure correction with the reconstructed error map.

  5. High-precision gravity measurements using absolute and relative gravimeters at Mount Etna (Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Ciro Del Negro

    2011-12-01

    Full Text Available Accurate detection of time gravity changes attributable to the dynamics of volcanoes requires high-precision gravity measurements. With the aim of improving the quality of data from the Mount Etna gravity network, we used both absolute and relative gravimeters in a hybrid method. In this report, some of the techniques for gravity surveys are reviewed, and the results related to each method are compared. We show how the total uncertainty estimated for the gravity measurements performed with this combined use of absolute and relative gravimeters is roughly comparable to that calculated when the measurements are acquired using only relative gravimeters (the traditional method. However, the data highlight how the hybrid approach improves the measurement capabilities for surveying the Mount Etna volcanic area. This approach enhances the accuracy of the data, and then of the four-dimensional surveying, which minimizes ambiguities inherent in the gravity measurements. As a case study, we refer to two gravity datasets acquired in 2005 and 2010 from the western part of the Etna volcano, which included five absolute and 13 relative stations of the Etna gravity network.

  6. High-precision Absolute Distance Measurements over a Long Range Based on Two Optoelectronic Oscillators

    CERN Document Server

    Yu, Jinlong; Miao, Wang; Zhu, Jigui; Sun, Bin; Wang, Wenrui; Hu, Hao

    2012-01-01

    Absolute distance measurement (ADM) over a long range has been studied intensely over the last several decades, due to its important applications in large-scale manufacturing and outer space explorations [1-5]. Traditional absolute distance measurements utilize detection of time-of-flight information, detection of phase shift, or a combination of the two [6-17]. In this paper, we present a novel scheme for high-precision ADM over a long range based on frequency detection by using two optoelectronic oscillators (OEO) to convert distance information to frequency information. By taking advantage of accumulative magnification theory, the absolute error of the measured distance is magnified by about 2*10E5 times, which makes the precision of the measured distance significantly improved. In our experiments, the maximum error is 1.5 um at the emulated ~6 km distance, including the drift error of about 1 um in the air path due to the change in environmental conditions. In addition, the measurable distance using this ...

  7. Laser induced deflection technique for absolute thin film absorption measurement: optimized concepts and experimental results.

    Science.gov (United States)

    Mühlig, Christian; Kufert, Siegfried; Bublitz, Simon; Speck, Uwe

    2011-03-20

    Using experimental results and numerical simulations, two measuring concepts of the laser induced deflection (LID) technique are introduced and optimized for absolute thin film absorption measurements from deep ultraviolet to IR wavelengths. For transparent optical coatings, a particular probe beam deflection direction allows the absorption measurement with virtually no influence of the substrate absorption, yielding improved accuracy compared to the common techniques of separating bulk and coating absorption. For high-reflection coatings, where substrate absorption contributions are negligible, a different probe beam deflection is chosen to achieve a better signal-to-noise ratio. Various experimental results for the two different measurement concepts are presented. PMID:21460979

  8. A system and methodologies for absolute QE measurements from the vacuum ultraviolet through the NIR

    CERN Document Server

    Jacquot, Blake C; Hoenk, Michael E; Greer, Frank; Jones, Todd J; Nikzad, Shouleh

    2011-01-01

    In this paper we present our system design and methodology for making absolute quantum efficiency (QE) measurements through the vacuum ultraviolet (VUV) and verify the system with delta-doped silicon CCDs. Delta-doped detectors provide an excellent platform to validate measurements through the VUV due to their enhanced UV response. The requirements for measuring QE through the VUV are more strenuous than measurements in the near UV and necessitate, among other things, the use of a vacuum monochromator, good dewar chamber vacuum to prevent on-chip condensation, and more stringent handling requirements.

  9. Radioactivity measuring system of labelled biopolymers

    International Nuclear Information System (INIS)

    System for determining the radioactivity of labelled biopolymers, comprising a bank of containers filled with aqueous solutions of biological samples containing biopolymers. This system features an electric drive to move the bank of containers step by step; a device for the acid precipitation of the biopolymers which sends determined amounts of co-precipitant and diatom suspension in an acid solution to the containers containing a biological sample; a system for taking precipitated samples from the containers; a system for filtering the precipitated biopolymers carrying out successive filterings; placing the deposit into suspension; dissolving the biopolymers and sending the labelled mixture labelled by the scintillation labeller to the detection chamber

  10. Absolute measurements of electron impact excitation cross-sections of atoms using cavity ringdown spectroscopy

    International Nuclear Information System (INIS)

    A new method of using cavity ringdown spectroscopy (CRDS) technique to measure apparent electron impact excitation cross-sections (EIECS) for different energy levels of an atom is described. The method involves measurements of absolute population densities of the energy levels in concern using the high sensitivity CRDS, leading to an analytical expression of EIECS as a function of the population densities. Determination of EIECS in this method does not require an external calibration. The proposed method is validated by determining EIECS of the metastable levels of Hg (6s6p 3P0) and Ne (2p53s 3P2), and the results are in good agreement with the cross-sections reported in the literature. The population densities in both cases were extracted from the published data. This method exhibits promising potential for absolute measurements of EIECS of metastable energy levels. - Highlights: • Cavity ringdown spectroscopy for electron impact excitation cross-sections. • Measurements of absolute population densities of the energy levels. • An analytical expression of electron impact excitation cross-section. • The method is validated by two cases (the metastable Hg and the metastable Ne atoms)

  11. Radioactivity measurements for the ERMES project at the STELLA facility

    OpenAIRE

    Gallese B.; Bella F.; Balata M.; Aprili P.; Plastino W.; Laubenstein M.; Ioannucci L.; Nisi S.

    2012-01-01

    STELLA (SubTErranean Low Level Assay) is the ultra low background facility of the Gran Sasso National Laboratories (L.N.G.S.) in Italy. It is mainly devoted to material screening and rare events physics due to its very low radioactive background. Nevertheless, also environmental samples are measured within the collaboration with the ERMES (Environmental Radioactivity Monitoring for Earth Sciences) project. After a short description of the facility some on-going applications within the ERMES p...

  12. Hyperspectral interferometry for single-shot absolute measurement of two-dimensional optical path distributions

    International Nuclear Information System (INIS)

    We propose a method that we call hyperspectral interferometry (HSI) to resolve the 2? phase unwrapping problem in the analysis of interferograms recorded with a narrow-band light source. By using a broadband light source and a hyperspectral imaging system, a set of interferograms at different wave numbers are recorded simultaneously on a high resolution image sensor. These are then assembled to form a three-dimensional intensity distribution. By Fourier transformation along the wave number axis, an absolute optical path difference is obtained for each pixel independently of the other pixels in the field of view. As a result, interferograms with spatially distinct regions are analysed as easily as continuous ones. The approach is illustrated with a HSI system to measure 3D profiles of optically smooth or rough surfaces. Compared to existing profilometers able to measure absolute path differences, the single-shot nature of the approach provides greater immunity from environmental disturbance

  13. Hyperspectral interferometry for single-shot absolute measurement of 3-D shape and displacement fields

    Directory of Open Access Journals (Sweden)

    Ruiz P. D.

    2010-06-01

    Full Text Available We propose a method that we call Hyperspectral Interferometry (HSI to resolve the 2? phase unwrapping problem in the analysis of interferograms recorded with a narrow-band light source. By using a broad-band light source and hyperspectral imaging system, a set of interferograms at different wavenumbers are recorded simultaneously on a high resolution image sensor. These are then assembled to form a three-dimensional intensity distribution. By Fourier transformation along the wavenumber axis, an absolute optical path difference is obtained for each pixel independently of the other pixels in the field of view. As a result, interferograms with spatially distinct regions are analysed as easily as continuous ones. The approach is illustrated with a HSI system to measure 3-D profiles of optically smooth or rough surfaces. Compared to existing profilometers able to measure absolute path differences, the single shot nature of the approach provides greater immunity from environmental disturbance.

  14. Experimental feasibility of the airborne measurement of absolute oil fluorescence spectral conversion efficiency

    International Nuclear Information System (INIS)

    Recent theoretical work has shown conceptual feasibility for the airborne measurement of the absolute oil fluorescence spectral conversion efficiency (AOFSCE) of crude and refined petroleum oils on the ocean surface without a priori knowledge of the film thickness. Reported herein are airborne lidar oil spill experiments conducted to determine the practical feasibility of the AOFSCE computational model. The results of these investigations demonstrate that the AOFSCE model is practical over a considerable range of oil film thicknesses provided the fluorescence efficiency of the oil does not approach the minimum detection sensitivity limitations of the lidar system. Separate airborne lidar experiments to demonstrate measurement of the water column Raman conversion efficiency have also been conducted to ascertain the ultimate feasibility of converting such relative oil fluorescence to absolute values. The AOFSCE model shows excellent potential, however, further airborne water column Raman conversion efficiency experiments with improved temporal or depth-resolved waveform calibration and software deconvolution techniques are required for final feasibility determination

  15. A measurement of the absolute flux of cosmic-ray electrons

    Science.gov (United States)

    Golden, R. L.; Mauger, B. G.; Badhwar, G. D.; Daniel, R. R.; Lacy, J. L.; Stephens, S. A.; Zipse, J. E.

    1984-01-01

    A balloon-borne superconducting magnet spectrometer was used to measure the absolute flux of cosmic-ray electrons. The instrument consisted of a gas Cerenkov detector, a momentum spectrometer, and a lead-scintillator shower counter. In order to determine electron flux in the interstellar medium, observed fluxes for energy loss in the atmosphere and the payload were corrected, taking into account solar modulation effects and bremsstrahlung energy losses. Fluxes were measured at an average atmospheric depth of 5.8 g/sq cm, and the solar modulation was 300 MeV. A cosmic-ray electron flux of 367 E to the exp(3.15 + or -0.2) per sq m/sr s GeV was obtained in the energy range 4.5-63.5 GeV. The uncertainty of the absolute (electron-positron) flux was 10 percent. A summary of the electron data is given in a table.

  16. Geometry of expanding absolutely continuous invariant measures and the liftability problem

    International Nuclear Information System (INIS)

    We consider a quite broad class of maps on compact manifolds of arbitrary dimension possibly admitting critical points, discontinuities and singularities. Under some mild nondegeneracy assumptions we show that f admits an induced Gibbs-Markov map with integrable inducing times if and only if it has an ergodic invariant probability measure which is absolutely continuous with respect to the Riemannian volume and has all Lyapunov exponents positive. (author)

  17. Absolute Bunch Length Measurements at the ALS by Incoherent Synchrotron Radiation Fluctuation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Filippetto, D.; /Frascati; Sannibale, F.; Zolotorev, Max Samuil; /LBL, Berkeley; Stupakov, G.V.; /SLAC

    2008-01-24

    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 tested a simple scheme based on this principle that allows for the absolute measurement of the bunch length. A description of the method and the experimental results are presented.

  18. Absolute energy measurement of heavy ion beams using a resonant time-of-flight system

    International Nuclear Information System (INIS)

    A resonant time-of-flight measurement system has been put into operation at the ATLAS facility for the determination of the energy of heavy ion beams. The system provides continuous, nondestructive monitoring of the beam energy. The system provides relative energy determination with a precision of ?E/E ? 10-4. Absolute energy is determined to an accuracy of 10-3. A variety of beam tests have been performed to study the properties of the system. (orig.)

  19. Scanning Laser Polarimetry for Measurement of Retinal Nerve Fiber Layer in Absolute, Advanced and Early Glaucoma

    OpenAIRE

    Jen-Chia Tsai; Hsueh-Wen Chang; Mei-Ching Teng; Pei-Wen Lin; Ing-Chou Lai

    2006-01-01

    Background: To detect differences in retinal nerve fiber layer (RNFL) measurements inabsolute, advanced and early glaucoma with scanning laser polarimetry (TheNerve Fiber Analyzer GDx), and to assess the usefulness and limitations ofthis technique for longitudinal follow-up of glaucoma patients.Methods: This is a prospective, cross-sectional study. Twenty-one eyes of 21 patientswith absolute glaucoma, twenty-six eyes of 26 patients with advanced glaucomaand twenty-four eyes of 24 patients wit...

  20. ABSOLUTE BUNCH LENGTH MEASUREMENTS AT THE ALS BY INCOHERENT SYNCHROTRON RADIATION FLUCTUATION ANALYSIS

    International Nuclear Information System (INIS)

    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 tested a simple scheme based on this principle that allows for the absolute measurement of the bunch length. A description of the method and the experimental results are presented

  1. Absolute measurement of the ultrafast nonlinear electronic and rovibrational response in H$_2$ and D$_2$

    CERN Document Server

    Wahlstrand, J K; Cheng, Y -H; Palastro, J P; Milchberg, H M

    2015-01-01

    The electronic, rotational, and vibrational components of the ultrafast optical nonlinearity in H$_2$ and D$_2$ are measured directly and absolutely at intensities up to the ionization threshold of $\\sim$10$^{14}$ W/cm$^2$. As the most basic nonlinear interactions of the simplest molecules exposed to high fields, these results constitute a benchmark for high field laser-matter theory and simulation.

  2. Comment on "Measurement of the speed-of-light perturbation of free-fall absolute gravimeters"

    CERN Document Server

    Nagornyi, V D

    2014-01-01

    The paper (Rothleitner et al. 2014 Metrologia 51, L9) reports on the measurement of the speed-of-light perturbation in absolute gravimeters. The conclusion that the perturbation reaches only 2/3 of the commonly accepted value violates the fundamental limitation on the maximum speed of information transfer. The conclusion was deluded by unaccounted parasitic perturbations, some of which are obvious from the report.

  3. Precise Measurement of the Absolute Yield of Fluorescence Photons in Atmospheric Gases

    OpenAIRE

    AIRFLY Collaboration; Ave, M.; Bohá?ová, M.; Daumiller, K.; Di Carlo, P.; Di Giulio, C.; Luis, P. Facal San; Gonzales, D.; Hojvat, C.; Hörandel, J. R.; Hrabovský, M.; Iarlori, M.; B. Keilhauer; Klages, H.; Kleifges, M.

    2011-01-01

    We have performed a measurement of the absolute yield of fluorescence photons at the Fermilab Test Beam. A systematic uncertainty at 5% level was achieved by the use of Cherenkov radiation as a reference calibration light source. A cross-check was performed by an independent calibration using a laser light source. A significant improvement on the energy scale uncertainty of Ultra-High Energy Cosmic Rays is expected.

  4. Precise measurement of the absolute yield of fluorescence photons in atmospheric gases

    Energy Technology Data Exchange (ETDEWEB)

    Ave, M. [Karlsruhe Institute of Technology, IK, Postfach 6980, D - 76021 Karlsruhe (Germany); Bohacova, M. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Institute of Physics of the Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-182 21 Praha 8 (Czech Republic); Daumiller, K. [Karlsruhe Institute of Technology, IK, Postfach 6980, D - 76021 Karlsruhe (Germany); Di Carlo, P. [Dipartimento di Fisica dell' Universita de l' Aquila and INFN, Via Vetoio, I-67010 Coppito, Aquila (Italy); Di Giulio, C. [Dipartimento di Fisica dell' Universita di Roma Tor Vergata and Sezione INFN, Via della Ricerca Scientifica, I-00133 Roma (Italy); Facal San Luis, Pedro, E-mail: facal@kicp.uchicago.edu [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Gonzales, D. [Karlsruhe Institute of Technology, IEKP, Postfach 3640, D - 76021 Karlsruhe (Germany); Hojvat, C. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Hoerandel, J.R. [IMAPP, Radboud University Nijmegen, 6500 GL Nijmegen (Netherlands); Hrabovsky, M. [Palacky University, RCATM, Olomuc (Czech Republic); Iarlori, M. [Dipartimento di Fisica dell' Universita de l' Aquila and INFN, Via Vetoio, I-67010 Coppito, Aquila (Italy); Keilhauer, B.; Klages, H. [Karlsruhe Institute of Technology, IK, Postfach 6980, D - 76021 Karlsruhe (Germany); Kleifges, M. [Karlsruhe Institute of Technology, IPE, Postfach 3640, D - 76021 Karlsruhe (Germany); Kuehn, F. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Monasor, M. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Nozka, L.; Palatka, M. [Institute of Physics of the Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-182 21 Praha 8 (Czech Republic)

    2011-03-15

    We have performed a measurement of the absolute yield of fluorescence photons at the Fermilab Test Beam. A systematic uncertainty at 5% level was achieved by the use of Cherenkov radiation as a reference calibration light source. A cross-check was performed by an independent calibration using a laser light source. A significant improvement on the energy scale uncertainty of Ultra-High Energy Cosmic Rays is expected.

  5. Measurement of Absolute Arterial Cerebral Blood Volume in Human Brain Without Using a Contrast Agent

    OpenAIRE

    Hua, Jun; QIN, Qin; Pekar, James J.; Van Zijl, Peter C.M.

    2011-01-01

    Arterial cerebral blood volume (CBVa) is a vital indicator of tissue perfusion and vascular reactivity. We extended the recently developed inflow vascular-space-occupancy (iVASO) MRI technique, which uses spatially selective inversion to suppress the signal from blood flowing into a slice, with a control scan to measure absolute CBVa using CSF for signal normalization. Images were acquired at multiple blood nulling times to account for the heterogeneity of arterial transit times across the br...

  6. Measurement of the Absolute np Scattering Differential Cross Section at 194 MeV

    CERN Document Server

    Sarsour, M; Planinic, M; Vigdor, S E; Allgower, C; Bergenwall, B; Blomgren, J; Hossbach, T; Jacobs, W W; Johansson, C; Klug, J; Klyachko, A V; Nadel-Turonski, P; Nilsson, L; Olsson, N; Pomp, S; Rapaport, J; Rinckel, T; Stephenson, E J; Tippawan, U; Wissink, S W; Zhou, Y

    2004-01-01

    We describe a double-scattering experiment with a novel tagged neutron beam to measure differential cross sections for np back-scattering to better than 2% absolute precision. The measurement focuses on angles and energies where the cross section magnitude and angle-dependence constrain the charged pion-nucleon coupling constant, but existing data show serious discrepancies among themselves and with energy-dependent partial wave analyses (PWA). The present results are in good accord with the PWA, but deviate systematically from other recent measurements.

  7. Absolute measurement of the responses of small lithium glass scintillators to gamma radiation

    International Nuclear Information System (INIS)

    The absolute scintillation efficiency and intrinsic resolution of lithium glass scintillators for electron excitation have been determined over a range of electron energies, lithium concentrations and lithium enrichments. Measurements of these response characteristics form part of a study on the possible use of such glasses for the determination of tritium breeding in fusion reactor blanket experiments. The measurements were undertaken to establish a basis for extracting the information relating to tritium production reactions from the background signals induced within the glass scintillators by the neutron/gamma fields of a fusion reactor blanket. Criteria for the selection of glasses most suitable for tritium breeding measurements are discussed in tems of their observed responses

  8. Radiative lifetimes, branching ratios and absolute transition probabilities of atomic uranium by delayed photoionization measurements

    Science.gov (United States)

    Mandal, P. K.; Das, R. C.; Seema, A. U.; Sahoo, A. C.; Shah, M. L.; Pulhani, A. K.; Manohar, K. G.; Dev, Vas

    2014-08-01

    Radiative lifetimes of ten even-parity energy levels of atomic uranium in the 15,500-19,000 cm-1 region and branching ratios of six transitions originating either from ground level (5L{6/o}) or from lowest metastable level (5K{5/o}) at 620.32 cm-1 are measured employing three-step delayed photoionization technique. The lifetimes of five energy levels and branching ratios of five transitions are measured for the first time. By combining the experimentally measured values of radiative lifetimes and branching ratios, we have determined the absolute transition probabilities of six transitions of uranium and compared with those previously reported in the literature.

  9. LHCb: A novel method for an absolute luminosity measurement at LHCb using beam-gas imaging

    CERN Multimedia

    Barschel, C

    2013-01-01

    A novel technique to measure the absolute luminosity at the Large Hadron Collider (LHC) using beam-gas interactions has been successfully used in the LHCb experiment. A gas injection device (SMOG) has been installed in the LHCb experiment to increase the pressure around the interaction point during dedicated fills. The Beam Gas Imaging method (BGI) has now the potential to surpass the accuracy of the commonly used van der Meer scan method (VDM). This poster presents the principles of the Beam Gas Imaging method used to measure the beam overlap integral. Furthermore the gas injection increased the accuracy measurement of the so-called ghost charges and also intensities per bunch.

  10. Measurements with radioactive beams at ATLAS.

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K. E.

    1998-08-06

    Reactions of interest to nuclear astrophysics have been studied with radioactive beams at the ATLAS accelerator. Using a modified ISOL technique, beams of {sup 18}F (T{sub 1/2} = 110 min) and {sup 56}Ni (T{sub 1/2} = 6.1d) were produced and the reactions {sup 18}F(p,{alpha}){sup 15}O, {sup 18}F(p,{gamma}){sup 19}Ne, and {sup 56}Ni(d,p){sup 57}Ni have been investigated. The results indicate that the {sup 18}F(p,{gamma}) route is a small contributor to the breakout from the hot CNO cycle into the rp process, while the {sup 56}Ni(p,{gamma}){sup 57}Cu rate is about ten times larger than previously assumed.

  11. 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'.

  12. Measurement of total body radioactivity in man

    International Nuclear Information System (INIS)

    Techniques for the determination of whole-body radioactivity in man using uncollimated NaI(Tl) detectors have been studied. Geometrical effects and photon attenuation effects due to the different shapes of humans as well as due to varying in-vivo radioactivity distributions have been evaluated particularly for scanning-bed geometries and the chair geometry. Theoretically it is shown that the attenuation effects are generally dominating, for full-energy-peak pulse-range methods. For the application in radiation protection a cheap and simple chair-geometry unit has been constructed and used at various places distantly from the home-laboratory, for studies of body activity of Cs-137 in northern Sweden. High body activities were found particularly in reindeer-breeding Lapps. The elimination rate of Cs-137 in man was studied in the stationary whole-body counter in Lund as well as with the field-system. For the study of the performances at low and high photon energies clinical applications of methods for gastro-intestinal absorption of vitamin B12 (Co-57; 122 keV) and total body potassium determination (K-40; 1.46 MeV, K-42; 1.52 MeV) have been evaluated. Theoretical and experimental results as well as experiences of applications in radiation protection and medicine show that the scanning-bed geometry effectively evens out redistributional effects. For optimum results, however, scatter-energy pulse-ranges rather than full-energy-peak ranges should be used. (Auth.)

  13. Measurement of the absolute energy scale of MINOS and background measurements in NEMO-3

    International Nuclear Information System (INIS)

    MINOS (Main Injector Neutrino Oscillation Search) is an experiment currently running in the US. A beam of neutrinos is created at Fermilab, Chicago, measured in the 1 kiloton 'Near Detector' and then travels 730 km to the 5 kiloton 'Far Detector' in the Soudan Mine, Minnesota. In the intervening time, it is hoped that some of these neutrinos will change from one flavor to another. If this is observed, it is strong evidence for neutrino oscillations, the parameters of which can be measured to 10%. The MINOS experiment is a large project with a huge number of technical issues. Many aspects of the experiment were tested several years before the main experiment itself began to run, by employing a scaled down version of the detectors, known as the Calibration Detector (CalDet). This was placed in a test-beam at CERN and extensively studied, the data from which is analyzed in this thesis. In this thesis, photomultiplier tube crosstalk is discussed, a phenomenon which generates false signals in the MINOS detectors. It is studied and an algorithm presented to enable its removal. Particle identification via various methods at CalDet is also described. Various pieces of hardware are available to assist with this, and a comparison is made to software techniques which are used at the larger MINOS detectors. A study of the CalDet beamline simulation is carried out and the discrepancies with data highlighted and explained. Finally, muon energy loss in CalDet is investigated. A comparison is made between published data and the observed data. NEMO-3 is an experiment that has been running for soe tie in the Frejus tunnel between France and italy. It is a 0??? experiment, hoping to show that the neutrino is a Majorana particle and set limits on its mass. This experiment, like every, has backgrounds. The dangerous background signals that arise from the radioactive decay of Uranium and Thorium are discussed in this thesis, specifically the measurement of the quantity of 208Tl and 214Bi in the source foils of the detector. This is achieved by using Monte Carlo simulations of the contaminants behavior in the detector, developing cuts on these events and applying them to the dataset.

  14. Scanning Laser Polarimetry for Measurement of Retinal Nerve Fiber Layer in Absolute, Advanced and Early Glaucoma

    Directory of Open Access Journals (Sweden)

    Jen-Chia Tsai

    2006-04-01

    Full Text Available Background: To detect differences in retinal nerve fiber layer (RNFL measurements inabsolute, advanced and early glaucoma with scanning laser polarimetry (TheNerve Fiber Analyzer GDx, and to assess the usefulness and limitations ofthis technique for longitudinal follow-up of glaucoma patients.Methods: This is a prospective, cross-sectional study. Twenty-one eyes of 21 patientswith absolute glaucoma, twenty-six eyes of 26 patients with advanced glaucomaand twenty-four eyes of 24 patients with early glaucoma were imagedusing scanning laser polarimetry. The twelve standard GDx measurementparameters were compared using ANOVA (analysis of variance and theTukey test.Results: No significant differences were demonstrated for any of the twelve GDxmeasurement parameters between absolute and advanced glaucoma cases.There were significant differences for some GDx parameters, including theGDx number (p < 0.0001 superior ratio (p < 0.0001, inferior ratio (p <0.0001, superior/nasal ratio (p < 0.0001, maximum modulation (p <0.0001, ellipse modulation (p < 0.0001 and inferior average (p = 0.001between early and advanced glaucoma, and, between early and absoluteglaucoma. Significant differences were demonstrated for the superior average(p = 0.01 parameter between early and absolute glaucoma, but notbetween early and advanced glaucoma.Conclusions: For follow-up of glaucoma progression, RNFL measurements using scanninglaser polarimetry are more useful in the early stage than in the advancedstage.

  15. Measurements of 7Be radioactivity concentrations in high altitude air

    International Nuclear Information System (INIS)

    Preliminary measurements of the 7Be radioactivity concentrations in high altitude air were made between April 1984 and March 1985 in order to check the possibility of use for the analysis of the measured gross beta concentrations. Airborne dusts were collected with a filter type air sampler attached to the F-4EJ aircraft. The measurement of the 7Be radioactivity in the filters was made by gamma-ray spectrometry with a Ge(Li) detector. The results ranging from 0.03 to 5 pCi/m3 are in approximate agreement with the calculated values using the equation derived by B. Peters. Comparing the results of 7Be with the gross beta activity concentrations, it is shown that observations of 7Be is helpful in the study of environmental radioactivity as a tracer for air circulation. (author)

  16. Measurement of radioactive iodine at the time of emergency

    International Nuclear Information System (INIS)

    This manual is published to prescribe on a rapid measuring method for radioactive iodine when it is released accidentally into the atmosphere from nuclear facilities, that is, to obtain the data necessary for taking measures and evaluation at the time of emergency. It is described on the assumption that samples of measuring objects have been collected in the field in principle. The iodine isotopes released accidentally into the atmosphere are not limited to one kind, but normally contain the mixture of a few kinds. The method also can not select radioactive iodine only among radioactive nuclides, so that all the radioactive nuclides are sensed as 131I, thus the quantity of 131I is estimated always in excess. The measuring instrument is a conventional ?-scintillation survey meter with a NaI(Tl) scintillator. The manual comprises 6 chapters including introduction, measurement criteria, dust in air, drinking water, milk, and vegetables. At the end of the manual, further explanations on ?-scintillation survey meter, measured results of various environmental samples, and measurement of 131I in thyroid gland are described for reference. (Wakatsuki, Y.)

  17. Measurement of the absolute cross section for multiphoton ionization of atomic hydrogen at 248 nm

    Energy Technology Data Exchange (ETDEWEB)

    Kyrala, G.A.; Nichols, T.D.

    1990-01-01

    We present measurements of the absolute rates for multiphoton ionization of the ground state from atomic hydrogen by a linearly polarized, subpicosecond KrF laser pulse at a wavelength of 248 nm. A laser crossed atomic beam technique is used. The irradiance was varied from 3{times}10{sup 12} w/cm{sup 2} to 2{times}10{sup 14} w/cm{sup 2} and three above threshold ionization peaks were observed. The measured rate for total electron production is less than predicted by the numerical and perturbation calculations, but significantly higher than calculated by the Reiss and Keldysh methods. 21 refs., 7 figs.

  18. Measurement methodology of natural radioactivity in the thermal establishments

    International Nuclear Information System (INIS)

    The thermal baths have been identified as an activity susceptible to expose to ionizing radiations the workers through the natural sources of radon and radon 220. The new regulation obliges these facilities to realize radioactivity measurements. The principal ways of exposure are radon and its daughters inhalation,, exposure to gamma radiation, ingestion of radioelements in thermal waters. I.R.S.N. proposes two methods of measurements of the natural radioactivity in application to the regulation relative to the protection of persons and workers. Some principles to reduce exposure to radon are reminded. (N.C.)

  19. Absolute Position of Targets Measured Through a Chamber Window Using Lidar Metrology Systems

    Science.gov (United States)

    Kubalak, David; Hadjimichael, Theodore; Ohl, Raymond; Slotwinski, Anthony; Telfer, Randal; Hayden, Joseph

    2012-01-01

    Lidar is a useful tool for taking metrology measurements without the need for physical contact with the parts under test. Lidar instruments are aimed at a target using azimuth and elevation stages, then focus a beam of coherent, frequency modulated laser energy onto the target, such as the surface of a mechanical structure. Energy from the reflected beam is mixed with an optical reference signal that travels in a fiber path internal to the instrument, and the range to the target is calculated based on the difference in the frequency of the returned and reference signals. In cases when the parts are in extreme environments, additional steps need to be taken to separate the operator and lidar from that environment. A model has been developed that accurately reduces the lidar data to an absolute position and accounts for the three media in the testbed air, fused silica, and vacuum but the approach can be adapted for any environment or material. The accuracy of laser metrology measurements depends upon knowing the parameters of the media through which the measurement beam travels. Under normal conditions, this means knowledge of the temperature, pressure, and humidity of the air in the measurement volume. In the past, chamber windows have been used to separate the measuring device from the extreme environment within the chamber and still permit optical measurement, but, so far, only relative changes have been diagnosed. The ability to make accurate measurements through a window presents a challenge as there are a number of factors to consider. In the case of the lidar, the window will increase the time-of-flight of the laser beam causing a ranging error, and refract the direction of the beam causing angular positioning errors. In addition, differences in pressure, temperature, and humidity on each side of the window will cause slight atmospheric index changes and induce deformation and a refractive index gradient within the window. Also, since the window is a dispersive media, the effect of both phase and group indices have to be considered. Taking all these factors into account, a method was developed to measure targets through multiple regions of different materials and produce results that are absolute measurements of target position in three-dimensional space, rather than simply relative position. The environment in which the lidar measurements are taken must be broken down into separate regions of interest and each region solved for separately. In this case, there were three regions of interest: air, fused silica, and vacuum. The angular position of the target inside the chamber is solved using only phase index and phase velocity, while the ranging effects due to travel from air to glass to vacuum/air are solved with group index and group velocity. When all parameters are solved simultaneously, an absolute knowledge of the position of each target within an environmental chamber can be derived. Novel features of this innovation include measuring absolute position of targets through multiple dispersive and non-dispersive media, deconstruction of lidar raw data from a commercial off-the-shelf unit into reworkable parameters, and use of group velocities to reduce range data. Measurement of structures within a vacuum chamber or other harsh environment, such as a furnace, may now be measured as easily as if they were in an ambient laboratory. This analysis permits transformation of the raw data into absolute spatial units (e.g., mm). This technique has also been extended to laser tracker, theodolite, and cathetometer measurements through refractive media.

  20. Device for radioactivity measurement of liquid samples

    International Nuclear Information System (INIS)

    The device for low activity gamma measurements comprises an automatic changer for sample transfer from a conveyor to a measuring chamber. The conveyor includes a horizontal table were are regularly distributed sample holders. A lift allows a vertical motion of a plate for the exposition in front of a detector

  1. Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence

    International Nuclear Information System (INIS)

    Photoionization spectra have been recorded in the 4s, 4p, and 3d resonance regions for the Kr I isoelectronic sequence using both the dual laser produced plasma (DLP) technique (at DCU) to produce photoabsorption spectra, and the merged ion beam and synchrotron radiation technique (at ASTRID) to measure absolute photoionization cross sections. Profile parameters are compared for the 4s-np resonances of Rb+ and Sr2+. Many 4p?ns, md transitions are identified with the aid of Hartree-Fock calculations, and consistent quantum defects are observed for the various ns and md Rydberg series. Absolute single and double photoionization cross sections recorded in the 3d region for Rb+ and Sr2+ ions show preferential decay via double photoionization. This is only the second report to our knowledge where both the DLP technique and the merged-beam technique have been used simultaneously to record photoionization spectra, and the advantages of both techniques (i.e., better resolution in the case of DLP and values for absolute photoionization cross sections in the case of the merged-beam technique) are highlighted

  2. A survey on calorimetric measurement for development of advanced radioactivity standards

    International Nuclear Information System (INIS)

    National Metrology Institute of Japan (NMIJ) at National Institute of Advanced Industrial Science and Technology (AIST) holds national standards of radioactivity, and secures the traceability for various radioactivity measurements based on Japan Calibration Service System. It is required to establish radioactivity standards with less uncertainty to ensure safe and efficient utilization of the radioactivity. Present status of the radioactivity standards of NMIJ is reported and the calorimetric measurement method as a candidate to sophisticate radioactivity standard is investigated. (J.P.N.)

  3. Radioactivity measurements of the HMI after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The report explains the methods applied and the data measured by the HMI campaign. The material is presented so as to be of interest also to readers who in general are not concerned with aspects of radiation protection. The data measured refer to the local dose rate and to radioactivity in the environment (air, rain, surface waters, soil, food, mother's milk. Also, results of measurements of samples from Eastern Europe are given. (orig./HP)

  4. Progress towards absolute intensity measurements of emissions from high temperature thermographic phosphors

    International Nuclear Information System (INIS)

    Phosphor thermometry has been successfully used in a number of applications ranging from turbo-machinery, pyrolysis, supersonic and hypersonic studies in the past few decades. There are a number of issues related to high temperature, which include faster decays, decreasing emission intensity and increasing blackbody radiation. Although absolute lifetime decay values are readily available, there has been no known work presenting absolute intensity measurements throughout the phosphors operating temperature range. This additional information could help design engineers facilitate phosphor and instrument selection, optimise system setup, and help estimate the performance of the technique at higher temperatures, for any given optical setup. A number of well known high temperature thermographic phosphors were investigated including YAG:Tm, YAG:Tb and Y2O3:Eu from 20 oC in an excess of 1000 oC. Both 355 and 266 nm excitation wavelengths from a Q-switched Nd:YAG laser were used. The subsequent emissions were passed through a narrowband interference filter to isolate the peak emission wavelengths, and were collected using PMT. The methodology for an absolute measurement, which requires a sound understanding of the PMT, including solid angle, collection efficiency, dynode gain, calibration and electronic temporal response for intensity measurements is presented and discussed. The results clearly indicate a variation in phosphor intensity with an increasing temperature, which is considerably different amongst different phosphors under different excitation wavelengths. The combined standard uncertainty of measurement was estimated to be approximately ±10.7%. The existing system was able to monitor intensity values up to 900 oC for Mg3F2GeO4:Mn phosphors, 1100 oC for Y2O3:Eu, 1150 oC for YAG:Tb and up to 1400 oC for YAG:Tm thermographic phosphors. Y2O3:Eu using 266 nm excitation was found to exhibit the highest peak intensity per mJ of laser excitation from all the phosphors investigated at 20 oC. However, at high temperatures (900 oC+) YAG:Tm using 355 nm excitation was found to exhibit the highest peak intensity per mJ of an excitation energy. - Research highlights: ? A number of high temperature thermographic phosphors were investigated. ? Absolute measurement technique is used. ? Variation in intensity with increasing temperature of different phosphors is shown. ? Detected emissive power varied proportionally with the detectors collection area. ? Detected emissive power varied inversely proportional to the distance squared.

  5. Krypton-85 and other airborne radioactivity measurements throughout Ireland

    International Nuclear Information System (INIS)

    In compliance with articles 35 and 36 of the EURATOM Treaty, the Radiological Protection Institute of Ireland (RPII) undertakes a comprehensive programme of radioactivity monitoring in the Irish terrestrial environment. Radioactivity is present in the terrestrial environment due to natural processes, the testing of nuclear weapons in the atmosphere, accidents such as the Chernobyl accident and the routine discharge of radionuclides from nuclear installations. The RPII monitors airborne radioactivity concentrations at ten stations throughout Ireland, of which, nine are equipped with low volume particulate samplers and one, in Dublin, with a high volume particulate sampler. The low volume particulate samples are assessed for total beta activity and high volume samples for gamma emitting radionuclides such as caesium-137 and beryllium-7. In addition, air sampled at the RPII laboratory in Dublin, is monitored for krypton-85, a radioactive noble gas, released into the environment primarily as a result of the reprocessing of nuclear fuel at installations such as Sellafield in the UK and La Hague in France. Since the inception of the krypton measurements in 1993 a trend of increasing atmospheric concentrations has been observed. The results of the krypton-85 monitoring, as well as the airborne radioactivity concentration measurements, will be presented and discussed in this paper. (author)

  6. Absolute Position Measurement in a Gas Time Projection Chamber via Transverse Diffusion of Drift Charge

    CERN Document Server

    Lewis, P M; Hedges, M T; Jaegle, I; Seong, I S; Thorpe, T N

    2014-01-01

    Time Projection Chambers (TPCs) with charge readout via micro pattern gaseous detectors can provide detailed measurements of charge density distributions. We here report on measurements of alpha particle tracks, using a TPC where the drift charge is amplified with Gas Electron Multipliers and detected with a pixel ASIC. We find that by measuring the 3-D topology of drift charge and fitting for its transverse diffusion, we obtain the absolute position of tracks in the drift direction. For example, we obtain a precision of 1~cm for 1~cm-long alpha track segments. To our knowledge this is the first demonstration of such a measurement in a gas TPC. This technique has several attractive features: it does not require knowledge of the initial specific ionization, is robust against bias from diffuse charge below detection threshold, and is also robust against high charge densities that saturate the detector response.

  7. Measurement of absolute flow rate in vessels using a stereoscopic DSA system

    International Nuclear Information System (INIS)

    We used a stereoscopic digital subtraction angiography (DSA) system to measure absolute blood flow rates in vessels. The magnification factor and the three-dimensional orientation of a selected vessel are obtained from automated analysis of stereoscopic DSA images. The cross-sectional area of the vessel is determined from the vessel diameter, which is measured with an iterative deconvolution technique. The time required for fluid to flow through a selected segment of a vessel is determined from the automated analysis of contrast medium 'time-density' curves. The effectiveness of these combined techniques was demonstrated in measurement of rates of both continuous and pulsatile flow in a vessel phantom, with the actual flow rate calibrated volumetrically or by an electromagnetic flowmeter. We have obtained accuracies in measured flow rates of approximately 5% and 18% for continuous and pulsatile flow respectively. (author)

  8. Absolute Density Calibration Cell for Laser Induced Fluorescence Erosion Rate Measurements

    Science.gov (United States)

    Domonkos, Matthew T.; Stevens, Richard E.

    2001-01-01

    Flight qualification of ion thrusters typically requires testing on the order of 10,000 hours. Extensive knowledge of wear mechanisms and rates is necessary to establish design confidence prior to long duration tests. Consequently, real-time erosion rate measurements offer the potential both to reduce development costs and to enhance knowledge of the dependency of component wear on operating conditions. Several previous studies have used laser-induced fluorescence (LIF) to measure real-time, in situ erosion rates of ion thruster accelerator grids. Those studies provided only relative measurements of the erosion rate. In the present investigation, a molybdenum tube was resistively heated such that the evaporation rate yielded densities within the tube on the order of those expected from accelerator grid erosion. This work examines the suitability of the density cell as an absolute calibration source for LIF measurements, and the intrinsic error was evaluated.

  9. Common mistakes associated with absolute full energy peak efficiency measurements using high pure germanium detectors

    International Nuclear Information System (INIS)

    The present work focuses on the uncertainties associated with absolute full energy peak efficiency (AFEPE) when measurements of calibration point sources conducted at various distances from two high pure germanium detectors (HPGe) from Ortec and Eurisys. A set consists of 11 point sources from Amersham were used. The measurements were performed at different source to detector distances. All the spectra were unfolded and analyzed using Emc plus MCA card from Silena. Full energy peak efficiency for each energy was then calculated using the well-know formula. The first approach was to fit the experimental data using least square fitting. Following that, a comparison between the experimental and calculated results was performed. The scattering data due to measurements of the multi-energetic sources specially when measurements carried out at very close distances from the detector were plotted and discussed.(author)

  10. Improved Measurement of Absolute Hadronic Branching Fractions of the Ds+ Meson

    CERN Document Server

    Onyisi, P U E; Cinabro, D; Smith, M J; Zhou, P; Naik, P; Rademacker, J; Edwards, K W; Briere, R A; Vogel, H; Rosner, J L; Alexander, J P; Cassel, D G; Das, S; Ehrlich, R; Gibbons, L; Gray, S W; Hartill, D L; Heltsley, B K; Kreinick, D L; Kuznetsov, V E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Sun, W M; Yelton, J; Rubin, P; Lowrey, N; Mehrabyan, S; Selen, M; Wiss, J; Libby, J; Kornicer, M; Mitchell, R E; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Hietala, J; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Xiao, T; Powell, A; Thomas, C; Wilkinson, G; Asner, D M; Tatishvili, G; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Napolitano, J; Ecklund, K M; Insler, J; Muramatsu, H; Pearson, L J; Thorndike, E H; Artuso, M; Blusk, S; Mountain, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M

    2013-01-01

    The branching fractions of Ds meson decays serve to normalize many measurements of processes involving charm quarks. Using 586 pb^-1 of e+ e- collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for 13 Ds decays in 16 reconstructed final states with a double tag technique. In particular we make a precise measurement of the branching fraction B(Ds -> K- K+ pi+) = (5.55 +- 0.14 +- 0.13)%, where the uncertainties are statistical and systematic respectively. We find a significantly reduced value of B(Ds -> pi+ pi0 eta') compared to the world average, and our results bring the inclusively and exclusively measured values of B(Ds -> eta' X)$ into agreement. We also search for CP-violating asymmetries in Ds decays and measure the cross-section of e+ e- -> Ds* Ds at Ecm = 4.17 GeV.

  11. Measurements of absolute hadronic branching fractions of $\\Lambda_{c}^{+}$ baryon

    CERN Document Server

    Ablikim, M; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Ferroli, R Baldini; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Dou, Z L; Du, S X; Duan, P F; Eren, E E; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Farinelli, R; Fava, L; Fedorov, O; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X L; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Goetzen, K; Gong, L; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Hao, X Q; Harris, F A; He, K L; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G S; Huang, J S; Huang, X T; Huang, Y; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kuehn, W; Kupsc, A; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C; Li, Cheng; Li, D M; Li, F; Li, F Y; Li, G; Li, H B; Li, J C; Li, Jin; Li, K; Li, Lei; Li, P R; Li, Q Y; Li, T; Li, W D; Li, W G; Li, X L; Li, X M; Li, X N; Li, X Q; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, Y B; Liu, Z A; Liu, Zhiqing; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Ma, Y M; Maas, F E; Maggiora, M; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Mitchell, R E; Mo, X H; Mo, Y J; Morales, C Morales; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, Y; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Qi, H R; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Santoro, V; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Ullrich, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, W P; Wang, X F; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, Z; Xia, L; Xia, L G; Xia, Y; Xiao, D; Xiao, H; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H J; Yang, H X; Yang, L; Yang, Y X; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zeng, Z; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y N; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, S H; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2015-01-01

    Using $567\\rm{pb}^{-1}$ of $e^+e^-$ collisions recorded at $\\sqrt{s}=4.599\\rm{GeV}$ with the BESIII detector, we report first measurements of absolute hadronic branching fractions of Cabibbo-favored decays of the $\\Lambda_{c}^{+}$ baryon with a double-tag technique. A global least-square fitter is utilized to improve the measured precision. Among the measurements for twelve $\\Lambda_{c}^{+}$ decay modes, the branching fraction for $\\Lambda_{c}^{+} \\rightarrow pK^-\\pi^+$ is determined to be $(5.84\\pm0.27\\pm0.23)\\%$, where the first uncertainty is statistical and the second is systematic. In addition, the measurements of the branching fractions of the other eleven Cabbibo-favored hadronic decay modes are significantly improved.

  12. Measuring the absorbed radioactivity during a flight

    International Nuclear Information System (INIS)

    This paper presents the new system SIEVERT developed by the General Direction of the Civil Aviation (DGAC) to measure the radiations doses absorbed from cosmic radiation. The system is available on the Internet site: www.sievert-system.org. (A.L.B.)

  13. Absolute efficiency measurements with the {sup 10}B based Jalousie detector

    Energy Technology Data Exchange (ETDEWEB)

    Modzel, G., E-mail: modzel@physi.uni-heidelberg [Physikalisches Institut, Universität Heidelberg, Neuenheimer Feld 226, 69120 Heidelberg (Germany); Henske, M. [CDT CASCADE Detector Technologies GmbH, Hans-Bunte-Str. 8–10, 69123 Heidelberg (Germany); Houben, A. [Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen (Germany); Klein, M. [Physikalisches Institut, Universität Heidelberg, Neuenheimer Feld 226, 69120 Heidelberg (Germany); CDT CASCADE Detector Technologies GmbH, Hans-Bunte-Str. 8–10, 69123 Heidelberg (Germany); Köhli, M.; Lennert, P. [Physikalisches Institut, Universität Heidelberg, Neuenheimer Feld 226, 69120 Heidelberg (Germany); Meven, M. [Heinz Maier-Leibnitz Zentrum (MLZ), 85747 Garching (Germany); Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS), Outstation at MLZ, 85747 Garching (Germany); Schmidt, C.J. [CDT CASCADE Detector Technologies GmbH, Hans-Bunte-Str. 8–10, 69123 Heidelberg (Germany); GSI Detector Laboratory, Planckstr. 1, 64291 Darmstadt (Germany); Schmidt, U. [Physikalisches Institut, Universität Heidelberg, Neuenheimer Feld 226, 69120 Heidelberg (Germany); Schweika, W. [Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS), 52425 Jülich (Germany); European Spallation Source ESS AB, SE-22100 Lund (Sweden)

    2014-04-11

    The {sup 10}B based Jalousie detector is a replacement for {sup 3}He counter tubes, which are nowadays less affordable for large area detectors due to the {sup 3}He crisis. In this paper we investigate and verify the performance of the new {sup 10}B based detector concept and its adoption for the POWTEX diffractometer, which is designed for the detection of thermal neutrons with predicted detection efficiencies of 75–50% for neutron energies of 10–100 meV, respectively. The predicted detection efficiency has been verified by absolute measurements using neutrons with a wavelength of 1.17 ? (59 meV)

  14. Measurement of the absolute values of cross-sections in neutron photoproduction (1962)

    International Nuclear Information System (INIS)

    The absolute values of photoneutrons production cross-sections for the case of intermediate and heavy nuclei (lanthanium, cerium, tantalum, gold, lead and bismuth) are determined with an error of 15 per cent. The results obtained agree with theories in which the giant resonance is explained by the collective motion of the protons against the neutrons. The effect of the nuclear deformation on the shape of the giant resonance is seen in the case of Ta181, it will be possible to determine the quadrupole momenta of deformed nuclei with a good accuracy when we shall increase the statistics of measurements. (author)

  15. Direct, Absolute, and In Situ Measurement of Fast Electron Transport via Cherenkov Emission

    International Nuclear Information System (INIS)

    We present direct measurements of the absolute energy distribution of relativistic electrons generated in intense, femtosecond laser interaction with a solid. Cherenkov emission radiated by these electrons in a novel prism target is spectrally dispersed to obtain yield and energy distribution of electrons simultaneously. A crucial advance is the observation of high density electron current as predicted by particle simulations and its transport as it happens inside the target. In addition, the strong sheath potential present at the rear side of the target is inferred from a comparison of the electron spectra derived from Cherenkov light observation with that from a magnet spectrometer.

  16. Precise measurement of the absolute fluorescence yield of the 337 nm band in atmospheric gases

    OpenAIRE

    AIRFLY Collaboration; Ave, M.; Bohacova, M.; Curry, E.; Di Carlo, P.; Di Giulio, C.; Luis, P. Facal San; Gonzales, D.; Hojvat, C.; Hörandel, J.; Hrabovsky', M; Iarlori, M.; B. Keilhauer; Klages, H.; Kleifges, M.

    2012-01-01

    A measurement of the absolute fluorescence yield of the 337 nm nitrogen band, relevant to ultra-high energy cosmic ray (UHECR) detectors, is reported. Two independent calibrations of the fluorescence emission induced by a 120 GeV proton beam were employed: Cherenkov light from the beam particle and calibrated light from a nitrogen laser. The fluorescence yield in air at a pressure of 1013 hPa and temperature of 293 K was found to be $Y_{337} = 5.61\\pm 0.06_{stat} \\pm 0.21_{s...

  17. Utilization of coincidence criteria in absolute length measurements by optical interferometry in vacuum and air

    Science.gov (United States)

    Schödel, R.

    2015-08-01

    Traceability of length measurements to the international system of units (SI) can be realized by using optical interferometry making use of well-known frequencies of monochromatic light sources mentioned in the Mise en Pratique for the realization of the metre. At some national metrology institutes, such as Physikalisch-Technische Bundesanstalt (PTB) in Germany, the absolute length of prismatic bodies (e.g. gauge blocks) is realized by so-called gauge-block interference comparators. At PTB, a number of such imaging phase-stepping interference comparators exist, including specialized vacuum interference comparators, each equipped with three highly stabilized laser light sources. The length of a material measure is expressed as a multiple of each wavelength. The large number of integer interference orders can be extracted by the method of exact fractions in which the coincidence of the lengths resulting from the different wavelengths is utilized as a criterion. The unambiguous extraction of the integer interference orders is an essential prerequisite for correct length measurements. This paper critically discusses coincidence criteria and their validity for three modes of absolute length measurements: 1) measurements under vacuum in which the wavelengths can be identified with the vacuum wavelengths, 2) measurements under air in which the air refractive index is obtained from environmental parameters using an empirical equation, and 3) measurements under air in which the air refractive index is obtained interferometrically by utilizing a vacuum cell placed along the measurement pathway. For case 3), which corresponds to PTB’s Kösters-Comparator for long gauge blocks, the unambiguous determination of integer interference orders related to the air refractive index could be improved by about a factor of ten when an ‘overall dispersion value,’ suggested in this paper, is used as coincidence criterion.

  18. IAEA-MEL's AQCS programme for marine radioactivity measurements

    International Nuclear Information System (INIS)

    The main objectives of the IAEA-MEL's Analytical Quality Control Services (AQCS) for marine radioactivity measurements are discussed and future plans for the organization of intercomparison exercises and the production of certified reference materials are presented. The new developments should also include implementation of quality assurance programmes in Member States' laboratories, training in quality management and accreditation programmes. (author)

  19. Measurement of residual radioactivity in the facility being decommissioned

    International Nuclear Information System (INIS)

    After decommissioned, the site of a nuclear facility is necessary not to be contaminated with any radioactivity for site radioactive-free release. Major nuclides deposited on components, building floors, sites etc. are found to be 60Co, 137Cs and etc. Because the latter nuclides usually accompany 60Co, the detection nuclide characterizing contamination can be determined to be 60Co. The termination survey for the site release must be carried out on the condition that the residual radioactivity is a very low level, and the site is a very large area. In addition there is possibility that the detection of 60Co is disturbed by the background level due to 40K and other natural radioactivities. Therefore, the basis of the measuring system consists of several NaI detectors and electronic circuits mounted on a vehicle in order to enhance the efficiencies of detection and of measuring operation. Further, the position of measuring points will be determined by an auto-positioning apparatus. Our development program of the measuring system is going on and will be outlined in the presentation. (author)

  20. Development of Nondestructive Measuring Technique of Environmental Radioactive Strontium

    Science.gov (United States)

    Saiba, Shuntaro; Okamiya, Tomohiro; Tanaka, Saki; Tanuma, Ryosuke; Yoshida, Tatsuru; Murata, Jiro

    The Fukushima first nuclear power plant accident was triggered by the Japanese big earthquake in 2011. The main radioactivity concerned after the accident are I-131 (half-life 8.0 days), Cs-134 (2.1 years) and 137 (30 years), Sr-89 (51 days) and 90 (29 years). We are aiming to establish a new detection technique which enables us to realize quantitative evaluation of the strontium radioactivity by means of nondestructive measurement without chemical separation processing, which is concerned to be included inside foods, environmental water and soil around us, in order to prevent us from undesired internal exposure to the radiation.

  1. Measurement of nuclear cross sections using radioactive beams

    International Nuclear Information System (INIS)

    One of the main applications of the production and use of nuclear radioactive beams is the measurement of nuclear cross sections. In this work is used a 6 He nuclear radioactive beam (? emitting with half life 806.7 ms) for the study of the reaction 6 + 209 Bi which could have several products. This investigation was realized in collaboration with the personnel of the Nuclear Structure laboratory at the University of Notre Dame (U.S.A.) and the National institute of Nuclear Research and CONACyT by Mexico. (Author)

  2. ROKO-Database of the environmental radioactivity measurements in Slovenia

    International Nuclear Information System (INIS)

    ROKO is the acronym of the Environmental Radioactivity in Slovenian language Radioaktivnost v OKOlju. Computer database ROKO contains data of all measurements of the radioactivity in the environment in Slovenia. Data about radioactivity in the environment have been collected in Slovenia more or less regularly since 1961 on. Most results are gathered in the form of paper reports. Slovenian Nuclear Safety Administration (SNSA) has initiated the project of transfer of all those data into the electronic form and making it available for easy research. The database is designed so, that it contains all records, relevant for any kind of analyses and for the transfer to the international data systems. By the end of the summer 2005 a major part of data from previous years have already been transferred into the database and the user interface software is under development. It will allow the users to examine individual data records, to plot time history graphs or geographical contour plots. (author)

  3. Radioactivity measurements for the thin layer activation technique

    International Nuclear Information System (INIS)

    Thin layer activation (TLA) is one of the promising techniques employing radiotracers at low levels of radioactivity for material performance studies such as wear and corrosion. The principle of TLA is the creation of an appropriate radionuclide in a given material to a well defined depth of a selected area. This activation is realised by exposure of the component to a charged particle beam using, e.g., a cyclotron facility. If the material is subjected to mechanical or chemical degradation, any loss of the activated material will result in a loss in radioactivity of the activated component. The sensitivity of TLA technique is high due to the capability of low level radioactivity measurement performed by ? spectrometry. The sensitivity of TLA is below 0.1 ?m thickness loss or 1 ng mass loss. In the present paper, some applications of TLA in ongoing research at the Institute for Health and Consumer Protection of the European Commission are presented

  4. Determining radioactive aerosol concentrations using a surface radioactive contamination measurement device

    International Nuclear Information System (INIS)

    For experiments with dispersed radioactive aerosols in a radon-aerosol chamber (RAC), it is desirable to know the activity of the radioactive aerosols applied in the RAC. A COLIBRI TTC survey metre with an SABG-151 probe (Canberra, USA) was purchased for this purpose. The probe is designed for surface contamination measurements, and it is intended to measure the activity of aerosols deposited on the filters during experiments in the RAC. Since the probe is calibrated in a different geometry, its response in the authors' experimental geometry was simulated by a Monte Carlo method. The authors present a Monte Carlo model using MCNPX and an experimental verification of this probe model. (authors)

  5. Measurement and analysis of radioactive substances; Mesure et analyse de substances radioactives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Here are gathered the abstracts presented to the 3. summer university of the year 2001 whose main themes were the destructive (5 conferences) and nondestructive (8 conferences) analyses applied to nuclear industry. The points of view of different organisms (as DSIN: Directorate for the Safety of Nuclear Installations, IPSN: Institute of Nuclear Protection and Safety, OPRI: Office of Protection against Ionizing Radiations, TUI: Institute for Transuranium Elements, COGEMA, EDF: Electric Utilities, ANDRA: French National Agency for Radioactive Waste Management, CRLC Val d'Aurelle, France) concerning the needs involved in nuclear facilities control, the methods of radionuclide speciation in use internationally, the measurements and analyses of radioactive substances are given too as well as some general concepts concerning 1)the laser-matter interaction 2)the ions production 3)the quality applied to the measurements and analyses 4)the standard in activity metrology. (O.M.)

  6. PREMOS Absolute Radiometer Calibration and Implications to on-orbit Measurements of the Total Solar Irradiance

    Science.gov (United States)

    Fehlmann, A.; Kopp, G.; Schmutz, W. K.; Winkler, R.; Finsterle, W.; Fox, N.

    2011-12-01

    On orbit measurements starting in the late 1970's, have revealed the 11 year cycle of the Total Solar Irradiance (TSI). However, the absolute results from individual experiments differ although all instrument teams claim to measure an absolute value. Especially the data from the TIM/SORCE experiment confused the community as it measures 0.3 % lower than the other instruments, e.g. VIRGO/SOHO by PMOD/WRC, which clearly exceeds the uncertainty stated for the absolute characterization of the experiments. The PREMOS package on the PICARD platform launched in June 2010 is the latest space experiment by PMOD/WRC measuring the TSI. We have put great effort in the calibration and characterization of this instrument in order to resolve the inter-instrument differences. We performed calibrations at the National Physical Laboratory (NPL) in London and the Laboratory for Atmospheric and Space Physics (LASP) in Boulder against national SI standards for radiant power using a laser beam with a diameter being smaller than the aperture of the instrument. These measurements together with the World Radiometric Reference (WRR) calibration in Davos allowed to compare the WRR and the SI radiant power scale. We found that the WRR lies 0.18 % above the SI radiant power scale which explains a part of the VIRGO-TIM difference. The Total solar irradiance Radiometer Facility (TRF) at the LASP allows to generate a beam that over fills the apertures of our instruments, giving the presently best available representation of solar irradiance in a laboratory. These irradiance calibrations revealed a stray light contribution between 0.09 and 0.3 % to the measurements which had been underestimated in the characterization of our instruments. Using the irradiance calibrations, we found that the WRR lies 0.32 % above the TRF scale which in turn explains the full VIRGO-TIM difference. The first light PREMOS measurements in space confirmed our findings. If we use the WRR calibration, PREMOS yields a TSI value of 1365.5 ± 1.2 W/m2 (k=1) which is in excellent agreement with VIRGO (1365.4 W/m2). Else, applying the TRF calibration to PREMOS, we obtain a TSI value of 1360.9 ± 0.4 W/m2 (k=1) which is in excellent agreement with TIM (1361.3 W/m2).

  7. An absolute 3D measurement method using a 2D pattern based on digital moire

    Science.gov (United States)

    Liao, Jiarui

    With a remarkable evolution in the development of digital cameras, non-contact 3D measurement using computer vision has been rapidly developing in the past few decades. Excellent and well-accepted techniques include digital moire and stereo vision. An obvious drawback of digital moire is that it is not applicable to the measurement of significant discontinuities, which is common in this area of research. And in the process of measurement, error propagation is inevitable, especially under the condition of missing points. The reason for this shortcoming lies in its relative coding scheme. For stereo vision, it is based on triangulation which leads to an absolute measurement. However, correspondence searching and resolution limitation of measurement of lacking features are two of the major unsolved problems of stereo vision systems. Inspired by these two well-developed techniques, an absolute measuring method based on structured light is developed in this research, requiring only a camera and a projector. The philosophy behind the coding scheme is a hybrid of relativity to the center and absoluteness, or independence on every single point. The mathematical model of the system is described and theorems that relate to the guidance of designing such a system are introduced. Two important factors determine the accuracy of the 3D measurement: correspondence matching and calibration of the camera and the projector' parameters. For the correspondence matching, an image processing method is developed. Image subtraction, edge detection, grid permutation and establishment of sub-coordinate-systems are included in the algorithm. Aiming at the discontinuity measurement, discontinuous borders are marked out first by using a Gabor filter first. Epipolar geometry is then utilized in the process of searching out each corresponding points accurately on the image plane. Sub-pixel accuracy for correspondence matching can be achieved in this way. The second factor that affects the accuracy of the measurement system is concerned with the calibration of the whole system. A convenient calibration method for structured light systems is developed in this research. This calibration method significantly simplifies the calibration procedures, and experimental results are presented for the verification of this calibration method. And experiments verify accuracy of the whole measurement system. And its advantages over digital moire and stereo vision are presented and verified by experiments. However, this calibration method for structured light system is applicable to the existing methods that are based on the least squares minimization effort. The assumptions made for the calibration system are not suitable to the nonlinear stereo vision system. Moreover, the 2D planar pattern used in existing calibration methods cannot provide 3D information in the 3D space. To move it among different views will inadvertently introduce additional mechanical errors. An iterative calibration method is developed in order to solve the existing problems in the state-of-the-art calibration methods for stereo vision systems. It is the first time that an iterative calibration method is developed to solve the calibration of a two-camera system's calibration with iterations in the 3D space. Derivations are described for this iterative calibration algorithm using feedback control theory. Furthermore, the calibration target is designed and manufactured under specifications defined by the task has been created for. Experiments show the developed iterative calibration method based on feedback control can achieve convergent parameters. With the calibrated parameters, 3D measurement of the calibration target verifies the correctness and accuracy of this iterative calibration method. Hence, the contributions of this work are significant. An absolute 3D measurement system based on a 2D pattern using digital moire has been developed. At the same time, a novel calibration method for such a system has also been proposed and verified in this work. For investigation of calibration method on

  8. Absolute calibration of in vivo measurement systems using magnetic resonance imaging and Monte Carlo computations

    International Nuclear Information System (INIS)

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. This method uses magnetic resonance imaging (MRI) to determine the anatomical makeup of an individual. A new MRI technique is also employed that is capable of resolving the fat and water content of the human tissue. This anatomical and biochemical information is used to model a mathematical phantom. Monte Carlo methods are then used to simulate the transport of radiation throughout the phantom. By modeling the detection equipment of the in vivo measurement system into the code, calibration factors are generated that are specific to the individual. Furthermore, this method eliminates the need for surrogate human structures in the calibration process. A demonstration of the proposed method is being performed using a fat/water matrix

  9. Shielding for measuring radioactive-rays

    International Nuclear Information System (INIS)

    In FBR type reactors, a neutron flux detector is accommodated in a detector guide tube, which is inserted to the vicinity of a primary coolant pipeline passing through a wall for measuring delayed neutrons coming from the primary coolant circuit pipeline extended from a reactor container to an intermediate heat exchanger. There are disposed lead shieldings at the periphery of the neutron flux detector, boron carbide shieldings at the periphery of the lead shieldings and the primary coolant circuit pipeline for shielding neutrons from other than the primary cooling circuit pipeline. Upon disposing these shieldings, positional deviations were caused by installation errors between each of guide tubes and with respect to pipelines depending on the position of a penetrating sleeve. However, the errors could not be absorbed since the lead shieldings had a block structure. This problem can be solved by forming a space between neutron moderators and lead shieldings for absorbing installation errors upon fixing the detector guide tube. (N.H.)

  10. Radioactivity measurements in Egyptian Phosphate Mines and Their Significance As a Source of Hazardous Radioactive Waste

    International Nuclear Information System (INIS)

    Phosphate mines that may contain radioactive traces in the composition of their ores represent source of hazardous radioactive waste in the environment. Radioactivity measurements have been conducted in nine underground phosphate mines in the Egyptian Eastern Desert in order to estimate the occupational radiation exposure of mine workers in those mining sites. Measurements were carried out of airborne radon and its short- lived decay products (progeny) and thoron progeny, as well as radiation from mines walls, ceilings and floors. Conventional, well established techniques, methods and instrumentation were used to make these measurements. Comparison of experimental data and theoretical predictions showed partial agreement between these two sets of data. This result is partly attributed to the complex layout of these mines, which causes undesirable ventilation conditions, such as recirculation airflow patterns, which could not be adequately identified or quantified. The radiation data obtained were used to estimate the maximum Annual Dose (MAD), and other important occupational radiation exposure variables. These calculations indicate that in eight out of the nine mines surveyed, the MAD exceeded (by a factor of up to 7) the maximum recommended level by ICRP 60. Numbers of suggestions are made in order to reduce the MAD in the affected mines. This study could help in the estimation of the environmental impact of these mine operations on the environment

  11. An alternative approach to wavelength modulation spectroscopy for absolute measurements of gas parameters in industrial processes

    Science.gov (United States)

    Johnstone, Walter; Duffin, Kevin; McGettrick, Andrew; Stewart, George

    2007-09-01

    Wavelength modulation spectroscopy (WMS) with tunable diode lasers (TDLs) is the preferred technique for gas composition measurement in a growing number of industrial process control applications. Those systems using optical fiber cables or networks to address single or multiple sensing points are of particular interest. However, the conventional approaches suffer from a number of calibration / scaling factor issues which, although addressable, lead to added cost and accumulated errors in the final determination of gas concentration. Such issues are particularly problematic in industrial applications where the pressure may be varying and unknown. The target signal in WMS is an amplitude modulation (AM) component generated by the interaction of frequency modulation (FM) on the laser output with a rotational / vibrational gas absorption line function. However, direct laser amplitude modulation is also present and distorts the recovered target signals again leading to errors. Here we report an alternative approach in which we exploit the phase difference between the laser AM and the FM to provide direct recovery of the absolute gas absorption line function from which both the gas concentration and the pressure may be obtained from the depth and line width respectively. The method is absolute with no need for calibration thus eliminating the difficulties with the conventional approach. In our presentation, we report the basic principles of the technique and its experimental validation through a number of methane gas concentration and pressure measurements.

  12. Absolute wavelength measurement and fine structure determination in /sup 7/Li II

    Energy Technology Data Exchange (ETDEWEB)

    Riis, E.; Berry, H.G.; Poulsen, O.; Lee, S.A.; Tang, S.Y.

    1985-01-01

    The energy levels of two-electron atoms continue to provide rigorous tests of relativistic quantum theory, and of correlation effects within a multi-particle system. These interactions are determined perturbatively, with several approximations, and theoretical results often differ. It is critical to provide precise measurements of absolute wavelengths connecting these atomic energy levels to obtain a resolution of the precision of the different parts of such complex calculations. In this work, we report a high precision optical measurements in the 1s2s /sup 3/S - 1s2p /sup 3/P multiplet of Li II using fast-beam laser spectroscopy. A collinear interaction using both parallel and antiparallel laser and ion beams allows both for precise elimination of large Doppler shifts, and for a strong kinematic narrowing of the observed resonances, as compared with thermal beam experiments. The wavelengths of the observed resonance fluorescence radiation are determined by comparing them with simultaneously recorded saturated absorption profiles of molecular iodine hyperfine components. In turn, the absolute wavelengths of the iodine lines are obtained from precisely calibrated Fabry-Perot etalon fringes in a separate experiment. The final precision of the Li II wavelengths is 5 parts in 10/sup 9/, which is at a level of precision of 80 ppM of the QED corrections in the transition. 3 refs., 1 figs., 1 tab.

  13. Application of the 4 pigammaMethod to the Absolute Standardization of Radioactive Sources of Positron Emitters

    International Nuclear Information System (INIS)

    We discuss the application of the method known as 4 pigammacountingto the standardization of positron emitters. Monte Carlo simulations are used to calculate the detection efficiency of positrons emitted by the nuclides 22Na and 18F. Two experimental setups are used, both based on a NaI(Tl) well detector. The results of the standardizations are in good agreement with those obtained by other methods. It is shown that the 4 pigammamethod can be successfully used for the absolute standardization of sources of positron emitters. (Author) 23 refs

  14. Microfabricated Collector-Generator Electrode Sensor for Measuring Absolute pH and Oxygen Concentrations.

    Science.gov (United States)

    Dengler, Adam K; Wightman, R Mark; McCarty, Gregory S

    2015-10-20

    Fast-scan cyclic voltammetry (FSCV) has attracted attention for studying in vivo neurotransmission due to its subsecond temporal resolution, selectivity, and sensitivity. Traditional FSCV measurements use background subtraction to isolate changes in the local electrochemical environment, providing detailed information on fluctuations in the concentration of electroactive species. This background subtraction removes information about constant or slowly changing concentrations. However, determination of background concentrations is still important for understanding functioning brain tissue. For example, neural activity is known to consume oxygen and produce carbon dioxide which affects local levels of oxygen and pH. Here, we present a microfabricated microelectrode array which uses FSCV to detect the absolute levels of oxygen and pH in vitro. The sensor is a collector-generator electrode array with carbon microelectrodes spaced 5 ?m apart. In this work, a periodic potential step is applied at the generator producing transient local changes in the electrochemical environment. The collector electrode continuously performs FSCV enabling these induced changes in concentration to be recorded with the sensitivity and selectivity of FSCV. A negative potential step applied at the generator produces a transient local pH shift at the collector. The generator-induced pH signal is detected using FSCV at the collector and correlated to absolute solution pH by postcalibration of the anodic peak position. In addition, in oxygenated solutions a negative potential step at the generator produces hydrogen peroxide by reducing oxygen. Hydrogen peroxide is detected with FSCV at the collector electrode, and the magnitude of the oxidative peak is proportional to absolute oxygen concentrations. Oxygen interference on the pH signal is minimal and can be accounted for with a postcalibration. PMID:26375039

  15. Remote measurements of radioactivity distribution with BROKK robotic system - 16147

    International Nuclear Information System (INIS)

    Robotic system for the remote measurement of radioactivity in the reactor areas was developed. The BROKK robotic system replaces hand-held radiation measuring tools. The system consists of a collimated gamma detector, a standard gamma detector, color CCD video camera and searchlights, all mounted on a robotic platform (BROKK). The signals from the detectors are coupled with the video signals and are transferred to an operator's console via a radio channel or a cable. Operator works at a safe position. The video image of the object with imposed exposure dose rate from the detectors generates an image on the monitor screen, and the images are recorded for subsequent analysis. Preliminary work has started for the decommissioning of a research reactor at the RRC 'Kurchatov Institute'. Results of the remote radioactivity measurements with new system during radiation inspection waste storage of this reactor are presented and discussed. (authors)

  16. Evaluation of uncertainty and detection limits in radioactivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, M. [Universidad del Pais Vasco/Euskal Herriko Unibertsitatea, Escuela Tecnica Superior de Ingenieria de Bilbao, Alda. Urquijo, s/n, 48013 Bilbao (Spain); Idoeta, R. [Universidad del Pais Vasco/Euskal Herriko Unibertsitatea, Escuela Tecnica Superior de Ingenieria de Bilbao, Alda. Urquijo, s/n, 48013 Bilbao (Spain)], E-mail: raquel.idoeta@ehu.es; Legarda, F. [Universidad del Pais Vasco/Euskal Herriko Unibertsitatea, Escuela Tecnica Superior de Ingenieria de Bilbao, Alda. Urquijo, s/n, 48013 Bilbao (Spain)

    2008-10-01

    The uncertainty associated with the assessment of the radioactive content of any sample depends on the net counting rate registered during the measuring process and on the different weighting factors needed to transform this counting rate into activity, activity per unit mass or activity concentration. This work analyses the standard uncertainties in these weighting factors as well as their contribution to the uncertainty in the activity reported for three typical determinations for environmental radioactivity measurements in the laboratory. It also studies the corresponding characteristic limits and their dependence on the standard uncertainty related to those weighting factors, offering an analysis of the effectiveness of the simplified characteristic limits as evaluated by various measuring software and laboratories.

  17. Absolute Gravity and Global Positioning System Measurements of Uplift in Quebec and Eastern Ontario, Canada

    Science.gov (United States)

    Henton, J. A.; Liard, J. O.; Craymer, M. R.; Gagnon, C. G.; Lapelle, E.

    2003-12-01

    The Nouveau Quebec-Labrador region was the site of one of the major ice domes of the Laurentide Ice Sheet and is currently experiencing postglacial rebound. Geodetic data provide a useful and accurate method of measuring the pattern and rates of contemporary uplift in this region. In order to monitor the temporal variations in gravitational potential resulting from regional glacial isostatic adjustment, a number of absolute gravity sites have been established in northern Quebec. These absolute-gravity field stations are co-located with sites of the Canadian Base Network (CBN). Initiated in 1994, the CBN is a network of pillar monuments with forced-centering plates for Global Positioning System (GPS) receiver antennae. Accurately positioned three-dimensionally with GPS, the CBN can serve as a monitoring network for deformation studies of the Canadian landmass. Issues such as mass redistribution or changes in density contrasts within the Earth may be better addressed by monitoring positional changes (i.e., primarily height changes) and integrating these observations with gravitational variations. The comparison of the temporal rate of change of gravity with the GPS height rate is thus highly desirable. Recent velocity estimates based on both the multiple-epoch GPS network surveys as well as the preliminary results from absolute-gravity trends indicate regional uplift. These preliminary results also exhibit general agreement among the uplift rates for GPS radial velocities, gravity trends, and predictions of vertical crustal motion from postglacial rebound models. Monitoring the temporal rate of change of gravity at key GPS sites is also an important step towards the maintenance of an integrated reference system. Co-located with the Canadian Geodetic Long Baseline Interferometry site at the Algonquin Radio Observatory (A.R.O.), the Canadian Active Control System's continuous GPS station at Algonquin Park, Ontario (ALGO) serves as an important reference site for many regional surveys, including this study. A.R.O. has thus been singled out as a key field station where a comparison of the temporal rate of change of gravity with the GPS radial position rate of change is highly desirable. Unfortunately to date, the uplift rate determined from the gravity trend at Algonquin Park appears much larger than the GPS-observed and model-predicted rates. With the gravity measurements taken at the stable base of the Algonquin Radio Observatory's 46m VLBI telescope, the cause of this apparently high uplift rate is unknown. Although the data will be further analyzed for possible instrumental offsets or biases, it is likely that the gravity trend is biased by variations in the local mass budget due to environmental or hydrological effects. To quantify these effects, we have begun more frequent ( ˜monthly) absolute gravity measurements. Additionally, pending further testing and evaluation, data from an autonomous, continuously-recording (but yet to be installed) gravimeter will be coupled with the absolute measurements to develop and test models of seasonal variations in the gravity field at A.R.O. due to groundwater effects.

  18. The magnetic recoil spectrometer for measurements of the absolute neutron spectrum at OMEGA and the NIF

    International Nuclear Information System (INIS)

    The neutron spectrum produced by deuterium-tritium (DT) inertial confinement fusion implosions contains a wealth of information about implosion performance including the DT yield, ion-temperature, and areal-density. The Magnetic Recoil Spectrometer (MRS) has been used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute neutron spectrum from 3 to 30 MeV at OMEGA and 3 to 36 MeV at the NIF. These measurements have been used to diagnose the performance of cryogenic target implosions to unprecedented accuracy. Interpretation of MRS data requires a detailed understanding of the MRS response and background. This paper describes ab initio characterization of the system involving Monte Carlo simulations of the MRS response in addition to the commission experiments for in situ calibration of the systems on OMEGA and the NIF.

  19. The magnetic recoil spectrometer for measurements of the absolute neutron spectrum at OMEGA and the NIF

    Energy Technology Data Exchange (ETDEWEB)

    Casey, D. T.; Frenje, J. A.; Gatu Johnson, M.; Seguin, F. H.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Glebov, V. Yu.; Katz, J.; Magoon, J.; Meyerhofer, D. D.; Sangster, T. C.; Shoup, M.; Ulreich, J. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Ashabranner, R. C.; Bionta, R. M.; Carpenter, A. C.; Felker, B.; Khater, H. Y.; LePape, S.; MacKinnon, A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

    2013-04-15

    The neutron spectrum produced by deuterium-tritium (DT) inertial confinement fusion implosions contains a wealth of information about implosion performance including the DT yield, ion-temperature, and areal-density. The Magnetic Recoil Spectrometer (MRS) has been used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute neutron spectrum from 3 to 30 MeV at OMEGA and 3 to 36 MeV at the NIF. These measurements have been used to diagnose the performance of cryogenic target implosions to unprecedented accuracy. Interpretation of MRS data requires a detailed understanding of the MRS response and background. This paper describes ab initio characterization of the system involving Monte Carlo simulations of the MRS response in addition to the commission experiments for in situ calibration of the systems on OMEGA and the NIF.

  20. Static Absolute Force Measurement for Preloaded Piezoelements Used for Active Lorentz Force Detuning System

    CERN Document Server

    Sekalski, S P; Sekalski, S P

    2004-01-01

    To reach high gradients in pulsed operation of superconducting (SC) cavities an active Lorentz force detuning compensation system is needed. For this system a piezoelement can be used as an actuator (other option is a magnetostrictive device). To guarantee the demanded lifetime of the active element, the proper preload force adjustment is necessary. To determine this parameter an absolute force sensor is needed which will be able to operate at cryogenic temperatures. Currently, there is no calibrated commercial available sensor, which will be able to measure the static force in such an environment. The authors propose to use a discovered phenomenon to estimate the preload force applied to the piezoelement. The principle of the proposed solution based on a shape of impedance curve, which changes with the value of applied force. Especially, the position of resonances are monitored. No need of specialized force sensor and measurement in-situ are additional advantages of proposed method.

  1. Measurement of absolute rates for multiphoton ionization of atomic hydrogen at 248 nm

    Energy Technology Data Exchange (ETDEWEB)

    Kyrala, G.A.; Nichols, T.D. (Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (US))

    1991-08-01

    We present measurements of absolute rates for multiphoton ionization of the ground state of atomic hydrogen by a linearly polarized, subpicosecond KrF laser at a wavelength of 248 nm. The irradiance was varied from 3{times}10{sup 12} to 2{times}10{sup 14} W/cm{sup 2}, and three above-threshold-ionization peaks were observed. The measured rate for total electron production was less than that predicted by Floquet theory (S.-I. Chu and J. Cooper, Phys. Rev. A 32, 2769 (1985)) and perturbation calculations (S. V. Khristenko and S. I. Vetchinkin, Opt. Specktrosk. 40, 417 (1976)), but significantly higher than calculated by the Reiss (Phys. Rev. A 22, 1786 (1980)) and Keldysh (Sov. Phys.---JETP 20, 1307 (1965)) methods using Volkov final states.

  2. Diagnostics principle of microwave cut-off probe for measuring absolute electron density

    International Nuclear Information System (INIS)

    A generalized diagnostics principle of microwave cut-off probe is presented with a full analytical solution. In previous studies on the microwave cut-off measurement of weakly ionized plasmas, the cut-off frequency ?c of a given electron density is assumed to be equal to the plasma frequency ?p and is predicted using electromagnetic simulation or electric circuit model analysis. However, for specific plasma conditions such as highly collisional plasma and a very narrow probe tip gap, it has been found that ?c and ?p are not equal. To resolve this problem, a generalized diagnostics principle is proposed by analytically solving the microwave cut-off condition Re[?r,eff(??=??c)]?=?0. In addition, characteristics of the microwave cut-off condition are theoretically tested for correct measurement of the absolute electron density

  3. Absolute alpha activity measurements of some plants growing in monazite bearing soils in Sri Lanka

    International Nuclear Information System (INIS)

    Deposits of monazite bearing soils occur along the Southwest, West and East Coasts of Sri Lanka. High levels of gamma activity in some plant species growing in the West Coast have been reported. The high levels were due to the presence of the daughter nuclides of 232Th, most of which are alpha emitters. Absolute alpha activity measurements of ash samples of some plants growing in monazite bearing soils were carried out using the alpha sensitive polymeric nuclear track detector CR-39. The values ranged from 60-1900 mBq/g and were in good agreement with the values obtained from conventional scintillation counting method. The activity concentration of 228Th in the ash samples was also calculated by measuring the activity concentration of emanated thoron trapped inside a glass bottle with the use of a CR-39 track detector. (author)

  4. GENERAL: A diode laser spectrometer at 634 nm and absolute frequency measurements using optical frequency comb

    Science.gov (United States)

    Yi, Lin; Yuan, Jie; Qi, Xiang-Hui; Chen, Wen-Lan; Zhou, Da-Wei; Zhou, Tong; Zhou, Xiao-Ji; Chen, Xu-Zong

    2009-04-01

    This paper reports that two identical external-cavity-diode-laser (ECDL) based spectrometers are constructed at 634 nm referencing on the hyperfine B-X transition R(80)8-4 of 127I2. The lasers are stabilized on the Doppler-free absorption signals using the third-harmonic detection technique. The instability of the stabilized laser is measured to be 2.8 × 10-12 (after 1000 s) by counting the beat note between the two lasers. The absolute optical frequency of the transition is, for the first time, determined to be 472851936189.5 kHz by using an optical frequency comb referenced on the microwave caesium atomic clock. The uncertainty of the measurement is less than 4.9 kHz.

  5. A diode laser spectrometer at 634 nm and absolute frequency measurements using optical frequency comb

    International Nuclear Information System (INIS)

    This paper reports that two identical external-cavity-diode-laser (ECDL) based spectrometers are constructed at 634 nm referencing on the hyperfine B–X transition R(80)8–4 of 127I2. The lasers are stabilized on the Doppler-free absorption signals using the third-harmonic detection technique. The instability of the stabilized laser is measured to be 2.8 × 10?12 (after 1000 s) by counting the beat note between the two lasers. The absolute optical frequency of the transition is, for the first time, determined to be 472851936189.5 kHz by using an optical frequency comb referenced on the microwave caesium atomic clock. The uncertainty of the measurement is less than 4.9 kHz. (general)

  6. Precise measurement of the absolute fluorescence yield of the 337 nm band in atmospheric gases

    CERN Document Server

    Ave, M; Curry, E; Di Carlo, P; Di Giulio, C; Luis, P Facal San; Gonzales, D; Hojvat, C; Hörandel, J; Hrabovsky, M; Iarlori, M; Keilhauer, B; Klages, H; Kleifges, M; Kuehn, F; Li, S; Monasor, M; Nozka, L; Palatka, M; Petrera, S; Privitera, P; Ridky, J; Rizi, V; D'Orfeuil, B Rouille; Salamida, F; Schovanek, P; Smida, R; Spinka, H; Ulrich, A; Verzi, V; Williams, C

    2012-01-01

    A measurement of the absolute fluorescence yield of the 337 nm nitrogen band, relevant to ultra-high energy cosmic ray (UHECR) detectors, is reported. Two independent calibrations of the fluorescence emission induced by a 120 GeV proton beam were employed: Cherenkov light from the beam particle and calibrated light from a nitrogen laser. The fluorescence yield in air at a pressure of 1013 hPa and temperature of 293 K was found to be $Y_{337} = 5.61\\pm 0.06_{stat} \\pm 0.21_{syst}$ photons/MeV. When compared to the fluorescence yield currently used by UHECR experiments, this measurement improves the uncertainty by a factor of three, and has a significant impact on the determination of the energy scale of the cosmic ray spectrum.

  7. Measurement of the absolute branching ratios for semileptonic K± decays with the KLOE detector

    International Nuclear Information System (INIS)

    Using a sample of over 600 million ? ? K+K- decays collected at the DA?NE e+e- collider, we have measured with the KLOE detector the absolute branching ratios for the charged kaon semileptonic decays, K± ? ?0e±?(?) and K± ? ?0?±?(?). The results, BR(Ke3) = 0.04965±0.00038stat±0.00037syst and BR(K?3) = 0.03233±0.00029stat±0.00026syst, are inclusive of radiation. Accounting for correlations, we derive the ratio ?(K?3)/?(Ke3) = 0.6511±0.0064. Using the semileptonic form factors measured in the same experiment, we obtain |Vus f+(0)| = 0.2141 ±0.0013$

  8. Testing of an absolute measuring flat jack according to the compensation method (AWID)

    International Nuclear Information System (INIS)

    A measurement principle for a flat jack is being introduced by means of which stress measurements may be carried out without requiring any material parameters of the flat jack for the measurements. No calibration measurements are needed for this absolute measuring flat jack. A temperature dependence does not exist. A leap in the electrical resistance of the flat jack, which is brought about by two metal sheets separating when being pumped up with hydraulic oil at reaching of external pressure, is evaluated. Besides theoretical considerations on the mode of operation of the flat jack, laboratory tests were performed in an autoclave as well as in a tube filled with salt grit under a uniaxial press. The error which arose during measurements in the oil pressure autoclave was due to the magnitude of the reading accuracy of the measuring devices, i.e., it was smaller than 0.3% at 150 bars. This is to be considered as the error which may be assigned to the flat jack. Finally an arrangement of six flat jacks is treated for determining stress tensors in the heated area of the Temperature Test Field (TV 6) in the Asse salt mine. 5 refs.; 15 figs

  9. Absolute-scale measurement of Compton backscattering in germanium at 105.3 KeV

    International Nuclear Information System (INIS)

    The differential cross section d2?/dEd? was measured at incident photon energy of 105.3 keV in germanium (Z = 32). The experimental method used in the present experiment was introduced by the present authors previously. In the measurements, one detector serves as target and detector of ejected electrons, and another detector as detector of Compton-scattered photons. 155Eu was used as the source of photons. It gives a complex multi-line spectrum. We found that fast (multiple) cascades influence little the data of the 105.3 keV crossover transition. The calculations of other non-single Compton detector-to-detector scattering processes were made. As an improvement to our previous calculations, we have taken into account the finite dimensions of the cylindrical active volume of the detectors. Accordingly, the calculation of the detector efficiency was also improved. The absolute scale of the experimental Compton-scattering cross section was determined by cross talk between the two detectors via characteristic K? and K? x-rays of germanium with accuracy better than few percents. The values of the experimental cross section d2?/dEd? have been compared with corresponding values calculated by the impulse approximation with Hartree-Fock (HF) and hydrogen-like wave functions. The impulse approximation with HF wave functions gives excellent agreement to the experimental cross section, while the impulse approximation with hydrogen like wave functions give fairly agreement. The accurate absolute-scale values of Compton-scattering cross section from the present measurement and those from our previous measurements clearly show that HF wave functions are much better than the hydrogen-like wave functions in the description of Compton scattering data. (author)

  10. Measurement of radioactivity levels and assessment of radioactivity hazards of soil samples in Karaman, Turkey

    International Nuclear Information System (INIS)

    In this study, the levels of the natural and artificial radioactivity in soil samples collected from surrounding of Karaman in Turkey were measured. Activity concentrations of the concerned radionuclides were determined by gamma-ray spectrometry using a high-purity germanium detector with a relative efficiency of 40 % at 1.332 MeV. The results obtained for the 238U series (226Ra, 214Pb and 214Bi), 232Th series (228Ac), 40K and fission product 137Cs are discussed. To evaluate the radiological hazard of radioactivity in samples, the radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose and the external (Hex) and internal hazard index (Hin) were calculated and presented in comparison with the data collected from different areas in the world and Turkey. (authors)

  11. Radioactive targets for neutron-induced cross section measurements

    International Nuclear Information System (INIS)

    Measurements using radioactive targets are important for the determination of key reaction path ways associated with the synthesis of the elements in nuclear astrophysics (sprocess), advanced fuel cycle initiative (transmutation of radioactive waste), and stockpile stewardship. High precision capture cross-section measurements are needed to interpret observations, predict elemental or isotopical ratios, and unobserved abundances. There are two new detector systems that are presently being commissioned at Los Alamos National Laboratory for very precise measurements of (n,?) and (n,f) cross-sections using small quantities of radioactive samples. DANCE (Detector for Advanced Neutron-Capture Experiments), a 4 ? gamma array made up of 160 BaF2 detectors, is designed to measure neutron capture cross-sections of unstable nuclei in the low-energy range (thermal to ?500 keV). The high granularity and high detection efficiency of DANCE, combined with the high TOF-neutron flux available at the Lujan Center provides a versatile tool for measuring many important cross section data using radioactive and isotopically enriched targets of about 1 milligram. Another powerful instrument is the Lead-slowing down spectrometer (LSDS), which will enable the measurement of neutron-induced fission cross-section of U-235m and other short-lived actinides in a energy range from 1-200 keV with sample sizes down to 10 nanograms. Due to the short half-life of the U-235m isomer (T1/2 = 26 minutes), the samples must be rapidly and repeatedly extracted from its 239Pu parent. Since 239Pu is itself highly fissile, the separation must not only be rapid, but must also be of very high purity (the Pu must be removed from the U with a decontamination factor >1012). Once extracted and purified, the 235mU isomer would be electrodeposited on solar cells as a fission detector and placed within the LSDS for direct (n,f) cross section measurements. The production of radioactive targets of a few milligrams will be described as well as the containment for safe handling of these targets at the Lujan Center at LANSCE. To avoid any contamination, the targets are electrochemically fixed onto thin Ti foils and two foils are placed back to back to contain the radioactive material within. This target sandwich is placed in a cylinder made of aluminum with thin translucent windows made of Kapton. Actinides targets, such as 234,235,236,238U, 237Np, and 239Pu are prepared by electrodeposition or molecular plating techniques. Target thicknesses of 1-2 mg/cm2 with sizes of 1 cm2 or more have been made. Other targets will be fabricated from separation of irradiated isotopically enriched targets, such as 155Eu from 154Sm,171Tm from 170Er, and 147Pm from 146Nd, which has been irradiated in the high flux reactor at ILL, Grenoble. A radioactive sample isotope separator (RSIS) is in the process of being commissioned for the preparation of other radioactive targets. A brief summary of these experiments and the radioactive target preparation technique will be given.

  12. Our experience of blood flow measurements using radioactive tracers

    International Nuclear Information System (INIS)

    A critical study of blood flow measuring methods is proposed. After a review of the various diffusible and non-diffusible radioactive tracers and the corresponding detector systems, the principles which allow to measure blood flow from the data so obtained, are studied. There is a different principle of flow measurement for each type of tracer. The theory of flow measurement using non-diffusible tracers (human serum albumin labelled with 131I or sup(99m)Tc, 113In-labelled siderophiline) and its application to cardiac flow measurement are described first. Then the theory of flow measurement using diffusible tracers (133Xe, 85Kr) and its application to measurement of blood flow through tissues (muscles and kidney particularly) are described. A personal experience of this various flow measurements is reported. The results obtained, the difficulties encountered and the improvments proposed are developed

  13. Quartz crystal microbalance measurements of absolute laser photodeposition rates: Application to 257-nm deposition from W(CO)6

    International Nuclear Information System (INIS)

    A quartz crystal microbalance has been used to measure absolute rates of laser-induced photochemical deposition processes in real time. A cw UV laser (257 nm) focused at normal incidence onto the microbalance crystal surface is used to induce deposition by photodecomposition of an organometallic vapor. An equation is derived to obtain the absolute mass of the deposit. The method is demonstrated for photodeposition from W(CO)6

  14. Measures reducing incorporation of radioactive substances in emergency events

    International Nuclear Information System (INIS)

    In emergency events involving emission of radioactive nuclides, a major contribution to the radiation exposure of the population stems from incorporation of the substances. Based to a major part on literature studies, but also on own investigations, the authors show ways and means to influence the metabolic processes in connection with the radioactive substances taken in by the population through inhalation, through the skin, and ingestion of food and drinking water. The authors present a survey showing results achieved by measures reducing resorption and accelerating excretion. For evaluation of the the efficiency of the measures studied, a cost-benefit analysis has been made. Every interference in order to modify the resorptive or excretionary processes in man involve the risk of inducing a metabolic derangement. This is why the possibly resulting radiation injury is to be compared to the risks involved with treatment. (orig./MG)

  15. Renewal of centralized radioactivity measurement system for radiation control

    International Nuclear Information System (INIS)

    The centralized radioactivity measurement system has been used to carry out intensively measurements of a large number and variety of samples that are necessary for the control of radioactivity in the facilities of the JAERI Tokai Establishment and its environment. The operation of the system started in 1981, and presently the system processes more than 20,000 samples a year. However, the computers of the system have aged so much that the manufacturer's support and stable operation are no longer sure. Therefore, we renewed and restructured the computer system in 2003. A client-server system was adopted in the new system. The information of samples can be registered through the intranet. The clients can also confirm the progress of processing of their samples and browse the analytical results from their own computers. The renewed system can provide some convenience functions to the clients. (author)

  16. Measurements of radioactive and xenobiotic substances in the biosphere in the Netherlands 1983

    International Nuclear Information System (INIS)

    In this annual report the results and conclusions are given of measurements of radioactive and xenobiotic substances in the biosphere of the Netherlands. The measurements are coordinated by the Coordinating Committee for the Monitoring of Radioactive and Xenobiotic Substances (CCRX)

  17. Measures of treatment and disposal of radioactive wastes

    International Nuclear Information System (INIS)

    The fundamental policy of the countermeasures to radioactive wastes in Japan is determined based on the results of deliberation of the Expert Committee on Radioactive Waste Countermeasures, the Atomic Energy Commission. As to the high level wastes from reprocessing process, the results of deliberation were summarized in the Committee report of December, 1980, ''Promotion of research and development related to the treatment and disposal of high level radioactive wastes''. As to the low level wastes generated by the operation of nuclear power plants, there is the Committee report of June, 1982, ''On low level radioactive wastes''. In June, 1982, the long term plan of atomic energy development and utilization was revised on the basis of these reports. In order to promote the storage of low level wastes outside plant sites, the meeting for its examination was organized by the Science and Technology Agency, and the report was presented in July, 1983. By the instruction of the Atomic Energy Commission, the Expert Committee started anew the examination on the land disposal of low level and extremely low level wastes and the measures against high level and TRU wastes in December, 1983. The progress of these deliberations is reported. (Kako, I.)

  18. Radiation protection measures for the handling of unsealed radioactive materials

    International Nuclear Information System (INIS)

    The radiation protective medical measures are described which are required after contamination by radioactive materials or their incorporation. In the case of skin contamination, penetration by diffusion is explained and the maximum permissible value with regard to the various types of radiation is given. A detailed description of the decontamination measures including the necessary equipment follows. Indications for the treatment of injuries are given. In addition, incorporation due to inhalation, ingestion with intake through the skin are described, direct and indirect incorporation detection are explained, and the therapeutical possibilities and measures are gone into. (ORU/LH)

  19. National network of environment radioactivity measurements. Press kit

    International Nuclear Information System (INIS)

    This document first presents the objectives, challenges, context, operation and actors of the French national network of environment radioactivity measurements. It discusses the reasons for these measurements, the way they are performed, who perform them and how they are transmitted to the national network. It describes the quality policy for these measurements, and how this network is at the service of authorities, experts and population. It outlines the originality of the French approach within the European Union, and how this network takes the population expectations and their evolution into account

  20. A measurement of the absolute neutron beam polarization produced by an optically pumped 3He neutron spin filter

    International Nuclear Information System (INIS)

    The capability of performing accurate absolute measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with an absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically pumped polarized 3He spin filter and a relative transmission measurement technique. 3He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method

  1. A measurement of the absolute neutron beam polarization produced by an optically pumped sup 3 He neutron spin filter

    CERN Document Server

    Rich, D R; Crawford, B E; Delheij, P P J; Espy, M A; Haseyama, T; Jones, G; Keith, C D; Knudson, J; Leuschner, M B; Masaike, A; Masuda, Y; Matsuda, Y; Penttilae, S I; Pomeroy, V R; Smith, D A; Snow, W M; Szymanski, J J; Stephenson, S L; Thompson, A K; Yuan, V

    2002-01-01

    The capability of performing accurate absolute measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with an absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically pumped polarized sup 3 He spin filter and a relative transmission measurement technique. sup 3 He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method.

  2. Surveillance and control of containment by means of radioactive measurements

    International Nuclear Information System (INIS)

    In this paper, the radioactive measurements participating in the surveillance and control of the reactor containment as well as the possible procedures or operating rules related to, especially the ultimate procedures which could be implemented in case of a beyond of design accident, are presented. However, an overall view of the plant radiation monitoring system installed on the French plants is first given. If necessary, difference between 900 MW and 1300 MW units are emphasized

  3. Radioactivity measurement in imported food and food related items

    International Nuclear Information System (INIS)

    The Philippine Nuclear Research Institute (PNRI), formerly Philippine Atomic Energy Commission (PAEC) undertook the radioactivity monitoring of imported food and food-related products after the Chernobyl Plant accident in April 1986. Food samples were analyzed for 137Cs and 134Cs by gamma spectral method of analysis. This report deals with the measurement process and gives the result of the activity covering the period June 1986 to December 1987. (Auth.). 9 tabs., 7 figs., 4 refs

  4. Radon Natural Radioactivity Measurements for Evaluation of Primary Pollutants

    OpenAIRE

    Fenjuan Wang; Zhenyi Zhang; Maria Pia Ancora; Xiaodong Deng; Hua Zhang

    2013-01-01

    Radon is naturally released from the soil into the surface layer of the atmosphere, and by monitoring the natural radioactivity data of radon and its shot-live decay products we can get valuable information about the dilution properties of the lower boundary layer. This paper explores the dispersion characteristics of the lower layer of the atmosphere in Lanzhou, China, and the close relationship with the patterns of primary pollutants' concentrations. Measurements were conducted from July 20...

  5. Absolute luminosity and proton-proton total cross section measurement for the ATLAS experiment at LHC

    International Nuclear Information System (INIS)

    The Large Hadron Collider (LHC) at CERN in Geneva will soon deliver collisions with an energy never reached in a particle accelerator. An energy in the center of mass of 10 and ultimately 14 TeV will allow to go beyond the borders of the physics known so far. ATLAS, the largest detector ever built, will hunt the Higgs boson and search for new physics beyond the Standard Model. Any physical process is described by a cross section that measures its probability to occur. The events resulting from a given process are registered by ATLAS. To determine their according cross section, one has to know the luminosity. For the ATLAS experiment, a relative measurement of the luminosity can be done using the response of several sub-detectors. However to calibrate these detectors, an absolute measurement has to be performed. The ALFA detector has been designed to measure the elastic scattering spectrum that will allow to determine the absolute luminosity and the proton-proton total cross section. This provides an accurate calibration tool at a percent level. These detectors, located 240 m away from the interaction point, are called roman pots, a mechanical system that allows to approach a scintillating fiber tracker a few millimeters to the beam center. The simulation of the measurement requires to use a charged particles transport program. This program has to be carefully chosen because the determination of the protons lost during their travel from the interaction point to the detector has a major impact on the acceptance computation. The systematical uncertainties affecting the luminosity and the total cross section measurements are also determined using the full simulation chain. The ALFA detector operates in a complex environment and consequently its design requires a great care. A large tests campaign has been performed on the front end electronics. The results and the corresponding data analysis have shown that all requirement where fulfilled. A test beam has been preformed at each major step in the detector development. During these periods, the detector has been investigated under all aspects. The tracks reconstruction algorithm, the methods to extract the detection efficiency or the cross talk level are just a part of all the parameters that have to be determined. All these tests have confirmed the technical choices made so far and allowed to launch the serial production of the eight detectors that will be install in 2011 for the luminosity measurement. (author)

  6. Measurement of the Absolute Proton and Helium Flux at the Top of the Atmosphere using IMAX

    DEFF Research Database (Denmark)

    Menn, W.; Hof, M.

    1996-01-01

    The balloon-borne experiment IMAX launched from Lynn Lake, Canada in 1992 has been used to measure the cosmic ray proton and helium spectra from 0.2 GV to approximately 100 GV. The IMAX apparatus was designed to search for antiprotons and light isotopes using a superconducting magnet spectrometer with ancillary scintillators, time-of-flight, and aerogel cherenkov detectors. High resolution drift chambers and MWPCs were used as the tracking devices. Using redundant detectors, an extensive examination of the instrument efficiency was carried out. We present the absolute spectra of protons and helium corrected to the top of the atmosphere. The IMAX experiment was supported by NASA: RTOP 353-87-02 (GSFC), grants NAGW-1919 (Caltech) and NAGW-1418 (NMSU), and in Germany by the DFG and the BMFT. ^1 present address Max-Planck-Institut für Extraterrestrische Physik

  7. Absolute Polarization Measurements at RHIC in the Coulomb Nuclear Interference Region

    CERN Document Server

    Eyser, K O; Bravar, A; Bunce, G; Dhawan, S; Gill, R; Haeberli, W; Huang, H; Jinnouchi, O; Makdisi, Y; Nakagawa, I; Nass, A; Okada, H; Stephenson, E; Svirida, D; Wise, T; Wood, J; Zelenski, A

    2007-01-01

    The Relativistic Heavy Ion Collider at Brookhaven National Laboratory provides polarized proton beams for the investigation of the nucleon spin structure. For polarimetry, carbon-proton and proton-proton scattering is used in the Coulomb nuclear interference region at small momentum transfer ($-t$). Fast polarization measurements of each beam are carried out with carbon fiber targets at several times during an accelerator store. A polarized hydrogen gas jet target is needed for absolute normalization over multiple stores, while the target polarization is constantly monitored in a Breit-Rabi polarimeter. In 2005, the jet polarimeter has been used with both RHIC beams. We present results from the jet polarimeter including a detailed analysis of background contributions to asymmetries and to the beam polarization.

  8. Measurement of the Absolute Branching Fraction of D0 to K- pi+

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; /Bari U.; Eigen, G.; Ofte, I.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; /LBL, Berkeley

    2007-04-25

    The authors measure the absolute branching fraction for D{sup 0} {yields} K{sup -} {pi}{sup +} using partial reconstruction of {bar B}{sup 0} {yields} D*{sup +}X{ell}{sup -}{bar {nu}}{sub {ell}} decays, in which only the charged lepton and the pion from the decay D*{sup +} {yields} D{sup 0}{pi}{sup +} are used. Based on a data sample of 230 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, they obtain {Beta}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = (4.007 {+-} 0.037 {+-} 0.070)%, where the first error is statistical and the second error is systematic.

  9. Self-absorption-calibrated vacuum ultraviolet absorption spectroscopy for absolute oxygen atomic density measurement

    Science.gov (United States)

    Yang, Xiaoli; Sasaki, Koichi; Nagatsu, Masaaki

    2015-10-01

    Using a compact microwave plasma light source, a self-absorption-calibrated vacuum ultraviolet absorption spectroscopy (VUVAS) method was developed based on resonance escape factor theory and numerical analysis of the emission profile using Specair. After theoretical calibration of the self-absorption effect for two adjacent oxygen lines at 130.22?nm and 130.49?nm emitted from the light source, absolute oxygen atomic densities were measured for different N2/O2 gas mixture ratios in surface-wave plasmas. The oxygen atomic densities obtained for the two light probes were fairly close, supporting good reliability of the proposed self-absorption-calibrated VUVAS method. It is expected from the present results that the proposed method will extend the range of application of the VUVAS method in industrial plasma processing.

  10. Measurement of the absolute differential cross section of proton-proton elastic scattering at small angles

    CERN Document Server

    Mchedlishvili, D; Dymov, S; Bagdasarian, Z; Barsov, S; Gebel, R; Gou, B; Hartmann, M; Kacharava, A; Keshelashvili, I; Khoukaz, A; Kulessa, P; Kulikov, A; Lehrach, A; Lomidze, N; Lorentz, B; Maier, R; Macharashvili, G; Merzliakov, S; Mikirtychyants, S; Nioradze, M; Ohm, H; Prasuhn, D; Rathmann, F; Serdyuk, V; Schroer, D; Shmakova, V; Stassen, R; Stein, H J; Stockhorst, H; Strakovsky, I I; Ströher, H; Tabidze, M; Täschner, A; Trusov, S; Tsirkov, D; Uzikov, Yu; Valdau, Yu; Wilkin, C; Workman, R L; Wüstner, P

    2015-01-01

    The differential cross section for proton-proton elastic scattering has been measured at a beam energy of 1.0 GeV and in 200 MeV steps from 1.6 to 2.8 GeV for centre-of-mass angles in the range from 12-16 degrees to 25-30 degrees, depending on the energy. Absolute normalisations of typically 3% were achieved by studying the energy losses of the circulating beam of the COSY storage ring as it passed repeatedly through the windowless hydrogen target of the ANKE magnetic spectrometer. It is shown that the data have a significant impact upon a partial wave analysis. After extrapolating the differential cross sections to the forward direction, the results are broadly compatible with the predictions of forward dispersion relations.

  11. A study on the absolute measurement of ?-ray absorbed dose in the skin depth

    International Nuclear Information System (INIS)

    The absolute measurement of ? ray absorbed dose in the skin depth located at the certain distance from the radiation source (90Sr + 90Y, 204TI, 147Pm) recommended by the International Standardization Organization is performed by using an extrapolation chamber in the range of several mGy/h. Since one of critical points in measuring of absorbed dose is to make the environment in chamber similar to tissue, a new approach to the measurement of absorbed dose is proposed. The attenuation difference is minimized by deciding a window thickness such as the attenuation effect in chamber window becomes similar to that in the skin depth. A-150 tissue equivalent plastic, whose structure and density is very similar to tissue, is used for back material. The back scattering effect of both media is measured using the proposed method to calibrate the difference in back scattering effect between back material and tissue. For the measurement of back scattering effect of each material, an ionization chamber, whose structure is very similar to the extrapolation chamber and back material is replaceable, is made. Based on the results, ? ray absorbed dose in the skin depth of 70 ?m was measured as follows : 0.759 ?Gy/s (±3.78% ) for 90Sr + 90Y, 0.173 ?Gy/s (±4.17%) for 204TI and 0.088 ?Gy/s (±7.70%) for 147Pm. In order to evaluate the reliability of the proposed method, the absorbed dose measured in this study is compared to that measured in PTB (Physikalisch Technische Bundesanstalt) for the same ? ray source. Although the proposed method gives slightly higher value, the difference is within 1%. In conclusion, the proposed method seems to make the measuring environment closer to tissue, even though the calibration factor yielded by the proposed method has a little effect on evaluation of absorbed dose

  12. New method for absolute measurement of neutron flux in reactors operated at high power levels

    International Nuclear Information System (INIS)

    The objective of this thesis is to develop and study two methods of neutron measurements in nuclear reactors - new methods for measuring fast neutron fluxes, and Li6 semiconductor neutron spectrometer. It contains four chapters: Chapter I, Introduction covers the explanation of the need for neutron measurements in the reactor, and critical consideration of the existing methods for fast neutron flux measurements as well as methods for measuring the fast neutron spectra. Chapter II describes theoretical basis of semiconductor counters operation and their most important properties. Chapter III includes the description of the method developed by the author, long-tube method, and the results obtained by applying this method with the special emphasis on absolute measurements of fast neutron flux. Advantages and limitations of this method are discussed at the end of this chapter. Chapter IV contains intercomparison of the existing semiconductor spectrometers and emphasis of their positive and negative properties. A critical analysis of the results obtained by Li6 spectrometer with flat geometry in included. A new type of Li6 semiconductor spectrometer is described. Its properties are experimentally determined and it was compared to the classical Li6 spectrometer. Most of the experiments were done in the Physics Laboratory and at RA and RB reactors in the 'Boris Kidric' Institute of Nuclear Sciences in Vinca, and some at reactor in McMaster University, Hamilton, Canada. Experiments concerned with registering particles scattering were done at the Lockheed research reactor during fall 1963 in Belgrade. Neutron fluxes and spectra were measured by semiconductor counters improved and adapted for neutronic measurements by the author

  13. Absolute measurement of the isotopic ratio of a water sample with very low deuterium content

    International Nuclear Information System (INIS)

    The presence of H3+ ions which are indistinguishable from HD+ ions presents the principal difficulty encountered in the measurement of isotopic ratios of water samples with very low deuterium contents using a mass spectrometer. Thus, when the sample contains no deuterium, the mass spectrometer does not indicate zero. By producing, in situ, from the sample to be measured, water vapor with an isotopic ratio very close to zero using a small distilling column, this difficulty is overcome. This column, its operating parameters, as well as the way in which the measurements are made are described. An arrangement is employed in which the isotopic ratios can be measured with a sensitivity better than 0.01 x 10-6. The method is applied to the determination of the isotopic ratios of three low deuterium content water samples. The results obtained permit one to assign to the sample with the lowest deuterium content an absolute value equal to 1.71 ± 0.03 ppm. This water sample is a primary standard from which is determined the isotopic ratio of a natural water sample which serves as the laboratory standard. (author)

  14. Absolute measurement of radiation losses of a tokamak in the region of ultrasoft X-radiation

    International Nuclear Information System (INIS)

    In this work experiments were performed to investigate the question to which extent spectroscopic measurements in the ultrasoft X-ray region (lambda=1-10nm) are a useful technique for diagnosing the relatively cool edge region (Tsub(e)approx.=100-200 eV) of fusion-oriented plasmas. Object of these measurements was the plasma centre of a small tokamak where the plasma parameters are comparable to those in the edge region mentioned above. The measurements were done with a Bragg-spectrometer using either TAP (2d=2.59 nm) or lead stearate (2d=10.04 nm) as analyzer crystal. This allowed to cover the whole spectrum between 0.5 and 9 nm with one instrument. Using a photon-counting detector the spectrometer/detector system was absolutely calibrated by measuring the transmission of its different components by means of monochromatic X-ray radiation. For the investigated tokamak plasma intense line spectra in the region 1.4 nm =4.4 nm have been observed, where the former was caused by the high ionization stages of oxygen (OVII and OVIII), whereas the latter could be explained by Ar- to Na-like ions of the metallic impurities Fe, Cr, and Ni. (orig./HT)

  15. Direct comparison of a Ca+ single-ion clock against a Sr lattice clock to verify the absolute frequency measurement.

    Science.gov (United States)

    Matsubara, Kensuke; Hachisu, Hidekazu; Li, Ying; Nagano, Shigeo; Locke, Clayton; Nogami, Asahiko; Kajita, Masatoshi; Hayasaka, Kazuhiro; Ido, Tetsuya; Hosokawa, Mizuhiko

    2012-09-24

    Optical frequency comparison of the (40)Ca(+) clock transition ?(Ca)((2)S(1/2-)(2D(5/2), 729 nm) against the (87)Sr optical lattice clock transition ?(Sr) ((1)S(0)-(3)P(0), 698 nm) has resulted in a frequency ratio ?(Ca) / ?(Sr) = 0.957 631 202 358 049 9(2 3). The rapid nature of optical comparison allowed the statistical uncertainty of frequency ratio ?(Ca) / ?(Sr) to reach 1 × 10(-15) in 1000s and yielded a value consistent with that calculated from separate absolute frequency measurements of ?(Ca) using the International Atomic Time (TAI) link. The total uncertainty of the frequency ratio using optical comparison (free from microwave link uncertainties) is smaller than that obtained using absolute frequency measurement, demonstrating the advantage of optical frequency evaluation. We note that the absolute frequency of (40)Ca(+) we measure deviates from other published values by more than three times our measurement uncertainty. PMID:23037353

  16. Instituting the CEA rapid transmission network for environmental radioactivity measurement

    International Nuclear Information System (INIS)

    The radiological impact of the Chernobyl accident has been followed at CEA sites using measuring stations installed for monitoring the local environments. This has shown a need for respecification and improved coordination of the measurements in order to provide coherent radiological coverage of the CEA sites and by extension a potential contribution to national surveillance. The structure of the new measurement chain is based on the three stages of the evolution of an accident: real-time measurement of airborne activity, deferred spectrometric measurements of air, water and ground deposition activity and monitoring of significant links in the food chain. Radiological protection recommendations allow derivation of the levels of radioactivity which the equipment and methods must be able to detect. A rapid information transmission system allows the measurements to be collected together for the purposes of analysis and interpretation to the benefit of CEA central and site managements and of the public authorities

  17. Environmental radioactivity measurements at BNL following the Chernobyl accident

    International Nuclear Information System (INIS)

    Measurements are reported of the concentrations at Berkeley in Gloucestershire of radioactivity in the air, rainwater, tap water, soil, herbage and fresh vegetables for the period 29 April 1986 to 15 May 1986, following the Chernobyl Power Station accident. Data for up to 18 gamma emitting isotopes are reported, together with some limited actinide-in-air measurements. Deposition velocities are calculated and an assessment is presented of the sensitivity of the techniques employed. Some data are also included on the gaseous composition of the cloud and the isotope dependent dose rate from deposition. (author)

  18. Hair radioactivity as a measure of exposure to radioisotopes

    Science.gov (United States)

    Strain, W. H.; Pories, W. J.; Fratianne, R. B.; Flynn, A.

    1972-01-01

    Since many radioisotopes accumulate in hair, this tropism was investigated by comparing the radioactivity of shaved with plucked hair collected from rats at various time intervals up to 24 hrs after intravenous injection of the ecologically important radioisotopes, iodine-131, manganese-54, strontium-85, and zinc-65. The plucked hair includes the hair follicles where biochemical transformations are taking place. The data indicate a slight surge of each radioisotpe into the hair immediately after injection, a variation of content of each radionuclide in the hair, and a greater accumulation of radioactivity in plucked than in shaved hair. These results have application not only to hair as a measure of exposure to radioisotopes, but also to tissue damage and repair at the hair follicle.

  19. National audit of radioactivity measurements in Nuclear Medicine Centres

    International Nuclear Information System (INIS)

    Routine activity measurements of radiopharmaceutical solutions in Nuclear Medicine Centres (NMC) are carried out with the help of radionuclide calibrators (RC). These solutions are either ingested or injected to the patient for diagnosis or therapy. However, for the realization of an optimized examination, the activity of these radiopharmaceuticals must be determined accurately before administering it to patients. The primary standards are maintained by Radiation Standards Section, Radiological Physics and Advisory Division. National audit programmes of Iodine -131 activity measurements with RCs are conducted biannually to establish traceability to national standards and to check the status of nuclear medicine practice followed at the NMC. The results of fifteenth audit of 131I activity measurements with RC are presented in this paper. Questionnaires were sent to two hundred and thirty three NMCs in-the country. One hundred and nine NMC's agreed for participation and accordingly, glass vials containing radioactive 131I solution of nominal activity of 100 MBq were procured from Board of Radiation and Isotope Technology, Mumbai. The radioactivity in each vial was determined with high pressure re-entrant gamma ionisation chamber (GIC), a secondary standard maintained by this laboratory. The sensitivity coefficient of GIC is traceable to the primary standard. The standardized radioactive solution of 131I in glass vial was sent to each participant. Measurements results were reported in the reporting form sent. This audit was conducted in four schedules in Jan 2013. One hundred and sixty six results were received from one hundred and nine participants as many participants took measurements on more than one isotope calibrator

  20. Radioactive Sources in Medicine: Impact of Additional Security Measures

    International Nuclear Information System (INIS)

    For many years, medical centers and hospitals have utilized appropriate security measures to prevent theft or unauthorized use of radioactive materials. Recent anxiety about orphan sources and terrorism has heightened concern about diversion of radioactive sources for purposes of constructing a radiological dispersion device. Some medical centers and hospitals may have responded by conducting threat assessments and incorporating additional measures into their security plans, but uniform recommendations or regulations have not been promulgated by regulatory agencies. The International Atomic Energy Agency drafted interim guidance for the purpose of assisting member states in deciding what security measures should be taken for various radioactive sources. The recommendations are aimed at regulators, but suppliers and users also may find the recommendations to be helpful. The purpose of this paper is to describe threat assessments and additional security actions that were taken by one large and one medium-sized medical center and the impact these measures had on operations. Both medical centers possess blood bank irradiators, low-dose-rate therapy sources, and Mo-99/Tc-99m generators that are common to many health care organizations. Other medical devices that were evaluated include high-dose-rate after loaders, intravascular brachytherapy sources, a Co-60 stereotactic surgery unit, and self-shielded irradiators used in biomedical research. This paper will discuss the impact additional security has had on practices that utilize these sources, cost of various security alternatives, and the importance of a security culture in assuring the integrity of security measures without negatively impacting beneficial use of these sources. (Author) 10 refs

  1. Absolute measurement of the effective nonlinearities of KTP and BBO crystals by optical parametric amplification.

    Science.gov (United States)

    Armstrong, D J; Alford, W J; Raymond, T D; Smith, A V

    1996-04-20

    Absolute magnitudes of the effective nonlinearity, deff, were measured for seven KTP and six BBO crystals. The d(eff), were derived from the parametric gain of an 800-nm signal wave in the sample crystals when they were pumped by the frequency-doubled, spatially filtered light from an injectionseeded, Q-switched Nd:YAG laser. The KTP crystals, all type II phase matched with propagation in the X-Z plane, had d(eff) values ranging from 1.97 to 3.50 pm/V. Measurements of gain as a function of phase velocity mismatch indicate that two of the KTP crystals clearly contain multiple ferroelectric domains. For five type I phase-matched BBO crystals, d(eff) ranged from 1.76 to 1.83 pm/V, and a single type II phase-matched BBO crystal had a d(eff) of 1.56 pm/V. The uncertainty in our measurements of d(eff) values is ±5% for KTP and ±10% for BBO. PMID:21085331

  2. Femtosecond frequency comb measurement of absolute frequencies and hyperfine coupling constants in cesium vapor

    Science.gov (United States)

    Stalnaker, Jason E.; Mbele, Vela; Gerginov, Vladislav; Fortier, Tara M.; Diddams, Scott A.; Hollberg, Leo; Tanner, Carol E.

    2010-04-01

    We report measurements of absolute transition frequencies and hyperfine coupling constants for the 8S1/2, 9S1/2, 7D3/2, and 7D5/2 states in Cs133 vapor. The stepwise excitation through either the 6P1/2 or 6P3/2 intermediate state is performed directly with broadband laser light from a stabilized femtosecond laser optical-frequency comb. The laser beam is split, counterpropagated, and focused into a room-temperature Cs vapor cell. The repetition rate of the frequency comb is scanned and we detect the fluorescence on the 7P1/2,3/2?6S1/2 branches of the decay of the excited states. The excitations to the different states are isolated by the introduction of narrow-bandwidth interference filters in the laser beam paths. Using a nonlinear least-squares method we find measurements of transition frequencies and hyperfine coupling constants that are in agreement with other recent measurements for the 8S state and provide improvement by 2 orders of magnitude over previously published results for the 9S and 7D states.

  3. Femtosecond frequency comb measurement of absolute frequencies and hyperfine coupling constants in cesium vapor

    CERN Document Server

    Stalnaker, Jason E; Gerginov, Vladislav; Fortier, Tara M; Diddams, Scott A; Hollberg, Leo; Tanner, Carol E

    2010-01-01

    We report measurements of absolute transition frequencies and hyperfine coupling constants for the 8S_{1/2}, 9S_{1/2}, 7D_{3/2}, and 7D_{5/2} states in ^{133}Cs vapor. The stepwise excitation through either the 6P_{1/2} or 6P_{3/2} intermediate state is performed directly with broadband laser light from a stabilized femtosecond laser optical-frequency comb. The laser beam is split, counter-propagated and focused into a room-temperature Cs vapor cell. The repetition rate of the frequency comb is scanned and we detect the fluorescence on the 7P_{1/2,3/2} -> 6S_{1/2} branches of the decay of the excited states. The excitations to the different states are isolated by the introduction of narrow-bandwidth interference filters in the laser beam paths. Using a nonlinear least-squares method we find measurements of transition frequencies and hyperfine coupling constants that are in agreement with other recent measurements for the 8S state and provide improvement by two orders of magnitude over previously published res...

  4. Measurements of absolute radical densities in atmospheric pressure plasmas with complex gas mixtures

    Science.gov (United States)

    O'Connell, Deborah

    2015-05-01

    Low temperature plasmas are emerging as an exciting development for therapeutics. Non-equilibrium plasmas, operated at ambient atmospheric pressure and temperature, are very efficient sources for highly reactive neutral particles, including reactive oxygen and nitrogen species (RONS), which are known to play a crucial role in biological systems and existing therapeutics. Transport of these plasma components to the target is complex. In order to understand the chemical kinetics and plasma-liquid-biological interaction mechanisms measurements of the relevant RONS are key. Under atmospheric pressure these are challenging, primarily due to the multi-phase and highly collisional environment, requiring extremely high temporal (picosecond to nanosecond) and spatial (microns) resolution. Absolute measurements of radical densities (including O and OH) using picosecond two-photon absorption laser induced fluorescence (ps-TALIF), UV and high-resolution synchrotron VUV absorption spectroscopy will be presented. Fluorescence lifetime measurements of the laser-excited radicals are possible with picosecond resolution and this provides us with information about collisional quenching partners and thus collision kinetics with the surrounding environment. The authors acknowledge support by the UK EPSRC EP/H003797 and EP/K018388.

  5. Evaluation of the uncertainty of environmental measurements of radioactivity

    International Nuclear Information System (INIS)

    Results obtained by measurement of radioactivity have traditionally been associated with an expression of their uncertainty, based on the so-called counting statistics. This is calculated together with the actual result on the assumption that the number of counts observed has a Poisson distribution with equal mean and variance. Most of the nuclear scientific community has, therefore, assumed that it already complied with the latest ISO 17025 requirements. Counting statistics, however, express only the variability observed among repeated measurements of the same sample under the same counting conditions, which is equivalent to the term repeatability used in quantitative analysis. Many other sources of uncertainty need to be taken into account before a statement of the uncertainty of the actual result can be made. As the first link in the traceability chain calibration is always an important uncertainty component in any kind of measurement. For radioactivity measurements in particular counting geometry assumes the greatest importance, because it is often not possible to measure a standard and a control sample under exactly the same conditions. In the case of large samples there are additional uncertainty components associated with sample heterogeneity and its influence on self-absorption and counting efficiency. An uncertainty budget is prepared for existing data for 137Cs in Danish soil, which is shown to account adequately for all sources of uncertainty. (author)

  6. Particle sizing of airborne radioactivity field measurements at Olympic Dam

    International Nuclear Information System (INIS)

    On July 1, 1991 the Australian Radiation Laboratory (ARL) commenced a two year project entitled - Particle sizing of airborne radioactivity, funded by a Mining and Quarrying Occupational Health and Safety Committee - grant (submission No. 9138). This study was set out to measure airborne radioactivity size distributions in an underground uranium mine, in order to provide better estimates of the health risks associated with inhalation of airborne radiation in the work place. These measurements included both active and passive measurement of radon gas, continuous and spot sample of radon daughter levels, as well as wire screen diffusion battery measurements of the radon daughter size distributions. The results of measurements at over 50 sites within the mine are reported, together with the calculated dose conversion factors derived from the older dosimetric models and from the new ICRP lung model using the computer code RADEP. The results showed that the ventilation is relatively uniform within the mine and the radon daughter concentrations are kept to less than 20% of the equilibrium concentration. The radon and radon daughter concentrations showed marked variability with both time and position within the mine. It is concluded that the present radiation protection methods and dose conversion factors used in Australia provide a good estimate of the radiation risk for the inhalation of radon progeny. 29 refs., 8 tabs., 9 figs

  7. Measurement of gastric blood flow with radioactive microspheres

    International Nuclear Information System (INIS)

    The validity of using radioactive microspheres (15 +-- 5-mu m diameter) to measure gastric blood flow and its partition between gastric wall layers was investigated in anesthetized dogs with a chambered segment of gastric corpus. Total flow measured by a venous effluent technique demonstrated close correlation with microsphere-measured flow (r = 0.98, slope = 0.95) in 12 dogs given histamine, gastrin, or isoproterenol. In 12 histamine-stimulated dogs, mucosal flow measured by aminopyrine clearance and by microspheres also showed good agreement (r = 0.96, slope = 0.83). No evidence was found to indicate that microspheres altered hemodynamic or gastric function. In all experiments less than 1 percent of the total gastric radioactivity passed through arteriovenous shunts. The mucosa always contained a statistically adequate number of spheres (greater than 400), but the submucosa and muscularis frequently did not. Microspheres of all sizes mixed adequately in large arteries, but a significant difference was found in the distribution of 16- and 16-?m spheres between mucosa and submucosa, presumably because of streaming of the larger spheres past mucosal arteries. It was concluded that, with the techniques developed in our laboratory, microspheres could be a highly useful tool for quantitating gastric regional blood flow under a variety of experimental conditions

  8. Long distance absolute laser ranging at the nanometer precision level: the two-mode interference measurement in the Iliade rangemeter

    OpenAIRE

    Phung, Ha,; Courde, Clément; Brillet, Alain; Alexandre, Christophe; Lintz, Michel

    2013-01-01

    Some measurement schemes have been proposed and realized for the absolute measurement of long distances with an accuracy better than 10 nm. Published measurement setups use one or even two laser frequency combs. But significant engineering will be required to space qualify such a system. Simple methods, less technology-demanding would be valuable in the perspective of embedded instrumentation. We have designed and implemented a two-mode interference measurement scheme that allows sub-nanomete...

  9. From direct to absolute mass measurements a study of the accuracy of ISOLTRAP

    CERN Document Server

    Kellerbauer, A G; Bollen, G; Herfurth, F; Kluge, H J; Kuckein, M; Sauvan, E; Scheidenberger, C; Schweikhard, L; 10.1140/epjd/e2002-00222-0

    2003-01-01

    For a detailed study of the accuracy of the Penning trap mass spectrometer ISOLTRAP all expected sources of uncertainty were investigated with respect to their contributions to the uncertainty of the final result. In the course of these investigations, cross-reference measurements with singly charged carbon clusters $^{12}$C$^{+}_{n}$ were carried out. The carbon cluster ions were produced by use of laser-induced desorption, fragmentation, and ionization of C$_{60}$ fullerenes and injected into and stored in the Penning trap system. The comparison of the cyclotron frequencies of different carbon clusters has provided detailed insight into the residual systematic uncertainty of \\acro{ISOLTRAP} and yielded a value of $8 \\cdot 10^{-9}$. This also represents the current limit of mass accuracy of the apparatus. Since the unified atomic mass unit is defined as 1/12 of the mass of the $^{12}$C atom, it will be possible to carry out absolute mass measurements with \\acro{ISOLTRAP} in the future.\\\\[1\\baselineskip] PACS...

  10. In-Flight Measurement of the Absolute Energy Scale of the Fermi Large Area Telescope

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, M.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Ajello, M.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Allafort, A.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M.; /Stockholm U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm; Baldini, L.; /INFN, Pisa; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /INFN, Padua /Padua U.; Bechtol, K.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bellazzini, R.; /INFN, Pisa; Berenji, B.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bloom, E.D.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bouvier, A.; /UC, Santa Cruz; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari Polytechnic /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Buehler, R.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Buson, S.; /INFN, Padua /Padua U. /CSIC, Catalunya /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /IASF, Milan /DAPNIA, Saclay /INFN, Perugia /Perugia U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Unlisted, US /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /ASDC, Frascati /Perugia U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Montpellier U. /ASDC, Frascati /Bari Polytechnic /INFN, Bari /Naval Research Lab, Wash., D.C. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Montpellier U. /Bari Polytechnic /INFN, Bari /Ecole Polytechnique /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Ecole Polytechnique /Hiroshima U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Bari Polytechnic /INFN, Bari /INFN, Bari /NASA, Goddard /INFN, Perugia /Perugia U.; /more authors..

    2012-09-20

    The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to survey the gamma-ray sky from 20 MeV to several hundreds of GeV. In this energy band there are no astronomical sources with sufficiently well known and sharp spectral features to allow an absolute calibration of the LAT energy scale. However, the geomagnetic cutoff in the cosmic ray electron-plus-positron (CRE) spectrum in low Earth orbit does provide such a spectral feature. The energy and spectral shape of this cutoff can be calculated with the aid of a numerical code tracing charged particles in the Earth's magnetic field. By comparing the cutoff value with that measured by the LAT in different geomagnetic positions, we have obtained several calibration points between {approx}6 and {approx}13 GeV with an estimated uncertainty of {approx}2%. An energy calibration with such high accuracy reduces the systematic uncertainty in LAT measurements of, for example, the spectral cutoff in the emission from gamma ray pulsars.

  11. Absolute-scale measurement of compton backscattering in germanium at 105.3 keV

    International Nuclear Information System (INIS)

    The differential cross section d2?/dE d? was measured at an incident photon energy of 105.3 keV in germanium on absolute scale. The measurements were made using two high purity Ge detectors that operated in a coincidence mode. One detector served as the target and detector of ejected electrons, and another as the detector of Compton-scattered photons. It was found that fast (multiple) cascades have little influence on the data of the 105.3 keV crossover transition. An improved determination of the detector efficiency was made. The calculated values of the cross-section d2?/dE d? using the impulse approximation (IA) with Hartree-Fock (HF) wave functions are in excellent agreement with the experimental cross-sections, while the IA with hydrogen like (HL) wave functions give fair agreement. A comparison of the calculated values of the cross-sections obtained with HF and HL wave functions for each subshell in germanium gives new values for effective charges, which improve agreement between the results of IA with HL and experimental values. (author)

  12. Measurement of the Absolute Branching Fractions for $D^-_s\\!\\rightarrow\\!\\ell^-\\bar{\

    Energy Technology Data Exchange (ETDEWEB)

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, David Nathan; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U.; /more authors..

    2010-10-27

    The absolute branching fractions for the decays D{sub s}{sup -} {yields} {ell}{sup -}{bar {nu}}{sub {ell}} ({ell} = e, {mu}, or {tau}) are measured using a data sample corresponding to an integrated luminosity of 521 fb{sup -1} collected at center of mass energies near 10.58 GeV with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. The number of D{sub s}{sup -} mesons is determined by reconstructing the recoiling system DKX{gamma} in events of the type e{sup +}e{sup -}DKXD*{sub s}{sup -}, where D*{sub s}{sup -} {yields} D{sub s}{sup -}{gamma} and X represents additional pions from fragmentation. The D{sub s}{sup -} {yields} {ell}{sup 0}{nu}{sub {ell}} events are detected by full or partial reconstruction of the recoiling system DKX{gamma}{ell}. The branching fraction measurements are combined to determine the D{sub s}{sup -} decay constant f{sub D{sub s}} = (258.6 {+-} 6.4 {+-} 7.5) MeV, where the first uncertainty is statistical and the second is systematic.

  13. Gps, Superconducting and Absolute Gravimeters Measurements To Evaluate Crustal Deformations In Membach, Belgium.

    Science.gov (United States)

    van Camp, M.; Warnant, R.; Francis, O.

    We report on the results of 6 years of data from the absolute (AG) and superconducting gravimeters (SG) located at the Membach Station, eastern Belgium. By using the AG FG5, we were able to estimate the instrumental drift of the SG. SG gravity signal, corrected for Earth tides, ocean loading and atmospheric effects, polar motion and drift tracks changes in gravity observed by the AG at the µGal level. We distinguish two effects: a seasonal-like terms due to the uncorrected atmospheric loading effects and to hydrology variations. The second effect, which is the most interesting result, is the detection of a very low geophysical trend in gravity of -0.9 µGal/year at the Membach station. The SG drift stability, the rainfall effects, and the origin of the possible low trend are discussed. In particular, we compare those gravimetric measurements with continuous GPS measurements made since 1997 at 3 km from the station. The possible deformations could be linked to active faults in the Ardenne and/or bordering the Roer Graben, or linked to the possible Eifel plume.

  14. Use of proportional gas scintillator in absolute measurements of alpha-gamma emitter activities

    International Nuclear Information System (INIS)

    The absolute activity of U-235 contained in a U3 O8 sample was measured utilizing a sum-coincidence circuit which selects only the alpha particles which are simultaneous with the 143 KeV and 186 KeV gamma radiations from the Th-231 (product nucleus). The alpha particles were detected by means of a new type of a gas scintillating chamber, in which the light emitted by excitation of the gas atoms, due to the passage of a charged incoming particle, has its intensity increased by the action of an applied electric field. The gamma radiations were detected by means of a NaI(Tl) 1'' x 11/2'' scintillation detector. The value obtained for the half-life of U-235 was compared with the data available from various observers which used different experimental techniques. It is shown tht the results, are in excellent agreement with the best international data available on the subject and that, therefore, the sum-coincidence technique constitutes an important method for such measurements. (Author)

  15. In-Flight Measurement of the Absolute Energy Scale of the Fermi Large Area Telescope

    International Nuclear Information System (INIS)

    The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to survey the gamma-ray sky from 20 MeV to several hundreds of GeV. In this energy band there are no astronomical sources with sufficiently well known and sharp spectral features to allow an absolute calibration of the LAT energy scale. However, the geomagnetic cutoff in the cosmic ray electron-plus-positron (CRE) spectrum in low Earth orbit does provide such a spectral feature. The energy and spectral shape of this cutoff can be calculated with the aid of a numerical code tracing charged particles in the Earth's magnetic field. By comparing the cutoff value with that measured by the LAT in different geomagnetic positions, we have obtained several calibration points between ?6 and ?13 GeV with an estimated uncertainty of ?2%. An energy calibration with such high accuracy reduces the systematic uncertainty in LAT measurements of, for example, the spectral cutoff in the emission from gamma ray pulsars.

  16. Measurements of radioactive and xenobiotic substances in the biosphere in The Netherlands 1985

    International Nuclear Information System (INIS)

    In this annual report the results and conclusions are given of radioactive and xenobiotic substances in the biosphere of the Netherlands. The measurements are coordinated by the Coordination Committee for the Monitoring of Radioactive and Xenobiotic substances. (Auth.)

  17. Measurements of radioactive and xenobiotic substances in the biosphere in The Netherlands 1984

    International Nuclear Information System (INIS)

    In this annual report the results and conclusions are given of radioactive and xenobiotic substances in the biosphere of the Netherlands. The measurements are coordinated by the Coordination Committee for the Monitoring of Radioactive and Xenobiotic substances. (Auth.)

  18. Absolute Absorption Cross Section Measurements of Schumann-Runge Continuum of O2 at 90 K and 295 K

    International Nuclear Information System (INIS)

    Full text: Laboratory measurements of the absorption cross section of the Schumann-Runge continuum of O2 at the temperatures 90 K and 295 K have been made in the wavelength region 130 nm - 175 nm. The absolute absorption cross sections at the same temperatures have been measured at several discrete wavelengths through the region. The absolute cross sections of the O2 continuum have been used to put relative cross sections on a firm absolute basis throughout the region 130 nm - 175 nm. These recalibrated cross sections are available as numerical compilations. In the course of these experiment, we discovered that when using the stainless steel absorption cell the O2 gas temperature was not 78 K but was 90 K, because of thermal conduction through the inner tube

  19. Direct measurements of neutron capture on radioactive isotopes

    OpenAIRE

    Couture, A.; Reifarth, R

    2009-01-01

    We simulated the response of a 4p calorimetric g-detector array to decays of radioactive isotopes on the s-process path. The GEANT 3.21 simulation package was used. The main table contains estimates on the maximum sample size and required neutron flux based on the latest available neutron capture cross section at 30 keV. The results are intended to be used to estimate the feasibility of neutron capture measurements with 4p arrays using the time of flight technique.

  20. Environmental radioactivity measurements Using a compton suppression spectrometer

    International Nuclear Information System (INIS)

    The natural and artificial radioactivities of some environmental samples such as soil and vegetables have been studied through gamma-ray spectroscopy with a new constructed compton suppression spectrometer (CSS). The spectrometer consists of a 10% p-type HPGe detector as a main detector, an annular NE-102 A plastic scintillator as a guard detector, and a fast-slow coincidence system employing standard electronic modules for anti-compton operation. This study shows that CSS is a powerful tool for measuring the low level activities of environmental samples

  1. The observatories for the radioactivity. results of measures

    International Nuclear Information System (INIS)

    This IPSN's report on the monitoring of the radioactivity in France provides many graphs and tables of measures results recorded during the year 2000. The graphs show the activity levels (Bq or Bq fraction, per mass or volume unit) of many radionuclides in selected indicators and for levels upper than the detection limits. The metrology and the selected samples are presented. These samples are different for the three types of observatories: atmospheric, coast and terrestrial observatories. A chronological account of the results from 1959 to 2000 is also provided for the Cesium 137 and the beryllium 7 in the aerosols. (A.L.B.)

  2. Radon natural radioactivity measurements for evaluation of primary pollutants.

    Science.gov (United States)

    Wang, Fenjuan; Zhang, Zhenyi; Ancora, Maria Pia; Deng, Xiaodong; Zhang, Hua

    2013-01-01

    Radon is naturally released from the soil into the surface layer of the atmosphere, and by monitoring the natural radioactivity data of radon and its shot-live decay products we can get valuable information about the dilution properties of the lower boundary layer. This paper explores the dispersion characteristics of the lower layer of the atmosphere in Lanzhou, China, and the close relationship with the patterns of primary pollutants' concentrations. Measurements were conducted from July 2007 to May 2008 at one station and a fifty-day campaign was carried out at two stations in Lanzhou. The interpretation of radon radioactivity measurement showed that the measured atmospheric stability index (ASI) data at two stations in Lanzhou had statistically significant correlation, and well described the lower atmospheric layer mixing property in the area. The temporal trend of PM10 data was consistent with the temporal trend of ASI, with almost twice as high values in December than it in August. The results show that the ASI allows to highlight the dilution factor playing an important role in determining primary pollution events, and the mixing properties of the lower boundary layer is the key factor determining PM10 concentration in urban areas. PMID:23935426

  3. Measurement of indoor radon and natural/fall out radioactivity

    International Nuclear Information System (INIS)

    Indoor radon and natural radioactivity measurement surveys were carried out in various parts of the Punjab, Khyber Pakhtoonkha, FATA, Azad Jammu and Kashmir and Gilgit Baltistan using CR-39 based radon detectors. The annual effective dose, mean effective dose and exhalation rate were calculated for the general public. Indoor radon activity concentrations in the surveyed houses ranged from 12 +- 5 to 169 +- 9 Bq m/sup -3/ with an overall average value of 57 +- 30 Bq m/sup -3/ which is more than the world average of 40 Bq m/sup -3/. The indoor radon levels were maximum in winter and minimum during summer season and were within the recommended limits. Besides indoor radon and natural radioactivity measurements, uranium contents were determined in samples of drinking water collected from natural springs of Hatian Bala using fission track technique. Except in a few cases, the measured uranium concentration was found within the safe limit of 30 gL/sup -1/. (Orig./A.B.)

  4. The measurement of the radioactive aerosol diameter by position sensitive semiconductor detectors, 1

    International Nuclear Information System (INIS)

    The measurement of the diameter of radioactive aerosol, in particular plutonium aerosol, is very important for the internal dose estimation. Determination of the diameter of radioactive aerosol is performed by using position sensitive semiconductor detector (PSD). The filter paper with the radioactive aerosols is contacted to the PSD which is connected to the data processor so that the diameter of the aerosol is calculated from the measured radioactivity. This investigation was performed in cooperation with Rikkyo University. (author)

  5. Absolute frequency measurements of {sup 85}RbnF{sub 7/2} Rydberg states using purely optical detection

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L A M; Majeed, H O; Sanguinetti, B; Varcoe, B T H [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Becker, Th, E-mail: L.A.M.Johnson07@leeds.ac.u [Max Planck Institute of Quantum Optics, Hans Kopfermann Strasse 1 85748 Garching (Germany)

    2010-06-15

    A three-step laser excitation scheme is used to make absolute frequency measurements of highly excited nF{sub 7/2} Rydberg states in {sup 85}Rb for principal quantum numbers n=33-100. This work demonstrates the first absolute frequency measurements of rubidium Rydberg levels using a purely optical detection scheme. The Rydberg states are excited in a heated Rb vapour cell and Doppler-free signals are detected via purely optical means. All of the frequency measurements are made using a wavemeter that is calibrated against a Global Positioning System (GPS)-disciplined self-referenced optical frequency comb. We find that the measured levels have a very high frequency stability, and are especially robust against electric fields. The apparatus has allowed measurements of the states to an accuracy of 8.0 MHz. The new measurements are analysed by extracting the modified Rydberg-Ritz series parameters.

  6. Study of a 4??-? coincidence system for absolute radionuclide activity measurement using plastic scintillators

    International Nuclear Information System (INIS)

    The present work was intended to study a coincidence system 4?(PS)?-? for absolute activity measurement using plastic scintillators in 4? geometry. Along with experiments on the coincidence system, simulations were also performed applying the Monte Carlo Method, by means of codes PENELOPE and ESQUEMA. These simulations were performed in order to calculate the extrapolation curve of the coincidence system 4?(PS)?-? and compare it to experimental data. A new geometry was proposed to the coincidence system adding up a second photomultiplier tube to the previous system for improving light collection from the plastic scintillator, as this system presented limitations in the minimum detected energy due to the presence of electronic noise and low gain. The results show that an improvement in the signal-to-noise ratio was obtained, as well as in the minimum detected energy. Moreover, there was an increase in the detection efficiency. With these modifications, it is now possible to calibrate radionuclides which emit low energy electrons or X-rays, increasing the number of radionuclides that can be standardized with this type of system.(author)

  7. Frequency comparisons and absolute frequency measurements of 171Yb+ single-ion optical frequency standards

    CERN Document Server

    Peik, E; Schnatz, H; Schneider, T; Tamm, C; Karshenboim, S G; Tamm, Chr.

    2005-01-01

    We describe experiments with an optical frequency standard based on a laser cooled $^{171}$Yb$^+$ ion confined in a radiofrequency Paul trap. The electric-quadrupole transition from the $^2S_{1/2}(F=0)$ ground state to the $^2D_{3/2}(F=2)$ state at the wavelength of 436 nm is used as the reference transition. In order to compare two $^{171}$Yb$^+$ standards, separate frequency servo systems are employed to stabilize two probe laser frequencies to the reference transition line centers of two independently stored ions. The experimental results indicate a relative instability (Allan standard deviation) of the optical frequency difference between the two systems of $\\sigma_y(1000 {\\rm s})=5\\cdot 10^{-16}$ only, so that shifts in the sub-hertz range can be resolved. Shifts of several hertz are observed if a stationary electric field gradient is superimposed on the radiofrequency trap field. The absolute optical transition frequency of Yb$^+$ at 688 THz was measured with a cesium atomic clock at two times separated...

  8. 6 Years of Absolute and Superconducting Gravimeter Measurements in Membach, Belgium

    Science.gov (United States)

    Van Camp, M.; Francis, O.

    2001-12-01

    We report on the results of 6 years of data from the absolute (AG) and superconducting gravimeters (SG) located at the Membach Station, eastern Belgium. By using the AG FG5, we were able to estimate the instrumental drift of the SG. SG gravity signal, corrected for Earth tides, ocean loading and atmospheric effects, polar motion and drift tracks changes in gravity observed by the AG at the ? Gal level. We distinguish two effects: a seasonal-like terms due to the uncorrected atmospheric loading effects and to hydrology variations. The second effect, which is the most interesting result, is the detection of a very low geophysical trend in gravity of -0.3 ? Gal/year at the Membach station. If this trend is confirmed, assuming that the observed gravity change is only due to a vertical motion of the station, we can interpret that the Membach station is going up by 1 mm/year. The SG drift stability, the rainfall effects, and the origin of the possible low trend are discussed. In particular, the present deformations can be linked to active faults in the Ardenne and/or bordering the Roer Graben, or linked to the possible Eifel plume. In order to confirm this uplift and to estimate its wavelength, we are performing semi-annual AG measurements since 1999 along an 8 stations profile across the Ardenne and the Roer Graben.

  9. Comparison of absolute spectral irradiance responsivity measurement techniques using wavelength-tunable lasers

    International Nuclear Information System (INIS)

    Independent methods for measuring the absolute spectral irradiance responsivity of detectors have been compared between the calibration facilities at two national metrology institutes, the Helsinki University of Technology (TKK), Finland, and the National Institute of Standards and Technology (NIST). The emphasis is on the comparison of two different techniques for generating a uniform irradiance at a reference plane using wavelength-tunable lasers. At TKK's Laser Scanning Facility (LSF) the irradiance is generated by raster scanning a single collimated laser beam, while at the NIST facility for Spectral Irradiance and Radiance Responsivity Calibrations with Uniform Sources (SIRCUS), lasers are introduced into integrating spheres to generate a uniform irradiance at a reference plane. The laser-based irradiance responsivity results are compared to a traditional lamp-monochromator-based irradiance responsivity calibration obtained at the NIST Spectral Comparator Facility (SCF). A narrowband filter radiometer with a24 nm bandwidth and an effective band-center wavelength of 801 nm was used as the artifact. The results of the comparison between the different facilities, reported for the first time in the near-infrared wavelength range, demonstrate agreement at the uncertainty level of less than 0.1%. This result has significant implications in radiation thermometry and in photometry as well as in radiometry

  10. Prediction of absolute concentrations of elements from SR XRF scan measurements of natural wet sediments

    International Nuclear Information System (INIS)

    We report a method to predict absolute concentrations of elements in natural wet sediments (cores) from their SR XRF scan measurements. This prediction is problematic because: (i) relationship between fluorescent intensity and element concentrations is strongly biased by variability of pore water content in thick samples; (ii) thickness and mass of fluorescent layers are likewise variable; and (iii) spectral responses are perturbed by interference of elements. It is suggested to overcome these difficulties using an adapted algorithm of fundamental parameters. The mathematical model based on this algorithm accounts for two events of photon/matter interaction. Element concentrations are estimated using reference samples and the internal standard procedure, both with correction of interference effects. The pore water content is inferred from its correlation with the Rayleigh (coherent)/Compton (incoherent) scatter intensity ratio. Sediment density is found from water content by a reliable sedimentological law. Normalization to Compton scattering accounts for the irradiated mass of wet sediment controlled by porosity and sampling-related core disturbance. The mathematical model also includes these scattering variations related to lithology, water content, and density of samples. The new method was applied to SR XRF scans of cores from Lake Baikal and Lake Teletskoye to predict concentrations of 20 elements (K-Ba, REE, Th, U). Tests against ICP-MS and conventional SR XRF (with traditional pretreatment of samples) show good agreement and stability of SR XRF scanning. Neglect of the disturbing effects may cause errors up to 30-150%

  11. Using relative and absolute measures for monitoring health inequalities: experiences from cross-national analyses on maternal and child health

    OpenAIRE

    Huisman Martijn; Kunst Anton E; Houweling Tanja AJ; Mackenbach Johan P

    2007-01-01

    Abstract Background As reducing socio-economic inequalities in health is an important public health objective, monitoring of these inequalities is an important public health task. The specific inequality measure used can influence the conclusions drawn, and there is no consensus on which measure is most meaningful. The key issue raising most debate is whether to use relative or absolute inequality measures. Our paper aims to inform this debate and develop recommendations for monitoring health...

  12. Absolute Configurations of Spiroiminodihydantoin and Allantoin Stereoisomers: Comparison of Computed and Measured Electronic Circular Dichroism Spectra

    OpenAIRE

    Ding, Shuang; Jia, Lei; Durandin, Alexander; Crean, Conor; Kolbanovskiy, Alexander; Shafirovich, Vladimir; Broyde, Suse; Nicholas E. Geacintov

    2009-01-01

    The assignment of absolute configurations is of critical importance for understanding the biochemical processing of DNA lesions. The diastereomeric spiroiminodihydantoin (Sp) lesions are oxidation products of guanine and 8-oxo-7,8-dihydroguanine (8-oxoG), and the absolute configurations of the two diastereomers, Sp1 and Sp2, have been evaluated by experimental and computational optical rotatory dispersion (ORD) methods. In order to support our previous assignments by the ORD method, we calcul...

  13. Use of parallel plate avalanche detectors for absolute photofission cross section measurement on 238U and 232Th

    International Nuclear Information System (INIS)

    This paper is a digest of a series of studies on parallel plate avalanche detectors, built with the purpose of measuring absolute photofission cross section on 238U and 232Th. Besides a few theoretical recallings, we describe the experimental configuration, and point out the various problems met during its elaboration, and their respective solutions

  14. Recent developments at Saclay for measuring absolute cross sections of reactions between heavy ions by in-beam gamma techniques

    International Nuclear Information System (INIS)

    The potentiality of the in-beam gamma techniques to measure absolute cross sections in the fusion-evaporation domain is discussed. These techniques have been used (with Ge(Li) detectors) for more than one decade, but in view of the considerable progress which has been achieved in the last years, it seems worth while to reconsider to day their merits and limitations

  15. Absolute light yield measurements on SrF$_{2}$ and BaF$_{2}$ doped with rare earth ions

    CERN Document Server

    Shendrik, Roman

    2013-01-01

    Results of absolute light output measurements on strontium and barium fluoride doped with PrF$_3$ and CeF$_3$ are presented and compared with scintillators having well-known light output (NaI-Tl, CsI-Tl, BGO). For pure SrF$_2$ crystal we obtain a value of about 28600 photons/MeV.

  16. Radioactivity measurements in ceramics industries: results and comments

    International Nuclear Information System (INIS)

    As part of the NORM evaluation programme launched by the Spanish Nuclear Safety Council, a radiological study of the ceramics industry was carried out by the Environmental Radioactivity Laboratory of the Universidad Politecnica de Valencia. The study covered three types of plant: zircon sand milling, ceramic frit production and ceramic tile production, all of which use zircon as a raw material. In accordance with European Directive 96/29/Euratom, these types of plant are of radiological interest because of the presence of 238U and to a lesser extent 232Th, together with their progeny. The first step in the study was to collect information on materials and processes used in the different types of factory, after which a radiological characterization of the materials, including dust from the indoor environment, was performed. Gamma spectrometry analysis was carried out using a Ge(HP) detector. The second step was to identify the areas in which radioactive materials and workers were present. Direct measurements were carried out in different factory areas, which were radiologically characterized using a portable radiation monitor and thermoluminescent dosimeters. Finally, the external and internal radiation doses received by workers were estimated, on the basis of the aforementioned measurements. (author)

  17. Considerations on measurements of radioactivity in biological samples

    International Nuclear Information System (INIS)

    Radioactivity in biological samples and particularly in foodstuffs can be measured with several procedures, depending on the type of sample and radiation. In case of a radioactive fallout like the one from Chernobyl 1986, contamination in biological samples varies with time, being high immediately after the accident and decreasing successively with time. During the first stage, accurate measurements of gamma-emission should be made with high-resolution instruments, like HPGe-detectors coupled to multichannel analyzers in order to be able to assess the fallout's composition and separate the different nuclides. Even portable GM-counters and NaI(Tl)-detectors can be used, but they provide very limited information and the resolution of NaI(Tl) is too poor to make them suitable for other than survey purposes. In this case, they can be used for monitoring the activity in a certain area, or scanning a large amount of samples. After some months, when the activity has decayed and only a few nuclides are still active, the most important parameter is not resolution any longer, but sensitivity, since the content of radionuclides has decreased. At this stage NaI(Tl)-detectors assume greater importance and their sensitivity can permit the detection of low activity levels in relatively short time. The laboratory procedures for sample handling and preparation is also very important: established routines concentrated upon reducing the risk of contamination and minimizing sources of error must be used

  18. Environmental radioactivity monitoring in Lower Saxonia in 1991 and 1992. Joint report of the Lower Saxonian environmental radioactivity measuring stations

    International Nuclear Information System (INIS)

    The updated joint report of the lower Saxonian measuring stations for environmental radioactivity is for the years 1991 and 1992 and serves the purpose of providing information to interested citizens regarding the results of measurements. Technical terms are explained in the annex. Monitoring for environmental radioactivity (including foodstuffs and drinking water) has been carried through in Germany since the beginning of the 60s, when environmental radioactivity increased globally because of nuclear testing at that time. Measurements are executed by institutions of the federal government and laender on behalt of the federal government. Furthermore, measurements are regularly carried through in the surroundings of nuclear installations. Results are collected and evaluated by the federal authorities and regularly published by the Federal minister for environment, nature protection and reactor safety in the government's annual reports on ''Environmental radioactivity and radiation exposure''. Experiences with transfrontier radioactive contamination in the wake of the Chernobyl reactor accident prompted the federal government to intensify and reorganize environmental radioactivity monitoring. For this, the precautionary radiation protection law (StrVG) of 1986 provides the legal basis. (orig./HP)

  19. Radionuclide absolute left ventricular volumes during upright exercise: Validation in normal subjects by simultaneous hemodynamic measurements

    International Nuclear Information System (INIS)

    A nongeometric radionuclide technique for the determination of absolute left ventricular volumes was validated during exercise in nine normal subjects. Simultaneous reference stroke volume and cardiac output measurements were obtained by the Fick method. The reference left ventricular volumes were calculated by combining the Fick stroke volume and the isotopic ejection fraction. Data were collected at rest in the supine and upright positions and during 600 upright exercise, at three levels of increasing severity. At rest, from supine to upright position, the reference end-diastolic volume decreased significantly from 182+-24 ml to 154+-21 ml (mean +-SD,P<0.005); during upright exercise of low intensity, end diastolic volume increased to 176+-24 ml (P<0.05); at maximal exercise, end-diastolic volume was not different from the resting value in upright position. The end-systolic volume gradually decreased at rest from 67+-11 ml in the supine position to 54+-8 ml in the upright position (P<0.05) and to 32+-7 ml at maximal exercise (P<0.005). Compared with these reference data, the scintigraphic measurements were significantly lower on average by 23% for stroke volume, 21% for cardiac output, 22% for end-diastolic volume, and 23% for end-systolic volume. The overall changes in stroke volume (P<0.05) and end-systolic volume (P<0.001) occurring at rest during exercise were correctly detected by the scintigraphic method but the smaller changes in end-diastolic volume (less than 15%) were not (P<0.15) because they were within the range of the precision of the technique. If subtle changes in left ventricular volume are to be quantitated, attempts should be made to reduce the random variability of the scintigraphic method. (orig.)

  20. Some triple-filament lead isotope ratio measurements and an absolute growth curve for single-stage leads

    Science.gov (United States)

    Stacey, J.S.; Delevaux, M.E.; Ulrych, T.J.

    1969-01-01

    Triple-filament analyses of three standard lead samples are used to calibrate a mass spectrometer in an absolute sense. The bias we measure is 0.0155 percent per mass unit, and the precision (for 95% confidence limits) is ??0.13% or less for all ratios relative to 204Pb. Although its precision is not quite so good as that of the lead-tetramethyl method in the analysis of large samples, the triple-filament method is less complex and is an attractive alternative for smaller sample sizes down to 500 ??g. Triple-filament data are presented for six possibly single-stage lead ores and one feldspar. These new data for ores are combined with corrected tetramethyl data for stratiform lead deposits to compute absolute parameters for a universal single-stage lead isotope growth curve. Absolute isotopic ratios for primeval lead have been determined by Oversby and because all the previous data for both meteorites and lead ores were similarly fractionated, the absolute value of 238U 204Pb = 9.09 ?? 0.06 for stratiform leads is little different from the value 8.99 ?? 0.05 originally computed by Ostic, Russell and Stanton. Absolute values for lead isotope ratios for all interlaboratory standard samples presently available from the literature are tabulated. ?? 1969.

  1. Considerations on marine gross radioactivity measurements between 1982-1990

    International Nuclear Information System (INIS)

    This paper includes working details concerning gross alpha and beta measurements of components of the marine environment compared with oceanic fish. There are also included processing, interpretations and discussions on the results with specifications of the observations on this type of radioactivity. The alpha level is below the lower detection limit (LDL) for all samples except the green alga Bryopsis plumosa. The beta level is below LDL for water (salt), beach sand, molluscs-shell. The averages for algae, 84 Bq kg-1 f.w. molluscs - soft part, 118 Bq kg-1 f.w. marine fish, 113 Bq kg-1 f.w. oceanic fish. Bryopsis plumosa is in exception, with values of 103 Bq kg-1 f.w. The measurements in 1986 have not registered spectacular values of the activity of the medium-and long live radionuclides in the Romanian area of the Black Sea. (author) 1 fig., 2 tabs., 26 refs

  2. Using relative and absolute measures for monitoring health inequalities: experiences from cross-national analyses on maternal and child health

    Directory of Open Access Journals (Sweden)

    Huisman Martijn

    2007-10-01

    Full Text Available Abstract Background As reducing socio-economic inequalities in health is an important public health objective, monitoring of these inequalities is an important public health task. The specific inequality measure used can influence the conclusions drawn, and there is no consensus on which measure is most meaningful. The key issue raising most debate is whether to use relative or absolute inequality measures. Our paper aims to inform this debate and develop recommendations for monitoring health inequalities on the basis of empirical analyses for a broad range of developing countries. Methods Wealth-group specific data on under-5 mortality, immunisation coverage, antenatal and delivery care for 43 countries were obtained from the Demographic and Health Surveys. These data were used to describe the association between the overall level of these outcomes on the one hand, and relative and absolute poor-rich inequalities in these outcomes on the other. Results We demonstrate that the values that the absolute and relative inequality measures can take are bound by mathematical ceilings. Yet, even where these ceilings do not play a role, the magnitude of inequality is correlated with the overall level of the outcome. The observed tendencies are, however, not necessities. There are countries with low mortality levels and low relative inequalities. Also absolute inequalities showed variation at most overall levels. Conclusion Our study shows that both absolute and relative inequality measures can be meaningful for monitoring inequalities, provided that the overall level of the outcome is taken into account. Suggestions are given on how to do this. In addition, our paper presents data that can be used for benchmarking of inequalities in the field of maternal and child health in low and middle-income countries.

  3. Quality assurance of radioactivity measurements for soil samples in the investigation of national environmental natural radioactivity level

    International Nuclear Information System (INIS)

    The author summarizes the work of quality assurance of radioactivity measurements for soil samples in the investigation of national environmental natural radioactivity level. Examination of analytical methods of soil sample and inspection survey of analytical results for 29 provinces, municipalities, autonomy regions and cities of Wuhan and Baotou were introduced. The results of examination and inspection survey were given, and some technique problems involved were also discussed

  4. Radioactivity

    International Nuclear Information System (INIS)

    Large amounts of radioactivity can be released in nuclear accidents and nuclear explosions. Important events since the atomic bombs of 1945 are listed more or less in chronological order, including the nuclear weapons tests after World War II and the accidents recorded in nuclear facilities. (DG)

  5. Design and construction of a cryogenic facility providing absolute measurements of radon 222 activity for developing a primary standard

    International Nuclear Information System (INIS)

    Radon 222 metrology is required to obtain higher accuracy in assessing human health risks from exposure to natural radiation. This paper describes the development of a cryogenic facility that allows absolute measurements of radon 222 in order to obtain a primary standard. The method selected is the condensation of a radon 222 sample on a geometrically defined cold surface with a constant, well known and adjustable temperature and facing an alpha particles detector. Counting of the alpha particles reaching the detector and the precisely known detection geometry provide an absolute measurement of the source activity. After describing the cryogenic facility, the measurement accuracy and precision are discussed and a comparison made with other measurement systems. The relative uncertainty is below 1 pc (1 ?). The facility can also be used to improve our knowledge of the nuclear properties of radon 222 and to produce secondary standards. (author)

  6. Analysis, Design and Testing of a Novel Quasi-Zero-Stiffness based Sensor System for Measurement of Absolute Vibration Motion

    CERN Document Server

    Wang, Yu

    2015-01-01

    This study presents the analysis and design of a novel quasi-zero-stiffness (QZS) based vibration sensor system for measuring absolute displacement of vibrating platforms/objects. The sensor system is constructed by using positive and negative-stiffness springs, which makes it possible to achieve an equivalent QZS and consequently to create a broadband vibration-free point for absolute displacement measurement in vibrating platforms. Theoretic analysis is conducted for the analysis and design of the influence of structure parameters on system measurement performance. A prototype is designed which can avoid the drawback of instability in existing QZS systems with negative stiffness, and the corresponding data-processing software is developed to fulfill time domain and frequency domain measurements simultaneously. Both simulation and experiment results verify the effectiveness of this novel sensor system.

  7. Method for activity measurement in large packages of radioactive waste

    International Nuclear Information System (INIS)

    When evaluating the amount of radioactivity in a package of radioactive waste from gamma measurements (dose rates, overall gamma counting or gamma spectrometry), it is usually assumed that activity and mass distributions are homogeneous, in order to calculate a transfer function. Due to the fact that neither the mass distribution, nor the activity distribution is generally homogeneous, this assumption results in an error, which is to be evaluated. This error may have a systematic part, leading to a systematic over or under-estimation of the overall activity of a family of waste packages, and a stochastic part. An easy way to evaluate a maximal value of the possible error consist in assuming a hot spot inside the waste package gathering the whole activity of the waste matters and located at extreme positions. However this assumption leads to huge and widely over-estimated values of the error, due to the fact that the single hot spot distribution is very unlikely, and secondly it does not enable the estimation of the systematic part of the error. The proposed method, OPROF-STAT, enables a much finer evaluation of the uncertainty, with an estimation of the systematic part. OPROF-STAT is based on a computed generation of virtual packages, representative of the family of real packages whose activity is to be evaluated. (N.C.)

  8. Absolute measurement of the neutron sensitivity of a ZP1320 geiger-Mueller counter using the associated-particle technique

    International Nuclear Information System (INIS)

    Because of their low neutron sensitivity Geiger-Mueller counters are often used in mixed-field dosimetry to determine the photon dose fraction. The associated-particle technique has been used to determine absolutely the neutron sensitivity of an energy-compensated ZP 1320 Geiger-Mueller counter at 3 MeV. The measurement is consistent with previous measurements using this type of counter. (author)

  9. Environmental radioactivity measurements in Kastamonu region of northern Turkey.

    Science.gov (United States)

    Kam, Erol; Bozkurt, Ahmet

    2007-04-01

    Located in the north-western part of Turkey, the province of Kastamonu has lately been receiving national attention because of its cultural and touristic attractions. This study assesses the environmental radioactivity levels of the region through measurements of indoor radon concentrations and indoor/outdoor gamma absorbed dose in air and radionuclide activities in surface soil and drinking water. The indoor (222)Rn activity concentration was found to be 98.4 Bq/m(3) equivalent to an annual effective dose of 2.48 mSv. The indoor and outdoor gamma absorbed doses were measured as 54.81 and 48.03 nGy/h, respectively, corresponding to a total gamma radiation level (of terrestrial and cosmic origin) of 0.33 mSv/y. The activity concentrations in the soil samples collected from the study area were determined as 32.93, 27.17, 431.43 Bq/kg for the natural radionuclides (238)U, (232)Th and (40)K, respectively, and 8.02 Bq/kg for the fission product (137)Cs. These natural radioactivity sources result in a terrestrial gamma level of 60 microSv/y. The water samples collected from the region carry an average of 0.0089 Bq/l of gross alpha and 0.271 Bq/l of gross beta activities which together cause an annual effective dose of 1.83 microSv. The measurement results obtained in this study indicate that the region has a background radiation level that is within the natural limits and shows no significant departure from the other parts of the country. PMID:17207627

  10. Application of a graded screen array for size measurements of radioactive aerosols in accelerator rooms

    Energy Technology Data Exchange (ETDEWEB)

    Osada, N.; Kanda, H. [Kyoto Univ. (Japan). Graduate School of Engineering; Oki, Y.; Yamasaki, K.; Shibata, S. [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.

    2011-07-01

    A rapid measurement method for aerosol particle size is required to clarify the formation mechanism of freshly-formed radioactive aerosols in accelerator rooms. A graded screen array (GSA) method only requires brief sampling. Therefore, the GSA method is suitable for the measurement of radioactive aerosols in the accelerator rooms. In this work, a conventional GSA was applied to measure the particle size distribution of an aerosol. An influence of the radioactive gas on the GSA measurement was found. The adsorption of radioactive gases resulted in a discrepancy between the results of the GSA method and those of the diffusion battery method. An improved GSA method was developed to measure the radioactive aerosol formed in the accelerator room. The adsorption was measured by the improved GSA, and the influence of the radioactive gas was eliminated. The result of the improved GSA showed fair agreement with that of the diffusion battery system. (orig.)

  11. Precise measurement of the absolute fluorescence yield of nitrogen in air. Consequences on the detection of ultra-high energy cosmic rays

    International Nuclear Information System (INIS)

    The study of the energy spectrum of ultra-high energy cosmic rays (E > 1020 eV) requires to determine the energy with much more precision than what is currently achieved. The shower of particles created in the atmosphere can be detected either by sampling particle on the ground, or by detecting the fluorescence induced by the excitation of nitrogen by shower electrons. At present, the measurement of the fluorescence is the simplest and the most reliable method, since it does not call upon hadronic physics laws at extreme energies, a field still inaccessible to accelerators. The precise knowledge of the conversion factor between deposited energy and the number of fluorescence photons produced (the yield) is thus essential. Up to now, it has been determined with an accuracy of 15 % only. This main goal of this work is to measure this yield to better than 5 per cent. To do this, 1 MeV electrons from a radioactive source excite nitrogen of the air. The accuracy has been reached thanks to the implementation of a new method for the absolute calibration of the photomultipliers detecting the photons, to better than 2 per cent. The fluorescence yield, measured and normalized to 0.85 MeV, 760 mmHg and 15 Celsius degrees, is (4.23 ± 0.20) photons per meter, or (20.46 ± 0.98) photons per deposited MeV. In addition, and for the first time, the absolute fluorescence spectrum of nitrogen excited by a source has been measured with an optical grating spectrometer. (author)

  12. Measurement of the absolute flux from Vega in the K band (2.2 ?m)

    International Nuclear Information System (INIS)

    A method is described for determining absolute stellar flux in the infrared, based on a direct comparison between a star and a furnace at a known temperature. Observations have been made of Vega in the K band (2.2 ?m) using the Tenerife flux collector. The absolute flux from this star at the Earth, reduced to the wavelength 2.20 ?m, is found to be 0.375 x 10-9 W m-2 ?m-1 with an uncertainty of 8 per cent. (author)

  13. Experimental and numerical study of the degradation of radioactive measurements in the filters of airborne radioactive surveillance systems

    International Nuclear Information System (INIS)

    The measurement of radioactivity in the filters of airborne radioactive surveillance systems is a major metrology difficulty due to the fact that the absorption of a radiation in the filter media and the mass of aerosols accumulated distort the nuclear counting response. This thesis focuses on the determination of correction factors for the radioactivity loss in the survey filters. In a first step, radioactive filters representing the atmospheric samples have been prepared using the nuclear test bench ICARE. The experimental study on reference filters provided a database to determine correction factors for various filtration conditions. The second part proposes a new numerical method developed to determine the correction factors. It consists of coupling GeoDict for particles filtration simulations and MCNPX simulations for a transport in matter. The good agreement obtained by comparing the numerical and experimental correction factors has permitted to validate the numerical model

  14. Cross-Section Measurements with the Radioactive Isotope Accelerator (RIA)

    Energy Technology Data Exchange (ETDEWEB)

    Stoyer, M A; Moody, K J; Wild, J F; Patin, J B; Shaughnessy, D A; Stoyer, N J; Harris, L J

    2002-11-19

    RIA will produce beams of exotic nuclei of unprecedented luminosity. Preliminary studies of the feasibility of measuring cross-sections of interest to the science based stockpile stewardship (SBSS) program will be presented, and several experimental techniques will be discussed. Cross-section modeling attempts for the A = 95 mass region will be shown. In addition, several radioactive isotopes could be collected for target production or medical isotope purposes while the main in-beam experiments are running. The inclusion of a broad range mass analyzer (BRAMA) capability at RIA will enable more effective utilization of the facility, enabling the performance of multiple experiments at the same time. This option will be briefly discussed.

  15. Measuring and evaluation of ambient radioactivity due to mining activities

    International Nuclear Information System (INIS)

    Systematic measuring, examination and evaluation of ambient radioactivity due to mining activities in the Laender Saxonia, Thuringia and Sachsen-Anhalt is placed under the responsibility of the Federal Government pursuant to paragraph 11, para. 8 German act on Preventive Radiation Protection (StrVG). The purpose of this Federal obligation is to examine the special radiological situation in these federal states which results from coal and ore mining activities, and in particular from uranium ore mining since the end of the second world war. The field and laboratory tests are exclusively performed by local firms specializing in the subject. The final evaluation of data is done by the BfS. The data are stored in the A.LAS.KA database (cadastre of long-standing pollution or contamination). (orig./DG)

  16. Measuring the absolute deuterium–tritium neutron yield using the magnetic recoil spectrometer at OMEGA and the NIF

    International Nuclear Information System (INIS)

    A magnetic recoil spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.

  17. Measuring the absolute deuterium-tritium neutron yield using the magnetic recoil spectrometer at OMEGA and the NIF

    Energy Technology Data Exchange (ETDEWEB)

    Casey, D. T.; Frenje, J. A.; Gatu Johnson, M.; Seguin, F. H.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139 (United States); Glebov, V. Yu.; Katz, J.; Knauer, J. P.; Meyerhofer, D. D.; Sangster, T. C. [Laboratory for Laser Energetics, UR, Rochester, New York 14623 (United States); Bionta, R. M.; Bleuel, D. L.; Doeppner, T.; Glenzer, S.; Hartouni, E.; Hatchett, S. P.; Le Pape, S.; Ma, T.; MacKinnon, A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

    2012-10-15

    A magnetic recoil spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.

  18. Age classification of water sediments. Measurement of isotope radioactivity

    International Nuclear Information System (INIS)

    The aim of this study was to find out whether measurement of radioactivity of environmental isotopes can serve to make statements on the age of individual samples of water sediment. As a precondition, the sediment must originate form suspended matter that deposited more or less uniformly at least over certain time intervals (time windows). Samples exhibiting chaotically changing sedimentation and erosion can still not be dated at the present stage. Conclusions from measurements on environmental isotopes: The individual samples are compared with reference samples of suspended matter of the O-38?m size fraction with respect to radioactivity concentration. Then they are classified roughly in four age groups: largely new sediments (sedimentation approximately since the last high water); sediments largely dating back to around 1986; sediments largely dating back to the Nineteen Sixties, and sediments older than 1955 (including the botton ground). In addition, the class of new sediments can again be subdivided into four more finely distinguished age classes by means of beryllium-7(7Be). The samples may also contain admixtures from all other age classes. Twentyeight out of the total of 52 single samples from the Rhine, Weser, and Erft were classified as new sediment and proved capable of subclassification. The other samples exhibited no uniform sedimentation. Older fractions were predominant in this age spectrum. These fractions were again classified roughly in three age classes. The 14 samples of the oldest class contain large fractions of uncontaminated botton ground. This and other similar procedures could be used for the following practical applications: The age classes can be taken into account in the valuation of chemical parameters and can thus facilitate water quality assessment, depending on the exact problem under study; sediments of apredefined age can be extracted from several individual samples taken from selected sites and analysed to clarify the initial issue of past hazardous incidents and emission and deposition situations; age calssification may also help improve sampling strategies and techniques. (orig.)

  19. Measurements of whole-body radioactivity in the UK population

    International Nuclear Information System (INIS)

    A national survey of whole-body radioactivity was undertaken. A mobile whole-body counter visited collaborating Medical Physics Departments and Hospitals in England and Wales. Data were also obtained from an installed whole-body counter at the West Cumberland Hospital, Whitehaven, and from a control site at Addenbrooke's Hospital, Cambridge. 1657 volunteer members of the public were measured, including 162 children. 36% of volunteers had been measured in a similar survey 2 years earlier, and showed between a two and five fold reduction in body radiocaesium. No radiocaesium was detected in 54% of people measured. Measurements showed a progressive fall over the course of the study, reaching a baseline of 0.3 Bq137Cs/gK. In 1989, the additional radiation dose incurred from radiocaesium varied from a maximum of 4.1 ?Sv in Cumbria to 1.5 ?Sv in the South East, compared with the average annual radiation dose of 2500 ?Sv due to all other causes. No other gamma-emitting radionuclides were found. Results are consistent with Chernobyl as the source of the radiocaesium detected. (author)

  20. Measurements and evaluation of absolute emission probabilities for soft photons of 153Gd, 155Eu and 169Yb

    International Nuclear Information System (INIS)

    Absolute emission probabilities of Kx- and ?-rays in the energy region 40-200 keV have been obtained for 153Gd and 155Eu using measurements of emission rates by Ge, Ge(Li) and Si(Li)-detectors and of activities by a 4??-? coincidence system. The main results of our measurements and evaluation of decay data of 153Gd and 155Eu were published in 1992 and 1994. Here new experimental data concerning soft photon radiation which were obtained with a new Si(Li) spectrometer calibrated on the basis of a generalized energy response functions are presented. For the 14.06 keV ?-ray in the decay of 153Gd a value of (0.029 ± 0.003) photons per 100 disintegrations has been measured. For 155Eu the absolute emission probabilities of Kx- and 26.5, 45.3, 58.0, 60.0 ?-rays have been measured using the Si(Li) (formerly only a Ge-detector was used). A re-evaluated value of the 153Gd half-life is reported. For 169Yb the evaluation of decay data has been carried out taking into account the results of the latest measurements of absolute emission probabilities of ?-rays with energies 63.12, 109.80, 130.52 and 197.96 keV. (author)

  1. A measurement of the absolute neutron beam polarization produced by an optically-pumped $^{3}He$ spin filter

    CERN Document Server

    Rich, D R; Crawford, B E; Delheij, P P J; Espy, M A; Haseyama, T; Jones, G; Keith, C D; Knudson, J N; Leuschner, M B; Masaike, A; Masuda, Y; Matsuda, Y; Penttilä, S; Pomeroy, V R; Smith, D A; Snow, W M; Stephenson, S L; Thompson, A K; Yuan, V

    2002-01-01

    The capability of performing accurate measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically-pumped polarized 3He spin filter and a relative transmission measurement technique. 3He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method.

  2. Present status and prospects of ultralow level radioactivity measurements (2). Underground laboratory and recent topics emerged from ultralow level radioactivity measurements

    International Nuclear Information System (INIS)

    The present status of ultralow level radioactivity measurements in underground laboratories in Japan and Europe, and some researches using ultralow level radioactivity measurement technologies are stated. The background radiation originating cosmic ray is not excluded on the ground, but it decreased in the underground laboratory. Anticoincidence of underground measurement, countermeasure of radon, shielding materials, background of Ge measurement in Ogoya and other underground laboratories in Japan are reported. There are many underground laboratories for ultralow level radioactivity measurements in Europe, and a group of Collaboration of European Low-level underground LAboRatories (CELLAR) was organized. Some examples of ultralow level background of gamma ray measurements such as 152Eu, atomic bomb induced nuclide, natural induced radioactive nuclide by environmental neutron, measurement of 22Na, 108mAg and 110mAg, new evaluation method using 108mAg, high resolution analysis of change of 7Be and 210Pb in air, and nuclide in meteorite are reported. The sensitivity increasing method of low level radioactivity measurement and radioactive contamination of reagents are described. (S.Y.)

  3. Measurements of neutron cross sections of radioactive waste nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Katoh, Toshio [Gifu College of Medical Technology, Seki, Gifu (Japan); Harada, Hideo; Nakamura, Shoji; Tanase, Masakazu; Hatsukawa, Yuichi

    1998-01-01

    Accurate nuclear reaction cross sections of radioactive fission products and transuranic elements are required for research on nuclear transmutation methods in nuclear waste management. Important fission products in the nuclear waste management are {sup 137}Cs, {sup 135}Cs, {sup 90}Sr, {sup 99}Tc and {sup 129}I because of their large fission yields and long half-lives. The present authors have measured the neutron capture cross sections and resonance integrals of {sup 137}Cs, {sup 90}Sr and {sup 99}Tc. The purpose of this study is to measure the neutron capture cross sections and resonance integrals of nuclides, {sup 129}I and {sup 135}Cs accurately. Preliminary experiments were performed by using Rikkyo University Reactor and JRR-3 reactor at Japan Atomic Energy Research Institute (JAERI). Then, it was decided to measure the cross section and resonance integral of {sup 135}Cs by using the JRR-3 Reactor because this measurement required a high flux reactor. On the other hand, those of {sup 129}I were measured at the Rikkyo Reactor because the product nuclides, {sup 130}I and {sup 130m}I, have short half-lives and this reactor is suitable for the study of short lived nuclide. In this report, the measurements of the cross section and resonance integral of {sup 135}Cs are described. To obtain reliable values of the cross section and resonance integral of {sup 135}Cs(n, {gamma}){sup 136}Cs reaction, a quadrupole mass spectrometer was used for the mass analysis of nuclide in the sample. A progress report on the cross section of {sup 134}Cs, a neighbour of {sup 135}Cs, is included in this report. A report on {sup 129}I will be presented in the Report on the Joint-Use of Rikkyo University Reactor. (author)

  4. Radioactivity measurement in Austria 1992 and 1993. Data and evaluation

    International Nuclear Information System (INIS)

    The Federal Ministry of Health and Consumer Protection is responsible for the large scale surveillance of radioactive contaminations of the Austrian territory. For this purpose on one hand an on-line measurement system has been set up, using gamma dose rate measuring devices situated in 336 locations. On the other hand, various media e.g. aerosols, precipitation, surface water and foodstuffs are being collected. Their radionuclide content is analysed in several laboratories. Additional special projects have been set up to improve the knowledge of the time dependence respectively of regional aspects of the contamination situation. The report covers the results of this surveillance for the years 1992 and 1993. The evaluation of these measurements and of other data concerning the average exposure of the Austrian population for the year 1993 is summarized in the following figure. It can be seen that the main contributions to the radiation dose are due to natural exposure pathways, among which the inhalation of indoor radon is of main importance. (Compared to the data in earlier reports due to a new evaluation of the radon risk by ICRP this dose contribution is significantly lower.) In comparison, the component due to the consequences of the Chernobyl reactor accident in 1986 onto Austrian territory during 1992 and 1993 was marginal. (author)

  5. Radioactive effluent measurements at the Army Pulse Radiation Facility

    International Nuclear Information System (INIS)

    Staff from the Pacific Northwest Laboratory (PNL) performed measurements of the radioactive effluents emitted by the Army Pulse Radiation Facility (APRF). These measurements were performed by collecting the cooling air that passed by the APRF reactor as it operated, passing the air through filters to collect the particulates and iodines, and collecting samples of the air to be analyzed for noble gases. The reactor operated for four test runs, including two pulses and two steady state runs. After each reactor run, the filters were counted using gamma spectrometry to identify the nuclides and to determine the activity of nuclides deposited on the filters. The study provided radionuclide release fraction data that can be used to estimate the airborne emissions resulting from APRF operations. The release fraction for particulate fission products and radioiodines, as derived from these measurements, was found to be 8.9 x 10-6 for reactor pulses and 4.3 x 10-6 for steady state operation. These values compare to a theoretical value of 1.5 x 10-5

  6. The research of a method of absolute measurement for laser-driven high pressure equation of state

    CERN Document Server

    Huang Xiu Guang; Gu Yuan; Wu Jian; He Ju Hua; Luo Ping Qing; Ma Min Xun

    2002-01-01

    Numerical simulations of the whole physical process of aluminum flyer-vacuum-target directly driven by high power laser were presented. Simulation results showed that a symmetric impact will be realized between the flyer and the target and there is a wide stable area of shock wave propagation in the target if the parameters of flyer-vacuum-target and the conditions of laser match. And the absolute measurement of equation of state (EOS) may be approached if the structure parameters of flyer both-side-step-target are chosen reasonably. At the same time, the experimental researches of absolute measurement for EOS were conducted, and the experimental results are in accord with the simulation results on the whole

  7. Resolution limit of the white-light interferometric sensor for absolute position measurement based on central fringe maximum identification

    International Nuclear Information System (INIS)

    In this paper a simple theoretical analysis together with an experimental verification of the analysis that provides an estimation of the resolution limit of the white-light interferometric sensor for absolute position measurement based on central fringe maximum identification is presented. The resolution better than 10 pm is obtained in the white-light interferometric sensing system where the signal-to-noise ratio was greater than 80 dB. (paper)

  8. Absolutely calibrated, time-resolved measurements of soft x rays using transmission grating spectrometers at the Nike Laser Facility

    International Nuclear Information System (INIS)

    Accurate simulation of pellet implosions for direct drive inertial confinement fusion requires benchmarking the codes with experimental data. The Naval Research Laboratory (NRL) has begun to measure the absolute intensity of radiation from laser irradiated targets to provide critical information for the radiatively preheated pellet designs developed by the Nike laser group. Two main diagnostics for this effort are two spectrometers incorporating three detection systems. While both spectrometers use 2500 lines/mm transmission gratings, one instrument is coupled to a soft x-ray streak camera and the other is coupled to both an absolutely calibrated Si photodiode array and a charge coupled device (CCD) camera. Absolute calibration of spectrometer components has been undertaken at the National Synchrotron Light Source at Brookhaven National Laboratories. Currently, the system has been used to measure the spatially integrated soft x-ray flux as a function of target material, laser power, and laser spot size. A comparison between measured and calculated flux for Au and CH targets shows reasonable agreement to one-dimensional modeling for two laser power densities

  9. Absolute measurements of the 235U and 238U fission cross-sections in the 252Cf fission neutron spectrum

    International Nuclear Information System (INIS)

    Absolute measurements have been made of the fission cross-sections of 235U and 238U in the 252Cf fission neutron spectrum, using the method of coincidences between fission events in a target made of the isotope studied, and the associated fission fragments of californium. A detailed description of the measurement method is provided, covering the reasons for choosing the geometrical conditions of the experiment, the calculations made for that purpose, the preparation of targets, the detection apparatus and sources of errors. 235U and 238U fission cross-sections in the 252Cf fission neutron spectrum are calculated from differential fission cross-section measurements. (author)

  10. Functional requirements document for measuring emissions of airborne radioactive materials

    International Nuclear Information System (INIS)

    This document states the general functional requirements for systems and procedures for measuring emissions of airborne radioactive materials from facilities administered by the Westinghouse Hanford Company (WHC). The following issues are addressed in this document: lg-bullet definition of the program objectives lg-bullet selection of the overall approach to collecting the samples lg-bullet sampling equipment design lg-bullet sampling equipment maintenance and quality assurance issues. The following issues are not addressed in this document: lg-bullet air sampling in work areas or containments lg-bullet selection of specific on-line sample monitoring instrumentation lg-bullet analyzing collected samples lg-bullet reporting and interpreting results. The document provides equipment design guidance that is performance based rather than prescriptive. Locations from which samples are obtained should exhibit mixing of the contaminants with the airstream and acceptable air flow characteristics. Sample collection equipment and effluent and sample flow elements should meet defined performance standards. Quality control and assurance requirements specific to sample collection, equipment inspection, and calibration are presented. Key sample collection performance requirements are summarized in Section 5.4. The intent of this document is to assist WHC in demonstrating a high quality of air emission measurements with verified system performance based on documented system design, testing, inspection, and maintenance

  11. Methods and instrumentation for measurement of radioactive waste

    International Nuclear Information System (INIS)

    Full text: According to nuclear legislation of Ukraine radioactive waste (RAW) by acceptance for disposal (storage), data about radioisotope contents of waste, specific and total activity of each important radionuclide have to be noted into Raw index card for the purpose of its certification. New requirements stimulate the elaboration of methods and spectrometric devices for certification of RAW, which can ensure reliability and necessary accuracy of the values being measured. The report represents a survey of methods for determination of radionuclide contents and specific activity of RAW. The methods are based on measurement of exposure rate on the surface of RAW container or package and on analysis of gamma spectra from volumetric sources. A method of calibration of gamma-spectrometers for determination of specific activity of RAW developed by the authors is offered. The method is suitable for scintillation and semiconductor detectors. Calibration coefficients are got in laboratory conditions using point standard sources, which are later used for software calculation of specific activity of radionuclides in RAW. Material and density of RAW matter, dimensions and material of container or package are also taken into account by calculation. The method is tested in real conditions on Rivnenska NPP. A problem of application of spectrometry equipment for RAW certification is considered, as well as software, which is used for acquisition and analysis of gamma-spectra. (author)

  12. A twin type heat flow microcalorimeter for radioactivity measurements

    International Nuclear Information System (INIS)

    A microcalorimeter is described which was developed and tested for measuring the activity of pure ? particle emitters. Two identically made calorimeter cells are used, each 46.5 mm i.d. and 54.0 mm deep and each fitted with thermomodules generating an emf of about 29 mV deg C-1. The thermal energy from the cells flows into a surrounding mass of aluminium (15 kg) embedded in 30 mm thick styrofoam. The entire assembly is then immersed into an open thermostated bath controlled by electric heaters an arrangement which facilitates acces for sample changing. The outputs of the modules (sensors) are connected in opposing polarities, the net output being amplified and this voltage signal is used to estimate the radioactivity in the samples. In order to demonstrate usefulness of this calorimeter, approximately 3.7 GBq(100 mCi) of tritiated water was measured. The result was compared with that of liquid scintillation counting method and found to be agreed within 5%. (author)

  13. On the calculation of the average in radioactivity measurements

    International Nuclear Information System (INIS)

    Three different methods for averaging the independent experimental results in radioactivity measurements are compared by using computer simulation. The first method is newly introduced according to the maximum likelihood method. The second and third methods are the conventional simplest arithmetic and weighted means, respectively. The parent mean of the net counts per unit time, ?, is assumed to be identical in two measurements and the parent means of the background per unit time, ?1 and ?2, are different each other. The counting data of the sample ?? (?=1, 2), are generated by the Poisson random number generator, whose parent means are of (?+??)t?, respectively, where t? are the accumulation periods of the sample measurements. The background data are also generated with the parent means, ???? (?=1, 2), where ?? are the accumulation periods of the background. The generated data are analysed by the different three methods. In the new method, one can get non-linear simultaneous equations by differentiating the likelihood function with respect to ?, ?1 and ?2. The simultaneous equation can be solved by a successive approximation, and then the estimate of ? can be obtained. The simplest arithmetic mean is carried out for the sample counts per unit time subtracted by the backgrounds per unit time. The weighted mean is done in the same manner as the case of the Gaussian-distributed data. These processes are repeated 10,000 or 20,000 times and the arithmetic means of three estimates are independently calculated according to the methods. The new method and the simplest arithmetic mean denote the similar results, and give good estimates of the parent means, ?. The weighted mean does not give good estimates. The new method is most desirable for the analysis, if all of the original data in measurement are known. (J.P.N.)

  14. Measurement of natural radioactivity of the leaf Nefza (Oued belif)

    International Nuclear Information System (INIS)

    Nefza region, specifically Oued Belif, has a unique geological diversity in Tunisia. That's why it was chosen to be a study of natural radioactivity. The results were encouraging and have allowed us to draw conclusions about the origin of the high natural radioactivity found in certain rocks.

  15. The Comparison of Absolute Dose due to Differences of Measurement Condition and Calibration Protocols for Photon Beams

    International Nuclear Information System (INIS)

    The absolute absorbed dose can be determined according to the measurement conditions; measurement material, detector, energy and calibration protocols. The purpose of this study is to compare the absolute absorbed dose due to the differences of measurement condition and calibration protocols for photon beams. Dosimetric measurements were performed with a farmer type PTW and NEL ionization chambers in water, solid water, and polystyrene phantoms using 6 MV photon beams from Siemens linear accelerator. Measurements were made along the central axis of field size for constant target to surface distance of 100 cm for water, solid water and polystyrene phantom. Theoretical absorbed dose intercomparisons between TG21 and IAEA protocol were performed for various measurement combinations on phantom, ion chamber, and electrometer. There were no significant differences of absorbed dose value between TG2l and IAEA protocol. The differences between two protocols are within 1% while the average value of IAEA protocol was 0.5% smaller than TG2l protocol. For the purpose of comparison, all the relative absorbed dose were normalized to NEL ion chamber with Keithley electrometer and water phantom, The average differences are within 1%, but individual discrepancies are in the range of -2.5% to 1.2% depending upon the choice of measurement combination. The largest discrepancy of -2.5% was observed when NEL ion chamber with Keithley electrometer is used in solid water phantom. The main cause for this discrepancy is due to the use of same parameters of stopping power, absorption coefficient, etc. as used in water phantom. It should be mentioned that the solid water phantom is not recommended for absolute dose calibration as the alternative of water, since absorbed dose show some dependency on phantom material other than water. In conclusion, the trend of variation was not much dependent on calibration protocol. However, It shows that absorbed dose could be affected by phantom material other than water.

  16. Measurements of radioactive and xenobiotic substances in the biosphere in the Netherlands 1982

    International Nuclear Information System (INIS)

    In this annual report the results and conclusions are given of measurements of radioactive and xenobiotic substances in the biosphere of the Netherlands. The measurements are coordinated by the Coordinating Committee for the Monitoring of Radioactive and Xenobiotic Substances (CCRX). (Auth.)

  17. Measurements of single and double spin asymmetry in proton-proton elastic scattering. Using RHIC polarized proton beam absolute polarimeter

    International Nuclear Information System (INIS)

    Novel information on nucleon spin structure has been reported one after another from RHIC spin program. In this paper, an overview of the absolute polarimeter, which is referred to by all results of the experiment groups, is presented. Experiment of the precise measurement of spin asymmetry of proton-proton elastic scattering, which supports the principle of the polarimeter, is also presented. In addition, recent experimental information of the spin dependence of nuclear force in the region where momentum transfer is too small to apply perturbative QCD is reported. The absolute polarimeter is designed for two objectives. The first is to supply the polarization officially to the experiment groups of PHENIX and STAR. The second is to study the origin of single and double spin asymmetry AN and ANN. The RHIC accelerator is reviewed with an illustration from the viewpoint of polarized neutron beam. Set up of the absolute polarimeter and event identification of elastic scattering are illustrated. Back ground is discussed briefly. Result of AN is presented. Finally measurements of beam polarization and ANN are discussed. (S. Funahashi)

  18. Absolute nuclear material assay

    Science.gov (United States)

    Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  19. Measurents of natural radioactivity in an underground hydroelectric power plant

    International Nuclear Information System (INIS)

    In underground working places, especially when ventilation is not properly regulated, large amounts of natural radioactivity can be found. This can give rise to potential exposures of non-negligible magnitude. Direct measurements of gamma radiation and radon were carried out during excavation works for the construction of an hydroelectric plant in the north of Italy. After the construction of the plant, in order to reduce radon concentrations and to improve ventilation effectiveness, the main entry gate was motorized and automated. Then, in order to find the optimal speed for the fans located in the galleries and in the power plant, radon and airflow velocity were measured. Correlation data between airflow and radon concentrations were found. An automatic regulation system has been set up using air velocity detectors and slightly modifying the software for the control and regulation of the power plant. Measurements must be made in order to identify radon sources and evaluate quantitative contributions as a function of ventilation. Underground hydroelectric plants are provided with entry galleries as well as secondary galleries from which radon coming out from the soil and the walls can exhale in quantities that depend on the contents of 226Ra in the rocks and in the building materials. Other radon sources are the water coming out from the walls of the galleries and the water in the deep well located at the bottom of the power plant. Geological studies and mathematical models are useful means for the analysis of the relative contributions of the main sources as well as for the prediction of the effects deriving from modifications of the hydroelectric plant ventilation system or resulting from other important structural changes. (author)

  20. A measurement to analyze the relative change in the Absolute Parity of Power Purchase: An application to the European Union

    OpenAIRE

    Feijoo, Santiago Rodriguez; Caro, Alejandro Rodriguez; Correa, Carlos Gonzalez

    2003-01-01

    In the present paper an index to measure the changes in the Absolute Purchasing Power Parity. in the short term of a group of territories that conform an unique market, using the information of the Harmonized Index of Consumer Prices and the Exchange Rates. This measurement is utilized to study the change in relative prices of the countries of the European Union for the period 1991-2002, and the fulfillment of the theory of the Relative Purchasing Power Parity, taking as a reference the Absol...

  1. Measurement of intrinsic radioactivity in a GSO crystal

    CERN Document Server

    Wang, S C; Fujiwara, M

    2002-01-01

    Scintillating crystal detectors offer potential advantages in low-energy low-background experiments for particle physics and astrophysics. The GSO crystal is an interesting detector to explore in future neutrino physics experiments. The contributions to background due to the various channels of intrinsic radio isotopes from the sup 2 sup 3 sup 2 Th and sup 2 sup 3 sup 8 U series are identified and studied with time-correlation analysis and detailed fits to the spectral shape. Good agreement is achieved between measured and simulated spectra, indicating that background suppression factors to the 10 sup - sup 2 -10 sup - sup 3 level are possible. The procedures can be adopted for background understanding and suppression in other low-count-rate experiments where the dominant source of background is from internal radioactivity. Based on 1656 h of data taking, limits on the double beta decay half-life for the various channels in sup 1 sup 6 sup 0 Gd are derived. The limits for the neutrinoless and the Majoron mode...

  2. Analysis of bleeding saps and radioactive measurements of deciduous trees

    International Nuclear Information System (INIS)

    Samples of bleeding sap of Betula pendula Roth, Betula lutea L., Betula papyrifera L., Betula mandshuria L., Salix mielichoferi Saut., Cornus florida L., Evodea velutina L., Vitis amurensis L., Acer tartaricum L., Aesculus parviflora L., and Juglans regia L. in the botanical garden in Graz have been collected during springs of 1987, 1988, and 1989. After a special treatment (ion-exchange and freeze-drying) the bleeding saps have been searched for the compounds of sugars, amino acids and organic acids by gas-chromatrography. LAMMA-spectra showed the ion composition, and radioactivity measurements on leaves of the trees have also been made. In all bleeding saps sugars could be identified in various concentrations, mainly glucose and fructose. All trees showed nearly the same acid spectrum, and the most common ingredient was malic acid. In the bleeding saps of the Betulaceae and Juglans regia the major constituent was citrulline. In Acer tartaricum allantoine was present in large concentration. In Evodea velutina, Aesculus parviflora, Vitis amurensis and Cornus florida glutamin could be identified in large concentration. After the reactor accident of Tschernobyl in April 1986 the number of synthetic radionuclides increased and they could be identified. The LAMMA-spectra showed high contents of kalium and calcium in the bleeding saps. (author)

  3. Results of radioactivity measurements in French coastal waters during 1985

    International Nuclear Information System (INIS)

    Various sampling networks for the environmental monitoring of levels from radioactive waste releases from french nuclear plants have been set up by the Departement de Protection Sanitaire (DPS) since 1983. In 1985, various marine and freshwater biological indicators were collected regularly on the Channel, Atlantic and Mediterranean shores and at the level of the lower Rhone river. As in the previous years, the results showed the prevailing effects of the releases from the LA HAGUE reprocessing plant on the Channel and of the Rhone waters on the Mediterranean sea. Measurements at the level of the lower Rhone showed a clear labelling of the Rhone river waters by 106Ru. The monitoring of ruthenium levels in various biological indicators from the Mediterranean shore supplied a good representation of the marine areas affected by the Rhone river. At the stations with the highest levels, the sanitary consequence of man-made radionuclides remained low, representing a fraction in the range of 10-5 of the dose limit recommended by the International Commission on Radiological Protection

  4. Absolute measurements of the alpha-gamma emitters activities by a sum-coincidence method

    International Nuclear Information System (INIS)

    The absolute activity of U-235 contained in a UO2 sample, using a sum-coincidence circuit which selected only the alpha particles which were simultaneous with the well known 184 Kev gamma radiation from Th-231. The alpha particles were detected by ZnS(Ag) scintillator specially designed to show its maximun efficiency for U-235 alpha particles, whereas the gamma radiation was detected by NaI(Tl) scintillation detector. The values obtained for the half-life of U-235 was compared with data from various observers using different experimental techniques. (Author)

  5. Absolute measurements of the fast neutron flux in the reactor RA

    International Nuclear Information System (INIS)

    The absolute neutron flux in the vertical VK-5 hole of the reactor RA was determined by using the 27Al (n, alpha) 24Na reaction, and by counting the 24Na - 2.5 MeV gamma line photopeak activity. A method for the determination of ?eff as a mean value between the two large limiting cases of neutron spectra is used. The flux at the power level of 5 MW was found to be (2.5±0.9)·1012n/cm2sec (author)

  6. Measurements of absolute M-subshell X-ray production cross sections of Th by electron impact

    International Nuclear Information System (INIS)

    Highlights: • The M X-ray production cross sections of Th were measured by electron impact. • The M-subshell ionization cross sections of Th were determined from 3 to 38 keV. • Theoretical ionization cross-sections are in agreement with our experimental results. - Abstract: Measurements of absolute M-subshell X-ray production cross sections for element Th were made by electron impact for energies ranging from the ionization threshold up to 38 keV. Experimental data were obtained by measuring the X-ray intensity emitted from ultrathin Th films deposited onto self-supporting C backing films. The measurements were conducted with an electron microprobe using high-resolution wavelength dispersive spectrometers. Recorded intensities were converted into absolute X-ray production cross sections by means of atomic data and estimation of the number of primary electrons, target thickness, and detector efficiency. Our experimental X-ray production cross sections, the first to be reported for the M subshells of Th, are compared with X-ray production cross sections calculated with the mean of ionization cross sections obtained from the distorted-wave Born approximation. The M? X-ray production cross section calculated is in excellent agreement with the measurements, allowing future use for standardless quantification in electron probe microanalysis

  7. Calibration of new measuring systems to detect emissions of radioactive noble gases

    International Nuclear Information System (INIS)

    This report describes the calibration of different systems for the integral measurement of radioactive noble gases and the calibration of a measuring chamber for the detection of individual nuclides of radioactive noble gases in the gaseous effluent of nuclear power plants. For these measuring chambers the calibration factors for Kr-85 and Xe-133 are given as well as the detection limits to be obtained with these measuring systems for several radioactive noble gases present in the gaseous effluent at the stack of nuclear power plants. Calibration factors for Kr-85 and Xe-133 and the detection limits of this measuring method for the detections of individual nuclides of radioactive noble gases in air samples are defined taken wirh a high pressure compressor in pressure flasks an measured on a Ge(Li)-semiconductor spectrometer (pressure flask measuring method). A measuring equipment is described and calibrated which allows simultaneous measurement of activity concentration of radioactive noble gases and radioactive aerosols with a sensitivity of 2 x 10-7 Ci/m3 for radioactive gases and 1 x 10-9 Ci/m3 for radioactive particulates at a background radiation of 1 R/h. This paper is an additional report to our STH-Bericht 3/76, 'Calibration of measuring equipment for monitoring of gaseous effluents from nuclear power plants', which specifies a procedure for the calibration of measuring chambers for monitoring of gaseous radioactive effluents from nuclear power plants /1/. The calibration system used here makes it possible to simultaneously calibrate several noble gas measuring devices. (orig.)

  8. Measurement of absolute gamma-ray emission probabilities from decay of 138Xe

    International Nuclear Information System (INIS)

    The fission gaseous 138Xe products play an important role in the research of nuclear-reaction products and radioisotope applications. Therefore, precise data for emission probabilities of gamma-ray from decay of 138Xe are highly desired. However, a high precision is not achievable with a sufficient accuracy due to the limitations of the usual experimental techniques. In this paper, after the homogeneous sources of 138Xe–138Cs were prepared, the activity of 138Xe was obtained by the decay relationship between 138Xe and 138Cs using a HPGe detector. The full-energy peak efficiencies of gamma-ray for 138Xe and 138Cs were accurately calibrated using many activity standard sources and self-absorption was corrected. As a result, the absolute emission probabilities of the 258.4, 434.6 and 1768.3 keV gamma-ray from decay of 138Xe were determined to be 34.9(10)%, 22.2(6)% and 18.8(5)%, respectively. - Highlights: • The activity of 138Xe was obtained by the decay relationship between 138Xe and 138Cs. • The full-energy peak efficiencies of gamma-ray for 138Xe and 138Cs were accurately calibrated. • The absolute gamma-ray probabilities from decay of 138Xe were determined

  9. Absolute optical frequency measurements of Cs two-photon transitions with a femtosecond frequency comb

    Science.gov (United States)

    Mbele, Vela L.; Stalnaker, Jason E.; Gerginov, Vladislav; Fortier, Tara; Tanner, Carol E.; Diddams, Scott A.; Hollberg, Leo

    2007-03-01

    We study by direct excitation with a mode-locked femtosecond optical frequency comb, multiple transitions in Cs atoms in a vapor cell at room temperature. We improve by up to two orders of magnitude the uncertainties in the absolute optical frequency and hyperfine structure of the 6s ^2 S1/2->8s ^2 S1/2,9s ^2 S1/2, and 7d ^2 D3/2,5/2 transitions in ^133Cs. Cesium is one of the well studied heavy atoms, with atomic structure calculations on the order of 1%, and has provided a fertile testbed for fundamental tests of atomic theory and QED. This work reports on a simple and novel experimental approach that allows simultaneous recording of multiple transition frequencies. Atoms in a vapor cell at room temperature have a broad Doppler velocity distribution which allow selective excitation by discrete modes of a mode-locked femtosecond comb. This, in turn, results in stepwise multiphoton resonant transitions in the atoms. We model the collected spectra using a standard 2? formula and use least square fitting routines to extract improved values of absolute optical frequencies and coupling constants.

  10. Measurement of absolute CO number densities in CH3F/O2 plasmas by optical emission self-actinometry

    International Nuclear Information System (INIS)

    CH3F/O2 inductively coupled plasmas at 10 mTorr were investigated using optical emission spectroscopy. A ‘self-actinometry’ method was developed to measure the absolute number density of CO that formed in reactions following dissociation of CH3F and O2 in the plasma. In this method, small amounts of CO were added to the plasma, leading to small increases in the CO emission intensity. By carefully accounting for small perturbations to the plasma electron density and/or electron energy distribution, and by showing that very little of the CO added to the plasma was decomposed by electron impact or other reactions, it was possible to derive absolute number densities for the CO content of the plasma. With equal fractions (0.50) of CH3F and O2 in the feed gas, the CO mole fraction as a function of plasma power saturated at a value of 0.20–0.25. As O2 in the feed gas was varied at a constant power of 100 W, the CO mole fraction went through a maximum of about 0.25 near an O2 feed gas fraction of 0.5. The relative CO number densities determined by ‘standard’ actinometry followed the same functional dependence as the absolute mole fractions determined by self-actinometry, aided by the fact that electron temperature did not change appreciably with power or feed gas composition. (paper)

  11. Measurement of absolute radical densities in a plasma using modulated-beam line-of-sight threshold ionization mass spectrometry

    International Nuclear Information System (INIS)

    Using modulated beam line-of-sight threshold ionization mass spectrometry (LOS-TIMS) we measured absolute O, O2, and Ar densities, and the average neutral-gas temperature in an O2/Ar electrical discharge as a function of pressure in the plasma chamber and the mole fraction of Ar in O2; the pressure and mole fraction range was 25-200 mTorr and 0-0.90, respectively. Although LOS-TIMS is a versatile tool for measuring absolute radical densities, it requires careful vacuum design and calibration to account for various sources of error such as the contribution to the quadrupole mass spectrometer (QMS) ion current from the background gases, the ion mass-to-charge ratio dependent sensitivity of the various QMS components, and space-charge limitations in the QMS ionizer. In addition, collisions within the molecular beam extracted from the discharge must be taken into account particularly for higher plasma chamber pressures (>75 mTorr). In our measurements, these effects are carefully considered and the consequences of ignoring them are discussed. The O atom density increases with pressure and O2 mole fraction in the feed gas and is in the range of 2.1x1018-2.6x1019 m-3. At low pressures, our measurements show that the O2 translational temperature is higher than that for Ar

  12. Measurements of Natural Radioactivity in Submicron Aerosols in Mexico City.

    Science.gov (United States)

    Gaffney, J. S.; Marley, N. A.; Sterling, K.; Sturchio, N. C.

    2003-12-01

    Natural radionuclides can be useful in evaluating the transport of ozone and aerosols in the troposphere. Beryllium-7, which is produced by cosmic ray interactions in the upper troposphere and lower stratosphere and becomes adsorbed on fine aerosols, can be a useful indicator of upper air transport into a region. Lead-210 is produced by the decay of radon-222 out-gassed into the lower atmosphere from ground-based uranium deposits. Potassium-40, found in soils, can act as a measure of wind-blown dust and also comes from burning of wood and other biomass that is enriched in this natural radioisotope. Thus, both lead-210 and potassium-40 can aid in identification of aerosols sourced in the lower atmosphere. As part of our continuing interest in the lifetimes and sources of aerosols and their radiative effects, we report here measurements of fine aerosol radioactivity in Mexico City, one of the largest megacities in the world. Samples were collected on quartz fiber filters by using cascade impactors (Sierra type, Anderson Instruments) and high-volume air samplers from the rooftop of the main laboratory of El Centro Nacional de Investigacion y Capacitacion Ambiental (CENICA). By using stage 4 of the impactor and timers, we were able to collect integrated samples of sizes > 1 micrometer and < 1 micrometer over 12-hr time periods daily for approximately one month in April 2003. Samples were counted at the University of Illinois at Chicago by using state-of-the-art gamma counting (beryllium-7, 477.6 keV; potassium-40, 1460.8 keV; lead-210, 46.5 keV). The beryllium-7 data indicate one possible upper-air transport event during April 2003. As expected, the lead-210 data indicate very little soil contribution to the fine aerosol. The potassium-40 data showed an increase in fine aerosol potassium during Holy Week that might be attributed to local combustion of biomass fuels. The data will be presented and discussed in light of future data analysis and comparison with other measurements taken during the study. The authors wish to thank the researchers at CENICA. This work was supported by the U.S. Department of Energy, Atmospheric Science Program. We also wish to acknowledge Drs. Mario and Luisa Molina for their help in organizing and directing the Mexico City Metropolitan Area 2003 field study, during which these data were collected.

  13. Measurement of absolute left ventricular volume by radionuclide angiography: a technical review

    International Nuclear Information System (INIS)

    Absolute left ventricular volumes have important clinical implications in the evaluation of cardiac performance. Several invasive and noninvasive techniques have been reported, none of which can be considered ideal for this purpose. Contrast angiography, echocardiography and radionuclide ventriculography are open to criticism. Different radioisotopic approaches are described with emphasis on the importance of accurate separation of left ventricular activity, the selection of background activity, and the correction for photon attenuation by body tissues. Improper use of statistics and validation techniques have obscured the value of these techniques. In the absence of a 'gold standard' there should be a 'radioisotopic' left ventricular volume with established independent characteristics, repeatability and reproducibility by which new approaches can be judged. (author)

  14. 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

  15. The lessons learnt from a series of radioactivity measurement intercomparison exercises

    International Nuclear Information System (INIS)

    Over the past decade, the National Physical Laboratory (NPL) has run a number of intercomparison exercises, aimed at those laboratories making measurements of radioactivity at environmental levels. The need for such intercomparisons were initially driven by the Chernobyl accident and it's aftermath. Immediately after the accident, many measurements were made of radioactivity in the UK environment, but the lack at that time of a coordinated programme of measurements, feeding into a dissemination centre did nothing to improve public confidence in such measurements. This situation was remedied by the Department of the Environment (DoE) in the years following Chernobyl. In the longer term this perceived (and in most cases, undeserved) lack of public confidence in 'official' data led many laboratories in the UK, with no statutory need to measure radioactivity, to equip themselves to be able to make measurements of radioactivity in food and other environmental materials

  16. Measurements of the Absolute Branching Fractions of B^\\pm --> K^\\pm X_{c\\bar c}

    CERN Document Server

    Aubert, B; Abrams, G S; Adye, T; Ahmed, M; Ahmed, S; Alam, M S; Albert, J; Aleksan, Roy; Allen, M T; Allison, J; Allmendinger, T; Altenburg, D; Andreassen, R; Andreotti, M; Angelini, C; Anulli, F; Arnaud, N; Aston, D; Azzolini, V; Baak, M; Back, J J; Baldini-Ferroli, R; Band, H R; Banerjee, S; Barate, R; Bard, D J; Barlow, N R; Barlow, R J; Barrett, M; Bartoldus, R; Batignani, G; Battaglia, M; Bauer, J M; Beck, T W; Behera, P K; Bellini, F; Benayoun, M; Benelli, G; Berger, N; Bernard, D; Berryhill, J W; Best, D; Bettarini, S; Bettoni, D; Bevan, A J; Bhimji, W; Bhuyan, B; Bianchi, F; Biasini, M; Biesiada, J; Blanc, F; Blaylock, G; Blinov, A E; Blinov, V E; Bloom, P; Bomben, M; Bondioli, M; Bonneaud, G R; Bosisio, L; Boutigny, D; Bowerman, D A; Boyarski, A M; Boyd, J T; Bozzi, C; Brandenburg, G; Brandt, T; Brau, J E; Breon, A B; Briand, H; Brose, J; Brown, C L; Brown, C M; Brown, D; Brown, D N; Bruinsma, M; Brunet, S; Bucci, F; Buchanan, C; Buchmüller, O L; Bugg, W; Bukin, A D; Bula, R; Bulten, H; Burchat, P R; Burke, J P; Button-Shafer, J; Buzzo, A; Bóna, M; Cahn, R N; Calabrese, R; Calcaterra, A; Calderini, G; Campagnari, C; Capra, R; Carpinelli, M; Cartaro, C; Cavallo, N; Cavoto, G; Cenci, R; Chai, X; Chaisanguanthum, K S; Chao, M; Charles, E; Charles, M J; Chauveau, J; Chavez, C A; Chen, A; Chen, C; Chen, E; Chen, J C; Chen, S; Chen, X; Cheng, B; Cheng, C H; Chevalier, N; Cibinetto, G; Clark, P J; Claus, R; Cochran, J; Coleman, J P; Contri, R; Convery, M R; Cormack, C M; Cossutti, F; Cottingham, W N; Couderc, F; Covarelli, R; Cowan, G; Cowan, R; Crawley, H B; Cremaldi, L; Cristinziani, M; Cunha, A; Curry, S; Côte, D; D'Orazio, A; Dahmes, B; Dallapiccola, C; Danielson, N; Dasu, S; Datta, M; Dauncey, P D; David, P; Davier, M; Davis, C L; Day, C T; De Groot, N; De Nardo, Gallieno; De Sangro, R; Del Buono, L; Del Re, D; Della Ricca, G; Di Lodovico, F; Di Marco, E; Dickopp, M; Dingfelder, J C; Dittongo, S; Dong, D; Dorfan, J; Druzhinin, V P; Dubitzky, R S; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Dvoretskii, A; Eckhart, E A; Eckmann, R; Edgar, C L; Edwards, A J; Egede, U; Eichenbaum, A M; Eigen, G; Eisner, A M; Elmer, P; Emery, S; Ernst, J A; Eschenburg, V; Eschrich, I; Eyges, V; Fabozzi, F; Faccini, R; Fan, S; Feltresi, E; Ferrarotto, F; Ferroni, F; Field, R C; Finocchiaro, G; Flacco, C J; Flack, R L; Flächer, H U; Flood, K T; Ford, K E; Ford, W T; Forster, I J; Forti, F; Fortin, D; Foulkes, S D; Franek, B; Frey, R; Fritsch, M; Fry, J R; Fulsom, B G; Gabathuler, E; Gaidot, A; Gaillard, J R; Galeazzi, F; Gallo, F; Gamba, D; Gamet, R; Gan, K K; Ganzhur, S F; Gary, J W; Gaspero, M; Gatto, C; George, K A; Gill, M S; Giorgi, M A; Giroux, X; Gladney, L; Glanzman, T; Godang, R; Goetzen, K; Golubev, V B; Gopal, G P; Gowdy, S J; Gradl, W; Graham, M; Grancagnolo, S; Graugès-Pous, E; Graziani, G; Green, M G; Grenier, P; Gritsan, A V; Grosdidier, G; Groysman, Y; Guo, Q H; Hadavand, H K; Hadig, T; Haire, M; Halyo, V; Hamano, K; Hamel de Monchenault, G; Hamon, O; Harrison, P F; Harrison, T J; Hart, A J; Hartfiel, B L; Hast, C; Hauke, A; Hawkes, C M; Hearty, C; Held, T; Hertzbach, S S; Heusch, C A; Hill, E J; Hirschauer, J F; Hitlin, D G; Hodgkinson, M C; Hollar, J J; Hong, T M; Honscheid, K; Hopkins, D A; Hrynóva, T; Hufnagel, D; Hulsbergen, W D; Hutchcroft, D E; Höcker, A; Igonkina, O; Innes, W R; Izen, J M; Jackson, P D; Jackson, P S; Jacobsen, R G; Jawahery, A; Jessop, C P; John, M J J; Johnson, J R; Judd, D; Kadel, R W; Kadyk, J; Kagan, H; Karyotakis, Yu; Kass, R; Kelly, M P; Kelsey, M H; Kerth, L T; Khan, A; Kim, H; Kim, P; Kirkby, D; Kitayama, I; Klose, V; Knecht, N S; Koch, H; Kocian, M L; Koeneke, K; Kofler, R; Kolomensky, Yu G; Koptchev, V B; Kovalskyi, D; Kowalewski, R V; Kozanecki, Witold; Kravchenko, E A; Kreisel, A; Krishnamurthy, M; Kroeger, R; Kroseberg, J; Kukartsev, G; Kutter, P E; Kyberd, P; La Vaissière, C de; Lacker, H M; Lae, C K; Lafferty, G D; Lanceri, L; Lange, D J; Langenegger, U; Lankford, A J; Latham, T E; Lau, Y P; Lazzaro, A; Le Diberder, F R; Lees, J P; Legendre, M; Leith, D W G S; Lepeltier, V; Leruste, P; Lewandowski, B; Li Gioi, L; Li, H; Li, X; Libby, J; Lista, L; Liu, R; Lo Vetere, M; LoSecco, J M; Lockman, W S; Lombardo, V; London, G W; Long, O; Lou, X C; Lu, M; Luitz, S; Lund, P; Luppi, E; Lusiani, A; Lutz, A M; Lynch, G; Lynch, H L; Lü, C; Lüth, V; MacFarlane, D B; Macri, M; Mader, W F; Majewski, S A; Malcles, J; Mallik, U; Mancinelli, G; Mandelkern, M A; Marchiori, G; Margoni, M; Marks, J; Marsiske, H; Martínez-Vidal, F; Mattison, T S; Mayer, B; Mazur, M A; Mazzoni, M A; McKenna, J A; McMahon, T R; Meadows, B T; Mellado, B; Menges, W; Messner, R; Meyer, W T; Mihályi, A; Minamora, J S; Mir, L M; Mohanty, G B; Mohapatra, A K; Mommsen, R K; Monge, M R; Monorchio, D; Moore, T B; Morandin, M; Morgan, S E; Morganti, M; Morganti, S; Morii, M

    2006-01-01

    We study the two-body decays of B^\\pm mesons to K^\\pm and a charmonium state, X_{c\\bar c}, in a sample of 210.5 fb^{-1} of data from the BaBar experiment. We perform measurements of absolute branching fractions BR(B^\\pm --> K^\\pm X_{c\\bar c}) using a missing mass technique, and report several new or improved results. In particular, the upper limit BR(B^\\pm --> K^\\pm X(3872)) J/\\psi\\pi^+\\pi^-)>4.2% will help in understanding the nature of the recently discovered X(3872).

  17. Measurement of radioactive nuclides in the 'Mayak' region

    International Nuclear Information System (INIS)

    The study of environmental contamination caused by anthropogenic impact and, primarily, by radioactive nuclides is one of the main scientific problems facing contemporary science. Radioecological monitoring, decision making on remediation of polluted areas need detailed information about distribution of radioactive nuclides in the terrestrial and aquatic ecosystems, knowledge about radioactive nuclide occurrence forms and migration patterns. Experimental tests of nuclear and thermonuclear weapon in atmosphere and underground, nuclear power engineering and numerous accidents that took place at the nuclear power plants (NPP), unauthorized dump of radioactive materials in various places of the ocean and pouring off the strongly dump of radioactive wastes from ships and submarine equipped with nuclear power engines made artificial radionuclides a constant and unretrievable component of the modern biosphere, becoming an additional unfavorable ecological factor. As regards Former Sovient Union (FSU) the most unfavorable regions are Southern Ural, zones suffered from Chernobyl Accident, Altay, Novaya Zemlya, some part of West Siberia near Seversk (Tomsk-7) and Zheleznogorsk (Krasnoyarsk-26). (orig.)

  18. Measurement of radioactive nuclides in the `Mayak` region

    Energy Technology Data Exchange (ETDEWEB)

    Myasoedov, B.F. [V.I. Vernadsky Inst. of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow (Russian Federation); Novikov, A.P. [V.I. Vernadsky Inst. of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow (Russian Federation)

    1997-03-01

    The study of environmental contamination caused by anthropogenic impact and, primarily, by radioactive nuclides is one of the main scientific problems facing contemporary science. Radioecological monitoring, decision making on remediation of polluted areas need detailed information about distribution of radioactive nuclides in the terrestrial and aquatic ecosystems, knowledge about radioactive nuclide occurrence forms and migration patterns. Experimental tests of nuclear and thermonuclear weapon in atmosphere and underground, nuclear power engineering and numerous accidents that took place at the nuclear power plants (NPP), unauthorized dump of radioactive materials in various places of the ocean and pouring off the strongly dump of radioactive wastes from ships and submarine equipped with nuclear power engines made artificial radionuclides a constant and unretrievable component of the modern biosphere, becoming an additional unfavorable ecological factor. As regards Former Sovient Union (FSU) the most unfavorable regions are Southern Ural, zones suffered from Chernobyl Accident, Altay, Novaya Zemlya, some part of West Siberia near Seversk (Tomsk-7) and Zheleznogorsk (Krasnoyarsk-26). (orig.)

  19. Surveillance of radioactivity in the atmosphere between prognosis and measurement - early alert in the Deutscher Wetterdienst

    International Nuclear Information System (INIS)

    The Deutscher Wetterdienst (DWD) 'German Meteorological Service' is legally responsible for the large-scale surveillance of radioactivity in the atmosphere. For an early alert of artificial radioactivity gamma-ray-spectrometry of aerosols is performed at selected meteorological stations of the synoptic-climatological network. Results of measurements as well as dispersion calculations are urgently required for making further decisions. The combination of measurements and forecasts combined with airborne measurements in an alert-situation is discussed. (orig.)

  20. Effect of self-vibration on accuracy of free-fall absolute gravity measurement with laser interferometer

    Science.gov (United States)

    Feng, Jin-yang; Wu, Shu-qing; Li, Chun-jian; Su, Duo-wu; Yu, Mei

    2015-02-01

    A free-fall absolute gravimeter was used to measure the gravity acceleration of a corner-cube released in high vacuum, and the gravity acceleration was determined by fitting the free-falling trajectories obtained through optical interferometry. During the measurement, the self-vibration of an absolute gravimeter caused ground vibration and the change in optical path length due to vibration of vacuum-air interface, which resulted in a measurement error. Numerical simulation was run by introducing vibration disturbance to the trajectories of free-fall. The effect of disturbance under different instrumental self-vibration conditions was analyzed. Simulation results indicated that the deviation of calculated gravity acceleration from the preset value and residuals amplitude after fitting depended on the amplitude and initial phase of the vibration disturbance. The deviation value and fitting residuals amplitude increased with the increasing of amplitude and there was a one-to-one correspondence between the two. The deviation of calculated gravity acceleration decreases by properly setting the initial phase difference of vibration disturbance with respect to the interference fringe signal.

  1. A Novel Portable Absolute Transient Hot-Wire Instrument for the Measurement of the Thermal Conductivity of Solids

    Science.gov (United States)

    Assael, Marc J.; Antoniadis, Konstantinos D.; Metaxa, Ifigeneia N.; Mylona, Sofia K.; Assael, John-Alexander M.; Wu, Jiangtao; Hu, Miaomiao

    2015-08-01

    A new portable absolute Transient Hot-Wire instrument for measuring the thermal conductivity of solids over a range of 0.2 W{\\cdot }m^{-2}{\\cdot }K^{-1} to 4 W{\\cdot }m^{-1}{\\cdot }K^{-1} is presented. The new instrument is characterized by three novelties: (a) an innovative two-wires sensor which provides robustness and portability, while at the same time employs a soft silicone layer to eliminate the effect of the contact resistance between the wires and the sample, (b) a newly designed compact portable printed electronic board employing an FPGA architecture CPU to the control output voltage and data processing—the new board replaces the traditional, large in size Wheatstone-type bridge system required to perform the experimental measurements, and (c) a cutting-edge software suite, developed for the mesh describing the structure of the sensor, and utilizing the Finite Elements Method to model the heat flow. The estimation of thermal conductivity is modeled as a minimization problem and is solved using Bayesian Optimization. Our revolutionizing proposed methodology exhibits radical speedups of up to × 120, compared to previous approaches, and considerably reduces the number of simulations performed, achieving convergence only in a few minutes. The new instrument was successfully employed to measure, at room temperature, the thermal conductivity of two thermal conductivity reference materials, Pyroceram 9606 and Pyrex 7740, and two possible candidate glassy solids, PMMA and BK7, with an absolute low uncertainty of 2 %.

  2. Application of the permeation to the production of low radioactive calibrated gas flows. Low radioactive tritium measurement

    International Nuclear Information System (INIS)

    The permeation of compounds (HT, HTO, 131ICH3, and 129ICH3) through organic membranes in view of producing low radioactive calibrated gas flows has been studied. This process of which the diffusion is the main stage enables respecting certain conditions (choice of the membrane, temperature, partial pressure differential) our aims to be reached with a good accuracy. In order to measure radioactivity of tritiated standard gases, a detector was built. This detector is an Oeschger type proportional counter with a total volume of 17.4 dm3 and an useful volume of 3.9 dm3. In the conditions of operation, the background is of 1.7.10-6 I s-1 cm-3. The counter coupled with a feed-rack enables various samples to be measured and it is possible in the best conditions to detect some 10-11 ?Ci cm-3 NTP

  3. Measurement of radioactive contamination in the foodstuffs by gamma spectrometry

    International Nuclear Information System (INIS)

    The Chernobyl nuclear reactor accident in 1986, resulted in the increase of radioactive contamination at a global level. To avoid undesirable exposure to public, Pakistan like other countries imposed radioactive contamination levels on food items. Various imported/to be exported and locally purchased food items for human consumption have been analysed for gamma emitting radionuclides. Amongst the food items, special attention was focussed on the imported dry milk. In addition to naturally occurring K-40 radionuclide, small amounts of Cs-137 and Cs-134 fission products have been detected in some of the samples. The concentrations of these two fission radionuclides are presented and compared with the relevant limits. (author)

  4. Measurement of radioactivity in building materials in Serbia

    International Nuclear Information System (INIS)

    This work presents a comprehensive study of natural radioactivity in 720 building materials imported in Serbia in 2012. Radioactivity concentrations of 226Ra, 232Th and 40K in the studied samples range from -1, respectively. The maximum values of 226Ra and 232Th activity concentrations were found in zirconium mineral, while the highest 40K activity concentration was in the feldspar. Based on the obtained radionuclide concentrations, radium equivalent activity, air absorbed dose rate, annual effective dose, external and internal hazard indices, gamma and alpha index due to radon inhalation were evaluated to assess the potential radiological hazard associated with these building materials. (author)

  5. Real-time absolute frequency measurement of continuous-wave terahertz wave based on dual terahertz combs of photocarriers with different frequency spacings

    OpenAIRE

    Yasui, Takeshi; Hayashi, Kenta; Ichikawa, Ryuji; Cahyadi, Harsono; Hsieh, Yi-Da; Mizutani, Yasuhiro; Yamamoto, Hirotsugu; Iwata, Tetsuo; Inaba, Hajime; Minoshima, Kaoru

    2015-01-01

    Real-time measurement of the absolute frequency of continuous-wave terahertz (CW-THz) waves is required for characterization and frequency calibration of practical CW-THz sources. We proposed a method for real-time monitoring of the absolute frequency of CW-THz waves involving temporally parallel, i.e., simultaneous, measurement of two pairs of beat frequencies and laser repetition frequencies based on dual THz combs of photocarriers (PC-THz combs) with different frequency s...

  6. Improved absolute calibration of LOPES measurements and its impact on the comparison with REAS 3.11 and CoREAS simulations

    OpenAIRE

    Apel, W. D.; Arteaga-Velazquez, J. C.; Bähren, L.(ASTRON, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands); Bekk, K.; Bertaina, M.; Biermann, P.L.; Blümer, J.; Bozdog, H.; Brancus, I.M.; Cantoni, E.(Dipartimento di Fisica, Università degli Studi di Torino, Via Giuria 1, 10125 Torino, Italy); Chiavassa, A; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.

    2015-01-01

    LOPES was a digital antenna array detecting the radio emission of cosmic-ray air showers. The calibration of the absolute amplitude scale of the measurements was done using an external, commercial reference source, which emits a frequency comb with defined amplitudes. Recently, we obtained improved reference values by the manufacturer of the reference source, which significantly changed the absolute calibration of LOPES. We reanalyzed previously published LOPES measurements,...

  7. Low level air radioactivity measurements in Prague, Czech Republic.

    Czech Academy of Sciences Publication Activity Database

    Rulík, P.; Malá, H.; Be?ková, V.; Hölgye, Z.; Schlesingerová, E.; Sv?tlík, Ivo; Škrkal, J.

    2009-01-01

    Ro?. 67, - (2009), s. 969-973. ISSN 0969-8043 Institutional research plan: CEZ:AV0Z10480505 Keywords : atmospheric radionuclides * monitoring * low level activities Subject RIV: DL - Nuclear Waste, Radioactive Pollution ; Quality Impact factor: 1.094, year: 2009

  8. Radioactivity measurement of radon-222 and its daughters in rooms

    International Nuclear Information System (INIS)

    The airborne radioactivity inside the Puslit Gama buildings has been studied. The method used implies air filtration and filter beta counting. The calculation method and evaluation of radon-222 and its daughters is in the order of 10-1 pCi/l. (author)

  9. Measures to prevent breaches in the security of radioactive materials

    International Nuclear Information System (INIS)

    The objective of this paper, which is the result of the co-operation between the Swedish Board of Customs, the Swedish Radiation Protection Institute, the Security Police and the Swedish Nuclear Power Inspectorate, is to give an idea of the national prevention system as to illicit trafficking of nuclear materials and other radioactive sources. (author)

  10. Contribution to the measurement of absolute activity of electron capture decaying nuclides. Determination of the fluorescence yield of some elements

    International Nuclear Information System (INIS)

    The object of this work is the study of techniques of measurement of the absolute activity of electron capture nuclides. Two methods have been specially studied. Determination of the number of X rays emitted from the K shell due to the reorganization of atomic electrons following electron capture. This measurement was made with a high pressure (5 kg/cm2) 4? proportional counter. The absorption in the source and the backing were also studied. To determine the absolute activity it is necessary to know the fluorescence yield and the different capture probabilities PL and PK. When the electron capture is followed by ? emission (within the resolution time of the coincidence circuit) the activity was determined through the X-? coincidence method. In such a case it is not necessary to know the fluorescence yield and the capture probabilities. Various corrections - dead time, chance coincidences - were also studied. This method minimizes the decay scheme corrections. By applying these two methods to the following nuclides: Cr51, Mn54 and Zn65, the corresponding fluorescence yields have been determined: vanadium ?K = 0.191 ±0.002, chromium ?K = 0.262 ± 0.002 and copper ?K = 0.390 ± 0.004. (author)

  11. Quality assurance of external exposure measurement for national survey of environmental natural radioactive level

    International Nuclear Information System (INIS)

    This paper summarizes the quality assurance work of external exposure measurement for national survey of environmental natural radioactive level. It mainly introduces instrumentation used in external exposure measurement and its properties, the measurement results of three times of national in-site intercomparison, and in-site sample check results of measurement results from 29 provinces, cities and autonomous regions and Wuhan, Baotou cities

  12. Two-color laser-induced incandescence (2C-LII) technique for absolute soot volume fraction measurements in flames.

    Science.gov (United States)

    De Iuliis, Silvana; Cignoli, Francesco; Zizak, Giorgio

    2005-12-01

    A two-color version of the laser-induced incandescence (2C-LII) technique was implemented for measuring absolute soot volume fraction in flames. By using a calibrated tungsten ribbon lamp, soot peak temperatures were measured as a function of fluence at several locations in an ethylene diffusion flame by using a steeply edged laser beam profile. Above a certain fluence threshold, peak temperatures were tightly distributed just above 4000 K independent of the particle size and number density. Radial profiles of soot volume fraction were obtained and compared (not calibrated) with results from the laser extinction technique. Good agreement showed the validity of the 2C-LII technique at a controlled fluence. PMID:16353814

  13. Solid-state track recorder dosimetry device to measure absolute reaction rates and neutron fluence as a function of time

    Science.gov (United States)

    Gold, Raymond (1393 George Washington Way, Suite No. 7, P.O. Box 944, Richland, WA 99352); Roberts, James H. (1393 George Washington Way, Suite No. 7, P.O. Box 944, Richland, WA 99352)

    1989-01-01

    A solid state track recording type dosimeter is disclosed to measure the time dependence of the absolute fission rates of nuclides or neutron fluence over a period of time. In a primary species an inner recording drum is rotatably contained within an exterior housing drum that defines a series of collimating slit apertures overlying windows defined in the stationary drum through which radiation can enter. Film type solid state track recorders are positioned circumferentially about the surface of the internal recording drum to record such radiation or its secondary products during relative rotation of the two elements. In another species both the recording element and the aperture element assume the configuration of adjacent disks. Based on slit size of apertures and relative rotational velocity of the inner drum, radiation parameters within a test area may be measured as a function of time and spectra deduced therefrom.

  14. Determination of critical assembly absolute power using post-irradiation activation measurement of week-lived fission products

    International Nuclear Information System (INIS)

    The work presents a detailed comparison of calculated and experimentally determined net peak areas of longer-living fission products after 100 h irradiation on a reactor with power of ?630 W and several days cooling. Specifically the nuclides studied are 140Ba, 103Ru, 131I, 141Ce, 95Zr. The good agreement between the calculated and measured net peak areas, which is better than in determination using short lived 92Sr, is reported. The experiment was conducted on the VVER-1000 mock-up installed on the LR-0 reactor. The Monte Carlo approach has been used for calculations. The influence of different data libraries on results of calculation is discussed as well. - Highlights: • Measured and calculated net peak areas of selected longer living isotopes. • Determination of absolute reactor power. • Discrepancies between calculation and experiment. • Effect of data libraries on calculational results

  15. Measurement of radioactivity in the environment - Soil - Part 1: General guidelines and definitions

    International Nuclear Information System (INIS)

    This part of ISO 18589 specifies the general requirements to carry out radionuclides tests on soil sample, including sampling. This part of ISO 18589 is addressed to people responsible for determining the radioactivity present in soils for the purpose of radiation protection. This may concern soils from gardens and farmland, urban or industrial sites, as well as soil not affected by human activities. This part of ISO 18589 is applicable to all laboratories regardless of the number of personnel or the extent of the scope of testing activities. When a laboratory does not undertake one or more of the activities covered by this part of ISO 18589, such as planning, sampling or testing, the requirements of those clauses do not apply. This part of ISO 18589 is to be used in conjunction with other parts of ISO 18589 that outline the setting up of programmes and sampling techniques, methods of general processing of samples in the laboratory and also methods for measuring the radioactivity in soil. Its purpose is the following: - define the main terms relating to soils, sampling, radioactivity and its measurement; - describe the origins of the radioactivity in soils; - define the main objectives of the study of radioactivity in soil samples; - present the principles of studies of soil radioactivity; - identify the analytical and procedural requirements when measuring radioactivity in soil. This part of ISO 18589 is applicable if radionuclide measurements for the purpose of radiation protection are to be made in the following cases: - initial characterization of radioactivity in the environment; - routine surveillance of the impact of nuclear installations or of the evolution of the general territory; - investigations of accident and incident situations; - planning and surveillance of remedial action; - decommissioning of installations or clearance of materials. This part of ISO 18589 is not intended to cover scientific investigations of soil radioactivity and therefore does not apply to aspects of such measurements

  16. A new method for the absolute radiance calibration for UV/vis measurements of scattered sun light

    Directory of Open Access Journals (Sweden)

    T. Wagner

    2015-05-01

    Full Text Available Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds and the short wave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV/vis instruments that measure the spectrally resolved sky radiance, like for example zenith sky Differential Optical Absorption Spectroscopy (DOAS- instruments or Multi-AXis (MAX- DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method clear sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about <7%. For wavelengths below about 330 nm it is essential that the ozone column density during the measurements is constant and known.

  17. A new method for the absolute radiance calibration for UV/vis measurements of scattered sun light

    Science.gov (United States)

    Wagner, T.; Beirle, S.; Dörner, S.; Penning de Vries, M.; Remmers, J.; Rozanov, A.; Shaiganfar, R.

    2015-05-01

    Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds and the short wave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV/vis instruments that measure the spectrally resolved sky radiance, like for example zenith sky Differential Optical Absorption Spectroscopy (DOAS-) instruments or Multi-AXis (MAX-) DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method clear sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about <7%. For wavelengths below about 330 nm it is essential that the ozone column density during the measurements is constant and known.

  18. Establishment of a force balanced piston gauge for very low gauge and absolute pressure measurements at NPL, India

    International Nuclear Information System (INIS)

    National Physical Laboratory, the National Metrology Institute (NMI) of India is maintaining Primary standards of pressure that cover several decades of pressure, starting from 3.0E-06 Pa to 1.0 GPa. Among which a recent addition is a Force Balanced Piston Gauge, the non-rotating piston type, having better resolution and zero stability compared to any other primary pressure standards commercially available in the range 1.0 Pa to 15.0 kPa (abs and gauge). The characterization of this FPG is done against Ultrasonic Interferometer Manometer (UIM), the National Primary pressure standard, working in the range 1.0 Pa to 130.0 kPa (abs and diff) and Air Piston Gauge (APG), a Transfer Pressure Standard, working in the range 6.5 kPa to 360 kPa (abs and gauge), in their overlapping pressure regions covering both absolute and gauge pressures. As NPL being one of the signatories to the CIPM MRA, the Calibration and Measurement Capabilities (CMC) of both the reference standards (UIM and APG), are Peer reviewed and notified in the Key Comparison Data Base (KCDB) of BIPM. The estimated mean effective area of the Piston Cylinder assembly of this FPG against UIM (980.457 mm2) and APG (980.463 mm2) are well within 4 ppm and 10 ppm agreement respectively, with the manufacturer's reported value (980.453 mm2). The expanded uncertainty of this FPG, Q(0.012 Pa, 0.0025% of reading), evaluated against UIM as reference standard, is well within the reported value of the manufacturer, Q(0.008 Pa, 0.003% of reading) at k = 2. The results of the characterization along with experimental setup and measurement conditions (for gauge and absolute pressure measurements), uncertainty budget preparation and evaluation of measurement uncertainty are discussed in detail in this paper.

  19. Establishment of a force balanced piston gauge for very low gauge and absolute pressure measurements at NPL, India

    Science.gov (United States)

    Vijayakumar, D. Arun; Prakash, Om; Sharma, R. K.

    2012-11-01

    National Physical Laboratory, the National Metrology Institute (NMI) of India is maintaining Primary standards of pressure that cover several decades of pressure, starting from 3.0E-06 Pa to 1.0 GPa. Among which a recent addition is a Force Balanced Piston Gauge, the non-rotating piston type, having better resolution and zero stability compared to any other primary pressure standards commercially available in the range 1.0 Pa to 15.0 kPa (abs and gauge). The characterization of this FPG is done against Ultrasonic Interferometer Manometer (UIM), the National Primary pressure standard, working in the range 1.0 Pa to 130.0 kPa (abs and diff) and Air Piston Gauge (APG), a Transfer Pressure Standard, working in the range 6.5 kPa to 360 kPa (abs and gauge), in their overlapping pressure regions covering both absolute and gauge pressures. As NPL being one of the signatories to the CIPM MRA, the Calibration and Measurement Capabilities (CMC) of both the reference standards (UIM & APG), are Peer reviewed and notified in the Key Comparison Data Base (KCDB) of BIPM. The estimated mean effective area of the Piston Cylinder assembly of this FPG against UIM (980.457 mm2) and APG (980.463 mm2) are well within 4 ppm and 10 ppm agreement respectively, with the manufacturer's reported value (980.453 mm2). The expanded uncertainty of this FPG, Q(0.012 Pa, 0.0025% of reading), evaluated against UIM as reference standard, is well within the reported value of the manufacturer, Q(0.008 Pa, 0.003% of reading) at k = 2. The results of the characterization along with experimental setup & measurement conditions (for gauge and absolute pressure measurements), uncertainty budget preparation and evaluation of measurement uncertainty are discussed in detail in this paper.

  20. TU-A-12A-09: Absolute Blood Flow Measurement in a Cardiac Phantom Using Low Dose CT

    International Nuclear Information System (INIS)

    Purpose: To investigate a first pass analysis technique to measure absolute flow from low dose CT images in a cardiac phantom. This technique can be combined with a myocardial mass assignment to yield absolute perfusion using only two volume scans and reduce the radiation dose to the patient. Methods: A four-chamber cardiac phantom and perfusion chamber were constructed from poly-acrylic and connected with tubing to approximate anatomical features. The system was connected to a pulsatile pump, input/output reservoirs and power contrast injector. Flow was varied in the range of 1-2.67 mL/s with the pump operating at 60 beats/min. The system was imaged once a second for 14 seconds with a 320-row scanner (Toshiba Medical Systems) using a contrast-enhanced, prospective-gated cardiac perfusion protocol. Flow was calculated by the following steps: subsequent images of the perfusion volume were subtracted to find the contrast entering the volume; this was normalized by an upstream, known volume region to convert Hounsfield (HU) values to concentration; this was divided by the subtracted images time difference. The technique requires a relatively stable input contrast concentration and no contrast can leave the perfusion volume before the flow measurement is completed. Results: The flow calculated from the images showed an excellent correlation with the known rates. The data was fit to a linear function with slope 1.03, intercept 0.02 and an R2 value of 0.99. The average root mean square (RMS) error was 0.15 mL/s and the average standard deviation was 0.14 mL/s. The flow rate was stable within 7.7% across the full scan and served to validate model assumptions. Conclusion: Accurate, absolute flow rates were measured from CT images using a conservation of mass model. Measurements can be made using two volume scans which can substantially reduce the radiation dose compared with current dynamic perfusion techniques

  1. Measurement of tissue blood flow with diffusible radioactive indicators

    International Nuclear Information System (INIS)

    The determination of blood flow of different organs or tissues is of a great interest in the study of blood circulation. The authors relate the experience they have had in this field for the last twelve years, using the diffusible radioactive indicator technique. The theoretical bases of this technique have been excluded from this paper, which is essentially practical. Through analytical description of the works concerning myocardium, striated muscle, kidney, uterus, osseous and bronchial tissues, several interesting notions appear. First, contribution to pharmacological or functional stimulation tests is clearly illustrated by our investigation method of striated muscle. Second, the meaning of the blood flow thus determined is identical to a real nutritional capillary flow. Third, the Pertechnetate represents a very good radioactive tracer for the determination of low value blood flows, an original notion

  2. A device for fresh water sampling before radioactive measurements

    International Nuclear Information System (INIS)

    On account of the many field operations carried out by the laboratory, a water sampling device has been developed. This portable autonomous device performs in situ water filtration and concentration on ion exchange resins and activated carbon columns. The device is described and the trapping performance for 8 radionuclides is given. A comparison is made with the so-called evaporation method. The effects of the treatment of the filtrating elements on the radioactive results are studied. This sampling method is very sensitive

  3. Measures to radioactive contamination connected with nuclear power generation

    International Nuclear Information System (INIS)

    The problems on the environmental radioactivity due to nuclear power generation must be dealt with not only as the local problems in the regions around nuclear power plants but also as the environmental acitivity problems in global scale. Human security and protection are maintained by the regulation of releasing radioactive materials to the environment from all the facilities, not limited to nuclear power plants and nuclear fuel reprocessing plants, and the safety control of environmental activity. The fundamental concept of the regulation and control of environmental activity and each system taken in U.K., U.S. and Japan are described first. Next, the present status of releasing radioactivity into the air and water in the world is explained in detail and the minute data are shown for the release into water. The underground and deep ocean disposals of solid wastes are described with calculation formulae obtained so far. Since the information on the aspect of exposure of human body to natural radiation is important for comparison when the influence of artificial activity is evaluated, the survey of the natural radiation and the conditions of activity due to nuclear tests and the peaceful uses of atomic energy are described, respectively. In Japan, the special committee on environmental safety investigated the possibility of materializing the numerical guide to ''as low as practicable'', and submitted the report showing ''target dose'' in light water reactor nuclear power plants to the Atomic Energy Comission of Japan, in which the dose for whole body exposure is proposed as 5 m rem/year and that for thyroid gland exposure due to radioactive iodine as 15 m rem/year. (Wakatsuki, Y.)

  4. Measurement and dosimetry of radioactivity in the environment

    International Nuclear Information System (INIS)

    The irradiation of human beings and the biosphere by ionizing radiation from various sources has been subject to increased concern and interest, mainly due to its possible health effects. As all human beings and all other living organisms have been exposed to such radiation since the origin of life on earth, the natural radiation dose rate could be used as a yardstick when studying the biological effects of human-made radiation. This natural radiation background is caused by cosmic radiation, radiation from radionuclides in the environment, and from some radionuclides incorporated in living tissue. Of these sources radiation from environmental and internal radioactivity contributes about 85% of the average per capita global annual effective dose equivalent, which is about 2 mSv (200 mrem), a figure adopted by the United Nations Scientific Committee on the Effects of Atomic Radiation in its last report. The main reason for this 100% increase of the hitherto accepted average value 1 mSv/yr is the improved knowledge and increased concern about environmental concentration of radon and its decay products. Today considerable amounts of manufactured radioactive substances are deposited on the earth. The main sources for this contamination are fallout from nuclear weapons testing, release from nuclear power plants, and medical use of radioactive pharmaceuticals. As large populations are exposed to radiation from these sources, it is considered very important to keep these contributions at a low level and, therefore, to establish continuous supervision of the presence, concentration, and transfer to the biosphere of these radionuclides

  5. Exact method for determining subsurface radioactivity depth profiles from gamma spectroscopy measurements

    CERN Document Server

    Van Siclen, Clinton DeW

    2011-01-01

    Subsurface radioactivity may be due to transport of radionuclides from a contaminated surface into the solid volume, as occurs for radioactive fallout deposited on soil, or from fast neutron activation of a solid volume, as occurs in concrete blocks used for radiation shielding. For purposes including fate and transport studies of radionuclides in the environment, decommissioning and decontamination of radiation facilities, and nuclear forensics, an in situ, nondestructive method for ascertaining the subsurface distribution of radioactivity is desired. The method developed here obtains a polynomial expression for the radioactivity depth profile, using a small set of gamma-ray count rates measured by a collimated detector directed towards the surface at a variety of angles with respect to the surface normal. To demonstrate its capabilities, this polynomial method is applied to the simple case where the radioactivity is maximal at the surface and decreases exponentially with depth below the surface, and to the ...

  6. The measurement of radioactivity in tomatoes cultivated on mining residues from the Oka niobium mining community

    International Nuclear Information System (INIS)

    The radioactivity contained in the tailings of a niobium mine in the Oka region, Quebec, was the object of concern for the population of the area in 1979. To find the impact of these tailings on fruit and vegetables grown in this environment, an investigation of the radioactivity found on tomatoes grown in green houses in niobium tailings and in vermiculites was undertaken. The tailings contained a high level of natural radioactivity and a small amount of 137Cs while the vermiculites has a very low level of natural radioactivity and an appreciable amount of 137Cs. Cesium-137 was the only nuclide detected in tomato ashes in measurable quantity. Absence of natural radioactivity is explained by its presence as insoluble minerals. (author)

  7. Measurement of absolute thermal neutron flux density in the core of miniature neutron source reactor

    International Nuclear Information System (INIS)

    In the miniature neutron source reactor (MNSR) reactivity and neutron flux are related. A xenon poison method is proposed for measurement of thermal neutron flux density. The principle measurement condition and procedures are discussed. The precision of the method is better than that of gold foil activation method

  8. A calibration-independent laser-induced incandescence technique for soot measurement by detecting absolute light intensity.

    Science.gov (United States)

    Snelling, David R; Smallwood, Gregory J; Liu, Fengshan; Gülder, Omer L; Bachalo, William D

    2005-11-01

    Laser-induced incandescence (LII) has proved to be a useful diagnostic tool for spatially and temporally resolved measurement of particulate (soot) volume fraction and primary particle size in a wide range of applications, such as steady flames, flickering flames, and Diesel engine exhausts. We present a novel LII technique for the determination of soot volume fraction by measuring the absolute incandescence intensity, avoiding the need for ex situ calibration that typically uses a source of particles with known soot volume fraction. The technique developed in this study further extends the capabilities of existing LII for making practical quantitative measurements of soot. The spectral sensitivity of the detection system is determined by calibrating with an extended source of known radiance, and this sensitivity is then used to interpret the measured LII signals. Although it requires knowledge of the soot temperature, either from a numerical model of soot particle heating or experimentally determined by detecting LII signals at two different wavelengths, this technique offers a calibration-independent procedure for measuring soot volume fraction. Application of this technique to soot concentration measurements is demonstrated in a laminar diffusion flame. PMID:16270566

  9. Rapid measurement of 89,90Sr radioactivity in rinse water.

    Science.gov (United States)

    Masashi, Takada; Hiroko, Enomoto; Toshikazu, Suzuki

    2013-03-01

    Rapid measurement of radioactivity from Sr in aqueous solutions is performed using a technique combining a strontium rad disk and a picobeta spectrometer. Identification of Sr radionuclides is accomplished in as little as 90 min in a radiation-tainted solution that contains more highly radioactive cesium. It is possible to perform triage by assessing skin exposure doses in this short time. This simple technique could be used in mobile laboratories. Sr having 1 Bq radioactivities are measured in 10 kBq Cs in aqueous solution. The radioactivity contained in rinse water used to decontaminate the feet of workers who stepped into highly contaminated water in the basement of the turbine building of Unit 3 at the Fukushima Daiichi nuclear power station was measured. The amount of Sr radioactivity in rinse water using the authors' rapid measurement technique (0.29 Bq mL) and a traditional method agree well, with 3.6% difference. Based on this agreement, this technique is confirmed to be useful for rapid measurement of Sr radioactivities. PMID:23361426

  10. Comparative measurements of plant radioactivity in the Agrobotanical Garden and experimental fields

    Directory of Open Access Journals (Sweden)

    Attila T. SZABO

    1986-08-01

    Full Text Available In order to demonstrate the usefulness of the Garden's Catalogue in unforeseen situations, the radioactivity of some plant species cultivated on different plots of the Agrobotanical Garden has been measured in May 1986. Comparative measurements have been carried out on species harvested from the experimental fields Sapca-Verde (Cluj-Napoca and from a collection trip in Tulcea county (Tulcea, Babadag, too. A monocanal energy spectrometer NK-350 (Gamma has been used for measurements; impulses per minute have been registered and plant radioactivity expressed in Becquerel (Bq units has been calculated. The highest values have been measured in the Agrobotanical Garden (alt. s.m. 475 m, incl. about 200 , exp. NE. Small-leaved low stature plants of Cyperaceae and Poaceae family have been much more radioactive than large-leaved Brassicaceae. In 28th May 1986 plants were generally more radioactive at basis as on top; older stems were 4-6 times more radioactive than top leaves or regrowth after harvest. Washing in running water (100 gr fresh weight in 50 l water for 5 minutes reduced the radioactivity levels measured in different species with about 30%.

  11. Development and application of a detector for absolute measurement of neutron fluence rate in MeV region

    International Nuclear Information System (INIS)

    The development and performance of the DTS (Dual Thin Scintillator) for the absolute measurement of the neutron fluence rate between 1 and 15 MeV is decribed. The DTS detector consists of a pair of organic scintillators in a dual configuration, where the incident produces a proton-recoil which is detected in a 2? geometry therefore avoiding the effect of the escape of protons. Thin scintillators are used resulting in small multiple scattering corrections. The theoretical caluclations of detector efficiency and proton-recoil spectrum were performed by means of a Monte Carlos code - CARLO DTS. The calculated efficiency was compared to the experimental one at two neutron energies namely 2.446 MeV and 14.04 MeV applying the Time Correlated Associated Particle technique. The theoretical and experimental efficiencies agreed within the experimental uncertainties of 1.44% and 0.77%, respectively. The performance of the DTS has been verified in an absolute 235U(n,f) cross section measurement between 1 and 6 MeV neutron energy. The cross section results were compared to those obtained replacing the DTS detector by the NBS (National Bureau of Standards, USA) Black Neutron Detector. The agreement was excellent in the overlapping energy interval of the two experiments (between 1 and 3 MeV), within the estimated uncertainly in the range of 1,0 to 1,7%. The agreement with the most recent evaluation from the ENDF/B-VI was excellent in almost all the energy range between 1 and 6 MeV. The 235U(n,f) cross section, average over the 252Cf fission neutron spectrum has been evaluated. The result including the cross section values of the present work was 1220 mb, in excellent agreement with the average value among the most recent measurements, 1227 +- 12 mb, and with the value 1213 mb, using the ENDF/B-VI data. (author)

  12. Absolute and ratio measurements of the polarizability of Na, K, and Rb with an atom interferometer

    Science.gov (United States)

    Holmgren, William F.; Revelle, Melissa C.; Lonij, Vincent P. A.; Cronin, Alexander D.

    2010-05-01

    We measured the ground-state electric-dipole polarizability of sodium, potassium, and rubidium using a Mach-Zehnder atom interferometer with an electric-field gradient. We find ?Na=24.11(2)stat(18)sys×10-24cm3, ?K=43.06(14)(33), and ?Rb=47.24(12)(42). Since these measurements were all performed in the same apparatus and subject to the same systematic errors, we can present polarizability ratios with 0.3% uncertainty. We find ?Rb/?Na=1.959(5), ?K/?Na=1.786(6), and ?Rb/?K=1.097(5). We combine our ratio measurements with the higher-precision measurement of sodium polarizability by Ekstrom [Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.51.3883 51, 3883 (1995)] to find ?K=43.06(21) and ?Rb=47.24(21).

  13. Absolute and ratio measurements of the polarizability of Na, K, and Rb with an atom interferometer

    International Nuclear Information System (INIS)

    We measured the ground-state electric-dipole polarizability of sodium, potassium, and rubidium using a Mach-Zehnder atom interferometer with an electric-field gradient. We find ?Na=24.11(2)stat(18)sysx10-24cm3, ?K=43.06(14)(33), and ?Rb=47.24(12)(42). Since these measurements were all performed in the same apparatus and subject to the same systematic errors, we can present polarizability ratios with 0.3% uncertainty. We find ?Rb/?Na=1.959(5), ?K/?Na=1.786(6), and ?Rb/?K=1.097(5). We combine our ratio measurements with the higher-precision measurement of sodium polarizability by Ekstrom et al. [Phys. Rev. A 51, 3883 (1995)] to find ?K=43.06(21) and ?Rb=47.24(21).

  14. Absolute and ratio measurements of the polarizability of Na, K, and Rb with an atom interferometer

    CERN Document Server

    Holmgren, William F; Lonij, Vincent P A; Cronin, Alexander D

    2010-01-01

    We measured the ground state electric dipole polarizability of sodium, potassium, and rubidium using a Mach-Zehnder atom interferometer with an electric field gradient. We find alpha_Na=24.11(2)_stat(18)_sys x 10^-24 cm^3, alpha_K=43.06(14)(33), and alpha_Rb=47.24(12)(42). Since these measurements were all performed in the same apparatus and subject to the same systematic errors we can present polarizability ratios with 0.3% precision. We find alpha_Rb/alpha_Na=1.959(5), alpha_K/alpha_Na=1.786(6), and alpha_Rb/alpha_K=1.097(5). We combine our ratio measurements with the higher precision measurement of sodium polarizability by Ekstrom et al. [Phys. Rev. A 51, 3883 (1995)] to find alpha_K=43.06(21) and alpha_Rb=47.24(21).

  15. Results and significance intercomparisons in the process of preparing radioactive certified reference materials

    International Nuclear Information System (INIS)

    To determine the activity (radioactive concentration) of radioactive certified reference materials (CRM) the National Office of Measures (OMH) applies absolute measuring methods. In order to check and reduce systematic uncertainties of measuring methods OMH currently participates in bilateral and multilateral intercomparisons. The paper reports on the results and experiences obtained during the latest intercomparisons (125I, 134Cs). (author)

  16. Absolute Measurement of the Reflectivity and the Point Spread Function of the MAGIC Telescopes

    Science.gov (United States)

    Kellermann, H.; Mirzoyan, R.; Schultz, C.; Hose, J.; Teshima, M.; Garczarczyk, M.

    2012-08-01

    In the past twenty years the ground-based Imaging Atmospheric Cherenkov Telescope (IACT) technique has revolutionized the understanding of cosmic rays. Over 120 sources of cosmic rays of both galactic and extragalactic origin have been observed in the very high energy regime of 50 GeV to 100 TeV. One key parameter of these measurements is the gamma ray flux, which is derived from the detection of gamma. ray induced Cherenkov light in the earth's atmosphere. The ratio between the total Cherenkov light hitting the primary IACT mirror and the projection on its camera has a direct impact on the precision of the flux measured. We have further improved an existing method for measuring in situ the reflectivity of the mirror of a telescope. The method is based on the simultaneous measurement of the brightness of both, a selected star directly and its image in the focal plane of the telescope. We applied this method to both 17 m diameter MAGIC IACTs operating on the Canary Island of La Palma. In this report we want to present the details of this method as well as results of the reflectivity measurements.

  17. Methods and instruments for absolute measurements of specific activity of nuclides

    International Nuclear Information System (INIS)

    The paper gives a description of some methods and instruments for measuring specific activity of nuclides. An installation with 4?-proportional counter is used for measurement of ?- and ?-radiations. For application in a coincidence circuit, the installation is supplied by blocks of detectors having crystalls of NaI. Dead-time of the channel with proportional counter equals to 4 mcs, resolution time of the coincidence circuit is variable from 0.4 to 2 mcs. To measure activity of nuclides with electron-capture decay, installation with 4? counter working under pre assure up to 2 MPa is used. Also, a method is given of determina tion of corrections in measurement by proportional counters. Corrections for self-absorption of ?- and?-particles a nd conversion electrons are determined by calculation. Self-absorption in the sources with radionuclides dacayed by electron capture is determined experimentally by means of ''weightless'' source which is prepared by the electrocalillar method. To check correctness of this approach, measurements of activity of 54Mn has been done by the coincidence method. Deviation of the results was more than 0.3%

  18. Absolute Thickness Measurements on Coatings Without Prior Knowledge of Material Properties Using Terahertz Energy

    Science.gov (United States)

    Roth, Don J.; Cosgriff, Laura M.; Harder, Bryan; Zhu, Dongming; Martin, Richard E.

    2013-01-01

    This study investigates the applicability of a novel noncontact single-sided terahertz electromagnetic measurement method for measuring thickness in dielectric coating systems having either dielectric or conductive substrate materials. The method does not require knowledge of the velocity of terahertz waves in the coating material. The dielectric coatings ranged from approximately 300 to 1400 m in thickness. First, the terahertz method was validated on a bulk dielectric sample to determine its ability to precisely measure thickness and density variation. Then, the method was studied on simulated coating systems. One simulated coating consisted of layered thin paper samples of varying thicknesses on a ceramic substrate. Another simulated coating system consisted of adhesive-backed Teflon adhered to conducting and dielectric substrates. Alumina samples that were coated with a ceramic adhesive layer were also investigated. Finally, the method was studied for thickness measurement of actual thermal barrier coatings (TBC) on ceramic substrates. The unique aspects and limitations of this method for thickness measurements are discussed.

  19. Absolute and ratio measurements of the polarizability of Na, K, and Rb with an atom interferometer

    OpenAIRE

    Holmgren, William F.; Revelle, Melissa C.; Lonij, Vincent P. A.; Cronin, Alexander D.

    2010-01-01

    We measured the ground state electric dipole polarizability of sodium, potassium, and rubidium using a Mach-Zehnder atom interferometer with an electric field gradient. We find alpha_Na=24.11(2)_stat(18)_sys x 10^-24 cm^3, alpha_K=43.06(14)(33), and alpha_Rb=47.24(12)(42). Since these measurements were all performed in the same apparatus and subject to the same systematic errors we can present polarizability ratios with 0.3% precision. We find alpha_Rb/alpha_Na=1.959(5), alp...

  20. Measurements of the absolute photoionization cross section of Fe+ ions from 15.8 to 180 eV

    International Nuclear Information System (INIS)

    The absolute single-and double-photoionization cross sections of singly charged Fe ions have been measured from 15.8 to 180 eV using the merged-beam technique. The data yield information about the photoionization continua and the resonance structures resulting from excitation of the outer 3d and 4s electrons as well as the inner 3p and 3s electrons. The vast majority of the Fe+ target ions were present in the ground-state configuration, 3d64s, and term,6D. The experimental data have been compared with several calculations, for example R-matrix calculations from the Opacity Project and data obtained using the central-field approximations. The experimental data are available at http://www.iop.orgww.ifa.au.dk/amo/atomphys/atomphys.htm. (author)

  1. Experimental ship fire measurements with simulated radioactive cargo

    International Nuclear Information System (INIS)

    Results from a series of eight test fires ranging in size from 2.2 to 18.8 MW conducted aboard the Coast Guard fire test ship Mayo Lykes at Mobile, Alabama are presented and discussed. Tests aboard the break-bulk type cargo ship consisted of heptane spray fires simulating engine room and galley fires, wood crib fires simulating cargo hold fires, and pool fires staged for comparison to land-based regulatory fire results. Primary instrumentation for the tests consisted of two pipe calorimeters that simulated a typical package shape for radioactive materials packages. (authors)

  2. Experimental ship fire measurements with simulated radioactive cargo

    International Nuclear Information System (INIS)

    Results from a series of eight test fires ranging in size from 2.2 to 18.8 MW conducted aboard the Coast Guard fire test ship Mayo Lykes at Mobile, Alabama are presented and discussed. Tests aboard the break bulk type cargo ship consisted of heptane spray fires simulating engine room and galley fires, wood crib fires simulating cargo hold fires, and pool fires staged for comparison to land based regulatory fire results. Primary instrumentation for the tests consisted of two pipe calorimeters that simulated a typical package shape for radioactive materials packages

  3. Measurements of radioactive and xenobiotic substances in the biological environment in the Netherlands 1986

    International Nuclear Information System (INIS)

    A brief survey of the results of detailed radioactivity measurements performed in the Netherlands during the period immediately after the Chernobylsk accident, and the risk analyses made on the basis of these results, are presented. The increase of the airborne radioactivity and the activity concentrations in surface water during the first week of May 1986 is demonstrated graphically. The radiation dose in 1986 due to artificial radioactivity has been calculated to be about 60 ?Sv for adults, 70 ?Sv for ten-year-old children and 110 ?Sv for one-year-old children. 54 figs.; 32 tabs

  4. Measurements of Natural Radioactivity in the Salt Cavern of the Polkowice - Sieroszowice Copper Mine

    International Nuclear Information System (INIS)

    Due to their low radioactivity background, underground physics laboratories offer a unique possibility for investigating extremely rare phenomena like proton decay, dark matter signals or neutrino physics/astrophysics related issues. The knowledge of the natural radioactivity background is essential for the success of an underground physics experiment. The following measurements of the natural radioactivity background, in the foreseen location of an underground physics laboratory in the salt layer, in the Polkowice-Sieroszowice copper mine are presented: concentration of natural radio-isotopes from in situ obtained gamma-ray spectra and from alpha spectroscopy of rock samples, radon concentration in the air and the dose determination. (author)

  5. ISRA, the Swiss information system for radioactive wastes as part of quality assurance measures

    International Nuclear Information System (INIS)

    In the management of radioactive operating waste, a complete documentation must be kept of the required quality assurance measures which ensure that the specified requirements are adhered to. Because of the quantity of data and the information requirements of the authorities involved, a Swiss information system for radioactive waste (ISRA) was set up as an EDP documentation system which takes the following tasks into account: - characterisation of the waste binding types, - creation of the individual binding documentation, -bookkeeping and reporting, - storage management and transport. Thanks to ISRA, the documentation in the administration of radioactive waste can be dealt with simply, safely, and economically. (author) 2 figs., 1 tab., 4 refs

  6. Measurement of radioactivity in the atmosphere and pollution nearby an atomic centre

    International Nuclear Information System (INIS)

    The French Atomic Energy Commission (CEA) is particularly interested in studies on atmospheric radioactivity by reason of the necessity to control the atmosphere nearby nuclear plants as uranium mines, nuclear reactors and hot laboratories or radioactive materials treatment plants. Thus, the CEA developed different apparatus to control and monitor the atmosphere nearby its sites. These air monitors are essentially of two types: the first one, called 'Babar', monitors smokes, fogs and dusts, the second type is an ionization chamber and measures the concentration of radioactive gas in the air. The functioning and sensitivity of these two systems are discussed. (M.P.)

  7. Absolute pulse energy measurements of soft x-rays at the Linac Coherent Light Source.

    Czech Academy of Sciences Publication Activity Database

    Tiedtke, K.; Sorokin, A. A.; Jastrow, U.; Jurani?, P.; Kreis, S.; Gerken, N.; Richter, M.; Arp, U.; Feng, Y.; Nordlund, D.; Soufli, R.; Fernández-Perea, M.; Juha, Libor; Heimann, P.; Nagler, B.; Lee, H.J.; Mack, S.; Cammarata, M.; Krupin, O.; Messerschmidt, M.; Holmes, M.; Rowen, M.; Schlotter, W.; Moeller, S.; Turner, J.J.

    2014-01-01

    Ro?. 22, ?. 18 (2014), s. 21214-21226. ISSN 1094-4087 R&D Projects: GA MŠk(CZ) LG13029 Institutional support: RVO:68378271 Keywords : soft x-ray * free electron laser * LCLS * instrumentation * measurement * metrology Subject RIV: BH - Optics, Masers, Lasers Impact factor: 3.488, year: 2014

  8. Surveillance of radioactivity by the German Meteorological Service. Automatic nuclide specific measurements

    International Nuclear Information System (INIS)

    The DWD (Deutscher Wetterdienst, German Meteorological Service) is charged by law with the surveillance of radioactivity in the atmosphere. In the frame of the ''Integrated Measuring and Information System for the Surveillance of Radioactivity in the Environment'' (IMIS) the measuring tasks of DWD are well described. Since 2009 it was aimed for the automatic measurement of aerosol-bound radionuclides, gaseous Iodine-131 and deposited radionuclides at the 48 measuring sites of DWD. To guarantee the continuous operation of germanium detectors it was necessary to install electrically cooled systems instead of systems cooled by liquid nitrogen. The technical details and the experiences are described.

  9. Portable scintillation gamma-spectrometer for field measurement of radioactivity in extensive objects

    International Nuclear Information System (INIS)

    The portable scintillated gamma-spectrometer for field measurement of radioactivity in the volume objects was designed. The crystal CdWO4 that has weak dependence of light yield from temperature in combination with PMT was applied as the gamma-rays detector. The design of the device provides the possibility for measuring radioactivity of the extensive objects in 4?-geometry without background measurements. In this case the value of the efficiency needed for specific activity calculation in close approximation depends only from crystal geometry and density of measuring object and may be set as the device parameter without efficiency calibration procedure during the operation. The spectrometer does not have an auxiliary radio-active source and connecting cables in the composition. The smartphone operated under Windows Mobile is used as the control module. Bluetooth connection provides data exchange between smartphone and measurement head.

  10. Measures to ensure safety of radioactive materials in India

    International Nuclear Information System (INIS)

    In India, the use of ionizing radiation sources in industry, medicine, agriculture and research registered a significant increase during recent years. The basis of legislative control of the use of radiation in India is the Atomic Energy Act from 1962, which empowers the central Government to provide control over radioactive substances. Exercising these powers, the central Government has promulgated several radiation safety rules, which specify the requirements of licensing, the duties and responsibilities of radiation safety officers, powers of inspection, etc. Later in 1983, by the Act, the Atomic Energy Regulatory Board (AERB) was constituted by the central Government to exercise regulatory and safety functions. The report describes the existing system of regulatory control of radiation sources in India and in particular, refers to the regulatory documents prepared by the AERB, the type approval of radiation equipment, the regulatory consent for every person handling radioactive sources, and the inspection activities and enforcement of regulatory actions. The report also explains how management of disused sources is carried out in India, including the handling of accidents and emergency activities. (author)

  11. Measurement of the absolute branching fraction of Ds+ --> tau+ nutau decay.

    Science.gov (United States)

    Ecklund, K M; Love, W; Savinov, V; Lopez, A; Mendez, H; Ramirez, J; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Rademacker, J; Asner, D M; Edwards, K W; Naik, P; Reed, J; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Libby, J; Powell, A; Wilkinson, G

    2008-04-25

    Using a sample of tagged D(s)(+) decays collected near the D(s)(*+/-)D(s)(-/+) peak production energy in e(+)e(-) collisions with the CLEO-c detector, we study the leptonic decay D(s)(+)-->tau(+)nu(tau) via the decay channel tau(+)-->e(+)nu(e)nu(tau). We measure B(D(s)(+)-->tau(+)nu(tau))=(6.17+/-0.71+/-0.34)%, where the first error is statistical and the second systematic. Combining this result with our measurements of D(s)(+)-->mu(+)nu(mu) and D(s)(+)-->tau(+)nu(tau) (via tau(+)-->pi(+)nu(tau)), we determine f(D(s))=(274+/-10+/-5) MeV. PMID:18518183

  12. Flux depression and the absolute measurement of the thermal neutron flux density

    International Nuclear Information System (INIS)

    The thermal neutron flux depression in a diffusing medium by an absorbing foil has been treated in numerous papers. The results are re-examined in an attempt to find a uniform and physically meaningful representation of the 'activation correction'. This quantity can be split up into a combination of probabilities. Thus, it is possible to determine the activation correction for any moderator and foil material. Measurements confirm the utility of the concepts introduced. (orig.)

  13. Measurement of the Absolute Proton and Helium Flux at the Top of the Atmosphere using IMAX

    DEFF Research Database (Denmark)

    Menn, W.; Hof, M.; Reimer, O.; Simon, M.; Barbier, L.M.; Christian, E.R.; Krombel, K.E.; Mitchell, J.W.; Ormes, J.F.; Streitmatter, R.E.; Davis, A.J.; Labrador, A.W.; Mewaldt, R.A.; Schindler, S.M.; Golden, R.L.; Stochaj, S.J.; Webber, W.R.; Rasmussen, Ib Lundgaard

    1996-01-01

    The balloon-borne experiment IMAX launched from Lynn Lake, Canada in 1992 has been used to measure the cosmic ray proton and helium spectra from 0.2 GV to approximately 100 GV. The IMAX apparatus was designed to search for antiprotons and light isotopes using a superconducting magnet spectrometer with ancillary scintillators, time-of-flight, and aerogel cherenkov detectors. High resolution drift chambers and MWPCs were used as the tracking devices. Using redundant detectors, an extensive examina...

  14. Flux depression and the absolute measurement of the thermal neutron flux density

    International Nuclear Information System (INIS)

    The thermal neutron flux depression in a diffusing medium by an absorbing foil has been treated in numerous papers. The results are re-examined in an attempt to find a uniform and physically meaningful representation of the 'activation correction'. This quantity can be split up into a combination of probabilities. Thus, it is possible to determine the activation correction for any moderator and foil material. Measurements confirm the utility of the concepts introduced

  15. Absolute frequency measurement of the magnesium intercombination transition $^1S_0 \\to ^3P_1$

    CERN Document Server

    Friebe, Jan; Riedmann, Matthias; Moldenhauer, Karsten; Mehlstäubler, Tanja; Rehbein, Nils; Lisdat, Christian; Rasel, Ernst M; Ertmer, Wolfgang; Schnatz, Harald; Lipphardt, Burghard; Grosche, Gesine

    2007-01-01

    We report on a frequency measurement of the $(3s^2)^1S_0\\to(3s3p)^3P_1$ clock transition of $^{24}$Mg on a thermal atomic beam. The intercombination transition has been referenced to a portable primary Cs frequency standard with the help of a femtosecond fiber laser frequency comb. The achieved uncertainty is $2.5\\times10^{-12}$ which corresponds to an increase in accuracy of six orders of magnitude compared to previous results. The measured frequency value permits the calculation of several other optical transitions from $^1S_0$ to the $^3P_J$-level system for $^{24}$Mg, $^{25}$Mg and $^{26}$Mg. We describe in detail the components of our optical frequency standard like the stabilized spectroscopy laser, the atomic beam apparatus used for Ramsey-Bord\\'e interferometry and the frequency comb generator and discuss the uncertainty contributions to our measurement including the first and second order Doppler effect. An upper limit of $3\\times10^{-13}$ in one second for the short term instability of our optical f...

  16. Measures Against-Illicit Trafficking of Nuclear Materials and Other Radioactive Sources

    International Nuclear Information System (INIS)

    Since the early nineties, illicit trafficking (IT) of nuclear materials and radioactive sources appeared as a new trend which raised the concern of the international community due to the grave consequences that would merge if these materials or radioactive sources fell into the hands of terrorist groups. However, by the end of the last century illicit trafficking of nuclear materials and radioactive sources lost its considerable salience, in spite of seizure of considerable amounts of 2'3'5U (76% enrichment) in Bulgaria (May 1999) and also 235U (30% enrichment) in Georgia (April 2000). Nevertheless, IT should be always considered as a continued and viable threat to the international community. Awareness of the problem should be developed and maintained among concerned circles as the first step towards combating illicit trafficking of nuclear materials and radioactive sources. Illicit trafficking of nuclear and radioactive materials needs serious consideration and proper attention by the governmental law enforcement authorities. Measures to combat with IT of nuclear material or radioactive sources should be effective in recovery, of stolen, removed or lost nuclear materials or radioactive sources due to the failure of the physical protection system or the State System Accounting and Control (SSAC) system which are normally applied for protecting these materials against illegal actions. Measures such as use of modern and efficient radiation monitoring equipment at the borders inspection points, is an important step in preventing the illicit trafficking of nuclear and radioactive materials across the borders. Also providing radiological training to specific personnel and workers in this field will minimize the consequences of a radiological attack in case of its occurrence. There is a real need to start to enter into cooperative agreements to strengthen borders security under the umbrella of IAEA to faster as an international cooperation in the illicit trafficking of nuclear material and radioactive sources

  17. Systematic Uncertainties in the Spectroscopic Measurements of Neutron-Star Masses and Radii from Thermonuclear X-ray Bursts. III. Absolute Flux Calibration

    OpenAIRE

    Guver, Tolga; Ozel, Feryal; Marshall, Herman; Psaltis, Dimitrios; Guainazzi, Matteo; Diaz-Trigo, Maria

    2015-01-01

    Many techniques for measuring neutron star radii rely on absolute flux measurements in the X-rays. As a result, one of the fundamental uncertainties in these spectroscopic measurements arises from the absolute flux calibrations of the detectors being used. Using the stable X-ray burster, GS 1826-238, and its simultaneous observations by Chandra HETG/ACIS-S and RXTE/PCA as well as by XMM-Newton EPIC-pn and RXTE/PCA, we quantify the degree of uncertainty in the flux calibratio...

  18. DeGeN - Measurement vehicle for radioactive and nuclear material: Poster presented at 4th European IRPA Congress 2014, June 23rd to June 27th 2014, Geneva, Switzerland

    OpenAIRE

    Köble, Theo; Berky, Wolfram; Chmel, Sebastian; Friedrich, Hermann; Risse, Monika; Rosenstock, Wolfgang; Schumann, Olaf

    2014-01-01

    The measurement system DeGeN comprises gamma and neutron detectors with high sensitivity suitable for detecting radioactive and nuclear (RN) material. Because of the high sensitivity, even minor changes of the natural background radiation can be registered which is tremendously important for the discrimination between the presence of actual RN material and mere modifications of the natural background. Knowledge about such a discrimination is absolutely necessary in order to be able to evaluat...

  19. Absolute Equation of State Measurements on Shocked Liquid Deuterium up to 200GPa (2Mbar)

    International Nuclear Information System (INIS)

    We present results of the first measurements of density, shock speed, and particle speed in liquid deuterium compressed by laser-generated shock waves to pressures from 25 to 210Gpa (0.25 to 2.1Mbar). The data show a significant increase in D2 compressibility above 50Gpa compared to a widely used equation of state model. The data strongly suggest a thermal molecular dissociation transition of the diatomic fluid into a monatomic phase. copyright 1997 The American Physical Society

  20. Absolute brightness measurement of X-ray emission from laser-produced plasma using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Thermoluminescent dosemeters of LiF:Mg,Ti, LiF:Mg,Cu,P and CaF2:Dy were used as secondary standards in calibration measurements of X-ray emission from a laser-produced aluminium plasma. Relative sensitivities of the thermoluminescent dosemeters were found to be independent of dose rate over a wide dose rate region. The photon detection efficiency of thermoluminescent dosemeters is compared to that of semiconductor Si photodiodes. The thermoluminescent dosemeters are presented as a powerful tool for testing of capability of a semiconductor photodiode detector of X-ray pulse energy emitted from the laser-produced plasma. (orig.)

  1. Absolute molecular flux and angular distribution measurements to characterize DNA/RNA vapor jets

    Energy Technology Data Exchange (ETDEWEB)

    Tabet, J. [Universite de Lyon, F-69003, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS/IN2P3, UMR5822, Institut de Physique Nucleaire de Lyon, 4 rue Enrico Fermi, Villeurbanne (France); Eden, S. [Universite de Lyon, F-69003, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS/IN2P3, UMR5822, Institut de Physique Nucleaire de Lyon, 4 rue Enrico Fermi, Villeurbanne (France); Department of Physics and Astronomy, Open University (OU), Walton Hall, Milton Keynes, MK7 6AA (United Kingdom); Feil, S.; Abdoul-Carime, H. [Universite de Lyon, F-69003, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS/IN2P3, UMR5822, Institut de Physique Nucleaire de Lyon, 4 rue Enrico Fermi, Villeurbanne (France); Farizon, B., E-mail: bfarizon@ipnl.in2p3.f [Universite de Lyon, F-69003, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS/IN2P3, UMR5822, Institut de Physique Nucleaire de Lyon, 4 rue Enrico Fermi, Villeurbanne (France); Farizon, M. [Universite de Lyon, F-69003, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS/IN2P3, UMR5822, Institut de Physique Nucleaire de Lyon, 4 rue Enrico Fermi, Villeurbanne (France); Ouaskit, S. [Laboratoire de physique de la matiere condensee, Unite associee au CNRST(URAC 10), Faculte des sciences Ben M' sik, B.P.7955, Casablanca (Morocco); Maerk, T.D. [Institut fuer Ionenphysik und Angewandte Physik, Leopold Franzens Universitaet, Technikerstrasse 25, A-6020 Innsbruck (Austria)

    2010-08-01

    Vapor jets of DNA and RNA bases (adenine, cytosine, thymine, and uracil) from an oven with a capillary exit have been studied in the intermediate regime between molecular and viscous flow corresponding to Knudsen numbers in the range 0.1 < K{sub n} < 10. The temperature control method ensured stationary flow. Assuming the Knudsen hypothesis, the pressure of sublimated molecules in the oven was determined as a function of temperature and the transmission probability of the capillary (Clausing factor). Thus it was possible to relate the oven temperature and pressure to the total flux through the capillary, determined by measuring the total mass of DNA/RNA base molecules condensed on a cold surface intersecting the jet. The angular distribution of molecules in the jet has been also studied experimentally using an optical interference method. The measured profiles are in good agreement with Troitskii's [Sov. Phys. JETP 7 (1962) 353] analytical law for (cos {theta}){sup 3/2} angular dependence in the intermediate regime with error functions associated with the mean free path between intermolecular collisions.

  2. Measurement of absolute branching fractions of inclusive semileptonic decays of charm and charmed-strange mesons

    International Nuclear Information System (INIS)

    We have measured the inclusive semileptonic branching fractions of D0, D+, and Ds+ mesons. For these measurements, we have used the full CLEO-c open-charm data samples, 818 pb-1 at ECM=3.774 GeV, giving D0D0 and D+D- events, and 602 pb-1 at ECM=4.170 GeV, giving Ds*±Ds± events. We obtain B(D0?Xe+?e)=(6.46±0.09±0.11)%, B(D+?Xe+?e)=(16.13±0.10±0.29)%, and B(Ds+?Xe+?e)=(6.52±0.39±0.15)%, where the first uncertainties are statistical and the second are systematic. From these and lifetimes obtained elsewhere, we obtain the ratios of semileptonic decay widths ?(D+?Xe+?e)/?(D0?Xe+?e)=0.985±0.015±0.024 and ?(Ds+?Xe+?e)/?(D0?Xe+?e)=0.828±0.051±0.025. The ratio of D+ and D0 is consistent with the isospin symmetry prediction of unity, and the ratio of Ds+ and D0 differs from unity, as expected.

  3. Absolute activity measurement and gamma-ray emission probability for decay of I-126

    CERN Document Server

    Fonseca, K A

    1997-01-01

    The accurate knowledge of the gamma-ray emission probability per decay of radionuclides is important in several applications. In the case of sup 1 sup 2 sup 6 I, its importance lies mainly in fast neutron dosimetry as well as in the production of sup 1 sup 2 sup 5 I where sup 1 sup 2 sup 6 I appears as an impurity. In the present work the gamma-ray emission probabilities per decay for the 388 and 666-KeV transitions of sup 1 sup 2 sup 6 I have been measured. This radionuclide was obtained by means of the sup 1 sup 2 sup 7 I(n, 2n) sup 1 sup 2 sup 6 I reaction in a fast neutron flux at the IPEN 2 MW research reactor. The methodology for the primary standardization of sup 1 sup 2 sup 6 I is described. For this purpose, two different coincidence systems were used due to the complex decay scheme of this radionuclide. The beta branch measurement was carried out in a 4 pi(PC)beta-gamma coincidence system consisting of a proportional counter, coupled to a pair of 3'x3' Na I (Tl) crystal. The electron capture branch ...

  4. Radioactivity measurements in air over Europe after the Chernobyl accident

    Science.gov (United States)

    Raes, Frank; Graziani, Giovanni; Stanners, David; Girardi, Franco

    A comprehensive European data set of radioactivity in air caused by the accident at the Chernobyl nuclear power plant is presented. For the first 2 weeks after the beginning of the release, levels of particulate I-131, Cs-134 and Cs-137 (85 locations) and of total I-131 (10 locations) are given. All data are stored in a computerized data base. For the first time the passage of the Chernobyl cloud over Europe is mapped after re-averaging the time histories in each location to produce coherent daily concentrations. Cs-134/Cs-137 ratios were analyzed: the 'European' average ratio calculated from 1239 samples is 0.55, with a standard deviation of 0.25.

  5. An electrostatic radon detector designed for water radioactivity measurements

    CERN Document Server

    Wang Jian Xiong; Simpson, J J

    1999-01-01

    The Sudbury Neutrino Observatory contains 1000 t of ultra-pure heavy water and 7000 t of very pure light water. In order to achieve the goal of determining accurately the total number of neutrinos emitted by the sun regardless of type, the radioactivity in the water must be maintained with a radiopurity of less than 10 sup - sup 1 sup 4 g/g of sup 2 sup 3 sup 2 Th and sup 2 sup 3 sup 8 U in secular equilibrium with their daughters. This paper describes the design and application of an electrostatic radon detector which determines the amount of radon emanating from a column containing MnO sub 2 used to extract radium from the water. This electrostatic radon detector has a total efficiency of 35% for detecting sup 2 sup 2 sup 2 Rn and 22% for sup 2 sup 2 sup 0 Rn.

  6. Simulation of real-time large-scale absolute distance measurement with a pair of femtosecond frequency comb lasers

    Science.gov (United States)

    Li, Yang; Zhou, Qian; Ni, Kai; Wu, Guanhao; Qiao, Xiaorui

    2012-11-01

    Absolute distance measurement is essential in large-scale equipment manufacturing and scientific projects. Nowadays, sophisticated equipment manufacture demands for high-precision ranging with a high speed. Several raging methods utilizing the wide spectral range and stable frequency intervals of femtosecond frequency comb laser can achieve a high precision, but most of such systems suffer from relative low speed. Fortunately, the ranging method based on a pair of femtosecond frequency comb lasers can potentially resolve such problem. Combining time-of-flight and interferometry method, the measurement can accomplish rapid raging in a measurement period of 0.2ms, and achieve higher precision by interferometry after averaging of many periods. We performed a simulation of this method in Matlab/Simulink. The precision can achieve ~10nm in ideal simulation environment. By error analysis we estimated the data processing system, and gave the appropriate parameters of detector and A/D sampling. It comes to a conclusion that detector with relative long response time of ~7nm or about can be adopted, and fast Fourier transformation (FFT) of 16384 points contributes to higher precision. With such parameters, it is possible to realize real-time raging performed on field-programmable gate array (FPGA) with high precision.

  7. Absolute values of transport mean free path of light in non-absorbing media using transmission and reflectance measurements

    Scientific Electronic Library Online (English)

    J, Galvan-Miyoshi; R, Castillo.

    2008-06-01

    Full Text Available En este trabajo se deriva una relación entre el camino libre medio de trasporte de la luz y la transmitancia y la reflectancia de un medio turbio no absorbente. Esto nos permitió desarrollar un procedimiento experimental para obtener valores absolutos de los caminos libres medio de transporte de la [...] luz con solo medir, en una esfera integradora, la trasnmitancia y la reflectancia en esta clase de sistemas. Hemos determinado cuán preciso es nuestro método comparando nuestras medidas de camino libre medio de transporte con cálculos efectuados para suspensiones coloidales utilizando la teoría de dispersión de Mie y con medidas hechas en suspensiones coloidales de microesferas utilizando espectroscopia de onda difusa. El acuerdo es excelente. Abstract in english We derived a relation between the transport mean free path of light, and transmittance and the reflectance in non-absorbing turbid media. This allowed us to develop an experimental procedure to obtain absolute values for the transport mean free path of light just by measuring in an integrating spher [...] e both the transmittance and the reflectance in this kind of system. We determined how accurate our method was by comparing our transport mean free path measurements with calculations made for colloidal suspensions of particles using Mie scattering theory and with measurements made in colloidal suspensions of polystyrene microspheres using diffusive wave spectroscopy. The agreement is excellent.

  8. The radioactivity measurement in the Loire catchment basin. Actors, networks, data inventory

    International Nuclear Information System (INIS)

    The objective of this report on the Loire watershed was to broaden at all the nuclear installations of the watershed the method of synthesis made for Saint-Laurent-des-Eaux nuclear power plant, by resting on the whole of actors doing the radioactivity measurements in environment. This report shows that these actors are numerous. The measurement plans implemented have for objective to establish the radiological situation of environment, near or not the nuclear facilities, to detect the abnormal increase of radioactivity, to evaluate the exposure of populations to the ambient radioactivity, or to check the conformity of practices (nuclear activities) and products. This assessment enlightens the lack of a real global strategy in the organisation of the radioactivity measurement at the level of the watershed. The inventory of available data for the Loire watershed allowed to show the diversity of measurements realised. The I.R.S.N. is face to a complex situation of data return in the frame of the implementation of an information system of the national network of radioactivity measurement in environment. (N.C.)

  9. Preventive measures for radioactive contamination in iron and steel used as construction materials

    International Nuclear Information System (INIS)

    At the end of July 1992, Atomic Energy Council (AEC) received tips-off from Taipei local residents, saying some buildings in Taipei had their rebar been contaminated by radioactive materials. Regarding causes and sources of those radioactively contaminated rebar, views from every aspects were pointing toward that scraps mixed with radioactive source smelting in the steel mill as the most possible reason. After investigating houses and constructors, AEC found that most contaminated buildings were constructed during the period of 1982 and 1984. For protection of public rights, AEC then actively undertook nation-wide survey of more than forty thousand buildings constructed between 1982 and 1984. Thermal Luminescent Dosimeters (TLD) and house by house surveying were major methods to investigate houses contamination. Finally, it was found that radiation contaminated houses are concentrated in Taipei City, Taipei County, Tauoyen County, Keelung County. According to data collected up to December 31, 1999, there were 180 cases, with a total of 1601 contaminated housing units. Based on information data of dose assessment, distribution of annual dose are as the following: higher than 15 mSv -143 housing units (9.21%), 5-15 mSv -117 housing units (7.53%), less than 5 mSv -1293 housing units (83.26%). Except actively conducting remodeling of contaminated houses and granting compensation to house owners, AEC has established following measures to prevent rebars from being radioactively contaminated. (1) Radiation detection training of iron and steel detectors (2) Strengthening controls over radioactive sources (3) Enforcing examination of radioactive levels for imported rebars (4) Requesting domestic steel companies establish radiation detection capability (5) Promoting installation of portal type radiation detectors for steel companies having smelting furnace (6) Enforcing no-radioactive contamination certificate system. The radiation detection training of iron and steel detectors began in middle January 1995, there were 10,395 people finished training in the end of December 1999. There have been 163 iron and steel companies certified by AEC as having radiation detection capability since AEC assisted them to set up such capability in 1993. There is only one mill which having melting furnace but has not installed portal type detector. As end of December 1999 iron and steel mills had discovered 20 cases of foreign and 33 cases of domestic radioactive sources and radioactive substances in scraps since abnormal radioactive scrap was first found in June 1994, and successfully prevented radioactive substances from going into furnace. Those measures ensure that the rebars used for construction are free from radioactive contamination and protects as well as the safety of living environment for the public. (author)

  10. Continuous measurement of gas flow using a hinged gate and a radioactive source

    International Nuclear Information System (INIS)

    The continuous measurement of volumetric flow of gas in turbulent and laminar condition is proposed using a small radioactive source mounted on a hinged gate. The use of radioactivity enables measurement of the gate-inclination to be made outside the pipe, thus establishing the pattern of a simple instrument. The use of penetrating radiation also results in an extension of the operating range since it allows application of a multi-gate system; an external detector then gives simultaneous measurement of the resultant inclination of several gates. Relationships between volume flow and detector current for single and multiplegate systems are given. (author)

  11. The development of automatic surface dose-rate measuring and recording system for radioactive waste drum

    International Nuclear Information System (INIS)

    The system which is performed the transportation and measurement of drum automatically to measure the surface dose-rate of radioactive waste drum and can inspect place of contaminated sources and precise dose-rate within a drum according to measuring many places equally at the same time has been developed. It is expected that the system be used to minimized radiation exposure of workers and manage the drum effectively according to established at the production facilities as well as the radioactive waste treatment facilities. (author). 7 refs., 9 tabs., 16 figs

  12. Second summarizing progress report of radioactivity measurements after the nuclear accident at Chernobyl

    International Nuclear Information System (INIS)

    This report contains continued measurements of the environmental impact in the Netherlands of the reactor accident at Chernobyl, April 26 1986. The monitoring was carried out on behalf of the Dutch government. Transport and precipitation of the radioactivity emitted in the USSR are considered. Measurements are presented of the radioactivity in the Dutch environment, in the food chain and in products. Radiation exposure of man is also discussed. This report covers the measuring results during the period May 13 - June 20 1986. (G.J.P.)

  13. Absolute measurement of cerebral optical coefficients, hemoglobin concentration and oxygen saturation in old and young adults with near-infrared spectroscopy

    Science.gov (United States)

    We present near-infrared spectroscopy measurement of absolute cerebral hemoglobin concentration and saturation in a large sample of 36 healthy elderly (mean age, 85 ± 6 years) and 19 young adults (mean age, 28 ± 4 years). Non-invasive measurements were obtained on the forehead using a commercially a...

  14. Calibration of a gamma spectrometer for natural radioactivity measurement. Experimental measurements and Monte Carlo modelling

    International Nuclear Information System (INIS)

    The thesis proceeded in the context of dating by thermoluminescence. This method requires laboratory measurements of the natural radioactivity. For that purpose, we have been using a germanium spectrometer. To refine the calibration of this one, we modelled it by using a Monte-Carlo computer code: Geant4. We developed a geometrical model which takes into account the presence of inactive zones and zones of poor charge-collection within the germanium crystal. The parameters of the model were adjusted by comparison with experimental results obtained with a source of 137Cs. It appeared that the form of the inactive zones is less simple than is presented in the specialized literature. This model was widened to the case of a more complex source, with cascade effect and angular correlations between photons: the 60Co. Lastly, applied to extended sources, it gave correct results and allowed us to validate the simulation of matrix effect. (author)

  15. Proficiency Tests for Environmental Radioactivity Measurement Organized by an Accredited Laboratory

    Science.gov (United States)

    Aubert, Cédric; Osmond, Mélanie

    2008-08-01

    For 40 years, STEME (Environmental Sample Processing and Metrology Department) organized international proficiency testing (PT) exercises formerly for WHO (World Health Organization) and EC (European Community) and currently for ASN (French Nuclear Safety Authority). Five PT exercises are organized each year for the measurement of radionuclides (alpha, beta and gamma) in different matrixes (water, soil, biological and air samples) at environmental levels. ASN can deliver a French ministerial agreement to participate on environmental radioactivity measurements French network for laboratories asking it [1]. Since 2006, November, STEME is the first French entity obtaining a COFRAC (French Committee of Accreditation) accreditation as "Interlaboratory Comparisons" for the organization of proficiency tests for environmental radioactivity measurement according to standard International Standard Organization (ISO) 17025 and guide ISO 43-1. STEME has in charge to find, as far as possible, real sample or to create, by radionuclide adding, an adapted sample. STEME realizes the sampling, the samples preparation and the dispatching. STEME is also accredited according to Standard 17025 for radioactivity measurements in environmental samples and determines homogeneity, stability and reference values. After the reception of participating laboratories results, STEME executes statistical treatments in order to verify the normal distribution, to eliminate outliers and to evaluate laboratories performance. Laboratories participate with several objectives, to obtain French agreement, to prove the quality of their analytical performance in regards to standard 17025 or to validate new methods or latest developments. For 2 years, in addition to usual PT exercises, new PT about alpha or beta measurement in air filters, radioactive iodine in carbon cartridges or measurement of environmental dosimeters are organized. These PT exercises help laboratories to improve radioactive measurements and to rectify old mistakes. The PT exercises organized by STEME are becoming essential for French and some European laboratories working in radioactive measurements. The STEME organization, in respect of accreditation references, is presented.

  16. Proficiency Tests for Environmental Radioactivity Measurement Organized by an Accredited Laboratory

    International Nuclear Information System (INIS)

    For 40 years, STEME (Environmental Sample Processing and Metrology Department) organized international proficiency testing (PT) exercises formerly for WHO (World Health Organization) and EC (European Community) and currently for ASN (French Nuclear Safety Authority). Five PT exercises are organized each year for the measurement of radionuclides (alpha, beta and gamma) in different matrixes (water, soil, biological and air samples) at environmental levels. ASN can deliver a French ministerial agreement to participate on environmental radioactivity measurements French network for laboratories asking it. Since 2006, November, STEME is the first French entity obtaining a COFRAC (French Committee of Accreditation) accreditation as 'Interlaboratory Comparisons' for the organization of proficiency tests for environmental radioactivity measurement according to standard International Standard Organization (ISO) 17025 and guide ISO 43-1. STEME has in charge to find, as far as possible, real sample or to create, by radionuclide adding, an adapted sample. STEME realizes the sampling, the samples preparation and the dispatching. STEME is also accredited according to Standard 17025 for radioactivity measurements in environmental samples and determines homogeneity, stability and reference values. After the reception of participating laboratories results, STEME executes statistical treatments in order to verify the normal distribution, to eliminate outliers and to evaluate laboratories performance.Laboratories participate with several objectives, to obtain French agreement, to prove the quality of their analytical performance in regards to standard 17025 or to validate new methods or latest developments. For 2 years, in addition to usual PT exercises, new PT about alpha or beta measurement in air filters, radioactive iodine in carbon cartridges or measurement of environmental dosimeters are organized. These PT exercises help laboratories to improve radioactive measurements and to rectify old mistakes. The PT exercises organized by STEME are becoming essential for French and some European laboratories working in radioactive measurements.The STEME organization, in respect of accreditation references, is presented

  17. Measuring absolute frequencies beyond the GPS limit via long-haul optical frequency dissemination

    CERN Document Server

    Clivati, C; Livi, L; Poggiali, F; de Cumis, M Siciliani; Mancini, M; Pagano, G; Frittelli, M; Mura, A; Costanzo, G A; Levi, F; Calonico, D; Fallani, L; Catani, J; Inguscio, M

    2015-01-01

    Global Positioning System (GPS) dissemination of frequency standards is ubiquitous at present, providing the most widespread time and frequency reference for the majority of industrial and research applications worldwide. On the other hand, the ultimate limits of the GPS presently curb further advances in high-precision, scientific and industrial applications relying on this dissemination scheme. Here, we demonstrate that these limits can be reliably overcome even in laboratories without a local atomic clock by replacing the GPS with a 642-km-long optical fiber link to a remote primary caesium frequency standard. Through this configuration we stably address the $^1$S$_0$---$^3$P$_0$ clock transition in an ultracold gas of $^{173}$Yb, with a precision that exceeds the possibilities of a GPS-based measurement, dismissing the need for a local clock infrastructure to perform high-precision tasks beyond GPS limit. We also report an improvement of two orders of magnitude in the accuracy on the transition frequency ...

  18. Validation of a Monte Carlo model for a GMX detector used for measurements of environmental radioactivity

    International Nuclear Information System (INIS)

    In an Environmental Radioactivity Laboratory, samples from several products are analyzed, in order to determine the amount of radioactive products they contain. A usual method is the gamma activity measurement of these samples, which typically requires the use of High Purity Germanium Detectors (HPGe). GMX (n-type) detectors can be found among this group of detectors. They have a high efficiency for low energy emissions. As any detector, it must be calibrated, in energy, efficiency and resolution (FWHM). To do this calibration, a gamma standard solution is used, whose composition and activity are certified by a reference laboratory. This source contains several radionuclides, providing a wide energy spectrum. The simulation of the detection process with MCNP5, a code based on the Monte Carlo method, is a useful tool in an Environmental Radioactivity Laboratory, since it can reproduce the experimental conditions of the essay, without manipulating radioactive sources, and consequently reducing radioactive wastes. On the other hand, the simulation of the detector calibration permits to analyze the influence of different variables on detector efficiency. In this paper, the simulation of the calibration of the GMX detector used in the Environmental Radioactivity Laboratory of the Polytechnic University of Valencia (UPV) is presented. Results obtained with this simulation are compared with laboratory measurements, in order to validate the model. (author)

  19. Effect of background radiation shielding on natural radioactivity distribution measurement with imaging plate

    International Nuclear Information System (INIS)

    Distribution images of natural radioactivity contained in various natural materials such as vegetable, animal meat and pottery work can be obtained with an imaging plate which has high sensitivity for nuclear radiations. For such very low levels of radioactivity, natural background radiations must be reduced using a shielding box. The lining, on the inside of the box, with low atomic number material such as acrylic resin is very effective in reducing electrons, ?-rays and low energy X- and ?-rays emitted from the inner surface of the shielding material. Some images of natural radioactivity distribution were obtained and the radioactivity, mainly 40K, contained in natural materials was measured by using an HPGe detector and also the imaging plate itself. (orig.)

  20. The Japan Power Demonstration Reactor decommissioning program. Decontamination and radioactivity measurement on building surfaces

    International Nuclear Information System (INIS)

    After dismantling the components in the facilities of Japan Power Demonstration Reactor (JPDR), decontamination on concrete surfaces and final survey of radioactivity have been started as the last step in the JPDR dismantling activities. At the first step for the decontamination on concrete surfaces and the final survey of radioactivity is as follows; The contamination on the concrete surfaces in the JPDR facility was characterized on the basis of radioactivity measurements of samples taken from the buildings. The contamination in the JPDR facility was categorized into two groups: fixed or removable; deep penetrative contamination was not found in the JPDR facility. The distribution map of the contamination was made based on the characterization. Decontamination activities were planned according to the distribution map of the contamination. The all buildings will be demolished and the site will be landscaped after finishing the final survey of radioactivity by March 1996. (author)

  1. Absolute beginners

    OpenAIRE

    Costa, Carlos Casimiro da; Costa, Jacinta Casimiro da

    2012-01-01

    Tomorrow, I m recovering my Thursday child as an absolute beginner , Transporting you to the essential touch of surface skin and space, Only for you, i do not regret, looking for education in a materia set. My love is your love , my materiality is you making things, The legacy of our ethnography, craftsmen s old and disappear, make me strong hard feelings, Recovering experiences and knowledge sprinkled in powder of stone, wood and metal ( ) reflecting in your dirty face the ...

  2. The pilot survey result on the radioactive concentration measurement in charcoal filter waste

    International Nuclear Information System (INIS)

    10 336 drams (50 L dram) of granular active carbon, which were taken out from charcoal filters used in medical institutions, are stored at the Kaya Memorial Takizawa Laboratory. Samples were taken from 728 drams of them and radioactive concentration was measured. Measured results of gamma-emitting radionuclides in all the samples were below the minimum detection limit. (author)

  3. Rye bran: A standard for measuring the natural radioactivity in food

    International Nuclear Information System (INIS)

    The radionuclides Cs-137, Sr-90, and K-40 are detectable in the samples with a sufficiently high activity concentration, and in homogeneous distribution. Rye bran is very suitable for an interlaboratory test for determining the above nuclides. This applies both to direct radioactivity measurement in 1 kg of dry rye bran, and to measurement on rye bran after dry ashing. (orig./DG)

  4. LOWRAD 96. Methods and applications of low-level radioactivity measurements. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Fietz, J. [ed.] [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany)

    1997-03-01

    The newest developments in the field of low-level radioactivity measurements and new applications for existing and low-level measuring facilities are presented. The contributions mostly were devoted to basic physical aspects and applications of low-level counting. Papers on chemical separation and preparation techniques and on low-level radiation dose determinations were also presented. (DG)

  5. LOWRAD 96. Methods and applications of low-level radioactivity measurements. Proceedings

    International Nuclear Information System (INIS)

    The newest developments in the field of low-level radioactivity measurements and new applications for existing and low-level measuring facilities are presented. The contributions mostly were devoted to basic physical aspects and applications of low-level counting. Papers on chemical separation and preparation techniques and on low-level radiation dose determinations were also presented. (DG)

  6. Method and apparatus for measurement of gamma-radiation of radioactive precipitate in liquid samples

    International Nuclear Information System (INIS)

    Liquid samples containing radioactive precipitate are measured separately in a sequence, the partial results are summarized by a recording system. The device consists of a transportation unit for the precipitates on filters, of a filtration unit and a radiation-measuring unit. (EG)

  7. Device for measuring the two-dimensional distribution of a radioactive substance on a surface

    International Nuclear Information System (INIS)

    A device is described by which, using a one-dimensional measuring proportional counter tube depending on position, one can measure the two-dimensionally distributed radioactivity of a surface and can plot this to scale two-dimensionally, after computer processing, or can show it two-dimensionally on a monitor. (orig.)

  8. Result of measuring inner radioactive contamination of people due to the Chernobyl accident

    International Nuclear Information System (INIS)

    A survey of results of about 140 measurements of internal radioactive contamination of Dutch people in consequence of the Chernobylsk accident is presented. The measurements were performed with total body counters by the Dutch Institute for Radiopathology and Radiation Protection (IRS) and the Radiologic Department TNO (RD-TNO). 4 figs.; 3 tabs

  9. Measurement of the absolute Quantum Efficiency of Hamamatsu model R11410-10 photomultiplier tubes at low temperatures down to liquid xenon boiling point

    OpenAIRE

    Lyashenko, Alexey; Nguyen, Tam; Snyder, Adam; Wang, Hanguo; Arisaka, Katsushi

    2014-01-01

    We report on the measurements of the absolute Quantum Efficiency(QE) for Hamamatsu model R11410-10 PMTs specially designed for the use in low background liquid xenon detectors. QE was measured for five PMTs in a spectral range between 154.5 nm to 400 nm at low temperatures down to -110$^0$C. It was shown that during the PMT cooldown from room temperature to -110 $^0$C (a typical PMT operation temperature in liquid xenon detectors), the absolute QE increases by a factor of 1....

  10. Proposal to streamlined measurement of radioactivity in working environment based on the amount of radioisotopes handled

    International Nuclear Information System (INIS)

    All radiation facilities using unsealed radioisotopes are required to measure the concentration of radioactivity in indoor airborne every month on the basis of the“Industrial Safety and Health Law” and the“Ordinance on Prevention of Ionizing Radiation Hazards”. The indoor concentrations of radioactive substances were also calculated from the actual amounts of radioisotopes handled in Nagasaki University. Both the calculation data and the measurement data in practice were extremely well below the control level and even lower than the detection limits. These results suggest that the evidence-based efforts should be made to relax the present regulations on measurements of indoor airborne radioactivity. The possible scenario of exemption rules are discussed and proposed here. (author)

  11. Occupational exposure of phosphate mine workers: airborne radioactivity measurements and dose assessment.

    Science.gov (United States)

    Khater, Ashraf E; Hussein, M A; Hussein, Mohamed I

    2004-01-01

    Under the Egyptian program for radiation safety and control, airborne radioactivity measurements and radiological dose assessment were conducted in some phosphate and uranium mines. Abu-Tartor mine is one of the biggest underground phosphate mines in Egypt. Airborne radioactivity, radon ((222)Rn) and its short-lived decay products (progenies) and thoron ((220)Rn), were measured in selected locations along the mine. The environmental gamma and workers dose equivalent rate (mSv/y) were measured inside and outside the mine using thermo-luminescence dosimeters (TLD). The results were presented and discussed. The calculated annual effective dose due to airborne radioactivity is the main source of occupational exposure and exceeding the maximum recommended level by ICRP-60 inside the mine tunnels. A number of recommendations are suggested to control the occupational exposures. PMID:15149761

  12. Occupational exposure of phosphate mine workers: airborne radioactivity measurements and dose assessment

    International Nuclear Information System (INIS)

    Under the Egyptian program for radiation safety and control, airborne radioactivity measurements and radiological dose assessment were conducted in some phosphate and uranium mines. Abu-Tartor mine is one of the biggest underground phosphate mines in Egypt. Airborne radioactivity, radon (222Rn) and its short-lived decay products (progenies) and thoron (220Rn), were measured in selected locations along the mine. The environmental gamma and workers dose equivalent rate (mSv/y) were measured inside and outside the mine using thermo-luminescence dosimeters (TLD). The results were presented and discussed. The calculated annual effective dose due to airborne radioactivity is the main source of occupational exposure and exceeding the maximum recommended level by ICRP-60 inside the mine tunnels. A number of recommendations are suggested to control the occupational exposures

  13. A simple low-coherence interferometric sensor for absolute position measurement based on central fringe maximum identification

    International Nuclear Information System (INIS)

    In this paper, a simple low-coherence interferometric sensor for absolute position measurement based on central fringe maximum identification is presented. The channeled spectrum, captured by a commercial spectrometer, is analyzed by using an algorithm based on the fitting of the calculated autocorrelation function of the captured optical power spectrum with the sum of two Gaussian functions. The position of the central fringe is obtained directly from the separation between two fitted Gaussian functions. In order to boost the precision of such a built sensing system, the position of the maximum of the central fringe is identified by a simple algorithm. The system currently provides unambiguous measurement over a range of 200??m with a mid-range error less than 1.4?nm. In addition to this, the sensor is characterized by a very small sensing head (bare single-mode fiber with a diameter of 125??m) and by very high resistance to environmental influences, thus enabling the possibility of using a very long down-lead sensing fiber.

  14. Recommended Procedures for Measuring Radon Fluxes from Disposal Sites of Residual Radioactive Materials

    Energy Technology Data Exchange (ETDEWEB)

    Young,, J. A.; Thomas, V. W.; Jackson, P. 0.

    1983-03-01

    This report recornmenrls instrumentation and methods suitable for measuring radon fluxes emanating from covered disposal sites of residual radioactive materials such as uranium mill tailings. Problems of spatial and temporal variations in radon flux are discussed and the advantages and disadvantages of several instruments are examined. A year-long measurement program and a two rnonth measurement rnethodology are then presented based on the inherent difficulties of measuring average radon flux over a cover using the recommended instrumentation.

  15. Measurement of radioactivity in bottled drinking water in Spain.

    Science.gov (United States)

    Palomo, M; Peñalver, A; Borrull, F; Aguilar, C

    2007-10-01

    The radioactive parameters in the Spanish regulations on water intended for human consumption (law decree 140/2003) have been determined in 30 different brands of some of the most common bottled mineral waters produced and consumed in Spain. These waters are not included in this legislation but if their consumption increases, the dose of radiation in the population may also increase. After gross alpha activity, gross beta activity, gross beta without potassium contribution and tritium activity had been determined, only a few samples (16% of the samples analysed) were over the normative limit for gross alpha activity (0.1 Bq/l), whereas all the samples were below the normative limits for the other parameters. For samples with high gross alpha activity values, (226)Ra and (224)Ra were determined. The values were between 0.01 and 1.52 Bq/l, and between 0.01 and 0.38 Bq/l, respectively, so alpha activity should be considered to be of natural origin. PMID:17681801

  16. Measurement of radioactivity in bottled drinking water in Spain

    International Nuclear Information System (INIS)

    The radioactive parameters in the Spanish regulations on water intended for human consumption (law decree 140/2003) have been determined in 30 different brands of some of the most common bottled mineral waters produced and consumed in Spain. These waters are not included in this legislation but if their consumption increases, the dose of radiation in the population may also increase. After gross alpha activity, gross beta activity, gross beta without potassium contribution and tritium activity had been determined, only a few samples (16% of the samples analysed) were over the normative limit for gross alpha activity (0.1 Bq/l), whereas all the samples were below the normative limits for the other parameters. For samples with high gross alpha activity values, 226Ra and 224Ra were determined. The values were between 0.01 and 1.52 Bq/l, and between 0.01 and 0.38 Bq/l, respectively, so alpha activity should be considered to be of natural origin

  17. Measurement of radioactivity in bottled drinking water in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, M.; Penalver, A.; Borrull, F. [Unitat de Radioquimica Ambiental i Sanitaria, Universitat Rovira i Virgili, Edifici CTT-FURV, Av. Paisos Catalans 18, 43007 Tarragona (Spain); Aguilar, C. [Unitat de Radioquimica Ambiental i Sanitaria, Universitat Rovira i Virgili, Edifici CTT-FURV, Av. Paisos Catalans 18, 43007 Tarragona (Spain)], E-mail: carme.aguilar@urv.cat

    2007-10-15

    The radioactive parameters in the Spanish regulations on water intended for human consumption (law decree 140/2003) have been determined in 30 different brands of some of the most common bottled mineral waters produced and consumed in Spain. These waters are not included in this legislation but if their consumption increases, the dose of radiation in the population may also increase. After gross alpha activity, gross beta activity, gross beta without potassium contribution and tritium activity had been determined, only a few samples (16% of the samples analysed) were over the normative limit for gross alpha activity (0.1 Bq/l), whereas all the samples were below the normative limits for the other parameters. For samples with high gross alpha activity values, {sup 226}Ra and {sup 224}Ra were determined. The values were between 0.01 and 1.52 Bq/l, and between 0.01 and 0.38 Bq/l, respectively, so alpha activity should be considered to be of natural origin.

  18. Results of radioactivity measurements along the french coasts during 1986

    International Nuclear Information System (INIS)

    A number of sampling networks for the environmental monitoring of levels from radioactive waste releases from french nuclear plants have been set up by the DPS/SEAPS since 1983. Various marine and freshwater biological indicators are being collected regularly on the Channel and Mediterranean shores and at the level of the lower Rhone river. Data gathered in 1986 show the prevailing effects of the releases from La Hague reprocessing plant and Rhone waters on the Channel and the Mediterranean sea respectively. However, clear labelling due to the CHERNOBYL accident on April 26 appeared in May and afterwards; this was shown by the appearance or level increase of different radionuclides such as: 137Cs, 134Cs, 131I, 110mAg, 106Ru, 103Ru. The sampling stations on the Mediterranean eastern shore were the most affected and the impact of CHERNOBYL was still present in December. At the most contaminated station, Nice, the health consequence, taking into account the annual maximum levels, led to a fraction of 8.10-5 of the dose limit (5 mSv.y-1) recommended by the International Commission on Radiological Protection

  19. Measurement of radioactive cesium in tap water, well water and water for paddy

    International Nuclear Information System (INIS)

    Tap water, well water and water for paddy are needed everyday life, industry, agriculture, etc. Due to the accident of Fukushima Daiichi Nuclear Power Station, these waters may have been contaminated by radioactive material. We had been measured in the Ge semiconductor detector without concentrating the radioactivity of them at the time of the accident, recently has been measured water samples with concentrating radioactive cesium ion form of low concentration. We apply the concentrating method of radioactive cesium ion to collect using ammonium phosphomolybdic acid and improved this method can be easily manipulated by anyone. This method, using a natural filtration method is obtained a recovery rate of almost 100%. The method is as follows at present. 1) Filtration for collecting particulate radioactive cesium (30 min.). 2) The addition of hydrochloric acid and ammonium phosphomolybdic acid to the filtrate and stirring (30 min.). 3) Filtration (30 min.). 4) Filter paper packed in a U-8 container. 5) Measured with a Ge semiconductor detector at count time 2 hours. 6) The filtrate is neutralized with sodium bicarbonate. (author)

  20. Measurement of radioactive cesium fell on tsunami sludge in the east coast of Miyagi prefecture

    International Nuclear Information System (INIS)

    Tohoku coastal region facing Pacific Ocean covered with tsunami sludges when the Great East Japan Earthquake hit Japan, then soon radioactive materials caused by the Fukushima Daiichi nuclear power plant accident fell on there. During October and November 2011, the samples of tsunami sludge (0.005 - 0.17 m thickness) and paddy or upland soil covered by the tsunami sludge, were collected from 15 sites, and radioactivities were measured using automatic gamma counter. The maximum value of both 134Cs and 137Cs in tsunami sludges reached as much as 3500 Bq/kg, while the radioactive cesium in most soils ranged from about 1 to 31 Bq/kg. These results mean that most of radioactive cesium fell on Miyagi area stayed in the top layer (0 - 0.05 m depth). Moreover, extraction tests with a tsunami sludge having 2200 Bq/kg for both 134Cs and 137Cs showed that as much as 9% of radioactive cesium was released in ammonium oxalate (pH 3.0), while it was negligible in pure water (pH 7.0) or ammonium sulfate (pH 4.8). Thus, radioactive cesium strongly sorped in clay minerals, though six months have passed since the disaster, is not released just by rain (pH 5.6 - 7.0). (author)

  1. Daily measurements of natural and artificial radioactivity in 1962

    International Nuclear Information System (INIS)

    Daily numerical results of measures concerning ? activity of the air, either from natural, owing to thoron, of from artificial, owing to active aerosols origin, will be found in this statement. The all results are expressed in ??curie/m3 of air. Proceedings of measure and technic of standardization, which were the matter of anterior papers, have not been discussed once more here. (author)

  2. Daily measurements of natural and artificial radioactivity in 1960

    International Nuclear Information System (INIS)

    Daily numerical results of measures concerning ? activity of the air, either from natural, owing to thoron, or from artificial, owing to active aerosols origin, will be found in this statement. The all results are expressed in ??curie / m3 of air. Proceedings of measure and technic of standardization, which were the matter of anterior papers, have not been discussed once more here. (author)

  3. Precision mass measurements at TITAN with radioactive ions

    International Nuclear Information System (INIS)

    Highlights: • The TITAN facility is the sole online Penning trap mass spectrometer with charge breeding capabilities. • Use of highly charged exotic ions reduces the beam time requirements. • Threshold charge breeding was developed as a novel technique to separate isobaric species. • Recent mass measurements have been performed to investigate nuclear structure, tests of electroweak theory, and neutrino physics. -- Abstract: Measurements of the atomic mass further our understanding in many disciplines from metrology to physics beyond the standard model. The accuracy and precision of Penning trap mass spectrometry have been well demonstrated at TITAN, including measurements of neutron-rich calcium and potassium isotopes to investigate three-body forces in nuclear structure and within the island of inversion to study the mechanism of shell quenching and deformation. By charge breeding ions, TITAN has enhanced the precision of the measurement technique. The precision achieved in the measurement of the superallowed ?-emitter 74Rb in the 8+ charge state rivaled earlier measurements with singly charged ions in a fraction of the time. By breeding 78Rb to the same charge state, the ground state could be easily distinguished from the isomer. Further developments led to threshold charge breeding, which permitted capturing and measuring isobarically and elementally pure ion samples in the Penning trap. This was demonstrated via the Q-value determination of 71Ge. An overview of the TITAN facility and recent results are presented herein

  4. Measurement of radioactivity in vegetation of the Bahawalpur Division and Islamabad federal capital territory-Pakistan

    International Nuclear Information System (INIS)

    Radioactivity is present everywhere in soil wherefrom it migrates to vegetation and plants. These vegetation/fruits when taken as food result in transfer of the radioactivity to human beings which may cause health hazards. Therefore, information about the presence of radioactivity in vegetation, plants and soil is highly desirable. In this context, we have measured activity of 226Ra, 232Th, 40K and 137Cs in the vegetation samples which were collected from different towns of the Bahawalpur Division and Islamabad. From the measured activity, radium equivalent activity, internal and external hazard indices and absorbed dose rates were calculated in order to assess the health risk. Transfer factors of the above-mentioned radionuclides from soil to vegetation have also been calculated and presented in this article

  5. Comparison of a citation-based indicator and peer review for absolute and specific measures of research-group excellence

    CERN Document Server

    Mryglod, O; Holovatch, Yu; Berche, B

    2013-01-01

    Many different measures are used to assess academic research excellence and these are subject to ongoing discussion and debate within the scientometric, university-management and policy-making communities internationally. One topic of continued importance is the extent to which citation-based indicators compare with peer-review-based evaluation. Here we analyse the correlations between values of a particular citation-based impact indicator and peer-review scores in several academic disciplines, from natural to social sciences and humanities. We perform the comparison for research groups rather than for individuals. We make comparisons on two levels. At an absolute level, we compare total impact and overall strength of the group as a whole. At a specific level, we compare academic impact and quality, normalised by the size of the group. We find very high correlations at the former level for some disciplines and poor correlations at the latter level for all disciplines. This means that, although the citation-ba...

  6. Risk analysis and protective measures for occupationally workers with technologically enhanced naturally occurring radioactive materials

    International Nuclear Information System (INIS)

    Naturally occurring radionuclides are present in many natural resources. Elevated concentrations of these radionuclides are often found in certain geological materials, namely igneous rocks and ores. Human activities that exploit these resources may lead to enhanced concentrations of radionuclides (often referred to as technologically enhanced naturally occurring radioactive material (TE-NORM). Enhanced levels of natural background radiation are encountered in many occupational industrial activities involving a large number of workers. Uncontrolled activities associated with TE-NORM can contaminate the environment and pose a risk to human health. This risk can be alleviated by the adoption of controls to identify where NORM is present; and cleaning the NORM-contaminated equipment and waste management while protecting workers. The main objective of this study is to investigate the natural radioactivity and the hazard parameters in the TE-NORM samples from different industrial activities. Also to describe the models and develop the computer codes that allow one to estimate the risk of cancer resulting from any specified dose of ionizing radiation for occupationally workers in different industrial activities. The present study deals with 50 different samples. This waste generated from petroleum fields, phosphate fertilizers samples, consumer product samples from China, ceramic and zircon samples. The radon exhalation rates calculated using solid state nuclear track detector (CR-39). The value of radon exhalation rate 58.82±5.3 x103, 4.28±0.49 x103 and 0.306±0.025 x103 Bq/m2 h for scale, sludge and sand, respectively. The value of radon exhalation rate 82.67±7.98, 62.58 ±5.7, 46.16 ±3.91 and 198.51±18.68 Bq/m2 h for phosphate fertilizers samples, consumer product samples from China, ceramic and zircon samples, respectively. The 226Ra activity concentrations were 301.4±771.5, 52.1±438 and 2.56±55.37 kBq/kg for scale, sludge and sand, respectively. The 226Ra activity concentrations were 758.77±23.3, 744.47±57.4, 417.1±25.4 and 18317.4±26.9 Bq/kg for phosphate fertilizers samples, consumer product samples from China, ceramic and zircon samples, respectively.The average activity concentrations of 238U, 232Th and 40K for TE-NORM samples are higher than the world wide average value. The worldwide average values (32, 35, 45 and 420) for 226R, 238U series, 232Th series and 40K, respectively. The estimated hazard parameters in all TE-NORM samples are higher than the recommended values. The estimated average annual effective dose for both scale and sludge petroleum samples is higher than the recommended limits for occupationally worker while for the rest TE-NORM samples under investigation it is lower than the recommended values for workers. The excess relative risk and excess absolute risk of cancer are computed by special computer codes which developed for this study and tested. The obtained results proved that the workers with TENORM, in particular of oil activities, are under inevitable threat of cancer. They should be classified as occupationally radiation workers. In this study the general principles of radiation protection are primarily implemented by means of good protective measures at the workplaces. Hence, exposure control and adequate dosimetry assessment are the most critical components of a health and safety program.

  7. Multidetector-array adapter for residual radioactivity measurements

    International Nuclear Information System (INIS)

    A multidetector gamma-ray residual radioactivity system demands the development of a specific adapter to count coincidence events efficiently. The parameters to be acquired are gamma-ray energies and detection time intervals between pairs of detectors obtained through Analogue to Digital Converters (ADC) and Time Interval to Digital Converter (TDC), respectively. The data acquisition trigger must be generated internally because no external trigger, like that provided by the beam or the reaction in on-line multidetector systems, is available. The adapter that we developed intercepts the fast NIM time analogue and logical (busy and inhibit) signals from the spectroscopy amplifier and, after appropriate processing, controls the ADCs gates and generates start/stop signals for the TDC (8 input). The module implements a multilevel trigger system, each deeper level corresponding to a refined coincidence test, driven by a simple finite-state machine. The first level trigger corresponds to the detection of gamma-rays by at least two detectors in a 200 ns time window. This trigger signal, however, is not suitable to start the TDC since it is simultaneous to the last time signal. The TDC is started by the first of the time signals delayed by 200 ns in coincidence with the first level trigger. The second-level trigger consists of a majority coincidence, n > 1, of the linear amplifier busy signals with pile-up rejection, where only the detectors that triggered the adapter are taken into account. The end of conversion of all digitizers pulls the third-level trigger, causing the data acquisition to start. The logic circuits are implemented by GALs (Generic Array Logic), and delays and time coincidence windows by fast transistors. All the circuits are placed in a single printed board, although the module occupies 4 CAMAC slots due to the large number of connectors in the front panel. The ADCs controlled by this system allow to obtain energy spectra like the usual gamma coincidence ones and, in spite of the time spectra obtained by the TDC being complex, the time difference spectra of a pair of detectors is similar to that obtained by time to pulse height converters. When tested with three large volume HPGe detectors, the energy gated time resolution was 5 ns. (author)

  8. Report of results of environmental radioactivity measurement around nuclear power stations in fiscal year 1980

    International Nuclear Information System (INIS)

    In Fukushima Prefecture, the measurement of environmental radioactivity around the nuclear power stations installed or expected to be installed has been carried out since August, 1973. Also, Tokyo Electric Power Co., Inc., has carried out the measurement of environmental radioactivity in and around the Fukushima No. 1 Nuclear Power Station since February, 1968, and in and around the Fukushima No. 2 Nuclear Power Station since April, 1978. These results of measurement have been published every two months after having been evaluated and examined by the Fukushima Nuclear Power Station Security Technology Liaison Conference, and also in annual reports. In this fiscal year, surf clams were added to the fundamental plan of environmental radioactivity measurement as a new sample, based on the basic investigation of surf clams performed in the last year. In this report, the results of above mentioned measurement in fiscal year 1980 are summarized as the annual report. The radiation dose, total alpha and total beta (gamma) radioactivity concentrations were within the range of natural fluctuation. The nuclides originated from nuclear test fallout and nuclear power stations were detected in very small quantity. (Kako, I.)

  9. The BiPo detector for ultralow radioactivity measurements

    CERN Document Server

    ,

    2011-01-01

    The development of BiPo detectors is dedicated to the measurement of extremely high radiopurity in 208Tl and 214Bi for the SuperNEMO double beta decay source foils. A modular prototype, called BiPo-1, with 0.8 m2 of sensitive surface area, has been running in the Modane Underground Laboratory since February, 2008. The goal of BiPo-1 is to measure the different components of the background and in particular the surface radiopurity of the plastic scintillators that make up the detector. The first phase of data collection has been dedicated to the measurement of the radiopurity in 208Tl. After more than one year of background measurement, a surface activity of the scintillators of A(208Tl) = 1.5 \\muBq/m2 is reported here. Given this level of background, a larger BiPo3 detector having 3.25 m2 of active surface area, will able to qualify the radiopurity of the SuperNEMO selenium double beta decay foils with the required sensitivity of A(208Tl) < 3-4 \\mu Bq/kg (90% C.L.) with a six month measurement. This detect...

  10. Surveillance of radioactivity in the atmosphere by measurements and dispersion prognosis of the German meteorological service

    International Nuclear Information System (INIS)

    Based on the Strahlenschutzvorsorgegesetz (StrVG) [Precautionary Radiological Protection Act] the Deutscher Wetterdienst (DWD) [German Meteorological Service] is responsible for the measurement of radioactivity in the atmosphere as well as for dispersion prognoses. By means of the communication-network used by the Deutscher Wetterdienst and the computer-network at the Central Office at Offenbach the measured data of 40 locations are summarized and transferred to the computer-network of the 'Integriertes Mess- und Informationssystem zur Ueberwachung der Umweltradioaktivitaet' (IMIS) [Integrated Measurement and Information System for the Surveillance of Environmental Radioactivity]. The dispersion prognosis as well as the measurement data are used as first input to calculate the radiological situation. The measurement programs and the resulting products of DWD are scheduled as well as the integration of DWD in the environmental emergency response program of the World Organisation of Meteorology (WMO). (orig.)

  11. Quality audit programme for 99mTc and 131I radioactivity measurements with radionuclide calibrators

    International Nuclear Information System (INIS)

    The use of radiopharmaceuticals in nuclear medicine for diagnosis and therapy has increased over the years with 99mTc and 131I being most widely used. Quality audit programmes for radioactivity measurements of 131I have been ongoing and the 12th audit was recently conducted among seventy nuclear medicine centres (NMC) in India. An audit for the activity measurements of 99mTc was conducted for the first time among ten NMCs in Mumbai, India. These programmes for radioactivity measurements have become very important to establish traceability of measurements to national and international standards and ensure accurate calibration of radionuclide calibrators. The results of both the audits are very encouraging. Ninety-four percent of the NMCs for 131I activity measurements were within a window of ±10% and for 99mTc one NMC was deviating more than ±10%. The methodology adopted for the audit and results are discussed in detail in this paper

  12. Device for measuring bore holes using artificial radio-activity

    International Nuclear Information System (INIS)

    The borehole contains salt water or natural oil. The geophysical borehole measurement is carried out with a probe, which contains a neutron source of fast neutrons and a gamma ray detector screened with samarium oxide. The signals of neutron capture-gamma radiation from the detector from H and Cl are evaluated separately by a pulse height analyser with several channels. (RW)

  13. Measurement of airborne radioactivity from the Fukushima reactor accident in Tokushima, Japan

    CERN Document Server

    Fushimi, K; Sakama, M; Sakaguchi, Y

    2011-01-01

    The airborne radioactive isotopes from the Fukushima Daiichi nuclear plant was measured in Tokushima, western Japan. The continuous monitoring has been carried out in Tokushima. From March 23, 2011 the fission product $^{131}$I was observed. The radioisotopes $^{134}$Cs and $^{137}$Cs were also observed in the beginning of April. However the densities were extremely smaller than the Japanese regulation of radioisotopes.

  14. Questionnaire survey report on measurement of radioactivity in working environment of radioisotopes facility

    International Nuclear Information System (INIS)

    To look over the current measurement of radioactivity concentration in working environment of many radioisotopes facilities, a questionnaire survey was carried out under the auspices of the Planning Committee of the Japan Society of Radiation Safety Management. 64 responses were obtained in 128 radiation facilities, which the questionnaires were sent to. The main results were obtained by aggregate analysis of the answers for questionnaires as the followings. Major nuclides subject to measurement were 3H, 14C, 32P and 125I Sampling of radioisotopes in air was mainly performed using collectors like dust samplers and HC-collectors. Liquid scintillation counters and gamma counters were used to measure ? and ? radioactivity contained in airborne particles or gas samples. Contamination by radioactivity was not detected in 55% facilities surveyed, but in 40% facilities at the same level as or at lower levels than a hundredth part of the regulated concentration limit of each nuclide. Almost all facilities is found to consider that the measurement of radioactivity concentration in working environments is not always necessary. (author)

  15. Measurement of airborne radioactivity from the Fukushima reactor accident in Tokushima, Japan

    OpenAIRE

    Fushimi, K; Nakayama, S.; Sakama, M; Sakaguchi, Y.

    2011-01-01

    The airborne radioactive isotopes from the Fukushima Daiichi nuclear plan t was measured in Tokushima, western Japan. The continuous monitoring has been carried out in Tokushima. From March 23, 2011 the fission product $^{131}$I was observed. The radioisotopes $^{134}$Cs and $^{137}$Cs were also observed in the beginning of April. However the densities were extremely smaller than the Japanese regulation of radioisotopes.

  16. Measurement of the dry deposition rates on trees by using the natural radioactivity as a tracer

    International Nuclear Information System (INIS)

    Measurement of the dry deposition rates on trees by using the natural radioactivity as a tracer. The direct measurement of dry deposition fluxes into a canopy or onto single branches or leaves is difficult. The natural particle bound radioactivity in the ground-level air can be used as a tracer to gain information on this process in small scales of time and space. ?- and ?-spectroscopy of radioactive daughters of Rn and Tn deposited on filters and on leaves, needles and surrogate acceptors have been developed as highly mobile field-methods. Applying Radon daughters as tracers leads to information on deposition velocities during short time intervals. The evaluation of meteorological effects in the field thus becomes possible. The main factors influencing the deposition velocity are the particle size and the wind speed. Therefore size fractionating sampling devices and anemometer arrangements are needed, both small, light-weight and cheap. We prefered filter and impactor combinations to gain 4 size fractions suitable for radioactivity and composition measurements. The concentration values of compounds and elements have been evaluated by X-ray fluorescence and ionchromatography. Numerous results of measurements on natural leaves and surrogates are presented, showing the state of developement now attained and proving the applicability of this method. (orig.). 41 figs., 108 refs., 28 tabs

  17. Mass measurements on radioactive isotopes using the ISOLTRAP spectrometer

    CERN Document Server

    Dilling, J; Kluge, H J; Kohl, A; Lamour, E; Marx, G; Schwarz, S C; Bollen, G; Kellerbauer, A G; Moore, R B; Henry, S

    2000-01-01

    ISOLTRAP is a Penning trap mass spectrometer installed at the on line isotope separator ISOLDE at CERN. Direct measurements of the masses of short lived radio isotopes are performed using the existing triple trap system. This consists of three electromagnetic traps in tandem: a Paul trap to accumulate and bunch the 60 keV dc beam, a Penning trap for cooling and isobar separation, and a precision Penning trap for the determination of the masses by cyclotron resonance. Measurements of masses of unknown mercury isotopes and in the vicinity of doubly magic /sup 208/Pb are presented, all with an accuracy of delta m/m approximately=1*10/sup -7/. Developments to replace the Paul trap by a radiofrequency quadrupole ion guide system to increase the collection efficiency are presently under way and the status is presented. (10 refs).

  18. Preparation of reference material for the measurement of natural radioactivity

    International Nuclear Information System (INIS)

    The objective of this work is to prepare reference material for the calibration of gamma spectrometry, alpha and XRF .Many procedures of chemical preparation and radiological analysis of a reference material from Triple Superphosphate were tested. Several techniques and methods of measurement were used. In addition to a description and validation of these procedures, a study of repeatability was conducted which resulted in a positive characterization of this material.

  19. Measurement of radioactivity in activated sludge at waste water treatment plants in Tokyo

    International Nuclear Information System (INIS)

    Radioactivities in the activated sludges at 8 waste water treatment plants in Tokyo were measured. The radionuclides usually used in radiopharmaceuticals were detected at every plants. The concentrations of radioactive nuclides differed extremely in the plants, but the variation of the concentration of 131I during was small at each plant. At some plants, the concentration of a particular radionuclide such as 201Tl, 67Ga or 99mTc was high. According to this result and our previous reports, concentrations of 131I in the exhaust gases from the incineration plants are estimated to be lower than the concentration limit. (author)

  20. Radioactive Contamination Estimation from Micro-Copters or Helicopter Airborne Survey: Simulation and Real Measurements

    International Nuclear Information System (INIS)

    One of the main advantages of acquiring aero-radiometric measurements lies in the high collection rate of data over large areas and rough terrain. Typical aero-radiometric system records and saves gamma ray spectrum, correlated with the GPS derived location information in regular time intervals of one to two seconds. Such data can be used to locate radiation anomalies on the ground, map ground contamination or track a radioactive airborne plume. Acquiring spectral data of this type allows separation of natural radioactivity from that of man-made sources and identification of specific isotopes, natural or man-made