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1

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.

2012-09-01

2

Calculations of wall effect in proportional counter for absolute radioactivity measurements of gaseous radioisotopes  

International Nuclear Information System (INIS)

Count loss by wall effect was calculated with EGS4 code. Calculated results agreed well with experimental results measured with pressure extrapolation method. In this calculation AE, AP and ECUT, PCUT are better to be set at lower values. Because EGS4 code is not so suited for very low energy of beta-ray, for those samples which emit beta-rays with lower energy than 14C, EGS4 is unsuited to be used for calculation of wall effect. (J.P.N.)

1996-11-01

3

Measurement of the absolute \  

Energy Technology Data Exchange (ETDEWEB)

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.

Aunion, Jose Luis Alcaraz; /Barcelona, IFAE

2010-07-01

4

Radioactivity measurement  

International Nuclear Information System (INIS)

The radioactivity measurement in this chapter refers to nuclear analytical technique for the assessment of radioactivity in various type and form samples particularly the environmental and food samples. The following subjects are discussed: radionuclide measurement, sampling, radiochemical separation, sample preparation, radionuclide separation, source preparation, detection method - alpha counting, low background ?/? counting system, scintillation counter, alpha spectrometry, beta counting, photon counting, activity determination, statistical considerations, and quality assurance. The topic titled detection method, covers the principle, instrumentation, operational procedure and application for each method discussed

2005-01-01

5

Absolute gravity measurements in Indonesia  

Science.gov (United States)

For the purposes of the calibration of the superconducting gravimeter in Bandung and the establishment of the absolute gravity points, we have carried out absolute gravity measurements for the first time in Indonesia in November, 2002. We have been conducting a superconducting gravimeter (SG TT-70 #08) observation in Bandung since December 1997, under the cooperation between Kyoto University and the Volcanological Survey of Indonesia. It is one of the GGP observation points and the unique SG point near the equator. Hence the SG data are expected not only for the studies of solid earth dynamics but also for the studies of the fluid envelope (ocean, atmosphere, land water) in equatorial regions. However, the SG is a relative gravimeter and it inevitably requires calibration by means of an absolute gravimeter to ensure the scale factor and to determine instrumental drifts. Moreover, there was no absolute gravity point in Indonesia so far, therefore the realization of absolute gravity measurements in Indonesia had been strongly desired. We have carried out absolute gravity measurements in Bandung during Nov. 10 -19 by means of a FG5 (#210), and we obtained more than 29,000 effective drops. The gravity value newly determined at the gravity base point in Bandung is 977976701.9 uGal (1.e-8 m/s**2) and the scale factor for the SG is 52.281 uGal/V, although both values are still tentative and might be slightly revised in the future. We have also established another absolute gravity point in Yogyakarta near Merapi volcano. The absolute gravity measurements in Yogyakarta have been carried out during Nov. 22-26 and a tentative gravity value obtained is 978203091.9 uGal.

Fukuda, Y.; Higashi, T.; Takemoto, S.; Abe, M.; Sjafra, D.; Dendi, K.; Andan, A.; Doi, K.; Imanishi, Y.; Arguino, G.

2003-04-01

6

Absolute measurement of 152Eu  

International Nuclear Information System (INIS)

A new method of the absolute measurement for 152Eu was established based on the 4??-? spectroscopic anti-coincidence method. It is a coincidence counting method consisting of a 4??-counter and a Ge(Li) ?-ray detector, in which the effective counting efficiencies of the 4??-counter for ?-rays, conversion electrons, and Auger electrons were obtained by taking the intensity ratios for certain ?-rays between the single spectrum and the spectrum coincident with the pulses from the 4??-counter. First, in order to verify the method, three different methods of the absolute measurement were performed with a prepared 60Co source to find excellent agreement among the results deduced by them. Next, the 4??-? spectroscopic coincidence measurement was applied to 152Eu sources prepared by irradiating an enriched 151Eu target in a reactor. The result was compared with that obtained by the ?-ray spectrometry using a 152Eu standard source supplied by LMRI. They agreed with each other within the error of 2%. (author)

1981-01-01

7

Absolute measurement of 192Ir  

International Nuclear Information System (INIS)

The radioactivity of 192Ir has been measured with several different techniques. The conventional 4??-? coincidence results were confirmed by the 4??-?(Ge) spectroscopic coincidence method, in which a large HPGe detector [120% cf. 3''x3'' NaI(Tl)] was used to avoid low ?-efficiency problems. A well-type NaI(Tl) crystal was applied for the 4?? counting, which was very effective for such multi-? emitting nuclides. These results were in good agreement, and those of preliminary relative measurements with ionization chambers and ?-spectrometry were also in reasonable agreement

1998-09-11

8

Radioactive measurements in industry  

International Nuclear Information System (INIS)

The book reviews the industrial applications of radioactive isotopes. The introduction refreshes the reader's knowledge of radioactive decay, radioactive radiations and measuring techniques. Then the special problems of threshold detection, level indication, thickness measurements, measurements of layer thickness applying beta-reflexion, density measurements, humidity measurements, and the determination of the composition of different materials are detailed. In each chapter the principle of a given technique, the available equipment, the possibilities of controlling systems and results of concrete measurements are discussed. The last chapter deals with the practical aspects of the industrial installation of radioactive measuring systems. (L.E.)

1979-01-01

9

Measuring the absolute light yield of scintillators  

International Nuclear Information System (INIS)

The absolute light yield of four different scintillation materials measured with two photomultiplier tubes and two avalanche photodiodes is presented. Commonly, the photoelectron yields and electron-hole pair yields are corrected for the quantum efficiency of the detector, as specified by the manufacturer, to obtain the absolute photon yield. However, the effective quantum efficiency under scintillation measurement conditions is substantially higher due to back reflection. Only when back reflection is properly accounted for, the absolute photon yields obtained with the photomultipliers agree with those obtained with the photodiodes. The effect of optical coupling between the scintillator and detector is also discussed

2005-01-21

10

The class of absolute decomposable inequality measures  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

Bosmans, Kristof; Cowell, Frank

2009-01-01

11

Absolute continuity, singularity and product measures  

Directory of Open Access Journals (Sweden)

Full Text Available Conditions are given under which a product of two semifinite measures is absolutely continuous or weakly singular with respect to another product of two semifinite measures. A Lebesgue type decomposition theorem is proved for certain product measures so that the resulting measures are themselves product measures.

Roy A. Johnson

1982-01-01

12

Absolute calibration in vivo measurement systems  

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. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs

1991-01-01

13

Absolute calibration in vivo measurement systems  

Energy Technology Data Exchange (ETDEWEB)

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. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs.

Kruchten, D.A.; Hickman, D.P.

1991-02-01

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.

2009-01-11

15

Amoeba-absoluteness and projective measurability  

CERN Multimedia

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).

Brendle, J

1992-01-01

16

Precision absolute positional measurement of laser beams  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

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

2013-01-01

17

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

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

Wang Jian Qing; Yao Yan Ling; Jia Xue Wen

2003-01-01

18

Precise Measurement of the Absolute Fluorescence Yield  

International Nuclear Information System (INIS)

We present preliminary results of the absolute yield of fluorescence emission in atmospheric gases. Measurements were performed at the Fermilab Test Beam Facility with a variety of beam particles and gases. Absolute calibration of the fluorescence yield to 5% level was achieved by comparison with two known light sources - the Cherenkov light emitted by the beam particles, and a calibrated nitrogen laser. The uncertainty of the energy scale of current Ultra-High Energy Cosmic Rays experiments will be significantly improved by the AIRFLY measurement.

2011-09-22

19

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.)

1974-08-28

20

Measurement of radiation and radioactivity  

Energy Technology Data Exchange (ETDEWEB)

Studies in our laboratory on the detection and measurement of radiation and radioactivity which have been continued for the last more than twenty years are reviewed. As fundamental works, the mean free path length, energy loss and penetration ranges of electrons with a few keV in aluminum and stearic-acid monomolecular layers were measured. Gas multiplication factors in proportional counters with cylindrical- and rectangular-cathodes which have been extensively used in our works were examined experimentally and theoretically. Position-sensitive proportional counters of a charge division type were examined and found some new applications. The absolute radioactivity of ..beta..- and ..gamma..-ray emitting nuclide sources can be determined by applying 4..pi beta..-..gamma.. coincidence absorption method. The sources for 4..pi beta.. counting using an aluminum compound which brought less self-absorption of ..beta..-rays were prepared successfully. Electrical condctivity of the thin film for source backing was evaluated. A new method with a position-sensitive proportional counter was developed for absolute activity measurement of gaseous samples. There are now intensive needs for tritium surface contamination monitor and gas monitor. Recently, we succeeded in developing a proportional counter with air as counting gas, named air proportional counter, for ..beta..-ray detection and applied it to tritium surface contamination monitor and gas monitor. A hybrid spark chamber was developed to obtain the image of geometrical distribution of ..beta..-ray emitting nuclides. (author) 157 refs.

Watanabe, Tamaki; Mori, Chizuo; Miyahara, Hiroshi; Aoyama, Takahiko

1988-03-01

 
 
 
 
21

An absolute measure for a key currency  

Science.gov (United States)

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.

Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

22

A CT assisted method for absolute quantitation of internal radioactivity.  

Science.gov (United States)

A method is described for the determination of radioactivity (microCi or MBq) at an organ site within an object or patient. Using both anatomic image data (CT or MRI scans) and planar gamma camera images, activity at depth is determined using a matrix inversion method based on least squares. The result of the inversion analysis was the unknown set of n linear (uniform) activity densities representative of each organ within the phantom or patient. The problem was overdetermined since the number of unknown activity densities (microCi/cm) was much less than the number of analysis points (N) within the nuclear image. This method, defined as the CT assisted matrix inversion (CAMI) technique, was accurate to within 15% for a three "organ" plastic phantom, wherein the organs were right circular cylinders having activities of 74 to 508 microCi (or 2.74 MBq to 18.8 MBq). This accuracy included image quantitation effects, particularly assumptions concerning attenuation correction. The average absolute percent error of the estimated activity in four distinct radioactive volumes in the phantom was 9.8%. It was found that the background activity within the phantom was estimated to be too high if sampling regions near strong sources were used in the analysis (scatter effect). This was minimized by going at least 2 cm away from such sources. By applying the method to a monoclonal antibody clinical study, activities within the patient's major organs such as liver, spleen, and kidney could be estimated, even in cases where the organ could not be visualized. Here, the CAMI algorithm gave internally consistent results for the patient's left and right lung linear activity concentrations. The CAMI technique resolves the problem of tissue superimposition using depth information from 3-D CT and is applicable in cases where a number of organs overlap in the gamma camera image. Thus, the method should be generally useful to nuclear image quantitation and the estimation of absorbed radiation doses in patients. One particular application is the estimation of radiation doses in radioimmunotherapy (RIT). PMID:8947907

Liu, A; Williams, L E; Raubitschek, A A

1996-11-01

23

Detectors for absolute luminosity measurement at DAFNE  

Energy Technology Data Exchange (ETDEWEB)

Since the second half of year 2007, the Frascati {Phi}- factory DAFNE has been running with an upgraded interaction region in order to test the crabbed waist collision scheme. The aim is to reach a large improvement of the specific luminosity of the accelerator. We describe the various detectors realized to have a reliable and fast absolute luminosity measurement, the on-line analysis in order to get rid of the machine background contribution, and the performances of the system.

Valente, P., E-mail: paolo.valente@roma1.infn.i [INFN Roma, Rome (Italy); Boscolo, M.; Bossi, F.; Buonomo, B.; Mazzitelli, G.; Murtas, F.; Sensolini, G.; Raimondi, P. [INFN LNF, Frascati (Italy); Arnaud, N.; Breton, D.; Burmistrov, L.; Stocchi, A.; Variola, A.; Viaud, B. [LAL, Orsay (France); Branchini, P. [INFN Roma Tre, Rome (Italy); Schioppa, M. [INFN Cosenza, Rende (Italy)

2010-05-21

24

Detectors for absolute luminosity measurement at DAFNE  

International Nuclear Information System (INIS)

Since the second half of year 2007, the Frascati ?- factory DAFNE has been running with an upgraded interaction region in order to test the crabbed waist collision scheme. The aim is to reach a large improvement of the specific luminosity of the accelerator. We describe the various detectors realized to have a reliable and fast absolute luminosity measurement, the on-line analysis in order to get rid of the machine background contribution, and the performances of the system.

2010-05-11

25

Detectors for absolute luminosity measurement at DAFNE  

Science.gov (United States)

Since the second half of year 2007, the Frascati ?- factory DAFNE has been running with an upgraded interaction region in order to test the crabbed waist collision scheme. The aim is to reach a large improvement of the specific luminosity of the accelerator. We describe the various detectors realized to have a reliable and fast absolute luminosity measurement, the on-line analysis in order to get rid of the machine background contribution, and the performances of the system.

Valente, P.; Boscolo, M.; Bossi, F.; Buonomo, B.; Mazzitelli, G.; Murtas, F.; Sensolini, G.; Raimondi, P.; Arnaud, N.; Breton, D.; Burmistrov, L.; Stocchi, A.; Variola, A.; Viaud, B.; Branchini, P.; Schioppa, M.

2010-05-01

26

The first absolute gravity measurements in Indonesia  

Science.gov (United States)

For the purposes of the calibration of the superconducting gravimeter (SG) in Bandung and the establishment of the absolute gravity (AG) points, we carried out AG measurements for the first time in Indonesia in November 2002. The measurements in Bandung were conducted between November 15th and 20th by means of a FG5 (#210), and 14,520 effective drops were obtained. The gravity value newly determined at the AG point in Bandung is 977976701.2 ?gal (1 ?gal = 10 -8 ms -2) and the scale factor for the SG is -52.22 ?gal/V. We also established another AG point in Yogyakarta near Merapi volcano and carried out AG measurements in Yogyakarta between November 22nd and 26th. The gravity value determined for this station is 978203093.5 ?gal.

Fukuda, Yoichi; Higashi, Toshihiro; Takemoto, Shuzo; Abe, Maiko; Dwipa, Sjafra; Kusuma, Dendi Surya; Andan, Achmad; Doi, Koichiro; Imanishi, Yuichi; Arduino, Giuseppe

2004-10-01

27

MLU and IPSyn measuring absolute complexity  

Directory of Open Access Journals (Sweden)

Full Text Available This article compares the results of Mean Length of Utterance (MLU and Index of Productive Syntax (IPSyn with the structural complexity of spontaneous utterances produced by 30-month-old Finnish children in a semi-structured playing situation. The comparison was carried out in order to determine the aspects of structural complexity which can be detected with MLU and IPSyn. This research adopts the frameworks of absolute complexity together with a multidimensional view of utterance structure and, furthermore, applies it through Utterance Analysis (UA. The results of the comparison between the metrics and changes in structural complexity discovered by UA reveal that MLU and IPSyn do function as measures of structural complexity but only if used in close relation to each other. Because they focus on different aspects of utterances, the results of both metrics should be interpreted in relation to one another.DOI: http://dx.doi.org/10.5128/ERYa5.11

Lea Nieminen

2009-05-01

28

Absolute decay width measurements in 16O  

International Nuclear Information System (INIS)

The reaction 126C(63Li, d)168O* at a 6Li bombarding energy of 42 MeV has been used to populate excited states in 16O. The deuteron ejectiles were measured using the high-resolution Munich Q3D spectrograph. A large-acceptance silicon-strip detector array was used to register the recoil and break-up products. This complete kinematic set-up has enabled absolute ?-decay widths to be measured with high-resolution in the 13.9 to 15.9 MeV excitation energy regime in 16O; many for the first time. This energy region spans the 14.4 MeV four-? breakup threshold. Monte-Carlo simulations of the detector geometry and break-up processes yield detection efficiencies for the two dominant decay modes of 40% and 37% for the ?+12C(g.s.) and a+12C(2+1) break-up channels respectively.

2012-09-18

29

Absolute optical surface measurement with deflectometry  

Science.gov (United States)

Deflectometry utilises the deformation and displacement of a sample pattern after reflection from a test surface to infer the surface slopes. Differentiation of the measurement data leads to a curvature map, which is very useful for surface quality checks with sensitivity down to the nanometre range. Integration of the data allows reconstruction of the absolute surface shape, but the procedure is very error-prone because systematic errors may add up to large shape deviations. In addition, there are infinitely many combinations for slope and object distance that satisfy a given observation. One solution for this ambiguity is to include information on the object's distance. It must be known very accurately. Two laser pointers can be used for positioning the object, and we also show how a confocal chromatic distance sensor can be used to define a reference point on a smooth surface from which the integration can be started. The used integration algorithm works without symmetry constraints and is therefore suitable for free-form surfaces as well. Unlike null testing, deflectometry also determines radius of curvature (ROC) or focal lengths as a direct result of the 3D surface reconstruction. This is shown by the example of a 200 mm diameter telescope mirror, whose ROC measurements by coordinate measurement machine and deflectometry coincide to within 0.27 mm (or a sag error of 1.3?m). By the example of a diamond-turned off-axis parabolic mirror, we demonstrate that the figure measurement uncertainty comes close to a well-calibrated Fizeau interferometer.

Li, Wansong; Sandner, Marc; Gesierich, Achim; Burke, Jan

30

On The Absolute Measurement of Some Nuclear Material Samples  

International Nuclear Information System (INIS)

A state with nuclear activities should establish a system capable of controlling all nuclear material (NM) under its authority. Continuous improvement of a measuring system is an essential mandate such controlling system. Measurements of NM using absolute methods could eliminate the dependency on NM standards, which are necessary for other relative or semi-absolute methods. In this work, an absolute method was used to estimate uranium contents in some NM samples. NM was measured by an absolute method through combination of experimental measurements and Monte Carlo calculations

2010-01-01

31

Absolute measurement of neutron cross sections. Progress report  

International Nuclear Information System (INIS)

The procedures and status of the absolute measurement of the neutron capture cross sections for 115In and 232Th are described. Work on the 239Pu fission fragment anisotropy and absolute measurement of the fast neutron fission cross section for 233U are briefly described. Progress in establishing the 14 MeV neutron measurements at the facility are discussed

1981-01-01

32

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.)

1951-01-01

33

Measurement of radioactivity in rain  

International Nuclear Information System (INIS)

The report gives a description of an ion-exchange surveillance- sampler for routine measurements of radioactivity in rain, and how the measurements are performed. Using the nuclides "8"5Sr, "1"3"1I and "1"3"7Cs as tracers, experiments have been performed to determine the distribution of radioactivity in the ion-exchange column and the effectiveness of the column as a function of elutriation rate and temperature

1985-01-01

34

Detection of Absolute Motion through Measurement of Synchronization Offsets  

Directory of Open Access Journals (Sweden)

Full Text Available An absolute reference frame may be defined as the one which is stationary with respect to the center of mass of the Universe and in which speed of propagation of light is an isotropic constant. Any motion with respect to this frame may be referred as absolute motion. In this paper we examine the Sagnac effect of absolute motion in the context of clock synchronization through GPS satellites in common view mode. The e-synchronization of two clocks A and B amounts to introduction of time offsets such that the time taken by a light pulse to propagate between A and B will be measured to be the same in both directions. Synchronization of two clocks through a GPS satellite in common view mode is effectively equivalent to e-synchronization of these clocks and introduces an absolute synchronization mismatch proportional to the absolute velocity and length of the baseline. Measurement of this synchronization offset between the GPS synchronized clocks at the ends of a long baseline will enable the practical detection of absolute motion of earth. Here we propose a simple experiment for detection of absolute motion through measurement of absolute synchronization offsets between two timing laboratories maintaining UTC time.

Gurcharn Singh Sandhu

2012-10-01

35

Measuring the absolute magnetic field using high-Tc SQUID  

International Nuclear Information System (INIS)

SQUID normally can only measure the change of magnetic field instead of the absolute value of magnetic field. Using a compensation method, a mobile SQUID, which could keep locked when moving in the earth's magnetic field, was developed. Using the mobile SQUID, it was possible to measure the absolute magnetic field. The absolute value of magnetic field could be calculated from the change of the compensation output when changing the direction of the SQUID in a magnetic field. Using this method and the mobile SQUID, we successfully measured the earth's magnetic field in our laboratory

2006-06-01

36

Environmental radioactivity measurement. Ispra 1990  

International Nuclear Information System (INIS)

In this report there are briefly described the measurements of environmental radioactivity performed during 1990 by the site survey group of the Radioprotection Division at the Joint Research Centre Ispra Establishment. Data are give on the concentrations of Sr-90, Cs-137, HTO and other radionuclides in precipitation, air, waters, herbage, milk and radioactive effluents. The environmental contamination is mainly a consequence of the nuclear accident of Chernobyl

1992-01-01

37

Simple method for absolute activity measurement of 60Co source  

International Nuclear Information System (INIS)

The activity of 60Co source was measured using the full absorption, sum and random coincidence (pile-up) peaks and the total spectrum area. It is shown that if the true and random coincidences in the single detector are treated correctly, no additional data are needed for absolute source strength measurement. With the source on the detector end-cap (when the angular correlation effects are negligible), this simple method yields absolute activity values deviating from the reference activity by about 1%.

2009-05-21

38

Absolute Branching Fraction Measurements of Exclusive D^0 Semileptonic Decays  

CERN Multimedia

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.

Coan, T E; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Credé, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Phillips, E A; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stöck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S S; Müller, J A; Savinov, V; Li, Z; López, A; Méndez, H; Ramírez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shibata, E I; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H

2005-01-01

39

Absolute beam position measurement in an accelerator structure  

International Nuclear Information System (INIS)

High gradient acceleration requires exquisite control of beam position relative to the accelerating structure electrical center in order to avoid the excitation of transverse deflecting fields. We have measured such ''absolute'' beam position in a prototype X-band accelerator structure using beam induced microwave signals. We then verified our measurements independently by probing the beam excited field with a second witness bunch. Absolute beam positioning precision has been demonstrated at the level of 40 ?m. (orig.)

1998-02-21

40

Absolute Quantum Yield Measurement of Powder Samples  

Science.gov (United States)

Measurement of fluorescence quantum yield has become an important tool in the search for new solutions in the development, evaluation, quality control and research of illumination, AV equipment, organic EL material, films, filters and fluorescent probes for bio-industry. Quantum yield is calculated as the ratio of the number of photons absorbed, to the number of photons emitted by a material. The higher the quantum yield, the better the efficiency of the fluorescent material. For the measurements featured in this video, we will use the Hitachi F-7000 fluorescence spectrophotometer equipped with the Quantum Yield measuring accessory and Report Generator program. All the information provided applies to this system. Measurement of quantum yield in powder samples is performed following these steps: Generation of instrument correction factors for the excitation and emission monochromators. This is an important requirement for the correct measurement of quantum yield. It has been performed in advance for the full measurement range of the instrument and will not be shown in this video due to time limitations. Measurement of integrating sphere correction factors. The purpose of this step is to take into consideration reflectivity characteristics of the integrating sphere used for the measurements. Reference and Sample measurement using direct excitation and indirect excitation. Quantum Yield calculation using Direct and Indirect excitation. Direct excitation is when the sample is facing directly the excitation beam, which would be the normal measurement setup. However, because we use an integrating sphere, a portion of the emitted photons resulting from the sample fluorescence are reflected by the integrating sphere and will re-excite the sample, so we need to take into consideration indirect excitation. This is accomplished by measuring the sample placed in the port facing the emission monochromator, calculating indirect quantum yield and correcting the direct quantum yield calculation. Corrected quantum yield calculation. Chromaticity coordinates calculation using Report Generator program. The Hitachi F-7000 Quantum Yield Measurement System offer advantages for this application, as follows: High sensitivity (S/N ratio 800 or better RMS). Signal is the Raman band of water measured under the following conditions: Ex wavelength 350 nm, band pass Ex and Em 5 nm, response 2 sec), noise is measured at the maximum of the Raman peak. High sensitivity allows measurement of samples even with low quantum yield. Using this system we have measured quantum yields as low as 0.1 for a sample of salicylic acid and as high as 0.8 for a sample of magnesium tungstate. Highly accurate measurement with a dynamic range of 6 orders of magnitude allows for measurements of both sharp scattering peaks with high intensity, as well as broad fluorescence peaks of low intensity under the same conditions. High measuring throughput and reduced light exposure to the sample, due to a high scanning speed of up to 60,000 nm/minute and automatic shutter function. Measurement of quantum yield over a wide wavelength range from 240 to 800 nm. Accurate quantum yield measurements are the result of collecting instrument spectral response and integrating sphere correction factors before measuring the sample. Large selection of calculated parameters provided by dedicated and easy to use software. During this video we will measure sodium salicylate in powder form which is known to have a quantum yield value of 0.4 to 0.5.

Moreno, Luis A.

2012-01-01

 
 
 
 
41

Electrochemical Studies and Absolute Work Function Measurements in Gas Ambient  

Science.gov (United States)

A simple, direct and convenient method for making absolute work function measurements in gas ambient is presented. The method consists of making measurements with a kelvin probe that has been calibrated using the clean solution surface of an electrochemical half-cell. It is shown here that the outer potential of the half-cell solution surface is constant, reliable and readily reproducible. This makes the method possible. This method for making absolute work function measurements in gas ambient requires a knowledge of the absolute work function of the half-cell. This is related to the absolute half-cell potential. The absolute half-cell potential is discussed. Previous measurements of its value disagree and are controversial. The work function of clean Hg in gas ambient is studied. Using the work function of mercury as measured in vacuum as a reference, the absolute half-cell potential for the SCE (saturated calomel electrode) is measured to be E_{rm SCE}(abs) = -4.670 +/-.027 V. A carbon sample was also used as a reference to measure the SCE. The carbon sample's work function was measured in vacuum photoelectrically immediately before comparing to the SCE in gas ambient. Using this method, the absolute half-cell potential for the SCE was measured to be E _{rm SCE}(abs) = -4.635 +/-.050 V. Measurements on gold show that its work function decreases rapidly when removed from vacuum and that it is unstable in air. A study of the chi (chi) potential of solution-gas ambient surface (electrostatic potential difference across the interphase) is included. It was found that chi is constant for many different electrolyte solutions at varying concentrations. This allows liquid junction potentials to be measured. Also, an acoustically modulated kelvin probe was designed and built for use in gas ambient on liquid and solid surfaces.

Johnson, Kendall B.

42

Low-level radioactive measurements  

International Nuclear Information System (INIS)

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), and (3) to support and advice the nuclear and non-nuclear industry in matters concerning radioactive contamination. The main achievements for 1995 are in the area of the analysis of biological samples, airborne dust, as well as environmental samples (surface water, river water, soil, sediment, fish, and milk)

1996-01-01

43

Absolute measurement methods for reflectance and fluorescence  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Holopainen, Silja

2009-01-01

44

The fake of reliability measures as absolutes  

International Nuclear Information System (INIS)

It is claimed that any reliability measure defined in connection with a limit state theory of a high reliability technological system is a purely formal comparative measure of safety. It only makes sense to make comparisons wihtin classes of ''similar'' technological systems which are all accessible to the same theory. Interpretation of calculated formal failure probabilities as predictions of real failure rates are generally not justified. (orig.)

1982-08-01

45

Fake of reliability measures as absolutes  

Energy Technology Data Exchange (ETDEWEB)

It is claimed that any reliability measure defined in connection with a limit state theory of a high reliability technological system is a purely formal comparative measure of safety. It only makes sense to make comparisons wihtin classes of ''similar'' technological systems which are all accessible to the same theory. Interpretation of calculated formal failure probabilities as predictions of real failure rates are generally not justified.

Ditlevsen, O. (Danmarks Ingenioerakademi, Lyngby)

1982-08-01

46

Mass measurement of radioactive isotopes  

CERN Multimedia

The highest precision in mass measurements on short-lived radionuclides is obtained using trapping and cooling techniques. Here, the experimental storage ring (ESR) at GSI/Darmstadt and the tandem Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN play an important role. Status and recent results on mass measurements of radioactive nuclides with ESR and ISOLTRAP are summarized.

Kluge, H J; Scheidenberger, C

2004-01-01

47

Mass measurement of radioactive isotopes  

Energy Technology Data Exchange (ETDEWEB)

The highest precision in mass measurements on short-lived radionuclides is obtained using trapping and cooling techniques. Here, the experimental storage ring (ESR) at GSI/Darmstadt and the tandem Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN play an important role. Status and recent results on mass measurements of radioactive nuclides with ESR and ISOLTRAP are summarized.

Kluge, H.-J. E-mail: j.kluge@gsi.de; Blaum, K.; Scheidenberger, C

2004-10-11

48

Measurement of radioactivity in steel  

International Nuclear Information System (INIS)

Even after the control of scrap deliveries, there remains a small risk that the radioactive contaminated scrap passes the detecting devices. Therefore, the chemical laboratory takes a role to measure each heat for the absence of artificial radioactive nuclides with a gamma spectrometer equipped with NaI-detector. As the measurement must be performed in sequence with the steel production process, the allowable time for the measurement is quite limited. On the other hand, there could be still some possibility that background radiation might be present as the samples may contain some natural radioactivity. The task is how to differentiate the nature of radioactivity between naturally remaining radioactivity within safe limit and artificial nuclides present in the sample at a low level even though a very small amount of radioactivity could be detected in short time in both cases. We have set the alarm limit to 0.1 Bq/g for Co-60 as indicating nuclide. This limit is set more than 4 s (s = standard deviation) from the average background radiation. Therefore, false alarms are quite improbable. Strategy: The NaI gamma spectrometer performs a gross gamma measurement but it can not differentiate the nature of the nuclides present. If the alarm limit is hurt, the sample is measured on a high resolution gamma spectrometer with Ge-detector for identification of the gamma emitting nuclides. Calibration: Even though no appropriate international standards are adapted and no commercial measuring equipment is commercially available, the desired standard should contain Co-60 in the order of 1 to 100 Bq/g. The presence of other gamma emitting nuclides is desirable. In the Workshop we will present how to surmount this difficulty. (author)

1999-05-26

49

Measurements of Absolute Abundances in Solar Flares  

CERN Document Server

We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory (SDO). 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 $...

Warren, Harry P

2013-01-01

50

Absolute Abundance Measurements in Solar Flares  

Science.gov (United States)

We present measurements of elemental abundances in solar flares with EVE/SDO and EIS/Hinode. EVE observes both high temperature Fe emission lines Fe XV-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. Furthermore, we have compared the EVE measurements with corresponding flare observations of intermediate temperature S, Ar, Ca, and Fe emission lines taken with EIS. Our initial calculations also indicate a photospheric composition for these observations. 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 in the non-flaring corona occurs.

Warren, Harry

2014-06-01

51

Absolute Neutron Emission Measurement in Burning Plasma Experiments  

Science.gov (United States)

The absolute measurement of neutron emission rate from the whole plasma is a very important diagnostics as a fusion power monitor in fusion experimental devices with D-T or D-T operations. Here measurement techniques of time-resolved and time-integrated absolute neutron emission on the present tokamaks and ITER are reviewed. In the present tokamaks, fission chamber installed outside the vacuum vessel are very popular in the absolute neutron emission rate measurement. As well as conventional neutron monitors installed outside the vacuum vessel, in-vessel neutron monitors using micro fission chamber are proposed for the absolute neutron emission rate measurement in ITER. The neutron activation system provides time-integrated measurements of the total neutron yield with high accuracy by using well known neutron reaction cross sections, which is useful to maintain a robust measure of fusion energy production with stability and wide dynamic range. The calibration of the relation between the neutron emission rate in the whole plasma and the output of neutron monitor is the most important issue in the absolute neutron emission rate measurements. The calibration of the neutron detectors has been performed by moving a neutron source such as a 252Cf neutron or a small accelerator-based neutron generator. For the calibration in ITER, the neutron generator with neutron emission rate of 1011 s-1 or stronger is required to obtain high accuracy.

Nishitani, Takeo; Ishikawa, Masao; Kondoh, Takashi; Kusama, Yoshinori; Asai, Keisuke; Sasao, Mmamiko

2008-03-01

52

Measurement of weak radioactivity  

CERN Document Server

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

Theodorsson, P

1996-01-01

53

Measurements of Absolute Abundances in Solar Flares  

Science.gov (United States)

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.

Warren, Harry P.

2014-05-01

54

Absolute measurements with a 4 ?-counter  

International Nuclear Information System (INIS)

Measurements on standardized p-emitters have been made in a 4 it proportional flow-counter. The counter efficiency is found to be near 100 %. Absorption curves have been determined with plastic foils and aluminium. A comparison is made between the self-absorption arising in different methods of source preparation which include precipitates and the use of wetting agents The most reliable results have been obtained with sources on aluminium foils, where the foil absorption is calculated from the absorption curves and the self-absorption is supposed to be negligible for isotopes with end point energy above 0.5 MeV. The ?-emitters studied have energies ranging from 1.71 MeV (32P) to 0.167 MeV (35S). Most of them have been obtained from National Physical Laboratory and Atomic Energy Research Establishment, Harwell, England. The agreement between their calibration and our measurements is very good except in the case of Co 60

1959-01-01

55

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.)

2000-10-09

56

Apparatus for measuring radioactive emissions  

International Nuclear Information System (INIS)

Apparatus for measuring radioactive emissions from moving radioactive material comprises at least one radiation detector in a housing serving as a first radiation shield and in which at least one groove is formed to expose at least a portion of a receptor surface of the detector. The groove extends transverse to the direction of movement of the material over the detector. A second radiation shield may be located between at least a portion of the first shield and the detector. The material of the second shield is inherently less contaminated and emits secondary excitation radiation of lower energy than the first material. (author)

1979-12-21

57

Optical testing by absolute length measurement with wavelength tuning interferometer  

Science.gov (United States)

The surface shape and the absolute optical thickness of a fused-silica glass parallel plate were measured by wavelength tuning interferometry. An excess fractions method combined with the Fourier based frequency analysis removed a systematic error. The interference orders of the optical thickness fringes were finally estimated, which resulted in an accuracy of a few nanometers for the optical thickness measurement.

Hibino, Kenichi; Kim, Yangjin; Ito, Makoto

2013-05-01

58

Absolute Branching Fraction Measurements of Exclusive D^+ Semileptonic Decays  

CERN Document Server

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.

Huang, G S; Pavlunin, V; Sanghi, B; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Credé, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Phillips, E A; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Weaver, K M; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stöck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S S; Müller, J A; Savinov, V; Li, Z; López, A; Méndez, H; Ramírez, J

2005-01-01

59

Absolute measurement of the spectral reflection factor using photon detectors  

International Nuclear Information System (INIS)

The absolute reflectometer was developed on the basis of the theory for the integrating sphere. To measure monochromatic flux in the equipment a photomultiplier EMI type 9558 AM with S-20 photocathode was used. The following investigations were carried out: 1.Determination of the dependence of the photocurrent from the supply voltage of the photomultiplier. 2. Finding out the fault of the measuring system, constituted by the photomultiplier and the measuring device, according to Clark's method

1986-01-01

60

Absolute poverty measures for the developing world, 1981–2004  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We report new estimates of measures of absolute poverty for the developing world for the period 1981–2004. A clear trend decline in the percentage of people who are absolutely poor is evident, although with uneven progress across regions. We find more mixed success in reducing the total number of poor. Indeed, the developing world outside China has seen little or no sustained progress in reducing the number of poor, with rising poverty counts in some regions, notably sub-Saharan Africa. The...

Chen, Shaohua; Ravallion, Martin

2007-01-01

 
 
 
 
61

Measurement of radioactivity in Norway  

International Nuclear Information System (INIS)

A nation-wide network of seven monitoring 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 will trigger an alarm for immediate transmission. The monitoring system and field experiences in connection with its operation are described. NILU's directions in the event of radiation alarm are specified and radiation measurements for 1987 are presented

1988-01-01

62

Absolute luminosity measurements with the LHCb detector at the LHC  

CERN Document Server

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...

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

63

New pulsed photoacoustic technique for measuring absolute optical absorption coefficient  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pulsed photoacoustic spectroscopy (PAS) technique for measuring absolute optical absorption coefficient requiring no additional measurements is presented. It is based on determination of amplitude-time characteristics of PA signal generated in air surrounding sample under investigation. PA signal is excited by short laser pulse. Sample is placed in a three-chamber PA cell. Time dependence of PA signal expected in different chambers of PA cell is derived. Water absorption coefficient at IR wav...

1994-01-01

64

Absolute polarization measurement using a vector light shift.  

Science.gov (United States)

We have measured the vector light shift due to a cavity built-up optical lattice by using a variation of the Hanle effect with trapped Cs atoms, where the time-evolving population of all magnetic sublevels is measured in situ. The measurement is linearly sensitive to the electric field of the nonlinearly polarized light, which allows unprecedented sensitivity to absolute linear polarization quality, to the level of 10(-10) in fractional intensity. Our approach to measuring and improving linear polarization can be applied to electron electric dipole moment searches, optical lattice clocks, magnetometery, and quantum computing. PMID:24483655

Zhu, Kunyan; Solmeyer, Neal; Tang, Cheng; Weiss, David S

2013-12-13

65

Measurement of the absolute branching fraction for D0?K-?+  

International Nuclear Information System (INIS)

Using 1.79 fb-1 of data recorded by the CLEO II detector we have measured the absolute branching fraction for D0?K-?+. The angular correlation between the ?+ emitted in the decay D*+?D0?+, and the jet direction in e+e-?c bar c events, is used to determine the total number of inclusive D0 mesons produced from this source. The subsequent reconstruction of the decay chain D*+?D0?+,D0?K-?+ allows a measurement of the absolute D0?K-?+ branching fraction. Correcting for decay radiation in the final state, we find scrB(D0?K-?+)=[3.95±0.08(stat)±0.17(syst)]%

1993-11-08

66

Difficulties in the absolute measurement of fission cross sections  

International Nuclear Information System (INIS)

Difficulties when we plan to make an absolute fission cross section measurement with the present facility will be explained. First, the status of the fission foils now used in the experiment are compared with those in the foreign laboratories and the necessity to develop a technique to fabricate thicker foil on a thin backing is stressed. Then, the techniques which can be used when we had enough quantities of samples are discussed. The reviewed techniques are : Poenitz's associated activity method, Time correlated associate particle method (TCAPM) of Wasson's, TCAPM of Arlt's, Reference to n-p scattering cross section of Barton's and the Black neutron detector of Wasson's. Last, the absolute measurement carried out for "2"3"8U, "2"3"2Th and "2"3"7Np fission cross sections around 14 MeV with the foil activation method is presented. (author)

1986-06-01

67

Measuring absolute spectral radiance using an Erbium Doped Fibre Amplifier  

CERN Document Server

We describe a method to measure the spectral radiance of a source in an absolute way without the need of a reference. Here we give the necessary detail to allow for the device to be reproduced from standard fiber-optic components. The device is suited for fiber-optic applications at telecom wavelengths and calibration of powermeters and spectrometers at light levels from 1nW to 1uW.

Sanguinetti, Bruno; Monteiro, Fernando; Gisin, Nicolas; Zbinden, Hugo

2012-01-01

68

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

CERN Document Server

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))%.

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

69

Oblique-incidence sounder measurements with absolute propagation delay timing  

Energy Technology Data Exchange (ETDEWEB)

Timing from the Global Position Satellite (GPS) system has been applied to HF oblique incidence sounder measurements to produce ionograms whose propagation delay time scale is absolutely calibrated. Such a calibration is useful for interpreting ionograms in terms of the electron density true-height profile for the ionosphere responsible for the propagation. Use of the time variations in the shape of the electron density profile, in conjunction with an HF propagation model, is expected to provide better near-term (1-24 hour) HF propagation forecasts than are available from current updating systems, which use only the MUF. Such a capability may provide the basis for HF frequency management techniques which are more efficient than current methods. Absolute timing and other techniques applicable to automatic extraction of the electron-density profile from an ionogram will be discussed.

Daehler, M.

1990-05-03

70

Estimation of absolute renal uptake with technetium-99m dimercaptosuccinic acid: direct comparison with the radioactivity of nephrectomy specimens  

Energy Technology Data Exchange (ETDEWEB)

Context and objective: Studies using radionuclides are the most appropriate method for estimating renal function. Dimercaptosuccinic acid chelate labeled with technetium-99m ({sup 99m}Tc- DMSA) is the radiopharmaceutical of choice for high-resolution imaging of the renal cortex and estimation of the functional renal mass. The aim of this study was to evaluate a simplified method for determining the absolute renal uptake (ARU) of {sup 99m}Tc-DMSA prior to nephrectomy, using the radioactivity counts of nephrectomy specimens as the gold standard. Design and setting: Prospective study at the Division of Nuclear Medicine, Department of Radiology, Universidade Estadual de Campinas. Methods: Seventeen patients (12 females; range 22-82 years old; mean age 50.8 years old) underwent nephrectomy for various reasons. Renal scintigraphy was performed three to four hours after intravenous administration of a mean dose of 188.7 MBq (5.1 mCi) of {sup 99m}Tc-DMSA, which was done six to 24 hours before surgery. The in vivo renal uptake of {sup 99m}Tc-DMSA was determined using the radioactivity of the syringe before the injection (measured using a dose calibrator) and the images of the syringe and kidneys, obtained from a scintillation camera. After surgery, the reference value for renal uptake of {sup 99m}Tc-DMSA was determined by measuring the radioactivity of the nephrectomy specimen using the same dose calibrator. Results: The ARU measurements were very similar to those obtained using the reference method, as determined by linear regression (r-squared = 0.96). Conclusion: ARU estimation using the proposed method before nephrectomy seems to be accurate and feasible for routine use. (author)

Lima, Mariana da Cunha Lopes de; Ramos, Celso Dario; Brunetto, Sergio Quirino; Etchebehere, Elba Cristina Sa Camargo; Santos, Allan de Oliveira; Camargo, Edwaldo Eduardo [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Dept. of Radiology. Div. of Nuclear Medicine]. E-mail: mar.lima@terra.com.br; Lima, Marcelo Lopes e; Ferreira, Ubirajara; Netto Junior, Nelson Rodrigues [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Dept. of Surgery. Div. of Urology

2008-07-01

71

Quality Assurance In Radioactivity Measurements  

International Nuclear Information System (INIS)

The credibility of obtained results is ensured by the quality assurance and control. The main requisitions involved in the quality assurance of the laboratory according to the requirements of LVS EN ISO/IEC 17025:2005 are: 1) the use of calibrated equipment only; 2) the regular and long-time use of reference materials in the control of equipment; 3) the estimation of uncertainty sources and determination of uncertainties within the given interval of credibility; 4) the validation and verification. The very important requirement is regular participation in the interlaboratory intercomparison exercises that makes it possible to estimate and find possible error sources and carry out the corrective actions. The measurements of the radioactivity of Cs-137, Co-60, H-3, the natural radioactive nuclides as well as other radionuclides in different environmental (soil, precipitation, different types of water, needles, et al.) samples, and in various radioactive polluted objects are carried out in the Laboratory of Radiation physics. The quality assurance system was implemented in our laboratory in 2000. Since 1999 laboratory is regular participant in the interlaboratory intercomparison exercises, organized by the RISO National Laboratory (Denmark) and IAEA (Vienna). The paper shows the laboratory's system of quality assurance and its implementation. We have the internal quality audit program that takes into account the requirements of LVS EN ISO/IEC 17025: 2005, but the main attention is paid to the intercomparison of the results of analyses of laboratories, their evaluation and interpretation. Only credible and justified results can be the basis for further use in any field, thus making it possible to make legitimate decisions. (Authors)

2007-05-10

72

Carbon clusters for absolute mass measurements at ISOLTRAP  

International Nuclear Information System (INIS)

The cyclotron frequencies of singly charged carbon clusters Cn+ (n?2) were measured with the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The present limit of mass accuracy ?m/m=1.2.10-8 and the extent of the mass-dependent systematic shift (?m/m)sys=1.7(0.6).10-10/u.(m-m ref) of the setup were investigated for the first time. In addition, absolute mass measurements by use of pure clusters of the most abundant carbon isotope 12C are now possible at ISOLTRAP. (orig.)

2001-07-02

73

Carbon clusters for absolute mass measurements at ISOLTRAP  

CERN Multimedia

The cyclotron frequencies of singly charged carbon clusters C/sub n //sup +/ (n >or= 2) were measured with the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The present limit of mass accuracy delta m/m = 1.2.10/sup -8/ and the extent of the mass- dependent systematic shift ( delta m/m)/sub sys/ = 1.7(0.6).10/sup -10//u.(m - m/sub ref/) of the setup were investigated for the first time. In addition, absolute mass measurements by use of pure clusters of the most abundant carbon isotope /sup 12/C are now possible at ISOLTRAP. (15 refs).

Blaum, K; Herfurth, F; Kellerbauer, A G; Kluge, H J; Kuckein, M; Sauvan, E; Scheidenberger, C; Schweikhard, L; 10.1140/epja/i2001-10262-4

2002-01-01

74

Absolute measurements of photon emission probabilities of 169Yb  

International Nuclear Information System (INIS)

A solution of 169Yb was absolutely standardized by the 4?(EC,X)-? coincidence counting method and the result was used to obtain direct measurements of gamma-ray emission probabilities with a coaxial HPGe detector. The empirical relation proposed by (Vano, F., Gonzalez, L., Gaeta R., Gonzalez, J.A., 1975. An empirical function which relates the slope of the Ge efficiency curves and the active volume Nucl. Instr. Meth. 123, 573) was tested using the gamma spectral response above 200 keV. The half-life of 169Yb was also measured with a 4?? ionization chamber

2001-03-01

75

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.)

1997-03-28

76

Measurement of Radioactivity in Some Croatian Regions  

International Nuclear Information System (INIS)

Full text: After Government of Canada expressed its suspicion that Canadian soldiers who were included in UNPROFOR mission in Croatia were exposed to increased radioactivity and possible some chemical influences, a large action of measuring and sampling was undertaken. Canadian and Croatian experts were working together and a very large number of samples was collected. Measurements of alpha, beta and gamma radioactivity on terrain, as well as later analysis of samples showed no increased radioactivity or any other signs of radioactive contamination. The conclusion is that any possible diseases of Canadian soldiers can not originate from radiation or radioactive contamination in Croatia. (author)

2001-05-20

77

Environmental radioactivity. Measurement and monitoring; Umweltradioaktivitaet. Messung und Ueberwachung  

Energy Technology Data Exchange (ETDEWEB)

The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

NONE

2009-11-15

78

Absolute flux measurement at HIGS using Compton backscattering  

Science.gov (United States)

The High Intensity ?-ray Source (HI?S) at FELL/TUNL is developing a program to study many aspects of nuclear physics presently using 2-to-50 MeV ?-rays. In many cases these experiments require absolute ?-flux monitoring and determination. This project presents a technique to indirectly measure the absolute ?-ray flux by placing a thin scattering foil in the ?-beam and then detecting the Compton-scattered ?-rays at a particular scattering angle using a HPGe detector. The fluxes of these Compton-scattered ?-rays are low (i.e., 10^3 ?/s) in comparison to the direct flux of the beam ( ˜10^6 ?/s). In addition the Compton-scattered energies are in the energy range of 2 to 5 MeV for ?-ray beam energies below 10 MeV, which are relatively easy to measure with a HPGe detector with very high energy resolution. Recent experimental results from the flux measurements at HI?S will be presented.

Fallin, B.; Ahmed, M. W.; Perdue, B.; Sabourov, A.; Sheard, T.; Tornow, W.; Tonchev, A. P.; Weller, H. R.; Li, J.; Pinaev, I. V.; Wu, Y.; Prior, R. M.; Spraker, M.; Chen, J.; Feldman, G.

2003-10-01

79

Full field imaging based instantaneous hyperspectral absolute refractive index measurement  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2012-01-01

80

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)

1990-01-01

 
 
 
 
81

Absolute fission ratio measurements with semi-conductor fission chambers  

International Nuclear Information System (INIS)

For the purpose of measuring absolute fission ratios in fast critical assemblies, fission chambers using semi-conductor detectors were prepared. By electrical deposition, thin homogeneous foils of U-233, U-235, natural uranium and neptunium-237 were obtained. The effective number of fissile atoms was determined both by alpha particle countings and by fission event recordings in standard thermal neutron column. Except for natural uranium chambers the determined effective number of atoms agreed within experimental errors. The detectors were used to measure equilibrium spectrum in the natural uranium blocks and the fast reactor spectrum in a fast critical core (FCA VI-2). The results were compared with those of other laboratories and those of calculation. It was found that the fission chambers of this type would be of practical use in fast reactor critical experiment. (auth.)

1976-01-01

82

External Raman standard for absolute intensity and concentration measurements  

International Nuclear Information System (INIS)

A new method of calibrating Raman intensities is described, which uses a sapphire window as an external intensity standard. This method overcomes problems often encountered using conventional internal standards techniques, resulting either from refractive index differences or chemical interactions of the standard with the sample. The new method is demonstrated by measuring solution concentrations and Raman cross sections in various liquids. Concentration measurements are performed using the second derivative variance minimization (SDVM) algorithm to simultaneously subtract the sapphire window spectrum, normalize the solution spectral intensity and quantify solute concentration. The absolute Raman cross sections of several pure liquids were determined by comparing intensities of the sapphire-normalized Raman bands to that of benzene and other liquids whose Raman cross sections are known

2005-03-01

83

External Raman standard for absolute intensity and concentration measurements  

Science.gov (United States)

A new method of calibrating Raman intensities is described, which uses a sapphire window as an external intensity standard. This method overcomes problems often encountered using conventional internal standards techniques, resulting either from refractive index differences or chemical interactions of the standard with the sample. The new method is demonstrated by measuring solution concentrations and Raman cross sections in various liquids. Concentration measurements are performed using the second derivative variance minimization (SDVM) algorithm to simultaneously subtract the sapphire window spectrum, normalize the solution spectral intensity and quantify solute concentration. The absolute Raman cross sections of several pure liquids were determined by comparing intensities of the sapphire-normalized Raman bands to that of benzene and other liquids whose Raman cross sections are known.

Favors, Ryan N.; Jiang, Yanan; Loethen, Yvette L.; Ben-Amotz, Dor

2005-03-01

84

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.)

1983-01-01

85

Measurement of gamma radioactivity in steel  

International Nuclear Information System (INIS)

The steel industry is being confronted increasingly with radioactive scrap from dismantled nuclear facilities. The clearance and release regulations that exist around the world differ very greatly and are difficult to implement. A 'radioactivity measurement' working group has therefore been set up at VDEh to clarify how radioactive measurements can be integrated into the day-to-day production routine. Operating results obtained at Thyssen Krupp Stahl AG with a gamma-ray spectrometer indicate a possibility for the simple detection of radioactive contamination. (orig.)

1999-01-19

86

Absolute cross-section measurements of inner-shell ionization  

International Nuclear Information System (INIS)

Cross section ratios for K- and L-shell ionization of thin silver and gold targets by positron and electron impact have been determined at projectile energies of 30-70 keV. The experimental results are confirmed by calculations in plane wave Born approximation (PWBA) which include an electron exchange term and account for the deceleration or acceleration of the incident projectile in the nuclear field of the target atom. We report first absolute cross sections for K- and L-shell ionization of silver and gold targets by lepton impact in the threshold region. We have measured the corresponding cross sections for electron (e-) impact with an electron gun and the same experimental set-up. (orig.)

1994-09-01

87

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)=lambda"0/2n#betta#_2(1+K_2/2+#betta#_2THETA_2), 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.)

1983-04-15

88

Lunar eclipse photometry: absolute luminance measurements and modeling.  

Science.gov (United States)

The Moon's time-dependent luminance was determined during the 9 February 1990 and 3 March 2007 total lunar eclipses by using calibrated, industry standard photometers. After the results were corrected to unit air mass and to standard distances for both Moon and Sun, an absolute calibration was accomplished by using the Sun's known luminance and a pre-eclipse lunar albedo of approximately 13.5%. The measured minimum level of brightness in the total phase of both eclipses was relatively high, namely -3.32 m(vis) and -1.7 m(vis), which hints at the absence of pronounced stratospheric aerosol. The light curves were modeled in such a way as to let the Moon move through an artificial Earth shadow composed of a multitude of disk and ring zones, containing a relative luminance data set from an atmospheric radiative transfer calculation. PMID:19037352

Hernitschek, Nina; Schmidt, Elmar; Vollmer, Michael

2008-12-01

89

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)

1964-01-01

90

Absolute measurements of the thermal neutron flux by the foil activation method using the 4??-? coincidence technique  

International Nuclear Information System (INIS)

An analysis of the correction factors required for the ?-? coincidence method is presented together with a listing of the various formulae involved in the determination of radioactive sources. The detection system including the activation detectores are described and the results are shown for the absolute measurements of thermal neutron flux carried out in the core of the Argonaut Reactor, at Instituto de Engenharia Nuclear (IEN), Brazil. (Author)

1977-01-01

91

On measuring the absolute scale of baryon acoustic oscillations  

CERN Document Server

The baryon acoustic oscillation (BAO) feature in the distribution of galaxies provides a fundamental standard ruler which is widely used to constrain cosmological parameters. In most analyses, the comoving length of the ruler is inferred from a combination of CMB observations and theory. However, this inferred length may be biased by various non-standard effects in early universe physics; this can lead to biased inferences of cosmological parameters such as H_0, \\Omega_m and w, so it would be valuable to measure the absolute BAO length by combining a galaxy redshift survey and a suitable direct low-z distance measurement. One obstacle is that low-redshift BAO surveys mainly constrain the ratio r_S / D_V(z), where D_V is a dilation scale which is not directly observable by standard candles. Here, we find a new approximation D_V(z) \\simeq (3/4) D_L(4z/3) (1+ 4z/3)^{-1} (1 - 0.02455 z^3 + 0.0105 z^4) which connects D_V to the standard luminosity distance D_L at a somewhat higher redshift; this is shown to be ver...

Sutherland, Will

2012-01-01

92

Absolute solar flux measurement shortward of 575 A-circle  

International Nuclear Information System (INIS)

A rare-gas ionization chamber was used to obtain an accurate measurement of the absolute solar EUV flux in the 50- to 575-A-circle region. The instrument, operating in total and near-total absorption, was flown on a solar-pointing sounding rocket on August 16, 1983. For the day of the flight the solar activity indices were F/sub 10.7/ = 132.1 and R/sub I/ = 80, and the integrated solar irradiance at the earth, corrected for atmospheric absorption, was found to be 4.31 +- 0.31 x 10"1"0 photons cm"-"2 s"-"1. Almost exactly a year earlier (August 10, 1982) the same instrument measured an integrated solar flux of 5.71 +- 0.42 x 10"1"0 photons cm"-"2 s"-"1 during a time of enhanced solar activity (F/sub 10.7/ = 209.5 and R/sub I/ = 155)

1986-06-01

93

Embedded north-seeker for automatic absolute magnetic DI measurements  

Science.gov (United States)

In magnetic observatory Earth magnetic field is recorded with a resolution of 0.1nT for 1min sampling (new standards impose 1pT for 1s sampling). The method universally adopted for measuring it is a combination of three instruments. Vectorial magnetometer (variometer) records variations of the three components around a reference value or a baseline. A proton or an overhauser magnetometer is an absolute instrument able to measure the modulus of the field and used to determine the F component baseline of the variometer. The declination and inclination baselines require a manual procedure to be computed. An operator manipulates a non-magnetic theodolite (also called a DIFlux) to measure the D and I angles in different configurations with a resolution of a few arcsec. The AutoDIF is a non-magnetic automatic DIFlux using the same protocol as the manual procedure. The declination defined according to the true north is determined by means of a target pointing system. Even if the technique is fast and accurate, it becomes problematic in case of unmanned deployment. In particular the area between the target and the DIFlux is out of control. Snow storm, fog, vegetation or condensation on windows are examples of perturbation preventing for finding the target. It is obvious in case of (future) seafloor observatories. A FOG based north-seeker has been implemented and mounted on the AutoDIF. The first results using a low cost gyro don't meet the Intermagnet specifications yet but are however hopeful. A 0.1° standard deviation has been reached and statistically reduced to 0.01° after less than two days in laboratory. The magnetic disturbance of the sensor is taken into account and compensated by the measurement protocol.

Gonsette, Alexandre; Rasson, Jean

2014-05-01

94

ATLAS ALFA—measuring absolute luminosity with scintillating fibres  

CERN Document Server

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...

Franz, S

2009-01-01

95

Measurement of environmental radioactivity. Ispra 1977  

International Nuclear Information System (INIS)

In this report there are briefly described the measurements of environmental radioactivity performed during 1977 by the site survey group of the Protection Division of the Euratom joint Research Centre - Ispra Establishement. Data are given on the concentrations of 90Sr, 137Cs and other radionuclides in precipitation, air, waters, herbage, milk and radioactive effluents. The environmental contamination is mainly world-wide fall out

1979-01-01

96

Measurement of environmental radioactivity. Ispra 1976  

International Nuclear Information System (INIS)

In this report there are briefly described the measurements of environmental radioactivity performed during 1976 by the site survey group of the Protection Division of the Euratom Joint Research Centre - Ispra Establisment. Data are given on the concentrations of 90Sr, 137Cs and other radionuclides in precipitation, air, waters, herbage milk and radioactive effluents. The environmental contamination is mainly world-wide fall out

1977-01-01

97

Relative Gravity Measurement Campaign during the 8th International Comparison of Absolute Gravimeters (2009)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The 8th International Comparison of Absolute Gravimeters (ICAG-2009) and the associated Relative Gravity Campaign (RGC2009) took place at the Bureau International des Poids et Mesures (BIPM) between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters and 9 relative gravimeters participated in the ICAG/RGC campaign. Accurate absolute and relative gravity measurements as well as precision levelling measurements were performed on the micro-gravity 3D-grid at the BIPM. Th...

Jiang, Zhiheng; Palinkas, V.; Francis, O.; Jousset, Philippe; Ma?kinen, J.; Merlet, Se?bastien; Becker, M.; Coulomb, A.; Kessler-schulz, K. U.; Schulz, H. R.; Rothleitner, Ch; Tisserand, L.; Lequin, Delphine

2012-01-01

98

NKS 1999 intercomparison of measurements of radioactivity  

International Nuclear Information System (INIS)

34 laboratories have returned radioactivity measurements on six different environmental samples. The samples were analysed for their content of gamma emitters, Sr-90, transuranics and Tc-99. The samples materials are described and the results presented. Some scatter was observed in measurements of Cs-137 in low-level samples such as dry milk, meat and hay. The scatter was less pronounced for sediments and seaweed material that had higher levels of radioactivity. In general, the most of the results were consistent with a few laboratories reporting outlying values. An exception was seawater where no clear agreement could be found for the activity of Cs-137. (au)

2000-01-01

99

NKS 1999 intercomparison of measurements of radioactivity  

Energy Technology Data Exchange (ETDEWEB)

34 laboratories have returned radioactivity measurements on six different environmental samples. The samples were analysed for their content of gamma emitters, Sr-90, transuranics and Tc-99. The samples materials are described and the results presented. Some scatter was observed in measurements of Cs-137 in low-level samples such as dry milk, meat and hay. The scatter was less pronounced for sediments and seaweed material that had higher levels of radioactivity. In general, the most of the results were consistent with a few laboratories reporting outlying values. An exception was seawater where no clear agreement could be found for the activity of Cs-137. (au)

Lange Fogh, C. [Risoe National Lab., Roskilde (Denmark)

2000-12-01

100

Comparison of available measurements of the absolute fluorescence yield  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract The uncertainty in the absolute value of the fluorescence yield is still one of the main contributions to the total error in the reconstruction of the primary energy of ultra-energetic air showers using the fluorescence technique. A significant number of experimental values of the fluorescence yield have been published in the last years, however reported results are given very often in different units (photons/MeV or photons/m) and for different wavelength intervals. In th...

2010-01-01

 
 
 
 
101

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)

1989-01-01

102

Single detector-based absolute velocity measurement using spectral domain Doppler optical coherence tomography  

Science.gov (United States)

We propose an approach for absolute velocity measurement where the use of a beam displacer provides two orthogonal linearly polarized beams to probe the sample simultaneously at two different incidence angles. The approach helps remove the cross talk image and facilitates single detector-based Fourier domain Doppler velocity measurement. The system has been characterized by quantifying absolute flow velocity in a flow phantom.

Kumar, S.; Verma, Y.; Sharma, P.; Shrimali, R.; Gupta, P. K.

2014-05-01

103

Accurate absolute measurement of trapped Cs atoms in a MOT  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish 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%.

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

104

Environmental radioactivity measurement intercomparison exercise 1990  

Energy Technology Data Exchange (ETDEWEB)

In a recent national intercomparison exercise, 49 laboratories involved in making environmental radioactivity measurements took part in the analysis of samples supplied by the National Physical Laboratory (NPL) in the United Kingdom. There were two sets of samples; one containing pure {beta}-emitters and one containing {beta}/{gamma}-emitters. Two thirds of the participants measured the {beta}/{gamma}-emitter sample only, the remainder measured both. The results are presented. (author).

Jerome, S.M. [National Physical Lab., Teddington (United Kingdom). Div. of Radiation Science and Acoustics

1991-05-01

105

Environmental radioactivity measurement intercomparison exercise 1990  

International Nuclear Information System (INIS)

In a recent national intercomparison exercise, 49 laboratories involved in making environmental radioactivity measurements took part in the analysis of samples supplied by the National Physical Laboratory (NPL) in the United Kingdom. There were two sets of samples; one containing pure ?-emitters and one containing ?/?-emitters. Two thirds of the participants measured the ?/?-emitter sample only, the remainder measured both. The results are presented. (author)

1991-01-01

106

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

1980-01-01

107

Measurement of environmental radioactivities, (1)  

International Nuclear Information System (INIS)

The specific beta activities in rice and cigarette samples have been measured by a low background beta-spectrometer. The maximum energies of the beta-rays and the specific activities for cigarette samples were almost the same, independent of their species. On the other hand, specific activities for rice sample depended on the growing districts. The activities for rices and cigarettes were 27 -- 29 pCi per piece of cigarette and 0.50 -- 1.27 pCi per gram of rice, respectively. (author)

1981-01-01

108

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)

1989-10-02

109

Nondestructive measurement of environmental radioactive strontium  

Science.gov (United States)

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.

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

2014-03-01

110

Flow measurement of blood radioactivity in animals  

International Nuclear Information System (INIS)

In order to permit flow measurement of blood radioactivity in an animal after establishing extracorporeal circulation, counting cells were constructed of various plastic scintillator materials. The cell was placed in a liquid scintillation spectrometer replacing the sample vial. Stable and reproducible counting rates were obtained only with cells made of blue Altustipe plastic. The counting efficiency was 1.8%. Using this detection system, continuous records were produced of blood radioactivity in miniature pigs after administration of 14C-urethane and [14C]methyl-piperazinyl pyrazino benzoxazepine maleate

1982-01-01

111

Radioactivity measurements as tool for physics dissemination  

International Nuclear Information System (INIS)

In general people associate environmental radioactivity with the artificial radioactivity and knows very little about natural radioactivity. Thus there is a critical need to improve nuclear physics public education. From 2005 in Italy two programs were promoted from Ministry of Education and University and National Institute of Nuclear Physics (INFN) for scientific dissemination in the field of environmental radioactivity. High school students in many Italian regions were involved in particular in indoor radon measurements. With this program students acquired awareness about the risks of inhalation of radon and its progeny and at the same time contributed to carry out radon monitoring, participating to all the experimental phases, from detectors set-up to data analysis. In particular we report about the activities carried out at Catania University and INFN division regarding a survey in the eastern Sicily. The overall monitoring, spanned over a period of 5 years, was carried out using passive nuclear track detection technique, through CR-39 dosimeters. In total about 500 detectors were placed in dwellings and schools in 57 locations. The investigated area have shown medium-high indoor radon concentrations, higher than the Italian average (70 Bq/m3). From the evaluation of the participating teachers and students, this kind of activities represents a successful strategy to enhance dissemination of physics, in particular in radioactivity topics. (author)

2014-01-01

112

Gravity measurements with a portable absolute gravimeter A10 in Syowa Station and Langhovde, East Antarctica  

Science.gov (United States)

Absolute gravity values were measured with a portable absolute gravimeter A10 in East Antarctica, for the first time by the Japanese Antarctic Research Expedition. This study aims to investigate regional spatiotemporal variations of ice mass distributions and associated crustal deformations around Syowa Station by means of repeated absolute gravity measurements, and we obtained the first absolute gravity value in Southern Langhovde on the Antarctic Continent. The average absolute gravity value at the newly installed benchmark AGS01 in Langhovde (obtained on 3 February 2012) was 982535584.2 ± 0.7 ?gal (1 [?gal] = 1 × 10-8 [m/s2]), which was in agreement with the gravity values obtained by the past relative gravity measurements within 1 mgal. In addition, the average absolute gravity value obtained at AGSaux in Syowa Station was consistent with both previous absolute gravity values and those obtained by simultaneous measurements using an FG5 gravimeter, owing to adequate data corrections associated with tidal effects and time variations in atomic clock frequencies. In order to detect the gravity changes associated with the ice mass changes and other tectonic phenomena, we plan to conduct absolute gravity measurements at AGS01 again and at other campaign sites around Syowa Station as well in the near future, with careful attention paid to the impacts of severe environmental conditions in Antarctica on gravity data collection.

Kazama, Takahito; Hayakawa, Hideaki; Higashi, Toshihiro; Ohsono, Shingo; Iwanami, Shunsuke; Hanyu, Tomoko; Ohta, Harumi; Doi, Koichiro; Aoyama, Yuichi; Fukuda, Yoichi; Nishijima, Jun; Shibuya, Kazuo

2013-09-01

113

Measurement of environmental radioactivity in Toki district  

International Nuclear Information System (INIS)

When the Institute of Plasma Physics, Nagoya University, expressed the hope to move into Toki district, the environmental problems accompanying the movement were discussed. The effect of the radioactivity leaking from the nuclear facility on human bodies must be far smaller than that of natural radiation, and for the purpose, the amount and fluctuation range of the natural radiation in the district must be known. The initial objectives of this cooperative research were to study on environmental radiation and to make a Geiger counter for the measurement. In 1981, a scintillation counter will be completed, and using a multi-channel pulse height analyzer, the nuclides which are the source of environmental radiation emission will be identified, and the tritium in natural water will be detected. Thus, the evaluation of environmental radiation can be carried out, and the situation before the movement of the research facility can be grasped. In this paper, the natural radioactivity in earth, atmosphere and water and cosmic ray, artificial radioactivity, and environmental radiation exposure dose are reported. Also, the manufacture of a GM counter measuring instrument and the measurements of cosmic ray background, typical earth samples and environmental radioactivity with the GM counter are reported. The related data are attached. (Kako, I.)

1981-01-01

114

An absolute cavity pyrgeometer to measure the absolute outdoor longwave irradiance with traceability to international system of units, SI  

Science.gov (United States)

This article describes a method of measuring the absolute outdoor longwave irradiance using an absolute cavity pyrgeometer (ACP), U.S. Patent application no. 13/049, 275. The ACP consists of domeless thermopile pyrgeometer, gold-plated concentrator, temperature controller, and data acquisition. The dome was removed from the pyrgeometer to remove errors associated with dome transmittance and the dome correction factor. To avoid thermal convection and wind effect errors resulting from using a domeless thermopile, the gold-plated concentrator was placed above the thermopile. The concentrator is a dual compound parabolic concentrator (CPC) with 180° view angle to measure the outdoor incoming longwave irradiance from the atmosphere. The incoming irradiance is reflected from the specular gold surface of the CPC and concentrated on the 11 mm diameter of the pyrgeometer's blackened thermopile. The CPC's interior surface design and the resulting cavitation result in a throughput value that was characterized by the National Institute of Standards and Technology. The ACP was installed horizontally outdoor on an aluminum plate connected to the temperature controller to control the pyrgeometer's case temperature. The responsivity of the pyrgeometer's thermopile detector was determined by lowering the case temperature and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The responsivity is then used to calculate the absolute atmospheric longwave irradiance with an uncertainty estimate (U95) of ±3.96 W m-2 with traceability to the International System of Units, SI. The measured irradiance was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the Interim World Infrared Standard Group, WISG. A total of 408 readings were collected over three different nights. The calculated irradiance measured by the ACP was 1.5 W/m2 lower than that measured by the two pyrgeometers that are traceable to WISG, with a standard deviation of ±0.7 W m-2. These results suggest that the ACP design might be used for addressing the need to improve the international reference for broadband outdoor longwave irradiance measurements.

Reda, Ibrahim; Zeng, Jinan; Scheuch, Jonathan; Hanssen, Leonard; Wilthan, Boris; Myers, Daryl; Stoffel, Tom

2012-03-01

115

Modern systems for environmental radioactivity measurements  

International Nuclear Information System (INIS)

The system for environmental radioactivity measurements with automatic data transmission represents a better solution for nuclear safety assurance. The 'intelligent probe' will be of real use for surveying the environmental radioactivity. The probes work independently. They measure the dose rate and store the data in their internal memory. Many such probes can be spread all over a large area. They are able to measure dose rate from the background level up to high catastrophic levels. A central computer 'asks' periodically the probes to send their stored data. This computer stores the data from many probes over a long time. It can show in 'windows' manner the dose rate from any probe (either in a numerical or graphical way), the position on a map of every probe and the corresponding results of the measurements. In can alert, if an alarm threshold is crossed or it can print on a printer the data for any single probe. (author)

1995-12-02

116

Environmental radioactivity measurements after the Chernobyl accidents  

International Nuclear Information System (INIS)

The measurements of the environmental radioactivity performed by the Radiation Protection Division of the CCR Ispra and by the Healt Physics Service of the CRE Saluggia ENEA on samples collected in the North-Western Italy after the Chernobyl accident are here reported. The general structure of the environmental laboratories; the choice of the samples and their collection are discussed in order to plan the actions and to make the measurements comparable

1987-01-01

117

Radioactivity. Fundamentals - measurement - applications. 5. rev. and enl. ed.  

International Nuclear Information System (INIS)

Students and practicians of physics, chemistry, medicine, engineering, and environmental science need fundamental knowledge on radioactivity for their daily practice. This is what the revised and re-edited version of this book intends to provide them with. Subjects: Properties of the atomic nucleus; Radioactivity and nuclear reactions; Natural and man-made radioactive nuclides; Production of radioactive nuclides; Radioactive emitters; Interactions and measurement of ionizing radiation, Applications of radioactive nuclides; Radiation protection. (orig.)

2005-01-01

118

Measuring the absolute magnetic field using high-T{sub c} SQUID  

Energy Technology Data Exchange (ETDEWEB)

SQUID normally can only measure the change of magnetic field instead of the absolute value of magnetic field. Using a compensation method, a mobile SQUID, which could keep locked when moving in the earth's magnetic field, was developed. Using the mobile SQUID, it was possible to measure the absolute magnetic field. The absolute value of magnetic field could be calculated from the change of the compensation output when changing the direction of the SQUID in a magnetic field. Using this method and the mobile SQUID, we successfully measured the earth's magnetic field in our laboratory.

He, D F [Superconducting Materials Center, National Institute for Materials Science, 1-2- 1 Sengen, Tsukuba, 305-0047 (Japan); Itozaki, H [Superconducting Materials Center, National Institute for Materials Science, 1-2- 1 Sengen, Tsukuba, 305-0047 (Japan)

2006-06-01

119

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.)

2001-09-17

120

High precision absolute laser power measurements using a magnetically suspended rotor  

Science.gov (United States)

Improvements to a torsion pendulum technique for making radiation pressure based measurements of laser power absolutely are presented. By replacing torsion fiber suspensions with magnetic suspensions, increases in sensitivity and reduced systematic drift are possible.

Gillies, George T.; Allison, Stephen W.

1986-08-01

 
 
 
 
121

Cross-section measurements for radioactive samples  

Energy Technology Data Exchange (ETDEWEB)

The measurement of (n,p), (n,..cap alpha..) and (n,..gamma..) cross sections for radioactive nuclei is of interest to both nuclear physics and astrophysics. For example, using these reactions, properties of levels in nuclei at high excitation energies, which are difficult or impossible to study using other reactions, can be investigated. Also, reaction rates for both big-bang and stellar nucleosynthesis can be obtained from these measurements. In the past, the large background associated with the sample activity limited these types of measurements to radioisotopes with very long half-lives. The advent of the low-energy, high-intensity neutron source at the Los Alamos Neutron Scattering CEnter (LANSCE) has greatly increased the number of nuclei which can be studied. Examples of (n,p) measurements on samples with half lives as short as fifty-three days will be given. The nuclear physics and astrophysics to be learned from these data will be discussed. Additional difficulties are encountered when making (n,..gamma..) rather than (n,p) or (n,..cap alpha..) measurements. However, with a properly-designed detector, and the high peak neutron intensities now available, (n,..gamma..) measurements can be made for nuclei with half lives as short as several months. Progress on the Los Alamos (n,..gamma..) cross-section measurement program for radioactive samples will be discussed. 39 refs., 7 figs.

Koehler, P.E.; O' Brien, H.A.

1988-01-01

122

Ultra-high Precision, Absolute, Earth Gravity Measurements PhD Thesis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Within the framework of this thesis two apparatuses for an absolute measurement of gravity were designed, constructed, and tested for the purpose of detecting long-term variations of gravity, determining the absolute gravity value for metrological applications, and for research in fundamental physics. The work includes a stationary gravimeter, which functions as a highly accurate reference system and a portable gravimeter, which is aimed for field measurements. The principle these gravimeters...

Rothleitner, Christian

2008-01-01

123

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.

2011-01-01

124

Measurements of radioactive dusts in high altitude air. Analysis of seasonal change of radioactivity  

International Nuclear Information System (INIS)

It is known that the radioactivity of rains on the ground increases in early spring season. This tendency is called ''Spring Peak''. This phenomenon is considered to be caused by the seasonal movement of radioactive substances from the stratosphere to the troposphere. The radioactivity of the airborne dusts has been measured every month since FY1961 in our research section. The seasonal change of radioactivity is analyzed with the past obtained measurement data. It is found that the radioactivity increases from the autumn to the winter influenced by the jet stream and that there is the correlation between the radioactivity and the wind flow velocity. (author)

2005-07-01

125

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.)

2006-01-00

126

Accreditation of laboratories measuring environmental radioactivity  

International Nuclear Information System (INIS)

The radiological state of our environment is a strong concern for the public. The measurement of the radioactivity is an answer to this concern. The French National Network for the Measurement of Environmental Radioactivity (www.mesure-radioactivite.fr.) centralizes all the results of measurements of radioactivity in the environment on the national territory. The web-site provide an easy access to the results. Nevertheless it is needed to ensure the quality of the results obtained by the laboratories before reporting them to the web-site. A new laboratory approval system was created through an ASN decision (decision no 2008-DC-0099 of 29 april 2008), taking into account the new prerogatives granted to ASN by Act of 13 june 2006 and the modification of Public Heath Code towards the protection of individuals against the risks arising from ionising radiations in november 2007. This paper presents this new regulation by specifying the nature of the laboratories concerned and the field of approval with more than forty different kinds of approval, relating to all the environmental compartments and various radionuclide measurements (alpha, beta or gamma emitters). It also details the procedure of approval which in particular include the conformity of the practices of the laboratory to the requirements of standard ISO/CEI 17025 and the regular participation to intercomparison tests organised by IRSN. It draws up the assessment of the laboratories approved on 1 January 2010 and analyzes the distribution of approvals according to the statute of laboratories, the measurement categories and the nature of the measured environmental samples. (author)

2010-06-01

127

Groundwater measurements by means of radioactive tracers  

International Nuclear Information System (INIS)

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.)

1986-01-01

128

Absolute measurement of beam energy by Compton scattering  

International Nuclear Information System (INIS)

We propose that the energy of a relativistic electron beam can be measured by observing the Compton radiation it scatters from a resonating cavity. The radiation is to be observed at the frequency at which the intensity does not depend upon the phase of the beam relative to the rf. The measurement will give ?E/E to within 10-4 in about 10 seconds for a 1 mA beam. The number of photons can be significantly increased, and the measuring time decreased proportionately, by use of an rf wiggler in place of the cavity

1992-01-01

129

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)

1959-01-01

130

Absolute measurements of isotope amount ratios on gases  

Science.gov (United States)

The power of the theoretical formalisms based on concepts from kinetic gas theory described in Part I of this series, is demonstrated in isotope measurement results obtained for three different gases: CO2, SiF4 gas highly enriched in the 28Si isotope and a high purity neon gas of natural isotopic composition. The measurement procedure as described in this paper enables to detect various (small) anomalies in the gas mass spectrometer during the ion current measurements thus creating the opportunity to correct for themE Using these concepts which govern the isotope fractionation of the gas in the mass spectrometer and performing a calibration by means of synthesized values for isotope amount ratios, SI traceable values in terms of the derived measurement unit mol/mol can be obtained.

Valkiers, S.; Varlam, M.; Berglund, M.; Taylor, P.; Gonfiantini, R.; de Bièvre, P.

2008-01-01

131

Absolute measurements of neutron cross sections. Progress report  

International Nuclear Information System (INIS)

The measurement of the Cr(n,x)"5"2V cross section at 14.6 MeV is discussed. Included in the discussion are sample preparation, counting systems, and calibration techniques. Future projects are also discussed. 13 refs., 2 figs., 3 tabs

1985-01-01

132

An apparatus for measuring absolute electron scattering cross sections for molecular radicals  

International Nuclear Information System (INIS)

Electron collision cross sections for highly reactive CFx (x = 1–3) radicals are required to model technological plasmas. In spite of their importance to industry, experimental studies of electron interactions with CFx radicals are rarely reported in the literature. A new apparatus for measuring absolute elastic differential cross sections for molecular radicals is reported and a sample absolute cross section for the CF2 radical is presented to demonstrate the application of this experiment

2008-08-01

133

Fallout radioactivities around Fukushima measured by gamma ray spectroscopy  

International Nuclear Information System (INIS)

After the accident of Fukushima Nuclear Power Plant, the fallout radioactivity map in soils around Fukushima measured by gamma ray spectroscopy has been prepared. The examination of radioactive materials absorbed by Fukushima's people (screening) has been made. (M.H.)

2013-10-01

134

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

2002-04-01

135

An experiment of femtosecond laser absolute distance measurement by spectrally resolved interferometry  

Science.gov (United States)

An experiment of absolute distance measurement by spectrally resolved interferometry has been executed. A Ti:Sapphire femtosecond laser without stable frequency and stable phase was used as an optical source of the measurement system. It greatly simplifies the complexity of the measurement system. A Fabry-Perot Etalon made by ourselves was employed as an optical filter to pick up frequency modes from the broad bandwidth spectrum of femtosecond laser pulse. To achieve the absolute distance, a linear array CCD detector was used to get the interferometric phase information for the calculation of distance. The measurement experiment was carried out in the non-ambiguity range and ranging precision of less than 5 ?m was achieved. The result indicates that it's feasible to measure the absolute distance by spectrally resolved interferometry with a simple femtosecond laser.

Zhou, Weihu; Li, Yao; Ji, Rongyi; Xu, Yan; Liu, Deming

2013-10-01

136

Absolute measurement of laminar flow by an orthogonal excitation method in NMR tomography  

International Nuclear Information System (INIS)

A method for absolute measurement of flow quantities by excitation of a slice orthogonal to the measuring plane is presented. The developing flow profile can be imaged directly and its dynamic behaviour can be sampled and measured using the multiecho technique. Simple formulas can be derived by means of Hagen-Poiseuille's law for quantification. (orig.)

1986-01-01

137

Method for the absolute measurement of photon energies  

International Nuclear Information System (INIS)

We present a Monte Carlo study of the Compton scattering of high energy photons on atomic electrons of a 27 Al target. The calculation was done in order to estimate the potentiality of using this reaction for high precision measurements of photon energies. A computer code was developed, based on relativistic reaction kinematics in impulse approximation, accounting for the final atom kinetic energy and the internal motion of the atomic electrons. The code includes the rescattering of the emitted electron in the target material, and allows to study the influence of several geometrical parameters of the system on the accuracy with which the initial photon energy is determined. The results of the simulations show that, for high intensity photon beams, the energy of the photons can be determined with a relative accuracy of 10-3. (author)

2001-09-01

138

Absolute measurement of alkaline atoms in low density jet  

International Nuclear Information System (INIS)

In order to determine the neutral fraction of cesium vapor which is not ionized in the beam issuing from an ion thruster, a particular sensor was developed at ONERA. This probe, the sensibility of which is 6 107 atoms sec-1 was used in order to measure the variation of cesium atom flux ejected from a spherical isothermal cavity. Experiments were performed in three flow conditions caracterized by the ratio of the mean free path to the dimension of the orifice or to the diameter of the cavity. Results demonstrate that it is possible in this configuration to obtain an efflux of 5 1013 atoms sec-1 in accordance to cosine law when the mean free path is about the diameter of the spherical cavity

1973-07-09

139

Research and development activities of Mitsubishi Heavy Industries for radioactivity measurement of radioactive waste  

Energy Technology Data Exchange (ETDEWEB)

For final disposal of radioactive waste generated from nuclear power plant and fuel cycle plant, confirmation of their nuclide concentration, whether it shall meet the criteria is one of the most important item. Therefore the technology to identify the nuclide concentration must be developed. MHI have many experience in construction of nuclear power plant and fuel cycle plant, and have many knowledge of radioactive waste management and the technology for measuring their radioactivity. This report describes an overview of the radioactivity measurement technology of the radioactive waste, which have been developed by MHI. (author)

Sakashita, Akira; Nakata, Mikihiro [Mitsubishi Heavy Industries Ltd., Tokyo (Japan); Endo, Yasumi; Wakahara, Michio [Nuclear Development Corp., Omiya, Saitama (Japan)

2001-03-01

140

High accuracy, absolute, cryogenic refractive index measurements of infrared lens materials for JWST NIRCam using CHARMS  

CERN Document Server

The refractive optical design of the James Webb Space Telescope (JWST) Near Infrared Camera (NIRCam) uses three infrared materials in its lenses: LiF, BaF2, and ZnSe. In order to provide the instrument's optical designers with accurate, heretofore unavailable data for absolute refractive index based on actual cryogenic measurements, two prismatic samples of each material were measured using the cryogenic, high accuracy, refraction measuring system (CHARMS) at NASA's Goddard Space Flight Center (GSFC), densely covering the temperature range from 15 to 320 K and wavelength range from 0.4 to 5.6 microns. Data reduction methods are discussed and graphical and tabulated data for absolute refractive index, dispersion, and thermo-optic coefficient for these three materials are presented for selected wavelengths and temperatures along with estimates of index uncertainty. Coefficients for temperature-dependent Sellmeier fits of measured index are also presented with an example of their usage to predict absolute index ...

Leviton, Douglas B; Kvamme, Todd

2008-01-01

 
 
 
 
141

Low level atmospheric aerosols radioactivity measurements  

International Nuclear Information System (INIS)

The measurement of low level radioactive aerosols in the air requires the sampling of large air volumes together with the use of high performance HPGe gamma detectors systems. An aerosol sampling station (ASS-500) was installed at Instituto Tecnologico e Nuclear (Portugal) with the purpose of conducting environmental air monitoring on a continuous basis as well as aerosol related studies. The high flow rate of the station allows the detection of aerosol bound radionuclides in the air in the order of magnitude of ?Bq/m3. The activity of the aerosol samples was measured on an ultra low background well-type HPGe detector. During the same period aerodynamic size distribution measurements were carried out using a five-stage high volume cascade impactor with effective cut off diameters of 0.49, 0.95, 1.5, 3.0 and 7.2 micrometer. The main radionuclides detected in the surface air, after decay of the short lived radon and thoron progeny, were Be-7 and Pb-210. No artificial radionuclides were detected. The activity concentrations ranged from 2 to 4 mBq/m3 for Be-7 and from 0.22 to 0.34 mBq/m3 for Pb-210. The activity size distribution measurements indicate that both radionuclides were associated with submicron aerosols in the accumulation mode, being Be-7 attached to slightly larger particles, when compared to Pb-210. The continuous radiological aerosol monitoring using the ASS-500 station will allow seasonal fluctuations to be detected as well as the short and long term evolution od the atmospheric radioactivity to be assessed (author)

2001-05-01

142

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

Directory of Open Access Journals (Sweden)

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.

Leeper R.J.

2013-11-01

143

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)

2011-09-12

144

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

2013-01-01

145

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

1993-04-02

146

Radioactivity measurements for some ophthalmic glasses  

International Nuclear Information System (INIS)

The main aim of the present work is to implant the latest ICRP/IAEA recommendations related to exemption and clearness to the Ophthalmic Glass. As consumer product, glass lenses may contain trace quantities of uranium, thorium and potassium. Glass lenses under investigation were monitored for the detection of gamma rays and beta particles using radiation measuring devices. Using high purity germanium detector radioactivity concentration was estimated in Bq/kg. Activity concentration of 226 Ra, Th-232 and K-40 were determined using the energy gamma lines of 2l4Pb (352 keV), 212Pb (238 keV) and 1460 keV gamma line for 40K respectively .Experimental results showed that radioactivity concentration for radium -226 varies from 0.19 to 4.98 Bq/kg of radium-226, from to 0.18 to 2.83 Bq/kg for thorium -232 and from 0.8 to 1.13 Bq/kg for potassium. Implementing new ICRP recommendation of exemption and clearness indicated that several Ophthalmic Glass should not be in use

2007-06-01

147

Combined absolute and relative gravity measurement for microgravity monitoring in Aso volcanic field  

Science.gov (United States)

Absolute measurement with a portable A10-017 absolute gravimeter at some benchmarks in the Aso volcanic field are valuable for reducing uncertainties of regional gravity variations and will be useful for delineating the long term trends of gravity changes. A10 absolute gravimeter is a new generation of portable absolute instrument and has accuracy 10 microGal. To further the development of a high precision gravity data, we also conducted measurement using two relative gravimeter (Scintrex CG-5 [549] and LaCoste type G-1016) to be combined with an A10 absolute gravimeter. The using absolute gravimeter along with relative gravimeter can reduce drift correction factor and improve the result of gravity change data in microgravity monitoring. Microgravity monitoring is a valued tool for mapping the redistribution of subsurface mass and for assessing changes in the fluid as a dynamic process in volcanic field. Gravity changes enable the characterization of subsurface processes: i.e., the mass of the intrusion or hydrothermal flow. A key assumption behind gravity monitoring is that changes in earth's gravity reflect mass-transport processes at depth [1]. The absolute gravity network was installed at seven benchmarks using on May 2010, which re-occupied in October 2010, and June 2011. The relative gravity measurements were performed at 28 benchmarks in one month before the eruption on May 2011 and then followed by series of gravity monitoring after the eruption in every three to five months. Gravity measurements covered the area more than 60 km2 in the west side of Aso caldera. Some gravity benchmarks were measured using both absolute and relative gravimeter and is used as the reference benchmarks. In longer time period, the combined gravity method will improve the result of gravity change data for monitoring in the Aso volcanic field. As a result, the gravity changes detected the hydrothermal flow in the subsurface which has a correlation to water level fluctuation in the crater. Large residual gravity changes between the surveys of absolute and relative gravimeter are found at benchmarks around Nakadake crater. Keywords: Microgravity monitoring, Aso volcanic field References [1] Battaglia, M., J. Gottsmann, D. Carbone, and J. Fernandez, 2008, 4D volcano gravimetry: Geophysics, vol. 73 no.6, p. WA3-WA18.

Sofyan, Yayan; Nishijima, Jun; Yoshikawa, Shin; Fujimitsu, Yasuhiro; Kagiyama, Tsuneomi; Fukuda, Yoichi

2014-05-01

148

Absolute rate measurements of two-photon process of gases, liquids, and solids  

International Nuclear Information System (INIS)

Due to rapid improvements in high-power laser performance, two-photon absorption processes have become a very useful tool for studying the molecular structures of various gases, liquids and solids. However, measurements of absolute two-photon absorption cross sections were more or less ignored previously because of their small size. In this work, we obtained not only the two-photon absorption spectra, but also measurements of their absolute cross sections for various gases, liquids, and solids. 8 refs., 1 fig., 1 tab

1987-11-01

149

Comparative Test of Two Methods of Quantum Efficiency Absolute Measurement Based on Squeezed Vacuum Direct Detection  

CERN Multimedia

We realize and test in experiment a method recently proposed for measuring absolute quantum efficiency of analog photodetectors. Similarly to the traditional (Klyshko) method of absolute calibration, the new one is based on the direct detection of two-mode squeezed vacuum at the output of a traveling wave OPA. However, in the new method one measures the difference-photocurrent variance rather than the correlation function of photocurrents (number of coincidences), which makes the technique applicable for high-gain OPA. In this work we test the new method versus the traditional one for the case of photon-counting detectors where both techniques are valid.

Agafonov, I N; Iskhakov, T Sh; Penin, A N; Rytikov, G O; Shumilkina, O A

2010-01-01

150

Measurement of Radioactivity in the Human Body  

International Nuclear Information System (INIS)

A body counter with a steel room and a 4-inch-diameter by 4-inch thick Nal scintillation counter has been in operation since February 1958. It is used to control the internal contamination in people working with radioactive materials. Measurements have also been made on the natural activity in the human body. The average cesium-137/potassium ratio in a group of Swedish males was in May 1959 73 ??c per gram of body potassium and in June 1960 55 ??c per gram of body potassium. The cessation of the nuclear bomb tests has caused a decrease in the cesium level in people. This gives some information of how cesium is entering the biosphere

1960-01-01

151

Physical Measure and Absolute Continuity for One-Dimensional Center Direction  

CERN Document Server

For a class of partially hyperbolic $C^k$, $k>1$ diffeomorphisms with circle center leaves we prove existence and finiteness of physical (or Sinai-Ruelle-Bowen) measures, whose basins cover a full Lebesgue measure subset of the ambient manifold. Our conditions contain an open and dense subset of all $C^k$ partially hyperbolic skew-products on compact circle bundles. Our arguments blend ideas from the theory of Gibbs states for diffeomorphisms with mostly contracting center direction together with recent progress in the theory of cocycles over hyperbolic systems that call into play geometric properties of invariant foliations such as absolute continuity. Recent results show that absolute continuity of the center foliation is often a rigid property among volume preserving systems. We prove that this is not at all the case in the dissipative setting, where absolute continuity can even be robust.

Viana, Marcelo

2010-01-01

152

Bolus injections of measured amounts of radioactivity  

International Nuclear Information System (INIS)

Many time-based radionuclide techniques, such as glomerular filtration rate measurement (GFR), require prompt intravenous delivery of and accurately measured tracer bolus with minimal residual tracer retention at the injection site. The quality assurance aspects of two antecubital vein, quantitative injection techniques were investigated. A flush bolus technique using a tuberculin syringe piggybacked onto a 10-ml saline flush was compared to a single blood pressure cuff injection technique. Scintillation camera data for each technique were compared for bolus duration in the abdominal aorta and for residual activity at the injection site at 5 min. Bolus times were measured as the FWHM of the gamma variate fit to the abdominal aortic regional time-activity curves. Relatively little focal activity was seen in the antecubital injection site following the flush bolus: marked residual activity was seen following the blood pressure cuff injections. The injection site/arm background ratios averaged 1.3 for the flush bolus and 30.1 for the cuff technique. Although both methods allowed accurate in vitro determination of administered radioactivity, only the tuberculin syringe flush bolus technique was acceptable for time-based quantitation because of its superior in vivo characteristics

1988-01-01

153

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

1995-10-01

154

Preparation and absolute measurement of "1"4"1Ce standard solution  

International Nuclear Information System (INIS)

This paper describes in detail the preparation of "1"4"1Ce standard solution with enriched "1"4"0Ce target (99.4%) and the absolute measurement of "1"4"1Ce disintegration rate by 4??-? coincident method. The overall uncertainty of the standard solution is ± 1%

1986-01-01

155

DESIGN AND USE OF A HIGH-ACCURACY NON-CONTACT ABSOLUTE THICKNESS MEASUREMENT MACHINE  

Energy Technology Data Exchange (ETDEWEB)

Many commercial metrology systems exist for making accurate surface form and roughness measurements of nominally planar parts. However, few metrology systems exist for making accurate absolute thickness measurements. At Lawrence Livermore National Laboratory there is an increasing need for absolute thickness measurements of mesoscale parts ranging in size from 1 mm to 25 mm in diameter and 2 {micro}m to 500 {micro}m thickness. The samples of interest in this case are nominally planar parts that require absolute thickness to be known to an accuracy of better than one micrometer. An Absolute Thickness Measurement Machine (ATMM) has been designed and constructed to fulfill this requirement (see Figure 1). This article describes the design of the ATMM and the theory behind its operation including a detailed error budget. Other issues discussed involve errors associated with the sensors (non-linearity, and sensor resolution), development of the stepped thickness reference, thermal effects, and future upgrades. This research represents one of many issues involving meso-scale metrology currently under development at Lawrence Livermore National Laboratory.

Nederbragt, W; Hibbard, R; Kroll, J; Kelly, D

2005-07-27

156

Progress towards the measurement of absolute elastic electron-molecular radical scattering cross sections  

International Nuclear Information System (INIS)

We report on our progress in developing a dedicated crossed beam apparatus, for the measurement of absolute cross sections for elastic scattering of electrons from molecular radicals. Features which are original to this apparatus will be highlighted, and a discussion of its current status and future developments provided

2007-10-01

157

Superharp: A wire scanner with absolute position readout for beam energy measurement at CEBAF  

Energy Technology Data Exchange (ETDEWEB)

Superharp is an upgrade CEBAF wire scanner with absolute position readout from shaft encoder. As high precision absolute beam position probe ({Delta}x {approximately} 10{mu}m), three pairs of superharps are installed at the entrance, the mid-point, and the exit of Hall C arc beamline in beam switch yard, which will be tuned in dispersive mode as energy spectrometer performing 10{sup {minus}3} beam energy measurement. With dual sensor system: the direct current pickup and the bremsstrahlung detection electronics, beam profile can be obtained by superharp at wide beam current range from 1 {mu}A to 100 {mu}A.

Yan, C.

1994-09-07

158

Superharp: A wire scanner with absolute position readout for beam energy measurement at CEBAF  

International Nuclear Information System (INIS)

Superharp is an upgrade CEBAF wire scanner with absolute position readout from shaft encoder. As high precision absolute beam position probe (?x ? 10?m), three pairs of superharps are installed at the entrance, the mid-point, and the exit of Hall C arc beamline in beam switch yard, which will be tuned in dispersive mode as energy spectrometer performing 10-3 beam energy measurement. With dual sensor system: the direct current pickup and the bremsstrahlung detection electronics, beam profile can be obtained by superharp at wide beam current range from 1 ?A to 100 ?A

1994-01-01

159

Continuous measuring method for radioactive iodine in off-gas  

International Nuclear Information System (INIS)

In the present invention, the amount of iodine in off-gases discharged from a nuclear fuel reprocessing facility, a nuclear reactor facility, a radioactive waste facility or a facility using radioactive iodine is measured and monitored while eliminating interference due to radioactive rare gases mixed together with iodine. Namely, in the present invention, a portion of the off gases discharged from each of the facilities is continuously circulated to an adsorbing material. Energy of the radioactive iodine adsorbed to the adsorbing material is measured by a semiconductor detector simultaneously with the measurement for the energy of mixed radioactive rare gases. The energy of K ? X-rays or ?-rays of the radioactive iodine are discriminated based on the signals of the semiconductor detector by a multiple wave-height analyzer. Discrimination signals are flattened, and interference of radioactive rare gases is eliminated. The amount of radioactive iodine is thus measured continuously. As the semiconductor detector, Ge, CdTe, HgI2 or GaAs is used. According to the present invention, radioactive iodine in the off gases can be continuously measured while eliminating interference of mixed radioactive rare gases. (I.S.)

1993-11-15

160

High Accuracy, Absolute, Cryogenic Refractive Index Measurements of Infrared Lens Materials for JWST NIRCam using CHARMS  

Science.gov (United States)

The current refractive optical design of the James Webb Space Telescope (JWST) Near Infrared Camera (NIRCam) uses three infrared materials in its lenses: LiF, BaF2, and ZnSe. In order to provide the instrument s optical designers with accurate, heretofore unavailable data for absolute refractive index based on actual cryogenic measurements, two prismatic samples of each material were measured using the cryogenic, high accuracy, refraction measuring system (CHARMS) at NASA GSFC, densely covering the temperature range from 15 to 320 K and wavelength range from 0.4 to 5.6 microns. Measurement methods are discussed and graphical and tabulated data for absolute refractive index, dispersion, and thermo-optic coefficient for these three materials are presented along with estimates of uncertainty. Coefficients for second order polynomial fits of measured index to temperature are provided for many wavelengths to allow accurate interpolation of index to other wavelengths and temperatures.

Leviton, Douglas; Frey, Bradley

2005-01-01

 
 
 
 
161

Measurement of Absolute Hadronic Branching Fractions of D_s Mesons  

CERN Document Server

We report preliminary measurements of absolute hadronic branching fractions of Ds mesons determined using a double tag technique. These measurements are from 195 pb^{-1} of e+e- collisions recorded at center of mass energies near 4.17 GeV with the CLEO-c detector at CESR. We obtain absolute branching fractions for Ds+ decays to KS0 K+, K- K+ pi+, K- K+ pi+ pi-, pi+ pi+ pi-, pi+ eta, and pi+ etaprime. We discuss the problems inherent in measuring accurately the branching fraction for Ds+ to phi pi+, which is often used as a reference mode for measurement of other Ds+ branching fractions, and provide a measurement of a branching fraction that may be useful for this purpose.

Adam, N; Berkelman, K; Cassel, D G; Duboscq, J E; Ecklund, K M; 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; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Weinberger, M; Athar, S B; Patel, R; Potlia, V; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; White, E J; Wiss, J; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Smith, A; Zweber, P; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Ernst, J; Severini, H; Dytman, S A; Love, W; Savinov, V; Aquines, O; Li, Z; López, A; Mehrabyan, S S; Méndez, H; Ramírez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Blusk, S; Butt, J; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Briere, R A; Brock, I; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L

2006-01-01

162

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 "1"3"7Cs, 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 "1"3"7Cs 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 "1"3"7Cs has been modelled and the temporal variation of the depth distribution has been described. 65 refs

1997-01-01

163

Alpha radioactivity measurements in tobacco leaves  

International Nuclear Information System (INIS)

Smoking is hazardous to your health, warning labels such as this appear on every pack of cigarettes sold in the country. The link between cigarette smoke and cancer has long been established. Smokers are ten times at greater risk of developing lung cancer than that of non-smokers. Tobacco plants were grown using different types of chemical fertilizers in different amounts just before the plantation is done in some cases while after an interval of one month in other cases. The alpha radioactivity of the leaves of these plants was measured using plastic track detectors LR-115 Type-II manufactured by Kodak. Measurement of track densities (track cm-2 day) shows a variation from 15.2 track cm-2 day-1 to 38.6 track cm-2 day-1 on the upper face and 20.7 track cm-2 day-1 to 45.4 track cm-2 day-1 at the bottom face for the plants in which fertilizers were added to soil just before the plantation while it varied from 6.9 track cm-2 day-1 to 35.8 track cm-2 day-1 and 17.9 to 41.3 track cm-2day-1 respectively on the upper and bottom faces for those plants in which fertilizers were added at a later stage. These variations are on higher side as compared to the plants grown without any use of fertilizer has been established. (author)

2005-11-10

164

Radioactivity  

International Nuclear Information System (INIS)

This pedagogical document presents the origin, effects and uses of radioactivity: where does radioactivity comes from, effects on the body, measurement, protection against radiations, uses in the medical field, in the electric power industry, in the food (ionization, radio-mutagenesis, irradiations) and other industries (radiography, gauges, detectors, irradiations, tracers), and in research activities (dating, preservation of cultural objects). The document ends with some examples of irradiation levels (examples of natural radioactivity, distribution of the various sources of exposure in France). (J.S.)

2002-01-01

165

A method for measuring the absolute sensitivity of positron emission tomographic scanners  

International Nuclear Information System (INIS)

A need exists to measure the absolute sensitivity of a positron emission tomographic (PET) scanner in units of counts/s-1 per MBq-1. At present sensitivity is generally determined by measurement of a radionuclide of known concentration distributed in a water-filled cylindrical phantom, usually 20 cm in diameter. The measurement is confounded by self-attenuation of the source and scatter within the cylinder and does not give a true absolute sensitivity measurement. Due to variations in the magnitude and treatment of these factors, meaningful comparison between different manufacturer's scanners is difficult, as are comparisons between different acquisition geometries (e.g. with and without interplane septa present). A method has been developed in our laboratory that provides measurements of absolute sensitivity in air for a scanner independent of attenuation and scatter within the source. The method involves measurements of a thin-line source of fluorine 18 contained within an aluminium housing to which successive aluminium sleeves are added. The extrapolation of these measurements allows an effective counts/s-1 per MBq-1 measurement to be made for zero thickness of aluminium. Measurements have yielded absolute sensitivities of 3926±61 counts/s-1 per MBq-1 (0.39% efficiency), 5079±26 counts/s-1 MBq-1 (0.51%), and 32312±544 counts/s-1 per MBq-1 (3.2%) for a whole-body PET scanner with interplane septa and for a NeuroPET operating with and without interplane septa, respectively. (orig.)

1991-01-01

166

Introducing an Absolute Cavity Pyrgeometer for Improving the Atmospheric Longwave Irradiance Measurement (Presentation)  

Energy Technology Data Exchange (ETDEWEB)

Advancing climate change research requires accurate and traceable measurement of the atmospheric longwave irradiance. Current measurement capabilities are limited to an estimated uncertainty of larger than +/- 4 W/m2 using the interim World Infrared Standard Group (WISG). WISG is traceable to the Systeme international d'unites (SI) through blackbody calibrations. An Absolute Cavity Pyrgeometer (ACP) is being developed to measure absolute outdoor longwave irradiance with traceability to SI using the temperature scale (ITS-90) and the sky as the reference source, instead of a blackbody. The ACP was designed by NREL and optically characterized by the National Institute of Standards and Technology (NIST). Under clear-sky and stable conditions, the responsivity of the ACP is determined by lowering the temperature of the cavity and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The absolute atmospheric longwave irradiance is then calculated with an uncertainty of +/- 3.96 W/m2 with traceability to SI. The measured irradiance by the ACP was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the WISG. A total of 408 readings was collected over three different clear nights. The calculated irradiance measured by the ACP was 1.5 W/m2 lower than that measured by the two pyrgeometers that are traceable to WISG. Further development and characterization of the ACP might contribute to the effort of improving the uncertainty and traceability of WISG to SI.

Reda, I.; Hansen, L.; Zeng, J.

2012-08-01

167

Absolute measurement of the (110) scattering factor of single-crystal vanadium  

International Nuclear Information System (INIS)

An absolute measurement of the (110) scattering factor f of single-crystal vanadium has been performed using monochromatic Ag K ? radiation. The result for f (15.75 + - 0.25) agrees with a previous measurement on a powder sample and confirms that the difference between experimental crystal values and free-atom calculations for vanadium are much smaller than those for chromium. (author)

1978-01-01

168

ArtDeco: A beam deconvolution code for absolute CMB measurements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Keiha?nen, Elina; Reinecke, Martin

2012-01-01

169

Relative Gravity Measurement Campaign during the 7th International Comparison of Absolute Gravimeters (2005)  

Science.gov (United States)

Since the 1st International Comparison of Absolute Gravimeters (ICAG) and accompanying Relative Gravity Campaign (RGC) held at the BIPM in 1981, repeated ICAG-RGCs have been organized every four years. A total of 19 absolute gravimeters (AG) and 15 relative gravimeters (RG) participated in the 7th ICAG-RGC, which took place in 2005. Co-located absolute and relative gravity measurements as well as precision levelling measurements were carried out. The final version of the absolute g values of the 7th ICAG has been officially released recently. This paper is the final report of the 7th RGC and replaces the preliminary results published earlier. It covers the organization of the RGC and the data processing, analyses RG behaviour, computes g, ?g and OAG (offset of AG) and discusses their uncertainties. In preparation for the BIPM key comparison ICAG-2009, a standard data-processing procedure has been developed and installed in the BIPM ICAG-RGC software package, GraviSoft. This was used for the final data processing.

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

2009-06-01

170

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)

2006-07-01

171

Radioactivity measurements in electric power generating plants nationwide  

International Nuclear Information System (INIS)

This study was undertaken to establish levels of radioactivity nationwide. Measurement sites were in small diesel power plants and some of the major power plants, including the mothballed nuclear power plant in Bataan. Results of the ambient radioactivity measurements in the plant sites and in the immediate vicinities were within the range of worldwide values. (author). 7 refs.; 10 tabs..; 1 fig

1993-01-01

172

Time-of-flight measurements of absolute beam energy in the Fermilab linac  

International Nuclear Information System (INIS)

Measurements have been made of the absolute energy of the fourth tank of the linac by measuring the time-of-flight of individual beam bunches passing between strip-line beam monitors at the entrance and exit of each tank of the linac. Accurate time-of-flight measurements are facilitated by the fact that the beam remains well bunched between strip-line monitors in the drift region beyond the fourth tank. Cable lengths were carefully measured using time-domain reflectometry. The data for tank 4 gave the time-of-flight over a 49.17 meter drift as 395.8 (±0.5) nanoseconds. This translates into a measured ? of 0.4155. The design ? for tank 4 is 0.4141. Further measurements on other linac tanks are planned, if machine time becomes available. In addition to determination of absolute beam energy, the time-of-flight data can be used for absolute energy calibration of the magnetic spectrometer system used for detailed energy analysis of the beam. The authors plan to implement this technique on the Linac Upgrade to be installed in the summer of 1993

1993-05-17

173

Adjustment of a two-block X-ray interferometer and absolute measurement of lattice spacing  

International Nuclear Information System (INIS)

X-ray interferometer was invented in 1965 by Bonse and Hart, and it uses the lattice surface of a silicon single crystal as a three-dimensional diffraction lattice. It divides X-ray coherently, changes direction, combines and causes interference. It made for the first time the interference effect of X-ray into the usable form in macroscopic world. As an example of the application of X-ray interferometers to basic science, there is the absolute measurement of lattice spacing. This is the method of simultaneously measuring the same displacement with an X-ray interferometer and a light wave interferometer, and doing the absolute measurement of the lattice spacing of crystals with light wavelength. Avogadro constant is the constant that becomes the foundation of chemistry, and its relation with other basic constants is shown. The principle of X-ray interferometers is explained. As the elementary technologies for the absolute measurement of lattice spacing, the adjustment of X-ray interferometers, parallel movement table and angular adjustment table, light wave interferometer and the prevention of vibration and temperature change are described. The example of the measurement is reported. In order to improve the accuracy, the improvement of the equipment and the measurement in vacuum are prepared at present. (K.I.)

1994-04-01

174

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 "2"3"5U and "2"3"8U fission chambers and "3He proportional counters in JT-60 Upgrade. The in situ calibration was performed by moving the "2"5"2Cf neutron source toroidally through the JT-60 vacuum vessel. Detection efficiencies of three "2"3"5U 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)

1991-01-01

175

Measurement of absolute Al concentration in Al_xGa_1_-_xAs  

International Nuclear Information System (INIS)

A technique has been developed to measure the absolute Al concentration x in Al_xGa_1_-_xAs. The technique involves simultaneous measurements of the "2"7Al(p,?)"2"8Si 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.)

1987-04-01

176

Absolute measurement of the nitrogen fluorescence yield in air between 300 and 430 nm  

CERN Document Server

The nitrogen fluorescence induced in air is used to detect ultra-high energy cosmic rays and to measure their energy. The precise knowledge of the absolute fluorescence yield is the key quantity to improve the accuracy on the cosmic ray energy. The total yield has been measured in dry air using a 90Sr source and a [300-430 nm] filter. The fluorescence yield in air is 4.23 $\\pm$ 0.20 photons per meter when normalized to 760 mmHg, 15 degrees C and with an electron energy of 0.85 MeV. This result is consistent with previous experiments made at various energies, but with an accuracy improved by a factor of about 3. For the first time, the absolute continuous spectrum of nitrogen excited by 90Sr electrons has also been measured with a spectrometer. Details of this experiment are given in one of the author's PhD thesis [32].

Lefeuvre, G; Gorodetzky, P; Patzak, T; Salin, P

2007-01-01

177

Measuring the absolute DT neutron yield using the Magnetic Recoil Spectrometer at OMEGA and the NIF  

Energy Technology Data Exchange (ETDEWEB)

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 (ICF) 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.

Mackinnon, A; Casey, D; Frenje, J A; Johnson, M G; Seguin, F H; Li, C K; Petrasso, R D; Glebov, V Y; Katz, J; Knauer, J; Meyerhofer, D; Sangster, T; Bionta, R; Bleuel, D; Hachett, S P; Hartouni, E; Lepape, S; Mckernan, M; Moran, M; Yeamans, C

2012-05-03

178

Measurement of gamma radioactivity at moving vehicles  

International Nuclear Information System (INIS)

If vehicles shall be monitored when entering or existing nuclear sites or if trucks loaded with scrap steel shall be monitored for radioactivity a number of problems arise: geometrical effects, self absorption by the truck load, background influenced by the vehicle. Based on large area plastic scintillation detectors and a computer with an optimized algorithm, a modern vehicle monitor has been designed. It is an optimum means for monitoring moving vehicles for radioactivity. (orig.)

1994-05-24

179

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

Directory of Open Access Journals (Sweden)

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.

Ciro Del Negro

2011-12-01

180

Temperature-dependent absolute refractive index measurements of synthetic fused silica  

Science.gov (United States)

Using the Cryogenic, High-Accuracy Refraction Measuring System (CHARMS) at NASA's Goddard Space Flight Center, we have measured the absolute refractive index of five specimens taken from a very large boule of Corning 7980 fused silica from temperatures ranging from 30 to 310 K at wavelengths from 0.4 to 2.6 microns with an absolute uncertainty of +/-1 ×10-5. Statistical variations in derived values of the thermo-optic coefficient (dn/dT) are at the +/-2 × 10-8/K level. Graphical and tabulated data for absolute refractive index, dispersion, and thermo-optic coefficient are presented for selected wavelengths and temperatures along with estimates of uncertainty in index. Coefficients for temperature-dependent Sellmeier fits of measured refractive index are also presented to allow accurate interpolation of index to other wavelengths and temperatures. We compare our results to those from an independent investigation (which used an interferometric technique for measuring index changes as a function of temperature) whose samples were prepared from the same slugs of material from which our prisms were prepared in support of the Kepler mission. We also compare our results with sparse cryogenic index data from measurements of this material from the literature.

Leviton, Douglas B.; Frey, Bradley J.

2006-07-01

 
 
 
 
181

Temperature-dependent Absolute Refractive Index Measurements of Synthetic Fused Silica  

Science.gov (United States)

Using the Cryogenic, High-Accuracy Refraction Measuring System (CHARMS) at NASA's Goddard Space Flight Center, we have measured the absolute refractive index of five specimens taken from a very large boule of Corning 7980 fused silica from temperatures ranging from 30 to 310 K at wavelengths from 0.4 to 2.6 microns with an absolute uncertainty of plus or minus 1 x 10 (exp -5). Statistical variations in derived values of the thermo-optic coefficient (dn/dT) are at the plus or minus 2 x 10 (exp -8)/K level. Graphical and tabulated data for absolute refractive index, dispersion, and thermo-optic coefficient are presented for selected wavelengths and temperatures along with estimates of uncertainty in index. Coefficients for temperature-dependent Sellmeier fits of measured refractive index are also presented to allow accurate interpolation of index to other wavelengths and temperatures. We compare our results to those from an independent investigation (which used an interferometric technique for measuring index changes as a function of temperature) whose samples were prepared from the same slugs of material from which our prisms were prepared in support of the Kepler mission. We also compare our results with sparse cryogenic index data from measurements of this material from the literature.

Leviton, Douglas B.; Frey, Bradley J.

2006-01-01

182

Radioactivity concentration measuring device for radiation waste containing vessel  

International Nuclear Information System (INIS)

The device of the present invention can precisely and accurately measure a radioactive concentration of radioactive wastes irrespective of the radioactivity concentration distribution. Namely, a Ge detector having a collimator and a plurality of radiation detectors are placed at the outside of the radioactive waste containing vessel in such a way that it can rotate and move vertically relative to the vessel. The plurality of radiation detectors detect radiation coefficient signals at an assumed segment unit of a predetermined length in vertical direction and for every predetermined angle unit in the rotational direction. A weight measuring device determines the weight of the vessel. A computer calculates an average density of radioactivity for the region filled with radioactivity based on the determined net weight and radiation coefficient signals assuming that the volume of the radioactivity is constant. In addition, the computer calculates the amount of radioactivity in the assumed segment by conducting ? -ray absorption compensation calculation for the material in the vessel. Each of the amount of radioactivity is integrated to determine the amount of radioactivity in the vessel. (I.S.)

1993-03-04

183

System for absolute measurement of electrolytic conductivity in aqueous solutions based on van der Pauw's theory  

Science.gov (United States)

Based on an innovative application of van der Pauw's theory, a system was developed for the absolute measurement of electrolytic conductivity in aqueous solutions. An electrolytic conductivity meter was designed that uses a four-electrode system with an axial–radial two-dimensional adjustment structure coupled to an ac voltage excitation source and signal collecting circuit. The measurement accuracy, resolution and repeatability of the measurement system were examined through a series of experiments. Moreover, the measurement system and a high-precision electrolytic conductivity meter were compared using some actual water samples.

Zhang, Bing; Lin, Zhen; Zhang, Xiao; Yu, Xiang; Wei, Jiali; Wang, Xiaoping

2014-05-01

184

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

International Nuclear Information System (INIS)

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.

2011-03-20

185

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

Science.gov (United States)

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

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

2011-03-20

186

Temperature-dependent absolute refractive index measurements of synthetic fused silica  

CERN Document Server

Using the Cryogenic, High-Accuracy Refraction Measuring System (CHARMS) at NASA's Goddard Space Flight Center, we have measured the absolute refractive index of five specimens taken from a very large boule of Corning 7980 fused silica from temperatures ranging from 30 to 310 K at wavelengths from 0.4 to 2.6 microns with an absolute uncertainty of +/-1 x 10^-5. Statistical variations in derived values of the thermo-optic coefficient (dn/dT) are at the +/-2 x 10^-8/K level. Graphical and tabulated data for absolute refractive index, dispersion, and thermo-optic coefficient are presented for selected wavelengths and temperatures along with estimates of uncertainty in index. Coefficients for temperature-dependent Sellmeier fits of measured refractive index are also presented to allow accurate interpolation of index to other wavelengths and temperatures. We compare our results to those from an independent investigation (which used an interferometric technique for measuring index changes as a function of temperatur...

Leviton, Douglas B

2008-01-01

187

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

Directory of Open Access Journals (Sweden)

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.

Ruiz P. D.

2010-06-01

188

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

2010-07-01

189

Chiral isothiocyanates - An approach to determination of the absolute configuration using circular dichroism measurement  

Science.gov (United States)

Chiral alkyl 2-isothiocyanates have been obtained from enantiopure, aliphatic amines. ECD measurements allowed us to correlate an absolute configuration at C-2 with a sign of the Cotton effect (CE) observed for n-?* transition at the longer-wavelength range of the spectrum. Chirooptical data calculated for all enantiomers were consistent with the measured CE values and indicated that the weak absorption band at 240 nm could give an important information concerning the stereochemistry of simple, chiral isothiocyanates. Optically active esters of 2-isothiocyanatocarboxylic acids, prepared from ?-amino acids, showed two absorption bands located over 195 nm. The more intensive band near 200 nm and the weak absorption located at 250 nm were related to n-?* transitions in NCS group. TD DFT calculations carried out for methyl esters of 2-isothiocyanatocarboxylic acids showed the correlation between signs of CE determined for both absorption bands, and the absolute configuration on C-2.

Michalski, Oskar; Cie?, Dariusz

2013-04-01

190

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

1983-01-01

191

Absolute measurements of electron capture cross sections of C3+ from atomic and molecular hydrogen  

International Nuclear Information System (INIS)

Absolute measurements of single- and double-electron-capture cross sections by C3+ projectiles on atomic and molecular hydrogen targets were performed for projectile energies between 1.0 and 3.5 MeV for the single- and 1.0 and 2.0 MeV for the double-capture processes. The ?H/?H2 cross section ratios were measured using an absolutely calibrated tungsten-tube furnace for the production of atomic hydrogen. The single-capture data are compared with calculations based on the boundary-corrected first Born approximation, the eikonal approximation and a semiclassical model, presenting a good overall agreement. Calculations for the double capture using an analytical expression, obtained within the independent electron approximation and based on the same semiclassical model, give a reasonable qualitative description of the data. (author)

2000-02-14

192

Average value of available measurements of the absolute air-fluorescence yield  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The air-fluorescence yield is a key parameter for determining the energy scale of ultra-high-energy cosmic rays detected by fluorescence telescopes. A compilation of the available measurements of the absolute air-fluorescence yield normalized to its value in photons per MeV for the 337 nm band at given pressure and temperature has been recently presented in Ref. [1]. Also, in that paper, some corrections in the evaluation of the energy deposited in the corresponding experime...

Rosado, J.; Blanco, F.; Arqueros, F.

2011-01-01

193

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

CERN Document Server

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.

Nagornyi, V D

2014-01-01

194

Absolute frequency measurement of rubidium 5S-7S two-photon transitions.  

Science.gov (United States)

We report the absolute frequency measurements of rubidium 5S-7S two-photon transitions with a cw laser digitally locked to an atomic transition and referenced to an optical frequency comb. The narrow, two-photon transition, 5S-7S (760 nm), insensitive to first-order in a magnetic field, is a promising candidate for frequency reference. The performed tests yielded more accurate transition frequencies than previously reported. PMID:24322079

Morzy?ski, Piotr; Wcis?o, Piotr; Ablewski, Piotr; Gartman, Rafa?; Gawlik, Wojciech; Mas?owski, Piotr; Nagórny, Bart?omiej; Ozimek, Filip; Radzewicz, Czes?aw; Witkowski, Marcin; Ciury?o, Roman; Zawada, Micha?

2013-11-15

195

High-accuracy absolute distance measurement using frequency comb referenced multiwavelength source  

International Nuclear Information System (INIS)

We propose a new approach to multiple-wavelength interferometry, targeted to high bandwidth absolute distance measurement, with nanometer accuracy over long distances. Two cw lasers are stabilized over a wide range of frequency intervals defined by an optical frequency comb, thus offering an unprecedented large choice of synthetic wavelengths. By applying a superheterodyne detection technique, we demonstrated experimentally an accuracy of 8 nm over 800 mm for target velocities up to 50 mm/s

2008-05-10

196

Absolute Frequency Measurement of Rubidium 5S-7S Two-Photon Transitions  

CERN Document Server

We report the absolute frequency measurements of rubidium 5S-7S two-photon transitions with a cw laser digitally locked to an atomic transition and referenced to an optical frequency comb. The narrow, two-photon transition, 5S-7S (760 nm) insensitive to first order in a magnetic field, is a promising candidate for frequency reference. The performed tests yield the transition frequency with accuracy better than reported previously.

Morzynski, Piotr; Ablewski, Piotr; Gartman, Rafal; Gawlik, Wojciech; Maslowski, Piotr; Nagorny, Bartlomiej; Ozimek, Filip; Radzewicz, Czeslaw; Witkowski, Marcin; Ciurylo, Roman; Zawada, Michal

2013-01-01

197

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

International Nuclear Information System (INIS)

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.

2010-09-13

198

Calibration of a Shack-Hartmann sensor for absolute measurements of wavefronts  

International Nuclear Information System (INIS)

We demonstrate a method with which to calibrate a Shack-Hartmann sensor for absolute wavefront measurement of collimated laser beams. Nearly perfect spherical wavefronts originating from a single-mode fiber were used as references. After the calibration, the uncertainty of the wavefront was less than ?/100 peak to valley across a diameter of 6mm. For example, this method allowed us to balance aberrations and prepare collimated beams with wavefronts that are plane to ?/500 across 1mm

2005-10-20

199

Comment on 'Simultaneous gravity and gradient measurements from a recoil-compensated absolute gravimeter'  

CERN Multimedia

The article (Niebauer et al. 2011 Metrologia 48 154-163) reports on the important innovations enhancing the ability of absolute gravimeter to measure vertical gravity gradient along with the gravity acceleration. This comment suggests experiments to further assess the improvements and the results obtained with the modified instrument, considers some limitations of non-linear models in metrology and ways to overcome them, and discusses possible applications of the described instrument.

Nagornyi, V D

2011-01-01

200

A comparison of blindpulling and blindwalking as measures of perceived absolute distance  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Blindwalking has become a common measure of perceived absolute distance and location, but it requires a relatively large testing space and cannot be used with people for whom walking is difficult or impossible. In the present article, we describe an alternative response type that is closely matched to blindwalking in several important respects but is less resource intensive. In the blindpulling technique, participants view a target, then close their eyes and pull a length of tape or rope betw...

Philbeck, John W.; Woods, Adam J.; Kontra, Carly; Zdenkova, Petra

2010-01-01

 
 
 
 
201

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)

2009-01-01

202

Relative Gravity Measurement Campaign during the 8th International Comparison of Absolute Gravimeters (2009)  

Science.gov (United States)

The 8th International Comparison of Absolute Gravimeters (ICAG-2009) and the associated Relative Gravity Campaign (RGC2009) took place at the Bureau International des Poids et Mesures (BIPM) between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters and 9 relative gravimeters participated in the ICAG/RGC campaign. Accurate absolute and relative gravity measurements as well as precision levelling measurements were performed on the micro-gravity 3D-grid at the BIPM. The 2009 comparison was the first to be organized as a Comité International des Poids et Mesures (CIPM) metrological Key Comparison under the CIPM MRA (Mutual Recognition Arrangement), which means that the result will be officially recognized by the governmental organizations responsible. As a consequence, the relative gravimeters employed were carefully selected and the measurement schedules were rigorously enforced compared with earlier campaigns. Thus the quality of the RGC2009 and the determination of the BIPM local gravity network were improved. After 30 years and eight successive ICAGs, the BIPM has decided to transfer its role to the national metrological institutes, although the CIPM will continue to organize the key comparison as ICAGs. The background to the RGC2009, and the organization, data processing and final results of the gravity and vertical gravity gradients, are presented in this paper. This report is more detailed than previous final reports of the RGCs.

Jiang, Z.; Pálinkáš, V.; Francis, O.; Jousset, P.; Mäkinen, J.; Merlet, S.; Becker, M.; Coulomb, A.; Kessler-Schulz, K. U.; Schulz, H. R.; Rothleitner, Ch; Tisserand, L.; Lequin, D.

2012-02-01

203

Absolute Measurement of Electron Cloud Density in aPositively-Charged Particle Beam  

Energy Technology Data Exchange (ETDEWEB)

Clouds of stray electrons are ubiquitous in particle accelerators and frequently limit the performance of storage rings. Earlier measurements of electron energy distribution and flux to the walls provided only a relative electron cloud density. We have measured electron accumulation using ions expelled by the beam. The ion energy distribution maps the depressed beam potential and gives the dynamic cloud density. Clearing electrode current reveals the static background cloud density, allowing the first absolute measurement of the time-dependent electron cloud density during the beam pulse.

Kireeff Covo, Michel; Molvik, Arthur W.; Friedman, Alex; Vay,Jean-Luc; Seidl, Peter A.; Logan, Grant; Baca, David; Vujic, Jasmina L.

2006-04-27

204

Absolute Measurement of Electron Cloud Density in a Positively-Charged Particle Beam  

Energy Technology Data Exchange (ETDEWEB)

Clouds of stray electrons are ubiquitous in particle accelerators and frequently limit the performance of storage rings. Earlier measurements of electron energy distribution and flux to the walls provided only a relative electron cloud density. We have measured electron accumulation using ions expelled by the beam. The ion energy distribution maps the depressed beam potential and gives the dynamic cloud density. Clearing electrode current reveals the static background cloud density, allowing the first absolute measurement of the time-dependent electron cloud density during the beam pulse.

Covo, M K; Molvik, A W; Friedman, A; Vay, J; Seidl, P A; Logan, B G; Baca, D; Vujic, J L

2006-05-18

205

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

CERN Multimedia

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.

Barschel, C

2013-01-01

206

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

CERN Document Server

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.

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

207

Radioactivity. Fundamentals, measurement, applications. 4. rev. and enl. ed.; Radioaktivitaet. Grundlagen - Messungen - Anwendungen  

Energy Technology Data Exchange (ETDEWEB)

The following topics are dealt with: Properties of the atomic nucleus, radioactive nucleus transmutations, natural and artificial nuclides, production of radioactive nuclides, radioactive radiation sources, interaction and measurement of ionizing radiation, applications of radioactive nuclides, radiation protection. (HSI)

Stolz, W. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Angewandte Physik

2003-02-01

208

Towards absolute activity measurements by ionisation chambers using the PENELOPE Monte-Carlo code  

International Nuclear Information System (INIS)

The Monte-Carlo code PENELOPE for Ionisation Chamber Simulation Method has been applied for the calculation of ionisation-chamber (IC) calibration factors. Measuring only a few radionuclides well selected within the relevant energy range, and determining an adjustable parameter, commonly used radionuclides can be measured without any specific calibration. The simulation revealed a discontinuity in the IC response as a function of photon energy and its dependence on the chemical composition of the radioactive solution

2003-10-01

209

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

Directory of Open Access Journals (Sweden)

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.

Jen-Chia Tsai

2006-04-01

210

Spatially Resolved, Absolutely Calibrated Soft X-ray Measurements at the Nike Laser Facility  

Science.gov (United States)

The Laser Plasma Branch at the Naval Research Laboratory has an ongoing program to extend and benchmark the atomic physics packages (SCROLL, HULLAC, MIX,..) needed for the radiation-hydrodynamics simulations used to design targets for inertial confinement fusion. Previously, good agreement in absolute spectral intensity was achieved between experimental results and the output of Virtual Spectro, a post-processor for detailed treatment of atomic physics and radiation transport including non-LTE conditions. These initial comparisons were limited to a single line of sight. More recently, absolutely calibrated measurements of soft x-rays (0.5-10 nm) have been made with 1D spatial resolution (dx ˜0.1 mm), spectral resolution (E/dE ˜10-30), and time resolution (t ˜0.3 ns). This poster will present results for a variety of materials and laser conditions with comparison to the results of Virtual Spectro.

Feldman, U.; Klapisch, M.; Busquet, M.; Weaver, J. L.; Seely, J.; Colombant, D.; Mostovych, A.; Back, C. A.; Constantin, C.; Holland, G.; Fielding, D.

2004-11-01

211

Silicon microcantilevers with different actuation-readout schemes for absolute pressure measurement  

International Nuclear Information System (INIS)

Silicon resonant microcantilevers for the measurement of the absolute pressure have been fabricated through micromachining processes. The first release is based on vertical resonant actuation and detection, both externally implemented, respectively through a piezoelectric actuator and an optical lever. The variation in resonance response was investigated as a function of pressure (10-1 to 105 Pa), both in terms of resonance frequency and quality factor. We demonstrated the feasibility of a miniaturized absolute pressure sensor working over a six decades range. The second release is based on lateral resonating microcantilevers in which a significative upgrade is represented by the miniaturization and integration of the actuator and the sensing directly on chip providing a more compact and potentially interesting solution for industrial vacuum applications. Actuation is performed with an electrostatic modulated force, while detection relies on a capacitive readout. Preliminary experiments are encouraging for the replication of the results obtained with the first version

2008-03-01

212

Glacial mass balance determination in the accumulation zone by in situ measurements of Chernobyl radioactivity  

International Nuclear Information System (INIS)

Radioactive fallout from atmospheric thermo-nuclear tests conducted in 1954 and 1962-1963, and more recently from the Chernobyl accident on 26 April 1986, provide markers, or well-known levels, in the snow layers of the north hemisphere glacier accumulation zones. The design and operation of the in situ measurement of gamma rays from cesium-137 (662 KeV) in ice bore-holes allows rapid detection in the field of the Chernobyl radioactive layer of snow. The validity of this detection method is much enhanced due to the 29.5 year half-life of cesium-137. These measurements indicate the absolute dating of snow layers deposited since May 1986; they give the spatio-temporal variations of glacial mass balance, as well as fallout amounts of radio-isotopes

1986-04-26

213

Measurements of absolute gamma-ray emission probabilities in the decay of {sup 233}Pa  

Energy Technology Data Exchange (ETDEWEB)

Gamma-ray emission probabilities from the {beta}{sup -} decay of {sup 233}Pa were measured with planar (LEPS) and coaxial Ge detectors. A {sup 233}Pa source was produced after radiochemical separation from a {sup 237}Np sample in which the parent ({sup 237}Np) and daughter ({sup 233}Pa) nuclides were in secular equilibrium. Absolute {gamma}-ray emission probabilities per 100 {alpha} decays of the parent nuclide {sup 237}Np were also measured in conjunction with the {alpha}- and {gamma}-ray spectroscopy techniques.

Kondev, F.G., E-mail: kondev@anl.gov [Argonne National Laboratory, Argonne, IL 60439 (United States); Ahmad, I.; Greene, J.P. [Argonne National Laboratory, Argonne, IL 60439 (United States); Nichols, A.L. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Kellett, M.A. [Department of Nuclear Science and Applications, Nuclear Data Section, International Atomic Energy Agency, A-1400 Vienna (Austria)

2011-10-01

214

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1990-01-01

215

Measurement of the Absolute Raman Cross Section of the Optical Phonons in Type Ia Natural Diamond  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The absolute Raman cross section \\(\\sigma_{RS}\\)of the first-order \\(1332-cm^{?1}\\) optical phonons in type Ia natural diamond was measured using 785- and 1064-nm pump lasers for the excitation of Raman scattering. A small temperature-controlled blackbody was used for the signal calibration of the 785- and 1064-nm Raman systems. Measurements were made with a 0.9-mm thick (111) natural diamond sample. Values of \\(2.7\\pm0.6×10^{?29}\\) and \\(0.95\\pm0.2×10^{?29} cm^2\\) per carbon atom wer...

2012-01-01

216

Measurement of the speed-of-light perturbation of free-fall absolute gravimeters  

Science.gov (United States)

We report on a direct measurement of the relativistic Doppler shift with a commercial free-fall absolute gravimeter of the type FG5X. The observed Doppler shift, which is commonly called speed-of-light perturbation, can be well described by the relativistic Doppler formula, where the constant object velocity is replaced by a time-dependent velocity with constant acceleration. The observed speed-of-light perturbation stands in contrast to other publications, which predict a higher frequency shift. It has been measured with a relative uncertainty of 1.1 × 10?3.

Rothleitner, Ch; Niebauer, T. M.; Francis, O.

2014-06-01

217

Absolute Soft X-ray Emission Measurements at the Nike Laser  

Science.gov (United States)

Recent experiments at the Nike laser facility have demonstrated that, when a low intensity prepulse ( 2main laser intensity) is used to heat a thin Au or Pd coating on a planar CH target, the growth of non-uniformities due to laser imprint can be reduced from the growth observed for an uncoated CH target. The absolute radiation intensity in the soft x-ray region (0.1-1 keV) has a important role in the energy balance for layered targets. There is an ongoing effort to characterize the soft x-ray emission using an absolutely calibrated transmission grating spectrometer and filtered diode modules. Measurements of the angular distribution of the emission from unlayered solid targets (Au, Pd, CH) have recently been made using an array of moveable filtered diode modules. The data from the angular distribution studies will be presented. A new absolutely calibrated, time-resolving transmission grating spectrometer has been installed at the Nike. The new version has improved spectral resolution, selectable transmission filters, and the potential for simultaneous temporal, spatial, and spectral resolution. Preliminary data from the new spectrometer will be presented and future experiments will be briefly discussed. *Work was supported by DoE

Weaver, J.; Atkin, R.; Boyer, C.; Colombant, D.; Feldman, U.; Fielding, D.; Gardner, J.; Holland, G.; Klapisch, M.; Mostovych, A. N.; Obenscain, S.; Seely, J. F.

2002-11-01

218

Absolute reliability of isokinetic knee flexion and extension measurements adopting a prone position.  

Science.gov (United States)

The main purpose of this study was to determine the absolute and relative reliability of isokinetic peak torque (PT), angle of peak torque (APT), average power (PW) and total work (TW) for knee flexion and extension during concentric and eccentric actions measured in a prone position at 60, 180 and 240° s(-1). A total of 50 recreational athletes completed the study. PT, APT, PW and TW for concentric and eccentric knee extension and flexion were recorded at three different angular velocities (60, 180 and 240° s(-1)) on three different occasions with a 72- to 96-h rest interval between consecutive testing sessions. Absolute reliability was examined through typical percentage error (CV(TE)), percentage change in the mean (ChM) and relative reliability with intraclass correlations (ICC(3,1)). For both the knee extensor and flexor muscle groups, all strength data (except APT during knee flexion movements) demonstrated moderate absolute reliability (ChM 0·70; and CV(TE) knee movement (flexion and extension), type of muscle action (concentric and eccentric) and angular velocity (60, 180 and 240° s(-1)). Therefore, the current study suggests that the CV(TE) values reported for PT (8-20%), APT (8-18%) (only during knee extension movements), PW (14-20%) and TW (12-28%) may be acceptable to detect the large changes usually observed after rehabilitation programmes, but not acceptable to examine the effect of preventative training programmes in healthy individuals. PMID:23216765

Ayala, F; De Ste Croix, M; Sainz de Baranda, P; Santonja, F

2013-01-01

219

Radioactivity measurements for the ERMES project at the STELLA facility  

Directory of Open Access Journals (Sweden)

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.

Gallese B.

2012-04-01

220

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

Science.gov (United States)

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.

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

2012-01-01

 
 
 
 
221

Measurement of metallothionein by radioactive silver saturation method  

International Nuclear Information System (INIS)

Radioactive silver saturation method has been developed for measurement of metallothionein in tissues of animal. The results show that the relative affinities of metals for metallothionein in 0.5M glycine buffer at pH 8.5 is Ag+ > Cu2+ > Cd2+ > Hg2+ > Zn2+, and measurement of metallothionein in liver of rats induced by zinc using radioactive silver satruation method is sensitive and valid

1990-01-01

222

Innovative non-invasive method for absolute intracranial pressure measurement without calibration.  

Science.gov (United States)

A new absolute ICP (aICP) measurement method was designed which does not need calibration. In this study we compared a new method with invasive aICP method in ICU on the patients with closed severe traumatic brain injury. A new method is based on two-depth TCD technique for aICP and external absolute pressure aPe comparison using the eye artery (EA) as natural "balance". The intracranial segment of EA is compressed by aICP and the extracranial segment is compressed by aPe applied to the tissues surrounding the eye. The blood flow parameters in both EA segments are approximately the same when aPe = aICP. Two-depth TCD device is used as an indicator of balance aPe = aICP when the pulsatility index of blood flow velocity waveform in intracranial and extracranial segments are the same. Fifty seven simultaneous invasive and non-invasive aICP measurements were performed in aICP range from 3.0 to 37.0 mmHg. Bland Altman plot of the differences between simultaneous invasive and non-invasive aICP measurements shows the negligible mean difference (mean = 0.94 mmHg) with a standard deviation of 6.18 mmHg. This validation study shows that it is possible to measure aICP non-invasively without calibration of the system with 95% confidence interval of 12 mmHg. PMID:16463881

Ragauskas, A; Daubaris, G; Dziugys, A; Azelis, V; Gedrimas, V

2005-01-01

223

Absolute radiant power measurement of the X-ray free-electron laser at SACLA  

International Nuclear Information System (INIS)

The Japanese hard X-ray free-electron laser (XFEL), SACLA (SPring-8 Angstrom Compact free-electron LAser), reached laser amplification at 10 keV photon energy in June 2011. SACLA can provide XFELs with its wavelength of shorter than 0.1 nm. Since the radiant power is a fundamental parameter of the XFEL beam which strongly influences nonlinear effects, its measurement in absolute terms is of significant importance. In the present study, the absolute radiant power of the XFEL was measured using a cryogenic radiometer at the BL3 in SACLA. The radiant power as a function of a silicon attenuator thickness was also measured to estimate the contribution of the higher harmonics. The radiant power in the range between 8 ?W and 1005 ?W was measured in the photon energies of 4.4 keV, 5.8 keV, 9.6 keV, 13.6 keV and 16.8 keV. The contribution of the higher harmonics is negligible except for the photon energy of 4.4 keV. The third harmonics component in the photon energy of 4.4 keV is about 1 %.

2013-03-22

224

Absolute radiant power measurement of the X-ray free-electron laser at SACLA  

Science.gov (United States)

The Japanese hard X-ray free-electron laser (XFEL), SACLA (SPring-8 Angstrom Compact free-electron LAser), reached laser amplification at 10 keV photon energy in June 2011. SACLA can provide XFELs with its wavelength of shorter than 0.1 nm. Since the radiant power is a fundamental parameter of the XFEL beam which strongly influences nonlinear effects, its measurement in absolute terms is of significant importance. In the present study, the absolute radiant power of the XFEL was measured using a cryogenic radiometer at the BL3 in SACLA. The radiant power as a function of a silicon attenuator thickness was also measured to estimate the contribution of the higher harmonics. The radiant power in the range between 8 ?W and 1005 ?W was measured in the photon energies of 4.4 keV, 5.8 keV, 9.6 keV, 13.6 keV and 16.8 keV. The contribution of the higher harmonics is negligible except for the photon energy of 4.4 keV. The third harmonics component in the photon energy of 4.4 keV is about 1 %.

Tanaka, Takahiro; Kato, Masahiro; Kurosawa, Tadahiro; Saito, Norio; Kudo, Togo; Tono, Kensuke; Yabashi, Makina; Ishikawa, Tetsuya

2013-03-01

225

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

1976-08-23

226

Absolute beam flux measurement at NDCX-I using gold-melting calorimetry technique  

Energy Technology Data Exchange (ETDEWEB)

We report on an alternative way to measure the absolute beam flux at the NDCX-I, LBNL linear accelerator. Up to date, the beam flux is determined from the analysis of the beam-induced optical emission from a ceramic scintilator (Al-Si). The new approach is based on calorimetric technique, where energy flux is deduced from the melting dynamics of a gold foil. We estimate an average 260 kW/cm2 beam flux over 5 {micro}s, which is consistent with values provided by the other methods. Described technique can be applied to various ion species and energies.

Ni, P.A.; Bieniosek, F.M.; Lidia, S.M.; Welch, J.

2011-04-01

227

The cerebral blood flow measurement without absolute input function value for PET O-15 injection method  

International Nuclear Information System (INIS)

This paper shows the method of the measurement for the region of interest's (ROI's) cerebral blood flow (CBF) using PET data and the input function without the absolute density value of the radio activity. The value of the input function and the output function are fixed from the clinical data by regression analysis. The input function and the output function are transformed by the Fourier transform. The transfer function of the differential equation of the compartment model is got by these Fourier transforms. The CBF can be estimated by the transfer function regression analysis. Results are compared between the proposal and conventional methods. (author)

2004-01-01

228

Measurement of the absolute branching fraction of D0-->K-pi+.  

Science.gov (United States)

We measure the absolute branching fraction for D(0)-->K(-)pi(+) using partial reconstruction of B(0)-->D(*+)Xl(-)nu(l) decays, in which only the charged lepton and the pion from the decay D(*+)-->D(0)pi(+) are used. Based on a data sample of 230 x 10(6) BB pairs collected at the Upsilon(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, we obtain B(D(0)-->K(-)pi(+)) = (4.007+/-0.037+/-0.072)%, where the first uncertainty is statistical and the second is systematic. PMID:18352359

Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Eigen, G; Ofte, I; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Tackmann, K; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Williams, D C; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Fisher, P H; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F

2008-02-01

229

Measurements of the absolute branching fractions of B+/- --> K+/-X(cc).  

Science.gov (United States)

We study the two-body decays of B+/- mesons to K+/- and a charmonium state X(cc) in a sample of 210.5 fb(-1) of data from the BABAR experiment. We perform measurements of absolute branching fractions beta(B+/- --> K+/-X(cc)) using a missing mass technique, and report several new or improved results. In particular, the upper limit beta(B+/- --> K+/- X(3872)) 4.2% will help in understanding the nature of the recently discovered X(3872). PMID:16486923

Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Pappagallo, M; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Teodorescu, L; Blinov, A E; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Minamora, J S; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Andreassen, R; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Altenburg, D; Feltresi, E; Hauke, A; Spaan, B; Brandt, T; Brose, J; Dickopp, M; Klose, V; Lacker, H M; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Wu, J; Dubitzky, R S; Langenegger, U; Marks, J; Schenk, S; Uwer, U; Schott, G; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Gaillard, J R; Nash, J A; Nikolich, M B; Vazquez, W Panduro; Chai, X; Charles, M J; Mader, W F; Mallik, U; Mohapatra, A K; Ziegler, V; Cochran, J; Crawley, H B; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Petersen, T C; Plaszczynski, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Parry, R J; Payne, D J; Schofield, K C; Touramanis, C; Cormack, C M; Di Lodovico, F; Menges, W; Sacco, R; Brown, C L; Cowan, G; Flaecher, H U; Green, M G; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Edgar, C L; Hodgkinson, M C; Kelly, M P; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Li, X; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Viaud, B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Pulliam, T

2006-02-10

230

Calibration of a Shack-Hartmann sensor for absolute measurements of wavefronts.  

Science.gov (United States)

We demonstrate a method with which to calibrate a Shack-Hartmann sensor for absolute wavefront measurement of collimated laser beams. Nearly perfect spherical wavefronts originating from a single-mode fiber were used as references. After the calibration, the uncertainty of the wavefront was less than lambda/100 peak to valley across a diameter of 6 mm. For example, this method allowed us to balance aberrations and prepare collimated beams with wavefronts that are plane to lambda/500 across 1 mm. PMID:16252653

Chernyshov, Alexander; Sterr, Uwe; Riehle, Fritz; Helmcke, Jürgen; Pfund, Johannes

2005-10-20

231

Absolute Measurement of Hadronic Branching Fractions of the D_s^+ Meson  

CERN Multimedia

The branching fractions of D_s meson decays serve to normalize many measurements of processes involving charm quarks. Using 298 /pb 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.

Alexander, J; 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 G; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; López, A; Méndez, H; Ramírez, 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

2008-01-01

232

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)

1962-01-01

233

Recent improvements of ISOLTRAP Absolute mass measurements of exotic nuclides at $10^{-8}$ precision  

CERN Document Server

In the past three years, the sensitivity and the performance of the Penning trap mass spectrometer ISOLTRAP have been enhanced significantly. These improvements, which range from technical developments to systematic studies of the various factors contributing to the uncertainty of the final mass result, now allow mass measurements of short-lived radionuclides with half-lives of less than 100 ms and with a precision of better than 10^-8. Using a newly developed carbon cluster ion source, ISOLTRAP can perform absolute mass measurements relative to the microscopic mass standard ^12C. These developments are reviewed as pertaining to the extension of ISOLTRAP mass measurements to higher precision and shorter half-lives and to molecular mass measurements. PACS: 07.75.+h (Mass spectrometers and related techniques), 21.10.Dr (Binding energies and masses), 32.10.Bi (Atomic masses, mass spectra, abundances, and isotopes), 36.40.Wa (Charged clusters).

Kellerbauer, A G

2003-01-01

234

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

CERN Multimedia

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.

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

235

Absolute phase measurement with extrinsic Fabry-Perot optical fiber sensors  

Science.gov (United States)

This paper describes the use of the first and second optical return paths in a moderate to high finesse Fabry-Perot sensor to measure the absolute phase in extrinsic Fabry- Perot interferometric (EFPI) sensors. Path-matched differential interferometry (PMDI) using high finesse EFPI sensors, a low finesse Fabry-Perot read-out interferometer, and a broadband light source consisting of amplified spontaneous emission (ASE) from an erbium-doped fiber amplifier (EDFA) is used to illustrate the idea. The first and second multiple paths in the Fabry-Perot read-out sensor are used to provide two distinct path-match conditions from the same scanning Fabry-Perot read-out interferometer. The difference in fringe numbers between the centers of two orders of interference fringe packets formed by the distinct path-match conditions makes possible a simple method of measuring the cavity length of EFPI sensors, which in turn can be used to measure absolute phase and the corresponding strain. Sensor cavity length measurement using the multiple return paths in the high finesse Fabry-Perot sensor is compared with measurements made using the modulation transfer function found using an optical spectrum analyzer. Then the multiple return path technique is then used to make strain measurements on a cantilever beam. Comparisons with resistance strain gate measurements are favorable. Characterization tests indicate that the proposed technique has a cavity length measurement resolution on the order of 1.1. micrometer, which translates to a strain resolution of 28 (mu) (epsilon) for a 4 cm gage length sensor.

Chang, Chia-Chen; Sirkis, James S.

1996-10-01

236

Absolute measurement of the nitrogen fluorescence yield in air between 300 and 430 nm  

International Nuclear Information System (INIS)

The nitrogen fluorescence induced in air is used to detect ultra-high-energy cosmic rays (UHECR) and to measure their energy. The precise knowledge of the absolute fluorescence yield is the key quantity to improve the accuracy on the cosmic ray energy. The total yield has been measured in dry air using a 90Sr source and a [300-430 nm] filter. The fluorescence yield in air is 4.23±0.21 photons/m when normalized to 760 mmHg, 15 oC and with an electron energy of 0.85 MeV. This result is consistent with previous experiments made at various energies, but with an accuracy improved by a factor of about 3. For the first time, the absolute continuous spectrum of nitrogen excited by 90Sr electrons has also been measured with a spectrometer. Details of this experiment are given in one of the author's Ph. D. thesis [G. Lefeuvre, Ph. D. Thesis, Paris 7 University, 2006 (Ref: APC-26-06) .

2007-07-21

237

Measurements of radioactive dusts in high altitude air  

International Nuclear Information System (INIS)

The radioactivities of airborne dust in samples were measured. The samples had been collected at high altitude by the Japan Air Self-Defense Force from April 2003 to March 2004. The data were obtained for the gross beta activity, gamma nuclide determination and radiochemical analysis. It is shown that there is no appreciable difference between the activity levels of this time and ones of the year before. Seasonal variations are little pronounced. The radioactivity is stable in the low level at high altitude. Radioactive gas (gaseous radiodine) was not detected. (author)

2004-08-01

238

Measurements of radioactive dusts in high altitude air  

International Nuclear Information System (INIS)

The radioactivities of airborne dust in samples were measured. The samples had been collected at high altitude by the Japan Air Self-Defense Force from April 2004 to March 2005. The data were obtained for the gross beta activity, gamma nuclide determination and radiochemical analysis. It is shown that there is no appreciable difference between the activity levels of this time and ones of the year before. Seasonal variations are little pronounced. It is found that the radioactivity have been stable in the low level at high altitude. Radioactive gas (gaseous radioiodine) was not detected. (author)

2005-07-01

239

Measurements of radioactive dusts in high altitude air  

International Nuclear Information System (INIS)

The radioactively of airborne dust in samples collected by aircraft of the Japan Air Self-Defense Force at high altitude during the period between April 2001 to March 2002 were measured. The data of the gross beta activity, gamma nuclide determination and radiochemical analysis show that there is no appreciable difference from the activity levels of the year before. Seasonal variations are becoming less pronounced and this shows that the low level radioactivity at high altitude is stable. Radioactive gas (gaseous radioiodine) was not detected. (author)

2003-09-01

240

Measurements of radioactive dusts in high altitude air  

International Nuclear Information System (INIS)

The radioactivities of airborne dust in samples were measured. The samples had been collected at high altitude by the Japan Air Self-Defense Force from April 2002 to March 2003. The data were obtained for the gross beta activity, gamma nuclide determination and radiochemical analysis. It is shown that there is no appreciable difference between the activity levels of this time and ones of the year before. Seasonal variations are little pronounced. The radioactivity is stable in the low level at high altitude. Radioactive gas (gaseous radioiodine) was not detected. (author)

2003-10-01

 
 
 
 
241

Absolutely referenced distance measurement by combination of time-of-flight and digital holographic methods  

Science.gov (United States)

We present a novel optical system for distance measurement based on the combination of optical time-of-flight metrology and digital holography. In addition absolute calibration of the measurement results is performed by a sideband modulation technique. For the time-of-flight technique a diode laser (1470 nm) is modulated sinusoidally (128 MHz). The light reflected and scattered by an object is detected by an avalanche-photo-diode. The phase difference between the sent and detected modulation is a measure for the distance between the sensor and the object. This allows for distance measurements up to 1.17 m with resolutions of ~2 mm. The interferometric setup uses 4 whispering-gallery-mode lasers to perform multiwavelengths-holographic distance measurements. The four wavelengths span the range from 1547 nm to 1554 nm. The unambiguous measurement measurement-range of the interferometric setup is approx. 7 mm while resolutions of 0.6 ?m are observed. Both setups are integrated into one setup and perform measurements synchronously. Exact knowledge of the frequency differences of hundreds of GHz between the four lasers is crucial for the interferometric fine scale measurement. For this aim the light of the lasers is phase-modulated with frequencies of 36 GHz and 40 GHz to produce optical sidebands of higher order, thus generating beat signals in the hundreds-of-MHz regime, which can be measured electronically. The setup shows a way to measure distances in the meter range with sub-micron resolution.

Fratz, Markus; Weimann, Claudius; Wölfelschneider, Harald; Koos, Christian; Höfler, Heinrich

2014-03-01

242

Present status of environmental radioactivity measurement and its problems  

International Nuclear Information System (INIS)

Various Measuring Methods of Environmental Radioactivity are reviewed with information on the recently established Japanese standard analytical methods of radioactive nuclides in the environment. The following topics are specially explained from the view point of applied physics with references to the papers published. (1) Cerenkov radiation measurements of ? ray emitters such as 90Sr (90Y) and 144Ce (144Pr). (2) Liquid scintillation measurements of ? ray emitters, including tritium in different chemical species. (3) Determination of ? ray emitters by their radiations after radiochemical purifications. (4) Mass spectrometric measurements (especially by ICP-MS) of long-lived nuclides. (author)

1991-01-01

243

ABSOLUTE MEASUREMENT OF THE POLARIZATION OF HIGH ENERGY PROTON BEAMS AT RHIC  

Energy Technology Data Exchange (ETDEWEB)

The spin physics program at the Relativistic Heavy Ion Collider (RHIC) requires knowledge of the beam polarization to better than 5%. Such a goal is made the more difficult by the lack of knowledge of the analyzing power of high energy nuclear physics processes. To overcome this, a polarized hydrogen jet target was constructed and installed at one intersection region in RHIC where it intersects both beams and utilizes the precise knowledge of the jet atomic hydrogen beam polarization to measure the analyzing power in proton-proton elastic scattering in the Nuclear Coulomb Interference (CNI) region at the prescribed RHIC proton beam energy. The reverse reaction is used to assess the absolute beam polarization. Simultaneous measurements taken with fast high statistics polarimeters that measure the p-Carbon elastic scattering process also in the CNI region use the jet results to calibrate the latter.

MAKDISI,Y.; BRAVAR, A. BUNCE, G. GILL, R.; HUANG, H.; ET AL.

2007-06-25

244

ABSOLUTE MEASUREMENT OF THE POLARIZATION OF HIGH ENERGY PROTON BEAMS AT RHIC  

International Nuclear Information System (INIS)

The spin physics program at the Relativistic Heavy Ion Collider (RHIC) requires knowledge of the beam polarization to better than 5%. Such a goal is made the more difficult by the lack of knowledge of the analyzing power of high energy nuclear physics processes. To overcome this, a polarized hydrogen jet target was constructed and installed at one intersection region in RHIC where it intersects both beams and utilizes the precise knowledge of the jet atomic hydrogen beam polarization to measure the analyzing power in proton-proton elastic scattering in the Nuclear Coulomb Interference (CNI) region at the prescribed RHIC proton beam energy. The reverse reaction is used to assess the absolute beam polarization. Simultaneous measurements taken with fast high statistics polarimeters that measure the p-Carbon elastic scattering process also in the CNI region use the jet results to calibrate the latter

2007-06-25

245

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. (author)

1992-05-17

246

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

Science.gov (United States)

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

Liao, Jiarui

247

Measurements of radioactive dusts in high altitude air  

Energy Technology Data Exchange (ETDEWEB)

The radioactivities of the airborne dusts were measured in samples collected by an aircraft of the Japan Air Self-Defense Force in high altitude during the period between April 1998 and March 1999. The data of the gross beta activities, gamma nuclide determination and radiochemical analysis show that there is no appreciable difference from the activity leveles of the year before and seasonal variations are becoming not so clear, that shows the radioactivities in high altitude is stable in low level. (author)

Sato, Mihoko; Endo, Hiromu; Harukawa, Junichi; Watanabe, Kenji; Katoh, Michihiko; Ogino Kumiko [Japan Defence Agency, Tokyo (Japan). First Research Center

1999-09-01

248

Measurements of radioactive dusts in high altitude air  

International Nuclear Information System (INIS)

The radioactivities of the airborne dusts were measured in samples collected by aircrafts of the Japan Air Self-Defense Force in high altitude during the period between April 1999 and March 2000. The data of the gross beta activities, gamma nuclide determination and radiochemical analysis show that there is no appreciable difference from the activity levels of the year before and seasonal variations are becoming not so clear, that shows the radioactivities in high altitude is stable in low level. (author)

2000-07-01

249

Measurements of radioactive dusts in high altitude air  

International Nuclear Information System (INIS)

The radioactivities of the airborne dusts were measured in samples collected by an aircraft of the Japan Air Self-Defense Force in high altitude during the period between April 1998 and March 1999. The data of the gross beta activities, gamma nuclide determination and radiochemical analysis show that there is no appreciable difference from the activity levels of the year before and seasonal variations are becoming not so clear, that shows the radioactivities in high altitude is stable in low level. (author)

1999-09-01

250

Natural radioactivity measurements at the proposed nuclear power plant site  

International Nuclear Information System (INIS)

Natural radioactivity measurement in the Philippines aims to establish baseline radioactivity levels in the environment of items essential to man. In this article, results of the environmental surveillance conducted in Bagac, Bataan from 1973 to 1974 are presented. Analyses were made on air parti-culates, sea and fresh water, grass, and soil samples for gross beta-gamma activities. Results obtained showed activity levels below the maximum permissible concentration recommended by the International Committee on Radiation Protection (ICRP)

1976-01-01

251

Measurements of absolute delayed neutron yield and group constants in the fast fission of 235U and 237Np  

International Nuclear Information System (INIS)

The delayed neutron activity resulting from the fast induced fission of 235U and 237Np has been studied. The six-group decay constants, relative abundances, and absolute yield of delayed neutrons from fast fission of 235U and 237Np were measured using the Godiva IV fast assembly at the Los Alamos Critical Experiments Facility. The absolute yield measured for 235U was 0.0163 ± 0.0008 neutron/fission. This value compares very well with the well-established Keepin absolute yield of 0.0165 ± 0.0005. The absolute yield value measured for 237Np was 0.0126 ± 0.0007. The measured delayed neutron parameters for 235U are corroborated with period (e-folding time) versus reactivity calculations

1998-03-01

252

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.)

1982-01-01

253

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1985-01-01

254

Sonographic Measurement of Absolute and Relative Renal Length in Healthy Isfahani Adults  

Directory of Open Access Journals (Sweden)

Full Text Available Background: There is no information on renal size and its relation to age, sex and height in the area of Isfahan. The aim of this study was to define sonographically measured absolute renal lengths and their relations to height in normal Isfahani adults. Methods: 400 healthy Isfahani subjects aged 20 to 69 years with normal blood pressure, no history of renal disease in them or their first degree relatives and with normal sonographic appearance were chosen in 2002-2003. The study was cross-sectional. With real-time sonography, absolute renal length was measured. Results: Four hundred healthy adults (230 men and 170 women aged 20 to 69 years (39.6 ± 13.6 year were evaluated. The length of left kidney was longer than the right one (111 ± 9.8 mm vs. 109 ± 8.4 mm in right kidney; P < 0.01. Renal length was significantly greater in males compared to females (P < 0.01. Renal length decreased with age and the rate of decrease was accelerated at the age of 60 years and older. There was a significant correlation between kidney length and the subject's height (P < 0.01. Conclusion: The result of this study shows the normal values for renal length in Iranian males and females, which may be helpful in assessing the size of patients’ kidneys in different clinical settings. Keywords: Kidney size, Renal length, Ultrasonography, Normal values.

A Hekmatnia

2004-04-01

255

Absolute and relative isotope abundances measured by tunable diode laser spectroscopy  

International Nuclear Information System (INIS)

The potential for measuring absolute and relative isotope abundances by high resolution spectroscopy with tunable diode lasers as sources was studied. In order to achieve the sensitivity necessary to determine the absolute abundances of molecules containing long-lived radionuclides such as 14C and 129I, a resonant spectrophone based on the photoacoustic effect was used for detection. For safety, NH3 was used as a sample with air as a buffer gas when characterizing the performance of the TDL-spectrophone system. Frequency modulation of the TDL was employed. The optimum operating pressure was found to be 6.6 kPa(50 Torr). Substitution of Kr as a buffer gas yielded a fourfold increase in signal. It is estimated that with currently available TDLs a photoacoustic spectrometer should be capable of detecting 14CO2 and CH129I at the levels present in nuclear reactor containment gases. An isotope shift of CH3129I relative to CH3127I in the nu6 band of (0.0135 +/- 0.0006) cm-1 was measured by TDL linear absorption spectroscopy

1984-01-01

256

Measurements of absolute total cross sections for electron scattering from triatomic polar molecules: SO2 and H2S  

International Nuclear Information System (INIS)

Absolute total electron-scattering cross sections (TCSs) have been measured in the energy range from 0.5 to 370 eV for SO2 and from 6 to 370 eV for H2S molecules. Measurements have been carried out using modified electron spectrometer working in a linear transmission mode. The present results are compared to published experimental TCS data. Some aspects important for achieving accurate absolute total cross sections in an electron transmission experiment are discussed

2003-09-01

257

Absolute sphericity measurement: a comparative study of the use of interferometry and a Shack-Hartmann sensor.  

Science.gov (United States)

A comparison of absolute sphericity measurements with a ShackHartmann sensor and a TwymanGreen interferometer is presented. The absolute deviations of a test sphere from its ideal shape were calculated in both cases from the measured wave aberrations of three different positions. Very good qualitative and quantitative agreement of the results was achieved. The difference of the root-mean-square values of the two methods was 1/1000 of a wavelength. PMID:18087327

Pfund, J; Lindlein, N; Schwider, J; Burow, R; Blümel, T; Elssner, K E

1998-05-15

258

Absolute distance measurement by intensity detection using a mode-locked femtosecond pulse laser.  

Science.gov (United States)

We propose an interferometric method that enables to measure a distance by the intensity measurement using the scanning of the interferometer reference arm and the recording of the interference fringes including the brightest fringe. With the consideration of the dispersion and absorption of the pulse laser in a dispersive and absorptive medium, we investigate the cross-correlation function between two femtosecond laser pulses in the time domain. We also introduce the measurement principle. We study the relationship between the position of the brightest fringe and the distance measured, which can contribute to the distance measurement. In the experiments, we measure distances using the method of the intensity detection while the reference arm of Michelson interferometer is scanned and the fringes including the brightest fringe is recorded. Firstly we measure a distance in a range of 10 µm. The experimental results show that the maximum deviation is 45 nm with the method of light intensity detection. Secondly, an interference system using three Michelson interferometers is developed, which combines the methods of light intensity detection and time-of-flight. This system can extend the non-ambiguity range of the method of light intensity detection. We can determine a distance uniquely with a larger non-ambiguity range. It is shown that this method and system can realize absolute distance measurement, and the measurement range is a few micrometers in the vicinity of Nlpp, where N is an integer, and lpp is the pulse-to-pulse length. PMID:24921740

Wu, Hanzhong; Zhang, Fumin; Cao, Shiying; Xing, Shujian; Qu, Xinghua

2014-05-01

259

Methods for precise absolute gamma-spectrometric measurements of uranium and plutonium isotopic ratios  

International Nuclear Information System (INIS)

A new gamma-spectrometric method for precise absolute (i.e. without use of standards) measurements of the uranium isotopic ratio is proposed. The method is based on intrinsic self-calibration of gamma-spectrometric measurements and on a new approach to the data treatment which allows even the most advanced pocket programmable calculators (e.g. TI-59) to be used to resolve a multiline 92.8 keV peak, unresolvable by gamma spectrometers. The narrow energy range of the uranium gamma spectrum (92-99 keV) is only used for uranium isotopic ratio measurements, which makes the results reliable and precise, and they do not depend on the size, shape and type of the material. Two new approaches to Pu-Am absolute gamma-spectrometric isotopic ratio measurements are reported. In the first the energy ranges, 250-414 and 148-208 keV, are used. The first is for 241Pu/239Pu and 241Am/241Pu isotopic ratio determination on the basis of gamma rays in the narrow range, 332.354-345.014 keV; the second is for 238Pu/241Pu and 240Pu/241Pu determinations using neighbouring gamma lines of corresponding isotopes, which is suitable for large samples when the thickness of the container wall is large. The precision of the 238Pu determination is not very good. The second approach mainly uses the low-energy range, 94-105 keV, where practically all isotopes emit strong gamma or X-ray lines. The precision of the isotopic ratio determination in this case is significantly higher, particularly for 238Pu/241Pu and 240Pu/241Pu. A high-resolution gamma-spectrometric system in the 90-210 keV range is required for these measurements. (author)

1978-10-06

260

Radiation Protection Research: Low-level Radioactivity Measurements  

Energy Technology Data Exchange (ETDEWEB)

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'.

Hurtgen, C

2000-07-01

 
 
 
 
261

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

2006-01-01

262

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$

2008-02-01

263

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)

2009-04-01

264

Absolute measurements of the high-frequency magnetic dynamics in high-$T_c$ superconductors  

CERN Multimedia

We review recent measurements of the high-frequency dynamic magnetic susceptibility in the high-$T_c$ superconducting systems La$_{2-x}$Sr$_{x}$CuO$_4$ and YBa$_2$Cu$_3$O$_{6+x}$. Experiments were performed using the chopper spectrometers HET and MARI at the ISIS spallation source. We have placed our measurements on an absolute intensity scale, this allows systematic trends to be seen and comparisons with theory to be made. We find that the insulating S=1/2 antiferromagnetic parent compounds show a dramatic renormalization of the spin wave intensity. The effect of doping on the response is to cause broadenings in wave vector and large redistributions of spectral weight in the frequency spectrum.

Hayden, S M; Dai, P; Mook, H A; Perring, T G; Cheong, S W; Fisk, Z; Dogan, F; Mason, T E

1997-01-01

265

Absolute measurements of the high-frequency magnetic dynamics in high-{Tc} superconductors  

Energy Technology Data Exchange (ETDEWEB)

The authors review recent measurements of the high-frequency dynamic magnetic susceptibility in the high-T{sub c} superconducting systems La{sub 2{minus}x}Sr{sub x}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 6+x}. Experiments were performed using the chopper spectrometers HET and MARI at the ISIS spallation source. The authors have placed their measurements on an absolute intensity scale, this allows systematic trends to be seen and comparisons with theory to be made. They find that the insulating S = 1/2 antiferromagnetic parent compounds show a dramatic renormalization in the spin wave intensity. The effect of doping on the response is to cause broadenings in wave vector and large redistributions of spectral weight in frequency.

Hayden, S.M. [Univ. of Bristol (United Kingdom). H.H. Wills Physics Lab.; Aeppli, G. [NEC Research Inst., Princeton, NJ (United States); Dai, P.; Mook, H.A. [Oak Ridge National Lab., TN (United States); Perring, T.G. [Rutherford Appleton Lab., Chilton (United Kingdom); Cheong, S.W. [Lucent Technologies, NJ (United States). Bell Labs.; Fisk, Z. [Florida State Univ., Tallahassee, FL (United States). Dept. of Physics; Dogan, F. [Univ. of Washington, Seattle, WA (United States). Dept. of Material Science and Engineering; Mason, T.E. [Univ. of Toronto, Ontario (Canada). Dept. of Physics

1997-08-07

266

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

Science.gov (United States)

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 Y337=5.61±0.06stat±0.22syst 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.

Ave, M.; Bohacova, M.; Curry, E.; Di Carlo, P.; Di Giulio, C.; Facal San Luis, P.; 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.; Rouille D'Orfeuil, B.; Salamida, F.; Schovanek, P.; Smida, R.; Spinka, H.; Ulrich, A.; Verzi, V.; Williams, C.

2013-02-01

267

Measurement of the absolute neutron activity of a 252Cf source  

International Nuclear Information System (INIS)

A method for measuring the absolute neutron activity of a large 252Cf source has been developed. The neutron counting assembly is composed of eight BF3 counters mounted in a large tank filled with water which is used as a moderator. The detection efficiency is determined using a low activity 252Cf source. The mehod is based on the identification of every fission event, followed by the counting of the fission neutrons detected by the BF3 counters during a time interval equal to the maximum neutron lifetime in the moderator. The efficiency is thus obtained relative to the average number of prompt neutrons emitted per 252Cf spontaneous fission which is commonly used as a standard. A systematic analysis of the different sources of error is presented. The measurement accuracy is estimated to be better than 1%

1977-01-01

268

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

Science.gov (United States)

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. PMID:23635195

Casey, D T; Frenje, J A; Johnson, M Gatu; Séguin, F H; Li, C K; Petrasso, R D; Glebov, V Yu; Katz, J; Magoon, J; Meyerhofer, D D; Sangster, T C; Shoup, M; Ulreich, J; Ashabranner, R C; Bionta, R M; Carpenter, A C; Felker, B; Khater, H Y; LePape, S; MacKinnon, A; McKernan, M A; Moran, M; Rygg, J R; Yeoman, M F; Zacharias, R; Leeper, R J; Fletcher, K; Farrell, M; Jasion, D; Kilkenny, J; Paguio, R

2013-04-01

269

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

270

Absolute work function measurements with the retarding potential method utilizing a field emission electron source  

Science.gov (United States)

The absolute work function of a scandate cathode is measured by a newly developed retarding potential method utilizing a titaniated W(100) field electron emission source reference. The electron trajectories in the lens system are computed to determine the conditions of the parallel beam impinging on the sample. The experimental results show a good agreement with the computations. The extremely low work function (˜ 1.2 eV) of the scandate cathode is obtained for the first time with this method. A systematic work function drift is observed during repeated work function measurements, suggesting the possibility of surface atom movement caused by the very low-energy electron beam irradiation of 1 to 2 eV.

Yamamoto, Shigehiko; Watanabe, Isato; Sasaki, Susumu; Yaguchi, Tomio

1992-04-01

271

Measurement of absolute activity of thin-layer beta sources using two-chamber 4?-counter  

International Nuclear Information System (INIS)

The method to measure the absolute activity of ?-radiation source using a two-chamber gas discharge 4?-counter is suggested. The method ensures a high accuracy and account of absorption of spectrum soft constituent in the sublayer, which permits to use substrate of different thickness (up to the layer of half absorption). The method is tested using the sources: "1"4C(0.155 MeV), "2"0"4Tl(0.765 MeV), "3"2P(1.708 MeV) and equilibrium mixture "9"0Sr-"9"0Y(0.61; 2.27 MeV). Aluminium foils of 0.5 half asorption layer thick served as substrates. Statistical error of each measurement never exceeded 0.5%

1986-01-01

272

Measurements of radioactive dusts in high altitude air  

Energy Technology Data Exchange (ETDEWEB)

The radioactivities of the airborne dusts were measured in samples collected by aircrafts of the Japan Air Self-Defense Force in high altitude during the period between April 2000 and March 2001. From June 2000 the newly designed filters composed of electret filter and fibrous activated carbon filter were used to collect air suspended dust and radioactive gas at the same time. The data of the gross beta activities, gamma nuclide determination and radiochemical analysis show that there is no appreciable difference from the activity levels of the year before and seasonal variations are becoming not so clear, that shows the radioactivities in high altitude is stable in a low level. Radioactive gas (gaseous radioiodine) was not detected. (author)

Ogino, Kumiko; Sato, Mihoko; Harukawa, Junichi; Katoh, Michihiko [Japan Defence Agency, Tokyo (Japan). First Research Center

2001-08-01

273

Assembly for measuring concentrations of radioactivity  

International Nuclear Information System (INIS)

The assembly for measuring the activity of noble gases and aerosols uses a ?-measuring equipment. A compressor conveys the substances into the measuring space enclosed by a Pb or W shielding. Within the same shielding there are arranged a second measuring chamber plus detector for background compensation and a third measuring chamber plus detector for measurement of the aerosol concentration, e.g. for determination of the dose caused by incorporation. For this purpose there is provided for an aerosol filter. The compressor can transport the gases or aerosols through all three chambers if the aerosol filter is connected between the first and second measuring chamber and the compressor is connected between the first measuring chamber and the aerosol filter. (DG)

1979-01-01

274

Evaluation of the systematic shifts and absolute frequency measurement of a single Ca+ ion frequency standard  

Science.gov (United States)

This paper provides a detailed description of the 40Ca+ optical frequency standard uncertainty evaluation and the absolute frequency measurement of the clock transition, as a summary and supplement for the published papers of Yao Huang et al. (Phys Rev A 84:053841, 1) and Huang et al. (Phys Rev A 85:030503, 2). The calculation of systematic frequency shifts, expected for a single trapped Ca+ ion optical frequency standard with a "clock" transition at 729 nm is described. There are several possible causes of systematic frequency shifts that need to be considered. In general, the frequency was measured with an uncertainty of 10-15 level, and the overall systematic shift uncertainty was reduced to below a part in 10-15. Several frequency shifts were calculated for the Ca+ ion optical frequency standard, including the trap design, optical and electromagnetic fields geometry and laboratory conditions, including the temperature condition and the altitude of the Ca+ ion. And we measured the absolute frequency of the 729-nm clock transition at the 10-15 level. An fs comb is referenced to a hydrogen maser, which is calibrated to the SI-second through the Global Positioning System (GPS). Using the GPS satellites as a link, we can calculate the frequency difference of the two hydrogen masers with a long distance, one in WIPM (Wuhan) and the other in National Institute of Metrology (NIM, Beijing). The frequency difference of the hydrogen maser in NIM (Beijing) and the SI-second calculated by BIPM is published on the BIPM web site every 1 month, with a time interval of every 5 days. By analyzing the experimental data obtained within 32 days of a total averaging time of >2 × 106 s, the absolute frequency of the 40Ca+ 4 s 2 S 1/2-3 d 2D5/2 clock transition is measured as 411 042 129 776 393.0 (1.6) Hz with a fractional uncertainty of 3.9 × 10-15.

Huang, Yao; Liu, Peiliang; Bian, Wu; Guan, Hua; Gao, Kelin

2014-01-01

275

Preliminary results of absolute and high-precision gravity measurements at the Nevada Test Site and vicinity, Nevada  

International Nuclear Information System (INIS)

Absolute gravity measurements were made at 4 sites in southern Nevada using the absolute gravity free-fall apparatus. Three of the sites are located on the Nevada Test Site at Mercury, Yucca Pass, and in northern Jackass Flats. The fourth site is at Kyle Canyon ranger station near Charleston Park where observed gravity is 216.19 mGal lower than at Mercury. Although there is an uncertainty of about 0.02 mGal in the absolute measured values, their gravity differences are considered accurate to about 0.03 mGal. Therefore, the absolute measurements should provide local control for the calibration of gravity meters between Mercury and Kyle Canyon ranger station to about 1 to 2 parts in 10,000. The average gravity differences between Mercury and Kyle Canyon obtained using LaCoste and Romberg gravity meters is 216.13 mGal, 0.06 mGal lower, or 3 parts in 10,000 lower than using the absolute gravity meter. Because of the discrepancy between the comparison of the absolute and relative gravity meters, more absolute and relative gravity control in southern Nevada, as well as the Mt. Hamilton area where the LaCoste and Romberg instruments were calibrated, is needed. Multiple gravity meter ties were also made between each of the four absolute stations to nearby base stations located on bedrock. These stations were established to help monitor possible real changes in gravity at the absolute sites that could result from seasonal variations in the depth to the water table or other local mass changes. 8 refs., 16 figs., 7 tabs

1988-01-01

276

Optical parameters Determination for absolute luminosity and total cross section measurements in ATLAS  

CERN Multimedia

ALFA (Absolute Luminosity For ATLAS) aims at measuring the absolute luminosity for the ATLAS experiment with an incertitude down to 2-3 \\% and the total elastic cross section. The luminosity is related to the number of events, the highest the luminosity, the highest the number of events. This is, then, an important quantity for colliders like LHC (Large Hadron Collider). LHC is made of two beams circulating in two different beam pipes and colliding at four interaction points where the four physics experiments are located (ATLAS, CMS, ALICE, LHCb). ALFA detectors inserted into Roman Pots (RPs), have been placed around ATLAS at 240 m distance from the collision point (IP1) after six quadrupoles magnets and two dipoles defining the ALFA beam line which is part of the LHC ring.The detectors are made of scintillating optics fibers to catch elastic protons generated at IP1. These protons are tracked through the LHC magnets beam line which needs to be optimized in terms of optics parameters. We call high ? optics, ...

Cavalier, Sophie

277

A low noise highly integrated bolometer array for absolute measurement of VUV and soft x radiation  

International Nuclear Information System (INIS)

A new low noise miniaturized multichannel bolometer module for absolute measurements in the VUV and soft x spectral ranges is described. Highly integrated four-channel modules (2x3.3x1.5 cm3) each comprising four independent ac-excited (50 kHz) metal resistor bolometer bridges were successfully tested on a large tokamak (Tore Supra in Cadarache) and on an electron synchrotron (BESSY in Berlin). The bolometer system features a linear response to the absorbed radiation power, a low detection limit (?1.0x10-6 W cm-2 on Tore Supra with an integration time of ?int=10x10-3 s) and a low NEP (?10x10-9 W on BESSY). The thermal cross-talk between adjacent detectors is negligible (Br/?T -4 V degree C-1 is achieved. It can be operated at a maximum temperature of 150 degree C, at high magnetic fields (tested up to B=4.5 T in the laboratory) and survives high nuclear radiation doses. The system offers the possibility of detecting low-power VUV and soft x-radiation with sampling rates of up to 10 kHz on plasma machines and of absolutely calibrating VUV and soft x instruments. Effective suppression of electric, thermal and nuclear radiation interferences is characteristic of the bolometer system.Strain gauge effects, which could affect the behavior of the bolometers at high magnetic fields, are suppressed by the ac-excitation technique

1991-01-01

278

Measurement of the Water Content of Snow with Radioactive Isotopes.  

Science.gov (United States)

The measurement of the water content of snow using radioactive isotopes is based on the principle of measurement of the attenuation of the flux of gamma rays by the snow cover from a source situated beneath the snow cover. As the source it is possible to ...

A. A. Sapozhnikov M. S. Sternzat

1965-01-01

279

Measurement of radon and thoron daughters in indoor air by absolute beta counting  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Active grab sampling device was used for sampling of radioactive aerosol particles. Air was drawn through a glass-fibre filter by common vacuum cleaner. After the sampling the filter was placed under an end-window GM counter and the total beta-counting rate in the function of the time was measured. The complex decay curve could be analyzed by a computer program which is able to separate the contributions of the different isotopes to the total rate and to compute the air concentrations from th...

PAPP ZOLTÁN; DARÓCZY SÁNDOR; Papp Zoltán (1959-) (fizikus)

1993-01-01

280

Determination of the atmospheric radioactivity by measuring the radioactivity of aerosol specimens  

International Nuclear Information System (INIS)

In order to control the radioactive pollution of the atmosphere in the surrounding of the 10 kW experimental nuclear reactor of the Budapest Technical University a series of measurements of the radioactivity of aerosol samples were carried out. The cotton wool-like FPP-15 filter was changed in the intermittent aerosol sampling device three times a week. The specific beta activity of the samples was determined by help of a GM-tube calibrated by the beta radiation of 40K with 1.35 MeV end-point-energy. The results do not show any escape of radioactive matter into the environment. The smallest traceable specific activity was 0.02 pCi/m3. (Sz.Z.)

1975-01-01

 
 
 
 
281

A pulse-recording system for radioactivity measurements  

CERN Document Server

The NIST Radioactivity Group is developing a computer-based pulse-recording system to use for radioactivity measurements. The system consists of a dual ADC module and a plug-in board for an industry-standard-architecture personal computer. The host computer (or another computer) can be programmed to simulate many different logic systems (coincidence, anticoincidence, selective sampling, correlation counting, etc.), so that the pulse data from a given measurement can be analyzed using a wide range of timing parameters and types of logic.

Lucas, L L

1998-01-01

282

A measurement of absolute cross sections for multielectron processes in slow collisions between highly charged ions and atoms  

International Nuclear Information System (INIS)

In this experiment absolute cross sections for single and multielectron processes in slow collisions, A"q"++B?A"r"++B"s"++(r+s-q)e"-, have been measured. By means of a coincidence time-of-flight technique, the charge state of the projectile before and after the collision and the charge state of the target after the collision are determined. The experimental technique is discussed together with simple models for absolute cross sections. (orig.)

1987-04-01

283

Influence of radioactive impurities on SIR measurements  

International Nuclear Information System (INIS)

The correction usually applied to an SIR measurement in the presence of a gamma-ray emitting impurity is presented and explained. The method of calibration of a Ge(Li) spectrometer is briefly described. It is used to look for impurities when SIR measurements show inconsistencies. An example is presented where a 103Ru impurity was discovered in a 99Mo solution. The correction applied compensates for the decrease of around 0.2% per day observed in the SIR measurements of this 99Mo ampoule

2000-03-01

284

Diffusion coefficient measurements with radioactive tracer technique  

International Nuclear Information System (INIS)

A measuring cell and a new method were developed to study chloride ion diffusion through thin layers and to measure diffusion coefficient. ?-radiation of the tracer was detected making use of Cherenkov radiation. The chamber developed is suitable for diffusion test with any ?-decay nuclide with a maximum energy higher than the Cherenkov threshold referring to water. The results obtained were checked by GM counting. The method was used for testing paint films and coating systems. The diffusion developed in the layer was computer simulated and the results were compared to measured data. (author)

1985-01-01

285

Coincidence system for the absolute measurement of radionuclides activity using a liquid scintillator  

International Nuclear Information System (INIS)

A system for the standartization of radioisotopes activity using liquid scintillator detector was developed. The system was set up at Nuclear Metrology Laboratory - L.M.N. (Nuclear Physics Division - IEA). The system performance was checked by absolute activity measurements for two radioisotopes, "6"0Co and "2"4"1Am. The activities were determined by the 4?(?, ?-?) coincidence method. An accuracy of the order of 99,8% was obtained. The results for "6"0Co were compared with those obtained by 4??-? coincidence method using a proportional counter at L.M.N., while the results for "2"4"1Am were compared with those obtained through the linear extrapolation method using the same liquid scintillator. Compared to other systems, the advantages of this one are the simplicity and the short time spent in the sample preparation, and the negligible self-absorption. (Author)

1979-06-01

286

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

287

Absolute Polarization Measurements at RHIC in the Coulomb Nuclear Interference Region  

CERN Document Server

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.

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

288

Heterodyne measurements of electron cyclotron emission from Alcator A and absolute submillimeter receiver calibration  

International Nuclear Information System (INIS)

Electron cyclotron emission (ECE) from thermal plasmas in the Alcator A tokamak for harmonics from 2nd through 5th and up to the 7th harmonic for nonthermal plasmas have been observed in the frequency range of 400--800 GHz using a sensitive, low-noise submillimeter heterodyne receiver. The sensitivity of the receiver (approx.10-20 W Hz-1) allowed for the measurement of 4th and 5th harmonic ECE from thermal plasmas with T/sub e/roughly-equal800 eV. The receiver was absolutely calibrated and its field of view was experimentally determined. A careful analysis has been made to relate the receiver calibration to the plasma-emitting volume, taking into account radiation coherence time, wall reflections, polarization scrambling, window losses, and aperture restrictions

1981-01-01

289

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

DEFF Research Database (Denmark)

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

Menn, W.; Hof, M.

1996-01-01

290

Absolute measurements of the elastic constants of nematic liquid crystals by light scattering  

International Nuclear Information System (INIS)

The absolute determination of the three Frank elastic constants of nematic liquid crystals (MBBA) has been performed by light scattering differential-cross-section measurements. The use of an optimized oblique-incidence geometry allows us to reduce several causes of error, like multiple scattering and spurious scattering due to crystal defects. All the three elastic constants have been obtained on the same specimen homeotropically aligned without changing the alignment of the director, thus reducing boundary distortion effects. It will be shown that the new technique has several advantages with respect to previously used ones. A full description of the experimental arrangement and a discussion of the obtained results is given in the text. (author)

1981-12-11

291

Heat-capacity measurements and absolute entropy of ?-Mg2PO4OH  

Science.gov (United States)

The low-temperature heat capacity of ?-Mg2PO4OH was measured between 10 and 400 K by adiabatic calorimetry. No phase transition was observed over this temperature range. A relative enthalpy increment of 22,119 J mol-1 and an absolute entropy value of 127.13±0.25 J mol-1 K-1 at 298.15 K are derived from the results. The low-temperature heat-capacity data are compared with the DSC data obtained from 143 K to 775 K and show marginal differences in the common temperature range. The latter data are fitted by the polynomial C_p = { {316.62 - 2957 T^{ - 0.5} - 563350 T^{ - 2} + 955.55 × 10^5 T^{ - 3} } {J} {{K}}^{ - 1} {{mol}}^{ - 1} , which allows extrapolation to high temperatures.

Leyx, Catherine; van Miltenburg, J. Cornelis; Chopin, Christian; Cemi?, Lado

2005-05-01

292

Measurement of steam velocity using radioactive tracers  

International Nuclear Information System (INIS)

Measurements of steam velocity are to be carried out on completion of the Ohaki geothermal power station to calibrate a Venturi meter to be used there for assessing generation efficiency. This report describes the development of the measurement method, designed to conform as much as possible to the appropriate British standard, and two tests of it that were carried out under similar conditions at the Wairakei power station. The experience gained will enable the measurements at Ohaki to be carried out in the most efficient manner possible. Although there were only two runs in which the full detection system and the full amount of tracer were used it maybe concluded that the measurements will yield values within +-1% of the true velocities

1986-01-01

293

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

Science.gov (United States)

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 account the impact of research findings while keeping in mind the physical and intellectual contributions of the author(s) in accomplishing the task. The Ab-index and h-index were calculated for 10 highly cited geneticists and molecular biologist and 10 young researchers of biological sciences and compared for their relationship to the researchers input as a primary author. This is the first report of a measuring method clarifying the contributions of the first author, corresponding author, and other co-authors and the sharing of credit in a logical ratio. A java application has been developed for the easy calculation of the Ab-index. It can be used as a yardstick for comparing the credibility of different scientists competing for the same resources while the Productivity index (Pr-index), which is the rate of change in the Ab-index per year, can be used for comparing scientists of different age groups. The Ab-index has clear advantage over other popular metric systems in comparing scientific credibility of young scientists. The sum of the Ab-indices earned by individual researchers of an institute per year can be referred to as Pr-index of the institute.

Biswal, Akshaya Kumar

2013-01-01

294

Measurements of radioactive dust in high altitude air  

International Nuclear Information System (INIS)

The radioactivity in samples of airborne dust was measured. The samples had been collected at high altitude by the Japan Air Self-Defense Force. The data were obtained for the gross beta activity, gamma nuclide determination and radiochemical analysis. It was shown that there was no appreciable difference between the activity levels obtained in this time and in the year before. Seasonal variations were not very pronounced. It was found that the radioactivity at high altitude had been stable at a low level. Radioactive gases (gaseous radioiodine and xenon gas) were not detected. This report does not include the result on radionuclide measurements that Technical Research and Development Institute executed for examining the nuclear emergency situation at Fukushima Daiichi and Daini nuclear power plants after Tohoku Region Pacific Ocean Earthquake on March 11, 2011. (author)

2012-03-01

295

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

1992-01-01

296

Determination and control measurements of coincidence devices used for activity measurements by absolute method  

International Nuclear Information System (INIS)

Description of the method of performing determination and control measurements is given which are done on the measuring device with 4?-proportional counter under elevated pressure. The device is working according to the coincidence method. Accuracy of this method greatly depends on determination of electronic parameters and different correction facters. Control measurements are done for testing the state of the counter and electronic circuit of the device for determination of the energy equivalent for descrimination level of 4?-proportional counter; for determination of the resolution ability of the counter, for determination of first and coincidence time. Determination measurements are done for testing a tuning of the device for measurement of the given nuclide and include a turing of ?-chanel; measurement of activity of ?-emitter with continious spectrum; measurement of activity of nuclides with discrete spectrum; turing of ?-chanel; turing of the coincidence circuit. The method of plotting of the curve for data extrapolation is given

1979-05-18

297

Absolute measurement of the activity of sup 2 sup 2 sup 2 Rn using a proportional counter  

CERN Document Server

A measuring set-up comprising a proportional counter of calculable sup 2 sup 2 sup 2 Rn efficiency and quantifiable active volume (delta sub V <0.1%) is described. On account of the special design of the end caps, the counter is suitable for absolute activity measurements on gaseous radiation sources. The sup 2 sup 2 sup 2 Rn efficiency is determined by computer simulation of the measured alpha-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 sup 2 sup 2 sup 2 Rn activity is proved by experiments. Thus, a new method for the realization of the unit of activity of sup 2 sup 2 sup 2 Rn is obtained, which is independent of the unit of activity of sup 2 sup 2 sup 6 Ra.

Busch, I; Keyser, U

2002-01-01

298

Marine radioactivity measurements with liquid scintillation spectrometers  

International Nuclear Information System (INIS)

Liquid Scintillation Spectrometry (LSS) has now become the most widespread method for quantitative analytical measurement of low levels of ?-emitting radionuclides like "3H and "1"4C. The high efficiency resulting from the latest development in LSS makes this technique not only appropriate but also enables direct measurement in environmental samples without excessive preparation. The introduction of several new cocktails based on solvents with a high flashpoint containing surfactants and having a high degree of aqueous sample compatibility has also contributed to the simplification of procedures

1999-07-01

299

Techniques for radioactivity measurement in water, suspensions and sediments  

International Nuclear Information System (INIS)

The measurements to determine the overall ?-radioactivity in surface water and sediment samples are intended as monitoring measurements to reveal long-term trends, as well as to detect uncontrolled release of radioactivity. The measurements to determine the overall ?-radioactivity in surface water and sediment samples are likewise a monitoring method to detect all radioecologically relevant nuclides in one process. This method can be applied under certain conditions as a means of controlling whether the dose limits set in section 45 of the Radiation Protection Ordinance are exceeded. Liquid scintillation spectrometry is usually applied to detect tritium within the framework of environmental monitoring. Gamma spectrometry using Ge(Li) detectors allows simultaneous determination of various radionuclide fractions in complex nuclide compositions. For this purpose, large-volume water samples have to be pre-treated because of their very low nuclide concentrations (50-100 l). Radioactivity release after incidents has to be controlled by direct measurement, using appropriate counting systems (ring dishes). Radionuclides are primarily adsorbed by suspended particles where they can be detected and measured with great sensitivity, just as in sediments. (orig./HP)

1983-06-01

300

Absolute measurement of the cross section for 23 keV neutron activation of thorium  

International Nuclear Information System (INIS)

Measurement has been made of the thorium radiative capture cross section using Sb-Be photoneutrons and an absolute activation method. The average of two determinations gave a value of 604 mb at 23 keV neutron energy with a 4% estimated error from all sources (+-1 sigma). In each experiment, a cylindrical shell target of natural thorium metal was irradiated for approximately two weeks by a centrally-positioned Sb-Be source. The accumulated 27-day half-life 233Pa, activated by neutron capture in thorium, was recovered by solvent extraction with diisobutylcarbinol after first dissolving the target in hydrochloric acid. Ninety percent recovery of protactinium was obtained, as measured by isotopic tracing with 232Pa. The 1.3-day half-life 232Pa had to be produced immediately before each use. A thin thorium foil was irradiated with 11 MeV protons using a tandem van de Graaff accelerator. The 232Pa was then recovered by chemical separation. 233Pa activity was measured by counting the 312-keV decay gamma with a Ge(Li) detector. Detector efficiency was determined by indirect calibration against a 237Np deposit assayed by alpha counting at the National Bureau of Standards. The Sb-Be source strength was measured by the manganese bath method, using a 252Cf source for calibration, traceable to the NBS II neutron standard. Flux per unit source strength was determined by Monte Carlo modelling of the source/target irradiation geometry

1981-01-01

 
 
 
 
301

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)

1983-01-01

302

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)

1987-01-01

303

Gamma, radon, natural radioactivity measurements in Chile  

International Nuclear Information System (INIS)

Different natural radiation measurements, performed since 1983, are analysed and discussed regarding the average effective population dose. A decade of absorbed gamma dose measurements in air (1983-93), were carried out using compensated TLD detectors, during long periods of integration time and with a network of 11 stations, along the country, from Arica to the Antarctic territory. An indoor Rn-222 and gamma survey dwellings, in high background zones, underground mines and drinking water was started in 1988 using different kind of detectors, including electret radon chambers. The methods, dose assessments and results are presented and discussed in the frame of worldwide average effective population doses. None of the average effective doses found over the evaluated areas, exceed the comparison levels. (author)

1997-12-01

304

Procedural standards for radioactivity measurements. Final report  

Energy Technology Data Exchange (ETDEWEB)

The American National Standards Institute (ANSI) Committee-N42.2 has, since 1973, worked on developing procedural standards for the calibration and usage of: (a) 'dose calibrator' ionization chambers for the assay of radionuclides; (b) germanium detectors for the measurement of gamma-ray emission of radionuclides; (c) sodium iodide detector systems; (d) liquid scintillation counting systems. These procedures have become National Standards within the last 2 1/2 years. Other standards are currently being developed. The composition of the committee and writing groups, the objectives that were set in developing the procedural standards and the interactions with the appropriate regulatory groups, instrument manufacturers as well as the National Bureau of Standards are presented. The Standards included a section on precautions as well as one on the sources of error to minimize the potential of obtaining and using erroneous data and to give the user a better understanding of the measurement system.

Seidel, C.W.; Hutchinson, J.M.R.

1980-12-01

305

Measuring radon progeny and thoron progeny in air by absolute beta counting subsequent to grab sampling  

International Nuclear Information System (INIS)

A new grab sampling method for the simultaneous determination of radon progeny and thoron progeny in air has been developed and demonstrated by the first author of this paper a few years ago. The characteristics and capabilities of this method are discussed in the present paper in detail. The method is based on gross beta counting of filtered aerosol samples counted over successive time intervals using an end-window Geiger-Muller counter. The measured counting rate versus time curve is analyzed by fitting to it some linear combination of the theoretical decay curves of the decay products with the knowledge of the counting efficiencies and some other quantities. Defined solid angle absolute beta counting was used to evaluate the counting efficiencies for the decay products one by one. So, the method is an absolute one that does not demand further calibration. The decay products of radon and thoron can be determined separately and simultaneously. The systematic error of the results, deriving from the inaccurate evaluation of the counting efficiencies, is probably lower and can be estimated more surely than that of the methods based on alpha counting. The method is highly sensitive: accurate results can be obtained for 214Pb, 214Bi, 212Pb, EEDC222 and EEDC220 even outdoors. However, the results for 218Po and 212Bi are much more inaccurate and 208Tl cannot be determined at all. The reliability of the determinations can be raised significantly using conditional computations based on the information obtainable from some theoretical considerations and models. The method can be used in a broad activity concentration range, equally in caves, mines, houses or outdoors. The above characteristics and capabilities of the method are demonstrated in this paper through the detailed presentation and analysis of the results obtained for three samplings performed indoors in a house, in a cave, and outdoors, respectively. The known advantages and drawbacks of the method are also surveyed in detail

2006-05-01

306

Aerial measurements of radioactivity in the environment  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an aerial measuring system. Nuclide specific measurements of soil contamination are performed by employing a computerized gamma ray spectrometer with a high purity Ge-detector. At an altitude of 100 m, soil contaminations of some kBq/m{sup 2} of {sup 137}Cs can be measured. For the detection of sources of gamma radiation, a 12 l NaI(Tl)-detector is used. At a flight path distance of 300 m and a flight speed of 100 km/h, an area of approximately 30 km{sup 2} can be covered per hour, whereby gamma radiation sources of an activity of some GBq are still detectable from an altitude of 100 m. A satellite-navigation system is used to determine the position of the helicopter. The altitude above ground is continuously measured by radar altimeter. The results of the German team participating in an international intercomparison measuring campaign in Finland in 1995 are reported. The objective was to determine the {sup 137}Cs soil contamination in a given region and to detect unknown radiation sources and to assess their activity. (orig.) [Deutsch] Der Beitrag beschreibt ein Messverfahren fuer Radioaktivitaetsmessungen in der Umwelt vom Hubschrauber aus. Fuer die nuklidspezifische Messung der Bodenkontamination wird ein rechnergesteuertes Halbleiterspektrometer mit einem Reinstgermanium-Detektor eingesetzt. Damit koennen in einer Flughoehe von 100 m noch {sup 137}Cs-Kontaminationen von einigen kBq/m{sup 2} gemessen werden. Fuer das Aufspueren von Gammastrahlungsquellen wird ein NaI(Tl)-Szintillationsdetektor mit einem Volumen von 12 l verwendet. Bei einem Flugbahnabstand von 300 m und einer Fluggeschwindigkeit von 100 km/h kann ein Gebiet von etwa 30 km{sup 2} pro Stunde abgesucht werden, wobei Gammastrahlungsquellen mit einer Aktivitaet von einigen GBq aus einer Flughoehe von 100 m noch aufgespuert werden koennen. Ein Satellitennavigationssystem misst die Position des Helikopters, die Flughoehe wird mit einem Radarhoehenmesser bestimmt. Ergebnisse einer internationalen Vergleichsmesskampagne mit Hubschraubern in Finnland im Jahre 1995, werden vorgestellt. (orig.)

Winkelmann, I. [Bundesamt fuer Strahlenschutz, Berlin (Germany). Fachbereich Strahlenschutz; Thomas, M. [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany). Fachbereich Strahlenschutz; Carloff, G. [Grenzschutz-Fliegergruppe, Sankt Augustin (Germany)

1997-05-01

307

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)

1995-07-01

308

On the measurement of quadrupole moments of radioactive nuclei  

International Nuclear Information System (INIS)

Electric quadrupole moments provide a direct insight on the single-particle structure or the collective nature of a nuclear state. This article presents a short review on some of the experimental methods available to measure quadrupole moments with emphasis on the reorientation technique in Coulomb excitation and its use in combination with radioactive ion beams.

2011-10-31

309

(n, ?) measurements on radioactive isotopes with DANCE  

International Nuclear Information System (INIS)

The Detector for Advanced Neutron Capture Experiments (DANCE) at the Los Alamos National Laboratory (LANL) is designed as a high efficiency, highly segmented 4? BaF2 detector for calorimetrically detecting gamma rays following a neutron capture. Coupled with the neutron spallation source at the Los Alamos Neutron Science Center (LANSCE), DANCE measurements on unstable isotopes in the energy range between 10 meV and 500 keV will provide many of the missing key reactions that are needed to understand the nucleosynthesis of the heavy elements and will also provide vital information for the design of future reactor concepts

2005-12-01

310

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

International Nuclear Information System (INIS)

We report measurements of absolute transition frequencies and hyperfine coupling constants for the 8S1/2, 9S1/2, 7D3/2, and 7D5/2 states in 133Cs 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.

2010-04-01

311

Cryogenic Current Comparator for Absolute Measurement of the Dark Current of the Superconducting Cavities for Tesla  

CERN Document Server

A newly high performance SQUID based measurement system for detecting dark currents, generated by superconducting cavities for TESLA is proposed. It makes use of the Cryogenic Current Comparator principle and senses dark currents in the nA range with a small signal bandwidth of 70 kHz. To reach the maximum possible energy in the TESLA project is a strong motivation to push the gradients of the superconducting cavities closer to the physical limit of 50 MV/m. The field emission of electrons (the so called dark current) of the superconducting cavities at strong fields may limit the maximum gradient. The absolute measurement of the dark current in correlation with the gradient will give a proper value to compare and classify the cavities. This contribution describes a Cryogenic Current Comparator (CCC) as an excellent and useful tool for this purpose. The most important component of the CCC is a high performance DC SQUID system which is able to measure extremely low magnetic fields, e.g. caused by the extracted ...

Knaack, K; Wittenburg, K

2003-01-01

312

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

CERN Document Server

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...

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

2010-01-01

313

Measurement of radioactivity in agricultural products (1995-96)  

International Nuclear Information System (INIS)

Radioactivity levels and concentration of radionuclides in agricultural products like beans, sesame, potato, etc. were measured by using Low Level Beta/Alpha System and high resolution gamma-ray spectrometry system. The levels of radioactivity were found to be less than the Derivedc Intervention Level adopted by FAO/WHO Codex Alimentarius Commission in 1991 (IAEA BSS safety series No. 115-1). No artificial radionuclides such as fission products, activation products were not found whereas radionuclides found in the samples are only natural occurring radionuclide, K-40. (author)

2001-01-01

314

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

Energy Technology Data Exchange (ETDEWEB)

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.)

NONE

2001-07-01

315

Absolute measurements of fission cross sections of 235U by 14,8 MeV neutrons  

International Nuclear Information System (INIS)

Absolute measurements of fission cross-section for 235U by 14,8 MeV neutrons have been carried out by the method of companion particles with accuracy 1.7%. The sources of errors of measurements are presented. The fission cross-section obtained is equal to 2,188 +- 0.037 barns

1975-06-13

316

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

317

In-flight measurement of the absolute energy scale of the Fermi Large Area Telescope  

CERN Document Server

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 pul...

,

2011-01-01

318

An Absolute Measurement of the Cosmic Microwave Background Radiation Temperature at 10.7 GHz  

CERN Document Server

A balloon-borne experiment has measured the absolute temperature of the cosmic microwave background radiation (CMBR) at 10.7 GHz to be Tcmbr = 2.730 +- .014 K. The error is the quadratic sum of several systematic errors, with statistical error of less than 0.1 mK. The instrument comprises a cooled corrugated horn antenna coupled to a total-power radiometer. A cryogenic mechanical waveguide switch alternately connects the radiometer to the horn and to an internal reference load. The small measured temperature difference (<= 20 mK) between the sky signal and the reference load in conjunction with the use of a cold front end keeps systematic instrumental corrections small. Atmospheric and window emission are minimized by flying the instrument at 24 km altitude. A large outer ground screen and smaller inner screen shield the instrument from stray radiation from the ground and the balloon. In-flight tests constrain the magnitude of ground radiation contamination, and low level interference is monitored through ...

Staggs, S T; Meyer, S; Wilkinson, D T

1996-01-01

319

Absolute temperature measurements using a two-color QWIP focal plane array  

Science.gov (United States)

The infrared photon flux emitted by an object depends not only on its temperature but also on a proportionality factor referred to as its emissivity. Since the latter parameter is usually not known quantitatively a priori, any temperature determination based on single-band radiometric measurements suffers from an inherent uncertainty. Recording photon fluxes in two separate spectral bands can in principle circumvent this limitation. The technique amounts to solving a system of two equations in two unknowns, namely, temperature and emissivity. The temperature derived in this manner can be considered absolute in the sense that it is independent of the emissivity, as long as that emissivity is the same in both bands. QmagiQ has previously developed a 320x256 midwave/longwave staring focal plane array which has been packaged into a dual-band laboratory camera. The camera in question constitutes a natural tool to generate simultaneous and independent emissivity maps and temperature maps of entire two-dimensional scenes, rather than at a single point on an object of interest. We describe a series of measurements we have performed on a variety of targets of different emissivities and temperatures. We examine various factors that affect the accuracy of the technique. They include the influence of the ambient radiation reflected off the target, which must be properly accounted for and subtracted from the collected signal in order to lead to the true target temperature. We also quantify the consequences of spectrally varying emissivities.

Bundas, Jason; Dennis, Richard; Patnaude, Kelly; Burrows, Douglas; Faska, Ross; Sundaram, Mani; Reisinger, Axel; Manitakos, Dan

2010-04-01

320

In-flight measurement of the absolute energy scale of the Fermi Large Area Telescope  

Science.gov (United States)

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.

Ackermann, M.; Ajello, M.; Allafort, A.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bouvier, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Casandjian, J. M.; Cecchi, C.; Charles, E.; Chekhtman, A.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Cutini, S.; de Palma, F.; Dermer, C. D.; Digel, S. W.; Do Couto E Silva, E.; Drell, P. S.; Drlica-Wagner, A.; Dubois, R.; Enoto, T.; Falletti, L.; Favuzzi, C.; Fegan, S. J.; Focke, W. B.; Fortin, P.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gehrels, N.; Germani, S.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Grove, J. E.; Guiriec, S.; Hadasch, D.; Hayashida, M.; Hays, E.; Hughes, R. E.; Jóhannesson, G.; Johnson, A. S.; Johnson, T. J.; Kamae, T.; Katagiri, H.; Kataoka, J.; Knödlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S.-H.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Madejski, G. M.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mizuno, T.; Moiseev, A. A.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nakamori, T.; Naumann-Godo, M.; Nolan, P. L.; Norris, J. P.; Nuss, E.; Ohsugi, T.; Okumura, A.; Omodei, N.; Orlando, E.; Ormes, J. F.; Ozaki, M.; Paneque, D.; Panetta, J. H.; Parent, D.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; Rochester, L. S.; Sgrò, C.; Siskind, E. J.; Smith, P. D.; Spandre, G.; Spinelli, P.; Suson, D. J.; Takahashi, H.; Tanaka, T.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Tosti, G.; Troja, E.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vilchez, N.; Vitale, V.; Waite, A. P.; Wang, P.; Winer, B. L.; Wood, K. S.; Yang, Z.; Zimmer, S.

2012-01-01

 
 
 
 
321

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

322

SQUID-based setup for the absolute measurement of the Earth’s magnetic field  

International Nuclear Information System (INIS)

We present a configuration of LTS dc SQUID magnetometers that is suited for an absolute measurement of the vector components of the Earth’s magnetic field with a white noise level of about 6 fT Hz?1/2. Due to its periodic voltage–flux characteristic, a SQUID’s output voltage generally corresponds to a set of equidistant fluxes or magnetic field strengths. To resolve this ambiguity, we introduce a configuration of coplanar SQUIDs integrated on a single chip, which exhibit effective areas differing by several orders of magnitude. The set of possible magnetic field strengths matching the output voltages of these SQUIDs is thereby significantly reduced and especially unique for magnetic field strengths less than a certain threshold value of about 10 ?T in our current implementation. The SQUIDs are realized with 0.8 ?m cross-type Josephson junctions that withstand high background fields of up to 3.9 mT during cool down and operation. A first one-dimensional experimental implementation successfully measured the modulation of the magnetic field component perpendicular to the sensor surface with amplitudes exceeding 50 ?T. The overall dynamic range of the SQUID magnetometer system achieves 190 dB. (paper)

2013-03-01

323

Measurement of the radioactivity of the channel DTD before Chernobyl  

International Nuclear Information System (INIS)

The activity concentration of long loved fission and corrosion products and natural radionuclides has been measured in a selected part of the Danube-Tisa-Danube channel system which is not receiving liquid effluents from nuclear power plants. The comparison with the activities measured in the river danube did not show statistically significant differences. The results obtained describe the reference level of radioactivity for the evaluation of the contamination of the system caused by the Chernobyl accident. (author)

1987-06-01

324

Radioactivity measurement for emergency or post-accident situations  

International Nuclear Information System (INIS)

Specific objectives have to be achieved by radioactivity measurements during emergency or post-accident situations, which are different from those in normal situation. At the beginning of a nuclear emergency, few radioactivity data will be available, mainly from automatic monitoring systems implemented on the site or in its surrounding. Progressively, measurement programmes will be performed, in priority to get information on dose rate, atmospheric radionuclides and surface activities. In order to avoid excessive exposure of the measure teams, these programmes should be optimized. During early post-accident phase, different types of measurements will be done, following two main objectives: 1) to improve the assessment of the environmental contamination and people exposure; 2) for control purpose, to check the contamination of urban places, foodstuff and other products, compared to specific reference levels. The samples measurement in laboratories would be a challenge: usually, the laboratories involved in routine monitoring have to deal with very low level of radioactivity and a poor diversity of artificial radionuclides; after a reactor accident, the environmental samples to be measured would be more active and with a mixture of radionuclides (mainly with short or middle half-life) difficult to be characterized. So theses laboratories have to be trained and organised before any severe accident. (author)

2010-06-01

325

Absolute frequency measurement for the emission transitions of molecular iodine in the 982 - 985 nm range  

International Nuclear Information System (INIS)

We report high-precision frequency measurements of the separate hyperfine structure (HFS) components of the emission B - X system transitions of 127I2 molecules in the 982 - 985 nm range. To resolve the HFS of the emission lines, advantage was taken of the method of three-level laser spectroscopy. The function of exciting radiation was fulfilled by the second harmonic of a cw Nd : YAG laser, and the probe radiation in the 968 - 998 nm range was generated by an external-cavity diode laser. The output Nd : YAG laser frequency was locked to an HFS component of the absorption transition and the probing laser radiation to the emission transition component. When both frequencies were locked to HFS components with a common upper level, the output diode laser frequency was precisely equal to the emission transition frequency. The output frequency of the thus stabilised diode laser was measured with the help of a femtosecond optical frequency synthesiser based on a Ti : sapphire laser. We present the results of the absolute frequency measurements of 20 HFS components belonging to six vibrational - rotational transitions of the B - X system of iodine [R56(32 - 48)a1, P58(32 - 48)a1, P85(33 - 48)a1, R87(33 - 48a1, R88(33 - 48)a10] and all 15 components of the R86(33 - 48) line. The relative measurement uncertainty is equal to 7×10-10 and is determined by the frequency instability of the diode laser radiation.

2012-03-31

326

Absolute frequency measurement for the emission transitions of molecular iodine in the 982 - 985 nm range  

Energy Technology Data Exchange (ETDEWEB)

We report high-precision frequency measurements of the separate hyperfine structure (HFS) components of the emission B - X system transitions of {sup 127}I{sub 2} molecules in the 982 - 985 nm range. To resolve the HFS of the emission lines, advantage was taken of the method of three-level laser spectroscopy. The function of exciting radiation was fulfilled by the second harmonic of a cw Nd : YAG laser, and the probe radiation in the 968 - 998 nm range was generated by an external-cavity diode laser. The output Nd : YAG laser frequency was locked to an HFS component of the absorption transition and the probing laser radiation to the emission transition component. When both frequencies were locked to HFS components with a common upper level, the output diode laser frequency was precisely equal to the emission transition frequency. The output frequency of the thus stabilised diode laser was measured with the help of a femtosecond optical frequency synthesiser based on a Ti : sapphire laser. We present the results of the absolute frequency measurements of 20 HFS components belonging to six vibrational - rotational transitions of the B - X system of iodine [R56(32 - 48)a1, P58(32 - 48)a1, P85(33 - 48)a1, R87(33 - 48a1, R88(33 - 48)a10] and all 15 components of the R86(33 - 48) line. The relative measurement uncertainty is equal to 7 Multiplication-Sign 10{sup -10} and is determined by the frequency instability of the diode laser radiation.

Matyugin, Yu A; Ignatovich, S M; Kuznetsov, Sergei A; Nesterenko, M I; Okhapkin, M V; Pivtsov, V S; Skvortsov, Mikhail N; Bagaev, Sergei N [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

2012-03-31

327

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)

2009-10-11

328

Evaluation of uncertainty and detection limits in radioactivity measurements  

Energy Technology Data Exchange (ETDEWEB)

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.

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

329

Physical measurements with high-energy radioactive beams  

International Nuclear Information System (INIS)

Physical measurements were made with high-energy radioactive beams (positron emitters) produced as secondary particles from a heavy-particle accelerator. Data are presented for water-equivalent thickness of a silicon diode, a comparison of Bragg peak ionization depth vs stopping depth, and differential stopping depths when a beam is intercepted by heterogeneous materials in the orthogonal direction. A special positron-emitting beam analyzing (PEBA) system was used in form images of the stopped radioactive beam. These measurements will have direct impact on charged-particle radiotherapy, since the precise range of beams of charged particles to targets within patients can be measured and used for treatment planning. Also, during the treatments the stopping point of the beam can be monitored to verify that the treatment is being delivered as planned

1982-01-01

330

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Phung, Ha; Courde, Cle?ment; Brillet, Alain; Alexandre, Christophe; Lintz, Michel

2013-01-01

331

Absolute femtosecond measurements of Auger recombination dynamics in lead sulfide quantum dots  

Directory of Open Access Journals (Sweden)

Full Text Available Multiphoton excitation of hot carriers generates multiexcitons that are probed as a function of the absolute number of photons absorbed. Standard assumptions of Auger recombination analyses fail for an average of 2 excitations.

Jonas D.M.

2013-03-01

332

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%

2005-05-01

333

Absolute neutron capture cross sections of uranium-238 by spherical shell transmission measurements  

International Nuclear Information System (INIS)

The required accuracy of capture cross sections of the fertile isotope "2"3"8U in the keV-region is 1 - 2%. In experiments is achieved 3 - 5% now, but the data have discrepancies up to 20%. An analysis of literature data at 24 and 30 keV has given average values with an uncertainty of +-10%. In a spherical shell transmission experiment in indirect geometry on the 1000 m-TOF-path of the pulsed fast reactor IBR-30 of the JINR Dubna the sphere transmission function has been measured in a wide energy range using "3He-proportional counter batteries and five shell targets. Absolute average ABBN-group capture cross sections of "2"3"8U in the energy range 215 eV to 100 keV and capture cross sections of 24 and 30 keV have been determined using Monte Carlo calculations and two different methods to consider the resonance self shielding effect. The accuracy of the data is about 5%. The results are compared with literature data and support the tendency of the less increasing capture cross section of "2"3"8U from 40 keV down to 1 keV. In this energy range they are about 10 - 20% lower than the ABBN-70 data. (author)

1977-01-01

334

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)

2007-01-01

335

C2O(X tilde 3?-): Absolute reaction rates measured by laser induced fluorescence  

International Nuclear Information System (INIS)

Absolute rate constants are reported for reactions of C2O(X tilde 3?-) under pseudo-first-order decay conditions. C2O is generated by laser photodissociation of C3O2 at 266 nm, and detected by dye-laser induced fluorescence on the A tilde 3PIsub(i)-X tilde 3?- transition. Rate constants of (433 +- 12), (3.30 +- 0.12) and (1.12 +- 0.05) x 10-13 cm3 molecule-1s-1 are reported for reactions with NO, O2 and isobutene. The NO value is approximate due to an apparent dark reaction between NO and C3O2. Upper limits of 1 x 10-14 cm3 molecule-1s-1 are reported for reactions with H2, CO2, C2H2 and C2H4. The C2O + C3O2 reaction does not follow pseudo-first-order decay kinetics. Two explanations are proposed to explain this observation. Results are compared with previous relative rate measurements and are discussed in terms of their relevance to combustion chemistry. (orig.)

1980-07-01

336

On the calibration of a superconducting gravimeter using absolute gravity measurements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A 24 hr continuous parallel registration between an absolute free-fall gravimeter and a relative cryogenic gravimeter is analysed. Different adjustment procedures (L,, L2 norms) are applied to the sets of absolute and relative readings in order to estimate the value of the calibration factor of the superconducting meter, as well as its uncertainty. In addition, a sensitivity test is performed to investigate the influence of some parameters (like the laser frequency and its short-term drift) u...

Hinderer, Jacques; Florsch, Nicolas; Ma?kinen, J.; Legros, Hilaire; Faller, J. E.

1991-01-01

337

Quality assurance programmes for radioactivity measurements in nuclear medicine  

International Nuclear Information System (INIS)

The accuracy of the estimation of dose delivered to patients receiving radiopharmaceutical therapy is vitally linked to the accuracy of measurements of the amount of radioactivity contained in the drug. This is due primarily to the fact that most Monte Carlo codes currently in use express the calculated dose in terms of a dose rate per unit activity. In order to reconcile experimental (or administered) dose rates and calculated (or intended) doses, the activity must be known as accurately as possible. Moreover, the consistency of dose estimates among a group of sites participating in clinical trials can only be ensured when the activity measurements are referenced to national or international standards. The Radioactivity Group of the National Institute of Standards and Technology (NIST) has an extremely active program aimed at ensuring good radioactivity measurements at all levels of nuclear medicine practice in North America. This talk gives an overview of this program and will conclude with a discussion of how it can be used as a model for an international effort in measurement quality assurance for nuclear medicine and radiopharmacy

2002-11-25

338

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)

1996-01-01

339

DANCE device for measurement of (n, ?) reactions on radioactive species  

International Nuclear Information System (INIS)

DANCE (Device for Advanced Neutron Capture Experiments) is a 4? 162 element BaF2 array under development at Los Alamos National Laboratory. It is designed to provide high granularity, fast timing and high photon detection efficiency. It will be located at the Los Alamos Neutron Scattering Center where neutrons are produced using 800 MeV proton induced spallation reactions on heavy element production targets. Using the pulsed high neutron fluence available at this facility combined with time of flight techniques it will be possible to make neutron capture measurements in the neutron energy range from eV to 100's keV on rate and radioactive target material at the milligram and below level. These measurements will provide critically needed data for the interpretation of the astrophysical s-process 'branching point' nuclei as well as information for reactions needed in understanding transmutation processes of radioactive species. (author)

2002-08-01

340

Measurement of absolute E2 transition strengths in 176W: Signatures for a rapid shape change  

International Nuclear Information System (INIS)

The X(5) symmetry describes nuclei at the critical point of the shape phase transition from axially deformed rotor nuclei to spherical vibrators. 150Nd, 152Sm, and 154Gd were the first nuclei where the predicted characteristics of the X(5) symmetry were observed. Later it was shown that also 176,178,180Os can be successfully described with the X(5) symmetry.In the close vicinity of shape phase transitions one expects strongly changing nuclear shapes. In the X(5) region around A = 150 this was observed for nuclei with different neutron numbers, whereas in the X(5) region around A = 180 this is to be expected for different proton numbers. The aim of the work presented here is the confirmation of a rapid shape change for nuclei close to 178Os. Besides the knowledge on the level scheme of the nuclei of interest, especially absolute E2 transition strengths are crucial for the interpretation of nuclear structure. Prolate deformation is expected for 176W. Thus we performed a recoil distance Doppler shift (RDDS) measurement on 176W to measure E2 transition strengths from level lifetimes. The experiment was performed at the Cologne FN TANDEM accelerator with the Cologne coincidence plunger with the reaction 169Dy(16O,4n)176W and a beam energy of 80 MeV. We will present our experimental results and relate them to data on the neighboring nuclei 178Os and 182Pt. The results will be discussed in the framework of nuclear shape transitions in this mass region and compared to calculations with both the Interacting Boson Model (IBM) and the GCM.

2011-10-28

 
 
 
 
341

Inner-shell transition measurements with radioactive atoms  

International Nuclear Information System (INIS)

The general principles underlying the experimental techniques that make use of radioactive isotopes for the production of primary vacancies in atomic inner shells and the study of their decay modes are outlined, and a survey is made of the current status of the results. Topics covered include: fluorescence, Auger, and Coster-Kronig yields; decay of double inner-shell vacancy states; Auger electron intensities; relative x-ray intensities; measurement of widths; and directional correlations. 13 figures, 95 references

1975-01-01

342

Measurements of radioactive dusts in high altitude air  

Energy Technology Data Exchange (ETDEWEB)

The radioactivities of the airborne dusts were measured in samples collected by an aircraft of the Japan Air Self-Defence Force in high altitude during the period between April 1997 and March 1998. The data of the gross beta activities show that there is no appreciable difference from the activity levels of the year before and seasonal variations are becoming not so clear. (author)

Endo, Hiromu; Sato, Mihoko; Harukawa, Junichi; Katoh, Michihiko; Watanabe, Kenji [Japan Defence Agency, Tokyo (Japan). First Research Center

1998-10-01

343

Low-level radioactivity measurements in an ocean shellfish matrix  

International Nuclear Information System (INIS)

Reference marine biological samples are necessary to test the performance of the analytical methods employed in surveying and monitoring radioactive materials in the sea. The measurement of artificial and natural radionuclide activity concentrations in ocean shellfish material by nondestructive ultra low-level ?-ray spectrometry in an underground laboratory is reported. The material analysed, a composite material made of Irish Sea and White Sea mussel and Japan Sea oyster, was prepared by the National Institute of Standards and Technology (NIST)

2000-03-01

344

In-situ measurements of the radioactive fallout deposit  

International Nuclear Information System (INIS)

An improved method to determine radionuclide concentrations in soil and the radioactive fallout deposit is presented. The approach is based on in-situ gamma-ray spectrometric measurements performed with a portable high-resolution gamma spectrometer and on calculations of the depth distribution based on the energy dependence of the attenuation of gamma rays in soil. The results are compared with laboratory analysis of collected soil samples. (orig.)

1991-02-01

345

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

2010-01-01

346

Precision mass measurements of radioactive nuclei at JYFLTRAP  

CERN Document Server

The Penning trap mass spectrometer JYFLTRAP was used to measure the atomic masses of radioactive nuclei with an uncertainty better than 10 keV. The atomic masses of the neutron-deficient nuclei around the N = Z line were measured to improve the understanding of the rp-process path and the SbSnTe cycle. Furthermore, the masses of the neutron-rich gallium (Z = 31) to palladium (Z = 46) nuclei have been measured. The physics impacts on the nuclear structure and the r-process paths are reviewed. A better understanding of the nuclear deformation is presented by studying the pairing energy around A = 100.

Rahaman, S; Eronen, T; Hager, U; Hakala, J; Jokinen, A; Kankainen, A; Moore, I D; Pentillä, H; Rinta-Antila, S; Rissanen, J; Saastamoinen, A; Sonoda, T; Weber, C; Äystö, J

2007-01-01

347

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

CERN Document Server

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.

Shendrik, Roman

2013-01-01

348

Absolute measurement and international intercomparison of 0.1-0.8 MeV monoenergetic neutron fluence rate  

International Nuclear Information System (INIS)

The methods for absolute measurement of 0.1-18MeV monoenergetic neutron fluence rate are described. Which include proton recoil telescope, semicoducetor telescope, hydrogen filled proportional counter and associated particale method. A long counter used as secondary recent international intercomparison of neutron fluence rate organized by BIPM, and the results were given

1988-01-01

349

Measuring method of absolute fluxes of linear X radiation of laser plasma on the Iskra-5 device  

International Nuclear Information System (INIS)

The measuring method of absolute fluxes of linear X radiation of the laser-produced plasma from targets irradiated on the device Iskra-5 is considered. The main characteristics of spectrophotometers intended for recording the linear X radiation of hydrogen- and helium-like lines of Al, Si, Ar and Fe are presented. They are based on convex and concave crystals made from quartz and mica. The techniques and results of the absolute calibration of cry stalls, X-ray photographic films and filters used in experiments are given. The methods of spectrogram processing with accounting of calibration results are considered

2005-06-13

350

The orbit of Phi Cygni measured with long-baseline optical interferometry - Component masses and absolute magnitudes  

Science.gov (United States)

The orbit of the double-lined spectroscopic binary Phi Cygni, the distance to the system, and the masses and absolute magnitudes of its components are presented via measurements with the Mar III Optical Interferometer. On the basis of a reexamination of the spectroscopic data of Rach & Herbig (1961), the values and uncertainties are adopted for the period and the projected semimajor axes from the present fit to the spectroscopic data and the values of the remaining elements from the present fit to the Mark III data. The elements of the true orbit are derived, and the masses and absolute magnitudes of the components, and the distance to the system are calculated.

Armstrong, J. T.; Hummel, C. A.; Quirrenbach, A.; Buscher, D. F.; Mozurkewich, D.; Vivekanand, M.; Simon, R. S.; Denison, C. S.; Johnston, K. J.; Pan, X.-P.

1992-01-01

351

Ultra low radioactivity measurements at Modane underground Laboratory  

International Nuclear Information System (INIS)

We present in this paper the activities of the Laboratoire Souterrain de Modane, LSM, and in particular the activity related to Single-Event Rate Errors in semiconductors. The LSM is located in the middle of the Frejus tunnel under 1 800 m of rock. The rock coverage suppress the cosmic ray flux by about 2 millions with respect to the surface, thus, the LSM offers an excellent site for rare-event searches which would, if located on the surface, be overwhelmed by the cosmic-ray background. As semiconductor devices continue to be scaled down, the integrated circuits are sensitive to interactions with cosmic-ray particles on the surface (primarily atmospheric neutrons) or to interactions with alpha-particles produced in on-chip radioactive impurities disintegrations. The ultra-low background environment at LSM allows the measurement of extremely low radioactivity levels. The aim of the work presented in this paper is to assess the feasibility of the alpha-emission measurement in materials commonly used in integrated circuits, by means of ultra-low level gamma-spectrometry. An epoxy slab has been measured and the surface ?-emission has been deduced from the radioactive impurities level. The result is compared to the value obtained with an a- gas proportional counter. (authors)

2010-03-01

352

Airborne Measurement of Radioactivity by Learjet 35 A  

International Nuclear Information System (INIS)

Full text: The Deutscher Wetterdienst (DWD, German Meteorological Service) is responsible for surveillance of radioactivity in the atmosphere. In case of an accident, radioactive plumes may be expected in high heights up to the tropopause, however it depends on the type of accident. For this reason, aircraft measurements are necessary as a supplement to ground-based measuring sites, especially in case of non available details about the source of radioactive release and lack of details about the accident. The authors present an aircraft, type Learjet 35 A, used for localising radioactive contaminated air masses up to 33,000 feet (10,000 m) and the measurement of artificial radionuclides on aerosols. For this purpose the jet is equipped with an isokinetic high-volume sampler for collection of aerosols on filters outside the pressurised cabin and an onboard gamma spectrometry system with a high purity germanium detector to analyse the interchangeable, contaminated filters during flight, as well as a dose ratemeter, a radon daughter monitor and for navigation a GPS (Global Positioning System). The collection of gaseous iodine is optional. The meteorological parameters temperature, relative humidity, wind speed and wind direction are determined as well. Resulting data are transmitted by global VHF datalink (Very High Frequency) from the plane to the DWD headquarter and used for verifying the prognosis. In case of emergency the plane has to be airborne not later than 10 hours after alert. Homebase of the Learjet is a German military airbase, 100 km northwest of Hamburg. Six backup Learjets are available. The Learjet's service ceiling is 41,000 feet (12,330 m), cruising speed 800 km/hr, max. flying time 5 hrs. Originally developed to be operated in Germany, the Learjet can reach every destination in Europe within 3 hours. (author)

2001-05-20

353

Impurezas em solucoes radioativas por espectrometria gama. (Impurities in radioactive solutions for gamma spectroscopy).  

Science.gov (United States)

The absolute and relative methods for radioactive sources calibration, like 4 (Pi)(beta)-(gamma) and 4(Pi)(gamma) ionization chamber respectively, allows to reach 0,1% of exactiness in activity measurement, but cannot distinguish radioactive impurities th...

J. U. Delgado

1990-01-01

354

Measurements of environmental radiations and radioactivities in Toki, 5  

International Nuclear Information System (INIS)

The booklet carries six reports. The first report, titled 'Measurements of Environmental Radiation in 1986 and 1987', consists of two parts: 'A report of TLD Measurement of Environmental Radiations in the Toki Area' and 'Measurement of Environmental Radiations at the Higashiyama and Toki Sites'. Measurements of environmental radiations made at various points throughout the area are presented. The second report, titled 'Environmental Tritium Measurements in Toki Area', presents measurements of environmental tritium made at various points in the Toki area. The third study addresses the 'Radioactivity in Rain Associated with Chernobyl Nuclear Reactor Accident'. Rain is collected on the roof of the Institute of Plasma Physics, and gamma ray measurements are made with a germanium detector. The concentrations of radioactive fallout substances are analyzed. Then, the relations of the concentrations with the spatial dose rate is investigated. The fourth work deals with the 'Concept and Mutual Relation of Radiation-Related Quantities'. The fifth report outlines a 'System for Radiation Monitoring around Accelerator'. The sixth report describes some features of the National Lab. for High Energy Physics (KEK). (N.K.)

1989-01-01

355

Measurements of environmental radiations and radioactivities in Toki, 6  

International Nuclear Information System (INIS)

The booklet carries five reports. The first one, titled 'A Study on Nuclear Fusion Environmental Safety in the Nagoya University, Institute of plasma physics', deals with the design and development of a radiation monitoring system and a tritium monitoring system. The second work, titled 'Measurement of Environmental Radiations', consists of two parts: 'A report on TLD Measurement of Environmental Radiations in the Toki Area' and 'TLD Measurement in Toki Area (1982-1988)'. Measurements of environmental radiations made at various points throughout the area are presented. The third study addresses 'Radioactivity in Rain Associated with Chernobyl Nuclear Reactor Accident'. Rain is collected on the roof of the Institute of Plasma Physics, and gamma ray measurements are made with a germanium detector. The concentrations of radioactive fallout substances are analyzed. Then, the relations of the concentrations with the spatial dose rate is investigated. The fourth report, titled 'Measurements of Environmental Tritium Concentration in the Toki Area', deals with measurements made at various points throughout the area are listed. The fifth and last report briefly outlines some features of the Kyoto University Plasma Physics Laboratory and the Osaka University Institute of Laser Engineering. (N.K.)

1989-01-01

356

Radioactivity  

... Radioactive isotopes of iodine, which undergo beta-decay, can build up in the thyroid gland and can cause thyroid cancer. Attempts to prevent this involve distributing pills that include nonradioactive iodine-127 and which flood the thyroid, preventing uptake of radioactive iodine. For one-off doses, ...

357

Hair radioactivity as a measure of exposure to radioisotopes  

Science.gov (United States)

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.

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

1972-01-01

358

Functional requirements document for measuring emissions of airborne radioactive materials  

International Nuclear Information System (INIS)

This document states the functional requirements and procedures for systems making measurements of radioactive airborne emissions from facilities at the Hanford Site. The following issues are addressed in this document: Definition of the program objectives; Selection of the overall approach to collecting the samples; Sampling equipment design; Sampling equipment maintenance, and quality assurance issues. 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

1994-01-01

359

A study of environmental radioactivity measurements for Cankiri, Turkey.  

Science.gov (United States)

This study is the first to assess the level of background radiation for the Cankiri province of Turkey. Indoor air radon concentrations were determined using Columbia Resin-39 nuclear track detectors and the average (222)Rn activity was found to be 44 Bq m(-3) (equivalent to an annual effective dose of 1.1 mSv). Measurements of gamma doses in outdoor air were performed using a portable plastic scintillation detector and the average gamma absorbed dose rate was found to be 8 ?R h(-1) (corresponding to an annual effective dose of 87.7 ?Sv). Radionuclide activity concentrations in soil samples were measured through gamma-ray spectrometry and the average activities were determined as 17.7, 22.3, 357 and 4.1 Bq kg(-1) for the radionuclides (238)U, (232)Th, (40)K and (137)Cs, respectively. The average annual effective dose from the natural radioactivity sources ((238)U series, (232)Th series and (40)K) was calculated to be 44.4 ?Sv. Radioactivity levels of drinking water samples were carried out using a low-background proportional counter and the average gross alpha and beta activities were obtained as 0.25 and 0.26 Bq l(-1), respectively (equivalent to an annual effective dose of 184 ?Sv). The average radon concentrations in indoor air and the average radionuclide activities in soil were found to be lower than most Turkish cities while higher levels of outdoor gamma dose rate and water radioactivity were observed. The results of this study showed that the region's background radioactivity level differs considerably from the reported data for Turkish cities. PMID:22069234

Kapdan, Enis; Taskin, Halim; Kam, Erol; Osmanlioglu, A Erdal; Karahan, Gursel; Bozkurt, Ahmet

2012-07-01

360

Measurement of absolute fluorescence quantum yield of basic fuchsin solution using a dual-beam thermal lens technique.  

Science.gov (United States)

The dual beam thermal lens technique is an effective method for the measurement of fluorescence quantum yield of dye solutions. The concentration-dependent quantum yield of a novel dye of triaminotriphenylmethane family in ethanol is studied using this technique. The absolute fluorescence quantum yield is measured and is observed that the reduction in the quantum yield is due to the non-radiative relaxation of the absorbed energy. PMID:24610515

Pathrose, Bini; Nampoori, V P N; Radhakrishnan, P; Mujeeb, A

2014-05-01

 
 
 
 
361

Absolute wave-number measurements in 130Te2: reference lines spanning the 420.9-464.6-nm region  

International Nuclear Information System (INIS)

We have measured the absolute wave numbers of 39 transitions of 130Te2 spanning the spectral region of 420.9-464.6 nm to an accuracy of better than 2 parts in 109 by use of saturation spectroscopy and Fabry-Perot interferometry. These measurements provide a set of convenient and accurate transfer standards for laser wavelength calibration spanning the entire Stilbene-420 dye-tuning curve

2005-05-01

362

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)

1982-01-01

363

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

2004-01-01

364

Weak Interaction Measurements with Optically Trapped Radioactive Atoms  

International Nuclear Information System (INIS)

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project is to apply the latest in magneto-optical and pure magnetic trapping technology to concentrate, cool, confine, and polarize radioactive atoms for precise electroweak interaction measurements. In particular, the authors have concentrated their efforts on the trapping of 82Rb for a parity-violating, beta-asymmetry measurement. Progress has been made in successfully trapping of up to 6 million 82Rb(t1/2=75s) atoms in a magneto-optical trap coupled to a mass separator. This represents a two order of magnitude improvement in the number trapped radioactive atoms over all previous work. They have also measured the atomic hyperfine structure of 82Rb and demonstrated the MOT-to-MOT transfer and accumulation of atoms in a second trap. Finally, they have constructed and tested a time-orbiting-potential magnetic trap that will serve as a rotating beacon of spin-polarized nuclei and a beta-telescope detection system. Prototype experiments are now underway with the initial goal of making a 1% measurements of the beta-asymmetry parameter A which would match the world's best measurements

1999-01-01

365

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

1993-01-01

366

Measurements of the Temperature of Plasmas in MHD Ducts and Combustion Chambers by Recording Absolute Spectral Line Intensities  

International Nuclear Information System (INIS)

This work has been carried out under a collaboration agreement between the Institute of Nuclear Research, Swierk, Poland, and CEN de Saclay, France. The author discusses the theory of measuring the temperature of plasmas in combustion chambers and MHD ducts by recording the absolute intensities (AI) of spectral lines. The accuracy of the method and its suitability for measuring the temperature of plasmas in MHD ducts is analysed. The paper describes the experimental set-up, which consists of a combustion chamber and an MHD duct, and presents a schematic diagram for temperature measurements by the absolute line intensity method. The paper also describes how the accuracy of the method is checked by determining the normalized coefficient of emission of the recorded Na15890 Å and Na1 5896 Å line values. A schematic diagram is also given for measuring the surface temperature of electrodes in an MHD duct through the plasma by means of an optical pyrometer. The author presents the results of plasma temperature measurements made by the absolute line intensity method and the results of electrode surface temperature measurements for different regimes of combustion chamber operation. (author)

1968-11-01

367

Simultaneous measurement of absolute strain and differential strain based on fiber Bragg grating Fabry-Perot sensor  

Science.gov (United States)

We present a fiber Bragg grating Fabry-Perot (FBG-FP) sensor using the fast Fourier transform (FFT) demodulation for measuring the absolute strain and differential strain simultaneously. The amplitude and phase characteristics of Fourier transform spectrum have been studied. The relation between the amplitude of Fourier spectrum and the differential strain has been presented. We fabricate the fiber grating FP cavity sensor, and carry out the experiment on the measurement of absolute strain and differential strain. Experimental results verify the demodulation method, and show that this sensor has a good accuracy in the scope of measurement. The demodulating method can expand the number of multiplexed sensors combining with wavelength division multiplexing and time division multiplexing.

Wang, Kuiru; Wang, Bo; Yan, Binbin; Sang, Xinzhu; Yuan, Jinhui; Peng, Gang-Ding

2013-10-01

368

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)

2006-01-01

369

The radioactivity measurements in soil, coal and water in south Marmara region of Turkey  

Energy Technology Data Exchange (ETDEWEB)

Radioactivity levels were determined in soil, coal and water samples collected from various locations in the south Marmara region of Turkey. The activities in samples were determined using TENNELEC LB 1000-PW detector. The absolute {beta} activities were observed to vary in the range 0.83 {+-} 0.06-0.50 {+-} 0.05 for soil in units of Bq g{sup -1}, and 1.284 {+-} 0.02-0.079 {+-} 0.002 for coal samples in units of Bq g{sup -1} and 0.74 {+-} 0.05-0.06 {+-} 0.02 for water in units of Bq l(-1) . In addition, gamma spectra of soil and coal samples which have highest level of {beta} activities were measured by using HpGe detector. U-235, Pb-214, Cs-134, Cs-137, Bi-214 and K-40 were detected in soil samples. U-235, Pb-214, Cs-134 and Bi-214 were detected in coal samples. The radioactivity levels in water samples were compared with WHO and ITS recommended levels and the literature values.

Yalcin, S.; Gurler, O. [Kastamonu University, Kastamonu (Turkey). Faculty of Education

2007-02-15

370

Absolute frequency measurement of the neutral 40Ca optical frequency standard at 657 nm based on microkelvin atoms  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We report an absolute frequency measurement of the optical clock transition at 657 nm in 40Ca with a relative uncertainty of 7.5 x 10-15 , one of the most accurate frequency measurements of a neutral atom optical transition to date. The frequency (455986240494135.8 ± 3.4) Hz was measured by stabilizing a diode laser system to a spectroscopic signal derived from an ensemble of 106 atoms cooled in two stages to a temperature of 10 flK. The measurement used a femtosecond-laser-based frequency c...

Wilpers, Guido; Oates, Chris; Diddams, Scott A.; Bartels, Albrecht; Fortier, Tara M.; Oskay, Windell; Bergquist, James C.; Jefferts, Steven; Heavner, Tom; Parker, Thomas; Hollberg, Leo

2007-01-01

371

Aerial measurements of radioactivity and meteorological parameters in real time  

International Nuclear Information System (INIS)

The aircrafts operating in the case of nuclear accidents have to be equipped with all necessary instruments for radioactivity, aerosol and gas sampling, chemical characterization and additional avionic for exact flight path recordings. In close cooperation with NIR, AERODATA, FAG and FhG-IFU will provide the research aircraft Beechcraft King Air 200 and/or Hawker Siddeley 125. Impactors and denuders are to be installed on the aircraft for particle and gaseous measurements. The aircraft should be made available in stand-by operation

1989-12-05

372

Standard cartridges used in gamma spectrometry measurements of radioactive halogens  

International Nuclear Information System (INIS)

Activated charcoal cartridges are used to trap radioactive halogens contained in gaseous effluents of nuclear facilities. Two types of standard cartridges, with barium 133 or europium 152 are available. One of the models simulates a volumic distribution, and the other a surface distribution of the radionuclides inside the cartridge. They are characterized in terms of activity with an uncertainty lower than 5 %. The standard cartridges utilization conditions are specified and the main measurement error causes are analyzed. The proper routine use of these standards should allow us to get results with an accuracy better than 10 %

1988-01-01

373

The BiPo detector for ultralow radioactivity measurements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The BiPo project is dedicated to the measurement of extremely low radioactivity contamination of SuperNEMO source foils (^{208}Tl < 2 \\muBq/kg and ^{214}Bi < 10 \\muBq/kg). The R&D phase is started: a modular BiPo prototype with its shielding test facility is under construction. The goal of this prototype is to study the background and particularly the surface contamination of scintillators. The first capsule has been installed in the Canfranc Underground Laboratory in Octobe...

Lal, M. Bongrand -.

2007-01-01

374

Direct measurements of neutron capture on radioactive isotopes  

CERN Document Server

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.

Couture, A

2009-01-01

375

Whole-body radioactivity measurements at Hammersmith Hospital  

International Nuclear Information System (INIS)

Three people who had been in Eastern Poland or Scandinavia at the time of the accident were referred to the Medical Physics Department of the Hammersmith Hospital for checks of their thyroidal content of "1"3"1I. The opportunity was taken to measure their body content of "1"3"1I also and to assess their contamination by other fission products. A few samples of milk and water collected in Scotland soon after the radioactive cloud had passed over were also monitored. (author)

1986-01-01

376

Radioactive ion implantation as a tool for wear measurements  

International Nuclear Information System (INIS)

The present paper deals with ion implantation of radioactive krypton ions in surfaces with aim of measuring wear of different magnetic materials in sound-heads. The technique is especially suited for a relatively fast comparison of wear-characteristics of materials of varying composition in small inaccessible areas. In the present case utilisation of a 60 KeV accelerator allows determination of a total wear as small as 0.05 ?m with an accuracy of 10%. Further the technique yields information of the time dependence of the wear process with an accuracy less than 0.001 ?m. (author)

1979-01-04

377

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

1998-07-01

378

Broad band and absolute measurement of transient dynamic normal velocity of surface  

Science.gov (United States)

Broad band direct sensing of the transient dynamic normal velocity of an object surface and evaluating its absolute value were realized by using a sensor fabricated with a piezoelectric polyvinylidene fluoride film and a polyvinyl chloride (PVC) back load and a PVC wear plate. The transient output signal from the sensor obtained by a test employing a well-defined steplike force, at the epicenter of a steel plate, showed very good agreement with the dynamic normal velocity calculated by using a Green's function and a simulated source function. The output was proportional to the dynamic normal velocity of the surface, and the frequency-dependent sensitivity for the velocity was flat within a deviation of +/-3.8 dB for the average in the frequency range up to 2 MHz. The transient dynamic normal velocity of the surface could be absolutely determined by using a sensor calibrated by theoretical one.

Kim, Byoung-Geuk; Enoki, Manabu; Kishi, Teruo

1998-02-01

379

Radon natural radioactivity measurements for evaluation of primary pollutants.  

Science.gov (United States)

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

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

2013-01-01

380

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

International Nuclear Information System (INIS)

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

2002-02-01

 
 
 
 
381

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

CERN Document Server

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

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

2002-01-01

382

Radioactivity measurements in the vicinity of Swiss nuclear power plants  

International Nuclear Information System (INIS)

To determine the radionuclide concentration in soil and on soil surface, respectively, caused by radionuclide releases from nuclear power plants, field gamma spectrometry is used to obtain, in a short period of time, quantitative data about the environmental radiation field, natural or man-made. This is obviously difficult to achieve by conventional sampling methods and laboratory analysis. This word describes the instruments used and the calibration methods, and gives the results of in situ measurements made around the Swiss nuclear power plants. The measurements and computations are compared with a laboratory analysis of collected soil samples and with total exposure rate measurements in air. In addition to natural radioactivity this method allows especially the detection of radionuclides released from nuclear power stations to the environment with a good sensitivity. (orig.)

1986-01-01

383

Radioactive waste reality as revealed by neutron measurements  

Energy Technology Data Exchange (ETDEWEB)

To comprehend certain aspects of the contents of a radioactive waste container is not a trivial matter, especially if one is not allowed to open the container and peer inside. One of the suite of tools available to a practioner in the art of nondestructive assay is based upon neutron measurements. Neutrons, both naturally occuring and induced, are penertrating radiations that can be detected external to the waste container. The practioner should be skilled in applying the proper technique(s) to selected waste types. Available techniques include active and passive neutron measurements, each with their own strengths and weaknesses. The waste material itself can compromise the assay results by occluding a portion of the mass of fissile material present, or by multiplying the number of neutrons produced by a spontaneously fissioning mass. This paper will discuss the difficult, but albeit necessary marriage, between radiioactive waste types and alternative neutron measurement techniques.

Schultz, F.J. [Oak Ridge National Lab., TN (United States)

1995-12-31

384

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

2001-12-01

385

Application of a time-correlated associated particle method for absolute cross-section measurements of heavy nuclides  

Energy Technology Data Exchange (ETDEWEB)

The joint fission cross-section measurements program of the V. G. Khlopin Radium Institute and the Technical University of Dresden is described. The errors and uncertainties of the time correlated associated particle method of fission cross-section measurements for 2.6, 8.5, and 14.7-MeV neutrons are discussed. Experimental results of absolute fission cross-section measurements of /sup 235/U, /sup 238/U, /sup 237/Np, and /sup 239/Pu for 14.7 MeV-neutrons and of /sup 235/U for 2.6 and 8.2-MeV neutrons are given.

Arlt, R. (Technical Univ. of Dresden, Germany); Grimm, W.; Josch, M.

1980-09-01

386

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

1987-01-26

387

Calibration of Marinelli vessels for measurement of radioactive environmental samples  

International Nuclear Information System (INIS)

In order to measure low-activity radioactive environmental samples, both in liquid and solid phases, the use of Marinelli (reentrant) beakers is recommended. Standards were prepared by mixing of standardized radioactive solutions with CaCO3 of density 1.1 to 1.3 g cm-3, similar to densities of environmental samples. Measurements of calibrated Marinelli comparator standards on detector surface showed that the dependence of log Eff vs. log E is almost linear in the 120 keV to 1500 keV range. The data can be fitted more accurately by assuming a parabolic correlation (log Eff vs. log E). The validity of these standards was checked by determining the concentration of radio-europium, radio-cesium and 226Ra in three certified reference standard materials. The results obtained agreed well with the published certified data. The limit of detection for the determination of radio-cesium by ?-ray spectrometry under the prevailing experimental conditions is 0.1 Bq (2.7 pCi), for 0.5 kg of environmental samples. (orig.)

1997-01-21

388

Calibration of Marinelli vessels for measurement of radioactive environmental samples  

Energy Technology Data Exchange (ETDEWEB)

In order to measure low-activity radioactive environmental samples, both in liquid and solid phases, the use of Marinelli (reentrant) beakers is recommended. Standards were prepared by mixing of standardized radioactive solutions with CaCO{sub 3} of density 1.1 to 1.3 g cm{sup -3}, similar to densities of environmental samples. Measurements of calibrated Marinelli comparator standards on detector surface showed that the dependence of log Eff vs. log E is almost linear in the 120 keV to 1500 keV range. The data can be fitted more accurately by assuming a parabolic correlation (log Eff vs. log E). The validity of these standards was checked by determining the concentration of radio-europium, radio-cesium and {sup 226}Ra in three certified reference standard materials. The results obtained agreed well with the published certified data. The limit of detection for the determination of radio-cesium by {gamma}-ray spectrometry under the prevailing experimental conditions is 0.1 Bq (2.7 pCi), for 0.5 kg of environmental samples. (orig.).

Lavi, N. [Tel Aviv Univ. (Israel). Inst. for Environ. Res.; Alfassi, Z.B. [Ben-Gurion Univ. of the Negev, Beer Sheva (Israel); Drndarski, N. [Inst. of Nuclear Sciences - Vinca, Belgrad (Yugoslavia)

1997-01-21

389

Absolute nuclear material assay  

Science.gov (United States)

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.

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

2012-05-15

390

Quality assurance for radioactive measurement in nuclear medicine  

International Nuclear Information System (INIS)

The field of nuclear medicine continues to grow around the world, owing in part to a number of successful programmes carried out by the IAEA to enhance the use of nuclear medicine techniques in Member States. The implementation of quality assurance (QA) programmes to ensure the safe application of radiopharmaceuticals has, however, been variable in many Member States. One possible reason is the lack of a unified set of principles regarding the establishment of such programmes. This publication addresses the issue of QA programmes for radioactivity measurement in nuclear medicine. A group of experts consulted by the IAEA recommended in 2002 that unified principles concerning QA and quality control (QC) procedures for the measurement of radioactivity in nuclear medicine be developed because of its importance in controlling the safety and effectiveness of the use of radiopharmaceuticals. This publication is the result of advice provided to the IAEA by experts in the fields of radionuclide metrology, medical physics and radiopharmacy. This report can be considered to be a more detailed and updated version of IAEA-TECDOC-602, Quality Control of Nuclear Medicine Instruments, published in 1991. Advances in the field of nuclear instrumentation since that report was published, particularly in imaging, and the increased emphasis on QA and QC prompted the need for an update. Moreover, it was realized that the activity measurement and imaging aspects had each become so specialized as to be better treated in separate publications. The present report focuses on the factors affecting radioactivity measurement and the implementation of QA and QC programmes to ensure accurate and consistent results. The IAEA has developed a safety standard on The Management System for Facilities and Activities (IAEA Safety Standards Series No. GS-R-3), which replaces the IAEA publications on QA issued as Safety Series No. 50-C/SG-Q (1996). In GS-R-3, the management system is described as a set of interrelated or interacting elements for establishing policies and objectives and enabling the objectives to be achieved in a safe and efficient way. The management system is designed to fulfil requirements that integrate elements related to safety, health, the environment, security, quality and economics. Safety is the fundamental principle upon which the management system is based. It is also recognized in GS-R-3 that QC and QA are important components of the management system. While QC is a means of applying controls to ensure that the product or service consistently meets specifications, QA is an interdisciplinary management tool that provides a means for ensuring that all work is adequately planned, correctly performed and assessed. A QA programme is designed primarily to ensure the quality of a product for a customer and may be appropriate to control the activities in radioactivity measurement in nuclear medicine. However, it would be more effective if these QA controls were integrated into a single management system. There are numerous processes that review and assess financial and technical performance, the achievement of goals and the effectiveness of an organization's processes. It is necessary to integrate the results of all assessment activities to focus decision making on the needs of the business strategy. It is important to understand how assessments enable managers to achieve higher standards of performance. The principles in this publication are based on those described in IAEA Safety Standards Series No. GS-R-3 and in the General Requirements for the Competence of Testing and Calibration Laboratories (ISO/IEC 17025:1999), which set requirements that testing and calibration laboratories must meet to demonstrate that they have a management system in place and are technically competent. The present report provides information specific to implementing these standards at both the end user (clinic) and the secondary standards radioactivity laboratory levels. If adopted to their greatest extent, the principles herein will provide the user with al l th

2006-11-01

391

Dose rate measurements around consignments of radioactive material  

International Nuclear Information System (INIS)

The International Atomic Energy Agency's (IAEA) Regulations for the Safe Transport of Radioactive Material require compliance with various radiation protection control measures and also require the competent authority to arrange for periodic assessments of the radiation doses to workers and to members of the public. It is a two-fold approach of controls and assessments. Periodic reviews of the radiological impact arising from the transport of radioactive materials by road, rail, sea and air, have been undertaken by NRPB on behalf of the UK Competent Authority. Dose assessments were made using estimated exposure times together with measured and extrapolated dose rates from 'near-field' regions close to consignments, 'mid-field' regions occupied by transiently exposed persons and 'far-field' regions occupied by members of the public. The results show that annual doses to workers and public are generally small fractions of dose limits. The exception is a small group of driver/handlers involved with packages for medical and industrial use. Compliance with the Regulations has ensured that a sufficient degree of control exists. Originally, most packages were small compared with the distances to exposed persons. Point source geometry was therefore used. More recently, it has been estimated that only a minority of all consignments of radioactive material is of sufficiently small dimensions for point source geometry to continue to apply. Instead, initial despatches of radionuclide packages can consist of consignments of several cubic metres in size, and only at tertiary despatch level would point source geometry prevail. However, for all physically large loads, the measured dose rates do not decline as rapidly as point source geometry would suggest based on the Tl value. Development of the methodology adopted by the IAEA Regulations over some 40 years has introduced parameters to compensate in part for these levels of dose rate, and, together with operational improvements in transport procedures and practices, have ensured that annual doses remain low, well below dose limits. The methodologies employed for Regulatory control measures and those for assessment of annual doses, differ with the former based on robust and conservative models. For dose assessment purposes, realistic data are used based on measured dose rates and exposure times. (author)

1999-11-02

392

Absolute left ventricular volume by a non-invasive esophageal transmission measurement  

International Nuclear Information System (INIS)

A new method for determining absolute left ventricular volumes during routine clinical gated blood pool imaging is presented. The technique is geometry independent and is the first of its kind to correct for tissue attenuation by utilizing an in vivo point source. An orally administered gelatin capsule containing Tc-99m is used for this purpose. Serial images are obtained as the capsule transits the esophagus. The transmission factor is then determined by dividing the capsule count rate in the region of the left ventricle by the capsule counts recorded in air prior to administration. Thus, experimentally determined transmission factors are directly determined for each patient

1982-09-02

393

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)

1961-10-01

394

Standardisation of 125I using seven techniques for radioactivity measurement  

International Nuclear Information System (INIS)

Seven methods of radioactivity measurement were used to standardise an 125I solution within the frame of an international key comparison organised by BIPM: photon-photon coincidence counting with two NaI detectors, photon sum-peak counting in a NaI well detector and in a 4? CsI(Tl) sandwich spectrometer, total emission counting in a windowless 4? CsI(Tl) sandwich spectrometer, electron-X,? coincidence counting and electron-X,? sum counting in a pressurised proportional counter inside a NaI well detector and liquid scintillation counting with the CIEMAT/NIST method. The solid sources were prepared by quantitative drop deposition with addition of AgNO3. The measurement methods, the results and the applied corrections are described and discussed

2005-06-01

395

Determination of intake radioactivity by ?(HPGe)-?(HPGe) coincidence measurement  

International Nuclear Information System (INIS)

It is important to estimate internal exposure dose from intake radioactivity measured by human counter. The previous paper described application of the ?-? coincidence method to human counter using two large HPGe detectors and showed equation to calculate activity without determination of ?-ray detection efficiency. This paper showed the results of further experiments using absorbers based on the previous fundamental experiments. When absorption of ?-rays in human body was simulated by depth of water on the source, the activities obtained for various depth agreed with true activity within ±10%. Furthermore, a moving source like a human in X-ray CT apparatus was measured to simulate whole body counting and the result showed usefulness of this method for human counter. (author)

2003-03-01

396

Radioactive tracer measuring methods and its applications on environmental technique  

International Nuclear Information System (INIS)

A new tracer technique for measuring reairing of recipients during discharge of biological and chemical wastes. The new technique makes possible a selective determination of oxygen originating from the atmosphere. Kr-85 have been used as gas tracer and Br-82 as tracer for measuring dilution. 2. Methods for labelling sewege with radioactive tracers have been developed. The methods may be used to study the function and effectiveness of treatment of sewage from municipolities and industries. 3. Water transport in the ground in connection with leaching from municipal dumps or sludge stocks have been studied with tracer techniques. The investigation showed that the transport of water through garbage stocks was much faster than was earlier presumed. (K.K.)

1975-01-01

397

Diagnostic measures and therapeutic possibilities in incorporations of radioactive substances  

International Nuclear Information System (INIS)

In the interest of better understanding the diagnostic measures to be taken in cases of incorporation, the exposure pathways of an incorporation are outlined and their physical and chemical mechanisms described. Attention is drawn to the need for interdisciplinary cooperation with health physics. Therapeutic possibilities are indicated for both first aid measures and further treatment by the authorized physician. These efforts are intended to reduce the absorption of the radionuclide from the gastro-intestinal tract, prevent the ascension of activity from a wound deposit to the transfer compartiment, and impede depostions of the radioactive substance in some organs. In-house experience accumulated in the treatment of incorporation accidents associated with transuranium isotopes is described on the basis of some case reports. (orig.)

1991-01-01

398

Natural radioactivity measurements of building materials in Baotou, China  

International Nuclear Information System (INIS)

Natural radioactivity due to 226Ra, 232Th and 40K in the common building materials collected from Baotou city of Inner Mongolia, China was measured using gamma-ray spectrometry. The radiation hazard of the studied building materials was estimated by the radium equivalent activity (Raeq), internal hazard index (Hin) and annual effective dose (AED). The concentrations of the natural radionuclides and Raeq in the studied samples were compared with the corresponding results of other countries. The Raeq values of the building materials are below the internationally accepted values (370 Bq kg-1). The values of Hin in all studied building materials are less than unity. The AEDs of all measured building materials are at an acceptable level. (authors)

2012-01-01

399

The BiPo detector for ultralow radioactivity measurements  

CERN Document Server

The BiPo project is dedicated to the measurement of extremely low radioactivity contamination of SuperNEMO source foils (^{208}Tl < 2 \\muBq/kg and ^{214}Bi < 10 \\muBq/kg). The R&D phase is started: a modular BiPo prototype with its shielding test facility is under construction. The goal of this prototype is to study the background and particularly the surface contamination of scintillators. The first capsule has been installed in the Canfranc Underground Laboratory in October, 17th and is now taking data. After 10.7 days of measurements, a preliminary upper limit on the surface radiopurity of the scintillators of A(^{208}Tl) < 60 \\muBq/m^2 (90% C. L.) has been obtained.

Bongrand, M

2007-01-01

400

Low level radioactivity measurement in support of the CTBTO  

International Nuclear Information System (INIS)

Radioactivity measurements, together with three other technologies: seismic, hydroacoustic and infrasound, are able to detect, identify and locate nuclear explosions down to 1 kt. Eighty stations worldwide, with a sensitivity of 10-30 ?Bq/m3 for 140Ba and 1 mBq/m m3 for 133Xe, have been or will be established in order to provide an estimated 90% detection probability within 10 days after a nuclear explosion. The equipment for manual stations - the high volume samplers, high sensitivity HPGe detectors and auxiliary measurement systems, as well as the automatic stations are described. The problems and results of atmospheric transport, site location as well as equipment and station operation are discussed

2000-07-15

 
 
 
 
401

Measurements and interpretation of indoor aerosol radioactivity by a microcomputer system  

International Nuclear Information System (INIS)

Airborne radioactivity is closely related to the aerosol concentration, which determines the radioactivity attachment. The radioactivity hazard assessment in situations where there is mixed ventilation and aerosol concentrations also requires sensitive methods for radioactivity detection. In the present study a continuously operating cassette system with a low pressure capillary impaction (Raunemaa et al., 1984) is applied to the radioactivity control. The observed radioactivity variations indoors are interpreted on the basis of particle concentration measurements as well as radon daughter attachment modelling (Raunemaa and Hautojaervi, 1984; Olin et al., 1985). (author)

1986-06-01

402

Studies of radioactivity produced by the Hiroshima atomic bomb, 2; Measurements of fallout radioactivity  

Energy Technology Data Exchange (ETDEWEB)

Three studies of fallout measurements were reviewed for the discussion of possible radioactivity intake from the Hiroshima atomic bomb. The first study discussed correlations between enriched {sup 234}U and {sup 137}Cs specific activities from the measurement of soil samples collected in the 'black rain' area. The second study measured {sup 137}Cs activity on the rock and roof tile samples collected in the hypocenter area immediately after the explosion. Some of the rock and roof tile samples collected near the hypocenter had a small but detectable amount of {sup 137}Cs activity. However, it has been determined that {sup 137}Cs exposure, for example, was negligible compared with DS86 dose estimates, since these activity levels were low. The third study detected {sup 90}Sr activity in some of the specimens of human bones exhumed on Ninoshima Island. This study compared the difference in activity between the bone head and shaft, with higher activities obtained in the bone head. This fact suggests a short intake period for this activity, however, the levels of {sup 90}Sr contamination were too low to allow a discussion of the exposure risks. (author).

Hasai, Hiromi (Hiroshima Univ., Higashi-Hiroshima (Japan). Faculty of Engineering); Hoshi, Masaharu; Yokoro, Kenjiro

1991-03-01

403

Radioactivity  

Energy Technology Data Exchange (ETDEWEB)

This item, from the Department of the Environment`s 1995 edition of the Digest of Environmental Statistics, provides information on the radiation exposure of the population from natural sources. Data is also drawn together on exposure of the public to artificial radiation, and on the discharge and disposal of radioactive wastes from nuclear facilities. (UK).

Anon.

1995-10-01

404

Changing methodology for measuring airborne radioactive discharges from nuclear facilities  

International Nuclear Information System (INIS)

The US Environmental Protection Agency (USEPA) requires that measurements of airborne radioactive discharges from nuclear facilities be performed following outdated methods contained in the American National Standards Institute (ANSI) N13.1-1969 Guide to Sampling Airborne Radioactive Materials in Nuclear Facilities. Improved methods are being introduced via two paths. First, the ANSI standard is being revised, and second, EPA's equivalency granting process is being used to implement new technology on a case-by-case or broad basis. The ANSI standard is being revised by a working group under the auspices of the Health Physics Society Standards Committee. The revised standard includes updated methods based on current technology and a performance-based approach to design. The performance-based standard will present new challenges, especially in the area of performance validation. Progress in revising the standard is discussed. The US Department of Energy recently received approval from the USEPA for an alternate approach to complying with air-sampling regulations. The alternate approach is similar to the revised ANSI standard. New design tools include new types of sample extraction probes and a model for estimating line-losses for particles and radioiodine. Wind tunnel tests are being performed on various sample extraction probes for use at small stacks. The data show that single-point sampling probes are superior to ANSI-Nl3.1-1969 style multiple-point sample extraction probes

1995-05-10

405

Changing methodology for measuring airborne radioactive discharges from nuclear facilities  

Energy Technology Data Exchange (ETDEWEB)

The US Environmental Protection Agency (USEPA) requires that measurements of airborne radioactive discharges from nuclear facilities be performed following outdated methods contained in the American National Standards Institute (ANSI) N13.1-1969 Guide to Sampling Airborne Radioactive Materials in Nuclear Facilities. Improved methods are being introduced via two paths. First, the ANSI standard is being revised, and second, EPA`s equivalency granting process is being used to implement new technology on a case-by-case or broad basis. The ANSI standard is being revised by a working group under the auspices of the Health Physics Society Standards Committee. The revised standard includes updated methods based on current technology and a performance-based approach to design. The performance-based standard will present new challenges, especially in the area of performance validation. Progress in revising the standard is discussed. The US Department of Energy recently received approval from the USEPA for an alternate approach to complying with air-sampling regulations. The alternate approach is similar to the revised ANSI standard. New design tools include new types of sample extraction probes and a model for estimating line-losses for particles and radioiodine. Wind tunnel tests are being performed on various sample extraction probes for use at small stacks. The data show that single-point sampling probes are superior to ANSI-Nl3.1-1969 style multiple-point sample extraction probes.

Glissmeyer, J.A.; Ligotke, M.W.

1995-05-01

406

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.)

2006-05-15

407

The measurement of the radioactive aerosol diameter by position sensitive semiconductor detectors, 2  

International Nuclear Information System (INIS)

Determination of the diameter of radioactive aerosol is performed by using checkerboad type position sensitive semiconductor detectors (PSD). The filter paper with the radioactive aerosols is contacted to the PSD in order to calculate the diameter of the aerosol from the measured radioactivity. (author)

1979-01-01

408

Crossed beam measurement of absolute cross sections: an alternative method and its application to the electron impact ionisation of He+  

International Nuclear Information System (INIS)

A new experimental method is reported for the crossed beam measurement of absolute cross sections. It essentially consists in sweeping one of the beams across the other in a linear 'see-saw' motion. The method is applied to one case of electron-ion collisions. A description is given of an electron gun designed to realise a linear and distortionless motion of a ribbon electron beam. Measurements are reported regarding the electron impact ionisation of He+ in the energy range 55-74 eV. (author)

1981-01-14

409

Validation study of a new technique for absolute activity measurement with 4? solid angle metallic magnetic calorimeters  

International Nuclear Information System (INIS)

In this paper we present a prototype of a new class of detectors, metallic magnetic calorimeters operating at cryogenic temperatures, which we are developing for absolute activity measurement of low-energy-emitting radionuclides. We explain the detection principle and give a detailed description of the realisation of the prototype, containing an 55Fe source inside the detector absorber. The analysis of first data taken with this detector is presented and the result of activity measurement compared with liquid scintillation counting. Some ways for reducing the uncertainty that can be achieved with this new technique are proposed

2007-09-03

410

Gas-phase NMR measurements, absolute shielding scales, and magnetic dipole moments of 29Si and 73Ge nuclei.  

Science.gov (United States)

New gas-phase NMR measurements of the shielding constants of 29Si, 73Ge, and 1H nuclei in SiH4 and GeH4 are reported. The results, extrapolated to zero density, provide accurate isolated molecule values, best suited for comparison with theoretical calculations. Using the recent ab initio results for these molecules and the measured chemical shifts, we determine the absolute shielding scales for 29Si and 73Ge. This allows us to provide new values of the nuclear magnetic dipole moments for these two nuclei; in addition, we examine the dipole moments of 13C and 119Sn. PMID:17020257

Makulski, W; Jackowski, K; Antusek, A; Jaszu?ski, M

2006-10-12

411

Absolute and relative dose measurements with Gafchromic EBT film for high energy electron beams with different doses per pulse.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The authors have evaluated the accuracy, in absolute and relative dose measurements, of the Gafchromic EBT film in pulsed high-energy electron beams. Typically, the electron beams used in radiotherapy have a dose-per-pulse value of less than 0.1 mGy/pulse. However, very high dose-per-pulse electron beams are employed in certain linear accelerators dedicated to intraoperatory radiation therapy (IORT). In this study, the absorbed dose measurements with Gafchromic EBT in both low (less than 0.3 ...

2008-01-01

412

Radioactive versus capacitance techniques for measuring soil water  

International Nuclear Information System (INIS)

A field study was conducted to compared a capacitance probe and a neutron probe for use in measuring the soil water changes and the absolute values of soil water. The study was conducted using three plots each receiving different amounts of water by a surface drip irrigation system. The 50 mm PVC access tubes were installed using a machine to auger the holes. One hole was dug using a 50 mm bulk density probe and the remaining two holes were dug using a 54 mm soil sampling tube. The two probes were calibrated to this site. The capacitance probe measured both absorption and desorption of the soil water in the semi-dry site as well as the neutron probe. The capacitance probe gave slightly higher soil water values in the semi-dry plot than the neutron probe. However, both instruments tracked the changes reasonably well. In the wet site, both probes underpredicted the actual water content, but still tracked the changes. In the dry site, which had a poorly install access tube, the capacitance probe did not accurately predict the water content or changes, while the neutron probe did. The capacitance technique will provide acceptable soil water measurements if the access tube is properly installed and appropriate calibration used. (author). 4 refs, 4 figs, 1 tab

1994-10-17

413

Measurement of OEF and absolute CMRO2: MRI-based methods using interleaved and combined hypercapnia and hyperoxia.  

Science.gov (United States)

Blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) is most commonly used in a semi-quantitative manner to infer changes in brain activity. Despite the basis of the image contrast lying in the cerebral venous blood oxygenation level, quantification of absolute cerebral metabolic rate of oxygen consumption (CMRO2) has only recently been demonstrated. Here we examine two approaches to the calibration of fMRI signal to measure absolute CMRO2 using hypercapnic and hyperoxic respiratory challenges. The first approach is to apply hypercapnia and hyperoxia separately but interleaved in time and the second is a combined approach in which we apply hyperoxic challenges simultaneously with different levels of hypercapnia. Eleven healthy volunteers were studied at 3T using a dual gradient-echo spiral readout pulsed arterial spin labelling (ASL) imaging sequence. Respiratory challenges were conducted using an automated system of dynamic end-tidal forcing. A generalised BOLD signal model was applied, within a Bayesian estimation framework, that aims to explain the effects of modulation of CBF and arterial oxygen content to estimate venous deoxyhaemoglobin concentration ([dHb]0). Using CBF measurements combined with the estimated oxygen extraction fraction (OEF), absolute CMRO2 was calculated. The interleaved approach to hypercapnia and hyperoxia, as well as yielding estimates of CMRO2 and OEF demonstrated a significant increase in regional CBF, venous oxygen saturation (SvO2) (a decrease in OEF) and absolute CMRO2 in visual cortex in response to a continuous (20 min) visual task, demonstrating the potential for the method in measuring long term changes in CMRO2. The combined approach to oxygen and carbon dioxide modulation, as well as taking less time to acquire data, yielded whole brain grey matter estimates of CMRO2 and OEF of 184±45 ?mol/100 g/min and 0.42±0.12 respectively, along with additional estimates of the vascular parameters ?=0.33±0.06, the exponent relating relative increases in CBF to CBV, and ?=1.35±0.13, the exponent relating deoxyhaemoglobin concentration to the relaxation rate R2*. Maps of cerebrovascular and cerebral metabolic parameters were also calculated. We show that combined modulation of oxygen and carbon dioxide can offer an experimentally more efficient approach to estimating OEF and absolute CMRO2 along with the additional vascular parameters that form an important part of the commonly used calibrated fMRI signal model. PMID:23769703

Wise, Richard G; Harris, Ashley D; Stone, Alan J; Murphy, Kevin

2013-12-01

414

Intercomparisons for the agreement of radioactivity measurement laboratories in environment  

International Nuclear Information System (INIS)

Four tests having for object the evaluation of ability of laboratories that solicit a ministerial