WorldWideScience

Sample records for high-precision nd-isotopic measurements

  1. Ultra-high-precision Nd-isotope measurements of geological materials by MC-ICPMS

    DEFF Research Database (Denmark)

    Saji, Nikitha Susan; Wielandt, Daniel Kim Peel; Paton, Chad

    2016-01-01

    We report novel techniques allowing the measurement of Nd-isotope ratios with unprecedented accuracy and precision by multi-collector inductively coupled plasma mass spectrometry. Using the new protocol, we have measured the Nd-isotopic composition of rock and synthetic Nd standards as well as th...

  2. High Precision 142Nd/144Nd and 143Nd/144Nd Isotope Ratio Measurements in Rock Samples

    Science.gov (United States)

    Ali, A.; Srinivasan, G.

    2009-05-01

    The long-lived 147Sm-143Nd system with a half-life (T1/2) of 106 Gyr is generally used for geochronology. The short-lived 146Sm-142Nd system (T1/2= 103 Myr) is used as a geological tracer to track early (˜500 Ma) silicate differentiation [1] events in different planetary bodies. The isotope composition measurements by thermal ionization mass spectrometry (TIMS) require purification of Nd using chemical separation methods. This is important as an impure sample will give both a very poor ion yield and cause beam instability in the mass spectrometer, potentially resulting in a poor analysis [2]. The separation of Nd for 143Nd isotope measurement is, fairly straightforward because there is no isobaric interference of any other REE. While 142Nd isotope analysis needs chemically separated Nd fraction to be ˜100% Ce-free as latter is composed of a substantial amount of 142Ce isotope. A 4-steps technique, modified from Caro et al., [3], for the separation of Nd is established at the Cosmochemistry Laboratory of University of Toronto, Canada and applied to the measurement of Nd isotope ratios in geological reference sample BCR-2 (USGS, Columbia River basalt) using TIMS. Results of the isotopic ratios obtained for BCR-2 are in good agreement with published values [e.g., 4]. Analytical work on the samples discovered as the oldest rocks on Earth [5] from Nuvvuagittuq greenstone belt in Québec, Canada and various meteorites is in progress. An account of the procedures involved is briefly described here. All working solutions and acids were prepared using >18.2 MΩ.cm-1 H2O from a Milli-Q water system. Experiments were performed under Class 100 clean work bench with acid-cleaned apparatus and plastic-ware. The whole rock powders were weighed (20-30 mg) and dissolved in a mixture of HF and HNO3 using PFA vials and heated at 110°C. Further decomposition was done in Teflon bomb in the oven at 205°C. Later on contents of the Teflon bomb were transferred to vials and fluorides

  3. Neoarchean metamorphism recorded in high-precision Sm-Nd isotope systematics of garnets from the Jack Hills (Western Australia)

    Science.gov (United States)

    Eccles, K. A.; Baxter, E. F.; Mojzsis, S. J.; Marschall, H.; Williams, M. L.; Jercinovic, M. J.

    2013-12-01

    Studies of metasedimentary rocks from the Jack Hills, which host Earth's oldest known detrital minerals, have focused on zircon and occasionally monazite or xenotime, but no attention has been directed toward one of the most common mineral markers of metamorphism: garnet. Garnet can provide a record of the post-depositional, prograde metamorphic history of Archean metasedimentary rocks. Additionally, the use of a newly developed detrital garnet dating technique [1,2] may reveal information about pre-depositional metamorphism that could address lingering questions about the nature and timing of Earth's earliest tectonometamorphic events. Here we investigate garnet from the Jack Hills metasedimentary rocks to test whether they record in situ metamorphism or are a detrital relict of even older metamorphic events. We identified garnet in two bulk quartz-pebble conglomerate samples collected from the 'discovery' outcrop at Eranondoo Hill in the Jack Hills of Western Australia. Electron microprobe analyses of polished grains and SEM measurements of unpolished grain surfaces are consistent, revealing garnet composition indicative of a single generation/population of predominantly almandine-spessartine solid solution (~10-35% mole fraction spessartine). Compositional maps of garnet grains reveal little zoning and no discontinuities, most consistent with a single growth event. Dating Jack Hills' garnet via the Sm-Nd system is possible due to continued development of small sample analysis techniques, including running NdO+ TIMS analyses with Ta2O5 activator [3] permitting Ma for two point isochrons between clean garnet (Sm/Nd ≥ 1.0) and their leached inclusion populations [2]. Four grouped garnet grain separates from one sample yield preliminary dates of 2703.6×6.0Ma, 2612.4×6.0Ma, 2605.0×5.5Ma, and 2567.3×8.3Ma, while the second sample yielded a date of 2579.6×4.6 Ma (2σ). Compositional and geochronologic data indicate likely in situ garnet growth during a late

  4. Lifetimes in neutron-rich Nd isotopes measured by Doppler profile method

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Lister, C.J.; Morss, L.R. [and others

    1995-08-01

    Lifetimes of the rotational levels in neutron-rich even-even Nd isotopes were deduced from the analysis of the Doppler broadened line shapes. The experiment was performed at Daresbury with the Eurogam array, which at that time consisted of 45 Compton-suppressed Ge detectors and 5 Low-Energy Photon Spectrometers. The source was in the form of a 7-mm pellet which was prepared by mixing 5-mg; {sup 248}Cm and 65-mg KCl and pressing it under high pressure. Events for which three or more detectors fired were used to construct a cubic data array whose axes represented the {gamma}-ray energies and the contents of each channel the number of events with that particular combination of {gamma}-ray energies. From this cubic array, one-dimensional spectra were generated by placing gates on peaks on the other two axes. Gamma-ray spectra of even-even Nd isotopes were obtained by gating on the transitions in the complimentary Kr fragments. The gamma peaks de-exciting states with I {>=} 12 h were found to be broader than the instrumental line width due to the Doppler effect. The line shapes of they-ray peaks were fitted separately with a simple model for the feeding of the states and assuming a rotational band with constant intrinsic quadruple moment and these are shown in Fig. I-27. The quadrupole moments thus determined were found to be in good agreement with the quadrupole moments measured previously for lower spin states. Because of the success of this technique for the Nd isotopes, we intend to apply this technique to the new larger data set collected with the Eurogam II array. The results of this study were published.

  5. High precision mass measurements in Ψ and Υ families revisited

    International Nuclear Information System (INIS)

    Artamonov, A.S.; Baru, S.E.; Blinov, A.E.

    2000-01-01

    High precision mass measurements in Ψ and Υ families performed in 1980-1984 at the VEPP-4 collider with OLYA and MD-1 detectors are revisited. The corrections for the new value of the electron mass are presented. The effect of the updated radiative corrections has been calculated for the J/Ψ(1S) and Ψ(2S) mass measurements [ru

  6. High Precision Infrared Temperature Measurement System Based on Distance Compensation

    Directory of Open Access Journals (Sweden)

    Chen Jing

    2017-01-01

    Full Text Available To meet the need of real-time remote monitoring of human body surface temperature for optical rehabilitation therapy, a non-contact high-precision real-time temperature measurement method based on distance compensation was proposed, and the system design was carried out. The microcontroller controls the infrared temperature measurement module and the laser range module to collect temperature and distance data. The compensation formula of temperature with distance wass fitted according to the least square method. Testing had been performed on different individuals to verify the accuracy of the system. The results indicate that the designed non-contact infrared temperature measurement system has a residual error of less than 0.2°C and the response time isless than 0.1s in the range of 0 to 60cm. This provides a reference for developing long-distance temperature measurement equipment in optical rehabilitation therapy.

  7. High precision measurements of 26Naβ- decay

    Science.gov (United States)

    Grinyer, G. F.; Svensson, C. E.; Andreoiu, C.; Andreyev, A. N.; Austin, R. A.; Ball, G. C.; Chakrawarthy, R. S.; Finlay, P.; Garrett, P. E.; Hackman, G.; Hardy, J. C.; Hyland, B.; Iacob, V. E.; Koopmans, K. A.; Kulp, W. D.; Leslie, J. R.; MacDonald, J. A.; Morton, A. C.; Ormand, W. E.; Osborne, C. J.; Pearson, C. J.; Phillips, A. A.; Sarazin, F.; Schumaker, M. A.; Scraggs, H. C.; Schwarzenberg, J.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Wood, J. L.; Zganjar, E. F.

    2005-04-01

    High-precision measurements of the half-life and β-branching ratios for the β- decay of 26Na to 26Mg have been measured in β-counting and γ-decay experiments, respectively. A 4π proportional counter and fast tape transport system were employed for the half-life measurement, whereas the γ rays emitted by the daughter nucleus 26Mg were detected with the 8π γ-ray spectrometer, both located at TRIUMF's isotope separator and accelerator radioactive beam facility. The half-life of 26Na was determined to be T1/2=1.07128±0.00013±0.00021s, where the first error is statistical and the second systematic. The logft values derived from these experiments are compared with theoretical values from a full sd-shell model calculation.

  8. High-precision reflectivity measurements: improvements in the calibration procedure

    Science.gov (United States)

    Jupe, Marco; Grossmann, Florian; Starke, Kai; Ristau, Detlev

    2003-05-01

    The development of high quality optical components is heavily depending on precise characterization procedures. The reflectance and transmittance of laser components are the most important parameters for advanced laser applications. In the industrial fabrication of optical coatings, quality management is generally insured by spectral photometric methods according to ISO/DIS 15386 on a medium level of accuracy. Especially for high reflecting mirrors, a severe discrepancy in the determination of the absolute reflectivity can be found for spectral photometric procedures. In the first part of the CHOCLAB project, a method for measuring reflectance and transmittance with an enhanced precision was developed, which is described in ISO/WD 13697. In the second part of the CHOCLAB project, the evaluation and optimization for the presented method is scheduled. Within this framework international Round-Robin experiment is currently in progress. During this Round-Robin experiment, distinct deviations could be observed between the results of high precision measurement facilities of different partners. Based on the extended experiments, the inhomogeneity of the sample reflectivity was identified as one important origin for the deviation. Consequently, this inhomogeneity is also influencing the calibration procedure. Therefore, a method was developed that allows the calibration of the chopper blade using always the same position on the reference mirror. During the investigations, the homogeneity of several samples was characterized by a surface mapping procedure for 1064 nm. The measurement facility was extended to the additional wavelength 532 nm and a similar set-up was assembled at 10.6 μm. The high precision reflectivity procedure at the mentioned wavelengths is demonstrated for exemplary measurements.

  9. Various high precision measurements of pressure in atomic energy industry

    International Nuclear Information System (INIS)

    Aritomi, Masanori; Inoue, Akira; Hosoma, Takashi; Tanaka, Izumi; Gabane, Tsunemichi.

    1987-01-01

    As for the pressure measurement in atomic energy industry, it is mostly the measurement using differential pressure transmitters and pressure transmitters for process measurement with the general accuracy of measurement of 0.2 - 0.5 % FS/year. However, recently for the development of nuclear fusion reactors and the establishment of nuclear fuel cycle accompanying new atomic energy technology, there are the needs of the pressure measurement having higher accuracy of 0.01 % FS/year and high resolution, and quartz vibration type pressure sensors appeared. New high accuracy pressure measurement techniques were developed by the advance of data processing and the rationalization of data transmission. As the results, the measurement of the differential pressure of helium-lithium two-phase flow in the cooling system of nuclear fusion reactors, the high accuracy measuring system for the level of plutonium nitrate and other fuel substance in tanks in fuel reprocessing and conversion, the high accuracy measurement of atmospheric pressure and wind velocity in ducts, chimneys and tunnels in nuclear facilities and so on became feasible. The principle and the measured data of quartz vibration type pressure sensors are shown. (Kako, I.)

  10. Design and Implementation of High Precision Temperature Measurement Unit

    Science.gov (United States)

    Zeng, Xianzhen; Yu, Weiyu; Zhang, Zhijian; Liu, Hancheng

    2018-03-01

    Large-scale neutrino detector requires calibration of photomultiplier tubes (PMT) and electronic system in the detector, performed by plotting the calibration source with a group of designated coordinates in the acrylic sphere. Where the calibration source positioning is based on the principle of ultrasonic ranging, the transmission speed of ultrasonic in liquid scintillator of acrylic sphere is related to temperature. This paper presents a temperature measurement unit based on STM32L031 and single-line bus digital temperature sensor TSic506. The measurement data of the temperature measurement unit can help the ultrasonic ranging to be more accurate. The test results show that the temperature measurement error is within ±0.1°C, which satisfies the requirement of calibration source positioning. Take energy-saving measures, with 3.7V/50mAH lithium battery-powered, the temperature measurement unit can work continuously more than 24 hours.

  11. High-precision thickness measurements using beta backscatter

    International Nuclear Information System (INIS)

    Heckman, R.V.

    1978-11-01

    A two-axis, automated fixture for use with a high-intensity Pm-147 source and a photomultiplier-scintillation beta-backscatter probe for making thickness measurements has been designed and built. A custom interface was built to connect the system to a minicomputer, and software was written to position the tables, control the probe, and make the measurements. Measurements can be made in less time with much greater precision than by the method previously used

  12. High precision speed measurement by using interferometric techniques

    International Nuclear Information System (INIS)

    Ávila, M A Rodríguez; Valiente, R Ochoa; Trujillo, L A García

    2015-01-01

    In this work we present the experimental realization of speed measurement by the use of a two wave interferometer and digital signal processing techniques. We built an automated Michelson interferometer and using an He-Ne laser and with the use of the Fast Fourier Transform (FFT) and computer algorithms we derived a method for finding the speed of displacement. We report uncertainties in the order of 2-3 μm/s. with the use of this procedure. This brings the potential of another physical variable measurement like distance or pressure by this indirect measurement method. This approach is compared with an ultrasonic Logger Pro ® speed measurement system, and the results are compared between systems

  13. High Precision Atomic Mass Measurements: Tests of CVC and IMME

    International Nuclear Information System (INIS)

    Eronen, Tommi

    2011-01-01

    Atomic mass is one of the key ingredients in testing the Conserved Vector Current (CVC) hypothesis and Isobaric Mass Multiplet Equation (IMME). With JYFLTRAP Penning trap installation at the University of Jyvaeskylae, Finland, several atomic massses related to these studies have been measured. The performed atomic mass measurements for CVC tests cover almost all the nuclei that are relevant for these studies. To test IMME, masses in two isobaric mass chains (A = 23 and A = 32) have been determined.

  14. High Precision Atomic Mass Measurements: Tests of CVC and IMME

    Energy Technology Data Exchange (ETDEWEB)

    Eronen, Tommi [Department of Physics, University of Jyvaeskylae, FI-40014 University of Jyvaeskylae (Finland); Collaboration: JYFLTRAP Collaboration

    2011-11-30

    Atomic mass is one of the key ingredients in testing the Conserved Vector Current (CVC) hypothesis and Isobaric Mass Multiplet Equation (IMME). With JYFLTRAP Penning trap installation at the University of Jyvaeskylae, Finland, several atomic massses related to these studies have been measured. The performed atomic mass measurements for CVC tests cover almost all the nuclei that are relevant for these studies. To test IMME, masses in two isobaric mass chains (A = 23 and A = 32) have been determined.

  15. High precision measurements of the luminosity at LEP

    International Nuclear Information System (INIS)

    Pietrzyk, B.

    1994-01-01

    The art of the luminosity measurements at LEP is presented. First generation LEP detectors have measured the absolute luminosity with the precision of 0.3-0.5%. The most precise present detectors have reached the 0.07% precision and the 0.05% is not excluded in future. Center-of-mass energy dependent relative precision of the luminosity detectors and the use of the theoretical cross-section in the LEP experiments are also discussed. (author). 18 refs., 6 figs., 6 tabs

  16. High precision stress measurements in semiconductor structures by Raman microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Uhlig, Benjamin

    2009-07-01

    Stress in silicon structures plays an essential role in modern semiconductor technology. This stress has to be measured and due to the ongoing miniaturization in today's semiconductor industry, the measuring method has to meet certain requirements. The present thesis deals with the question how Raman spectroscopy can be used to measure the state of stress in semiconductor structures. In the first chapter the relation between Raman peakshift and stress in the material is explained. It is shown that detailed stress maps with a spatial resolution close to the diffraction limit can be obtained in structured semiconductor samples. Furthermore a novel procedure, the so called Stokes-AntiStokes-Difference method is introduced. With this method, topography, tool or drift effects can be distinguished from stress related influences in the sample. In the next chapter Tip-enhanced Raman Scattering (TERS) and its application for an improvement in lateral resolution is discussed. For this, a study is presented, which shows the influence of metal particles on the intensity and localization of the Raman signal. A method to attach metal particles to scannable tips is successfully applied. First TERS scans are shown and their impact on and challenges for high resolution stress measurements on semiconductor structures is explained. (orig.)

  17. Investigation of Leveling Equipment for High Precision Measurements

    International Nuclear Information System (INIS)

    Gassner, G.

    2007-01-01

    At SLAC (Stanford Linear Accelerator Center) a fully automated vertical comparator for the calibration of digital levels and invar staffs was developed by the Metrology Department in cooperation with the Institute of Engineering Geodesy and Measurement Systems at the Graz University of Technology. This vertical comparator is the first in the US. With the vertical comparator it is possible to perform system calibration and CCD camera measurements of rods. System calibration uses the height readings of the digital level at different positions of the rod and compares them with the reference readings obtained by the interferometer. In the case of CCD camera measurements, the positions of the edges in the image is determined and again compared with the interferometer readings. This document gives an overview of the current set-up of the SLAC vertical comparator and experimental results of critical applications including measurements at the end sections of the rod, at critical sighting distances, with unfocused optics and under illumination with the digital levels in use at SLAC

  18. Overview of the JYFLTRAP mass measurements and high-precision ...

    Indian Academy of Sciences (India)

    nuclei, the mass difference can be determined with much higher precision than would normally be possible since for the mass doublets the systematic uncertainties become ..... The two-neutron separation energies in N = 60 indicate the. 338 ... Masses of zinc isotopes (Z = 30) were measured up to 80Zn, providing valuable.

  19. Local high precision 3D measurement based on line laser measuring instrument

    Science.gov (United States)

    Zhang, Renwei; Liu, Wei; Lu, Yongkang; Zhang, Yang; Ma, Jianwei; Jia, Zhenyuan

    2018-03-01

    In order to realize the precision machining and assembly of the parts, the geometrical dimensions of the surface of the local assembly surfaces need to be strictly guaranteed. In this paper, a local high-precision three-dimensional measurement method based on line laser measuring instrument is proposed to achieve a high degree of accuracy of the three-dimensional reconstruction of the surface. Aiming at the problem of two-dimensional line laser measuring instrument which lacks one-dimensional high-precision information, a local three-dimensional profile measuring system based on an accurate single-axis controller is proposed. First of all, a three-dimensional data compensation method based on spatial multi-angle line laser measuring instrument is proposed to achieve the high-precision measurement of the default axis. Through the pretreatment of the 3D point cloud information, the measurement points can be restored accurately. Finally, the target spherical surface is needed to make local three-dimensional scanning measurements for accuracy verification. The experimental results show that this scheme can get the local three-dimensional information of the target quickly and accurately, and achieves the purpose of gaining the information and compensating the error for laser scanner information, and improves the local measurement accuracy.

  20. Machine vision for high-precision volume measurement applied to levitated containerless material processing

    International Nuclear Information System (INIS)

    Bradshaw, R.C.; Schmidt, D.P.; Rogers, J.R.; Kelton, K.F.; Hyers, R.W.

    2005-01-01

    By combining the best practices in optical dilatometry with numerical methods, a high-speed and high-precision technique has been developed to measure the volume of levitated, containerlessly processed samples with subpixel resolution. Containerless processing provides the ability to study highly reactive materials without the possibility of contamination affecting thermophysical properties. Levitation is a common technique used to isolate a sample as it is being processed. Noncontact optical measurement of thermophysical properties is very important as traditional measuring methods cannot be used. Modern, digitally recorded images require advanced numerical routines to recover the subpixel locations of sample edges and, in turn, produce high-precision measurements

  1. Using High-Precision Specific Gravity Measurements to Study Minerals in Undergraduate Geoscience Courses

    Science.gov (United States)

    Brandriss, Mark E.

    2010-01-01

    This article describes ways to incorporate high-precision measurements of the specific gravities of minerals into undergraduate courses in mineralogy and physical geology. Most traditional undergraduate laboratory methods of measuring specific gravity are suitable only for unusually large samples, which severely limits their usefulness for student…

  2. High Precision Measurement of the differential W and Z boson cross-sections

    CERN Document Server

    Gasnikova, Ksenia; The ATLAS collaboration

    2017-01-01

    Measurements of the Drell-Yan production of W and Z/gamma bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at center-of-mass energies of 7. The measurements are performed for W+, W- and Z/gamma bosons integrated and as a function of the boson or lepton rapidity and the Z/gamma* mass. Unprecedented precision is reached and strong constraints on Parton Distribution functions, in particular the strange density are found. Z cross sections are also measured at a center-of-mass energies of 8TeV and 13TeV, and cross-section ratios to the top-quark pair production have been derived. This ratio measurement leads to a cancellation of several systematic effects and allows therefore for a high precision comparison to the theory predictions.

  3. High-Precision Mass Measurements of Exotic Nuclei with the Triple-Trap Mass Spectrometer Isoltrap

    CERN Multimedia

    Blaum, K; Zuber, K T; Stanja, J

    2002-01-01

    The masses of close to 200 short-lived nuclides have already been measured with the mass spectrometer ISOLTRAP with a relative precision between 1$\\times$10$^{-7}$ and 1$\\times$10^{-8}$. The installatin of a radio-frequency quadrupole trap increased the overall efficiency by two orders of magnitude which is at present about 1%. In a recent upgrade, we installed a carbon cluster laser ion source, which will allow us to use carbon clusters as mass references for absolute mass measurements. Due to these improvements and the high reliability of ISOLTRAP we are now able to perform accurate high-precision mass measurements all over the nuclear chart. We propose therefore mass measurements on light, medium and heavy nuclides on both sides of the valley of stability in the coming four years. ISOLTRAP is presently the only instrument capable of the high precision required for many of the proposed studies.

  4. MRPC-PET: A new technique for high precision time and position measurements

    International Nuclear Information System (INIS)

    Doroud, K.; Hatzifotiadou, D.; Li, S.; Williams, M.C.S.; Zichichi, A.; Zuyeuski, R.

    2011-01-01

    The purpose of this paper is to consider a new technology for medical diagnosis: the MRPC-PET. This technology allows excellent time resolution together with 2-D position information thus providing a fundamental step in this field. The principle of this method is based on the Multigap Resistive Plate Chamber (MRPC) capable of high precision time measurements. We have previously found that the route to precise timing is differential readout (this requires matching anode and cathode strips); thus crossed strip readout schemes traditionally used for 2-D readout cannot be exploited. In this paper we consider the time difference from the two ends of the strip to provide a high precision measurement along the strip; the average time gives precise timing. The MRPC-PET thus provides a basic step in the field of medical technology: excellent time resolution together with 2-D position measurement.

  5. Recent developments for high-precision mass measurements of the heaviest elements at SHIPTRAP

    International Nuclear Information System (INIS)

    Minaya Ramirez, E.; Ackermann, D.; Blaum, K.; Block, M.; Droese, C.; Düllmann, Ch. E.; Eibach, M.; Eliseev, S.; Haettner, E.; Herfurth, F.; Heßberger, F.P.

    2013-01-01

    Highlights: • Direct high-precision mass measurements of No and Lr isotopes performed. • High-precision mass measurements with a count rate of 1 ion/hour demonstrated. • The results provide anchor points for a large region connected by alpha-decay chains. • The binding energies determine the strength of the deformed shell closure N = 152. • Technical developments and new techniques will pave the way towards heavier elements. -- Abstract: Atomic nuclei far from stability continue to challenge our understanding. For example, theoretical models have predicted an “island of stability” in the region of the superheavy elements due to the closure of spherical proton and neutron shells. Depending on the model, these are expected at Z = 114, 120 or even 126 and N = 172 or 184. Valuable information on the road to the island of stability is derived from high-precision mass measurements, which give direct access to binding energies of short-lived trans-uranium nuclei. Recently, direct mass measurements at SHIPTRAP have been extended to nobelium and lawrencium isotopes around the deformed shell gap N = 152. In order to further extend mass measurements to the region of superheavy elements, new technical developments are required to increase the performance of our setup. The sensitivity will increase through the implementation of a new detection method, where observation of one single ion is sufficient. Together with the use of a more efficient gas stopping cell, this will us allow to significantly enhance the overall efficiency of SHIPTRAP

  6. Nd isotopes and crustal growth rate

    International Nuclear Information System (INIS)

    Albarede, F.

    1988-01-01

    Sm/Nd isotopic constraints on crustal growth is discussed. In order to constrain Sm/Nd fractionation between continental crust and depleted mantle, an extensive data base of isotopic measurements (assumed to be adequately representative of continental crust) was compiled. The results imply that the evolution of depleted mantles was roughly linear, with no major discontinuities over the course of geologic time. This is different from other determinations of depleting mantle evolution, which show nonlinear behavior. The Sm/Nd evolution lines for continental crust and depleted mantle intersect between 3.8 to 4.0 Ga, which may indicate that the onset of continental growth was later than 4.5 Ga. A mathematical model is described, the results of which imply that time integrated crustal additions from the mantle are about 1.8 to 2.5 cu km/a, whereas crustal subtractions by sediment recycling are about 0.6 to 1.5 cu km/a. This results in a net time integrated crustal growth rate of about 1 cu km/a, which is similar to present day rates determined, for example, by Reymer and Schubert

  7. High-Precision Half-Life Measurement for the Superallowed β+ Emitter Alm26

    Science.gov (United States)

    Finlay, P.; Ettenauer, S.; Ball, G. C.; Leslie, J. R.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Bandyopadhyay, D.; Cross, D. S.; Demand, G.; Djongolov, M.; Garrett, P. E.; Green, K. L.; Grinyer, G. F.; Hackman, G.; Leach, K. G.; Pearson, C. J.; Phillips, A. A.; Sumithrarachchi, C. S.; Triambak, S.; Williams, S. J.

    2011-01-01

    A high-precision half-life measurement for the superallowed β+ emitter Alm26 was performed at the TRIUMF-ISAC radioactive ion beam facility yielding T1/2=6346.54±0.46stat±0.60systms, consistent with, but 2.5 times more precise than, the previous world average. The Alm26 half-life and ft value, 3037.53(61) s, are now the most precisely determined for any superallowed β decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected Ft value for Alm26, 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi β-decay studies used to test the conserved vector current hypothesis and determine the Vud element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

  8. Method of high precision interval measurement in pulse laser ranging system

    Science.gov (United States)

    Wang, Zhen; Lv, Xin-yuan; Mao, Jin-jin; Liu, Wei; Yang, Dong

    2013-09-01

    Laser ranging is suitable for laser system, for it has the advantage of high measuring precision, fast measuring speed,no cooperative targets and strong resistance to electromagnetic interference,the measuremen of laser ranging is the key paremeters affecting the performance of the whole system.The precision of the pulsed laser ranging system was decided by the precision of the time interval measurement, the principle structure of laser ranging system was introduced, and a method of high precision time interval measurement in pulse laser ranging system was established in this paper.Based on the analysis of the factors which affected the precision of range measure,the pulse rising edges discriminator was adopted to produce timing mark for the start-stop time discrimination,and the TDC-GP2 high precision interval measurement system based on TMS320F2812 DSP was designed to improve the measurement precision.Experimental results indicate that the time interval measurement method in this paper can obtain higher range accuracy. Compared with the traditional time interval measurement system,the method simplifies the system design and reduce the influence of bad weather conditions,furthermore,it satisfies the requirements of low costs and miniaturization.

  9. Tests of a Fast Plastic Scintillator for High-Precision Half-Life Measurements

    Science.gov (United States)

    Laffoley, A. T.; Dunlop, R.; Finlay, P.; Leach, K. G.; Michetti-Wilson, J.; Rand, E. T.; Svensson, C. E.; Grinyer, G. F.; Thomas, J. C.; Ball, G.; Garnsworthy, A. B.; Hackman, G.; Orce, J. N.; Triambak, S.; Williams, S. J.; Andreoiu, C.; Cross, D.

    2013-03-01

    A fast plastic scintillator detector is evaluated for possible use in an ongoing program of high-precision half-life measurements of short lived β emitters. Using data taken at TRI-UMF's Isotope Separator and Accelerator Facility with a radioactive 26Na beam, a detailed investigation of potential systematic effects with this new detector setup is being performed. The technique will then be applied to other β-decay half-life measurements including the superallowed Fermi β emitters 10C, 14O, and T = 1/2 decay of 15O.

  10. Precision mechatronics based on high-precision measuring and positioning systems and machines

    Science.gov (United States)

    Jäger, Gerd; Manske, Eberhard; Hausotte, Tino; Mastylo, Rostyslav; Dorozhovets, Natalja; Hofmann, Norbert

    2007-06-01

    Precision mechatronics is defined in the paper as the science and engineering of a new generation of high precision systems and machines. Nanomeasuring and nanopositioning engineering represents important fields of precision mechatronics. The nanometrology is described as the today's limit of the precision engineering. The problem, how to design nanopositioning machines with uncertainties as small as possible will be discussed. The integration of several optical and tactile nanoprobes makes the 3D-nanopositioning machine suitable for various tasks, such as long range scanning probe microscopy, mask and wafer inspection, nanotribology, nanoindentation, free form surface measurement as well as measurement of microoptics, precision molds, microgears, ring gauges and small holes.

  11. Investigation of the proton-neutron interaction by high-precision nuclear mass measurements

    CERN Multimedia

    Savreux, R P; Akkus, B

    2007-01-01

    We propose to measure the atomic masses of a series of short-lived nuclides, including $^{70}$Ni, $^{122-130}$Cd, $^{134}$Sn, $^{138,140}$Xe, $^{207-210}$Hg, and $^{223-225}$Rn, that contribute to the investigation of the proton-neutron interaction and its role in nuclear structure. The high-precision mass measurements are planned for the Penning trap mass spectrometer ISOLTRAP that reaches the required precision of 10 keV in the nuclear mass determination.

  12. High precision instrumentation for measuring the true exposure time in diagnostic X-ray examinations

    International Nuclear Information System (INIS)

    Silva, Danubia B.; Santos, Marcus A.P.; Barros, Fabio R.; Santos, Luiz A.P.

    2013-01-01

    One of the most important physical quantities to be evaluated in diagnostic radiology is the radiation exposure time experimented by the patient during the X-ray examination. IAEA and WHO organizations have suggested that any country must create a quality surveillance program to verify if each type of ionizing radiation equipment used in the hospitals and medical clinics are in conformity with the accepted uncertainties following the international standards. The purpose of this work is to present a new high precision methodology for measuring true exposure time in diagnostic X-ray examinations: pulsed, continuous or digital one. An electronic system named CronoX, which will be soon registered at the Brazilian Patent Office (INPI), is the equipment that provides such a high precision measurement. The principle of measurement is based on the electrical signal captured by a sensor that enters in a regeneration amplifier to transform it in a digital signal, which is treated by a microprocessor (uP). The signal treatment results in a two measured times: 1) T rx , the true X-ray exposure time; 2) T nx , the time in which the X-ray machine is repeatedly cut off during the pulsed irradiation and there is no delivery dose to the patient. Conventional Polymat X-ray equipment and dental X-ray machines were used to generate X-ray photons and take the measurements with the electronic systems. The results show that such a high precision instrumentation displays the true exposure time in diagnostic X-ray examinations and indicates a new method to be purposed for the quality surveillance programs in radiology. (author)

  13. High Precision Measurement of the differential vector boson cross-sections with the ATLAS detector

    CERN Document Server

    Armbruster, Aaron James; The ATLAS collaboration

    2017-01-01

    Measurements of the Drell-Yan production of W and Z/gamma bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at center-of-mass energies of 7. The measurements are performed for W+, W- and Z/gamma bosons integrated and as a function of the boson or lepton rapidity and the Z/gamma* mass. Unprecedented precision is reached and strong constraints on Parton Distribution functions, in particular the strange density are found. Z cross sections are also measured at center-of-mass energies of 8 eV and 13TeV, and cross-section ratios to the top-quark pair production have been derived. This ratio measurement leads to a cancellation of systematic effects and allows for a high precision comparison to the theory predictions. The cross section of single W events has also been measured precisely at center-of-mass energies of 8TeV and 13TeV and the W charge asymmetry has been determ...

  14. Optimization of the data taking strategy for a high precision τ mass measurement

    International Nuclear Information System (INIS)

    Wang, Y.K.; Mo, X.H.; Yuan, C.Z.; Liu, J.P.

    2007-01-01

    To achieve a high precision τ mass (m τ ) measurement at the forthcoming high luminosity experiment, Monte Carlo simulation and sampling technique are adopted to simulate various data taking cases from which the optimal scheme is determined. The study indicates that when m τ is the sole parameter to be fit, the optimal energy for data taking is located near the τ + τ - production threshold in the vicinity of the largest derivative of the cross-section to energy; one point in the optimal position with luminosity around 63pb -1 is sufficient for getting a statistical precision of 0.1MeV/c 2 or better

  15. High-precision branching-ratio measurement for the superallowed β+ emitter 26Alm

    Science.gov (United States)

    Finlay, P.; Ball, G. C.; Leslie, J. R.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Bandyopadhyay, D.; Cross, D. S.; Demand, G.; Djongolov, M.; Ettenauer, S.; Garrett, P. E.; Green, K. L.; Grinyer, G. F.; Hackman, G.; Leach, K. G.; Pearson, C. J.; Phillips, A. A.; Rand, E. T.; Sumithrarachchi, C. S.; Triambak, S.; Williams, S. J.

    2012-05-01

    A high-precision branching-ratio measurement for the superallowed β+ emitter 26Alm was performed at the TRIUMF-ISAC radioactive ion beam facility. An upper limit of ⩽12 ppm at 90% confidence level was found for the second forbidden β+ decay of 26Alm to the 21+ state at 1809 keV in 26Mg. An inclusive upper limit of ⩽15 ppm at 90% confidence level was found when considering all possible nonanalog β+/EC decay branches of 26Alm, resulting in a superallowed branching ratio of 100.0000-0.0015+0%.

  16. Frequency Comb Driven Raman Transitions in the THz Range: High Precision Isotope Shift Measurements in Ca+

    DEFF Research Database (Denmark)

    Meyer, Steffen

    2017-01-01

    and frequency resolved optical gating (FROG) are used, and the two frequency comb systems used for the experiments are thoroughly characterized, a Coherent Mira Ti:sapph oscillator and a MenloSystems fiber based frequency comb system. The potential of frequency comb driven Raman transitions is shown...... transition frequencies typically are on the order of a few THz. High precision measurements on these ions have many intriguing applications, for example the test of time-variations of fundamental constants, ultracold chemistry on the quantum level, and quantum information and computing, to name just a few...

  17. High-precision mass measurements for the rp-process at JYFLTRAP

    Directory of Open Access Journals (Sweden)

    Canete Laetitia

    2017-01-01

    Full Text Available The double Penning trap JYFLTRAP at the University of Jyväskylä has been successfully used to achieve high-precision mass measurements of nuclei involved in the rapid proton-capture (rp process. A precise mass measurement of 31Cl is essential to estimate the waiting point condition of 30S in the rp-process occurring in type I x-ray bursts (XRBs. The mass-excess of 31C1 measured at JYFLTRAP, -7034.7(3.4 keV, is 15 more precise than the value given in the Atomic Mass Evaluation 2012. The proton separation energy Sp determined from the new mass-excess value confirmed that 30S is a waiting point, with a lower-temperature limit of 0.44 GK. The mass of 52Co effects both 51Fe(p,γ52Co and 52Co(p,γ53Ni reactions. The mass-excess value measured, - 34 331.6(6.6 keV is 30 times more precise than the value given in AME2012. The Q values for the 51Fe(p,γ52Co and 52Co(p,γ53Ni reactions are now known with a high precision, 1418(11 keV and 2588(26 keV respectively. The results show that 52Co is more proton bound and 53Ni less proton bound than what was expected from the extrapolated value.

  18. Proceedings, High-Precision $\\alpha_s$ Measurements from LHC to FCC-ee

    Energy Technology Data Exchange (ETDEWEB)

    d' Enterria, David [CERN; Skands, Peter Z. [Monash U.

    2015-01-01

    This document provides a writeup of all contributions to the workshop on "High precision measurements of $\\alpha_s$: From LHC to FCC-ee" held at CERN, Oct. 12--13, 2015. The workshop explored in depth the latest developments on the determination of the QCD coupling $\\alpha_s$ from 15 methods where high precision measurements are (or will be) available. Those include low-energy observables: (i) lattice QCD, (ii) pion decay factor, (iii) quarkonia and (iv) $\\tau$ decays, (v) soft parton-to-hadron fragmentation functions, as well as high-energy observables: (vi) global fits of parton distribution functions, (vii) hard parton-to-hadron fragmentation functions, (viii) jets in $e^\\pm$p DIS and $\\gamma$-p photoproduction, (ix) photon structure function in $\\gamma$-$\\gamma$, (x) event shapes and (xi) jet cross sections in $e^+e^-$ collisions, (xii) W boson and (xiii) Z boson decays, and (xiv) jets and (xv) top-quark cross sections in proton-(anti)proton collisions. The current status of the theoretical and experimental uncertainties associated to each extraction method, the improvements expected from LHC data in the coming years, and future perspectives achievable in $e^+e^-$ collisions at the Future Circular Collider (FCC-ee) with $\\cal{O}$(1--100 ab$^{-1}$) integrated luminosities yielding 10$^{12}$ Z bosons and jets, and 10$^{8}$ W bosons and $\\tau$ leptons, are thoroughly reviewed. The current uncertainty of the (preliminary) 2015 strong coupling world-average value, $\\alpha_s(m_Z)$ = 0.1177 $\\pm$ 0.0013, is about 1\\%. Some participants believed this may be reduced by a factor of three in the near future by including novel high-precision observables, although this opinion was not universally shared. At the FCC-ee facility, a factor of ten reduction in the $\\alpha_s$ uncertainty should be possible, mostly thanks to the huge Z and W data samples available.

  19. Computer-controlled detection system for high-precision isotope ratio measurements

    International Nuclear Information System (INIS)

    McCord, B.R.; Taylor, J.W.

    1986-01-01

    In this paper the authors describe a detection system for high-precision isotope ratio measurements. In this new system, the requirement for a ratioing digital voltmeter has been eliminated, and a standard digital voltmeter interfaced to a computer is employed. Instead of measuring the ratio of the two steadily increasing output voltages simultaneously, the digital voltmeter alternately samples the outputs at a precise rate over a certain period of time. The data are sent to the computer which calculates the rate of charge of each amplifier and divides the two rates to obtain the isotopic ratio. These results simulate a coincident measurement of the output of both integrators. The charge rate is calculated by using a linear regression method, and the standard error of the slope gives a measure of the stability of the system at the time the measurement was taken

  20. High-precision branching ratio measurement for the superallowed β+ emitter Ga62

    Science.gov (United States)

    Finlay, P.; Ball, G. C.; Leslie, J. R.; Svensson, C. E.; Towner, I. S.; Austin, R. A. E.; Bandyopadhyay, D.; Chaffey, A.; Chakrawarthy, R. S.; Garrett, P. E.; Grinyer, G. F.; Hackman, G.; Hyland, B.; Kanungo, R.; Leach, K. G.; Mattoon, C. M.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Ressler, J. J.; Sarazin, F.; Savajols, H.; Schumaker, M. A.; Wong, J.

    2008-08-01

    A high-precision branching ratio measurement for the superallowed β+ decay of Ga62 was performed at the Isotope Separator and Accelerator (ISAC) radioactive ion beam facility. The 8π spectrometer, an array of 20 high-purity germanium detectors, was employed to detect the γ rays emitted following Gamow-Teller and nonanalog Fermi β+ decays of Ga62, and the SCEPTAR plastic scintillator array was used to detect the emitted β particles. Thirty γ rays were identified following Ga62 decay, establishing the superallowed branching ratio to be 99.858(8)%. Combined with the world-average half-life and a recent high-precision Q-value measurement for Ga62, this branching ratio yields an ft value of 3074.3±1.1 s, making Ga62 among the most precisely determined superallowed ft values. Comparison between the superallowed ft value determined in this work and the world-average corrected F tmacr value allows the large nuclear-structure-dependent correction for Ga62 decay to be experimentally determined from the CVC hypothesis to better than 7% of its own value, the most precise experimental determination for any superallowed emitter. These results provide a benchmark for the refinement of the theoretical description of isospin-symmetry breaking in A⩾62 superallowed decays.

  1. High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q2

    Energy Technology Data Exchange (ETDEWEB)

    Xiaohui Zhan

    2009-12-01

    A high precision measurement of the proton elastic form factor ratio µpGEp/GMp in the range Q2 = 0.3–0.7 GeV2/c2 was performed using recoil polarimetry in Jefferson Lab Hall A. In this low Q2 range, previous data from LEDEX [5] along with many fits and calculations [2, 3, 4] indicate substantial deviations of the ratio from unity. In this new measurement, with 80% polarized electron beam for 24 days, we are able to achieve <1% statistical uncertainty. Preliminary results are a few percent lower than expected from previous world data and fits, indicating a smaller GEp at this region. Beyond the intrinsic interest in nucleon structure, the improved form factor measurements also have implications for DVCS, determinations of the proton Zemach radius and strangeness form factors through parity violation experiments.

  2. High-precision relative position and attitude measurement for on-orbit maintenance of spacecraft

    Science.gov (United States)

    Zhu, Bing; Chen, Feng; Li, Dongdong; Wang, Ying

    2018-02-01

    In order to realize long-term on-orbit running of satellites, space stations, etc spacecrafts, in addition to the long life design of devices, The life of the spacecraft can also be extended by the on-orbit servicing and maintenance. Therefore, it is necessary to keep precise and detailed maintenance of key components. In this paper, a high-precision relative position and attitude measurement method used in the maintenance of key components is given. This method mainly considers the design of the passive cooperative marker, light-emitting device and high resolution camera in the presence of spatial stray light and noise. By using a series of algorithms, such as background elimination, feature extraction, position and attitude calculation, and so on, the high precision relative pose parameters as the input to the control system between key operation parts and maintenance equipment are obtained. The simulation results show that the algorithm is accurate and effective, satisfying the requirements of the precision operation technique.

  3. Compendium of Neutron Beam Facilities for High Precision Nuclear Data Measurements

    International Nuclear Information System (INIS)

    2014-07-01

    The recent advances in the development of nuclear science and technology, demonstrating the globally growing economy, require highly accurate, powerful simulations and precise analysis of the experimental results. Confidence in these results is still determined by the accuracy of the atomic and nuclear input data. For studying material response, neutron beams produced from accelerators and research reactors in broad energy spectra are reliable and indispensable tools to obtain high accuracy experimental results for neutron induced reactions. The IAEA supports the accomplishment of high precision nuclear data using nuclear facilities in particular, based on particle accelerators and research reactors around the world. Such data are essential for numerous applications in various industries and research institutions, including the safety and economical operation of nuclear power plants, future fusion reactors, nuclear medicine and non-destructive testing technologies. The IAEA organized and coordinated the technical meeting Use of Neutron Beams for High Precision Nuclear Data Measurements, in Budapest, Hungary, 10–14 December 2012. The meeting was attended by participants from 25 Member States and three international organizations — the European Organization for Nuclear Research (CERN), the Joint Research Centre (JRC) and the Organisation for Economic Co-operation and Development (OECD) Nuclear Energy Agency (OECD/NEA). The objectives of the meeting were to provide a forum to exchange existing know-how and to share the practical experiences of neutron beam facilities and associated instrumentation, with regard to the measurement of high precision nuclear data using both accelerators and research reactors. Furthermore, the present status and future developments of worldwide accelerator and research reactor based neutron beam facilities were discussed. This publication is a summary of the technical meeting and additional materials supplied by the international

  4. Compendium of Neutron Beam Facilities for High Precision Nuclear Data Measurements. Annex: Individual Reports

    International Nuclear Information System (INIS)

    2014-07-01

    The recent advances in the development of nuclear science and technology, demonstrating the globally growing economy, require highly accurate, powerful simulations and precise analysis of the experimental results. Confidence in these results is still determined by the accuracy of the atomic and nuclear input data. For studying material response, neutron beams produced from accelerators and research reactors in broad energy spectra are reliable and indispensable tools to obtain high accuracy experimental results for neutron induced reactions. The IAEA supports the accomplishment of high precision nuclear data using nuclear facilities in particular, based on particle accelerators and research reactors around the world. Such data are essential for numerous applications in various industries and research institutions, including the safety and economical operation of nuclear power plants, future fusion reactors, nuclear medicine and non-destructive testing technologies. The IAEA organized and coordinated the technical meeting Use of Neutron Beams for High Precision Nuclear Data Measurements, in Budapest, Hungary, 10–14 December 2012. The meeting was attended by participants from 25 Member States and three international organizations — the European Organization for Nuclear Research (CERN), the Joint Research Centre (JRC) and the Organisation for Economic Co-operation and Development (OECD) Nuclear Energy Agency (OECD/NEA). The objectives of the meeting were to provide a forum to exchange existing know-how and to share the practical experiences of neutron beam facilities and associated instrumentation, with regard to the measurement of high precision nuclear data using both accelerators and research reactors. Furthermore, the present status and future developments of worldwide accelerator and research reactor based neutron beam facilities were discussed. This publication is a summary of the technical meeting and additional materials supplied by the international

  5. Upgrade of the SPIRAL identification station for high-precision measurements of nuclear β decay

    Science.gov (United States)

    Grinyer, G. F.; Thomas, J. C.; Blank, B.; Bouzomita, H.; Austin, R. A. E.; Ball, G. C.; Bucaille, F.; Delahaye, P.; Finlay, P.; Frémont, G.; Gibelin, J.; Giovinazzo, J.; Grinyer, J.; Kurtukian-Nieto, T.; Laffoley, A. T.; Leach, K. G.; Lefèvre, A.; Legruel, F.; Lescalié, G.; Perez-Loureiro, D.

    2014-03-01

    The low-energy identification station at SPIRAL (Système de Production d'Ions Radioactifs Accélérés en Ligne) has been upgraded for studying the β decays of short-lived radioactive isotopes and to perform high-precision half-life and branching-ratio measurements for superallowed Fermi and isospin T=1/2 mirror β decays. These new capabilities, combined with an existing Paul trap setup for measurements of β-ν angular-correlation coefficients, provide a powerful facility for investigating fundamental properties of the electroweak interaction through nuclear β decays. A detailed description of the design study, construction, and first results obtained from an in-beam commissioning experiment on the β+ decays 14 O and 17F are presented.

  6. a High-Precision Branching-Ratio Measurement for the Superallowed β+ Emitter 74Rb

    Science.gov (United States)

    Dunlop, R.; Chagnon-Lessard, S.; Finlay, P.; Garrett, P. E.; Hadinia, B.; Leach, K. G.; Svensson, C. E.; Wong, J.; Ball, G.; Garnsworthy, A. B.; Glister, J.; Hackman, G.; Tardiff, E. R.; Triambak, S.; Williams, S. J.; Leslie, J. R.; Andreoiu, C.; Chester, A.; Cross, D.; Starosta, K.; Yates, S. W.; Zganjar, E. F.

    2013-03-01

    Precision measurements of superallowed Fermi beta decay allow for tests of the Cabibbo-Kobayashi-Maskawa matrix (CKM) unitarity, the conserved vector current hypothesis, and the magnitude of isospin-symmetry-breaking effects in nuclei. A high-precision measurement of the branching ratio for the β+ decay of 74Rb has been performed at the Isotope Separator and ACcelerator (ISAC) facility at TRIUMF. The 8π spectrometer, an array of 20 close-packed HPGe detectors, was used to detect gamma rays emitted following the decay of 74Rb. PACES, an array of 5 Si(Li) detectors, was used to detect emitted conversion electrons, while SCEPTAR, an array of plastic scintillators, was used to detect emitted beta particles. A total of 51γ rays have been identified following the decay of 21 excited states in the daughter nucleus 74Kr.

  7. High precision measurements of carbon isotopic ratio of atmospheric methane using a continuous flow mass spectrometer

    Directory of Open Access Journals (Sweden)

    Shinji Morimoto

    2009-03-01

    Full Text Available A high-precision measurement system for the carbon isotope ratio of atmospheric CH4 (δ^(13CH_4 was developed using a pre-concentration device for CH4 and a gas chromatograph-combustion-isotope ratio mass spectrometer (GC-C-IRMS. The measurement system required 100 mlSTP of an atmospheric air sample, corresponding to approximately 0.18μlSTP of CH_4, to determine the δ^(13CH_4 value with a reproducibility of 0.07‰. Replicated analyses of a CH_4-in-air standard gas during the period from 2002 to 2008 indicated that the value of δ^(13CH_4 measured by this system was consistent within the measurement reproducibility. To evaluate the δ^(13CH_4 measurement system, thus developed, diurnal variations of the atmospheric CH_4 concentration and δ^(13CH_4 were observed in the northern part of the Tokyo metropolitan area. From the relationship between the CH_4 concentration and δ^(13CH_4, dominant sources of the observed CH4 fluctuations were identified.

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

    Directory of Open Access Journals (Sweden)

    Ciro Del Negro

    2011-12-01

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

  9. High-precision branching-ratio measurement for the superallowed β+ emitter 74Rb

    Science.gov (United States)

    Dunlop, R.; Ball, G. C.; Leslie, J. R.; Svensson, C. E.; Towner, I. S.; Andreoiu, C.; Chagnon-Lessard, S.; Chester, A.; Cross, D. S.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Glister, J.; Hackman, G.; Hadinia, B.; Leach, K. G.; Rand, E. T.; Starosta, K.; Tardiff, E. R.; Triambak, S.; Williams, S. J.; Wong, J.; Yates, S. W.; Zganjar, E. F.

    2013-10-01

    A high-precision branching-ratio measurement for the superallowed β+ decay of 74Rb was performed at the TRIUMF Isotope Separator and Accelerator (ISAC) radioactive ion-beam facility. The scintillating electron-positron tagging array (SCEPTAR), composed of 10 thin plastic scintillators, was used to detect the emitted β particles; the 8π spectrometer, an array of 20 Compton-suppressed HPGe detectors, was used for detecting γ rays that were emitted following Gamow-Teller and nonanalog Fermi β+ decays of 74Rb; and the Pentagonal Array of Conversion Electron Spectrometers (PACES), an array of 5 Si(Li) detectors, was employed for measuring β-delayed conversion electrons. Twenty-three excited states were identified in 74Kr following 8.241(4)×108 detected 74Rb β decays. A total of 58 γ-ray and electron transitions were placed in the decay scheme, allowing the superallowed branching ratio to be determined as B0=99.545(31)%. Combined with previous half-life and Q-value measurements, the superallowed branching ratio measured in this work leads to a superallowed ft value of 3082.8(65) s. Comparisons between this superallowed ft value and the world-average-corrected Ft¯ value, as well as the nonanalog Fermi branching ratios determined in this work, provide guidance for theoretical models of the isospin-symmetry-breaking corrections in this mass region.

  10. High-precision branching ratio measurement for the superallowed β+ emitter 62Ga

    International Nuclear Information System (INIS)

    Finlay, P.E.J.

    2007-01-01

    A high-precision branching ratio measurement for the superallowed β + decay of 62 Ga was performed at the Isotope Separator and Accelerator radioactive ion beam facility. An array of 20 high-purity germanium detectors known as the 8π spectrometer was employed to detect the rays emitted following the Gamow-Teller and non-analog Fermi decays of 62 Ga, while the plastic scintillator array known as SCEPTAR was used to detect the emitted particles. A total of 32 γ rays were identified, establishing the superallowed branching ratio to be 99:859(8)%. Combined with the most recent half-life and Q-value measurements for 62 Ga, this branching ratio yields an ft-value of 3074.3 ± 1.1 s. Comparisons between the superallowed ft-value determined in this work and the world average Ft-bar are made, providing a benchmark for the refinement of theoretical models used to describe isospin-symmetry breaking in A ≥ 62 nuclei. (author)

  11. A novel approach for pulse width measurements with a high precision (8 ps RMS) TDC in an FPGA

    International Nuclear Information System (INIS)

    Ugur, C.; Linev, S.; Schweitzer, T.; Traxler, M.; Michel, J.

    2016-01-01

    High precision time measurements are a crucial element in particle identification experiments, which likewise require pulse width information for Time-over-Threshold (ToT) measurements and charge measurements (correlated with pulse width). In almost all of the FPGA-based TDC applications, pulse width measurements are implemented using two of the TDC channels for leading and trailing edge time measurements individually. This method however, requires twice the number of resources. In this paper we present the latest precision improvements in the high precision TDC (8 ps RMS) developed before [1], as well as the novel way of measuring ToT using a single TDC channel, while still achieving high precision (as low as 11.7 ps RMS). The effect of voltage, generated by a DC-DC converter, over the precision is also discussed. Finally, the outcome of the temperature change over the pulse width measurement is shown and a correction method is suggested to limit the degradation

  12. High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

    Science.gov (United States)

    Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

    2016-01-01

    We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

  13. A high precision method for quantitative measurements of reactive oxygen species in frozen biopsies.

    Directory of Open Access Journals (Sweden)

    Kirsti Berg

    Full Text Available OBJECTIVE: An electron paramagnetic resonance (EPR technique using the spin probe cyclic hydroxylamine 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine (CMH was introduced as a versatile method for high precision quantification of reactive oxygen species, including the superoxide radical in frozen biological samples such as cell suspensions, blood or biopsies. MATERIALS AND METHODS: Loss of measurement precision and accuracy due to variations in sample size and shape were minimized by assembling the sample in a well-defined volume. Measurement was carried out at low temperature (150 K using a nitrogen flow Dewar. The signal intensity was measured from the EPR 1st derivative amplitude, and related to a sample, 3-carboxy-proxyl (CP• with known spin concentration. RESULTS: The absolute spin concentration could be quantified with a precision and accuracy better than ±10 µM (k = 1. The spin concentration of samples stored at -80°C could be reproduced after 6 months of storage well within the same error estimate. CONCLUSION: The absolute spin concentration in wet biological samples such as biopsies, water solutions and cell cultures could be quantified with higher precision and accuracy than normally achievable using common techniques such as flat cells, tissue cells and various capillary tubes. In addition; biological samples could be collected and stored for future incubation with spin probe, and also further stored up to at least six months before EPR analysis, without loss of signal intensity. This opens for the possibility to store and transport incubated biological samples with known accuracy of the spin concentration over time.

  14. Technical accuracy of a neuronavigation system measured with a high-precision mechanical micromanipulator.

    Science.gov (United States)

    Kaus, M; Steinmeier, R; Sporer, T; Ganslandt, O; Fahlbusch, R

    1997-12-01

    This study was designed to determine and evaluate the different system-inherent sources of erroneous target localization of a light-emitting diode (LED)-based neuronavigation system (StealthStation, Stealth Technologies, Boulder, CO). The localization accuracy was estimated by applying a high-precision mechanical micromanipulator to move and exactly locate (+/- 0.1 micron) the pointer at multiple positions in the physical three-dimensional space. The localization error was evaluated by calculating the spatial distance between the (known) LED positions and the LED coordinates measured by the neuronavigator. The results are based on a study of approximately 280,000 independent coordinate measurements. The maximum localization error detected was 0.55 +/- 0.29 mm, with the z direction (distance to the camera array) being the most erroneous coordinate. Minimum localization error was found at a distance of 1400 mm from the central camera (optimal measurement position). Additional error due to 1) mechanical vibrations of the camera tripod (+/- 0.15 mm) and the reference frame (+/- 0.08 mm) and 2) extrapolation of the pointer tip position from the LED coordinates of at least +/- 0.12 mm were detected, leading to a total technical error of 0.55 +/- 0.64 mm. Based on this technical accuracy analysis, a set of handling recommendations is proposed, leading to an improved localization accuracy. The localization error could be reduced by 0.3 +/- 0.15 mm by correct camera positioning (1400 mm distance) plus 0.15 mm by vibration-eliminating fixation of the camera. Correct handling of the probe during the operation may improve the accuracy by up to 0.1 mm.

  15. High-Precision Half-Life Measurements for the Superallowed Fermi β+ Emitters 14O and 18Ne

    Science.gov (United States)

    Laffoley, A. T.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Bender, P. C.; Bidaman, H.; Bildstein, V.; Blank, B.; Bouzomita, H.; Cross, D. S.; Deng, G.; Diaz Varela, A.; Dunlop, M. R.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P.; Giovinazzo, J.; Grinyer, G. F.; Grinyer, J.; Hadinia, B.; Jamieson, D. S.; Jigmeddorj, B.; Ketelhut, S.; Kisliuk, D.; Leach, K. G.; Leslie, J. R.; MacLean, A.; Miller, D.; Mills, B.; Moukaddam, M.; Radich, A. J.; Rajabali, M. M.; Rand, E. T.; Svensson, C. E.; Tardiff, E.; Thomas, J. C.; Turko, J.; Voss, P.; Unsworth, C.

    High-precision half-life measurements, at the level of ±0.04%, for the superallowed Fermi emitters 14O and 18Ne have been performed at TRIUMF's Isotope Separator and Accelerator facility. Using 3 independent detector systems, a gas-proportional counter, a fast plastic scintillator, and a high-purity germanium array, a series of direct β and γ counting measurements were performed for each of the isotopes. In the case of 14O, these measurements were made to help resolve an existing discrepancy between detection methods, whereas for 18Ne the half-life precision has been improved in anticipation of forthcoming high-precision branching ratio measurements.

  16. High-precision measurement of strong-interaction effects in pionic deuterium

    Energy Technology Data Exchange (ETDEWEB)

    Strauch, Thomas

    2009-06-30

    The hadronic ground state shift {epsilon}{sub 1s} and width {gamma}{sub 1s} in pionic deuterium were measured with high precision at the pion factory of the Paul Scherrer Institut (PSI), Switzerland (PSI-Experiment R-06.03). In this experiment the {pi}D(3p-1s) X-ray transition of about 3 keV was measured using a high-resolution Bragg crystal spectrometer equipped with a large-area position sensitive CCD detector. The characteristic X-radiation stems from a de-excitation cascade of the pionic atom. In order to produce an intense X-ray source, the cyclotron trap was used to stop pions in a cryogenic D{sub 2} target after winding up the pion beam in a magnetic field. The hadronic shift {epsilon}{sub 1s} is obtained from the measured transition energy by comparison to the pure electromagnetic value, where the determination of the broadening {gamma}{sub 1s} requires the precise knowledge of the spectrometer response, obtained from measurements of narrow X-ray transitions from highly ionised atoms, produced in an electron cyclotron resonance ion trap. As the formation rate is assumed to be density dependent, the {pi}D(3p-1s) X-ray energy was measured at three different D{sub 2} pressures. Another cascade process (Coulomb de-excitation) transforms the energy release of de-excitation steps into kinetic energy of the collision partners leading to a Doppler broadening of subsequent X-ray transitions. The hadronic broadening {gamma}{sub 1s} is only obtained after deconvolution of the spectrometer response function and the contributions from Doppler broadening. No energy dependence of the {pi}D(3p-1s) was found, and it is concluded that radiative de-excitation from molecular states is negligible within the experimental accuracy. Hence, the result for the shift reads {epsilon}{sub 1s} = (-2.325{+-}0.031) eV, corresponding to an accuracy of 1.3% and represents the average of the three measured densities. The uncertainty is dominated by the accuracy of the gallium K{alpha}{sub 2

  17. High-precision measurement of strong-interaction effects in pionic deuterium

    International Nuclear Information System (INIS)

    Strauch, Thomas

    2009-01-01

    The hadronic ground state shift ε 1s and width Γ 1s in pionic deuterium were measured with high precision at the pion factory of the Paul Scherrer Institut (PSI), Switzerland (PSI-Experiment R-06.03). In this experiment the πD(3p-1s) X-ray transition of about 3 keV was measured using a high-resolution Bragg crystal spectrometer equipped with a large-area position sensitive CCD detector. The characteristic X-radiation stems from a de-excitation cascade of the pionic atom. In order to produce an intense X-ray source, the cyclotron trap was used to stop pions in a cryogenic D 2 target after winding up the pion beam in a magnetic field. The hadronic shift ε 1s is obtained from the measured transition energy by comparison to the pure electromagnetic value, where the determination of the broadening Γ 1s requires the precise knowledge of the spectrometer response, obtained from measurements of narrow X-ray transitions from highly ionised atoms, produced in an electron cyclotron resonance ion trap. As the formation rate is assumed to be density dependent, the πD(3p-1s) X-ray energy was measured at three different D 2 pressures. Another cascade process (Coulomb de-excitation) transforms the energy release of de-excitation steps into kinetic energy of the collision partners leading to a Doppler broadening of subsequent X-ray transitions. The hadronic broadening Γ 1s is only obtained after deconvolution of the spectrometer response function and the contributions from Doppler broadening. No energy dependence of the πD(3p-1s) was found, and it is concluded that radiative de-excitation from molecular states is negligible within the experimental accuracy. Hence, the result for the shift reads ε 1s = (-2.325±0.031) eV, corresponding to an accuracy of 1.3% and represents the average of the three measured densities. The uncertainty is dominated by the accuracy of the gallium Kα 2 transition used for the energy calibration. From the analysis of the Doppler broadening no

  18. High precision measurement of the {eta} meson mass at COSY-ANKE

    Energy Technology Data Exchange (ETDEWEB)

    Goslawski, Paul

    2013-07-01

    Previous measurements of the {eta} meson mass performed at different experimental facilities resulted in very precise data but differ by up to more than eight standard deviations, i.e., 0.5 MeV/c. Interestingly, the difference seems to be dependent on the measuring method: two missing mass experiments, which produce the {eta} meson in the {sup 3}He{eta} final state, deviate from the recent invariant mass ones. In order to clarify this ambiguous situation a high precision mass measurement was realised at the COSY-ANKE facility. Therefore, a set of deuteron laboratory beam momenta and their associated {sup 3}He centre-of-mass momenta was measured in the dp{yields}{sup 3}HeX reaction near the {eta} production threshold. The {eta} meson was identified by the missing mass peak, whereas its mass was extracted by fixing the production threshold. The individual beam momenta were determined with a relative precision of 3 x 10{sup -5} for values just above 3 GeV/c by using a polarised deuteron beam and inducing an artificial depolarising spin resonance occurring at a well-defined frequency. The final state momenta in the two-body reaction dp{yields}{sup 3}He{eta} were investigated in detail by studying the size of the {sup 3}He momentum sphere with the forward detection system of the ANKE spectrometer. Final alignment and momentum calibration of the spectrometer was achieved by a comprehensive study of the {sup 3}He final state momenta as a function of the centre-of-mass angles, taking advantage of the full geometrical acceptance. The value obtained for the mass at COSY-ANKE m{sub {eta}}=(547.873{+-}0.005{sub stat.}{+-}0.027{sub syst.}) MeV/c{sup 2} is therefore worldwide the most precise one. This mass value is contrary to earlier missing mass experiments but it is consistent and competitive with recent invariant mass measurements, in which the meson was detected through its decay products.

  19. Influence of sulfur-bearing polyatomic species on high precision measurements of Cu isotopic composition

    Science.gov (United States)

    Pribil, M.J.; Wanty, R.B.; Ridley, W.I.; Borrok, D.M.

    2010-01-01

    An increased interest in high precision Cu isotope ratio measurements using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has developed recently for various natural geologic systems and environmental applications, these typically contain high concentrations of sulfur, particularly in the form of sulfate (SO42-) and sulfide (S). For example, Cu, Fe, and Zn concentrations in acid mine drainage (AMD) can range from 100??g/L to greater than 50mg/L with sulfur species concentrations reaching greater than 1000mg/L. Routine separation of Cu, Fe and Zn from AMD, Cu-sulfide minerals and other geological matrices usually incorporates single anion exchange resin column chromatography for metal separation. During chromatographic separation, variable breakthrough of SO42- during anion exchange resin column chromatography into the Cu fractions was observed as a function of the initial sulfur to Cu ratio, column properties, and the sample matrix. SO42- present in the Cu fraction can form a polyatomic 32S-14N-16O-1H species causing a direct mass interference with 63Cu and producing artificially light ??65Cu values. Here we report the extent of the mass interference caused by SO42- breakthrough when measuring ??65Cu on natural samples and NIST SRM 976 Cu isotope spiked with SO42- after both single anion column chromatography and double anion column chromatography. A set of five 100??g/L Cu SRM 976 samples spiked with 500mg/L SO42- resulted in an average ??65Cu of -3.50?????5.42??? following single anion column separation with variable SO42- breakthrough but an average concentration of 770??g/L. Following double anion column separation, the average SO42-concentration of 13??g/L resulted in better precision and accuracy for the measured ??65Cu value of 0.01?????0.02??? relative to the expected 0??? for SRM 976. We conclude that attention to SO42- breakthrough on sulfur-rich samples is necessary for accurate and precise measurements of ??65Cu and may require

  20. High-precision measurement of tidal current structures using coastal acoustic tomography

    Science.gov (United States)

    Zhang, Chuanzheng; Zhu, Xiao-Hua; Zhu, Ze-Nan; Liu, Wenhu; Zhang, Zhongzhe; Fan, Xiaopeng; Zhao, Ruixiang; Dong, Menghong; Wang, Min

    2017-07-01

    A high-precision coastal acoustic tomography (CAT) experiment for reconstructing the current variation in Dalian Bay (DLB) was successfully conducted by 11 coastal acoustic tomography systems during March 7-8, 2015. The horizontal distributions of tidal currents and residual currents were mapped well by the inverse method, which used reciprocal travel time data along 51 successful sound transmission rays. The semi-diurnal tide is dominant in DLB, with a maximum speed of 0.69 m s-1 at the eastern and southwestern parts near the bay mouth that gradually decreases toward the inner bay with an average velocity of 0.31 m s-1. The residual current enters the observational domain from the two flanks of the bay mouth and flows out in the inner bay. One anticyclone and one cyclone were noted inside DLB as was one cyclone at the bay mouth. The maximum residual current in the observational domain reached 0.11 m s-1, with a mean residual current of 0.03 m s-1. The upper 15-m depth-averaged inverse velocities were in excellent agreement with the moored Acoustic Doppler Current Profiler (ADCP) at the center of the bay, with a root-mean-square difference (RMSD) of 0.04 m s-1 for the eastward and northward components. The precision of the present tomography measurements was the highest thus far owing to the largest number of transmission rays ever recorded. Sensitivity experiments showed that the RMSD between CAT and moored-ADCP increased from 0.04 m s-1 to 0.08 m s-1 for both the eastward and northward velocities when reducing the number of transmission rays from 51 to 11. The observational accuracy was determined by the spatial resolution of acoustic ray in the CAT measurements. The cost-optimal scheme consisted of 29 transmission rays with a spatial resolution of acoustic ray of 2.03 √{ km2 / ray numbers } . Moreover, a dynamic analysis of the residual currents showed that the horizontal pressure gradient of residual sea level and Coriolis force contribute 38.3% and 36

  1. Evidence of 11-year solar cycles in tree rings from 1010 to 1110 AD - Progress on high precision AMS measurements

    Energy Technology Data Exchange (ETDEWEB)

    Guettler, D., E-mail: guettler@phys.ethz.ch [Laboratory of Ion Beam Physics, ETH Zurich, HPK G31, Schafmattstrasse 20, 8093 Zurich (Switzerland); Wacker, L. [Laboratory of Ion Beam Physics, ETH Zurich, HPK G31, Schafmattstrasse 20, 8093 Zurich (Switzerland); Kromer, B.; Friedrich, M. [Heidelberg Academy of Sciences, 69120 Heidelberg (Germany); Institute of Botany, University of Hohenheim, 70593 Stuttgart (Germany); Synal, H.-A. [Laboratory of Ion Beam Physics, ETH Zurich, HPK G31, Schafmattstrasse 20, 8093 Zurich (Switzerland)

    2013-01-15

    Oak tree rings from Southern Germany covering the AD 1010-1110 years have been analyzed for radiocarbon with accelerator mass spectrometry (AMS) at the laboratory at ETH Zurich. High-precision measurements with a precision down to 12 years radiocarbon age and a time resolution of 2 years aimed to identify modulations of the {sup 14}C concentration in tree ring samples caused by the 11 years solar cycles, a feature that so far is not visible in the IntCal calibration curve. Our results are in good agreement with the current calibration curve IntCal09. However, we observed an offset in radiocarbon age of 25-40 years towards older values. An evaluation of our sample preparation, that included variations of e.g.: chemicals, test glasses and processing steps did not explain this offset. The numerous measurements using the AMS-MICADAS system validated its suitability for high precision measurements with high repeatability.

  2. Detection of Stellar Pulsations in the Planet Host Star γ Cephei A by High Precision Radial Velocity Measurements

    International Nuclear Information System (INIS)

    Endl, Michael; Castanheira, Barbara G.; Cochran, William D.; Bean, Jacob L.; Wittenmyer, Robert A.; Hatzes, Artie P.

    2009-01-01

    We present a first analysis of our asteroseismology campaign on the planet host star γ Cep A. We used seven consecutive nights at the Harlan J. Smith 2.7 m telescope at McDonald Observatory to obtain 1200 highly precise radial velocity measurements. We find the star to be a multi-periodic pulsator with a frequency spacing of 15 μHz.

  3. Three years of high precision gravity measurements at the gravimetric station of Brasimone - Italy

    Directory of Open Access Journals (Sweden)

    G. Casula

    1998-06-01

    Full Text Available From August 1995 up to now, at the Enea Research Center of Brasimone, in the Italian Apennines between Bologna and Florence (Italy: 44º07'N, 11º.07'E, 890 m height, the superconducting gravimeter GWR model TT70 number T015 has been continuously recording the variation of the local gravity field, in the frame of the Global Geodynamics Project. The gravimetric laboratory, being a room of the disused nuclear power plant of Brasimone, is a very stable site, free from noise due to human activities. Data blocks of several months of continuous gravity records have been collected over a time span of three years, together with the meteorological data. The gravimeter has been calibrated at relative accuracy better than 0.3% with the aid of a mobile mass system, by imposed perturbations of the local gravity field and recording the gravimeter response. The results of this calibration technique were checked by two comparison experiments with absolute gravimeters performed during this period: the first, in May 1994 with the aid of the symmetrical rise and fall gravimeter of the Institute of Metrology Colonnetti of Turin, and the second in October 1997 involving an FG5 absolute gravimeter of the Institute de Physique du Globe of Strasbourg. The gravimeter signal was analysed to compute a high precision tidal model for Brasimone site. Starting from a set of gravimetric and atmospheric pressure data of high quality, relative to 46 months of observation, we performed the tidal analysis using Eterna 3.2 software to compute amplitudes, gravimetric factors and phases of the main waves of the Tamura catalogue. Finally a comparison experiment between two of the STS-1/VBB broadband seismometers of the MedNet project network and the gravity records relative to the Balleny Islands earthquake (March 25, 1998 were analysed to look for evidence of normal modes due to the free oscillations of the Earth.

  4. High-precision measurement of the 19Ne half-life and implications for right-handed weak currents.

    Science.gov (United States)

    Triambak, S; Finlay, P; Sumithrarachchi, C S; Hackman, G; Ball, G C; Garrett, P E; Svensson, C E; Cross, D S; Garnsworthy, A B; Kshetri, R; Orce, J N; Pearson, M R; Tardiff, E R; Al-Falou, H; Austin, R A E; Churchman, R; Djongolov, M K; D'Entremont, R; Kierans, C; Milovanovic, L; O'Hagan, S; Reeve, S; Sjue, S K L; Williams, S J

    2012-07-27

    We report a precise determination of the (19)Ne half-life to be T(1/2)=17.262±0.007 s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

  5. High-precision half-life and branching-ratio measurements for superallowed Fermi β+ emitters at TRIUMF - ISAC

    Science.gov (United States)

    Laffoley, A. T.; Dunlop, R.; Finlay, P.; Grinyer, G. F.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Blank, B.; Bouzomita, H.; Chagnon-Lessard, S.; Chester, A.; Cross, D. S.; Demand, G.; Diaz Varela, A.; Djongolov, M.; Ettenauer, S.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Glister, J.; Green, K. L.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Pearson, C. J.; Phillips, A. A.; Rand, E. T.; Starosta, K.; Sumithrarachchi, C. S.; Svensson, C. E.; Tardiff, E. R.; Thomas, J. C.; Towner, I. S.; Triambak, S.; Unsworth, C.; Williams, S. J.; Wong, J.; Yates, S. W.; Zganjar, E. F.

    2014-03-01

    A program of high-precision half-life and branching-ratio measurements for superallowed Fermi β emitters is being carried out at TRIUMF's Isotope Separator and Accelerator (ISAC) radioactive ion beam facility. Recent half-life measurements for the superallowed decays of 14O, 18Ne, and 26Alm, as well as branching-ratio measurements for 26Alm and 74Rb are reported. These results provide demanding tests of the Standard Model and the theoretical isospin symmetry breaking (ISB) corrections in superallowed Fermi β decays.

  6. High-Precision Measurement of the Ne19 Half-Life and Implications for Right-Handed Weak Currents

    Science.gov (United States)

    Triambak, S.; Finlay, P.; Sumithrarachchi, C. S.; Hackman, G.; Ball, G. C.; Garrett, P. E.; Svensson, C. E.; Cross, D. S.; Garnsworthy, A. B.; Kshetri, R.; Orce, J. N.; Pearson, M. R.; Tardiff, E. R.; Al-Falou, H.; Austin, R. A. E.; Churchman, R.; Djongolov, M. K.; D'Entremont, R.; Kierans, C.; Milovanovic, L.; O'Hagan, S.; Reeve, S.; Sjue, S. K. L.; Williams, S. J.

    2012-07-01

    We report a precise determination of the Ne19 half-life to be T1/2=17.262±0.007s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

  7. High precision measurement of the differential $W$ and $Z$ boson production cross sections with the ATLAS experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00364294; The ATLAS collaboration

    2018-01-01

    Measurements of the Drell-Yan production of $W$ and $Z/\\gamma^*$ bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at centre-of-mass energies of $7$ TeV. The measurements are performed for $W^+$, $W^-$ and $Z/\\gamma^*$ bosons integrated and differentially as a function of the boson or lepton rapidity and the $Z/\\gamma^*$ mass. Unprecedented precision is reached and strong constraints on parton distribution functions, in particular the strange quark density, are derived.

  8. The participation of ATOMKI in the G-2 international intercomparison of high precision gamma-ray spectrometry measurements

    International Nuclear Information System (INIS)

    Gaspar, A.; Lakatos, T.; Sulik, B.; Toeroek, I.

    1981-01-01

    International intercomparison had been organized by the IAEA in high precision gamma spectrometry. Five mixed-spectrum sources were prepared and sent to the participants by the IAEA for relative gamma emission rate measurements. This source type enables the whole measuring method and procedure to be tested. Measurements were carried out using two independent methods: a.) simple normalization to an additional radioactive source; b.) using a time variant pulse processor and random pulse generator for correction of dead-time and pile-up losses. The results agreed in most cases within +-1% with the IAEA results. (R.J.)

  9. Acoustic grating fringe projector for high-speed and high-precision three-dimensional shape measurements

    International Nuclear Information System (INIS)

    Yin Xuebing; Zhao Huijie; Zeng Junyu; Qu Yufu

    2007-01-01

    A new acoustic grating fringe projector (AGFP) was developed for high-speed and high-precision 3D measurement. A new acoustic grating fringe projection theory is also proposed to describe the optical system. The AGFP instrument can adjust the spatial phase and period of fringes with unprecedented speed and accuracy. Using rf power proportional-integral-derivative (PID) control and CCD synchronous control, we obtain fringes with fine sinusoidal characteristics and realize high-speed acquisition of image data. Using the device, we obtained a precise phase map for a 3D profile. In addition, the AGFP can work in running fringe mode, which could be applied in other measurement fields

  10. High-precision hyperfine structure measurement in slow atomic ion beams by collinear laser-rf double resonance

    International Nuclear Information System (INIS)

    Amarjit Sen; Childs, W.J.; Goodman, L.S.

    1987-01-01

    A new collinear laser-ion beam apparatus for slow ions (1 to 1.5 keV) has been built for measuring the hyperfine structure of metastable levels of ions with laser-rf double resonance technique. Narrow linewidths of ∼60 kHz (FWHM) have been observed for the first time in such systems. As a first application the hyperfine structure of the 4f 7 ( 8 S 0 )5d 9 D/sub J/ 0 metastable levels of /sup 151,153/Eu + has been measured with high precision. 10 refs., 8 figs

  11. Automated setup for non-tactile high-precision measurements of roundness and cylindricity using two laser interferometers

    International Nuclear Information System (INIS)

    Kühnel, M; Ullmann, V; Gerhardt, U; Manske, E

    2012-01-01

    An automated setup for non-tactile high-precision measurements of roundness and cylindricity of ring gauges is presented. The aim is to minimize classical problems of tactile and radial roundness measurements such as the error influences of the used rotary table and the work piece alignment and thus to increase the accuracy and reduce the measurement time. To achieve those aims, a double interferometer concept was chosen and combined with a measurement system for the work piece alignment, a high-precision rotary table and an automated four-axis adjustment unit. The main alignment errors of the work pieces (e.g. ring gauges) such as eccentricity and tilting are either suppressed or directly detected and consequently reduced by the automated four-axis adjustment unit. Due to the non-tactile measurement concept, higher measurement velocities are achievable and surface destruction is prevented. In combination with the contactless energy supply of the four-axis adjustment unit, the radial run of the rotary table is not affected. (paper)

  12. The development of high precision 14C measurement and its application to archaeological time-scale problems

    International Nuclear Information System (INIS)

    Pearson, G.W.

    1983-01-01

    High precision calibration curve of some 6000 years has been constructed from the measurement of contiguous 20 year samples of dendrochronologically dated Irish oak. 14 C evidence was presented using a 'wiggle' matching technique which supported the dendrochronological fixing of the BC period Irish oak chronology. Two archaeological samples were 'wiggle matched' to give a calendar age within a range of 25 years and proved that this technique is as precise as dendrochronological dating and is potentially as useful for a much wider range of samples and growth periods. (author)

  13. High-precision measurement of the wavelength of a nickel-like silver X-ray laser

    International Nuclear Information System (INIS)

    Hasegawa, Noboru; Kawachi, Tetsuya; Utsumi, Takayuki

    2004-01-01

    We conducted high-precision measurements of the wavelength of a 4d 1 S 0 →4p 1 P 1 line of a nickel-like silver X-ray laser. The Lyman series lines of hydrogen-like helium ions emitted from low-density plasmas were used as wavelength references, and the wavelength of the X-ray laser line was determined to be 13.887 nm (±0.002 nm). The experimental results were compared with Multiconfiguration Dirac-Fock calculations and were found to agree with theoretical wavelengths. (author)

  14. High precision measurement of the micro-imaging system to check repeatability of precision

    International Nuclear Information System (INIS)

    Cheng Lin; Song Li; Ma Chuntao; Luo Hongxin; Wang Jie

    2010-01-01

    The beamlines slits of Shanghai Synchrotron Radiation Facility (SSRF) are required to have a repeatability of better than 1 μm. Before the slits installation, the off-line and/or on-line repeatability measurements must be conducted. A machine vision measuring system based on high resolution CCD and adjustable high magnification lens was used in this regard. A multi-level filtering method was used to treat the imaging data. After image binarization, the imaging noises were depressed effectively by using of algebraic mean filtering, statistics median filtering,and the least square filtering. Using the subtracted image between the images before and after slit movement, an average displacement of slit blades could be obtained, and the repeatability of slit could be measured, with a resolution of 0.3 μm of the measurement system. The experimental results show that this measurement system meets the requirements for non-contact measurements to the repeatability of slits. (authors)

  15. High-precision diode-laser-based temperature measurement for air refractive index compensation.

    Science.gov (United States)

    Hieta, Tuomas; Merimaa, Mikko; Vainio, Markku; Seppä, Jeremias; Lassila, Antti

    2011-11-01

    We present a laser-based system to measure the refractive index of air over a long path length. In optical distance measurements, it is essential to know the refractive index of air with high accuracy. Commonly, the refractive index of air is calculated from the properties of the ambient air using either Ciddor or Edlén equations, where the dominant uncertainty component is in most cases the air temperature. The method developed in this work utilizes direct absorption spectroscopy of oxygen to measure the average temperature of air and of water vapor to measure relative humidity. The method allows measurement of temperature and humidity over the same beam path as in optical distance measurement, providing spatially well-matching data. Indoor and outdoor measurements demonstrate the effectiveness of the method. In particular, we demonstrate an effective compensation of the refractive index of air in an interferometric length measurement at a time-variant and spatially nonhomogeneous temperature over a long time period. Further, we were able to demonstrate 7 mK RMS noise over a 67 m path length using a 120 s sample time. To our knowledge, this is the best temperature precision reported for a spectroscopic temperature measurement. © 2011 Optical Society of America

  16. High-precision diode-laser-based temperature measurement for air refractive index compensation

    International Nuclear Information System (INIS)

    Hieta, Tuomas; Merimaa, Mikko; Vainio, Markku; Seppae, Jeremias; Lassila, Antti

    2011-01-01

    We present a laser-based system to measure the refractive index of air over a long path length. In optical distance measurements, it is essential to know the refractive index of air with high accuracy. Commonly, the refractive index of air is calculated from the properties of the ambient air using either Ciddor or Edlen equations, where the dominant uncertainty component is in most cases the air temperature. The method developed in this work utilizes direct absorption spectroscopy of oxygen to measure the average temperature of air and of water vapor to measure relative humidity. The method allows measurement of temperature and humidity over the same beam path as in optical distance measurement, providing spatially well-matching data. Indoor and outdoor measurements demonstrate the effectiveness of the method. In particular, we demonstrate an effective compensation of the refractive index of air in an interferometric length measurement at a time-variant and spatially nonhomogeneous temperature over a long time period. Further, we were able to demonstrate 7 mK RMS noise over a 67 m path length using a 120 s sample time. To our knowledge, this is the best temperature precision reported for a spectroscopic temperature measurement.

  17. High Precision Continuous and Real-Time Measurement of Atmospheric Oxygen Using Cavity Ring-Down Spectroscopy.

    Science.gov (United States)

    Kim-Hak, D.; Hoffnagle, J.; Rella, C.; Sun, M.

    2016-12-01

    Oxygen is a major and vital component of the Earth atmosphere representing about 21% of its composition. It is consumed or produced through biochemical processes such as combustion, respiration, and photosynthesis. Although atmospheric oxygen is not a greenhouse gas, it can be used as a top-down constraint on the carbon cycle. The variation observations of oxygen in the atmosphere are very small, in the order of the few ppm's. This presents the main technical challenge for measurement as a very high level of precision is required and only few methods including mass spectrometry, fuel cell, and paramagnetic are capable of overcoming it. Here we present new developments of a high-precision gas analyzer that utilizes the technique of Cavity Ring-Down Spectroscopy to measure oxygen concentration and oxygen isotope. Its compact and ruggedness design combined with high precision and long-term stability allows the user to deploy the instrument in the field for continuous monitoring of atmospheric oxygen level. Measurements have a 1-σ 5-minute averaging precision of 1-2 ppm for O2 over a dynamic range of 0-20%. We will present supplemental data acquired from our 10m tower measurements in Santa Clara, CA.

  18. High Precision UTDR Measurements by Sonic Velocity Compensation with Reference Transducer

    Directory of Open Access Journals (Sweden)

    Sam Stade

    2014-07-01

    Full Text Available An ultrasonic sensor design with sonic velocity compensation is developed to improve the accuracy of distance measurement in membrane modules. High accuracy real-time distance measurements are needed in membrane fouling and compaction studies. The benefits of the sonic velocity compensation with a reference transducer are compared to the sonic velocity calculated with the measured temperature and pressure using the model by Belogol’skii, Sekoyan et al. In the experiments the temperature was changed from 25 to 60 °C at pressures of 0.1, 0.3 and 0.5 MPa. The set measurement distance was 17.8 mm. Distance measurements with sonic velocity compensation were over ten times more accurate than the ones calculated based on the model. Using the reference transducer measured sonic velocity, the standard deviations for the distance measurements varied from 0.6 to 2.0 µm, while using the calculated sonic velocity the standard deviations were 21–39 µm. In industrial liquors, not only the temperature and the pressure, which were studied in this paper, but also the properties of the filtered solution, such as solute concentration, density, viscosity, etc., may vary greatly, leading to inaccuracy in the use of the Belogol’skii, Sekoyan et al. model. Therefore, calibration of the sonic velocity with reference transducers is needed for accurate distance measurements.

  19. High precision measurement of sin2theta/sub W/ in semi-leptonic neutrino interactions

    International Nuclear Information System (INIS)

    Guyot, C.

    1985-01-01

    The experiment has provided what is presently the most accurate measurement of sin 2 theta/sub W/. The errors are still too large for a significant test of the standard model and the measured value is in agreement with the measured values of M/sub W/ and M/sub Z/. On the other hand, this result can constrain the Grand Unified models. The standard SU(5) model predicts sin 2 theta/sub W//sup MS/ = 0.214 +/- 0.004 (the error comes from the uncertainty on Lambda/sub MS/), in very good agreement with the measured value. While this model has big problems with the proton lifetime, it could be saved by its supersymmetric extension. In the minimal SU(5) SUSY model (with 2 Higgs supermultiplets) sin 2 theta/sub W//sup MS/ = 0.233 +/- 0.004, [12] in bad agreement with the measured value. The addition of other Higgs supermultiplets increases the value of sin 2 theta/sub W/. Unless some unexpected large contribution from higher-twist terms occurs, the present measurement can already bring a significant constraint on Grand Unified models

  20. High-precision mass measurements in the realm of the deformed shell closure N=152

    Energy Technology Data Exchange (ETDEWEB)

    Eibach, Martin Andreas

    2013-12-04

    The nuclear masses reflect the sum of all interactions inside a nucleus. Their precise knowledge can be used to benchmark nuclear mass models and to gain nuclear structure information. Penning-trap mass spectrometers have proven their potential to obtain lowest uncertainties. Uniquely located at a nuclear reactor, the double Penning-trap mass spectrometer TRIGA-TRAP is dedicated to measurements in the neutron-rich region. For a gain in sensitivity a non-destructive detection system for single ion mass measurements was adopted. This includes the implementation of a narrow band-pass filter tuned to the heavy ion cyclotron frequency as well as a cryogenic low-noise amplifier. For on-line mass measurements, the laser ablation ion source was equipped with a newly developed miniature radiofrequency quadrupole trap in order to improve the extraction efficiency. A more economic use of the radioactive material enabled mass measurements using only 10{sup 15} atoms of target material. New mass measurements were performed within this work in the realm of the deformed shell closure N=152. Their implementation into the atomic-mass evaluation improved the uncertainty of more than 80 nuclides in the heavy mass region and simultaneously shifted the absolute mass of two α decay chains.

  1. High-Precision Measurements of the Bound Electron’s Magnetic Moment

    Directory of Open Access Journals (Sweden)

    Sven Sturm

    2017-01-01

    Full Text Available Highly charged ions represent environments that allow to study precisely one or more bound electrons subjected to unsurpassed electromagnetic fields. Under such conditions, the magnetic moment (g-factor of a bound electron changes significantly, to a large extent due to contributions from quantum electrodynamics. We present three Penning-trap experiments, which allow to measure magnetic moments with ppb precision and better, serving as stringent tests of corresponding calculations, and also yielding access to fundamental quantities like the fine structure constant α and the atomic mass of the electron. Additionally, the bound electrons can be used as sensitive probes for properties of the ionic nuclei. We summarize the measurements performed so far, discuss their significance, and give a detailed account of the experimental setups, procedures and the foreseen measurements.

  2. High precision slotted cavity measurement of a novel ceramic state polymer electrolyte

    Science.gov (United States)

    Quan, Wei; NurulAfsar, Mohammed

    2018-01-01

    Thin film materials are already used in a variety of microwave and higher frequency applications such as electrically tunable microwave devices, integrated circuits like MMICs, radomes, and radar absorbing coating. The determination of the dielectric properties of these films is thus of significant importance. The measurement of complex dielectric permittivity of thin films is very difficult at microwave, millimeter, and THz frequencies because both the amplitude change and phase shift are not large enough to evaluate the real part of the dielectric permittivity. A specially designed transverse slotted cavity for X-band microwave measurement has been designed and constructed to employ with a vector network analyzer to evaluate the real part of dielectric permittivity of thin films accurately and conveniently. Commercially available polymer thin films are measured to validate the methods.

  3. High Precision Measurements of W Boson Transverse Momentum at 13 TeV

    CERN Document Server

    Eppler, Drew Galen

    2018-01-01

    The precision of the transverse momentum distribution of the W-boson is crucial for reducing the uncertainty of current and future measurements of the W-boson mass. For this kind of analysis several new recoil algorithms based on particle flow objects have been recently developed. This note studies the reconstruction performances of the different hadronic recoil algorithms.

  4. Status update on the NIFFTE high precision fission cross section measurement program

    International Nuclear Information System (INIS)

    Laptev, Alexander B.; Tovesson, Fredrik; Burgett, Eric; Greife, Uwe; Grimes, Steven; Heffner, Michael D.; Hertel, Nolan E.; Hill, Tony; Isenhower, Donald; Klay, Jennifer L.; Kornilov, Nickolay; Kudo, Ryuho; Loveland, Walter; Massey, Thomas; McGrath, Chris; Pickle, Nathan; Qu, Hai; Sharma, Sarvagya; Snyder, Lucas; Thornton, Tyler; Towell, Rusty S.; Watson, Shon

    2010-01-01

    The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) program has been underway for nearly two years. The program's mission is to measure fission cross sections of the primary fissionable and fissile materials ( 235 U, 239 Pu, 238 U) as well as the minor actinides across energies from approximately 50 keV up to 20 MeV with an absolute uncertainty of less than one percent while investigating energy ranges from below an eV to 600 MeV. This basic nuclear physics data is being reinvestigated to support the next generation power plants and a fast burner reactor program. Uncertainties in the fast, resolved and unresolved resonance regions in plutonium and other transuranics are extremely large, dominating safety margins in the next generation nuclear power plants and power plants of today. This basic nuclear data can be used to support all aspects of the nuciear renaissance. The measurement campaign is utilizing a Time Projection Chamber or TPC as the tool to measure these cross sections to these unprecedented levels. Unlike traditional fission cross section measurements using time-of-flight and a multiple fission foil configurations in which fission cross sections in relation to that of 235 U are performed, the TPC project uses time-of-flight and hydrogen as the benchmark cross section. Using the switch to hydrogen, a simple, smooth cross section that can be used which removes the uncertainties associated with the resolved and unresolved resonances in 235 U.

  5. High precision optical measurement of displacement and simultaneous determinations of piezoelectric coefficients

    Science.gov (United States)

    Gamboa, Bryan M.; Malladi, Madhuri; Vadlamani, Ramya; Guo, Ruyan; Bhalla, Amar

    2016-09-01

    PZT are also well known for their applications in Micro Electrical Mechanical Systems (MEMS). It is necessary to study the piezoelectric coefficients of the materials accurately in order to design a sensor as an example, which defines their strain dependent applications. Systematic study of the electro mechanic displacement measurement was conducted and compared using a white light fiber optic sensor, a heterodyne laser Doppler vibrometer, and a homodyne laser interferometry setup. Frequency dependent measurement is conducted to evaluate displacement values well below and near the piezoelectric resonances. UHF-120 ultra-high frequency Vibrometer is used to measure the longitudinal piezoelectric displacement or x33 and the MTI 2000 FotonicTM Sensor is used to measure the transverse piezoelectric displacement or x11 over 100Hz to 2MHz. A Multiphysics Finite Element Analysis method, COMSOL, is also adopted in the study to generate a three dimensional electromechanical coupled model based on experimentally determined strains x33 and x11 as a function of frequency of the electric field applied. The full family of piezoelectric coefficients of the poled electronic ceramic PZT, d33, d31, and d15, can be then derived, upon satisfactory simulation of the COMSOL. This is achieved without the usual need of preparation of piezoelectric resonators of fundamental longitudinal, transversal, and shear modes respectively.

  6. A high precision n-p scattering measurement at 14.9 MeV

    Directory of Open Access Journals (Sweden)

    Kornilov N.V.

    2017-01-01

    Full Text Available The n-p scattering angular distribution was measured with 14.9 MeV incident neutrons using the traditional time-of-flight technique with neutron-gamma discrimination. The scattering angle varied from 20o to 65o (laboratory system in 5o incremental steps. The efficiency of the neutron detectors was measured in the energy range 2–9 MeV relative to the 252Cf-standard, and was calculated using Monte Carlo methods in the 2–14 MeV energy range. Two methods of analysis were applied for experimental and simulated data: a traditional approach with a fixed threshold, and a dynamic threshold approach. The present data agree with the ENDF/B-VII evaluation for the shape of n-p angular distribution within about 1.5%.

  7. A high precision video-electronic measuring system for use with solid state track detectors

    International Nuclear Information System (INIS)

    Schott, J.U.; Schopper, E.; Staudte, R.

    1976-01-01

    A video-electronic image analyzing system Quantimet 720 has been modified to meet the requirements of the measurement of tracks of nuclear particles in solid state track detectors with resulting improvement of precision, speed, and the elimination of subjective influences. A microscope equipped with an automatic XY stage projects the image onto the cathode of a vidicon-amplifier. Within the TV-picture generated, characterized by the coordinate XY in the specimen, we determine coordinates xy of events by setting cross lines on the screen which correspond to a digital accuracy of 0.1 μm at the position of the object. Automatic movement in Z-direction can be performed by stepping motor and measured electronically, or continously by setting electric voltage on a piezostrictive support of the objective. (orig.) [de

  8. High-Precision Half-life Measurements for the Superallowed β+ Emitter 14O

    Science.gov (United States)

    Laffoley, A. T.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Blank, B.; Bouzomita, H.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Grinyer, G. F.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Tardiff, E. R.; Thomas, J. C.; Unsworth, C.

    2014-03-01

    The half-life of 14O, a superallowed Fermi β+ emitter, has been determined via simultaneous γ and β counting experiments at TRIUMF's Isotope Separator and Accelerator facility. Following the implantation of 14O samples at the center of the 8π spectrometer, a γ counting measurement was performed by detecting the 2313 keV γ-rays emitted from the first excited state of the daughter 14N using 20 high-purity germanium (HPGe) detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned directly behind the implantation site. The results, T½(γ) = 70:632 ± 0:094 s and T½(β) = 70:610 ± 0:030 s, are consistent with one another and, together with eight previous measurements, establish a new average for the 14O half-life of T½ = 70:619 ± 0:011 s with a reduced χ2 of 0.99.

  9. High precision hyperfine measurements in Bismuth challenge bound-state strong-field QED.

    Science.gov (United States)

    Ullmann, Johannes; Andelkovic, Zoran; Brandau, Carsten; Dax, Andreas; Geithner, Wolfgang; Geppert, Christopher; Gorges, Christian; Hammen, Michael; Hannen, Volker; Kaufmann, Simon; König, Kristian; Litvinov, Yuri A; Lochmann, Matthias; Maaß, Bernhard; Meisner, Johann; Murböck, Tobias; Sánchez, Rodolfo; Schmidt, Matthias; Schmidt, Stefan; Steck, Markus; Stöhlker, Thomas; Thompson, Richard C; Trageser, Christian; Vollbrecht, Jonas; Weinheimer, Christian; Nörtershäuser, Wilfried

    2017-05-16

    Electrons bound in highly charged heavy ions such as hydrogen-like bismuth 209 Bi 82+ experience electromagnetic fields that are a million times stronger than in light atoms. Measuring the wavelength of light emitted and absorbed by these ions is therefore a sensitive testing ground for quantum electrodynamical (QED) effects and especially the electron-nucleus interaction under such extreme conditions. However, insufficient knowledge of the nuclear structure has prevented a rigorous test of strong-field QED. Here we present a measurement of the so-called specific difference between the hyperfine splittings in hydrogen-like and lithium-like bismuth 209 Bi 82+,80+ with a precision that is improved by more than an order of magnitude. Even though this quantity is believed to be largely insensitive to nuclear structure and therefore the most decisive test of QED in the strong magnetic field regime, we find a 7-σ discrepancy compared with the theoretical prediction.

  10. High-precision pose measurement method in wind tunnels based on laser-aided vision technology

    Directory of Open Access Journals (Sweden)

    Liu Wei

    2015-08-01

    Full Text Available The measurement of position and attitude parameters for the isolated target from a high-speed aircraft is a great challenge in the field of wind tunnel simulation technology. In this paper, firstly, an image acquisition method for small high-speed targets with multi-dimensional movement in wind tunnel environment is proposed based on laser-aided vision technology. Combining with the trajectory simulation of the isolated model, the reasonably distributed laser stripes and self-luminous markers are utilized to capture clear images of the object. Then, after image processing, feature extraction, stereo correspondence and reconstruction, three-dimensional information of laser stripes and self-luminous markers are calculated. Besides, a pose solution method based on projected laser stripes and self-luminous markers is proposed. Finally, simulation experiments on measuring the position and attitude of high-speed rolling targets are conducted, as well as accuracy verification experiments. Experimental results indicate that the proposed method is feasible and efficient for measuring the pose parameters of rolling targets in wind tunnels.

  11. High-Precision Half-Life and Branching Ratio Measurements for the Superallowed β+ Emitter 26Alm

    Science.gov (United States)

    Finlay, P.; Svensson, C. E.; Demand, G. A.; Garrett, P. E.; Green, K. L.; Leach, K. G.; Phillips, A. A.; Rand, E. T.; Ball, G.; Bandyopadhyay, D.; Djongolov, M.; Ettenauer, S.; Hackman, G.; Pearson, C. J.; Leslie, J. R.; Andreoiu, C.; Cross, D.; Austin, R. A. E.; Grinyer, G. F.; Sumithrarachchi, C. S.; Williams, S. J.; Triambak, S.

    2013-03-01

    High-precision half-life and branching-ratio measurements for the superallowed β+ emitter 26Alm were performed at the TRIUMF-ISAC radioactive ion beam facility. An upper limit of ≤ 15 ppm at 90% C.L. was determined for the sum of all possible non-analogue β+/EC decay branches of 26Alm, yielding a superallowed branching ratio of 100.0000+0-0.0015%. A value of T1/2 = 6:34654(76) s was determined for the 26Alm half-life which is consistent with, but 2.5 times more precise than, the previous world average. Combining these results with world-average measurements yields an ft value of 3037.58(60) s, the most precisely determined for any superallowed emitting nucleus to date. This high-precision ft value for 26Alm provides a new benchmark to refine theoretical models of isospin-symmetry-breaking effects in superallowed β decays.

  12. Performance of a high-precision calorimeter for the measurement of the antineutrino-source strength in the SOX experiment

    Energy Technology Data Exchange (ETDEWEB)

    Altenmueller, Konrad [Technische Universitaet Muenchen (Germany); Collaboration: BOREXINO-Collaboration

    2016-07-01

    A calorimeter was developed to measure the thermal power and thus the antineutrino-generation rate of a {sup 144}Ce - {sup 144}Pr antineutrino-source with < 1% overall accuracy for the SOX experiment. SOX is searching for neutrino oscillations at short baselines with the Borexino detector to investigate the existence of eV-scale sterile neutrinos. The calorimeter design is based on a copper heat exchanger with integrated water lines for the heat extraction, mounted around the source. A high precision measurement is possible thanks to an elaborate thermal insulation. In this talk, the design of the calorimeter is reviewed and results of calibration measurements are presented. The thermal insulation of the system was examined and heat losses were quantified. The methods to reconstruct the source power and the decay rate from measurements are described.

  13. Spectrophotometric high-precision seawater pH determination for use in underway measuring systems

    Directory of Open Access Journals (Sweden)

    S. Aßmann

    2011-10-01

    Full Text Available Autonomous sensors are required for a comprehensive documentation of the changes in the marine carbon system and thus to differentiate between its natural variability and anthropogenic impacts. Spectrophotometric determination of pH – a key variable of the seawater carbon system – is particularly suited to achieve precise and drift-free measurements. However, available spectrophotometric instruments are not suitable for integration into automated measurement systems (e.g. FerryBox since they do not meet the major requirements of reliability, stability, robustness and moderate cost. Here we report on the development and testing of a~new indicator-based pH sensor that meets all of these requirements. This sensor can withstand the rough conditions during long-term deployments on ships of opportunity and is applicable to the open ocean as well as to coastal waters with a complex matrix and highly variable conditions. The sensor uses a high resolution CCD spectrometer as detector connected via optical fibers to a custom-made cuvette designed to reduce the impact of air bubbles. The sample temperature can be precisely adjusted (25 °C ± 0.006 °C using computer-controlled power supplies and Peltier elements thus avoiding the widely used water bath. The overall setup achieves a measurement frequency of 1 min−1 with a precision of ±0.0007 pH units, an average offset of +0.0005 pH units to a reference system, and an offset of +0.0081 pH units to a certified standard buffer. Application of this sensor allows monitoring of seawater pH in autonomous underway systems, providing a key variable for characterization and understanding of the marine carbon system.

  14. High precision wavelength measurements of X-ray lines emitted from TS-Tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Platz, P. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Cornille, M.; Dubau, J. [Observatoire de Paris, 92 - Meudon (France)

    1996-01-01

    X-ray line spectra from highly charged impurity ions have been taken with a high-resolution Bragg-crystal spectrometer on the Tore Supra (TS) tokamak. By cross-checking the wavelengths of reference lines from the heliumlike ions Ti20 + (2.6 Angstroms) and Ar16 + (3.95 Angstroms) we first demonstrate that it is possible to measure wavelengths with a precision, {lambda}/{delta}{lambda}, of better than 50000. We than determine the wavelengths of n=3 to n=2 transitions of neonlike Ag37+ in the 4 Angstroms spectral range. (authors). 16 refs., 7 figs., 3 tabs.

  15. Searching for penguin footprints: Towards high precision CP violation measurements in the B meson systems

    CERN Document Server

    AUTHOR|(SzGeCERN)691953; Koppenburg, Patrick

    In the quark-flavour sector of the Standard Model (SM), measurements of CP violation in the $B^0_d\\to J/\\psi K_{\\rm S}^0$ and $B^0_s\\to J/\\psi \\phi$ decays play key roles in the search for signs of beyond the SM physics. For these observables, large deviations from the SM expectation have now been ruled out, but the quest for new physics still continues as the forthcoming physics runs at the LHC and KEKB super B-factory promise to reduce the experimental uncertainties even further. These prospects make it mandatory to improve the theoretical interpretation of the measurements, which is limited by uncertainties from doubly Cabibbo-suppressed penguin topologies. To get a handle on these penguin contributions, which cannot be calculated reliably in QCD, we explore a strategy that relies on the $SU(3)$ flavour symmetry of QCD and data from decays with similar dynamics. The research reported in this thesis is a shared project between theoretical and experimental particle physics. On the theoretical side, we explo...

  16. High-precision half-life measurements for the superallowed Fermi β+ emitter 14O

    Science.gov (United States)

    Laffoley, A. T.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Blank, B.; Bouzomita, H.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Grinyer, G. F.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Tardiff, E.; Thomas, J. C.; Unsworth, C.

    2013-07-01

    The half-life of the superallowed Fermi β+ emitter 14O has been determined via simultaneous direct β and γ counting experiments at TRIUMF's Isotope Separator and Accelerator (ISAC) facility. A γ-ray counting measurement was performed by detecting the 2312.6-keV γ rays emitted from an excited state of the daughter 14N following the implantation of samples at the center of the 8π γ-ray spectrometer, a spherical array of 20 high-purity germanium (HPGe) detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned behind the implantation site with a solid angle coverage of ˜20%. The results, T1/2(β)=70.610±0.030s and T1/2(γ)=70.632±0.094s, form a consistent set and, together with eight previous measurements, establish a new average for the 14O half-life of T1/2=70.619±0.011s with a reduced χ2 of 0.99.

  17. High precision flux measurements in conventional neutrino beams: the ENUBET project

    CERN Document Server

    Longhin, Andrea

    2017-01-01

    The challenges of precision neutrino physics require measurements of absolute neutrino cross sec- tions at the GeV scale with exquisite (1%) precision. This precision is presently limited to by the uncertainties on neutrino flux at the source. A reduction of this uncertainty by one order of mag- nitude can be achieved monitoring the positron production in the decay tunnel originating from the K e 3 decays of charged kaons in a sign and momentum selected narrow band beam. This novel technique enables the measurement of the most relevant cross-sections for CP violation ( ν e and ̄ ν e ) with a precision of 1% and requires a special instrumented beam-line. Such non-conventional beam-line will be developed in the framework of the ENUBET Horizon-2020 Consolidator Grant, recently approved by the European Research Council. We present the Project, the first experimen- tal results on ultra-compact calorimeters that can embedded in the instrumented decay tunnel and the advances on the simulation of the beamline. A r...

  18. High precision measurements of hyperfine structure in Tm II, N2+ and Sc II

    International Nuclear Information System (INIS)

    Mansour, N.B.; Dinneen, T.P.; Young, L.

    1988-01-01

    We have applied the technique of collinear fast-ion-beam laser spectroscopy to measure the hyperfine structure (hfs) in Sc II, Tm II and N 2 + . Laser induced fluorescence was observed from a 50 keV ion beam which was superimposed with the output of an actively stabilized ring dye laser (rms bandwidth 2 and the excited 3d4p configuration of Sc II and in the 4f 13 6s and 4f 13 5d configurations of the Tm II. The fine and hyperfine structure of N 2 + has been observed in the (0,1) and (1,2) band of B 2 Σ/sub u/ + /minus/X 2 Σ/sub g/ + system. Higher resolution measurements of the metastable 3d 2 configuration in Sc II were also made by laser-rf double resonance. The experimental results will be compared with those obtained by multiconfiguration Hartree-Fock ab-initio calculations. 15 refs., 4 figs., 5 tabs

  19. High-precision lead isotope ratio measurement by inductively coupled plasma multiple collector mass spectrometry

    International Nuclear Information System (INIS)

    Walder, A.J.; Furuta, Naoki.

    1993-01-01

    An inductively coupled plasma (ICP) ion source coupled to a magnetic sector mass analyser equipped with seven Faraday detectors has been used to measure the lead isotope ratios in solutions of Sanshiro Pond sediment collected at the University of Tokyo, airborne particulates collected at Shinjuku in Tokyo and Merck multielement standard product number 97279494. A thallium correction technique was utilized to allow a simultaneous correction for mass bias. This work followed an earlier interlaboratory comparison study of the above-mentioned solutions using ICP quadrupole mass spectrometry, and has demonstrated a considerable improvement in analytical precision. The following isotope ratio measurements were recorded. Pond sediment solution containing 82 ng ml -1 lead: 206 Pb/ 204 Pb=17.762±0.014; 206 Pb/ 207 Pb=1.1424±0.0009; 208 Pb/ 204 Pb=37.678±0.034. Airborne particulate solution containing 45 ng ml -1 lead: 206 Pb/ 204 Pb=17.969±0.006; 206 Pb/ 207 Pb=1.1528±0.0003; 208 Pb/ 204 Pb=37.915±0.021. Merck multielement standard solution containing 100 ng ml -1 lead: 206 Pb/ 204 Pb=19.255±0.015; 206 Pb/ 207 Pb=1.2238±0.0004; 208 Pb/ 204 Pb=38.476±0.021 (All errors are given as ±2 standard deviations). (author)

  20. Pion Production Measurement in NA61/SHINE Experiment for High Precision Neutrino Oscillation Experiments

    CERN Document Server

    Palczewski, Tomasz Jan

    2009-01-01

    One of physics goals of the NA61/SHINE experiment is a measurement of hadron production cross sections from proton-Carbon interactions at 31GeV/c for the T2K experiment at J-PARC. A precise knowledge of differential cross sections for pion and kaon production is of importance for improving the accuracy of neutrino flux simulations. The NA61 detector has a large angular acceptance, full coverage of the T2K phase space region, and good particle identification. In this work the analyses of negatively charged pion production are presented. Two different methods of negative pion selection and corrections for detector effects are discussed. Finally, preliminary dn/dp distributions of negatively charged pion in p+C interactions at 31 GeV/c are presented.

  1. High-precision measurements of seawater Pb isotope compositions by double spike thermal ionization mass spectrometry.

    Science.gov (United States)

    Paul, Maxence; Bridgestock, Luke; Rehkämper, Mark; van DeFlierdt, Tina; Weiss, Dominik

    2015-03-10

    A new method for the determination of seawater Pb isotope compositions and concentrations was developed, which combines and optimizes previously published protocols for the separation and isotopic analysis of this element. For isotopic analysis, the procedure involves initial separation of Pb from 1 to 2L of seawater by co-precipitation with Mg hydroxide and further purification by a two stage anion exchange procedure. The Pb isotope measurements are subsequently carried out by thermal ionization mass spectrometry using a (207)Pb-(204)Pb double spike for correction of instrumental mass fractionation. These methods are associated with a total procedural Pb blank of 28±21 pg (1sd) and typical Pb recoveries of 40-60%. The Pb concentrations are determined by isotope dilution (ID) on 50 mL of seawater, using a simplified version of above methods. Analyses of multiple aliquots of six seawater samples yield a reproducibility of about ±1 to ±10% (1sd) for Pb concentrations of between 7 and 50 pmol/kg, where precision was primarily limited by the uncertainty of the blank correction (12±4 pg; 1sd). For the Pb isotope analyses, typical reproducibilities (±2sd) of 700-1500 ppm and 1000-2000 ppm were achieved for (207)Pb/(206)Pb, (208)Pb/(206)Pb and (206)Pb/(204)Pb, (207)Pb/(204)Pb, (208)Pb/(204)Pb, respectively. These results are superior to literature data that were obtained using plasma source mass spectrometry and they are at least a factor of five more precise for ratios involving the minor (204)Pb isotope. Both Pb concentration and isotope data, furthermore, show good agreement with published results for two seawater intercomparison samples of the GEOTRACES program. Finally, the new methods were applied to a seawater depth profile from the eastern South Atlantic. Both Pb contents and isotope compositions display a smooth evolution with depth, and no obvious outliers. Compared to previous Pb isotope data for seawater, the (206)Pb/(204)Pb ratios are well correlated

  2. Multichannel FPGA based MVT system for high precision time (20 ps RMS) and charge measurement

    Science.gov (United States)

    Pałka, M.; Strzempek, P.; Korcyl, G.; Bednarski, T.; Niedźwiecki, Sz.; Białas, P.; Czerwiński, E.; Dulski, K.; Gajos, A.; Głowacz, B.; Gorgol, M.; Jasińska, B.; Kamińska, D.; Kajetanowicz, M.; Kowalski, P.; Kozik, T.; Krzemień, W.; Kubicz, E.; Mohhamed, M.; Raczyński, L.; Rudy, Z.; Rundel, O.; Salabura, P.; Sharma, N. G.; Silarski, M.; Smyrski, J.; Strzelecki, A.; Wieczorek, A.; Wiślicki, W.; Zieliński, M.; Zgardzińska, B.; Moskal, P.

    2017-08-01

    In this article it is presented an FPGA based Multi-Voltage Threshold (MVT) system which allows of sampling fast signals (1-2 ns rising and falling edge) in both voltage and time domain. It is possible to achieve a precision of time measurement of 20 ps RMS and reconstruct charge of signals, using a simple approach, with deviation from real value smaller than 10%. Utilization of the differential inputs of an FPGA chip as comparators together with an implementation of a TDC inside an FPGA allowed us to achieve a compact multi-channel system characterized by low power consumption and low production costs. This paper describes realization and functioning of the system comprising 192-channel TDC board and a four mezzanine cards which split incoming signals and discriminate them. The boards have been used to validate a newly developed Time-of-Flight Positron Emission Tomography system based on plastic scintillators. The achieved full system time resolution of σ(TOF) ≈ 68 ps is by factor of two better with respect to the current TOF-PET systems.

  3. PENTATRAP. A novel Penning-trap system for high-precision mass measurements

    Energy Technology Data Exchange (ETDEWEB)

    Doerr, Andreas

    2015-01-21

    The novel Penning-trap mass spectrometer PENTATRAP aims at mass-ratio determinations of medium-heavy to heavy ions with relative uncertainties below 10{sup -11}. From the mass ratios of certain ion species, the corresponding mass differences will be determined with sub-eV/c{sup 2} uncertainties. These mass differences are relevant for neutrino-mass experiments, a test of special relativity and tests of bound-state QED. Means to obtain the required precision are very stable trapping fields, the use of highly-charged ions produced by EBITs, a non-destructive cyclotron-frequency determination scheme employing detectors with single-ion sensitivity and a five-trap tower, that allows for measurement schemes being insensitive to magnetic field drifts. Within this thesis, part of the detection electronics was set up and tested under experimental conditions. A single-trap setup was realized. A Faraday cup in the trap tower enabled the proper adjustment of the settings of the beamline connecting the EBIT and the Penning-trap system, resulting in the first trapping of ions at PENTATRAP. A stabilization of switched voltages in the beamline and detailed studies of ion bunch characteristics allowed for reproducible loading of only a few ions. Detection of the axial oscillation of the trapped ions gave hints that in some cases, even single ions had been trapped. Furthermore, valuable conclusions about necessary modifications of the setup could be drawn.

  4. Time-separated oscillatory fields for high-precision mass measurements on short-lived Al and Ca nuclides

    CERN Document Server

    George, Simon; Blank, B.; Blaum, K.; Breitenfeldt, M.; Hager, U.; Herfurth, F.; Herlert, A.; Kellerbauer, A.; Kluge, H.J.; Kretzschmar, M.; Lunney, D.; Savreux, R.; Schwarz, Andreas S.; Schweikhard, L.; Yazidjian, C.

    2008-01-01

    High-precision Penning trap mass measurements on the stable nuclide $^{27}$Al as well as on the short-lived radionuclides $^{26}$Al and $^{38,39}$Ca have been performed by use of radio-frequency excitation with time-separated oscillatory fields, i.e. Ramsey's method, as recently introduced for the excitation of the ion motion in a Penning trap, was applied. A comparison with the conventional method of a single continuous excitation demonstrates its advantage of up to ten times shorter measurements. The new mass values of $^{26,27}$Al clarify conflicting data in this specific mass region. In addition, the resulting mass values of the superallowed $\\beta$-emitter $^{38}$Ca as well as of the groundstate of the $\\beta$-emitter $^{26}$Al$^{m}$ confirm previous measurements and corresponding theoretical corrections of the ft-values.

  5. On the source material of magmas - with special reference to Nd isotopic ratios of igneous rocks

    International Nuclear Information System (INIS)

    Shuto, Kenji

    1980-01-01

    In 1973, the Sm-Nd method was first used for the measurement of the absolute age of igneous rocks and meteorites. Subsequently in the following years, the research works by means of the Nd isotopic ratio in igneous rocks have been made strenuously in order to reveal the chemistry of the source materials of magma giving rise to the igneous rocks and further the evolution process of mantle and earth's crust. The fundamental items for the Sm-Nd method are explained. Then, the research results more important in the above connection are given. Finally, the ideas by the author concerning the source materials of magma are presented from the data available on the Nd isotopes in meteorites and igneous rocks. The following matters are described: the fundamentals of Sm-Nd method, the Nd content in seawater, the negative correlation between Nd and Sr isotopic ratios in igneous rocks, magma source materials and Nd isotopes, and considerations on magma source materials. (J.P.N.)

  6. High-precision mass measurements of nickel, copper, and gallium isotopes and the purported shell closure at N=40

    International Nuclear Information System (INIS)

    Guenaut, C.; Audi, G.; Beck, D.

    2007-01-01

    High-precision mass measurement of more than thirty neutron-rich nuclides around the Z=28 closed proton shell were performed with the triple-trap mass spectrometer ISOLTRAP at ISOLDE/CERN to address the question of a possible neutron shell closure at N=40. The results for 57,60,64-69 Ni, 65-74,76 Cu (Z=29), and 63-65,68-78 Ga (Z=31), have a relative uncertainty of the order of 10 -8 . In particular, the masses of 72-74,76 Cu have been measured for the first time. We analyse the resulting mass surface for signs of magicity, comparing the behavior of N=40 to that of known magic numbers and to mid-shell behavior. Contrary to nuclear spectroscopy studies, no indications of a shell or sub-shell closure are found for N=40. (authors)

  7. A compilation of Sr and Nd isotope data on Mexico

    International Nuclear Information System (INIS)

    Verma, S.P.; Verma, M.P.

    1986-01-01

    A compilation is given of the available Sr and Nd isotope data on Mexican volcanic-plutonic terranes which cover about one-third of Mexico's territory. The available data are arranged according to a subdivision of the Mexican territory in terms of geological provinces. Furthermore, site and province averages and standard deviations are calculated and their petrogenetic implications are pointed out. (author)

  8. High-precision 41K/39K measurements by MC-ICP-MS indicate terrestrial variability of δ41K

    Science.gov (United States)

    Morgan, Leah; Santiago Ramos, Danielle P.; Davidheiser-Kroll, Brett; Faithfull, John; Lloyd, Nicholas S.; Ellam, Rob M.; Higgins, John A.

    2018-01-01

    Potassium is a major component in continental crust, the fourth-most abundant cation in seawater, and a key element in biological processes. Until recently, difficulties with existing analytical techniques hindered our ability to identify natural isotopic variability of potassium isotopes in terrestrial materials. However, measurement precision has greatly improved and a range of K isotopic compositions has now been demonstrated in natural samples. In this study, we present a new technique for high-precision measurement of K isotopic ratios using high-resolution, cold plasma multi-collector mass spectrometry. We apply this technique to demonstrate natural variability in the ratio of 41K to 39K in a diverse group of geological and biological samples, including silicate and evaporite minerals, seawater, and plant and animal tissues. The total range in 41K/39K ratios is ca. 2.6‰, with a long-term external reproducibility of 0.17‰ (2, N=108). Seawater and seawater-derived evaporite minerals are systematically enriched in 41K compared to silicate minerals by ca. 0.6‰, a result consistent with recent findings1, 2. Although our average bulk-silicate Earth value (-0.54‰) is indistinguishable from previously published values, we find systematic δ41K variability in some high-temperature sample suites, particularly those with evidence for the presence of fluids. The δ41K values of biological samples span a range of ca. 1.2‰ between terrestrial mammals, plants, and marine organisms. Implications of terrestrial K isotope variability for the atomic weight of K and K-based geochronology are discussed. Our results indicate that high-precision measurements of stable K isotopes, made using commercially available mass spectrometers, can provide unique insights into the chemistry of potassium in geological and biological systems. 

  9. Development of a high precision dosimetry system for the measurement of surface dose rate distribution for eye applicators

    Energy Technology Data Exchange (ETDEWEB)

    Eichmann, Marion; Fluehs, Dirk; Spaan, Bernhard [Fakultaet Physik, Technische Universitaet Dortmund, D 44221 Dortmund (Germany); Klinische Strahlenphysik, Universitaetsklinikum Essen, D 45122 Essen (Germany); Fakultaet Physik, Technische Universitaet Dortmund, D 44221 Dortmund (Germany)

    2009-10-15

    Purpose: The therapeutic outcome of the therapy with ophthalmic applicators is highly dependent on the application of a sufficient dose to the tumor, whereas the dose applied to the surrounding tissue needs to be minimized. The goal for the newly developed apparatus described in this work is the determination of the individual applicator surface dose rate distribution with a high spatial resolution and a high precision in dose rate with respect to time and budget constraints especially important for clinical procedures. Inhomogeneities of the dose rate distribution can be detected and taken into consideration for the treatment planning. Methods: In order to achieve this, a dose rate profile as well as a surface profile of the applicator are measured and correlated with each other. An instrumental setup has been developed consisting of a plastic scintillator detector system and a newly designed apparatus for guiding the detector across the applicator surface at a constant small distance. It performs an angular movement of detector and applicator with high precision. Results: The measurements of surface dose rate distributions discussed in this work demonstrate the successful operation of the measuring setup. Measuring the surface dose rate distribution with a small distance between applicator and detector and with a high density of measuring points results in a complete and gapless coverage of the applicator surface, being capable of distinguishing small sized spots with high activities. The dosimetrical accuracy of the measurements and its analysis is sufficient (uncertainty in the dose rate in terms of absorbed dose to water is <7%), especially when taking the surgical techniques in positioning of the applicator on the eyeball into account. Conclusions: The method developed so far allows a fully automated quality assurance of eye applicators even under clinical conditions. These measurements provide the basis for future calculation of a full 3D dose rate

  10. Development of a high precision dosimetry system for the measurement of surface dose rate distribution for eye applicators.

    Science.gov (United States)

    Eichmann, Marion; Flühs, Dirk; Spaan, Bernhard

    2009-10-01

    The therapeutic outcome of the therapy with ophthalmic applicators is highly dependent on the application of a sufficient dose to the tumor, whereas the dose applied to the surrounding tissue needs to be minimized. The goal for the newly developed apparatus described in this work is the determination of the individual applicator surface dose rate distribution with a high spatial resolution and a high precision in dose rate with respect to time and budget constraints especially important for clinical procedures. Inhomogeneities of the dose rate distribution can be detected and taken into consideration for the treatment planning. In order to achieve this, a dose rate profile as well as a surface profile of the applicator are measured and correlated with each other. An instrumental setup has been developed consisting of a plastic scintillator detector system and a newly designed apparatus for guiding the detector across the applicator surface at a constant small distance. It performs an angular movement of detector and applicator with high precision. The measurements of surface dose rate distributions discussed in this work demonstrate the successful operation of the measuring setup. Measuring the surface dose rate distribution with a small distance between applicator and detector and with a high density of measuring points results in a complete and gapless coverage of the applicator surface, being capable of distinguishing small sized spots with high activities. The dosimetrical accuracy of the measurements and its analysis is sufficient (uncertainty in the dose rate in terms of absorbed dose to water is <7%), especially when taking the surgical techniques in positioning of the applicator on the eyeball into account. The method developed so far allows a fully automated quality assurance of eye applicators even under clinical conditions. These measurements provide the basis for future calculation of a full 3D dose rate distribution, which then can be used as input for

  11. Electron drift time in silicon drift detectors: A technique for high precision measurement of electron drift mobility

    International Nuclear Information System (INIS)

    Castoldi, A.; Rehak, P.

    1995-01-01

    This paper presents a precise absolute measurement of the drift velocity and mobility of electrons in high resistivity silicon at room temperature. The electron velocity is obtained from the differential measurement of the drift time of an electron cloud in a silicon drift detector. The main features of the transport scheme of this class of detectors are: the high uniformity of the electron motion, the transport of the signal electrons entirely contained in the high-purity bulk, the low noise timing due to the very small anode capacitance (typical value 100 fF), and the possibility to measure different drift distances, up to the wafer diameter, in the same semiconductor sample. These features make the silicon drift detector an optimal device for high precision measurements of carrier drift properties. The electron drift velocity and mobility in a 10 kΩ cm NTD n-type silicon wafer have been measured as a function of the electric field in the range of possible operation of a typical drift detector (167--633 V/cm). The electron ohmic mobility is found to be 1394 cm 2 /V s. The measurement precision is better than 1%. copyright 1995 American Institute of Physics

  12. Summary report of consultants' meeting on high-precision beta-intensity measurements and evaluations for specific PET radioisotopes

    International Nuclear Information System (INIS)

    Capote Noy, R.; Nicols, A.L.

    2009-12-01

    A summary is given of a Consultants' Meeting on 'High-precision beta-intensity measurements and evaluations for specific PET radioisotopes'. Participants assessed and reviewed the decay data for close to 50 positron-emitting radionuclides. Technical discussions are described in this report, along with the detailed recommendations and a priority list for future work. Direct positron and X-ray measurements are required to resolve a significant number of outstanding issues associated with the radionuclides reviewed. The following new measurements are recommended: gamma-ray emission probability for Cu-64, positron and Xray emission probabilities for Ni-57, Cu-62, Ga-66, As-72, Se-73, Rb-81,82m, Sr-83, Y-86 and Tc-94m. The following immediate evaluations were also recommended: Br-76 and I-120g.. Participants assessed and reviewed the decay data for close to 50 positron-emitting radionuclides. Technical discussions are described in this report, along with the detailed recommendations and a priority list for future work. Direct positron and X-ray measurements are required to resolve a significant number of outstanding issues associated with the radionuclides reviewed. The following new measurements are recommended: gamma-ray emission probability for Cu-64, positron and Xray emission probabilities for Ni-57, Cu-62, Ga-66, As-72, Se-73, Rb-81,82m, Sr-83, Y-86 and Tc-94m. The following immediate evaluations were also recommended: Br-76 and I-120g. (author)

  13. High precision measurements of 16O12C17O using a new type of cavity ring down spectrometer

    Science.gov (United States)

    Daëron, M.; Stoltmann, T.; Kassi, S.; Burkhart, J.; Kerstel, E.

    2016-12-01

    Laser absorption techniques for the measurement of isotopologue abundances in gases have been dripping into the geoscientific community over the past decade. In the field of carbon dioxide such instruments have mostly been restricted to measurements of the most abundant stable isotopologues. Distinct advantages of CRDS techniques are non-destructiveness and the ability to resolve isobaric isotopologues. The determination of low-abundance isotopologues is predominantly limited by the linewidth of the probing laser, laser jitter, laser drift and system stability. Here we present first measurements of 16O12C17O abundances using a new type of ultra-precise cavity ring down spectrometer. By the use of Optical Feedback Frequency Stabilization, we achieved a laser line width in the sub-kHz regime with a frequency drift of less than 20 Hz/s. A tight coupling with an ultra-stable ring down cavity combined with a frequency tuning mechanism which enables us to arbitrarily position spectral points (Burkart et al., 2013) allowed us to demonstrate a single-scan (2 minutes) precision of 40 ppm on the determination of the 16O12C17O abundance. These promising results imply that routine, direct, high-precision measurements of 17O-anomalies in CO2 using this non-destructive method are in reach. References:Burkart J, Romanini D, Kassi S; Optical feedback stabilized laser tuned by single-sideband modulation; Optical Letters 12:2062-2063 (2013)

  14. High-precision measurement of variations in calcium isotope ratios in urine by multiple collector inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Morgan, J.L.L.; Gordon, G.W.; Arrua, R.C.; Skulan, J.L.; Anbar, A.D.; Bullen, T.D.

    2011-01-01

    We describe a new chemical separation method to isolate Ca from other matrix elements in biological samples, developed with the long-term goal of making high-precision measurement of natural stable Ca isotope variations a clinically applicable tool to assess bone mineral balance. A new two-column procedure utilizing HBr achieves the purity required to accurately and precisely measure two Ca isotope ratios (44Ca/42Ca and 44Ca/43Ca) on a Neptune multiple collector inductively coupled plasma mass spectrometer (MC-ICPMS) in urine. Purification requirements for Sr, Ti, and K (Ca/Sr > 10000; Ca/Ti > 10000000; and Ca/K > 10) were determined by addition of these elements to Ca standards of known isotopic composition. Accuracy was determined by (1) comparing Ca isotope results for samples and standards to published data obtained using thermal ionization mass spectrometry (TIMS), (2) adding a Ca standard of known isotopic composition to a urine sample purified of Ca, and (3) analyzing mixtures of urine samples and standards in varying proportions. The accuracy and precision of δ44/42Ca measurements of purified samples containing 25 μg of Ca can be determined with typical errors less than ±0.2‰ (2σ).

  15. Ultra-High Precision Half-Life Measurement for the Superallowed &+circ; Emitter ^26Al^m

    Science.gov (United States)

    Finlay, P.; Demand, G.; Garrett, P. E.; Leach, K. G.; Phillips, A. A.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Grinyer, G. F.; Leslie, J. R.; Andreoiu, C.; Cross, D.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Djongolov, M.; Ettenauer, S.; Hackman, G.; Pearson, C. J.; Williams, S. J.

    2009-10-01

    The calculated nuclear structure dependent correction for ^26Al^m (δC-δNS= 0.305(27)% [1]) is smaller by nearly a factor of two than the other twelve precision superallowed cases, making it an ideal case to pursue a reduction in the experimental errors contributing to the Ft value. An ultra-high precision half-life measurement for the superallowed &+circ; emitter ^26Al^m has been made at the Isotope Separator and Accelerator (ISAC) facility at TRIUMF in Vancouver, Canada. A beam of ˜10^5 ^26Al^m/s was delivered in October 2007 and its decay was observed using a 4π continuous gas flow proportional counter as part of an ongoing experimental program in superallowed Fermi β decay studies. With a statistical precision of ˜0.008%, the present work represents the single most precise measurement of any superallowed half-life to date. [4pt] [1] I.S. Towner and J.C. Hardy, Phys. Rev. C 79, 055502 (2009).

  16. Rare earth element concentrations and Nd isotopes in the Southeast Pacific Ocean

    Science.gov (United States)

    Jeandel, C.; Delattre, H.; Grenier, M.; Pradoux, C.; Lacan, F.

    2013-02-01

    vertical profiles of rare earth element concentrations and Nd isotopic compositions have been measured in the remote southeast Pacific Ocean. The three stations represent contrasting environments: the oligotrophic center of the gyre (station GYR), the "transition zone" east of the South Tropical Front (station EGY), and the Peru-Chile upwelling marked by a pronounced oxygen minimum (station UPX). Rare earth concentrations display nutrient like vertical profiles except at UPX where surface waters are enriched. At this station Nd isotopic compositions are clearly more radiogenic than in the open ocean, suggesting that boundary exchange process is releasing lithogenic rare earth element from the volcanic Andes. Unexpected radiogenic values (ɛNd reaching -3.7) are also observed at 2000 m at station GYR in the Upper Circumpolar Deep Water that commonly have ɛNd values around -6. Exchange processes related to hydrothermal activity are suspected to produce this increase in ɛNd in the vicinity of the East Pacific Rise. These results provide some guidance for higher resolution studies planned in this region by the international GEOTRACES program.

  17. Evidence of 11-year solar cycles in tree rings from 1010 to 1110 AD – Progress on high precision AMS measurements

    International Nuclear Information System (INIS)

    Güttler, D.; Wacker, L.; Kromer, B.; Friedrich, M.; Synal, H.-A.

    2013-01-01

    Oak tree rings from Southern Germany covering the AD 1010–1110 years have been analyzed for radiocarbon with accelerator mass spectrometry (AMS) at the laboratory at ETH Zurich. High-precision measurements with a precision down to 12 years radiocarbon age and a time resolution of 2 years aimed to identify modulations of the 14 C concentration in tree ring samples caused by the 11 years solar cycles, a feature that so far is not visible in the IntCal calibration curve. Our results are in good agreement with the current calibration curve IntCal09. However, we observed an offset in radiocarbon age of 25–40 years towards older values. An evaluation of our sample preparation, that included variations of e.g.: chemicals, test glasses and processing steps did not explain this offset. The numerous measurements using the AMS-MICADAS system validated its suitability for high precision measurements with high repeatability.

  18. Comparison of ATLAS Tilecal MODULE No 8 high-precision metrology measurement results obtained by laser (JINR) and photogrammetric (CERN) methods

    CERN Document Server

    Batusov, V; Gayde, J C; Khubua, J I; Lasseur, C; Lyablin, M V; Miralles-Verge, L; Nessi, Marzio; Rusakovitch, N A; Sissakian, A N; Topilin, N D

    2002-01-01

    The high-precision assembly of large experimental set-ups is of a principal necessity for the successful execution of the forthcoming LHC research programme in the TeV-beams. The creation of an adequate survey and control metrology method is an essential part of the detector construction scenario. This work contains the dimension measurement data for ATLAS hadron calorimeter MODULE No. 8 (6 m, 22 tons) which were obtained by laser and by photogrammetry methods. The comparative data analysis demonstrates the measurements agreement within +or-70 mu m. It means, these two clearly independent methods can be combined and lead to the rise of a new-generation engineering culture: high-precision metrology when precision assembling of large scale massive objects. (3 refs).

  19. Comparison of ATLAS tilecal module No. 8 high-precision metrology measurement results obtained by laser (JINR) and photogrammetric (CERN) methods

    International Nuclear Information System (INIS)

    Batusov, V.; Budagov, Yu.; Gayde, J.C.

    2002-01-01

    The high-precision assembly of large experimental set-ups is of a principal necessity for the successful execution of the forthcoming LHC research programme in the TeV-beams. The creation of an adequate survey and control metrology method is an essential part of the detector construction scenario. This work contains the dimension measurement data for ATLAS hadron calorimeter MODULE No. 8 (6 m, 22 tons) which were obtained by laser and by photogrammetry methods. The comparative data analysis demonstrates the measurements agreement within ± 70 μm. It means, these two clearly independent methods can be combined and lead to the rise of a new-generation engineering culture: high-precision metrology when precision assembling of large scale massive objects

  20. Rapid subsidence in damaging sinkholes: Measurement by high-precision leveling and the role of salt dissolution

    Science.gov (United States)

    Desir, G.; Gutiérrez, F.; Merino, J.; Carbonel, D.; Benito-Calvo, A.; Guerrero, J.; Fabregat, I.

    2018-02-01

    Investigations dealing with subsidence monitoring in active sinkholes are very scarce, especially when compared with other ground instability phenomena like landslides. This is largely related to the catastrophic behaviour that typifies most sinkholes in carbonate karst areas. Active subsidence in five sinkholes up to ca. 500 m across has been quantitatively characterised by means of high-precision differential leveling. The sinkholes occur on poorly indurated alluvium underlain by salt-bearing evaporites and cause severe damage on various human structures. The leveling data have provided accurate information on multiple features of the subsidence phenomena with practical implications: (1) precise location of the vaguely-defined edges of the subsidence zones and their spatial relationships with surveyed surface deformation features; (2) spatial deformation patterns and relative contribution of subsidence mechanisms (sagging versus collapse); (3) accurate subsidence rates and their spatial variability with maximum and mean vertical displacement rates ranging from 1.0 to 11.8 cm/yr and 1.9 to 26.1 cm/yr, respectively; (4) identification of sinkholes that experience continuous subsidence at constant rates or with significant temporal changes; and (5) rates of volumetric surface changes as an approximation to rates of dissolution-induced volumetric depletion in the subsurface, reaching as much as 10,900 m3/yr in the largest sinkhole. The high subsidence rates as well as the annual volumetric changes are attributed to rapid dissolution of high-solubility salts.

  1. TIMS analysis of Sr and Nd isotopes in melt inclusions from Italian potassium-rich lavas using prototype 1013Ω amplifiers

    NARCIS (Netherlands)

    Koornneef, Janne M.; Nikogosian, Igor; van Bergen, Manfred J.; Smeets, Richard; Bouman, Claudia; Davies, Gareth R.

    2015-01-01

    Sr and Nd isotopes were determined using new thermal ionisation mass spectrometry (TIMS) techniques for a suite of 21 olivine-hosted (85-92mol% Fo) melt inclusions selected from potassic and ultra-potassic lavas from the Italian peninsula. Sr isotopes were measured using default 1011Ω resistors,

  2. Constraining Mantle Differentiation Processes with La-Ce and Sm-Nd Isotope Systematics

    Science.gov (United States)

    Willig, M.; Stracke, A.

    2016-12-01

    Cerium (Ce) and Neodymium (Nd) isotopic ratios in oceanic basalts reflect the time integrated La-Ce and Sm-Nd ratios, and hence the extent of light rare earth element element (LREE) depletion or enrichment of their mantle sources. New high precision Ce-Nd isotope data from several ocean islands define a tight array in ԑCe-ԑNd space with ԑNd = -8.2±0.4 ԑCe + 1.3±0.9 (S.D.), in good agreement with previous data [1, 2]. The slope of the ԑCe-ԑNd array and the overall isotopic range are sensitive indicators of the processes that govern the evolution of the mantle's LREE composition. A Monte Carlo approach is employed to simulate continuous mantle-crust differentiation by partial melting and recycling of crustal materials. Partial melting of mantle peridotites produces variably depleted mantle and oceanic crust, which evolve for different time periods, before the oceanic crust is recycled back into the mantle including small amounts of continental crust (GLOSS [3]). Subsequently, depleted mantle and recycled materials of variable age and composition melt, and the respective melts mix in different proportions. Mixing lines strongly curve towards depleted mantle, and tend to be offset from the data for increasingly older and more depleted mantle. Observed ԑCe-ԑNd in ridge [1] and ocean island basalts and the slope of the ԑCe-ԑNd array therefore define upper limits for the extent and age of LREE depletion preserved in mantle peridotites. Very old average mantle depletion ages (> ca. 1-2 Ga) for the bulk of the mantle are difficult to reconcile with the existing ԑCe-ԑNd data, consistent with the range of Nd-Hf-Os model ages in abyssal peridotites [4-6]. Moreover, unless small amounts of continental crust are included in the recycled material, it is difficult to reproduce the relatively shallow slope of the ԑCe-ԑNd array, consistent with constraints from the ԑNd - ԑHf mantle array [7]. [1] Makishima and Masuda, 1994 Chem. Geol. 118, 1-8. [2] Doucelance et al

  3. Calibrated high-precision 17O-excess measurements using cavity ring-down spectroscopy with laser-current-tuned cavity resonance

    Directory of Open Access Journals (Sweden)

    E. J. Steig

    2014-08-01

    Full Text Available High-precision analysis of the 17O / 16O isotope ratio in water and water vapor is of interest in hydrological, paleoclimate, and atmospheric science applications. Of specific interest is the parameter 17O excess (Δ17O, a measure of the deviation from a~linear relationship between 17O / 16O and 18O / 16O ratios. Conventional analyses of Δ17O of water are obtained by fluorination of H2O to O2 that is analyzed by dual-inlet isotope ratio mass spectrometry (IRMS. We describe a new laser spectroscopy instrument for high-precision Δ17O measurements. The new instrument uses cavity ring-down spectroscopy (CRDS with laser-current-tuned cavity resonance to achieve reduced measurement drift compared with previous-generation instruments. Liquid water and water-vapor samples can be analyzed with a better than 8 per meg precision for Δ17O using integration times of less than 30 min. Calibration with respect to accepted water standards demonstrates that both the precision and the accuracy of Δ17O are competitive with conventional IRMS methods. The new instrument also achieves simultaneous analysis of δ18O, Δ17O and δD with precision of < 0.03‰, < 0.02 and < 0.2‰, respectively, based on repeated calibrated measurements.

  4. High-precision methods and devices for in situ measurements of thermally induced aberrations in optical elements

    International Nuclear Information System (INIS)

    Zelenogorsky, Victor V.; Solovyov, Alexander A.; Kozhevatov, Ilya E.; Kamenetsky, Eugene E.; Rudenchik, Eugene A.; Palashov, Oleg V.; Silin, Dmitry E.; Khazanov, Efim A.

    2006-01-01

    An optical system that comprises two devices for remote measurements, a broadband optical interferometer and a scanning Hartmann sensor, is described. The results of simultaneous measurements with both devices and the results of numerical modeling of sample surface heating are presented

  5. Implementation of a high precision multi-measurement time-to-digital convertor on a Kintex-7 FPGA

    Science.gov (United States)

    Kuang, Jie; Wang, Yonggang; Cao, Qiang; Liu, Chong

    2018-05-01

    Time-to-digital convertors (TDCs) based on field programmable gate array (FPGA) are becoming more and more popular. Multi-measurement is an effective method to improve TDC precision beyond the cell delay limitation. However, the implementation of TDC with multi-measurement on FPGAs manufactured with 28 nm and more advanced process is facing new challenges. Benefiting from the ones-counter encoding scheme, which was developed in our previous work, we implement a ring oscillator multi-measurement TDC on a Xilinx Kintex-7 FPGA. Using the two TDC channels to measure time-intervals in the range (0 ns-30 ns), the average RMS precision can be improved to 5.76 ps, meanwhile the logic resource usage remains the same with the one-measurement TDC, and the TDC dead time is only 22 ns. The investigation demonstrates that the multi-measurement methods are still available for current main-stream FPGAs. Furthermore, the new implementation in this paper could make the trade-off among the time precision, resource usage and TDC dead time better than ever before.

  6. High-precision measurements of wetland sediment elevation. I. Recent improvements to the sedimentation--erosion table

    Science.gov (United States)

    Cahoon, D.R.; Lynch, J.C.; Hensel, P.; Boumans, R.; Perez, B.C.; Segura, B.; Day, J.W.

    2002-01-01

    The sedimentation-erosion table (SET) developed by Boumans and Day (1993) is herein renamed the surface elevation table (SET) to better reflect the conceptual view of the processes being measured. The SET was designed for making high-resolution measurements of small-scale changes in elevation of loose, unconsolidated sediments in shallow water and mudflat habitats. The SET has undergone three major improvements to increase precision and so that it can be used to measure sediment elevation in vegetated wetlands as well as shallow water habitats. The remote-release 'sliding plate' mechanism has been replaced with a single plate, collars (first 2.5 cm then 7.5 cm in length) have been attached to the plate to reduce play in the placement of the measuring pins, and the brass measuring pins have been replaced with fiberglass pins to reduce bending and consequent loss of precision. Under ideal laboratory conditions, the 95% confidence limit for individual pin measurements averaged about A? 1.4 mm (range A? 0.7 to A? 1.9 mm). These modifications have resulted in a reduction of error by about 50%.

  7. A new measurement method of actual focal spot position of an x-ray tube using a high-precision carbon-interspaced grid

    Science.gov (United States)

    Lee, H. W.; Lim, H. W.; Jeon, D. H.; Park, C. K.; Cho, H. S.; Seo, C. W.; Lee, D. Y.; Kim, K. S.; Kim, G. A.; Park, S. Y.; Kang, S. Y.; Park, J. E.; Kim, W. S.; Woo, T. H.; Oh, J. E.

    2018-06-01

    This study investigated the effectiveness of a new method for measuring the actual focal spot position of a diagnostic x-ray tube using a high-precision antiscatter grid and a digital x-ray detector in which grid magnification, which is directly related to the focal spot position, was determined from the Fourier spectrum of the acquired x-ray grid’s image. A systematic experiment was performed to demonstrate the viability of the proposed measurement method. The hardware system used in the experiment consisted of an x-ray tube run at 50 kVp and 1 mA, a flat-panel detector with a pixel size of 49.5 µm, and a high-precision carbon-interspaced grid with a strip density of 200 lines/inch. The results indicated that the focal spot of the x-ray tube (Jupiter 5000, Oxford Instruments) used in the experiment was located approximately 31.10 mm inside from the exit flange, well agreed with the nominal value of 31.05 mm, which demonstrates the viability of the proposed measurement method. Thus, the proposed method can be utilized for system’s performance optimization in many x-ray imaging applications.

  8. Strategy for the detection of vertical movements in historical environments from fast high-precision GPS measurements

    International Nuclear Information System (INIS)

    Pesci, Arianna; Casula, Giuseppe; Teza, Giordano; Bonali, Elena; Boschi, Enzo

    2012-01-01

    A continuous global positioning system station (CGPS) provides accurate coordinate time series, while episodic GPS stations (EGPSs), which operate throughout short measurement sessions, are generally used to improve the monitoring spatial density. In an urban environment, EGPSs are typically equipped with removable mounts (topographical tripod or bipod). In this paper, a method is proposed to evaluate vertical surface motions by means of differential measurements of removable mount EGPSs with respect to a nearby reference CGPS. For each day, the correct position of this CGPS is used as reference for the quick differential EGPS measurements to allow the correction of their positions. The method is applied to evaluate subsidence in the centre of Bologna, which is characterized by significant vertical movements, probably related to seasonal climatic effects, and where these movements differ significantly even among closely spaced locations. (paper)

  9. A new microscope optics for laser dark-field illumination applied to high precision two dimensional measurement of specimen displacement.

    Science.gov (United States)

    Noda, Naoki; Kamimura, Shinji

    2008-02-01

    With conventional light microscopy, precision in the measurement of the displacement of a specimen depends on the signal-to-noise ratio when we measure the light intensity of magnified images. This implies that, for the improvement of precision, getting brighter images and reducing background light noise are both inevitably required. For this purpose, we developed a new optics for laser dark-field illumination. For the microscopy, we used a laser beam and a pair of axicons (conical lenses) to get an optimal condition for dark-field observations. The optics was applied to measuring two dimensional microbead displacements with subnanometer precision. The bandwidth of our detection system overall was 10 kHz. Over most of this bandwidth, the observed noise level was as small as 0.1 nm/radicalHz.

  10. A TIMS-based method for the high precision measurements of the three-isotope potassium composition of small samples

    DEFF Research Database (Denmark)

    Wielandt, Daniel Kim Peel; Bizzarro, Martin

    2011-01-01

    A novel thermal ionization mass spectrometry (TIMS) method for the three-isotope analysis of K has been developed, and ion chromatographic methods for the separation of K have been adapted for the processing of small samples. The precise measurement of K-isotopes is challenged by the presence of ...

  11. High Precision Measurement of the Neutron Polarizabilities via Compton Scattering on Deuterium at HI γS

    Science.gov (United States)

    Sikora, Mark

    2016-09-01

    The electric (αn) and magnetic (βn) polarizabilities of the neutron are fundamental properties arising from its internal structure which describe the nucleon's response to applied electromagnetic fields. Precise measurements of the polarizabilities provide crucial constraints on models of Quantum Chromodynamics (QCD) in the low energy regime such as Chiral Effective Field Theories as well as emerging ab initio calculations from lattice-QCD. These values also contribute the most uncertainty to theoretical determinations of the proton-neutron mass difference. Historically, the experimental challenges to measuring αn and βn have been due to the difficulty in obtaining suitable targets and sufficiently intense beams, leading to significant statistical uncertainties. To address these issues, a program of Compton scattering experiments on the deuteron is underway at the High Intensity Gamma Source (HI γS) at Duke University with the aim of providing the world's most precise measurement of αn and βn. We report measurements of the Compton scattering differential cross section obtained at incident photon energies of 65 and 85 MeV and discuss the sensitivity of these data to the polarizabilities.

  12. High Precision Measurement of the Neutron Polarizabilities via Compton Scattering on Deuterium at Eγ=65 MeV

    Science.gov (United States)

    Sikora, Mark; Compton@HIGS Team

    2017-01-01

    The electric (αn) and magnetic (βn) polarizabilities of the neutron are fundamental properties arising from its internal structure which describe the nucleon's response to applied electromagnetic fields. Precise measurements of the polarizabilities provide crucial constraints on models of Quantum Chromodynamics (QCD) in the low energy regime such as Chiral Effective Field Theories as well as emerging ab initio calculations from lattice-QCD. These values also contribute the most uncertainty to theoretical determinations of the proton-neutron mass difference. Historically, the experimental challenges to measuring αn and βn have been due to the difficulty in obtaining suitable targets and sufficiently intense beams, leading to significant statistical uncertainties. To address these issues, a program of Compton scattering experiments on the deuteron is underway at the High Intensity Gamma Source (HI γS) at Duke University with the aim of providing the world's most precise measurement of αn and βn. We report measurements of the Compton scattering differential cross section obtained at an incident photon energy of 65 MeV and discuss the sensitivity of these data to the polarizabilities.

  13. High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q2

    Energy Technology Data Exchange (ETDEWEB)

    Zhan, Xiaohui [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2010-01-01

    Experiment E08-007 measured the proton elastic form factor ratio μpGE/GM in the range of Q2 = 0.3-0.7(GeV/c)2 by recoil polarimetry. Data were taken in 2008 at the Thomas Jefferson National Accelerator Facility in Virginia, USA. A 1.2 GeV polarized electron beam was scattered off a cryogenic hydrogen target. The recoil proton was detected in the left HRS in coincidence with the elasticly scattered electrons tagged by the BigBite spectrometer. The proton polarization was measured by the focal plane polarimeter (FPP). In this low Q2 region, previous measurement from Jefferson Lab Hall A (LEDEX) along with various fits and calculations indicate substantial deviations of the ratio from unity. For this new measurement, the proposed statistical uncertainty (< 1%) was achieved. These new results are a few percent lower than expected from previous world data and fits, which indicate a smaller GEp at this region. Beyond the intrinsic interest in nucleon structure, the new results also have implications in determining the proton Zemach radius and the strangeness form factors from parity violation experiments.

  14. arXiv Proceedings, High-Precision $\\alpha_s$ Measurements from LHC to FCC-ee Geneva, Switzerland, October 2-13, 2015

    CERN Document Server

    d'Enterria, David; Alekhin, S.; Banfi, A.; Bethke, S.; Blümlein, J.; Chetyrkin, K.G.; Dissertori, G.; Garcia i Tormo, X.; Hoang, A.H.; Klasen, M.; Klijnsma, T.; Kluth, S.; Kneur, J.-L.; Kniehl, B.A.; Kolodrubetz, D.W.; Kühn, J.; Mackenzie, P.; Malaescu, B.; Mateu, V.; Mihaila, L.; Moch, S.; Mönig, K.; Pérez-Ramos, R.; Pich, A.; Pires, J.; Rabbertz, K.; Salam, G.P.; Sannino, F.; Soto i Riera, J.; Srebre, M.; Stewart, I.W.

    2015-01-01

    This document provides a writeup of all contributions to the workshop on "High precision measurements of $\\alpha_s$: From LHC to FCC-ee" held at CERN, Oct. 12--13, 2015. The workshop explored in depth the latest developments on the determination of the QCD coupling $\\alpha_s$ from 15 methods where high precision measurements are (or will be) available. Those include low-energy observables: (i) lattice QCD, (ii) pion decay factor, (iii) quarkonia and (iv) $\\tau$ decays, (v) soft parton-to-hadron fragmentation functions, as well as high-energy observables: (vi) global fits of parton distribution functions, (vii) hard parton-to-hadron fragmentation functions, (viii) jets in $e^\\pm$p DIS and $\\gamma$-p photoproduction, (ix) photon structure function in $\\gamma$-$\\gamma$, (x) event shapes and (xi) jet cross sections in $e^+e^-$ collisions, (xii) W boson and (xiii) Z boson decays, and (xiv) jets and (xv) top-quark cross sections in proton-(anti)proton collisions. The current status of the theoretical and experiment...

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

    International Nuclear Information System (INIS)

    Zumberge, M.A.; Harris, R.N.; Oliver, H.W.; Sasagawa, G.S.; Ponce, D.A.

    1988-01-01

    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

  16. High-precision half-life measurements of the T =1 /2 mirror β decays 17F and 33Cl

    Science.gov (United States)

    Grinyer, J.; Grinyer, G. F.; Babo, M.; Bouzomita, H.; Chauveau, P.; Delahaye, P.; Dubois, M.; Frigot, R.; Jardin, P.; Leboucher, C.; Maunoury, L.; Seiffert, C.; Thomas, J. C.; Traykov, E.

    2015-10-01

    Background: Measurements of the f t values for T =1 /2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the f t values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T =1 /2 β+ emitters, 17F and 33Cl, in order to eliminate the half-life as the leading source of uncertainty in their f t values. Method: Half-lives of 17F and 33Cl were determined using β counting of implanted radioactive ion beam samples on a moving tape transport system at the Système de Production d'Ions Radioactifs Accélérés en Ligne low-energy identification station at the Grand Accélérateur National d'Ions Lourds. Results: The 17F half-life result, 64.347 (35) s, precise to ±0.05 % , is a factor of 5 times more precise than the previous world average. The half-life of 33Cl was determined to be 2.5038 (22) s. The current precision of ±0.09 % is nearly 2 times more precise compared to the previous world average. Conclusions: The precision achieved during the present measurements implies that the half-life no longer dominates the uncertainty of the f t values for both T =1 /2 mirror decays 17F and 33Cl.

  17. High-precision real-time 3D shape measurement based on a quad-camera system

    Science.gov (United States)

    Tao, Tianyang; Chen, Qian; Feng, Shijie; Hu, Yan; Zhang, Minliang; Zuo, Chao

    2018-01-01

    Phase-shifting profilometry (PSP) based 3D shape measurement is well established in various applications due to its high accuracy, simple implementation, and robustness to environmental illumination and surface texture. In PSP, higher depth resolution generally requires higher fringe density of projected patterns which, in turn, lead to severe phase ambiguities that must be solved with additional information from phase coding and/or geometric constraints. However, in order to guarantee the reliability of phase unwrapping, available techniques are usually accompanied by increased number of patterns, reduced amplitude of fringe, and complicated post-processing algorithms. In this work, we demonstrate that by using a quad-camera multi-view fringe projection system and carefully arranging the relative spatial positions between the cameras and the projector, it becomes possible to completely eliminate the phase ambiguities in conventional three-step PSP patterns with high-fringe-density without projecting any additional patterns or embedding any auxiliary signals. Benefiting from the position-optimized quad-camera system, stereo phase unwrapping can be efficiently and reliably performed by flexible phase consistency checks. Besides, redundant information of multiple phase consistency checks is fully used through a weighted phase difference scheme to further enhance the reliability of phase unwrapping. This paper explains the 3D measurement principle and the basic design of quad-camera system, and finally demonstrates that in a large measurement volume of 200 mm × 200 mm × 400 mm, the resultant dynamic 3D sensing system can realize real-time 3D reconstruction at 60 frames per second with a depth precision of 50 μm.

  18. High precision measurement of the hyperfine fields of substitutional and defect associated Cd in single crystalline hcp cobalt

    CERN Document Server

    Correia, J G; Melo, A A; Soares, J C

    1996-01-01

    The hyperfine fields of Cd in single crystalline hcp Co were measured after simultaneous implantation of 111mCd and 111In. High statistics measurements could be done separately for each parent isotope combining the e--g and g-g PAC techniques. The hyperfine coupling constants wL(CdCo)=422.8(1) Mrad/s and w0(CdCo)=6.14(11) Mrad/s are determined for Cd probes in undisturbed substitutional sites. Several defect associated sites in the hcp Co lattice are clearly seen in the data. Most of the radiation damage created by the ion implantation anneals out at temperatures below 503 K, with only one dominating component surviving at this temperature. This defect is assigned as a probe atom in an interstitial site, surrounded by a vacancy tetrahedron. The corresponding magnetic field and electric field gradient are collinear with the c-axis of the Co lattice, and the respective coupling constants are wL(defect)= 216.7(2) Mrad/s and w0(defect)= 45.3(6) Mrad/s.

  19. High precision measurement by mass spectrometry of isotopic ratios δ13C and δ18O of carbon dioxide

    International Nuclear Information System (INIS)

    Bourg, Chr.; Ciais, Ph.

    1998-02-01

    Carbon dioxide (CO 2 ) is the second natural greenhouse gas in the Earth's atmosphere, after vapor water. Its concentration levels have been increasing by 25% due to human activities over the past 200 years, thus increasing the radiative forcing at the surface and potentially including major climate change for the next centuries. It is of primary importance to better quantify the role of carbon contained into the oceans and the land biota in moderating the anthropic perturbation. To do so, 13 C and 18 O isotopes are unique tools which allow to estimate indirectly the terrestrial CO 2 fluxes based on atmospheric measurements. The present reports describes the experimental set-up used at the CFR-LMCE laboratory to measure the 13 C and 18 O natural abundance in atmospheric carbon dioxide. This technique requires high levels of both precision and accuracy because the geochemical signal nevertheless consists of very small changes in isotopic composition (on the order of 0.01 permits). Also, given the large number of samples to analyses routinely, it must be run in an automatic mode. Our experiment design consists of 'extraction line' where CO 2 is separated cryogenically from the air, which is coupled to a (Finnigan MAT 252) mass spectrometer. (authors)

  20. Identification of E6-generated Z' from combined CHARM II, LEP 1, SLC high-precision measurements

    International Nuclear Information System (INIS)

    Lynn, B.W.; Renard, F.M.; Verzegnassi, C.

    1988-01-01

    We show that a combined analysis of three specific longitudinal polarization asymmetries in electron-positron annihilation on Z 0 resonance, of the mass ratio M w /M z and of the neutrino-electron neutral cross-section ratio, which could be measured in the near future at SLC, LEP, ACOL and CHARM II, would lead to a well-defined identification of a single new E 6 -generated Z'. In particular, it might be possible to disentangle a superstring-inspired model from other currently considered possibilities down to values of the mixing angle vertical strokeθ η vertical stroke = 0.02 and, at the same time, to fix the mass ratio ε = M Z 2 /Msub(Z') 2 with known accuracy. (orig.)

  1. A high precision mass spectrometry method for measuring O2/N2 ratios and CO2 concentrations in air

    International Nuclear Information System (INIS)

    Marca, A.D.; Dennis, P.F.; Etchells, A.

    2002-01-01

    A full, detailed understanding of the global carbon budget is needed for robust modelling of global climate and environmental change. Since the industrial revolution the carbon cycle has been shifted from a steady state in which removal of CO 2 from the atmosphere through photosynthesis is balanced by its addition through respiration. Currently increased respiration due to deforestation, modern agricultural practises and the burning of fossil fuels dominates photosynthesis resulting in modern atmospheric CO 2 concentrations some 32% higher than the year 1800 levels. However, the CO 2 concentration rises are lower than expected from known fossil fuel combustion inventories. A significant proportion of the excess CO 2 is taken up by the oceans, however a missing carbon sink must still be invoked to account for the difference between measured and expected CO 2 rises. A global greening as a result of increased photosynthesis is required to close the circle

  2. High-Precision Measurement of Eu/Eu* in Geological Glasses via LA-ICP-MS Analysis

    Science.gov (United States)

    Tang, Ming; McDonough, William F.; Arevalo, Ricardo, Jr.

    2014-01-01

    Elemental fractionation during laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis has been historically documented between refractory and volatile elements. In this work, however, we observed fractionation between light rare earth elements (LREEs) and heavy rare earth elements (HREEs) when using ablation strategies involving large spot sizes (greater than 100 millimeters) and line scanning mode. In addition: (1) ion yields decrease when using spot sizes above 100 millimeters; (2) (Eu/Eu*)(sub raw) (i.e. Europium anomaly) positively correlates with carrier gas (He) flow rate, which provides control over the particle size distribution of the aerosol reaching the ICP; (3) (Eu/Eu*)(sub raw) shows a positive correlation with spot size, and (4) the changes in REE signal intensity, induced by the He flow rate change, roughly correlate with REE condensation temperatures. The REE fractionation is likely driven by the slight but significant difference in their condensation temperatures. Large particles may not be completely dissociated in the ICP and result in preferential evaporation of the less refractory LREEs and thus non-stoichiometric particle-ion conversion. This mechanism may also be responsible for Sm-Eu-Gd fractionation as Eu is less refractory than Sm and Gd. The extent of fractionation depends upon the particle size distribution of the aerosol, which in turn is influenced by the laser parameters and matrix. Ablation pits and lines defined by low aspect ratios produce a higher proportion of large particles than high aspect ratio ablation, as confirmed by measurements of particle size distribution in the laser induced aerosol. Therefore, low aspect ratio ablation introduces particles that cannot be decomposed and/or atomized by the ICP and thus results in exacerbated elemental fractionation. Accurate quantification of REE concentrations and Eu/Eu* requires reduction of large particle production during laser ablation. For the reference

  3. High Precision Stable Isotope Measurements of Caribic Aircraft CO{sub 2} Samples: Global Distribution and Exchange with the Biosphere

    Energy Technology Data Exchange (ETDEWEB)

    Assonov, S. S. [Max Planck Institute for Chemistry, Mainz (Germany); Joint Research Centre, Institute for Reference Materials and Measurements (JRC-IRMM), European Commission, Geel (Belgium); Brenninkmeijer, C. A.M.; Schuck, T. J. [Max Planck Institute for Chemistry, Mainz (Germany); Taylor, P. [Joint Research Centre, Institute for Reference Materials and Measurements (JRC-IRMM), European Commission, Geel (Belgium)

    2013-07-15

    In 2007-2009 JRC-IRMM, in collaboration with the project CARIBIC (Civil Aircraft for Regular Investigation of the atmosphere Based on an Instrument Container, www.caribicatmospheric. com), conducted systematic measurements aimed to study the global distribution of CO{sub 2} isotopic composition. A large data set for the upper troposphere-lowermost stratosphere and free troposphere was obtained. For the first time it is demonstrated how CO{sub 2} isotope signals reflect global scale variability in air mass origin. Tight correlations observed arise either from stratosphere/troposphere mixing or from mixing of background air and air masses affected by CO{sub 2} sources and sinks, over long distances and throughout the seasons. The high quality {delta}{sup 18}O(CO{sub 2}) data prove to be a useful tracer reflecting long range CO{sub 2} transport and also CO{sub 2} exchange with land biosphere and soils. The data provide a benchmark for future comparisons and are available for modelling studies. (author)

  4. High-precision measurements of the compressibility of chalcogenide glasses at a hydrostatic pressure up to 9 GPa

    Energy Technology Data Exchange (ETDEWEB)

    Brazhkin, V. V., E-mail: brazhkin@hppi.troitsk.ru [Vereshchagin Institute of High-Pressure Physics (Russian Federation); Bychkov, E. [Universite du Littoral, LPCA, UMR 8101 CNRS (France); Tsiok, O. B. [Vereshchagin Institute of High-Pressure Physics (Russian Federation)

    2016-08-15

    The volumes of glassy germanium chalcogenides GeSe{sub 2}, GeS{sub 2}, Ge{sub 17}Se{sub 83}, and Ge{sub 8}Se{sub 92} are precisely measured at a hydrostatic pressure up to 8.5 GPa. The stoichiometric GeSe{sub 2} and GeS{sub 2} glasses exhibit elastic behavior in the pressure range up to 3 GPa, and their bulk modulus decreases at pressures higher than 2–2.5 GPa. At higher pressures, inelastic relaxation processes begin and their intensity is proportional to the logarithm of time. The relaxation rate for the GeSe{sub 2} glasses has a pronounced maximum at 3.5–4.5 GPa, which indicates the existence of several parallel structural transformation mechanisms. The nonstoichiometric glasses exhibit a diffuse transformation and inelastic behavior at pressures above 1–2 GPa. The maximum relaxation rate in these glasses is significantly lower than that in the stoichiometric GeSe{sub 2} glasses. All glasses are characterized by the “loss of memory” of history: after relaxation at a fixed pressure, the further increase in the pressure returns the volume to the compression curve obtained without a stop for relaxation. After pressure release, the residual densification in the stoichiometric glasses is about 7% and that in the Ge{sub 17}Se{sub 83} glasses is 1.5%. The volume of the Ge{sub 8}Se{sub 92} glass returns to its initial value within the limits of experimental error. As the pressure decreases, the effective bulk moduli of the Ge{sub 17}Se{sub 83} and Ge{sub 8}Se{sub 92} glasses coincide with the moduli after isobaric relaxation at the stage of increasing pressure, and the bulk modulus of the stoichiometric GeSe{sub 2} glass upon decreasing pressure noticeably exceeds the bulk modulus after isobaric relaxation at the stage of increasing pressure. Along with the reported data, our results can be used to draw conclusions regarding the diffuse transformations in glassy germanium chalcogenides during compression.

  5. An improved method for high precision measurement of chromium isotopes using double spike MC-ICP-MS

    Science.gov (United States)

    Zhu, J.; Wu, G. L.; Wang, X.; Zhang, L. X.; Han, G.

    2017-12-01

    Chormium(Cr) isotopes have been used to trace pollution processes and reconstruct paleo-redox conditions. However, the precise determination of Cr isotopes has still been challenged due to difficulties in purifying Cr from samples with low Cr content and complex matrices. Here we report an improved four-step column chromatographic procedure to separate Cr from matrix elements. Firstly, Cr in sample solution was mixed with 50Cr-54Cr double spike (the optimized 54Crspike/52Crsample = 0.4 and (50Cr/54Cr)spike = 1.3:1) was completely converted into Cr (III) in 8.5mol/L HCl and loaded onto 2ml of AG50W-X8(200-400m) resin conditioned with 11 mol/L HCl. The 2.65ml of eluent was adjusted to 4.5ml of 6mol/L HCl and immediately loaded onto a Bio-Rad column filled with 2ml of AG1-X8 anion resin (100-200m). These two steps can remove at least 99% of Ca, Fe and most matrix elements. Secondly, the 7.5ml of eluent was dried down and dissolved in 0.1ml of 0.5mol/L HNO3.before adding 2ml 4mol/L HF, which was then loaded onto 1ml of AG1-X8 anion resin (100-200m) to remove Ti and V. Finally, sample was dissolved in 0.1ml of 0.5 mol/L HNO3 and oxidized by 0.5mL 0.2 mol/L (NH4)2S2O8 and 4.4mL H2O, which was then centrifuged to remove Mn oxide, and supernatant was loaded onto AG1-X8 resin to remove SO42-, Ni, Al, Na and some Mg using 8ml H2O and 3ml 2mol/L HCl. Cr was eluted by 2 mol/L HNO3 containing 5% H2O2 and the dried Cr was dissolved in 3% HNO3for isotopic analysis. The total yield to Cr is great than 80% even for samples with low Cr content. Chromium isotopes was measured on a Neptune plus MC-ICP-MS in China University of Geosciences(Beijing). Using our improved method, the δ53/52CrSRM979 values of USGS reference materials BHVO-2, BCR-2 and SGR-1b are -0.12±0.06‰(n=15), -0.09±0.06‰ (n=5), and 0.30±0.06‰ (n=12), respectively, which agree well with previously reported values. The δ53/52CrSRM979 of carbonaceous shale CP0-1 and CP0-12 collected from Hubei, China are 2.05

  6. Study of properties of helium-based gas mixtures for use of low momentum and high precision measurement in drift chambers

    International Nuclear Information System (INIS)

    Chen Chang; Zhang Qinjian; Ma Jimao; Huang Xiuping; Yi Kai; Zheng Shuchen

    1998-01-01

    Measured drift velocities using an uniform field drift chamber and multiplication factors obtained with proportional tubes in He-based gas mixtures He + CH 4 (80/20, 70/30) and He + iC 4 H 10 (85/15, 80/20, 70/30) are reported. The results are good agreement with calculations by Garfield Code. The Saturated drift velocity is V d ≅ 2.7 cm/μs and multiplication factor of M ≅ 10 4 -10 5 at certain working voltage is manageable in He/CH 4 (80/20) gas mixture, and it is good candidate of working gas for use of low momentum and high precision measurement in the drift chambers

  7. Otolith oxygen isotopes measured by high-precision secondary ion mass spectrometry reflect life history of a yellowfin sole (Limanda aspera).

    Science.gov (United States)

    Matta, Mary Elizabeth; Orland, Ian J; Ushikubo, Takayuki; Helser, Thomas E; Black, Bryan A; Valley, John W

    2013-03-30

    The oxygen isotope ratio (δ(18)O value) of aragonite fish otoliths is dependent on the temperature and the δ(18)O value of the ambient water and can thus reflect the environmental history of a fish. Secondary ion mass spectrometry (SIMS) offers a spatial-resolution advantage over conventional acid-digestion techniques for stable isotope analysis of otoliths, especially given their compact nature. High-precision otolith δ(18)O analysis was conducted with an IMS-1280 ion microprobe to investigate the life history of a yellowfin sole (Limanda aspera), a Bering Sea species known to migrate ontogenetically. The otolith was cut transversely through its core and one half was roasted to eliminate organic contaminants. Values of δ(18)O were measured in 10-µm spots along three transects (two in the roasted half, one in the unroasted half) from the core toward the edge. Otolith annual growth zones were dated using the dendrochronology technique of crossdating. Measured values of δ(18)O ranged from 29.0 to 34.1‰ (relative to Vienna Standard Mean Ocean Water). Ontogenetic migration from shallow to deeper waters was reflected in generally increasing δ(18)O values from age-0 to approximately age-7 and subsequent stabilization after the expected onset of maturity at age-7. Cyclical variations of δ(18)O values within juvenile otolith growth zones, up to 3.9‰ in magnitude, were caused by a combination of seasonal changes in the temperature and the δ(18)O value of the ambient water. The ion microprobe produced a high-precision and high-resolution record of the relative environmental conditions experienced by a yellowfin sole that was consistent with population-level studies of ontogeny. Furthermore, this study represents the first time that crossdating has been used to ensure the dating accuracy of δ(18)O measurements in otoliths. Copyright © 2013 John Wiley & Sons, Ltd.

  8. High-precision mass measurements of neutron-deficient Tl isotopes at ISOLTRAP and the development of an ultra-stable voltage source for the PENTATRAP experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Christine

    2015-01-14

    Atomic masses and hence binding energies of nuclides are of great importance for studies of nuclear structure since they reflect all effective interactions in a nucleus. Within this thesis the masses of seven nuclides, namely {sup 194}Au, {sup 194}Hg, {sup 190,193,198}Tl and {sup 202,208}Pb, were determined at the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The thallium region in the chart of isotopes is of special interest due to the occurrence of nuclear structure effects like low-lying isomers, level inversion, shape coexistence and deformations. These effects are investigated by applying finite-difference mass formulas, such as the two-neutron separation energies or the so-called empirical pairing gaps. The second topic addressed within the present thesis is an ultra-stable voltage source, called StaReP (Stable Reference for Penning Trap Experiments), which was developed at the Max-Planck-Institut fuer Kernphysik. It is one of the key components of the high-precision mass spectrometer PENTATRAP, containing a tower of five Penning traps. A 25-channel voltage source with a relative stability of few 10{sup -8} over a period of 10 minutes in the range of 0 to -100V is mandatory for PENTATRAP aiming for mass measurements with relative mass uncertainties of ≤ 10{sup -11}. Mass values with such a high precision allow for stringent tests of quantum electrodynamics in strong electric fields, testing Einstein's mass-energy relation E = mc{sup 2} as well as measurements of decay energies (Q-values) with applications in neutrino physics.

  9. A High-Precision RF Time-of-Flight Measurement Method based on Vernier Effect for Localization of Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sang-il KO

    2011-12-01

    Full Text Available This paper presents the fundamental principles of a high-precision RF time-of-flight (ToF measurement method based on the vernier effect, which enables the improvement of time measurement resolution, for accurate distance measurement between sensor nodes in wireless sensor networks. Similar to the two scales of the vernier caliper, two heterogeneous clocks are employed to induce a new virtual time resolution that is much finer than clocks’ intrinsic time resolution. Consecutive RF signal transmission and sensing using two heterogeneous clocks generates a unique sensing pattern for the RF ToF, so that the size of the RF ToF can be estimated by comparing the measured sensing pattern with the predetermined sensing patterns for the RF ToF. RF ToF measurement experiments using this heterogeneous clock system, which has low operating frequencies of several megahertz, certify the proposed RF ToF measurement method through the evaluation of the measured sensing patterns with respect to an RF round-trip time of several nanoseconds.

  10. Highly precise (liquid + liquid) equilibrium and heat capacity measurements near the critical point for [Bmim][BF4] + 1H, 1H, 2H, 2H perfluoroctanol

    International Nuclear Information System (INIS)

    Pérez-Sánchez, G.; Troncoso, J.; Losada-Pérez, P.; Méndez-Castro, P.; Romaní, L.

    2013-01-01

    Highlights: • Highly precise liquid–liquid curves for [Bmim][BF 4 ] + perfluoroctanol are reported. • Critical behavior of heat capacity for the same system was also characterized. • In contrast to previous results, no coulombic/solvophobic crossover for coexistence curve diameter was found. • The system criticality shows characteristics both solvophobic and coulombic. -- Abstract: Liquid + liquid equilibrium of the system [Bmim][BF 4 ] + 1H, 1H, 2H, 2H perfluoroctanol using a highly precise methodology based on refractive index measurements was experimentally determined. In addition, isobaric heat capacity near the critical point was obtained. The performance of the new refractive index set-up was successfully checked against the coexistence curve of the system dimethyl carbonate + decane, since highly accurate data are available in the literature. The choice of [Bmim][BF 4 ] + 1H, 1H, 2H, 2H perfluoroctanol was motivated by a previous experimental work, whose results suggest that this system could present characteristics of both solvophobic and coulombic behavior, which are the two categories to which an ionic system can belong. Although this was previously observed for other ionic systems, this mixture presented a very striking feature: the diameter of the coexistence curve seemed to change its criticality in the studied temperature range, from solvophobic far away to coulombic close to the critical point. The results of this work reveal that, in fact, [Bmim][BF 4 ] + 1H, 1H, 2H, 2H perfluoroctanol presents characteristics of both solvophobic and coulombic criticality, but no evidence of the observed crossover over the experimental temperature range has been found

  11. High-precision Pb isotopic measurements of teeth and environmental samples from Sofia (Bulgaria): insights for regional lead sources and possible pathways to the human body

    Science.gov (United States)

    Kamenov, George D.

    2008-08-01

    High-precision Pb isotopic measurements on teeth and possible sources in a given area can provide important insights for the lead (Pb) sources and pathways in the human body. Pb isotopic analyses on soils from the area of Sofia, Bulgaria show that Pb is contributed by three end-members represented by two natural sources and leaded gasoline. Sequential leaching experiments reveal that the alumosilicate fraction of the soils is mainly controlled by natural Pb derived from two mountain massifs bordering the city. Around 1/3 to a half of the Pb in the soil leachates, however, can be explained by contamination from leaded gasoline. Contemporary teeth from Sofia residents show very similar Pb isotopic compositions to the soil leachates, also indicating that around 1/3 to a half of the Pb can be explained by derivation from leaded gasoline. The remarkable isotopic similarities between the teeth and the most labile fractions of the local soils suggest that the lead can be derived from the latter. Pb incorporation in the human body via soil-plant-human or soil-plant-animal-human chains is unlikely due to the fact that no significant farming occurs in the city area. The isotopic compositions of the local soil labile fractions can be used as approximation of the bioaccessible lead for humans. Considering all possible scenarios it appears that soil and/or soil-born dust inhalation and/or ingestion is the most probable pathway for incorporation of local soil lead in the local population. The high-precision Pb isotope data presented in this work indicate that apparently the local soil is what plays major role in the human Pb exposure.

  12. Development of a versatile sample preparation method and its application for rare-earth pattern and Nd isotope ratio analysis in nuclear forensics

    International Nuclear Information System (INIS)

    Krajko, J.

    2015-01-01

    An improved sample preparation procedure for trace-levels of lanthanides in uranium-bearing samples was developed. The method involves a simple co-precipitation using Fe(III) carrier in ammonium carbonate medium to remove the uranium matrix. The procedure is an effective initial pre-concentration step for the subsequent extraction chromatographic separations. The applicability of the method was demonstrated by the measurement of REE pattern and 143 Nd/ 144 Nd isotope ratio in uranium ore concentrate samples. (author)

  13. High precision mass measurements of thermalized relativistic uranium projectile and fission fragments with a multiple-reflection time-of-flight mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Ayet San Andres, Samuel [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Justus Liebig Universitaet, Giessen (Germany); Collaboration: FRS Ion Catcher-Collaboration

    2016-07-01

    At the FRS Ion Catcher at GSI, a relativistic beam of {sup 238}U at 1GeV/u was used to produce fission and projectile fragments on a beryllium target. The ions were separated in-flight at the FRS, thermalized in a cryogenic stopping cell and transferred to a multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) where high precision mass measurements were performed. The masses of several fission and projectile fragments were measured (including short-lived nuclei with half-lives down to 18 ms) and the possibility of tailoring an isomerically clean beam for other experiments was demonstrated. With the demonstrated performance of the MR-TOF-MS and the expected production rates of exotic nuclei far from stability at the next-generation facilities such as FAIR, novel mass measurements of nuclei close to the neutron drip line will be possible and key information for understanding the r-process will be available. The results from the last experiment and an outlook of possible future mass measurements close to the neutron drip line at FAIR with the MR-TOF-MS are presented.

  14. Sr-Nd isotope systematics of xenoliths in Cenozoic volcanic rocks from SW Japan

    International Nuclear Information System (INIS)

    Kagami, Hiroo; Iwata, Masatoshi; Iizumi, Shigeru; Nureki, Terukazu.

    1993-01-01

    Based on new and previously published Sr and Nd isotope data, we examined the petrogenetic relationship between deep crust- and upper mantle-derived xenoliths contained in Cenozoic volcanic rocks and Cretaceous-Paleogene granitoid rocks in SW Japan. The deep crust- and upper mantle-derived mafic to ultramafic xenoliths contained in Cenozoic volcanic rocks from SW Japan have comparable initial Sr and Nd isotope ratios to the Cretaceous-Paleogene granitoid rocks in their respective districts. This may suggest that these xenoliths were genetically related to the Cretaceous-Paleogene granitoid rocks in SW Japan, and that regional variations in Sr and Nd isotope ratios observed in the granitoid rocks are attributed to differences in the geochemistry of the magma sources. (author)

  15. The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium

    Energy Technology Data Exchange (ETDEWEB)

    Ketelaer, Jens

    2010-06-14

    The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium: Nuclear masses are an important quantity to study nuclear structure since they reflect the sum of all nucleonic interactions. Many experimental possibilities exist to precisely measure masses, out of which the Penning trap is the tool to reach the highest precision. Moreover, absolute mass measurements can be performed using carbon, the atomic-mass standard, as a reference. The new double-Penning trap mass spectrometer TRIGA-TRAP has been installed and commissioned within this thesis work, which is the very first experimental setup of this kind located at a nuclear reactor. New technical developments have been carried out such as a reliable non-resonant laser ablation ion source for the production of carbon cluster ions and are still continued, like a non-destructive ion detection technique for single-ion measurements. Neutron-rich fission products will be available by the reactor that are important for nuclear astrophysics, especially the r-process. Prior to the on-line coupling to the reactor, TRIGA-TRAP already performed off-line mass measurements on stable and long-lived isotopes and will continue this program. The main focus within this thesis was on certain rare-earth nuclides in the well-established region of deformation around N {proportional_to} 90. Another field of interest are mass measurements on actinoids to test mass models and to provide direct links to the mass standard. Within this thesis, the mass of {sup 241}Am could be measured directly for the first time. (orig.)

  16. The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium

    International Nuclear Information System (INIS)

    Ketelaer, Jens

    2010-01-01

    The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium: Nuclear masses are an important quantity to study nuclear structure since they reflect the sum of all nucleonic interactions. Many experimental possibilities exist to precisely measure masses, out of which the Penning trap is the tool to reach the highest precision. Moreover, absolute mass measurements can be performed using carbon, the atomic-mass standard, as a reference. The new double-Penning trap mass spectrometer TRIGA-TRAP has been installed and commissioned within this thesis work, which is the very first experimental setup of this kind located at a nuclear reactor. New technical developments have been carried out such as a reliable non-resonant laser ablation ion source for the production of carbon cluster ions and are still continued, like a non-destructive ion detection technique for single-ion measurements. Neutron-rich fission products will be available by the reactor that are important for nuclear astrophysics, especially the r-process. Prior to the on-line coupling to the reactor, TRIGA-TRAP already performed off-line mass measurements on stable and long-lived isotopes and will continue this program. The main focus within this thesis was on certain rare-earth nuclides in the well-established region of deformation around N ∝ 90. Another field of interest are mass measurements on actinoids to test mass models and to provide direct links to the mass standard. Within this thesis, the mass of 241 Am could be measured directly for the first time. (orig.)

  17. Pile-up corrections for high-precision superallowed β decay half-life measurements via γ-ray photopeak counting

    Science.gov (United States)

    Grinyer, G. F.; Svensson, C. E.; Andreoiu, C.; Andreyev, A. N.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Chakrawarthy, R. S.; Finlay, P.; Garrett, P. E.; Hackman, G.; Hyland, B.; Kulp, W. D.; Leach, K. G.; Leslie, J. R.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Sarazin, F.; Schumaker, M. A.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Williams, S. J.; Wong, J.; Wood, J. L.; Zganjar, E. F.

    2007-09-01

    A general technique that corrects γ-ray gated β decay-curve data for detector pulse pile-up is presented. The method includes corrections for non-zero time-resolution and energy-threshold effects in addition to a special treatment of saturating events due to cosmic rays. This technique is verified through a Monte Carlo simulation and experimental data using radioactive beams of Na26 implanted at the center of the 8π γ-ray spectrometer at the ISAC facility at TRIUMF in Vancouver, Canada. The β-decay half-life of Na26 obtained from counting 1809-keV γ-ray photopeaks emitted by the daughter Mg26 was determined to be T=1.07167±0.00055 s following a 27σ correction for detector pulse pile-up. This result is in excellent agreement with the result of a previous measurement that employed direct β counting and demonstrates the feasibility of high-precision β-decay half-life measurements through the use of high-purity germanium γ-ray detectors. The technique presented here, while motivated by superallowed-Fermi β decay studies, is general and can be used for all half-life determinations (e.g. α-, β-, X-ray, fission) in which a γ-ray photopeak is used to select the decays of a particular isotope.

  18. High Precision, Absolute Total Column Ozone Measurements from the Pandora Spectrometer System: Comparisons with Data from a Brewer Double Monochromator and Aura OMI

    Science.gov (United States)

    Tzortziou, Maria A.; Herman, Jay R.; Cede, Alexander; Abuhassan, Nader

    2012-01-01

    We present new, high precision, high temporal resolution measurements of total column ozone (TCO) amounts derived from ground-based direct-sun irradiance measurements using our recently deployed Pandora single-grating spectrometers. Pandora's small size and portability allow deployment at multiple sites within an urban air-shed and development of a ground-based monitoring network for studying small-scale atmospheric dynamics, spatial heterogeneities in trace gas distribution, local pollution conditions, photochemical processes and interdependencies of ozone and its major precursors. Results are shown for four mid- to high-latitude sites where different Pandora instruments were used. Comparisons with a well calibrated double-grating Brewer spectrometer over a period of more than a year in Greenbelt MD showed excellent agreement and a small bias of approximately 2 DU (or, 0.6%). This was constant with slant column ozone amount over the full range of observed solar zenith angles (15-80), indicating adequate Pandora stray light correction. A small (1-2%) seasonal difference was found, consistent with sensitivity studies showing that the Pandora spectral fitting TCO retrieval has a temperature dependence of 1% per 3K, with an underestimation in temperature (e.g., during summer) resulting in an underestimation of TCO. Pandora agreed well with Aura-OMI (Ozone Measuring Instrument) satellite data, with average residuals of <1% at the different sites when the OMI view was within 50 km from the Pandora location and OMI-measured cloud fraction was <0.2. The frequent and continuous measurements by Pandora revealed significant short-term (hourly) temporal changes in TCO, not possible to capture by sun-synchronous satellites, such as OMI, alone.

  19. Development of a High Precision Displacement Measurement System by Fusing a Low Cost RTK-GPS Sensor and a Force Feedback Accelerometer for Infrastructure Monitoring.

    Science.gov (United States)

    Koo, Gunhee; Kim, Kiyoung; Chung, Jun Yeon; Choi, Jaemook; Kwon, Nam-Yeol; Kang, Doo-Young; Sohn, Hoon

    2017-11-28

    A displacement measurement system fusing a low cost real-time kinematic global positioning system (RTK-GPS) receiver and a force feedback accelerometer is proposed for infrastructure monitoring. The proposed system is composed of a sensor module, a base module and a computation module. The sensor module consists of a RTK-GPS rover and a force feedback accelerometer, and is installed on a target structure like conventional RTK-GPS sensors. The base module is placed on a rigid ground away from the target structure similar to conventional RTK-GPS bases, and transmits observation messages to the sensor module. Then, the initial acceleration, velocity and displacement responses measured by the sensor module are transmitted to the computation module located at a central monitoring facility. Finally, high precision and high sampling rate displacement, velocity, and acceleration are estimated by fusing the acceleration from the accelerometer, the velocity from the GPS rover, and the displacement from RTK-GPS. Note that the proposed displacement measurement system can measure 3-axis acceleration, velocity as well as displacement in real time. In terms of displacement, the proposed measurement system can estimate dynamic and pseudo-static displacement with a root-mean-square error of 2 mm and a sampling rate of up to 100 Hz. The performance of the proposed system is validated under sinusoidal, random and steady-state vibrations. Field tests were performed on the Yeongjong Grand Bridge and Yi Sun-sin Bridge in Korea, and the Xihoumen Bridge in China to compare the performance of the proposed system with a commercial RTK-GPS sensor and other data fusion techniques.

  20. Development of a High Precision Displacement Measurement System by Fusing a Low Cost RTK-GPS Sensor and a Force Feedback Accelerometer for Infrastructure Monitoring

    Directory of Open Access Journals (Sweden)

    Gunhee Koo

    2017-11-01

    Full Text Available A displacement measurement system fusing a low cost real-time kinematic global positioning system (RTK-GPS receiver and a force feedback accelerometer is proposed for infrastructure monitoring. The proposed system is composed of a sensor module, a base module and a computation module. The sensor module consists of a RTK-GPS rover and a force feedback accelerometer, and is installed on a target structure like conventional RTK-GPS sensors. The base module is placed on a rigid ground away from the target structure similar to conventional RTK-GPS bases, and transmits observation messages to the sensor module. Then, the initial acceleration, velocity and displacement responses measured by the sensor module are transmitted to the computation module located at a central monitoring facility. Finally, high precision and high sampling rate displacement, velocity, and acceleration are estimated by fusing the acceleration from the accelerometer, the velocity from the GPS rover, and the displacement from RTK-GPS. Note that the proposed displacement measurement system can measure 3-axis acceleration, velocity as well as displacement in real time. In terms of displacement, the proposed measurement system can estimate dynamic and pseudo-static displacement with a root-mean-square error of 2 mm and a sampling rate of up to 100 Hz. The performance of the proposed system is validated under sinusoidal, random and steady-state vibrations. Field tests were performed on the Yeongjong Grand Bridge and Yi Sun-sin Bridge in Korea, and the Xihoumen Bridge in China to compare the performance of the proposed system with a commercial RTK-GPS sensor and other data fusion techniques.

  1. Geochemical and Sm–Nd isotopic study of titanite from granitoid ...

    Indian Academy of Sciences (India)

    in granitic magmas that have equilibrated with titanite during fractional crystallization or partial melting ... Titanite; Kolar; Ramagiri; Dharwar craton; rare earth elements; Sm–Nd isotope dating. J. Earth Syst. Sci. 120, No. 2, April 2011, pp. 237–251 c Indian Academy of Sciences ... be altered by variations in temperature and/or.

  2. High-precision dual-inlet IRMS measurements of the stable isotopes of CO2 and the N2O / CO2 ratio from polar ice core samples

    Directory of Open Access Journals (Sweden)

    T. K. Bauska

    2014-11-01

    Full Text Available An important constraint on mechanisms of past carbon cycle variability is provided by the stable isotopic composition of carbon in atmospheric carbon dioxide (δ13C-CO2 trapped in polar ice cores, but obtaining very precise measurements has proven to be a significant analytical challenge. Here we describe a new technique to determine the δ13C of CO2 at very high precision, as well as measuring the CO2 and N2O mixing ratios. In this method, ancient air is extracted from relatively large ice samples (~400 g with a dry-extraction "ice grater" device. The liberated air is cryogenically purified to a CO2 and N2O mixture and analyzed with a microvolume-equipped dual-inlet IRMS (Thermo MAT 253. The reproducibility of the method, based on replicate analysis of ice core samples, is 0.02‰ for δ13C-CO2 and 2 ppm and 4 ppb for the CO2 and N2O mixing ratios, respectively (1σ pooled standard deviation. Our experiments show that minimizing water vapor pressure in the extraction vessel by housing the grating apparatus in a ultralow-temperature freezer (−60 °C improves the precision and decreases the experimental blank of the method to −0.07 ± 0.04‰. We describe techniques for accurate calibration of small samples and the application of a mass-spectrometric method based on source fragmentation for reconstructing the N2O history of the atmosphere. The oxygen isotopic composition of CO2 is also investigated, confirming previous observations of oxygen exchange between gaseous CO2 and solid H2O within the ice archive. These data offer a possible constraint on oxygen isotopic fractionation during H2O and CO2 exchange below the H2O bulk melting temperature.

  3. WE-DE-201-07: Measurement of Real-Time Dose for Tandem and Ovoid Brachytherapy Procedures Using a High Precision Optical Fiber Radiation Detector

    Energy Technology Data Exchange (ETDEWEB)

    Belley, MD [Duke University, Durham, NC (United States); Current Address Rhode Island Hospital, Providence, RI (United States); Faught, A; Subashi, E; Chino, JP; Craciunescu, O [Duke University Medical Center, Durham, NC (United States); Moore, B; Langloss, B; Therien, MJ [Duke University, Durham, NC (United States); Yoshizumi, TT [Duke University, Durham, NC (United States); Duke University Medical Center, Durham, NC (United States)

    2016-06-15

    Purpose: Development of a novel on-line dosimetry tool is needed to move toward patient-specific quality assurance measurements for Ir-192 HDR brachytherapy to verify accurate dose delivery to the intended location. This work describes the development and use of a nano-crystalline yttrium oxide inorganic scintillator based optical-fiber detector capable of acquiring real-time high-precision dose measurements during tandem and ovoid (T&O) gynecological (GYN) applicator Ir-192 HDR brachytherapy procedures. Methods: An optical-fiber detector was calibrated by acquiring light output measurements in liquid water at 3, 5, 7, and 9cm radial source-detector-distances from an Ir-192 HDR source. A regression model was fit to the data to describe the relative light output per unit dose (TG-43 derived) as a function of source-detector-distance. Next, the optical-fiber detector was attached to a vaginal balloon fixed to a Varian Fletcher-Suit-Delclos-style applicator (to mimic clinical setup), and localized by acquiring high-resolution computed tomography (CT) images. To compare the physical point dose to the TPS calculated values (TG-43 and Acuros-BV), a phantom measurement was performed, by submerging the T&O applicator in a liquid water bath and delivering a treatment template representative of a clinical T&O procedure. The fiber detector collected scintillation signal as a function of time, and the calibration data was applied to calculate both real-time dose rate, and cumulative dose. Results: Fiber cumulative dose values were 100.0cGy, 94.3cGy, and 348.9cGy from the tandem, left ovoid, and right ovoid dwells, respectively (total of 443.2cGy). A plot of real time dose rate during the treatment was also acquired. The TPS values at the fiber location were 458.4cGy using TG-43, and 437.6cGy using Acuros-BV calculated as Dm,m (per TG-186). Conclusion: The fiber measured dose value agreement was 3% vs TG-43 and −1% vs Acuros-BV. This fiber detector opens up new possibilities

  4. Sr and Nd isotope systematics in fish teeth

    International Nuclear Information System (INIS)

    Staudigel, H.; Zindler, A.

    1985-01-01

    High concentrations of Sr and Nd in fish teeth apatite (up to 2000 and 3800 ppm, respectively) make them relatively impervious to diagenetic overprints and allow high-precision analysis of 87 Sr/ 86 Sr and 143 Nd/ 144 Nd of very small amounts of material. 87 Sr/ 86 Sr ratios of 14 Cenozoic samples ( 87 Sr/ 86 Sr stratigraphic dating. A compilation of published 143 Nd/ 144 Nd data from recent Mn-nodules and marine Fe/Mn deposits shows that the North-Central Pacific Ocean and the major portion of the Atlantic Ocean display distinctly different, narrow ranges in isotopic compositions. Between these two areas, the 143 Nd/ 144 Nd of Mn-nodules vary systematically towards intermediate compositions in the Southern Oceans, reflecting the communication between the Atlantic and Pacific Oceans through the eastward moving Antarctic Circumpolar Current. The 143 Nd/ 144 Nd of the 2-55 Ma old fish teeth analyzed are typically close to the range of 143 Nd/ 144 Nd in Recent Mn-nodules and seawater for the respective ocean and, thus, indicate no significant change through this time period. The 143 Nd/ 144 Nd of fish teeth from the North Pacific Ocean are highest during periods of high aeolian sedimentation. (orig.)

  5. AMOC Variability During the Last 400 ka from Nd Isotopes in a Southern Ocean Core

    Science.gov (United States)

    Lupien, R.; Pena, L.; Goldstein, S. L.

    2014-12-01

    Paleoceanographic studies have used Nd isotope ratios to characterize paleo-ocean deep-water mass distributions. The Southern Ocean has nearly homogeneous ɛNd that reflects the relative inputs from the north Atlantic and north Pacific, offering the possibility to quantify the AMOC strength through time. However, obtaining an ɛNd record from the Southern Ocean is a challenge because carbonates are poorly preserved there, hindering stratigraphic control and generally precluding use of this important substrate. Alternatively, studies of deep-sea corals and ferromanganese crusts provide snapshots or poor time resolution. Deep-sea core E33-22 (55°S, 120°W, 2743m) lies in the polar frontal zone of the Pacific sector, above the carbonate compensation depth, where foraminifera are preserved. It spans ~400,000 years (from the Holocene to MIS11) with a sedimentation rate of ~2.5 cm/kyr. We measured its ɛNd record with the purpose of determining the best estimate of the export of NADW out of the Atlantic system, which we suggest is our best measure of the vigor of the global thermohaline circulation system. The record shows expected ɛNd variability during orbital and sub-orbital time-scales, that is lower ɛNd during warm and higher ɛNd during cold climate intervals. Moreover, the record passes a critical test in that ɛNd-values are almost always between South Atlantic and Pacific values. The only exceptions are glacial periods when they coincide with South Atlantic values, indicating extension of Southern Ocean system into the South Atlantic. We conclude that these data represent a conservative record of AMOC variability through the late Pleistocene.

  6. High-precision measurements of uranium and thorium isotopic ratios by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS)

    Science.gov (United States)

    Wang, Lisheng; Ma, Zhibang; Duan, Wuhui

    2015-04-01

    Isotopic compositions of U-Th and 230Th dating have been widely used in earth sciences, such as chronology, geochemistry, oceanography and hydrology. In this study, five ages of different carbonate samples were measured using 230Th dating technique with U-Th high-precision isotopic measurements by multi-collector inductively coupled plasma mass spectrometry, in Uranium-series Chronology Laboratory, Institute of Geology and Geophysics, Chinese Academy of Sciences.In this study, the precision and accuracy of uranium isotopic composition were estimated by measuring the uranium ratios of NBS-CRM 112A, NBS-CRM U500 and HU-1. The mean measured ratios, 234U/238U = 52.86 (±0.04) × 10-6 and δ234U = -38.36 (±0.77) × 10-3 for NBS-CRM 112A, 234U/238U = 10.4184 (±0.0001) × 10-3, 236U/238U = 15.43 (±0.01) × 10-4 and 238U/235U = 1.00021 (±0.00002) for NBS-CRM U500, 234U/238U = 54.911 (±0.007) and δ234U = -1.04 (±0.13) × 10-3 for HU-1 (95% confidence levels). The U isotope data for standard reference materials are in excellent agreement with previous studies, further highlighting the reliability and analytical capabilities of our technique. We measured the thorium isotopic ratios of three different thorium standards by MC-ICPMS. The three standards (Th-1, Th-2 and Th-3) were mixed by HU-1 and NBS 232Th standard, with the 230Th/232Th ratios from 10-4 to 10-6. The mean measured atomic ratios, 230Th/232Th = 2.1227 (±0.0024) × 10-6, 2.7246 (±0.0026) × 10-5, and 2.8358 (±0.0007) × 10-4 for Th-1, Th-2 and Th-3 (95% confidence levels), respectively. Using this technique, the following standard samples were dated by MC-ICPMS. Sample RKM-4, collected from Babardos Kendal Hill terrace, was used during the first stage of the Uranium-Series Intercomparison Project (USIP-I). Samples 76001, RKM-5 and RKM-6 were studied during the second stage of the USIP program (USIP-II). Sample 76001 is a laminated flowstone, collected from Sumidero Terejapa, Chiapas, Mexico, and samples

  7. Pb, Sr and Nd isotope geological characteristics and its evolution of Jianchaling rock

    International Nuclear Information System (INIS)

    Pang Chunyong; Chen Minyang; Xu Wenxin

    2003-01-01

    It has been a long time debatable subject on the raw material source and its genesis of Jianchaling ultrabasic rock, because the original rock phases, the original mineral compositions, texture and structure, even part of the chemical components of the rocks had been changed completely after many periods and phases of metamorphism. According to the content of Pb, Rb, Sr, Nd elements and their Pb, Sr, Nd isotope compositions of the rocks, together with the isotope geological age of late magmatic activities, the authors analyze the evolution of Pb, Sr, Nd isotope compositions, The inferred initiate Nd isotope ratio of ultrabasic rocks is 0.510233, lower than that of meteorite unity at a corresponding period, its ε Nd(T)>O; The initiate Sr ratios inferred by the isotope geological age ranges from 0.702735 to 0.719028; Projecting the lead isotope compositions on the Pb tectonic evolution model, the result indicates that the raw material of Jianchaling ultrabasic rock coming from the deplete upper mantle. The ultrabasic magma which enrich of Mg, Ni and less S intruded the crust and formed the Jianchaling ultrabasic rock at late Proterozoic era (927 Ma±). The forming time of serpentinite is mostly equal to the granitoid intruding time, showing the intrusion o flate acidic magma caused a large scale alteration of the ultrabasic rocks and formed the meta-ultrabasic phase rock observed today. (authors)

  8. Further Sr and Nd isotopic results from peridotites of the Ronda Ultramafic Complex

    International Nuclear Information System (INIS)

    Reisberg, L.; Zindler, A.

    1989-01-01

    Clinopyroxenes derived from peridotites of the spinel and garnet facies of the Ronda Ultramafic Complex yield Sr and Nd isotopic ratios which extend the range of compositions found in the massif to values as depleted as 0.70205 for Sr and 0.51363 for Nd. Large-amplitude, short-wavelength isotopic variations are found to be uniquitous throughout the massif. In the garnet facies, some of these variations are shown to be produced by the tectonic disaggregation of mafic layers in an isotopically depleted peridotite matrix. Ages obtained from garnet-clinopyroxene Sm-Nd isochrons (about 22 m.y.) agree with previous determinations of the time of crustal emplacement. In the plagioclase facies, where the Sr and Nd isotopic compositions have been very strongly affected by recent cryptic metasomatism, detailed study of one sample reveals that intermineral Nd isotopic equilibrium exists between clinopyroxene, orthopyroxene, and plagioclase. This indicates that the metasomatism occurred at high temperatures, and thus probably within the mantle. A rough correlation between 143 Nd/ 144 Nd and 147 Sm/ 144 N, with an apparent 'age' of 1.3 b.y. and an initial ε Nd (0) value of +6.0, is observed among clinopyroxenes derived from river sediments from throughout the massif. This age is interpreted as the time that the massif left the convecting mantle and became incorporated into the sub-continental lithosphere. (orig.)

  9. High precision measurements of the differential W and Z boson cross-sections and top-quark pair to Z-boson cross-section ratios with the ATLAS detector

    CERN Document Server

    Zakharchuk, Nataliia; The ATLAS collaboration

    2017-01-01

    Measurements of the Drell-Yan production of W and Z/gamma* bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at center-of-mass energies of 7 TeV The measurements are performed for W+, W- and Z/gamma* bosons integrated and as a function of the boson or lepton rapidity and the Z/gamma* mass. This measurement allows for strong constraints on Parton Distribution functions, in particular the strange quark density. Z cross sections are also measured at a center-of-mass energies of 8 TeV and 13 TeV, and cross-section ratios to the top-quark pair production have been derived. This ratio measurement leads to a cancellation of several systematic effects and allows therefore for a high precision comparison to theory predictions.

  10. Initial-state-radiation production of D{sub s} Mesons and high precision measurements of D{sub s}1(2536) at Babar

    Energy Technology Data Exchange (ETDEWEB)

    Roney, Michael [Stanford Linear Accelerator Center - SLAC, National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025-7015 (United States); Izen, Joseph Michael [University of Texas at Dallas, Department of Physics, EC 36, 800 West Campbell Road, Richardson, Texas 75080-3021 (United States)

    2010-07-01

    A search for charmonium and other new states is performed in a study of exclusive initial-state-radiation production of D{sub s}{sup +}D{sub s}{sup -}, D{sub s}{sup *+}D{sub s}{sup -}, and D{sub s}{sup *+}D{sub s}{sup *-} events from electron-positron annihilations at a center-of-mass energy of 10.58 GeV. The data sample corresponds to an integrated luminosity of 525 fb{sup -1} recorded by the BaBar experiment at the PEP-II storage ring. We also study the decay width and the mass of the D{sub s}1(2536) meson with high precision via the decay channel D{sub s}1(2536){yields}D{sup +*} K{sup 0}{sub s} using 384 fb{sup -1} of data recorded by the BABAR experiment. (author)

  11. Recent high precision surveys at PEP

    International Nuclear Information System (INIS)

    Sah, R.C.

    1980-12-01

    The task of surveying and aligning the components of PEP has provided an opportunity to develop new instruments and techniques for the purpose of high precision surveys. The new instruments are quick and easy to use, and they automatically encode survey data and read them into the memory of an on-line computer. When measurements of several beam elements have been taken, the on-line computer analyzes the measured data, compares them with desired parameters, and calculates the required adjustments to beam element support stands

  12. High precision redundant robotic manipulator

    International Nuclear Information System (INIS)

    Young, K.K.D.

    1998-01-01

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space is disclosed. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degrees of freedom. Each of the embodiments utilize a first selective compliant assembly robot arm (SCARA) configuration to provide high stiffness in the vertical plane, a second SCARA configuration to provide high stiffness in the horizontal plane. The seven degree of freedom embodiment also utilizes kinematic redundancy to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector or link of the manipulator. These additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw and roll. The seven degrees of freedom embodiment uses one revolute point per degree of freedom. For each of the revolute joints, a harmonic gear coupled to an electric motor is introduced, and together with properly designed based servo controllers provide an end point repeatability of less than 10 microns. 3 figs

  13. Automatic titrator for high precision plutonium assay

    International Nuclear Information System (INIS)

    Jackson, D.D.; Hollen, R.M.

    1986-01-01

    Highly precise assay of plutonium metal is required for accountability measurements. We have developed an automatic titrator for this determination which eliminates analyst bias and requires much less analyst time. The analyst is only required to enter sample data and start the titration. The automated instrument titrates the sample, locates the end point, and outputs the results as a paper tape printout. Precision of the titration is less than 0.03% relative standard deviation for a single determination at the 250-mg plutonium level. The titration time is less than 5 min

  14. Geochemistry of trace elements and Sr- Nd isotopes of foraminifera shell from the Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Trace elemental associations and Sr - Nd isotopic compositions are of important to recognition of biogenic material from mixed marine sediments. The foraminifera shell from the Okinawa Trough strongly enrichesSr, P, Mn andBa, enriches Li, U, Th, Sc, Co, Cu, Pb, Zn, Cr, Rb, Y, Sb and light rare earth elements, slightly enriches V, Ga, Zr, Nb, Cd and middle rare earth elements,is short of Mo, In, Sn, Cs, Hf, Ta, W, Ti, Bi and heavy rare earth elements. The mechanism of elemental enrichment in forminifera is the concentrations of trace elements in sea water and selective absorption of trace elements during foraminifera living, as well as the geochemical affinity between major elements and trace elements. The REE (rare earth elements) partition pattern of foraminifera shell of the Okinawa Trough shows enrichment of middle rare earth elements with slightly negative Ce anomaly,which are different from those of foraminifera of the Pacific Ocean. The Sr, Nd isotopic ratios of the Okinawa Trough foraminifera are 0.709 769 and 0.512 162, respectively, which are different not only from those of oceanic water, but also from those of river water of China's Mainland, the former is slightly higher than those of oceanic water, but much lower than those of river water; the latter is slightly lower than those of oceanic water, but higher than those of river water, demonstrating that the Okinawa Trough sea water has been influenced by river water of China's Mainland.

  15. Trace-element and Sr-Nd isotopic evidence for the origin of the Sardinian fluorite mineralization (Italy)

    International Nuclear Information System (INIS)

    Castorina, F.; Masi, U.; Padalino, G.; Palomba, M.

    2008-01-01

    The fluorite-bearing hydrothermal mineralization in Sardinia mainly occurs within Paleozoic volcanic and metasedimentary rocks. Only 3 occurrences are located in volcanic and siliciclastic Cenozoic rocks. Most Sardinian fluorites exhibit relatively high rare earth and Y (REY) contents, strong positive Y anomalies, slightly negative Ce and generally positive Eu anomalies. These features indicate that the REY were mobilized mainly from non-carbonate rocks. Neither Sr nor Nd isotopes can be used to date radiometrically the Sardinian fluorites. However, the measured Sr-isotope ratios of the fluorites hosted by Paleozoic rocks fit mixing lines in the 1000/Sr versus 87 Sr/ 86 Sr plot once recalculated at 280 Ma, suggesting that the age inferred for the correction probably represents that of the formation of the fluorite mineralization. Mixing likely occurred between diluted surficial waters and brines circulating mainly through the Lower Paleozoic metasedimentary basement. The Cenozoic fluorites exhibit chemical and isotopic features similar to those of the Paleozoic fluorites, except the Nuraghe Onigu fluorite displaying a possible contribution of Sr from Cenozoic magmatic rocks. The initial ε Nd values of the Paleozoic fluorites fit the age proposed for the formation of the deposits. Moreover, the values suggest that radiogenic Nd was provided to the fluids from the Ordovician siliciclastic basement, except for 3 deposits where the potential source rocks of Nd were mainly Ordovician acidic magmatic rocks. The initial ε Nd values of the Cenozoic fluorites suggest a provenance of Nd essentially from the leaching of Variscan granitoids

  16. Development of a nano-tesla magnetic field shielded chamber and highly precise AC-susceptibility measurement coil at μK temperatures

    Science.gov (United States)

    Kumar, Anil; Prakash, Om; Ramakrishanan, S.

    2014-04-01

    A special sample measurement chamber has been developed to perform experiments at ultralow temperatures and ultralow magnetic field. A high permeability material known as cryoperm 10 and Pb is used to shield the measurement space consisting of the signal detecting set-up and the sample. The detecting setup consists of a very sensitive susceptibility coil wound on OFHC Cu bobbin.

  17. Study on Sr-Nd isotopes of mesozoic-cenozoic granites in Qinghai-Tibetan plateau

    International Nuclear Information System (INIS)

    Qiu Ruizhao; Deng Jinfu; Zhou Su; Xiao Qinghui; Cai Zhiyong

    2003-01-01

    Mesozoic-Cenozoic magmatic activities were intensive in Qinghai-Tibetan plateau. Nd-Sr isotopic compositions of representative granitic plutons in western Qinghai-Tibetan plateau are reported in this paper. Combining with past isotopic data, which has reported in eastern Qinghai-Tibetan plateau, Sr-Nd isotopic compositions and material source and genesis of Mesozoic and Cenozoic granites in Qinghai-Tibetan plateau have been studied. The research result indicates there are three types of granite existing in Qinghai-Tibetan plateau, the granites of Late stage of Yanshan Period which distributing on north and south boundary of Gandes block (namely in north and south granitic belts of Dangdes) and cause of oceanic crust subduction, have ( 87 Sr/ 86 Sr)i of 0.7041-0.7064, ε (Nd) t of +2.5 - +5.7 and TDM age of 312-562 Ma, positive ε Nd, low ( 87 Sr/ 86 Sr)i ratio and young Nd model ages suggest relatively high contents of mantle-derived components in their sources, and this type granite might melt from subduction oceanic crust. The granites occurred intra-Gangdes block which were caused by collision of continent and post-collision, have ( 87 Sr/ 86 Sr)i of 0.706-0.719, ε (Nd) t of -5.3 - -8.3 and TDM age of 1323-1496 Ma, negative ε Nd, relative high ( 87 Sr/ 86 Sr)i ratio with an mid-Proterozoic Nd model ages, suggest granite has the mixing genesis of mantle-derived components and old crustal components in their sources. With relatively small variation range in ε (Nd) t and TDM age, it might imply granitic isotopic source in Gandes block to keep relative homogenization in long period. The granites in Himalayan block which there is not oceanic material to join in melting and to cause of intra-continental subduction, has most ( 87 Sr/ 86 Sr)i ratio more than 0.720, ε (Nd) t of -10.3 - -16.3 and TDM age of 1792-2206 Ma, high ( 87 Sr/ 86 Sr)i ratio, low negative ε (Nd)t with old Nd isotopic model ages and consistent with the Sr, Nd isotopic compositions of basement

  18. A Sm-Nd isotopic study of atmospheric dusts and particulates from major river systems

    International Nuclear Information System (INIS)

    Goldstein, S.L.; Cambridge Univ.; O'Nions, R.K.; Hamilton, P.J.

    1984-01-01

    143 Nd/ 144 Nd ratios, and Sm and Nd abundances, are reported for particulates from major and minor rivers of the Earth, continental sediments, and aeolian dusts collected over the Atlantic, Pacific, and Indian Oceans. Overall, Sm/Nd ratios and Nd isotopic compositions in contemporary continental erosion products vary within the small ranges of 147 Sm/ 144 Nd=0.115 +- 0.01 and 143 Nd/ 144 Nd=0.51204 +- 0.0002 (epsilonsub(Nd)=-11.4 +- 4). The average period of residence in the continental crust is estimated to be 1.70 +- 0.35 Ga. These results combined with data from the literature have implications for the age, history, and composition of the sedimentary mass and the continental crust: (1) The average 'crustal residence age' of the whole sedimentary mass is about 1.9 Ga. (2) The range of Nd isotope compositions in the continent derived particulate input to the oceans is the same as Atlantic sediments and seawater, but lower than those of the Pacific, demonstrating the importance of Pacific volcanism to Pacific Nd chemistry. (3) The average ratio of Sm/Nd is about 0.19 in the upper continental crust, and has remained so since the early Archean. This precludes the likelihood of major mafic to felsic or felsic to mafic trends in the overall composition of the upper continental crust through Earth history. (4) Sediments appear to be formed primarily by erosion of continental crust having similar Sm/Nd ratios, rather than by mixing of mafic and felsic compositions. (5) The average ratio of 143 Nd/ 144 Nd approx.= 0.5117 (epsilonsub(Nd) approx.= -17) in the upper continental crust, assuming its mean age is about 2 Ga. (6) The uniformity of the Sm-Nd isotopic systematics in river and aeolian particulates primarily reflects efficient recycling of old sediment by sedimentary processes on a short time scale compared to the amount of time the material has resided in the crust. (orig.)

  19. A high-precision continuous measurement system for the atmospheric O_2/N_2 ratio at Ny-Alesund, Svalbard and preliminary observational results

    Directory of Open Access Journals (Sweden)

    Daisuke Goto

    2013-03-01

    Full Text Available With the aim of carrying out detailed monitoring of temporal variations in the atmospheric O_2/N_2 ratio at Ny-Alesund, Svalbard, we have developed a new highprecision continuous measurement system, with a precision of better than ±4.0 per meg, using a fuel-cell O_2 analyzer. Considering the remoteness of the observation site, special attention was paid to the measurement system, in that: (1 the system can be controlled remotely from Japan using the Internet; (2 all of the data output from the system can be monitored and collected in Japan via the Internet; (3 a specially designed water trap based on a Stirling cooler is employed to automate the removal of water vapor from the sample air; (4 the CO_2 concentration can also be measured; and (5 it is possible to operate the system for one year without having to manually replace the high-pressure cylinders of standard gas and reference air. Systematic observation of the atmospheric O_2/N_2 ratio using the newly developed measurement system began at the site on November 8, 2012. By analyzing the observational results obtained over the first month, the effectiveness of the measurement system was verified, and the causes of cha acteristic temporal variations in the observed atmospheric O_2/N_2 ratio were examined.

  20. High-precision half-life measurements of the T=1/2 mirror beta decays F-17 and Cl-33

    OpenAIRE

    Grinyer, J; Grinyer, G. F; Babo, Mathieu; Bouzomita, H; Chauveau, P; Delahaye, P; Dubois, M; Frigot, R; Jardin, P; Leboucher, C; Maunoury, L; Seiffert, C; Thomas, J. C; Traykov, E

    2015-01-01

    Background: Measurements of the ft values for T=1/2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the ft values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T=1/2β+ emitters, 17F and 33Cl, in order to eliminate the half-life as th...

  1. High-precision half-life measurements of the T=1/2 mirror β decays F17 and Cl33

    OpenAIRE

    Grinyer, J; Grinyer, G F; Babo, M; Bouzomita, H; Chauveau, P; Delahaye, P; Dubois, M; Frigot, R; Jardin, P; Leboucher, C; Maunoury, L; Seiffert, C; Thomas, J C; Traykov, E

    2015-01-01

    Background: Measurements of the ft values for T=1/2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the ft values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T=1/2β+ emitters, F17 and Cl33, in order to eliminate the half-life as the le...

  2. High-precision Measurement of the 238U(n,γ) Cross Section with the Total Absorption Calorimeter (TAC) at n_TOF, CERN

    CERN Document Server

    Wright, T; Billowes, J; Ware, T; Cano-Ott, D; Mendoza, E; Massimi, C; Mingrone, F; Gunsing, F; Berthoumieux, E; Lampoudis, C; Altstadt, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Bécares, V; Bečvář, F; Belloni, F; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calviño, F; Carrapiço, C; Cerutti, F; Chiaveri, E; Chin, M; Colonna, N; Cortés, G; Cortés-Giraldo, M A; Diakaki, M; Domingo-Pardo, C; Duran, I; Dressler, R; Dzysiuk, N; Eleftheriadis, C; Ferrari, A; Fraval, K; Ganesan, S; García, A R; Gómez-Hornillos, M B; Gonçalves, I F; González-Romero, E; Griesmayer, E; Giubrone, G; Gurusamy, P; Jenkins, D G; Jericha, E; Kadi, Y; Käppeler, F; Karadimos, D; Kivel, N; Koehler, P; Kokkoris, M; Korschinek, G; Krtička, M; Kroll, J; Langer, C; Lederer, C; Leeb, H; Leong, L S; Losito, R; Manousos, A; Marganiec, J; Martínez, T; Mastinu, P F; Mastromarco, M; Meaze, M; Mengoni, A; Milazzo, P M; Mirea, M; Mondelaers, W; Paradela, C; Pavlik, A; Perkowski, J; Pignatari, M; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Reifarth, R; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Schillebeeckx, P; Schmidt, S; Schumann, D; Tagliente, G; Tain, J L; Tarrío, D; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Weigand, M; Weiß, C; Žugec, P

    2014-01-01

    The neutron capture cross section of U-238 is fundamental to the design and operation of current reactors and future fast nuclear reactors, and thus must be measured to a high level of accuracy. An experiment has been performed at the CERN n TOF facility using a 4 pi Total Absorption Calorimeter (TAC) to measure the capture cross section in the resolved resonance region between 1 eV and 25 keV. A preliminary analysis of the TAC data is presented with particular emphasis to the experimental background in this energy region of interest.

  3. A High Precision Approach to Calibrate a Structured Light Vision Sensor in a Robot-Based Three-Dimensional Measurement System

    Directory of Open Access Journals (Sweden)

    Defeng Wu

    2016-08-01

    Full Text Available A robot-based three-dimensional (3D measurement system is presented. In the presented system, a structured light vision sensor is mounted on the arm of an industrial robot. Measurement accuracy is one of the most important aspects of any 3D measurement system. To improve the measuring accuracy of the structured light vision sensor, a novel sensor calibration approach is proposed to improve the calibration accuracy. The approach is based on a number of fixed concentric circles manufactured in a calibration target. The concentric circle is employed to determine the real projected centres of the circles. Then, a calibration point generation procedure is used with the help of the calibrated robot. When enough calibration points are ready, the radial alignment constraint (RAC method is adopted to calibrate the camera model. A multilayer perceptron neural network (MLPNN is then employed to identify the calibration residuals after the application of the RAC method. Therefore, the hybrid pinhole model and the MLPNN are used to represent the real camera model. Using a standard ball to validate the effectiveness of the presented technique, the experimental results demonstrate that the proposed novel calibration approach can achieve a highly accurate model of the structured light vision sensor.

  4. High-precision measurement of the 238U(n,γ) cross-section at the n-TOF facility, CERN

    International Nuclear Information System (INIS)

    Wright, Tobias James; Billowes, Jon; Mingrone, Federica; Massimi, Cristian; Berthoumieux, Eric; Gunsing, Frank; Cano-Ott, Daniel; Mendoza, Emilio; Guerrero, Carlos; Schillebeeckx, P.

    2014-01-01

    A new experiment to measure the 238 U(n,γ) cross-section has been carried out at the CERN n-TOF facility within the ANDES project. Two complementary detection systems have been used: two low neutron sensitivity C6D6 detectors and the Total Absorption Calorimeter (TAC) comprising 40 BaF 2 scintillators. High quality data has been obtained up to 10 keV with the TAC and up to a higher neutron energy unresolved region with the C 6 D 6 . All the steps in the measurements and the subsequent data analysis are dealt with in depth, aiming for overall 2-3% accuracy per detection system. (authors)

  5. High-precision measurement of the electron spin g factor of trapped atomic nitrogen in the endohedral fullerene N@C60

    Science.gov (United States)

    Wittmann, J. J.; Can, T. V.; Eckardt, M.; Harneit, W.; Griffin, R. G.; Corzilius, B.

    2018-05-01

    The electronic g factor carries highly useful information about the electronic structure of a paramagnetic species, such as spin-orbit coupling and dia- or paramagnetic (de-)shielding due to local fields of surrounding electron pairs. However, in many cases, a near "spin-only" case is observed, in particular for light elements, necessitating accurate and precise measurement of the g factors. Such measurement is typically impeded by a "chicken and egg situation": internal or external reference standards are used for relative comparison of electron paramagnetic resonance (EPR) Larmor frequencies. However, the g factor of the standard itself usually is subject to a significant uncertainty which directly limits the precision and/or accuracy of the sought after sample g factor. Here, we apply an EPR reference-free approach for determining the g factor of atomic nitrogen trapped within the endohedral fullerene C60:N@C60 in its polycrystalline state by measuring the 1H NMR resonance frequency of dispersing toluene at room temperature. We found a value of g = 2.00204 (4) with a finally reached relative precision of ∼20 ppm. This accurate measurement allows us to directly compare the electronic properties of N@C60 to those found in atomic nitrogen in the gas phase or trapped in other solid matrices at liquid helium temperature. We conclude that spin-orbit coupling in N@C60 at room temperature is very similar in magnitude and of same sign as found in other inert solid matrices and that interactions between the quartet spin system and the C60 molecular orbitals are thus negligible.

  6. STELLAR DIAMETERS AND TEMPERATURES. III. MAIN-SEQUENCE A, F, G, AND K STARS: ADDITIONAL HIGH-PRECISION MEASUREMENTS AND EMPIRICAL RELATIONS

    International Nuclear Information System (INIS)

    Boyajian, Tabetha S.; Jones, Jeremy; White, Russel; McAlister, Harold A.; Gies, Douglas; Von Braun, Kaspar; Van Belle, Gerard; Farrington, Chris; Schaefer, Gail; Ten Brummelaar, Theo A.; Sturmann, Laszlo; Sturmann, Judit; Turner, Nils H.; Goldfinger, P. J.; Vargas, Norm; Ridgway, Stephen

    2013-01-01

    Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity classes V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data is used to derive color-temperature relations to an assortment of color indices in the Johnson (BVR J I J JHK), Cousins (R C I C ), Kron (R K I K ), Sloan (griz), and WISE (W 3 W 4 ) photometric systems. These relations have an average standard deviation of ∼3% and are valid for stars with spectral types A0-M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (T eff > 6750 K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only ∼2.5%. We find effective temperatures in agreement within a couple of percent for the interferometrically characterized sample of main-sequence stars compared to those derived via the infrared flux method and spectroscopic analysis.

  7. High precision neutron polarization for PERC

    International Nuclear Information System (INIS)

    Klauser, C.

    2013-01-01

    The decay of the free neutron into a proton, an electron and an anti-electron neutrino offers a simple system to study the semi-leptonic weak decay. High precision measurements of angular correlation coefficients of this decay provide the opportunity to test the standard model on the low energy frontier. The Proton Electron Radiation Channel PERC is part of a new generation of expriments pushing the accuracy of such an angular correlation coefficient measurement towards 10 -4 . Past experiments have been limited to an accuracy of 10 -3 with uncertainties on the neutron polarization as one of the leading systematic errors. This thesis focuses on the development of a stable, highly precise neutron polarization for a large, divergent cold neutron beam. A diagnostic tool that provides polarization higher than 99.99 % and analyzes with an accuracy of 10 -4 , the Opaque Test Bench, is presented and validated. It consists of two highly opaque polarized helium cells. The Opaque Test Bench reveals depolarizing effects in polarizing supermirrors commonly used for polarization in neutron decay experiments. These effects are investigated in detail. They are due to imperfect lateral magnetization in supermirror layers and can be minimized by significantly increased magnetizing fields and low incidence angle and supermirror factor m. A subsequent test in the crossed (X-SM) geometry demonstrated polarizations up to 99.97% from supermirrors only, improving neutron polarization with supermirrors by an order of magnitude. The thesis also discusses other neutron optical components of the PERC beamline: Monte-Carlo simulations of the beamline under consideration of the primary guide are carried out. In addition, calculation shows that PERC would statistically profit from an installation at the European Spallation source. Furthermore, beamline components were tested. A radio-frequency spin flipper was confirmed to work with an efficiency higher than 0.9999. (author) [de

  8. Research on High-Precision, Low Cost Piezoresistive MEMS-Array Pressure Transmitters Based on Genetic Wavelet Neural Networks for Meteorological Measurements

    Directory of Open Access Journals (Sweden)

    Jiahong Zhang

    2015-05-01

    Full Text Available This paper provides a novel and effective compensation method by improving the hardware design and software algorithm to achieve optimization of piezoresistive pressure sensors and corresponding measurement systems in order to measure pressure more accurately and stably, as well as to meet the application requirements of the meteorological industry. Specifically, GE NovaSensor MEMS piezoresistive pressure sensors within a thousandth of accuracy are selected to constitute an array. In the versatile compensation method, the hardware utilizes the array of MEMS pressure sensors to reduce random error caused by sensor creep, and the software adopts the data fusion technique based on the wavelet neural network (WNN which is improved by genetic algorithm (GA to analyze the data of sensors for the sake of obtaining accurate and complete information over the wide temperature and pressure ranges. The GA-WNN model is implemented in hardware by using the 32-bit STMicroelectronics (STM32 microcontroller combined with an embedded real-time operating system µC/OS-II to make the output of the array of MEMS sensors be a direct digital readout. The results of calibration and test experiments clearly show that the GA-WNN technique can be effectively applied to minimize the sensor errors due to the temperature drift, the hysteresis effect and the long-term drift because of aging and environmental changes. The maximum error of the low cost piezoresistive MEMS-array pressure transmitter proposed by us is within 0.04% of its full-scale value, and it can satisfy the meteorological pressure measurement.

  9. STELLAR DIAMETERS AND TEMPERATURES. III. MAIN-SEQUENCE A, F, G, AND K STARS: ADDITIONAL HIGH-PRECISION MEASUREMENTS AND EMPIRICAL RELATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Boyajian, Tabetha S.; Jones, Jeremy; White, Russel; McAlister, Harold A.; Gies, Douglas [Center for High Angular Resolution Astronomy and Department of Physics and Astronomy, Georgia State University, P.O. Box 4106, Atlanta, GA 30302-4106 (United States); Von Braun, Kaspar [NASA Exoplanet Science Institute, California Institute of Technology, MC 100-22, Pasadena, CA 91125 (United States); Van Belle, Gerard [Lowell Observatory, Flagstaff, AZ 86001 (United States); Farrington, Chris; Schaefer, Gail; Ten Brummelaar, Theo A.; Sturmann, Laszlo; Sturmann, Judit; Turner, Nils H.; Goldfinger, P. J.; Vargas, Norm [CHARA Array, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States); Ridgway, Stephen [National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726-6732 (United States)

    2013-07-01

    Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity classes V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data is used to derive color-temperature relations to an assortment of color indices in the Johnson (BVR{sub J} I{sub J} JHK), Cousins (R{sub C} I{sub C}), Kron (R{sub K} I{sub K}), Sloan (griz), and WISE (W{sub 3} W{sub 4}) photometric systems. These relations have an average standard deviation of {approx}3% and are valid for stars with spectral types A0-M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (T{sub eff} > 6750 K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only {approx}2.5%. We find effective temperatures in agreement within a couple of percent for the interferometrically characterized sample of main-sequence stars compared to those derived via the infrared flux method and spectroscopic analysis.

  10. High precision tracking and the measurement of B(Z → b bar b)/B(Z → hadrons) with the Mark II at the SLC

    International Nuclear Information System (INIS)

    Schumm, B.A.

    1991-03-01

    During the 1990 run of the Mark II at the SLC, the precision tracking system achieved a preliminary impact parameter resolution of 35.8 ± 1.3 μm for high momentum tracks, which is the quadrature sum of 25 ± 5 μm of intrinsic resolution smearing dominated by misalignments and other geometrical effects. A method is proposed by which this system can be used to measure B(Z → b rvec b/B(Z → hadrons)) with minimal systematic error. 6 refs., 3 figs

  11. High precision measurement of the e+e- → e+e- angular distribution at √s = 29 GeV

    International Nuclear Information System (INIS)

    Fernandez, E.; Ford, W.T.; Qi, N.

    1984-07-01

    We present the differential angular cross section for Bhabha scattering as measured by the MAC detector at PEP, based on a 127 pb -1 sample at √s = 29 GeV. A fit of the cross section to the prediction of the electroweak standard model yields g/sub a/ 2 = 0.33 +- 0.24 and g/sub v/ 2 = 0.09 +- 0.14 at m/sub Z/ = 90 GeV. The pure QED solution g/sub a/ = g/sub v/ = 0 is excluded at the 2 standard deviation level. 8 references

  12. High-precision measurement of mercury isotope ratios in sediments using cold-vapor generation multi-collector inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Foucher, Delphine; Hintelmann, Holger

    2006-01-01

    An on-line Hg reduction technique using stannous chloride as the reductant was applied for accurate and precise mercury isotope ratio determinations by multi-collector (MC)-ICP/MS. Special attention has been paid to ensure optimal conditions (such as acquisition time and mercury concentration) allowing precision measurements good enough to be able to significantly detect the anticipated small differences in Hg isotope ratios in nature. Typically, internal precision was better than 0.002% (1 RSE) on all Hg ratios investigated as long as approximately 20 ng of Hg was measured with a 10-min acquisition time. Introducing higher amounts of mercury (50 ng Hg) improved the internal precision to 205 Tl/ 203 Tl correction coupled to a standard-sample bracketing approach. The large number of data acquired allowed us to validate the consistency of our measurements over a one-year period. On average, the short-term uncertainty determined by repeated runs of NIST SRM 1641d Hg standard during a single day was 202 Hg/ 198 Hg, 202 Hg/ 199 Hg, 202 Hg/ 200 Hg, and 202 Hg/ 201 Hg). The precision fell to 202 Hg/ 198 Hg expressed as δ values (per mil deviations relative to NIST SRM 1641d Hg standard solution) displayed differences from +0.74 to -4.00 permille. The magnitude of the Hg fractionation per amu was constant within one type of sample and did not exceed 1.00 permille. Considering all results (the reproducibility of Hg standard solutions, reference sediment samples, and the examination of natural samples), the analytical error of our δ values for the overall method was within ±0.28 permille (1 SD), which was an order of magnitude lower than the extent of fractionation (4.74 permille) observed in sediments. This study confirmed that analytical techniques have reached a level of long-term precision and accuracy that is sufficiently sensitive to detect even small differences in Hg isotope ratios that occur within one type of samples (e.g., between different sediments) and so

  13. The effects of repeated testing, simulated malingering, and traumatic brain injury on high-precision measures of simple visual reaction time

    Directory of Open Access Journals (Sweden)

    David L Woods

    2015-11-01

    Full Text Available Simple reaction time (SRT, the latency to respond to a stimulus, has been widely used as a basic measure of processing speed. In the current experiments, we examined clinically-relevant properties of a new SRT test that presents visual stimuli to the left or right hemifield at varying stimulus onset asynchronies. Experiment 1 examined test-retest reliability in participants who underwent three test sessions at weekly intervals. In the first test, log-transformed (log-SRT z-scores, corrected for the influence of age and computer-use, were well predicted by regression functions derived from a normative population of 189 control participants. Test-retest reliability of log-SRT z-scores was measured with an intraclass correlation coefficient (ICC = 0.83 and equaled or exceeded those of other SRT tests and other widely used tests of processing speed that are administered manually. No significant learning effects were observed across test sessions. Experiment 2 investigated the same participants when instructed to malinger during a fourth testing session: 94% showed abnormal log-SRT z-scores, with 83% producing log-SRT z-scores exceeding a cutoff of 3.0, a degree of abnormality never seen in full-effort conditions. Thus, a log-SRT z-score cutoff of 3.0 had a sensitivity (83% and specificity (100% that equaled or exceeded that of existing symptom validity tests. We argue that even expert malingerers, fully informed of the malingering-detection metric, would be unable to successfully feign impairments on the SRT test because of the precise control of SRT latencies that would be required. Experiment 3 investigated 26 patients with traumatic brain injury (TBI tested more than one year post-injury. The 22 patients with mild TBI showed insignificantly faster SRTs than controls, but a small group of four patients with severe TBI showed slowed SRTs. Simple visual reaction time is a reliable measure of processing speed that is sensitive to the effects of

  14. On the calibration of continuous, high-precision delta18O and delta2H measurements using an off-axis integrated cavity output spectrometer.

    Science.gov (United States)

    Wang, Lixin; Caylor, Kelly K; Dragoni, Danilo

    2009-02-01

    The (18)O and (2)H of water vapor serve as powerful tracers of hydrological processes. The typical method for determining water vapor delta(18)O and delta(2)H involves cryogenic trapping and isotope ratio mass spectrometry. Even with recent technical advances, these methods cannot resolve vapor composition at high temporal resolutions. In recent years, a few groups have developed continuous laser absorption spectroscopy (LAS) approaches for measuring delta(18)O and delta(2)H which achieve accuracy levels similar to those of lab-based mass spectrometry methods. Unfortunately, most LAS systems need cryogenic cooling and constant calibration to a reference gas, and have substantial power requirements, making them unsuitable for long-term field deployment at remote field sites. A new method called Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) has been developed which requires extremely low-energy consumption and neither reference gas nor cryogenic cooling. In this report, we develop a relatively simple pumping system coupled to a dew point generator to calibrate an ICOS-based instrument (Los Gatos Research Water Vapor Isotope Analyzer (WVIA) DLT-100) under various pressures using liquid water with known isotopic signatures. Results show that the WVIA can be successfully calibrated using this customized system for different pressure settings, which ensure that this instrument can be combined with other gas-sampling systems. The precisions of this instrument and the associated calibration method can reach approximately 0.08 per thousand for delta(18)O and approximately 0.4 per thousand for delta(2)H. Compared with conventional mass spectrometry and other LAS-based methods, the OA-ICOS technique provides a promising alternative tool for continuous water vapor isotopic measurements in field deployments. Copyright 2009 John Wiley & Sons, Ltd.

  15. High precision Standard Model Physics

    International Nuclear Information System (INIS)

    Magnin, J.

    2009-01-01

    The main goal of the LHCb experiment, one of the four large experiments of the Large Hadron Collider, is to try to give answers to the question of why Nature prefers matter over antimatter? This will be done by studying the decay of b quarks and their antimatter partners, b-bar, which will be produced by billions in 14 TeV p-p collisions by the LHC. In addition, as 'beauty' particles mainly decay in charm particles, an interesting program of charm physics will be carried on, allowing to measure quantities as for instance the D 0 -D-bar 0 mixing, with incredible precision.

  16. Validation of an analytical method for simultaneous high-precision measurements of greenhouse gas emissions from wastewater treatment plants using a gas chromatography-barrier discharge detector system.

    Science.gov (United States)

    Pascale, Raffaella; Caivano, Marianna; Buchicchio, Alessandro; Mancini, Ignazio M; Bianco, Giuliana; Caniani, Donatella

    2017-01-13

    Wastewater treatment plants (WWTPs) emit CO 2 and N 2 O, which may lead to climate change and global warming. Over the last few years, awareness of greenhouse gas (GHG) emissions from WWTPs has increased. Moreover, the development of valid, reliable, and high-throughput analytical methods for simultaneous gas analysis is an essential requirement for environmental applications. In the present study, an analytical method based on a gas chromatograph (GC) equipped with a barrier ionization discharge (BID) detector was developed for the first time. This new method simultaneously analyses CO 2 and N 2 O and has a precision, measured in terms of relative standard of variation RSD%, equal to or less than 6.6% and 5.1%, respectively. The method's detection limits are 5.3ppm v for CO 2 and 62.0ppb v for N 2 O. The method's selectivity, linearity, accuracy, repeatability, intermediate precision, limit of detection and limit of quantification were good at trace concentration levels. After validation, the method was applied to a real case of N 2 O and CO 2 emissions from a WWTP, confirming its suitability as a standard procedure for simultaneous GHG analysis in environmental samples containing CO 2 levels less than 12,000mg/L. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. High Precision Seawater Sr/Ca Measurements in the Florida Keys by Inductively Coupled Plasma Atomic Emission Spectrometry: Analytical Method and Implications for Coral Paleothermometry

    Science.gov (United States)

    Khare, A.; Kilbourne, K. H.; Schijf, J.

    2017-12-01

    Standard methods of reconstructing past sea surface temperatures (SSTs) with coral skeletal Sr/Ca ratios assume the seawater Sr/Ca ratio is constant. However, there is little data to support this assumption, in part because analytical techniques capable of determining seawater Sr/Ca with sufficient accuracy and precision are expensive and time consuming. We demonstrate a method to measure seawater Sr/Ca using inductively coupled plasma atomic emission spectrometry where we employ an intensity ratio calibration routine that reduces the self- matrix effects of calcium and cancels out the matrix effects that are common to both calcium and strontium. A seawater standard solution cross-calibrated with multiple instruments is used to correct for long-term instrument drift and any remnant matrix effects. The resulting method produces accurate seawater Sr/Ca determinations rapidly, inexpensively, and with a precision better than 0.2%. This method will make it easier for coral paleoclimatologists to quantify potentially problematic fluctuations in seawater Sr/Ca at their study locations. We apply our method to test for variability in surface seawater Sr/Ca along the Florida Keys Reef Tract. We are collecting winter and summer samples for two years in a grid with eleven nearshore to offshore transects across the reef, as well as continuous samples collected by osmotic pumps at four locations adjacent to our grid. Our initial analysis of the grid samples indicates a trend of decreasing Sr/Ca values offshore potentially due to a decreasing groundwater influence. The values differ by as much as 0.05 mmol/mol which could lead to an error of 1°C in mean SST reconstructions. Future work involves continued sampling in the Florida Keys to test for seasonal and interannual variability in seawater Sr/Ca, as well as collecting data from small reefs in the Virgin Islands to test the stability of seawater Sr/Ca under different geologic, hydrologic and hydrographic environments.

  18. High Precision Zinc Stable Isotope Measurement of Certified Biological Reference Materials Using the Double Spike Technique and Multiple Collector-ICP-MS.

    Science.gov (United States)

    Moore, Rebekah E T; Larner, Fiona; Coles, Barry J; Rehkämper, Mark

    2017-04-01

    Biological reference materials with well-characterised stable isotope compositions are lacking in the field of 'isotope biochemistry', which seeks to understand bodily processes that rely on essential metals by determining metal stable isotope ratios. Here, we present Zn stable isotope data for six biological reference materials with certified trace metal concentrations: fish muscle, bovine muscle, pig kidney, human hair, human blood serum and human urine. Replicate analyses of multiple aliquots of each material achieved reproducibilities (2sd) of 0.04-0.13‰ for δ 66/64 Zn (which denotes the deviation of the 66 Zn/ 64 Zn ratio of a sample from a pure Zn reference material in parts per 1000). This implies only very minor isotopic heterogeneities within the samples, rendering them suitable as quality control materials for Zn isotope analyses. This endorsement is reinforced by (i) the close agreement of our Zn isotope data for two of the samples (bovine muscle and human blood serum) to previously published results for different batches of the same material and (ii) the similarity of the isotopic data for the samples (δ 66/64 Zn ≈ -0.8 to 0.0‰) to previously published Zn isotope results for similar biological materials. Further tests revealed that the applied Zn separation procedure is sufficiently effective to enable accurate data acquisition even at low mass resolving power (M/ΔM ≈ 400), as measurements and analyses conducted at much higher mass resolution (M/ΔM ≈ 8500) delivered essentially identical results.

  19. Grain size effect on Sr and Nd isotopic compositions in eolian dust. Implications for tracing dust provenance and Nd model age

    International Nuclear Information System (INIS)

    Feng Jinliang; Zhu Liping; Zhen Xiaolin; Hu Zhaoguo

    2009-01-01

    Strontium (Sr) and neodymium (Nd) isotopic compositions enable identification of dust sources and reconstruction of atmospheric dispersal pathways. The Sr and Nd isotopic compositions in eolian dust change systematically with grain size in ways not yet fully understood. This study demonstrates the grain size effect on the Sr and Nd isotopic compositions in loess and 2006 dust fall, based on analyses of seven separated grain size fractions. The analytical results indicate that Sr isotopic ratios strongly depend on the grain size fractions in samples from all types of eolian dust. In contrast, the Nd isotopic ratios exhibit little variation in loess, although they vary significantly with grain size in samples from a 2006 dust fall. Furthermore, Nd model ages tend to increase with increasing grain size in samples from all types of eolian dust. Comparatively, Sr isotopic compositions exhibit high sensitively to wind sorting, while Nd isotopic compositions show greater sensitively to dust origin. The principal cause for the different patterns of Sr and Nd isotopic composition variability with grain size appears related to the different geochemical behaviors between rubidium (Rb) and Sr, and the similar geochemical behaviors between samarium (Sm) and Nd. The Nd isotope data indicate that the various grain size fractions in loess have similar origins for each sample. In contrast, various provenance components may separate into different grain size fractions for the studied 2006 dust fall. The Sr and Nd isotope compositions further confirm that the 2006 dust fall and Pleistocene loess in Beijing have different sources. The loess deposits found in Beijing and those found on the Chinese Loess Plateau also derive from different sources. Variations between Sr and Nd isotopic compositions and Nd model ages with grain size need to be considered when directly comparing analyses of eolian dust of different grain size. (author)

  20. Sr and Nd isotopic and trace element compositions of Quaternary volcanic centers of the Southern Andes

    Science.gov (United States)

    Futa, K.; Stern, C.R.

    1988-01-01

    Isotopic compositions of samples from six Quaternary volcanoes located in the northern and southern extremities of the Southern Volcanic Zone (SVZ, 33-46??S) of the Andes and from four centers in the Austral Volcanic Zone (AVZ, 49-54??S) range for 87Sr 86Sr from 0.70280 to 0.70591 and for 143Nd 144Nd from 0.51314 to 0.51255. The ranges are significantly greater than previously reported from the southern Andes but are different from the isotopic compositions of volcanoes in the central and northern Andes. Basalts and basaltic andesites from three centers just north of the Chile Rise-Trench triple junction have 87Sr 86Sr, 143Nd 144Nd, La Yb, Ba La, and Hf Lu that lie within the relatively restricted ranges of the basic magmas erupted from the volcanic centers as far north as 35??S in the SVZ of the Andes. The trace element and Sr and Nd isotopic characteristics of these magmas may be explained by source region contamination of subarc asthenosphere, with contaminants derived from subducted pelagic sediments and seawater-altered basalts by dehydration of subducted oceanic lithosphere. In the northern extremity of the SVZ between 33?? and 34??S, basaltic andesites and andesites have higher 87Sr 86Sr, Rb Cs, and Hf Lu, and lower 143Nd 144Nd than basalts and basaltic andesites erupted farther south in the SVZ, which suggests involvement of components derived from the continental crust. In the AVZ, the most primitive sample, high-Mg andesite from the southernmost volcanic center in the Andes (54??S) has Sr and Nd isotopic compositions and K Rb and Ba La similar to MORB. The high La Yb of this sample suggests formation by small degrees of partial melting of subducted MORB with garnet as a residue. Samples from centers farther north in the AVZ show a regionally regular northward increase in SiO2, K2O, Rb, Ba, Ba La, and 87Sr 86Sr and decrease in MgO, Sr, K Rb, Rb Cs, and 143Nd 144Nd, suggesting increasingly greater degrees of fractional crystallization and associated intra

  1. High precision timing in a FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Hoek, Matthias; Cardinali, Matteo; Dickescheid, Michael; Schlimme, Soeren; Sfienti, Concettina; Spruck, Bjoern; Thiel, Michaela [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet Mainz (Germany)

    2016-07-01

    A segmented highly precise start counter (FLASH) was designed and constructed at the Institute for Nuclear Physics in Mainz. Besides determining a precise reference time, a Time-of-Flight measurement can be performed with two identical FLASH units. Thus, particle identification can be provided for mixed hadron beam environments. The detector design is based on the detection of Cherenkov light produced in fused silica radiator bars with fast multi-anode MCP-PMTs. The segmentation of the radiator improves the timing resolution while allowing a coarse position resolution along one direction. Both, the arrival time and the Time-over-Threshold are determined by the readout electronics, which enables walk correction of the arrival time. The performance of two FLASH units was investigated in test experiments at the Mainz Microton (MAMI) using an electron beam with an energy of 855 MeV and at CERN's PS T9 beam line with a mixed hadron beam with momenta between 3-8 GeV/c. Effective Time-walk correction methods based on Time-over-Threshold were developed for the data analysis. The achieved Time-Of-Flight resolution after applying all corrections was found to be 70 ps. Furthermore, the PID and position resolution capabilities are discussed in this contribution.

  2. Clay mineralogical and Sr, Nd isotopic investigations in two deep-sea sediment cores from Northeast Indian Ocean

    International Nuclear Information System (INIS)

    Anil Babu, G.; Masood Ahmad, S.; Padmakumari, V.M.; Dayal, A.M.

    2004-01-01

    Sr and Nd isotopic studies in terrigenous component of the ocean sediments provide useful information about weathering patterns near source rock and climatic conditions existed on the continents. Variations in 87 Sr/ 86 Sr and 143 Nd/ 144 Nd isotopic ratios in clastic sediments depend on the source from the continents, volcanic input and circulation changes. The composition of clay minerals mainly depends on climate, geology and topography of the surrounding region. Chlorite and Illite are formed under physical weathering in arid cold climate and kaolinite and smectite are the characteristic products of chemical weathering in humid wet climatic conditions. Therefore, the variations in clay mineral composition in deep-sea sediments can be interpreted in terms of changes in the climatic conditions prevailed in the continental source areas

  3. The study of high precision neutron moisture gauge

    International Nuclear Information System (INIS)

    Liu Shengkang; Bao Guanxiong; Sang Hai; Zhu Yuzhen

    1993-01-01

    The principle, structure and calibration experiment of the high precision neutron moisture gauge (insertion type) are described. The gauge has been appraised. The precision of the measuring moisture of coke is lower than 0.5%, and the range of the measuring moisture is 2%-12%. The economic benefit of the gauge application is good

  4. Fingerprinting North Atlantic water masses near Iceland using Nd-isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Norbert [Institut fuer Umweltphysik, INF229, Heidelberg (Germany); Waldner, Astrid [Paul Scherrer Institute, Villigen (Switzerland); Montagna, Paolo [CNR - ISMAR, Bologna (Italy); Colin, Christophe [IDES, Universite de Paris-Sud, Orsay (France); Wu, Qiong [State Key Laboratory, Tongji University, Shanghai (China)

    2015-07-01

    The radiogenic {sup 143}Nd/{sup 144}Nd ratio of seawater is a valuable tracer of north Atlantic circulation pathways, driven by continental runoff (freshwater and Aeolian dust), boundary exchange and advection and thus mixing patterns. A region of particular interest in the North Atlantic is the overflow across the Iceland-Scotland Ridge injecting water from the Arctic Ocean into the Iceland basin (Iceland Scotland Overflow Water). However, Iceland itself constitutes a local source for Nd due to possible leaching of young volcanic basalts adding radiogenic {sup 143}Nd/{sup 144}Nd to seawater. We have conducted an intense survey of physical properties and Nd-isotope composition between Iceland and the Azores that allows to fingerprint different water masses of the North Atlantic through the {sup 143}Nd/{sup 144}Nd ratio and that demonstrates the very local influence of volcanic material to the seawater Nd cycle. A first local transect is achieved from the open ocean to the outflow of the Vatnajoekull glacier. Runoff influences seawater Nd in close vicinity (< 40 km near the outflow). A along shelf transect provide a similar observation. From Iceland to the Azores, however, water masses of the sub-tropical and sub-polar gyre are clearly distinguishable.

  5. Nd isotopes in French Phanerzoic shales: external vs. internal aspects of crustal evolution

    International Nuclear Information System (INIS)

    Michard, A.; Gurriet, P.; Soudant, M.; Alberede, F.; Ecole Nationale Superieure de Geologie Appliquee et de Prospection Miniere, 54 - Nancy

    1985-01-01

    Nd isotopic composition has been determined on shales of Paleozoic (Brittany and Languedoc) and Mesozoic (Lorraine) age. epsilonsub(Nd)(T) values range from -6 to -12 while Nd crustal residence ages are typically in excess over their stratigraphic ages by some 1.4 Ga. Exceptions to this rule are the sediments coeval with Hercynian, Caledonian and Cadomian orogenic events, the epsilonsub(Nd)(T) values of which suggest addition of mantle material to the sediment in the form of volcanoclastic detritus. In Brittany, this is confirmed by the local zircon chronology which provides upper intercepts of Concordia up to 800 m.y. in excess of Nd crustal residence ages. Comparison of crustal residence ages with stratigraphic ages through geologic time suggests a three stage history: a) for rocks older than 2 Ga, stratigraphic and crustal residence ages coincide, b) from 2 to 1 Ga, crustal residence ages level off at ca. 2 Ga and then c) decrease down to 1.4 Ga in recent sediments. Two extreme models can account for the observed variations: an internally driven model, in which variable quantities of mantle material are added to the crust, and an externally driven model, in which the rate of crustal recycling is low in the Archean but increases rapidly at the onset of the atmospheric oxygen buildup. (author)

  6. EVALUATION OF NEUTRON CROSS SECTIONS FOR A COMPLETE SET OF Nd ISOTOPES.

    Energy Technology Data Exchange (ETDEWEB)

    KIM,H.; HERMAN, M.; MUGHABGHAB, S.F.; OBLOZINSKY, P.; ROCHMAN, D.; LEE. Y.-O.

    2007-10-29

    Neutron cross sections for a complete set of Nd isotopes, {sup 142,143,144,145,146,147,148,150}Nd, were evaluated in the incident energy range from 10{sup -5} eV to 20 MeV. In the low energy region, including thermal and resolved resonances, our evaluations are based on the latest data published in the Atlas of Neutron Resonances. In the unresolved resonance region we performed additional evaluation by using the averages of the resolved resonances and adjusting them to the experimental data. In the fast neutron region, we used the nuclear reaction model code EMPIRE-2.19 validated against the experimental data. The results are compared to the existing nuclear data libraries, including ENDF/B-VI.8, JENDL-3.3 and JEFF-3.1, and to the available experimental data. The new evaluations are suitable for neutron transport calculations and they were adopted by the new evaluated nuclear data file of the United States, ENDF/B-VII.0, released in December 2006.

  7. Rb-Sr and Sm-Nd Isotopic Studies of Lunar Green and Orange Glasses

    Science.gov (United States)

    Shih, C.-Y.; Nyquist, L. E.; Reese, Y.

    2012-01-01

    Lunar volcanic glassy beads have been considered as quenched basaltic magmas derived directly from deep lunar mantle during fire-fountaining eruptions [1]. Since these sub-mm size glassy melt droplets were cooled in a hot gaseous medium during free flight [2], they have not been subject to mineral fractionations. Thus, they represent primary magmas and are the best samples for the investigation of the lunar mantle. Previously, we presented preliminary Rb- Sr and Sm-Nd isotopic results for green and orange glassy samples from green glass clod 15426,63 and orange soil 74220,44, respectively [3]. Using these isotopic data, initial Sr-87/Sr-86 and Nd ratios for these pristine mare glass sources can be calculated from their respective crystallization ages previously determined by other age-dating techniques. These isotopic data were used to evaluate the mineralogy of the mantle sources. In this report, we analyzed additional glassy samples in order to further characterize isotopic signatures of their source regions. Also, we'll postulate a relationship between these two major mare basalt source mineralogies in the context of lunar magma ocean dynamics.

  8. Fiber Scrambling for High Precision Spectrographs

    Science.gov (United States)

    Kaplan, Zachary; Spronck, J. F. P.; Fischer, D.

    2011-05-01

    The detection of Earth-like exoplanets with the radial velocity method requires extreme Doppler precision and long-term stability in order to measure tiny reflex velocities in the host star. Recent planet searches have led to the detection of so called "super-Earths” (up to a few Earth masses) that induce radial velocity changes of about 1 m/s. However, the detection of true Earth analogs requires a precision of 10 cm/s. One of the largest factors limiting Doppler precision is variation in the Point Spread Function (PSF) from observation to observation due to changes in the illumination of the slit and spectrograph optics. Thus, this stability has become a focus of current instrumentation work. Fiber optics have been used since the 1980's to couple telescopes to high-precision spectrographs, initially for simpler mechanical design and control. However, fiber optics are also naturally efficient scramblers. Scrambling refers to a fiber's ability to produce an output beam independent of input. Our research is focused on characterizing the scrambling properties of several types of fibers, including circular, square and octagonal fibers. By measuring the intensity distribution after the fiber as a function of input beam position, we can simulate guiding errors that occur at an observatory. Through this, we can determine which fibers produce the most uniform outputs for the severest guiding errors, improving the PSF and allowing sub-m/s precision. However, extensive testing of fibers of supposedly identical core diameter, length and shape from the same manufacturer has revealed the "personality” of individual fibers. Personality describes differing intensity patterns for supposedly duplicate fibers illuminated identically. Here, we present our results on scrambling characterization as a function of fiber type, while studying individual fiber personality.

  9. Signal or noise? Separating grain size-dependent Nd isotope variability from provenance shifts in Indus delta sediments, Pakistan

    Science.gov (United States)

    Jonell, T. N.; Li, Y.; Blusztajn, J.; Giosan, L.; Clift, P. D.

    2017-12-01

    Rare earth element (REE) radioisotope systems, such as neodymium (Nd), have been traditionally used as powerful tracers of source provenance, chemical weathering intensity, and sedimentary processes over geologic timescales. More recently, the effects of physical fractionation (hydraulic sorting) of sediments during transport have called into question the utility of Nd isotopes as a provenance tool. Is source terrane Nd provenance resolvable if sediment transport strongly induces noise? Can grain-size sorting effects be quantified? This study works to address such questions by utilizing grain size analysis, trace element geochemistry, and Nd isotope geochemistry of bulk and grain-size fractions (Pakistan. Here we evaluate how grain size effects drive Nd isotope variability and further resolve the total uncertainties associated with Nd isotope compositions of bulk sediments. Results from the Indus delta indicate bulk sediment ɛNd compositions are most similar to the <63 µm fraction as a result of strong mineralogical control on bulk compositions by silt- to clay-sized monazite and/or allanite. Replicate analyses determine that the best reproducibility (± 0.15 ɛNd points) is observed in the 125-250 µm fraction. The bulk and finest fractions display the worst reproducibility (±0.3 ɛNd points). Standard deviations (2σ) indicate that bulk sediment uncertainties are no more than ±1.0 ɛNd points. This argues that excursions of ≥1.0 ɛNd points in any bulk Indus delta sediments must in part reflect an external shift in provenance irrespective of sample composition, grain size, and grain size distribution. Sample standard deviations (2s) estimate that any terrigenous bulk sediment composition should vary no greater than ±1.1 ɛNd points if provenance remains constant. Findings from this study indicate that although there are grain-size dependent Nd isotope effects, they are minimal in the Indus delta such that resolvable provenance-driven trends can be

  10. Investigating sediment size distributions and size-specific Sm-Nd isotopes as paleoceanographic proxy in the North Atlantic Ocean: reconstructing past deep-sea current speeds since Last Glacial Maximum

    OpenAIRE

    Li, Yuting

    2017-01-01

    To explore whether the dispersion of sediments in the North Atlantic can be related to modern and past Atlantic Meridional Overturning Circulation (AMOC) flow speed, particle size distributions (weight%, Sortable Silt mean grain size) and grain-size separated (0–4, 4–10, 10–20, 20–30, 30–40 and 40–63 µm) Sm-Nd isotopes and trace element concentrations are measured on 12 cores along the flow-path of Western Boundary Undercurrent and in the central North Atlantic since the Last glacial Maximum ...

  11. High precision, rapid laser hole drilling

    Science.gov (United States)

    Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

    2013-04-02

    A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

  12. Hf-Nd isotope decoupling in the oceanic lithosphere: constraints from spinel peridotites from Oahu, Hawaii

    Science.gov (United States)

    Bizimis, Michael; Sen, Gautam; Salters, Vincent J. M.

    2004-01-01

    We present a detailed geochemical investigation on the Hf, Nd and Sr isotope compositions and trace and major element contents of clinopyroxene mineral separates from spinel lherzolite xenoliths from the island of Oahu, Hawaii. These peridotites are believed to represent the depleted oceanic lithosphere beneath Oahu, which is a residue of a MORB-related melting event some 80-100 Ma ago at a mid-ocean ridge. Clinopyroxenes from peridotites from the Salt Lake Crater (SLC) show a large range of Hf isotopic compositions, from ɛHf=12.2 (similar to the Honolulu volcanics series) to extremely radiogenic, ɛHf=65, at nearly constant 143Nd/ 144Nd ratios ( ɛNd=7-8). None of these samples show any isotopic evidence for interaction with Koolau-type melts. A single xenolith from the Pali vent is the only sample with Hf and Nd isotopic compositions that falls within the MORB field. The Hf isotopes correlate positively with the degree of depletion in the clinopyroxene (e.g. increasing Mg#, Cr#, decreasing Ti and heavy REE contents), but also with increasing Zr and Hf depletions relative to the adjacent REE in a compatibility diagram. The Lu/Hf isotope systematics of the SLC clinopyroxenes define apparent ages of 500 Ma or older and these compositions cannot be explained by mixing between any type of Hawaiian melts and the depleted Pacific lithosphere. Metasomatism of an ancient (e.g. 1 Ga or older) depleted peridotite protolith can, in principle, explain these apparent ages and the Nd-Hf isotope decoupling, but requires that the most depleted samples were subject to the least amount of metasomatism. Alternatively, the combined isotope, trace and major element compositions of these clinopyroxenes are best described by metasomatism of the 80-100 Ma depleted oceanic lithosphere by melts products of extensive mantle-melt interaction between Honolulu Volcanics-type melts and the depleted lithosphere.

  13. The neoproterozoic Goias magmatic arc, central Brazil: a review and new Sm-Nd isotopic data

    International Nuclear Information System (INIS)

    Pimentel, Marcio Martins; Fuck, Reinhardt Adolfo; Gioia, Simone Maria Costa Lima

    2000-01-01

    In this study we review the main characteristics and geochronological/isotopic data of metaigneous rocks of the juvenile Neoproterozoic Goias Magmatic Arc in central Brazil. Some new Sm-Nd isotopic data are also presented for both the southern (Arenopolis) and northern (Mara Rosa) sections of the arc. In the south, granitoids of the Choupana-Turvania area yielded a Sm-Nd whole-rock isochron age of 863± 97 Ma and e Nd (T) of +4.1 T D M model ages vary between 0.94 and 1.13 Ga. Metavolcanic rocks in the Pontalina region have a Sm-Nd whole rock isochron age of 762 ± 77 Ma and e Nd (T) of +2.9. T DM values are between 0.96 and 1.10 Ga. In the northern section of the Goias Arc, mylonitic gneisses of the Serra Azul ridge, an important N30E shear zone, were investigated and have a Sm-Nd isochron age of 3058 ± 120 Ma and initial e Nd value of ca.+ 2.1. This data suggests that the Serra Azul ridge might represent either a mylonitized fragment of the Archaen terranes exposed just to the south, or the sialic basement of the Araguaia Belt supracrustal, along the eastern margin of the Amazon Craton. The geochronological data available so far indicate a long history of arc formation and amalgamation on the western margin of the Sao Francisco-Congo continent during the Neoproterozoic. The history of convergence of continental masses is partially coeval with the fragmentation of Rodinia, indicating that the western margin (present geographic reference) of that continent occupied a peripheral setting in the Rodinia super continent. (author)

  14. Sr and Nd isotope geochemistry of coexisting alkaline magma series, Cantal, Massif Central, France

    International Nuclear Information System (INIS)

    Downes, H.

    1984-01-01

    Sr and Nd isotope analyses are presented for Tertiary continental alkaline volcanics from Cantal, Massif Central, France. The volcanics belong to two main magma series, silica-saturated and silica-undersaturated (with rare nephelinites). Trace element and isotopic data indicate a common source for the basic parental magmas of both major series; the nephelinites in contrast must have been derived from a mantle source which is isotopically and chemically distinct from that which gave rise to the basalts and basanites. 87 Sr/ 86 Sr initial ratios range from 0.7034 to 0.7056 in the main magma series (excluding rhyolites) and 143 Nd/ 144 Nd ratios vary between 0.512927 and 0.512669; both are correlated with increasing SiO 2 in the lavas. The data can be explained by a model of crustal contamination linked with fractional crystallisation. This indicates that crustal magma chambers are the sites of differentiation since only rarely do evolved magmas not show a crustal isotopic signature and conversely basic magmas have primitive isotopic ratios unless they contain obviuos crustal-derived xenocrysts. Potential contaminants include lower crustal granulites or partial melts of upper crustal units. Equal amounts of contamination are required for both magma series, refuting hypotheses of selective contamination of the silica-saturated series. The isotopic characteristics of the apparently primary nephelinite lavas demonstrates widespread heterogeneity in the mantle beneath Cantal. Some rhyolites, previously thought to be extremely contaminated or to be crustally derived, are shown to have undergone post-emplacement hydrothermal alteration. (orig.)

  15. The neoproterozoic Goias magmatic arc, central Brazil: a review and new Sm-Nd isotopic data

    Energy Technology Data Exchange (ETDEWEB)

    Pimentel, Marcio Martins; Fuck, Reinhardt Adolfo; Gioia, Simone Maria Costa Lima [Brasilia Univ., DF (Brazil). Inst. de Geociencias]. E-mail: marcio@unb.br

    2000-03-01

    In this study we review the main characteristics and geochronological/isotopic data of metaigneous rocks of the juvenile Neoproterozoic Goias Magmatic Arc in central Brazil. Some new Sm-Nd isotopic data are also presented for both the southern (Arenopolis) and northern (Mara Rosa) sections of the arc. In the south, granitoids of the Choupana-Turvania area yielded a Sm-Nd whole-rock isochron age of 863{+-} 97 Ma and e{sub Nd} (T) of +4.1 T{sub D}M model ages vary between 0.94 and 1.13 Ga. Metavolcanic rocks in the Pontalina region have a Sm-Nd whole rock isochron age of 762 {+-} 77 Ma and e{sub Nd} (T) of +2.9. T {sub DM} values are between 0.96 and 1.10 Ga. In the northern section of the Goias Arc, mylonitic gneisses of the Serra Azul ridge, an important N30E shear zone, were investigated and have a Sm-Nd isochron age of 3058 {+-} 120 Ma and initial e{sub Nd} value of ca.+ 2.1. This data suggests that the Serra Azul ridge might represent either a mylonitized fragment of the Archaen terranes exposed just to the south, or the sialic basement of the Araguaia Belt supracrustal, along the eastern margin of the Amazon Craton. The geochronological data available so far indicate a long history of arc formation and amalgamation on the western margin of the Sao Francisco-Congo continent during the Neoproterozoic. The history of convergence of continental masses is partially coeval with the fragmentation of Rodinia, indicating that the western margin (present geographic reference) of that continent occupied a peripheral setting in the Rodinia super continent. (author)

  16. High-Precision Computation and Mathematical Physics

    International Nuclear Information System (INIS)

    Bailey, David H.; Borwein, Jonathan M.

    2008-01-01

    At the present time, IEEE 64-bit floating-point arithmetic is sufficiently accurate for most scientific applications. However, for a rapidly growing body of important scientific computing applications, a higher level of numeric precision is required. Such calculations are facilitated by high-precision software packages that include high-level language translation modules to minimize the conversion effort. This paper presents a survey of recent applications of these techniques and provides some analysis of their numerical requirements. These applications include supernova simulations, climate modeling, planetary orbit calculations, Coulomb n-body atomic systems, scattering amplitudes of quarks, gluons and bosons, nonlinear oscillator theory, Ising theory, quantum field theory and experimental mathematics. We conclude that high-precision arithmetic facilities are now an indispensable component of a modern large-scale scientific computing environment.

  17. A sublimation technique for high-precision measurements of δ13CO2 and mixing ratios of CO2 and N2O from air trapped in ice cores

    Directory of Open Access Journals (Sweden)

    H. Fischer

    2011-07-01

    Full Text Available In order to provide high precision stable carbon isotope ratios (δ13CO2 or δ13C of CO2 from small bubbly, partially and fully clathrated ice core samples we developed a new method based on sublimation coupled to gas chromatography-isotope ratio mass spectrometry (GC-IRMS. In a first step the trapped air is quantitatively released from ~30 g of ice and CO2 together with N2O are separated from the bulk air components and stored in a miniature glass tube. In an off-line step, the extracted sample is introduced into a helium carrier flow using a minimised tube cracker device. Prior to measurement, N2O and organic sample contaminants are gas chromatographically separated from CO2. Pulses of a CO2/N2O mixture are admitted to the tube cracker and follow the path of the sample through the system. This allows an identical treatment and comparison of sample and standard peaks. The ability of the method to reproduce δ13C from bubble and clathrate ice is verified on different ice cores. We achieve reproducibilities for bubble ice between 0.05 ‰ and 0.07 ‰ and for clathrate ice between 0.05 ‰ and 0.09 ‰ (dependent on the ice core used. A comparison of our data with measurements on bubble ice from the same ice core but using a mechanical extraction device shows no significant systematic offset. In addition to δ13C, the CO2 and N2O mixing ratios can be volumetrically derived with a precision of 2 ppmv and 8 ppbv, respectively.

  18. Multiple enrichment of the Carpathian-Pannonian mantle: Pb-Sr-Nd isotope and trace element constraints

    Science.gov (United States)

    Rosenbaum, Jeffrey M.; Wilson, Marjorie; Downes, Hilary

    1997-07-01

    Pb isotope compositions of acid-leached clinopyroxene and amphibole mineral separates from spinel peridotite mantle xenoliths entrained in Tertiary-Quaternary alkali basalts from the Carpathian-Pannonian Region of eastern Europe provide important constraints on the processes of metasomatic enrichment of the mantle lithosphere in an extensional tectonic setting associated with recent subduction. Principal component analysis of Pb-Sr-Nd isotope and rare earth element compositions of the pyroxenes is used to identify the geochemical characteristics of the original lithospheric mantle protolith and a spectrum of infiltrating metasomatic agents including subduction-related aqueous fluids and silicate melts derived from a subduction-modified mantle wedge which contains a St. Helena-type (HIMU) plume component. The mantle protolith is highly depleted relative to mid-ocean ridge basalt-source mantle with Pb-Nd-Sr isotope compositions consistent with an ancient depletion event. Silicate melt infiltration into the protolith accounts for the primary variance in the Pb-Sr-Nd isotope compositions of the xenoliths and has locally generated metasomatic amphibole. Infiltration of aqueous fluids has introduced radiogenic Pb and Sr without significantly perturbing the rare earth element signature of the protolith. The Pb isotope compositions of the fluid-modified xenoliths suggest that they reacted with aqueous fluids released from a subduction zone which had equilibrated with sediment derived from an ancient basement terrain. We propose a model for mantle lithosphere evolution consistent with available textural and geochemical data for the xenolith population. The Pb-Sr-Nd isotope compositions of both alkaline mafic magmas and rare, subduction-related, calc-alkaline basaltic andesites from the region provide important constraints for the nature of the asthenospheric mantle wedge and confirm the presence of a HIMU plume component. These silicate melts contribute to the metasomatism

  19. Sources and processes affecting the distribution of dissolved Nd isotopes and concentrations in the West Pacific

    Science.gov (United States)

    Behrens, Melanie K.; Pahnke, Katharina; Schnetger, Bernhard; Brumsack, Hans-Jürgen

    2018-02-01

    In the Atlantic, where deep circulation is vigorous, the dissolved neodymium (Nd) isotopic composition (expressed as ɛNd) is largely controlled by water mass mixing. In contrast, the factors influencing the ɛNd distribution in the Pacific, marked by sluggish circulation, is not clear yet. Indication for regional overprints in the Pacific is given based on its bordering volcanic islands. Our study aims to clarify the impact and relative importance of different Nd sources (rivers, volcanic islands), vertical (bio)geochemical processes and lateral water mass transport in controlling dissolved ɛNd and Nd concentration ([Nd]) distributions in the West Pacific between South Korea and Fiji. We find indication for unradiogenic continental input from South Korean and Chinese rivers to the East China Sea. In the tropical West Pacific, volcanic islands supply Nd to surface and subsurface waters and modify their ɛNd to radiogenic values of up to +0.7. These radiogenic signatures allow detailed tracing of currents flowing to the east and differentiation from westward currents with open ocean Pacific ɛNd composition in the complex tropical Pacific zonal current system. Modified radiogenic ɛNd of West Pacific intermediate to bottom waters upstream or within our section also indicates non-conservative behavior of ɛNd due to boundary exchange at volcanic island margins, submarine ridges, and with hydrothermal particles. Only subsurface to deep waters (3000 m) in the open Northwest Pacific show conservative behavior of ɛNd. In contrast, we find a striking correlation of extremely low (down to 2.77 pmol/kg Nd) and laterally constant [Nd] with the high-salinity North and South Pacific Tropical Water, indicating lateral transport of preformed [Nd] from the North and South Pacific subtropical gyres into the study area. This observation also explains the previously observed low subsurface [Nd] in the tropical West Pacific. Similarly, Western South Pacific Central Water, Antarctic

  20. Crustal evolution of South American Platform based on Sm-Nd isotope geochemistry

    International Nuclear Information System (INIS)

    Sato, Kei

    1998-01-01

    Sm-Nd isotopic systematics is relevant to the topics of origin and evolution the of continental crust, where model ages refer to the time when crustal material was differentiated from the upper mantle. Alternative interpretations are due to a lack of adequate information on crustal processes and the variable composition of the mantle sources. The Sm-Nd methods are presented, and applied on rock materials from the South American Platform. The main conclusions indicate juvenile accretion with higher growth rates (peaks), around 3.7-3.5 Ga (∼ 0.5% in volume), 3.1 - 2.9 Ga (∼16%), 2.7 - 2.6 (∼ 9%), 2.2 - 1.9 (35%) and 1.3-1.0 (7%). The continental growth curve indicates that about 35 % of the crust was formed by 2.5 Ga, 88% by 1.8 Ga and 99% by 1.0 Ga, and the remaining ∼ 1 % was added in the Phanerozoic. Rapid crustal growth occurred between 2.2 and 1.9 Ga. The main period of continental crust formation occurred during the Paleoproterozoic, corresponding to 54 % in volume. Sm-Nd model ages, when compared with the crystallisation ages of granitoid rocks, furnish a rough estimate of juvenile vs. reworked material. Within the South American Platform about 45% of juvenile continental crust is still preserved within tectonic provinces of different ages. The remainder represents continental crust reworked in younger tectono-thermal events. In particular crustal reworking was predominating over juvenile accretion during Meso-Neoproterozoic. The Transbrasiliano Lineament is a megasuture, active in the Neoproterozoic, which separates a large northwestern mass, including the Amazonian and Sao Luis Cratons, from a southeastern mass, formed by a collage of cratonic fragments, of which the Sao Francisco and Rio de La Plata are the largest. The crustal evolutions of these two large continental masses are considered individually, and can be resumed following form: I - Old Archean rocks (>3.4 Ga) are found only within the south-eastern part (Gaviao Block, Contendas

  1. Geographical variations in Sr and Nd isotopic ratios of cryoconite on Asian glaciers

    International Nuclear Information System (INIS)

    Nagatsuka, Naoko; Takeuchi, Nozomu; Nakano, Takanori; Shin, Kicheol; Kokado, Emi

    2014-01-01

    Cryoconite is a dark-coloured surface dust deposited on glaciers that consists of wind-blown mineral particles, as well as organic matter derived from microbes living on glaciers. In this paper, we analyse the Sr and Nd isotopic ratios of four mineral fractions (i.e., the saline, carbonate, phosphate, and silicate mineral fractions), as well as the organic fraction, of cryoconite samples obtained from six Asian glaciers (the Altai, Pamir, Tien Shan, Qillian Shan, and Himalayan regions), and discuss their geographical variations in terms of the geological origins of the mineral particles and the biogeochemical processes on the glaciers. The silicate mineral fraction showed lower Sr and higher Nd ratios for the glaciers located to the north (Altai, 87 Sr/ 86 Sr: 0.713 490–0.715 284, εNd(0): −6.4 to −5.6), while higher Sr and lower Nd ratios for the glaciers located to the south (Himalayas, 87 Sr/ 86 Sr: 0.740 121–0.742 088, εNd(0): −16.4 to −15.7); the ratios were similar to those of desert sand, loess, and river sediments in the respective regions of the glaciers. This result suggests that the silicate minerals within the cryoconites were derived from different sources depending on the geographical locations of the glaciers. The isotopic ratios of the saline, carbonate, and phosphate mineral fractions were distinct from those of the silicate fraction, and were similar to those of evaporites and apatite deposits from the Asian deserts, but also varied geographically, indicating that they are likely to reflect their geological origin. The Sr isotopic ratios of the organic fraction were similar to those of the saline and carbonate fractions from glaciers in the central area (Tien Shan and Qillian Shan), but were higher than those of the saline and carbonate fractions, and lower than the phosphate mineral fraction, in the northern and southern areas. The ratios of organic fraction may be determined from the mixing ratio of calcium sources

  2. Strategy for Realizing High-Precision VUV Spectro-Polarimeter

    Science.gov (United States)

    Ishikawa, R.; Narukage, N.; Kubo, M.; Ishikawa, S.; Kano, R.; Tsuneta, S.

    2014-12-01

    Spectro-polarimetric observations in the vacuum ultraviolet (VUV) range are currently the only means to measure magnetic fields in the upper chromosphere and transition region of the solar atmosphere. The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) aims to measure linear polarization at the hydrogen Lyman- α line (121.6 nm). This measurement requires a polarization sensitivity better than 0.1 %, which is unprecedented in the VUV range. We here present a strategy with which to realize such high-precision spectro-polarimetry. This involves the optimization of instrument design, testing of optical components, extensive analyses of polarization errors, polarization calibration of the instrument, and calibration with onboard data. We expect that this strategy will aid the development of other advanced high-precision polarimeters in the UV as well as in other wavelength ranges.

  3. Weak gravitational lensing towards high-precision cosmology

    International Nuclear Information System (INIS)

    Berge, Joel

    2007-01-01

    This thesis aims at studying weak gravitational lensing as a tool for high-precision cosmology. We first present the development and validation of a precise and accurate tool for measuring gravitational shear, based on the shapelets formalism. We then use shapelets on real images for the first time, we analyze CFHTLS images, and combine them with XMM-LSS data. We measure the normalisation of the density fluctuations power spectrum σ 8 , and the one of the mass-temperature relation for galaxy clusters. The analysis of the Hubble space telescope COSMOS field confirms our σ 8 measurement and introduces tomography. Finally, aiming at optimizing future surveys, we compare the individual and combined merits of cluster counts and power spectrum tomography. Our results demonstrate that next generation surveys will allow weak lensing to yield its full potential in the high-precision cosmology era. (author) [fr

  4. High precision detector robot arm system

    Science.gov (United States)

    Shu, Deming; Chu, Yong

    2017-01-31

    A method and high precision robot arm system are provided, for example, for X-ray nanodiffraction with an X-ray nanoprobe. The robot arm system includes duo-vertical-stages and a kinematic linkage system. A two-dimensional (2D) vertical plane ultra-precision robot arm supporting an X-ray detector provides positioning and manipulating of the X-ray detector. A vertical support for the 2D vertical plane robot arm includes spaced apart rails respectively engaging a first bearing structure and a second bearing structure carried by the 2D vertical plane robot arm.

  5. Hydrothermal sediments as a potential record of seawater Nd isotope compositions: The Rainbow vent site (36°14'N, Mid-Atlantic Ridge)

    Science.gov (United States)

    Chavagnac, ValéRie; Palmer, Martin R.; Milton, J. Andrew; Green, Darryl R. H.; German, Christopher R.

    2006-09-01

    Geochemical compositions and Sr and Nd isotopes were measured in two cores collected ˜2 and 5 km from the Rainbow hydrothermal vent site on the Mid-Atlantic Ridge. Overall, the cores record enrichments in Fe and other metals from hydrothermal fallout, but sequential dissolution of the sediments allows discrimination between a leach phase (easily leachable) and a residue phase (refractory). The oxy-anion and transition metal distribution combined with rare earth element (REE) patterns suggest that (1) the leach fraction is a mixture of biogenic carbonate and hydrothermal Fe-Mn oxy-hydroxide with no significant contribution from detrital material and (2) >99.5% of the REE content of the leach fraction is of seawater origin. In addition, the leach fraction has an average 87Sr/86Sr ratio indistinguishable from modern seawater at 0.70916. Although we lack the ɛNd value of present-day deep water at the Rainbow vent site, we believe that the REE budget of the leach fraction is predominantly of seawater origin. We suggest therefore that the leach fraction provides a record of local seawater ɛNd values. Nd isotope data from these cores span the period of 4-14 ka (14C ages) and yield ɛNd values for North East Atlantic Deep Water (NEADW) that are higher (-9.3 to -11.1) than those observed in the nearby Madeira Abyssal Plain from the same depth (-12.4 ± 0.9). This observation suggests that either the Iceland-Scotland Overflow Water (ISOW) and Lower Deep Water contributions to the formation of NEADW are higher along the Mid-Atlantic Ridge than in the surrounding basins or that the relative proportion of ISOW was higher during this period than is observed today. This study indicates that hydrothermal sediments have the potential to provide a higher-resolution record of deep water ɛNd values, and hence deepwater circulation patterns in the oceans, than is possible from other types of sediments.

  6. High-precision drop shape analysis (HPDSA) of quasistatic contact angles on silanized silicon wafers with different surface topographies during inclining-plate measurements: Influence of the surface roughness on the contact line dynamics

    International Nuclear Information System (INIS)

    Heib, F.; Hempelmann, R.; Munief, W.M.; Ingebrandt, S.; Fug, F.; Possart, W.; Groß, K.; Schmitt, M.

    2015-01-01

    Highlights: • Analysis of the triple line motion on surfaces with nanoscale surface topographies. • Analysis of the triple line motion is performed in sub-pixel resolution. • A special fitting and statistical approach for contact angle analysis is applied. • The analyses result set of contact angle data which is independent of “user-skills”. • Characteristically density distributions in dependence on the surface properties. - Abstract: Contact angles and wetting of solid surfaces are strongly influenced by the physical and chemical properties of the surfaces. These influence quantities are difficult to distinguish from each other if contact angle measurements are performed by measuring only the advancing θ a and the receding θ r contact angle. In this regard, time-dependent water contact angles are measured on two hydrophobic modified silicon wafers with different physical surface topographies. The first surface is nearly atomically flat while the second surface is patterned (alternating flat and nanoscale rough patterns) which is synthesized by a photolithography and etching procedure. The different surface topographies are characterized with atomic force microscopy (AFM), Fourier transform infrared reflection absorption spectroscopy (FTIRRAS) and Fourier transform infrared attenuated total reflection spectroscopy (FTIR-ATR). The resulting set of contact angle data obtained by the high-precision drop shape analysis approach is further analyzed by a Gompertzian fitting procedure and a statistical counting procedure in dependence on the triple line velocity. The Gompertzian fit is used to analyze overall properties of the surface and dependencies between the motion on the front and the back edge of the droplets. The statistical counting procedure results in the calculation of expectation values E(p) and standard deviations σ(p) for the inclination angle φ, contact angle θ, triple line velocity vel and the covered distance of the triple line dis

  7. High-precision drop shape analysis (HPDSA) of quasistatic contact angles on silanized silicon wafers with different surface topographies during inclining-plate measurements: Influence of the surface roughness on the contact line dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Heib, F., E-mail: f.heib@mx.uni-saarland.de [Department of Physical Chemistry, Saarland University, 66123 Saarbrücken (Germany); Hempelmann, R. [Department of Physical Chemistry, Saarland University, 66123 Saarbrücken (Germany); Munief, W.M.; Ingebrandt, S. [Department of Informatics and Microsystem Technology, University of Applied Sciences, Kaiserslautern, 66482 Zweibrücken (Germany); Fug, F.; Possart, W. [Department of Adhesion and Interphases in Polymers, Saarland University, 66123 Saarbrücken (Germany); Groß, K.; Schmitt, M. [Department of Physical Chemistry, Saarland University, 66123 Saarbrücken (Germany)

    2015-07-01

    Highlights: • Analysis of the triple line motion on surfaces with nanoscale surface topographies. • Analysis of the triple line motion is performed in sub-pixel resolution. • A special fitting and statistical approach for contact angle analysis is applied. • The analyses result set of contact angle data which is independent of “user-skills”. • Characteristically density distributions in dependence on the surface properties. - Abstract: Contact angles and wetting of solid surfaces are strongly influenced by the physical and chemical properties of the surfaces. These influence quantities are difficult to distinguish from each other if contact angle measurements are performed by measuring only the advancing θ{sub a} and the receding θ{sub r} contact angle. In this regard, time-dependent water contact angles are measured on two hydrophobic modified silicon wafers with different physical surface topographies. The first surface is nearly atomically flat while the second surface is patterned (alternating flat and nanoscale rough patterns) which is synthesized by a photolithography and etching procedure. The different surface topographies are characterized with atomic force microscopy (AFM), Fourier transform infrared reflection absorption spectroscopy (FTIRRAS) and Fourier transform infrared attenuated total reflection spectroscopy (FTIR-ATR). The resulting set of contact angle data obtained by the high-precision drop shape analysis approach is further analyzed by a Gompertzian fitting procedure and a statistical counting procedure in dependence on the triple line velocity. The Gompertzian fit is used to analyze overall properties of the surface and dependencies between the motion on the front and the back edge of the droplets. The statistical counting procedure results in the calculation of expectation values E(p) and standard deviations σ(p) for the inclination angle φ, contact angle θ, triple line velocity vel and the covered distance of the triple

  8. System and method for high precision isotope ratio destructive analysis

    Science.gov (United States)

    Bushaw, Bruce A; Anheier, Norman C; Phillips, Jon R

    2013-07-02

    A system and process are disclosed that provide high accuracy and high precision destructive analysis measurements for isotope ratio determination of relative isotope abundance distributions in liquids, solids, and particulate samples. The invention utilizes a collinear probe beam to interrogate a laser ablated plume. This invention provides enhanced single-shot detection sensitivity approaching the femtogram range, and isotope ratios that can be determined at approximately 1% or better precision and accuracy (relative standard deviation).

  9. High-precision measurement of phenylalanine δ15N values for environmental samples: a new approach coupling high-pressure liquid chromatography purification and elemental analyzer isotope ratio mass spectrometry.

    Science.gov (United States)

    Broek, Taylor A B; Walker, Brett D; Andreasen, Dyke H; McCarthy, Matthew D

    2013-11-15

    Compound-specific isotope analysis of individual amino acids (CSI-AA) is a powerful new tool for tracing nitrogen (N) source and transformation in biogeochemical cycles. Specifically, the δ(15)N value of phenylalanine (δ(15)N(Phe)) represents an increasingly used proxy for source δ(15)N signatures, with particular promise for paleoceanographic applications. However, current derivatization/gas chromatography methods require expensive and relatively uncommon instrumentation, and have relatively low precision, making many potential applications impractical. A new offline approach has been developed for high-precision δ(15)N measurements of amino acids (δ(15)N(AA)), optimized for δ(15)N(Phe) values. Amino acids (AAs) are first purified via high-pressure liquid chromatography (HPLC), using a mixed-phase column and automated fraction collection. The δ(15)N values are determined via offline elemental analyzer-isotope ratio mass spectrometry (EA-IRMS). The combined HPLC/EA-IRMS method separated most protein AAs with sufficient resolution to obtain accurate δ(15)N values, despite significant intra-peak isotopic fractionation. For δ(15)N(Phe) values, the precision was ±0.16‰ for standards, 4× better than gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS; ±0.64‰). We also compared a δ(15)N(Phe) paleo-record from a deep-sea bamboo coral from Monterey Bay, CA, USA, using our method versus GC/C/IRMS. The two methods produced equivalent δ(15)N(Phe) values within error; however, the δ(15)N(Phe) values from HPLC/EA-IRMS had approximately twice the precision of GC/C/IRMS (average stdev of 0.27‰ ± 0.14‰ vs 0.60‰ ± 0.20‰, respectively). These results demonstrate that offline HPLC represents a viable alternative to traditional GC/C/IMRS for δ(15)N(AA) measurement. HPLC/EA-IRMS is more precise and widely available, and therefore useful in applications requiring increased precision for data interpretation (e.g. δ(15)N paleoproxies

  10. Evidence of a connection between the Atlantic and Mediterranean during the Messinian Salinity Crisis from Pb and Nd isotopes

    Science.gov (United States)

    Modestou, Sevasti; Gutjahr, Marcus; Fietzke, Jan; Rodés, Ángel; Frank, Martin; Bolhão Muiños, Susana; Ellam, Rob; Flecker, Rachel

    2014-05-01

    Prior to the opening of the Gibraltar Strait at 5.33 Ma, the Betic (southern Spain) and Rifian (northern Morocco) marine palaeocorridors linked the Mediterranean to the Atlantic. Although the central regions of these corridors have been heavily eroded due to uplift, evidence published to date indicates that both closed before the onset of the Messinian Salinity Crisis (MSC; 5.97 to 5.33 Ma [1, 2]). However, pre-MSC corridor closure presents a paradox, as the volume of halite deposited within the Mediterranean basin requires several times the volume of seawater contained in the basin itself. In this regard, radiogenic isotopes such as Sr, Pb, and Nd can provide key information about the timing of exchange through the Betic and Rifian palaeogateways. Due to the resolvable isotopic difference in Nd isotope signatures of outgoing Mediterranean and incoming Atlantic water masses, demonstrated both for the present day as well as the past environment, this isotope system can be used to identify exchange between these two water bodies. Although less well constrained to date, the Pb isotope system can be used in a similar manner due to its short residence time in seawater and interbasin variability. A high resolution Pb isotope record extracted using laser ablation from ferromanganese crust 3514-6 (recovered from the Lion Seamount, NE Atlantic, water depth 690-940 m) indicates a relatively constant Pb isotope signature before, during and after the MSC period. The previously published [3] Nd isotope record of crust 3514-6 corroborates that the crust was deposited in a current distinct from NE Atlantic Deep water or Antarctic Intermediate Water, the principal currents in the region of the Lion Seamount. The combined Pb and Nd isotope evolution suggests that Mediterranean Outflow Water (MOW) was continuously advected into the NE Atlantic during and after the MSC. Furthermore, preliminary Nd isotope records from Late Miocene sediments collected in the Sorbas Basin, Spain

  11. Calcium-aluminum-rich inclusions with fractionation and unidentified nuclear effects (FUN CAIs): II. Heterogeneities of magnesium isotopes and 26Al in the early Solar System inferred from in situ high-precision magnesium-isotope measurements

    Science.gov (United States)

    Park, Changkun; Nagashima, Kazuhide; Krot, Alexander N.; Huss, Gary R.; Davis, Andrew M.; Bizzarro, Martin

    2017-03-01

    Calcium-aluminum-rich inclusions with isotopic mass fractionation effects and unidentified nuclear isotopic anomalies (FUN CAIs) have been studied for more than 40 years, but their origins remain enigmatic. Here we report in situ high precision measurements of aluminum-magnesium isotope systematics of FUN CAIs by secondary ion mass spectrometry (SIMS). Individual minerals were analyzed in six FUN CAIs from the oxidized CV3 carbonaceous chondrites Axtell (compact Type A CAI Axtell 2271) and Allende (Type B CAIs C1 and EK1-4-1, and forsterite-bearing Type B CAIs BG82DH8, CG-14, and TE). Most of these CAIs show evidence for excess 26Mg due to the decay of 26Al. The inferred initial 26Al/27Al ratios [(26Al/27Al)0] and the initial magnesium isotopic compositions (δ26Mg0) calculated using an exponential law with an exponent β of 0.5128 are (3.1 ± 1.6) × 10-6 and 0.60 ± 0.10‰ (Axtell 2271), (3.7 ± 1.5) × 10-6 and -0.20 ± 0.05‰ (BG82DH8), (2.2 ± 1.1) × 10-6 and -0.18 ± 0.05‰ (C1), (2.3 ± 2.4) × 10-5 and -2.23 ± 0.37‰ (EK1-4-1), (1.5 ± 1.1) × 10-5 and -0.42 ± 0.08‰ (CG-14), and (5.3 ± 0.9) × 10-5 and -0.05 ± 0.08‰ (TE) with 2σ uncertainties. We infer that FUN CAIs recorded heterogeneities of magnesium isotopes and 26Al in the CAI-forming region(s). Comparison of 26Al-26Mg systematics, stable isotope (oxygen, magnesium, calcium, and titanium) and trace element studies of FUN and non-FUN igneous CAIs indicates that there is a continuum among these CAI types. Based on these observations and evaporation experiments on CAI-like melts, we propose a generic scenario for the origin of igneous (FUN and non-FUN) CAIs: (i) condensation of isotopically normal solids in an 16O-rich gas of approximately solar composition; (ii) formation of CAI precursors by aggregation of these solids together with variable abundances of isotopically anomalous grains-possible carriers of unidentified nuclear (UN) effects; and (iii) melt evaporation of these precursors

  12. Tracing subduction zone fluid-rock interactions using trace element and Mg-Sr-Nd isotopes

    Science.gov (United States)

    Wang, Shui-Jiong; Teng, Fang-Zhen; Li, Shu-Guang; Zhang, Li-Fei; Du, Jin-Xue; He, Yong-Sheng; Niu, Yaoling

    2017-10-01

    Slab-derived fluids play a key role in mass transfer and elemental/isotopic exchanges in subduction zones. The exhumation of deeply subducted crust is achieved via a subduction channel where fluids from various sources are abundant, and thus the chemical/isotopic compositions of these rocks could have been modified by subduction-zone fluid-rock interactions. Here, we investigate the Mg isotopic systematics of eclogites from southwestern Tianshan, in conjunction with major/trace element and Sr-Nd isotopes, to characterize the source and nature of fluids and to decipher how fluid-rock interactions in subduction channel might influence the Mg isotopic systematics of exhumed eclogites. The eclogites have high LILEs (especially Ba) and Pb, high initial 87Sr/86Sr (up to 0.7117; higher than that of coeval seawater), and varying Ni and Co (mostly lower than those of oceanic basalts), suggesting that these eclogites have interacted with metamorphic fluids mainly released from subducted sediments, with minor contributions from altered oceanic crust or altered abyssal peridotites. The positive correlation between 87Sr/86Sr and Pb* (an index of Pb enrichment; Pb* = 2*PbN/[CeN + PrN]), and the decoupling relationships and bidirectional patterns in 87Sr/86Sr-Rb/Sr, Pb*-Rb/Sr and Pb*-Ba/Pb spaces imply the presence of two compositionally different components for the fluids: one enriched in LILEs, and the other enriched in Pb and 87Sr/86Sr. The systematically heavier Mg isotopic compositions (δ26Mg = - 0.37 to + 0.26) relative to oceanic basalts (- 0.25 ± 0.07) and the roughly negative correlation of δ26Mg with MgO for the southwestern Tianshan eclogites, cannot be explained by inheritance of Mg isotopic signatures from ancient seafloor alteration or prograde metamorphism. Instead, the signatures are most likely produced by fluid-rock interactions during the exhumation of eclogites. The high Rb/Sr and Ba/Pb but low Pb* eclogites generally have high bulk-rock δ26Mg values

  13. Hf-Nd Isotopic Correlation in the Deccan Flood Basalt Province

    Science.gov (United States)

    Saha, A.; Basu, A. R.; Barling, J.; Anbar, A. D.; Hooper, P. R.

    2001-12-01

    Hafnium isotopes along with other isotopic and geochemical characteristics, including incompatible trace elements, of several of the lower formations of the Deccan Flood Basalt Province were analyzed to characterize petrogenesis of different tholeiitic lava suites, especially with respect to potential mantle and crustal sources. The rare earth elements of the different formations (from top to bottom- Mahabaleshwar, Ambenali, Bushe, Khandala and Neral) all show an LREE-enriched signature, concentrations varying between 30 to 60 times chondrite for La. (La/Lu)n values range from 4.1 to above 8 with the exception of Ambenali, which has a less LREE-enriched signature with (La/Lu)n values ranging between 3.6 to 5.3. Hafnium isotopic data of the lower formations of the Deccan show initial \\epsilonHf(T) values covering a range from -3 to -28. 176Lu/177Hf varies between 0.20 to 0.70. f(Lu/Hf) varies within a narrow range, between -0.90 to -0.97 while f(Sm/Nd) ranges from -0.84 to -0.86. Bushe gives the lowest range of \\epsilonHf(T) from -21 to -28 with the corresponding \\epsilonNd(T) varying between -4.0 and -16.9, while Khandala for almost the same range of neodymium isotopic values has \\epsilonHf(T) between -11 and -15. The \\epsilonHf(T) values of Neral is in between those of Khandala and Bushe, around -19. Ambenali, has the narrowest range with \\epsilonHf(T) of -3 and \\epsilonNd(T) between 3 and 5. The Ambenali suite reflects the least contaminated of the Deccan suite of lavas as analyzed here and previously confirmed by other isotopic studies. In Hf-Nd isotope correlation plot, the lower Deccan formations of Neral, Khandala and Bushe define individual subparallel arrays that are shallower than the oceanic basalt array and the overall terrestrial array, including the crustal array, although the bulk of the lower formation data fall within the crustal array of Vervoort et al (1999). From these subparallel Hf-Nd arrays, it is evident that the other end

  14. Digitalization of highly precise fluxgate magnetometers

    DEFF Research Database (Denmark)

    Cerman, Ales; Kuna, A.; Ripka, P.

    2005-01-01

    This paper describes the theory behind all three known ways of digitalizing the fluxgate magnetometers: analogue magnetometers with digitalized output using high resolution ADC, application of the delta-sigma modulation to the sensor feedback loop and fully digital signal detection. At present time...... the Delta-Sigma ADCs are mostly used for the digitalization of the highly precise fluxgate magnetorneters. The relevant part of the paper demonstrates some pitfalls of their application studied during the design of the magnetometer for the new Czech scientific satellite MIMOSA. The part discussing...... the application of the A-E modulation to the sensor feedback loop theoretically derives the main advantage of this method-increasing of the modulation order and shows its real potential compared to the analog magnetometer with consequential digitalization. The comparison is realized on the modular magnetometer...

  15. Reassessment of the origin of the Dun Mountain Ophiolite, New Zealand : Nd-isotopic and geochemical evolution of magma suites

    International Nuclear Information System (INIS)

    Sivell, W.J.; McCulloch, M.T.

    2000-01-01

    Magmatic suites with contrasting isotopic and geochemical compositions, sequentially emplaced in different tectonic regimes, comprise the Dun Mountain Ophiolite Belt (DMOB), New Zealand. At D'Urville Island, the northernmost exposure of the DMOB, earliest erupted (stage 1) pillow basalts ε Nd (T) = +6.3 to +7.5, and are incompatible element enriched, like basalts from geochemically anomalous ridge segments. Overlying stage 2 basalts (sheeted flows) show a narrow range of ε Nd (T) = +8.3 + or -0.2, with chemical characteristics of depleted backarc basin basalts. These rocks are intruded by mafic to silicic stage 3 magmas, which have high uniform initial 143 Nd/ 144 Nd ratios (ε Nd (T) = +9.3 + or -0.2) over a wide range of 147 Sm/ 144 Nd values (yielding a precise Early Permian Nd-isotope age of 278 ± 4 Ma (MSWD = 0.48)). Stage 3 magmas show pronounced subduction-related geochemical signatures similar to island arc tholeiites (IAT) from immature arcs. They are closely analogous to some (boninite)-IAT magmas which characterise 'infant arc' eruptive activity in forearc basins of present-day Western Pacific island arc systems. A wide variety of stage 3 magma compositions, ranging from near-primary basaltic dikes (Mg = 74) to extremely fractionated silicic plagiogranites with uniformly very depleted isotopic ratios, is consistent with slow spreading rates which gave rise to polybaric, closed-system fractionation of magmas and periodic chamber abandonment. Some stage 3 rocks with SiO 2 levels in the andesite range have low-TiO 2 contents and high Mg, and may be fractionated equivalents of boninites. High ε Nd (T) values of stage 3 magmas indicate a lack of subducted sediment with inherited crustal residence signatures, and reflect the extent of supra-subduction zone (SSZ) mantle wedge depletion. DMOB stage 3 magmas may represent foreac magmatism that was the precursor to normal subduction-related volcanism established by c. 265 Ma in the Brook Street Arc and derived

  16. High precision innovative micropump for artificial pancreas

    Science.gov (United States)

    Chappel, E.; Mefti, S.; Lettieri, G.-L.; Proennecke, S.; Conan, C.

    2014-03-01

    The concept of artificial pancreas, which comprises an insulin pump, a continuous glucose meter and a control algorithm, is a major step forward in managing patient with type 1 diabetes mellitus. The stability of the control algorithm is based on short-term precision micropump to deliver rapid-acting insulin and to specific integrated sensors able to monitor any failure leading to a loss of accuracy. Debiotech's MEMS micropump, based on the membrane pump principle, is made of a stack of 3 silicon wafers. The pumping chamber comprises a pillar check-valve at the inlet, a pumping membrane which is actuated against stop limiters by a piezo cantilever, an anti-free-flow outlet valve and a pressure sensor. The micropump inlet is tightly connected to the insulin reservoir while the outlet is in direct communication with the patient skin via a cannula. To meet the requirement of a pump dedicated to closed-loop application for diabetes care, in addition to the well-controlled displacement of the pumping membrane, the high precision of the micropump is based on specific actuation profiles that balance effect of pump elasticity in low-consumption push-pull mode.

  17. Sr-Pb-Nd isotopic evidence that both MORB and OIB sources contribute to oceanic island arc magmas in Fiji

    International Nuclear Information System (INIS)

    Gill, J.B.

    1984-01-01

    Twenty-eight new Pb, 20 Sr, and 9 Nd isotopic compositions are presented for 32 rocks and one galena from Fiji and the South Fiji (back-arc) Basin. The Fijian rocks range in age from 35 to 143 Nd/ 144 Nd and low 206 Pb/ 204 Pb). Nearly constant 207 Pb/ 204 Pb, and an OIB source component lying within the conventional Sr-Nd-Pb mantle array. In later calc-alkaline and shoshonitic series rocks, these same trace element and isotopic ratios are more like those of OIB. The change was not accompanied by an increase in 207 Pb/ 204 Pb or Cs/K, indeed, 207 Pb/ 204 Pb is closer to the mantle array in these later series. Consequently, the change indicates a greater contribution from OIB sources, rather than from recycled ocean crust. These interpretations require that both MORB and OIB sources coexist in the uppermost mantle above subducted lithosphere. (orig./WB)

  18. Sm-Nd isotope system of the Ukrainian shield (Korosten'sky massif) anorthosite-granite formation

    Energy Technology Data Exchange (ETDEWEB)

    Bogatikov, O A; Karpenko, S F; Sukhanov, M K; Spiridonov, V G

    1988-01-01

    The results of Sm-Nd isotope investigation of rocks of the Ukrainian shield anorthosite-granite association are described; this association, according to the geologic data, is the latest association in a seriesof self-contained anorthosited. The latters are connected with considerable masses of rapakiwi-granited. Isotope analysis is carried out by mass spectrometry. Isotope ratios /sup 147/Sm//sup 144/Nd and /sup 143/Nd//sup 144/Nd for five samples investigated are presented. Isotope data obtained are marked to be important information about the origin of rocks studied. Evident age difference of granite and basic components of the association is established, that idnores the possibility of the rock formation during crystallization differentiation. The basic value of the radiometric 1.89-1.74 milliared years age of the Ukrainian shield anorthosites lied in the fact that these data confirm once more the specific nature of the earth's crust evolution especially at early stages of its formation.

  19. High precision relative position sensing system for formation flying spacecraft

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop and test an optical sensing system that provides high precision relative position sensing for formation flying spacecraft.  A high precision...

  20. High Precision Edge Detection Algorithm for Mechanical Parts

    Directory of Open Access Journals (Sweden)

    Duan Zhenyun

    2018-04-01

    Full Text Available High precision and high efficiency measurement is becoming an imperative requirement for a lot of mechanical parts. So in this study, a subpixel-level edge detection algorithm based on the Gaussian integral model is proposed. For this purpose, the step edge normal section line Gaussian integral model of the backlight image is constructed, combined with the point spread function and the single step model. Then gray value of discrete points on the normal section line of pixel edge is calculated by surface interpolation, and the coordinate as well as gray information affected by noise is fitted in accordance with the Gaussian integral model. Therefore, a precise location of a subpixel edge was determined by searching the mean point. Finally, a gear tooth was measured by M&M3525 gear measurement center to verify the proposed algorithm. The theoretical analysis and experimental results show that the local edge fluctuation is reduced effectively by the proposed method in comparison with the existing subpixel edge detection algorithms. The subpixel edge location accuracy and computation speed are improved. And the maximum error of gear tooth profile total deviation is 1.9 μm compared with measurement result with gear measurement center. It indicates that the method has high reliability to meet the requirement of high precision measurement.

  1. High Precision Edge Detection Algorithm for Mechanical Parts

    Science.gov (United States)

    Duan, Zhenyun; Wang, Ning; Fu, Jingshun; Zhao, Wenhui; Duan, Boqiang; Zhao, Jungui

    2018-04-01

    High precision and high efficiency measurement is becoming an imperative requirement for a lot of mechanical parts. So in this study, a subpixel-level edge detection algorithm based on the Gaussian integral model is proposed. For this purpose, the step edge normal section line Gaussian integral model of the backlight image is constructed, combined with the point spread function and the single step model. Then gray value of discrete points on the normal section line of pixel edge is calculated by surface interpolation, and the coordinate as well as gray information affected by noise is fitted in accordance with the Gaussian integral model. Therefore, a precise location of a subpixel edge was determined by searching the mean point. Finally, a gear tooth was measured by M&M3525 gear measurement center to verify the proposed algorithm. The theoretical analysis and experimental results show that the local edge fluctuation is reduced effectively by the proposed method in comparison with the existing subpixel edge detection algorithms. The subpixel edge location accuracy and computation speed are improved. And the maximum error of gear tooth profile total deviation is 1.9 μm compared with measurement result with gear measurement center. It indicates that the method has high reliability to meet the requirement of high precision measurement.

  2. Plio-Pleistocene basanitic and melilititic series of the Bohemian Massif: K-Ar ages, major/trace element and Sr–Nd isotopic data

    Czech Academy of Sciences Publication Activity Database

    Ulrych, Jaromír; Ackerman, Lukáš; Balogh, K.; Hegner, E.; Jelínek, E.; Pécskay, Z.; Přichystal, A.; Upton, B. G. J.; Zimák, J.; Foltýnová, R.

    2013-01-01

    Roč. 73, č. 4 (2013), s. 429-450 ISSN 0009-2819 Institutional support: RVO:67985831 Keywords : Bohemian Massif * Plio-Pleistocene * Basanite * Melilitite * K-Ar age * Magmatism * Sr–Nd isotopes Subject RIV: DD - Geochemistry Impact factor: 1.397, year: 2013

  3. Nd isotopic structure of the Pacific Ocean 70-30 Ma and numerical evidence for vigorous ocean circulation and ocean heat transport in a greenhouse world

    Science.gov (United States)

    Thomas, Deborah J.; Korty, Robert; Huber, Matthew; Schubert, Jessica A.; Haines, Brian

    2014-05-01

    The oceanic meridional overturning circulation (MOC) is a crucial component of the climate system, impacting heat and nutrient transport, and global carbon cycling. Past greenhouse climate intervals present a paradox because their weak equator-to-pole temperature gradients imply a weaker MOC, yet increased poleward oceanic heat transport appears to be required to maintain these weak gradients. To investigate the mode of MOC that operated during the early Cenozoic, we compare new Nd isotope data with Nd tracer-enabled numerical ocean circulation and coupled climate model simulations. Assimilation of new Nd isotope data from South Pacific Deep Sea Drilling Project and Ocean Drilling Program Sites 323, 463, 596, 865, and 869 with previously published data confirm the hypothesized MOC characterized by vigorous sinking in the South and North Pacific 70 to 30 Ma. Compilation of all Pacific Nd isotope data indicates vigorous, distinct, and separate overturning circulations in each basin until 40 Ma. Simulations consistently reproduce South Pacific and North Pacific deep convection over a broad range of conditions, but cases using strong deep ocean vertical mixing produced the best data-model match. Strong mixing, potentially resulting from enhanced abyssal tidal dissipation, greater interaction of wind-driven internal wave activity with submarine plateaus, or higher than modern values of the geothermal heat flux enable models to achieve enhanced MOC circulation rates with resulting Nd isotope distributions consistent with the proxy data. The consequent poleward heat transport may resolve the paradox of warmer worlds with reduced temperature gradients.

  4. High-precision micro/nano-scale machining system

    Science.gov (United States)

    Kapoor, Shiv G.; Bourne, Keith Allen; DeVor, Richard E.

    2014-08-19

    A high precision micro/nanoscale machining system. A multi-axis movement machine provides relative movement along multiple axes between a workpiece and a tool holder. A cutting tool is disposed on a flexible cantilever held by the tool holder, the tool holder being movable to provide at least two of the axes to set the angle and distance of the cutting tool relative to the workpiece. A feedback control system uses measurement of deflection of the cantilever during cutting to maintain a desired cantilever deflection and hence a desired load on the cutting tool.

  5. Future high precision experiments and new physics beyond Standard Model

    International Nuclear Information System (INIS)

    Luo, Mingxing.

    1993-01-01

    High precision (< 1%) electroweak experiments that have been done or are likely to be done in this decade are examined on the basis of Standard Model (SM) predictions of fourteen weak neutral current observables and fifteen W and Z properties to the one-loop level, the implications of the corresponding experimental measurements to various types of possible new physics that enter at the tree or loop level were investigated. Certain experiments appear to have special promise as probes of the new physics considered here

  6. High-precision ground-based photometry of exoplanets

    Directory of Open Access Journals (Sweden)

    de Mooij Ernst J.W.

    2013-04-01

    Full Text Available High-precision photometry of transiting exoplanet systems has contributed significantly to our understanding of the properties of their atmospheres. The best targets are the bright exoplanet systems, for which the high number of photons allow very high signal-to-noise ratios. Most of the current instruments are not optimised for these high-precision measurements, either they have a large read-out overhead to reduce the readnoise and/or their field-of-view is limited, preventing simultaneous observations of both the target and a reference star. Recently we have proposed a new wide-field imager for the Observatoir de Mont-Megantic optimised for these bright systems (PI: Jayawardhana. The instruments has a dual beam design and a field-of-view of 17' by 17'. The cameras have a read-out time of 2 seconds, significantly reducing read-out overheads. Over the past years we have obtained significant experience with how to reach the high precision required for the characterisation of exoplanet atmospheres. Based on our experience we provide the following advice: Get the best calibrations possible. In the case of bad weather, characterise the instrument (e.g. non-linearity, dome flats, bias level, this is vital for better understanding of the science data. Observe the target for as long as possible, the out-of-transit baseline is as important as the transit/eclipse itself. A short baseline can lead to improperly corrected systematic and mis-estimation of the red-noise. Keep everything (e.g. position on detector, exposure time as stable as possible. Take care that the defocus is not too strong. For a large defocus, the contribution of the total flux from the sky-background in the aperture could well exceed that of the target, resulting in very strict requirements on the precision at which the background is measured.

  7. Hf-Nd Isotopes in West Philippine Basin Basalts: Results from International Ocean Discovery Program (IODP) Site U1438 and Implications for the Early History of the Izu-Bonin-Mariana (IBM) Subduction System

    Science.gov (United States)

    Yogodzinski, G. M.; Hocking, B.; Bizimis, M.; Hickey-Vargas, R.; Ishizuka, O.; Bogus, K.; Arculus, R. J.

    2015-12-01

    Drilling at IODP Site U1438, located immediately west of Kyushu-Palau Ridge (KPR), the site of IBM subduction initiation, penetrated 1460 m of volcaniclastic sedimentary rock and 150 m of underlying basement. Biostratigraphic controls indicate a probable age for the oldest sedimentary rocks at around 55 Ma (51-64 Ma - Arculus et al., Nat Geosci in-press). This is close to the 48-52 Ma time period of IBM subduction initiation, based on studies in the forearc. There, the first products of volcanism are tholeiitic basalts termed FAB (forearc basalt), which are more depleted than average MORB and show subtle indicators of subduction geochemical enrichment (Reagan et al., 2010 - Geochem Geophy Geosy). Shipboard data indicate that Site U1438 basement basalts share many characteristics with FABs, including primitive major elements (high MgO/FeO*) and strongly depleted incompatible element patterns (Ti, Zr, Ti/V and Zr/Y below those of average MORB). Initial results thus indicate that FAB geochemistry may have been produced not only in the forearc, but also in backarc locations (west of the KPR) at the time of subduction initiation. Hf-Nd isotopes for Site 1438 basement basalts show a significant range of compositions from ɛNd of 7.0 to 9.5 and ɛHf of 14.5 to 19.8 (present-day values). The data define a well-correlated and steep array in Hf-Nd isotope space. Relatively radiogenic Hf compared to Nd indicates an Indian Ocean-type MORB source, but the dominant signature, with ɛHf >16.5, is more radiogenic than most Indian MORB. The pattern through time is from more-to-less radiogenic and more variable Hf-Nd isotopes within the basement section. This pattern culminates in basaltic andesite sills, which intrude the lower parts of the sedimentary section. The sills have the least radiogenic compositions measured so far (ɛNd ~6.6, ɛHf ~13.8), and are similar to those of boninites of the IBM forearc and modern IBM arc and reararc rocks. The pattern within the basement

  8. High precision capacitive beam phase probe for KHIMA project

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji-Gwang, E-mail: windy206@hanmail.net [Korea Institute of Radiological and Medical Sciences, 215–4, Gongneung-dong, Nowon-t, Seoul 139–706 (Korea, Republic of); Yang, Tae-Keun [Korea Institute of Radiological and Medical Sciences, 215–4, Gongneung-dong, Nowon-t, Seoul 139–706 (Korea, Republic of); Forck, Peter [GSI Helmholtz Centre for Ion Research, Darmstadt 64291, German (Germany)

    2016-11-21

    In the medium energy beam transport (MEBT) line of KHIMA project, a high precision beam phase probe monitor is required for a precise tuning of RF phase and amplitude of Radio Frequency Quadrupole (RFQ) accelerator and IH-DTL linac. It is also used for measuring a kinetic energy of ion beam by time-of-flight (TOF) method using two phase probes. The capacitive beam phase probe has been developed. The electromagnetic design of the high precision phase probe was performed to satisfy the phase resolution of 1° (@200 MHz). It was confirmed by the test result using a wire test bench. The measured phase accuracy of the fabricated phase probe is 1.19 ps. The pre-amplifier electronics with the 0.125 ∼ 1.61 GHz broad-band was designed and fabricated for amplifying the signal strength. The results of RF frequency and beam energy measurement using a proton beam from the cyclotron in KIRAMS is presented.

  9. High precision pulsar timing and spin frequency second derivatives

    Science.gov (United States)

    Liu, X. J.; Bassa, C. G.; Stappers, B. W.

    2018-05-01

    We investigate the impact of intrinsic, kinematic and gravitational effects on high precision pulsar timing. We present an analytical derivation and a numerical computation of the impact of these effects on the first and second derivative of the pulsar spin frequency. In addition, in the presence of white noise, we derive an expression to determine the expected measurement uncertainty of a second derivative of the spin frequency for a given timing precision, observing cadence and timing baseline and find that it strongly depends on the latter (∝t-7/2). We show that for pulsars with significant proper motion, the spin frequency second derivative is dominated by a term dependent on the radial velocity of the pulsar. Considering the data sets from three Pulsar Timing Arrays, we find that for PSR J0437-4715 a detectable spin frequency second derivative will be present if the absolute value of the radial velocity exceeds 33 km s-1. Similarly, at the current timing precision and cadence, continued timing observations of PSR J1909-3744 for about another eleven years, will allow the measurement of its frequency second derivative and determine the radial velocity with an accuracy better than 14 km s-1. With the ever increasing timing precision and observing baselines, the impact of the, largely unknown, radial velocities of pulsars on high precision pulsar timing can not be neglected.

  10. The various correction methods to the high precision aeromagnetic data

    International Nuclear Information System (INIS)

    Xu Guocang; Zhu Lin; Ning Yuanli; Meng Xiangbao; Zhang Hongjian

    2014-01-01

    In the airborne geophysical survey, an outstanding achievement first depends on the measurement precision of the instrument, and the choice of measurement conditions, the reliability of data collection, followed by the correct method of measurement data processing, the rationality of the data interpretation. Obviously, geophysical data processing is an important task for the comprehensive interpretation of the measurement results, processing method is correct or not directly related to the quality of the final results. we have developed a set of personal computer software to aeromagnetic and radiometric survey data processing in the process of actual production and scientific research in recent years, and successfully applied to the production. The processing methods and flowcharts to the high precision aromagnetic data were simply introduced in this paper. However, the mathematical techniques of the various correction programes to IGRF and flying height and magnetic diurnal variation were stressily discussed in the paper. Their processing effectness were illustrated by taking an example as well. (authors)

  11. Cenozoic History of the Equatorial Indian Ocean Recorded by Nd Isotopes: The Closure of the Indonesian Gateway

    Science.gov (United States)

    Gourlan, A. T.; Meynadier, L.; Allegre, C. J.

    2005-12-01

    The northward tectonic motion of the Australian plate and the evolution of the Indonesian Island Arcs through the last 20 Ma, generate changes in the flow and the origin of the circulation between the Pacific and the Southern Indian Oceans. Indeed, the emergence of the Indonesian Archipelago and probably the rapid uplift of the island of Halmahera have dramatically reduced the Indonesian Gateway. However, the precise dating of this event is still a matter of debate. The Neodymium isotopic composition of marine sediments is an extremely good proxy to reconstruct the major changes in the past ocean circulation. The residence time of Nd is shorter than the circulation time of the global ocean. Therefore, the Nd isotopic composition varies between the different ocean basins and is function of changes in source provenances, paleocirculation, orogenic processes, and intensity of weathering on the continents as well as on the volcanic arcs. To reconstruct the evolution of the oceanic flow from the Pacific to the equatorial Indian Ocean since the Miocene, we have applied on high carbonates content sediments a leaching technique using acetic acid. The reliability of our technique has been assessed by comparison with the Hydroxylamine hydrochloride technique developed by Bayon et al (1). The Nd isotopic composition is determinated in the past seawater from the record in Fe-Mn oxides. The sedimentary sequences are accurately dated using bio and chimiostratigraphy. Three ODP Sites were chosen in the Indian Ocean with a water depth ranging from 1600 to 2800 m and mutually distant by about 3000 km. From West to East: Site 761 which is at the western edge of the Indonesian Gateway on the central northeastern part of the Wombat Plateau off NW Australia, Site 757 is located on the south of the Ninetyeast ridge and Site 707 is located in the western tropical Indian Ocean near the Seychelles Islands. Our data are compared with the first results from Site 807 located in the Pacific

  12. Mantle xenoliths from Nemby, Eastern Paraguay: O-Sr-Nd isotopes and trace elements of hosted clinopyroxenes

    International Nuclear Information System (INIS)

    Comin-Chiaramonti, P; Antonini, P; Girardi, V.A.V; Gomes, C.B; Laurora, S; Zanetti, A

    2001-01-01

    depleted compositions, both in LK and HK suites. It is believed that 'residual' pyroxenes incorporated REE during later metasomatic events (cf. Chen et al., 1989). The above observation is consistent with the Nd isotope ratios measured on clinopyroxenes, indicating a LREE-depleted source for some samples and supporting the hypothesis that clinopyroxenes from some lherzolites did not crystallize from an original LREE enriched component; other samples approach enriched or undifferentiated compositions. Alkaline basaltic magmas from deeper, garnetbearing mantle may be suitable enrichment agents (cf. Comin-Chiaramonti et al, 1997). Moreover, the Nemby xenoliths were probably involved in carbonatite metasomatism (Comin-Chiaramonti et al., 1991), as possibly indicated by the IE patterns of some clinopyroxenes. The latter are characterized by high LREE and Sr abundances coupled with depletion in Nb, Ti, Zr. Notably, similar behaviour has already been described for clinopyroxenes from peridotite xenoliths hosted in ocean island basalts from Samoa and Tubai, which, according to Hauri et 2 al. (1993), show clear evidence of carbonatitic metasomatism.This suggests a buffering dominated by olivine in the upper mantle, where the equilibration is supported by coherence between observed Oisotope fractionation and clinopyroxene temperatures. The observed radiogenic isotope trend (Bulk Earth vs Depleted Mantle) is not consistent with major element refractory parameters. A mixing between depleted and enriched components is suggested by isotope records both in clinopyroxenes and on a whole-rock scale (Fig. 3A). The enriched components were mostly trapped in some clinopyroxenes, which had previously crystallized from depleted to quasi-chondritic mantle sources. On the whole, the isotopic data seem to indicate that the lithospheric mantle prior to the enrichment event(s) was dominated by a depleted component, isotopically resembling MORB sources (cf. Song and Frey, 1989; Comin-Chiaramonti et

  13. High precision 3D coordinates location technology for pellet

    International Nuclear Information System (INIS)

    Fan Yong; Zhang Jiacheng; Zhou Jingbin; Tang Jun; Xiao Decheng; Wang Chuanke; Dong Jianjun

    2010-01-01

    In inertial confinement fusion (ICF) system, manual way has been used to collimate the pellet traditionally, which is time-consuming and low-level automated. A new method based on Binocular Vision is proposed, which can place the prospecting apparatus on the public diagnosis platform to reach relevant engineering target and uses the high precision two dimension calibration board. Iterative method is adopted to satisfy 0.1 pixel for corner extraction precision. Furthermore, SVD decomposition is used to remove the singularity corners and advanced Zhang's calibration method is applied to promote camera calibration precision. Experiments indicate that the RMS of three dimension coordinate measurement precision is 25 μm, and the max system RMS of distance measurement is better than 100 μm, satisfying the system index requirement. (authors)

  14. High-precision thermal and electrical characterization of thermoelectric modules

    Science.gov (United States)

    Kolodner, Paul

    2014-05-01

    This paper describes an apparatus for performing high-precision electrical and thermal characterization of thermoelectric modules (TEMs). The apparatus is calibrated for operation between 20 °C and 80 °C and is normally used for measurements of heat currents in the range 0-10 W. Precision thermometry based on miniature thermistor probes enables an absolute temperature accuracy of better than 0.010 °C. The use of vacuum isolation, thermal guarding, and radiation shielding, augmented by a careful accounting of stray heat leaks and uncertainties, allows the heat current through the TEM under test to be determined with a precision of a few mW. The fractional precision of all measured parameters is approximately 0.1%.

  15. Sr, Nd isotope geochemistry of volcanic rock series and its geological significance in the middle Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There exists extensive basic-acidic volcanic rock series in the middle section of the Okinawa Trough. Different types of these volcanic rocks have their own average strontium ratios of 0.704 749, 0.705 062, 0.708 771, 0.704 840 and 0.720 301 with average 143Nd/144Nd ratios of 0.512 820, 0.512 673, 0.512 413, 0.512 729 and 0.512 034. These ratios of Sr and Nd isotopes all fall on a theoretic hyperbolic curve of mixing between two end-members of MORB and rhyolitic magma. So we infer that these different kinds of volcanic rocks in the middle Okinawa Trough are the erupted product in different stages of formation and evolution of the trough crust. MORB magma, which had suffered assimilation, mixed with the early-formed crust-derived rhyolitic partial melt mass at different ratios; then, these mixed magma erupted and formed volcanic rock types of the trough. This study indicates that the Okinawa Trough is coming into a stage of submarine spreading from the stage of continental rift.

  16. Sr, Nd isotope geochemistry of volcanic rock series and its geological significance in the middle Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    孟宪伟; 陈志华; 杜德文; 吴金龙

    2000-01-01

    There exists extensive basic-acidic volcanic rock series in the middle section of the Okinawa Trough. Different types of these volcanic rocks have their own average strontium ratios of 0.704749, 0.705062, 0.708771, 0.704840 and 0.720301 with average 143Nd/144Nd ratios of 0.512 820, 0.512 673, 0.512 413, 0.512 729 and 0.512 034. These ratios of Sr and Nd isotopes all fall on a theoretic hyperbolic curve of mixing between two end-members of MORE and rhyolitic magma. So we infer that these different kinds of volcanic rocks in the middle Okinawa Trough are the erupted product in different stages of formation and evolution of the trough crust. MORE magma, which had suffered assimilation, mixed with the early-formed crust-derived rhyolitic partial melt mass at different ratios; then, these mixed magma erupted and formed volcanic rock types of the trough. This study indicates that the Okinawa Trough is coming into a stage of submarine spreading from the stage of continental rift.

  17. Sr-Nd isotopic characteristic, U-Pb zircon geochronology, and petrogenesis of Najmabad Granodiorite batholith, Eastern Iran

    Directory of Open Access Journals (Sweden)

    Mehrab Moradi

    2011-11-01

    Full Text Available The study area is located south of Ghonabad in Eastern Iran. This area is situated between two major faults, Darouneh to the north and Dashtbyaz to the south. The movements of these faults cased major dislocation of this block. Najmabad granodiorite to granite batholith is elongated trending east-west 2×8 Km2. Mineralization is associated with granite and monzonite. Alteration zones are: propylitic, sericitic, argillic and silicification. Chemically, granite-granodiorite is met-aluminous,, spider diagram normalized to lower continental crust show enrichment of LILE such as Rb, Cs, K and LREE (La, Ce , depletion of Ti, Sr, Ta, Nb, Ba, Cs. Based on low values of magnetic susceptibility [(5 to 11 × 10-5 SI], therefore it is classified as belonging to the ilmenite-series (reduced type. The result of U-Pb zircon age dating of granodiorite is 161.85 Ma (Middle Jurassic, Callovian time. Based on Initial εNd isotope values for granodiorite is -6.51, initial 87Sr/86Sr and 143Nd/144Nd ratios for granodiorite is (0.70913 and 0.512095, the magma for granite and granodiorite originated from the continental crust. During Middle Jurassic (Callovian due to continental collision, Upper Triassic to Lower Jurassic rocks is regionally metamorphosed. During the continental collision, Middle Jurassic (164-162Ma reduced type granitoid magma (Ilmenite series, continental crust melting formed and intruded these regional metamorphosed rock in Najmabad, Shah Kuh and Sorkh Kuh area.

  18. Sm-Nd in marine carbonates and phosphates: implications for Nd isotopes in seawater and crustal ages

    International Nuclear Information System (INIS)

    Shaw, H.F.; Wasserburg, G.J.

    1985-01-01

    This study explores the possibility of establishing Nd isotopic variations in seawater over geologic time. Calcite, aragonite and apatite are examined as possible phases recording seawater values of epsilonsubNd. Modern, biogenic and inorganically precipitated calcite and aragonite from marine environments were found to have Nd concentrations of from 0.2 to 70 ppb, showing that primary marine CaCO 3 contains little REE and that Nd/Ca is not greatly enhanced relative to seawater during carbonate precipitation. Very young marine limestone and dolomite containing no continental detritus have approx. 200 ppb Nd. All the carbonates are LREE enriched. Modern and very young Atlantic and Pacific carbonates have epsilonsub(Nd) in the range of shallow Atlantic and Pacific seawater respectively, implying that they derive their REE from local seawater. The Nd in well preserved carbonate fossils is 4 ppb, much greater than in their modern counterparts but like the high values found for carbonates in other studies. Results are also reported for apatite. They suggest that sedimentary apatite can be used to determine epsilonsub(Nd)(T) in ancient seawater. The seawater values so inferred range between -1.7 and -8.9 over the last 700 my and lie in the range of modern seawater, showing no evidence for drastic changes. (U.K.)

  19. Pb-Sr-Nd isotopic data of Indian Ocean ridges: New evidence of large-scale mapping of mantle heterogeneities

    International Nuclear Information System (INIS)

    Hamelin, B.; Dupre, B.; Allegre, C.J.

    1986-01-01

    A Pb-Sr-Nd isotope study of South West and East Indian Ridges confirms that the Indian Ocean belongs to a specific regional isotopic domain, as previously suggested by the results from islands of this ocean. The isotopic domain defined by the Indian MORB is indeed different from that of the North Atlantic and East Pacific Oceans. This demonstrates that the convective circulation of the upper mantle does not allow a rapid homogenization from one region to the other. The isotopic data of the Indian ridges can be interpreted by a contamination model, in which the depleted upper mantle (identical to that under the North Atlantic) is contaminated by two different types of contaminant, one corresponding to the source of the ''central Indian Ocean'' islands (Amsterdam, St. Paul, Marion, Prince Edward, Reunion, Rodriguez, Mauritius), and the other to a source similar to that of Walvis or Ninety East aseismic ridges. These two contaminants would have contributed to the ridge volcanism in different proportion over time. (orig.)

  20. Ash layer at ∼ 8 Ma in ODP site 758 from the Bay of Bengal: evidence from Sr, Nd isotopic compositions and rare earth elements

    International Nuclear Information System (INIS)

    Padmakumari, V.M.; Ahmad, S.M.

    2004-01-01

    Strontium and neodymium isotopic compositions are widely used to delineate the provenance of sedimentary formations. These isotopes have characteristic signatures for crust and mantle material and therefore can distinguish between volcanic and other rock types. 87 Sr/ 86 Sr. ε Nd (0) and rare earth elements REE of clay sediments from ODP site 758 in the Bay of Bengal is reported here. Our results clearly show that Sr and Nd isotopes can identify thin ash layers that otherwise may not easily be recognized

  1. High-precision gauging of metal rings

    Science.gov (United States)

    Carlin, Mats; Lillekjendlie, Bjorn

    1994-11-01

    Raufoss AS designs and produces air brake fittings for trucks and buses on the international market. One of the critical components in the fittings is a small, circular metal ring, which is going through 100% dimension control. This article describes a low-price, high accuracy solution developed at SINTEF Instrumentation based on image metrology and a subpixel resolution algorithm. The measurement system consists of a PC-plugg-in transputer video board, a CCD camera, telecentric optics and a machine vision strobe. We describe the measurement technique in some detail, as well as the robust statistical techniques found to be essential in the real life environment.

  2. Application of high precision temperature control technology in infrared testing

    Science.gov (United States)

    Cao, Haiyuan; Cheng, Yong; Zhu, Mengzhen; Chu, Hua; Li, Wei

    2017-11-01

    In allusion to the demand of infrared system test, the principle of Infrared target simulator and the function of the temperature control are presented. The key technology of High precision temperature control is discussed, which include temperature gathering, PID control and power drive. The design scheme of temperature gathering is put forward. In order to reduce the measure error, discontinuously current and four-wire connection for the platinum thermal resistance are adopted. A 24-bits AD chip is used to improve the acquisition precision. Fuzzy PID controller is designed because of the large time constant and continuous disturbance of the environment temperature, which result in little overshoot, rapid response, high steady-state accuracy. Double power operational amplifiers are used to drive the TEC. Experiments show that the key performances such as temperature control precision and response speed meet the requirements.

  3. High-precision positioning of radar scatterers

    NARCIS (Netherlands)

    Dheenathayalan, P.; Small, D.; Schubert, A.; Hanssen, R.F.

    2016-01-01

    Remote sensing radar satellites cover wide areas and provide spatially dense measurements, with millions of scatterers. Knowledge of the precise position of each radar scatterer is essential to identify the corresponding object and interpret the estimated deformation. The absolute position accuracy

  4. HIGH PRECISION COMPUTED TOMOGRAPHY FOR METROLOGY

    DEFF Research Database (Denmark)

    2017-01-01

    Disclosed is a CT system for performing measurements on an object. The CT system comprises a support element for supporting the object; a radiation source for radiating the object at a plurality of different angles; a radiation detector assembly for detecting radiation passed through the object a...

  5. High precision studies of directional correlations

    International Nuclear Information System (INIS)

    El-khosht, M.

    1980-01-01

    Two applications of the method of directional correlations are described. The first part deals with gamma-gamma directional correlations measurements. A total of 27 cascades have been studied in 97 Tc, 206 Pb and 206 Bi. Information is obtained on the angular momenta of levels, multipolarities of electromagnetic transitions and further, reduced transition probabilities. The later part of this thesis describes a determination of anisotropic directional correlation between gamma-rays and LX-rays in 160 Dy. To the authors' knowledge this is the first observation of an anisotropic correlation between gamma rays and X-rays following internal conversion. (Auth.)

  6. Characterisation of work function fluctuations for high-precision experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kahlenberg, Jan; Bickmann, Edward; Heil, Werner; Otten, Ernst W.; Schmidt, Christian; Wunderle, Alexander [Johannes Gutenberg-Universitaet Mainz (Germany); Babutzka, Martin; Schoenung, Kerstin [Karlsruher Institut fuer Technologie (Germany); Beck, Marcus [Johannes Gutenberg-Universitaet Mainz (Germany); Helmholtz-Institut Mainz (Germany)

    2016-07-01

    For a wide range of high-precision experiments in physics, well-defined electric potentials for achieving high measurement accuracies are required. An accurate determination of the electric potential is crucial for the measurement of the neutrino mass (KATRIN) as well as the measurement of the e{sup -} anti ν{sub e} correlation coefficient a in free neutron decay (aSPECT). Work function fluctuations on the electrodes lead to uncertainties in the distribution of the electric potential. For aSPECT, the electric potential has to be known at an accuracy of 10 mV. However, due to the patch effect of gold, work function fluctuations of several 100 meV can occur. Therefore, the work function distributions of the gold-plated electrodes have been measured using a Kelvin probe. Furthermore, the change of work function distributions over time as well as the influence of relative humidity on the work function measurement have been investigated. For aSPECT, the work function distributions of the gold-plated electrodes have been measured using a Kelvin probe. Due to the patch effect of gold, work function fluctuations of up to 160 meV occur. This would lead to a significant uncertainty of the potential barrier, which should be known at an accuracy of 10 mV. Furthermore, the change of work function distributions over time as well as the influence of relative humidity on the work function measurement have been investigated.

  7. High precision spectrophotometric analysis of thorium

    International Nuclear Information System (INIS)

    Palmieri, H.E.L.

    1984-01-01

    An accurate and precise determination of thorium is proposed. Precision of about 0,1% is required for the determination of macroquantities of thorium when processed. After an extensive literature search concerning this subject, spectrophotometric titration has been chosen, using dissodium ethylenediaminetetraacetate (EDTA) solution and alizarin-S as indicator. In order to obtain such a precision, an amount of 0,025 M EDTA solution precisely measured has been added and the titration was completed with less than 5 ml of 0,0025 M EDTA solution. It is usual to locate the end-point graphically, by plotting added titrant versus absorbance. The non-linear minimum square fit, using the Fletcher e Powell's minimization process and a computer programme. Besides the equivalence point, other parameters of titration were determined: the indicator concentration, the absorbance of the metal-indicator complex, and the stability constants of the metal-indicator and the metal-EDTA complexes. (Author) [pt

  8. Thorium spectrophotometric analysis with high precision

    International Nuclear Information System (INIS)

    Palmieri, H.E.L.

    1983-06-01

    An accurate and precise determination of thorium is proposed. Precision of about 0,1% is required for the determination of macroquantities of thorium processed. After an extensive literature search concerning this subject, spectrophotometric titration has been chosen, using disodium ethylenediaminetetraacetate (EDTA) solution and alizarin S as indicator. In order to obtain such a precision, an amount of 0,025 M EDTA solution precisely measured has been added and the titration was completed with less than 5 ml of 0,0025 M EDTA solution. It is usual to locate the end-point graphically, by plotting added titrant versus absorbance. The non-linear minimum square fit, using the Fletcher e Powell's minimization process and a computer program. (author)

  9. Design of a self-calibration high precision micro-angle deformation optical monitoring scheme

    Science.gov (United States)

    Gu, Yingying; Wang, Li; Guo, Shaogang; Wu, Yun; Liu, Da

    2018-03-01

    In order to meet the requirement of high precision and micro-angle measurement on orbit, a self-calibrated optical non-contact real-time monitoring device is designed. Within three meters, the micro-angle variable of target relative to measuring basis can be measured in real-time. The range of angle measurement is +/-50'', the angle measurement accuracy is less than 2''. The equipment can realize high precision real-time monitoring the micro-angle deformation, which caused by high strength vibration and shock of rock launching, sun radiation and heat conduction on orbit and so on.

  10. Nd-isotopes in selected mantle-derived rocks and minerals and their implications for mantle evolution

    Science.gov (United States)

    Basu, A.R.; Tatsumoto, M.

    1980-01-01

    The Sm-Nd systematics in a variety of mantle-derived samples including kimberlites, alnoite, carbonatite, pyroxene and amphibole inclusions in alkali basalts and xenolithic eclogites, granulites and a pyroxene megacryst in kimberlites are reported. The additional data on kimberlites strengthen our earlier conclusion that kimberlites are derived from a relatively undifferentiated chondritic mantle source. This conclusion is based on the observation that the e{open}Nd values of most of the kimberlites are near zero. In contrast with the kimberlites, their garnet lherzolite inclusions show both time-averaged Nd enrichment and depletion with respect to Sm. Separated clinopyroxenes in eclogite xenoliths from the Roberts Victor kimberlite pipe show both positive and negative e{open}Nd values suggesting different genetic history. A whole rock lower crustal scapolite granulite xenolith from the Matsoku kimberlite pipe shows a negative e{open}Nd value of -4.2, possibly representative of the base of the crust in Lesotho. It appears that all inclusions, mafic and ultramafic, in kimberlites are unrelated to their kimberlite host. The above data and additional Sm-Nd data on xenoliths in alkali basalts, alpine peridotite and alnoite-carbonatites are used to construct a model for the upper 200 km of the earth's mantle - both oceanic and continental. The essential feature of this model is the increasing degree of fertility of the mantle with depth. The kimberlite's source at depths below 200 km in the subcontinental mantle is the most primitive in this model, and this primitive layer is also extended to the suboceanic mantle. However, it is clear from the Nd-isotopic data in the xenoliths of the continental kimberlites that above 200 km the continental mantle is distinctly different from their suboceanic counterpart. ?? 1980 Springer-Verlag.

  11. High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera Tracking

    Science.gov (United States)

    Liss, J.; Dunagan, S. E.; Johnson, R. R.; Chang, C. S.; LeBlanc, S. E.; Shinozuka, Y.; Redemann, J.; Flynn, C. J.; Segal-Rosenhaimer, M.; Pistone, K.; Kacenelenbogen, M. S.; Fahey, L.

    2016-12-01

    High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera TrackingThe NASA Ames Sun-photometer-Satellite Group, DOE, PNNL Atmospheric Sciences and Global Change Division, and NASA Goddard's AERONET (AErosol RObotic NETwork) team recently collaborated on the development of a new airborne sunphotometry instrument that provides information on gases and aerosols extending far beyond what can be derived from discrete-channel direct-beam measurements, while preserving or enhancing many of the desirable AATS features (e.g., compactness, versatility, automation, reliability). The enhanced instrument combines the sun-tracking ability of the current 14-Channel NASA Ames AATS-14 with the sky-scanning ability of the ground-based AERONET Sun/sky photometers, while extending both AATS-14 and AERONET capabilities by providing full spectral information from the UV (350 nm) to the SWIR (1,700 nm). Strengths of this measurement approach include many more wavelengths (isolated from gas absorption features) that may be used to characterize aerosols and detailed (oversampled) measurements of the absorption features of specific gas constituents. The Sky Scanning Sun Tracking Airborne Radiometer (3STAR) replicates the radiometer functionality of the AATS-14 instrument but incorporates modern COTS technologies for all instruments subsystems. A 19-channel radiometer bundle design is borrowed from a commercial water column radiance instrument manufactured by Biospherical Instruments of San Diego California (ref, Morrow and Hooker)) and developed using NASA funds under the Small Business Innovative Research (SBIR) program. The 3STAR design also incorporates the latest in robotic motor technology embodied in Rotary actuators from Oriental motor Corp. having better than 15 arc seconds of positioning accuracy. Control system was designed, tested and simulated using a Hybrid-Dynamical modeling methodology. The design also replaces the classic quadrant detector tracking sensor with a

  12. High precision absolute differential cross-section measurements for proton-proton elastic scattering at 491.9, 575.5, 641.6, 728.2, and 793.0 MeV

    International Nuclear Information System (INIS)

    Simon, A.J.

    1993-07-01

    The proton-proton absolute elastic differential cross section, σ pp (θ), has been measured at incident proton beam energies of 491.9, 575.5, 641.6, 728.2, and 793.0 MeV at laboratory scattering angles of ∼15 degree to ∼42 degree with a total uncertainty on the order of 1%. The measurements were made at the Clinton P. Anderson Los Alamos Meson Physics Facility (LAMPF) and employed a new beam counting technique which provided a better overall beam normalization compared to previous experiments of this type. The cross section was measured with CH 2 targets and a primary liquid, LH 2 , target to determine the uncertainties in some systematic corrections. Extreme care was taken to reduce individual systematic errors to less than 0.5%

  13. A new set-up for simultaneous high-precision measurements of CO2, δ13C-CO2 and δ18O-CO2 on small ice core samples

    Science.gov (United States)

    Jenk, Theo Manuel; Rubino, Mauro; Etheridge, David; Ciobanu, Viorela Gabriela; Blunier, Thomas

    2016-08-01

    Palaeoatmospheric records of carbon dioxide and its stable carbon isotope composition (δ13C) obtained from polar ice cores provide important constraints on the natural variability of the carbon cycle. However, the measurements are both analytically challenging and time-consuming; thus only data exist from a limited number of sampling sites and time periods. Additional analytical resources with high analytical precision and throughput are thus desirable to extend the existing datasets. Moreover, consistent measurements derived by independent laboratories and a variety of analytical systems help to further increase confidence in the global CO2 palaeo-reconstructions. Here, we describe our new set-up for simultaneous measurements of atmospheric CO2 mixing ratios and atmospheric δ13C and δ18O-CO2 in air extracted from ice core samples. The centrepiece of the system is a newly designed needle cracker for the mechanical release of air entrapped in ice core samples of 8-13 g operated at -45 °C. The small sample size allows for high resolution and replicate sampling schemes. In our method, CO2 is cryogenically and chromatographically separated from the bulk air and its isotopic composition subsequently determined by continuous flow isotope ratio mass spectrometry (IRMS). In combination with thermal conductivity measurement of the bulk air, the CO2 mixing ratio is calculated. The analytical precision determined from standard air sample measurements over ice is ±1.9 ppm for CO2 and ±0.09 ‰ for δ13C. In a laboratory intercomparison study with CSIRO (Aspendale, Australia), good agreement between CO2 and δ13C results is found for Law Dome ice core samples. Replicate analysis of these samples resulted in a pooled standard deviation of 2.0 ppm for CO2 and 0.11 ‰ for δ13C. These numbers are good, though they are rather conservative estimates of the overall analytical precision achieved for single ice sample measurements. Facilitated by the small sample requirement

  14. Geology, mineralization, U-Pb dating and Sr-Nd isotope geochemistry of intrusive bodies in northeast of Kashmar

    Directory of Open Access Journals (Sweden)

    Alireza Almasi

    2015-04-01

    Full Text Available Alireza Almasi1, Mohammad Hassan Karimpour1*, Khosrow Ebrahimi Nasrabadi1, Behnam Rahimi1, Urs KlÖtzli2 and Jose Francisco Santos3 Introduction The study area is located in central part of the Khaf- Kashmar-Bardeskan belt which is volcano-plutonic belt at the north of the Dorouneh fault in the north of Lut block. The north of the Lut block is affected by tectonic rotation and subduction processes which occur in the east of Iran (Tirrul et al., 1983. The magmatism of Lut block begins in Jurassic and continues in Tertiary (Aghanabati, 1995. Karimpour (Karimpour, 2006 pointed out the Khaf-Kashmar-Bardeskan belt has significant potential for IOCG type mineralization such as Kuh-e-Zar, Tannurjeh, and Sangan (Karimpour, 2006; Mazloumi, 2009. The data gathered on the I-type intrusive rocks include their field geology, petrography, U–Pb zircon dating and Sr–Nd isotope and also alteration and mineralization in the study area. Materials and methods - Preparation of 150 thin sections of rock samples for study of petrography and alteration of the intrusive rocks. - Magnetic susceptibility measuring of intrusive rocks. - U-Pb dating in zircon of I-type intrusive rocks by Laser-Ablation Multi Collector ICP-MS method. - Sr-Nd analysis on 5 samples of I-type intrusive rocks by Multi-Collector Thermal Ionization Mass Spectrometer (TIMS VG Sector 54 instrument. - Mineralography and paragenetic studies of ore-bearing quartz veins and geochemical analysis for 28 samples. - Production of the geology, alteration and mineralization maps by scale: 1:20000 in GIS. Results Oblique subduction in southern America initiated an arc-parallel fault and shear zones in the back of continental magmatic arc (Sillitoe, 2003. Because of this event, pull-apart basins were formed and high-K to shoshonitic calc-alkalineI- and A-type magmatism occur (Sillitoe, 2003. Most important deposits accompany with this magmatism are Au-Cu deposits types and Fe-Skarns (Sillitoe, 2003. We have

  15. Consequences of shoaling of the Central American Seaway determined from modeling Nd isotopes

    Science.gov (United States)

    Sepulchre, P.; Arsouze, T.; Donnadieu, Y.; Dutay, J.-C.; Jaramillo, C.; Le Bras, J.; Martin, E.; Montes, C.; Waite, A. J.

    2014-03-01

    The Central American Seaway played a pivotal role in shaping global climate throughout the late Cenozoic. Recent geological surveys have provided new constraints on timing of the seaway shoaling, while neodymium isotopic (ɛNd) data measured on fossil teeth, debris, and ferromanganese crusts have helped define the history of water masses in the region. Here we provide the first 3-D simulations of ɛNd responses to the shoaling seaway. Our model suggests that a narrow and shallow seaway is sufficient to affect interoceanic circulation, that inflow/outflow balance between the Caribbean and the Antilles responds nonlinearly to sill depth, and that a seaway narrower than 400 km is consistent with an active Atlantic meridional overturning circulation during the late Miocene. Simulated ɛNd values in the Caribbean confirm that inputs from radiogenic Pacific waters in the Caribbean decrease as the seaway shoals. Despite model limitations, a comparison between our results and ɛNd values recorded in the Caribbean helps constrain the depth of the Central American Seaway through time, and we infer that a depth between 50 and 200 m could have been reached 10 Ma ago.

  16. High precision refractometry based on Fresnel diffraction from phase plates.

    Science.gov (United States)

    Tavassoly, M Taghi; Naraghi, Roxana Rezvani; Nahal, Arashmid; Hassani, Khosrow

    2012-05-01

    When a transparent plane-parallel plate is illuminated at a boundary region by a monochromatic parallel beam of light, Fresnel diffraction occurs because of the abrupt change in phase imposed by the finite change in refractive index at the plate boundary. The visibility of the diffraction fringes varies periodically with changes in incident angle. The visibility period depends on the plate thickness and the refractive indices of the plate and the surrounding medium. Plotting the phase change versus incident angle or counting the visibility repetition in an incident-angle interval provides, for a given plate thickness, the refractive index of the plate very accurately. It is shown here that the refractive index of a plate can be determined without knowing the plate thickness. Therefore, the technique can be utilized for measuring plate thickness with high precision. In addition, by installing a plate with known refractive index in a rectangular cell filled with a liquid and following the described procedures, the refractive index of the liquid is obtained. The technique is applied to measure the refractive indices of a glass slide, distilled water, and ethanol. The potential and merits of the technique are also discussed.

  17. High-Precision Direct Mass Determination of Unstable Isotopes

    CERN Multimedia

    2002-01-01

    The extension of systematic high-precision measurements of the nuclear mass to nuclei far from the valley of $\\beta$ stability is of great interest in nuclear physics and astrophysics. The mass, or binding energy, is a fundamental gross property and a key input parameter for nuclear matter calculations. It is also a sensitive probe for collective and single-particle effects in nuclear structure. \\\\ \\\\ For such purposes, nuclear masses need to be known to an accuracy of about 10$^{-7}$ (i.e. $\\Delta$M~$\\leq$~10~keV for A~=~100). To resolve a particular mass from its nuclear isomers and isobars, resolving power of 10$^6$ are often required. To achieve this, the ions delivered by the on-line mass separator ISOLDE are confined in a Penning quadrupole trap. This trap is placed in the very homogeneous and stable magnetic field of a superconducting magnet. Here, the cyclotron frequency and hence the mass are determined. \\\\ \\\\ The first measurements using this new technique have been completed for a long chain of Cs ...

  18. HIGH PRECISION ROVIBRATIONAL SPECTROSCOPY OF OH{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Markus, Charles R.; Hodges, James N.; Perry, Adam J.; Kocheril, G. Stephen; McCall, Benjamin J. [Department of Chemistry, University of Illinois, Urbana, IL 61801 (United States); Müller, Holger S. P., E-mail: bjmccall@illinois.edu [I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln (Germany)

    2016-02-01

    The molecular ion OH{sup +} has long been known to be an important component of the interstellar medium. Its relative abundance can be used to indirectly measure cosmic ray ionization rates of hydrogen, and it is the first intermediate in the interstellar formation of water. To date, only a limited number of pure rotational transitions have been observed in the laboratory making it necessary to indirectly calculate rotational levels from high-precision rovibrational spectroscopy. We have remeasured 30 transitions in the fundamental band with MHz-level precision, in order to enable the prediction of a THz spectrum of OH{sup +}. The ions were produced in a water cooled discharge of O{sub 2}, H{sub 2}, and He, and the rovibrational transitions were measured with the technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy. These values have been included in a global fit of field free data to a {sup 3}Σ{sup −} linear molecule effective Hamiltonian to determine improved spectroscopic parameters which were used to predict the pure rotational transition frequencies.

  19. Measurement of N2O and CH4 soil fluxes from garden, agricultural and natural soils using both closed and open chamber systems coupled with high-precision CRDS analyzer

    Science.gov (United States)

    He, Yonggang; Jacobson, Gloria; Alexander, Chris; Fleck, Derek; Hoffnagel, John; Del Campo, Bernardo; Rella, Chris

    2013-04-01

    Studying the emission and uptake of greenhouse gases from soil is essential for understanding, adapting to and ultimately mitigating the effects of climate change. To-date, majority of such studies have been focused on carbon dioxide (CO2 ) , however, in 2006 the EPA estimated that "Agricultural activities currently generate the largest share, 63 percent, of the world's anthropogenic non-carbon dioxide (non-CO2) emissions (84 percent of nitrous oxide [N2O] and 52 percent of methane[CH4]), and make up roughly 15 percent of all anthropogenic greenhouse gas emissions" (Prentice et al., 2001). Therefore, enabling accurate N2O and CH4 flux measurements in the field are clearly critical to our ability to better constrain carbon and nitrogen budgets, characterize soil sensitivities, agricultural practices, and microbial processes like denitrification and nitrification. To aide in these studies, Picarro has developed a new analyzer based on its proven, NIR technology platform, which is capable of measuring both N2O and CH4 down to ppb levels in a single, field-deployable analyzer. This analyzer measures N2O with a 1-sigma, precision of 3.5 ppb and CH4 with a 1-sigma precision of 3ppb on a 5 minute average. The instrument also has extremely low drift to enable accurate measurements with infrequent calibrations. The data rate of the analyzer is on the order of 5 seconds in order to capture fast, episodic emission events. One of the keys to making accurate CRDS measurements is to thoroughly characterize and correct for spectral interfering species. This is especially important for closed system soil chambers used on agricultural soils where a variety of soil amendments may be applied and gases not usually present in ambient air could concentrate to high levels. In this work, we present the results of analyzer interference testing and corrections completed for the interference of carbon dioxide, methane, ammonia, ethane, ethylene, acetylene, and water on N2O. In addition, we

  20. Electromagnetic Charge Radius of the Pion at High Precision

    Science.gov (United States)

    Ananthanarayan, B.; Caprini, Irinel; Das, Diganta

    2017-09-01

    We present a determination of the pion charge radius from high precision data on the pion vector form factor from both timelike and spacelike regions, using a novel formalism based on analyticity and unitarity. At low energies, instead of the poorly known modulus of the form factor, we use its phase, known with high accuracy from Roy equations for π π elastic scattering via the Fermi-Watson theorem. We use also the values of the modulus at several higher timelike energies, where the data from e+e- annihilation and τ decay are mutually consistent, as well as the most recent measurements at spacelike momenta. The experimental uncertainties are implemented by Monte Carlo simulations. The results, which do not rely on a specific parametrization, are optimal for the given input information and do not depend on the unknown phase of the form factor above the first inelastic threshold. Our prediction for the charge radius of the pion is rπ=(0.657 ±0.003 ) fm , which amounts to an increase in precision by a factor of about 2.7 compared to the Particle Data Group average.

  1. High precision isotopic ratio analysis of volatile metal chelates

    International Nuclear Information System (INIS)

    Hachey, D.L.; Blais, J.C.; Klein, P.D.

    1980-01-01

    High precision isotope ratio measurements have been made for a series of volatile alkaline earth and transition metal chelates using conventional GC/MS instrumentation. Electron ionization was used for alkaline earth chelates, whereas isobutane chemical ionization was used for transition metal studies. Natural isotopic abundances were determined for a series of Mg, Ca, Cr, Fe, Ni, Cu, Cd, and Zn chelates. Absolute accuracy ranged between 0.01 and 1.19 at. %. Absolute precision ranged between +-0.01-0.27 at. % (RSD +- 0.07-10.26%) for elements that contained as many as eight natural isotopes. Calibration curves were prepared using natural abundance metals and their enriched 50 Cr, 60 Ni, and 65 Cu isotopes covering the range 0.1-1010.7 at. % excess. A separate multiple isotope calibration curve was similarly prepared using enriched 60 Ni (0.02-2.15 at. % excess) and 62 Ni (0.23-18.5 at. % excess). The samples were analyzed by GC/CI/MS. Human plasma, containing enriched 26 Mg and 44 Ca, was analyzed by EI/MS. 1 figure, 5 tables

  2. Modelling Nd-isotopes with a coarse resolution ocean circulation model: Sensitivities to model parameters and source/sink distributions

    International Nuclear Information System (INIS)

    Rempfer, Johannes; Stocker, Thomas F.; Joos, Fortunat; Dutay, Jean-Claude; Siddall, Mark

    2011-01-01

    The neodymium (Nd) isotopic composition (Nd) of seawater is a quasi-conservative tracer of water mass mixing and is assumed to hold great potential for paleo-oceanographic studies. Here we present a comprehensive approach for the simulation of the two neodymium isotopes 143 Nd, and 144 Nd using the Bern3D model, a low resolution ocean model. The high computational efficiency of the Bern3D model in conjunction with our comprehensive approach allows us to systematically and extensively explore the sensitivity of Nd concentrations and ε Nd to the parametrisation of sources and sinks. Previous studies have been restricted in doing so either by the chosen approach or by computational costs. Our study thus presents the most comprehensive survey of the marine Nd cycle to date. Our model simulates both Nd concentrations as well as ε Nd in good agreement with observations. ε Nd co-varies with salinity, thus underlining its potential as a water mass proxy. Results confirm that the continental margins are required as a Nd source to simulate Nd concentrations and ε Nd consistent with observations. We estimate this source to be slightly smaller than reported in previous studies and find that above a certain magnitude its magnitude affects ε Nd only to a small extent. On the other hand, the parametrisation of the reversible scavenging considerably affects the ability of the model to simulate both, Nd concentrations and ε Nd . Furthermore, despite their small contribution, we find dust and rivers to be important components of the Nd cycle. In additional experiments, we systematically varied the diapycnal diffusivity as well as the Atlantic-to-Pacific freshwater flux to explore the sensitivity of Nd concentrations and its isotopic signature to the strength and geometry of the overturning circulation. These experiments reveal that Nd concentrations and ε Nd are comparatively little affected by variations in diapycnal diffusivity and the Atlantic-to-Pacific freshwater flux

  3. Deep circulation changes in the South Atlantic since the Last Glacial Maximum from Nd isotope and multi-proxy records

    Science.gov (United States)

    Wei, R.; Abouchami, W.; Zahn, R.; Masque, P.

    2016-01-01

    We report down-core sedimentary Nd isotope (εNd) records from two South Atlantic sediment cores, MD02-2594 and GeoB3603-2, located on the western South African continental margin. The core sites are positioned downstream of the present-day flow path of North Atlantic Deep Water (NADW) and close to the Southern Ocean, which makes them suitable for reconstructing past variability in NADW circulation over the last glacial cycle. The Fe-Mn leachates εNd records show a coherent decreasing trend from glacial radiogenic values towards less radiogenic values during the Holocene. This trend is confirmed by εNd in fish debris and mixed planktonic foraminifera, albeit with an offset during the Holocene to lower values relative to the leachates, matching the present-day composition of NADW in the Cape Basin. We interpret the εNd changes as reflecting the glacial shoaling of Southern Ocean waters to shallower depths combined with the admixing of southward flowing Northern Component Water (NCW). A compilation of Atlantic εNd records reveals increasing radiogenic isotope signatures towards the south and with increasing depth. This signal is most prominent during the Last Glacial Maximum (LGM) and of similar amplitude across the Atlantic basin, suggesting continuous deep water production in the North Atlantic and export to the South Atlantic and the Southern Ocean. The amplitude of the εNd change from the LGM to Holocene is largest in the southernmost cores, implying a greater sensitivity to the deglacial strengthening of NADW at these sites. This signal impacted most prominently the South Atlantic deep and bottom water layers that were particularly deprived of NCW during the LGM. The εNd variations correlate with changes in 231Pa/230Th ratios and benthic δ13C across the deglacial transition. Together with the contrasting 231Pa/230Th: εNd pattern of the North and South Atlantic, this indicates a progressive reorganization of the AMOC to full strength during the Holocene.

  4. High-Precision Registration of Point Clouds Based on Sphere Feature Constraints

    Directory of Open Access Journals (Sweden)

    Junhui Huang

    2016-12-01

    Full Text Available Point cloud registration is a key process in multi-view 3D measurements. Its precision affects the measurement precision directly. However, in the case of the point clouds with non-overlapping areas or curvature invariant surface, it is difficult to achieve a high precision. A high precision registration method based on sphere feature constraint is presented to overcome the difficulty in the paper. Some known sphere features with constraints are used to construct virtual overlapping areas. The virtual overlapping areas provide more accurate corresponding point pairs and reduce the influence of noise. Then the transformation parameters between the registered point clouds are solved by an optimization method with weight function. In that case, the impact of large noise in point clouds can be reduced and a high precision registration is achieved. Simulation and experiments validate the proposed method.

  5. Changing styles of crustal growth in Southern Africa: constraints from geochemical and Sr-Nd isotope studies in Archaean to Pan African terrains

    International Nuclear Information System (INIS)

    McDermott, F.; Hawkesworth, C.J.; Harris, N.B.W.

    1988-01-01

    Nd isotopic data was presented for southern Africa in support of episodic crustal growth. Over 50 percent of the continental crust there had formed before 2.5 Ga, and less than 10 percent was produced after about 1.0 Ga. The data imply a mean crustal age of about 2.4 Ga for southern Africa, and a higher rate of crustal growth than that derived from Australian shale data, particularly during the Proterozoic. Isotopic data from Damara metasediments imply that there is no need to invoke decoupling of the Rb-Sr and Sm-Nd systems in the continental crust

  6. Pb, Sr, and Nd isotopic compositions of a suite of Large Archean, igneous rocks, eastern Beartooth Mountains - Implications for crust-mantle evolution

    Science.gov (United States)

    Wooden, J. L.; Mueller, P. A.

    1988-01-01

    Compositionally diverse Late Archean rocks (2.74-2.79 Ga old) from the eastern Beartooth Mountains (Montana and Wyoming) were studied and shown to have the same initial Pb, Sr, and Nd isotopic ratios. Lead and Sr initial ratios are higher and Nd initial values lower than predicted for rocks derived from model mantle sources and strongly indicate the involvement of an older crustal reservoir in the genesis of these rocks. A model involving subduction of continental detritus and contamination of the overlying mantle is suggested.

  7. Clay minerals and Sr-Nd isotopes of the sediments along the western margin of India and their implication for sediment provenance

    Digital Repository Service at National Institute of Oceanography (India)

    Kessarkar, P.M.; Rao, V.P.; Ahmad, S; Babu, G.A.

    - gion is occupied by Recent alluvium and the Warkala beds (ferruginised sand stones with inter- calated clays) of Tertiary age. Extensive laterisation of the parent rocks is a characteristic feature in western India. Bauxite- and laterite...^Nd isotopes of the sediments along the western margin of India and their implication for sediment provenance Pratima M. Kessarkar a , V. Purnachandra Rao a;C3 , S.M. Ahmad b , G. Anil Babu b a National Institute of Oceanography, Dona Paula, Goa 403 004, India...

  8. Changing styles of crustal growth in Southern Africa: Constraints from geochemical and Sr-Nd isotope studies in Archaean to Pan African terrains

    Science.gov (United States)

    Mcdermott, F.; Hawkesworth, C. J.; Harris, N. B. W.

    1988-01-01

    Nd isotopic data was presented for southern Africa in support of episodic crustal growth. Over 50 percent of the continental crust there had formed before 2.5 Ga, and less than 10 percent was produced after about 1.0 Ga. The data imply a mean crustal age of about 2.4 Ga for southern Africa, and a higher rate of crustal growth than that derived from Australian shale data, particularly during the Proterozoic. Isotopic data from Damara metasediments imply that there is no need to invoke decoupling of the Rb-Sr and Sm-Nd systems in the continental crust.

  9. Research on the high-precision non-contact optical detection technology for banknotes

    Science.gov (United States)

    Jin, Xiaofeng; Liang, Tiancai; Luo, Pengfeng; Sun, Jianfeng

    2015-09-01

    The technology of high-precision laser interferometry was introduced for optical measurement of the banknotes in this paper. Taking advantage of laser short wavelength and high sensitivity, information of adhesive tape and cavity about the banknotes could be checked efficiently. Compared with current measurement devices, including mechanical wheel measurement device, Infrared measurement device, ultrasonic measurement device, the laser interferometry measurement has higher precision and reliability. This will improve the ability of banknotes feature information in financial electronic equipment.

  10. High-precision performance testing of the LHC power converters

    CERN Document Server

    Bastos, M; Dreesen, P; Fernqvist, G; Fournier, O; Hudson, G

    2007-01-01

    The magnet power converters for LHC were procured in three parts, power part, current transducers and control electronics, to enable a maximum of industrial participation in the manufacturing and still guarantee the very high precision (a few parts in 10-6) required by LHC. One consequence of this approach was several stages of system tests: factory reception tests, CERN reception tests, integration tests , short-circuit tests and commissioning on the final load in the LHC tunnel. The majority of the power converters for LHC have now been delivered, integrated into complete converter and high-precision performance testing is well advanced. This paper presents the techniques used for high-precision testing and the results obtained.

  11. What can we learn from high precision measurements of neutrino ...

    Indian Academy of Sciences (India)

    To see how a µ ↔ τ symmetry of the neutrino mass matrix appears in the mixing matrix, let us consider the case of ... whether one can have mass matrices invariant under νµ ↔ ντ symmetry while giving ∆m2. ®. = 0 and θ12 ..... symmetry that unifies quarks and leptons, which includes the SU(4)-color group of Pati and Salam.

  12. Mantle heterogeneity in northeastern Africa: evidence from Nd isotopic compositions and hygromagmaphile element geochemistry of basaltic rocks from the Gulf of Tadjoura and southern Red Sea regions

    International Nuclear Information System (INIS)

    Barrat, J.A.; Jahn, B.M.; Auvray, B.; Hamdi, H.; Joron, J.L.

    1990-01-01

    Basaltic rocks from the Gulf of Tadjoura and southern Red Sea regions have been analysed for their Nd isotopic compositions and major and trace element concentrations. The wide variation in isotopic and geochemical compositions of the basaltic rocks is best explained by the mixing phenomenon involving a variety of mantle source components. To test the mixing hypothesis, a combined use of Nd isotopes and hygromagmaphile elemental ratios is proven very powerful. Three reservoirs have been identified as minimum components in their petrogenesis: (1) DMM (depleted MORB mantle), a mantle source depleted in light rare earth elements (LREE), which is the principal component of the N-MORB type basalts of this region; (2) REC (Ramad enriched component), equivalent to the hot-spot type of source detected in the south of Red Sea; (3) TEC (Tadjoura enriched component), a rather unique component located in the region of Tadjoura Gulf; it is characterised by a relative depletion in Rb, K, Th and U in a primitive mantle- or chondrite-normalised incompatible element pattern; this component could have been produced by mantle metasomatism of an originally depleted mantle. Mixing in various proportions of the above components is considered to be the principal mechanism for the formation of basalts with such diverse isotopic and trace element compositions. (orig.)

  13. Properties of the proton therapy. A high precision radiotherapy

    International Nuclear Information System (INIS)

    Anon.

    2005-01-01

    The proton therapy is a radiotherapy using protons beams. The protons present interesting characteristics but they need heavy technologies to be used, such particles accelerators, radiation protection wall and sophisticated technologies to reach the high precision allowed by their ballistic qualities (planning of treatment, beam conformation and patient positioning). (N.C.)

  14. Layered compression for high-precision depth data.

    Science.gov (United States)

    Miao, Dan; Fu, Jingjing; Lu, Yan; Li, Shipeng; Chen, Chang Wen

    2015-12-01

    With the development of depth data acquisition technologies, access to high-precision depth with more than 8-b depths has become much easier and determining how to efficiently represent and compress high-precision depth is essential for practical depth storage and transmission systems. In this paper, we propose a layered high-precision depth compression framework based on an 8-b image/video encoder to achieve efficient compression with low complexity. Within this framework, considering the characteristics of the high-precision depth, a depth map is partitioned into two layers: 1) the most significant bits (MSBs) layer and 2) the least significant bits (LSBs) layer. The MSBs layer provides rough depth value distribution, while the LSBs layer records the details of the depth value variation. For the MSBs layer, an error-controllable pixel domain encoding scheme is proposed to exploit the data correlation of the general depth information with sharp edges and to guarantee the data format of LSBs layer is 8 b after taking the quantization error from MSBs layer. For the LSBs layer, standard 8-b image/video codec is leveraged to perform the compression. The experimental results demonstrate that the proposed coding scheme can achieve real-time depth compression with satisfactory reconstruction quality. Moreover, the compressed depth data generated from this scheme can achieve better performance in view synthesis and gesture recognition applications compared with the conventional coding schemes because of the error control algorithm.

  15. High precision efficiency calibration of a HPGe detector

    International Nuclear Information System (INIS)

    Nica, N.; Hardy, J.C.; Iacob, V.E.; Helmer, R.G.

    2003-01-01

    Many experiments involving measurements of γ rays require a very precise efficiency calibration. Since γ-ray detection and identification also requires good energy resolution, the most commonly used detectors are of the coaxial HPGe type. We have calibrated our 70% HPGe to ∼ 0.2% precision, motivated by the measurement of precise branching ratios (BR) in superallowed 0 + → 0 + β decays. These BRs are essential ingredients in extracting ft-values needed to test the Standard Model via the unitarity of the Cabibbo-Kobayashi-Maskawa matrix, a test that it currently fails by more than two standard deviations. To achieve the required high precision in our efficiency calibration, we measured 17 radioactive sources at a source-detector distance of 15 cm. Some of these were commercial 'standard' sources but we achieved the highest relative precision with 'home-made' sources selected because they have simple decay schemes with negligible side feeding, thus providing exactly matched γ-ray intensities. These latter sources were produced by us at Texas A and M by n-activation or by nuclear reactions. Another critical source among the 17 was a 60 Co source produced by Physikalisch-Technische Bundesanstalt, Braunschweig, Germany: its absolute activity was quoted to better than 0.06%. We used it to establish our absolute efficiency, while all the other sources were used to determine relative efficiencies, extending our calibration over a large energy range (40-3500 keV). Efficiencies were also determined with Monte Carlo calculations performed with the CYLTRAN code. The physical parameters of the Ge crystal were independently determined and only two (unmeasurable) dead-layers were adjusted, within physically reasonable limits, to achieve precise absolute agreement with our measured efficiencies. The combination of measured efficiencies at more than 60 individual energies and Monte Carlo calculations to interpolate between them allows us to quote the efficiency of our

  16. Nd isotopes, U-Pb single grain and SHRIMP zircon ages from basement rocks of the Tocantin Province

    International Nuclear Information System (INIS)

    Fuck, R.A.; Dantas, E.L.; Pimentel, M.M.; Junges, S.L.; Moraes, R

    2001-01-01

    , which were interpreted as minimum ages of the igneous protoliths. Here we present a preliminary Nd isotope survey on basement gneiss and associated rocks sampled along a transect from Arraias to Porto Nacional, Tocantins. Single zircon U-Pb determinations and two SHRIMP U-Pb zircon ages are also presented. This study aims to assess the ages of rocks and sources involved in the continental crust generation of the northern segment of the Tocantins Province. The main goal is to identify different geochronologic provinces or crustal blocks and provide age constraints on the timing of crustal evolution recorded in the basement gneiss. U-Pb single crystal zircon and Sm-Nd whole rock isotopic analyses were carried out at the geochronology laboratory, Universidade de Brasilia. SHRIMP analyses were performed at Australian National University, Canberra (au)

  17. Petrochemical and Sr-Nd isotope investigations of Cretaceous intrusive rocks and their enclaves in the Togouchi-Yoshiwa district, northwest Hiroshima prefecture, SW Japan

    International Nuclear Information System (INIS)

    Ishioka, Jun; Iizumi, Shigeru

    2003-01-01

    Petrographic, petrochemical and Sr-Nd isotopic data are presented for granitoids and microdioritic enclaves from two Cretaceous stocks (Togouchi granodiorite and Tateiwayama granite porphyry) from the Togouchi-Yoshiwa district, northwest Hiroshima prefecture, SW Japan. The data are used to examine the genetic relationships between the microdioritic enclaves and their granitoid hosts. The granodiorite, granite porphyry and the microdioritic enclaves are all calc-alkaline in nature, and belong to the I-type ilmenite series. The Togouchi graniodiorite has a Rb-Sr whole rock isochron age of 85.6±4.7 Ma with an initial Sr isotope ratio (SrI) of 0.70634±0.00012 (2σ). The Tateiwayama granite porphyry has a slightly younger Rb-Sr whole isochron age (77.4±3.1 Ma) but similar SrI of 0.70653±0.00015, suggesting that both stocks may have been derived from the same source. Despite diverse whole rock chemistry, the microdioritic enclaves in the respective intrusives have quite similar initial Sr and Nd isotope ratios, suggesting that they formed by fractional crystallization of a single magma, and also that the source of the enclaves in both intrusives had similar geochemical characteristics. In both stocks, however, the enclaves have distinctly lower initial Sr isotope ratios than their respective host rocks, indicating that they were derived from a different source than their hosts. In view of the geochemical and Sr-Nd isotope data, we infer that the enclave magmas were derived from a similar LILE- and LREE-enriched source to that of the Cretaceous basalts and gabbroic-dioritic rocks that are sporadically distributed in SW Japan. Such mafic to intermediate magmas were probably derived from the upper mantle, and transferred both heat and material to the lower crust, thus producing granitic magmas by partial melting. Successive mafic magmas or their differentiates could then have been injected into the granitic magma chamber, trapped and quenched, resulting in the formation

  18. High precision frequency estimation for harpsichord tuning classification

    OpenAIRE

    Tidhar, D.; Mauch, M.; Dixon, S.

    2010-01-01

    We present a novel music signal processing task of classifying the tuning of a harpsichord from audio recordings of standard musical works. We report the results of a classification experiment involving six different temperaments, using real harpsichord recordings as well as synthesised audio data. We introduce the concept of conservative transcription, and show that existing high-precision pitch estimation techniques are sufficient for our task if combined with conservative transcription. In...

  19. High precision straw tube chamber with cathode readout

    International Nuclear Information System (INIS)

    Bychkov, V.N.; Golutvin, I.A.; Ershov, Yu.V.

    1992-01-01

    The high precision straw chamber with cathode readout was constructed and investigated. The 10 mm straws were made of aluminized mylar strip with transparent longitudinal window. The X coordinate information has been taken from the cathode strips as induced charges and investigated via centroid method. The spatial resolution σ=120 μm has been obtained with signal/noise ratio about 60. The possible ways for improving the signal/noise ratio have been described. 7 refs.; 8 figs

  20. A high precision straw tube chamber with cathode readout

    International Nuclear Information System (INIS)

    Bychkov, V.N.; Golutvin, I.A.; Ershov, Yu.V.; Zubarev, E.V.; Ivanov, A.B.; Lysiakov, V.N.; Makhankov, A.V.; Movchan, S.A.; Peshekhonov, V.D.; Preda, T.

    1993-01-01

    The high precision straw chamber with cathode readout was constructed and investigated. The 10 mm diameter straws were made of aluminized Mylar with transparent longitudinal window. The X-coordinate information has been taken from cathode strips as induced charges and investigated with the centroid method. The spatial resolution σ x =103 μm was obtained at a signal-to-noise ratio of about 70. The possible ways to improve the signal-to-noise ratio are discussed. (orig.)

  1. Developing and implementing a high precision setup system

    Science.gov (United States)

    Peng, Lee-Cheng

    The demand for high-precision radiotherapy (HPRT) was first implemented in stereotactic radiosurgery using a rigid, invasive stereotactic head frame. Fractionated stereotactic radiotherapy (SRT) with a frameless device was developed along a growing interest in sophisticated treatment with a tight margin and high-dose gradient. This dissertation establishes the complete management for HPRT in the process of frameless SRT, including image-guided localization, immobilization, and dose evaluation. The most ideal and precise positioning system can allow for ease of relocation, real-time patient movement assessment, high accuracy, and no additional dose in daily use. A new image-guided stereotactic positioning system (IGSPS), the Align RT3C 3D surface camera system (ART, VisionRT), which combines 3D surface images and uses a real-time tracking technique, was developed to ensure accurate positioning at the first place. The uncertainties of current optical tracking system, which causes patient discomfort due to additional bite plates using the dental impression technique and external markers, are found. The accuracy and feasibility of ART is validated by comparisons with the optical tracking and cone-beam computed tomography (CBCT) systems. Additionally, an effective daily quality assurance (QA) program for the linear accelerator and multiple IGSPSs is the most important factor to ensure system performance in daily use. Currently, systematic errors from the phantom variety and long measurement time caused by switching phantoms were discovered. We investigated the use of a commercially available daily QA device to improve the efficiency and thoroughness. Reasonable action level has been established by considering dosimetric relevance and clinic flow. As for intricate treatments, the effect of dose deviation caused by setup errors remains uncertain on tumor coverage and toxicity on OARs. The lack of adequate dosimetric simulations based on the true treatment coordinates from

  2. Geochemistry and Nd-isotope systematics of chemical and terrigenous sediments from the Dun Mountain Ophiolite, New Zealand

    International Nuclear Information System (INIS)

    Sivell, W.J.

    2002-01-01

    . Metalliferous contributions to red and green TA in the overlying terrigenous sedimentary sequence also link these facies to early DMOB back-arc eruptives. The red and green TA pass upwards into ungraded Atomodesmid-bearing grey TA, implying turbidite deposition in a shallowing marine environment. The (mainly andesitic) TA show systematic trends of decreasing Eu/Eu* and ε Nd (T) with increasing Ε-REE, La/Y, Th/Sc, and SiO 2 . Th abundances and Th/Sc ratios (up to 1.6) in the TA are akin to those of calc-alkaline magmas in continental arcs, and are significantly greater than island-arc or ophiolitic volcanics. A narrow range of positive ε Nd (T) values (+0.5 to +2.0) for the TA suggests a young differentiated continental arc source, less dissected than the quartzofeldspathic plutonic provenance for the Torlesse (ε Nd (T) N /Yb N = 2.5-2.8) in the sandstones resemble island-arc tholeiites (IAT). The breccias have low Eu/Eu* (c. 0.72), Ce N /Yb N = 1.6, Th/Sc (0.1-0.2), and Tb N /Yb N c. 1.0, features transitional between the sandstones and DMOB plagiogranites. Importantly, the sandstones and breccias show high positive initial Nd ratios (ε Nd (T) = +5 to +8) akin to values for Brook Street IAT (ε Nd (T) = +9). This implies juvenile (mantle-derived) source rocks for both the mafic and felsic younger terrigenous sediments, compatible with crustal residence (mean provenance) ages less than for the TA. Little continental input is permitted by Nd-isotopic data for these rocks. Whereas the early DMOB pillow basalt - chemical sediment - TA assemblage was emplaced in a back-arc setting, with influx of detritus in part from an active continental margin (possibly within the New England Orogen), the younger DMOB terrigenous sediment association shows a close kinship with bimodal DMOB magmatism related to infant arc volcanic centres in an extensional forearc regime. Turbidite sands and mass-flow deposits were shed into proximal fault-bound basins isolated from continental clastic

  3. High-precision two-dimensional atom localization via quantum interference in a tripod-type system

    International Nuclear Information System (INIS)

    Wang, Zhiping; Yu, Benli

    2014-01-01

    A scheme is proposed for high-precision two-dimensional atom localization in a four-level tripod-type atomic system via measurement of the excited state population. It is found that because of the position-dependent atom–field interaction, the precision of 2D atom localization can be significantly improved by appropriately adjusting the system parameters. Our scheme may be helpful in laser cooling or atom nanolithography via high-precision and high-resolution atom localization. (letter)

  4. A Study of Particle Beam Spin Dynamics for High Precision Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Andrew J. [Northern Illinois Univ., DeKalb, IL (United States)

    2017-05-01

    In the search for physics beyond the Standard Model, high precision experiments to measure fundamental properties of particles are an important frontier. One group of such measurements involves magnetic dipole moment (MDM) values as well as searching for an electric dipole moment (EDM), both of which could provide insights about how particles interact with their environment at the quantum level and if there are undiscovered new particles. For these types of high precision experiments, minimizing statistical uncertainties in the measurements plays a critical role. \\\\ \\indent This work leverages computer simulations to quantify the effects of statistical uncertainty for experiments investigating spin dynamics. In it, analysis of beam properties and lattice design effects on the polarization of the beam is performed. As a case study, the beam lines that will provide polarized muon beams to the Fermilab Muon \\emph{g}-2 experiment are analyzed to determine the effects of correlations between the phase space variables and the overall polarization of the muon beam.

  5. Strategies for high-precision Global Positioning System orbit determination

    Science.gov (United States)

    Lichten, Stephen M.; Border, James S.

    1987-01-01

    Various strategies for the high-precision orbit determination of the GPS satellites are explored using data from the 1985 GPS field test. Several refinements to the orbit determination strategies were found to be crucial for achieving high levels of repeatability and accuracy. These include the fine tuning of the GPS solar radiation coefficients and the ground station zenith tropospheric delays. Multiday arcs of 3-6 days provided better orbits and baselines than the 8-hr arcs from single-day passes. Highest-quality orbits and baselines were obtained with combined carrier phase and pseudorange solutions.

  6. High-precision multi-node clock network distribution.

    Science.gov (United States)

    Chen, Xing; Cui, Yifan; Lu, Xing; Ci, Cheng; Zhang, Xuesong; Liu, Bo; Wu, Hong; Tang, Tingsong; Shi, Kebin; Zhang, Zhigang

    2017-10-01

    A high precision multi-node clock network for multiple users was built following the precise frequency transmission and time synchronization of 120 km fiber. The network topology adopts a simple star-shaped network structure. The clock signal of a hydrogen maser (synchronized with UTC) was recovered from a 120 km telecommunication fiber link and then was distributed to 4 sub-stations. The fractional frequency instability of all substations is in the level of 10 -15 in a second and the clock offset instability is in sub-ps in root-mean-square average.

  7. Designing compensator of dual servo system for high precision positioning

    International Nuclear Information System (INIS)

    Choi, Hyeun Seok; Song, Chi Woo; Han, Chang Soo; Choi, Tae Hoon; Lee, Nak Kyu; Na, Kyung Hwan

    2003-01-01

    The high precision positioning mechanism is used in various industrial fields. It is used in semiconductor manufacturing line, test instrument, bioengineering, and MEMS and so on. This paper presents a positioning mechanism with dual servo system. Dual servo system consists of a coarse stage and a fine motion stage. The course stage is driven by VCM and the actuator of fine stage is the PZT. The purposes of dual servo system are stability, higher bandwidth, and robustness. Lead compensator is applied to this control system, and is designed by PQ method. Designed compensator can improve property of positioning mechanism

  8. International workshop on advanced materials for high precision detectors. Proceedings

    International Nuclear Information System (INIS)

    Nicquevert, B.; Hauviller, C.

    1994-01-01

    These proceedings gather together the contributions to the Workshop on Advanced Materials for High Precision Detectors, which was held from 28-30 September 1994 in Archamps, Haute-Savoie, France. This meeting brought together international experts (researchers, physicists and engineers) in the field of advanced materials and their use in high energy physics detectors or spacecraft applications. Its purpose was to discuss the status of the different materials currently in use in the structures of detectors and spacecraft, together with their actual performances, technological implications and future prospects. Environmental effects, such as those of moisture and radiation, were discussed, as were design and manufacturing technologies. Some case studies were presented. (orig.)

  9. High precision analysis of trace lithium isotope by thermal ionization mass spectrometry

    International Nuclear Information System (INIS)

    Tang Lei; Liu Xuemei; Long Kaiming; Liu Zhao; Yang Tianli

    2010-01-01

    High precision analysis method of ng lithium by thermal ionization mass spectrometry is developed. By double-filament measurement,phosphine acid ion enhancer and sample pre-baking technique,the precision of trace lithium analysis is improved. For 100 ng lithium isotope standard sample, relative standard deviation is better than 0.086%; for 10 ng lithium isotope standard sample, relative standard deviation is better than 0.90%. (authors)

  10. The πNN coupling from high precision np charge exchange at 162 MeV

    International Nuclear Information System (INIS)

    Nilsson, J.; Blomgren, J.; Conde, H.; Elmgren, K.; Olsson, N.; Ericson, T.E.O.; Uppsala Univ.; Jonsson, O.; Nilsson, L.; Loiseau, B.; Ringbom, A.

    1995-02-01

    Differential cross sections for unpolarized neutrons of 162 MeV have been measured to high precision with particular attention to the absolute normalisation. These data can be extrapolated precisely and model-independently to the pion pole and give a πNN coupling constant g 2 =14.6±0.3 or f 2 =0.0808±0.0017. This is higher than recently suggested values. (author) 24 refs.; 3 figs.; 1 tab

  11. A Miniaturized Colorimeter with a Novel Design and High Precision for Photometric Detection

    OpenAIRE

    Jun-Chao Yan; Yan Chen; Yu Pang; Jan Slavik; Yun-Fei Zhao; Xiao-Ming Wu; Yi Yang; Si-Fan Yang; Tian-Ling Ren

    2018-01-01

    Water quality detection plays an increasingly important role in environmental protection. In this work, a novel colorimeter based on the Beer-Lambert law was designed for chemical element detection in water with high precision and miniaturized structure. As an example, the colorimeter can detect phosphorus, which was accomplished in this article to evaluate the performance. Simultaneously, a modified algorithm was applied to extend the linear measurable range. The colorimeter encompassed a ne...

  12. Present status and future aspects of highly precise radiotherapy

    International Nuclear Information System (INIS)

    Oita, Masataka; Takegawa, Yoshihiro; Maezawa, Hiroshi; Ikushima, Hitoshi; Osaki, Kyosuke; Nishitani, Hiromu

    2006-01-01

    This review describes about therapeutic equipments, irradiation technology, actual practice of highly precise radiotherapy (RT) and its tasks in future. Development of radiation equipments has made the therapy highly precise. At present, there are reportedly 836 linacs and 23 microtrons in Japan (March, 2005), most of which are computerized, new generation equipments. Image-guided RT, CT-linac system, real-time tumor-tracking RT (RTRT), tomotherapy and cyberknife are introduced owing to development of concerned devices and equipments. In addition, there are 7 facilities with proton and/or heavy ion beams. In parallel with the machine development above, irradiation has become to that from 2D to 3D by multi-gate technique with use of multi-leaf collimator and intensity-modulated RT is introduced. RTRT is an example of 4D RT. Practically, stereotactic irradiation (STI) to brain tumor has resulted in 1-year cumulative survival rate of 58% in 16 cases (23 foci, median size 1.2 cm and volume 0.57 ml) with median dose of 21.0 Gy in authors' hospital. STI in the early stage lung cancers is also practically conducted without severe adverse effects. Future tasks involve the further development of irradiation techniques and RT planning, QA/QC system, and raising of experts in related fields, which is a national problem. (T.I.)

  13. High-Precision Computation: Mathematical Physics and Dynamics

    International Nuclear Information System (INIS)

    Bailey, D.H.; Barrio, R.; Borwein, J.M.

    2010-01-01

    At the present time, IEEE 64-bit oating-point arithmetic is suficiently accurate for most scientic applications. However, for a rapidly growing body of important scientic computing applications, a higher level of numeric precision is required. Such calculations are facilitated by high-precision software packages that include high-level language translation modules to minimize the conversion e ort. This pa- per presents a survey of recent applications of these techniques and provides someanalysis of their numerical requirements. These applications include supernova simulations, climate modeling, planetary orbit calculations, Coulomb n-body atomic systems, studies of the one structure constant, scattering amplitudes of quarks, glu- ons and bosons, nonlinear oscillator theory, experimental mathematics, evaluation of orthogonal polynomials, numerical integration of ODEs, computation of periodic orbits, studies of the splitting of separatrices, detection of strange nonchaotic at- tractors, Ising theory, quantum held theory, and discrete dynamical systems. We conclude that high-precision arithmetic facilities are now an indispensable compo- nent of a modern large-scale scientic computing environment.

  14. High-Precision Computation: Mathematical Physics and Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, D. H.; Barrio, R.; Borwein, J. M.

    2010-04-01

    At the present time, IEEE 64-bit oating-point arithmetic is suficiently accurate for most scientic applications. However, for a rapidly growing body of important scientic computing applications, a higher level of numeric precision is required. Such calculations are facilitated by high-precision software packages that include high-level language translation modules to minimize the conversion e ort. This pa- per presents a survey of recent applications of these techniques and provides someanalysis of their numerical requirements. These applications include supernova simulations, climate modeling, planetary orbit calculations, Coulomb n-body atomic systems, studies of the one structure constant, scattering amplitudes of quarks, glu- ons and bosons, nonlinear oscillator theory, experimental mathematics, evaluation of orthogonal polynomials, numerical integration of ODEs, computation of periodic orbits, studies of the splitting of separatrices, detection of strange nonchaotic at- tractors, Ising theory, quantum held theory, and discrete dynamical systems. We conclude that high-precision arithmetic facilities are now an indispensable compo- nent of a modern large-scale scientic computing environment.

  15. Video-rate or high-precision: a flexible range imaging camera

    Science.gov (United States)

    Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.; Payne, Andrew D.; Conroy, Richard M.; Godbaz, John P.; Jongenelen, Adrian P. P.

    2008-02-01

    A range imaging camera produces an output similar to a digital photograph, but every pixel in the image contains distance information as well as intensity. This is useful for measuring the shape, size and location of objects in a scene, hence is well suited to certain machine vision applications. Previously we demonstrated a heterodyne range imaging system operating in a relatively high resolution (512-by-512) pixels and high precision (0.4 mm best case) configuration, but with a slow measurement rate (one every 10 s). Although this high precision range imaging is useful for some applications, the low acquisition speed is limiting in many situations. The system's frame rate and length of acquisition is fully configurable in software, which means the measurement rate can be increased by compromising precision and image resolution. In this paper we demonstrate the flexibility of our range imaging system by showing examples of high precision ranging at slow acquisition speeds and video-rate ranging with reduced ranging precision and image resolution. We also show that the heterodyne approach and the use of more than four samples per beat cycle provides better linearity than the traditional homodyne quadrature detection approach. Finally, we comment on practical issues of frame rate and beat signal frequency selection.

  16. Radio emission from Supernovae and High Precision Astrometry

    Science.gov (United States)

    Perez-Torres, M. A.

    1999-11-01

    The present thesis work makes contributions in two scientific fronts: differential astrometry over the largest angular scales ever attempted (approx. 15 arcdegrees) and numerical simulations of radio emission from very young supernovae. In the first part, we describe the results of the use of very-long-baseline interferometry (VLBI) in one experiment designed to measure with very high precision the angular distance between the radio sources 1150+812 (QSO) and 1803+784 (BL Lac). We observed the radio sources on 19 November 1993 using an intercontinental array of radio telescopes, which simultaneously recorded at 2.3 and 8.4 GHz. VLBI differential astrometry is capable, Nature allowing, of yielding source positions with precisions well below the milliarcsecond level. To achieve this precision, we first had to accurately model the rotation of the interferometric fringes via the most precise models of Earth Orientation Parameters (EOP; precession, polar motion and UT1, nutation). With this model, we successfully connected our phase delay data at both frequencies and, using difference astrometric techniques, determined the coordinates of 1803+784 relative to those of 1150+812-within the IERS reference frame--with an standard error of about 0.6 mas in each coordinate. We then corrected for several effects including propagation medium (mainly the atmosphere and ionosphere), and opacity and source-structure effects within the radio sources. We stress that our dual-frequency measurements allowed us to accurately subtract the ionosphere contribution from our data. We also used GPS-based TEC measurements to independently find the ionosphere contribution, and showed that these contributions agree with our dual-frequency measurements within about 2 standard deviations in the less favorables cases (the longest baselines), but are usually well within one standard deviation. Our estimates of the relative positions, whether using dual-frequency-based or GPS-based ionosphere

  17. The SFD - 80 M high precision double axis facing lathe

    International Nuclear Information System (INIS)

    Bran, T.; Dragomir, I.; Rusu, I.; Stanciu, S.; Niculceanu, F.; Nica, O.; Popescu, M.; Bailescu, V.; Burcea, Gh.; Turcanu, V.

    2001-01-01

    A high precision double axis facing lathe was designed for machining the 'final end-cup' by exterior conical lathing. The lathe is semi-automatic and includes two independent identical units. The general constructive, dimensional and functional characteristics are presented as well as the specific power consumptions. As compared to other machines able to perform the same operations this machine presents the following novel aspects: - it is dedicated from the design stage to the workpiece to be machined; - the splinting speed is quasi-constant all along the processing span (irrespective of the cutting diameter at which the tool is fixed, in its trajectory generating the exterior cone). At 100% and 80% nominal power values the yield is 240 workpiece/hour and 192 workpiece/hour, respectively

  18. High Precision Renormalization Group Study of the Roughening Transition

    CERN Document Server

    Hasenbusch, M; Pinn, K

    1994-01-01

    We confirm the Kosterlitz-Thouless scenario of the roughening transition for three different Solid-On-Solid models: the Discrete Gaussian model, the Absolute-Value-Solid-On-Solid model and the dual transform of the XY model with standard (cosine) action. The method is based on a matching of the renormalization group flow of the candidate models with the flow of a bona fide KT model, the exactly solvable BCSOS model. The Monte Carlo simulations are performed using efficient cluster algorithms. We obtain high precision estimates for the critical couplings and other non-universal quantities. For the XY model with cosine action our critical coupling estimate is $\\beta_R^{XY}=1.1197(5)$. For the roughening coupling of the Discrete Gaussian and the Absolute-Value-Solid-On-Solid model we find $K_R^{DG}=0.6645(6)$ and $K_R^{ASOS}=0.8061(3)$, respectively.

  19. Optimal dynamic performance for high-precision actuators/stages

    International Nuclear Information System (INIS)

    Preissner, C.; Lee, S.-H.; Royston, T. J.; Shu, D.

    2002-01-01

    System dynamic performance of actuator/stage groups, such as those found in optical instrument positioning systems and other high-precision applications, is dependent upon both individual component behavior and the system configuration. Experimental modal analysis techniques were implemented to determine the six degree of freedom stiffnesses and damping for individual actuator components. These experimental data were then used in a multibody dynamic computer model to investigate the effect of stage group configuration. Running the computer model through the possible stage configurations and observing the predicted vibratory response determined the optimal stage group configuration. Configuration optimization can be performed for any group of stages, provided there is stiffness and damping data available for the constituent pieces

  20. High-precision isotopic characterization of USGS reference materials by TIMS and MC-ICP-MS

    Science.gov (United States)

    Weis, Dominique; Kieffer, Bruno; Maerschalk, Claude; Barling, Jane; de Jong, Jeroen; Williams, Gwen A.; Hanano, Diane; Pretorius, Wilma; Mattielli, Nadine; Scoates, James S.; Goolaerts, Arnaud; Friedman, Richard M.; Mahoney, J. Brian

    2006-08-01

    The Pacific Centre for Isotopic and Geochemical Research (PCIGR) at the University of British Columbia has undertaken a systematic analysis of the isotopic (Sr, Nd, and Pb) compositions and concentrations of a broad compositional range of U.S. Geological Survey (USGS) reference materials, including basalt (BCR-1, 2; BHVO-1, 2), andesite (AGV-1, 2), rhyolite (RGM-1, 2), syenite (STM-1, 2), granodiorite (GSP-2), and granite (G-2, 3). USGS rock reference materials are geochemically well characterized, but there is neither a systematic methodology nor a database for radiogenic isotopic compositions, even for the widely used BCR-1. This investigation represents the first comprehensive, systematic analysis of the isotopic composition and concentration of USGS reference materials and provides an important database for the isotopic community. In addition, the range of equipment at the PCIGR, including a Nu Instruments Plasma MC-ICP-MS, a Thermo Finnigan Triton TIMS, and a Thermo Finnigan Element2 HR-ICP-MS, permits an assessment and comparison of the precision and accuracy of isotopic analyses determined by both the TIMS and MC-ICP-MS methods (e.g., Nd isotopic compositions). For each of the reference materials, 5 to 10 complete replicate analyses provide coherent isotopic results, all with external precision below 30 ppm (2 SD) for Sr and Nd isotopic compositions (27 and 24 ppm for TIMS and MC-ICP-MS, respectively). Our results also show that the first- and second-generation USGS reference materials have homogeneous Sr and Nd isotopic compositions. Nd isotopic compositions by MC-ICP-MS and TIMS agree to within 15 ppm for all reference materials. Interlaboratory MC-ICP-MS comparisons show excellent agreement for Pb isotopic compositions; however, the reproducibility is not as good as for Sr and Nd. A careful, sequential leaching experiment of three first- and second-generation reference materials (BCR, BHVO, AGV) indicates that the heterogeneity in Pb isotopic compositions

  1. Hf-Nd isotope constraints on the origin of the Cretaceous Caribbean plateau and its relationship to the Galápagos plume

    Science.gov (United States)

    Thompson, P. M. E.; Kempton, P. D.; White, R. V.; Kerr, A. C.; Tarney, J.; Saunders, A. D.; Fitton, J. G.; McBirney, A.

    2004-01-01

    Formation of the Cretaceous Caribbean plateau, including the komatiites of Gorgona, has been linked to the currently active Galápagos hotspot. We use Hf-Nd isotopes and trace element data to characterise both the Caribbean plateau and the Galápagos hotspot, and to investigate the relationship between them. Four geochemical components are identified in the Galápagos mantle plume: two 'enriched' components with ɛHf and ɛNd similar to enriched components observed in other mantle plumes, one moderately enriched component with high Nb/Y, and a fourth component which most likely represents depleted MORB source mantle. The Caribbean plateau basalt data form a linear array in Hf-Nd isotope space, consistent with mixing between two mantle components. Combined Hf-Nd-Pb-Sr-He isotope and trace element data from this study and the literature suggest that the more enriched Caribbean end member corresponds to one or both of the enriched components identified on Galápagos. Likewise, the depleted end member of the array is geochemically indistinguishable from MORB and corresponds to the depleted component of the Galápagos system. Enriched basalts from Gorgona partially overlap with the Caribbean plateau array in ɛHf vs. ɛNd, whereas depleted basalts, picrites and komatiites from Gorgona have a high ɛHf for a given ɛNd, defining a high- ɛHf depleted end member that is not observed elsewhere within the Caribbean plateau sequences. This component is similar, however, in terms of Hf-Nd-Pb-He isotopes and trace elements to the depleted plume component recognised in basalts from Iceland and along the Reykjanes Ridge. We suggest that the Caribbean plateau represents the initial outpourings of the ancestral Galápagos plume. Absence of a moderately enriched, high Nb/Y component in the older Caribbean plateau (but found today on the island of Floreana) is either due to changing source compositions of the plume over its 90 Ma history, or is an artifact of limited sampling. The

  2. The Cambrian to Devonian odyssey of the Brabant Massif within Avalonia: A review with new zircon ages, geochemistry, Sm-Nd isotopes, stratigraphy and palaeogeography

    Science.gov (United States)

    Linnemann, Ulf; Herbosch, Alain; Liégeois, Jean-Paul; Pin, Christian; Gärtner, Andreas; Hofmann, Mandy

    2012-05-01

    This study provides an up-to-date and comprehensive review of the Early Palaeozoic evolution of the Brabant Massif belonging to the Anglo-Brabant Deformation Belt. Situated at the southeastern side of Avalonia microplate, it is the only well-known part of the northern passive margin of the Rheic Ocean. The Cambrian-Silurian sedimentary pile is > 13 km thick, with > 9 km for the Cambrian only. The unraveling of this continuous registration reflects the successive rifting and drifting of Avalonia from the Gondwana mainland, followed by soft-collisional processes with Baltica and finally the formation of Laurussia. Based on recently established detailed stratigraphy, sedimentology and basin development, on U-Pb LA-ICP-MS analyses of igneous and detrital zircon grains along with geochemical data including Sm-Nd isotopes, a new geodynamic and palaeogeographic evolution is proposed. Brabant Megasequence 1 (lower Cambrian to lowermost Ordovician, > 9 km thick) represents an embayment of the peri-Gondwanan rift from which the Rheic Ocean has evolved. Detrital zircon ages demonstrate that the Brabant is a typical peri-Gondwanan terrane with a major Pan-African (Neoproterozoic age) and a mixed West African and Amazonian source (Palaeoproterozoic, Archaean and some Mesoproterozoic age). The transition towards the Avalonia drifting is marked by an unconformity and a short volcanic episode. The northward drift of Avalonia towards Baltica is recorded by the Megasequence 2 (Middle to Upper Ordovician, 1.3 km thick). The source for Mesoproterozoic zircons vanished, as the result of the Rheic Ocean opening and the isolation from Amazonian sources. The transition to Megasequence 3 is marked by a drastic change in palaeobathymetry and an important (sub)volcanic episode during a tectonic instability period (460-430 Ma), reflecting the Avalonia-Baltica soft docking as also shown by the reappearance of Mesoproterozoic detrital zircons, typical of Baltica. Unradiogenic Nd isotope

  3. The clay mineral and Sr-Nd isotopic composition for fine-grained fraction of sediments from northwestern South China Sea: implications for sediment provenance

    Science.gov (United States)

    Cai, G.

    2013-12-01

    *Guanqiang Cai caiguanqiang@sina.com Guangzhou Marine Geological Survey, Guangzhou, 510760, P.R. China As the largest marginal sea in the western pacific, the South China Sea (SCS) receives large amount of terrigenous material annually through numerous rivers from surrounding continents and islands, which make it as the good place for the study of source to sink process. Yet few studies put emphasis on the northwestern continental shelf and slope in the SCS, even though most of the detrital materials derived from the Red River and Hainan Island are deposited in this area, and northwestern shelf plays a significant role in directly linking the South China, the Indochina and the South China Sea and thus controlling the source to sink process of terrestrial sediment. We presented the clay mineral and Sr-Nd isotopic composition of fine-grained fraction for sediments from northwestern SCS, in order to identify sediment source and transportation. The results show that the clay mineral of northwestern SCS sediments are mainly illite (30%~59%), smectite (20%~40%) and kaolinite (8%~35%), with minor chlorite. The illite chemical index varies between 0.19 and 0.75 with an average of 0.49, indicating an intensive hydrolysis in the source region. The 87Sr/86Sr ratios of sediments range from 0.716288 to 0.734416 (average of 0.724659), and ɛ Nd(0) values range from -10.31 to -11.62 (average of -10.93), which suggest that the source rocks of these sediments are derived from continental crust. The Hainan Island is an important source for sediments deposited in the nearshore and western shelf, especially for illite, kaolinite and smectite clay minerals. Furthermore, the relatively high contents of kaolinite and smectite in sediments from eastern shelf and southern slope of Hainan Island are also controlled by the supply of terrigenous materials from Hainan, which cannot be resulted from sedimentary differentiation of the Pearl and Red river sediments. And the correlation analysis

  4. High-precision multiband spectroscopy of ultracold fermions in a nonseparable optical lattice

    Science.gov (United States)

    Fläschner, Nick; Tarnowski, Matthias; Rem, Benno S.; Vogel, Dominik; Sengstock, Klaus; Weitenberg, Christof

    2018-05-01

    Spectroscopic tools are fundamental for the understanding of complex quantum systems. Here, we demonstrate high-precision multiband spectroscopy in a graphenelike lattice using ultracold fermionic atoms. From the measured band structure, we characterize the underlying lattice potential with a relative error of 1.2 ×10-3 . Such a precise characterization of complex lattice potentials is an important step towards precision measurements of quantum many-body systems. Furthermore, we explain the excitation strengths into different bands with a model and experimentally study their dependency on the symmetry of the perturbation operator. This insight suggests the excitation strengths as a suitable observable for interaction effects on the eigenstates.

  5. High-precision efficiency calibration of a high-purity co-axial germanium detector

    Energy Technology Data Exchange (ETDEWEB)

    Blank, B., E-mail: blank@cenbg.in2p3.fr [Centre d' Etudes Nucléaires de Bordeaux Gradignan, UMR 5797, CNRS/IN2P3, Université de Bordeaux, Chemin du Solarium, BP 120, 33175 Gradignan Cedex (France); Souin, J.; Ascher, P.; Audirac, L.; Canchel, G.; Gerbaux, M.; Grévy, S.; Giovinazzo, J.; Guérin, H.; Nieto, T. Kurtukian; Matea, I. [Centre d' Etudes Nucléaires de Bordeaux Gradignan, UMR 5797, CNRS/IN2P3, Université de Bordeaux, Chemin du Solarium, BP 120, 33175 Gradignan Cedex (France); Bouzomita, H.; Delahaye, P.; Grinyer, G.F.; Thomas, J.C. [Grand Accélérateur National d' Ions Lourds, CEA/DSM, CNRS/IN2P3, Bvd Henri Becquerel, BP 55027, F-14076 CAEN Cedex 5 (France)

    2015-03-11

    A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and γ-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived online sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed β decays for tests of the weak-interaction standard model.

  6. Genesis of Neoproterozoic granitoid magmatism in the Eastern Aracuai Fold Belt, eastern Brazil: field, geochemical and Sr-Nd isotopic evidence

    International Nuclear Information System (INIS)

    Celino, Joil Jose; Botelho, Nilson Francisquini; Pimentel, Marcio Martins

    2000-01-01

    The Neoproterozoic granitoid magmatism of the Aracuai Fold Belt (AFB) is an important element for the discussion of the evolution of this belt and its relationships with the African counterpart, the West Congo Belt. In the eastern part of the AFB, four different granitoid suites were recognized. The Nanuque Suite (NQS) comprises syn-tectonic peraluminous cordierite-bearing monzogranites. The Sao Paulinho Suite (SPS) consists of Th-rich peraluminous two mica or biotite-only granitoids. Calc-alkalic granitoids with magmatic epidote were grouped into the Itagimirim Suite (ITS) and post-tectonic charnockitic rocks were grouped into the Salomao Suite (SLS). Sm-Nd mineral isochron and Rb- isochron yielded ages of yielded ages of respectively 761 Ma and 714 Ma for the Nanuque and Sao Paulino suites. The general Sr-Nd isotopic characteristics of the granitoid suites and some country rocks indicate that the parental magmas were mostly the product of melting of the Paraiba do Sul metasediments. The chronological and genetic evolution the Neoproterozoic plutonism can be envisaged in a model of est-dipping subduction zone, followed by a continental collision between the Brasiliano/Pan-African (Brazil) and Congo (Africa cratons and final episodes of uplift and collapse. (author)

  7. Pb sbnd Sr sbnd Nd isotopic data of Indian Ocean ridges: new evidence of large-scale mapping of mantle heterogeneities

    Science.gov (United States)

    Hamelin, Bruno; Dupré, Bernard; Allègre, Claude J.

    1986-01-01

    A Pb sbnd Sr sbnd Nd isotope study of South West and East Indian Ridges confirms that the Indian Ocean belongs to a specific regional isotopic domain, as previously suggested by the results from islands of this ocean. The isotopic domain defined by the Indian MORB is indeed different from that of the North Atlantic and East Pacific Oceans. This demonstrates that the convective circulation of the upper mantle does not allow a rapid homogenization from one region to the other. The isotopic data of the Indian ridges can be interpreted by a contamination model, in which the depleted upper mantle (identical to that under the North Atlantic) is contaminated by two different types of contaminant, one corresponding to the source of the "central Indian Ocean" islands (Amsterdam, St. Paul, Marion, Prince Edward, Réunion, Rodriguez, Mauritius), and the other to a source similar to that of Walvis or Ninety East aseismic ridges. These two contaminants would have contributed to the ridge volcanism in different proportions over time.

  8. A high precision semi-analytic mass function

    Energy Technology Data Exchange (ETDEWEB)

    Del Popolo, Antonino [Dipartimento di Fisica e Astronomia, University of Catania, Viale Andrea Doria 6, I-95125 Catania (Italy); Pace, Francesco [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, The University of Manchester, Manchester, M13 9PL (United Kingdom); Le Delliou, Morgan, E-mail: adelpopolo@oact.inaf.it, E-mail: francesco.pace@manchester.ac.uk, E-mail: delliou@ift.unesp.br [Instituto de Física Teorica, Universidade Estadual de São Paulo (IFT-UNESP), Rua Dr. Bento Teobaldo Ferraz 271, Bloco 2—Barra Funda, 01140-070 São Paulo, SP Brazil (Brazil)

    2017-03-01

    In this paper, extending past works of Del Popolo, we show how a high precision mass function (MF) can be obtained using the excursion set approach and an improved barrier taking implicitly into account a non-zero cosmological constant, the angular momentum acquired by tidal interaction of proto-structures and dynamical friction. In the case of the ΛCDM paradigm, we find that our MF is in agreement at the 3% level to Klypin's Bolshoi simulation, in the mass range M {sub vir} = 5 × 10{sup 9} h {sup −1} M {sub ⊙}–−5 × 10{sup 14} h {sup −1} M {sub ⊙} and redshift range 0 ∼< z ∼< 10. For z = 0 we also compared our MF to several fitting formulae, and found in particular agreement with Bhattacharya's within 3% in the mass range 10{sup 12}–10{sup 16} h {sup −1} M {sub ⊙}. Moreover, we discuss our MF validity for different cosmologies.

  9. A high-precision synchronization circuit for clock distribution

    International Nuclear Information System (INIS)

    Lu Chong; Tan Hongzhou; Duan Zhikui; Ding Yi

    2015-01-01

    In this paper, a novel structure of a high-precision synchronization circuit, HPSC, using interleaved delay units and a dynamic compensation circuit is proposed. HPSCs are designed for synchronization of clock distribution networks in large-scale integrated circuits, where high-quality clocks are required. The application of a hybrid structure of a coarse delay line and dynamic compensation circuit performs roughly the alignment of the clock signal in two clock cycles, and finishes the fine tuning in the next three clock cycles with the phase error suppressed under 3.8 ps. The proposed circuit is implemented and fabricated using a SMIC 0.13 μm 1P6M process with a supply voltage at 1.2 V. The allowed operation frequency ranges from 200 to 800 MHz, and the duty cycle ranges between [20%, 80%]. The active area of the core circuits is 245 × 134 μm 2 , and the power consumption is 1.64 mW at 500 MHz. (paper)

  10. High precision relocation of earthquakes at Iliamna Volcano, Alaska

    Science.gov (United States)

    Statz-Boyer, P.; Thurber, C.; Pesicek, J.; Prejean, S.

    2009-01-01

    In August 1996, a period of elevated seismicity commenced beneath Iliamna Volcano, Alaska. This activity lasted until early 1997, consisted of over 3000 earthquakes, and was accompanied by elevated emissions of volcanic gases. No eruption occurred and seismicity returned to background levels where it has remained since. We use waveform alignment with bispectrum-verified cross-correlation and double-difference methods to relocate over 2000 earthquakes from 1996 to 2005 with high precision (~ 100??m). The results of this analysis greatly clarify the distribution of seismic activity, revealing distinct features previously hidden by location scatter. A set of linear earthquake clusters diverges upward and southward from the main group of earthquakes. The events in these linear clusters show a clear southward migration with time. We suggest that these earthquakes represent either a response to degassing of the magma body, circulation of fluids due to exsolution from magma or heating of ground water, or possibly the intrusion of new dikes beneath Iliamna's southern flank. In addition, we speculate that the deeper, somewhat diffuse cluster of seismicity near and south of Iliamna's summit indicates the presence of an underlying magma body between about 2 and 4??km depth below sea level, based on similar features found previously at several other Alaskan volcanoes. ?? 2009 Elsevier B.V.

  11. High precision target center determination from a point cloud

    Directory of Open Access Journals (Sweden)

    K. Kregar

    2013-10-01

    Full Text Available Many applications of terrestrial laser scanners (TLS require the determination of a specific point from a point cloud. In this paper procedure of high precision planar target center acquisition from point cloud is presented. The process is based on an image matching algorithm but before we can deal with raster image to fit a target on it, we need to properly determine the best fitting plane and project points on it. The main emphasis of this paper is in the precision estimation and propagation through the whole procedure which allows us to obtain precision assessment of final results (target center coordinates. Theoretic precision estimations – obtained through the procedure were rather high so we compared them with the empiric precision estimations obtained as standard deviations of results of 60 independently scanned targets. An χ2-test confirmed that theoretic precisions are overestimated. The problem most probably lies in the overestimated precisions of the plane parameters due to vast redundancy of points. However, empirical precisions also confirmed that the proposed procedure can ensure a submillimeter precision level. The algorithm can automatically detect grossly erroneous results to some extent. It can operate when the incidence angles of a laser beam are as high as 80°, which is desirable property if one is going to use planar targets as tie points in scan registration. The proposed algorithm will also contribute to improve TLS calibration procedures.

  12. Software Development of High-Precision Ephemerides of Solar System

    Directory of Open Access Journals (Sweden)

    Jong-Seob Shin

    1995-06-01

    Full Text Available We solved n-body problem about 9 plants, moon, and 4 minor planets with relativistic effect related to the basic equation of motion of the solar system. Perturbations including figure potential of the earth and the moon and solid earth tidal effect were considered on this relativistic equation of motion. The orientations employed precession and nutation for the earth, and lunar libration model with Eckert's lunar libration model based on J2000.0 were used for the moon. Finally, we developed heliocentric ecliptic position and velocity of each planet using this software package named the SSEG (Solar System Ephemerides Generator by long-term (more than 100 years simulation on CRAY-2S super computer, through testing each subroutine on personal computer and short-time (within 800days running on SUN3/280 workstation. Epoch of input data JD2440400.5 were adopted in order to compare our results to the data archived from JPL's DE200 by Standish and Newhall. Above equation of motion was integrated numerically having 1-day step-size interval through 40,000 days (about 110 years long as total computing interval. We obtained high-precision ephemerides of the planets with maximum error, less than ~2 x 10-8AU (≈±3km compared with DE200 data(except for mars and moon.

  13. SKLUST device for high-precision gluing of MWPC

    International Nuclear Information System (INIS)

    Amaglobeli, N.S.; Burov, R.V.; Sakandelidze, R.M.; Sakhelashvili, T.M.; Chiladze, B.G.; Glonti, G.L.; Glonti, L.N.

    2005-01-01

    The SKLUST device has been created for gluing precision plane-parallel anode, cathode of spacer bars and integral anode and cathode frames of the MWPCs or flat surfaces of the large-area cathode planes for them in the case that thin copper clad stesalit or glass-cloth-base laminate is used as the cathode, for example, for the CSC chambers. In contrast to usual gluing, in this device the glued components are not pressed to each other. SKLUST allows making high-precision products in laboratory conditions without preliminarily machining its components and receiving a precision article practically for any area at the plane parallelism from ±0.030 up to ±0.006 mm using a non-calibrated sheet of the foiled (or unfoiled) stesalit, glass-cloth-base laminate or other flexible materials to a tolerance for the thickness ±0.2-0.5 mm or worse. On the biggest of the existing devices it is possible to fabricate an article with the maximal sizes 2400x250 mm 2 at the thickness accuracy (6±0.015) mm (maximum deviation). Whereas in the technological cycle machining of blanks to the thickness or application of exact blanks is completely excluded, the manufacturing process becomes simpler, and the price of the articles essentially reduces, especially for mass production

  14. Ultracold Anions for High-Precision Antihydrogen Experiments.

    Science.gov (United States)

    Cerchiari, G; Kellerbauer, A; Safronova, M S; Safronova, U I; Yzombard, P

    2018-03-30

    Experiments with antihydrogen (H[over ¯]) for a study of matter-antimatter symmetry and antimatter gravity require ultracold H[over ¯] to reach ultimate precision. A promising path towards antiatoms much colder than a few kelvin involves the precooling of antiprotons by laser-cooled anions. Because of the weak binding of the valence electron in anions-dominated by polarization and correlation effects-only few candidate systems with suitable transitions exist. We report on a combination of experimental and theoretical studies to fully determine the relevant binding energies, transition rates, and branching ratios of the most promising candidate La^{-}. Using combined transverse and collinear laser spectroscopy, we determined the resonant frequency of the laser cooling transition to be ν=96.592 713(91)  THz and its transition rate to be A=4.90(50)×10^{4}  s^{-1}. Using a novel high-precision theoretical treatment of La^{-} we calculated yet unmeasured energy levels, transition rates, branching ratios, and lifetimes to complement experimental information on the laser cooling cycle of La^{-}. The new data establish the suitability of La^{-} for laser cooling and show that the cooling transition is significantly stronger than suggested by a previous theoretical study.

  15. High precision ray tracing in cylindrically symmetric electrostatics

    Energy Technology Data Exchange (ETDEWEB)

    Edwards Jr, David, E-mail: dej122842@gmail.com

    2015-11-15

    Highlights: • High precision ray tracing is formulated using power series techniques. • Ray tracing is possible for fields generated by solution to laplace's equation. • Spatial and temporal orders of 4–10 are included. • Precisions in test geometries of hemispherical deflector analyzer of ∼10{sup −20} have been obtained. • This solution offers a considerable extension to the ray tracing accuracy over the current state of art. - Abstract: With the recent availability of a high order FDM solution to the curved boundary value problem, it is now possible to determine potentials in such geometries with considerably greater accuracy than had been available with the FDM method. In order for the algorithms used in the accurate potential calculations to be useful in ray tracing, an integration of those algorithms needs to be placed into the ray trace process itself. The object of this paper is to incorporate these algorithms into a solution of the equations of motion of the ray and, having done this, to demonstrate its efficacy. The algorithm incorporation has been accomplished by using power series techniques and the solution constructed has been tested by tracing the medial ray through concentric sphere geometries. The testing has indicated that precisions of ray calculations of 10{sup −20} are now possible. This solution offers a considerable extension to the ray tracing accuracy over the current state of art.

  16. Precambrian tholeiitic-dacitic rock-suites and Cambrian ultramafic rocks in the Pennine nappe system of the Alps: Evidence from Sm-Nd isotopes and rare earth elements

    Science.gov (United States)

    Stille, P.; Tatsumoto, M.

    1985-04-01

    Major element, trace element and Sm-Nd isotope analyses were made of polymetamorphic hornblendefelses, plagioclase amphibolites and banded amphibolites from the Berisal complex in the Simplon area (Italy, Switzerland) to determine their age, origin and genetic relationships. In light of major and rare earth element data, the hornblendefelses are inferred to have originally been pyroxene-rich cumulates, the plagioclase amphibolites and the dark layers of the banded amphibolites to have been tholeiitic basalts and the light layers dacites. The Sm-Nd isotope data yield isochron ages of 475±81 Ma for the hornblendefelses, 1,018±59 Ma for the plagioclase amphibolites and 1,071±43 Ma for the banded amphibolites. The 1 Ga magmatic event is the oldest one ever found in the crystalline basement of the Pennine nappes. The Sm -Nd isotope data support the consanguinity of the tholeiitic dark layers and the dacitic light layers of the banded amphibolites with the tholeiitic plagioclase amphibolites and the ultramafic hornblendefelses. The initial ɛ Nd values indicate that all three rock types originated from sources depleted in light rare earth elements. We suggest that plagioclase and banded amphibolites were a Proterozoic tholeiite-dacite sequence that was strongly deformed and flattened during subsequent folding. The hornblendefelses are thought to be Cambrian intrusions of pyroxene-rich material.

  17. High-precision comparison of the antiproton-to-proton charge-to-mass ratio.

    Science.gov (United States)

    Ulmer, S; Smorra, C; Mooser, A; Franke, K; Nagahama, H; Schneider, G; Higuchi, T; Van Gorp, S; Blaum, K; Matsuda, Y; Quint, W; Walz, J; Yamazaki, Y

    2015-08-13

    Invariance under the charge, parity, time-reversal (CPT) transformation is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry--that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime--although it is model dependent. A number of high-precision CPT and Lorentz invariance tests--using a co-magnetometer, a torsion pendulum and a maser, among others--have been performed, but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available. Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion (H(-)) carried out in a Penning trap system. From 13,000 frequency measurements we compare the charge-to-mass ratio for the antiproton (q/m)p- to that for the proton (q/m)p and obtain (q/m)p-/(q/m)p − 1 =1(69) × 10(-12). The measurements were performed at cyclotron frequencies of 29.6 megahertz, so our result shows that the CPT theorem holds at the atto-electronvolt scale. Our precision of 69 parts per trillion exceeds the energy resolution of previous antiproton-to-proton mass comparisons as well as the respective figure of merit of the standard model extension by a factor of four. In addition, we give a limit on sidereal variations in the measured ratio of baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of |α − 1| < 8.7 × 10(-7).

  18. Progress Towards a High-Precision Infrared Spectroscopic Survey of the H_3^+ Ion

    Science.gov (United States)

    Perry, Adam J.; Hodges, James N.; Markus, Charles R.; Kocheril, G. Stephen; Jenkins, Paul A., II; McCall, Benjamin J.

    2015-06-01

    The trihydrogen cation, H_3^+, represents one of the most important and fundamental molecular systems. Having only two electrons and three nuclei, H_3^+ is the simplest polyatomic system and is a key testing ground for the development of new techniques for calculating potential energy surfaces and predicting molecular spectra. Corrections that go beyond the Born-Oppenheimer approximation, including adiabatic, non-adiabatic, relativistic, and quantum electrodynamic corrections are becoming more feasible to calculate. As a result, experimental measurements performed on the H_3^+ ion serve as important benchmarks which are used to test the predictive power of new computational methods. By measuring many infrared transitions with precision at the sub-MHz level it is possible to construct a list of the most highly precise experimental rovibrational energy levels for this molecule. Until recently, only a select handful of infrared transitions of this molecule have been measured with high precision (˜ 1 MHz). Using the technique of Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, we are aiming to produce the largest high-precision spectroscopic dataset for this molecule to date. Presented here are the current results from our survey along with a discussion of the combination differences analysis used to extract the experimentally determined rovibrational energy levels. O. Polyansky, et al., Phil. Trans. R. Soc. A (2012), 370, 5014. M. Pavanello, et al., J. Chem. Phys. (2012), 136, 184303. L. Diniz, et al., Phys. Rev. A (2013), 88, 032506. L. Lodi, et al., Phys. Rev. A (2014), 89, 032505. J. Hodges, et al., J. Chem. Phys (2013), 139, 164201.

  19. High precision patterning of ITO using femtosecond laser annealing process

    International Nuclear Information System (INIS)

    Cheng, Chung-Wei; Lin, Cen-Ying

    2014-01-01

    Highlights: • We have reported a process of fabrication of crystalline indium tin oxide (c-ITO) patterns using femtosecond laser-induced crystallization with a Gaussian beam profile followed by chemical etching. • The experimental results have demonstrated that the ablation and crystallization threshold fluences of a-ITO thin film are well-defined, the line width of the c-ITO patterns is controllable. • Fast fabrication of the two parallel sub-micro (∼0.5 μm) c-ITO line patterns using a single femtosecond laser beam and a single scanning path can be achieved. • A long-length sub-micro c-ITO line pattern is fabricated, and the feasibility of fabricating c-ITO patterns is confirmed, which are expected to be used in micro-electronics devices. - Abstract: High precision patterning of crystalline indium tin oxide (c-ITO) patterns on amorphous ITO (a-ITO) thin films by femtosecond laser-induced crystallization with a Gaussian beam profile followed by chemical etching is demonstrated. In the proposed approach, the a-ITO thin film is selectively transformed into a c-ITO structure via a low heat affect zone and the well-defined thresholds (ablation and crystallization) supplied by the femtosecond laser pulse. The experimental results show that by careful control of the laser fluence above the crystallization threshold, c-ITO patterns with controllable line widths and ridge-free characteristics can be accomplished. By careful control of the laser fluence above the ablation threshold, fast fabrication of the two parallel sub-micro c-ITO line patterns using a single femtosecond laser beam and single scanning path can be achieved. Along-length sub-micro c-ITO line pattern is fabricated, and the feasibility of fabricating c-ITO patterns is confirmed, which are expected to be used in micro-electronics devices

  20. a High Precision dem Extraction Method Based on Insar Data

    Science.gov (United States)

    Wang, Xinshuang; Liu, Lingling; Shi, Xiaoliang; Huang, Xitao; Geng, Wei

    2018-04-01

    In the 13th Five-Year Plan for Geoinformatics Business, it is proposed that the new InSAR technology should be applied to surveying and mapping production, which will become the innovation driving force of geoinformatics industry. This paper will study closely around the new outline of surveying and mapping and then achieve the TerraSAR/TanDEM data of Bin County in Shaanxi Province in X band. The studying steps are as follows; Firstly, the baseline is estimated from the orbital data; Secondly, the interferometric pairs of SAR image are accurately registered; Thirdly, the interferogram is generated; Fourth, the interferometric correlation information is estimated and the flat-earth phase is removed. In order to solve the phase noise and the discontinuity phase existing in the interferometric image of phase, a GAMMA adaptive filtering method is adopted. Aiming at the "hole" problem of missing data in low coherent area, the interpolation method of low coherent area mask is used to assist the phase unwrapping. Then, the accuracy of the interferometric baseline is estimated from the ground control points. Finally, 1 : 50000 DEM is generated, and the existing DEM data is used to verify the accuracy through statistical analysis. The research results show that the improved InSAR data processing method in this paper can obtain the high-precision DEM of the study area, exactly the same with the topography of reference DEM. The R2 can reach to 0.9648, showing a strong positive correlation.

  1. Drag-Free Motion Control of Satellite for High-Precision Gravity Field Mapping

    DEFF Research Database (Denmark)

    Ziegler, Bent Lindvig; Blanke, Mogens

    2002-01-01

    High precision mapping of the geoid and the Earth's gravity field are of importance to a wide range of ongoing studies in areas like ocean circulation, solid Earth physics and ice sheet dynamics. Using a satellite in orbit around the Earth gives the opportunity to map the Earth's gravity field in 3...... will compromise measurement accuracy, unless they are accurately compensated by on-board thrusters. The paper concerns the design of a control system to performing such delicate drag compensation. A six degrees-of-freedom model for the satellite is developed with the model including dynamics of the satellite...

  2. Mechanical optimisation of a high-precision fast wire scanner at CERN

    CERN Document Server

    Samuelsson, Sebastian; Veness, Raymond

    Wire scanners are instruments used to measure the transverse beam prole in particle accelerators by passing a thin wire through the particle beam. To avoid the issues of vacuum leakage through the bellows and wire failure related to current designs of wire scanners, a new concept for a wire scanner has been developed at CERN. This design has all moving parts inside the beam vacuum and has a nominal wire scanning speed of 20 m/s. The demands on the design associated with this together with the high precision requirements create a need for\

  3. Studies Of Submicron 3He Slabs Using A High Precision Torsional Oscillator

    International Nuclear Information System (INIS)

    Corcoles, Antonio; Casey, Andrew; Cowan, Brian; Saunders, John; Parpia, Jeevak; Bowley, Roger

    2006-01-01

    A high precision torsional oscillator has been used to study 3He films of thickness in the range 100 to 350 nm. In previous work we found that the films decoupled from the oscillator motion below 60 mK, in the Knudsen limit. This precluded observation of the superfluid transition. Here we report measurements using a torsional oscillator whose highly polished inner surfaces have been decorated with a low density of silver particles to act as random elastic scattering centres. This modification locks the normal film to the surface. A superfluid transition of the film is observed

  4. High-precision laser microcutting and laser microdrilling using diffractive beam-splitting and high-precision flexible beam alignment

    Science.gov (United States)

    Zibner, F.; Fornaroli, C.; Holtkamp, J.; Shachaf, Lior; Kaplan, Natan; Gillner, A.

    2017-08-01

    High-precision laser micro machining gains more importance in industrial applications every month. Optical systems like the helical optics offer highest quality together with controllable and adjustable drilling geometry, thus as taper angle, aspect ratio and heat effected zone. The helical optics is based on a rotating Dove-prism which is mounted in a hollow shaft engine together with other optical elements like wedge prisms and plane plates. Although the achieved quality can be interpreted as extremely high the low process efficiency is a main reason that this manufacturing technology has only limited demand within the industrial market. The objective of the research studies presented in this paper is to dramatically increase process efficiency as well as process flexibility. During the last years, the average power of commercial ultra-short pulsed laser sources has increased significantly. The efficient utilization of the high average laser power in the field of material processing requires an effective distribution of the laser power onto the work piece. One approach to increase the efficiency is the application of beam splitting devices to enable parallel processing. Multi beam processing is used to parallelize the fabrication of periodic structures as most application only require a partial amount of the emitted ultra-short pulsed laser power. In order to achieve highest flexibility while using multi beam processing the single beams are diverted and re-guided in a way that enables the opportunity to process with each partial beam on locally apart probes or semimanufactures.

  5. Sr and Nd isotopic characteristics of 1.77-1.58 Ga rift-related granites and volcanics of the Goiás tin province, central Brazil

    Directory of Open Access Journals (Sweden)

    MÁRCIO M. PIMENTEL

    2001-06-01

    Full Text Available Supracrustal rocks of the Araí Group, together with coeval A-type granites represent a ca. 1.77-1.58 Ga old continental rift in Brazil. Two granite families are identified: the older (1.77 Ga group forms small undeformed plutons, and the younger granites (ca. 1.58 Ga constitute larger, deformed plutons. Sr-Nd isotopic data for these rocks indicate that the magmatism is mostly product of re-melting of Paleoproterozoic sialic crust. Initial Sr ratios for both granite families are ca 0.726 and 0.720. Most TDM model ages are between 2.58 and 1.80 Ga. epsilonND(T values are between +3.6 and -11.9. Araí volcanics are bimodal, with basalts and dacites/rhyolites interlayered with continental sediments. The felsic volcanics show Nd isotopic characteristics which are very similar to the granites, and are also interpreted as reworking of Paleoproterozoic crust. Detrital sediments of the Araí Group revealed T DM model ages between 2.4 and 2.16 Ga, indicating that they are the product of erosion of Paleoproterozoic crust. The data indicate that the Araí rift system was established on crust that had just become stable after the Paleoproterozoic orogeny.As rochas supracrustais do Grupo Araí, e os granitos tipo-A associados, representam um rift continental paleo-mesoproterozóico. Duas famílias de granitos são identificadas: a mais antiga (ca. 1,77 Ga forma pequenos plutons circulares enquanto a mais jovem (ca. 1,58 Ga, constitui corpos maiores e deformados. Dados isotópicos Sr-Nd indicam que o magmatismo félsico é predominantemente o produto de re-fusão de crosta de idade paleoproterozóica. Razões 87Sr/86Sr iniciais das duas famílias são ca. 0,726 e 0,720. A maioria das idades modelo T DM caem no intervalo entre 2,58 e 1,80 Ga e os valores de épsilonND(T se distribuem entre +3.6 e -11.9. Rochas vulcânicas do Grupo Araí são bimodais, com basaltos e dacitos/riolitos intercalados em sedimentos continentais. As vulcânicas félsicas mostram

  6. Os-Hf-Sr-Nd isotope and PGE systematics of spinel peridotite xenoliths from Tok, SE Siberian craton: Effects of pervasive metasomatism in shallow refractory mantle

    Science.gov (United States)

    Ionov, Dmitri A.; Shirey, Steven B.; Weis, Dominique; Brügmann, Gerhard

    2006-01-01

    Os-Hf-Sr-Nd isotopes and PGE were determined in peridotite xenoliths carried to the surface by Quaternary alkali basaltic magmas in the Tokinsky Stanovik Range on the Aldan shield. These data constrain the timing and nature of partial melting and metasomatism in the lithospheric mantle beneath SE Siberian craton. The xenoliths range from the rare fertile spinel lherzolites to the more abundant, strongly metasomatised olivine-rich (70-84%) rocks. Hf-Sr-Nd isotope compositions of the xenoliths are mainly within the fields of oceanic basalts. Most metasomatised xenoliths have lower 143Nd / 144Nd and 176Hf / 177Hf and higher 87Sr / 86Sr than the host basalts indicating that the metasomatism is older and has distinct sources. A few xenoliths have elevated 176Hf / 177Hf (up to 0.2838) and plot above the Hf-Nd mantle array defined by oceanic basalts. 187Os / 188Os in the poorly metasomatised, fertile to moderately refractory (Al2O3 ≥ 1.6%) Tok peridotites range from 0.1156 to 0.1282, with oldest rhenium depletion ages being about 2 Ga. The 187Os / 188Os in these rocks show good correlations with partial melting indices (e.g. Al2O3, modal cpx); the intercept of the Al-187Os / 188Os correlation with lowest Al2O3 estimates for melting residues (∼0.3-0.5%) has a 187Os / 188Os of ∼0.109 suggesting that these peridotites may have experienced melt extraction as early as 2.8 Gy ago. 187Os / 188Os in the strongly metasomatised, olivine-rich xenoliths (0.6-1.3% Al2O3) ranges from 0.1164 to 0.1275 and shows no apparent links to modal or chemical compositions. Convex-upward REE patterns and high abundances of heavy to middle REE in these refractory rocks indicate equilibration with evolved silicate melts at high melt / rock ratios, which may have also variably elevated their 187Os / 188Os. This inference is supported by enrichments in Pd and Pt on chondrite-normalised PGE abundance patterns in some of the rocks. The melt extraction ages for the Tok suite of 2.0 to 2.8 Ga are

  7. A Miniaturized Colorimeter with a Novel Design and High Precision for Photometric Detection.

    Science.gov (United States)

    Yan, Jun-Chao; Chen, Yan; Pang, Yu; Slavik, Jan; Zhao, Yun-Fei; Wu, Xiao-Ming; Yang, Yi; Yang, Si-Fan; Ren, Tian-Ling

    2018-03-08

    Water quality detection plays an increasingly important role in environmental protection. In this work, a novel colorimeter based on the Beer-Lambert law was designed for chemical element detection in water with high precision and miniaturized structure. As an example, the colorimeter can detect phosphorus, which was accomplished in this article to evaluate the performance. Simultaneously, a modified algorithm was applied to extend the linear measurable range. The colorimeter encompassed a near infrared laser source, a microflow cell based on microfluidic technology and a light-sensitive detector, then Micro-Electro-Mechanical System (MEMS) processing technology was used to form a stable integrated structure. Experiments were performed based on the ammonium molybdate spectrophotometric method, including the preparation of phosphorus standard solution, reducing agent, chromogenic agent and color reaction. The device can obtain a wide linear response range (0.05 mg/L up to 7.60 mg/L), a wide reliable measuring range up to 10.16 mg/L after using a novel algorithm, and a low limit of detection (0.02 mg/L). The size of flow cell in this design is 18 mm × 2.0 mm × 800 μm, obtaining a low reagent consumption of 0.004 mg ascorbic acid and 0.011 mg ammonium molybdate per determination. Achieving these advantages of miniaturized volume, high precision and low cost, the design can also be used in automated in situ detection.

  8. A Miniaturized Colorimeter with a Novel Design and High Precision for Photometric Detection

    Directory of Open Access Journals (Sweden)

    Jun-Chao Yan

    2018-03-01

    Full Text Available Water quality detection plays an increasingly important role in environmental protection. In this work, a novel colorimeter based on the Beer-Lambert law was designed for chemical element detection in water with high precision and miniaturized structure. As an example, the colorimeter can detect phosphorus, which was accomplished in this article to evaluate the performance. Simultaneously, a modified algorithm was applied to extend the linear measurable range. The colorimeter encompassed a near infrared laser source, a microflow cell based on microfluidic technology and a light-sensitive detector, then Micro-Electro-Mechanical System (MEMS processing technology was used to form a stable integrated structure. Experiments were performed based on the ammonium molybdate spectrophotometric method, including the preparation of phosphorus standard solution, reducing agent, chromogenic agent and color reaction. The device can obtain a wide linear response range (0.05 mg/L up to 7.60 mg/L, a wide reliable measuring range up to 10.16 mg/L after using a novel algorithm, and a low limit of detection (0.02 mg/L. The size of flow cell in this design is 18 mm × 2.0 mm × 800 μm, obtaining a low reagent consumption of 0.004 mg ascorbic acid and 0.011 mg ammonium molybdate per determination. Achieving these advantages of miniaturized volume, high precision and low cost, the design can also be used in automated in situ detection.

  9. High Precision Stokes Polarimetry for Scattering Light using Wide Dynamic Range Intensity Detector

    Directory of Open Access Journals (Sweden)

    Shibata Shuhei

    2015-01-01

    Full Text Available This paper proposes a Stokes polarimetry for scattering light from a sample surface. To achieve a high accuracy measurement two approaches of an intensity detector and analysis algorism of a Stokes parameter were proposed. The dynamic range of this detector can achieve up to 1010 by combination of change of neutral-density (ND filters having different density and photon counting units. Stokes parameters can be measured by dual rotating of a retarder and an analyzer. The algorism of dual rotating polarimeter can be calibrated small linear diattenuation and linear retardance error of the retarder. This system can measured Stokes parameters from −20° to 70° of its scattering angle. It is possible to measure Stokes parameters of scattering of dust and scratch of optical device with high precision. This paper shows accuracy of this system, checking the polarization change of scattering angle and influence of beam size.

  10. Status and outlook of CHIP-TRAP: The Central Michigan University high precision Penning trap

    Science.gov (United States)

    Redshaw, M.; Bryce, R. A.; Hawks, P.; Gamage, N. D.; Hunt, C.; Kandegedara, R. M. E. B.; Ratnayake, I. S.; Sharp, L.

    2016-06-01

    At Central Michigan University we are developing a high-precision Penning trap mass spectrometer (CHIP-TRAP) that will focus on measurements with long-lived radioactive isotopes. CHIP-TRAP will consist of a pair of hyperbolic precision-measurement Penning traps, and a cylindrical capture/filter trap in a 12 T magnetic field. Ions will be produced by external ion sources, including a laser ablation source, and transported to the capture trap at low energies enabling ions of a given m / q ratio to be selected via their time-of-flight. In the capture trap, contaminant ions will be removed with a mass-selective rf dipole excitation and the ion of interest will be transported to the measurement traps. A phase-sensitive image charge detection technique will be used for simultaneous cyclotron frequency measurements on single ions in the two precision traps, resulting in a reduction in statistical uncertainty due to magnetic field fluctuations.

  11. High precision ages from the Torres del Paine Intrusion, Chile

    Science.gov (United States)

    Michel, J.; Baumgartner, L.; Cosca, M.; Ovtcharova, M.; Putlitz, B.; Schaltegger, U.

    2006-12-01

    The upper crustal bimodal Torres del Paine Intrusion, southern Chile, consists of the lower Paine-Mafic- Complex and the upper Paine-Granite. Geochronologically this bimodal complex is not well studied except for a few existing data from Halpern (1973) and Sanchez (2006). The aim of this study is to supplement the existing data and to constrain the age relations between the major magmatic pulses by applying high precision U-Pb dating on accessory zircons and 40Ar/39Ar-laser-step-heating-ages on biotites from the Torres del Paine Intrusion. The magmatic rocks from mafic complex are fine to medium-grained and vary in composition from quartz- monzonites to granodiorites and gabbros. Coarse-grained olivine gabbros have intruded these rocks in the west. The granitic body is represented by a peraluminous, biotite-orthoclase-granite and a more evolved leucocratic granite in the outer parts towards the host-rock. Field observations suggest a feeder-zone for the granite in the west and that the granite postdates the mafic complex. Two granite samples of the outermost margins in the Northeast and South were analyzed. The zircons were dated by precise isotope-dilution U-Pb techniques of chemically abraded single grains. The data are concordant within the analytical error and define weighted mean 206/238U ages of 12.59 ± 0.03 Ma and 12.58 ± 0.01 Ma for the two samples respectively. A 40Ar/39Ar-age for the second sample yield a date of 12.37 ± 0.11 Ma. Three 40Ar/39Ar -ages of biotites were obtained for rocks belonging to the mafic complex. A hbl-bio- granodiorite from the central part, approximately 150 m below the subhorizontal contact with the granite, gives an age of 12.81 ± 0.11 Ma. A hbl-bio-granodiorite and an olivine-gabbro west of the feeder-zone date at 12.42 ± 0.14 Ma and 12.49 ± 0.11 Ma, respectively. The obtained older age of 12.81 Ma for the granodiorite in the central part is consistent with structural relationships of brittle fracturing of the mafic

  12. High precision laser control of the ATLAS tile-calorimeter module mass production at JINR

    International Nuclear Information System (INIS)

    Batusov, V.; Budagov, Yu.; Flyagin, V.; Khubua, D.; Lomakin, Yu.; Lyablin, M.; Rusakovich, N.; Shabalin, D.; Topilin, N.; Nessi, M.

    2001-01-01

    We present a short description of our last few years experience in the quality control of the ATLAS hadron barrel tile-calorimeter module mass production at JINR. A Laser Measurement System (LMS) proposed and realized in Dubna guarantees a high-precision module assembly. The non-planarity of module size surfaces (1.9x5.6 m) controlled area is well within the required ±0.6 mm tolerance for each of JINR assembled modules. The module assembly technique achieved with the LMS system allows us to deliver to CERN one module every 2 weeks. This laser-based measurement system could be used in future for the control measurement of other large-scale units during the ATLAS assembly

  13. High-precision and low-cost vibration generator for low-frequency calibration system

    Science.gov (United States)

    Li, Rui-Jun; Lei, Ying-Jun; Zhang, Lian-Sheng; Chang, Zhen-Xin; Fan, Kuang-Chao; Cheng, Zhen-Ying; Hu, Peng-Hao

    2018-03-01

    Low-frequency vibration is one of the harmful factors that affect the accuracy of micro-/nano-measuring machines because its amplitude is significantly small and it is very difficult to avoid. In this paper, a low-cost and high-precision vibration generator was developed to calibrate an optical accelerometer, which is self-designed to detect low-frequency vibration. A piezoelectric actuator is used as vibration exciter, a leaf spring made of beryllium copper is used as an elastic component, and a high-resolution, low-thermal-drift eddy current sensor is applied to investigate the vibrator’s performance. Experimental results demonstrate that the vibration generator can achieve steady output displacement with frequency range from 0.6 Hz to 50 Hz, an analytical displacement resolution of 3.1 nm and an acceleration range from 3.72 mm s-2 to 1935.41 mm s-2 with a relative standard deviation less than 1.79%. The effectiveness of the high-precision and low-cost vibration generator was verified by calibrating our optical accelerometer.

  14. The STiC ASIC. High precision timing with silicon photomultipliers

    International Nuclear Information System (INIS)

    Harion, Tobias

    2015-01-01

    In recent years, Silicon Photomultipliers are being increasingly used for Time of Flight measurements in particle detectors. To utilize the high intrinsic time resolution of these sensors in detector systems, the development of specialized, highly integrated readout electronics is required. In this thesis, a mixed-signal application specific integrated circuit, named STiC, has been developed, characterized and integrated in a detector system. STiC has been specifically designed for high precision timing measurements with SiPMs, and is in particular dedicated to the EndoTOFPET-US project, which aims to achieve a coincidence time resolution of 200 ps FWHM and an energy resolution of less than 20% in an endoscopic positron emission tomography system. The chip integrates 64 high precision readout channels for SiPMs together with a digital core logic to process, store and transfer the recorded events to a data acquisition system. The performance of the chip has been validated in coincidence measurements using detector modules consisting of 3.1 x 3.1 x 15 mm 3 LYSO crystals coupled to Silicon Photomultipliers from Hamamatsu. The measurements show an energy resolution of 15% FWHM for the detection of 511 keV photons. A coincidence time resolution of 213 ps FWHM has been measured, which is among the best resolution values achieved to date with this detector topology. STiC has been integrated in the EndoTOFPET-US detector system and has been chosen as the baseline design for the readout of SiPM sensors in the Mu3e experiment.

  15. ACADEMIC TRAINING: Probing nature with high precision; particle traps, laser spectroscopy and optical combs

    CERN Multimedia

    Françoise Benz

    2002-01-01

    17, 18, 19 June LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 Probing nature with high precision; particle traps, laser spectroscopy and optical combs by G. GABRIELSE / Harvard University, USA Experiments with atomic energy scales probe nature and its symmetries with exquisite precision. Particle traps allow the manipulation of single charged particles for months at a time, allow the most accurate comparison of theory and experiment, and promise to allow better measurement of fundamental quantities like the fine structure constant. Ions and atoms can be probed with lasers that are phase locked to microwave frequency standards via optical combs, thus calibrating optical sources in terms of the official cesium second. A series of three lectures will illustrate what can be measured and discuss key techniques.  ACADEMIC TRAINING Françoise Benz Tel. 73127 francoise.benz@cern.ch

  16. A fast high-precision six-degree-of-freedom relative position sensor

    Science.gov (United States)

    Hughes, Gary B.; Macasaet, Van P.; Griswold, Janelle; Sison, Claudia A.; Lubin, Philip; Meinhold, Peter; Suen, Jonathan; Brashears, Travis; Zhang, Qicheng; Madajian, Jonathan

    2016-03-01

    Lasers are commonly used in high-precision measurement and profiling systems. Some laser measurement systems are based on interferometry principles, and others are based on active triangulation, depending on requirements of the application. This paper describes an active triangulation laser measurement system for a specific application wherein the relative position of two fixed, rigid mechanical components is to be measured dynamically with high precision in six degrees of freedom (DOF). Potential applications include optical systems with feedback to control for mechanical vibration, such as target acquisition devices with multiple focal planes. The method uses an array of several laser emitters mounted on one component. The lasers are directed at a reflective surface on the second component. The reflective surface consists of a piecewise-planar pattern such as a pyramid, or more generally a curved reflective surface such as a hyperbolic paraboloid. The reflected spots are sensed at 2-dimensional photodiode arrays on the emitter component. Changes in the relative position of the emitter component and reflective surface will shift the location of the reflected spots within photodiode arrays. Relative motion in any degree of freedom produces independent shifts in the reflected spot locations, allowing full six-DOF relative position determination between the two component positions. Response time of the sensor is limited by the read-out rate of the photodiode arrays. Algorithms are given for position determination with limits on uncertainty and sensitivity, based on laser and spot-sensor characteristics, and assuming regular surfaces. Additional uncertainty analysis is achievable for surface irregularities based on calibration data.

  17. The use of Nd isotopes to establish sedimentary provenance at inverted passive margins: The case of Andrelandia depositional cycle at the Riberia belt, Brazil

    International Nuclear Information System (INIS)

    Ragatky, D.; Tupinamba, M.; Duarte, B.P

    2001-01-01

    The Ribeira Belt (Almeida et al., 1973), in southeastern Brazil, is a Brasiliano/Pan-African belt that resulted from the agglutination of the Gondwana Supercontinent (750-500 Ma). The tectonic organization at its central segment can be defined by several tectono-stratigraphic domains (Heilbron et al., 1998, 2000). In general terms, each tectonic domain comprises: a) pre-1.8 Ga basement rocks; b) post-1.8 Ga metasedimentary cover including metabasic rocks of continental to MORB geochemical affinity; and c) Brasiliano-Pan African granitoids. U/Pb ages for zircon, titanite and monazite of both the pre-1.8 Ga basement and Brasiliano granitoids (Machado et al., 1996) reveal that basement gneisses were generated during the Transamazonian Orogeny, about 2.1 Ga. Peak metamorphic conditions (M1) of the Brasiliano Collage at the central Ribeira belt were reached at 590 - 565 Ma, with a second metamorphic event (M2) at 535 - 520 Ma (Machado et al., 1996). Our research area is located at the transition between the foreland and the hinterland of the Ribeira belt: the Occidental terrane. It represents a reworked margin of the Sao Francisco Craton, formerly known as a proterozoic tectonic plate. It is composed by two crustal scale thrust sheets (Andrelandia and Juiz de Fora domains) tangentially transported towards the foreland of Sao Francisco Craton. Despite the well-determined ages of the Transamazonic basement and Brasiliano granitic rocks (Machado et al. 1996), the sedimentary source of the siliciclastic cover at the Occidental terrane remains poorly known. In this case, the use of Nd isotopic system, due to its relative immobility, is an important additional tool of investigation in geological correlation between basement source areas and sedimentary cover. The siliciclastic sedimentary and metasedimentary rocks are formed by detritus of pre-existing crustal rocks and they could be formed by more than one source. Then, depleted mantle Nd model ages (T DM ) for sediments

  18. The size-isotopic evolution connection among layered mafic instrusions: Clues from a Sr-Nd isotopic study of a small complex

    Science.gov (United States)

    Poitrasson, Franck; Pin, Christian; Duthou, Jean-Louis; Platevoet, Bernard

    1994-05-01

    Several theoretical and experimental works have focused on the processes occuring in continental mafic magma chambers. In contrast, systematic isotopic studies of natural remnants of these latter remain scarce, although they can give fundamental constraints for theoretical studies. This is especially true if different layered complex with contrasting characteristics (e.g., different size) are compared. For this reason, we present the results of a Sr-Nd isotopic profile across a small layered mafic intrusion of Permian age exposed near Fozzano (SW Corsica). In the main zone of the layered section, decreasing Sr-87/Sr(sub i)-86 and increasing Nd-143/Nd(sub i)-144 are observed from less evolved (bottom) to more evolved (top) rocks. This peculiar pattern precludes assimilation and fractional crystallization (AFC) as a dominant mechanism in the petrogenesis of this body. Instead, we interpret this trend as reflecting the dilution of an early stage contaminated magma by several reinjections of fresh basalt in the chamber. In agreement with mineralogical and structural data, every cyclic unit is interpreted as a new magmatic input. On the basis of rough refill and fractional crystallization (RFC) calculations, the average volume for each reinjection is estimated to have been about 0.04 cu km. The cumulative volume of these injections would amount to about 75% of the total volume of the layered complex. This implies that reinjections were accompanied by an important increase of the volume of the chamber or by magma withdrawal by surface eruptions. The RFC mechanism documented within this small layered body constrasts with the isotopic pattern observed between several intrusions at the regional scale in SW Corsica, and within large continental mafic magma chambers elsewhere. In these cases the isotopic evolution is dominated by AFC processes, and there is no clear isotopic evidence for reinjections, unless major influx of fresh magma occurred. It is suggested that there is

  19. Crustal evolution of South American Platform based on Sm-Nd isotope geochemistry; Evolucao crustal da plataforma sul americana com base na geoquimica isotopica Sm-Nd

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Kei

    1998-07-01

    Sm-Nd isotopic systematics is relevant to the topics of origin and evolution the of continental crust, where model ages refer to the time when crustal material was differentiated from the upper mantle. Alternative interpretations are due to a lack of adequate information on crustal processes and the variable composition of the mantle sources. The Sm-Nd methods are presented, and applied on rock materials from the South American Platform. The main conclusions indicate juvenile accretion with higher growth rates (peaks), around 3.7-3.5 Ga ({approx} 0.5% in volume), 3.1 - 2.9 Ga ({approx}16%), 2.7 - 2.6 ({approx} 9%), 2.2 - 1.9 (35%) and 1.3-1.0 (7%). The continental growth curve indicates that about 35 % of the crust was formed by 2.5 Ga, 88% by 1.8 Ga and 99% by 1.0 Ga, and the remaining {approx} 1 % was added in the Phanerozoic. Rapid crustal growth occurred between 2.2 and 1.9 Ga. The main period of continental crust formation occurred during the Paleoproterozoic, corresponding to 54 % in volume. Sm-Nd model ages, when compared with the crystallisation ages of granitoid rocks, furnish a rough estimate of juvenile vs. reworked material. Within the South American Platform about 45% of juvenile continental crust is still preserved within tectonic provinces of different ages. The remainder represents continental crust reworked in younger tectono-thermal events. In particular crustal reworking was predominating over juvenile accretion during Meso-Neoproterozoic. The Transbrasiliano Lineament is a megasuture, active in the Neoproterozoic, which separates a large northwestern mass, including the Amazonian and Sao Luis Cratons, from a southeastern mass, formed by a collage of cratonic fragments, of which the Sao Francisco and Rio de La Plata are the largest. The crustal evolutions of these two large continental masses are considered individually, and can be resumed following form: I - Old Archean rocks (>3.4 Ga) are found only within the south-eastern part (Gaviao Block

  20. Geochronology, geochemistry and Hf–Sr–Nd isotopes of the ore-bearing syenite from the Shapinggou porphyry Mo deposit, East Qinling-Dabie orogenic belt

    Directory of Open Access Journals (Sweden)

    Tao He

    2016-12-01

    Full Text Available The Shapinggou Mo deposit is located in the western Dabie mountains, the eastern part of the Qinling-Dabie molybdenum orogenic belt. Shapinggou Mo deposit is a concealed deposit with the ore body mainly hosted by explosive breccia of Gaijing and the granite porphyry as well as the syenite of Shapinggou. Geochemistry study show that the SiO2 contents of Shapinggou syenite range from 61.74 to 69.93%, and the A/CNK from 0.95 to 1.06, classified as metaluminous to weak peraluminous, belonging to alkalic to shoshonitic series. The Mo deposits in Qinling Mo belt formed in two main periods, i.e., the first period occurred in to the Early Cretaceous (145–130 Ma, the second period in the late Early Cretaceous (130–110 Ma. Most of the Mo deposits in Dabie region formed in the second period. The results of zircon U–Pb show that the age of the Shapinggou syenite is 111.3 ± 1.2 Ma, which belongs to the second period. Proterozoic-Archean inherited zircons suggest that it may include some more ancient crustal material like Kongling group. The ɛHf(t values of Shapinggou syenite range from −15.6 to −8.0, TDM2(Hf from 1.7 to 2.16 Ga, respectively. The ɛNd(t values of the Shapinggou syenite range from −12.29 to −11.76, TDM2(Nd from 1.85 to 1.89 Ga, the 87Sr/86Sr from 0.709 to 0.710, respectively. Results of zircon Hf isotope and whole rock Sr–Nd isotope of Shapinggou syenite indicate that the Mo ore-forming materials were mainly generated from old Yangtze craton, e.g., gneiss from Dabie orogeny, mixed with some juvenal mantle materials. The geodynamics of the Shapinggou Mo deposit corresponded to an extension period in Eastern China, which caused by large scale lithospheric thinning. The delamination caused asthenosphere upwelling and crust-mantle interaction, which provided the ore-forming material and heat.

  1. High Precision GNSS Guidance for Field Mobile Robots

    Directory of Open Access Journals (Sweden)

    Ladislav Jurišica

    2012-11-01

    Full Text Available In this paper, we discuss GNSS (Global Navigation Satellite System guidance for field mobile robots. Several GNSS systems and receivers, as well as multiple measurement methods and principles of GNSS systems are examined. We focus mainly on sources of errors and investigate diverse approaches for precise measuring and effective use of GNSS systems for real-time robot localization. The main body of the article compares two GNSS receivers and their measurement methods. We design, implement and evaluate several mathematical methods for precise robot localization.

  2. Performance of the new high precision luminosity monitor of DELPHI

    International Nuclear Information System (INIS)

    Alvsvaag, S.J.; Maeland, O.A.; Klovning, A.; Benvenuti, A.C.; Giordano, V.; Guerzoni, M.; Navarria, F.L.; Perrotta, A.; Camporesi, T.; Obraztsov, V.; Paganoni, M.; Vallazza, E.; Bozzo, M.; Cereseto, R.; Barreira, G.; Espirito Santo, M.C.; Maio, A.; Onofre, A.; Peralta, L.; Pimenta, M.; Tome, B.; Carling, H.; Falk, E.; Hedberg, V.; Jarlskog, G.; Kronkvist, I.; Bonesini, M.; Chignoli, F.; Ferrari, P.; Gumenyuk, S.; Leoni, R.; Mazza, R.; Negri, P.; Petrovykh, L.; Terranova, F.; Dharmasiri, D.R.; Nossum, B.; Read, A.L.; Skaali, B.; Rohne, O.; Castellani, L.; Pegoraro, M.; Fenyuk, A.; Ivanyushenkov, I.; Karyukhin, A.; Konopliannikov, A.; Shalanda, N.; Sen'ko, V.; Vlasov, E.; Zaitsev, A.; Bigi, M.; Cassio, V.; Gamba, D.; Gouz, I.; Migliore, E.; Romero, A.; Simonetti, L.; Trapani, P.P.; Bari, M.; Della Ricca, G.; Lanceri, L.; Poropat, P.; Prest, M.

    1997-01-01

    The STIC calorimeter was installed in the DELPHI detector in 1994. The main goal is to measure the luminosity with an accuracy better than 0.1%. The calorimeter was built using the ''Shashlik'' technique. The light is collected by wavelength shifting fibers and readout by phototetrodes that can operate inside the magnetic field. The detector performance during the 1994-1995 data taking is presented. The different contributions to the systematic error on the luminosity measurement are discussed. (orig.)

  3. High-precision masses of 29-33Mg and the N=20 shell ''closure''

    International Nuclear Information System (INIS)

    Lunney, D.; Audi, G.; Gaulard, C.; Saint Simon, M. de; Thibault, C.; Vieira, N.

    2006-01-01

    High-precision mass measurements have been performed on the exotic magnesium isotopes 29-33 Mg using the MISTRAL radiofrequency spectrometer, especially suited for very short-lived nuclides. This method, combined with the powerful tool of resonant laser ionization at ISOLDE, has provided a significant reduction of uncertainty for the masses of the most exotic Mg isotopes: a relative error of 7 x 10 -7 was achieved for the weakly produced 33 Mg that has a half-life of only 90 ms. Moreover, the mass of 33 Mg is found to change by over 250 keV. Verifying and minimizing binding energy uncertainties in this region of the nuclear chart is important for understanding the lack of binding energy that is normally associated with magic numbers. (orig.)

  4. High-precision high-sensitivity clock recovery circuit for a mobile payment application

    International Nuclear Information System (INIS)

    Sun Lichong; Yan Na; Min Hao; Ren Wenliang

    2011-01-01

    This paper presents a fully integrated carrier clock recovery circuit for a mobile payment application. The architecture is based on a sampling-detection module and a charge pump phase locked loop. Compared with clock recovery in conventional 13.56 MHz transponders, this circuit can recover a high-precision consecutive carrier clock from the on/off keying (OOK) signal sent by interrogators. Fabricated by a SMIC 0.18-μm EEPROM CMOS process, this chip works from a single power supply as low as 1.5 V Measurement results show that this circuit provides 0.34% frequency deviation and 8 mV sensitivity. (semiconductor integrated circuits)

  5. Proposal for the determination of nuclear masses by high-precision spectroscopy of Rydberg states

    International Nuclear Information System (INIS)

    Wundt, B J; Jentschura, U D

    2010-01-01

    The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to the nuclear mass. As a consequence, spectroscopic measurements of Rydberg transitions can be used in order to precisely deduce nuclear masses. A possible application of this approach to hydrogen and deuterium, and hydrogen-like lithium and carbon is explored in detail. In order to complete the analysis, numerical and analytic calculations of the quantum electrodynamic self-energy remainder function for states with principal quantum number n = 5, ..., 8 and with angular momentum l = n - 1 and l = n - 2 are described (j = l +- 1/2).

  6. Proposal for the determination of nuclear masses by high-precision spectroscopy of Rydberg states

    Energy Technology Data Exchange (ETDEWEB)

    Wundt, B J; Jentschura, U D [Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409-0640 (United States)

    2010-06-14

    The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to the nuclear mass. As a consequence, spectroscopic measurements of Rydberg transitions can be used in order to precisely deduce nuclear masses. A possible application of this approach to hydrogen and deuterium, and hydrogen-like lithium and carbon is explored in detail. In order to complete the analysis, numerical and analytic calculations of the quantum electrodynamic self-energy remainder function for states with principal quantum number n = 5, ..., 8 and with angular momentum l = n - 1 and l = n - 2 are described (j = l {+-} 1/2).

  7. High precision optical fiber alignment using tube laser bending

    NARCIS (Netherlands)

    Folkersma, Ger; Römer, Gerardus Richardus, Bernardus, Engelina; Brouwer, Dannis Michel; Herder, Justus Laurens

    2016-01-01

    In this paper, we present a method to align optical fibers within 0.2 μm of the optimal position, using tube laser bending and in situ measuring of the coupling efficiency. For near-UV wavelengths, passive alignment of the fibers with respect to the waveguides on photonic integrated circuit chips

  8. High-precision photometry by telescope defocusing - IV

    DEFF Research Database (Denmark)

    Southworth, John; Hinse, T. C.; Dominik, M.

    2012-01-01

    We present photometric observations of four transits in the WASP-17 planetary system, obtained using telescope defocusing techniques and with scatters reaching 0.5 mmag per point. Our revised orbital period is 4.0 ± 0.6 s longer than previous measurements, a difference of 6.6σ, and does not suppo...

  9. The QCD coupling and parton distributions at high precision

    International Nuclear Information System (INIS)

    Bluemlein, Johannes

    2010-07-01

    A survey is given on the present status of the nucleon parton distributions and related precision calculations and precision measurements of the strong coupling constant α s (M 2 Z ). We also discuss the impact of these quantities on precision observables at hadron colliders. (orig.)

  10. The QCD coupling and parton distributions at high precision

    Energy Technology Data Exchange (ETDEWEB)

    Bluemlein, Johannes

    2010-07-15

    A survey is given on the present status of the nucleon parton distributions and related precision calculations and precision measurements of the strong coupling constant {alpha}{sub s}(M{sup 2}{sub Z}). We also discuss the impact of these quantities on precision observables at hadron colliders. (orig.)

  11. High Precision Survey and Alignment of Large Linear Accelerators

    CERN Document Server

    Prenting, J

    2004-01-01

    For the future linear accelerator TESLA the demanded accuracy for the alignment of the components is 0.5 mm horizontal and 0.2 mm vertical, both on each 600 m section. Other accelerators require similar accuracies. These demands can not be fulfilled with open-air geodetic methods, mainly because of refraction. Therefore the RTRS (Rapid Tunnel Reference Surveyor), a measurement train performing overlapping multipoint alignment on a reference network is being developed. Two refraction-free realizations of this concept are being developed at the moment: the first one (GeLiS) measures the horizontal co-ordinates using stretched wires, combined with photogrammetric split-image sensors in a distance measurement configuration. In areas of the tunnel where the accelerator is following the earth curvature GeLiS measures the height using a new hydrostatic leveling system. The second concept (LiCAS) is based on laser straightness monitors (LSM) combined with frequency scanning interferometry (FSI) in an evacuated system...

  12. Fabrication of high precision metallic freeform mirrors with magnetorheological finishing (MRF)

    Science.gov (United States)

    Beier, Matthias; Scheiding, Sebastian; Gebhardt, Andreas; Loose, Roman; Risse, Stefan; Eberhardt, Ramona; Tünnermann, Andreas

    2013-09-01

    The fabrication of complex shaped metal mirrors for optical imaging is a classical application area of diamond machining techniques. Aspherical and freeform shaped optical components up to several 100 mm in diameter can be manufactured with high precision in an acceptable amount of time. However, applications are naturally limited to the infrared spectral region due to scatter losses for shorter wavelengths as a result of the remaining periodic diamond turning structure. Achieving diffraction limited performance in the visible spectrum demands for the application of additional polishing steps. Magnetorheological Finishing (MRF) is a powerful tool to improve figure and finish of complex shaped optics at the same time in a single processing step. The application of MRF as a figuring tool for precise metal mirrors is a nontrivial task since the technology was primarily developed for figuring and finishing a variety of other optical materials, such as glasses or glass ceramics. In the presented work, MRF is used as a figuring tool for diamond turned aluminum lightweight mirrors with electroless nickel plating. It is applied as a direct follow-up process after diamond machining of the mirrors. A high precision measurement setup, composed of an interferometer and an advanced Computer Generated Hologram with additional alignment features, allows for precise metrology of the freeform shaped optics in short measuring cycles. Shape deviations less than 150 nm PV / 20 nm rms are achieved reliably for freeform mirrors with apertures of more than 300 mm. Characterization of removable and induced spatial frequencies is carried out by investigating the Power Spectral Density.

  13. Studies of Pulsed Signals in High-precision Experiments (Antarctica

    Directory of Open Access Journals (Sweden)

    Shapovalov S. N.,

    2013-07-01

    Full Text Available The paper presents the results of studies on pulsed signals in photocurrent (PCC-2 instrument, in the 565-nm LED spectrum, and in the atmospheric zenith spectrum (342.5 nm. According to the results of statistical analysis of data measurements for the period from 24.04.04 till 01.02.06 a correlation between the temporal distribution of pulsed signals in photocurrent PCC-2 and CA F10.7 cm (2800 MHz index and the total solar radiation (TSI was established. In the course of the parallel measurements of photocurrent in PCC-2 and fluctuations in the spectra frequencies of the LED and the atmosphere zenith, based on the average daily values of the standard deviation, the identical trend in the photocurrent pulse signals (PCC-2 and the fluctuations at 520-nm LED spectrum and 342.5-nm atmosphere zenith spectrum was detected (AvaSpec–2048 spectrometer.

  14. High precision neutron interferometer setup S18b

    International Nuclear Information System (INIS)

    Hasegawa, Y.; Lemmel, H.

    2011-01-01

    The present setup at S18 is a multi purpose instrument. It is used for both interferometry and a Bonse-Hart camera for USANS (Ultra Small Angle Neutron Scattering) spectroscopy with wide range tunability of wavelength. Some recent measurements demand higher stability of the instrument, which made us to propose a new setup dedicated particularly for neutron interferometer experiments requiring high phase stability. To keep both options available, we suggest building the new setup in addition to the old one. By extending the space of the present setup by 1.5 m to the upstream, both setups can be accommodated side by side. (authors)

  15. Observing exoplanet populations with high-precision astrometry

    Science.gov (United States)

    Sahlmann, Johannes

    2012-06-01

    This thesis deals with the application of the astrometry technique, consisting in measuring the position of a star in the plane of the sky, for the discovery and characterisation of extra-solar planets. It is feasible only with a very high measurement precision, which motivates the use of space observatories, the development of new ground-based astronomical instrumentation and of innovative data analysis methods: The study of Sun-like stars with substellar companions using CORALIE radial velocities and HIPPARCOS astrometry leads to the determination of the frequency of close brown dwarf companions and to the discovery of a dividing line between massive planets and brown dwarf companions; An observation campaign employing optical imaging with a very large telescope demonstrates sufficient astrometric precision to detect planets around ultra-cool dwarf stars and the first results of the survey are presented; Finally, the design and initial astrometric performance of PRIMA, ! a new dual-feed near-infrared interferometric observing facility for relative astrometry is presented.

  16. High precision silicon piezo resistive SMART pressure sensor

    International Nuclear Information System (INIS)

    Brown, Rod

    2005-01-01

    Instruments for test and calibration require a pressure sensor that is precise and stable. Market forces also dictate a move away from single measurand test equipment and, certainly in the case of pressure, away from single range equipment. A pressure 'module' is required which excels in pressure measurement but is interchangble with sensors for other measurands. A communications interface for such a sensor has been specified. Instrument Digital Output Sensor (IDOS) that permits this interchanagability and allows the sensor to be inside or outside the measuring instrument. This paper covers the design and specification of a silicon diaphragm piezo resistive SMART sensor using this interface. A brief history of instrument sensors will be given to establish the background to this development. Design choices of the silicon doping, bridge energisation method, temperature sensing, signal conversion, data processing, compensation method, communications interface will be discussed. The physical format of the 'in-instrument' version will be shown and then extended to the packaging design for the external version. Test results will show the accuracy achieved exceeds the target of 0.01%FS over a range of temperatures

  17. High precision silicon piezo resistive SMART pressure sensor

    Science.gov (United States)

    Brown, Rod

    2005-01-01

    Instruments for test and calibration require a pressure sensor that is precise and stable. Market forces also dictate a move away from single measurand test equipment and, certainly in the case of pressure, away from single range equipment. A pressure `module' is required which excels in pressure measurement but is interchangble with sensors for other measurands. A communications interface for such a sensor has been specified. Instrument Digital Output Sensor (IDOS) that permits this interchanagability and allows the sensor to be inside or outside the measuring instrument. This paper covers the design and specification of a silicon diaphragm piezo resistive SMART sensor using this interface. A brief history of instrument sensors will be given to establish the background to this development. Design choices of the silicon doping, bridge energisation method, temperature sensing, signal conversion, data processing, compensation method, communications interface will be discussed. The physical format of the `in-instrument' version will be shown and then extended to the packaging design for the external version. Test results will show the accuracy achieved exceeds the target of 0.01%FS over a range of temperatures.

  18. Parton distributions from high-precision collider data

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Richard D.; Del Debbio, Luigi; Groth-Merrild, Patrick [University of Edinburgh, The Higgs Centre for Theoretical Physics, Edinburgh (United Kingdom); Bertone, Valerio; Hartland, Nathan P.; Rojo, Juan [VU University, Department of Physics and Astronomy, Amsterdam (Netherlands); Nikhef Theory Group, Amsterdam (Netherlands); Carrazza, Stefano [CERN, Theoretical Physics Department, Geneva (Switzerland); Forte, Stefano [Universita di Milano, Tif Lab, Dipartimento di Fisica, Milano (Italy); INFN, Sezione di Milano, Milano (Italy); Guffanti, Alberto [Universita di Torino, Dipartimento di Fisica, Turin (Italy); INFN, Sezione di Torino, Turin (Italy); Kassabov, Zahari [Universita di Milano, Tif Lab, Dipartimento di Fisica, Milano (Italy); INFN, Sezione di Milano, Milano (Italy); Universita di Torino, Dipartimento di Fisica, Turin (Italy); INFN, Sezione di Torino, Turin (Italy); Latorre, Jose I. [Universitat de Barcelona, Departament de Fisica Quantica i Astrofisica, Barcelona (Spain); National University of Singapore, Center for Quantum Technologies, Singapore (Singapore); Nocera, Emanuele R.; Rottoli, Luca; Slade, Emma [University of Oxford, Rudolf Peierls Centre for Theoretical Physics, Oxford (United Kingdom); Ubiali, Maria [University of Cambridge, Cavendish Laboratory, HEP Group, Cambridge (United Kingdom); Collaboration: NNPDF Collaboration

    2017-10-15

    We present a new set of parton distributions, NNPDF3.1, which updates NNPDF3.0, the first global set of PDFs determined using a methodology validated by a closure test. The update is motivated by recent progress in methodology and available data, and involves both. On the methodological side, we now parametrize and determine the charm PDF alongside the light-quark and gluon ones, thereby increasing from seven to eight the number of independent PDFs. On the data side, we now include the D0 electron and muon W asymmetries from the final Tevatron dataset, the complete LHCb measurements of W and Z production in the forward region at 7 and 8 TeV, and new ATLAS and CMS measurements of inclusive jet and electroweak boson production. We also include for the first time top-quark pair differential distributions and the transverse momentum of the Z bosons from ATLAS and CMS. We investigate the impact of parametrizing charm and provide evidence that the accuracy and stability of the PDFs are thereby improved. We study the impact of the new data by producing a variety of determinations based on reduced datasets. We find that both improvements have a significant impact on the PDFs, with some substantial reductions in uncertainties, but with the new PDFs generally in agreement with the previous set at the one-sigma level. The most significant changes are seen in the light-quark flavor separation, and in increased precision in the determination of the gluon. We explore the implications of NNPDF3.1 for LHC phenomenology at Run II, compare with recent LHC measurements at 13 TeV, provide updated predictions for Higgs production cross-sections and discuss the strangeness and charm content of the proton in light of our improved dataset and methodology. The NNPDF3.1 PDFs are delivered for the first time both as Hessian sets, and as optimized Monte Carlo sets with a compressed number of replicas. (orig.)

  19. Computational Calorimetry: High-Precision Calculation of Host–Guest Binding Thermodynamics

    Science.gov (United States)

    2015-01-01

    We present a strategy for carrying out high-precision calculations of binding free energy and binding enthalpy values from molecular dynamics simulations with explicit solvent. The approach is used to calculate the thermodynamic profiles for binding of nine small molecule guests to either the cucurbit[7]uril (CB7) or β-cyclodextrin (βCD) host. For these systems, calculations using commodity hardware can yield binding free energy and binding enthalpy values with a precision of ∼0.5 kcal/mol (95% CI) in a matter of days. Crucially, the self-consistency of the approach is established by calculating the binding enthalpy directly, via end point potential energy calculations, and indirectly, via the temperature dependence of the binding free energy, i.e., by the van’t Hoff equation. Excellent agreement between the direct and van’t Hoff methods is demonstrated for both host–guest systems and an ion-pair model system for which particularly well-converged results are attainable. Additionally, we find that hydrogen mass repartitioning allows marked acceleration of the calculations with no discernible cost in precision or accuracy. Finally, we provide guidance for accurately assessing numerical uncertainty of the results in settings where complex correlations in the time series can pose challenges to statistical analysis. The routine nature and high precision of these binding calculations opens the possibility of including measured binding thermodynamics as target data in force field optimization so that simulations may be used to reliably interpret experimental data and guide molecular design. PMID:26523125

  20. Water mass circulation and weathering inputs in the Labrador Sea based on coupled Hf-Nd isotope compositions and rare earth element distributions

    Science.gov (United States)

    Filippova, Alexandra; Frank, Martin; Kienast, Markus; Rickli, Jörg; Hathorne, Ed; Yashayaev, Igor M.; Pahnke, Katharina

    2017-02-01

    The Labrador Sea is one of the key areas for deep water formation driving the Atlantic thermohaline circulation and thus plays an important role in Northern Hemisphere climatic fluctuations. In order to better constrain the overturning processes and the origins of the distinct water masses, combined dissolved Hf-Nd isotopic compositions and rare earth element (REE) distribution patterns were obtained from four water depth profiles along a section across the Labrador Sea. These were complemented by one surface sample off the southern tip of Greenland, three shallow water samples off the coast of Newfoundland, and two deep water samples off Nova Scotia. Although light REEs are markedly enriched in the surface waters off the coast of Newfoundland compared to north Atlantic waters, the REE concentration profiles are essentially invariant throughout the water column across the Labrador Sea. The hafnium concentrations of surface waters exhibit a narrow range between 0.6 and 1 pmol/kg but are not significantly higher than at depth. Neodymium isotope signatures (ɛNd) vary from unradiogenic values between -16.8 and -14.9 at the surface to more radiogenic values near -11.0 at the bottom of the Labrador Sea mainly reflecting the advection of the Denmark Strait Overflow Water and North East Atlantic Deep Water, the signatures of which are influenced by weathering contributions from Icelandic basalts. Unlike Nd, water column radiogenic Hf isotope signatures (ɛHf) are more variable representing diverse weathering inputs from the surrounding landmasses. The least radiogenic seawater ɛHf signatures (up to -11.7) are found in surface waters close to Greenland and near the Canadian margin. This reflects the influence of recirculating Irminger Current Waters, which are affected by highly unradiogenic inputs from Greenland. A three to four ɛHf unit difference is observed between Denmark Strait Overflow Water (ɛHf ∼ -4) and North East Atlantic Deep Water (ɛHf ∼ -0

  1. Sr- and Nd- isotope variations along the Pleistocene San Pedro - Linzor volcanic chain, N. Chile: Tracking the influence of the upper crustal Altiplano-Puna Magma Body

    Science.gov (United States)

    Godoy, Benigno; Wörner, Gerhard; Le Roux, Petrus; de Silva, Shanaka; Parada, Miguel Ángel; Kojima, Shoji; González-Maurel, Osvaldo; Morata, Diego; Polanco, Edmundo; Martínez, Paula

    2017-07-01

    thicker ( 20 km) and more melt-dominated ( 25% vol. partial melt) while lower 87Sr/86Sr, and higher 143Nd/144Nd reveal thinner marginal zones of the APMB where lower contents of partial melt (< 10% vol) involves reduced interactions. The lowest Sr-isotope ratios, and higher Nd-isotope ratios (where available) occur in magmas erupted outside the APMB (e.g. San Pedro, Lascar and Aucanquilcha volcanoes), indicating a diminished influence of crustal partial melts on parental mafic magmas. These geochemical parameters provide a useful tracer for the extent and significance of crustal partial melt bodies in magma genesis in the Central Andes.

  2. The history of a continent from U-Pb ages of zircons from Orinoco River sand and Sm-Nd isotopes in Orinoco basin river sediments

    Science.gov (United States)

    Goldstein, S.L.; Arndt, N.T.; Stallard, R.F.

    1997-01-01

    igneous and metamorphic history of these sources, as recorded by the detrital zircons, is that of the Orinoco basin basement. This implies that, despite evidence of fast sedimentary recycling, global similarities in Nd crustal-residence ages, and the probability of cross-continent mixing through continental drift, the sedimentary material carried by individual rivers is mainly derived from the crystalline basement in the basin. The global semblance in Nd isotope ratios in major river sediments and atmospheric dusts results from the averaging effect of large-scale sampling of the continents, which are heterogeneous in age on smaller regional scales. A large portion of the continental crust in the Orinoco basin formed during the Trans-Amazonian orogeny at 2.0-2.1 Ga, and smaller portions formed both earlier, at ??? 2.8 Ga, and later, after 1.6 Ga. These observations, which are consistent with the relative sizes of crustal age provinces in the Orinoco basin, indicate that sediments from the lower Orinoco and Andean tributaries contain 25-35% of material added to the crust since Trans-Amazonian times. Nd model ages of these sediments underestimate the average crust-formation age of the basement of the Orinoco basin by only about 10%. If this relationship holds in other river basins, then Nd model ages of major rivers and wind blown particulates indicate that the mean age of the continental crust is ??? 1.9-2 Ga. ?? 1997 Elsevier Science B.V.

  3. An automatic high precision registration method between large area aerial images and aerial light detection and ranging data

    Science.gov (United States)

    Du, Q.; Xie, D.; Sun, Y.

    2015-06-01

    The integration of digital aerial photogrammetry and Light Detetion And Ranging (LiDAR) is an inevitable trend in Surveying and Mapping field. We calculate the external orientation elements of images which identical with LiDAR coordinate to realize automatic high precision registration between aerial images and LiDAR data. There are two ways to calculate orientation elements. One is single image spatial resection using image matching 3D points that registered to LiDAR. The other one is Position and Orientation System (POS) data supported aerotriangulation. The high precision registration points are selected as Ground Control Points (GCPs) instead of measuring GCPs manually during aerotriangulation. The registration experiments indicate that the method which registering aerial images and LiDAR points has a great advantage in higher automation and precision compare with manual registration.

  4. The NANOGrav 11-year Data Set: High-precision Timing of 45 Millisecond Pulsars

    Science.gov (United States)

    Arzoumanian, Zaven; Brazier, Adam; Burke-Spolaor, Sarah; Chamberlin, Sydney; Chatterjee, Shami; Christy, Brian; Cordes, James M.; Cornish, Neil J.; Crawford, Fronefield; Thankful Cromartie, H.; Crowter, Kathryn; DeCesar, Megan E.; Demorest, Paul B.; Dolch, Timothy; Ellis, Justin A.; Ferdman, Robert D.; Ferrara, Elizabeth C.; Fonseca, Emmanuel; Garver-Daniels, Nathan; Gentile, Peter A.; Halmrast, Daniel; Huerta, E. A.; Jenet, Fredrick A.; Jessup, Cody; Jones, Glenn; Jones, Megan L.; Kaplan, David L.; Lam, Michael T.; Lazio, T. Joseph W.; Levin, Lina; Lommen, Andrea; Lorimer, Duncan R.; Luo, Jing; Lynch, Ryan S.; Madison, Dustin; Matthews, Allison M.; McLaughlin, Maura A.; McWilliams, Sean T.; Mingarelli, Chiara; Ng, Cherry; Nice, David J.; Pennucci, Timothy T.; Ransom, Scott M.; Ray, Paul S.; Siemens, Xavier; Simon, Joseph; Spiewak, Renée; Stairs, Ingrid H.; Stinebring, Daniel R.; Stovall, Kevin; Swiggum, Joseph K.; Taylor, Stephen R.; Vallisneri, Michele; van Haasteren, Rutger; Vigeland, Sarah J.; Zhu, Weiwei; The NANOGrav Collaboration

    2018-04-01

    We present high-precision timing data over time spans of up to 11 years for 45 millisecond pulsars observed as part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) project, aimed at detecting and characterizing low-frequency gravitational waves. The pulsars were observed with the Arecibo Observatory and/or the Green Bank Telescope at frequencies ranging from 327 MHz to 2.3 GHz. Most pulsars were observed with approximately monthly cadence, and six high-timing-precision pulsars were observed weekly. All were observed at widely separated frequencies at each observing epoch in order to fit for time-variable dispersion delays. We describe our methods for data processing, time-of-arrival (TOA) calculation, and the implementation of a new, automated method for removing outlier TOAs. We fit a timing model for each pulsar that includes spin, astrometric, and (for binary pulsars) orbital parameters; time-variable dispersion delays; and parameters that quantify pulse-profile evolution with frequency. The timing solutions provide three new parallax measurements, two new Shapiro delay measurements, and two new measurements of significant orbital-period variations. We fit models that characterize sources of noise for each pulsar. We find that 11 pulsars show significant red noise, with generally smaller spectral indices than typically measured for non-recycled pulsars, possibly suggesting a different origin. A companion paper uses these data to constrain the strength of the gravitational-wave background.

  5. Single Crystal Piezomotor for Large Stroke, High Precision and Cryogenic Actuations, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — TRS Technologies proposes a novel single crystal piezomotor for large stroke, high precision, and cryogenic actuations with capability of position set-hold with...

  6. Drift chambers for a large-area, high-precision muon spectrometer

    International Nuclear Information System (INIS)

    Alberini, C.; Bari, G.; Cara Romeo, G.; Cifarelli, L.; Del Papa, C.; Iacobucci, G.; Laurenti, G.; Maccarrone, G.; Massam, T.; Motta, F.; Nania, R.; Perotto, E.; Prisco, G.; Willutsky, M.; Basile, M.; Contin, A.; Palmonari, F.; Sartorelli, G.

    1987-01-01

    We have tested two prototypes of high-precision drift chamber for a magnetic muon spectrometer. Results of the tests are presented, with special emphasis on their efficiency and spatial resolution as a function of particle rate. (orig.)

  7. High-precision analogue peak detector for X-ray imaging applications

    OpenAIRE

    Dlugosz, Rafal Tomasz; Iniewski, Kris

    2007-01-01

    A new analogue high-precision peak detector is presented. Owing to its very low power consumption the circuit is particularly well suited for photon energy detection in multichannel receiver integrated circuits used in nuclear medicine.

  8. submitter A High Precision 3D Magnetic Field Scanner for Small to Medium Size Magnets

    CERN Document Server

    Bergsma, F; Garnier, F; Giudici, P A

    2016-01-01

    A bench to measure the magnetic field of small to-medium-sized magnets with high precision was built. It uses a small-sized head with three orthogonal Hall probes, supported on a long pole at continuous movement during measurement. The head is calibrated in three dimensions by rotation over the full solid angle in a special device. From 0 to 2.5 T, the precision is ±0.2 mT in all components. The spatial range is 1 × 1 × 2 m with precision of ±0.02 mm. The bench and its controls are lightweight and easy to transport. The head can penetrate through small apertures and measure as close as 0.5 mm from the surface of a magnet. The bench can scan complicated grids in Cartesian or cylindrical coordinates, steered by a simple text file on an accompanying PC. The raw data is online converted to magnetic units and stored in a text file.

  9. A High-precision Trigonometric Parallax to an Ancient Metal-poor Globular Cluster

    Science.gov (United States)

    Brown, T. M.; Casertano, S.; Strader, J.; Riess, A.; VandenBerg, D. A.; Soderblom, D. R.; Kalirai, J.; Salinas, R.

    2018-03-01

    Using the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST), we have obtained a direct trigonometric parallax for the nearest metal-poor globular cluster, NGC 6397. Although trigonometric parallaxes have been previously measured for many nearby open clusters, this is the first parallax for an ancient metal-poor population—one that is used as a fundamental template in many stellar population studies. This high-precision measurement was enabled by the HST/WFC3 spatial-scanning mode, providing hundreds of astrometric measurements for dozens of stars in the cluster and also for Galactic field stars along the same sightline. We find a parallax of 0.418 ± 0.013 ± 0.018 mas (statistical, systematic), corresponding to a true distance modulus of 11.89 ± 0.07 ± 0.09 mag (2.39 ± 0.07 ± 0.10 kpc). The V luminosity at the stellar main-sequence turnoff implies an absolute cluster age of 13.4 ± 0.7 ± 1.2 Gyr. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs GO-13817, GO-14336, and GO-14773.

  10. Effect of stellar activity on the high precision transit light curve

    Directory of Open Access Journals (Sweden)

    Oshagh, M.

    2015-01-01

    Full Text Available Stellar activity features such as spots and plages can create difficulties in determining planetary parameters through spectroscopic and photometric observations. The overlap of a transiting planet and a stellar spot, for instance, can produce anomalies in the transit light curve that may lead to inaccurate estimation of the transit duration, depth, and timing. Such inaccuracies can affect the precise derivation of the planet’s radius. In this talk we will present the results of a quantitative study on the effects of stellar spots on high precision transit light curves. We show that spot anomalies can lead to the estimate of a planet radius that is 4% smaller than the real value. The effects on the transit duration can also be of the order of 4%, longer or shorter. Depending on the size and distribution of spots, anomalies can also produce transit timing variations with significant amplitudes. For instance, TTVs with signal amplitudes of 200 seconds can be produced by spots as large as the largest sunspot. Finally, we examine the impact of active regions on the transit depth measurements in different wavelengths, in order to probe the impact of this effect on transmission spectroscopy measurements. We show that significant (up to 10% underestimation/overestimation of the planet-to-star radius ratio can be measured, especially in the short wavelength regime.

  11. A simulation of driven reconnection by a high precision MHD code

    International Nuclear Information System (INIS)

    Kusano, Kanya; Ouchi, Yasuo; Hayashi, Takaya; Horiuchi, Ritoku; Watanabe, Kunihiko; Sato, Tetsuya.

    1988-01-01

    A high precision MHD code, which has the fourth-order accuracy for both the spatial and time steps, is developed, and is applied to the simulation studies of two dimensional driven reconnection. It is confirm that the numerical dissipation of this new scheme is much less than that of two-step Lax-Wendroff scheme. The effect of the plasma compressibility on the reconnection dynamics is investigated by means of this high precision code. (author)

  12. High-precision tracking of brownian boomerang colloidal particles confined in quasi two dimensions.

    Science.gov (United States)

    Chakrabarty, Ayan; Wang, Feng; Fan, Chun-Zhen; Sun, Kai; Wei, Qi-Huo

    2013-11-26

    In this article, we present a high-precision image-processing algorithm for tracking the translational and rotational Brownian motion of boomerang-shaped colloidal particles confined in quasi-two-dimensional geometry. By measuring mean square displacements of an immobilized particle, we demonstrate that the positional and angular precision of our imaging and image-processing system can achieve 13 nm and 0.004 rad, respectively. By analyzing computer-simulated images, we demonstrate that the positional and angular accuracies of our image-processing algorithm can achieve 32 nm and 0.006 rad. Because of zero correlations between the displacements in neighboring time intervals, trajectories of different videos of the same particle can be merged into a very long time trajectory, allowing for long-time averaging of different physical variables. We apply this image-processing algorithm to measure the diffusion coefficients of boomerang particles of three different apex angles and discuss the angle dependence of these diffusion coefficients.

  13. High precision spectroscopy of pionic and antiprotonic atoms; Spectroscopie de precision des atomes pioniques et antiprotoniques

    Energy Technology Data Exchange (ETDEWEB)

    El-Khoury, P

    1998-04-15

    The study of exotic atoms, in which an orbiting electron of a normal atom is replaced by a negatively charged particle ({pi}{sup -}, {mu}{sup -}, p, {kappa}{sup -}, {sigma}{sup -},...) may provide information on the orbiting particle and the atomic nucleus, as well as on their interaction. In this work, we were interested in pionic atoms ({pi}{sup -14} N) on the one hand in order to determine the pion mass with high accuracy (4 ppm), and on the other hand in antiprotonic atoms (pp-bar) in order to study the strong nucleon-antinucleon interaction at threshold. In this respect, a high-resolution crystal spectrometer was coupled to a cyclotron trap which provides a high stop density for particles in gas targets at low pressure. Using curved crystals, an extended X-ray source could be imaged onto the detector. Charge-Coupled Devices were used as position sensitive detectors in order to measure the Bragg angle of the transition to a high precision. The use of gas targets resolved the ambiguity owing to the number of K electrons for the value of the pion mass, and, for the first time, strong interaction shift and broadening of the 2p level in antiprotonic hydrogen were measured directly. (author)

  14. High-precision gamma-ray spectroscopy for enhancing production and application of medical isotopes

    Science.gov (United States)

    McCutchan, E. A.; Sonzogni, A. A.; Smith, S. V.; Muench, L.; Nino, M.; Greene, J. P.; Carpenter, M. P.; Zhu, S.; Chillery, T.; Chowdhury, P.; Harding, R.; Lister, C. J.

    2015-10-01

    Nuclear medicine is a field which requires precise decay data for use in planning radionuclide production and in imaging and therapeutic applications. To address deficiencies in decay data, sources of medical isotopes were produced and purified at the Brookhaven Linear Isotope Producer (BLIP) then shipped to Argonne National Laboratory where high-precision, gamma-ray measurements were performed using Gammasphere. New decay schemes for a number of PET isotopes and the impact on dose calculations will be presented. To investigate the production of next-generation theranostic or radiotherapeutic isotopes, cross section measurements with high energy protons have also been explored at BLIP. The 100-200 MeV proton energy regime is relatively unexplored for isotope production, thus offering high discovery potential but at the same time a challenging analysis due to the large number of open channels at these energies. Results of cross sections deduced from Compton-suppressed, coincidence gamma-ray spectroscopy performed at Lowell will be presented, focusing on the production of platinum isotopes by irradiating natural platinum foils with 100 to 200 MeV protons. DOE Isotope Program is acknowledged for funding ST5001030. Work supported by the US DOE under Grant DE-FG02-94ER40848 and Contracts DE-AC02-98CH10946 and DE-AC02-06CH11357.

  15. High precision predictions for near-Earth asteroids: the strange case of (3908) Nyx

    Science.gov (United States)

    Farnocchia, D.; Chesley, S. R.; Tholen, D. J.; Micheli, M.

    2014-08-01

    In November 2004 radar delay measurements of near-Earth asteroid (3908) Nyx obtained at the Arecibo radio telescope turned out to be away from the orbital prediction. We prove that this discrepancy was caused by a poor astrometric treatment and an incomplete dynamical model, which did not account for nongravitational perturbations. To improve the astrometric treatment, we remove known star catalog biases, apply suitable weights to the observations, and use an aggressive outlier rejection scheme. The main issue related to the dynamical model is having not accounted for the Yarkovsky effect. Including the Yarkovsky perturbation in the model makes the orbital prediction and the radar measurements statistically consistent by both reducing the offset and increasing the prediction uncertainty to a more realistic level. This analysis shows the sensitivity of high precision predictions to the astrometric treatment and the Yarkovsky effect. By using the full observational dataset we obtain a detection of the Yarkovsky effect acting on Nyx corresponding to an orbital drift m/year. In turn, we derive constraints on thermal inertia and bulk density. In particular, we find that the bulk density of Nyx is around 1 g/cm, possibly less. To make sure that our results are not corrupted by an asteroid impact or a close approach with a perturbing asteroid not included in our dynamical model, we show that the astrometry provides no convincing evidence of an impulsive variation of Nyx's velocity while crossing the main belt region.

  16. Challenging the Standard Model: High-Precision Comparisons of the Fundamental Properties of Protons and Antiprotons

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    The Baryon Antibaryon Symmetry Experiment (BASE-CERN) at CERN’s antiproton decelerator facility is aiming at high-precision comparisons of the fundamental properties of protons and antiprotons, such as charge-to-mass ratios, magnetic moments and lifetimes. Such experiments provide sensitive tests of the fundamental charge-parity-time invariance in the baryon sector. BASE was approved in 2013 and has measured since then, utilizing single-particle multi-Penning-trap techniques, the antiproton-to-proton charge-to-mass ratio with a fractional precision of 69 p.p.t. [1], as well as the antiproton magnetic moment with fractional precisions of 0.8 p.p.m. and 1.5 p.p.b., respectively [2]. At our matter companion experiment BASE-Mainz, we have performed proton magnetic moment measurements with fractional uncertainties of 3.3 p.p.b. [3] and 0.3 p.p.b. [4]. By combining the data of both experiments we provide a baryon-magnetic-moment based CPT test gpbar/gp = 1.000 000 000 2(15), which improves the uncertainty of p...

  17. Test of feasibility of a novel high precision test of time reversal invariance

    International Nuclear Information System (INIS)

    Samuel, Deepak

    2007-01-01

    The first results of a feasibility test of a novel high precision test of time reversal invariance are reported. The Time Reversal Invariance test at COSY (TRIC) was planned to measure the time reversal violating observable A y,xz with an accuracy of 10 -6 in proton-deuteron (p-d) scattering. A novel technique for measuring total cross sections is introduced and the achievable precision of this measuring technique is tested. The correlation coefficient A y,y in p-d scattering fakes a time-reversal violating effect. This work reports the feasibility test of the novel method in the measurement of A y,y in p-p scattering. The first step in the experimental design was the development of a hard real-time data acquisition system. To meet stringent latency requirements, the capabilities of Windows XP had to be augmented with a real-time subsystem. The remote control feature of the data acquisition enables users to operate it from any place via an internet connection. The data acquisition proved its reliability in several beam times without any failures. The analysis of the data showed the presence of 1/f noise which substantially limits the quality of our measurements. The origin of 1/f noise was traced and found to be the Barkhausen noise from the ferrite core of the beam current transformer (BCT). A global weighted fitting technique based on a modified Wiener-Khinchin method was developed and used to suppress the influence of 1/f noise, which increased the error bar of the results by a factor 3. This is the only deviation from our expectations. The results are presented and discussed. (orig.)

  18. Test of feasibility of a novel high precision test of time reversal invariance

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Deepak

    2007-07-01

    The first results of a feasibility test of a novel high precision test of time reversal invariance are reported. The Time Reversal Invariance test at COSY (TRIC) was planned to measure the time reversal violating observable A{sub y,xz} with an accuracy of 10{sup -6} in proton-deuteron (p-d) scattering. A novel technique for measuring total cross sections is introduced and the achievable precision of this measuring technique is tested. The correlation coefficient A{sub y,y} in p-d scattering fakes a time-reversal violating effect. This work reports the feasibility test of the novel method in the measurement of A{sub y,y} in p-p scattering. The first step in the experimental design was the development of a hard real-time data acquisition system. To meet stringent latency requirements, the capabilities of Windows XP had to be augmented with a real-time subsystem. The remote control feature of the data acquisition enables users to operate it from any place via an internet connection. The data acquisition proved its reliability in several beam times without any failures. The analysis of the data showed the presence of 1/f noise which substantially limits the quality of our measurements. The origin of 1/f noise was traced and found to be the Barkhausen noise from the ferrite core of the beam current transformer (BCT). A global weighted fitting technique based on a modified Wiener-Khinchin method was developed and used to suppress the influence of 1/f noise, which increased the error bar of the results by a factor 3. This is the only deviation from our expectations. The results are presented and discussed. (orig.)

  19. An evaluation of a single-step extraction chromatography separation method for Sm-Nd isotope analysis of micro-samples of silicate rocks by high-sensitivity thermal ionization mass spectrometry

    International Nuclear Information System (INIS)

    Li Chaofeng; Li Xianhua; Li Qiuli; Guo Jinghui; Li Xianghui; Liu Tao

    2011-01-01

    Graphical abstract: Distribution curve of all eluting fractions for a BCR-2 (1-2-3.5-7 mg) on LN column using HCl and HF as eluting reagent. Highlights: → This analytical protocol affords a simple and rapid analysis for Sm and Nd isotope in minor rock samples. → The single-step separation method exhibits satisfactory separation effect for complex silicate samples. → Corrected 143 Nd/ 144 Nd data show excellent accuracy even if the 140 Ce 16 O + / 144 Nd 16 O + ratio reached to 0.03. - Abstract: A single-step separation scheme is presented for Sm-Nd radiogenic isotope system on very small samples (1-3 mg) of silicate rock. This method is based on Eichrom LN Spec chromatographic material and affords a straightforward separation of Sm-Nd from complex matrix with good purity and satisfactory blank levels, suitable for thermal ionization mass spectrometry (TIMS). This technique, characterized by high efficiency (single-step Sm-Nd separation) and high sensitivity (TIMS on NdO + ion beam), is able to process rapidly (3-4 h), with low procedure blanks ( 143 Nd/ 144 Nd ratios and Sm-Nd concentrations are presented for eleven international silicate rock reference materials, spanning a wide range of Sm-Nd contents and bulk compositions. The analytical results show a good agreement with recommended values within ±0.004% for the 143 Nd/ 144 Nd isotopic ratio and ±2% for Sm-Nd quantification at the 95% confidence level. It is noted that the uncertainty of this method is about 3 times larger than typical precision achievable with two-stage full separation followed by state-of-the-art conventional TIMS using Nd + ion beams which require much larger amounts of Nd. Hence, our single-step separation followed by NdO + ion beam technique is preferred to the analysis for microsamples.

  20. High-precision predictions for the light CP-even Higgs boson mass of the MSSM

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, T.; Hollik, W. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Heinemeyer, S. [Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Rzehak, H. [Freiburg Univ. (Germany). Physikalisches Inst.; Weiglein, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2014-03-15

    For the interpretation of the signal discovered in the Higgs searches at the LHC it will be crucial in particular to discriminate between the minimal Higgs sector realised in the Standard Model (SM) and its most commonly studied extension, the Minimal Supersymmetric SM (MSSM). The measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role in this context. In the MSSM the mass of the light CP-even Higgs boson, M{sub h}, can directly be predicted from the other parameters of the model. The accuracy of this prediction should at least match the one of the experimental result. The relatively high mass value of about 126 GeV has led to many investigations where the scalar top quarks are in the multi-TeV range. We improve the prediction for M{sub h} in the MSSM by combining the existing fixed-order result, comprising the full one-loop and leading and subleading two-loop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a high-precision prediction for the mass of the light CP-even Higgs boson in the MSSM is possible all the way up to the multi-TeV region of the relevant supersymmetric particles. The results are included in the code FeynHiggs.

  1. A high-precision sampling scheme to assess persistence and transport characteristics of micropollutants in rivers.

    Science.gov (United States)

    Schwientek, Marc; Guillet, Gaëlle; Rügner, Hermann; Kuch, Bertram; Grathwohl, Peter

    2016-01-01

    Increasing numbers of organic micropollutants are emitted into rivers via municipal wastewaters. Due to their persistence many pollutants pass wastewater treatment plants without substantial removal. Transport and fate of pollutants in receiving waters and export to downstream ecosystems is not well understood. In particular, a better knowledge of processes governing their environmental behavior is needed. Although a lot of data are available concerning the ubiquitous presence of micropollutants in rivers, accurate data on transport and removal rates are lacking. In this paper, a mass balance approach is presented, which is based on the Lagrangian sampling scheme, but extended to account for precise transport velocities and mixing along river stretches. The calculated mass balances allow accurate quantification of pollutants' reactivity along river segments. This is demonstrated for representative members of important groups of micropollutants, e.g. pharmaceuticals, musk fragrances, flame retardants, and pesticides. A model-aided analysis of the measured data series gives insight into the temporal dynamics of removal processes. The occurrence of different removal mechanisms such as photooxidation, microbial degradation, and volatilization is discussed. The results demonstrate, that removal processes are highly variable in time and space and this has to be considered for future studies. The high precision sampling scheme presented could be a powerful tool for quantifying removal processes under different boundary conditions and in river segments with contrasting properties. Copyright © 2015. Published by Elsevier B.V.

  2. Maintaining high precision of isotope ratio analysis over extended periods of time.

    Science.gov (United States)

    Brand, Willi A

    2009-06-01

    Stable isotope ratios are reliable and long lasting process tracers. In order to compare data from different locations or different sampling times at a high level of precision, a measurement strategy must include reliable traceability to an international stable isotope scale via a reference material (RM). Since these international RMs are available in low quantities only, we have developed our own analysis schemes involving laboratory working RM. In addition, quality assurance RMs are used to control the long-term performance of the delta-value assignments. The analysis schemes allow the construction of quality assurance performance charts over years of operation. In this contribution, the performance of three typical techniques established in IsoLab at the MPI-BGC in Jena is discussed. The techniques are (1) isotope ratio mass spectrometry with an elemental analyser for delta(15)N and delta(13)C analysis of bulk (organic) material, (2) high precision delta(13)C and delta(18)O analysis of CO(2) in clean-air samples, and (3) stable isotope analysis of water samples using a high-temperature reaction with carbon. In addition, reference strategies on a laser ablation system for high spatial resolution delta(13)C analysis in tree rings is exemplified briefly.

  3. Development and simulation of microfluidic Wheatstone bridge for high-precision sensor

    International Nuclear Information System (INIS)

    Shipulya, N D; Konakov, S A; Krzhizhanovskaya, V V

    2016-01-01

    In this work we present the results of analytical modeling and 3D computer simulation of microfluidic Wheatstone bridge, which is used for high-accuracy measurements and precision instruments. We propose and simulate a new method of a bridge balancing process by changing the microchannel geometry. This process is based on the “etching in microchannel” technology we developed earlier (doi:10.1088/1742-6596/681/1/012035). Our method ensures a precise control of the flow rate and flow direction in the bridge microchannel. The advantage of our approach is the ability to work without any control valves and other active electronic systems, which are usually used for bridge balancing. The geometrical configuration of microchannels was selected based on the analytical estimations. A detailed 3D numerical model was based on Navier-Stokes equations for a laminar fluid flow at low Reynolds numbers. We investigated the behavior of the Wheatstone bridge under different process conditions; found a relation between the channel resistance and flow rate through the bridge; and calculated the pressure drop across the system under different total flow rates and viscosities. Finally, we describe a high-precision microfluidic pressure sensor that employs the Wheatstone bridge and discuss other applications in complex precision microfluidic systems. (paper)

  4. HIGH-PRECISION PREDICTIONS FOR THE ACOUSTIC SCALE IN THE NONLINEAR REGIME

    International Nuclear Information System (INIS)

    Seo, Hee-Jong; Eckel, Jonathan; Eisenstein, Daniel J.; Mehta, Kushal; Metchnik, Marc; Pinto, Phillip; Xu Xiaoying; Padmanabhan, Nikhil; Takahashi, Ryuichi; White, Martin

    2010-01-01

    We measure shifts of the acoustic scale due to nonlinear growth and redshift distortions to a high precision using a very large volume of high-force-resolution simulations. We compare results from various sets of simulations that differ in their force, volume, and mass resolution. We find a consistency within 1.5σ for shift values from different simulations and derive shift α(z) - 1 = (0.300 ± 0.015) %[D(z)/D(0)] 2 using our fiducial set. We find a strong correlation with a non-unity slope between shifts in real space and in redshift space and a weak correlation between the initial redshift and low redshift. Density-field reconstruction not only removes the mean shifts and reduces errors on the mean, but also tightens the correlations. After reconstruction, we recover a slope of near unity for the correlation between the real and redshift space and restore a strong correlation between the initial and the low redshifts. We derive propagators and mode-coupling terms from our N-body simulations and compare with the Zel'dovich approximation and the shifts measured from the χ 2 fitting, respectively. We interpret the propagator and the mode-coupling term of a nonlinear density field in the context of an average and a dispersion of its complex Fourier coefficients relative to those of the linear density field; from these two terms, we derive a signal-to-noise ratio of the acoustic peak measurement. We attempt to improve our reconstruction method by implementing 2LPT and iterative operations, but we obtain little improvement. The Fisher matrix estimates of uncertainty in the acoustic scale is tested using 5000 h -3 Gpc 3 of cosmological Particle-Mesh simulations from Takahashi et al. At an expected sample variance level of 1%, the agreement between the Fisher matrix estimates based on Seo and Eisenstein and the N-body results is better than 10%.

  5. A near infrared laser frequency comb for high precision Doppler planet surveys

    Directory of Open Access Journals (Sweden)

    Bally J.

    2011-07-01

    Full Text Available Perhaps the most exciting area of astronomical research today is the study of exoplanets and exoplanetary systems, engaging the imagination not just of the astronomical community, but of the general population. Astronomical instrumentation has matured to the level where it is possible to detect terrestrial planets orbiting distant stars via radial velocity (RV measurements, with the most stable visible light spectrographs reporting RV results the order of 1 m/s. This, however, is an order of magnitude away from the precision needed to detect an Earth analog orbiting a star such as our sun, the Holy Grail of these efforts. By performing these observations in near infrared (NIR there is the potential to simplify the search for distant terrestrial planets by studying cooler, less massive, much more numerous class M stars, with a tighter habitable zone and correspondingly larger RV signal. This NIR advantage is undone by the lack of a suitable high precision, high stability wavelength standard, limiting NIR RV measurements to tens or hundreds of m/s [1, 2]. With the improved spectroscopic precision provided by a laser frequency comb based wavelength reference producing a set of bright, densely and uniformly spaced lines, it will be possible to achieve up to two orders of magnitude improvement in RV precision, limited only by the precision and sensitivity of existing spectrographs, enabling the observation of Earth analogs through RV measurements. We discuss the laser frequency comb as an astronomical wavelength reference, and describe progress towards a near infrared laser frequency comb at the National Institute of Standards and Technology and at the University of Colorado where we are operating a laser frequency comb suitable for use with a high resolution H band astronomical spectrograph.

  6. An Ultra-low Frequency Modal Testing Suspension System for High Precision Air Pressure Control

    Directory of Open Access Journals (Sweden)

    Qiaoling YUAN

    2014-05-01

    Full Text Available As a resolution for air pressure control challenges in ultra-low frequency modal testing suspension systems, an incremental PID control algorithm with dead band is applied to achieve high-precision pressure control. We also develop a set of independent hardware and software systems for high-precision pressure control solutions. Taking control system versatility, scalability, reliability, and other aspects into considerations, a two-level communication employing Ethernet and CAN bus, is adopted to complete such tasks as data exchange between the IPC, the main board and the control board ,and the pressure control. Furthermore, we build a single set of ultra-low frequency modal testing suspension system and complete pressure control experiments, which achieve the desired results and thus confirm that the high-precision pressure control subsystem is reasonable and reliable.

  7. A High Precision Laser-Based Autofocus Method Using Biased Image Plane for Microscopy

    Directory of Open Access Journals (Sweden)

    Chao-Chen Gu

    2018-01-01

    Full Text Available This study designs and accomplishes a high precision and robust laser-based autofocusing system, in which a biased image plane is applied. In accordance to the designed optics, a cluster-based circle fitting algorithm is proposed to calculate the radius of the detecting spot from the reflected laser beam as an essential factor to obtain the defocus value. The experiment conduct on the experiment device achieved novel performance of high precision and robustness. Furthermore, the low demand of assembly accuracy makes the proposed method a low-cost and realizable solution for autofocusing technique.

  8. High precision NC lathe feeding system rigid-flexible coupling model reduction technology

    Science.gov (United States)

    Xuan, He; Hua, Qingsong; Cheng, Lianjun; Zhang, Hongxin; Zhao, Qinghai; Mao, Xinkai

    2017-08-01

    This paper proposes the use of dynamic substructure method of reduction of order to achieve effective reduction of feed system for high precision NC lathe feeding system rigid-flexible coupling model, namely the use of ADAMS to establish the rigid flexible coupling simulation model of high precision NC lathe, and then the vibration simulation of the period by using the FD 3D damper is very effective for feed system of bolt connection reduction of multi degree of freedom model. The vibration simulation calculation is more accurate, more quickly.

  9. Selecting Pixels for High-Precision Photometry in the Kepler Mission

    Science.gov (United States)

    Bryson, Steve; Jenkins, J.; Caldwell, D.; Koch, D.; Borucki, W.

    2007-12-01

    The Kepler Mission is designed to discover and characterize the frequency of Earth-size planets in the habitable zone of solar-like stars by observing 100,000 main-sequence stars in a 100 square degree field of view (FOV). Kepler's transit detection method uses a long photometric time series for each target star. Each data point is created by summing several pixels.The data are co-added and stored at a 30 minute cadence that is stored for monthly downlink. Memory and bandwidth constraints prevent the storage of all 95 million pixels in the photometer, so pixels of interest are assigned to each target. We describe the automated method by which each transit target is assigned a set of pixels that are optimal for high precision photometry. This method relies on synthetic images based on the Kepler input catalog combined with a direct measurement of the Kepler systempoint spread function. We cover the PSF measurement process, the rendering of the synthetic image, and the use of the synthetic image to determine the contribution of each pixel to a target's signal-to-noise ratio. The optimal pixels for a target are defined as those pixels which maximize that target's signal-to-noise ratio. Our method includes models of the noise associated with pixel response variations and for spacecraft motion. We describe the process that is used to identify appropriate pixels for modeling the background as well as pixel management, including the specification of pixels for non-transit targets. Funding for this mission provided by NASA's Discovery Program Office, SMD.

  10. P2. A fused silica Cherenkov detector for the high precision determination of the weak mixing angle

    Energy Technology Data Exchange (ETDEWEB)

    Gerz, Kathrin; Becker, Dominik; Jennewein, Thomas; Baunack, Sebastian [Johannes Gutenberg Universitaet Mainz (Germany); Kumar, Krishna [Department of Physics and Astronomy, Stony Brook University, Stony Brook (United States); Maas, Frank [Johannes Gutenberg Universitaet Mainz (Germany); Helmholtz Institut Mainz (Germany)

    2016-07-01

    The weak mixing angle is a central parameter of the standard model and its high precision determination is tantamount to probing for new physics effects. The P2 experiment at the MESA accelerator in Mainz will perform such a measurement of the weak mixing angle via parity violating electron-proton scattering. We aim to determine sin{sup 2}(Θ{sub W}) to a relative precision of 0.13%. Since the weak charge of the proton is small compared to its electric charge, the measurable asymmetry is only 33 ppb, requiring a challenging measurement to a precision of only 0.44 ppb. In order to achieve this precision we need to collect very high statistics and carefully minimize interfering effects like apparatus induced false asymmetries. We present the status of the development of an integrating fused-silica Cherenkov detector, which is suitable for a high precision and high intensity experiment like P2. The contribution will focus on the investigation of the detector's response to incoming signal and background particles both by simulations and by beam tests at the MAMI accelerator.

  11. Reassembling and testing of a high-precision heat capacity drop calorimeter. Heat capacity of some polyphenyls at T = 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Luis M.N.B.F., E-mail: lbsantos@fc.up.pt [Centro de Investigacao em Quimica, Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Rocha, Marisa A.A.; Rodrigues, Ana S.M.C. [Centro de Investigacao em Quimica, Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Stejfa, Vojtech; Fulem, Michal [Department of Physical Chemistry, Institute of Chemical Technology, Technicka 5, CZ-166 28 Prague 6 (Czech Republic); Bastos, Margarida [Centro de Investigacao em Quimica, Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal)

    2011-12-15

    Graphical abstract: Highlights: > We present the reassembling, improvement and testing of a high-precision C{sub p} drop calorimeter. > The apparatus was tested, using benzoic acid and hexafluorobenzene. > The high sensitivity of the apparatus is comparable to the one obtained in adiabatic calorimetry. > Heat capacities at T = 298.15 K of some polyphenyls were measured. > Subtle heat capacity differences among position isomers (ortho, meta, para) were detected. - Abstract: The description of the reassembling and testing of a twin heat conduction, high-precision, drop microcalorimeter for the measurement of heat capacities of small samples are presented. The apparatus, originally developed and used at the Thermochemistry Laboratory, Lund, Sweden, has now been reassembled and modernized, with changes being made as regarding temperature sensors, electronics and data acquisition system. The apparatus was thereafter thoroughly tested, using benzoic acid and hexafluorobenzene as test substances. The accuracy of the C{sub p,m}{sup 0} (298.15 K) data obtained with this apparatus is comparable to that achieved by high-precision adiabatic calorimetry. Here we also present the results of heat capacity measurements on of some polyphenyls (1,2,3-triphenylbenzene, 1,3,5-triphenylbenzene, p-terphenyl, m-terphenyl, o-terphenyl, p-quaterphenyl) at T = 298.15 K, measured with the renewed high precision heat capacity drop calorimeter system. The high resolution and accuracy of the obtained heat capacity data enabled differentiation among the ortho-, meta-, and para-phenyl isomers.

  12. High-precision GPS autonomous platforms for sea ice dynamics and physical oceanography

    Science.gov (United States)

    Elosegui, P.; Wilkinson, J.; Olsson, M.; Rodwell, S.; James, A.; Hagan, B.; Hwang, B.; Forsberg, R.; Gerdes, R.; Johannessen, J.; Wadhams, P.; Nettles, M.; Padman, L.

    2012-12-01

    Project "Arctic Ocean sea ice and ocean circulation using satellite methods" (SATICE), is the first high-rate, high-precision, continuous GPS positioning experiment on sea ice in the Arctic Ocean. The SATICE systems collect continuous, dual-frequency carrier-phase GPS data while drifting on sea ice. Additional geophysical measurements also collected include ocean water pressure, ocean surface salinity, atmospheric pressure, snow-depth, air-ice-ocean temperature profiles, photographic imagery, and others, enabling sea ice drift, freeboard, weather, ice mass balance, and sea-level height determination. Relatively large volumes of data from each buoy are streamed over a satellite link to a central computer on the Internet in near real time, where they are processed to estimate the time-varying buoy positions. SATICE system obtains continuous GPS data at sub-minute intervals with a positioning precision of a few centimetres in all three dimensions. Although monitoring of sea ice motions goes back to the early days of satellite observations, these autonomous platforms bring out a level of spatio-temporal detail that has never been seen before, especially in the vertical axis. These high-resolution data allows us to address new polar science questions and challenge our present understanding of both sea ice dynamics and Arctic oceanography. We will describe the technology behind this new autonomous platform, which could also be adapted to other applications that require high resolution positioning information with sustained operations and observations in the polar marine environment, and present results pertaining to sea ice dynamics and physical oceanography.

  13. Predicting the Maximum Dynamic Strength in Bench Press: The High Precision of the Bar Velocity Approach.

    Science.gov (United States)

    Loturco, Irineu; Kobal, Ronaldo; Moraes, José E; Kitamura, Katia; Cal Abad, César C; Pereira, Lucas A; Nakamura, Fábio Y

    2017-04-01

    Loturco, I, Kobal, R, Moraes, JE, Kitamura, K, Cal Abad, CC, Pereira, LA, and Nakamura, FY. Predicting the maximum dynamic strength in bench press: the high precision of the bar velocity approach. J Strength Cond Res 31(4): 1127-1131, 2017-The aim of this study was to determine the force-velocity relationship and test the possibility of determining the 1 repetition maximum (1RM) in "free weight" and Smith machine bench presses. Thirty-six male top-level athletes from 3 different sports were submitted to a standardized 1RM bench press assessment (free weight or Smith machine, in randomized order), following standard procedures encompassing lifts performed at 40-100% of 1RM. The mean propulsive velocity (MPV) was measured in all attempts. A linear regression was performed to establish the relationships between bar velocities and 1RM percentages. The actual and predicted 1RM for each exercise were compared using a paired t-test. Although the Smith machine 1RM was higher (10% difference) than the free weight 1RM, in both cases the actual and predicted values did not differ. In addition, the linear relationship between MPV and percentage of 1RM (coefficient of determination ≥95%) allow determination of training intensity based on the bar velocity. The linear relationships between the MPVs and the relative percentages of 1RM throughout the entire range of loads enable coaches to use the MPV to accurately monitor their athletes on a daily basis and accurately determine their actual 1RM without the need to perform standard maximum dynamic strength assessments.

  14. High-precision genetic mapping of behavioral traits in the diversity outbred mouse population

    Science.gov (United States)

    Logan, R W; Robledo, R F; Recla, J M; Philip, V M; Bubier, J A; Jay, J J; Harwood, C; Wilcox, T; Gatti, D M; Bult, C J; Churchill, G A; Chesler, E J

    2013-01-01

    Historically our ability to identify genetic variants underlying complex behavioral traits in mice has been limited by low mapping resolution of conventional mouse crosses. The newly developed Diversity Outbred (DO) population promises to deliver improved resolution that will circumvent costly fine-mapping studies. The DO is derived from the same founder strains as the Collaborative Cross (CC), including three wild-derived strains. Thus the DO provides more allelic diversity and greater potential for discovery compared to crosses involving standard mouse strains. We have characterized 283 male and female DO mice using open-field, light–dark box, tail-suspension and visual-cliff avoidance tests to generate 38 behavioral measures. We identified several quantitative trait loci (QTL) for these traits with support intervals ranging from 1 to 3 Mb in size. These intervals contain relatively few genes (ranging from 5 to 96). For a majority of QTL, using the founder allelic effects together with whole genome sequence data, we could further narrow the positional candidates. Several QTL replicate previously published loci. Novel loci were also identified for anxiety- and activity-related traits. Half of the QTLs are associated with wild-derived alleles, confirming the value to behavioral genetics of added genetic diversity in the DO. In the presence of wild-alleles we sometimes observe behaviors that are qualitatively different from the expected response. Our results demonstrate that high-precision mapping of behavioral traits can be achieved with moderate numbers of DO animals, representing a significant advance in our ability to leverage the mouse as a tool for behavioral genetics PMID:23433259

  15. High precision wavefront control in point spread function engineering for single emitter localization

    Science.gov (United States)

    Siemons, M.; Hulleman, C. N.; Thorsen, R. Ø.; Smith, C. S.; Stallinga, S.

    2018-04-01

    Point Spread Function (PSF) engineering is used in single emitter localization to measure the emitter position in 3D and possibly other parameters such as the emission color or dipole orientation as well. Advanced PSF models such as spline fits to experimental PSFs or the vectorial PSF model can be used in the corresponding localization algorithms in order to model the intricate spot shape and deformations correctly. The complexity of the optical architecture and fit model makes PSF engineering approaches particularly sensitive to optical aberrations. Here, we present a calibration and alignment protocol for fluorescence microscopes equipped with a spatial light modulator (SLM) with the goal of establishing a wavefront error well below the diffraction limit for optimum application of complex engineered PSFs. We achieve high-precision wavefront control, to a level below 20 m$\\lambda$ wavefront aberration over a 30 minute time window after the calibration procedure, using a separate light path for calibrating the pixel-to-pixel variations of the SLM, and alignment of the SLM with respect to the optical axis and Fourier plane within 3 $\\mu$m ($x/y$) and 100 $\\mu$m ($z$) error. Aberrations are retrieved from a fit of the vectorial PSF model to a bead $z$-stack and compensated with a residual wavefront error comparable to the error of the SLM calibration step. This well-calibrated and corrected setup makes it possible to create complex `3D+$\\lambda$' PSFs that fit very well to the vectorial PSF model. Proof-of-principle bead experiments show precisions below 10~nm in $x$, $y$, and $\\lambda$, and below 20~nm in $z$ over an axial range of 1 $\\mu$m with 2000 signal photons and 12 background photons.

  16. MiniDSS: a low-power and high-precision miniaturized digital sun sensor

    NARCIS (Netherlands)

    Boer, B.M. de; Durkut, M.; Laan, E.; Hakkesteegt, H.; Theuwissen, A.; Xie, N.; Leijtens, J.L.; Urquijo, E.; Bruins, P.

    2012-01-01

    A high-precision and low-power miniaturized digital sun sensor has been developed at TNO. The single-chip sun sensor comprises an application specific integrated circuit (ASIC) on which an active pixel sensor (APS), read-out and processing circuitry as well as communication circuitry are combined.

  17. Classification of LIDAR Data for Generating a High-Precision Roadway Map

    Science.gov (United States)

    Jeong, J.; Lee, I.

    2016-06-01

    Generating of a highly precise map grows up with development of autonomous driving vehicles. The highly precise map includes a precision of centimetres level unlike an existing commercial map with the precision of meters level. It is important to understand road environments and make a decision for autonomous driving since a robust localization is one of the critical challenges for the autonomous driving car. The one of source data is from a Lidar because it provides highly dense point cloud data with three dimensional position, intensities and ranges from the sensor to target. In this paper, we focus on how to segment point cloud data from a Lidar on a vehicle and classify objects on the road for the highly precise map. In particular, we propose the combination with a feature descriptor and a classification algorithm in machine learning. Objects can be distinguish by geometrical features based on a surface normal of each point. To achieve correct classification using limited point cloud data sets, a Support Vector Machine algorithm in machine learning are used. Final step is to evaluate accuracies of obtained results by comparing them to reference data The results show sufficient accuracy and it will be utilized to generate a highly precise road map.

  18. CLASSIFICATION OF LIDAR DATA FOR GENERATING A HIGH-PRECISION ROADWAY MAP

    Directory of Open Access Journals (Sweden)

    J. Jeong

    2016-06-01

    Full Text Available Generating of a highly precise map grows up with development of autonomous driving vehicles. The highly precise map includes a precision of centimetres level unlike an existing commercial map with the precision of meters level. It is important to understand road environments and make a decision for autonomous driving since a robust localization is one of the critical challenges for the autonomous driving car. The one of source data is from a Lidar because it provides highly dense point cloud data with three dimensional position, intensities and ranges from the sensor to target. In this paper, we focus on how to segment point cloud data from a Lidar on a vehicle and classify objects on the road for the highly precise map. In particular, we propose the combination with a feature descriptor and a classification algorithm in machine learning. Objects can be distinguish by geometrical features based on a surface normal of each point. To achieve correct classification using limited point cloud data sets, a Support Vector Machine algorithm in machine learning are used. Final step is to evaluate accuracies of obtained results by comparing them to reference data The results show sufficient accuracy and it will be utilized to generate a highly precise road map.

  19. High-precision photometry by telescope defocusing - I. The transiting planetary system WASP-5

    DEFF Research Database (Denmark)

    Southworth, J.; Hinse, T. C.; Jørgensen, U. G.

    2009-01-01

    We present high-precision photometry of two transit events of the extrasolar planetary system WASP-5, obtained with the Danish 1.54-m telescope at European Southern Obseratory La Silla. In order to minimize both random and flat-fielding errors, we defocused the telescope so its point spread...

  20. High precision locating control system based on VCM for Talbot lithography

    Science.gov (United States)

    Yao, Jingwei; Zhao, Lixin; Deng, Qian; Hu, Song

    2016-10-01

    Aiming at the high precision and efficiency requirements of Z-direction locating in Talbot lithography, a control system based on Voice Coil Motor (VCM) was designed. In this paper, we built a math model of VCM and its moving characteristic was analyzed. A double-closed loop control strategy including position loop and current loop were accomplished. The current loop was implemented by driver, in order to achieve the rapid follow of the system current. The position loop was completed by the digital signal processor (DSP) and the position feedback was achieved by high precision linear scales. Feed forward control and position feedback Proportion Integration Differentiation (PID) control were applied in order to compensate for dynamic lag and improve the response speed of the system. And the high precision and efficiency of the system were verified by simulation and experiments. The results demonstrated that the performance of Z-direction gantry was obviously improved, having high precision, quick responses, strong real-time and easily to expend for higher precision.

  1. Self-tuning in master-slave synchronization of high-precision stage systems

    NARCIS (Netherlands)

    Heertjes, M.F.; Temizer, B.; Schneiders, M.G.E.

    2013-01-01

    For synchronization of high-precision stage systems, in particular the synchronization between a wafer and a reticle stage system of a wafer scanner, a master–slave controller design is presented. The design consists of a synchronization controller based on FIR filters and a data-driven self-tuning

  2. Achievement report for fiscal 1999 on research and development of technologies for medical welfare equipment. Ultra high-speed/high-precision MRI system for brain function measurement; 1999 nendo iryo fukushi kiki gijutsu kenkyu kaihatsu seika hokokusho. Chokosoku/koseido nokino keisoku MRI system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    A generator of various stimuli is completed, capable of generating light, acoustics, odor, taste, temperature, and vibration, and the harmful effect of its stimulus providing unit on the uniformity of MRI (magnetic resonance imaging) magnetic field is kept at 0.2ppm or less. A single or multiple stimuli are simultaneously generated according to the control program, and they may be set to synchronize with heartbeat or breathing. A light stimulus providing unit is also built, equipped with a line-of-sight detector for the observation of eye movement to occur in response to the light stimulus. Using this unit, the line of sight and the pupil diameter are determined at 60Hz. An experimental MRI unit (maximum spatial resolution: 0.5mm times 0.5mm; activated region positioning error: {+-}2mm or less) is built, and improved. The input/output terminals are modified of an experimental QD4Ch coil for clinical evaluation, and this results in a 1.5 times increase in sensitivity. A brain function image data processing program is applied to the measurement of brain functions, which enables the isolating of the region of activated brain functions. Various stimuli are applied to the subjects in compliance with a planned stimulation paradigm, and a success is attained in the measurement of brain functions by measuring changes in magnetism in blood hemoglobin due to local activation in the brain. (NEDO)

  3. Mats and LaSpec: High-precision experiments using ion traps and lasers at Fair

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D.; Lallena, A.M.; Blaum, K.; Bohm, C.; Cakirli, R.B.; Crespo Lopez-Urrutia, J.R.; Eliseev, S.; Ketelaer, J.; Kreim, M.S.; Kowalska, M.; Litvinov, Y.A.; Nagy, S.; Neidherr, D.; Repp, J.; Roux, C.; Schabinger, B.; Ullrich, J.; Nortershauser, W.; Eberhardt, K.; Geppert, C.; Kramer, J.; Krieger, A.; Sanchez, R.; Ahammed, M.; Das, P.; Ray, A.; Algora, A.; Rubio, B.; Tain, J.L.; Audi, G.; Lunney, D.; Naimi, S.; Aysto, J.; Jokinen, A.; Kolhinen, V.; Moore, I.; Beck, D.; Block, M.; Geissel, H.; Heinz, S.; Herfurth, F.; Litvinov, Y.A.; Minaya-Ramirez, E.; Plab, W.R.; Quint, W.; Scheidenberger, C.; Winkler, M.; Bender, M.; Billowes, J.; Campbell, P.; Flanagan, K.T.; Schwarz, S.; Bollen, G.; Ferrer, R.; George, S.; Kester, O.; Brodeur, M.; Brunner, T.; Delheij, P.; Dilling, J.; Ettenauer, S.; Lapierre, A.; Bushaw, B.A.; Cano-Ott, D.; Martinez, T.; Cortes, G.; Gomez-Hornillos, M.B.; Dax, A.; Herlert, A.; Yordanov, D.; De, A.; Dickel, T.; Geissel, H.; Jesch, C.; Kuhl, T.; Petrick, M.; PlaB, W.R.; Scheidenberger, C.; Garcia-Ramos, J.E.; Gartzke, E.; Habs, D.; Szerypo, J.; Thirolf, P.G.; Weber, C.; Gusev, Y.; Nesterenko, D.; Novikov, Y.N.; Popov, A.; Seliverstov, M.; Vasiliev, A.; Vorobjev, G.; Heenen, P.H.; Marx, G.; Schweikhard, L.; Ziegler, F.; Hobein, M.; Schuch, R.; Solders, A.; Suhonen, M.; Huber, G.; Wendt, K.; Huyse, M.; Koudriavtsev, I.; Neyens, G.; Van Duppen, P.; Le Blanc, F.; Matos, M.; Reinhard, P.G.; Schneider, D.

    2010-05-15

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. With MATS (Precision Measurements of very short-lived nuclei using an Advanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10{sup -9} can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. Decay studies in ion traps will become possible with MATS. Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The accuracy of laser-spectroscopic-determined nuclear properties is very high while requirements concerning production rates are moderate. This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy. Since MATS and LaSpec require high-quality low

  4. Mats and LaSpec: High-precision experiments using ion traps and lasers at Fair

    International Nuclear Information System (INIS)

    Rodriguez, D.; Lallena, A.M.; Blaum, K.; Bohm, C.; Cakirli, R.B.; Crespo Lopez-Urrutia, J.R.; Eliseev, S.; Ketelaer, J.; Kreim, M.S.; Kowalska, M.; Litvinov, Y.A.; Nagy, S.; Neidherr, D.; Repp, J.; Roux, C.; Schabinger, B.; Ullrich, J.; Nortershauser, W.; Eberhardt, K.; Geppert, C.; Kramer, J.; Krieger, A.; Sanchez, R.; Ahammed, M.; Das, P.; Ray, A.; Algora, A.; Rubio, B.; Tain, J.L.; Audi, G.; Lunney, D.; Naimi, S.; Aysto, J.; Jokinen, A.; Kolhinen, V.; Moore, I.; Beck, D.; Block, M.; Geissel, H.; Heinz, S.; Herfurth, F.; Litvinov, Y.A.; Minaya-Ramirez, E.; Plab, W.R.; Quint, W.; Scheidenberger, C.; Winkler, M.; Bender, M.; Billowes, J.; Campbell, P.; Flanagan, K.T.; Schwarz, S.; Bollen, G.; Ferrer, R.; George, S.; Kester, O.; Brodeur, M.; Brunner, T.; Delheij, P.; Dilling, J.; Ettenauer, S.; Lapierre, A.; Bushaw, B.A.; Cano-Ott, D.; Martinez, T.; Cortes, G.; Gomez-Hornillos, M.B.; Dax, A.; Herlert, A.; Yordanov, D.; De, A.; Dickel, T.; Geissel, H.; Jesch, C.; Kuhl, T.; Petrick, M.; PlaB, W.R.; Scheidenberger, C.; Garcia-Ramos, J.E.; Gartzke, E.; Habs, D.; Szerypo, J.; Thirolf, P.G.; Weber, C.; Gusev, Y.; Nesterenko, D.; Novikov, Y.N.; Popov, A.; Seliverstov, M.; Vasiliev, A.; Vorobjev, G.; Heenen, P.H.; Marx, G.; Schweikhard, L.; Ziegler, F.; Hobein, M.; Schuch, R.; Solders, A.; Suhonen, M.; Huber, G.; Wendt, K.; Huyse, M.; Koudriavtsev, I.; Neyens, G.; Van Duppen, P.; Le Blanc, F.; Matos, M.; Reinhard, P.G.; Schneider, D.

    2010-01-01

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. With MATS (Precision Measurements of very short-lived nuclei using an Advanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10 -9 can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. Decay studies in ion traps will become possible with MATS. Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The accuracy of laser-spectroscopic-determined nuclear properties is very high while requirements concerning production rates are moderate. This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy. Since MATS and LaSpec require high-quality low-energy beams

  5. Regional Sm-Nd isotopic study of the central part of the Brasilia belt, Goias: implications of the age and origin of the Anapolis-Itaucu granulitic complex and metasedimentary rocks of the Araxa Group, central region, Brazil

    International Nuclear Information System (INIS)

    Pimentel, Marcio Martins; Fuck, Reinhardt Adolfo; Fischel, Danielle Piuzanna

    1999-01-01

    In the central part of the Brasilia Belt, central Brazil, a high grade terrain, the Anapolis-Itaucu Complex, is exposed within the metasedimentary rocks of the Araxa Group. The Anapolis-Itaucu Complex in Goias represents a complex association of high-grade rocks including mafic-ultramafic bodies, charnockites, enderbites, as well as aluminous granulites of sedimentary origin, associated with marbles and quartzites, Narrow volcano-sedimentary belts formed mainly by amphibolites and micashists are also recognized within the complex. This high-grade terrain has been traditionally interpreted as part of the old (Archaean/Paleoproterozoic) sialic basement to the Neo- or mesoproterozoic sediments of the Araxa Group, Brasilia Belt. The granulites and metasediments of the Araxa Group are intruded by a large number of granite intrusions, many of which slow peraluminous character. Sm-Nd isotopic analyses for the garnet-and sillimanite-bearing aluminous granulites indicate T DM model ages between ca. 1.3 and 1.6 Ga. These values represent the upper limit for the age of the protoliths of the granulites, demonstrating that they are (at least in part) younger than suggested in previous models. The intrusive granites have a Sm-Nd isotopic pattern which is not much different from that observed for the felsic granulites, with T DM model ages ranging in the interval between ca. 1.37 and 1.85 Ga. The isotopic compositions of the granitic and granulitic rocks investigated are also similar to those determined for metasediments of the internal zone of the Brasilia Belt (Araxa Group) in central-southern Goias. These metasediments show Nd model ages between ca. 1.2 and 2.2 Ga. The preliminary isotopic data presented are consistent with a model in which the voluminous granitic magmatism identified in the Anapolis-Itaucu Complex and adjacent areas is Neoproterozoic in age, being the result of re-melting of the older sialic crust. The peraluminous nature of many of these granites

  6. Elemental and Sr-Nd isotopic geochemistry of Cretaceous to Early Paleogene granites and volcanic rocks in the Sikhote-Alin Orogenic Belt (Russian Far East): implications for the regional tectonic evolution

    Science.gov (United States)

    Zhao, Pan; Jahn, Bor-ming; Xu, Bei

    2017-09-01

    The Sikhote-Alin Orogenic Belt in Russian Far East is an important Late Mesozoic to Early Cenozoic accretionary orogen related to the subduction of the Paleo-Pacific Plate. This belt was generated by successive accretion of terranes made of accretionary prisms, turbidite basins and island arcs to the continental margin of northeastern Asia (represented by the Bureya-Jiamusi-Khanka Block) from Jurassic to Late Cretaceous. In order to study the tectonic and crustal evolution of this orogenic belt, we carried out zircon U-Pb dating, and whole-rock elemental and Sr-Nd isotopic analyses on granites and volcanic rocks from the Primorye region of southern Sikhote-Alin. Zircon dating revealed three episodes of granitoid emplacement: Permian, Early Cretaceous and Late Cretaceous to Early Paleogene. Felsic volcanic rocks (mainly rhyolite, dacite and ignimbrite) that overlay all tectonostratigraphic terranes were erupted during 80-57 Ma, postdating the accretionary process in the Sikhote-Alin belt. The Cretaceous-Paleogene magmatism represents the most intense tectonothermal event in the Sikhote-Alin belt. Whole-rock major and trace elemental data show arc-like affinity for granitoids and volcanic rocks, indicating that they were likely generated in a supra-subduction setting. Their initial 87Sr/86Sr ratios range from 0.7048 to 0.7114, and εNd(t) values vary from +1.7 to -3.8 (mostly < 0). Thus, the elemental and Sr-Nd isotopic data suggest that the felsic magmas were generated by partial melting of source rocks comprising mantle-derived juvenile component and recycled crustal component. In addition to the occurrence in the Sikhote-Alin orogenic belt, Cretaceous to Early Paleogene magmatic rocks are also widespread in NE China, southern Korean peninsula, Japanese islands and other areas of Russian Far East, particularly along the coastal regions of the Okhotsk and Bering Seas. These rocks constitute an extended magmatic belt along the continental margin of NE Asia. The

  7. Laser-generated ultrasound for high-precision cutting of tissue-mimicking gels (Conference Presentation)

    Science.gov (United States)

    Lee, Taehwa; Luo, Wei; Li, Qiaochu; Guo, L. Jay

    2017-03-01

    Laser-generated focused ultrasound has shown great promise in precisely treating cells and tissues by producing controlled micro-cavitation within the acoustic focal volume (30 MPa, negative pressure amplitude). By moving cavitation spots along pre-defined paths through a motorized stage, tissue-mimicking gels of different elastic moduli were cut into different shapes (rectangle, triangle, and circle), leaving behind the same shape of holes, whose sizes are less than 1 mm. The cut line width is estimated to be less than 50 um (corresponding to localized cavitation region), allowing for accurate cutting. This novel approach could open new possibility for in-vivo treatment of diseased tissues in a high-precision manner (i.e., high-precision invisible sonic scalpel).

  8. Advances in the Control System for a High Precision Dissolved Organic Carbon Analyzer

    Science.gov (United States)

    Liao, M.; Stubbins, A.; Haidekker, M.

    2017-12-01

    Dissolved organic carbon (DOC) is a master variable in aquatic ecosystems. DOC in the ocean is one of the largest carbon stores on earth. Studies of the dynamics of DOC in the ocean and other low DOC systems (e.g. groundwater) are hindered by the lack of high precision (sub-micromolar) analytical techniques. Results are presented from efforts to construct and optimize a flow-through, wet chemical DOC analyzer. This study focused on the design, integration and optimization of high precision components and control systems required for such a system (mass flow controller, syringe pumps, gas extraction, reactor chamber with controlled UV and temperature). Results of the approaches developed are presented.

  9. A High-precision Motion Compensation Method for SAR Based on Image Intensity Optimization

    Directory of Open Access Journals (Sweden)

    Hu Ke-bin

    2015-02-01

    Full Text Available Owing to the platform instability and precision limitations of motion sensors, motion errors negatively affect the quality of synthetic aperture radar (SAR images. The autofocus Back Projection (BP algorithm based on the optimization of image sharpness compensates for motion errors through phase error estimation. This method can attain relatively good performance, while assuming the same phase error for all pixels, i.e., it ignores the spatial variance of motion errors. To overcome this drawback, a high-precision motion error compensation method is presented in this study. In the proposed method, the Antenna Phase Centers (APC are estimated via optimization using the criterion of maximum image intensity. Then, the estimated APCs are applied for BP imaging. Because the APC estimation equals the range history estimation for each pixel, high-precision phase compensation for every pixel can be achieved. Point-target simulations and processing of experimental data validate the effectiveness of the proposed method.

  10. Laser-Induced Focused Ultrasound for Cavitation Treatment: Toward High-Precision Invisible Sonic Scalpel.

    Science.gov (United States)

    Lee, Taehwa; Luo, Wei; Li, Qiaochu; Demirci, Hakan; Guo, L Jay

    2017-10-01

    Beyond the implementation of the photoacoustic effect to photoacoustic imaging and laser ultrasonics, this study demonstrates a novel application of the photoacoustic effect for high-precision cavitation treatment of tissue using laser-induced focused ultrasound. The focused ultrasound is generated by pulsed optical excitation of an efficient photoacoustic film coated on a concave surface, and its amplitude is high enough to produce controllable microcavitation within the focal region (lateral focus <100 µm). Such microcavitation is used to cut or ablate soft tissue in a highly precise manner. This work demonstrates precise cutting of tissue-mimicking gels as well as accurate ablation of gels and animal eye tissues. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Application of MCU to intelligent interface of high precision magnet power supply

    International Nuclear Information System (INIS)

    Xu Ruinian; Li Deming

    2004-01-01

    Application of the high-capability MCU in the intelligent interface is introduced in this paper. A prototype of intelligent interface for high precision huge magnet power supply was developed successfully. This intelligent interface was composed of two parts: operation panel and main board, both of which adopt a MCU of PIC16F877 respectively. The interface has many advantages, such as small size, low cost and good interference immunity. (authors)

  12. High Precision Fast Projective Synchronization for Chaotic Systems with Unknown Parameters

    Science.gov (United States)

    Nian, Fuzhong; Wang, Xingyuan; Lin, Da; Niu, Yujun

    2013-08-01

    A high precision fast projective synchronization method for chaotic systems with unknown parameters was proposed by introducing optimal matrix. Numerical simulations indicate that the precision be improved about three orders compared with other common methods under the same condition of software and hardware. Moreover, when average error is less than 10-3, the synchronization speed is 6500 times than common methods, the iteration needs only 4 times. The unknown parameters also were identified rapidly. The theoretical analysis and proof also were given.

  13. Physics of Eclipsing Binaries: Modelling in the new era of ultra-high precision photometry

    OpenAIRE

    Pavlovski, K.; Bloemen, S.; Degroote, P.; Conroy, K.; Hambleton, Kelly; Giammarco, J.M.; Pablo, H.; Prša, A.; Tkachenko, A.; Torres, G.

    2013-01-01

    Recent ultra-high precision observations of eclipsing binaries, especially data acquired by the Kepler satellite, have made accurate light curve modelling increasingly challenging but also more rewarding. In this contribution, we discuss low-amplitude signals in light curves that can now be used to derive physical information about eclipsing binaries but that were unaccessible before the Kepler era. A notable example is the detection of Doppler beaming, which leads to an increase in flux when...

  14. The Multi-energy High precision Data Processor Based on AD7606

    Science.gov (United States)

    Zhao, Chen; Zhang, Yanchi; Xie, Da

    2017-11-01

    This paper designs an information collector based on AD7606 to realize the high-precision simultaneous acquisition of multi-source information of multi-energy systems to form the information platform of the energy Internet at Laogang with electricty as its major energy source. Combined with information fusion technologies, this paper analyzes the data to improve the overall energy system scheduling capability and reliability.

  15. Research on Ship Trajectory Tracking with High Precision Based on LOS

    Directory of Open Access Journals (Sweden)

    Hengzhi Liu

    2018-01-01

    Full Text Available Aiming at how precise to track by LOS, a method is proposed. The method combines the advantages of LOS simplicity and intuition, easy parameter setting and good convergence, with the features of GPC softening, multi-step prediction, rolling optimization and excellent controllability and robustness. In order to verify the effectiveness of the method, the method is simulated by Matlab. The simulation’s results show that it makes ship tracking highly precise.

  16. Design and algorithm research of high precision airborne infrared touch screen

    Science.gov (United States)

    Zhang, Xiao-Bing; Wang, Shuang-Jie; Fu, Yan; Chen, Zhao-Quan

    2016-10-01

    There are shortcomings of low precision, touch shaking, and sharp decrease of touch precision when emitting and receiving tubes are failure in the infrared touch screen. A high precision positioning algorithm based on extended axis is proposed to solve these problems. First, the unimpeded state of the beam between emitting and receiving tubes is recorded as 0, while the impeded state is recorded as 1. Then, the method of oblique scan is used, in which the light of one emitting tube is used for five receiving tubes. The impeded information of all emitting and receiving tubes is collected as matrix. Finally, according to the method of arithmetic average, the position of the touch object is calculated. The extended axis positioning algorithm is characteristic of high precision in case of failure of individual infrared tube and affects slightly the precision. The experimental result shows that the 90% display area of the touch error is less than 0.25D, where D is the distance between adjacent emitting tubes. The conclusion is gained that the algorithm based on extended axis has advantages of high precision, little impact when individual infrared tube is failure, and using easily.

  17. Super high precision 200 ppi liquid crystal display series; Chokoseido 200 ppi ekisho display series

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    In mobile equipment, in demand is a high precision liquid crystal display (LCD) having the power of expression equivalent to printed materials like magazines because of the necessity of displaying a large amount of information on a easily potable small screen. In addition, with the spread and high-quality image of digital still cameras, it is strongly desired to display photographed digital image data in high quality. Toshiba Corp., by low temperature polysilicone (p-Si) technology, commercialized the liquid crystal display series of 200 ppi (pixels per inch) precision dealing with the rise of the high-precision high-image quality LCD market. The super high precision of 200 ppi enables the display of smooth beautiful animation comparable to printed sheets of magazines and photographs. The display series are suitable for the display of various information services such as electronic books and electronic photo-viewers including internet. The screen sizes lined up are No. 4 type VGA (640x480 pixels) of a small pocket notebook size and No. 6.3 type XGA (1,024x768 pixels) of a paperback size, with a larger screen to be furthered. (translated by NEDO)

  18. Concept of modular flexure-based mechanisms for ultra-high precision robot design

    Directory of Open Access Journals (Sweden)

    M. Richard

    2011-05-01

    Full Text Available This paper introduces a new concept of modular flexure-based mechanisms to design industrial ultra-high precision robots, which aims at significantly reducing both the complexity of their design and their development time. This modular concept can be considered as a robotic Lego, where a finite number of building bricks is used to quickly build a high-precision robot. The core of the concept is the transformation of a 3-D design problem into several 2-D ones, which are simpler and well-mastered. This paper will first briefly present the theoretical bases of this methodology and the requirements of both types of building bricks: the active and the passive bricks. The section dedicated to the design of the active bricks will detail the current research directions, mainly the maximisation of the strokes and the development of an actuation sub-brick. As for the passive bricks, some examples will be presented, and a discussion regarding the establishment of a mechanical solution catalogue will conclude the section. Last, this modular concept will be illustrated with a practical example, consisting in the design of a 5-degree of freedom ultra-high precision robot.

  19. High-precision measurements of extensive air showers with the SKA

    NARCIS (Netherlands)

    Huege, T.; Bray, J. D.; Buitink, S.; Dallier, R.; Ekers, R. D.; Falcke, H.; Haungs, A.; James, C. W.; Martin, L.; Revenu, B.; Scholten, O.; Schröder, F. G.; Zilles, A.

    2015-01-01

    As of 2023, the Square Kilometre Array will constitute the world's largest radio telescope, offering unprecedented capabilities for a diverse science programme in radio astronomy. At the same time, the SKA will be ideally suited to detect extensive air showers initiated by cosmic rays in the Earth's

  20. High precision measurement of fuel density profiles in nuclear fusion plasmas

    NARCIS (Netherlands)

    Svensson, J.; von Hellermann, M.; Konig, R.

    2002-01-01

    This paper presents a method for deducing fuel density profiles of nuclear fusion plasmas in realtime during an experiment. A Multi Layer Perceptron (MLP) neural network is used to create a mapping between plasma radiation spectra and indirectly deduced hydrogen isotope densities. By combining

  1. Using a Time Projection Chamber to Measure High Precision Neutron-Induced Fission Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Manning, Brett [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-06

    2014 LANSCE run cycle data will provide a preliminary 239Pu(n,f) cross section and will quantify uncertainties: PID and Target/beam non-uniformities. Continued running during the 2015 LANSCE run cycle: Thin targets to see both fission fragments and 239Pu(n,f) cross section and fully quantified uncertainties

  2. Validation of the Cristallini Sampling Method for UF6 by High Precision Double-Spike Measurements

    OpenAIRE

    RICHTER STEPHAN; JAKOBSSON ULF; HIESS JOE; AMARAGGI D.

    2017-01-01

    The so-called "Cristallini Method" for sampling of UF6 by adsorption and hydrolysis in alumina pellets inside a fluorothene P-10 tube was developed by the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) several years ago. This method has several advantages compared to the currently used sampling method, for which UF6 is distilled into a stainless steel tube for transportation, with hydrolysis and isotopic analysis being performed after shipping to the analyt...

  3. High-precision measurements of cementless acetabular components using model-based RSA: an experimental study

    DEFF Research Database (Denmark)

    Baad-Hansen, Thomas; Kold, Søren; Kaptein, Bart L

    2007-01-01

    BACKGROUND: In RSA, tantalum markers attached to metal-backed acetabular cups are often difficult to detect on stereo radiographs due to the high density of the metal shell. This results in occlusion of the prosthesis markers and may lead to inconclusive migration results. Within the last few years...

  4. IAEA/WHO TLD postal dose audit service and high precision measurements for radiotherapy level dosimetry

    International Nuclear Information System (INIS)

    Izewska, J.; Bera, P.; Vatnitsky, S.

    2002-01-01

    Since 1969 the International Atomic Energy Agency, together with the World Health Organization, has performed postal TLD audits to verify calibration of radiotherapy beams in developing countries. The TLD programme also monitors activities of Secondary Standard Dosimetry Laboratories (SSDLs). The programme has checked approximately 4000 clinical beams in over 1100 hospitals, and in many instances significant errors have been detected in the beam calibration. Subsequent follow-up actions help to resolve the discrepancies, thus preventing further mistreatment of patients. The audits for SSDLs check the implementation of the dosimetry protocol in order to assure proper dissemination of dosimetry standards to the end-users. The TLD audit results for SSDLs show good consistency in the basic dosimetry worldwide. New TLD procedures and equipment have recently been introduced by the IAEA that include a modified TLD calibration methodology and computerised tools for automation of dose calculation from TLD readings. (author)

  5. A NEW GAS CELL FOR HIGH-PRECISION DOPPLER MEASUREMENTS IN THE NEAR-INFRARED

    International Nuclear Information System (INIS)

    Valdivielso, L.; Esparza, P.; MartIn, E. L.; Maukonen, D.; Peale, R. E.

    2010-01-01

    High-resolution spectroscopy in the near-infrared could become the leading method for discovering extra-solar planets around very low mass stars and brown dwarfs. In order to help to achieve an accuracy of ∼m s -1 , we are developing a gas cell which consists of a mixture of gases whose absorption spectral lines span all over the near-infrared region. We present the most promising mixture, made of acetylene, nitrous oxide, ammonia, chloromethanes, and hydrocarbons. The mixture is contained in a small size 13 cm long gas cell and covers most of the H and K bands. It also shows small absorptions in the J band, but they are few and not sharp enough for near-infrared wavelength calibration. We describe the working method and experiments, and compare our results with the state of the art for near-infrared gas cells.

  6. CHEOPS: a space telescope for ultra-high precision photometry of exoplanet transits

    Science.gov (United States)

    Cessa, V.; Beck, T.; Benz, W.; Broeg, C.; Ehrenreich, D.; Fortier, A.; Peter, G.; Magrin, D.; Pagano, I.; Plesseria, J.-Y.; Steller, M.; Szoke, J.; Thomas, N.; Ragazzoni, R.; Wildi, F.

    2017-11-01

    The CHaracterising ExOPlanet Satellite (CHEOPS) is a joint ESA-Switzerland space mission dedicated to search for exoplanet transits by means of ultra-high precision photometry whose launch readiness is expected end 2017. The CHEOPS instrument will be the first space telescope dedicated to search for transits on bright stars already known to host planets. By being able to point at nearly any location on the sky, it will provide the unique capability of determining accurate radii for a subset of those planets for which the mass has already been estimated from ground-based spectroscopic surveys. CHEOPS will also provide precision radii for new planets discovered by the next generation ground-based transits surveys (Neptune-size and smaller). The main science goals of the CHEOPS mission will be to study the structure of exoplanets with radii typically ranging from 1 to 6 Earth radii orbiting bright stars. With an accurate knowledge of masses and radii for an unprecedented sample of planets, CHEOPS will set new constraints on the structure and hence on the formation and evolution of planets in this mass range. To reach its goals CHEOPS will measure photometric signals with a precision of 20 ppm in 6 hours of integration time for a 9th magnitude star. This corresponds to a signal to noise of 5 for a transit of an Earth-sized planet orbiting a solar-sized star (0.9 solar radii). This precision will be achieved by using a single frame-transfer backside illuminated CCD detector cool down at 233K and stabilized within {10 mK . The CHEOPS optical design is based on a Ritchey-Chretien style telescope with 300 mm effective aperture diameter, which provides a defocussed image of the target star while minimizing straylight using a dedicated field stop and baffle system. As CHEOPS will be in a LEO orbit, straylight suppression is a key point to allow the observation of faint stars. The telescope will be the only payload on a spacecraft platform providing pointing stability of

  7. U-Pb, Nd isotope and REE geochemistry in eclogites from the Cabo Ortegal Complex, Galicia, Spain: an example of REE immobility conserving MORB-like patterns during high-grade metamorphism

    International Nuclear Information System (INIS)

    Bernard-Griffiths, J.; Peucat, J.-J.; Cornichet, J.; Iglesias Ponce de Leon, M.; Gil Ibarguchi, J.I.

    1985-01-01

    REE abundances and Nd isotopic compositions were determined on representative samples of eclogite from the Cabo Ortegal Complex of northern Spain. Zircons were also separated from a whole-rock eclogite and analysed by the U-Pb radiometric method. Results indicate that eclogite facies metamorphism occurred between 480 and 420 Ma ago, but no precise constraint can be placed on the protolith age. The REE patterns observed suggest that there has been no significant alteration of the protolith whole-rock systems and that high-grade metamorphism has had little effect on the more mobile LREE. The eclogite protoliths were probably derived from ancient mantle sources with geochemical characteristics very similar to present-day MORB sources. This implies that LREE-depleted (N-type) tholeiites have been erupted at constructive plate margins since at least the early Palaeozoic and possibly long before. The Cabo Ortegal eclogites are allochthonous. They have been thrust up on to the continent and thus they can be compared to other eclogites which also show MORB-like characteristics (e.g., 90% of the eclogites of Vendee area of western France). (orig.)

  8. U-Pb (LA-ICPMS) zircon ages and Nd isotopes for granitoids of the Tamboril-Santa Quiteria Complex, Ceara Central Domain: implication for neoproterozoic syncollisional magmatism in north Borborema Province, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Felipe Grandjean da; Araujo, Carlos Eduardo Ganade de; Vasconcelos, Antonio Maurilio, E-mail: felipe.costa@cprm.gov.br, E-mail: caegeo@gmail.com, E-mail: maurilio.vasconcelos@cprm.gov.br [Servico Geologico do Brasil (CPRM), Fortaleza, CE (Brazil); Amaral, Wagner da Silva, E-mail: wamaral@ufc.br [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Departamento de Geologia; Rodrigues, Joseneusa Brilhante, E-mail: joseneusa.rodrigues@cprm.gov.br [Servico Geologico do Brasil (CPRM), Brasilia, DF (Brazil)

    2013-06-15

    The Tamboril-Santa Quiteria Complex (TSQC) is one of the largest Neoproterozoic plutonic manifestations in the north Borborema Province (NE Brazil). It represents an anatectic/igneous association characterized by a number of magmatic pulses that occurred in the 650-610 Ma interval. In this paper, we present U-Pb (LA-MC-ICP-MS) zircon ages and Nd isotopes for quartz monzonite and quartz diorites of the southern part of TSQC. The quartz monzonite belong to a hybrid granitoid association, including monzonite, syenites and quartz syenites, all with abundant mafic magmatic enclaves. A quartz monzonite sample yielded a U-Pb zircon age of 634 {+-} 10 Ma and a TDM age of 2.69 Ga. The quartz diorites are much more homogeneous in composition and yielded a U-Pb zircon age of 618 {+-} 23 Ma and a TDM age of 2.19 Ga. The presence of coeval mantle-derived magmatism and diatexites (crustal anatexis) post-dating high-pressure metamorphism (ca. 650 Ma), and together with high-temperature metamorphism (ca. 630-610 Ma), suggests that this large magmatic manifestation evolved in a collisional setting, probably related to slab break off during the Western Gondwana amalgamation. (author)

  9. A Police and Insurance Joint Management System Based on High Precision BDS/GPS Positioning

    Science.gov (United States)

    Zuo, Wenwei; Guo, Chi; Liu, Jingnan; Peng, Xuan; Yang, Min

    2018-01-01

    Car ownership in China reached 194 million vehicles at the end of 2016. The traffic congestion index (TCI) exceeds 2.0 during rush hour in some cities. Inefficient processing for minor traffic accidents is considered to be one of the leading causes for road traffic jams. Meanwhile, the process after an accident is quite troublesome. The main reason is that it is almost always impossible to get the complete chain of evidence when the accident happens. Accordingly, a police and insurance joint management system is developed which is based on high precision BeiDou Navigation Satellite System (BDS)/Global Positioning System (GPS) positioning to process traffic accidents. First of all, an intelligent vehicle rearview mirror terminal is developed. The terminal applies a commonly used consumer electronic device with single frequency navigation. Based on the high precision BDS/GPS positioning algorithm, its accuracy can reach sub-meter level in the urban areas. More specifically, a kernel driver is built to realize the high precision positioning algorithm in an Android HAL layer. Thus the third-party application developers can call the general location Application Programming Interface (API) of the original standard Global Navigation Satellite System (GNSS) to get high precision positioning results. Therefore, the terminal can provide lane level positioning service for car users. Next, a remote traffic accident processing platform is built to provide big data analysis and management. According to the big data analysis of information collected by BDS high precision intelligent sense service, vehicle behaviors can be obtained. The platform can also automatically match and screen the data that uploads after an accident to achieve accurate reproduction of the scene. Thus, it helps traffic police and insurance personnel to complete remote responsibility identification and survey for the accident. Thirdly, a rapid processing flow is established in this article to meet the

  10. A Police and Insurance Joint Management System Based on High Precision BDS/GPS Positioning

    Directory of Open Access Journals (Sweden)

    Wenwei Zuo

    2018-01-01

    Full Text Available Car ownership in China reached 194 million vehicles at the end of 2016. The traffic congestion index (TCI exceeds 2.0 during rush hour in some cities. Inefficient processing for minor traffic accidents is considered to be one of the leading causes for road traffic jams. Meanwhile, the process after an accident is quite troublesome. The main reason is that it is almost always impossible to get the complete chain of evidence when the accident happens. Accordingly, a police and insurance joint management system is developed which is based on high precision BeiDou Navigation Satellite System (BDS/Global Positioning System (GPS positioning to process traffic accidents. First of all, an intelligent vehicle rearview mirror terminal is developed. The terminal applies a commonly used consumer electronic device with single frequency navigation. Based on the high precision BDS/GPS positioning algorithm, its accuracy can reach sub-meter level in the urban areas. More specifically, a kernel driver is built to realize the high precision positioning algorithm in an Android HAL layer. Thus the third-party application developers can call the general location Application Programming Interface (API of the original standard Global Navigation Satellite System (GNSS to get high precision positioning results. Therefore, the terminal can provide lane level positioning service for car users. Next, a remote traffic accident processing platform is built to provide big data analysis and management. According to the big data analysis of information collected by BDS high precision intelligent sense service, vehicle behaviors can be obtained. The platform can also automatically match and screen the data that uploads after an accident to achieve accurate reproduction of the scene. Thus, it helps traffic police and insurance personnel to complete remote responsibility identification and survey for the accident. Thirdly, a rapid processing flow is established in this article to

  11. A Police and Insurance Joint Management System Based on High Precision BDS/GPS Positioning.

    Science.gov (United States)

    Zuo, Wenwei; Guo, Chi; Liu, Jingnan; Peng, Xuan; Yang, Min

    2018-01-10

    Car ownership in China reached 194 million vehicles at the end of 2016. The traffic congestion index (TCI) exceeds 2.0 during rush hour in some cities. Inefficient processing for minor traffic accidents is considered to be one of the leading causes for road traffic jams. Meanwhile, the process after an accident is quite troublesome. The main reason is that it is almost always impossible to get the complete chain of evidence when the accident happens. Accordingly, a police and insurance joint management system is developed which is based on high precision BeiDou Navigation Satellite System (BDS)/Global Positioning System (GPS) positioning to process traffic accidents. First of all, an intelligent vehicle rearview mirror terminal is developed. The terminal applies a commonly used consumer electronic device with single frequency navigation. Based on the high precision BDS/GPS positioning algorithm, its accuracy can reach sub-meter level in the urban areas. More specifically, a kernel driver is built to realize the high precision positioning algorithm in an Android HAL layer. Thus the third-party application developers can call the general location Application Programming Interface (API) of the original standard Global Navigation Satellite System (GNSS) to get high precision positioning results. Therefore, the terminal can provide lane level positioning service for car users. Next, a remote traffic accident processing platform is built to provide big data analysis and management. According to the big data analysis of information collected by BDS high precision intelligent sense service, vehicle behaviors can be obtained. The platform can also automatically match and screen the data that uploads after an accident to achieve accurate reproduction of the scene. Thus, it helps traffic police and insurance personnel to complete remote responsibility identification and survey for the accident. Thirdly, a rapid processing flow is established in this article to meet the

  12. High-precision half-life determination for 21Na using a 4 π gas-proportional counter

    Science.gov (United States)

    Finlay, P.; Laffoley, A. T.; Ball, G. C.; Bender, P. C.; Dunlop, M. R.; Dunlop, R.; Hackman, G.; Leslie, J. R.; MacLean, A. D.; Miller, D.; Moukaddam, M.; Olaizola, B.; Severijns, N.; Smith, J. K.; Southall, D.; Svensson, C. E.

    2017-08-01

    A high-precision half-life measurement for the superallowed β+ transition between the isospin T =1 /2 mirror nuclei 21Na and 21Ne has been performed at the TRIUMF-ISAC radioactive ion beam facility yielding T1 /2=22.4506 (33 ) s, a result that is a factor of 4 more precise than the previous world-average half-life for 21Na and represents the single most precisely determined half-life for a transition between mirror nuclei to date. The contribution to the uncertainty in the 21Na F tmirror value due to the half-life is now reduced to the level of the nuclear-structure-dependent theoretical corrections, leaving the branching ratio as the dominant experimental uncertainty.

  13. Detector studies for a high precision determination of the weak mixing angle at the future P2-experiment in Mainz

    Energy Technology Data Exchange (ETDEWEB)

    Gerz, Kathrin; Baunack, Sebastian; Becker, Dominik; Diefenbach, Juergen; Glaeser, Boris; Imai, Yoshio; Jennewein, Thomas [Institut fuer Kernphysik, Johannes-Gutenberg-Universitaet Mainz (Germany); Maas, Frank [Institut fuer Kernphysik, Johannes-Gutenberg-Universitaet Mainz (Germany); Helmholz-Institut Mainz (Germany); PRISMA Cluster of Excellence, Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Rodriguez, David [Helmholz-Institut Mainz (Germany); Collaboration: A4-Collaboration

    2015-07-01

    The P2 experiment at the upcoming MESA accelerator in Mainz aims for a high precision determination of the electroweak mixing angle: The 2% measurement of the parity violating asymmetry in elastic electron-proton scattering will allow for a determination of sin{sup 2}(θ{sub W}) of 0.15%. The experimental setup is currently being designed and will employ the use of an integrating, large solid angle magnetic solenoid spectrometer with quartz bars for the detection of elastically scattered electrons. The low-energy and high-statistics experiment places high demands on detector performance and radiation hardness of all materials used in the setup. We are going to present the current status of the development of the experiment, feasibility calculations and simulations. We put an emphasis on technology and design of a Cherenkov detector.

  14. Extending and refining the mass surface around $^{208}$Pb by high-precision Penning-trap mass spectrometry with ISOLTRAP

    CERN Multimedia

    Herfurth, F; Stora, T; Blaum, K; Beck, D; Kowalska, M; Schwarz, S; Stanja, J; Herlert, A J; Yamaguchi, T

    We propose high-precision mass spectrometry of nuclides around the doubly magic $^{208}$Pb. On the neutron-rich side, we aim to extend the knowledge of Fr, At, Hg, and Au masses to study the robustness of the N = 126 shell closure and to provide mass data necessary for modeling the rapid-neutron-capture process. On the proton-rich side, we aim at high-resolution mass spectrometry of selected Au, At, and Fr isotopes to verify the predicted existence of very low-lying isomeric states. The proposal will make use of newly-available laser-ionization schemes for Au and At. Finally, the recently implemented multi-reflection time-of-flight mass separator for auxiliary isobaric purification now allows measurements which were not feasible before.

  15. WE-AB-202-09: Feasibility and Quantitative Analysis of 4DCT-Based High Precision Lung Elastography

    International Nuclear Information System (INIS)

    Hasse, K; Neylon, J; Low, D; Santhanam, A

    2016-01-01

    Purpose: The purpose of this project is to derive high precision elastography measurements from 4DCT lung scans to facilitate the implementation of elastography in a radiotherapy context. Methods: 4DCT scans of the lungs were acquired, and breathing stages were subsequently registered to each other using an optical flow DIR algorithm. The displacement of each voxel gleaned from the registration was taken to be the ground-truth deformation. These vectors, along with the 4DCT source datasets, were used to generate a GPU-based biomechanical simulation that acted as a forward model to solve the inverse elasticity problem. The lung surface displacements were applied as boundary constraints for the model-guided lung tissue elastography, while the inner voxels were allowed to deform according to the linear elastic forces within the model. A biomechanically-based anisotropic convergence magnification technique was applied to the inner voxels in order to amplify the subtleties of the interior deformation. Solving the inverse elasticity problem was accomplished by modifying the tissue elasticity and iteratively deforming the biomechanical model. Convergence occurred when each voxel was within 0.5 mm of the ground-truth deformation and 1 kPa of the ground-truth elasticity distribution. To analyze the feasibility of the model-guided approach, we present the results for regions of low ventilation, specifically, the apex. Results: The maximum apical boundary expansion was observed to be between 2 and 6 mm. Simulating this expansion within an apical lung model, it was observed that 100% of voxels converged within 0.5 mm of ground-truth deformation, while 91.8% converged within 1 kPa of the ground-truth elasticity distribution. A mean elasticity error of 0.6 kPa illustrates the high precision of our technique. Conclusion: By utilizing 4DCT lung data coupled with a biomechanical model, high precision lung elastography can be accurately performed, even in low ventilation regions of

  16. WE-AB-202-09: Feasibility and Quantitative Analysis of 4DCT-Based High Precision Lung Elastography

    Energy Technology Data Exchange (ETDEWEB)

    Hasse, K; Neylon, J; Low, D; Santhanam, A [UCLA, Los Angeles, CA (United States)

    2016-06-15

    Purpose: The purpose of this project is to derive high precision elastography measurements from 4DCT lung scans to facilitate the implementation of elastography in a radiotherapy context. Methods: 4DCT scans of the lungs were acquired, and breathing stages were subsequently registered to each other using an optical flow DIR algorithm. The displacement of each voxel gleaned from the registration was taken to be the ground-truth deformation. These vectors, along with the 4DCT source datasets, were used to generate a GPU-based biomechanical simulation that acted as a forward model to solve the inverse elasticity problem. The lung surface displacements were applied as boundary constraints for the model-guided lung tissue elastography, while the inner voxels were allowed to deform according to the linear elastic forces within the model. A biomechanically-based anisotropic convergence magnification technique was applied to the inner voxels in order to amplify the subtleties of the interior deformation. Solving the inverse elasticity problem was accomplished by modifying the tissue elasticity and iteratively deforming the biomechanical model. Convergence occurred when each voxel was within 0.5 mm of the ground-truth deformation and 1 kPa of the ground-truth elasticity distribution. To analyze the feasibility of the model-guided approach, we present the results for regions of low ventilation, specifically, the apex. Results: The maximum apical boundary expansion was observed to be between 2 and 6 mm. Simulating this expansion within an apical lung model, it was observed that 100% of voxels converged within 0.5 mm of ground-truth deformation, while 91.8% converged within 1 kPa of the ground-truth elasticity distribution. A mean elasticity error of 0.6 kPa illustrates the high precision of our technique. Conclusion: By utilizing 4DCT lung data coupled with a biomechanical model, high precision lung elastography can be accurately performed, even in low ventilation regions of

  17. Rigorous high-precision enclosures of fixed points and their invariant manifolds

    Science.gov (United States)

    Wittig, Alexander N.

    The well established concept of Taylor Models is introduced, which offer highly accurate C0 enclosures of functional dependencies, combining high-order polynomial approximation of functions and rigorous estimates of the truncation error, performed using verified arithmetic. The focus of this work is on the application of Taylor Models in algorithms for strongly non-linear dynamical systems. A method is proposed to extend the existing implementation of Taylor Models in COSY INFINITY from double precision coefficients to arbitrary precision coefficients. Great care is taken to maintain the highest efficiency possible by adaptively adjusting the precision of higher order coefficients in the polynomial expansion. High precision operations are based on clever combinations of elementary floating point operations yielding exact values for round-off errors. An experimental high precision interval data type is developed and implemented. Algorithms for the verified computation of intrinsic functions based on the High Precision Interval datatype are developed and described in detail. The application of these operations in the implementation of High Precision Taylor Models is discussed. An application of Taylor Model methods to the verification of fixed points is presented by verifying the existence of a period 15 fixed point in a near standard Henon map. Verification is performed using different verified methods such as double precision Taylor Models, High Precision intervals and High Precision Taylor Models. Results and performance of each method are compared. An automated rigorous fixed point finder is implemented, allowing the fully automated search for all fixed points of a function within a given domain. It returns a list of verified enclosures of each fixed point, optionally verifying uniqueness within these enclosures. An application of the fixed point finder to the rigorous analysis of beam transfer maps in accelerator physics is presented. Previous work done by

  18. The Effects of L2C Signal Tracking on High-Precision Carrier Phase GPS Positioning

    Science.gov (United States)

    Berglund, H.; Blume, F.; Estey, L. H.; Borsa, A. A.

    2010-12-01

    In 2005, the L2C signal was introduced to improve the accuracy, tracking and redundancy of the GPS system for civilian users. The L2C signal also provides improved SNR data when compared with the L2P(Y) legacy signal, comparable to that of the L1 C/A-code, which allows for better tracking at lower elevations. With the recent launch of the first block II-F satellite (SVN62/PRN25), there are 8 healthy satellites broadcasting L2C signals, or 25% of the constellation. However, GNSS network operators such as the UNAVCO Plate Boundary Observatory (PBO) have been hesitant to use the new signal as it is not well determined how tracking and logging L2C could affect the positions derived from L2 carrier phase measurements for a given receiver. The L2C carrier phase is in quadrature (90° out of phase) with the L2P(Y) phase that has been used by high-precision positioning software since the beginning of GPS. To complicate matters further, some receiver manufacturers (e.g. Trimble) correct for this when logging L2C phase while others (e.g. Topcon) do not. The L2C capability of receivers currently in widespread use in permanent networks can depend on firmware as well as hardware; in some cases receivers can simultaneously track L2C and L2P(Y) phases and some can track only one or the other, and the resulting observation files can depend on how individual operators configure the devices. In cases where both L2C and L2P(Y) are logged simultaneously, translation software (such as UNAVCO’s teqc) must be used carefully in order to select which L2 observation is written to RINEX (2.11) and used in positioning. Modifications were recently made to teqc to eliminate potential confusion in that part of the process; if L2C code observations appear in a RINEX (2.11) file produced by teqc, the L2 phase and S2 SNR observations were from the L2C carrier for those satellites. To date L2C analyses have been restricted to special applications such as snow depth and soil moisture using SNR data

  19. Reference satellite selection method for GNSS high-precision relative positioning

    Directory of Open Access Journals (Sweden)

    Xiao Gao

    2017-03-01

    Full Text Available Selecting the optimal reference satellite is an important component of high-precision relative positioning because the reference satellite directly influences the strength of the normal equation. The reference satellite selection methods based on elevation and positional dilution of precision (PDOP value were compared. Results show that all the above methods cannot select the optimal reference satellite. We introduce condition number of the design matrix in the reference satellite selection method to improve structure of the normal equation, because condition number can indicate the ill condition of the normal equation. The experimental results show that the new method can improve positioning accuracy and reliability in precise relative positioning.

  20. Design and implementation of high-precision and low-jitter programmable delay circuitry

    International Nuclear Information System (INIS)

    Gao Yuan; Cui Ke; Zhang Hongfei; Luo Chunli; Yang Dongxu; Liang Hao; Wang Jian

    2011-01-01

    A programmable delay circuit design which has characteristics of high-precision, low-jitter, wide-programmable-range and low power is introduced. The delay circuitry uses the scheme which has two parts: the coarse delay and the fine delay that could be controlled separately. Using different coarse delay chip can reach different maximum programmable range. And the fine delay programmable chip has the minimum step which is down to 10 ps. The whole circuitry jitter will be less than 100 ps. The design has been successfully applied in Quantum Key Distribution experiment. (authors)

  1. Design of high precision temperature control system for TO packaged LD

    Science.gov (United States)

    Liang, Enji; Luo, Baoke; Zhuang, Bin; He, Zhengquan

    2017-10-01

    Temperature is an important factor affecting the performance of TO package LD. In order to ensure the safe and stable operation of LD, a temperature control circuit for LD based on PID technology is designed. The MAX1978 and an external PID circuit are used to form a control circuit that drives the thermoelectric cooler (TEC) to achieve control of temperature and the external load can be changed. The system circuit has low power consumption, high integration and high precision,and the circuit can achieve precise control of the LD temperature. Experiment results show that the circuit can achieve effective and stable control of the laser temperature.

  2. A new approach to the BFKL mechanism. Application to high-precision HERA data

    International Nuclear Information System (INIS)

    Kowalski, H.; Lipatov, L.N.; Ross, D.A.

    2017-07-01

    We analyse here in NLO the physical properties of the discrete eigenvalue solution for the BFKL equation. We show that a set of positive ω eigenfunctions together with a small contribution from a continuum of negative ω's provide an excellent description of high-precision HERA F_2 data in the region, x 6 GeV"2. The phases of the eigenfunctions can be obtained from a simple parametrisation of the pomeron spectrum, which has a natural motivation within BFKL. The data analysis shows that the first eigenfunction decouples or nearly decouples from the proton. This suggests that there exist an additional ground state, which has no nodes.

  3. Dimethyl ether reviewed: New results on using this gas in a high-precision drift chamber

    International Nuclear Information System (INIS)

    Basile, M.; Bonvicini, G.; Cara Romeo, G.; Cifarelli, L.; Contin, A.; D'Ali, G.; Del Papa, C.; Maccarrone, G.; Massam, T.; Motta, F.; Nania, R.; Palmonari, F.; Rinaldi, G.; Sartorelli, G.; Spinetti, M.; Susinno, G.; Villa, F.; Voltano, L.; Zichichi, A.

    1985-01-01

    Two years ago, dimethyl ether (DME) was presented, for the first time, as a suitable gas for high-precision drift chambers. In fact our tests show that resolutions can be obtained which are better by at least a factor of 2 compared to what one can get with conventional gases. Moreover, DME is very well quenched. The feared formation of whiskers on the wires has not occurred, at least after months of use with a 10 μCi 106 Ru source. (orig.)

  4. MiniDSS: a low-power and high-precision miniaturized digital sun sensor

    Science.gov (United States)

    de Boer, B. M.; Durkut, M.; Laan, E.; Hakkesteegt, H.; Theuwissen, A.; Xie, N.; Leijtens, J. L.; Urquijo, E.; Bruins, P.

    2017-11-01

    A high-precision and low-power miniaturized digital sun sensor has been developed at TNO. The single-chip sun sensor comprises an application specific integrated circuit (ASIC) on which an active pixel sensor (APS), read-out and processing circuitry as well as communication circuitry are combined. The design was optimized for low recurrent cost. The sensor is albedo insensitive and the prototype combines an accuracy in the order of 0.03° with a mass of just 72 g and a power consumption of only 65 mW.

  5. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Fasanella, Giuseppe

    2017-01-01

    The CMS Electromagnetic Calorimeter utilizes scintillating lead tungstate crystals, with avalanche photodiodes (APD) as photo-detectors in the barrel part. 1224 HV channels bias groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  6. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Marzocchi, Badder

    2017-01-01

    The CMS Electromagnetic Calorimeter is made of scintillating lead tungstate crystals, using avalanche photodiodes (APD) as photo-detectors in the barrel part. The high voltage system, consisting of 1224 channels, biases groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  7. High precision simple interpolation asynchronous FIFO based on ACEX1K30 for HIRFL-CSRe

    International Nuclear Information System (INIS)

    Li Guihua; Qiao Weimin; Jing Lan

    2008-01-01

    High precision simple interpolation asynchronous FIFO of HIRFL-CSRe was developed based on the ACEX1K30 FPGA in VHDL Hardware Description language. The FIFO runs in FPGA of DSP module of HIRFL-CSRe. The input data of FIFO is from DSP data bus and the output data is to DAC data bus. It's kernel adopts double buffer ping-pong mode and it can implement simple interpolation inside FPGA. The module can control out- put data time delay in 40 ns. The experimental results indicate that this module is practical and accurate to HIRFL-CSRe. (authors)

  8. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Fasanella, Giuseppe

    2016-01-01

    The CMS Electromagnetic Calorimeter utilizes scintillating lead tungstate crystals, with avalanche photodiodes (APD) as photo-detectors in the barrel part. 1224 HV channels bias groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  9. Method of semi-automatic high precision potentiometric titration for characterization of uranium compounds

    International Nuclear Information System (INIS)

    Cristiano, Barbara Fernandes G.; Dias, Fabio C.; Barros, Pedro D. de; Araujo, Radier Mario S. de; Delgado, Jose Ubiratan; Silva, Jose Wanderley S. da; Lopes, Ricardo T.

    2011-01-01

    The method of high precision potentiometric titration is widely used in the certification and characterization of uranium compounds. In order to reduce the analysis and diminish the influence if the annalist, a semi-automatic version of the method was developed at the safeguards laboratory of the CNEN-RJ, Brazil. The method was applied with traceability guaranteed by use of primary standard of potassium dichromate. The standard uncertainty combined in the determination of concentration of total uranium was of the order of 0.01%, which is better related to traditionally methods used by the nuclear installations which is of the order of 0.1%

  10. The application of integrated geophysical methods composed of AMT and high-precision ground magnetic survey to the exploration of granite uranium deposits

    International Nuclear Information System (INIS)

    Qiao Yong; Shen Jingbang; Wu Yong; Wang Zexia

    2014-01-01

    Introduced two methods composed of AMT and high-precision ground magnetic survey were used to the exploration of granite uranium deposits in the Yin gongshan areas middle part of the Nei Monggol. Through experiment of methods and analysis of applicated results, think that AMT have good vertical resolution and could preferably survey thickness of rockmass, position of fracture and deep conditions, space distribution features of fracture zone ect, but it is not clear for rockmass, xenolith of reflection. And high-precision ground magnetic survey could delineate rockmass, xenolith of distribution range and identify the rock contact zone, fracture ect, but it generally measure position and it is not clear for occurrence, extension. That can resolve some geological structures by using the integrated methods and on the basis of sharing their complementary advantages. Effective technological measures are provided to the exploration of deep buried uranium bodies in the granite uranium deposits and outskirt extension of the deposit. (authors)

  11. The honeycomb strip chamber: A two coordinate and high precision muon detector

    International Nuclear Information System (INIS)

    Tolsma, H.P.T.

    1996-01-01

    This thesis describes the construction and performance of the Honeycomb Strip Chamber (HSC). The HSC offers several advantages with respect to classical drift chambers and drift tubes. The main features of the HSC are: -The detector offers the possibility of simultaneous readout of two orthogonal coordinates with approximately the same precision. - The HSC technology is optimised for mass production. This means that the design is modular (monolayers) and automisation of most of the production steps is possible (folding and welding machines). - The technology is flexible. The cell diameter can easily be changed from a few millimetres to at least 20 mm by changing the parameters in the computer programme of the folding machine. The number of monolayers per station can be chosen freely to the demands of the experiment. -The honeycomb structure gives the detector stiffness and makes it self supporting. This makes the technology a very transparent one in terms of radiation length which is important to prevent multiple scattering of high energetic muons. - The dimensions of the detector are defined by high precision templates. Those templates constrain for example the overall tolerance on the wire positions to 20 μm rms. Reproduction of the high precision assembly of the detector is thus guaranteed. (orig.)

  12. Using cold deformation methods in flow-production of steel high precision shaped sections

    International Nuclear Information System (INIS)

    Zajtsev, M.L.; Makhnev, I.F.; Shkurko, I.I.

    1975-01-01

    A final size with a preset tolerance and a required surface finish of steel high-precision sections could be achieved by a cold deformation of hot-rolled ingots-by drawing through dismountable, monolith or roller-type drawing tools or by cold rolling in roller dies. The particularities of the both techniques are compared as regards a number of complicated shaped sections and the advantages of cold rolling are showna more uniform distribution of deformations (strain hardening) across the section, that is a greater margin of plasticity with the same reductions, the less number of the operations required. Rolling is recommended in all the cases when possible as regards the section shape and the bulk volume. The rolling-mill for the calibration of high-precision sections should have no less than two shafts (so that the size could be controlled in both directions) and arrangements to withstand high axial stresses on the rollers (the stresses appearing during rolling in skew dies). When manufacturing precise shaped sections by the cold rolling method the operations are less plentiful than in the cold drawing manufacturing

  13. A Fast and High-precision Orientation Algorithm for BeiDou Based on Dimensionality Reduction

    Directory of Open Access Journals (Sweden)

    ZHAO Jiaojiao

    2015-05-01

    Full Text Available A fast and high-precision orientation algorithm for BeiDou is proposed by deeply analyzing the constellation characteristics of BeiDou and GEO satellites features.With the advantage of good east-west geometry, the baseline vector candidate values were solved by the GEO satellites observations combined with the dimensionality reduction theory at first.Then, we use the ambiguity function to judge the values in order to obtain the optical baseline vector and get the wide lane integer ambiguities. On this basis, the B1 ambiguities were solved. Finally, the high-precision orientation was estimated by the determinating B1 ambiguities. This new algorithm not only can improve the ill-condition of traditional algorithm, but also can reduce the ambiguity search region to a great extent, thus calculating the integer ambiguities in a single-epoch.The algorithm is simulated by the actual BeiDou ephemeris and the result shows that the method is efficient and fast for orientation. It is capable of very high single-epoch success rate(99.31% and accurate attitude angle (the standard deviation of pitch and heading is respectively 0.07°and 0.13°in a real time and dynamic environment.

  14. A high precision extrapolation method in multiphase-field model for simulating dendrite growth

    Science.gov (United States)

    Yang, Cong; Xu, Qingyan; Liu, Baicheng

    2018-05-01

    The phase-field method coupling with thermodynamic data has become a trend for predicting the microstructure formation in technical alloys. Nevertheless, the frequent access to thermodynamic database and calculation of local equilibrium conditions can be time intensive. The extrapolation methods, which are derived based on Taylor expansion, can provide approximation results with a high computational efficiency, and have been proven successful in applications. This paper presents a high precision second order extrapolation method for calculating the driving force in phase transformation. To obtain the phase compositions, different methods in solving the quasi-equilibrium condition are tested, and the M-slope approach is chosen for its best accuracy. The developed second order extrapolation method along with the M-slope approach and the first order extrapolation method are applied to simulate dendrite growth in a Ni-Al-Cr ternary alloy. The results of the extrapolation methods are compared with the exact solution with respect to the composition profile and dendrite tip position, which demonstrate the high precision and efficiency of the newly developed algorithm. To accelerate the phase-field and extrapolation computation, the graphic processing unit (GPU) based parallel computing scheme is developed. The application to large-scale simulation of multi-dendrite growth in an isothermal cross-section has demonstrated the ability of the developed GPU-accelerated second order extrapolation approach for multiphase-field model.

  15. High-Precision Phenotyping of Grape Bunch Architecture Using Fast 3D Sensor and Automation

    Directory of Open Access Journals (Sweden)

    Florian Rist

    2018-03-01

    Full Text Available Wine growers prefer cultivars with looser bunch architecture because of the decreased risk for bunch rot. As a consequence, grapevine breeders have to select seedlings and new cultivars with regard to appropriate bunch traits. Bunch architecture is a mosaic of different single traits which makes phenotyping labor-intensive and time-consuming. In the present study, a fast and high-precision phenotyping pipeline was developed. The optical sensor Artec Spider 3D scanner (Artec 3D, L-1466, Luxembourg was used to generate dense 3D point clouds of grapevine bunches under lab conditions and an automated analysis software called 3D-Bunch-Tool was developed to extract different single 3D bunch traits, i.e., the number of berries, berry diameter, single berry volume, total volume of berries, convex hull volume of grapes, bunch width and bunch length. The method was validated on whole bunches of different grapevine cultivars and phenotypic variable breeding material. Reliable phenotypic data were obtained which show high significant correlations (up to r2 = 0.95 for berry number compared to ground truth data. Moreover, it was shown that the Artec Spider can be used directly in the field where achieved data show comparable precision with regard to the lab application. This non-invasive and non-contact field application facilitates the first high-precision phenotyping pipeline based on 3D bunch traits in large plant sets.

  16. The honeycomb strip chamber: A two coordinate and high precision muon detector

    Energy Technology Data Exchange (ETDEWEB)

    Tolsma, H P.T.

    1996-04-19

    This thesis describes the construction and performance of the Honeycomb Strip Chamber (HSC). The HSC offers several advantages with respect to classical drift chambers and drift tubes. The main features of the HSC are: -The detector offers the possibility of simultaneous readout of two orthogonal coordinates with approximately the same precision. - The HSC technology is optimised for mass production. This means that the design is modular (monolayers) and automisation of most of the production steps is possible (folding and welding machines). - The technology is flexible. The cell diameter can easily be changed from a few millimetres to at least 20 mm by changing the parameters in the computer programme of the folding machine. The number of monolayers per station can be chosen freely to the demands of the experiment. -The honeycomb structure gives the detector stiffness and makes it self supporting. This makes the technology a very transparent one in terms of radiation length which is important to prevent multiple scattering of high energetic muons. - The dimensions of the detector are defined by high precision templates. Those templates constrain for example the overall tolerance on the wire positions to 20 {mu}m rms. Reproduction of the high precision assembly of the detector is thus guaranteed. (orig.).

  17. High-Precision Phenotyping of Grape Bunch Architecture Using Fast 3D Sensor and Automation.

    Science.gov (United States)

    Rist, Florian; Herzog, Katja; Mack, Jenny; Richter, Robert; Steinhage, Volker; Töpfer, Reinhard

    2018-03-02

    Wine growers prefer cultivars with looser bunch architecture because of the decreased risk for bunch rot. As a consequence, grapevine breeders have to select seedlings and new cultivars with regard to appropriate bunch traits. Bunch architecture is a mosaic of different single traits which makes phenotyping labor-intensive and time-consuming. In the present study, a fast and high-precision phenotyping pipeline was developed. The optical sensor Artec Spider 3D scanner (Artec 3D, L-1466, Luxembourg) was used to generate dense 3D point clouds of grapevine bunches under lab conditions and an automated analysis software called 3D-Bunch-Tool was developed to extract different single 3D bunch traits, i.e., the number of berries, berry diameter, single berry volume, total volume of berries, convex hull volume of grapes, bunch width and bunch length. The method was validated on whole bunches of different grapevine cultivars and phenotypic variable breeding material. Reliable phenotypic data were obtained which show high significant correlations (up to r² = 0.95 for berry number) compared to ground truth data. Moreover, it was shown that the Artec Spider can be used directly in the field where achieved data show comparable precision with regard to the lab application. This non-invasive and non-contact field application facilitates the first high-precision phenotyping pipeline based on 3D bunch traits in large plant sets.

  18. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Z., E-mail: zhaohui@nwpu.edu.cn; Yu, T. [School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072 (China); Chen, H. [Xi’an Aerospace Propulsion Institute, Xi’an 710100 (China); Li, B. [State Key Laboratory for Manufacturing and Systems Engineering, Xi’an Jiaotong University, Xi’an 710054 (China)

    2016-08-15

    The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software TEMA Motion is used to track the spot which marked the cage surface. Finally, by developing the MATLAB program, a Lissajous’ figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

  19. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

    International Nuclear Information System (INIS)

    Yang, Z.; Yu, T.; Chen, H.; Li, B.

    2016-01-01

    The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software TEMA Motion is used to track the spot which marked the cage surface. Finally, by developing the MATLAB program, a Lissajous’ figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

  20. High precision locations of long-period events at La Fossa Crater (Vulcano Island, Italy

    Directory of Open Access Journals (Sweden)

    Salvatore Rapisarda

    2009-06-01

    Full Text Available Since the last eruption in 1888-90, the volcanic activity on Vulcano Island (Aeolian Archipelago, Italy has been limited to fumarolic degassing. Fumaroles are mainly concentred at the active cone of La Fossa in the northern sector of the island and are periodically characterized by increases in temperature as well as in the amount of both CO2 and He. Seismic background activity at Vulcano is dominated by micro-seismicity originating at shallow depth (<1-1.5 km under La Fossa cone. This seismicity is related to geothermal system processes and comprises long period (LP events. LPs are generally considered as the resonance of a fluid-filled volume in response to a trigger. We analyzed LP events recorded during an anomalous degassing period (August-October 2006 applying a high precision technique to define the shape of the trigger source. Absolute and high precision locations suggest that LP events recorded at Vulcano during 2006 were produced by a shallow focal zone ca. 200 m long, 40 m wide and N30-40E oriented. Their occurrence is linked to magmatic fluid inputs that by modifying the hydrothermal system cause excitation of a fluid-filled cavity.

  1. MATS and LaSpec: High-precision experiments using ion traps and lasers at FAIR

    Science.gov (United States)

    Rodríguez, D.; Blaum, K.; Nörtershäuser, W.; Ahammed, M.; Algora, A.; Audi, G.; Äystö, J.; Beck, D.; Bender, M.; Billowes, J.; Block, M.; Böhm, C.; Bollen, G.; Brodeur, M.; Brunner, T.; Bushaw, B. A.; Cakirli, R. B.; Campbell, P.; Cano-Ott, D.; Cortés, G.; Crespo López-Urrutia, J. R.; Das, P.; Dax, A.; de, A.; Delheij, P.; Dickel, T.; Dilling, J.; Eberhardt, K.; Eliseev, S.; Ettenauer, S.; Flanagan, K. T.; Ferrer, R.; García-Ramos, J.-E.; Gartzke, E.; Geissel, H.; George, S.; Geppert, C.; Gómez-Hornillos, M. B.; Gusev, Y.; Habs, D.; Heenen, P.-H.; Heinz, S.; Herfurth, F.; Herlert, A.; Hobein, M.; Huber, G.; Huyse, M.; Jesch, C.; Jokinen, A.; Kester, O.; Ketelaer, J.; Kolhinen, V.; Koudriavtsev, I.; Kowalska, M.; Krämer, J.; Kreim, S.; Krieger, A.; Kühl, T.; Lallena, A. M.; Lapierre, A.; Le Blanc, F.; Litvinov, Y. A.; Lunney, D.; Martínez, T.; Marx, G.; Matos, M.; Minaya-Ramirez, E.; Moore, I.; Nagy, S.; Naimi, S.; Neidherr, D.; Nesterenko, D.; Neyens, G.; Novikov, Y. N.; Petrick, M.; Plaß, W. R.; Popov, A.; Quint, W.; Ray, A.; Reinhard, P.-G.; Repp, J.; Roux, C.; Rubio, B.; Sánchez, R.; Schabinger, B.; Scheidenberger, C.; Schneider, D.; Schuch, R.; Schwarz, S.; Schweikhard, L.; Seliverstov, M.; Solders, A.; Suhonen, M.; Szerypo, J.; Taín, J. L.; Thirolf, P. G.; Ullrich, J.; van Duppen, P.; Vasiliev, A.; Vorobjev, G.; Weber, C.; Wendt, K.; Winkler, M.; Yordanov, D.; Ziegler, F.

    2010-05-01

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. The mass and its inherent connection with the nuclear binding energy is a fundamental property of a nuclide, a unique “fingerprint”. Thus, precise mass values are important for a variety of applications, ranging from nuclear-structure studies like the investigation of shell closures and the onset of deformation, tests of nuclear mass models and mass formulas, to tests of the weak interaction and of the Standard Model. The required relative accuracy ranges from 10-5 to below 10-8 for radionuclides, which most often have half-lives well below 1 s. Substantial progress in Penning trap mass spectrometry has made this method a prime choice for precision measurements on rare isotopes. The technique has the potential to provide high accuracy and sensitivity even for very short-lived nuclides. Furthermore, ion traps can be used for precision decay studies and offer advantages over existing methods. With MATS (Precision Measurements of very short-lived nuclei using an A_dvanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10-9 can be reached by employing highly-charged ions and a non

  2. Long-lasting Cadomian magmatic activity along an active northern Gondwana margin: U-Pb zircon and Sr-Nd isotopic evidence from the Brunovistulian Domain, eastern Bohemian Massif

    Science.gov (United States)

    Soejono, Igor; Janoušek, Vojtěch; Žáčková, Eliška; Sláma, Jiří; Konopásek, Jiří; Machek, Matěj; Hanžl, Pavel

    2017-09-01

    Cadomian magmatic complexes of the Brunovistulian Domain crop out at the eastern termination of the Bohemian Massif. However, the age, nature and geotectonic affinity of some of pre-Variscan (meta-)igneous rock complexes from this domain are still unknown. Geochronological and geochemical study of the granitic rocks across the Brunovistulian Domain reveals new information about the timing and nature of this magmatic activity originally situated along the northern margin of Gondwana. Zircon U-Pb data (601 ± 3 Ma, Brno Massif; 634 ± 6 Ma, paraautochtonous core of the Svratka Dome; 568 ± 3 Ma, Bíteš orthogneiss) from the allochtonous Moravicum indicate the prolonged magmatic activity within the Brunovistulian Domain during the Ediacaran. The major- and trace-element and Sr-Nd isotopic signatures show heterogeneous geochemical characteristics of the granitic rocks and suggest a magmatic-arc geotectonic setting. The two-stage Depleted Mantle Nd model ages ( c. 1.3-2.0 Ga) indicate derivation of the granitic rocks from a relatively primitive crustal source, as well as from an ancient and evolved continental crust of the Brunovistulian Domain. These results constrain the magmatic-arc activity to c. 635-570 Ma and provide a further evidence for a long-lived (at least c. 65 Myr) and likely episodic subduction-related magmatism at the northern margin of Gondwana. The presence of granitic intrusions derived from variously mature crustal sources at different times suggests heterogeneous crustal segments to having been involved in the magmatic-arc system during its multistage evolution.

  3. Late Jurassic-Early Cretaceous episodic development of the Bangong Meso-Tethyan subduction: Evidence from elemental and Sr-Nd isotopic geochemistry of arc magmatic rocks, Gaize region, central Tibet, China

    Science.gov (United States)

    Zhang, Yu-Xiu; Li, Zhi-Wu; Yang, Wen-Guang; Zhu, Li-Dong; Jin, Xin; Zhou, Xiao-Yao; Tao, Gang; Zhang, Kai-Jun

    2017-03-01

    The Bangong Meso-Tethys plays a critical role in the development of the Tethyan realm and the initial elevation of the Tibetan Plateau. However, its precise subduction polarity, and history still remain unclear. In this study, we synthesize a report for the Late Jurassic-Early Cretaceous two-phase magmatic rocks in the Gaize region at the southern margin of the Qiangtang block located in central Tibet. These rocks formed during the Late Jurassic-earliest Cretaceous (161-142 Ma) and Early Cretaceous (128-106 Ma), peaking at 146 Ma and 118 Ma, respectively. The presence of inherited zircons indicates that an Archean component exists in sediments in the shallow Qiangtang crust, and has a complex tectonomagmatic history. Geochemical and Sr-Nd isotopic data show that the two-phase magmatic rocks exhibit characteristics of arc magmatism, which are rich in large-ion incompatible elements (LIIEs), but are strongly depleted in high field strength elements (HFSEs). The Late Jurassic-earliest Cretaceous magmatic rocks mixed and mingled among mantle-derived mafic magmas, subduction-related sediments, or crustally-derived felsic melts and fluids, formed by a northward and steep subduction of the Bangong Meso-Tethys ocean crust. The magmatic gap at 142-128 Ma marks a flat subduction of the Meso-Tethys. The Early Cretaceous magmatism experienced a magma MASH (melting, assimilation, storage, and homogenization) process among mantle-derived mafic magmas, or crustally-derived felsic melts and fluids, as a result of the Meso-Tethys oceanic slab roll-back, which triggered simultaneous back-arc rifting along the southern Qiangtang block margin.

  4. Trace-element and Nd-isotope systematics in detrital apatite of the Po river catchment: Implications for provenance discrimination and the lag-time approach to detrital thermochronology

    Science.gov (United States)

    Malusà, Marco G.; Wang, Jiangang; Garzanti, Eduardo; Liu, Zhi-Chao; Villa, Igor M.; Wittmann, Hella

    2017-10-01

    Detrital thermochronology is often employed to assess the evolutionary stage of an entire orogenic belt using the lag-time approach, i.e., the difference between the cooling and depositional ages of detrital mineral grains preserved in a stratigraphic succession. The impact of different eroding sources to the final sediment sink is controlled by several factors, including the short-term erosion rate and the mineral fertility of eroded bedrock. Here, we use apatite fertility data and cosmogenic-derived erosion rates in the Po river catchment (Alps-Apennines) to calculate the expected percentage of apatite grains supplied to the modern Po delta from the major Alpine and Apenninic eroding sources. We test these predictions by using a cutting-edge dataset of trace-element and Nd-isotope signatures on 871 apatite grains from 14 modern sand samples, and we use apatite fission-track data to validate our geochemical approach to provenance discrimination. We found that apatite grains shed from different sources are geochemically distinct. Apatites from the Lepontine dome in the Central Alps show relative HREE enrichment, lower concentrations in Ce and U, and higher 147Sm/144Nd ratios compared to apatites derived from the External Massifs. Derived provenance budgets point to a dominant apatite contribution to the Po delta from the high-fertility Lepontine dome, consistent with the range independently predicted from cosmonuclide and mineral-fertility data. Our results demonstrate that the single-mineral record in the final sediment sink can be largely determined by high-fertility source rocks exposed in rapidly eroding areas within the drainage. This implies that the detrital thermochronology record may reflect processes affecting relatively small parts of the orogenic system under consideration. A reliable approach to lag-time analysis would thus benefit from an independent provenance discrimination of dated mineral grains, which may allow to proficiently reconsider many

  5. Geochemistry, geochronology and Nd isotopes of the Gogó da Onça Granite: A new Paleoproterozoic A-type granite of Carajás Province, Brazil

    Science.gov (United States)

    Teixeira, Mayara Fraeda Barbosa; Dall'Agnol, Roberto; Santos, João Orestes Schneider; de Sousa, Luan Alexandre Martins; Lafon, Jean-Michel

    2017-12-01

    The Gogó da Onça Granite (GOG) comprise a stock located in the Carajás Province in the southeastern part of Amazonian Craton near its border with the Araguaia Belt. Three facies were identified in the pluton: biotite-amphibole granodiorite, biotite-amphibole monzogranite and amphibole-biotite syenogranite. The GGO crosscut discordantly the Archean country rocks and are not foliated. All Gogó da Onça Granite varieties are metaluminous, ferroan A2-subtype granites with reduced character. The major and trace element behavior suggests that its different facies are related by fractional crystallization. Zircon and titanite U-Pb SHRIMP ages show that the pluton crystallized at ∼1880-1870 Ma and is related to the remarkable Paleoproterozoic magmatic event identified in the Carajás Province. Whole-rock Nd isotope data (TDM ages 2.78 to 2.81, εNd values of -9.07 to -9.48) indicate that the GOG magmas derived from an Archaean source compatible with that of some other Paleoproterozoic suites from Carajás Province. The GOG show significant contrasts with the Jamon and Velho Guilherme Paleoproterozoic suites from Carajás Province and the inclusion of the Gogó da Onça granite in any of these suites is not justified. The GOG is more akin to the Serra dos Carajás Suite and to the Seringa and São João granites of Carajás and to the Mesoproterozoic Sherman granite of USA and the Paleoproterozoic Suomenniemi Batholith of Finland. This study puts in evidence the relevance of precise geochronological data and estimation of magma oxidation state in the characterization and correlation of A-type granites.

  6. A New High-Precision Correction Method of Temperature Distribution in Model Stellar Atmospheres

    Directory of Open Access Journals (Sweden)

    Sapar A.

    2013-06-01

    Full Text Available The main features of the temperature correction methods, suggested and used in modeling of plane-parallel stellar atmospheres, are discussed. The main features of the new method are described. Derivation of the formulae for a version of the Unsöld-Lucy method, used by us in the SMART (Stellar Model Atmospheres and Radiative Transport software for modeling stellar atmospheres, is presented. The method is based on a correction of the model temperature distribution based on minimizing differences of flux from its accepted constant value and on the requirement of the lack of its gradient, meaning that local source and sink terms of radiation must be equal. The final relative flux constancy obtainable by the method with the SMART code turned out to have the precision of the order of 0.5 %. Some of the rapidly converging iteration steps can be useful before starting the high-precision model correction. The corrections of both the flux value and of its gradient, like in Unsöld-Lucy method, are unavoidably needed to obtain high-precision flux constancy. A new temperature correction method to obtain high-precision flux constancy for plane-parallel LTE model stellar atmospheres is proposed and studied. The non-linear optimization is carried out by the least squares, in which the Levenberg-Marquardt correction method and thereafter additional correction by the Broyden iteration loop were applied. Small finite differences of temperature (δT/T = 10−3 are used in the computations. A single Jacobian step appears to be mostly sufficient to get flux constancy of the order 10−2 %. The dual numbers and their generalization – the dual complex numbers (the duplex numbers – enable automatically to get the derivatives in the nilpotent part of the dual numbers. A version of the SMART software is in the stage of refactorization to dual and duplex numbers, what enables to get rid of the finite differences, as an additional source of lowering precision of the

  7. New Sm-Nd isotopic data from the Southern Aracuai-Ribeira belt: Parabaiba Do Sul group and associated granitic intrusions

    International Nuclear Information System (INIS)

    Medeiros, Silvia Regina de; Wiedemann, Cristina Maria

    2001-01-01

    The Aracuai-Ribeira belt is a Neoproterozoic orogenic belt extending along the Brazilian Coast, bordering the eastern margin of the Sao Francisco craton (Pedrosa Soares et al., in press). In this work we start unveiling the magmatic source characteristics of the southern Espirito Santo segment of this belt through the use of new Sm-Nd data were obtained from exactly the same sample which Sollner et al. (1991), took their U-Pb and Rb-Sr measurements (the major isotopic informations available up to now) allowing thus a correlation with this previous geochronologic work, contributing for an improvement of the evolution model of the whole belt (au)

  8. A new approach to the BFKL mechanism. Application to high-precision HERA data

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, H. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Lipatov, L.N. [Sankt-Peterburgskij Univ., St. Petersburg (Russian Federation); Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Ross, D.A. [Southampton Univ. (United Kingdom). School of Physics and Astronomy; Schulz, O. [Max Planck Institute for Physics, Munich (Germany)

    2017-07-15

    We analyse here in NLO the physical properties of the discrete eigenvalue solution for the BFKL equation. We show that a set of positive ω eigenfunctions together with a small contribution from a continuum of negative ω's provide an excellent description of high-precision HERA F{sub 2} data in the region, x < 0.001, Q{sup 2} > 6 GeV{sup 2}. The phases of the eigenfunctions can be obtained from a simple parametrisation of the pomeron spectrum, which has a natural motivation within BFKL. The data analysis shows that the first eigenfunction decouples or nearly decouples from the proton. This suggests that there exist an additional ground state, which has no nodes.

  9. Decoupling of the leading contribution in the discrete BFKL analysis of high-precision HERA data

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, H. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Lipatov, L.N. [St. Petersburg State University, St. Petersburg (Russian Federation); Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Ross, D.A. [University of Southampton, School of Physics and Astronomy, Southampton (United Kingdom); Schulz, O. [Max Planck Institute for Physics, Munich (Germany)

    2017-11-15

    We analyse, in NLO, the physical properties of the discrete eigenvalue solution for the BFKL equation. We show that a set of eigenfunctions with positive eigenvalues, ω, together with a small contribution from a continuum of eigenfunctions with negative ω, provide an excellent description of high-precision HERA F{sub 2} data in the region, x < 0.001, Q{sup 2} > 6 GeV{sup 2}. The phases of the eigenfunctions can be obtained from a simple parametrisation of the pomeron spectrum, which has a natural motivation within BFKL. The data analysis shows that the first eigenfunction decouples completely or almost completely from the proton. This suggests that there exists an additional ground state, which is naturally saturated and may have the properties of the soft pomeron. (orig.)

  10. High-precision soft x-ray polarimeter at Diamond Light Source.

    Science.gov (United States)

    Wang, H; Dhesi, S S; Maccherozzi, F; Cavill, S; Shepherd, E; Yuan, F; Deshmukh, R; Scott, S; van der Laan, G; Sawhney, K J S

    2011-12-01

    The development and performance of a high-precision polarimeter for the polarization analysis in the soft x-ray region is presented. This versatile, high-vacuum compatible instrument is supported on a hexapod to simplify the alignment with a resolution less than 5 μrad, and can be moved with its own independent control system easily between different beamlines and synchrotron facilities. The polarimeter can also be used for the characterization of reflection and transmission properties of optical elements. A W/B(4)C multilayer phase retarder was used to characterize the polarization state up to 1200 eV. A fast and accurate alignment procedure was developed, and complete polarization analysis of the APPLE II undulator at 712 eV has been performed.

  11. A six-bank multi-leaf system for high precision shaping of large fields

    International Nuclear Information System (INIS)

    Topolnjak, R; Heide, U A van der; Raaymakers, B W; Kotte, A N T J; Welleweerd, J; Lagendijk, J J W

    2004-01-01

    In this study, we present the design for an alternative MLC system that allows high precision shaping of large fields. The MLC system consists of three layers of two opposing leaf banks. The layers are rotated 60 deg. relative to each other. The leaves in each bank have a standard width of 1 cm projected at the isocentre. Because of the symmetry of the collimator set-up it is expected that collimator rotation will not be required, thus simplifying the construction considerably. A 3D ray tracing computer program was developed in order to simulate the fluence profile for a given collimator and used to optimize the design and investigate its performance. The simulations show that a six-bank collimator will afford field shaping of fields of about 40 cm diameter with a precision comparable to that of existing mini MLCs with a leaf width of 4 mm

  12. The LPCTrap facility: A novel transparent Paul trap for high-precision experiments

    International Nuclear Information System (INIS)

    Rodriguez, D.; Mery, A.; Ban, G.; Bregeault, J.; Darius, G.; Durand, D.; Flechard, X.; Herbane, M.; Labalme, M.; Lienard, E.; Mauger, F.; Merrer, Y.; Naviliat-Cuncic, O.; Thomas, J.C.; Vandamme, C.

    2006-01-01

    A trap system has been built to perform high-precision β-decay experiments. The system is coupled to the low-energy beam line of the SPIRAL source at GANIL. The continuous ion beam from SPIRAL with energies between 10 and 20keV is slowed down by means of a buffer-gas-filled RFQ trap and ejected thereafter as short ion bunches into a novel transparent Paul trap. Two pulsed cavities located downstream from the RFQ reduce the energy of the ion bunch down to about a hundred eV for an efficient capture in the Paul trap. We describe here the complete system along with the first results obtained with stable He+4, Cl+35 and Ar+36,40 ions from the SPIRAL ECR source. An overall efficiency of 8.7(8)x10 -4 is achieved for 4 He + ions under specific conditions

  13. Moving Object Detection Using Scanning Camera on a High-Precision Intelligent Holder

    Science.gov (United States)

    Chen, Shuoyang; Xu, Tingfa; Li, Daqun; Zhang, Jizhou; Jiang, Shenwang

    2016-01-01

    During the process of moving object detection in an intelligent visual surveillance system, a scenario with complex background is sure to appear. The traditional methods, such as “frame difference” and “optical flow”, may not able to deal with the problem very well. In such scenarios, we use a modified algorithm to do the background modeling work. In this paper, we use edge detection to get an edge difference image just to enhance the ability of resistance illumination variation. Then we use a “multi-block temporal-analyzing LBP (Local Binary Pattern)” algorithm to do the segmentation. In the end, a connected component is used to locate the object. We also produce a hardware platform, the core of which consists of the DSP (Digital Signal Processor) and FPGA (Field Programmable Gate Array) platforms and the high-precision intelligent holder. PMID:27775671

  14. Moving Object Detection Using Scanning Camera on a High-Precision Intelligent Holder

    Directory of Open Access Journals (Sweden)

    Shuoyang Chen

    2016-10-01

    Full Text Available During the process of moving object detection in an intelligent visual surveillance system, a scenario with complex background is sure to appear. The traditional methods, such as “frame difference” and “optical flow”, may not able to deal with the problem very well. In such scenarios, we use a modified algorithm to do the background modeling work. In this paper, we use edge detection to get an edge difference image just to enhance the ability of resistance illumination variation. Then we use a “multi-block temporal-analyzing LBP (Local Binary Pattern” algorithm to do the segmentation. In the end, a connected component is used to locate the object. We also produce a hardware platform, the core of which consists of the DSP (Digital Signal Processor and FPGA (Field Programmable Gate Array platforms and the high-precision intelligent holder.

  15. Efficient high-precision matrix algebra on parallel architectures for nonlinear combinatorial optimization

    KAUST Repository

    Gunnels, John; Lee, Jon; Margulies, Susan

    2010-01-01

    We provide a first demonstration of the idea that matrix-based algorithms for nonlinear combinatorial optimization problems can be efficiently implemented. Such algorithms were mainly conceived by theoretical computer scientists for proving efficiency. We are able to demonstrate the practicality of our approach by developing