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Sample records for high precision radiometric

  1. Precision radiometric surface temperature (PRST) sensor

    NASA Astrophysics Data System (ADS)

    Daly, James T.; Roberts, Carson; Bodkin, Andrew; Sundberg, Robert; Beaven, Scott; Weinheimer, Jeffrey

    2013-05-01

    There is a need for a Precision Radiometric Surface Temperature (PRST) measurement capability that can achieve noncontact profiling of a sample's surface temperature when heated dynamically during laser processing, aerothermal heating or metal cutting/machining. Target surface temperature maps within and near the heated spot provide critical quantitative diagnostic data for laser-target coupling effectiveness and laser damage assessment. In the case of metal cutting, this type of measurement provides information on plastic deformation in the primary shear zone where the cutting tool is in contact with the workpiece. The challenge in these cases is to measure the temperature of a target while its surface's temperature and emissivity are changing rapidly and with incomplete knowledge of how the emissivity and surface texture (scattering) changes with temperature. Bodkin Design and Engineering, LLC (BDandE), with partners Spectral Sciences, Inc. (SSI) and Space Computer Corporation (SCC), has developed a PRST Sensor that is based on a hyperspectral MWIR imager spanning the wavelength range 2-5 μm and providing a hyperspectral datacube of 20-24 wavelengths at 60 Hz frame rate or faster. This imager is integrated with software and algorithms to extract surface temperature from radiometric measurements over the range from ambient to 2000K with a precision of 20K, even without a priori knowledge of the target's emissivity and even as the target emissivity may be changing with time and temperature. In this paper, we will present a description of the PRST system as well as laser heating test results which show the PRST system mapping target surface temperatures in the range 600-2600K on a variety of materials.

  2. Implementation of high precision optical and radiometric LRO tracking data in the orbit determination to supplement the baseline S-band tracking

    NASA Astrophysics Data System (ADS)

    Mao, D.; Torrence, M. H.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2016-12-01

    LRO has been in a polar lunar orbit for 7 year since it was launched in June 2009. Seven instruments are onboard LRO to perform a global and detailed geophysical, geological and geochemical mapping of the Moon, some of which have very high spatial resolution. To take full advantage of the high resolution LRO datasets from these instruments, the spacecraft orbit must be reconstructed precisely. The baseline LRO tracking was the NASA's White Sands station in New Mexico and a commercial network, the Universal Space Network (USN), providing up to 20 hours per day of almost continuous S-band radio frequency link to LRO. The USN stations produce S-band range data with a 0.4 m precision and Doppler data with a 0.8 mm/s precision. Using the S-band tracking data together with the high-resolution gravity field model from the GRAIL mission, definitive LRO orbit solutions are obtained with an accuracy of 10 m in total position and 0.5 m radially. Confirmed by the 0.50-m high-resolution NAC images from the LROC team, these orbits well represent the LRO orbit "truth". In addition to the S-band data, one-way Laser Ranging (LR) to LRO provides a unique LRO optical tracking dataset over 5 years, from June 2009 to September 2014. Ten international satellite laser ranging stations contributed over 4000 hours LR data with the 0.05 - 0.10 m normal point precision. Another set of high precision LRO tracking data is provided by the Deep Space Network (DSN), which produces radiometric tracking data more precise than the USN S-band data. In the last two years of the LRO mission, the temporal coverage of the USN data has decreased significantly. We show that LR and DSN data can be a good supplement to the baseline tracking data for the orbit reconstruction.

  3. Transportable high sensitivity small sample radiometric calorimeter

    SciTech Connect

    Wetzel, J.R.; Biddle, R.S.; Cordova, B.S.; Sampson, T.E.; Dye, H.R.; McDow, J.G.

    1998-12-31

    A new small-sample, high-sensitivity transportable radiometric calorimeter, which can be operated in different modes, contains an electrical calibration method, and can be used to develop secondary standards, will be described in this presentation. The data taken from preliminary tests will be presented to indicate the precision and accuracy of the instrument. The calorimeter and temperature-controlled bath, at present, require only a 30-in. by 20-in. tabletop area. The calorimeter is operated from a laptop computer system using unique measurement module capable of monitoring all necessary calorimeter signals. The calorimeter can be operated in the normal calorimeter equilibration mode, as a comparison instrument, using twin chambers and an external electrical calibration method. The sample chamber is 0.75 in (1.9 cm) in diameter by 2.5 in. (6.35 cm) long. This size will accommodate most {sup 238}Pu heat standards manufactured in the past. The power range runs from 0.001 W to <20 W. The high end is only limited by sample size.

  4. Precise quantitation of PAIgG: A new radiometric microtechnique

    SciTech Connect

    Schwartz, K.A.; Gauger, J.A.; Davis, J.M. )

    1990-03-01

    We report the development of a radiometric assay for platelet-bound IgG that is both sensitive and quantitative. The assay utilized 96-well millititer plates incorporating a 0.2 microns filter membrane in the bottom. A 125I-labeled monoclonal antihuman IgG, as a secondary antibody, detected the platelet-bound human IgG. Since 5 x 10(6) platelets were used for each assay, tests for platelet-bound IgG can be performed on persons with severe thrombocytopenia. For the detection of circulating antiplatelet alloantibodies, as little as 10 microliters of platelet-free plasma per assay is required. Antiplatelet IgG was quantitated by using anti-PIA1 antibody that was purified with affinity and elution and DEAE chromatography. This purified antiplatelet antibody was labeled with 125I and was used to determine the binding ratio of secondary antibody to primary antibody. Under our standard conditions, this ratio was found to be stable at approximately 0.35 over the sensitivity range of the assay. The assay can detect approximately 200 molecules of human IgG per platelet (0.1 ng of secondary antibody bound per 5 x 10(6) platelets). It has a linear range from 0 to 7,000 molecules per platelet. Quantitation of anti-PIA1 binding for platelets stored for up to 6 months under refrigeration showed no change in number of PIA1 binding sites. Clinical studies showed that 18 of 19 ITP patients had an increased number of IgG molecules per platelet as did patients with malignancy and drug-induced immune thrombocytopenia. Patients who had received multiple platelet transfusions had antiplatelet antibody in their plasma. Normal amounts of PAIgG were observed in platelets and plasma of patients with nonimmune thrombocytopenia.

  5. A high-throughput radiometric kinase assay

    PubMed Central

    Duong-Ly, Krisna C.; Peterson, Jeffrey R.

    2016-01-01

    Aberrant kinase signaling has been implicated in a number of diseases. While kinases have become attractive drug targets, only a small fraction of human protein kinases have validated inhibitors. Screening libraries of compounds against a kinase or kinases of interest is routinely performed during kinase inhibitor development to identify promising scaffolds for a particular target and to identify kinase targets for compounds of interest. Screening of more focused compound libraries may also be conducted in the later stages of inhibitor development to improve potency and optimize selectivity. The dot blot kinase assay is a robust, high-throughput kinase assay that can be used to screen a number of small molecule compounds against one kinase of interest or several kinases. Here, a protocol for a dot blot kinase assay used for measuring insulin receptor kinase activity is presented. This protocol can be readily adapted for use with other protein kinases. PMID:26501904

  6. High speed radiometric measurements of IED detonation fireballs

    NASA Astrophysics Data System (ADS)

    Spidell, Matthew T.; Gordon, J. Motos; Pitz, Jeremey; Gross, Kevin C.; Perram, Glen P.

    2010-04-01

    Continuum emission is predominant in fireball spectral phenomena and in some demonstrated cases, fine detail in the temporal evolution of infrared spectral emissions can be used to estimate size and chemical composition of the device. Recent work indicates that a few narrow radiometric bands may reveal forensic information needed for the explosive discrimination and classification problem, representing an essential step in moving from "laboratory" measurements to a rugged, fieldable system. To explore phenomena not observable in previous experiments, a high speed (10μs resolution) radiometer with four channels spanning the infrared spectrum observed the detonation of nine home made explosive (HME) devices in the < 100lb class. Radiometric measurements indicate that the detonation fireball is well approximated as a single temperature blackbody at early time (0 < t <~ 3ms). The effective radius obtained from absolute intensity indicates fireball growth at supersonic velocity during this time. Peak fireball temperatures during this initial detonation range between 3000.3500K. The initial temperature decay with time (t <~ 10ms) can be described by a simple phenomenological model based on radiative cooling. After this rapid decay, temperature exhibits a small, steady increase with time (10 <~ t <~ 50ms) and peaking somewhere between 1000.1500K-likely the result of post-detonation combustion-before subsequent cooling back to ambient conditions . Radius derived from radiometric measurements can be described well (R2 > 0.98) using blast model functional forms, suggesting that energy release could be estimated from single-pixel radiometric detectors. Comparison of radiometer-derived fireball size with FLIR infrared imagery indicate the Planckian intensity size estimates are about a factor of two smaller than the physical extent of the fireball.

  7. High Precision GPS Measurements

    DTIC Science & Technology

    2010-02-28

    GNSS Service (IGS) database, and magnetic field vectors from the International Geomagnetic Reference Field (IGRF) model [9]. These combined...Additonal correlations between the higher order range error and geomagnetic activity and seasonal variations are also obtained. Fig. 4 shows...clear correlation between the geomagnetic activity and enhanced higher order error at both sites. High Precision GPS Final Report Page 5 Fig.3

  8. High dynamic range infrared thermography by pixelwise radiometric self calibration

    NASA Astrophysics Data System (ADS)

    Ochs, M.; Schulz, A.; Bauer, H.-J.

    2010-03-01

    A procedure is described where the response function of each pixel of an InSb detector is determined by radiometric self-calibration. With the present approach no knowledge of the spectral characteristics of the IR system is required to recover a quantity which is linear with the incident irradiance of the object. The inherent detector non-uniformity is corrected on the basis of self-calibrated scaled irradiance. Compared to the standard two-point non-uniformity correction procedure - performed with the detector signal - only two NUC-tables are required for arbitrary integration times. Images obtained at various exposures are fused to a single high dynamic range image. The procedure is validated with synthetic data and its performance is demonstrated by measurements performed with a high resolution InSb FPA.

  9. High precision applications of the global positioning system

    NASA Technical Reports Server (NTRS)

    Lichten, Stephen M.

    1991-01-01

    The Global Positioning System (GPS) is a constellation of U.S. defense navigation satellites which can be used for military and civilian positioning applications. A wide variety of GPS scientific applications were identified and precise positioning capabilities with GPS were already demonstrated with data available from the present partial satellite constellation. Expected applications include: measurements of Earth crustal motion, particularly in seismically active regions; measurements of the Earth's rotation rate and pole orientation; high-precision Earth orbiter tracking; surveying; measurements of media propagation delays for calibration of deep space radiometric data in support of NASA planetary missions; determination of precise ground station coordinates; and precise time transfer worldwide.

  10. Radiometric Calibration Assessment of Commercial High Spatial Resolution Multispectral Image Products

    NASA Technical Reports Server (NTRS)

    Holekamp, Kara; Aaron, David; Thome, Kurtis

    2006-01-01

    Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities can better understand their properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, satellite at-sensor radiance values were compared to those estimated by each independent team member to determine the sensor's radiometric accuracy. The combined results of this evaluation provide the user community with an independent assessment of these commercially available high spatial resolution sensors' absolute calibration values.

  11. High precision redundant robotic manipulator

    DOEpatents

    Young, Kar-Keung David

    1998-01-01

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degreed 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.

  12. High precision redundant robotic manipulator

    DOEpatents

    Young, K.K.D.

    1998-09-22

    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. High precision anatomy for MEG.

    PubMed

    Troebinger, Luzia; López, José David; Lutti, Antoine; Bradbury, David; Bestmann, Sven; Barnes, Gareth

    2014-02-01

    Precise MEG estimates of neuronal current flow are undermined by uncertain knowledge of the head location with respect to the MEG sensors. This is either due to head movements within the scanning session or systematic errors in co-registration to anatomy. Here we show how such errors can be minimized using subject-specific head-casts produced using 3D printing technology. The casts fit the scalp of the subject internally and the inside of the MEG dewar externally, reducing within session and between session head movements. Systematic errors in matching to MRI coordinate system are also reduced through the use of MRI-visible fiducial markers placed on the same cast. Bootstrap estimates of absolute co-registration error were of the order of 1mm. Estimates of relative co-registration error were <1.5mm between sessions. We corroborated these scalp based estimates by looking at the MEG data recorded over a 6month period. We found that the between session sensor variability of the subject's evoked response was of the order of the within session noise, showing no appreciable noise due to between-session movement. Simulations suggest that the between-session sensor level amplitude SNR improved by a factor of 5 over conventional strategies. We show that at this level of coregistration accuracy there is strong evidence for anatomical models based on the individual rather than canonical anatomy; but that this advantage disappears for errors of greater than 5mm. This work paves the way for source reconstruction methods which can exploit very high SNR signals and accurate anatomical models; and also significantly increases the sensitivity of longitudinal studies with MEG. © 2013. Published by Elsevier Inc. All rights reserved.

  14. The absolute radiometric calibration of the advanced very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    Slater, P. N.; Teillet, P. M.; Mao, Y.

    1987-01-01

    The early results of an absolute radiometric calibration of the NOAA-9 AVHRR sensor indicate significant degradations in the response of bands 1 and 2 compared to prelaunch values. The results are currently in the process of being verified and it may be that refinements of the methodology will be in order as additional data sets are analyzed. The LANDSAT TM calibration used in this approach is known to be very precise and the Herman radiative transfer code, supplemented by the 5-S code for gaseous transmission, is reliable as well. The extent to which other steps in the analysis procedure give rise to uncertainties in the results is currently under investigation. Particular attention is being given to the geometric matching of the AVHRR and TM imagery, as well as to the spectral redistribution procedure. By taking advantage of a reasonably precise calibration of TM imagery acquired on the same day as the AVHRR data at White Sands, a promising approach to the in-orbit calibration of AVHRR sensors is being developed. Current efforts involve primarily the examination of additional test cases and the investigation of possible simplifications in the procedure through judicious use of atmospheric models.

  15. Highly Parallel, High-Precision Numerical Integration

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2005-04-22

    This paper describes a scheme for rapidly computing numerical values of definite integrals to very high accuracy, ranging from ordinary machine precision to hundreds or thousands of digits, even for functions with singularities or infinite derivatives at endpoints. Such a scheme is of interest not only in computational physics and computational chemistry, but also in experimental mathematics, where high-precision numerical values of definite integrals can be used to numerically discover new identities. This paper discusses techniques for a parallel implementation of this scheme, then presents performance results for 1-D and 2-D test suites. Results are also given for a certain problem from mathematical physics, which features a difficult singularity, confirming a conjecture to 20,000 digit accuracy. The performance rate for this latter calculation on 1024 CPUs is 690 Gflop/s. We believe that this and one other 20,000-digit integral evaluation that we report are the highest-precision non-trivial numerical integrations performed to date.

  16. Radiometric correction procedure study

    NASA Technical Reports Server (NTRS)

    Colby, C.; Sands, R.; Murphrey, S.

    1978-01-01

    A comparison of MSS radiometric processing techniques identified as a preferred radiometric processing technique a procedure which equalizes the mean and standard deviation of detector-specific histograms of uncalibrated scene data. Evaluation of MSS calibration data demonstrated that the relationship between detector responses is essentially linear over the range of intensities typically observed in MSS data, and that the calibration wedge data possess a high degree of temporal stability. An analysis of the preferred radiometric processing technique showed that it could be incorporated into the MDP-MSS system without a major redesign of the system, and with minimal impact on system throughput.

  17. High precision triangular waveform generator

    DOEpatents

    Mueller, Theodore R.

    1983-01-01

    An ultra-linear ramp generator having separately programmable ascending and descending ramp rates and voltages is provided. Two constant current sources provide the ramp through an integrator. Switching of the current at current source inputs rather than at the integrator input eliminates switching transients and contributes to the waveform precision. The triangular waveforms produced by the waveform generator are characterized by accurate reproduction and low drift over periods of several hours. The ascending and descending slopes are independently selectable.

  18. High precision modeling for fundamental physics experiments

    NASA Astrophysics Data System (ADS)

    Rievers, Benny; Nesemann, Leo; Costea, Adrian; Andres, Michael; Stephan, Ernst P.; Laemmerzahl, Claus

    With growing experimental accuracies and high precision requirements for fundamental physics space missions the needs for accurate numerical modeling techniques are increasing. Motivated by the challenge of length stability in cavities and optical resonators we propose the develop-ment of a high precision modeling tool for the simulation of thermomechanical effects up to a numerical precision of 10-20 . Exemplary calculations for simplified test cases demonstrate the general feasibility of high precision calculations and point out the high complexity of the task. A tool for high precision analysis of complex geometries will have to use new data types, advanced FE solver routines and implement new methods for the evaluation of numerical precision.

  19. High Precision Laser Range Sensor

    NASA Technical Reports Server (NTRS)

    Dubovitsky, Serge (Inventor); Lay, Oliver P. (Inventor)

    2003-01-01

    The present invention is an improved distance measuring interferometer that includes high speed phase modulators and additional phase meters to generate and analyze multiple heterodyne signal pairs with distinct frequencies. Modulation sidebands with large frequency separation are generated by the high speed electro-optic phase modulators, requiring only a single frequency stable laser source and eliminating the need for a fist laser to be tuned or stabilized relative to a second laser. The combination of signals produced by the modulated sidebands is separated and processed to give the target distance. The resulting metrology apparatus enables a sensor with submicron accuracy or better over a multi- kilometer ambiguity range.

  20. High precision thermal neutron detectors

    SciTech Connect

    Radeka, V.; Schaknowski, N.A.; Smith, G.C.; Yu, B.

    1994-12-31

    Two-dimensional position sensitive detectors are indispensable in neutron diffraction experiments for determination of molecular and crystal structures in biology, solid-state physics and polymer chemistry. Some performance characteristics of these detectors are elementary and obvious, such as the position resolution, number of resolution elements, neutron detection efficiency, counting rate and sensitivity to gamma-ray background. High performance detectors are distinguished by more subtle characteristics such as the stability of the response (efficiency) versus position, stability of the recorded neutron positions, dynamic range, blooming or halo effects. While relatively few of them are needed around the world, these high performance devices are sophisticated and fairly complex, their development requires very specialized efforts. In this context, we describe here a program of detector development, based on {sup 3}He filled proportional chambers, which has been underway for some years at the Brookhaven National Laboratory. Fundamental approaches and practical considerations are outlined that have resulted in a series of high performance detectors with the best known position resolution, position stability, uniformity of response and reliability over time, for devices of this type.

  1. High-throughput radiometric CYP2C19 inhibition assay using tritiated (S)-mephenytoin.

    PubMed

    Di Marco, Annalise; Cellucci, Antonella; Chaudhary, Ashok; Fonsi, Massimiliano; Laufer, Ralph

    2007-10-01

    A rapid and sensitive radiometric assay for assessing the potential of drugs to inhibit cytochrome P450 (P450) 2C19 in human liver microsomes is described. The new assay, which does not require high-performance liquid chromatography (HPLC) separation or mass spectrometric detection, is based on the release of tritium as tritiated water that occurs upon CYP2C19-mediated 4'-hydroxylation of (S)-mephenytoin labeled with tritium in the 4' position. Because this reaction is subject to an NIH shift, tritium was also introduced into the 3'- and 5'-positions of the tracer to enhance formation of a tritiated water product. Tritiated water was separated from the substrate using 96-well solid-phase extraction plates. The reaction is NADPH-dependent and sensitive to CYP2C19 inhibitors. IC(50) values for 15 diverse drugs differed less than 2.5-fold from those determined by quantification of the unlabeled 4'-hydroxy-(S)-mephenytoin product, using HPLC coupled to mass spectrometric detection. All of the steps of the new assay, namely incubation, product separation, and radioactivity counting, are performed in a 96-well format and can be automated. This assay represents a non-HPLC, high-throughput version of the classic (S)-mephenytoin 4'-hydroxylation assay, which is the most widely used method to assess the potential for CYP2C19 inhibition of new chemical entities.

  2. High precision neutron inelastic cross section measurements

    NASA Astrophysics Data System (ADS)

    Olacel, A.; Belloni, F.; Borcea, C.; Boromiza, M.; Dessagne, Ph.; Henning, G.; Kerveno, M.; Negret, A.; Nyman, M.; Pirovano, E.; Plompen, A.

    2017-06-01

    High precision neutron inelastic scattering cross section data are very important for the development of the new generation of nuclear reactors (Gen IV). Our experiments, performed using the GELINA neutron source and the GAINS spectrometer of the European Commission Joint Research Center, Geel, produce highly reliable and precise cross section data. We will present the details of the setup and the data analysis technique allowing production of such unique results, and we will show examples of two experimental results.

  3. The absolute radiometric calibration of the advanced very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    Slater, P. N.; Teillet, P. M.; Ding, Y.

    1988-01-01

    An increasing number of remote sensing investigations require radiometrically calibrated imagery from NOAA Advanced Very High Resolution Radiation (AVHRR) sensors. Although a prelaunch calibration is done for these sensors, there is no capability for monitoring any changes in the in-flight absolute calibration for the visible and near infrared spectral channels. Hence, the possibility of using the reflectance-based method developed at White Sands for in-orbit calibration of LANDSAT Thematic Mapper (TM) and SPOT Haute Resolution Visible (HVR) data to calibrate the AVHRR sensor was investigated. Three diffrent approaches were considered: Method 1 - ground and atmospheric measurements and reference to another calibrated satellite sensor; Method 2 - ground and atmospheric measurements with no reference to another sensor; and Method 3 - no ground and atmospheric measurements but reference to another satellite sensor. The purpose is to describe an investigation on the use of Method 2 to calibrate NOAA-9 AVHRR channels 1 and 2 with the help of ground and atmospheric measurements at Rogers (dry) Lake, Edwards Air Force Base (EAFB) in the Mojave desert of California.

  4. Precision Crystal Calorimeters in High Energy Physics

    ScienceCinema

    Ren-Yuan Zhu

    2016-07-12

    Precision crystal calorimeters traditionally play an important role in high energy physics experiments. In the last two decades, it faces a challenge to maintain its precision in a hostile radiation environment. This paper reviews the performance of crystal calorimeters constructed for high energy physics experiments and the progress achieved in understanding crystal’s radiation damage as well as in developing high quality scintillating crystals for particle physics. Potential applications of new generation scintillating crystals of high density and high light yield, such as LSO and LYSO, in particle physics experiments is also discussed.

  5. Radiometric Calibration of Mars HiRISE High Resolution Imagery Based on Fpga

    NASA Astrophysics Data System (ADS)

    Hou, Yifan; Geng, Xun; Xing, Shuai; Tang, Yonghe; Xu, Qing

    2016-06-01

    Due to the large data amount of HiRISE imagery, traditional radiometric calibration method is not able to meet the fast processing requirements. To solve this problem, a radiometric calibration system of HiRISE imagery based on field program gate array (FPGA) is designed. The montage gap between two channels caused by gray inconsistency is removed through histogram matching. The calibration system is composed of FPGA and DSP, which makes full use of the parallel processing ability of FPGA and fast computation as well as flexible control characteristic of DSP. Experimental results show that the designed system consumes less hardware resources and the real-time processing ability of radiometric calibration of HiRISE imagery is improved.

  6. High-precision arithmetic in mathematical physics

    DOE PAGES

    Bailey, David H.; Borwein, Jonathan M.

    2015-05-12

    For many scientific calculations, particularly those involving empirical data, IEEE 32-bit floating-point arithmetic produces results of sufficient accuracy, while for other applications IEEE 64-bit floating-point is more appropriate. But for some very demanding applications, even higher levels of precision are often required. Furthermore, this article discusses the challenge of high-precision computation, in the context of mathematical physics, and highlights what facilities are required to support future computation, in light of emerging developments in computer architecture.

  7. High precision phase-shifting electron holography

    PubMed

    Yamamoto; Kawajiri; Tanji; Hibino; Hirayama

    2000-01-01

    Today's information-oriented society requires high density and high quality magnetic recording media. The quantitative observation of fine magnetic structures by electron holography is greatly anticipated in the development of such new recording materials. However, the magnetic fields around particles <50 nm have not been observed, because the fields are too weak to observe in the usual way. Here we present a highly precise phase measurement technique: improved phase-shifting electron holography. Using this method, the electric field around a charged polystyrene latex particle (100 nm in diameter) and the magnetic field around iron particles (30 nm in diameter) are observed precisely. A precision of the reconstructed phase image of 2pi/300 rad is achieved in the image of the latex particle.

  8. High-Precision Computation and Mathematical Physics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2008-11-03

    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.

  9. High-precision laser machining of ceramics

    NASA Astrophysics Data System (ADS)

    Toenshoff, Hans K.; von Alvensleben, Ferdinand; Graumann, Christoph; Willmann, Guido

    1998-09-01

    The increasing demand for highly developed ceramic materials for various applications calls for innovative machining technologies yielding high accuracy and efficiency. Associated problems with conventional, i.e. mechanical methods, are unacceptable tool wear as well as force induced damages on ceramic components. Furthermore, the established grinding techniques often meet their limits if accurate complex 2D or 3D structures are required. In contrast to insufficient mechanical processes, UV-laser precision machining of ceramics offers not only a valuable technological alternative but a considerable economical aspect as well. In particular, excimer lasers provide a multitude of advantages for applications in high precision and micro technology. Within the UV wavelength range and pulses emitted in the nano-second region, minimal thermal effects on ceramics and polymers are observed. Thus, the ablation geometry can be controlled precisely in the lateral and vertical directions. In this paper, the excimer laser machining technology developed at the Laser Zentrum Hannover is explained. Representing current and future industrial applications, examinations concerning the precision cutting of alumina (Al2O3), and HF-composite materials, the ablation of ferrite ceramics for precision inductors and the structuring of SiC sealing and bearing rings are presented.

  10. High precision, rapid laser hole drilling

    DOEpatents

    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.

  11. High-Precision Photometry with the RCT

    NASA Astrophysics Data System (ADS)

    Everett, M.; Howell, S.; Davis, D.; McGruder, C. H., III; Gelderman, R.; Guinan, E.; Mattox, J. R.; Walter, D. K.

    2003-05-01

    We plan to conduct a high-precision photometric search for transitting extra-solar planets using the refurbished 1.3 m (50 inch) Robotically-Controlled Telescope (RCT) at Kitt Peak. The photometric capabilities and extra-solar planet search strategy for the RCT are discussed. Refurbishment of the RCT has been made possible by NASA grant NAG58762.

  12. High Precision Pressure Measurement with a Funnel

    ERIC Educational Resources Information Center

    Lopez-Arias, T.; Gratton, L. M.; Oss, S.

    2008-01-01

    A simple experimental device for high precision differential pressure measurements is presented. Its working mechanism recalls that of a hydraulic press, where pressure is supplied by insufflating air under a funnel. As an application, we measure air pressure inside a soap bubble. The soap bubble is inflated and connected to a funnel which is…

  13. High precision measurements in crustal dynamic studies

    NASA Technical Reports Server (NTRS)

    Wyatt, F.; Berger, J.

    1984-01-01

    The development of high-precision instrumentation for monitoring benchmark stability and evaluating coseismic strain and tilt signals is reviewed. Laser strainmeter and tilt observations are presented. Examples of coseismic deformation in several geographic locations are given. Evidence suggests that the Earth undergoes elastic response to abrupt faulting.

  14. High Precision Pressure Measurement with a Funnel

    ERIC Educational Resources Information Center

    Lopez-Arias, T.; Gratton, L. M.; Oss, S.

    2008-01-01

    A simple experimental device for high precision differential pressure measurements is presented. Its working mechanism recalls that of a hydraulic press, where pressure is supplied by insufflating air under a funnel. As an application, we measure air pressure inside a soap bubble. The soap bubble is inflated and connected to a funnel which is…

  15. High precision, rapid laser hole drilling

    DOEpatents

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

    2005-03-08

    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.

  16. High precision, rapid laser hole drilling

    DOEpatents

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

    2007-03-20

    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.

  17. High precision detector robot arm system

    DOEpatents

    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.

  18. [Laser-based radiometric calibration].

    PubMed

    Li, Zhi-gang; Zheng, Yu-quan

    2014-12-01

    Increasingly higher demands are put forward to spectral radiometric calibration accuracy and the development of new tunable laser based spectral radiometric calibration technology is promoted, along with the development of studies of terrestrial remote sensing, aeronautical and astronautical remote sensing, plasma physics, quantitative spectroscopy, etc. Internationally a number of national metrology scientific research institutes have built tunable laser based spectral radiometric calibration facilities in succession, which are traceable to cryogenic radiometers and have low uncertainties for spectral responsivity calibration and characterization of detectors and remote sensing instruments in the UK, the USA, Germany, etc. Among them, the facility for spectral irradiance and radiance responsivity calibrations using uniform sources (SIRCCUS) at the National Institute of Standards and Technology (NIST) in the USA and the Tunable Lasers in Photometry (TULIP) facility at the Physikalisch-Technische Bundesanstalt (PTB) in Germany have more representatives. Compared with lamp-monochromator systems, laser based spectral radiometric calibrations have many advantages, such as narrow spectral bandwidth, high wavelength accuracy, low calibration uncertainty and so on for radiometric calibration applications. In this paper, the development of laser-based spectral radiometric calibration and structures and performances of laser-based radiometric calibration facilities represented by the National Physical Laboratory (NPL) in the UK, NIST and PTB are presented, technical advantages of laser-based spectral radiometric calibration are analyzed, and applications of this technology are further discussed. Laser-based spectral radiometric calibration facilities can be widely used in important system-level radiometric calibration measurements with high accuracy, including radiance temperature, radiance and irradiance calibrations for space remote sensing instruments, and promote the

  19. High precision Woelter optic calibration facility

    SciTech Connect

    Morales, R.I.; Remington, B.A.; Schwinn, T. )

    1995-01-01

    We have developed an off-line facility for very precise characterization of the reflectance and spatial resolution of the grazing incidence Woelter type I x-ray optics used at Nova. The primary component of the facility is a new, very versatile, high brightness x-ray source consisting of a focused DC electron beam incident onto a precision manipulated target-pinhole array. The data are recorded with a selection of detectors. For imaging measurements we use direct exposure x-ray film modules or an x-ray charge-coupled device camera. For energy-resolved reflectance measurements, we use lithium drifted silicon detectors and a proportional counter. An [ital in] [ital situ] laser alignment system allows precise location and rapid periodic alignment verification of the x-ray point source, the statically mounted Woelter optic, and the chosen detector.

  20. High precision Woelter optic calibration facility

    SciTech Connect

    Morales, R.I.; Remington, B.A.; Schwinn, T.

    1994-05-02

    We have developed an off-line facility for very precise characterization of the reflectance and spatial resolution of the grazing incidence Woelter Type 1 x-ray optics used at Nova. The primary component of the facility is a high brightness, ``point`` x-ray source consisting of a focussed DC electron beam incident onto a precision manipulated target/pinhole array. The data are recorded with a selection of detectors. For imaging measurements we use direct exposure x-ray film modules or an x-ray CCD camera. For energy-resolved reflectance measurements, we use lithium drifted silicon detectors and a proportional counter. An in situ laser alignment system allows precise location and rapid periodic alignment verification of the x-ray point source, the statically mounted Woelter optic, and the chosen detector.

  1. The absolute radiometric calibration of the advanced very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    Slater, P. N.; Teillet, P. M.; Ding, Y.

    1988-01-01

    The need for independent, redundant absolute radiometric calibration methods is discussed with reference to the Thematic Mapper. Uncertainty requirements for absolute calibration of between 0.5 and 4 percent are defined based on the accuracy of reflectance retrievals at an agricultural site. It is shown that even very approximate atmospheric corrections can reduce the error in reflectance retrieval to 0.02 over the reflectance range 0 to 0.4.

  2. Radiometric Calibration Assessment of Commercial High Spatial Resolution Multispectral Image Products

    NASA Technical Reports Server (NTRS)

    Thome, Kurt; Leisso, Nathan; Buchanan, John

    2007-01-01

    This paper describes the results of commercial high spatial resolution sensors. The topics include: 1) Reflectance-based approach; 2) U of A test sites; 3) Test Site Selection; 4) Resort Living; 5) Aerosol parameters; 6) Surface reflectance retrieval; 7) Accuracy/precision; 8) Data sets; 9) June 23, 2005 for Ikonos; 10) QuickBird Results; 11) Ikonos results; 12) Orbview results; 13) Ikonos redux; and 14) Overall results.

  3. Broadband Radiometric LED Measurements

    PubMed Central

    Eppeldauer, G. P.; Cooksey, C. C.; Yoon, H. W.; Hanssen, L. M.; Podobedov, V. B.; Vest, R. E.; Arp, U.; Miller, C. C.

    2017-01-01

    At present, broadband radiometric measurements of LEDs with uniform and low-uncertainty results are not available. Currently, either complicated and expensive spectral radiometric measurements or broadband photometric LED measurements are used. The broadband photometric measurements are based on the CIE standardized V(λ) function, which cannot be used in the UV range and leads to large errors when blue or red LEDs are measured in its wings, where the realization is always poor. Reference irradiance meters with spectrally constant response and high-intensity LED irradiance sources were developed here to implement the previously suggested broadband radiometric LED measurement procedure [1, 2]. Using a detector with spectrally constant response, the broadband radiometric quantities of any LEDs or LED groups can be simply measured with low uncertainty without using any source standard. The spectral flatness of filtered-Si detectors and low-noise pyroelectric radiometers are compared. Examples are given for integrated irradiance measurement of UV and blue LED sources using the here introduced reference (standard) pyroelectric irradiance meters. For validation, the broadband measured integrated irradiance of several LED-365 sources were compared with the spectrally determined integrated irradiance derived from an FEL spectral irradiance lamp-standard. Integrated responsivity transfer from the reference irradiance meter to transfer standard and field UV irradiance meters is discussed. PMID:28649167

  4. Broadband radiometric LED measurements

    NASA Astrophysics Data System (ADS)

    Eppeldauer, G. P.; Cooksey, C. C.; Yoon, H. W.; Hanssen, L. M.; Podobedov, V. B.; Vest, R. E.; Arp, U.; Miller, C. C.

    2016-09-01

    At present, broadband radiometric LED measurements with uniform and low-uncertainty results are not available. Currently, either complicated and expensive spectral radiometric measurements or broadband photometric LED measurements are used. The broadband photometric measurements are based on the CIE standardized V(λ) function, which cannot be used in the UV range and leads to large errors when blue or red LEDs are measured in its wings, where the realization is always poor. Reference irradiance meters with spectrally constant response and high-intensity LED irradiance sources were developed here to implement the previously suggested broadband radiometric LED measurement procedure [1, 2]. Using a detector with spectrally constant response, the broadband radiometric quantities of any LEDs or LED groups can be simply measured with low uncertainty without using any source standard. The spectral flatness of filtered-Si detectors and low-noise pyroelectric radiometers are compared. Examples are given for integrated irradiance measurement of UV and blue LED sources using the here introduced reference (standard) pyroelectric irradiance meters. For validation, the broadband measured integrated irradiance of several LED-365 sources were compared with the spectrally determined integrated irradiance derived from an FEL spectral irradiance lamp-standard. Integrated responsivity transfer from the reference irradiance meter to transfer standard and field UV irradiance meters is discussed.

  5. Portable high precision pressure transducer system

    NASA Astrophysics Data System (ADS)

    Piper, T. C.; Morgan, J. P.; Marchant, N. J.; Bolton, S. M.

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank is presented. Since the response of the pressure transducer is temperature sensitive, it is continually housed in a battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on-board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display.

  6. Portable high precision pressure transducer system

    DOEpatents

    Piper, Thomas C.; Morgan, John P.; Marchant, Norman J.; Bolton, Steven M.

    1994-01-01

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum florescent display.

  7. Portable high precision pressure transducer system

    DOEpatents

    Piper, T.C.; Morgan, J.P.; Marchant, N.J.; Bolton, S.M.

    1994-04-26

    A high precision pressure transducer system is described for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display. 2 figures.

  8. Fiber Scrambling for High Precision Spectrographs

    NASA Astrophysics Data System (ADS)

    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. High precision tracking method for solar telescopes

    NASA Astrophysics Data System (ADS)

    Guo, Jingjing; Yang, Yunfei; Feng, Song; Ji, Kanfan; Lin, Jiaben; Zeng, Zhen; Wang, Bingxiang

    2016-07-01

    A high-precision real-time tracking method for solar telescopes was introduced in this paper based on the barycenter of full-disk solar images algorithm. To make sure the calculation was accurate and reliable, a series of strictly logic limits were set, such as setting gray threshold, judging the displacement of the barycenter and measuring the deviation from a perfect disk. A closed-loop control system was designed in the method. We located the barycenter of the full-disk images which recorded by large array CCD image sensor in real time and eliminate noise caused by bad weather, such as clouds and fog. The displacement of the barycenter was analyzed and transferred into control signal drove the motor to adjust the axis of telescope. An Ethernet interface was also provided for remote control. In the observation, the precision of this new method was better than 1″/30 minutes.

  10. High precision radial velocities with GIANO spectra

    NASA Astrophysics Data System (ADS)

    Carleo, I.; Sanna, N.; Gratton, R.; Benatti, S.; Bonavita, M.; Oliva, E.; Origlia, L.; Desidera, S.; Claudi, R.; Sissa, E.

    2016-06-01

    Radial velocities (RV) measured from near-infrared (NIR) spectra are a potentially excellent tool to search for extrasolar planets around cool or active stars. High resolution infrared (IR) spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. GIANO is an infrared echelle spectrograph at the Telescopio Nazionale Galileo (TNG) and it is a powerful tool to provide high resolution spectra for accurate RV measurements of exoplanets and for chemical and dynamical studies of stellar or extragalactic objects. No other high spectral resolution IR instrument has GIANO's capability to cover the entire NIR wavelength range (0.95-2.45 μm) in a single exposure. In this paper we describe the ensemble of procedures that we have developed to measure high precision RVs on GIANO spectra acquired during the Science Verification (SV) run, using the telluric lines as wavelength reference. We used the Cross Correlation Function (CCF) method to determine the velocity for both the star and the telluric lines. For this purpose, we constructed two suitable digital masks that include about 2000 stellar lines, and a similar number of telluric lines. The method is applied to various targets with different spectral type, from K2V to M8 stars. We reached different precisions mainly depending on the H-magnitudes: for H ˜ 5 we obtain an rms scatter of ˜ 10 m s-1, while for H ˜ 9 the standard deviation increases to ˜ 50 ÷ 80 m s-1. The corresponding theoretical error expectations are ˜ 4 m s-1 and 30 m s-1, respectively. Finally we provide the RVs measured with our procedure for the targets observed during GIANO Science Verification.

  11. Note: High precision measurements using high frequency gigahertz signals

    NASA Astrophysics Data System (ADS)

    Jin, Aohan; Fu, Siyuan; Sakurai, Atsunori; Liu, Liang; Edman, Fredrik; Pullerits, Tõnu; Öwall, Viktor; Karki, Khadga Jung

    2014-12-01

    Generalized lock-in amplifiers use digital cavities with Q-factors as high as 5 × 108 to measure signals with very high precision. In this Note, we show that generalized lock-in amplifiers can be used to analyze microwave (giga-hertz) signals with a precision of few tens of hertz. We propose that the physical changes in the medium of propagation can be measured precisely by the ultra-high precision measurement of the signal. We provide evidence to our proposition by verifying the Newton's law of cooling by measuring the effect of change in temperature on the phase and amplitude of the signals propagating through two calibrated cables. The technique could be used to precisely measure different physical properties of the propagation medium, for example, the change in length, resistance, etc. Real time implementation of the technique can open up new methodologies of in situ virtual metrology in material design.

  12. Note: High precision measurements using high frequency gigahertz signals.

    PubMed

    Jin, Aohan; Fu, Siyuan; Sakurai, Atsunori; Liu, Liang; Edman, Fredrik; Pullerits, Tõnu; Öwall, Viktor; Karki, Khadga Jung

    2014-12-01

    Generalized lock-in amplifiers use digital cavities with Q-factors as high as 5 × 10(8) to measure signals with very high precision. In this Note, we show that generalized lock-in amplifiers can be used to analyze microwave (giga-hertz) signals with a precision of few tens of hertz. We propose that the physical changes in the medium of propagation can be measured precisely by the ultra-high precision measurement of the signal. We provide evidence to our proposition by verifying the Newton's law of cooling by measuring the effect of change in temperature on the phase and amplitude of the signals propagating through two calibrated cables. The technique could be used to precisely measure different physical properties of the propagation medium, for example, the change in length, resistance, etc. Real time implementation of the technique can open up new methodologies of in situ virtual metrology in material design.

  13. Precision mass measurements of highly charged ions

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, A. A.; Bale, J. C.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Ettenauer, S.; Frekers, D.; Gallant, A. T.; Grossheim, A.; Lennarz, A.; Mane, E.; MacDonald, T. D.; Schultz, B. E.; Simon, M. C.; Simon, V. V.; Dilling, J.

    2012-10-01

    The reputation of Penning trap mass spectrometry for accuracy and precision was established with singly charged ions (SCI); however, the achievable precision and resolving power can be extended by using highly charged ions (HCI). The TITAN facility has demonstrated these enhancements for long-lived (T1/2>=50 ms) isobars and low-lying isomers, including ^71Ge^21+, ^74Rb^8+, ^78Rb^8+, and ^98Rb^15+. The Q-value of ^71Ge enters into the neutrino cross section, and the use of HCI reduced the resolving power required to distinguish the isobars from 3 x 10^5 to 20. The precision achieved in the measurement of ^74Rb^8+, a superallowed β-emitter and candidate to test the CVC hypothesis, rivaled earlier measurements with SCI in a fraction of the time. The 111.19(22) keV isomeric state in ^78Rb was resolved from the ground state. Mass measurements of neutron-rich Rb and Sr isotopes near A = 100 aid in determining the r-process pathway. Advanced ion manipulation techniques and recent results will be presented.

  14. High Precision Spectroscopy of Neutral Beryllium-9

    NASA Astrophysics Data System (ADS)

    Lau, Chui Yu; Williams, Will

    2015-05-01

    We report on the progress of high precision spectroscopy of the 2s2p singlet and triplet states in beryllium-9. Our goal is to improve the experimental precision on the energy levels of the 2s2p triplet J = 0, 1, and 2 states by a factor of 500, 100, and 500 respectively in order to delineate various theoretical predictions. The goal for the 2s2p singlet (J = 1) state is to improve the experimental precision on the energy level by a factor of 600 as a test of quantum electrodynamics. Our experimental setup consists of an oven capable of 1400 C that produces a collimated beam of neutral beryllium-9. The triplet states are probed with a 455 nm ECDL stabilized to a tellurium-210 line. The singlet state is probed with 235nm light from a frequency quadrupled titanium sapphire laser, where the frequency doubled light at 470 nm is stabilized to another tellurium-210 line. We also present our progress on improving the absolute accuracy of our frequency reference by using an ultrastable/low drift fiber coupled cavity.

  15. Imaging and radiometric performance simulation for a new high-performance dual-band airborne reconnaissance camera

    NASA Astrophysics Data System (ADS)

    Seong, Sehyun; Yu, Jinhee; Ryu, Dongok; Hong, Jinsuk; Yoon, Jee-Yeon; Kim, Sug-Whan; Lee, Jun-Ho; Shin, Myung-Jin

    2009-05-01

    In recent years, high performance visible and IR cameras have been used widely for tactical airborne reconnaissance. The process improvement for efficient discrimination and analysis of complex target information from active battlefields requires for simultaneous multi-band measurement from airborne platforms at various altitudes. We report a new dual band airborne camera designed for simultaneous registration of both visible and IR imagery from mid-altitude ranges. The camera design uses a common front end optical telescope of around 0.3m in entrance aperture and several relay optical sub-systems capable of delivering both high spatial resolution visible and IR images to the detectors. The camera design is benefited from the use of several optical channels packaged in a compact space and the associated freedom to choose between wide (~3 degrees) and narrow (~1 degree) field of view. In order to investigate both imaging and radiometric performances of the camera, we generated an array of target scenes with optical properties such as reflection, refraction, scattering, transmission and emission. We then combined the target scenes and the camera optical system into the integrated ray tracing simulation environment utilizing Monte Carlo computation technique. Taking realistic atmospheric radiative transfer characteristics into account, both imaging and radiometric performances were then investigated. The simulation results demonstrate successfully that the camera design satisfies NIIRS 7 detection criterion. The camera concept, details of performance simulation computation, the resulting performances are discussed together with future development plan.

  16. Precision timing measurements for high energy photons

    SciTech Connect

    Anderson, Dustin; Apreysan, Artur; Bornheim, Adi; Duarte, Javier; Newman, Harvey; Pena, Cristian; Ronzhin, Anatoly; Spiropulu, Maria; Trevor, Jason; Xie, Si; Zhu, Ren-Yuan

    2014-11-21

    Particle colliders operating at high luminosities present challenging environments for high energy physics event reconstruction and analysis. We discuss how timing information, with a precision on the order of 10 ps, can aid in the reconstruction of physics events under such conditions. We present calorimeter based timing measurements from test beam experiments in which we explore the ultimate timing precision achievable for high energy photons or electrons of 10 GeV and above. Using a prototype calorimeter consisting of a 1.7×1.7×1.7 cm3 lutetium–yttrium oxyortho-silicate (LYSO) crystal cube, read out by micro-channel plate photomultipliers, we demonstrate a time resolution of 33.5±2.1 ps for an incoming beam energy of 32 GeV. In a second measurement, using a 2.5×2.5×20 cm3 LYSO crystal placed perpendicularly to the electron beam, we achieve a time resolution of 59±11 ps using a beam energy of 4 GeV. We also present timing measurements made using a shashlik-style calorimeter cell made of LYSO and tungsten plates, and demonstrate that the apparatus achieves a time resolution of 54±5 ps for an incoming beam energy of 32 GeV.

  17. High precision laser photometer for laser optics

    NASA Astrophysics Data System (ADS)

    Zhao, Yuan'an; Hu, Guohang; Cao, Zhen; Liu, Shijie; Zhu, Meiping; Shao, Jianda

    2017-06-01

    Development of laser systems requires optical components with high performance, and a high-precision double-beam laser photometer was designed and established to measure the optical performance at 1064nm. Double beam design and lock-in technique was applied to decrease the impact of light energy instability and electric noise. Pairs of samples were placed symmetrically to eliminate beam displacement, and laser scattering imaging technique was applied to determine the influence of surface defect on the optical performance. Based on the above techniques, transmittance and reflection of pairs of optics were obtained, and the measurement precision was improved to 0.06%. Different types of optical loss, such as total loss, volume loss, residual reflection and surface scattering loss, were obtained from the transmittance and reflection measurement of samples with different thickness. Comparison of optical performance of the test points with and without surface defects, the influence of surface defects on optical performance was determined. The optical performance of Nd-glass at 1064nm were measured as an example. Different types of optical loss and the influence of surface defects on the optical loss was determined.

  18. Research about the high precision temperature measurement

    NASA Astrophysics Data System (ADS)

    Lin, J.; Yu, J.; Zhu, X.; Zeng, Z.; Deng, Y.

    2012-12-01

    High precision temperature control system is one of most important support conditions for tunable birefringent filter.As the first step,we researched some high precision temperature measurement methods for it. Firstly, circuits with a 24 bit ADC as the sensor's reader were carefully designed; Secondly, an ARM porcessor is used as the centrol processing unit, it provides sufficient reading and procesing ability; Thirdly, three kinds of sensors, PT100, Dale 01T1002-5 thermistor, Wheatstone bridge(constructed by pure copper and manganin) as the senor of the temperature were tested respectively. The resolution of the measurement with these three kinds of sensors are all better than 0.001 that's enough for 0.01 stability temperature control. Comparatively, Dale 01T1002-5 thermistor could get the most accurate temperature of the key point, Wheatstone bridge could get the most accurate mean temperature of the whole layer, both of them will be used in our futrue temperature controll system.

  19. High precision innovative micropump for artificial pancreas

    NASA Astrophysics Data System (ADS)

    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.

  20. High Precision Rovibrational Spectroscopy of OH+

    NASA Astrophysics Data System (ADS)

    Markus, Charles R.; Hodges, James N.; Perry, Adam J.; Kocheril, G. Stephen; Müller, Holger S. P.; McCall, Benjamin J.

    2016-02-01

    The molecular ion OH+ 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+. The ions were produced in a water cooled discharge of O2, H2, 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 3Σ- linear molecule effective Hamiltonian to determine improved spectroscopic parameters which were used to predict the pure rotational transition frequencies.

  1. Highly damped kinematic coupling for precision instruments

    DOEpatents

    Hale, Layton C.; Jensen, Steven A.

    2001-01-01

    A highly damped kinematic coupling for precision instruments. The kinematic coupling provides support while causing essentially no influence to its nature shape, with such influences coming, for example, from manufacturing tolerances, temperature changes, or ground motion. The coupling uses three ball-cone constraints, each combined with a released flexural degree of freedom. This arrangement enables a gain of higher load capacity and stiffness, but can also significantly reduce the friction level in proportion to the ball radius divided by the distance between the ball and the hinge axis. The blade flexures reduces somewhat the stiffness of the coupling and provides an ideal location to apply constrained-layer damping which is accomplished by attaching a viscoelastic layer and a constraining layer on opposite sides of each of the blade flexures. The three identical ball-cone flexures provide a damped coupling mechanism to kinematically support the projection optics system of the extreme ultraviolet lithography (EUVL) system, or other load-sensitive apparatus.

  2. High Precision Isotopic Reference Material Program

    NASA Astrophysics Data System (ADS)

    Mann, J. L.; Vocke, R. D.

    2007-12-01

    Recent developments in thermal ionization and inductively coupled plasma multicollector mass spectrometers have lead to "high precision" isotope ratio measurements with uncertainties approaching a few parts in 106. These new measurement capabilities have revolutionized the study of isotopic variations in nature by increasing the number of elements showing natural variations by almost a factor of two, and new research areas are actively opening up in climate change, health, ecology, geology and forensic studies. Because the isotopic applications are impacting very diverse fields, there is at present little effective coordination between research laboratories over reference materials and the values to apply to those materials. NIST had originally developed the techniques for producing accurate isotopic characterizations, culminating in the NIST Isotopic SRM series. The values on existing materials however are insufficiently precise and, in some cases, may be isotopically heterogeneous. A new generation of isotopic standards is urgently needed and will directly affect the quality and scope of emergent applications and ensure that the results being derived from these diverse fields are comparable. A series of new isotopic reference materials similar to the NIST 3100 single element solution series is being designed for this purpose and twelve elements have been selected as having the most pressing need. In conjunction with other expert users and National Metrology Institutes, an isotopic characterization of the respective 12 selected ampoules from the NIST single element solution series is currently underway. In this presentation the preliminary results of this screening will be discussed as well as the suitability of these materials in terms of homogeneity and purity, long term stability and availability, and isotopic relevance. Approaches to value assignment will also be discussed.

  3. Aerodynamic window for high precision laser drilling

    NASA Astrophysics Data System (ADS)

    Sommer, Steffen; Dausinger, Friedrich; Berger, Peter; Hügel, Helmuth

    2007-05-01

    High precision laser drilling is getting more and more interesting for industry. Main applications for such holes are vaporising and injection nozzles. To enhance quality, the energy deposition has to be accurately defined by reducing the pulse duration and thereby reducing the amount of disturbing melting layer. In addition, an appropriate processing technology, for example the helical drilling, yields holes in steel at 1 mm thickness and diameters about 100 μm with correct roundness and thin recast layers. However, the processing times are still not short enough for industrial use. Experiments have shown that the reduction of the atmospheric pressure down to 100 hPa enhances the achievable quality and efficiency, but the use of vacuum chambers in industrial processes is normally quite slow and thus expensive. The possibility of a very fast evacuation is given by the use of an aerodynamic window, which produces the pressure reduction by virtue of its fluid dynamic features. This element, based on a potential vortex, was developed and patented as out-coupling window for high power CO II lasers by IFSW 1, 2, 3. It has excellent tightness and transmission properties, and a beam deflection is not detectable. The working medium is compressed air, only. For the use as vacuum element for laser drilling, several geometrical modifications had to be realized. The prototype is small enough to be integrated in a micromachining station and has a low gas flow. During the laser pulse, which is focussed through the potential flow, a very high fluence is reached, but the measurements have not shown any beam deflection or focal shifting. The evacuation time is below 300 ms so that material treatment with changing ambient pressure is possible, too. Experimental results have proven the positive effect of the reduced ambient pressure on the drilling process for the regime of nano- and picosecond laser pulses. Plasma effects are reduced and, because of the less absorption, the

  4. High precision optical surface metrology using deflectometry

    NASA Astrophysics Data System (ADS)

    Huang, Run

    Software Configurable Optical Test System (SCOTS) developed at University of Arizona is a highly efficient optical metrology technique based on the principle of deflectometry, which can achieve comparable accuracy with interferometry but with low-cost hardware. In a SCOTS test, an LCD display is used to generate structured light pattern to illuminate the test optics and the reflected light is captured by a digital camera. The surface slope of test optics is determined by triangulation of the display pixels, test optics, and the camera. The surface shape is obtained by the integration of the slopes. Comparing to interferometry, which has long served as an accurate non-contact optical metrology technology, SCOTS overcomes the limitation of dynamic range and sensitivity to environment. It is able to achieve high dynamic range slope measurement without requiring null optics. In this dissertation, the sensitivity and performance of the test system have been analyzed comprehensively. Sophisticated calibrations of system components have been investigated and implemented in different metrology projects to push this technology to a higher accuracy including low-order terms. A compact on-axis SCOTS system lowered the testing geometry sensitivity in the metrology of 1-meter highly aspheric secondary mirror of Large Binocular Telescope. Sub-nm accuracy was achieved in testing a high precision elliptical X-ray mirror by using reference calibration. A well-calibrated SCOTS was successfully constructed and is, at the time of writing this dissertation, being used to provide surface metrology feedback for the fabrication of the primary mirror of Daniel K. Inouye Solar Telescope which is a 4-meter off-axis parabola with more than 8 mm aspherical departure.

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

    NASA Astrophysics Data System (ADS)

    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.

  6. Radiometric inter-sensor cross-calibration uncertainty using a traceable high accuracy reference hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Gorroño, Javier; Banks, Andrew C.; Fox, Nigel P.; Underwood, Craig

    2017-08-01

    Optical earth observation (EO) satellite sensors generally suffer from drifts and biases relative to their pre-launch calibration, caused by launch and/or time in the space environment. This places a severe limitation on the fundamental reliability and accuracy that can be assigned to satellite derived information, and is particularly critical for long time base studies for climate change and enabling interoperability and Analysis Ready Data. The proposed TRUTHS (Traceable Radiometry Underpinning Terrestrial and Helio-Studies) mission is explicitly designed to address this issue through re-calibrating itself directly to a primary standard of the international system of units (SI) in-orbit and then through the extension of this SI-traceability to other sensors through in-flight cross-calibration using a selection of Committee on Earth Observation Satellites (CEOS) recommended test sites. Where the characteristics of the sensor under test allows, this will result in a significant improvement in accuracy. This paper describes a set of tools, algorithms and methodologies that have been developed and used in order to estimate the radiometric uncertainty achievable for an indicative target sensor through in-flight cross-calibration using a well-calibrated hyperspectral SI-traceable reference sensor with observational characteristics such as TRUTHS. In this study, Multi-Spectral Imager (MSI) of Sentinel-2 and Landsat-8 Operational Land Imager (OLI) is evaluated as an example, however the analysis is readily translatable to larger-footprint sensors such as Sentinel-3 Ocean and Land Colour Instrument (OLCI) and Visible Infrared Imaging Radiometer Suite (VIIRS). This study considers the criticality of the instrumental and observational characteristics on pixel level reflectance factors, within a defined spatial region of interest (ROI) within the target site. It quantifies the main uncertainty contributors in the spectral, spatial, and temporal domains. The resultant tool

  7. JACIE Radiometric Assessment of QuickBird Multispectral Imagery

    NASA Technical Reports Server (NTRS)

    Pagnutti, Mary; Carver, David; Holekamp, Kara; Knowlton, Kelly; Ryan, Robert; Zanoni, Vicki; Thome, Kurtis; Aaron, David

    2004-01-01

    Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities can place confidence in the imagery they use and can fully understand its properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, the NASA Stennis Space Center (SSC) Earth Science Applications (ESA) directorate,through the Joint Agency for Commercial Imagery Evaluation (JACIE) framework, established a commercial imaging satellite radiometric calibration team consisting of two groups: 1) NASA SSC ESA, supported by South Dakota State University, and 2) the University of Arizona Remote Sensing Group. The two groups determined the absolute radiometric calibration coefficients of the Digital Globe 4-band, 2.4-m QuickBird multispectral product covering the visible through near-infrared spectral region. For a 2-year period beginning in 2002, both groups employed some variant of a reflectance-based vicarious calibration approach, which required ground-based measurements coincident with QuickBird image acquisitions and radiative transfer calculations. The groups chose several study sites throughout the United States that covered nearly the entire dynamic range of the QuickBird sensor. QuickBird at-sensor radiance values were compared with those estimated by the two independent groups to determine the QuickBird sensor's radiometric accuracy. Approximately 20 at-sensor radiance estimates were vicariously determined each year. The estimates were combined to provide a high-precision radiometric gain calibration coefficient. The results of this evaluation provide the user community with an independent assessment of the QuickBird sensor's absolute calibration and stability over the 2-year period. While the techniques and method described reflect those developed at the NASA SSC, the results of both JACIE team groups are

  8. High precision flux measurements with ENUBET

    NASA Astrophysics Data System (ADS)

    Pozzato, M.; ENUBET collaboration

    2017-09-01

    The challenges of precision neutrino physics (i.e the study of CP violation) require measurements of absolute ν cross sections at the GeV scale with exquisite (O(1)%) precision. Such precision is presently limited to about 10% by the uncertainties on neutrino flux at the source. A reduction of this uncertainty by one order of magnitude can be achieved monitoring the positron production in the decay tunnel originating from the Ke3 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 (νe and {\\displaystyle \\bar{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 (PI A. Longhin), recently approved by the European Research Council (grant agreement N° 681647). In this poster, we will present the Project and the early experimental results on ultra-compact calorimeters that can embedded in the instrumented decay tunnel.

  9. High precision attitude determination for Magsat

    NASA Astrophysics Data System (ADS)

    Abshire, G.; McCutcheon, R.; Summers, G.; Vanlandingham, F.; Meyers, G.

    1981-08-01

    A two phase approach to attitude determination software development is introduced. The prelaunch planning and software activities connected with the development and testing of the baseline system for processing nominal attitude data for MAGSAT are described and postlaunch analysis and modifications are outlined. Attitude data processing began 5 months after launch so that postlaunch anomalies could be accounted for. Another advantage of the two phase approach is that costs are reduced because the system is not burdened with software dealing with all possible contingencies. A definitive, continuous, time history of the three axis attitude of the spacecraft was generated to a precision of 20 arc sec (one standard deviation), in each axis. Sensor alignment determinations were done continuously because of the deletrious effects of changing alignments on attitude precision.

  10. High-precision triangular-waveform generator

    DOEpatents

    Mueller, T.R.

    1981-11-14

    An ultra-linear ramp generator having separately programmable ascending and decending ramp rates and voltages is provided. Two constant current sources provide the ramp through an integrator. Switching of the current at current source inputs rather than at the integrator input eliminates switching transients and contributes to the waveform precision. The triangular waveforms produced by the waveform generator are characterized by accurate reproduction and low drift over periods of several hours. The ascending and descending slopes are independently selectable.

  11. High-precision positioning of radar scatterers

    NASA Astrophysics Data System (ADS)

    Dheenathayalan, Prabu; Small, David; Schubert, Adrian; Hanssen, Ramon F.

    2016-05-01

    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 of synthetic aperture radar (SAR) scatterers in a 2D radar coordinate system, after compensating for atmosphere and tidal effects, is in the order of centimeters for TerraSAR-X (TSX) spotlight images. However, the absolute positioning in 3D and its quality description are not well known. Here, we exploit time-series interferometric SAR to enhance the positioning capability in three dimensions. The 3D positioning precision is parameterized by a variance-covariance matrix and visualized as an error ellipsoid centered at the estimated position. The intersection of the error ellipsoid with objects in the field is exploited to link radar scatterers to real-world objects. We demonstrate the estimation of scatterer position and its quality using 20 months of TSX stripmap acquisitions over Delft, the Netherlands. Using trihedral corner reflectors (CR) for validation, the accuracy of absolute positioning in 2D is about 7 cm. In 3D, an absolute accuracy of up to ˜ 66 cm is realized, with a cigar-shaped error ellipsoid having centimeter precision in azimuth and range dimensions, and elongated in cross-range dimension with a precision in the order of meters (the ratio of the ellipsoid axis lengths is 1/3/213, respectively). The CR absolute 3D position, along with the associated error ellipsoid, is found to be accurate and agree with the ground truth position at a 99 % confidence level. For other non-CR coherent scatterers, the error ellipsoid concept is validated using 3D building models. In both cases, the error ellipsoid not only serves as a quality descriptor, but can also help to associate radar scatterers to real-world objects.

  12. Evaluation of the Applicability of Solar and Lamp Radiometric Calibrations of a Precision Sun Photometer Operating Between 300 and 1025 nm

    NASA Technical Reports Server (NTRS)

    Schmid, Beat; Spyak, Paul R.; Biggar, Stuart F.; Joerg, Sekler; Ingold, Thomas; Maetzler, Christian; Kaempfer, Niklaus

    2000-01-01

    Over a period of 3 year a precision Sun photometer (SPM) operating between 300 and 1025 nm was calibrated four times at three different high-mountain sites in Switzerland, Germany, and the United States by means of the Langley-plot technique. We found that for atmospheric window wavelengths the total error (2 sigma-statistical plus systematic errors) of the calibration constants V(sub 0)(lambda), the SPM voltage in the absence of any attenuating atmosphere, can be kept below 1.60% in the UV-A and blue, 0.9% in the mid-visible, and 0.6% in the near-infra red spectral region. For SPM channels within strong water-vapor or ozone absorption bands a modified Langley-plot technique was used to determine V(sub 0)(lambda) with a lower accuracy. Within the same period of time, we calibrated the SPM five times using irradiance standard lamps in the optical labs of the Physikalisch-Meteorologisches Observatorium Davos and World Radiation Center, Switzerland, and of the Remote Sensing Group of the Optical Sciences Center, University of Arizona, Tucson, Arizona. The lab calibration method requires knowledge of the extraterrestrial spectral irradiance. When we refer the standard lamp results to the World Radiation Center extraterrestrial solar irradiance spectrum, they agree with the Langley results within 2% at 6 or 13 SPM wavelengths. The largest disagreement (4.4%) is found for the channel centered at 610 nm. The results of these intercomparisons change significantly when the lamp results are referred to two different extraterrestrial solar irradiance spectra that have become recently available.

  13. An Enhanced Algorithm for Automatic Radiometric Harmonization of High-Resolution Optical Satellite Imagery Using Pseudoinvariant Features and Linear Regression

    NASA Astrophysics Data System (ADS)

    Langheinrich, M.; Fischer, P.; Probeck, M.; Ramminger, G.; Wagner, T.; Krauß, T.

    2017-05-01

    The growing number of available optical remote sensing data providing large spatial and temporal coverage enables the coherent and gapless observation of the earth's surface on the scale of whole countries or continents. To produce datasets of that size, individual satellite scenes have to be stitched together forming so-called mosaics. Here the problem arises that the different images feature varying radiometric properties depending on the momentary acquisition conditions. The interpretation of optical remote sensing data is to a great extent based on the analysis of the spectral composition of an observed surface reflection. Therefore the normalization of all images included in a large image mosaic is necessary to ensure consistent results concerning the application of procedures to the whole dataset. In this work an algorithm is described which enables the automated spectral harmonization of satellite images to a reference scene. As the stable and satisfying functionality of the proposed algorithm was already put to operational use to process a high number of SPOT-4/-5, IRS LISS-III and Landsat-5 scenes in the frame of the European Environment Agency's Copernicus/GMES Initial Operations (GIO) High-Resolution Layer (HRL) mapping of the HRL Forest for 20 Western, Central and (South)Eastern European countries, it is further evaluated on its reliability concerning the application to newer Sentinel-2 multispectral imaging products. The results show that the algorithm is comparably efficient for the processing of satellite image data from sources other than the sensor configurations it was originally designed for.

  14. Combined high-resolution aeromagnetic and radiometric mapping of uranium mineralization and tectonic settings in Northeastern Nigeria

    NASA Astrophysics Data System (ADS)

    Adepelumi, A. A.; Falade, A. H.

    2017-09-01

    Geological lineaments, depths to the basement, uranium concentrations, and remobilization in parts of the Upper Benue Trough, covering about 55 × 55 km2 (longitudes 11°30'-12°00'E and 10°30'-10°30'N), Northeastern Nigeria were investigated using integrated High-Resolution Aeromagnetic Data (HRAD) and radiometric data. This was with a view to identifying the potential zones of uranium occurrence in the area. The HRAD was processed to accentuate anomalies of interest and depths estimate of 150-1941 m were obtained from source parameter imaging technique. The results from the superposition of the horizontal gradient magnitude, analytical signal amplitude, first vertical derivative, and 3D Euler solutions of the HRAD revealed that the study area was dissected by linear structures that trend ENE-WSW, NE-SW, E-W, NNE-SSW, WNW-ESE, and NW-SE; among which the ENE-WSW and NE-SW trends dominated. Analyses of radiometric data showed that uranium ores in the study area were possibly remobilized epigenetically from the granitic rocks, and were later deposited into sedimentary rocks (Bima formation). Burashika group (Bongna hills) and Wawa area of the study area showed vein-type deposits, while the anatectic migmatite in the northeastern region and the uranium rich Bima formation showed both fault/fracture and contact types of deposition. It was also observed the northwesterly and southeasterly, dominant dip direction, dipping faults dip in the same direction as the paleocurrent direction (direction of depositions of sediments), and trend in a direction perpendicular to the hypothetical direction of uranium deposition. The study concluded that the studied area is dissected by several linear structures and the studied area possibly contains deposits of uranium ore, which are likely to be found in: the Bima Sandstones of Wade, Shinga, Bima hill, Wuyo, Teli, Bryel, Dali, Barkan, Gasi, Kunkun, Boragara, Deba, and Gberundi localities; the anatectic migmatite at Kubuku, Whada

  15. NASA Radiometric Characterization

    NASA Technical Reports Server (NTRS)

    Holekamp, Kara

    2006-01-01

    This viewgraph presentation reviews the characterization of radiometric data by NASA. The objective was to perform radiometric vicarious calibrations of imagery and compare with vendor-provided calibration coefficients. The approach was to use multiple, well-characterized sites. These sites are widely used by the NASA science community for radiometric characterization of airborne and space borne sensors. Using the data from these sites, the investigators performed independent characterizations with independent teams. Each team has slightly different measurement techniques and data processing methods.

  16. Ultra-high precision white dwarf asteroseismology

    NASA Astrophysics Data System (ADS)

    Giammichele, Noemi; Charpinet, Stéphane; Fontaine, Gilles; Brassard, Pierre; Zong, Weikai

    We present a brief progress report in our quest for deriving seismic models of pulsating white dwarfs that can account simultaneously for all the observed periods at the precision of the observations. We point out that this is possible from a pratical point of view only if parametrized models are used to complement evolutionary models. We adopt a double optimization procedure that insures that the best possible model in parameter space is found objectively and automatically. Our ultimate goal is to be able to account for the exquisite period data gathered with Kepler and Kepler-2 on key pulsating white dwarfs of both the DA (ZZ Ceti) and DB (V777 Her) type.

  17. Vertical high-precision Michelson wavemeter

    NASA Astrophysics Data System (ADS)

    Morales, A.; de Urquijo, J.; Mendoza, A.

    1993-01-01

    We have designed and tested a traveling, Michelson-type vertical wavemeter for the wavelength measurement of tunable continuous-wave lasers in the visible part of the spectrum. The interferometer has two movable corner cubes, suspending vertically from a driving setup resembling Atwood's machine. To reduce the fraction-of-fringe error, a vernier-type coincidence circuit was used. Although simple, this wavemeter has a relative precision of 3.2 parts in 109 for an overall fringe count of about 7×106.

  18. NASA IKONOS Radiometric Characterization

    NASA Technical Reports Server (NTRS)

    Pagnutti, Mary; Frisbee, Troy; Zanoni, Vicki; Blonski, Slawek; Daehler, Erik; Grant, Brennan; Holekamp, Kara; Ryan, Robert; Sellers, Richard; Smith, Charles

    2002-01-01

    The objective of this program: Perform radiometric vicarious calibrations of IKQNOS imagery and compare with Space Imaging calibration coefficients The approach taken: utilize multiple well-characterized sites which are widely used by the NASA science community for radiometric characterization of airborne and spaceborne sensors; and to Perform independent characterizations with independent teams. Each team has slightly different measurement techniques and data processing methods.

  19. Geometric/radiometric calibration from ordinary images for high resolution satellite systems

    NASA Astrophysics Data System (ADS)

    Latry, Christophe

    2011-10-01

    This paper presents two techniques respectively devoted to noise and geometric characteristics assessment from standard images instead of dedicated ones. The noise computation technique assumes that high spatial frequencies are sufficiently weakened by MTF so that only noise remains near Nyquist frequency. It uses Fourier Transform or wavelet packet decomposition. The second technique is based upon matching processing between spectral bands assuming the imaging system focal plane has staggered arrays. It yields very accurate information on focal plane layout as well as high frequency attitude disturbances. Results obtained on simulated images as well as Worldview-2 real products are detailed

  20. Relative radiometric calibration of LANDSAT TM reflective bands

    NASA Technical Reports Server (NTRS)

    Barker, J. L.

    1984-01-01

    A common scientific methodology and terminology is outlined for characterizing the radiometry of both TM sensors. The magnitude of the most significant sources of radiometric variability are discussed and methods are recommended for achieving the exceptional potential inherent in the radiometric precision and accuracy of the TM sensors.

  1. High resolution radiometric measurements of convective storms during the GATE experiment

    NASA Technical Reports Server (NTRS)

    Fowler, G.; Lisa, A. S.

    1976-01-01

    Using passive microwave data from the NASA CV-990 aircraft and radar data collected during the Global Atmospheric Research Program Atlantic Tropical Experiment (GATE), an empirical model was developed relating brightness temperatures sensed at 19.35 GHz to surface rainfall rates. This model agreed well with theoretical computations of the relationship between microwave radiation and precipitation in the tropics. The GATE aircraft microwave data was then used to determine the detailed structure of convective systems. The high spatial resolution of the data permitted identification of individual cells which retained unique identities throughout their lifetimes in larger cloud masses and allowed analysis of the effects of cloud merger.

  2. High-spectral-resolution radiometric measurements of aerosol extinction over an urban region in India

    NASA Astrophysics Data System (ADS)

    Devara, P. C. S.; Ramkumar, M.; Maheskumar, R. S.; Pandithurai, G.

    2001-06-01

    Concurrent observations of aerosol optical depth (AOD) were carried out using a high-spectral-resolution radiometer (HSRR) and solar radiometer (SR) at the Indian Institute of Tropical Meteorology (IITM), Pune, India, on all clear-sky days available during November 1995-February 1996. The HSRR observations were collected at 5 nm intervals throughout the 400-700 nm spectrum while the SR measurements were made at discrete wavelengths of 400, 600, 940, 1060 and 1630 nm. In order to study the effect of integrated spectral observations on the derived AODs as compared to such depths from a single spectrum, multi-spectral observations at 2 nm intervals were collected. The AODs and their wavelength dependence from the HSRR and SR are compared and fairly good agreement found. The HSRR derived AODs at 400 nm and 700 nm from the present data sets are compared with those obtained during the winters of 1993-94 and 1994-95. The results reveal greater AODs, indicating abundance of aerosol particle concentration, during 1995-96 as compared to 1993-94 and 1994-95.

  3. Precision Timing Calorimeter for High Energy Physics

    DOE PAGES

    Anderson, Dustin; Apresyan, Artur; Bornheim, Adolf; ...

    2016-04-01

    Here, we present studies on the performance and characterization of the time resolution of LYSO-based calorimeters. Results for an LYSO sampling calorimeter and an LYSO-tungsten Shashlik calorimeter are presented. We also demonstrate that a time resolution of 30 ps is achievable for the LYSO sampling calorimeter. Timing calorimetry is described as a tool for mitigating the effects due to the large number of simultaneous interactions in the high luminosity environment foreseen for the Large Hadron Collider.

  4. High-precision gauging of metal rings

    NASA Astrophysics Data System (ADS)

    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.

  5. High precision mass measurements for wine metabolomics

    PubMed Central

    Roullier-Gall, Chloé; Witting, Michael; Gougeon, Régis D.; Schmitt-Kopplin, Philippe

    2014-01-01

    An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS2. In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy. PMID:25431760

  6. High precision mass measurements for wine metabolomics

    NASA Astrophysics Data System (ADS)

    Roullier-Gall, Chloé; Witting, Michael; Gougeon, Régis; Schmitt-Kopplin, Philippe

    2014-11-01

    An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS². In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy.

  7. Precision probes of QCD at high energies

    NASA Astrophysics Data System (ADS)

    Alioli, Simone; Farina, Marco; Pappadopulo, Duccio; Ruderman, Joshua T.

    2017-07-01

    New physics, that is too heavy to be produced directly, can leave measurable imprints on the tails of kinematic distributions at the LHC. We use energetic QCD processes to perform novel measurements of the Standard Model (SM) Effective Field Theory. We show that the dijet invariant mass spectrum, and the inclusive jet transverse momentum spectrum, are sensitive to a dimension 6 operator that modifies the gluon propagator at high energies. The dominant effect is constructive or destructive interference with SM jet production. We compare differential next-to-leading order predictions from POWHEG to public 7 TeV jet data, including scale, PDF, and experimental uncertainties and their respective correlations. We constrain a New Physics (NP) scale of 3.5 TeV with current data. We project the reach of future 13 and 100 TeV measurements, which we estimate to be sensitive to NP scales of 8 and 60 TeV, respectively. As an application, we apply our bounds to constrain heavy vector octet colorons that couple to the QCD current. We project that effective operators will surpass bump hunts, in terms of coloron mass reach, even for sequential couplings.

  8. Precision probes of QCD at high energies

    DOE PAGES

    Alioli, Simone; Farina, Marco; Pappadopulo, Duccio; ...

    2017-07-20

    New physics, that is too heavy to be produced directly, can leave measurable imprints on the tails of kinematic distributions at the LHC.We use energetic QCD processes to perform novel measurements of the Standard Model (SM) Effective Field Theory. We show that the dijet invariant mass spectrum, and the inclusive jet transverse momentum spectrum, are sensitive to a dimension 6 operator that modifies the gluon propagator at high energies. The dominant effect is constructive or destructive interference with SM jet production. Here, we compare differential next-to-leading order predictions from POWHEG to public 7TeV jet data, including scale, PDF, and experimentalmore » uncertainties and their respective correlations. Furthermore, we constrain a New Physics (NP) scale of 3.5TeV with current data. We project the reach of future 13 and 100TeV measurements, which we estimate to be sensitive to NP scales of 8 and 60TeV, respectively. As an application, we apply our bounds to constrain heavy vector octet colorons that couple to the QCD current. We conclude that effective operators will surpass bump hunts, in terms of coloron mass reach, even for sequential couplings.« less

  9. Precision timing calorimeter for high energy physics

    NASA Astrophysics Data System (ADS)

    Anderson, Dustin; Apresyan, Artur; Bornheim, Adolf; Duarte, Javier; Peña, Cristián; Spiropulu, Maria; Trevor, Jason; Xie, Si; Ronzhin, Anatoly

    2016-07-01

    Scintillator based calorimeter technology is studied with the aim to achieve particle detection with a time resolution on the order of a few 10 ps for photons and electrons at energies of a few GeV and above. We present results from a prototype of a 1.4×1.4×11.4 cm3 sampling calorimeter cell consisting of tungsten absorber plates and Cerium-doped Lutetium Yttrium Orthosilicate (LYSO) crystal scintillator plates. The LYSO plates are read out with wave lengths shifting fibers which are optically coupled to fast photo detectors on both ends of the fibers. The measurements with electrons were performed at the Fermilab Test Beam Facility (FTBF) and the CERN SPS H2 test beam. In addition to the baseline setup plastic scintillation counter and a MCP-PMT were used as trigger and as a reference for a time of flight measurement (TOF). We also present measurements with a fast laser to further characterize the response of the prototype and the photo sensors. All data were recorded using a DRS4 fast sampling digitizer. These measurements are part of an R&D program whose aim is to demonstrate the feasibility of building a large scale electromagnetic calorimeter with a time resolution on the order of 10 ps, to be used in high energy physics experiments.

  10. Computer-Aided High Precision Verification Of Miniature Spring Structure

    NASA Astrophysics Data System (ADS)

    Bow, Sing T.; Wang, Da-hao; Chen, Tsung-sheng; Newell, Darrell E.

    1990-01-01

    A system is proposed for the high precision on-line verification of the minia-ture spring structure, including overall height, diameters of various coils as well as pitches between neighboring coils of the miniature conical springs. High preci-sion measurements without physical contact and short processing time are achieved. Deformations of any kind on the conical springs can be identified even from the worst viewing direction.

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

    DOEpatents

    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).

  12. Galvanometer deflection: a precision high-speed system.

    PubMed

    Jablonowski, D P; Raamot, J

    1976-06-01

    An X-Y galvanometer deflection system capable of high precision in a random access mode of operation is described. Beam positional information in digitized form is obtained by employing a Ronchi grating with a sophisticated optical detection scheme. This information is used in a control interface to locate the beam to the required precision. The system is characterized by high accuracy at maximum speed and is designed for operation in a variable environment, with particular attention placed on thermal insensitivity.

  13. Improved capabilities of the Chinese high-resolution remote sensing satellite GF-1 for monitoring suspended particulate matter (SPM) in inland waters: Radiometric and spatial considerations

    NASA Astrophysics Data System (ADS)

    Li, Jian; Chen, Xiaoling; Tian, Liqiao; Huang, Jue; Feng, Lian

    2015-08-01

    Dominated by high dynamic and small-scale variability, remote sensing of inland or coastal waters is frequently impended by insufficient spatial resolutions from conventional ocean color sensors. With the urgent need and the rapid progress in high-resolution earth observation systems (HR), it is critical to assess the capabilities of HR in inland water monitoring. In this study, the radiometric and spatial performance of the Chinese high-resolution GF-1 Wide Field Imager (WFI) data for water quality monitoring were evaluated in term of the signal-to-noise ratio (SNR), sensitivity to suspended particulate matter (SPM) variations and spatial depiction ability. The SNR was statistically estimated from variable moving window method, and the radiometric sensitivity was simulated using the Moderate Resolution Atmospheric Transmission (MODTRAN) under varied surface and atmospheric conditions. Results indicated that both the SNR and the radiometric sensitivity of the GF-1 WFI were enhanced by 3-5 times than its predecessor (Chinese HJ-1 CCD) or Landsat 7 Enhanced Thematic Mapper Plus (ETM+), and were comparable to Landsat 8 Operational Land Imager (OLI) and Moderate Resolution Imaging Spectroradiometer (MODIS) medium-resolution bands (250 and 500 m), which have been extensively applied in inland water environment monitoring. Cross comparisons demonstrated high consistency of the spatial distribution and concentration of SPM maps between GF-1 WFI and Landsat 8 OLI. Furthermore, more than 75% of the spatial variations in high turbid waters were resolved from GF-1 WFI data, whereas the ability dropped to 40% when the spatial resolution was degraded to 250 m (MODIS-like sensors). Overall, GF-1 WFI is extraordinarily promising with an enhanced SNR, an increased spectral sensitivity to SPM variations and an advanced spatial resolution. With the ongoing plans of the successive GF series (2-7), the findings would serve as a reference for forthcoming applications, and are critical

  14. High-precision camera distortion measurements with a ``calibration harp''

    NASA Astrophysics Data System (ADS)

    Tang, Zhongwei; Grompone von Gioi, Rafael; Monasse, Pascal; Morel, Jean-Michel

    2012-10-01

    This paper addresses the high precision measurement of the distortion of a digital camera from photographs. Traditionally, this distortion is measured from photographs of a flat pattern which contains aligned elements. Nevertheless, it is nearly impossible to fabricate a very flat pattern and to validate its flatness. This fact limits the attainable measurable precisions. In contrast, it is much easier to obtain physically very precise straight lines by tightly stretching good quality strings on a frame. Taking literally "plumb-line methods", we built a "calibration harp" instead of the classic flat patterns to obtain a high precision measurement tool, demonstrably reaching 2/100 pixel precisions. The harp is complemented with the algorithms computing automatically from harp photographs two different and complementary lens distortion measurements. The precision of the method is evaluated on images corrected by state-of-the-art distortion correction algorithms, and by popular software. Three applications are shown: first an objective and reliable measurement of the result of any distortion correction. Second, the harp permits to control state-of-the art global camera calibration algorithms: It permits to select the right distortion model, thus avoiding internal compensation errors inherent to these methods. Third, the method replaces manual procedures in other distortion correction methods, makes them fully automatic, and increases their reliability and precision.

  15. High Resolution and High Precision-Spectroscopy with HARPS

    NASA Astrophysics Data System (ADS)

    Pepe, F.; Lovis, C.

    Extra-solar planet search at a level of precision below 1 ms-1 sets strong requirements to the quality and stability of the wavelength solution. It also forces us to understand the effects of instrumental stability, on the one hand, and the quality of the wavelength reference, on the other hand, since both will have an impact, although in a different way, on the short- and long-term precision of the instrument. This chapter presents the calibration principles of HARPS, which lead to its extra-ordinary wavelength solution and, as a direct consequence, to its unique radial-velocity precision. In particular it will focus on the improvements of the thorium-lamp calibrations we made during the past three years, but it willl also discuss the present limitations. Finally, we give an outlook on further possible improvements which can be made in view of the extreme precision required by instruments like CODEX@ELT.

  16. High precision spectroscopy and imaging in THz frequency range

    NASA Astrophysics Data System (ADS)

    Vaks, Vladimir L.

    2014-03-01

    Application of microwave methods for development of the THz frequency range has resulted in elaboration of high precision THz spectrometers based on nonstationary effects. The spectrometers characteristics (spectral resolution and sensitivity) meet the requirements for high precision analysis. The gas analyzers, based on the high precision spectrometers, have been successfully applied for analytical investigations of gas impurities in high pure substances. These investigations can be carried out both in absorption cell and in reactor. The devices can be used for ecological monitoring, detecting the components of chemical weapons and explosive in the atmosphere. The great field of THz investigations is the medicine application. Using the THz spectrometers developed one can detect markers for some diseases in exhaled air.

  17. Radiometric Navigation Update

    NASA Astrophysics Data System (ADS)

    Nettles, James L.; Witsmeer, A. James; Wilt, Robert E.

    1980-12-01

    Boeing Aerospace Company (BAC) of Seattle, Washington and Sperry Microwave Electronics of Clearwater, Florida have developed a multiple-beam radiometric navigation update system. This paper describes the system design, flight test program, and preliminary results. The system was designed and its performance evaluated using analytically derived formulas for performance measures and detailed Monte Carlo simulations. As a result BAC recommended a five or seven fixed beam radiometer. Sperry built a seven-beam, 35 GHz radiometer which BAC flight tested in 1979 to demonstrate its effectiveness over a variety of test scenes under various environmental conditions. Four scenes were selected for the flight test varying from land-water to highly forested regions. Preliminary analysis of the flight test results confirm the expected performance improvement over the single-fixed-beam system tested in 1975. This approach to a terrain sensing millimeter wave radiometer would be applicable to low altitude penetrating aircraft. The system is low cost, with no moving parts; low volume, requiring only a single receiver with small wide-beam antennas; and stealthy, being completely passive. Radiometry can also be complementary to todays terrain correlation approach since flat areas usually contain a maximum of cultural features; where one system works poorly the other works well. This test program provides a data base for studying a wide variety of pattern matching and correlation algorithms, with and without attitude compensation, and using various subsets of the full seven-beam combination.

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

    SciTech Connect

    Kolodner, Paul

    2014-05-15

    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%.

  19. Design and control of a high precision drive mechanism

    NASA Astrophysics Data System (ADS)

    Pan, Bo; He, Yongqiang; Wang, Haowei; Zhang, Shuyang; Zhang, Donghua; Wei, Xiaorong; Jiang, Zhihong

    2017-01-01

    This paper summarizes the development of a high precision drive mechanism (HPDM) for space application, such as the directional antenna, the laser communication device, the mobile camera and other pointing mechanisms. In view of the great practical significance of high precision drive system, control technology for permanent magnet synchronous motor (PMSM) servo system is also studied and a PMSM servo controller is designed in this paper. And the software alignment was applied to the controller to eliminate the steady error of the optical encoder, which helps to realize the 1 arcsec (1σ) control precision. To assess its capabilities, the qualification environment testing including the thermal vacuum cycling testing, and the sinusoidal and random vibration were carried out. The testing results show that the performance of the HPDM is almost the same between the former and the end of each testing.

  20. High-precision spectroscopy of hydrogen molecular ions

    NASA Astrophysics Data System (ADS)

    Zhong, Zhen-Xiang; Tong, Xin; Yan, Zong-Chao; Shi, Ting-Yun

    2015-05-01

    In this paper, we overview recent advances in high-precision structure calculations of the hydrogen molecular ions ( and HD+), including nonrelativistic energy eigenvalues and relativistic and quantum electrodynamic corrections. In combination with high-precision measurements, it is feasible to precisely determine a molecular-based value of the proton-to-electron mass ratio. An experimental scheme is presented for measuring the rovibrational transition frequency (v,L) : (0,0) → (6,1) in HD+, which is currently underway at the Wuhan Institute of Physics and Mathematics. Project supported by the National Natural Science Foundation of China (Grants Nos. 11474316, 11004221, 10974224, and 11274348), the “Hundred Talent Program” of Chinese Academy of Sciences. Yan Zong-Chao was supported by NSERC, SHARCnet, ACEnet of Canada, and the CAS/SAFEA International Partnership Program for Creative Research Teams.

  1. Precision glass molding: an integrative approach for the production of high precision micro-optics

    NASA Astrophysics Data System (ADS)

    Hünten, Martin; Klocke, Fritz; Dambon, Olaf

    2010-02-01

    Miniaturization and integration are the dominating factors for the success of numerous optical devices. Conventional manufacturing processes for the fabrication of precise glass optics by means of grinding and polishing cannot cope the increasing demands in terms of precision, volume and costs. Here, precision glass molding is the enabling technology to meet these demands of the future optical products and applications. Since the market requests further miniaturization and integration of the micro optical components the possession of the entire sequence of processes is absolutely essential. With the accomplished and ongoing developments at the Fraunhofer IPT, the replication of double-sided (a)spherical and (a)cylindrical glass lenses with form accuracies of < 150 nm as well as lens arrays and even freeform optics could be realized. Therefore, a sequence of processes needs to be passed. The FEM-simulation of the molding process which was driven to a point capable to simulate even the molding of freeform optics is the first process step. Further on, new mold design concepts were generated to enable the replication of free formed optics. The research works focusing on the mold manufacturing led to sophisticated grinding process strategies able to realized complex mold geometries such as lens arrays. With regard to the coating of the molds, proceedings were developed assuring a defect free and uniform coating which enables the longevity of the molds and therewith helps reducing the final costs per lens. Thus, the precision glass molding becomes more and more interesting even for highly complex mid volume lots, characteristic for European or US optics manufacturer.

  2. High precision radial velocities: the case for NIR.

    NASA Astrophysics Data System (ADS)

    Carleo, I.; Gratton, R.

    In the context of the preparation for the high resolution spectrograph HIRES for E-ELT, we are studying the possibility to derive high-precision radial velocities (RV) on a prototype:GIANO, the near-infrared (NIR) echelle spectrograph now available at the Telescopio Nazionale Galileo. Radial velocities measured from near-infrared spectra are a potential tool to search for extrasolar planets around cool stars. High resolution infrared spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. In particular, no other IR instruments have GIANO's capability to cover the entire NIR wavelength range. We have developed an ensemble of IDL procedures to measure high precision radial velocities on GIANO spectra. Taking into account the achieved precisions with GIANO, we constrain the sample of targets for which GIANO is better than HARPS-N, but with the advent of GIARPS (GIANO+HARPS-N), GIANO will improve its performances and include a much larger sample of stars. The NIR range is the future of RV measurements, especially because the jitter due to the star surface activities is reduced in the NIR. As a consequence, HIRES working in NIR range might be very useful, and for a wide range of cases, it will be more efficient than HIRES working in the visible range, for detection and characterization of planets using radial velocity technique.

  3. A Sounding Rocket Mission Concept to Acquire High-Resolution Radiometric Spectra Spanning the 9 nm - 31 nm Wavelength Range

    NASA Technical Reports Server (NTRS)

    Krause, L. Habash; Cirtain, Jonathan; McGuirck, Michael; Pavelitz, Steven; Weber, Ed.; Winebarger, Amy

    2012-01-01

    When studying Solar Extreme Ultraviolet (EUV) emissions, both single-wavelength, two- dimensional (2D) spectroheliograms and multi-wavelength, one-dimensional (1D) line spectra are important, especially for a thorough understanding of the complex processes in the solar magnetized plasma from the base of the chromosphere through the corona. 2D image data are required for a detailed study of spatial structures, whereas radiometric (i.e., spectral) data provide information on relevant atomic excitation/ionization state densities (and thus temperature). Using both imaging and radiometric techniques, several satellite missions presently study solar dynamics in the EUV, including the Solar Dynamics Observatory (SDO), Hinode, and the Solar-Terrestrial Relations Observatory (STEREO). The EUV wavelengths of interest typically span 9 nm to 31 nm, with the shorter wavelengths being associated with the hottest features (e.g., intense flares and bright points) and the longer wavelengths associated with cooler features (e.g., coronal holes and filaments). Because the optical components of satellite instruments degrade over time, it is not uncommon to conduct sounding rocket underflights for calibration purposes. The authors have designed a radiometric sounding rocket payload that could serve as both a calibration underflight for and a complementary scientific mission to the upcoming Solar Ultraviolet Imager (SUVI) mission aboard the GOES-R satellite (scheduled for a 2015 launch). The challenge to provide quality radiometric line spectra over the 9-31 nm range covered by SUVI was driven by the multilayer coatings required to make the optical components, including mirrors and gratings, reflective over the entire range. Typically, these multilayers provide useful EUV reflectances over bandwidths of a few nm. Our solution to this problem was to employ a three-telescope system in which the optical components were coated with multilayers that spanned three wavelength ranges to cover

  4. Uncooled radiometric camera performance

    NASA Astrophysics Data System (ADS)

    Meyer, Bill; Hoelter, T.

    1998-07-01

    Thermal imaging equipment utilizing microbolometer detectors operating at room temperature has found widespread acceptance in both military and commercial applications. Uncooled camera products are becoming effective solutions to applications currently using traditional, photonic infrared sensors. The reduced power consumption and decreased mechanical complexity offered by uncooled cameras have realized highly reliable, low-cost, hand-held instruments. Initially these instruments displayed only relative temperature differences which limited their usefulness in applications such as Thermography. Radiometrically calibrated microbolometer instruments are now available. The ExplorIR Thermography camera leverages the technology developed for Raytheon Systems Company's first production microbolometer imaging camera, the Sentinel. The ExplorIR camera has a demonstrated temperature measurement accuracy of 4 degrees Celsius or 4% of the measured value (whichever is greater) over scene temperatures ranges of minus 20 degrees Celsius to 300 degrees Celsius (minus 20 degrees Celsius to 900 degrees Celsius for extended range models) and camera environmental temperatures of minus 10 degrees Celsius to 40 degrees Celsius. Direct temperature measurement with high resolution video imaging creates some unique challenges when using uncooled detectors. A temperature controlled, field-of-view limiting aperture (cold shield) is not typically included in the small volume dewars used for uncooled detector packages. The lack of a field-of-view shield allows a significant amount of extraneous radiation from the dewar walls and lens body to affect the sensor operation. In addition, the transmission of the Germanium lens elements is a function of ambient temperature. The ExplorIR camera design compensates for these environmental effects while maintaining the accuracy and dynamic range required by today's predictive maintenance and condition monitoring markets.

  5. Small satellite radiometric measurements

    SciTech Connect

    Weber, P.G.

    1991-01-01

    A critical need for the Mission to Planet Earth is to provide continuous, well-calibrated radiometric data for the radiation budget. This paper describes a new, compact, flexible radiometer which will provide both spectrally integrated data and data in selected spectral bands. The radiometer design is suitable for use on small satellites, aircraft, or remotely piloted vehicles (RPVs). 12 refs., 2 figs.

  6. Radiometric Dating Does Work!

    ERIC Educational Resources Information Center

    Dalrymple, G. Brent

    2000-01-01

    Discusses the accuracy of dating methods and creationist arguments that radiometric dating does not work. Explains the Manson meteorite impact and the Pierre shale, the ages of meteorites, the K-T tektites, and dating the Mount Vesuvius eruption. (Author/YDS)

  7. Radiometric Dating Does Work!

    ERIC Educational Resources Information Center

    Dalrymple, G. Brent

    2000-01-01

    Discusses the accuracy of dating methods and creationist arguments that radiometric dating does not work. Explains the Manson meteorite impact and the Pierre shale, the ages of meteorites, the K-T tektites, and dating the Mount Vesuvius eruption. (Author/YDS)

  8. Photovoltaics radiometric issues and needs

    SciTech Connect

    Myers, D.R.

    1995-11-01

    This paper presents a summary of issues discussed at the photovoltaic radiometric measurements workshop. Topics included radiometric measurements guides, the need for well-defined goals, documentation, calibration checks, accreditation of testing laboratories and methods, the need for less expensive radiometric instrumentation, data correlations, and quality assurance.

  9. Electric Quadrupole Transition Measurements of Hydrogen Molecule with High Precision

    NASA Astrophysics Data System (ADS)

    Cheng, Cun-Feng; Wang, Jin; Tan, Yan; Liu, An-Wen; Hu, Shui-Ming

    2013-06-01

    Molecular hydrogen is the most fundamental, and the only neutral molecule expected to be both calculated and measured with extremely high accuracy. High-precision measurements of its spectroscopy, especially the levels at the electric ground state, play an important role in the examination of precise quantum chemistry calculations and some fundamental physical constants. In the infrared region, H_2, being a homonuclear diatomic molecule, only has very weak electric quadrupole transitions. We established a new spectroscopy approach with ultra-high precision and sensitivity as well, based on a laser-locked cavity ring-down spectrometer. An equivalent absorption path-length of thousands of kilometers and a frequency precision of 10^{-5} cm^{-1} have been achieved. Ro-vibrational spectra of the second overtone of H_2 have been recorded. The obtained results will provide a direct examination of the high-accuracy quantum theory. It also shades light on the determination of fundamental physical constants such as the electron/proton mass ratio in a molecular system.

  10. VIEW OF MICROMACHINING, HIGH PRECISION EQUIPMENT USED TO CUSTOM MAKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF MICRO-MACHINING, HIGH PRECISION EQUIPMENT USED TO CUSTOM MAKE SMALL PARTS. LUMPS OF CLAY; SHOWN IN THE PHOTOGRAPH, WERE USED TO STABILIZE PARTS BEING MACHINED. (11/1/87) - Rocky Flats Plant, Stainless Steel & Non-Nuclear Components Manufacturing, Southeast corner of intersection of Cottonwood & Third Avenues, Golden, Jefferson County, CO

  11. Fabrication and metrology of high-precision freeform surfaces

    NASA Astrophysics Data System (ADS)

    Supranowitz, Chris; Dumas, Paul; Nitzsche, Tobias; DeGroote Nelson, Jessica; Light, Brandon B.; Medicus, Kate; Smith, Nathan

    2013-09-01

    Freeform applications are growing and include helmet-mounted displays, conformal optics (e.g. windows integrated into airplane wings), and those requiring the extreme precision of EUV. These non-rotationally symmetric surfaces pose challenges to optical fabrication, mostly in the areas of polishing and metrology. The varying curvature of freeform surfaces drives the need for smaller, more "conformal", tools for polishing and reference beams for interferometry. In this paper, we present fabrication results of a high-precision freeform surface. We will discuss the total manufacturing process, including generation, pre-polishing, MRF®, and metrology, highlighting the capabilities available in today's optical fabrication companies.

  12. GENERATION AND CONTROL OF HIGH PRECISION BEAMS AT LEPTON ACCELERATORS

    SciTech Connect

    Yu-Chiu Chao

    2007-06-25

    Parity violation experiments require precision manipulation of helicity-correlated beam coordinates on target at the nm/nrad-level. Achieving this unprecedented level of control requires a detailed understanding of the particle optics and careful tuning of the beam transport to keep anomalies from compromising the design adiabatic damping. Such efforts are often hindered by machine configuration and instrumentation limitations at the low energy end. A technique has been developed at CEBAF including high precision measurements, Mathematica-based analysis for obtaining corrective solutions, and control hardware/software developments for realizing such level of control at energies up to 5 GeV.

  13. High precision u/th dating of first Polynesian settlement.

    PubMed

    Burley, David; Weisler, Marshall I; Zhao, Jian-xin

    2012-01-01

    Previous studies document Nukuleka in the Kingdom of Tonga as a founder colony for first settlement of Polynesia by Lapita peoples. A limited number of radiocarbon dates are one line of evidence supporting this claim, but they cannot precisely establish when this event occurred, nor can they afford a detailed chronology for sequent occupation. High precision U/Th dates of Acropora coral files (abraders) from Nukuleka give unprecedented resolution, identifying the founder event by 2838±8 BP and documenting site development over the ensuing 250 years. The potential for dating error due to post depositional diagenetic alteration of ancient corals at Nukuleka also is addressed through sample preparation protocols and paired dates on spatially separated samples for individual specimens. Acropora coral files are widely distributed in Lapita sites across Oceania. U/Th dating of these artifacts provides unparalleled opportunities for greater precision and insight into the speed and timing of this final chapter in human settlement of the globe.

  14. The advancement of the high precision stress polishing

    NASA Astrophysics Data System (ADS)

    Li, Chaoqiang; Lei, Baiping; Han, Yu

    2016-10-01

    The stress polishing is a kind of large-diameter aspheric machining technology with high efficiency. This paper focuses on the principle, application in the processing of large aspheric mirror, and the domestic and foreign research status of stress polishing, aimed at the problem of insufficient precision of mirror surface deformation calculated by some traditional theories and the problem that the output precision and stability of the support device in stress polishing cannot meet the requirements. The improvement methods from these three aspects are put forward, the characterization method of mirror's elastic deformation in stress polishing, the deformation theory of influence function and the calculation of correction force, the design of actuator's mechanical structure. These improve the precision of stress polishing and provide theoretical basis for the further application of stress polishing in large-diameter aspheric machining.

  15. High Precision Differential Photometry with CCDs: A Brief History

    NASA Astrophysics Data System (ADS)

    Howell, Steve B.

    I present a brief history of the hunt for high photometric precision using CCDs in astronomy. CCDs were invented in 1969 and only 7 years later they started to appear at the major observatories of the time. The next 10 years constituted a steep learning curve for astronomers as they developed an understanding of CCDs as instruments and analysis techniques for use with digital images. In 1985, differential photometry with CCDs began producing light curves with precisions near 0.01 magnitude. By 2008, ground-based telescopes armed with CCDs and using differential techniques consistently can provide photometric precisions of 1 millimagnitude or better. The challenge now is to continue to improve the photometry using new types of CCD detectors and other advanced digital imagers.

  16. Precision glass molding of high-resolution diffractive optical elements

    NASA Astrophysics Data System (ADS)

    Prater, Karin; Dukwen, Julia; Scharf, Toralf; Herzig, Hans P.; Plöger, Sven; Hermerschmidt, Andreas

    2016-04-01

    The demand of high resolution diffractive optical elements (DOE) is growing. Smaller critical dimensions allow higher deflection angles and can fulfill more demanding requirements, which can only be met by using electron-beam lithography. Replication techniques are more economical, since the high cost of the master can be distributed among a larger number of replicas. The lack of a suitable mold material for precision glass molding has so far prevented an industrial use. Glassy Carbon (GC) offers a high mechanical strength and high thermal strength. No anti-adhesion coatings are required in molding processes. This is clearly an advantage for high resolution, high aspect ratio microstructures, where a coating with a thickness between 10 nm and 200 nm would cause a noticeable rounding of the features. Electron-beam lithography was used to fabricate GC molds with highest precision and feature sizes from 250 nm to 2 μm. The master stamps were used for precision glass molding of a low Tg glass L-BAL42 from OHARA. The profile of the replicated glass is compared to the mold with the help of SEM images. This allows discussion of the max. aspect-ratio and min. feature size. To characterize optical performances, beamsplitting elements are fabricated and their characteristics were investigated, which are in excellent agreement to theory.

  17. Radiometric flight results from the HyperSpectral Imager for Climate Science (HySICS)

    NASA Astrophysics Data System (ADS)

    Kopp, Greg; Smith, Paul; Belting, Chris; Castleman, Zach; Drake, Ginger; Espejo, Joey; Heuerman, Karl; Lanzi, James; Stuchlik, David

    2017-04-01

    Long-term monitoring of the Earth-reflected solar spectrum is necessary for discerning and attributing changes in climate. High radiometric accuracy enables such monitoring over decadal timescales with non-overlapping instruments, and high precision enables trend detection on shorter timescales. The HyperSpectral Imager for Climate Science (HySICS) is a visible and near-infrared spatial/spectral imaging spectrometer intended to ultimately achieve ˜ 0.2 % radiometric accuracies of Earth scenes from space, providing an order-of-magnitude improvement over existing space-based imagers. On-orbit calibrations from measurements of spectral solar irradiances acquired by direct views of the Sun enable radiometric calibrations with superior long-term stability than is currently possible with any manmade spaceflight light source or detector. Solar and lunar observations enable in-flight focal-plane array (FPA) flat-fielding and other instrument calibrations. The HySICS has demonstrated this solar cross-calibration technique for future spaceflight instrumentation via two high-altitude balloon flights. The second of these two flights acquired high-radiometric-accuracy measurements of the ground, clouds, the Earth's limb, and the Moon. Those results and the details of the uncertainty analyses of those flight data are described.

  18. High Precision Photometry for the K2 Mission

    NASA Astrophysics Data System (ADS)

    Huang, Xu; Soares-Furtado, Melinda; Penev, Kaloyan; Hartman, Joel; Bakos, Gaspar; Bhatti, Waqas; Domsa, Istvan; de Val-Borro, Miguel

    2015-12-01

    The two reaction wheel K2 mission brings new challenges for the data reduction processes. We developed a reduction pipeline for extracting high precision photometry from the K2 dataset and we use this pipeline to generate light curves for the K2 Campaign 0 super-stamps and K2 Campaign 1 target pixel dataset. Key to our reduction technique is the derivation of global astrometric solutions from the target stamps from which accurate centroids are passed on for high precision photometry extraction. We also implemented the image subtraction method to reduce the K2 Campaign 0 super-stamps containing open clusters M35 and NGC2158. We extract target light curvesfor sources from a combined UCAC4 and EPIC catalogue -- this includes not only primary targets of the K2 Mission, but also other stars that happen to fall on the pixel stamps. Our astrometric solutions achieve a median residual of ~0.127". For bright stars, our best 6.5 hour precision for raw light curves is ~20 parts per million (ppm). For our detrended light curves, the best 6.5 hour precision achieved is ~15 ppm. We show that our detrended light curves have fewer systematic effects (or trends, or red-noise) than light curves produced by other groups from the same observations. We highlight the measurements of rotation curves using the K2 light curves of stars within open cluster M35 and NGC2158.

  19. Design of high-precision ranging system for laser fuze

    NASA Astrophysics Data System (ADS)

    Chen, Shanshan; Zhang, He; Xu, Xiaobin

    2016-10-01

    According to the problem of the high-precision ranging in the circumferential scanning probe laser proximity fuze, a new type of pulsed laser ranging system has been designed. The laser transmitting module, laser receiving module and ranging processing module have been designed respectively. The factors affecting the ranging accuracy are discussed. And the method of improving the ranging accuracy is studied. The high-precision ranging system adopts the general high performance microprocessor C8051FXXX as the core. And the time interval measurement chip TDC-GP21 was used to implement the system. A PCB circuit board was processed to carry on the experiment. The results of the experiment prove that a centimeter level accuracy ranging system has been achieved. The works can offer reference for ranging system design of the circumferential scanning probe laser proximity fuze.

  20. High-precision Photogrammetric Surface Figure Measurements under Cryogenic Environment

    NASA Astrophysics Data System (ADS)

    Lou, Z.; Qian, Y.; Fan, S. H.; Liu, C. R.; Wang, H. R.; Zuo, Y. X.; Cheng, J. Q.; Yang, J.

    2016-01-01

    Limited by the working temperature of the measurement equipments, most of the high-precision surface figure measurement techniques cannot be applied under a cryogenic environment. This paper reports the first attempt to measure the surface figure of a high-precision terahertz reflector panel under low temperatures based on photogrammetry. The measurement employs a high resolution industrial camera sitting on an automatic experimental platform which enables photos been taken in an automatic fashion inside a climate chamber. A repeatable accuracy of 2.1 μm rms is achieved under the cryogenic environment. Furthermore, surface figure measured by a three-coordinate measuring machine under room temperature is used to calibrate the thickness variation of the paper targets. By this technique, the surface figure of an aluminum prototype panel of the 5 meter Dome A Terahertz Telescope (DATE5) is measured from room temperature down to -55°C.

  1. Preparation of cold molecules for high-precision measurements

    NASA Astrophysics Data System (ADS)

    Wall, T. E.

    2016-12-01

    Molecules can be used to test fundamental physics. Such tests often require cold molecules for detailed spectroscopic analysis. Cooling internal degrees of freedom provides a high level of state-selectivity, with large populations in the molecular states of interest. Cold translational motion allows slow, bright beams to be created, allowing long interaction times. In this tutorial article we describe the common techniques for producing cold molecules for high-precision spectroscopy experiments. For each technique we give examples of its application in experiments that use molecular structure to probe fundamental physics, choosing one experiment in particular as a case study. We then discuss a number of new techniques, some currently under development, others proposed, that promise high flux sources of cold molecules applicable to precise spectroscopic tests of fundamental physics.

  2. NASA IKONOS Multispectral Radiometric Calibration and 3-Year Temporal Stability Assessment

    NASA Technical Reports Server (NTRS)

    Pagnutti, Mary; Carver, David; Holekamp, Kara; Ryan, Robert; Zanoni, Vicki; Thome, Kurtis; Schiller, Stephen; Aaran, David

    2003-01-01

    Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities can place confidence in the imagery they use and can fully understand its properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other system. In addition, the user community has little or no insight into the design and operation of commercial sensors or into the methods involved in generating commercial products. To address this calibration need, the NASA Stennis Space Center (SSC) Earth Science Applications (ESA) Directorate established a commercial satellite imaging radiometric calibration team consisting of three independent groups: NASA, SSC,ESA, the University of Arizona Remote Sensing Group, and South Dacota State University. Each group determined the absolute radiometric calibration coefficients of the Space Imaging IKONOS 4-band, 4 m multispectral product covering the visible through near-infrared spectral region. For a three year period beginning in 2000, each team employed some variant of a reflectance-based vicarious calibration approach, requiring ground-based measurements coincident with IKONOS image acquisitions and radiative transfer calculations. Several study sites throughout the United States were employed that covered nearly the entire dynamic range of the IKONOS sensor. IKONOS at-sensor radiance values were compared to those estimated by each independent group to determine the IKONOS sensor's radiometric accuracy and stability. Over 10 individual vicariously determined at-sensor radiance estimates were used each year. When combined, these estimates provided a high-precision radiometric gain calibration coefficient. No significant calibration offset was observed. The results of this evaluation provide the scientific community with an independent assessment of the IKONOS sensor's absolute calibration and temporal stability over the 3

  3. Highly precise and compact ultrahigh vacuum rotary feedthrough

    NASA Astrophysics Data System (ADS)

    Aiura, Y.; Kitano, K.

    2012-03-01

    The precision and rigidity of compact ultrahigh vacuum (UHV) rotary feedthroughs were substantially improved by preparing and installing an optimal crossed roller bearing with mounting holes. Since there are mounting holes on both the outer and inner races, the bearing can be mounted directly to rotary and stationary stages without any fixing plates and housing. As a result, it is possible to increase the thickness of the bearing or the size of the rolling elements in the bearing without increasing the distance between the rotating and fixing International Conflat flanges of the UHV rotary feedthrough. Larger rolling elements enhance the rigidity of the UHV rotary feedthrough. Moreover, owing to the structure having integrated inner and outer races and mounting holes, the performance is almost entirely unaffected by the installation of the bearing, allowing for a precise optical encoder to be installed in the compact UHV rotary feedthrough. Using position feedback via a worm gear system driven by a stepper motor and a precise rotary encoder, the actual angle of the compact UHV rotary feedthrough can be controlled with extremely high precision.

  4. Flight Test Performance of a High Precision Navigation Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Pierrottet, Diego; Amzajerdian, Farzin; Petway, Larry; Barnes, Bruce; Lockard, George

    2009-01-01

    A navigation Doppler Lidar (DL) was developed at NASA Langley Research Center (LaRC) for high precision velocity measurements from a lunar or planetary landing vehicle in support of the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. A unique feature of this DL is that it has the capability to provide a precision velocity vector which can be easily separated into horizontal and vertical velocity components and high accuracy line of sight (LOS) range measurements. This dual mode of operation can provide useful information, such as vehicle orientation relative to the direction of travel, and vehicle attitude relative to the sensor footprint on the ground. System performance was evaluated in a series of helicopter flight tests over the California desert. This paper provides a description of the DL system and presents results obtained from these flight tests.

  5. High-precision buffer circuit for suppression of regenerative oscillation

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Hare, David A.; Tcheng, Ping

    1995-01-01

    Precision analog signal conditioning electronics have been developed for wind tunnel model attitude inertial sensors. This application requires low-noise, stable, microvolt-level DC performance and a high-precision buffered output. Capacitive loading of the operational amplifier output stages due to the wind tunnel analog signal distribution facilities caused regenerative oscillation and consequent rectification bias errors. Oscillation suppression techniques commonly used in audio applications were inadequate to maintain the performance requirements for the measurement of attitude for wind tunnel models. Feedback control theory is applied to develop a suppression technique based on a known compensation (snubber) circuit, which provides superior oscillation suppression with high output isolation and preserves the low-noise low-offset performance of the signal conditioning electronics. A practical design technique is developed to select the parameters for the compensation circuit to suppress regenerative oscillation occurring when typical shielded cable loads are driven.

  6. High Precision Measurement of the ^19Ne Lifetime

    NASA Astrophysics Data System (ADS)

    Broussard, Leah; Back, H. O.; Boswell, M. S.; Crowell, A. S.; Howell, C. R.; Kidd, M. F.; Pattie, R. W., Jr.; Young, A. R.; Dendooven, P. G.; Giri, G. S.; van der Hoek, D. J.; Jungmann, K.; Kruithof, W. L.; Onderwater, C. J. G.; Santra, B.; Shidling, P. D.; Sohani, M.; Versolota, O. O.; Willmann, L.; Wilschut, H. W.

    2009-10-01

    Recently, a rigorous review of the T=12 mirror transitions has identified several systems which can contribute to high precision tests exploring deviations from the Standard Model's description of the electroweak interaction. Arguably, one of the best candidates is the &+circ; decay of ^19Ne to ^19F. In this system, the main contribution to the uncertainty of extracted Standard Model parameters is due to the measured value of the lifetime of the decay. In March 2009, a high precision measurement of the lifetime of ^19Ne was made by a collaboration between the Triangle Universities Nuclear Laboratory (TUNL) and the Kernfysisch Versneller Instituut (KVI) at the Trapped Radioactive Isotopes: Microlaboratories for Fundamental Physics (Triμp) facility. An overview of the experiment and preliminary results will be presented.

  7. A high-precision polarimeter for small telescopes

    NASA Astrophysics Data System (ADS)

    Bailey, Jeremy; Cotton, Daniel V.; Kedziora-Chudczer, Lucyna

    2017-02-01

    We describe Mini-HIPPI (Miniature HIgh Precision Polarimetric Instrument), a stellar polarimeter weighing just 650 gm but capable of measuring linear polarization to ∼10-5. Mini-HIPPI is based on the use of a Ferroelectric Liquid Crystal modulator. It can easily be mounted on a small telescope and allows us to study the polarization of bright stars at levels of precision which are hitherto largely unexplored. We present results obtained with Mini-HIPPI on a 35-cm telescope. Measurements of polarized standard stars are in good agreement with predicted values. Measurements of a number of bright stars agree well with those from other high-sensitivity polarimeters. Observations of the binary system Spica show polarization variability around the orbital cycle.

  8. High-precision Velocimetry Reveals δ Cephei's Secret Companion

    NASA Astrophysics Data System (ADS)

    Anderson, Richard I.; Sahlmann, Johannes; Holl, Berry; Eyer, Laurent

    2015-08-01

    The search for extra-solar planets has driven tremendous improvements in the precision of radial velocities measured with high-resolution echelle spectrographs. However, relatively few studies have as of yet exploited the present-day extreme (m/s) instrumental precision to study Cepheid variable stars.We have been observing the prototype of classical Cepheids, δ Cephei, since September 2011 using the HERMES spectrograph mounted to the Mercator telescope located at the Roque de los Muchachos Observatory on the island of La Palma. Being one of the most-studied variable stars, we originally chose δ Cephei as a maximum-precision reference for other Cepheids in our sample. To our great surprise however, we discovered a clear orbital signature in the homogeneous HERMES data. Adding in radial velocity data from the literature, we then determined δ Cephei's orbit (cf. Anderson et al. 2015, arXiv:1503.04116). The high orbital eccentricity (e=0.647) leads to close pericenter passages (rmin ~ 9.5 RδCep) which suggest an intriguing past that requires further study, since Cepheids are well-known magnifying glasses for stellar evolution (Kippenhahn & Weigert 1994). We furthermore determined a new parallax to δ Cephei (using Hipparcos data) that is in tension with previous estimates and shows that the orbit will have to be accounted for when measuring δ Cephei's parallax with Gaia.While some of our HERMES data are as precise as 9 m/s, we found correlated excess residuals when removing the reference pulsation model and orbital motion from the HERMES radial velocity data, leaving an RMS of 47 m/s. These higher-than-expected residuals are reminiscent of the "period-jitter" or "flickering" observed in high-precision photometry of Cepheids obtained with the Kepler and MOST satellites. This reveals a fortuitous synergy between variable stars studies and the field of exoplanet research and opens the window for a better understanding of Cepheid pulsations via high-precision

  9. Dipole model analysis of high precision HERA data

    NASA Astrophysics Data System (ADS)

    Luszczak, A.; Kowalski, H.

    2014-04-01

    We analyze, within a dipole model, the inclusive deep inelastic scattering cross section data, obtained from the combination of the measurements of the H1 and ZEUS experiments performed at the HERA collider. We show that these high precision data are very well described within the dipole model framework, which is complemented with valence quark structure functions. We discuss the properties of the gluon density obtained in this way.

  10. High precision tide spectroscopy. [using the superconducting gravimeter

    NASA Technical Reports Server (NTRS)

    Goodkind, J. M.

    1978-01-01

    Diurnal and long period earth tides were measured to high accuracy and precision with the superconducting gravimeter. The results provide new evidence on the geophysical questions which have been attacked through earth tide measurements in the past. In addition, they raise new questions of potential interest. Slow fluctuations in gravity of order 10 micron gal over periods of 3 to 5 months were observed and are discussed.

  11. High-Precision Direct Method for the Radiative Transfer Problems

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Hou, Su-Qing; Yang, Ping; Wu, Kai-Su

    2013-06-01

    It is the main aim of this paper to investigate the numerical methods of the radiative transfer equation. Using the five-point formula to approximate the differential part and the Simpson formula to substitute for integral part respectively, a new high-precision numerical scheme, which has 4-order local truncation error, is obtained. Subsequently, a numerical example for radiative transfer equation is carried out, and the calculation results show that the new numerical scheme is more accurate.

  12. High-Precision Computation: Mathematical Physics and Dynamics

    SciTech Connect

    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.

  13. Photonic systems for high precision radial velocity measurements

    NASA Astrophysics Data System (ADS)

    Halverson, Samuel P.

    The discovery of Earth-like exoplanets has profound implications for our understanding of the origins and diversity of life in our universe. As such, developing new and improved Doppler radial velocity (RV) spectrometers capable of discovering and characterizing these planets is a high priority in the astronomical community. However, detection of true Earth-analogs remains beyond the technical reach of current Doppler RV instruments. This thesis discusses a number of technological developments designed specifically to overcome classical instrumental limitations of high precision Doppler RV measurements. These technologies are essential components of next generation instruments that aim to achieve the RV precision necessary to detect low-mass planets. This instrumentation research is driven by the development of the Habitable-zone Planet Finder (HPF), a near-infrared (NIR) Doppler spectrograph currently under development at Penn State that will detect terrestrial-mass planets orbiting nearby M-dwarfs. Furthermore, many technologies discussed will also be applied to the NASA-NSF Extreme Precision Doppler Spectrometer concept NEID, a Doppler RV instrument for the 3.5 meter WIYN telescope, slated for delivery in 2019. NEID is an ultra-stable, high resolution optical spectrometer also under development at Penn State. This thesis describes new specialized optical fiber delivery systems, designed to significantly improve instrument illumination stability, modal noise suppression systems, which suppress mode interference in optical fibers and allow spectrometers to fully realize the exquisite precision of modern wavelength calibration sources, and new photonic calibration sources, which show significant promise as potential Doppler wavelength references. These technologies represent important steps in enabling next generation instruments to reach precisions sufficient to detect terrestrial-mass planets orbiting in the Habitable-zones of nearby stars. Improving measurement

  14. High precision capacitive beam phase probe for KHIMA project

    NASA Astrophysics Data System (ADS)

    Hwang, Ji-Gwang; Yang, Tae-Keun; Forck, Peter

    2016-11-01

    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.

  15. Automated high precision secondary pH measurements

    NASA Astrophysics Data System (ADS)

    Bastkowski, F.; Jakobsen, P. T.; Stefan, F.; Kristensen, H. B.; Jensen, H. D.; Kawiecki, R.; Wied, C. E.; Kauert, A.; Seidl, B.; Spitzer, P.; Eberhardt, R.; Adel, B.

    2013-04-01

    A new setup for high precision, automated secondary pH measurements together with a reference measurement procedure has been developed and tested in interlaboratory comparisons using buffers pH 4.005, pH 7.000, and pH 10.012 at 25 °C and 37 °C. Using primary buffers as standards, a standard uncertainty in pH better than 0.005 can be reached. The central measuring device is a one piece, thermostatted cell of PFA (perfluoroalkoxy) with a built-in Hamilton® Single Pore™ Glass electrode. Due to its flow-through principle this device allows pH measurements with low consumption of measurement solutions. The very hydrophobic and smooth PFA as construction material facilitates complete emptying of the cell. Furthermore, the tempering unit affords very precise temperature control and hence contributes to the low target uncertainty of the produced secondary buffer solutions. Use of a symmetric measurement sequence and the two point calibration was sufficient to reach high precision and accuracy.

  16. PHASES High-Precision Differential Astrometry of δ Equulei

    NASA Astrophysics Data System (ADS)

    Muterspaugh, Matthew W.; Lane, Benjamin F.; Konacki, Maciej; Burke, Bernard F.; Colavita, M. M.; Kulkarni, S. R.; Shao, M.

    2005-12-01

    Delta Equulei is among the most well-studied nearby binary star systems. Results of its observation have been applied to a wide range of fundamental studies of binary systems and stellar astrophysics. It is widely used to calibrate and constrain theoretical models of the physics of stars. We report 27 high-precision differential astrometry measurements of δ Equ from the Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES). The median size of the minor axes of the uncertainty ellipses for these measurements is 26 μas. These data are combined with previously published radial velocity data and other previously published differential astrometry measurements using other techniques to produce a combined model for the system orbit. The distance to the system is determined to within one twentieth of a parsec, and the component masses are determined at the level of a percent. The constraints on masses and distance are limited by the precisions of the radial velocity data; we outline plans to improve this deficiency and discuss the outlook for further study of this binary.

  17. Validation of Landsat 7 ETM+ band 6 radiometric performance

    NASA Technical Reports Server (NTRS)

    Palluconi, Frank; Hook, Simon; Abtahi, Ali; Alley, Ron

    2005-01-01

    Since shortly after launch the radiometric performance of band 6 of the ETM+ instrument on Landsat 7 has been evaluated using vicarious calbiration techniques for both land and water targets. This evaluation indicates the radiometric performance of band 6 has been both highly stable and accurate.

  18. Simplified Vicarious Radiometric Calibration

    NASA Technical Reports Server (NTRS)

    Stanley, Thomas; Ryan, Robert; Holekamp, Kara; Pagnutti, Mary

    2010-01-01

    A measurement-based radiance estimation approach for vicarious radiometric calibration of spaceborne multispectral remote sensing systems has been developed. This simplified process eliminates the use of radiative transfer codes and reduces the number of atmospheric assumptions required to perform sensor calibrations. Like prior approaches, the simplified method involves the collection of ground truth data coincident with the overpass of the remote sensing system being calibrated, but this approach differs from the prior techniques in both the nature of the data collected and the manner in which the data are processed. In traditional vicarious radiometric calibration, ground truth data are gathered using ground-viewing spectroradiometers and one or more sun photometer( s), among other instruments, located at a ground target area. The measured data from the ground-based instruments are used in radiative transfer models to estimate the top-of-atmosphere (TOA) target radiances at the time of satellite overpass. These TOA radiances are compared with the satellite sensor readings to radiometrically calibrate the sensor. Traditional vicarious radiometric calibration methods require that an atmospheric model be defined such that the ground-based observations of solar transmission and diffuse-to-global ratios are in close agreement with the radiative transfer code estimation of these parameters. This process is labor-intensive and complex, and can be prone to errors. The errors can be compounded because of approximations in the model and inaccurate assumptions about the radiative coupling between the atmosphere and the terrain. The errors can increase the uncertainty of the TOA radiance estimates used to perform the radiometric calibration. In comparison, the simplified approach does not use atmospheric radiative transfer models and involves fewer assumptions concerning the radiative transfer properties of the atmosphere. This new technique uses two neighboring uniform

  19. Modular Gravitational Reference Sensor for High Precision Astronomical Space Missions

    NASA Astrophysics Data System (ADS)

    Sun, Ke-Xun; Allen, G.; Buchman, S.; Byer, R. L.; Conklin, J. W.; DeBra, D. B.; Gill, D.; Goh, A.; Higuchi, S.; Lu, P.; Robertson, N.; Swank, A.

    2006-12-01

    We review the progress in developing the Modular Gravitational Reference Sensor (modular GRS) [1], which was first proposed as a simplified core sensor for space gravitational wave detection missions. In a modular GRS, laser beam from the remote the sensor does not illuminate the proof mass directly. The internal measurement from housing to proof mass is separated from the external interferometry. A double side grating may further simplify the structure and may better preserve the measurement precision. We review the recent progress in developing modular GRS at Stanford. We have further studied optical sensing design that combines advantage of high precision interferometric measurement and robust optical shadow sensing scheme. We have made critical progress in optical measurement of the center of mass position of a spherical proof mass at a precision without costing the dynamic range while spinning. We have successfully demonstrated the feasibility of fabricating localized grating pattern onto the dielectric and gold materials. We have conducted an initial experiment of rf heterodyne of cavity reflection and thus lowered optical power than that in the direct detection. We have further studied UV LED that will be used for AC charge management experiment. The modular GRS will be an in-time, cost effective product for the advanced Laser Interferometric Space Antenna (LISA) and the Big Bang Observatory (BBO). [1] K. Sun, G. Allen, S. Buchman, D. DeBra, and R. L. Byer, “Advanced Architecture for High Precision Space Laser Interferometers”, 5th International LISA Symposium, ESTEC, Noordwijk, The Netherlands, 12-16 July 2004. Class. Quantum Grav. 22 (2005) S287-S296.

  20. High-precision photometry for K2 Campaign 1

    NASA Astrophysics Data System (ADS)

    Huang, C. X.; Penev, K.; Hartman, J. D.; Bakos, G. Á.; Bhatti, W.; Domsa, I.; de Val-Borro, M.

    2015-12-01

    The two reaction wheel K2 mission promises and has delivered new discoveries in the stellar and exoplanet fields. However, due to the loss of accurate pointing, it also brings new challenges for the data reduction processes. In this paper, we describe a new reduction pipeline for extracting high-precision photometry from the K2 data set, and present public light curves for the K2 Campaign 1 target pixel data set. Key to our reduction is the derivation of global astrometric solutions from the target stamps, from which accurate centroids are passed on for high-precision photometry extraction. We extract target light curves for sources from a combined UCAC4 and EPIC catalogue - this includes not only primary targets of the K2 campaign 1, but also any other stars that happen to fall on the pixel stamps. We provide the raw light curves, and the products of various detrending processes aimed at removing different types of systematics. Our astrometric solutions achieve a median residual of ˜0.127 arcsec. For bright stars, our best 6.5 h precision for raw light curves is ˜20 parts per million (ppm). For our detrended light curves, the best 6.5 h precision achieved is ˜15 ppm. We show that our detrended light curves have fewer systematic effects (or trends, or red-noise) than light curves produced by other groups from the same observations. Example light curves of transiting planets and a Cepheid variable candidate, are also presented. We make all light curves public, including the raw and detrended photometry, at http://k2.hatsurveys.org.

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

    NASA Technical Reports Server (NTRS)

    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.

  2. High Precision 2-D Grating Groove Density Measurement

    NASA Astrophysics Data System (ADS)

    Zhang, Ningxiao; McEntaffer, Randall; Tedesco, Ross

    2017-08-01

    Our research group at Penn State University is working on producing X-ray reflection gratings with high spectral resolving power and high diffraction efficiency. To estimate our fabrication accuracy, we apply a precise 2-D grating groove density measurement to plot groove density distributions of gratings on 6-inch wafers. In addition to plotting a fixed groove density distribution, this method is also sensitive to measuring the variation of the groove density simultaneously. This system can reach a measuring accuracy (ΔN/N) of 10-3. Here we present this groove density measurement and some applications.

  3. Calibrated infrared ground/air radiometric spectrometer

    NASA Astrophysics Data System (ADS)

    Silk, J. K.; Schildkraut, Elliot Robert; Bauldree, Russell S.; Goodrich, Shawn M.

    1996-06-01

    The calibrated infrared ground/air radiometric spectrometer (CIGARS) is a new high performance, multi-purpose, multi- platform Fourier transform spectrometer (FPS) sensor. It covers the waveband from 0.2 to 12 micrometer, has spectral resolution as fine as 0.3 cm-1, and records over 100 spectra per second. Two CIGARS units are being used for observations of target signatures in the air or on the ground from fixed or moving platforms, including high performance jet aircraft. In this paper we describe the characteristics and capabilities of the CIGARS sensor, which uses four interchangeable detector modules (Si, InGaAs, InSb, and HgCdTe) and two optics modules, with internal calibration. The data recording electronics support observations of transient events, even without precise information on the timing of the event. We present test and calibration data on the sensitivity, spectral resolution, stability, and spectral rate of CIGARS, and examples of in- flight observations of real targets. We also discuss plans for adapting CIGARS for imaging spectroscopy observations, with simultaneous spectral and spatial data, by replacing the existing detectors with a focal plane array (FPA).

  4. Key techniques of the high precision gravity field system

    NASA Astrophysics Data System (ADS)

    Xu, Weimin; Chen, Shi; Lu, Hongyan; Shi, Lei

    2017-04-01

    Ground-based gravity time series provide a direct method to monitor all sources of mass changes from local to global scale. But the effectively infinite spatial sensitivity of gravity measurements make it difficult to isolate the signal of interest. The high precision gravity field system is an alternative approach of modeling mass changes under-ground. The field system, consists of absolute gravity, gravity and gravity gradient, GNSS, leveling and climate hydrology measurements, can improve the signal-to-noise ratio for many applications by removing contributions of unwanted signal from elevation changes, air pressure changes, local hydrology, and others. The networks of field system combination, such as field-profile in more than 100 kilometers, can be used in critical zone with high seismic risk for monitoring earth dynamics, volcanic and seismic phenomena. The system is constituted by 9 typical observation stations in 3*3 array (or 4 in 2*2 array) in 60 square meters field, each station is designed for integrated measurements, including absolute gravity, gravity gradient, elevation changes, air pressure and hydrology. Time-lapse gravity changes resulting from absolute gravimeter (FG5 or A10) with standard deviation less than 2 μGal, without the contributions of Earth tides, loading and polar motion. Additional measurements such as air pressure change, local hydrology and soil moisture are indispensable. The elevation changes resulting from GNSS (on the base station) and leveling (between stations) with precision less than 10 mm. The gravity gradient is the significant measurement for delimiting the location of the related mass changes underground the station, which is measured by Scintrex CG-5 gravimeters in different height (80cm in the test field), with precision less than 10 E. It is necessary to improve the precision of gravity gradient measurements by certain method in field experiment for the high precision measurement system. Acknowledgment: This

  5. Thermal design and flight validation for high precision camera

    NASA Astrophysics Data System (ADS)

    Meng, Henghui; Sun, Lixia; Zhang, Chuanqiang; Geng, Liyin

    2015-10-01

    High precision camera, designed for advanced optical system, with a wide field of vision, high resolution and fast response, has a wild range of applications. As the main payload for spacecraft, the optical remote sensor is mounted exposed to the space, which means it should have a reliable optical performance in harsh space environment during lifetime. Because of the special optical characteristic, imaging path should be accurate, and less thermal deformation for the optical parts is required in the working process, so the high precision camera has a high level requirement for temperature. High resolution space camera is generally required to own the capability of adapting to space thermal environments. The flexible satellite's change of rolling attitude affects the temperature distribution of the camera and makes a difference to optical performance. The thermal control design of space camera is presented, and analysis the temperature data in orbit to prove the thermal design correct. It is proved that the rolling attitude has more influence on outer parts and less influence on inner parts, and active thermal control can weaken the influence of rolling attitude.

  6. High Precision U/Th Dating of First Polynesian Settlement

    PubMed Central

    Burley, David; Weisler, Marshall I.; Zhao, Jian-xin

    2012-01-01

    Previous studies document Nukuleka in the Kingdom of Tonga as a founder colony for first settlement of Polynesia by Lapita peoples. A limited number of radiocarbon dates are one line of evidence supporting this claim, but they cannot precisely establish when this event occurred, nor can they afford a detailed chronology for sequent occupation. High precision U/Th dates of Acropora coral files (abraders) from Nukuleka give unprecedented resolution, identifying the founder event by 2838±8 BP and documenting site development over the ensuing 250 years. The potential for dating error due to post depositional diagenetic alteration of ancient corals at Nukuleka also is addressed through sample preparation protocols and paired dates on spatially separated samples for individual specimens. Acropora coral files are widely distributed in Lapita sites across Oceania. U/Th dating of these artifacts provides unparalleled opportunities for greater precision and insight into the speed and timing of this final chapter in human settlement of the globe. PMID:23144962

  7. High-precision ground-based photometry of exoplanets

    NASA Astrophysics Data System (ADS)

    de Mooij, Ernst J. W.; Jayawardhana, Ray

    2013-04-01

    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.

  8. Describing oscillations of high energy neutrinos in matter precisely.

    PubMed

    Akhmedov, E K H; Maltoni, M; Smirnov, A Y U

    2005-11-18

    We present a formalism for precise description of oscillation phenomena in matter at high energies or high densities, V > Delta m(2)/2E, where V is the matter-induced potential of neutrinos. The accuracy of the approximation is determined by the quantity, where is the mixing angle in matter and is a typical change of the potential over the oscillation length (). We derive simple and physically transparent formulas for the oscillation probabilities, which are valid for arbitrary matter density profiles. They can be applied to oscillations of high-energy accelerator, atmospheric, and cosmic neutrinos in the matter of the Earth, substantially simplifying numerical calculations and providing an insight into the physics of neutrino oscillations in matter. The effect of parametric enhancement of the oscillations of high-energy neutrinos is considered.

  9. Radiometric sounding system

    SciTech Connect

    Whiteman, C.D.; Anderson, G.A.; Alzheimer, J.M.; Shaw, W.J.

    1995-04-01

    Vertical profiles of solar and terrestrial radiative fluxes are key research needs for global climate change research. These fluxes are expected to change as radiatively active trace gases are emitted to the earth`s atmosphere as a consequence of energy production and industrial and other human activities. Models suggest that changes in the concentration of such gases will lead to radiative flux divergences that will produce global warming of the earth`s atmosphere. Direct measurements of the vertical variation of solar and terrestrial radiative fluxes that lead to these flux divergences have been largely unavailable because of the expense of making such measurements from airplanes. These measurements are needed to improve existing atmospheric radiative transfer models, especially under the cloudy conditions where the models have not been adequately tested. A tethered-balloon-borne Radiometric Sounding System has been developed at Pacific Northwest Laboratory to provide an inexpensive means of making routine vertical soundings of radiative fluxes in the earth`s atmospheric boundary layer to altitudes up to 1500 m above ground level. Such vertical soundings would supplement measurements being made from aircraft and towers. The key technical challenge in the design of the Radiometric Sounding System is to develop a means of keeping the radiometers horizontal while the balloon ascends and descends in a turbulent atmospheric environment. This problem has been addressed by stabilizing a triangular radiometer-carrying platform that is carried on the tetherline of a balloon sounding system. The platform, carried 30 m or more below the balloon to reduce the balloon`s effect on the radiometric measurements, is leveled by two automatic control loops that activate motors, gears and pulleys when the platform is off-level. The sensitivity of the automatic control loops to oscillatory motions of various frequencies and amplitudes can be adjusted using filters.

  10. Precise measurement of magnetization characteristics in high pulsed field

    NASA Astrophysics Data System (ADS)

    Nakahata, Y.; Borkowski, B.; Shimoji, H.; Yamada, K.; Todaka, T.; Enokizono, M.

    2012-04-01

    Permanent magnets, especially Nd-Fe-B magnets, are very important engineering elements that are widely used in many applications. The detailed design of electrical and electronic equipment using permanent magnets requires the precise measurement of magnetization characteristics. High pulsed magnetic fields can be used to measure the magnetization characteristics of permanent magnets in the easy and hard magnetization directions. Errors influencing the measurements stem from the relationship between the tested material, pick-up sensor configuration, and excitation coil. We present an analysis of the effect of the sensor construction on the accuracy of the measurements of the material's magnetic properties. We investigated the coaxial and series types sensor configurations.

  11. High-precision measurements of global stellar magnetic fields

    NASA Astrophysics Data System (ADS)

    Plachinda, S. I.

    2014-06-01

    This paper presents a brief history of the development of devices and techniques for high-precision measurements of stellar magnetic fields. Two main approaches for the processing of spectral-polarimetric observations are described: the method of least-squares deconvolution (LSD), which is used to find a mean-weighted average of the normalized polarization profile using a set of spectral lines, and a method in which each individual spectral line is used to determine the magnetic field, viz., the single line method (SL). The advantages and disadvantages of the LSD and SL methods are discussed.

  12. High precision photon flux determination for photon tagging experiments

    SciTech Connect

    Teymurazyan, A.; Ahmidouch, A.; Ambrozewicz, P.; Asratyan, A.; Baker, K.; Benton, L.; Burkert, V.; Clinton, E.; Cole, P.; Collins, P.; Dale, D.; Danagoulian, S.; Davidenko, G.; Demirchyan, R.; Deur, A.; Dolgolenko, A.; Dzyubenko, G.; Ent, R.; Evdokimov, A.; Feng, J.; Gabrielyan, M.; Gan, L.; Gasparian, A.; Glamazdin, A.; Goryachev, V.; Hardy, K.; He, J.; Ito, M.; Jiang, L.; Kashy, D.; Khandaker, M.; Kolarkar, A.; Konchatnyi, M.; Korchin, A.; Korsch, W.; Kosinov, O.; Kowalski, S.; Kubantsev, M.; Kubarovsky, V.; Larin, I.; Lawrence, D.; Li, X.; Martel, P.; Matveev, V.; McNulty, D.; Mecking, B.; Milbrath, B.; Minehart, R.; Miskimen, R.; Mochalov, V.; Nakagawa, I.; Overby, S.; Pasyuk, E.; Payen, M.; Pedroni, R.; Prok, Y.; Ritchie, B.; Salgado, C.; Shahinyan, A.; Sitnikov, A.; Sober, D.; Stepanyan, S.; Stevens, W.; Underwood, J.; Vasiliev, A.; Vishnyakov, V.; Wood, M.; Zhou, S.

    2014-12-01

    The Jefferson Laboratory PrimEx Collaboration has developed and implemented a method to control the tagged photon flux in photoproduction experiments at the 1% level over the photon energy range from 4.9 to 5.5 GeV. This method has been successfully implemented in a high precision measurement of the neutral pion lifetime. Here, we outline the experimental equipment and the analysis techniques used to accomplish this. These include the use of a total absorption counter for absolute flux calibration, a pair spectrometer for online relative flux monitoring, and a new method for post-bremsstrahlung electron counting.

  13. Multidimensional Image Analysis for High Precision Radiation Therapy.

    PubMed

    Arimura, Hidetaka; Soufi, Mazen; Haekal, Mohammad

    2017-01-01

    High precision radiation therapy (HPRT) has been improved by utilizing conventional image engineering technologies. However, different frameworks are necessary for further improvement of HPRT. This review paper attempted to define the multidimensional image and what multidimensional image analysis is, which may be feasible for increasing the accuracy of HPRT. A number of researches in radiation therapy field have been introduced to understand the multidimensional image analysis. Multidimensional image analysis could greatly assist clinical staffs in radiation therapy planning, treatment, and prediction of treatment outcomes.

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

    SciTech Connect

    Luo, Mingxing

    1993-04-01

    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.

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

    SciTech Connect

    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.

  16. High-precision HST proper motions of globular clusters

    NASA Astrophysics Data System (ADS)

    Bellini, A.

    Photometric and spectroscopic studies over the last 15 years have revolutionized our understanding of globular clusters (GCs). We now know that essentially all GCs host multiple stellar populations that can be identified along all evolutionary sequences and are characterized by differences in light elements, He, and sometimes Fe. These findings present a number of formidable challenges for the study of the formation and evolution of GCs. The internal kinematics of multiple stellar populations is a fundamental piece of the puzzle and high-precision proper motions are the key tool to shed light on many open questions regarding GCs.

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

    DOEpatents

    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.

  18. High precision wavelength meter with Fabry-Perot optics

    NASA Astrophysics Data System (ADS)

    Konishi, N.; Suzuki, T.; Taira, Y.; Kato, H.; Kasuya, T.

    1981-07-01

    A high precision wavelength meter in the visible is described, which is based on a Fabry-Perot interferometer with several etalons of different resolution. The interference fringe pattern projected on a photo-diode array detector is computationally processed to give a stepwise refinement of the wavelength value to any adjusted accuracy. The present model intends to provide digital and real-time values of high precision wavelength for dye-laser spectroscopy, and to serve as a monitor or as a pilot for wavelength control of a dye-laser source of nanosecond pulses. The model is, therefore, designed with particular emphasis on its short-pulse capability and on-line mode of operation as well as on its high sensitivity and resolution. Some arrangements of essential necessity are involved therein, such as to avoid an errorneous wavelength readout for a noisy incidence of pulsed field. The ultimate accuracy of wavelength measurement is prescribed by the resolving power of the thickest etalon employed. As applied to the pulsed source, the model determines the wavelength to the accuracy of ±one part in 107 for even a single shot nanosecond incidence of a fraction of μJ energy. The design and performance are described in connection to pulsed dye-laser incidence.

  19. A High Precision Terahertz Wave Image Reconstruction Algorithm

    PubMed Central

    Guo, Qijia; Chang, Tianying; Geng, Guoshuai; Jia, Chengyan; Cui, Hong-Liang

    2016-01-01

    With the development of terahertz (THz) technology, the applications of this spectrum have become increasingly wide-ranging, in areas such as non-destructive testing, security applications and medical scanning, in which one of the most important methods is imaging. Unlike remote sensing applications, THz imaging features sources of array elements that are almost always supposed to be spherical wave radiators, including single antennae. As such, well-developed methodologies such as Range-Doppler Algorithm (RDA) are not directly applicable in such near-range situations. The Back Projection Algorithm (BPA) can provide products of high precision at the the cost of a high computational burden, while the Range Migration Algorithm (RMA) sacrifices the quality of images for efficiency. The Phase-shift Migration Algorithm (PMA) is a good alternative, the features of which combine both of the classical algorithms mentioned above. In this research, it is used for mechanical scanning, and is extended to array imaging for the first time. In addition, the performances of PMA are studied in detail in contrast to BPA and RMA. It is demonstrated in our simulations and experiments described herein that the algorithm can reconstruct images with high precision. PMID:27455269

  20. High-precision Photogrammetric Surface Figure Measurements under Cryogenic Environment

    NASA Astrophysics Data System (ADS)

    Zheng, Lou; Yuan, Qian; Sheng-hong, Fan; Chang-ru, Liu; Hai-ren, Wang; Ying-xi, Zuo; Jin-quan, Cheng; Ji, Yang

    2017-01-01

    Limited by the working temperature of the test equipment, most of high-precision surface figure measurement techniques cannot be put into application under a cryogenic environment. This paper reports the first attempt to measure the surface figure of a high-precision terahertz reflector panel under low temperatures based on photogrammetry. The measurement employs a high-resolution industrial camera sitting on the automatic testing platform which enables photos been taken in an automatic fashion inside a climate chamber. A repeatable accuracy of 2.1 μm (rms) is achieved under the cryogenic environment. Furthermore, the surface figure measured by a three-coordinate measuring machine under the room temperature is used to calibrate the thickness differences of the targets. By this technique, the surface figure of an aluminum prototype panel of the 5 meter Dome A Terahertz Telescope (DATE5) is measured from room temperature down to -55°C to obtain the rule of variation of surface deformation of the panel under low temperatures.

  1. The importance of high-precision hadronic calorimetry to physics

    NASA Astrophysics Data System (ADS)

    Hauptman, John

    2016-11-01

    The reconstruction and high-precision measurement of the four-vectors of W and Z decays to quarks, which constitute nearly 70% of their decay branching fractions, are critical to a high efficiency and high quality experiment. Furthermore, it is crucial that the energy resolution, and consequently the resolution on the invariant mass of the two fragmenting quarks, is comparable to the energy-momentum resolution on the other particles of the standard model, in particular, electrons, photons, and muons, at energies around 100 GeV. I show that this “unification of resolutions” on all particles of the standard model is now in sight, and will lead to excellent physics at an electron-positron collider.

  2. New machining method of high precision infrared window part

    NASA Astrophysics Data System (ADS)

    Yang, Haicheng; Su, Ying; Xu, Zengqi; Guo, Rui; Li, Wenting; Zhang, Feng; Liu, Xuanmin

    2016-10-01

    Most of the spherical shell of the photoelectric multifunctional instrument was designed as multi optical channel mode to adapt to the different band of the sensor, there were mainly TV, laser and infrared channels. Without affecting the optical diameter, wind resistance and pneumatic performance of the optical system, the overall layout of the spherical shell was optimized to save space and reduce weight. Most of the shape of the optical windows were special-shaped, each optical window directly participated in the high resolution imaging of the corresponding sensor system, and the optical axis parallelism of each sensor needed to meet the accuracy requirement of 0.05mrad.Therefore precision machining of optical window parts quality will directly affect the photoelectric system's pointing accuracy and interchangeability. Processing and testing of the TV and laser window had been very mature, while because of the special nature of the material, transparent and high refractive rate, infrared window parts had the problems of imaging quality and the control of the minimum focal length and second level parallel in the processing. Based on years of practical experience, this paper was focused on how to control the shape and parallel difference precision of infrared window parts in the processing. Single pass rate was increased from 40% to more than 95%, the processing efficiency was significantly enhanced, an effective solution to the bottleneck problem in the actual processing, which effectively solve the bottlenecks in research and production.

  3. High precision measurements of the free form mirror geometries

    NASA Astrophysics Data System (ADS)

    Dontsov, Denis; Rahneberg, Ilko; Pöschel, Wolfgang; Schott, Walter

    2017-06-01

    There are many established technologies for precise characterization of the mirror geometries available. The paper presents a high precision measuring setup based on a single beam homodyne laser interferometer. The single beam interferometer is moved by a linear stage between the reference and measuring surfaces and delivers the differences between them. The reference mirror defines an absolute accuracy of the method. This point based method allows a high spatial resolution of the mirror shape and is suitable for measurements of the free form mirror geometries as long as the radius of curvature does not exceed the maximal toleranced tilt. The measuring results have been obtained for optics with dimensions of up to 50 mm and have been verified both for plan mirrors and for mirrors with radii of curvature in the range between 6 m and 10 m. A repeatability of the measuring results in sub-nanometer range can be shown. Especially for mirrors with a very big radius of curvature the knowledge of the exact position of the each measuring point on the surface is important for minimizing the errors of the mathematical fitting algorithms. Therefore a triple beam interferometer has been used for measurements of the stage position. The tight synchronization between all interferometer channels of 0.1 ns allows very fast "on-the-fly" scans of the surface.

  4. High Precision Oxygen Measurements as a Tool for CCS Monitoring

    NASA Astrophysics Data System (ADS)

    Trugman, A. T.; Dvonch, C.; Clegg, S. M.; Rahn, T.

    2011-12-01

    CO2 emissions from below ground carbon storage reservoirs can be difficult to discriminate from CO2 produced via natural plant and microbial respiration. However, because respiration produces CO2 and consumes O2 in an approximately 1:1 ratio, it is possible to characterize leakage sources by measurement of simultaneous changes of both O2 and CO2. This approach is complicated by the fact that O2 comprises approximately 21% of the atmosphere, while CO2 is only present in the background atmosphere at ~400 parts per million, making it necessary to accurately measure changes in O2 concentration to six significant figures. Here we describe a portable high precision oxygen measurement system that employs a modified commercial fuel cell analyzer to quantify small changes in O2 concentration. High precision is achieved through precise control of flow and pressure, allowing near part per million precision of O2 and CO2 concentrations. This system has been incorporated into a mobile laboratory and has been deployed to the ZERT controlled release site in Bozeman, Montana and to a natural analog CO2 leak at Soda Springs, Idaho. Samples were collected at ground level, 1 meter, and 3 meters above the CO2 source and are displayed as the ratio of the O2 difference relative to a reference to the CO2 difference in concentration relative to the same reference (ΔO2/ΔCO2). It was observed that at wind speeds ≤ 2 m/s, the ΔO2/ΔCO2 anomaly decreased with height and was still significantly different from background at 3 m. With increasing wind speed, ΔO2/ΔCO2 anomalies decreased to background levels at 1 and 3 m but remained detectable at the ground surface. We will discuss attempts to quantify the CO2 release rate utilizing the measured ΔO2/ΔCO2 elevation profiles and will present complementary eddy covariance data for comparison.

  5. [VMTBB-Based Spectral Radiometric Calibration of NIR Fiber Coupled Spectrometer].

    PubMed

    Zheng, Feng; Liu, Li-ying; Liu, Xiao-xi; Li, Ye; Shi, Xiao-guang; Zhang, Guo-yu; Huan, Ke-wei

    2015-09-01

    The medium temperature black body (MTBB) is conventional high precision equipment used as spectral radiometric scale in infrared spectral region. However, in near-infrared (NIR) spectral region, there are few papers about spectral radiometric calibration by using MTBB, that is because NIR spectral region is the borderland of its effective spectral region. The main research of this paper is spectral radiometric calibration method by using MTBB in NIR spectral region. Accordingly, this paper is devoted mostly to a discussion of how the calibration precision could be affected by selecting different structural parameters of calibration model. The purpose of this paper is to present the results of research and provide technical reference for improving the traceability in NIR spectral radiometric calibration. In this paper, a NIR fiber coupled spectrometer, whose wavelength range covers from 950 to 1700 nm, has been calibrated by a MTBB with adjustable temperature range from 50 to 1050 °C. Concentrating on calibration process, two key points have been discussed. For one thing, the geometric factors of radiation transfer model of the calibration systems have been compared between traditional structure and fiber direct-coupled structure. Because the fiber direct-coupled model is simple and effective, it has been selected instead of traditional model based on the radiation transfer between two coaxial discs. So, it is an advantaged radiation transfer model for radiometric calibration of fiber coupled spectrometer. For another thing, the relation between calibration accuracy and structural parameters of calibration model has been analyzed intensively. The root cause is scale feature of attribute of calibration data itself, which is the nonlinear structure in scales of spectral data. So, the high precision calibration needs nonlinear calibration model, and the uniform sampling for scale feature is also very important. Selecting sample is an inevitable problem when the

  6. The development of high precision carbon fiber composite mirror

    NASA Astrophysics Data System (ADS)

    Xu, Liang; Ding, Jiao-teng; Wang, Yong-jie; Xie, Yong-jie; Ma, Zhen; Fan, Xue-wu

    2016-10-01

    Due to low density, high stiffness, low thermal expansion coefficient, duplicate molding, etc., carbon fiber reinforced polymer (CFRP) is one of the potential materials of the optical mirror. The process developed for Φ300mm high precision CFRP mirror described in this paper. A placement tool used to improve laying accuracy up to ± 0.1°.A special reinforced cell structure designed to increase rigidity and thermal stability. Optical replication process adopted for surface modification of the carbon fiber composite mirror blank. Finally, surface accuracy RMS of Φ300mm CFRP mirror is 0.22μm, surface roughness Ra is about 2nm, and the thermal stability can achieve 13nm /°C from the test result. The research content is of some reference value in the infrared as well as visible light applications.

  7. High Precision Assembly Line Synthesis for Molecules with Tailored Shapes

    PubMed Central

    Burns, Matthew; Essafi, Stephanie; Bame, Jessica R.; Bull, Stephanie P.; Webster, Matthew P.; Balieu, Sebastien; Dale, James W.; Butts, Craig P.; Harvey, Jeremy N.; Aggarwal, Varinder K.

    2014-01-01

    Molecular assembly lines, where molecules undergo iterative processes involving chain elongation and functional group manipulation are hallmarks of many processes found in Nature. We have sought to emulate Nature in the development of our own molecular assembly line through iterative homologations of boronic esters. Here we report a reagent (α-lithioethyl triispopropylbenzoate) which inserts into carbon-boron bonds with exceptionally high fidelity and stereocontrol. Through repeated iteration we have converted a simple boronic ester into a complex molecule (a carbon chain with ten contiguous methyl groups) with remarkably high precision over its length, its stereochemistry and therefore its shape. Different stereoisomers were targeted and it was found that they adopted different shapes (helical/linear) according to their stereochemistry. This work should now enable scientists to rationally design and create molecules with predictable shape, which could have an impact in all areas of molecular sciences where bespoke molecules are required. PMID:25209797

  8. High precision variational calculations of few-electron atoms

    NASA Astrophysics Data System (ADS)

    Bubin, Sergiy

    2015-05-01

    High precision calculations of energy levels and other properties of small atoms and ions have been a subject of fruitful interplay between the experiment and theory. However, most calculation of spectroscopic accuracy, until recently, have been possible only for two- and three-electron systems. In this talk I will report on progress toward performing high accuracy calculations of larger atomic systems (up to four-six electrons). The results of benchmark quality are attainable with the use of variational expansions in terms of all-particle explicitly correlated Gaussians, whose nonlinear variational parameters are extensively optimized. I will demonstrate what level of accuracy is available today for few-electron atoms and discuss the issues that must be overcome in order to extend the capability of the method to even larger systems. This work has been supported by the Ministry of Education and Science of Kazakhstan.

  9. High-precision analysis of the solar twin HIP 100963

    NASA Astrophysics Data System (ADS)

    Yana Galarza, Jhon; Meléndez, Jorge; Ramírez, Ivan; Yong, David; Karakas, Amanda I.; Asplund, Martin; Liu, Fan

    2016-05-01

    Context. HIP 100963 was one of the first solar twins identified. Although some high-precision analyses are available, a comprehensive high-precision study of chemical elements from different nucleosynthetic sources is still lacking from which to obtain potential new insights on planets, stellar evolution, and Galactic chemical evolution (GCE). Aims: We analyze and investigate the origin of the abundance pattern of HIP 100963 in detail, in particular the pattern of the light element Li, the volatile and refractory elements, and heavy elements from the s- and r-processes. Methods: We used the HIRES spectrograph on the Keck I telescope to acquire high-resolution (R ≈ 70 000) spectra with a high signal-to-noise ratio (S/N ≈ 400-650 per pixel) of HIP 100963 and the Sun for a differential abundance analysis. We measured the equivalent widths (EWs) of iron lines to determine the stellar parameters by employing the differential spectroscopic equilibrium. We determined the composition of volatile, refractory, and neutron-capture elements through a differential abundance analysis with respect to the Sun. Results: The stellar parameters we found are Teff = 5818 ± 4 K, log g = 4.49 ± 0.01 dex, vt = 1.03 ± 0.01km s-1, and [Fe/H] = -0.003 ± 0.004 dex. These low errors allow us to compute a precise mass (1.03+0.02-0.01 M⊙) and age (2.0 ± 0.4 Gyr), obtained using Yonsei-Yale isochrones. Using our [Y/Mg] ratio, we have determined an age of 2.1 ± 0.4 Gyr, in agreement with the age computed using isochrones. Our isochronal age also agrees with the age determined from stellar activity (2.4 ± 0.3 Gyr). We study the abundance pattern with condensation temperature (Tcond) taking corrections by the GCE into account. We show that the enhancements of neutron-capture elements are explained by contributions from both the s- and r-process. The lithium abundance follows the tight Li-age correlation seen in other solar twins. Conclusions: We confirm that HIP 100963 is a solar twin

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

    SciTech Connect

    Markus, Charles R.; Hodges, James N.; Perry, Adam J.; Kocheril, G. Stephen; McCall, Benjamin J.; Müller, Holger S. P.

    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.

  11. High precision optomechanical assembly using threads as mechanical reference

    NASA Astrophysics Data System (ADS)

    Lamontagne, Frédéric; Desnoyers, Nichola; Bergeron, Guy; Cantin, Mario

    2016-09-01

    A convenient method to assemble optomechanical components is to use threaded interface. For example, lenses are often secured inside barrels using threaded rings. In other cases, multiple optical sub-assemblies such as lens barrels can be threaded to each other. Threads have the advantage to provide a simple assembly method, to be easy to manufacture, and to offer a compact mechanical design. On the other hand, threads are not considered to provide accurate centering between parts because of the assembly clearance between the inner and outer threads. For that reason, threads are often used in conjunction with precision cylindrical surfaces to limit the radial clearance between the parts to be centered. Therefore, tight manufacturing tolerances are needed on these pilot diameters, which affect the cost of the optical assembly. This paper presents a new optomechanical approach that uses threads as mechanical reference. This innovative method relies on geometric principles to auto-center parts to each other with a very low centering error that is usually less than 5 μm. The method allows to auto-center an optical group in a main barrel, to perform an axial adjustment of an optical group inside a main barrel, and to perform stacking of multiple barrels. In conjunction with the lens auto-centering method that also used threads as a mechanical reference, this novel solution opens new possibilities to realize a variety of different high precision optomechanical assemblies at lower cost.

  12. Developing and implementing a high precision setup system

    NASA Astrophysics Data System (ADS)

    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

  13. Precision judgment criteria and supplement data processing method in high-precision ranging with dual-comb lasers

    NASA Astrophysics Data System (ADS)

    Zhou, Qian; Li, Yang; Ni, Kai; Xu, Mingfei; Dong, Hao; Wu, Guanhao

    2014-11-01

    A method using a pair of femtosecond frequency combs can realize ranging at a high precision of 1μm by Fourier Processing. In simulation of this system based on Matlab/Simulink, it is found that the choosing of repeating frequencies has great impact on frequency of the sampled signals, which influences the ranging precision a lot. The sampled signals are analyzed and classified into three types, which can be judgment criteria in system setting. Filter at Nyquist frequency is advised to decrease the edge effect of FFT, and a supplement means of cutting in data processing is proposed to improve precision.

  14. Simultaneous Precision Gravimetry and Magnetic Gradiometry with a Bose-Einstein Condensate: A High Precision, Quantum Sensor

    NASA Astrophysics Data System (ADS)

    Hardman, K. S.; Everitt, P. J.; McDonald, G. D.; Manju, P.; Wigley, P. B.; Sooriyabandara, M. A.; Kuhn, C. C. N.; Debs, J. E.; Close, J. D.; Robins, N. P.

    2016-09-01

    A Bose-Einstein condensate is used as an atomic source for a high precision sensor. A 5 ×1 06 atom F =1 spinor condensate of 87Rb is released into free fall for up to 750 ms and probed with a T =130 ms Mach-Zehnder atom interferometer based on Bragg transitions. The Bragg interferometer simultaneously addresses the three magnetic states |mf=1 ,0 ,-1 ⟩, facilitating a simultaneous measurement of the acceleration due to gravity with a 1000 run precision of Δ g /g =1.45 ×10-9 and the magnetic field gradient to a precision of 120 pT /m .

  15. IRCM spectral signature measurements instrumentation featuring enhanced radiometric accuracy

    NASA Astrophysics Data System (ADS)

    Lantagne, Stéphane; Prel, Florent; Moreau, Louis; Roy, Claude; Willers, Cornelius J.

    2015-10-01

    Hyperspectral Infrared (IR) signature measurements are performed in military applications including aircraft- and -naval vessel stealth characterization, detection/lock-on ranges, and flares efficiency characterization. Numerous military applications require high precision measurement of infrared signature characterization. For instance, Infrared Countermeasure (IRCM) systems and Infrared Counter-Countermeasure (IRCCM) system are continuously evolving. Infrared flares defeated IR guided seekers, IR flares became defeated by intelligent IR guided seekers and Jammers defeated the intelligent IR guided seekers [7]. A precise knowledge of the target infrared signature phenomenology is crucial for the development and improvement of countermeasure and counter-countermeasure systems and so precise quantification of the infrared energy emitted from the targets requires accurate spectral signature measurements. Errors in infrared characterization measurements can lead to weakness in the safety of the countermeasure system and errors in the determination of detection/lock-on range of an aircraft. The infrared signatures are analyzed, modeled, and simulated to provide a good understanding of the signature phenomenology to improve the IRCM and IRCCM technologies efficiency [7,8,9]. There is a growing need for infrared spectral signature measurement technology in order to further improve and validate infrared-based models and simulations. The addition of imagery to Spectroradiometers is improving the measurement capability of complex targets and scenes because all elements in the scene can now be measured simultaneously. However, the limited dynamic range of the Focal Plane Array (FPA) sensors used in these instruments confines the ranges of measurable radiance intensities. This ultimately affects the radiometric accuracy of these complex signatures. We will describe and demonstrate how the ABB hyperspectral imaging spectroradiometer features enhanced the radiometric accuracy

  16. Based on Narcissus of radiometric calibration technology

    NASA Astrophysics Data System (ADS)

    Jin, Libing; Tang, Shaofan; Liu, Jianfeng; Peng, Honggang

    2015-08-01

    Thermal radiation is an inherent property of all objects. Generally, it is believed that the body, which temperature is above absolute zero, can keep generating infrared radiation. Infrared remote sensing, using of satellite-borne or airborne sensors, collects infrared information to identify the surface feature and inversion of surface parameters, temperature, etc. In order to get more accurately feature information, quantitative measurement is required. Infrared radiometric calibration is one of the key technologies of quantitative infrared remote sensing. Most high-resolution thermal imaging systems are cooling. For the infrared optical system which is having a cooled detector, there are some special phenomenons. Since the temperature of the detector's photosensitive surface is generally low, which is very different from system temperature, it is a very strong cold radiation source. Narcissus refers to the case that the cooled detector can "see" its own reflecting image, which may affect the image quality of infrared system seriously. But for radiometric calibration of satellite-borne infrared camera, it can sometimes take advantage of the narcissus instead of cold cryogenic radiometric calibration. In this paper, the use of narcissus to carry out radiometric calibration is summarized, and simulation results show the feasibility.

  17. Monolithic interferometer for high precision radial velocity measurements

    NASA Astrophysics Data System (ADS)

    Wan, Xiaoke; Ge, Jian; Wang, Ji; Lee, Brian

    2009-08-01

    In high precision radial velocity (RV) measurements for extrasolar planets searching and studies, a stable wide field Michelson interferometer is very critical in Exoplanet Tracker (ET) instruments. Adopting a new design, monolithic interferometers are homogenous and continuous in thermal expansion, and field compensation and thermal compensation are both satisfied. Interferometer design and fabrication are decrypted in details. In performance evaluations, field angle is typically 22° and thermal sensitivity is typically -1.7 x 10-6/°C, which corresponds to ~500 m/s /°C in RV scale. In interferometer stability monitoring using a wavelength stabilized laser source, phase shift data was continuously recorded for nearly seven days. Appling a frequent calibration every 30 minutes as in typical star observations, the interferometer instability contributes less than 1.4 m/s in RV error, in a conservative estimation.

  18. Superconducting Tunnel Junctions for High-Precision EUV Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ponce, F.; Carpenter, M. H.; Cantor, R.; Friedrich, S.

    2016-08-01

    We have characterized the photon response of superconducting tunnel junctions in the extreme ultraviolet energy range below 100 eV with a pulsed 355 nm laser. The detectors are operated at rates up to 5000 counts/s, are very linear in energy and have an energy resolution between 0.9 and 2 eV. We observe multiple peaks that correspond to an integer number of photons with a Poissonian probability distribution and that can be used for high-accuracy energy calibration. The uncertainty of the centroid depends on the detector resolution and the counting statistics and can be as low as 1 meV for well-separated peaks with >10^5 counts. We discuss the precision of the peak centroid as a function of detector resolution and total number of counts and the accuracy of the energy calibration.

  19. Thermal-mechanical behavior of high precision composite mirrors

    NASA Astrophysics Data System (ADS)

    Kuo, C. P.; Lou, M. C.; Rapp, D.

    1993-04-01

    Composite mirror panels were designed, constructed, analyzed, and tested in the framework of a NASA precision segmented reflector task. The deformations of the reflector surface during the exposure to space enviroments were predicted using a finite element model. The composite mirror panels have graphite-epoxy or graphite-cyanate facesheets, separated by an aluminum or a composite honeycomb core. It is pointed out that in order to carry out detailed modeling of composite mirrors with high accuracy, it is necessary to have temperature dependent properties of the materials involved and the type and magnitude of manufacturing errors and material nonuniformities. The structural modeling and analysis efforts addressed the impact of key design and materials parameters on the performance of mirrors.

  20. A high precision semi-analytic mass function

    NASA Astrophysics Data System (ADS)

    Del Popolo, Antonino; Pace, Francesco; Le Delliou, Morgan

    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 Mvir = 5 × 109 h‑1Msolar–‑5 × 1014 h‑1Msolar and redshift range 0 lesssim z lesssim 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 1012–1016 h‑1Msolar. Moreover, we discuss our MF validity for different cosmologies.

  1. Precision Viticulture from Multitemporal, Multispectral Very High Resolution Satellite Data

    NASA Astrophysics Data System (ADS)

    Kandylakis, Z.; Karantzalos, K.

    2016-06-01

    In order to exploit efficiently very high resolution satellite multispectral data for precision agriculture applications, validated methodologies should be established which link the observed reflectance spectra with certain crop/plant/fruit biophysical and biochemical quality parameters. To this end, based on concurrent satellite and field campaigns during the veraison period, satellite and in-situ data were collected, along with several grape samples, at specific locations during the harvesting period. These data were collected for a period of three years in two viticultural areas in Northern Greece. After the required data pre-processing, canopy reflectance observations, through the combination of several vegetation indices were correlated with the quantitative results from the grape/must analysis of grape sampling. Results appear quite promising, indicating that certain key quality parameters (like brix levels, total phenolic content, brix to total acidity, anthocyanin levels) which describe the oenological potential, phenolic composition and chromatic characteristics can be efficiently estimated from the satellite data.

  2. A detector interferometric calibration experiment for high precision astrometry

    NASA Astrophysics Data System (ADS)

    Crouzier, A.; Malbet, F.; Henault, F.; Léger, A.; Cara, C.; LeDuigou, J. M.; Preis, O.; Kern, P.; Delboulbe, A.; Martin, G.; Feautrier, P.; Stadler, E.; Lafrasse, S.; Rochat, S.; Ketchazo, C.; Donati, M.; Doumayrou, E.; Lagage, P. O.; Shao, M.; Goullioud, R.; Nemati, B.; Zhai, C.; Behar, E.; Potin, S.; Saint-Pe, M.; Dupont, J.

    2016-11-01

    Context. Exoplanet science has made staggering progress in the last two decades, due to the relentless exploration of new detection methods and refinement of existing ones. Yet astrometry offers a unique and untapped potential of discovery of habitable-zone low-mass planets around all the solar-like stars of the solar neighborhood. To fulfill this goal, astrometry must be paired with high precision calibration of the detector. Aims: We present a way to calibrate a detector for high accuracy astrometry. An experimental testbed combining an astrometric simulator and an interferometric calibration system is used to validate both the hardware needed for the calibration and the signal processing methods. The objective is an accuracy of 5 × 10-6 pixel on the location of a Nyquist sampled polychromatic point spread function. Methods: The interferometric calibration system produced modulated Young fringes on the detector. The Young fringes were parametrized as products of time and space dependent functions, based on various pixel parameters. The minimization of function parameters was done iteratively, until convergence was obtained, revealing the pixel information needed for the calibration of astrometric measurements. Results: The calibration system yielded the pixel positions to an accuracy estimated at 4 × 10-4 pixel. After including the pixel position information, an astrometric accuracy of 6 × 10-5 pixel was obtained, for a PSF motion over more than five pixels. In the static mode (small jitter motion of less than 1 × 10-3 pixel), a photon noise limited precision of 3 × 10-5 pixel was reached.

  3. MultiView High Precision VLBI Astrometry at Low Frequencies

    NASA Astrophysics Data System (ADS)

    Rioja, María J.; Dodson, Richard; Orosz, Gabor; Imai, Hiroshi; Frey, Sandor

    2017-03-01

    The arrival of the Square Kilometer Array (SKA) will revitalize all aspects of Very Long Baseline Interferometry (VLBI) astronomy at lower frequencies. In the last decade, there have been huge strides toward routinely achieving high precision VLBI astrometry at frequencies dominated by tropospheric contributions, most notably at 22 GHz, using advanced phase-referencing techniques. Nevertheless, to increase the capability for high precision astrometric measurements at low radio frequencies (<8 GHz), an effective calibration strategy of the systematic ionospheric propagation effects that is widely applicable is required. Observations at low frequencies are dominated by distinct direction-dependent ionospheric propagation errors, which place a very tight limit on the angular separation of a suitable phase-referencing calibrator. The MultiView technique holds the key to compensating for atmospheric spatial-structure errors, by using observations of multiple calibrators and two-dimensional interpolation in the visibility domain. In this paper we present the first demonstration of the power of MultiView using three calibrators, several degrees from the target, along with a comparative study of the astrometric accuracy between MultiView and phase-referencing techniques. MultiView calibration provides an order of magnitude improvement in astrometry with respect to conventional phase referencing, achieving ∼100 μas astrometry errors in a single epoch of observations, effectively reaching the thermal noise limit. MultiView will achieve its full potential with the enhanced sensitivity and multibeam capabilities of SKA and the pathfinders, which will enable simultaneous observations of the target and calibrators. Our demonstration indicates that the 10 μas goal of astrometry at ∼1.6 GHz using VLBI with SKA is feasible using the MultiView technique.

  4. Describing Oscillations of High Energy Neutrinos in Matter Precisely

    SciTech Connect

    Akhmedov, E.Kh.; Maltoni, M.; Smirnov, A.Yu.

    2005-11-18

    We present a formalism for precise description of oscillation phenomena in matter at high energies or high densities, V>{delta}m{sup 2}/2E, where V is the matter-induced potential of neutrinos. The accuracy of the approximation is determined by the quantity sin{sup 2}2{theta}{sub m}{delta}V/2{pi}V, where {theta}{sub m} is the mixing angle in matter and {delta}V is a typical change of the potential over the oscillation length (l{approx}2{pi}/V). We derive simple and physically transparent formulas for the oscillation probabilities, which are valid for arbitrary matter density profiles. They can be applied to oscillations of high-energy (E>10 GeV) accelerator, atmospheric, and cosmic neutrinos in the matter of the Earth, substantially simplifying numerical calculations and providing an insight into the physics of neutrino oscillations in matter. The effect of parametric enhancement of the oscillations of high-energy neutrinos is considered.

  5. Precision muon tracking detectors for high-energy hadron colliders

    NASA Astrophysics Data System (ADS)

    Gadow, Ph.; Kortner, O.; Kroha, H.; Richter, R.

    2017-02-01

    Small-diameter muon drift tube (sMDT) chambers with 15 mm tube diameter are a cost-effective technology for high-precision muon tracking over large areas at high background rates as expected at future high-energy hadron colliders including HL-LHC. The chamber design and construction procedures have been optimised for mass production and provide sense wire positioning accuracy of better than 10 μm. The rate capability of the sMDT chambers has been extensively tested at the CERN Gamma Irradiation Facility. It exceeds the one of the ATLAS muon drift tube (MDT) chambers, which are operated at unprecedentedly high background rates of neutrons and γ-rays, by an order of magnitude, which is sufficient for almost the whole of the muon detector acceptance at FCC-hh at maximum luminosity. sMDT operational and construction experience exists from ATLAS muon spectrometer upgrades which are in progress or under preparation for LHC Phase 1 and 2.

  6. Fast, High-Precision Readout Circuit for Detector Arrays

    NASA Technical Reports Server (NTRS)

    Rider, David M.; Hancock, Bruce R.; Key, Richard W.; Cunningham, Thomas J.; Wrigley, Chris J.; Seshadri, Suresh; Sander, Stanley P.; Blavier, Jean-Francois L.

    2013-01-01

    The GEO-CAPE mission described in NASA's Earth Science and Applications Decadal Survey requires high spatial, temporal, and spectral resolution measurements to monitor and characterize the rapidly changing chemistry of the troposphere over North and South Americas. High-frame-rate focal plane arrays (FPAs) with many pixels are needed to enable such measurements. A high-throughput digital detector readout integrated circuit (ROIC) that meets the GEO-CAPE FPA needs has been developed, fabricated, and tested. The ROIC is based on an innovative charge integrating, fast, high-precision analog-to-digital circuit that is built into each pixel. The 128×128-pixel ROIC digitizes all 16,384 pixels simultaneously at frame rates up to 16 kHz to provide a completely digital output on a single integrated circuit at an unprecedented rate of 262 million pixels per second. The approach eliminates the need for off focal plane electronics, greatly reducing volume, mass, and power compared to conventional FPA implementations. A focal plane based on this ROIC will require less than 2 W of power on a 1×1-cm integrated circuit. The ROIC is fabricated of silicon using CMOS technology. It is designed to be indium bump bonded to a variety of detector materials including silicon PIN diodes, indium antimonide (InSb), indium gallium arsenide (In- GaAs), and mercury cadmium telluride (HgCdTe) detector arrays to provide coverage over a broad spectral range in the infrared, visible, and ultraviolet spectral ranges.

  7. Precision, high dose radiotherapy: helium ion treatment of uveal melanoma

    SciTech Connect

    Saunders, W.M.; Char, D.H.; Quivey, J.M.; Castro, J.R.; Chen, G.T.Y.; Collier, J.M.; Cartigny, A.; Blakely, E.A.; Lyman, J.T.; Zink, S.R.

    1985-02-01

    The authors report on 75 patients with uveal melanoma who were treated by placing the Bragg peak of a helium ion beam over the tumor volume. The technique localizes the high dose region very tightly around the tumor volume. This allows critical structures, such as the optic disc and the macula, to be excluded from the high dose region as long as they are 3 to 4 mm away from the edge of the tumor. Careful attention to tumor localization, treatment planning, patient immobilization and treatment verification is required. With a mean follow-up of 22 months (3 to 60 months) the authors have had only five patients with a local recurrence, all of whom were salvaged with another treatment. Pretreatment visual acuity has generally been preserved as long as the tumor edge is at least 4 mm away from the macula and optic disc. The only serious complication to date has been an 18% incidence of neovascular glaucoma in the patients treated at our highest dose level. Clinical results and details of the technique are presented to illustrate potential clinical precision in administering high dose radiotherapy with charged particles such as helium ions or protons.

  8. Evaluation of High-Precision Sensors in Structural Monitoring

    PubMed Central

    Erol, Bihter

    2010-01-01

    One of the most intricate branches of metrology involves the monitoring of displacements and deformations of natural and anthropogenic structures under environmental forces, such as tidal or tectonic phenomena, or ground water level changes. Technological progress has changed the measurement process, and steadily increasing accuracy requirements have led to the continued development of new measuring instruments. The adoption of an appropriate measurement strategy, with proper instruments suited for the characteristics of the observed structure and its environmental conditions, is of high priority in the planning of deformation monitoring processes. This paper describes the use of precise digital inclination sensors in continuous monitoring of structural deformations. The topic is treated from two viewpoints: (i) evaluation of the performance of inclination sensors by comparing them to static and continuous GPS observations in deformation monitoring and (ii) providing a strategy for analyzing the structural deformations. The movements of two case study objects, a tall building and a geodetic monument in Istanbul, were separately monitored using dual-axes micro-radian precision inclination sensors (inclinometers) and GPS. The time series of continuous deformation observations were analyzed using the Least Squares Spectral Analysis Technique (LSSA). Overall, the inclinometers showed good performance for continuous monitoring of structural displacements, even at the sub-millimeter level. Static GPS observations remained insufficient for resolving the deformations to the sub-centimeter level due to the errors that affect GPS signals. With the accuracy advantage of inclination sensors, their use with GPS provides more detailed investigation of deformation phenomena. Using inclinometers and GPS is helpful to be able to identify the components of structural responses to the natural forces as static, quasi-static, or resonant. PMID:22163499

  9. Evaluation of high-precision sensors in structural monitoring.

    PubMed

    Erol, Bihter

    2010-01-01

    One of the most intricate branches of metrology involves the monitoring of displacements and deformations of natural and anthropogenic structures under environmental forces, such as tidal or tectonic phenomena, or ground water level changes. Technological progress has changed the measurement process, and steadily increasing accuracy requirements have led to the continued development of new measuring instruments. The adoption of an appropriate measurement strategy, with proper instruments suited for the characteristics of the observed structure and its environmental conditions, is of high priority in the planning of deformation monitoring processes. This paper describes the use of precise digital inclination sensors in continuous monitoring of structural deformations. The topic is treated from two viewpoints: (i) evaluation of the performance of inclination sensors by comparing them to static and continuous GPS observations in deformation monitoring and (ii) providing a strategy for analyzing the structural deformations. The movements of two case study objects, a tall building and a geodetic monument in Istanbul, were separately monitored using dual-axes micro-radian precision inclination sensors (inclinometers) and GPS. The time series of continuous deformation observations were analyzed using the Least Squares Spectral Analysis Technique (LSSA). Overall, the inclinometers showed good performance for continuous monitoring of structural displacements, even at the sub-millimeter level. Static GPS observations remained insufficient for resolving the deformations to the sub-centimeter level due to the errors that affect GPS signals. With the accuracy advantage of inclination sensors, their use with GPS provides more detailed investigation of deformation phenomena. Using inclinometers and GPS is helpful to be able to identify the components of structural responses to the natural forces as static, quasi-static, or resonant.

  10. Developing Performance Estimates for High Precision Astrometry with TMT

    NASA Astrophysics Data System (ADS)

    Schoeck, Matthias; Do, Tuan; Ellerbroek, Brent; Herriot, Glen; Meyer, Leo; Suzuki, Ryuji; Wang, Lianqi; Yelda, Sylvana

    2013-12-01

    Adaptive optics on Extremely Large Telescopes will open up many new science cases or expand existing science into regimes unattainable with the current generation of telescopes. One example of this is high-precision astrometry, which has requirements in the range from 10 to 50 micro-arc-seconds for some instruments and science cases. Achieving these requirements imposes stringent constraints on the design of the entire observatory, but also on the calibration procedures, observing sequences and the data analysis techniques. This paper summarizes our efforts to develop a top down astrometry error budget for TMT. It is predominantly developed for the first-light AO system, NFIRAOS, and the IRIS instrument, but many terms are applicable to other configurations as well. Astrometry error sources are divided into 5 categories: Reference source and catalog errors, atmospheric refraction correction errors, other residual atmospheric effects, opto-mechanical errors and focal plane measurement errors. Results are developed in parametric form whenever possible. However, almost every error term in the error budget depends on the details of the astrometry observations, such as whether absolute or differential astrometry is the goal, whether one observes a sparse or crowded field, what the time scales of interest are, etc. Thus, it is not possible to develop a single error budget that applies to all science cases and separate budgets are developed and detailed for key astrometric observations. Our error budget is consistent with the requirements for differential astrometry of tens of micro-arc-seconds for certain science cases. While no show stoppers have been found, the work has resulted in several modifications to the NFIRAOS optical surface specifications and reference source design that will help improve the achievable astrometry precision even further.

  11. Highly precise and robust packaging of optical components

    NASA Astrophysics Data System (ADS)

    Leers, Michael; Winzen, Matthias; Liermann, Erik; Faidel, Heinrich; Westphalen, Thomas; Miesner, Jörn; Luttmann, Jörg; Hoffmann, Dieter

    2012-03-01

    In this paper we present the development of a compact, thermo-optically stable and vibration and mechanical shock resistant mounting technique by soldering of optical components. Based on this technique a new generation of laser sources for aerospace applications is designed. In these laser systems solder technique replaces the glued and bolted connections between optical component, mount and base plate. Alignment precision in the arc second range and realization of long term stability of every single part in the laser system is the main challenge. At the Fraunhofer Institute for Laser Technology ILT a soldering and mounting technique has been developed for high precision packaging. The specified environmental boundary conditions (e.g. a temperature range of -40 °C to +50 °C) and the required degrees of freedom for the alignment of the components have been taken into account for this technique. In general the advantage of soldering compared to gluing is that there is no outgassing. In addition no flux is needed in our special process. The joining process allows multiple alignments by remelting the solder. The alignment is done in the liquid phase of the solder by a 6 axis manipulator with a step width in the nm range and a tilt in the arc second range. In a next step the optical components have to pass the environmental tests. The total misalignment of the component to its adapter after the thermal cycle tests is less than 10 arc seconds. The mechanical stability tests regarding shear, vibration and shock behavior are well within the requirements.

  12. Automated geographic registration and radiometric correction for UAV-based mosaics

    NASA Astrophysics Data System (ADS)

    Thomasson, J. Alex; Shi, Yeyin; Sima, Chao; Yang, Chenghai; Cope, Dale A.

    2017-05-01

    Texas A and M University has been operating a large-scale, UAV-based, agricultural remote-sensing research project since 2015. To use UAV-based images in agricultural production, many high-resolution images must be mosaicked together to create an image of an agricultural field. Two key difficulties to science-based utilization of such mosaics are geographic registration and radiometric calibration. In our current research project, image files are taken to the computer laboratory after the flight, and semi-manual pre-processing is implemented on the raw image data, including ortho-mosaicking and radiometric calibration. Ground control points (GCPs) are critical for high-quality geographic registration of images during mosaicking. Applications requiring accurate reflectance data also require radiometric-calibration references so that reflectance values of image objects can be calculated. We have developed a method for automated geographic registration and radiometric correction with targets that are installed semi-permanently at distributed locations around fields. The targets are a combination of black (≍5% reflectance), dark gray (≍20% reflectance), and light gray (≍40% reflectance) sections that provide for a transformation of pixel-value to reflectance in the dynamic range of crop fields. The exact spectral reflectance of each target is known, having been measured with a spectrophotometer. At the time of installation, each target is measured for position with a real-time kinematic GPS receiver to give its precise latitude and longitude. Automated location of the reference targets in the images is required for precise, automated, geographic registration; and automated calculation of the digital-number to reflectance transformation is required for automated radiometric calibration. To validate the system for radiometric calibration, a calibrated UAV-based image mosaic of a field was compared to a calibrated single image from a manned aircraft. Reflectance

  13. High-precision efficiency calibration of a high-purity co-axial germanium detector

    NASA Astrophysics Data System (ADS)

    Blank, B.; Souin, J.; Ascher, P.; Audirac, L.; Canchel, G.; Gerbaux, M.; Grévy, S.; Giovinazzo, J.; Guérin, H.; Nieto, T. Kurtukian; Matea, I.; Bouzomita, H.; Delahaye, P.; Grinyer, G. F.; Thomas, J. C.

    2015-03-01

    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.

  14. A simple high-precision Jacob's staff design for the high-resolution stratigrapher

    USGS Publications Warehouse

    Elder, W.P.

    1989-01-01

    The new generation of high-resolution stratigraphic research depends upon detailed bed-by-bed analysis to enhance regional correlation potential. The standard Jacob's staff is not an efficient and precise tool for measuring thin-bedded strata. The high-precision Jacob's staff design presented and illustrated in this paper meets the qualifications required of such an instrument. The prototype of this simple design consists of a sliding bracket that holds a Brunton-type compass at right angles to a ruled-off staff. This instrument provides rapid and accurate measurement of both thick- or thin-bedded sequences, thus decreasing field time and increasing stratigraphic precision. -Author

  15. High-Precision Measurement of the Proton's Atomic Mass

    NASA Astrophysics Data System (ADS)

    Heiße, F.; Köhler-Langes, F.; Rau, S.; Hou, J.; Junck, S.; Kracke, A.; Mooser, A.; Quint, W.; Ulmer, S.; Werth, G.; Blaum, K.; Sturm, S.

    2017-07-01

    We report on the precise measurement of the atomic mass of a single proton with a purpose-built Penning-trap system. With a precision of 32 parts per trillion our result not only improves on the current CODATA literature value by a factor of 3, but also disagrees with it at a level of about 3 standard deviations.

  16. High-Precision Studies of Compact Variable Stars

    NASA Astrophysics Data System (ADS)

    Bloemen, Steven

    2014-10-01

    This book, which is a reworked and updated version of Steven Bloemen's original PhD thesis, reports on several high-precision studies of compact variable stars. Its strength lies in the large variety of observational, theoretical and instrumentation techniques that are presented and used and paves the way towards new and detailed asteroseismic applications of single and binary subdwarf stars. Close binary stars are studied using high cadence spectroscopic datasets collected with state of the art electron multiplying CCDs and analysed using Doppler tomography visualization techniques. The work touches upon instrumentation, presenting the calibration of a new fast, multi-colour camera installed at the Mercator Telescope on La Palma. The thesis also includes theoretical work on the computation of the temperature range in which stellar oscillations can be driven in subdwarf B-stars. Finally, the highlight of the thesis is the measurement of velocities of stars using only photometric data from NASA's Kepler satellite. Doppler beaming causes stars to appear slightly brighter when they move towards us in their orbits, and this subtle effect can be seen in Kepler's brightness measurements. The thesis presents the first validation of such velocity measurements using independent spectroscopic measurements. Since the detection and validation of this Doppler beaming effect, it has been used in tens of studies to detect and characterize binary star systems, which are key calibrators in stellar astronomy.

  17. High-precision heliostat for long-path light tracking

    NASA Astrophysics Data System (ADS)

    Hawat, Tom; Stephen, Thomas M.; DeMaziere, Martine M.; Neefs, Eddy

    2003-08-01

    A heliostat has been designed and built for use in optical remote sensing of the atmosphere. The heliostat uses two flat mirrors to track the sun and direct the sunlight to optical instruments. A stepper motor driven horizontal turntable is used to track the sun in azimuth and support an elevation assembly and a mechanical tower. The stepper motor driven elevation assembly drives an acquisition mirror that tracks the sun in elevation. This mirror directs the solar beam to a secondary mirror fixed on the mechanical tower. The secondary mirror then directs the solar beam along the axis of the tracker for use in measurements. A sensitive, high resolution CCD camera, receives a small part of the solar beam to analyze for fine servo-control. Ground based tests have demonstrated this instrument"s tracking capability for the sun, the moon, stars and for long pathlength sources. Presently, this system is coupled with a high-resolution Brucker 120M spectrometer used to obtain solar absorption spectra. The heliostat directs the solar radiation along the spectrometer optical axis. The pointing precision was measured to be better than 0.5 arcsec. A description of the heliostat is presented, as well as the results of ground tests.

  18. Intraband radiometric performance of the Landsat Thematic Mappers.

    USGS Publications Warehouse

    Kieffer, H.H.; Cook, D.A.; Eliason, E.M.; Eliason, P.T.

    1985-01-01

    Radiometric characteristics have been examined of the Landsat-4 and Landsat-5 Thematic Mappers (TMs) that can be established without absolute calibration of spectral data. This analysis is based on radiometrically and geometrically raw (B-type) data of both uniform (flat-field) and high-contrast scenes. Subscenes selected for uniform radiance were used to characterized subtle radiometric differences and noise problems. Although the general performance of the Thematic Mappers is excellent, various anomalies that have a magnitude of a few digital levels (DN) or less are quantified. -from Authors

  19. Laboratory Measurement of Bidirectional Reflectance of Radiometric Tarps

    NASA Technical Reports Server (NTRS)

    Knowlton, Kelly

    2006-01-01

    Objectives: a) To determine the magnitude of radiometric tarp BRDF; b) To determine whether an ASD FieldSpec Pro spectroradiometer can be used to perform the experiment. Radiometric tarps with nominal reflectance values of 52%, 35%, and 3.5%, deployed for IKONOS. QuickBird, and OrbView-3 overpasses Ground-based spectroradiometric measurements of tarp and Spectralon@ panel taken during overpass using ASD FieldSpec Pro spectroradiometer, and tarp reflectance calculated. Reflectance data used in atmospheric radiative transfer model (MODTRAN) to predict satellite at-sensor radiance for radiometric calibration. Reflectance data also used to validate atmospheric correction of high-spatial-resolution multispectral image products

  20. High-speed high-precision and ultralong-range complex spectral domain dimensional metrology.

    PubMed

    Bao, Wen; Shen, Yi; Chen, Tao; Li, Peng; Ding, Zhihua

    2015-05-04

    A precise, nondestructive dimensional metrological system is crucial to manufacturing and packaging of multi-component optical system. To this end, an orthogonal dispersive spectrometer based complex spectral domain interferometric system for high-speed high-precision and ultralong-range dimensional metrology is developed. An improved complex method based on actual spectral phase shift is proposed to achieve ultrahigh suppression of artifacts. Suppression ratios of 80 dB for DC and 60 dB for mirror images are realized, the highest ratios among existing complex methods. To ensure high-precision in distance determination, an averaged spectral phase measurement algorithm is adopted. A precision of 60 nm within a measurement range of 200 mm without axial movement of the sample is demonstrated. The measurement range is readily extendable if axial movement of the sample and range cascading are involved. The system holds potential applications in various areas for real-time nondestructive testing and evaluation.

  1. Precision cosmology with time delay lenses: high resolution imaging requirements

    SciTech Connect

    Meng, Xiao-Lei; Liao, Kai; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Marshall, Philip J. E-mail: tt@astro.ucla.edu E-mail: mauger@ast.cam.ac.uk E-mail: dr.phil.marshall@gmail.com

    2015-09-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ''Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρ{sub tot}∝ r{sup −γ'} for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. However, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will

  2. Precision cosmology with time delay lenses: High resolution imaging requirements

    SciTech Connect

    Meng, Xiao -Lei; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Liao, Kai; Marshall, Philip J.

    2015-09-28

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ``Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρtot∝ r–γ' for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. Furthermore, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will

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

    NASA Astrophysics Data System (ADS)

    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

  4. High-precision Mg isotopic systematics of bulk chondrites

    NASA Astrophysics Data System (ADS)

    Schiller, Martin; Handler, Monica R.; Baker, Joel A.

    2010-08-01

    Variations of the mass-independent abundance of 26Mg ( δ26Mg*) and stable Mg ( δ25Mg) isotope composition of chondrites are important because they constrain the homogeneity of 26Al and Mg isotopes in the proto-planetary disc and the validity of the short-lived 26Al-to- 26Mg chronometer applied to meteorites. We present high-precision Mg isotope data and Al/Mg ratios of chondrites representing nearly all major chondrite classes, including a step-leaching experiment on the CM2 chondrite Murchison. δ26Mg* variations in leachates of Murchison representing acid soluble material are ≤ 30 times smaller than reported for neutron-rich isotopes of Ti and Cr and do not reveal resolvable deficits in δ26Mg* (-0.002 to + 0.118‰). Very small variations in δ26Mg* anomalies in bulk chondrites (-0.006 to + 0.019‰) correlate with increasing 27Al/ 24Mg ratios and δ50Ti, reflecting the variable presence of calcium-aluminium-rich inclusions (CAIs) in some types of carbonaceous chondrites. Similarly, release of radiogenic 26Mg produced by 26Al decay from CAI material in the step-leaching of Murchison best explains the high δ26Mg* observed in the last, aggressive, leaching steps of this experiment. Overall, the observed variations in δ26Mg* are small and potential differences beyond that which result from the presence of CAI-like material cannot be detected within the analytical uncertainties of this study (± 0.004‰). The results do not allow radical heterogeneity of 26Al (≥±30%) or measurable Mg nucleosynthetic heterogeneity (≥±0.005‰) to have existed on a planetesimal scale in the proto-planetary disc. Combined with published δ26Mg* data for CAIs, the bulk chondrite data yield a precise initial ( 26Al/ 27Al) 0 = (5.21 ± 0.06) × 10 -5 and δ26Mg* = -0.0340 ± 0.0016‰ for the Solar System. However, it is not possible with the currently available data to determine with certainty whether CAIs and the material from which planetesimals accreted including

  5. High precision optical finishing of lightweight silicon carbide aspheric mirror

    NASA Astrophysics Data System (ADS)

    Kong, John; Young, Kevin

    2010-10-01

    Critical to the deployment of large surveillance optics into the space environment is the generation of high quality optics. Traditionally, aluminum, glass and beryllium have been used; however, silicon carbide becomes of increasing interest and availability due to its high strength. With the hardness of silicon carbide being similar to diamond, traditional polishing methods suffer from slow material removal rates, difficulty in achieving the desired figure and inherent risk of causing catastrophic damage to the lightweight structure. Rather than increasing structural capacity and mass of the substrate, our proprietary sub-aperture aspheric surface forming technology offers higher material removal rates (comparable to that of Zerodur or Fused Silica), a deterministic approach to achieving the desired figure while minimizing contact area and the resulting load on the optical structure. The technology performed on computer-controlled machines with motion control software providing precise and quick convergence of surface figure, as demonstrated by optically finishing lightweight silicon carbide aspheres. At the same time, it also offers the advantage of ideal pitch finish of low surface micro-roughness and low mid-spatial frequency error. This method provides a solution applicable to all common silicon carbide substrate materials, including substrates with CVD silicon carbide cladding, offered by major silicon carbide material suppliers. This paper discusses a demonstration mirror we polished using this novel technology. The mirror is a lightweight silicon carbide substrate with CVD silicon carbide cladding. It is a convex hyperbolic secondary mirror with 104mm diameter and approximately 20 microns aspheric departure from best-fit sphere. The mirror has been finished with surface irregularity of better than 1/50 wave RMS @632.8 nm and surface micro-roughness of under 2 angstroms RMS. The technology has the potential to be scaled up for manufacturing capabilities of

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

    PubMed

    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.

  7. Laser interferometric high-precision angle monitor for JASMINE

    NASA Astrophysics Data System (ADS)

    Niwa, Yoshito; Arai, Koji; Sakagami, Masaaki; Gouda, Naoteru; Kobayashi, Yukiyasu; Yamada, Yoshiyuki; Yano, Taihei

    2006-06-01

    The JASMINE instrument uses a beam combiner to observe two different fields of view separated by 99.5 degrees simultaneously. This angle is so-called basic angle. The basic angle of JASMINE should be stabilized and fluctuations of the basic angle should be monitored with the accuracy of 10 microarcsec in root-mean-square over the satellite revolution period of 5 hours. For this purpose, a high-precision interferometric laser metrogy system is employed. One of the available techniques for measuring the fluctuations of the basic angle is a method known as the wave front sensing using a Fabry-Perot type laser interferometer. This technique is to detect fluctuations of the basic angle as displacement of optical axis in the Fabry-Perot cavity. One of the advantages of the technique is that the sensor is made to be sensitive only to the relative fluctuations of the basic angle which the JASMINE wants to know and to be insensitive to the common one; in order to make the optical axis displacement caused by relative motion enhanced the Fabry-Perot cavity is formed by two mirrors which have long radius of curvature. To verify the principle of this idea, the experiment was performed using a 0.1m-length Fabry-Perot cavity with the mirror curvature of 20m. The mirrors of the cavity were artificially actuated in either relative way or common way and the resultant outputs from the sensor were compared.

  8. Automated high precision variable aperture for spectrophotometer linearity testing.

    PubMed

    Zwinkels, J C; Gignac, D S

    1991-05-01

    A new automated linearity tester with a single variable aperture has been designed and built. It uses piezoelectric motors to define precisely the apertures required for application of the double aperture method of light addition. This design avoids many of the inherent shortcomings of two fixed physically separated apertures, such as interference and coherence between two separated beams and the need for an averaging sphere to compensate for beam noncoincidence at the photoreceiver. It also permits the assessment of system nonlinearity for arbitrary flux levels over an approximately 70:1 dynamic range without the use of a supplementary means of optical attenuation. The tester was specifically designed for use with the National Research Council of Canada Reference spectrophotometer, but it can be adapted for use with any instrument with a large stable measurement beam. The paper discusses the correct placement and operation of this device. The performance, as evaluated by nonlinearity measurements of a known highly linear silicon photodiode, shows a reliability of <1-3 parts in 10(4) over a 3400:1 dynamic range at a 97% confidence level. Several applications of this linearity tester to both photomultipliers and photodiodes are described. Transmittance results for several reference materials using these linearity corrected photodetectors are compared and show a typical agreement of better than 0.025% of the value.

  9. High-precision target location for industrial metrology

    NASA Astrophysics Data System (ADS)

    Cosandier, D.; Chapman, Michael A.

    1993-02-01

    Many industrial metrology applications require accurate and real or near-real time measurement tools in often adverse conditions. Over the past three years, the Industrial Alignment Project (IAP) has been focused on the development of precise measurement techniques for use with large rotating machinery. This paper highlights some results using digital array cameras which have been shown to be well suited for many applications. Limited camera resolution and high accuracy point positioning requirements have required the development of specialized targets. Retro-reflective targets are used to reduce the varying effects of lighting/shadows since this material exhibits maximum reflection in the direction of the light source. Using sub-pixel edge detection techniques with the pre-defined targets, it is possible to obtain accuracies of 1/20th a pixel or better. In addition, employing multiple camera stations with an appropriate imaging geometry, the three dimensional coordinates of the point of interest can be obtained by establishing photogrammetric techniques. The results of test projects are given to illustrate the viability of such a measuring system.

  10. Interferometric apparatus for ultra-high precision displacement measurement

    NASA Technical Reports Server (NTRS)

    Zhao, Feng (Inventor)

    2004-01-01

    A high-precision heterodyne interferometer measures relative displacement by creating a thermally-insensitive system generally not subject to polarization leakage. By using first and second light beams separated by a small frequency difference (.DELTA.f), beams of light at the first frequency (f.sub.0) are reflected by co-axial mirrors, the first mirror of which has a central aperture through which the light is transmitted to and reflected by the second mirror. Prior to detection, the light beams from the two mirrors are combined with light of the second and slightly different frequency. The combined light beams are separated according to the light from the mirrors. The change in phase (.DELTA..phi.) with respect to the two signals is proportional to the change in distance of Fiducial B by a factor of wavelength (.lambda.) divided by 4.pi. (.DELTA.L=.lambda..DELTA..phi.1/(4.pi.)). In a second embodiment, a polarizing beam splitting system can be used.

  11. HST high-precision proper motions of globular clusters

    NASA Astrophysics Data System (ADS)

    Bellini, Andrea; Anderson, Jay; van der marel, roeland p.; piotto, gianpaolo; Watkins, Laura l.; Vesperini, Enrico; Milone, Antonino; Bedin, Luigi R.

    2015-08-01

    The stable environment of space makes HST an excellent astrometric tool. Its diffraction-limited resolution allows it to distinguish and measure positions and fluxes for stars all the way to the center of most globular clusters. There are now many clusters that have observations in the archive that span 13 years or more, and more observations are being taken all the time. We constructed high-precision proper-motion catalogs for over 20 clusters for which there exist two or more well-separated epochs in the archive, and we are extending the list to over 60 objects, thanks to the new observations taken within the ``HST UV Legacy Survey of Galactic Globular Clusters’’ treasury program. Each catalog contains astrometry and photometry for thousands of stars within two arcmin of the center. The catalogs are focused on the many stars within a few magnitudes of the turnoff and have typical proper-motion errors of 0.1 mas/yr, which translates to 2 km/s for the typical cluster. We are using proper motions to directly measure the clusters' anisotropy, equipartition and rotation on the plane of the sky, as well as to study internal kinematics of the different subpopulations and to probe the presence of an IMBH in their core.

  12. High-Precision Single Photon Timing of Pulsars

    NASA Astrophysics Data System (ADS)

    Ransom, Scott M.; Ray, Paul S.; Kerr, Matthew

    2017-08-01

    We have developed a likelihood-based technique, implemented through Markov Chain Monte Carlo, that enables high-precision pulsar timing using individual x-rays or gamma-rays. Our current implementaion leverages the new timing software PINT for timing model details and provides several significant advantages over earlier, more traditional, timing techniques. Our method does not require the integration of an average pulse profile from which a "time of arrival" is computed. This is crucial when the photon count rates are too low to produce a good pulse profile on the timescales of other important timing properties of the system (such as an orbital period of a binary pulsar). Arbitrary weights can be applied to each photon to indicate, for instance, the probability that each event might be a background photon. Many other improvements are being developed, such as simultaneously determining the timing solution and a template profile and parallel calculation of the likelihoods. We have successfully applied the technique to a variety of Fermi pulsars and will be using it extensively for timing analyses during the NICER mission.

  13. Measuring Crustal Deformation in Europe by High Precision Geodetic VLBI

    NASA Astrophysics Data System (ADS)

    Campbell, J.; Nothnagel, A.; Vennebusch, M.

    2002-06-01

    At the western tip of the Eurasian plate, the European continent is besieged by thrusting and receding neighbour plates causing deformations and ruptures of the Earth's crust evidenced by earthquakes and volcanic outbursts. Measuring the extent and progress of crustal deformation has become one of the primary tasks of geodesists and geophysicists. Realizing that Europe enjoys one of the densest networks of radio telescopes especially equipped for high precision, geodetic VLBI has provided the incentive to organise a campaign of regular geodetic VLBI observations in the European network of fixed radio telescopes. The measurements have been carried out since the late eighties at an average rate of six sessions per year. From these data, site coordinates, baseline length changes and station velocity vectors have been derived with steadily increasing accuracy. The overall picture of the observed present-day site motions emulates quite well the pattern of tectonic motions inferred from the geotectonic setting of central Europe and the western Mediterranean. Interesting details are emerging for horizontal motions of the three stations in Italy, which are strongly affected by the complex interactions between the different tectonic regimes in this area. The accuracy of the vertical components is also improving with increasing length of the observational record, allowing to detect significant trends among the relative vertical motions of the sites. The geodetic VLBI network operations have received supportive funding by the European Union under the 2nd and 4th Framework Programmes.

  14. High precision predictions for exclusive VH production at the LHC

    DOE PAGES

    Li, Ye; Liu, Xiaohui

    2014-06-04

    We present a resummation-improved prediction for pp → VH + 0 jets at the Large Hadron Collider. We focus on highly-boosted final states in the presence of jet veto to suppress the tt¯ background. In this case, conventional fixed-order calculations are plagued by the existence of large Sudakov logarithms αnslogm(pvetoT/Q) for Q ~ mV + mH which lead to unreliable predictions as well as large theoretical uncertainties, and thus limit the accuracy when comparing experimental measurements to the Standard Model. In this work, we show that the resummation of Sudakov logarithms beyond the next-to-next-to-leading-log accuracy, combined with the next-to-next-to-leading ordermore » calculation, reduces the scale uncertainty and stabilizes the perturbative expansion in the region where the vector bosons carry large transverse momentum. Thus, our result improves the precision with which Higgs properties can be determined from LHC measurements using boosted Higgs techniques.« less

  15. High Precision 40K/39K Ratio Determination

    NASA Astrophysics Data System (ADS)

    Naumenko, M. O.; Mezger, K.; Nagler, T. F.; Villa, I. M.

    2012-12-01

    Potassium is one of the eight most abundant chemical elements in the Earth's crust and a major element in many rock-forming minerals. The isotope 40K is radioactive and undergoes β- decay to 40Ca (ca. 89.3%) and electron capture to 40Ar (ca. 10.7%). Both decays can potentially be used as dating systems. The most commonly used branch is the decay of 40K to 40Ar because it can yield highly precise ages. Both decay schemes rely on the knowledge of the 40K branching ratio and the natural 40K abundance. A 40K abundance of 0.011672±41 % was measured on terrestrial material [1]. The relative uncertainty of 0.35 % has not been improved since. Recent improvements in the precision of mass spectrometric measurements have led to the situation that the uncertainties on the K decay constant and the abundance of 40K are a major source of uncertainty on the measured ages. A more precise definition of the 40K decay constant was attempted by different research groups within the last decade [2-9] but the goal of obtaining 0.1 % relative uncertainty on K-Ar ages for geological materials, as requested by the EARTHtime initiative, has not been achieved yet. In order to improve on this situation we studied the abundances of the K isotopes in terrestrial standards. A ThermoFischer Triton+ thermal ionisation mass spectrometer was used for K isotope ratio measurements of the NIST SRM 918b K standard loaded on Ta filaments with 0.1M phosphoric acid. Three techniques were applied: (A) dynamic measurement with in-run normalisation to the IUPAC value 41K/39K=0.072168; (B) a simple total evaporation procedure; (C) the "NBL-modified" total evaporation [10]. The 40K ion beam was measured in a Faraday cup with a 1E12 Ω resistor; 39K and 41K were collected in Faraday cups with 1E11 Ω resistors. Amplifier gains were intercalibrated by supplying fixed voltages off-line. Different measurement techniques were combined with different loading procedures. We also tested ionisation yields for the

  16. High-precision VLBI astrometry of radio-emitting stars

    NASA Astrophysics Data System (ADS)

    Lestrade, J.-F.; Preston, R. A.; Jones, D. L.; Phillips, R. B.; Rogers, A. E. E.; Titus, M. A.; Rioja, M. J.; Gabuzda, D. C.

    1999-04-01

    Multiple-epoch phase-referenced VLBI observations of 11 radio-emitting stars have been conducted as part of an astrometric program to link the Hipparcos optical reference frame to the radio extragalactic reference frame. We present the VLBI positions, proper motions and trigonometric parallaxes from this program in the ICRF (International Celestial Reference Frame). These astrometric parameters are absolute because they are directly measured relative to the distant quasars used as VLBI phase reference calibrators. The mean astrometric precision achieved relative to the calibrators is 0.36 milliarcsecond and the highest precision is for the RS CVn close binary sigma (2) CrB with formal uncertainties of 0.12 milliarcsecond for its relative position, 0.05 milliarcsecond for its annual proper motion and 0.10 milliarcsecond for its trigonometric parallax. In addition to the Hipparcos link, these observations have provided several new results. The distance to the nearby Tau-Auriga star forming region is 148 +/- 5 pc, determined directly through the VLBI trigonometric parallax of the Pre-Main-Sequence star HD283447 of this region. The orthogonality of the 2 orbital planes in the ternary system Algol is supported by new astrometric evidences. The proper motions of HR5110, HR1099 and IM Peg, regarded as possible guide stars for the NASA Gravity Probe B space mission, have formal precisions of 0.16, 0.31 and 0.40 milliarcsecond per year, respectively, and the mission requirement is 0.15 milliarcsecond per year. The close binary UX Ari is the only star that exhibits an acceleration larger than 3sigma and the most plausible cause is the gravitational interaction of a third body. The distances of the stars HD199178, IM Peg and AR Lac were uncertain by as much as 50% before our observations and are now 116 +/- 4, 97 +/- 6, 41.7 +/- 0.6 pc, respectively. The two X-ray binaries in our program, LSI61303 and Cyg X1, exhibit larger than expected post-fit position residuals. The

  17. Radiometric and Spectral Measurement Instruments

    DTIC Science & Technology

    1992-03-18

    NSWCCR/RDTN-92/0003 AD-A250 771LI~ llliii11l li l l iillt111 RADIOMETRIC AND SPECTRAL MEASUREMENT INSTRUMENTS CRANE DIVISION NAVAL SURFACE WARFARE... INSTRUMENTS 6. AUTHOR(S) B. E. DOUDA H. A. WEBSTER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) a. PERFORMING ORGANIZATION REPORT NIJMBER...Maxiry-um 200 w ords) THIS IS A DESCRIPTION OF AN ASSORTMENT OF RADIOMETRIC AND SPECTRAL INSTRUMENTATION USED FOR MEASUREMENT OF THE RADIATIVE OUTPUT OF

  18. French Meteor Network for High Precision Orbits of Meteoroids

    NASA Technical Reports Server (NTRS)

    Atreya, P.; Vaubaillon, J.; Colas, F.; Bouley, S.; Gaillard, B.; Sauli, I.; Kwon, M. K.

    2011-01-01

    There is a lack of precise meteoroids orbit from video observations as most of the meteor stations use off-the-shelf CCD cameras. Few meteoroids orbit with precise semi-major axis are available using film photographic method. Precise orbits are necessary to compute the dust flux in the Earth s vicinity, and to estimate the ejection time of the meteoroids accurately by comparing them with the theoretical evolution model. We investigate the use of large CCD sensors to observe multi-station meteors and to compute precise orbit of these meteoroids. An ideal spatial and temporal resolution to get an accuracy to those similar of photographic plates are discussed. Various problems faced due to the use of large CCD, such as increasing the spatial and the temporal resolution at the same time and computational problems in finding the meteor position are illustrated.

  19. Radio emission from Supernovae and High Precision Astrometry

    NASA Astrophysics Data System (ADS)

    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

  20. High frequency current conveyor precision full-wave rectifier

    NASA Astrophysics Data System (ADS)

    Toumazou, C.; Lidgey, F. J.; Chattong, S.

    1994-05-01

    The design of a precision full-wave rectifier using current conveyors is reported. The design uses a voltage reference circuit to clad the voltage excursions at the output of the rectifier during the zero crossings, which ensures that the usual large signal distortion associated with classical precision rectifiers is avoided. Measured rectifier performance using a 100 MHz current conveyor demonstrates good rectifier integrity at an operating frequency of 30 MHz.

  1. Identifying areas with potential for high indoor radon levels: analysis of the national airborne radiometric reconnaissance data for California and the Pacific Northwest

    SciTech Connect

    Moed, B.A.; Nazaroff, W.W.; Nero, A.V.; Schwehr, M.B.; Van Heuvelen, A.

    1984-04-01

    Radon-222 is an important indoor air pollutant which, through the inhalation of its radioactive decay products, accounts for nearly half of the effective dose equivalent to the public from natural ionizing radiation. Indoor radon concentrations vary widely, largely because of local and regional differences in the rate of entry from sources. The major sources are soil and rock near building foundations, earth-based building materials, and domestic water; of these, soil and rock are thought to be predominant in many buildings with higher-than-average concentrations. Thus, one key factor in determining radon source potential is the concentration of radium, the progenitor of radon, in surficial rocks and soils. Aerial radiometric data were analyzed, collected for the National Uranium Resource Evaluation Program, for seven Western states to: (1) provide information on the spatial distribution of radium contents in surficial geologic materials for those states; and (2) investigate approaches for using the aerial data, which have been collected throughout the contiguous United States and Alaska, to identify areas where high indoor radon levels may be common. Radium concentrations were found to be relatively low in central and western portions of Washington, Oregon, and northern California; they were found to be relatively high in central and southern California. A field validation study, conducted along two flight-line segments near Spokane, Washington, showed close correspondence between the aerial data, in situ measurements of both radium content and radon flux from soil, and laboratory measurements of both radium content of and radon emanation rate from soil samples. 99 references, 11 figures, 3 tables.

  2. Ultra High Precision Laser Monitor for Oxygen Eddy Flux Measurements

    NASA Astrophysics Data System (ADS)

    Zahniser, M. S.; Nelson, D. D.; Roscioli, J. R.; Herndon, S. C.; McManus, J. B.; Jervis, D.

    2015-12-01

    Atmospheric oxygen provides one of the most powerful tracers to study the carbon cycle through its close interaction with carbon dioxide. Keeling and co-workers demonstrated this at the global scale by using small variations in atmospheric oxygen content to disentangle oceanic and terrestrial carbon sinks. It would be very exciting to apply similar ideas at the ecosystem level to improve our understanding of biosphere-atmosphere exchange and our ability to predict the response of the biosphere and atmosphere to climate change. The eddy covariance technique is perhaps the most effective approach available to quantify the exchange of gases between these spheres. Therefore, eddy covariance flux measurements of oxygen would be extremely valuable. However, this requires a fast response (0.1 seconds), high relative precision (0.001% or 10 per meg) oxygen sensor. We report recent progress in developing such a sensor using a high resolution visible laser to probe the oxygen A-band electronic transition. This sensor will enable oxygen flux measurements using eddy covariance. In addition, we will incorporate a second laser in this instrument to simultaneously determine the fluxes of oxygen, carbon dioxide and water vapor within the same sampling cell. This will provide a direct, real time measurement of the ratio of the flux of oxygen to that of carbon dioxide. This ratio is expected to vary on short time scales and small spatial scales due to the differing stoichiometry of processes producing and consuming carbon dioxide. Thus measuring the variations in the ratio of oxygen and carbon dioxide fluxes will provide mechanistic information to improve our understanding of the crucial exchange of carbon between the atmosphere and biosphere.

  3. HIGH-PRECISION ASTROMETRY WITH A DIFFRACTIVE PUPIL TELESCOPE

    SciTech Connect

    Guyon, Olivier; Eisner, Josh A.; Angel, Roger; Woolf, Neville J.; Bendek, Eduardo A.; Milster, Thomas D.; Mark Ammons, S.; Shao, Michael; Shaklan, Stuart; Levine, Marie; Nemati, Bijan; Pitman, Joe; Woodruff, Robert A.; Belikov, Ruslan

    2012-06-01

    Astrometric detection and mass determination of Earth-mass exoplanets require sub-{mu}as accuracy, which is theoretically possible with an imaging space telescope using field stars as an astrometric reference. The measurement must, however, overcome astrometric distortions, which are much larger than the photon noise limit. To address this issue, we propose to generate faint stellar diffraction spikes using a two-dimensional grid of regularly spaced small dark spots added to the surface of the primary mirror (PM). Accurate astrometric motion of the host star is obtained by comparing the position of the spikes to the background field stars. The spikes do not contribute to scattered light in the central part of the field and therefore allow unperturbed coronagraphic observation of the star's immediate surroundings. Because the diffraction spikes are created on the PM and imaged on the same focal plane detector as the background stars, astrometric distortions affect equally the diffraction spikes and the background stars and are therefore calibrated. We describe the technique, detail how the data collected by the wide-field camera are used to derive astrometric motion, and identify the main sources of astrometric error using numerical simulations and analytical derivations. We find that the 1.4 m diameter telescope, 0.3 deg{sup 2} field we adopt as a baseline design achieves 0.2 {mu}as single measurement astrometric accuracy. The diffractive pupil concept thus enables sub-{mu}as astrometry without relying on the accurate pointing, external metrology, or high-stability hardware required with previously proposed high-precision astrometry concepts.

  4. High precision metrology based microwave effective linewidth measurement technique

    SciTech Connect

    Mo, Nan; Green, Jerome J.; Beitscher, Bailey A.; Patton, Carl E.

    2007-11-15

    A precision microwave effective linewidth measurement technique for magnetic samples has been developed. The measurement utilizes a high-Q cylindrical cavity that contains the sample of interest, a highly stable and programable static magnetic field source, a computer controlled network analyzer for cavity center frequency {omega}{sub c} and quality factor Q{sub c} determinations, and the standard metrological substitution ABA method for accurate relative {omega}{sub c} and Q{sub c} measurements. Sequential long term ABA measurements show that the time and temperature drifts and random errors are the dominant sources of error, with uncertainties in {omega}{sub c}/2{pi} and Q{sub c} in the range of 50 kHz and 25, respectively. The ABA method is applied to eliminate these drifts and minimize the random errors. For measurements over 25 ABA cycles, accuracy is improved to 0.14 kHz for {omega}{sub c}/2{pi} and 3 for Q{sub c}. The temperature variation over a single ABA cycle is generally on the order of 10{sup -3}-10{sup -5} deg. C and there is no need for any further temperature stabilization or correction measures. The overall uncertainty in the 10 GHz effective linewidth determinations for a 3 mm diam, 0.5 mm thick polycrystalline yttrium iron garnet (YIG) disk is 0.15 Oe or less, well below the intrinsic single crystal YIG linewidth. This represents a factor of 10 improvement in measurement accuracy over previous work.

  5. Injector linac stability requirements for high precision experiments at MESA

    NASA Astrophysics Data System (ADS)

    Hug, F.; Heine, R.

    2017-07-01

    MESA is a recirculating superconducting accelerator under construction at Johannes Gutenberg-Universität Mainz. It will be used for high precision particle physics experiments in two different operation modes: external beam (EB) mode and energy recovery (ERL) mode. The operating beam current and energy in EB mode is 0.15 mA with polarized electrons at 155 MeV. In ERL mode an unpolarized beam of 1 mA at 105 MeV will be available. In a later construction stage of MESA the beam current in ERL-mode shall be upgraded to 10 mA. In order to achieve high beam stability and low energy spread in recirculating operation for external beam the acceleration in the main linac sections will be done on a certain phase with respect to the maximum of the accelerating field (off crest) while the return arcs provide longitudinal dispersion. On specific longitudinal working points this can result in a setting where any RF phase or magnitude jitters from main linac do not contribute to the resulting energy spread of the final beam at all. Then the resulting energy spread of the beam at the experiment is mostly determined by the beam properties provided by the injector linac. On the other hand the acceleration in ERL operation mode most likely needs to be done on crest of the accelerating field aiming for the highest efficiency in the energy recovering process albeit we are currently investigating different recirculation schemes for the ERL mode as well. Using on crest acceleration the achievable energy spread is determined by the longitudinal phase space properties behind the injector linac again but mostly by the bunch length of the beam injected to the main linac. Within this contribution we will investigate the requirements on the stability of the MESA injector linac MAMBO for achieving the experimental goals under both operating conditions.

  6. The Candela and Photometric and Radiometric Measurements

    PubMed Central

    Parr, Albert C.

    2001-01-01

    The national measurement system for photometric and radiometric quantities is presently based upon techniques that make these quantities traceable to a high-accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high-temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of photometric quantities upon absolute detector based technology as was allowed by the 1979 redefinition. Additionally, the development of improved photodetectors has had a significant impact on the methodology in most of the radiometric measurement areas. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements. PMID:27500020

  7. Precision optical slit for high heat load or ultra high vacuum

    DOEpatents

    Andresen, N.C.; DiGennaro, R.S.; Swain, T.L.

    1995-01-24

    This invention relates generally to slits used in optics that must be precisely aligned and adjusted. The optical slits of the present invention are useful in x-ray optics, x-ray beam lines, optical systems in which the entrance slit is critical for high wavelength resolution. The invention is particularly useful in ultra high vacuum systems where lubricants are difficult to use and designs which avoid the movement of metal parts against one another are important, such as monochromators for high wavelength resolution with ultra high vacuum systems. The invention further relates to optical systems in which temperature characteristics of the slit materials is important. The present invention yet additionally relates to precision slits wherein the opposing edges of the slit must be precisely moved relative to a center line between the edges with each edge retaining its parallel orientation with respect to the other edge and/or the center line. 21 figures.

  8. Precision optical slit for high heat load or ultra high vacuum

    DOEpatents

    Andresen, Nord C.; DiGennaro, Richard S.; Swain, Thomas L.

    1995-01-01

    This invention relates generally to slits used in optics that must be precisely aligned and adjusted. The optical slits of the present invention are useful in x-ray optics, x-ray beam lines, optical systems in which the entrance slit is critical for high wavelength resolution. The invention is particularly useful in ultra high vacuum systems where lubricants are difficult to use and designs which avoid the movement of metal parts against one another are important, such as monochrometers for high wavelength resolution with ultra high vacuum systems. The invention further relates to optical systems in which temperature characteristics of the slit materials is important. The present invention yet additionally relates to precision slits wherein the opposing edges of the slit must be precisely moved relative to a center line between the edges with each edge retaining its parallel orientation with respect to the other edge and/or the center line.

  9. Simultaneous Precision Gravimetry and Magnetic Gradiometry with a Bose-Einstein Condensate: A High Precision, Quantum Sensor.

    PubMed

    Hardman, K S; Everitt, P J; McDonald, G D; Manju, P; Wigley, P B; Sooriyabandara, M A; Kuhn, C C N; Debs, J E; Close, J D; Robins, N P

    2016-09-23

    A Bose-Einstein condensate is used as an atomic source for a high precision sensor. A 5×10^{6}  atom F=1 spinor condensate of ^{87}Rb is released into free fall for up to 750 ms and probed with a T=130  ms Mach-Zehnder atom interferometer based on Bragg transitions. The Bragg interferometer simultaneously addresses the three magnetic states |m_{f}=1,0,-1⟩, facilitating a simultaneous measurement of the acceleration due to gravity with a 1000 run precision of Δg/g=1.45×10^{-9} and the magnetic field gradient to a precision of 120  pT/m.

  10. High-precision photometry of WASP-12 b transits

    NASA Astrophysics Data System (ADS)

    Maciejewski, G.; Errmann, R.; Raetz, St.; Seeliger, M.; Spaleniak, I.; Neuhäuser, R.

    2011-04-01

    Aims: The transiting extrasolar planet WASP-12 b was found to be one of the most intensely irradiated exoplanets. It is unexpectedly bloated and is losing mass that may accrete into the host star. Our aim was to refine the parameters of this intriguing system and search for signs of transit timing variations. Methods: We gathered high-precision light curves for two transits of WASP-12 b. Assuming various limb-darkening laws, we generated best-fitting models and redetermined the parameters of the system. Error estimates were derived by the prayer-bead method and Monte Carlo simulations. Results: System parameters obtained by us are found to agree with previous studies within one sigma. Use of the non-linear limb-darkening laws results in the best-fitting models. With two new mid-transit times, the ephemeris was refined to BJDTDB = (2 454 508.97682 ± 0.00020) + (1.09142245 ± 0.00000033)E. Interestingly, indications of transit timing variation are detected at the level of 3.4 sigma. This signal can be induced by an additional planet in the system. Simplified numerical simulations show that a perturber could be a terrestrial-type planet if both planets are in a low-order orbital resonance. However, we emphasise that further observations are needed to confirm variation and to constrain properties of the perturber. Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA), operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofisica de Andalucia (CSIC).Photometric data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/528/A65

  11. High Precision Prediction of Functional Sites in Protein Structures

    PubMed Central

    Buturovic, Ljubomir; Wong, Mike; Tang, Grace W.; Altman, Russ B.; Petkovic, Dragutin

    2014-01-01

    We address the problem of assigning biological function to solved protein structures. Computational tools play a critical role in identifying potential active sites and informing screening decisions for further lab analysis. A critical parameter in the practical application of computational methods is the precision, or positive predictive value. Precision measures the level of confidence the user should have in a particular computed functional assignment. Low precision annotations lead to futile laboratory investigations and waste scarce research resources. In this paper we describe an advanced version of the protein function annotation system FEATURE, which achieved 99% precision and average recall of 95% across 20 representative functional sites. The system uses a Support Vector Machine classifier operating on the microenvironment of physicochemical features around an amino acid. We also compared performance of our method with state-of-the-art sequence-level annotator Pfam in terms of precision, recall and localization. To our knowledge, no other functional site annotator has been rigorously evaluated against these key criteria. The software and predictive models are incorporated into the WebFEATURE service at http://feature.stanford.edu/wf4.0-beta. PMID:24632601

  12. High-precision U-Pb zircon age from the Triassic of Italy: Implications for the Triassic time scale and the Carnian origin of calcareous nannoplankton and dinosaurs

    NASA Astrophysics Data System (ADS)

    Furin, Stefano; Preto, Nereo; Rigo, Manuel; Roghi, Guido; Gianolla, Piero; Crowley, James L.; Bowring, Samuel A.

    2006-12-01

    The Triassic time scale is poorly constrained due to a paucity of high-precision radiometric ages. We present a 206Pb/238U age of 230.91 ± 0.33 Ma (error includes all known sources) for zircon from an ash bed in the upper Carnian (Upper Triassic) of southern Italy that requires a major revision of the Triassic time scale. For example, the Norian stage is lengthened to more than 20 m.y. The section containing the ash bed is correlated with other Tethyan sections and, indirectly, with the Newark astronomical polarity time scale (APTS). The dating provides also a minimum age for some important climatic and biotic events that occurred during the Carnian. We note a coincidence between these events and the eruption of the large igneous province of Wrangellia, but the possible link between volcanism and climatic and biotic events requires further scrutiny.

  13. A Comparison of three high-precision quadrature schemes

    SciTech Connect

    Bailey, David H.; Li, Xiaoye S.

    2003-07-01

    The authors have implemented three numerical quadrature schemes, using the new Arbitrary Precision (ARPREC) software package, with the objective of seeking a completely ''automatic'' arbitrary precision quadrature facility, namely one that does not rely on a priori information of the function to be integrated. Such a facility is required, for example, to permit the experimental identification of definite integrals based on their numerical values. The performance and accuracy of these three quadrature schemes are compared using a suite of 15 integrals, ranging from continuous, well-behaved functions on finite intervals to functions with vertical derivatives and integrable singularities at endpoints, as well as several integrals on an infinite interval.

  14. High-Precision Coupling Mechanism Operable By Robots

    NASA Technical Reports Server (NTRS)

    Voellmer, George

    1992-01-01

    Coupling mechanism has features making it easily operable by hand and suitable for operation by robots: tolerates some initial misalignment, imposes precise final alignment, and protects itself against overtightening. Typically used to mount equipment module on structure. Mechanism includes kinematic mounts, which tolerate small initial misalignment and enforce precise final alignment as two assemblies brought together. Clamping force applied to kinematic mounts via two flexible plates. Bolt and nut tightened on flexible plates to impose spring clamping load. Repeatability of interface tested and found to be better than forty-millionths of inch.

  15. High-Precision Coupling Mechanism Operable By Robots

    NASA Technical Reports Server (NTRS)

    Voellmer, George

    1992-01-01

    Coupling mechanism has features making it easily operable by hand and suitable for operation by robots: tolerates some initial misalignment, imposes precise final alignment, and protects itself against overtightening. Typically used to mount equipment module on structure. Mechanism includes kinematic mounts, which tolerate small initial misalignment and enforce precise final alignment as two assemblies brought together. Clamping force applied to kinematic mounts via two flexible plates. Bolt and nut tightened on flexible plates to impose spring clamping load. Repeatability of interface tested and found to be better than forty-millionths of inch.

  16. High precision ages from the Torres del Paine Intrusion, Chile

    NASA Astrophysics Data System (ADS)

    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

  17. CUSB-II: a high precision electromagnetic spectrometer

    NASA Astrophysics Data System (ADS)

    Schamberger, R. D.; Heintz, U.; Lee-Franzini, J.; Lovelock, D. M. J.; Narain, M.; Willins, J.; Yanagisawa, C.; Tuts, P. M.; Franzini, P.; Kanekal, S.; Wu, Q. W.

    1991-11-01

    The design, construction and performance of a very compact precision electromagnetic spectrometer is described. The CUSB-II detector has been used to study ϒ spectroscopy, search for exotic particles and measure properties of the B and B ∗ mesons at the Cornell Electron Storage Ring.

  18. High-precision Stellar Limb-darkening in Exoplanetary Transits

    NASA Astrophysics Data System (ADS)

    Morello, G.; Tsiaras, A.; Howarth, I. D.; Homeier, D.

    2017-09-01

    Characterization of the atmospheres of transiting exoplanets relies on accurate measurements of the extent of the optically thick area of the planet at multiple wavelengths with a precision ≲ 100 parts per million (ppm). Next-generation instruments onboard the James Webb Space Telescope (JWST) are expected to achieve ∼10 ppm precision for several tens of targets. A similar precision can be obtained in modeling only if other astrophysical effects, including the stellar limb-darkening, are properly accounted for. In this paper, we explore the limits on precision due to the mathematical formulas currently adopted to approximate the stellar limb-darkening, and due to the use of limb-darkening coefficients obtained either from stellar-atmosphere models or empirically. We recommend the use of a two-coefficient limb-darkening law, named “power-2,” which outperforms other two-coefficient laws adopted in the exoplanet literature in most cases, and particularly for cool stars. Empirical limb-darkening based on two-coefficient formulas can be significantly biased, even if the light-curve residuals are nearly photon-noise limited. We demonstrate an optimal strategy to fitting for the four-coefficient limb-darkening in the visible, using prior information on the exoplanet orbital parameters to break some of the degeneracies that otherwise would prevent the convergence of the fit. Infrared observations taken with the JWST will provide accurate measurements of the exoplanet orbital parameters with unprecedented precision, which can be used as priors to improve the stellar limb-darkening characterization, and therefore the inferred exoplanet parameters, from observations in the visible, such as those taken with Kepler/K2, the JWST, and other past and future instruments.

  19. The Precambrian Singo Igneous Complex (SIC), Uganda Revealed As a Mineralized Nested Ring Complex Using High Resolution Airborne Radiometric and Magnetic Data.

    NASA Astrophysics Data System (ADS)

    Atekwana, E. A.; LePera, A.; Abdelsalam, M. G.; Katumwehe, A. B.; Achang, M.

    2014-12-01

    We used high-resolution radiometrics and aeromagnetic data to investigate the Precambrian Singo Igneous Complex (SIC) in Uganda. The SIC covers an area of about 700 km² and is host to hydrothermally formed economic minerals such as Gold and Tungsten. The distribution of the ore deposits is not well known and current mine workings are limited to the western margins of the complex. Our objectives were to (1) provide a detailed geological map of the SIC and surrounding, (2) investigate relationships between preserved intrusive bodies and Precambrian tectonic structures to provide insight into emplacement of the complex, (3) examine links between magma emplacement, discontinuities and hydrothermal alteration (4) generate two-dimensional (2-D) and three-dimensional (3-D) models of the complex to understand its subsurface geometry, (5) investigate the relationship between the structure of the SIC and mineral occurrences as an aid to future exploration programs. Edge enhancement filters such as the analytical signal, vertical and tilt derivatives were applied to the magnetic data. In addition, 2-D and 3-D models were produced using Geosoft's GM-SYS 2-D and Voxi modules. The filtered data provided unprecedented structural details of the complex and revealed the following: (1) the edge of the SIC is characterized by higher magnetic susceptibility and Thorium content than its interior, (2) the SIC is characterized by eight to nine nested ring complexes with diameters ranging from 2.5 to 14 km, (3) the 3-D inversion suggests near vertical walls for the ring complexes extending to a depth of about 7 km, (4) the SIC was emplaced within a Precambrian folded basement and was traversed by numerous NW-trending dykes and (5) present day mining activities are concentrated within the folded basement units although occurrences of Tungsten and Gold are found associated with the highly magnetized edge of the ring complexes. We interpret the highly magnetized edges of the nested ring

  20. New high precision U-Pb calibration of the late Early-Triassic (Smithian-Spathian Boundary, South China)

    NASA Astrophysics Data System (ADS)

    Widmann, Philipp; Leu, Marc; Goudemand, Nicolas; Schaltegger, Urs; Bucher, Hugo

    2017-04-01

    Following the Permian-Triassic mass extinction (PTME), the Early Triassic is characterized by large short-lived perturbations of the global carbon cycle associated with radiation and extinction pulses of the biota. More stable conditions resumed in the Middle Triassic (Anisian). The exact ages and duration of these short-lived but intense radiation-extinction events as well as carbon cycle perturbations are poorly constrained and a robust intercalibration of U-Pb dates, biochronozones and carbon isotope fluctuations is still lacking. An accurate and precise time frame is essential in order to quantify the dynamics of the underlying mechanistic processes and to assess the validity of the various explanatory scenarios. The most drastic Early Triassic extinction occurred at the Smithian-Spathian boundary (SSB) and is associated with a globally recognized sharp positive excursion of the marine d13C signal. Based on the most recently published ages for the Permian-Triassic boundary (251.938 ± 0.029 Ma, Baresel et al., 2016) and for the Early-Middle Triassic boundary (247.05 ± 0.16 Ma, Ovtcharova et al., 2015), we know the Early Triassic lasted 4.9 myr. However, neither the position of the SSB nor the durations of the major biotic and abiotic events around the SSB are constrained by radiometric dates. Here, we will present new high precision, chemical abrasion, isotope dilution, thermal ionization mass spectrometry (CA-ID-TIMS) U-Pb ages from single zircon crystals, sampled from closely spaced volcanic ash layers that bracket the SSB in the Nanpanjiang Basin (Guizhou province, South China). These ash layers are found in a mixed carbonate-siliciclastic, conodont-rich sedimentary succession (Luolou Formation) that is well calibrated biochronologically. We obtained best estimates of the ages of the SSB and associated events by applying Bayesian age modelling. References: Baresel, B., Bucher, H., Brosse, M., Cordey, F., Guodun, K., and Schaltegger, U., 2016. Precise age

  1. Preliminary design approach for large high precision segmented reflectors

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr.; Collins, Timothy J.; Hedgepeth, John M.

    1990-01-01

    A simplified preliminary design capability for erectable precision segmented reflectors is presented. This design capability permits a rapid assessment of a wide range of reflector parameters as well as new structural concepts and materials. The preliminary design approach was applied to a range of precision reflectors from 10 meters to 100 meters in diameter while considering standard design drivers. The design drivers considered were: weight, fundamental frequency, launch packaging volume, part count, and on-orbit assembly time. For the range of parameters considered, on-orbit assembly time was identified as the major design driver. A family of modular panels is introduced which can significantly reduce the number of reflector parts and the on-orbit assembly time.

  2. Joint Estimation of Multiple High-dimensional Precision Matrices

    PubMed Central

    Cai, T. Tony; Li, Hongzhe; Liu, Weidong; Xie, Jichun

    2017-01-01

    Motivated by analysis of gene expression data measured in different tissues or disease states, we consider joint estimation of multiple precision matrices to effectively utilize the partially shared graphical structures of the corresponding graphs. The procedure is based on a weighted constrained ℓ∞/ℓ1 minimization, which can be effectively implemented by a second-order cone programming. Compared to separate estimation methods, the proposed joint estimation method leads to estimators converging to the true precision matrices faster. Under certain regularity conditions, the proposed procedure leads to an exact graph structure recovery with a probability tending to 1. Simulation studies show that the proposed joint estimation methods outperform other methods in graph structure recovery. The method is illustrated through an analysis of an ovarian cancer gene expression data. The results indicate that the patients with poor prognostic subtype lack some important links among the genes in the apoptosis pathway.

  3. Ion source for high-precision mass spectrometry

    DOEpatents

    Todd, Peter J.; McKown, Henry S.; Smith, David H.

    1984-01-01

    The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit.

  4. High-precision dynamic orbit integration for spaceborne gravimetry

    NASA Astrophysics Data System (ADS)

    Ellmer, M.; Mayer-Gürr, T.

    2016-12-01

    Future gravity missions like GRACE Follow-On and beyond will deliver low-low satellite-to-satellite ranging measurements of much increased precision. To prepare for the new challenges and opportunities involved in processing this new data, it is necessary to perform a systematic review and re-evaluation of current algorithms and assumptions used in gravity field determination from GRACE data. In this context, this study investigates the computation of dynamic orbits from GRACE accelerometer measurements and background models, which are used at multiple steps in gravity recovery. They are, for example, used in computing linearised observation equations for the low-low satellite-to-satellite tracking instruments, or to evaluate potential models like static fields or dealiasing products. It is thus desirable for the precision at which the dynamic orbits are determined to surpass the precision of the ranging observations. We computed dynamic orbits for GRACE, both in a simple simulation and for real observational data. We observed the differences between successive iterations of orbit determination and used these as a benchmark for the quality of the orbit solution. We implemented a numerically stable orbit determination algorithm employing Encke's method, in which we use a novel reference trajectory determined through rigorous optimization. This reference trajectory was parameterised and computed using equinoctial elements to minimize orbit errors resulting from imprecision in the reference motion. We present the effects of these two optimizations on the dynamic orbits, and show that the resulting orbits are self-consistent to below the expected precision of the GRACE Follow-On ranging instruments.

  5. Ion source for high-precision mass spectrometry

    DOEpatents

    Todd, P.J.; McKown, H.S.; Smith, D.H.

    1982-04-26

    The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit. 2 figures, 3 tables.

  6. Yale High Energy Physics Research: Precision Studies of Reactor Antineutrinos

    SciTech Connect

    Heeger, Karsten M.

    2014-09-13

    This report presents experimental research at the intensity frontier of particle physics with particular focus on the study of reactor antineutrinos and the precision measurement of neutrino oscillations. The experimental neutrino physics group of Professor Heeger and Senior Scientist Band at Yale University has had leading responsibilities in the construction and operation of the Daya Bay Reactor Antineutrino Experiment and made critical contributions to the discovery of non-zero$\\theta_{13}$. Heeger and Band led the Daya Bay detector management team and are now overseeing the operations of the antineutrino detectors. Postdoctoral researchers and students in this group have made leading contributions to the Daya Bay analysis including the prediction of the reactor antineutrino flux and spectrum, the analysis of the oscillation signal, and the precision determination of the target mass yielding unprecedented precision in the relative detector uncertainty. Heeger's group is now leading an R\\&D effort towards a short-baseline oscillation experiment, called PROSPECT, at a US research reactor and the development of antineutrino detectors with advanced background discrimination.

  7. Gauges for Highly Precise Metrology of a Compound Mirror

    NASA Technical Reports Server (NTRS)

    Gursel, Yekta

    2005-01-01

    Three optical gauges have been developed for guiding the assembly and measuring precisely the reflecting surfaces of a compound mirror that comprises a corner-cube retroreflector glued in a hole on a flat mirror. In the specific application for which the gauges were developed, the compound mirror is part of a siderostat in a stellar interferometer. The flat-mirror portion of the compound mirror is the siderostat mirror; the retroreflector portion of the compound mirror is to be used, during operation of the interferometer, to monitor the location of the siderostat mirror surface relative to other optical surfaces of the interferometer. Nominally, the optical corner of the retroreflector should lie precisely on the siderostat mirror surface, but this precision cannot be achieved in fabrication: in practice, there remains some distance between the optical corner and the siderostat mirror surface. For proper operation of the interferometer, it is required to make this distance as small as possible and to know this distance within 1 nm. The three gauges make it possible to satisfy these requirements.

  8. Radiometric framework for image mosaicking.

    PubMed

    Litvinov, Anatoly; Schechner, Yoav Y

    2005-05-01

    Nonuniform exposures often affect imaging systems, e.g., owing to vignetting. Moreover, the sensor's radiometric response may be nonlinear. These characteristics hinder photometric measurements. They are particularly annoying in image mosaicking, in which images are stitched to enhance the field of view. Mosaics suffer from seams stemming from radiometric inconsistencies between raw images. Prior methods feathered the seams but did not address their root cause. We handle these problems in a unified framework. We suggest a method for simultaneously estimating the radiometric response and the camera nonuniformity, based on a frame sequence acquired during camera motion. The estimated functions are then compensated for. This permits image mosaicking, in which no seams are apparent. There is no need to resort to dedicated seam-feathering methods. Fundamental ambiguities associated with this estimation problem are stated.

  9. Airborne microwave radiometric imaging system

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Zhang, Zuyin; Chen, Zhengwen

    1998-08-01

    A dual channel Airborne Microwave Radiometric Imaging system (AMRI) was designed and constructed for regional environment mapping. The system operates at 35GHz, which collects radiation at horizontal and vertical polarized. It runs at mechanical conical scanning with 45 degrees incidence angle. Two Cassegrain antennas with 1.5 degrees 3 dB beamwidth scan the scene alternately and two pseudo-color images of two channels are displayed on the screen of PC in real time. Simultaneously all parameters of flight and radiometric data are stored in hard disk for postprocessing. The sensitivity of the radiometers of flight and radiometric data are stored in hard disk for postprocessing. The sensitivity of the radiometers (Delta) T equals 0.16K. A new display method, unequal size element arc displaying method, is used in image displaying. Several experiments on mobile tower were carried out and the images demonstrate the AMRI is available to work steadily and accurately.

  10. Visual Inspection of Machined Metallic High-Precision Surfaces

    NASA Astrophysics Data System (ADS)

    Pernkopf, Franz; O'Leary, Paul

    2002-12-01

    This paper presents a surface inspection prototype of an automatic system for precision ground metallic surfaces, in this case bearing rolls. The surface reflectance properties are modeled and verified with optical experiments. The aim being to determine the optical arrangement for illumination and observation, where the contrast between errors and intact surface is maximized. A new adaptive threshold selection algorithm for segmentation is presented. Additionally, is included an evaluation of a large number of published sequential search algorithms for selection of the best subset of features for the classification with a comparison of their computational requirements. Finally, the results of classification for 540 flaw images are presented.

  11. High Precision Material Study at Near Millimeter Wavelengths.

    DTIC Science & Technology

    1983-08-30

    Laser, Rexolite, TPX , Dynasil 4000. LQj .~4 20.1 ABSR*ACT ’Cath- do -- e8e11110 if nmwe*my selIdenti by block n"Whe") ’-2 Various quasi-optical...pyroelectric detectors (Laser Precision Rkp-545): L L, and L TPx lens; BS1, wire-mesh beam splitter; BS, mylar-film beam splitter; DPC, double-prism coupler...focused at the entrance to the guide with a waist radius of approximately 0.6435a, where a is the radius of the guide. A lens made from TPX plastic was

  12. High precision high voltage divider and its application to electron beam ion traps

    SciTech Connect

    Chen, W. D.; Xiao, J.; Shen, Y.; Fu, Y. Q.; Meng, F. C.; Chen, C. Y.; Zou, Y.; Hutton, R.

    2008-12-15

    A high precision high voltage divider has been developed for the electron beam ion trap in Shanghai. The uncertainty caused by the temperature coefficient of resistance (TCR) and the voltage coefficient of resistance has been studied in detail and was minimized to the level of ppm (10{sup -6}) range. Once the TCR was matched between the resistors, the precision of the dividing ratio finally reached the ppm range also. We measured the delay of the divider caused by the capacitor introduced to minimize voltage ripple to be 2.35 ms. Finally we applied the divider to an experiment to measure resonant energies for some dielectronic recombination processes for highly charged xenon ions. The final energies include corrections for both space charge and fringe field effects are mostly under 0.03%.

  13. A high precision, compact electromechanical ground rotation sensor

    SciTech Connect

    Dergachev, V.; DeSalvo, R.; Asadoor, M.; Bhawal, A.; Gong, P.; Kim, C.; Lottarini, A.; Minenkov, Y.; Murphy, C.; O'Toole, A.; Peña Arellano, F. E.; and others

    2014-05-15

    We present a mechanical rotation sensor consisting of a balance pivoting on a tungsten carbide knife edge. These sensors are important for precision seismic isolation systems, as employed in land-based gravitational wave interferometers and for the new field of rotational seismology. The position sensor used is an air-core linear variable differential transformer with a demonstrated noise floor of 1 × 10{sup −11}m/√( Hz ). We describe the instrument construction and demonstrate low noise operation with a noise floor upper bound of 5.7 × 10{sup −9} rad /√( Hz ) at 10 mHz and 6.4 × 10{sup −10} rad /√( Hz ) at 0.1 Hz. The performance of the knife edge hinge is compatible with a behaviorur free of noise from dislocation self-organized criticality.

  14. Decade-Spanning High-Precision Terahertz Frequency Comb

    NASA Astrophysics Data System (ADS)

    Finneran, Ian A.; Good, Jacob T.; Holland, Daniel B.; Carroll, P. Brandon; Allodi, Marco A.; Blake, Geoffrey A.

    2015-04-01

    The generation and detection of a decade-spanning terahertz (THz) frequency comb is reported using two Ti:sapphire femtosecond laser oscillators and asynchronous optical sampling THz time-domain spectroscopy. The comb extends from 0.15 to 2.4 THz, with a tooth spacing of 80 MHz, a linewidth of 3.7 kHz, and a fractional precision of 1.8 ×10-9 . With time-domain detection of the comb, we measure three transitions of water vapor at 10 mTorr between 1-2 THz with an average Doppler-limited fractional accuracy of 6.1 ×10-8 . Significant improvements in bandwidth, resolution, and sensitivity are possible with existing technologies.

  15. A high precision, compact electromechanical ground rotation sensor.

    PubMed

    Dergachev, V; DeSalvo, R; Asadoor, M; Bhawal, A; Gong, P; Kim, C; Lottarini, A; Minenkov, Y; Murphy, C; O'Toole, A; Peña Arellano, F E; Rodionov, A V; Shaner, M; Sobacchi, E

    2014-05-01

    We present a mechanical rotation sensor consisting of a balance pivoting on a tungsten carbide knife edge. These sensors are important for precision seismic isolation systems, as employed in land-based gravitational wave interferometers and for the new field of rotational seismology. The position sensor used is an air-core linear variable differential transformer with a demonstrated noise floor of 1 × 10⁻¹¹ m/√Hz. We describe the instrument construction and demonstrate low noise operation with a noise floor upper bound of 5.7 × 10⁻⁹ rad/√Hz at 10 mHz and 6.4 × 10⁻¹⁰ rad/√Hz at 0.1 Hz. The performance of the knife edge hinge is compatible with a behaviorur free of noise from dislocation self-organized criticality.

  16. Aerospace Laser Ignition/Ablation Variable High Precision Thruster

    NASA Technical Reports Server (NTRS)

    Campbell, Jonathan W. (Inventor); Edwards, David L. (Inventor); Campbell, Jason J. (Inventor)

    2015-01-01

    A laser ignition/ablation propulsion system that captures the advantages of both liquid and solid propulsion. A reel system is used to move a propellant tape containing a plurality of propellant material targets through an ignition chamber. When a propellant target is in the ignition chamber, a laser beam from a laser positioned above the ignition chamber strikes the propellant target, igniting the propellant material and resulting in a thrust impulse. The propellant tape is advanced, carrying another propellant target into the ignition chamber. The propellant tape and ignition chamber are designed to ensure that each ignition event is isolated from the remaining propellant targets. Thrust and specific impulse may by precisely controlled by varying the synchronized propellant tape/laser speed. The laser ignition/ablation propulsion system may be scaled for use in small and large applications.

  17. Decade-spanning high-precision terahertz frequency comb.

    PubMed

    Finneran, Ian A; Good, Jacob T; Holland, Daniel B; Carroll, P Brandon; Allodi, Marco A; Blake, Geoffrey A

    2015-04-24

    The generation and detection of a decade-spanning terahertz (THz) frequency comb is reported using two Ti:sapphire femtosecond laser oscillators and asynchronous optical sampling THz time-domain spectroscopy. The comb extends from 0.15 to 2.4 THz, with a tooth spacing of 80 MHz, a linewidth of 3.7 kHz, and a fractional precision of 1.8×10^{-9}. With time-domain detection of the comb, we measure three transitions of water vapor at 10 mTorr between 1-2 THz with an average Doppler-limited fractional accuracy of 6.1×10^{-8}. Significant improvements in bandwidth, resolution, and sensitivity are possible with existing technologies.

  18. A high precision, compact electromechanical ground rotation sensor

    NASA Astrophysics Data System (ADS)

    Dergachev, V.; DeSalvo, R.; Asadoor, M.; Bhawal, A.; Gong, P.; Kim, C.; Lottarini, A.; Minenkov, Y.; Murphy, C.; O'Toole, A.; Peña Arellano, F. E.; Rodionov, A. V.; Shaner, M.; Sobacchi, E.

    2014-05-01

    We present a mechanical rotation sensor consisting of a balance pivoting on a tungsten carbide knife edge. These sensors are important for precision seismic isolation systems, as employed in land-based gravitational wave interferometers and for the new field of rotational seismology. The position sensor used is an air-core linear variable differential transformer with a demonstrated noise floor of {1}{ × 10^{-11}}textrm { m}/sqrt{textrm {Hz}}. We describe the instrument construction and demonstrate low noise operation with a noise floor upper bound of {5.7}{ × 10^{-9}}textrm { rad}/sqrt{textrm {Hz}} at 10 mHz and {6.4}{ × 10^{-10}}textrm { rad}/sqrt{textrm {Hz}} at 0.1 Hz. The performance of the knife edge hinge is compatible with a behaviorur free of noise from dislocation self-organized criticality.

  19. HIGH-PRECISION DYNAMICAL MASSES OF VERY LOW MASS BINARIES

    SciTech Connect

    Konopacky, Q. M.; Ghez, A. M.; McLean, I. S.; Barman, T. S.; Rice, E. L.; Bailey, J. I.; White, R. J.; Duchene, G. E-mail: ghez@astro.ucla.ed E-mail: barman@lowell.ed E-mail: white@chara.gsu.ed

    2010-03-10

    We present the results of a three year monitoring program of a sample of very low mass (VLM) field binaries using both astrometric and spectroscopic data obtained in conjunction with the laser guide star adaptive optics system on the W. M. Keck II 10 m telescope. Among the 24 systems studied, 15 have undergone sufficient orbital motion, allowing us to derive their relative orbital parameters and hence their total system mass. These measurements more than double the number of mass measurements for VLM objects, and include the most precise mass measurement to date (<2%). Among the 11 systems with both astrometric and spectroscopic measurements, six have sufficient radial velocity variations to allow us to obtain individual component masses. This is the first derivation of the component masses for five of these systems. Altogether, the orbital solutions of these low mass systems show a correlation between eccentricity and orbital period, consistent with their higher mass counterparts. In our primary analysis, we find that there are systematic discrepancies between our dynamical mass measurements and the predictions of theoretical evolutionary models (TUCSON and LYON) with both models either underpredicting or overpredicting the most precisely determined dynamical masses. These discrepancies are a function of spectral type, with late-M through mid-L systems tending to have their masses underpredicted, while one T-type system has its mass overpredicted. These discrepancies imply that either the temperatures predicted by evolutionary and atmosphere models are inconsistent for an object of a given mass, or the mass-radius relationship or cooling timescales predicted by the evolutionary models are incorrect. If these spectral-type trends are correct and hold into the planetary mass regime, the implication is that the masses of directly imaged extrasolar planets are overpredicted by the evolutionary models.

  20. Study on manufacturing method of optical surface with high precision in angle and surface

    NASA Astrophysics Data System (ADS)

    Yu, Xin; Li, Xin; Yu, Ze; Zhao, Bin; Zhang, Xuebin; Sun, Lipeng; Tong, Yi

    2016-10-01

    This paper studied a manufacturing processing of optical surface with high precision in angel and surface. By theoretical analysis of the relationships between the angel precision and surface, the measurement conversion of the technical indicators, optical-cement method application, the optical-cement tooling design, the experiment has been finished successfully, the processing method has been verified, which can be also used in the manufacturing of the optical surface with similar high precision in angle and surface.

  1. High precision (14 bit), high density (octal) analog to digital converter for spectroscopy applications

    NASA Astrophysics Data System (ADS)

    Subramaniam, E. T.; Jain, Mamta; Bhowmik, R. K.; Tripon, Michel

    2008-10-01

    Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2″×0.51″) and exhibiting excellent integral nonlinearity (≤±2 mV or ±0.02% full scale reading) and differential nonlinearity (≤±1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance.

  2. High precision (14 bit), high density (octal) analog to digital converter for spectroscopy applications.

    PubMed

    Subramaniam, E T; Jain, Mamta; Bhowmik, R K; Tripon, Michel

    2008-10-01

    Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2(")x0.51(")) and exhibiting excellent integral nonlinearity (< or = +/-2 mV or +/-0.02% full scale reading) and differential nonlinearity (< or = +/-1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance.

  3. Evaluation of a Metric Camera System Tailored for High Precision Uav Applications

    NASA Astrophysics Data System (ADS)

    Kraft, T.; Geßner, M.; Meißner, H.; Cramer, M.; Gerke, M.; Przybilla, H. J.

    2016-06-01

    In this paper we present the further evaluation of DLR's modular airborne camera system MACS-Micro for small unmanned aerial vehicle (UAV). The main focus is on standardized calibration procedures and on photogrammetric workflows. The current prototype consists of an industrial grade frame imaging camera with 12 megapixel resolutions and a compact GNSS/IMU solution which are operated by an embedded computing unit (CPU). The camera was calibrated once pre-flight and several times post-flight over a period of 5 month using a three dimensional test field. The verification of the radiometric quality of the acquired images has been done under controlled static conditions and kinematic conditions testing different demosaicing methods. The validation of MACS-Micro is done by comparing a traditional photogrammetric evaluation with the workflows of Agisoft Photoscan and Pix4D Mapper. The analyses are based on an aerial survey of an urban environment using precise ground control points and acquired GNSS observations. Aerial triangulations with different configuratrions of ground control points (GCP's) had been calculated, comparing the results of using a camera self-calibration and introducing fixed interior orientation parameters for Agisoft and Pix4D. The results are promising concerning the metric characteristics of the used camera and achieved accuracies in this test case. Further aspects have to be evaluated by further expanded test scenarios.

  4. High-precision atomic structure measurements in thallium

    NASA Astrophysics Data System (ADS)

    Burkhardt, M. H.; Holmes, C. D.; Uhl, R.; Majumder, P. K.

    2004-05-01

    Using a thallium atomic beam apparatus, we are undertaking a series of laser spectroscopy measurements with the goal of providing precise, independent cross-checks on the accuracy of new calculations of parity nonconservation in thallium(M. Kozlov et al.), Phys Rev. A64, 053107 (2001). In our apparatus, a laser beam interacts transversely with a dense, 2-cm-wide thallium beam and reveals roughly tenfold Doppler narrowing of the absorption profile. Having completed a new 0.4% measurement of the Stark shift within the 378 nm 6P_1/2-7S_1/2 E1 transition, we have now begun to study the weak 1283 nm 6P_1/2-6P_3/2 transition in the atomic beam. We seek to determine both Stark shift components, as well as the various components of the Stark-induced amplitude within this mixed M1/E2 transition. Using these existing laser systems, we have also begun a vapor cell spectroscopy study of the 1301 nm 7S_1/2-7P_1/2 E1 transition by means of a two-step excitation from the ground state. To enhance the visibility of these weak absorption signals, we are employing an FM spectroscopy technique. The demodulated laser transmission spectrum provides a low-noise, zero-background signal, and includes replicas of the absorption spectrum separated by the well-known RF sideband frequency, offering built-in frequency scale calibration.

  5. High-Precision Nucleation Rate Measurements for Higher Melting Metals

    NASA Astrophysics Data System (ADS)

    Bokeloh, Joachim; Wilde, Gerhard

    2014-08-01

    Nucleation of a crystal in undercooled melts of higher melting face-centered-cubic-metals has often been studied in the past. However, the data available were not of sufficient accuracy and only covered nucleation rates in too small of a range to allow precise conclusions concerning the nature of the underlying process as well as concerning important parameters such as the solid-liquid interface free energy that can in principle be deducted from such analyses. One way to circumvent ambiguities and analyze nucleation kinetics under well-defined conditions experimentally is given by performing statistically significant numbers of repeated single droplet experiments. Application of proper statistics analyses yields nucleation rates that are independent of a specific nucleation model. The first studies that were conducted in accordance with this approach on pure model materials revealed that the approach is valid. The results are comparable to those obtained by classic nucleation theory applied to experimental data, and it was shown that one might need to rethink the common assumption that heterogeneous nucleation is almost always responsible for solidification initiation. The current results also show that often-used models for the solid-liquid interface free energy might lead to overestimated values.

  6. High Performance and Increased Precision Techniques for Feynman Loop Integrals

    NASA Astrophysics Data System (ADS)

    Kato, K.; de Doncker, E.; Ishikawa, T.; Kapenga, J.; Olagbemi, O.; Yuasa, F.

    2016-10-01

    For the investigation of physics within and beyond the Standard Model, a precise evaluation of higher order corrections in perturbative quantum field theory is required. We have worked on the development of a computational method for Feynman loop integrals with a fully numerical approach. It is based on numerical integration and extrapolation techniques. In this paper, we describe the status and new developments in our techniques for the numerical computation of Feynman loop integrals. Separation of ultra-violet divergences is important for the renormalization procedure. In our analyses, the separation can be done numerically. For 2-loop integrals we have performed the calculations for up to 4-point functions, and for 2-point functions we can handle up to 4- loop integrals. We report the status and accuracy of the computations with detailed numerical comparisons to results in the literature, in order to demonstrate that our method will evolve into an important component of automated systems for the study of higher-order radiative corrections.

  7. High Precision Photometry of Bright Transiting Exoplanet Hosts

    NASA Astrophysics Data System (ADS)

    Wilson, Maurice; Eastman, Jason; Johnson, John A.

    2016-01-01

    Within the past two decades, the successful search for exoplanets and the characterization of their physical properties have shown the immense progress that has been made towards finding planets with characteristics similar to Earth. For most exoplanets with a radius about the size of Earth, evaluating their physical properties, such as the mass, radius and equilibrium temperature, cannot be determined with satisfactory precision. The MINiature Exoplanet Radial Velocity Array (MINERVA) was recently built to obtain spectroscopic and photometric measurements to find, confirm, and characterize Earth-like exoplanets. MINERVA's spectroscopic survey targets the brightest, nearby stars which are well-suited to the array's capabilities, while its primary photometric goal is to search for transits around these bright targets. Typically, it is difficult to find satisfactory comparison stars within a telescope's field of view when the primary target is very bright. This issue is resolved by using one of MINERVA's telescopes to observe the primary bright star while the other telescopes observe a distinct field of view that contains satisfactory bright comparison stars. We describe the code used to identify nearby comparison stars, schedule the four telescopes, produce differential photometry from multiple telescopes, and show the first results from this effort.This work has been funded by the Ronald E. McNair Post-Baccalaureate Achievement Program, the ERAU Honors Program, the ERAU Undergraduate Research Spark Fund, and the Banneker Institute at the Harvard-Smithsonian Center for Astrophysics.

  8. High precision silicon piezo resistive SMART pressure sensor

    NASA Astrophysics Data System (ADS)

    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.

  9. Design of a high-precision β-telescope

    NASA Astrophysics Data System (ADS)

    Terbeek, R. H.; Behling, S.; Melconian, D.

    2009-10-01

    The question is raised of whether or not parity is maximally violated in the weak interaction, focusing on β decay. Efforts to measure the neutrino asymmetry parameter, Bν, and how it will provide limits on the existence of a new right-handed W boson are described. In this experiment, a magneto-optical trap is used to laser-cool and confine ^37K atoms, which are then polarized using optical pumping techniques. A β-telescope will be used to detect the energy and direction of the e^+s emitted from the decay. This detector will be used in coincidence with a microchannel plate which observes the momentum of the recoiling ^37Ar nucleus. The kinematics of the decay allow us to deduce the neutrino's momentum event-by-event, and so by correlating the neutrino's momentum with the initial nuclear spin, we will be able to make a precision measurement of Bν. The physics of positron detection and constraints on β-telescope design are covered in detail, as well as research into computer simulation methods for the analysis of response functions and the optimization of certain parameters of a β-telescope.

  10. High-speed precision weighing of pharmaceutical capsules

    NASA Astrophysics Data System (ADS)

    Bürmen, Miran; Pernuš, Franjo; Likar, Boštjan

    2009-11-01

    In this paper, we present a cost-effective method for fast and accurate in-line weighing of hard gelatin capsules based on the optimized capacitance sensor and real-time processing of the capsule capacitance profile resulting from 5000 capacitance measurements per second. First, the effect of the shape and size of the capacitive sensor on the sensitivity and stability of the measurements was investigated in order to optimize the performance of the system. The method was tested on two types of hard gelatin capsules weighing from 50 mg to 650 mg. The results showed that the capacitance profile was exceptionally well correlated with the capsule weight with the correlation coefficient exceeding 0.999. The mean precision of the measurements was in the range from 1 mg to 3 mg, depending on the size of the capsule and was significantly lower than the 5% weight tolerances usually used by the pharmaceutical industry. Therefore, the method was found feasible for weighing pharmaceutical hard gelatin capsules as long as certain conditions are met regarding the capsule fill properties and environment stability. The proposed measurement system can be calibrated by using only two or three sets of capsules with known weight. However, for most applications it is sufficient to use only empty and nominally filled capsules for calibration. Finally, a practical application of the proposed method showed that a single system is capable of weighing around 75 000 capsules per hour, while using multiple systems could easily increase the inspection rate to meet almost any requirements.

  11. High-precision timeline for Earth's most severe extinction.

    PubMed

    Burgess, Seth D; Bowring, Samuel; Shen, Shu-zhong

    2014-03-04

    The end-Permian mass extinction was the most severe loss of marine and terrestrial biota in the last 542 My. Understanding its cause and the controls on extinction/recovery dynamics depends on an accurate and precise age model. U-Pb zircon dates for five volcanic ash beds from the Global Stratotype Section and Point for the Permian-Triassic boundary at Meishan, China, define an age model for the extinction and allow exploration of the links between global environmental perturbation, carbon cycle disruption, mass extinction, and recovery at millennial timescales. The extinction occurred between 251.941 ± 0.037 and 251.880 ± 0.031 Mya, an interval of 60 ± 48 ka. Onset of a major reorganization of the carbon cycle immediately precedes the initiation of extinction and is punctuated by a sharp (3‰), short-lived negative spike in the isotopic composition of carbonate carbon. Carbon cycle volatility persists for ∼500 ka before a return to near preextinction values. Decamillenial to millennial level resolution of the mass extinction and its aftermath will permit a refined evaluation of the relative roles of rate-dependent processes contributing to the extinction, allowing insight into postextinction ecosystem expansion, and establish an accurate time point for evaluating the plausibility of trigger and kill mechanisms.

  12. Application of GPS in a high precision engineering survey network

    SciTech Connect

    Ruland, R.; Leick, A.

    1985-04-01

    A GPS satellite survey was carried out with the Macrometer to support construction at the Stanford Linear Accelerator Center (SLAC). The network consists of 16 stations of which 9 stations were part of the Macrometer network. The horizontal and vertical accuracy of the GPS survey is estimated to be 1 to 2 mm and 2 to 3 mm respectively. The horizontal accuracy of the terrestrial survey, consisting of angles and distances, equals that of the GPS survey only in the ''loop'' portion of the network. All stations are part of a precise level network. The ellipsoidal heights obtained from the GPS survey and the orthometric heights of the level network are used to compute geoid undulations. A geoid profile along the linac was computed by the National Geodetic Survey in 1963. This profile agreed with the observed geoid within the standard deviation of the GPS survey. Angles and distances were adjusted together (TERRA), and all terrestrial observations were combined with the GPS vector observations in a combination adjustment (COMB). A comparison of COMB and TERRA revealed systematic errors in the terrestrial solution. A scale factor of 1.5 ppM +- .8 ppM was estimated. This value is of the same magnitude as the over-all horizontal accuracy of both networks. 10 refs., 3 figs., 5 tabs.

  13. Radiometric surveys in underground environment

    NASA Astrophysics Data System (ADS)

    Bochiolo, Massimo; Chiozzi, Paolo; Verdoya, Massimo; Pasquale, Vincenzo

    2010-05-01

    Due to their ability to travel through the air for several metres, gamma-rays emitted from natural radioactive elements can be successfully used in surveys carried out both with airborne and ground equipments. Besides the concentration of the radio-elements contained in rocks and soils and the intrinsic characteristics of the gamma-ray detector, the detected count rate depends on the solid angle around the spectrometer. On a flat outcrop, ground spectrometry detects the radiation ideally produced by a cylindrical mass of rock of about two metres in diameter and thickness of about half a meter. Under these geometrical conditions, the natural radioactivity can be easily evaluated. With operating conditions different from the standard ones, such as at the edge of an escarpment, the count rate halves because of the missing material, whereas in the vicinity of a rock wall the count rate will increase. In underground environment, the recorded count rate may even double and the in situ assessment of the concentration of radio-elements may be rather difficult, even if the ratios between the different radio-elements may not be affected. We tested the applicability of gamma-ray spectrometry for rapid assessment of the potential hazard levels related to radon and radiation dose rate in underground environment. A mine shaft, located in a zone of uranium enrichment in Liguria (Italy), has been investigated. A preliminary ground radiometric survey was carried out to define the extent of the ore deposit. Then, the radiometric investigation was focussed on the mine shaft. Due to rock mass above the shaft vault, the background gamma radiation can be considered of negligible influence on measurements. In underground surveys, besides deviations from a flat geometry, factors controlling radon exhalation, emanation and stagnation, such as fractures, water leakage and the presence of ventilation, should be carefully examined. We attempted to evaluate these control factors and collected

  14. New linear piezomotors for high-force precise positioning applications

    NASA Astrophysics Data System (ADS)

    Le Letty, Ronan; Claeyssen, Frank; Barillot, Francois; Six, Marc F.; Bouchilloux, Philippe

    1998-07-01

    Piezomotors are an increasingly competitive alternative to electromagnetic stepper motors, especially in applications where large bandwidths and/or precise positioning control are desired. Piezomotors use a combination of electromechanical and frictional forces and, compared to conventional electromagnetic motors, have the advantages that no power supply is required to maintain the motor in position and no lubrication is necessary in the device. The operating principle of these motors relies on the use of an ultrasonic vibration, which is created via the piezoelectric effect (at resonance in most cases), in order to generate vibration forces at the `stator/rotor' contact interface. A mechanical preload is also applied at this contact interface and is responsible for the motor's holding force at rest. To meet the specifications of an aerospace application, we developed a new design of Linear PiezoMotors (LPMs). The first prototype we built shows very promising results, and makes the LPM a serious candidate to replace conventional stepper motors. The LPM features the following characteristics: a standing force of 100 N, a blocked force of 37 N, a maximum actuation speed of 23 mm/s, a maximum run of 10 mm, a mass of 500 g, an electrical power of 2.2 W, and a position accuracy superior to 1 micrometers . To our knowledge, the driving force delivered by the LPM has never before been achieved in resonant devices. This paper describes the physical operating principles of the LPM, as well as the modeling tools and experimental techniques we used for its development. Several implementation schemes are also presented and show the wide range of possible applications offered by the linear piezomotor.

  15. High-precision structure fabrication based on an etching resistance layer

    NASA Astrophysics Data System (ADS)

    Zhang, Man; Deng, Qiling; Shi, Lifang; Cao, Axiu; Pang, Hui; Liu, Xin; Wang, Jiazhou; Hu, Song

    2016-10-01

    The high-precision fabrication of micro-/nano-structure is a challenge. In this paper, we proposed a new fabrication method of high-precision structure based on an etching resistance layer. The high-precision features were fabricated by photolithography technique, followed by the etching process to transfer the features to the substrate. During this process, the etching uniformity and error lead to the feature distortion. We introduced an etching resistance layer between feature layer and substrate. The etching process will stop when arriving at the resistance layer. Due to the high precision of the plating film, the high-precision structure depth was achieved. In our experiment, we introduced aluminum trioxide as the etching resistance layer. The structures with low depth error of less than 5% were fabricated.

  16. Design and development of a high-precision, high-payload telescope dual-drive system

    NASA Astrophysics Data System (ADS)

    Worthington, Michael S.; Beets, Timothy A.; Beno, Joseph H.; Mock, Jason R.; Murphy, Brian T.; South, Brian J.; Good, John M.

    2010-07-01

    A high precision, dual drive system has been designed and developed for the Wide Field Upgrade to the Hobby-Eberly Telescope* at McDonald Observatory in support of the Hobby-Eberly Telescope Dark Energy Experiment‡. Analysis, design and controls details will be of interest to designers of large scale, high precision robotic motion devices. The drive system positions the 19,000 kg star tracker to a precision of less than 5 microns along its 4-meter travel. While positioning requirements remain essentially equal to the existing HET, tracker mass increases by a factor greater than 5. The 10.5-meter long tracker is driven at each end by planetary roller screws, each having two distinct drive sources dictated by the desired operation: one slowly rotates the screw when tracking celestial objects and the second rotates the nut for rapid displacements. Key results of the roller screw rotordynamics analysis are presented. A description of the complex bearing arrangement providing required degrees of freedom as well as the impact of a detailed Failure Modes and Effects Analysis addressing necessary safety systems is also presented. Finite element analysis results demonstrate how mechanical springs increase the telescope's natural frequency response by 22 percent. The critical analysis and resulting design is provided.

  17. A novel power source for high-precision, highly efficient micro w-EDM

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Chen, Chi-Hung

    2015-07-01

    The study presents the development of a novel power source for high-precision, highly efficient machining of micropart microstructures using micro wire electrical discharge machining (w-EDM). A novel power source based on a pluri resistance-capacitance (pRC) circuit that can generate a high-frequency, high-peak current with a short pulse train is proposed and designed to enhance the performance of micro w-EDM processes. Switching between transistors is precisely controlled in the designed power source to create a high-frequency short-pulse train current. Various microslot cutting tests in both aluminum and copper alloys are conducted. Experimental results demonstrate that the pRC power source creates instant spark erosion resulting in markedly less material for removal, diminishing discharge crater size, and consequently an improved surface finish. A new evaluation approach for spark erosion ability (SEA) to assess the merits of micro EDM power sources is also proposed. In addition to increasing the speed of micro w-EDM by increasing wire feed rates by 1.6 times the original feed rate, the power source is more appropriate for machining micropart microstructures since there is less thermal breaking. Satisfactory cutting of an elaborate miniature hook-shaped structure and a high-aspect ratio microstructure with a squared-pillar array also reveal that the developed pRC power source is effective, and should be very useful in the manufacture of intricate microparts.

  18. Moon Mineral Mapper (M3): A High Uniformity and High Precision Science Imaging Spectrometer in the Solar Reflected Spectrum

    NASA Technical Reports Server (NTRS)

    Green, Robert O.; Pieters, Carle; Mouroulis, Pantazis

    2006-01-01

    The Moon Mineralogy Mapper was selected as a NASA Discovery Mission of Opportunity in February 2005. At the core of this mission is an imaging spectrometer instrument with high spectral-spatial uniformity and high signal-to-noise ratio for the expected illumination conditions. The spectral range of the Moon Mineralogy Mapper is from 430 to 3000 nm with 10 nm spectral sampling. The radiometric range is from 0 to maximum expected radiance with 14 bit sampling. The spatial swath is nominally 40 Ian with 70 m spatial sampling. The Moon Mineralogy Mapper has both a global and target mode of data acquisition. In global spectral and spatial resolution full coverage of the Moon will be acquired. Target mode will be used to examine selected areas a full spectral and spatial resolution. The science objectives and mission and instrument characteristics are presented.

  19. Airborne microwave radiometric imaging system

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Li, Futang; Zhang, Zuyin

    1999-09-01

    A dual channel Airborne Microwave Radiometric Imaging system (AMRI) was designed and constructed for regional environment mapping. The system operates at 35GHz, which collects radiation at horizontal and vertical polarized channels. It runs at mechanical conical scanning with 45 degrees incidence angle. Two Cassegrain antennas with 1.5 degrees beamwidth scan the scene alternately and two pseudo- color images of two channels are displayed on the screen of PC in real time. Simultaneously, all parameters of flight and radiometric data are sorted in hard disk for post- processing. The sensitivity of the radiometer (Delta) T equals 0.16K. A new displaying method, unequal size element arc displaying method, is used in image displaying. Several experiments on mobile tower were carried out and the images demonstrate that the AMRI is available to work steadily and accurately.

  20. Optical Imaging and Radiometric Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Ha, Kong Q.; Fitzmaurice, Michael W.; Moiser, Gary E.; Howard, Joseph M.; Le, Chi M.

    2010-01-01

    OPTOOL software is a general-purpose optical systems analysis tool that was developed to offer a solution to problems associated with computational programs written for the James Webb Space Telescope optical system. It integrates existing routines into coherent processes, and provides a structure with reusable capabilities that allow additional processes to be quickly developed and integrated. It has an extensive graphical user interface, which makes the tool more intuitive and friendly. OPTOOL is implemented using MATLAB with a Fourier optics-based approach for point spread function (PSF) calculations. It features parametric and Monte Carlo simulation capabilities, and uses a direct integration calculation to permit high spatial sampling of the PSF. Exit pupil optical path difference (OPD) maps can be generated using combinations of Zernike polynomials or shaped power spectral densities. The graphical user interface allows rapid creation of arbitrary pupil geometries, and entry of all other modeling parameters to support basic imaging and radiometric analyses. OPTOOL provides the capability to generate wavefront-error (WFE) maps for arbitrary grid sizes. These maps are 2D arrays containing digital sampled versions of functions ranging from Zernike polynomials to combination of sinusoidal wave functions in 2D, to functions generated from a spatial frequency power spectral distribution (PSD). It also can generate optical transfer functions (OTFs), which are incorporated into the PSF calculation. The user can specify radiometrics for the target and sky background, and key performance parameters for the instrument s focal plane array (FPA). This radiometric and detector model setup is fairly extensive, and includes parameters such as zodiacal background, thermal emission noise, read noise, and dark current. The setup also includes target spectral energy distribution as a function of wavelength for polychromatic sources, detector pixel size, and the FPA s charge

  1. HYDRA: High Speed Simulation Architecture for Precision Spacecraft Formation Flying

    NASA Technical Reports Server (NTRS)

    Martin, Bryan J.; Sohl, Garett A.

    2003-01-01

    This viewgraph presentation describes HYDRA, which is architecture to facilitate high-fidelity and real-time simulation of formation flying missions. The contents include: 1) Motivation; 2) Objective; 3) HYDRA-Description and Overview; 4) HYDRA-Hierarchy; 5) Communication in HYDRA; 6) Simulation Specific Concerns in HYDRA; 7) Example application (Formation Acquisition); and 8) Sample Problem Results.

  2. Pointing Control System for a High Precision Flight Telescope

    SciTech Connect

    BENTLEY,ANTHONY E.; WILCOXEN,JEFFREY LEE

    2000-12-01

    A pointing control system is developed and tested for a flying gimbaled telescope. The two-axis pointing system is capable of sub-microradian pointing stability and high accuracy in the presence of large host vehicle jitter. The telescope also has high agility--it is capable of a 50-degree retarget (in both axes simultaneously) in less than 2 seconds. To achieve the design specifications, high-accuracy, high-resolution, two-speed resolvers were used, resulting in gimbal-angle measurements stable to 1.5 microradians. In addition, on-axis inertial angle displacement sensors were mounted on the telescope to provide host-vehicle jitter cancellation. The inertial angle sensors are accurate to about 100 nanoradians, but do not measure low frequency displacements below 2 Hz. The gimbal command signal includes host-vehicle attitude information, which is band-limited. This provides jitter data below 20 Hz, but includes a variable latency between 15 and 25 milliseconds. One of the most challenging aspects of this design was to combine the inertial-angle-sensor data with the less perfect information in the command signal to achieve maximum jitter reduction. The optimum blending of these two signals, along with the feedback compensation were designed using Quantitative Feedback Theory.

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

    PubMed

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Huang, Youping; Towers, David Peter

    2016-12-30

    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.

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

    PubMed Central

    Huang, Junhui; Wang, Zhao; Gao, Jianmin; Huang, Youping; Towers, David Peter

    2016-01-01

    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. PMID:28042846

  5. Coating-free mirrors for high precision interferometric experiments

    SciTech Connect

    Gossler, Stefan; Cumpston, Jeff; McKenzie, Kirk; Mow-Lowry, Conor M.; Gray, Malcolm B.; McClelland, David E.

    2007-11-15

    Thermal noise in mirror optical coatings may not only limit the sensitivity of future gravitational-wave detectors in their most sensitive frequency band but is also a major impediment for experiments that aim to reach the standard quantum limit or cool mechanical systems to their quantum ground state. We present the design and experimental characterization of a highly reflecting mirror without any optical coating. This coating-free mirror is based on total internal reflection and Brewster-angle coupling. In order to characterize its performance, the coating-free mirror was incorporated into a triangular ring cavity together with a high quality conventional mirror. The finesse of this cavity was measured using an amplitude transfer function to be about F{approx_equal}4000. This finesse corresponds to a reflectivity of the coating-free mirror of about R{approx_equal}99.89%. In addition, the dependence of the reflectivity on rotation was mapped out.

  6. High speed precision motion strategies for lightweight structures

    NASA Technical Reports Server (NTRS)

    Book, Wayne J.

    1987-01-01

    Work during the recording period proceeded along the lines of the proposal, i.e., three aspects of high speed motion planning and control of flexible structures were explored: fine motion control, gross motion planning and control, and automation using light weight arms. In addition, modeling the large manipulator arm to be used in experiments and theory has lead to some contributions in that area. These aspects are reported below. Conference, workshop and journal submissions, and presentations related to this work were seven in number, and are listed. Copies of written papers and abstracts are included.

  7. Spectral band passes for a high precision satellite sounder

    NASA Technical Reports Server (NTRS)

    Kaplan, L. D.; Chahine, M. T.; Susskind, J.; Searl, J. E.

    1977-01-01

    Atmospheric temperature soundings with significantly improved vertical resolution can be obtained from carefully chosen narrow band-pass measurements in the 4.3-micron band of CO2 by taking advantage of the variation of the absorption coefficients, and thereby the weighting functions, with pressure and temperature. A set of channels has been found in the 4.2-micron region that is capable of yielding about 2-km vertical resolution in the troposphere. The concept of a complete system is presented for obtaining high resolution retrievals of temperature and water vapor distribution, as well as surface and cloud top temperatures, even in the presence of broken clouds.

  8. Combination spindle-drive system for high precision machining

    DOEpatents

    Gerth, Howard L.

    1977-07-26

    A combination spindle-drive is provided for fabrication of optical quality surface finishes. Both the spindle-and-drive utilize the spindle bearings for support, thereby removing the conventional drive-means bearings as a source of vibration. An airbearing spindle is modified to carry at the drive end a highly conductive cup-shaped rotor which is aligned with a stationary stator to produce torque in the cup-shaped rotor through the reaction of eddy currents induced in the rotor. This arrangement eliminates magnetic attraction forces and all force is in the form of torque on the cup-shaped rotor.

  9. Decentralized high precision telemetry and telecommand system for sounding rockets

    NASA Astrophysics Data System (ADS)

    Heyer, Heinz-Volker; Schmitt, Günter; Pfeuffer, Horst; Voss, Bernhard

    2005-08-01

    TEXUS and MAXUS payloads are currently providing 12 bit analog channel accuracy for their data acquisition chains with different signal conditioning elements such as temperature measurement, strain gauge, pressure measurement channels, and general purpose amplifiers. Transient recording functions are rather seldom as all data is directly transmitted via PCM to the ground station. However, the user requirements are steadily increasing in terms of accuracy, data security, and high data throughput rate with an ever increasing number of telemetry channels. The newly developed Kayser-Threde telemetry and telecommand system CTS 3000 (Compact Telemetry System) fulfils these requirements by providing up to 16 bit accuracy for its analog channels with a sampling rate up to 2 kHz (at this accuracy), on-board transient memory to protect against data loss and provides an integrated telecommand decoder at the same time, reducing the necessary amount of equipment used for instrumentation. The equipment further reduces the necessary effort for refurbishment because of its internal self calibration over the full environment temperature range. On top of its IRIG PCM interface the system is equipped with a USB bus, a well-known and commonly used PC standard high performance interface. This interface is used for configuration, testing, and monitoring of the CTS 3000 providing a simple and easy to use user environment for the new equipment. The paper will introduce the new equipment and will show the application in the TEXUS/MAXUS project.

  10. High precision moving magnet chopper for variable operation conditions

    NASA Technical Reports Server (NTRS)

    Aicher, Winfried; Schmid, Manfred

    1994-01-01

    In the context of an ESTEC technology contract, a Chopping Mechanism was developed and built with the Far Infrared and Submillimeter Telescope (FIRST) astronomy mission as a reference. The task of the mechanism is to tilt the subreflector of the telescope with an assumed mass of 2.5 kg about one chopping axis at nominal frequencies of up to 5 Hz and chopping angles of up to +/- 11.25 mrad with high efficiency (minimum time for position change). The chopping axis is required to run through the subreflector vertex. After performing a concept trade-off also considering the low operational temperatures in the 130 K range, a design using moving magnet actuators was found to be the favorite one. In addition, a bearing concept using flexible pivots was chosen to meet the high chopping accuracy required. With this approach, a very reliable design could be realized, since the actuators work without any mechanical contact between its moving and fixed parts, and the only bearings used are two flexible pivots supporting the subreflector mounting interface. The mechanism was completely built in titanium in a lightweight and stiff design. The moving magnet actuators were designed to meet the stringent requirements for minimum risetime (time necessary to move from one angular position to a new one) in the 20 msec range. The angular position and the corresponding chopping frequency as well can be arbitrarily selected by the user.

  11. Unraveling high precision stereocontrol in a triple cascade organocatalytic reaction.

    PubMed

    Shinisha, C B; Sunoj, Raghavan B

    2008-11-07

    The mechanism and stereoselectivity in an organocatalyzed triple cascade reaction between an aldehyde, electron deficient olefin and an alpha,beta-unsaturated aldehyde are investigated for the first time using density functional theory. The factors responsible for high levels of observed stereoselectivity (Enders et al., Nature, 2006, 441, 861) towards the generation of cyclohexene carbaldehyde with four contiguous stereocentres are unravelled. The triple cascade reaction, comprising a Michael, Michael and aldol sequence as the key elementary reactions, is studied by identifying the corresponding transition states for the stereoselective C-C bond-formation. In the first Michael addition step between the enamine (derived from the chiral catalyst and propanal) and nitrostyrene, energetically the most preferred mode of addition is found to be between the si-face of (E)-anti-enamine on the si-face of nitrostyrene. The addition of the si-face of the nitroalkane anion on the re-face of the iminium ion (formed between the enal and the catalyst) is the lowest energy pathway for the second Michael addition step. The high level of asymmetric induction is rationalized with the help of relative activation barriers associated with the competitive diastereomeric pathways. Interesting weak interactions, along with the steric effects offered by the bulky alpha-substituent on the pyrrolidine ring, are identified as critical to the stereoselectivity in this triple cascade reaction. The predicted stereoselectivities using computed energetics are found to be in perfect harmony with the experimental stereoselectivities.

  12. High integrity GPS/INS filter for precise relative navigation

    NASA Astrophysics Data System (ADS)

    Abdel-Hafez, Mamoun F.

    A GPS/INS filter design for absolute and relative state estimation is discussed. The GPS code and Doppler measurements are used for absolute state estimation while the GPS carrier phase and Doppler measurements are used for relative state estimation. Real-time results obtained from a Hardware-in-the-Loop Simulation and actual F-18 flight tests are presented. To ensure accurate state estimation, the observability of the GPS/INS system is analyzed analytically when the system is at rest and during maneuvers. The system observability enhancement during two different maneuvers is discussed. Simulation results illustrating the observability of the system during the different stages of the GPS/INS system operation are also presented. To allow successful use of the high-accuracy carrier phase measurements, two methods for resolving GPS integer ambiguity are introduced. The first combines an efficient method for obtaining the admissible integer ambiguity hypotheses within a probabilistic volume with an integer hypothesis testing method to reduce the convergence time with high probability to the GPS carrier phase integers. The second GPS integer ambiguity resolution method is based on a log-formulation of the Multiple Hypothesis Wald Sequential Probability Test (MHWSPT). The computational time requirement of the latter method is shown to be smaller than the former method. Real-time results are presented to show the performance of the two methods introduced.

  13. High precision, low disturbance calibration system for the CMS Barrel Electromagnetic Calorimeter High Voltage apparatus

    NASA Astrophysics Data System (ADS)

    Fasanella, G.

    2017-01-01

    The CMS Electromagnetic Calorimeter utilizes scintillation 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 3%/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.

  14. High-precision metrology of highly charged ions via relativistic resonance fluorescence.

    PubMed

    Postavaru, O; Harman, Z; Keitel, C H

    2011-01-21

    Resonance fluorescence of laser-driven highly charged ions is investigated with regard to precisely measuring atomic properties. For this purpose an ab initio approach based on the Dirac equation is employed that allows for studying relativistic ions. These systems provide a sensitive means to test correlated relativistic dynamics, quantum electrodynamic phenomena and nuclear effects by applying x-ray lasers. We show how the narrowing of sidebands in the x-ray fluorescence spectrum by interference due to an additional optical driving can be exploited to determine atomic dipole or multipole moments to unprecedented accuracy.

  15. High precision, medium flux rate CZT spectroscopy for coherent scatter imaging

    NASA Astrophysics Data System (ADS)

    Greenberg, Joel A.; Hassan, Mehadi; Brady, David J.; Iniewski, Kris

    2016-05-01

    CZT detectors are primary candidates for many next-generation X-ray imaging systems. These detectors are typically operated in either a high precision, low flux spectroscopy mode or a low precision, high flux photon counting mode. We demonstrate a new detector configuration that enables operation in a high precision, medium flux spectroscopy mode, which opens the potential for a variety of new applications in medical imaging, non-destructive testing and baggage scanning. In particular, we describe the requirements of a coded aperture coherent scattering X-ray system that can perform fast imaging with accurate material discrimination.

  16. Stellar Astrophysics Using Ultra-High Precision CCD Time Series Photometry

    NASA Astrophysics Data System (ADS)

    Howell, S.; Everett, M.; Huber, M.; Ciardi, D.; van Belle, G.

    2001-05-01

    Using time-series CCD photometry and a wide-field imager, we have extended the techniques of differential photometry to provide robust photometric precisions for each star over the entire field of view. Reaching photometric precisions of 2 milli-magnitudes, we produced high cadence light curves for over 12,000 stars at mid- and high galactic latitude. The fraction of stars seen to be variable is higher than the canonical wisdom, being 10-14 will present the details of our techniques, sample light curves, methods to access the data, and a summary of astrophysical uses of such high precision data.

  17. High Precision Assembly of Thin Mirror X-ray Telescopes

    NASA Astrophysics Data System (ADS)

    Schattenburg, Mark

    Lightweight high resolution x-ray telescope optics are one of the key technologies under development for next-generation x-ray telescopes. The ultimate goal of this effort is to realize optics with spatial resolution rivaling Chandra (<1 arc-sec) but with collecting areas that are larger by orders of magnitude. In the USA several institutions, including GSFC, MSFC, Harvard-SAO, MIT and Northwest University are working on a variety of approaches to this problem. An excellent example is the NuSTAR x-ray telescope, which teamed Cal Tech, GSFC, Columbia University and LLNL to produce a superb set of hard x-ray optics. The telescope was composed of thousands of 0.2 mm-thick glass mirrors which were epoxied into place around a spindle structure. While very light weight, this process resulted in ~1 arc min resolution. We want to achieve ~100 times better with similar mass. A group at NASA GSFC has recently demonstrated an alternative thin-glass assembly procedure that has achieved ~7 arc sec resolution with x-ray tests. Further progress towards 1 arc-sec will require mirrors with improved figure, lower stress coatings, improved alignment, better metrology, and low stress bonding. Many of the difficulties with current mirror assembly practice stem from the use of epoxy as a bonding agent. Epoxy has many disadvantages, including high shrinkage, large CTE and creep, resin aging effects, water absorption, outgassing, low tensile strength, exothermicity, and requiring large amounts of time and/or heat to cure. These effects can cause errors that become â€oefrozen in― to the bond with no possibility of correction. We propose to investigate replacing epoxy with low temperature, low shrinkage solder alloys. We use these solders in conjunction with high power, millisec-long pulses from a fiber IR laser to deliver controlled amounts of heat into the bond area. We have demonstrated that laser pulses can be used to actuate carefully designed bonds by permanently compressing

  18. Calibration, registration, and synchronization for high precision augmented reality haptics.

    PubMed

    Harders, Matthias; Bianchi, Gérald; Knoerlein, Benjamin; Székely, Gábor

    2009-01-01

    In our current research we examine the application of visuo-haptic augmented reality setups in medical training. To this end, highly accurate calibration, system stability, and low latency are indispensable prerequisites. These are necessary to maintain user immersion and avoid breaks in presence which potentially diminish the training outcome. In this paper we describe the developed calibration methods for visuo-haptic integration, the hybrid tracking technique for stable alignment of the augmentation, and the distributed framework ensuring low latency and component synchronization. Finally, we outline an early prototype system based on the multimodal augmented reality framework. The latter allows colocated visuo-haptic interaction with real and virtual scene components in a simplified open surgery setting.

  19. High Precision SC Cavity Diagnostics with HOM Measurements

    SciTech Connect

    Frisch, Josef; Hendrickson, Linda; McCormick, Douglas; May, Justin; Molloy, Stephen; Ross, Marc; /SLAC

    2006-08-18

    Experiments at the FLASH linac at DESY have demonstrated that the Higher Order Modes induced in Superconducting Cavities can be used to provide a variety of beam and cavity diagnostics. The centers of the cavities can be determined from the beam orbit which produces minimum power in the dipole HOM modes. The phase and amplitude of the dipole modes can be used as a high resolution beam position monitor, and the phase of the monopole modes to measure the beam phase relative to the accelerator RF. Beam orbit feedback which minimizes the dipole HOM power in a set of structures has been demonstrated. For most SC accelerators, the existing HOM couplers provide the necessary signals, and the down mix and digitizing electronics are straightforward, similar to those for a conventional BPM.

  20. Derivative properties from high-precision equations of state.

    PubMed

    Haghbakhsh, Reza; Konttorp, Morten; Raeissi, Sona; Peters, Cor J; O'Connell, John P

    2014-12-11

    In this study, the behavior of derivative properties estimated by equations of state, including isochoric heat capacity, isobaric heat capacity, speed of sound, and the Joule-Thomson coefficient for pure compounds and a mixture, has been investigated. The Schmidt-Wagner and Jacobsen-Stewart equations of state were used for predictions of derivative properties of 10 different pure compounds from various nonpolar hydrocarbons, nonpolar cyclic hydrocarbons, polar compounds, and refrigerants. The estimations were compared to experimental data. To evaluate the behavior of mixtures, the extended corresponding states principle (ECS) was studied. Analytical relationships were derived for isochoric heat capacity, isobaric heat capacity, the Joule-Thomson coefficient, and the speed of sound. The ECS calculations were compared to the reference surface data of methane + ethane. The ECS principle was found to generate data of high quality.

  1. Development of Large Current High Precision Pulse Power Supply

    NASA Astrophysics Data System (ADS)

    Takayanagi, Tomohiro; Koseki, Shoichiro; Kubo, Hiroshi; Katoh, Shuji; Ogawa, Shinichi

    JAEA and KEK are jointly constructing a high intensity proton accelerator project J-PARC. Its main accelerator is 3GeV synchrotron. Its injection bump magnets, especially horizontal paint bump magnets, are excited by large pulse currents. Their rated currents are over 10kA and pulse widths are about 1ms. Tracking errors are required to be less than 1%. Multiple connected two-quadrant IGBT choppers are adopted for their power supplies. Their output currents are controlled by feedback control with minor loop voltage control (m-AVR). When output current of a chopper intermits at small current, its output voltage rises up and current control becomes difficult. In this paper response of m-AVR and output voltage characteristics at current intermittent region are studied and an improved control scheme is proposed. The performance is confirmed by a test.

  2. Precision high energy liner implosion experiments PHELIX [1

    SciTech Connect

    Reass, William A; Baca, David M; Griego, Jeffrey R; Reinovsky, Robert E; Rousculp, Christopher L; Turchi, Peter J

    2009-01-01

    This paper describes the hardware design of a small megajoule sized transformer coupled pulse power system utilized to drive hydrodynamic liner experiments with a nominal current capability of 10 megAmperes. The resulting liner velocities and characteristics provide properties of physics interest. The capacitor banks utilize the ''Atlas'' plastic cased 60 kV, 60 kJ capacitors [2] and railgaps [3]. The air insulated marx'S are configured to dive a multi-filar toroidal transformer. The 4:1 multi-filar toroidal transformer is mechanically part of a circular disc line and this feature results in an attractive inductance budget. Because of the compact size, re-usable transformer, and resulting low maintenance cost, shot rates can be high compared to other ''large'' machines or explosively driven hydrodynamic methods. The PHELIX modeling, construction status, and test results will also be provided.

  3. A high precision calorimeter for the SOX experiment

    NASA Astrophysics Data System (ADS)

    Papp, L.; Agostini, M.; Altenmüller, K.; Appel, S.; Caminata, A.; Cereseto, R.; Di Noto, L.; Farinon, S.; Musenich, R.; Neumair, B.; Oberauer, L.; Pallavicini, M.; Schönert, S.; Testera, G.; Zavatarelli, S.

    2016-07-01

    The SOX (Short distance neutrino Oscillations with BoreXino) experiment is being built to discover or reject eV-scale sterile neutrinos by observing short baseline oscillations of active-to-sterile neutrinos [1]. For this purpose, a 100 kCi 144Ce-144Pr antineutrino generator (CeSOX) will be placed under the BOREXINO detector at the Laboratori Nazionali del Gran Sasso. Thanks to its large size and very low background, BOREXINO is an ideal detector to discover or reject eV-scale sterile neutrinos. To reach the maximal sensitivity, we aim at determining the neutrino flux emitted by the antineutrino generator with a < 1 % accuracy. With this goal, TU München and INFN Genova are developing a vacuum calorimeter, which is designed to measure the source-generated heat with high accuracy.

  4. High precision pointing with a multiline spectrometer at the VTT

    NASA Astrophysics Data System (ADS)

    Staiger, J.

    2012-12-01

    We are investigating the pointing quality of the VTT, Tenerife under the aspect of suitability for long-term heliosesimological observations. Tests have shown that thermal and mechanical loads within the telescope may create spurious image drifts with shift rates of up to 5 arcsec per hour. During daylong recordings this will reduce significantly the effective size of the field-of-view and may infer artificial lateral movements into the data. The underlying problem that not all image position offsets developing during a measurement may be compensated for is common to most high-resolution solar telescopes independently of the type of pointing system used. We are developing new approaches to address this problem which are to be tested in the near future at the VTT. The simulations established so far show that the problem may be reduced by more than 90 %.

  5. Creating high-stability high-precision bipolar trim power supply

    SciTech Connect

    Chen, Zhe; Merz, William A.

    2012-07-01

    Thomas Jefferson National Accelerator Facility (TJNAF) is founded by the US Department of Energy (DOE) office of science for the technology advancement and physics research in electron beam accelerator. This facility has the state of the art technology to carry out world-class cutting-edge experiments for the nucleus composition and atomic characteristics identification and exploration for the nature of the matter in the universe. A continuous wave electron beam is featured for such experiments, thus precise and stable trim power supply is required to meet such purpose. This paper demonstrates the challenges and solutions to design, assemble, fabrication and test such high-precision high-stability power supplies. This paper presents the novel design and first article test of the ±20A ±75V bipolar, 100ppm stability level current-regulated high-power trim power supplies for the beam manipulation. This special design can provide valuable documentation and reference values for future designs and special applications in particle accelerator power supply creation.

  6. High Precision Ti stable Isotope Measurement of Terrestrial Rocks

    NASA Astrophysics Data System (ADS)

    Millet, M. A.; Dauphas, N.; Williams, H. M.; Burton, K. W.; Nowell, G. M.

    2014-12-01

    Advances in multi-collection plasma source mass spectrometry have allowed the determination of stable isotope composition of transition metals to address questions relevant to both high and low temperature geochemistry. However, titanium has received only very limited attention. Here we present a new technique allowing the determination of the stable isotope composition of titanium in geological samples (d49Ti or deviation of the 49Ti/47Ti ratio from the OL-Ti in-house standard of reference) using double-spike methodology and high-resolution MC-ICP-MS. We have carried out a range analytical tests for a wide spectrum of samples matrices to demonstrate a external reproducibility of ±0.02‰ on the d49Ti while using as little as 150ng of natural Ti for a single analysis. We have analysed a comprehensive selection of mantle-derived samples covering a range of geodynamic contexts (MORB, IAB, OIB, adakites, eclogites, serpentines) and geographical distribution (MORB: Mid-Atlantic Ridge, Southwest Indian Ridge and Eastern Pacific Ridge; IAB: New Britain reference suite and Marianas Arc). The samples show a very limited range from -0.06‰ to +0.04‰ with a main mode at +0.004‰ relative to the OL-Ti standard. Average values for MORB, IAB and eclogites are similar within uncertainty and thus argue for limited mobility of Ti during subduction zone processes and homogeneity of the Ti stable isotope composition of the upper mantle. However, preliminary data for more evolved igneous rocks suggest that they display heavier Ti stable isotope compositions, which may reflect the removal of isotopically light Ti as a function of Fe-Ti oxide crystallisation. This is in good agreement with Ti being present in 5-fold and 6-fold coordination in basaltic melts and preferential uptake of 6-folded Ti by Ti-bearing oxides [1]. This dataset will be complemented by analysis of abyssal peridotites to confirm the homogeneity of the mantle as well as data for a range of ferromanganese crusts

  7. High Resolution Airborne Digital Imagery for Precision Agriculture

    NASA Technical Reports Server (NTRS)

    Herwitz, Stanley R.

    1998-01-01

    The Environmental Research Aircraft and Sensor Technology (ERAST) program is a NASA initiative that seeks to demonstrate the application of cost-effective aircraft and sensor technology to private commercial ventures. In 1997-98, a series of flight-demonstrations and image acquisition efforts were conducted over the Hawaiian Islands using a remotely-piloted solar- powered platform (Pathfinder) and a fixed-wing piloted aircraft (Navajo) equipped with a Kodak DCS450 CIR (color infrared) digital camera. As an ERAST Science Team Member, I defined a set of flight lines over the largest coffee plantation in Hawaii: the Kauai Coffee Company's 4,000 acre Koloa Estate. Past studies have demonstrated the applications of airborne digital imaging to agricultural management. Few studies have examined the usefulness of high resolution airborne multispectral imagery with 10 cm pixel sizes. The Kodak digital camera integrated with ERAST's Airborne Real Time Imaging System (ARTIS) which generated multiband CCD images consisting of 6 x 106 pixel elements. At the designated flight altitude of 1,000 feet over the coffee plantation, pixel size was 10 cm. The study involved the analysis of imagery acquired on 5 March 1998 for the detection of anomalous reflectance values and for the definition of spectral signatures as indicators of tree vigor and treatment effectiveness (e.g., drip irrigation; fertilizer application).

  8. A research of a high precision multichannel data acquisition system

    NASA Astrophysics Data System (ADS)

    Zhong, Ling-na; Tang, Xiao-ping; Yan, Wei

    2013-08-01

    The output signals of the focusing system in lithography are analog. To convert the analog signals into digital ones which are more flexible and stable to process, a desirable data acquisition system is required. The resolution of data acquisition, to some extent, affects the accuracy of focusing. In this article, we first compared performance between the various kinds of analog-to-digital converters (ADC) available on the market at the moment. Combined with the specific requirements (sampling frequency, converting accuracy, numbers of channels etc) and the characteristics (polarization, amplitude range etc) of the analog signals, the model of the ADC to be used as the core chip in our hardware design was determined. On this basis, we chose other chips needed in the hardware circuit that would well match with ADC, then the overall hardware design was obtained. Validation of our data acquisition system was verified through experiments and it can be demonstrated that the system can effectively realize the high resolution conversion of the multi-channel analog signals and give the accurate focusing information in lithography.

  9. High-Precision Measurements of the Brightness Variation of Nereid

    NASA Astrophysics Data System (ADS)

    Terai, Tsuyoshi; Itoh, Yoichi

    2013-04-01

    Nereid, the outer satellite of Neptune, has a highly eccentric prograde orbit with a semimajor axis of larger than 200 in units of Neptune's radius, and is classified as an irregular satellite. Although the capture origin of irregular satellites has been widely accepted, several previous studies suggest that Nereid was formed in the circumplanetary disk of Neptune and ejected outward to the present location by Triton. A series of our photometric observations confirm that Nereid's rotation period, 11.5 hr, is stable and nonchaotic, as indicated by Grav, Holman, and Kavelaars (2003, ApJ, 591, L71). The optical colors of Nereid are indistinguishable from those of trans-Neptunian objects and Centaurs, especially from these objects with neutral colors. We also found the consistency of Nereid's rotation period based on the size-rotation distribution of small outer bodies. It is likely that Nereid originated as an immigrant body captured from the heliocentric orbit that was 4-5 AU away from Neptune's orbit.

  10. High Resolution Airborne Digital Imagery for Precision Agriculture

    NASA Technical Reports Server (NTRS)

    Herwitz, Stanley R.

    1998-01-01

    The Environmental Research Aircraft and Sensor Technology (ERAST) program is a NASA initiative that seeks to demonstrate the application of cost-effective aircraft and sensor technology to private commercial ventures. In 1997-98, a series of flight-demonstrations and image acquisition efforts were conducted over the Hawaiian Islands using a remotely-piloted solar- powered platform (Pathfinder) and a fixed-wing piloted aircraft (Navajo) equipped with a Kodak DCS450 CIR (color infrared) digital camera. As an ERAST Science Team Member, I defined a set of flight lines over the largest coffee plantation in Hawaii: the Kauai Coffee Company's 4,000 acre Koloa Estate. Past studies have demonstrated the applications of airborne digital imaging to agricultural management. Few studies have examined the usefulness of high resolution airborne multispectral imagery with 10 cm pixel sizes. The Kodak digital camera integrated with ERAST's Airborne Real Time Imaging System (ARTIS) which generated multiband CCD images consisting of 6 x 106 pixel elements. At the designated flight altitude of 1,000 feet over the coffee plantation, pixel size was 10 cm. The study involved the analysis of imagery acquired on 5 March 1998 for the detection of anomalous reflectance values and for the definition of spectral signatures as indicators of tree vigor and treatment effectiveness (e.g., drip irrigation; fertilizer application).

  11. High Precision Cosmology with the Cosmic Background Radiation

    NASA Astrophysics Data System (ADS)

    Farhang, Marzieh

    around the fiducial model of the standard recombination scenario. Though theoretically well studied, the detailed assumptions in the recombination history, based on standard atomic physics, have never been directly tested. However, for our CMB-based cosmological inferences to be reliable, the recombination scenario needs to be observationally verified. We approach this problem in a model-independent way and construct rank-ordered parameter eigen-modes with the highest power to probe Xe. We study various properties of these modes, including their convergence, fiducial model-dependence, dataset dependence, and the eigen-modes response to marginalization over different standard parameters. We demonstrate that, if enough modes are included, the eigen-modes form a practically complete set of basis function for expanding different physically motivated Xe perturbations. We also develop an information-based criterion to truncate the eigen-mode hierarchy, which can be used in similar hierarchical model selections as well. We show how our measurements of cosmic parameters will be affected if possible deviations in the recombination history are ignored. The method is applied to simulations of Planck+ACTPol and a cosmic variance limited survey with differing simulated recombination histories and the recovered Xe trajectories are constructed. We also apply the method to the best currently available CMB datasets, WMAP9+ACT/SPT. The first constructed eigen-mode turns out to be a direct measure of the damping envelope. Its current measurement with SPT slightly indicates a damping tail anomaly, while ACT data agree well with the standard scenario. High resolution Planck data will resolve this tension with high significance.

  12. High Precision Pulsar Timing: Effects of ISM Correction Schemes

    NASA Astrophysics Data System (ADS)

    Kunert, Willie; Verbiest, J. P. W.; Shannon, R.; Stinebring, D.

    2012-01-01

    Pulsar timing arrays are one of the leading methods in the search for gravitational waves (GWs). However a significant issue facing this method is the effect of the interstellar medium (ISM). There are multiple methodologies being used to correct for these effects but their efficacy has not been carefully studied. We conducted an initial study of biases induced by correcting for the interstellar medium. We simulated times of arrival (TOAs) with white noise and added ISM delays. We measure the ISM effects as is done with normal data, and created a model of these effects using polynomial fitting. This modeling method is most commonly used in the European Pulsar Timing Array. We then remove these measured ISM effects and compare final and initial TOAs. Ideally they should be the same; however, the differences between the 'corrected' TOAs and original TOAs reveal the weaknesses of this method. In preliminary results we concluded that the higher order polynomials do a better job, yet there is a limit as to how high an order one can use. We also found no significant systematic parameter bias induced by using this method. However, it is clear that certain parameters are more affected by this process of correction. The parameters most affected were the frequency and frequency derivative of the pulsar, but biases in these parameters are not important because the power due to them gets removed in the standard timing analysis. We are continuing this research by comparing and contrasting ISM correction schemes, as well as studying the actual behavior of the ISM in more detail. This research is supported by an NSF-PIRE and an NSF-AST grant.

  13. Flexible head-casts for high spatial precision MEG.

    PubMed

    Meyer, Sofie S; Bonaiuto, James; Lim, Mark; Rossiter, Holly; Waters, Sheena; Bradbury, David; Bestmann, Sven; Brookes, Matthew; Callaghan, Martina F; Weiskopf, Nikolaus; Barnes, Gareth R

    2017-01-30

    In combination with magnetoencephalographic (MEG) data, accurate knowledge of the brain's structure and location provide a principled way of reconstructing neural activity with high temporal resolution. However, measuring the brain's location is compromised by head movement during scanning, and by fiducial-based co-registration with magnetic resonance imaging (MRI) data. The uncertainty from these two factors introduces errors into the forward model and limit the spatial resolution of the data. We present a method for stabilizing and reliably repositioning the head during scanning, and for co-registering MRI and MEG data with low error. Using this new flexible and comfortable subject-specific head-cast prototype, we find within-session movements of <0.25mm and between-session repositioning errors around 1mm. This method is an improvement over existing methods for stabilizing the head or correcting for location shifts on- or off-line, which still introduce approximately 5mm of uncertainty at best (Adjamian et al., 2004; Stolk et al., 2013; Whalen et al., 2008). Further, the head-cast design presented here is more comfortable, safer, and easier to use than the earlier 3D printed prototype, and give slightly lower co-registration errors (Troebinger et al., 2014b). We provide an empirical example of how these head-casts impact on source level reproducibility. Employment of the individual flexible head-casts for MEG recordings provide a reliable method of safely stabilizing the head during MEG recordings, and for co-registering MRI anatomical images to MEG functional data. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

  14. Small Scale Landscape Evolution: Rainfall Simulations On High Precision Dtms

    NASA Astrophysics Data System (ADS)

    Catani, F.; Moretti, S.

    Processes characterizing the evolution of relief have recently been recognized as hav- ing scaling properties both in their physical behavior and in their effects on the shape of landscape. Sophisticated evolutionary models have been devised so far, which takes also into account fractal properties, self-similarity and self-organized criticality, espe- cially in the organization of river networks inside catchments. Despite these efforts, which are generally successful from a theoretical point of view, few attempts have been made to actually test these hypotheses in the field. This is due mainly to the dif- ficulties connected with the practical realization of suitable physical models as well as with the problem of the time scale of such processes when dealing with whole river basins. This paper, that presents experimental data on the geometric and morphometric evolution of small scale soil parcels after simulated cycles of rainfall, could contribute to partially fill this gap giving insight on the spatial patterns of newly formed valleys and ridges as well as on the most stable geomorphological configurations. Starting from chosen parcels on crops or bare soils in central Italy, rainfall simulations have been undertaken over repeating cycles of storms. At the beginning of the experiment and after each event, a high resolution DTM of the parcel was automatically generated by means of a recently developed digital stereo-photogrammetric ground-based tech- nique. At the same time, sediment yield and runoff were measured. All the studied parcels were initially characterized by the absence of an internal channel system. Ini- tial topographies could basically be considered as random space functions with quasi- isotropic distribution of the elevations. Each DTM sequence can thus be regarded as an example of channel building process, from sheet flow erosion to the convergence and intersection of small flows to the full development of the surface, with a system of valleys and

  15. Spectral Unmixing Plate Reader: High-Throughput, High-Precision FRET Assays in Living Cells.

    PubMed

    Schaaf, Tory M; Peterson, Kurt C; Grant, Benjamin D; Thomas, David D; Gillispie, Gregory D

    2017-03-01

    We have developed a microplate reader that records a complete high-quality fluorescence emission spectrum on a well-by-well basis under true high-throughput screening (HTS) conditions. The read time for an entire 384-well plate is less than 3 min. This instrument is particularly well suited for assays based on fluorescence resonance energy transfer (FRET). Intramolecular protein biosensors with genetically encoded green fluorescent protein (GFP) donor and red fluorescent protein (RFP) acceptor tags at positions sensitive to structural changes were stably expressed and studied in living HEK cells. Accurate quantitation of FRET was achieved by decomposing each observed spectrum into a linear combination of four component (basis) spectra (GFP emission, RFP emission, water Raman, and cell autofluorescence). Excitation and detection are both conducted from the top, allowing for thermoelectric control of the sample temperature from below. This spectral unmixing plate reader (SUPR) delivers an unprecedented combination of speed, precision, and accuracy for studying ensemble-averaged FRET in living cells. It complements our previously reported fluorescence lifetime plate reader, which offers the feature of resolving multiple FRET populations within the ensemble. The combination of these two direct waveform-recording technologies greatly enhances the precision and information content for HTS in drug discovery.

  16. Development of compact high precision linear piezoelectric stepping positioner with nanometer accuracy and large travel range.

    PubMed

    Kang, Dongwoo; Lee, Moon G; Gweon, Daegab

    2007-07-01

    Many application areas such as semiconductor manufacture, precision optics alignment, and microbiological cell manipulation require ultraprecision positioning systems with a high positioning resolution and large motion range. This article describes the development of a compact high precision linear piezoelectric stepping positioner for precision alignment of optical elements. The positioner is designed to have a compact and symmetric structure, high positioning resolution, large motion range, high force density, adequate dynamic range, and power-off hold. The positioner is fabricated according to these specifications and performance evaluation tests are carried out. A resolution of 10 nm, speed of 1 mms, push force of 25 N, and stiffness of 10.4 N/microm are attained while maintaining a compact size of 32x42x60 mm(3). The required power consumption is 52.33 W. The test results confirm that the developed positioner could be successfully applied to the precision alignment of optical elements.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Research on high acceleration high precision air suspension control system performance evaluation algorithm

    NASA Astrophysics Data System (ADS)

    Ling, Xiang; Zhang, Yu

    2017-07-01

    The motion performance of the high acceleration high precision air suspension platform is affected by the electromechanical characteristics of the drive system, the fluid characteristics of the air suspension guide rail and the load disturbance. The mathematical model of the system is established, and the controller performance is designed based on the optimal objective function value. The ideal controller performance is proposed as the evaluation benchmark. The performance of the system is evaluated by the ratio of the optimal objective value and the evaluation benchmark. Based on the established evaluation index, the influence of noise disturbance and estimation vector on the stability and robustness of the system is evaluated, and the system performance is further optimized.

  19. SOLARIS 3-axis high load, low profile, high precision motorized positioner

    SciTech Connect

    Acome, Eric; Van Every, Eric; Deyhim, Alex; Zajac, Marcin

    2016-07-27

    A 3-axis optical table, shown in Figure 1, was designed, fabricated, and assembled for the SOLARIS synchrotron facility at the Jagiellonian University in Krakow, Poland. To accommodate the facility, the table was designed to be very low profile, as seen in Figure 2, and bear a high load. The platform has degrees of freedom in the vertical (Z) direction as well as horizontal transversal (X and Y) directions. The table is intended to sustain loads as large as 1500 kg which will be sufficient to support a variety of equipment to measure and facilitate synchrotron radiation. After assembly, the table was tested and calibrated to find its position error in the vertical direction. ADC has extensive experience designing and building custom complex high precision motion systems [1,2].

  20. Charge Breeding Techniques in an Electron Beam Ion Trap for High Precision Mass Spectrometry at TITAN

    NASA Astrophysics Data System (ADS)

    MacDonald, T. D.; Simon, M. C.; Bale, J. C.; Chowdhury, U.; Eibach, M.; Gallant, A. T.; Lennarz, A.; Simon, V. V.; Chaudhuri, A.; Grossheim, A.; Kwiatkowski, A. A.; Schultz, B. E.; Dilling, J.

    2012-10-01

    Penning trap mass spectrometry is the most accurate and precise method available for performing atomic mass measurements. TRIUMF's Ion Trap for Atomic and Nuclear science is currently the only facility to couple its Penning trap to a rare isotope facility and an electron beam ion trap (EBIT). The EBIT is a valuable tool for beam preparation: since the precision scales linearly with the charge state, it takes advantage of the precision gained by using highly charged ions. However, this precision gain is contingent on fast and efficient charge breeding. An optimization algorithm has been developed to identify the optimal conditions for running the EBIT. Taking only the mass number and half-life of the isotope of interest as inputs, the electron beam current density, charge breeding time, charge state, and electron beam energy are all specified to maximize this precision. An overview of the TITAN charge breeding program, and the results of charge breeding simulations will be presented.

  1. Characterization of radiometric calibration of LANDSAT-4 TM reflective bands

    NASA Technical Reports Server (NTRS)

    Barker, J. L.; Abrams, R. B.; Ball, D. L.; Leung, K. C.

    1984-01-01

    Prelaunch and postlaunch internal calibrator, image, and background data is to characterize the radiometric performance of the LANDSAT-4 TM and to recommend improved procedures for radiometric calibration. All but two channels (band 2, channel 4; band 5, channel 3) behave normally. Gain changes relative to a postlaunch reference for channels within a band vary within 0.5 percent as a group. Instrument gain for channels in the cold focal plane oscillates. Noise in background and image data ranges from 0.5 to 1.7 counts. Average differences in forward and reverse image data indicate a need for separate calibration processing of forward and reverse scans. Precision is improved by increasing the pulse integration width from 31 to 41 minor frames, depending on the band.

  2. New tools for high-precision positioning of optical elements in high-NA microscope objectives

    NASA Astrophysics Data System (ADS)

    Heil, Joachim; Bauer, Tobias; Mueller, Willi; Sure, Thomas; Wesner, Joachim

    2004-02-01

    The precise positioning of the individual optical elements is essential for attaining diffraction limited performance in high-numerical-aperture (high-NA) microscope objectives. Tolerances are in the micron range or lower for high-end objectives, e.g. for broad-band scanning confocal applications, metrology objectives in general, and especially for deep ultraviolet (DUV) applications. The ever increasing demands on imaging performance ask for the continuous development and improvement of specialized measurement equipment for the production line. Our award-winning 150x/0.90-DUV-AT-infinity/0 objective for wafer inspection and metrology at 248nm employs air spacings in its doublets because of the instability of optical cements against DUV radiation. This comes however at the cost of a higher number of surfaces and even higher precision demands on their geometry, orientation and positioning. We present several tools enabling us to meet these requirements. A Fourier transform fringe analysis scheme is adapted to high-NA Fizeau interferometry for surface characterization. A white light Mirau interferometer for dimensional measurements on lens groups with sub-μm resolution enables us to keep surface distance errors lower than 2 μm. Residual aberrations of the objective are compensated for by translating special correction elements under observation of the wave-front using a DUV-Twyman-Green interferometer, which also incorporates a 903nm branch for the parfocal adjustment of the infrared (IR) autofocus feature of the objective. To adjust the shifting element for the elimination of on-axis coma, we compute an artificial (real-time) star test from the interferogram, allowing interactive manipulations of the element while monitoring their influence on the point spread function (PSF).

  3. The Radiometric Map of Australia

    NASA Astrophysics Data System (ADS)

    Minty, Brian; Franklin, Ross; Milligan, Peter; Richardson, Murray; Wilford, John

    2009-12-01

    Geoscience Australia and the Australian State and Territory Geological Surveys have systematically surveyed most of the Australian continent over the past 40 years using airborne gamma-ray spectrometry to map potassium, uranium and thorium elemental concentrations at the Earth's surface. However, the individual surveys that comprise the national gamma-ray spectrometric radioelement database are not all registered to the same datum. This limits the usefulness of the database as it is not possible to easily combine surveys into regional compilations or make accurate comparisons between radiometric signatures in different survey areas. To solve these problems, Geoscience Australia has undertaken an Australia-Wide Airborne Geophysical Survey (AWAGS), funded under the Australian Government's Onshore Energy Security Program, to serve as a radioelement baseline for all current and future airborne gamma-ray spectrometric surveys in Australia. The AWAGS survey has been back-calibrated to the International Atomic Energy Agency's (IAEA) radioelement datum. We have used the AWAGS data to level the national radioelement database by estimating survey correction factors that, once applied, minimise both the differences in radioelement estimates between surveys (where these surveys overlap) and the differences between the surveys and the AWAGS traverses. The database is thus effectively levelled to the IAEA datum. The levelled database has been used to produce the first `Radiometric Map of Australia' - levelled and merged composite potassium (% K), uranium (ppm eU) and thorium (ppm eTh) grids over Australia at 100m resolution. Interpreters can use the map to reliably compare the radiometric signatures observed over different parts of Australia. This enables the assessment of key mineralogical and geochemical properties of bedrock and regolith materials from different geological provinces and regions with contrasting landscape histories.

  4. Research on high-precision hole measurement based on robot vision method

    NASA Astrophysics Data System (ADS)

    Song, Li-mei; Li, Da-peng; Qin, Ming-cui; Li, Zong-yan; Chang, Yu-lan; Xi, Jiang-tao

    2014-09-01

    A high-precision vision detection and measurement system using mobile robot is established for the industry field detection of motorcycle frame hole and its diameter measurement. The robot path planning method is researched, and the non-contact measurement method with high precision based on visual digital image edge extraction and hole spatial circle fitting is presented. The Canny operator is used to extract the edge of captured image, the Lagrange interpolation algorithm is utilized to determine the missing image edge points and calculate the centroid, and the least squares fitting method is adopted to fit the image edge points. Experimental results show that the system can be used for the high-precision real-time measurement of hole on motorcycle frame. The absolute standard deviation of the proposed method is 0.026 7 mm. The proposed method can not only improve the measurement speed and precision, but also reduce the measurement error.

  5. Classification of LIDAR Data for Generating a High-Precision Roadway Map

    NASA Astrophysics Data System (ADS)

    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.

  6. A rugged, high precision capacitance diaphragm low pressure gauge for cryogenic use

    NASA Astrophysics Data System (ADS)

    Lago, Leatitia; Herbeaux, Christian; Bol, Marc; Roy, Pascale; Manceron, Laurent

    2014-01-01

    In order to carry out precise laboratory measurements of infrared absorption intensities, line profiles of molecules and organic volatile compounds for atmospheric chemistry in planetary and upper earth atmospheric layers, precise gas pressure measurement between 10-3 and a few mbars in the 77-300 K temperature range is necessary. A prototype, rugged, precision capacitive pressure gauge for cryogenic use has been designed, built at SOLEIL and tested down to 77 K. The design includes corrosion-resistant materials and has been tailored to operate on a differential measurement scheme based on a simple, precision capacitance-to-digital converter chip, instead of high precision floating capacitive bridges, as are used in other designs. The designs conception and performance specifications are presented here, illustrated by a precision of better than 1% in the 0.2-40 mbar range, with a resolution of 2 × 10-3 mbar. The gauge is tunable and can be adjusted for higher precision and a better resolution, at the expense of the maximum high-pressure range.

  7. Proposed design for high precision refractive index sensor using integrated planar lightwave circuit

    NASA Astrophysics Data System (ADS)

    Maru, Koichi; Fujii, Yusaku; Zhang, Shulian; Hou, Wenmei

    2009-07-01

    A high precision and compact refractive index sensor is proposed. The combination of coarse measurement utilizing the change of the angle of refraction and fine measurement utilizing the phase change is newly proposed to measure absolute refractive index precisely. The proposed method does not need expensive optical measurement equipment such as an optical spectrum analyzer. The integrated planar lightwave circuit (PLC) technology enables us to obtain a compact sensor that is preferable for the practical use. The principle, design, and some configurations for precise refractive index measurement are described.

  8. Research on high precision equal-angle scanning method in rotary kiln temperature measurement system

    NASA Astrophysics Data System (ADS)

    Dai, Shaosheng; Guo, Zhongyuan; You, Changhui; Liu, Jinsong; Cheng, Yang; Tang, Huaming

    2016-05-01

    Aiming at traditional horizontal equal-angle scanning method's disadvantage of measurement error, a high precision equal-angle scanning method is proposed, the proposed method establishes a tilt scanning model by the following steps: introducing height variable, precisely calculating the viewing angle, building scanning model. The model is used to calculate scanning position on rotary kiln's surface, which helps to locate and track temperature variation. The experiment shows that the proposed method can effectively improve the precision of temperature spots' location on the rotary kiln surface.

  9. Development of a practical method of estimating electric power from various photovoltaic technologies with high precision

    NASA Astrophysics Data System (ADS)

    Ishii, Tetsuyuki; Sato, Ritsuko; Choi, Sungwoo; Chiba, Yasuo; Masuda, Atsushi

    2017-08-01

    The purpose of this study is to develop a method of estimating the electric power from various photovoltaic technologies with high precision. The actual outdoor performance of eight kinds (12 types) of photovoltaic (PV) modules has been measured since January 2012 in order to verify the precision of the method. Using ambient climatic datasets including solar irradiance, module temperature, and solar spectrum, the performance of these PV modules is corrected to the performance under standard test conditions (STC), which should be constant ideally. The results indicate that the performance of bulk crystalline silicon (c-Si) and copper indium gallium diselenide (CIGS) PV modules can be estimated with high precision (approximately less than ±2%). However, the estimation precision of thin-film Si and cadmium telluride (CdTe) PV modules is low because of the initial light-induced degradation and seasonal variation due to metastability.

  10. A High-Precision, Optical Polarimeter to Measure Inclinations of High Mass X-Ray Binaries

    NASA Astrophysics Data System (ADS)

    Wiktorowicz, Sloane; Matthews, K.; Kulkarni, S. R.

    2007-12-01

    While most astrophysical objects require many parameters in order to be fully described, black holes are unique in that only three parameters are required: mass, spin, and charge. Of these, mass and spin are enough to describe the black hole's gravitational field and event horizon location. Therefore, theory and observation may jointly pursue one or two quantities to uncover the progenitor star's history. Constraints on black hole mass exist for high mass X-ray binaries, such as Cygnus X-1, which is thought to consist of a 40 ± 10 solar mass O9.7Iab star and a 13.5-29 solar mass black hole (Ziolkowski 2005). While the constraints on the mass of the compact object are tight enough to declare that it is a black hole, they are sufficiently loose as to prohibit precise modeling of the progenitor star's mass. We have built an optical polarimeter for the Hale 5-m telescope at Mt. Palomar to provide an independent method for determining black hole mass. Degree of polarization will vary for an edge-on system, while position angle of net polarization will vary for a face-on system. Therefore, by monitoring the linear polarimetric variability of the binary, inclination can be estimated. Coupled with the known mass function of the binary from radial velocity work (Gies et al. 2003), inclination estimates constrain the mass of the black hole. Our polarimeter, POLISH (POLarimeter for Inclination Studies of High mass x-ray binaries), has achieved linear polarimetric precision of less than 10 parts per million on bright, unpolarized standard stars. We will also present results for polarized standard stars and Cygnus X-1 itself. This instrument has been funded by an endowment from the Moore Foundation.

  11. Radiometric studies of Mycobacterium lepraemurium.

    PubMed

    Camargo, E E; Larson, S M; Tepper, B S; Wagner, H N

    1976-01-01

    The radiometric method has been applied for studying the metabolism of M. lepraemurium and the conditions which might force or inhibit its metabolic activity in vitro. These organisms assimilate and oxidize (U-14C) glycerol, and (U-14C) acetate, but are unable to oxidize (U-14C) glucose, (U-14C) pyruvate, (U-14C) glycine and 14C-formate. When incubated at 30 degrees C M. lepraemurium oxidizes (U-14C) acetate to 14CO2 faster than 37 degrees C. The smae effect was observed with increasing concentrations of polysorbate 80 (Tween 80), or the 14C-substrate. No change in metabolic rate was observed when the organisms were kept at -20 degrees C for 12 days. Although tried several times, it was not possible to demonstrate any "inhibitors" of bacterial metabolism in the reaction system. The radiometric method seems to be an important tool for studying metabolic pathways and the influence of physical and biochemical factors on the metabolism of M. lepraemurium in vitro.

  12. FOTOMCAp: a new quasi-automatic code for high-precision photometry

    NASA Astrophysics Data System (ADS)

    Petrucci, R.; Jofré, J. E.

    2016-08-01

    The search for Earth-like planets using the transit technique has encouraged the development of strategies to obtain light curves with increasing precision. In this context we developed the fotomcap program. This is an iraf quasi-automatic code which employs the aperture correction method and allows to obtain high-precision light curves. In this contribution we describe how this code works and show the results obtained for planetary transits light curves.

  13. Construction of a versatile high precision ambient ionization source for direct analysis and imaging.

    PubMed

    Sampson, Jason S; Hawkridge, Adam M; Muddiman, David C

    2008-10-01

    The design and construction of a high precision ambient ionization source matrix-assisted laser desorption electrospray ionization (MALDESI) are described in full detail, including a complete parts list. The computer controlled high precision motion control system and high repetition rate Explorer laser are demonstrated during MALDESI-FT-ICR analysis of peptides and proteins ranging from 1 to 17 kDa. The high stability ionization source platform described herein demonstrates both the advantages of the new MALDESI source and versatility for application to numerous desorption and ionization techniques.

  14. Use of Terrestrial Laser Scanning Technology for Long Term High Precision Deformation Monitoring

    PubMed Central

    Vezočnik, Rok; Ambrožič, Tomaž; Sterle, Oskar; Bilban, Gregor; Pfeifer, Norbert; Stopar, Bojan

    2009-01-01

    The paper presents a new methodology for high precision monitoring of deformations with a long term perspective using terrestrial laser scanning technology. In order to solve the problem of a stable reference system and to assure the high quality of possible position changes of point clouds, scanning is integrated with two complementary surveying techniques, i.e., high quality static GNSS positioning and precise tacheometry. The case study object where the proposed methodology was tested is a high pressure underground pipeline situated in an area which is geologically unstable. PMID:22303152

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

    SciTech Connect

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

    2005-12-15

    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.

  16. The Next Step in Ice Flow Measurement from Optical Imagery: Comprehensive Mapping Of Ice Sheet Flow in Landsat 8 Imagery Using Spatial Frequency Filtering, Enabled by High Radiometric Sensitivity

    NASA Astrophysics Data System (ADS)

    Fahnestock, M. A.; Scambos, T. A.; Klinger, M. J.

    2014-12-01

    The advent of large area satellite coverage in the visible spectrum enabled satellite-based tracking of ice sheet flow just over twenty years ago. Following this, rapid development of techniques for imaging radar data enabled the wide-area mapping and time series coverage that SAR has brought to the documentation of changing ice discharge. We report on the maturation of feature tracking in visible-band satellite imagery of the ice sheets enabled by the high radiometric resolution and accurate geolocation delivered by Landsat 8, and apply this to mapping ice flow in the interiors of Antarctica and Greenland. The high radiometric resolution of Landsat 8 enables one to track subtle patterns on the surface of the ice sheet, unique at spatial scales of a few hundred meters, between images separated by multiple orbit cycles. In areas with significant dynamic topography generated by ice flow, this requires use of simple spatial filtering techniques first applied by Scambos et al. 1992. The result is densely sampled maps of surface motion that begin to rival the coverage available from SAR speckle tracking and interferometry. Displacement accuracy can approach one tenth of a pixel for reasonable chip sizes using conventional normalized cross-correlation; this can exceed the geolocation accuracy of the scenes involved, but coverage is sufficient to allow correction strategies based on very slow moving ice. The advance in radiometry, geo-location, and tracking tools is augmented by an increased rate of acquisition by Landsat 8. This helps mitigate the issue of cloud cover, as much of every 16-day orbit cycle over ice is acquired, maximizing the acquisition of clear-sky scenes. Using the correlation techniques common to IMCORR and later software, modern libraries, and single-cpu hardware, we are able to process full Landsat 8 scene pairs in a few minutes, allowing comprehensive analysis of ~1K available ice sheet image pairs in a few days.

  17. Design and algorithm research of high precision airborne infrared touch screen

    NASA Astrophysics Data System (ADS)

    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.

  18. A Non-Radiative Transfer Approach to Radiometric Vicarious Calibration

    NASA Technical Reports Server (NTRS)

    Ryan, Robert; Holekamp, Kara; Pagnutti, Mary; Stanley, Thomas

    2007-01-01

    TOA (top-of-atmosphere) radiance from high-spatial-resolution satellite imagery systems is important for a wide variety of research and applications. Many research initiatives require data with absolute radiometric accuracy better than a few percent. The conversion of satellite digital numbers to radiance depends on accurate radiometric calibration. A common method for determining and validating radiometric calibrations is to rely upon vicarious calibration approaches. Historically, vicarious calibration methods use radiative transfer codes with ground-based atmosphere and surface reflectance or radiance inputs for estimating TOA radiance values. These TOA radiance values are compared against the satellite digital numbers to determine the radiometric calibration. However, the radiative transfer codes used depend on many assumptions about the aerosol properties and the atmospheric point spread function. A measurement-based atmospheric radiance estimation approach for high-spatial-resolution, multispectral, visible/near-infrared sensors is presented that eliminates the use of radiative transfer codes and many of the underlying assumptions. A comparison between the radiative transfer and non-radiative transfer approaches is made.

  19. Radiometric sources for the Los Alamos National Laboratory calibration Laboratory

    SciTech Connect

    Maier, W.B. II; Holland, R.; Bender, S.; Byrd, D.; Michaud, F.D.; Moore, S.; O`Brian, T.R.

    1994-07-01

    Los Alamos is developing a laboratory that will support state of the art calibration of moderate-aperture instrumentation (< 40 cm diameter) having high spatial and thermal resolution. Highly accurate calibration in the reflected solar and thermal infrared spectral regions are required for newly developed instrumentation. Radiometric calibration of the instrumentation requires well-characterized, extensive sources of radiation from 0.45 to 12 {mu}m. For wavelengths above 2.5 {mu}m, blackbodies having temperature control and radiometric uniformity to within 100 mK are being designed and will be radiometrically characterized at the National Institute of Standards and Technology (NIST). For the spectral range 0.45--2.5 {mu}m, a ``whitebody`` integrating sphere equipped with tungsten-halogen lamps and enclosed inside a vacuum shroud will be used; this vacuum-compatible extensive standard diffuse source utilizes well-known technology and will be characterized at NIST`s existing facilities. Characterization of instrumental contrast performance for wavelengths, {lambda}, beyond 2.5 {mu}m will utilize a recently designed absolute variable-contrast IR radiometric calibrator, and preliminary data indicate that this calibrator will perform satisfactorily. Conceptual design and status of these extensive broad-band sources and of a monochromatic source to be used for spectral calibrations will be presented.

  20. Error analysis of high-rate GNSS precise point positioning for seismic wave measurement

    NASA Astrophysics Data System (ADS)

    Shu, Yuanming; Shi, Yun; Xu, Peiliang; Niu, Xiaoji; Liu, Jingnan

    2017-06-01

    High-rate GNSS precise point positioning (PPP) has been playing a more and more important role in providing precise positioning information in fast time-varying environments. Although kinematic PPP is commonly known to have a precision of a few centimeters, the precision of high-rate PPP within a short period of time has been reported recently with experiments to reach a few millimeters in the horizontal components and sub-centimeters in the vertical component to measure seismic motion, which is several times better than the conventional kinematic PPP practice. To fully understand the mechanism of mystified excellent performance of high-rate PPP within a short period of time, we have carried out a theoretical error analysis of PPP and conducted the corresponding simulations within a short period of time. The theoretical analysis has clearly indicated that the high-rate PPP errors consist of two types: the residual systematic errors at the starting epoch, which affect high-rate PPP through the change of satellite geometry, and the time-varying systematic errors between the starting epoch and the current epoch. Both the theoretical error analysis and simulated results are fully consistent with and thus have unambiguously confirmed the reported high precision of high-rate PPP, which has been further affirmed here by the real data experiments, indicating that high-rate PPP can indeed achieve the millimeter level of precision in the horizontal components and the sub-centimeter level of precision in the vertical component to measure motion within a short period of time. The simulation results have clearly shown that the random noise of carrier phases and higher order ionospheric errors are two major factors to affect the precision of high-rate PPP within a short period of time. The experiments with real data have also indicated that the precision of PPP solutions can degrade to the cm level in both the horizontal and vertical components, if the geometry of satellites is

  1. Molecular calipers for highly precise and accurate measurements of single-protein mechanics.

    PubMed

    Wang, Yanyan; Hu, Xiaodong; Bu, Tianjia; Hu, Chunguang; Hu, Xiaotang; Li, Hongbin

    2014-03-18

    Single-molecule atomic force spectroscopy (AFM) has evolved into a powerful technique toward elucidating conformational changes in proteins when exposed to applied force. AFM technologies that are currently available allow for precise measurements of proteins length changes during conformational transitions. However, because of systematic errors in piezo calibration as well as errors originating from fitting experimental data using a worm-like chain model of polymer elasticity, high-precision measurements of length changes do not necessarily translate into highly accurate measurements of length changes, resulting in uncertainty in obtaining structural information about protein conformational changes. Actually achieving highly precise and accurate force spectroscopy measurements remains a challenge. Here, we report a protein caliper method that eliminates systematic errors that occur during single-protein force spectroscopy measurements, and thus achieves highly precise and accurate length change measurements in protein mechanics studies. To do this, a series of loop elongation variants of the small protein GB1, which differ by 2, 5, 10, 15, and 24 amino acid residues, were engineered. Differential measurements of amino acid residue length obtained from different AFM setups result in a precise measure of the length of a single amino acid residue, which varies within different AFM setups because of systematic error between individual AFM piezoelectric calibrations. The measured length of a single amino acid residue from a given AFM setup is then used as a caliper for the given setup to eliminate systematic error, leading to highly accurate and precise measurements of the number of amino acid residues that are involved in a conformation change of a polypeptide chain. We further developed a more precise, robust, and model-free method to determine the apparent size of single amino acid residues and conformational changes of proteins. This method improves the accuracy of

  2. Research on high-precision laser displacement sensor-based error compensation model

    NASA Astrophysics Data System (ADS)

    Zhang, Zhifeng; Zhai, Yusheng; Su, Zhan; Qiao, Lin; Tang, Yiming; Wang, Xinjie; Su, Yuling; Song, Zhijun

    2015-08-01

    The triangulation measurement is a kind of active vision measurement. The laser triangulation displacement is widely used with advantages of non-contact, high precision, high sensitivity. The measuring error will increase with the nonlinear and noise disturbance when sensors work in large distance. The paper introduces the principle of laser triangulation measurement and analyzes the measuring error and establishes the compensation error. Spot centroid is extracted with digital image processing technology to increase noise-signal ratio. Results of simulation and experiment show the method can meet requirement of large distance and high precision.

  3. Methods for high precision 14C AMS measurement of atmospheric CO2 at LLNL

    SciTech Connect

    Graven, H D; Guilderson, T P; Keeling, R F

    2006-10-18

    Development of {sup 14}C analysis with precision better than 2{per_thousand} has the potential to expand the utility of {sup 14}CO{sub 2} measurements for carbon cycle investigations as atmospheric gradients currently approach traditional measurement precision of 2-5{per_thousand}. The AMS facility at the Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, produces high and stable beam currents that enable efficient acquisition times for large numbers of {sup 14}C counts. One million {sup 14}C atoms can be detected in approximately 25 minutes, suggesting that near 1{per_thousand} counting precision is economically feasible at LLNL. The overall uncertainty in measured values is ultimately determined by the variation between measured ratios in several sputtering periods of the same sample and by the reproducibility of replicate samples. Experiments on the collection of one million counts on replicate samples of CO{sub 2} extracted from a whole air cylinder show a standard deviation of 1.7{per_thousand} in 36 samples measured over several wheels. This precision may be limited by the reproducibility of Oxalic Acid I standard samples, which is considerably poorer. We outline the procedures for high-precision sample handling and analysis that have enabled reproducibility in the cylinder extraction samples at the <2{per_thousand} level and describe future directions to continue increasing measurement precision at LLNL.

  4. Flexible, non-contact and high-precision measurements of optical components

    NASA Astrophysics Data System (ADS)

    Beutler, A.

    2016-06-01

    A high-accuracy cylindrical coordinate measuring instrument developed for the measurement of optical components is presented. It is equipped with an optical point sensor system including a high aperture probe. This setup allows measurements to be performed with high accuracy in a flexible way. Applications include the measurement of the topography of high-precision aspheric and freeform lenses and diffractive structures. High measuring speeds guarantee the implementation in a closed-loop production process.

  5. Radiometrically accurate FTS for atmospheric emission observations

    NASA Technical Reports Server (NTRS)

    Revercomb, H. E.; Smith, W. L.; Stromovsky, L. A.; Knuteson, R. O.; Buijs, H.

    1989-01-01

    The calibration and operational performance of an FTIR-based airborne high-resolution interferometer sounder (HIS) for use in broadband measurements of atmospheric emission at 3.8-16.6 microns are described. The radiometric and wavelength calibration procedures in the laboratory involved the use of reference black bodies at 300 and 245 K and the known wavelength of the HIS HeNe laser (corrected for FOV effects), respectively. The atmospheric verification program included downlooking observations from the NASA U2/ER2 aircraft (where resolving power of 1800-3800 was demonstrated) and uplooking observations from the ground; good agreement with data from balloon-borne radiosondes is obtained, with absolute temperature uncertainties of less than 0.5 K and reproducibilities of 0.1-0.2 K over most of the measurement domain.

  6. GIFTS SM EDU Radiometric and Spectral Calibrations

    NASA Technical Reports Server (NTRS)

    Tian, J.; Reisse, R. a.; Johnson, D. G.; Gazarik, J. J.

    2007-01-01

    The Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) Sensor Module (SM) Engineering Demonstration Unit (EDU) is a high resolution spectral imager designed to measure infrared (IR) radiance using a Fourier transform spectrometer (FTS). The GIFTS instrument gathers measurements across the long-wave IR (LWIR), short/mid-wave IR (SMWIR), and visible spectral bands. The raw interferogram measurements are radiometrically and spectrally calibrated to produce radiance spectra, which are further processed to obtain atmospheric profiles via retrieval algorithms. This paper describes the processing algorithms involved in the calibration. The calibration procedures can be subdivided into three categories: the pre-calibration stage, the calibration stage, and finally, the post-calibration stage. Detailed derivations for each stage are presented in this paper.

  7. Thematic mapper: detailed radiometric and geometric characteristics

    USGS Publications Warehouse

    Kieffer, Hugh

    1983-01-01

    Those radiometric characteristics of the Landsat 4 Thematic Mapper (TM) that can be established without absolute calibration of spectral data have been examined. Subscenes of radiometric all raw data (B-data) were examined on an individual detector basis: areas of uniform radiance were used to characterize subtle radiometric differences and noise problems. A variety of anomalies have been discovered with magnitude of a few digital levels or less: the only problem not addressable by ground processing is irregular width of the digital levels. Essentially all of this non-ideal performance is incorporated in the fully processed (P-type) images, but disguised by the geometric resampling procedure. The overall performance of the Thematic Mapper is a great improvement over previous Landsat scanners. The effective resolution in radiance is degraded by about a factor of two by irregular width of the digital levels. Several detectors have a change of gain with a period of several scans, the largest effect is about 4%. These detectors appear to switch between two response levels during scan direction reversal; there is no apparent periodicity to these changes. This can cause small apparent difference between forward and reverse scans for portions of an image. The high-frequency noise level of each detector was characterized by the standard deviation of the first derivative in the sample direction across a flat field. Coherent sinusoidal noise patterns were determined using one-dimensional Fourier transforms. A "stitching" pattern in Band 1 has a period of 13.8 samples with a peak-to-peak amplitude ranging from 1 to 5 DN. Noise with a period of 3.24 samples is pronounced for most detectors in band 1, to a lesser extent in bands 2, 3, and 4, and below background noise levels in bands 5, 6, and 7. The geometric fidelity of the GSFC film writer used for Thematic Mapper (TM) images was assessed by measurement with accuracy bette than three micrometers of a test grid. A set of 55

  8. High Throughput, High Precision Hot Testing Tool for HBLED Wafer Level Testing

    SciTech Connect

    Solarz, Richard; McCord, Mark

    2015-12-31

    The Socrates research effort developed an in depth understanding and demonstrated in a prototype tool new precise methods for teh characterization of color characteristics and flux from individual LEDs for the production of uniform quality lighting. This effort was focused on improving the color quality and consistency of solid state lighting and potentially reducing characterization costs for all LED product types. The patented laser hot testing method was demonstrated to be far more accurate than all current state of the art color and flux characterization methods in use by the solid state lighting industry today. A seperately patented LED grouping method (statistical binning) was demonstrated to be a useful approach to improving utilization of entire lots of large color and flux distributions of manufactured LEDs for high quality color solid-state lighting. At the conclusion of the research in late 2015 the solid-state lighting industry was however generally satisfied with its existing production methods for high quality color products for the small segment of customers that demand it, albeit with added costs.

  9. Radiometric calibration of tempospatially modulated polarization interference imaging spectrometer.

    PubMed

    Gao, Peng; Ai, Jingjing; Zhang, Chunmin

    2016-12-10

    The tempospatially modulated polarization interference imaging spectrometer (TSMPIIS) nominated by the Ministry of Scence and Technology, takes part in the "Eleventh Five-Year National Science and Technology Exhibition." In order to improve the detecting precision of the TSMPIIS, its radiometric calibration scheme is proposed on the basis of the solar simulator, integrating sphere, monochromator, and spectroradiometer. Under the conditions of changing the exposure time and radiant brightness, the CCD linear responses for the TSMPIIS were first tested to validate the reliability of the radiometric calibration performed with a linear response model, and the linear errors were less than 0.15% and 1.15%, respectively. A novel method is put forward to calibrate the nonuniformity of CCD pixels, and the least squares method can commendably correct the uneven effect in the spatial direction. Besides, the absolute radiometric calibration establishes a corresponding relation between the dimensionless intensity output from the TSMPIIS and the target radiant brightness. The study lays the foundation for the engineering application of the TSMPIIS, such as remote sensing detection, and has an important significance for the development of our instrument and equipment technology with independent intellectual property rights.

  10. High precision locating control system based on VCM for Talbot lithography

    NASA Astrophysics Data System (ADS)

    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.

  11. Landsat-7 Enhanced Thematic Mapper plus radiometric calibration

    USGS Publications Warehouse

    Markham, B.L.; Boncyk, Wayne C.; Helder, D.L.; Barker, J.L.

    1997-01-01

    Landsat-7 is currently being built and tested for launch in 1998. The Enhanced Thematic Mapper Plus (ETM+) sensor for Landsat-7, a derivative of the highly successful Thematic Mapper (TM) sensors on Landsats 4 and 5, and the Landsat-7 ground system are being built to provide enhanced radiometric calibration performance. In addition, regular vicarious calibration campaigns are being planned to provide additional information for calibration of the ETM+ instrument. The primary upgrades to the instrument include the addition of two solar calibrators: the full aperture solar calibrator, a deployable diffuser, and the partial aperture solar calibrator, a passive device that allows the ETM+ to image the sun. The ground processing incorporates for the first time an off-line facility, the Image Assessment System (IAS), to perform calibration, evaluation and analysis. Within the IAS, processing capabilities include radiometric artifact characterization and correction, radiometric calibration from the multiple calibrator sources, inclusion of results from vicarious calibration and statistical trending of calibration data to improve calibration estimation. The Landsat Product Generation System, the portion of the ground system responsible for producing calibrated products, will incorporate the radiometric artifact correction algorithms and will use the calibration information generated by the IAS. This calibration information will also be supplied to ground processing systems throughout the world.

  12. Laboratory-based bidirectional reflectance distribution functions of radiometric tarps

    SciTech Connect

    Georgiev, Georgi T.; Butler, James J

    2008-06-20

    Laboratory-based bidirectional reflectance distribution functions (BRDFs) of radiometric tarp samples used in the vicarious calibration of Earth remote sensing satellite instruments are presented in this paper. The results illustrate the BRDF dependence on the orientation of the tarps' weft and warp threads. The study was performed using the GSFC scatterometer at incident zenith angles of 0 deg., 10 deg., and 30 deg.; scatter zenith angles from 0 deg. to 60 deg.; and scatter azimuth angles of 0 deg., 45 deg., 90 deg., 135 deg., and 180 deg.. The wavelengths were 485 nm, 550 nm, 633 nm, and 800 nm. The tarp's weft and warp dependence on BRDF is well defined at all measurement geometries and wavelengths. The BRDF difference can be as high as 8% at 0 deg. incident angle and 12% at 30 deg. incident angle. The fitted BRDF data show a very small discrepancy from the measured ones. New data on the forward and backscatter properties of radiometric tarps are reported. The backward scatter is well pronounced for the white samples. The black sample has well-pronounced forward scatter. The provided BRDF characterization of radiometric tarps is an excellent reference for anyone interested in using tarps for radiometric calibrations. The results are NIST traceable.

  13. Dynamic evaluation system for interpolation errors in the encoder of high precision

    NASA Astrophysics Data System (ADS)

    Wan, Qiu-hua; Wu, Yong-zhi; Zhao, Chang-hai; Liang, Li-hui; Sun, Ying; Jiang, Yong

    2009-05-01

    In order to measure dynamic interpolation errors of photoelectric encoder of high precision, the dynamic evaluation system of interpolation errors is introduced. Firstly, the fine Moiré signal of encoder which is collected with the high-speed data gathering card into the computer is treated to equiangular data with the method of linear interpolation. Then, the analysis of harmonic wave with the FFT is processed. Compared with the standard signal, the dynamic interpolation errors of the encoder are calculated. Experimental results show that the precision of the dynamic evaluation system of interpolation errors is +/-0.1 %( pitch). The evaluation system is simple, fast, high precision, and can be used in the working field of the encoder.

  14. Radiometric correction of LANDSAT data

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N.; Kumar, R. (Principal Investigator); Cavalcanti, L. A.

    1977-01-01

    The author has identified the following significant results. The six independent sensors of the multispectral band scanner are supposed to be identical; however, in actual practice, they may have different gain settings and offset factors, which result in the effect known as stripping (black lines at regular intervals) of the imagery. A simple two parameter method to correct the gain settings and offset factors of each of the sensors with respect to one sensor, taken as reference, was developed. This method assumes: (1) the response of a detector varies linearly with the radiance of radiation received, and (2) the means, as well as the standard deviations, of a reasonably large number of pixels, in a given wavelength band, are equal for each of the detectors for the radiometrically corrected data.

  15. Small satellite radiometric measurement system

    SciTech Connect

    Weber, P.G.

    1992-01-01

    A critical need for the US Global Change Research Program is to provide continuous, well-calibrated radiometric data for the earth's radiation budget. This paper describes a new, compact, relatively light-weight, adaptable radiometer which will provide both spectrally integrated measurements and data in selected spectral bands. The radiometer design is suitable for use on small satellites, aircraft, or remotely piloted aircraft (RPAs). An example of the implementation of this radiometer on a small satellite is given. Significant benefits derive from simultaneous measurements of specific narrow (in wavelength) spectral features; such data may be obtained by combining LARI with a compact spectrometer on the same platform. Well-chosen satellite orbits allow one to use data from other satellites (e.g. DMSP) to enhance the data product, or to provide superior coverage of specific locations. 23 refs.

  16. Small satellite radiometric measurement system

    SciTech Connect

    Weber, P.G.

    1992-01-01

    A critical need for the US Global Change Research Program is to provide continuous, well-calibrated radiometric data for the earth`s radiation budget. This paper describes a new, compact, relatively light-weight, adaptable radiometer which will provide both spectrally integrated measurements and data in selected spectral bands. The radiometer design is suitable for use on small satellites, aircraft, or remotely piloted aircraft (RPAs). An example of the implementation of this radiometer on a small satellite is given. Significant benefits derive from simultaneous measurements of specific narrow (in wavelength) spectral features; such data may be obtained by combining LARI with a compact spectrometer on the same platform. Well-chosen satellite orbits allow one to use data from other satellites (e.g. DMSP) to enhance the data product, or to provide superior coverage of specific locations. 23 refs.

  17. Precision of FLEET Velocimetry Using High-speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 micro sec, precisions of 0.5 m/s in air and 0.2 m/s in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision High Speed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  18. Precision of FLEET Velocimetry Using High-Speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 microseconds, precisions of 0.5 meters per second in air and 0.2 meters per second in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision HighSpeed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  19. Challenges in mold manufacturing for high precision molded diffractive optical elements

    NASA Astrophysics Data System (ADS)

    Pongs, Guido; Bresseler, Bernd; Schweizer, Klaus; Bergs, Thomas

    2016-09-01

    Isothermal precision glass molding of imaging optics is the key technology for mass production of precise optical elements. Especially for numerous consumer applications (e.g. digital cameras, smart phones, …), high precision glass molding is applied for the manufacturing of aspherical lenses. The usage of diffractive optical elements (DOEs) can help to further reduce the number of lenses in the optical systems which will lead to a reduced weight of hand-held optical devices. But today the application of molded glass DOEs is limited due to the technological challenges in structuring the mold surfaces. Depending on the application submicrometer structures are required on the mold surface. Furthermore these structures have to be replicated very precisely to the glass lens surface. Especially the micro structuring of hard and brittle mold materials such as Tungsten Carbide is very difficult and not established. Thus a multitude of innovative approaches using diffractive optical elements cannot be realized. Aixtooling has investigated in different mold materials and different suitable machining technologies for the micro- and sub-micrometer structuring of mold surfaces. The focus of the work lays on ultra-precision grinding to generate the diffractive pattern on the mold surfaces. This paper presents the latest achievements in diffractive structuring of Tungsten Carbide mold surfaces by ultra-precision grinding.

  20. High precision semi-automated vertebral height measurement using computed tomography: A phantom study.

    PubMed

    Tan, Sovira; Yao, Jianhua; Yao, Lawrence; Ward, Michael M

    2012-01-01

    The measurement of vertebral heights is necessary for the evaluation of many disorders affecting the spine. High precision is particularly important for longitudinal studies where subtle changes are to be detected. Computed tomography (CT) is the modality of choice for high precision studies. Radiography and dual emission X-ray absorptiometry (DXA) use 2D images to assess 3D structures, which can result in poor visualization due to the superimposition of extraneous anatomical objects on the same 2D space. We present a semi-automated computer algorithm to measure vertebral heights in the 3D space of a CT scan. The algorithm segments the vertebral bodies, extracts their end plates and computes vertebral heights as the mean distance between end plates. We evaluated the precision of our algorithm using repeat scans of an anthropomorphic vertebral phantom. Our method has high precision, with a coefficient of variation of only 0.197% and Bland-Altmann 95% limits of agreement of [-0.11, 0.13] mm. For local heights (anterior, middle, posterior) the algorithm was up to 4.2 times more precise than a manual mid-sagittal plane method.

  1. High precision measurement of the proton charge radius: The PRad experiment

    SciTech Connect

    Meziane, Mehdi

    2013-11-01

    The recent high precision measurements of the proton charge radius performed at PSI from muonic hydrogen Lamb shift puzzled the hadronic physics community. A value of 0.8418 {+-} 0.0007 fm was extracted which is 7{sigma} smaller than the previous determinations obtained from electron-proton scattering experiments and based on precision spectroscopy of electronic hydrogen. An additional extraction of the proton charge radius from electron scattering at Mainz is also in good agreement with these "electronic" determinations. An independent measurement of the proton charge radius from unpolarized elastic ep scattering using a magnetic spectrometer free method was proposed and fully approved at Jefferson Laboratory in June 2012. This novel technique uses the high precision calorimeter HyCal and a windowless hydrogen gas target which makes possible the extraction of the charge radius at very forward angles and thus very low momentum transfer Q{sup 2} up to 10{sup -4} (GeV/c){sup 2} with an unprecedented sub-percent precision for this type of experiment. In this paper, after a review of the recent progress on the proton charge radius extraction and the new high precision experiment PRad will be presented.

  2. High precision measurement of the proton charge radius: The PRad experiment

    SciTech Connect

    Meziane, Mehdi; Collaboration: PRad Collaboration

    2013-11-07

    The recent high precision measurements of the proton charge radius performed at PSI from muonic hydrogen Lamb shift puzzled the hadronic physics community. A value of 0.8418 ± 0.0007 fm was extracted which is 7σ smaller than the previous determinations obtained from electron-proton scattering experiments and based on precision spectroscopy of electronic hydrogen. An additional extraction of the proton charge radius from electron scattering at Mainz is also in good agreement with these 'electronic' determinations. An independent measurement of the proton charge radius from unpolarized elastic ep scattering using a magnetic spectrometer free method was proposed and fully approved at Jefferson Laboratory in June 2012. This novel technique uses the high precision calorimeter HyCal and a windowless hydrogen gas target which makes possible the extraction of the charge radius at very forward angles and thus very low momentum transfer Q{sup 2} up to 10{sup −4} (GeV/c){sup 2} with an unprecedented sub-percent precision for this type of experiment. In this paper, after a review of the recent progress on the proton charge radius extraction and the new high precision experiment PRad will be presented.

  3. CHEOPS: a space telescope for ultra-high precision photometry of exoplanet transits

    NASA Astrophysics Data System (ADS)

    Fortier, Andrea; Beck, Thomas; Benz, Willy; Broeg, Christopher; Cessa, Virginie; Ehrenreich, David; Thomas, Nicolas

    2014-08-01

    The CHaracterising ExOPlanet Satellite (CHEOPS) is a joint ESA-Switzerland space mission (expected to launch in 2017) dedicated to search for exoplanet transits by means of ultra-high precision photometry. CHEOPS will provide accurate radii for planets down to Earth size. Targets will mainly come from radial velocity surveys. The CHEOPS instrument is an optical space telescope of 30 cm clear aperture with a single focal plane CCD detector. The tube assembly is passively cooled and thermally controlled to support high precision, low noise photometry. The telescope feeds a re-imaging optic, which supports the straylight suppression concept to achieve the required Signal to Noise.

  4. Fabrication and Assembly of High-Precision Hinge and Latch Joints for Deployable Optical Instruments

    NASA Technical Reports Server (NTRS)

    Phelps, James E.

    1999-01-01

    Descriptions are presented of high-precision hinge and latch joints that have been co-developed, for application to deployable optical instruments, by NASA Langley Research Center and Nyma/ADF. Page-sized versions of engineering drawings are included in two appendices to describe all mechanical components of both joints. Procedures for assembling the mechanical components of both joints are also presented. The information herein is intended to facilitate the fabrication and assembly of the high-precision hinge and latch joints, and enable the incorporation of these joints into the design of deployable optical instrument systems.

  5. High precision NC lathe feeding system rigid-flexible coupling model reduction technology

    NASA Astrophysics Data System (ADS)

    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.

  6. A high precision attitude determination and control system for the UYS-1 nanosatellite

    NASA Astrophysics Data System (ADS)

    Chaurais, J. R.; Ferreira, H. C.; Ishihara, J. Y.; Borges, R. A.; Kulabukhov, A. M.; Larin, V. A.; Belikov, V. V.

    This paper presents the design of a high precision attitude determination and control system for the UYS-1 Ukrainian nanosatellite. Its main task is the 3-axis stabilization with less than 0.5° angle errors, so the satellite may take high precision photos of Earth's surface. To accomplish this task, this system comprises a star tracker and three reaction wheels. To avoid external disturbances and actuators faults, a PD-type and a PID-type robust controllers are simulated and the results are compared to an empirically adjusted PD controller.

  7. High-precision self-adaptive phase-calibration method for wavelength-tuning interferometry

    NASA Astrophysics Data System (ADS)

    Zhu, Xueliang; Zhao, Huiying; Dong, Longchao; Wang, Hongjun; Liu, Bingcai; Yuan, Daocheng; Tian, Ailing; Wang, Fangjie; Zhang, Chupeng; Ban, Xinxing

    2017-03-01

    We introduce a high-precision self-adaptive phase-calibration method for performing wavelength-tuning interferometry. Our method is insensitive to the nonlinearity of the phase shifter, even under random control. Intensity errors derived from laser voltage changes can be restrained by adopting this approach. Furthermore, this method can effectively overcome the influences from the background and modulation intensities in the interferogram, regardless of the phase structure. Numerical simulations and experiments are implemented to verify the validity of this high-precision calibration method.

  8. Towards high precision measurements of nuclear g-factors for the Be isotopes

    NASA Astrophysics Data System (ADS)

    Takamine, A.; Wada, M.; Okada, K.; Ito, Y.; Schury, P.; Arai, F.; Katayama, I.; Imamura, K.; Ichikawa, Y.; Ueno, H.; Wollnik, H.; Schuessler, H. A.

    2016-06-01

    We describe the present status of future high-precision measurements of nuclear g-factors utilizing laser-microwave double and laser-microwave-rf triple resonance methods for online-trapped, laser-cooled radioactive beryllium isotope ions. These methods have applicability to other suitably chosen isotopes and for beryllium show promise in deducing the hyperfine anomaly of 11Be with a sufficiently high precision to study the nuclear magnetization distribution of this one-neutron halo nucleus in a nuclear-model-independent manner.

  9. A radiometric kynurenine monooxygenase assay

    SciTech Connect

    Wiseman, J.S.; Nichols, J.S. )

    1990-01-01

    Kynurenine 3-monooxygenase is a flavin-dependent monooxygenase that catalyzes the oxidation of L-kynurenine to 3-hydroxy-L-kynurenine in the kynurenine pathway of tryptophan metabolism. The enzyme requires NADH or NADPH as a cofactor. A discontinuous assay that utilizes L-(3H)kynurenine as substrate is described. The assay offers high precision and a wide range of accessible substrate and cofactor concentrations. The assay was used to measure kinetic isotope effects and the stereospecificity of oxidation of the cofactor. Hydride is transferred from the A-side (pro-R) of NADH and NADPH since primary deuterium isotope effects were observed for both cofactors when they were deuterated on the A-side but not on the B-side. The large isotope effect on Vmax/Km for NADH is sensitive to the concentration of kynurenine, which indicates that NADH can bind before kynurenine.

  10. Spectrally and Radiometrically Stable, Wideband, Onboard Calibration Source

    NASA Technical Reports Server (NTRS)

    Coles, James B.; Richardson, Brandon S.; Eastwood, Michael L.; Sarture, Charles M.; Quetin, Gregory R.; Porter, Michael D.; Green, Robert O.; Nolte, Scott H.; Hernandez, Marco A.; Knoll, Linley A.

    2013-01-01

    The Onboard Calibration (OBC) source incorporates a medical/scientific-grade halogen source with a precisely designed fiber coupling system, and a fiber-based intensity-monitoring feedback loop that results in radiometric and spectral stabilities to within less than 0.3 percent over a 15-hour period. The airborne imaging spectrometer systems developed at the Jet Propulsion Laboratory incorporate OBC sources to provide auxiliary in-use system calibration data. The use of the OBC source will provide a significant increase in the quantitative accuracy, reliability, and resulting utility of the spectral data collected from current and future imaging spectrometer instruments.

  11. Absolute Radiometric Calibration of EUNIS-06

    NASA Technical Reports Server (NTRS)

    Thomas, R. J.; Rabin, D. M.; Kent, B. J.; Paustian, W.

    2007-01-01

    The Extreme-Ultraviolet Normal-Incidence Spectrometer (EUNIS) is a soundingrocket payload that obtains imaged high-resolution spectra of individual solar features, providing information about the Sun's corona and upper transition region. Shortly after its successful initial flight last year, a complete end-to-end calibration was carried out to determine the instrument's absolute radiometric response over its Longwave bandpass of 300 - 370A. The measurements were done at the Rutherford-Appleton Laboratory (RAL) in England, using the same vacuum facility and EUV radiation source used in the pre-flight calibrations of both SOHO/CDS and Hinode/EIS, as well as in three post-flight calibrations of our SERTS sounding rocket payload, the precursor to EUNIS. The unique radiation source provided by the Physikalisch-Technische Bundesanstalt (PTB) had been calibrated to an absolute accuracy of 7% (l-sigma) at 12 wavelengths covering our bandpass directly against the Berlin electron storage ring BESSY, which is itself a primary radiometric source standard. Scans of the EUNIS aperture were made to determine the instrument's absolute spectral sensitivity to +- 25%, considering all sources of error, and demonstrate that EUNIS-06 was the most sensitive solar E W spectrometer yet flown. The results will be matched against prior calibrations which relied on combining measurements of individual optical components, and on comparisons with theoretically predicted 'insensitive' line ratios. Coordinated observations were made during the EUNIS-06 flight by SOHO/CDS and EIT that will allow re-calibrations of those instruments as well. In addition, future EUNIS flights will provide similar calibration updates for TRACE, Hinode/EIS, and STEREO/SECCHI/EUVI.

  12. A high-precision calculation method for interface normal and curvature on an unstructured grid

    NASA Astrophysics Data System (ADS)

    Ito, Kei; Kunugi, Tomoaki; Ohno, Shuji; Kamide, Hideki; Ohshima, Hiroyuki

    2014-09-01

    In the volume-of-fluid algorithm, the calculations of the interface normal and curvature are crucially important for accurately simulating interfacial flows. However, few methods have been proposed for the high-precision interface calculation on an unstructured grid. In this paper, the authors develop a height function method that works appropriately on an unstructured grid. In the process, the definition of the height function is discussed, and the high-precision calculation method of the interface normal is developed to meet the necessary condition for a second-order method. This new method has highly reduced computational cost compared with a conventional high-precision method because the interface normal calculation is completed by solving relatively simple algebraic equations. The curvature calculation method is also discussed and the approximated quadric curve of an interface is employed to calculate the curvature. Following a basic verification, the developed height function method is shown to successfully provide superior calculation accuracy and highly reduced computational cost compared with conventional calculation methods in terms of the interface normal and curvature. In addition, the height function method succeeds in calculating accurately the slotted-disk revolution problem and the oscillating drop on unstructured grids. Therefore, the developed height function method is confirmed to be an efficient technique for the high-precision numerical simulation of interfacial flows on an unstructured grid.

  13. High-precision absolute distance and vibration measurement with frequency scanned interferometry

    SciTech Connect

    Yang, H.-J.; Deibel, Jason; Nyberg, Sven; Riles, Keith

    2005-07-01

    We report high-precision absolute distance and vibration measurements performed with frequency scanned interferometry using a pair of single-mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse Fabry-Perot interferometer was used to determine frequency changes during scanning. Two multiple-distance-measurement analysis techniques were developed to improve distance precision and to extract the amplitude and frequency of vibrations. Under laboratory conditions, measurement precision of {approx}50 nm was achieved for absolute distances ranging from 0.1 to 0.7 m by use of the first multiple-distance-measurement technique. The second analysis technique has the capability to measure vibration frequencies ranging from 0.1 to 100 Hz with an amplitude as small as a few nanometers without a priori knowledge.

  14. High-precision absolute distance and vibration measurement with frequency scanned interferometry.

    PubMed

    Yang, Hai-Jun; Deibel, Jason; Nyberg, Sven; Riles, Keith

    2005-07-01

    We report high-precision absolute distance and vibration measurements performed with frequency scanned interferometry using a pair of single-mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse Fabry-Perot interferometer was used to determine frequency changes during scanning. Two multiple-distance-measurement analysis techniques were developed to improve distance precision and to extract the amplitude and frequency of vibrations. Under laboratory conditions, measurement precision of approximately 50 nm was achieved for absolute distances ranging from 0.1 to 0.7 m by use of the first multiple-distance-measurement technique. The second analysis technique has the capability to measure vibration frequencies ranging from 0.1 to 100 Hz with an amplitude as small as a few nanometers without a priori knowledge.

  15. A high-precision K-band LFMCW radar for range measurement

    NASA Astrophysics Data System (ADS)

    Jia, Yingzhuo; Chen, Xiuwei; Zou, Yongliao

    2016-11-01

    K-band LFMCW radar may be applied in high-precision range measurement, if its range resolution is made be close to mm magnitude, good performance is not only needed in hardware design, algorithm selection and optimization is but also needed. In K-band LFMCW radar system, CZT algorithm is modified according to practical radar echo signal, its simulation model is built in the System Generator tool software, the corresponding algorithm is implemented in FPGA. K-band LFMCW radar may be applied in range measurement of great volume storage tank, the outfield experiment was done according to application, experiment result shows that range measurement precision may reach mm magnitude, the system can meet the requirement of remote high-precision measurement.

  16. High precision metrology method for unobscured Three Mirror Anastigmatic (TMA) mapping camera boresight

    NASA Astrophysics Data System (ADS)

    Zhao, Xi-ting; Jiao, Wen-chun; Liao, Zhi-bo

    2012-10-01

    High precision of mapping camera boresight directly affects the positioning accuracy of geographical location and photogrammetry. Although it can fulfill the request of good performance for unobscured TMA optical system, which adopted computer aided alignment method, single lens was unobscured which unable ascertain boresight by using lens centering technology, and boresight is randomicity as a result of compensating relation of multivariables. A novel method using the measurement of theodolite space intersection was proposed to rapidly and high accurately complete establish the relation between boresight and a cube in precision alignment stage, simultaneously, the relation of component deflexion and boresight have been simulated by computer model reverse optimization. Thus, the image quality and precision of boresight was effective operated according to the request of satellite assembly.

  17. High-precision tracking with non-blinking quantum dots resolves nanoscale vertical displacement.

    PubMed

    Marchuk, Kyle; Guo, Yijun; Sun, Wei; Vela, Javier; Fang, Ning

    2012-04-11

    Novel non-blinking quantum dots (NBQDs) were utilized in three-dimensional super-localization, high-precision tracking applications under an automated scanning-angle total internal reflection fluorescence microscope (SA-TIRFM). NBQDs were randomly attached to stationary microtubules along the radial axis under gliding assay conditions. By automatically scanning through a wide range of incident angles with different evanescent-field layer thicknesses, the fluorescence intensity decay curves were obtained. Fit with theoretical decay functions, the absolute vertical positions were determined with sub-10-nm localization precision. The emission intensity profile of the NBQDs attached to kinesin-propelled microtubules was used to resolve the self-rotation of gliding microtubules within a small vertical distance of ~50 nm. We demonstrate the applicability of NBQDs in high-precision fluorescence imaging experiments. © 2012 American Chemical Society

  18. High-Precision Floating-Point Arithmetic in ScientificComputation

    SciTech Connect

    Bailey, David H.

    2004-12-31

    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: some of these applications require roughly twice this level; others require four times; while still others require hundreds or more digits to obtain numerically meaningful results. Such calculations have been facilitated by new high-precision software packages that include high-level language translation modules to minimize the conversion effort. These activities have yielded a number of interesting new scientific results in fields as diverse as quantum theory, climate modeling and experimental mathematics, a few of which are described in this article. Such developments suggest that in the future, the numeric precision used for a scientific computation may be as important to the program design as are the algorithms and data structures.

  19. High-precision rotation angle measurement method based on monocular vision.

    PubMed

    Jin, Jing; Zhao, Lingna; Xu, Shengli

    2014-07-01

    To accurately measure the attitude angles (pitch, roll, and yaw) of a rigid object that rotates in a space, we propose a high-precision rotation angle measurement method based on monocular vision. This method combines camera self-calibration, multiview geometry, and 3D measurement. This monocular vision measuring system consists of an area scan CCD, a prime lens, and a spots array target, which are fixed on the measured object. We can calculate the rotation angle according to the rebuilt rotating spots array target by using this monocular vision measuring system. The measurement precision of rotation angle can reach 1 arc sec in this paper's experiments. This method has high measurement precision and good stability. Therefore we can widely use this method in machinery manufacturing, engineering measurement, aerospace, and the military.

  20. Figures deduction method for mast valuating interpolation errors of encoder with high precision

    NASA Astrophysics Data System (ADS)

    Yi, Jie; An, Li-min; Liu, Chun-xia

    2011-08-01

    With the development of technology, especially the need of fast accurately running after and orientating the aim of horizon and air, the photoelectrical rotary encoder with high precision has become the research hotspot in the fields of international spaceflight and avigation, the errors evaluation of encoder with high precision is the one of the key technology that must to be resolved. For the encoder with high precision, the interpolation errors is the main factor which affects its precision. Existing interpolation errors detection adopts accurate apparatus such as little angle measurement apparatus and optics polyhedron, requesting under the strict laboratory condition to carry on. The detection method is also time-consuming, hard to tackle and easy to introduce detect errors. This paper mainly studies the fast evaluation method of interpolation errors of encoder with high precision which is applied to the working field. Taking the Lissajou's figure produced by moiré fringe as foundation, the paper sets up the radius vector's mathematical model to represent figure's form deviation, analyses the implied parameters information of moiré fringe, the relation of the radius vector deviation and interpolation errors in the figures and puts forward the method of interpolation errors figures evaluation. Adopting figure deduction method, and directly from harmonic component of radius vector deviation toward harmonic component of interpolation errors, the interpolation errors can be gotten in the paper. Through data collecting card, the Moiré fringe signal is transmitted into the computer, then, the computer storages the data, using figures evaluation method to analyses the data, drawing the curve of interpolation errors. Comparing with interpolation errors drawing from traditional detect method, the change trend of the interpolation errors curve is similar, peak-peak value is almost equality. The result of experiment indicates: the method of the paper can be applied to

  1. Peculiarities of high-overtone transition probabilities in carbon monoxide revealed by high-precision calculation

    SciTech Connect

    Medvedev, Emile S.; Meshkov, Vladimir V.; Stolyarov, Andrey V.

    2015-10-21

    In the recent work devoted to the calculation of the rovibrational line list of the CO molecule [G. Li et al., Astrophys. J., Suppl. Ser. 216, 15 (2015)], rigorous validation of the calculated parameters including intensities was carried out. In particular, the Normal Intensity Distribution Law (NIDL) [E. S. Medvedev, J. Chem. Phys. 137, 174307 (2012)] was employed for the validation purposes, and it was found that, in the original CO line list calculated for large changes of the vibrational quantum number up to Δn = 41, intensities with Δn > 11 were unphysical. Therefore, very high overtone transitions were removed from the published list in Li et al. Here, we show how this type of validation is carried out and prove that the quadruple precision is indispensably required to predict the reliable intensities using the conventional 32-bit computers. Based on these calculations, the NIDL is shown to hold up for the 0 → n transitions till the dissociation limit around n = 83, covering 45 orders of magnitude in the intensity. The low-intensity 0 → n transition predicted in the work of Medvedev [Determination of a new molecular constant for diatomic systems. Normal intensity distribution law for overtone spectra of diatomic and polyatomic molecules and anomalies in overtone absorption spectra of diatomic molecules, Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka, 1984] at n = 5 is confirmed, and two additional “abnormal” intensities are found at n = 14 and 23. Criteria for the appearance of such “anomalies” are formulated. The results could be useful to revise the high-overtone molecular transition probabilities provided in spectroscopic databases.

  2. High precision position control of voice coil motor based on single neuron PID

    NASA Astrophysics Data System (ADS)

    Li, Liyi; Chen, Qiming; Tan, Guangjun; Zhu, He

    2013-01-01

    Voice coil motor(VCM) is widely used in high-speed and high-precision positioning control system in recent years. However, there are system uncertainty, nonlinear, modeling error, and external disturbances in the high-precision positioning control system, traditional PID control method is difficult to achieve precise positioning control. In this paper, a new position control strategy with a single neuron controller which has the capability of self-studying and self-adapting composed with PID controller is put forward, and the feedforward compensator is added to improve the dynamic response of the system in the position loop. Moreover, the disturbance observer is designed to suppress model parameter uncertainty and external disturbance signal in the current loop. In addition, the problem of high precision position control of VCM under the influence of significant disturbances is addressed, which including the gas-lubricated damping, the spring, the back EMF and ripple forces, on the basis, the mathematical model of VCM is established accurately. The simulation results show that this kind of controller can improve the dynamic characteristic and strengthen the robustness of the system, and the current loop with disturbance observer can also restrain disturbance and high frequency.

  3. Remote and high precision step height measurement with an optical fiber multiplexing interferometric system

    NASA Astrophysics Data System (ADS)

    Wang, Yunzhi; Xie, Fang; Ma, Sen; Chen, Liang

    2015-03-01

    An optical fiber multiplexing low coherence and high coherence interferometric system, which includes a Fizeau interferometer as the sensing element and a Michelson interferometer as the demodulating element, is designed for remote and high precision step height measurement. The Fizeau interferometer is placed in the remote field for sensing the measurand, while the Michelson interferometer which works in both modes of low coherence interferometry and high coherence interferometry is employed for demodulating the measurand. The range of the step height is determined by the low coherence interferometry and the value of it is measured precisely by the high coherence interferometry. High precision has been obtained by searching precisely the peak of the low coherence interferogram symmetrically from two sides of the low coherence interferogram and stabilizing the Michelson interferometer with a feedback loop. The maximum step height that could be measured is 6 mm while the measurement resolution is less than 1 nm. The standard deviation of 10 times measurement results of a step height of 1 mm configurated with two gauge blocks is 0.5 nm.

  4. Radiometric Characterization of the IKONOS, QuickBird, and OrbView-3 Sensors

    NASA Technical Reports Server (NTRS)

    Holekamp, Kara

    2006-01-01

    Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities can better understand their properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, satellite at-sensor radiance values were compared to those estimated by each independent team member to determine the sensor's radiometric accuracy. The combined results of this evaluation provide the user community with an independent assessment of these commercially available high spatial resolution sensors' absolute calibration values.

  5. Centroiding Experiment for Determining the Positions of Stars with High Precision

    NASA Astrophysics Data System (ADS)

    Yano, T.; Araki, H.; Hanada, H.; Tazawa, S.; Gouda, N.; Kobayashi, Y.; Yamada, Y.; Niwa, Y.

    2010-12-01

    We have experimented with the determination of the positions of star images on a detector with high precision such as 10 microarcseconds, required by a space astrometry satellite, JASMINE. In order to accomplish such a precision, we take the following two procedures. (1) We determine the positions of star images on the detector with the precision of about 0.01 pixel for one measurement, using an algorithm for estimating them from photon weighted means of the star images. (2) We determine the positions of star images with the precision of about 0.0001-0.00001 pixel, which corresponds to that of 10 microarcseconds, using a large amount of data over 10000 measurements, that is, the error of the positions decreases according to the amount of data. Here, we note that the procedure 2 is not accomplished when the systematic error in our data is not excluded adequately even if we use a large amount of data. We first show the method to determine the positions of star images on the detector using photon weighted means of star images. This algorithm, used in this experiment, is very useful because it is easy to calculate the photon weighted mean from the data. This is very important in treating a large amount of data. Furthermore, we need not assume the shape of the point spread function in deriving the centroid of star images. Second, we show the results in the laboratory experiment for precision of determining the positions of star images. We obtain that the precision of estimation of positions of star images on the detector is under a variance of 0.01 pixel for one measurement (procedure 1). We also obtain that the precision of the positions of star images becomes a variance of about 0.0001 pixel using about 10000 measurements (procedure 2).

  6. Active-passive hybrid piezoelectric actuators for high-precision hard disk drive servo systems

    NASA Astrophysics Data System (ADS)

    Chan, Kwong Wah; Liao, Wei-Hsin

    2006-03-01

    Positioning precision is crucial to today's increasingly high-speed, high-capacity, high data density, and miniaturized hard disk drives (HDDs). The demand for higher bandwidth servo systems that can quickly and precisely position the read/write head on a high track density becomes more pressing. Recently, the idea of applying dual-stage actuators to track servo systems has been studied. The push-pull piezoelectric actuated devices have been developed as micro actuators for fine and fast positioning, while the voice coil motor functions as a large but coarse seeking. However, the current dual-stage actuator design uses piezoelectric patches only without passive damping. In this paper, we propose a dual-stage servo system using enhanced active-passive hybrid piezoelectric actuators. The proposed actuators will improve the existing dual-stage actuators for higher precision and shock resistance, due to the incorporation of passive damping in the design. We aim to develop this hybrid servo system not only to increase speed of track seeking but also to improve precision of track following servos in HDDs. New piezoelectrically actuated suspensions with passive damping have been designed and fabricated. In order to evaluate positioning and track following performances for the dual-stage track servo systems, experimental efforts are carried out to implement the synthesized active-passive suspension structure with enhanced piezoelectric actuators using a composite nonlinear feedback controller.

  7. An optical fiber multiplexing interferometric system for measuring remote and high precision step height

    NASA Astrophysics Data System (ADS)

    Wang, Yunzhi; Xie, Fang; Ma, Sen; Chen, Liang

    2015-02-01

    In this paper, an optical fiber multiplexing interferometric system including a Fizeau interferometer and a Michelson interferometer is designed for remote and high precision step height measurement. The Fizeau interferometer which is inserted in the remote sensing field is used for sensing the measurand, while the Michelson interferometer which is stabilized by a feedback loop works in both modes of low coherence interferometry and high coherence interferometry to demodulate the measurand. The range of the step height is determined by the low coherence interferometry and the value of it is measured precisely by the high coherence interferometry. High precision has been obtained by using the symmetrical peak-searching method to address the peak of the low coherence interferogram precisely and stabilizing the Michelson interferometer with a feedback loop. The maximum step height that could be measured is 6 mm while the measurement resolution is less than 1 nm. The standard deviation of 10 times measurement results of a step height of 1 mm configurated with two gauge blocks is 0.5 nm.

  8. High-Precision Calibration of a Weld-On-The-Fly-System

    NASA Astrophysics Data System (ADS)

    Emmelmann, Claus; Schenk, Kerstin; Wollnack, Jörg; Kirchhoff, Marc

    Since 20 years the importance of laser based material processing increases constantly due to its significant higher process speed in comparison to conventional processing technologies. A scanner system for laser-remote-welding mounted on a robot hand to achieve more freedom in positioning the laser spot has been investigated. Additionally the scanner head contains two fixed cameras for measurements and process monitoring. To perform required measurements with maximum accuracy the allover system has to be calibrated precise. Therefore a combination of video metric measurement system and a laser tracker has been used. This paper depict this high-precision calibration process and shows reachable accuracies.

  9. Development and Utilization of High Precision Digital Elevation Data taken by Airborne Laser Scanner

    NASA Astrophysics Data System (ADS)

    Akutsu, Osamu; Ohta, Masataka; Isobe, Tamio; Ando, Hisamitsu, Noguchi, Takahiro; Shimizu, Masayuki

    2005-03-01

    Disasters caused by heavy rain in urban areas bring a damage such as chaos in the road and railway transport systems, power failure, breakdown of the telephone system and submersion of built up areas, subways and underground shopping arcades, etc. It is important to obtain high precision elevation data which shows the detailed landform because a slight height difference affects damages by flood very considerably. Therefore, The Geographical Survey Institute (GSI) is preparing 5m grid digital terrain model (DTM) based on precise ground elevation data taken by using airborne laser scanner. This paper describes the process and an example of the use of a 5m grid digital data set.

  10. Microplasma patterning of bonded microchannels using high-precision "injected" electrodes.

    PubMed

    Priest, Craig; Gruner, Philipp J; Szili, Endre J; Al-Bataineh, Sameer A; Bradley, James W; Ralston, John; Steele, David A; Short, Robert D

    2011-02-07

    A rapid, high-precision method for localised plasma-treatment of bonded PDMS microchannels is demonstrated. Patterned electrodes were prepared by injection of molten gallium into preformed microchannel guides. The electrode guides were prepared without any additional fabrication steps compared to conventional microchannel fabrication. Alignment of the "injected" electrodes is precisely controlled by the photomask design, rather than positioning accuracy of alignment tools. Surface modification is detected using a fluorescent dye (Rhodamine B), revealing a well-defined micropattern with regions less than 100 µm along the length of the microchannel.

  11. High-dose, high-precision treatment options for boosting cancer of the nasopharynx.

    PubMed

    Levendag, Peter C; Lagerwaard, Frank J; de Pan, Connie; Noever, Inge; van Nimwegen, Arent; Wijers, Oda; Nowak, Peter J C M

    2002-04-01

    The aim of the study is to define the role and type of high-dose, high-precision radiation therapy for boosting early staged T1,2a, but in particular locally advanced, T2b-4, nasopharyngeal cancer (NPC). Ninety-one patients with primary stage I-IVB NPC, were treated between 1991 and 2000 with 60-70Gy external beam radiation therapy (ERT) followed by 11-18Gy endocavitary brachytherapy (ECBT) boost. In 1996, for stage III-IVB disease, cisplatinum (CDDP)-based neoadjuvant chemotherapy (CHT) was introduced per protocol. Patients were analyzed for local control and overall survival. For a subset of 18 patients, a magnetic resonance imaging (MRI) scan at 46Gy was obtained. After matching with pre-treatment computed tomogram, patients (response) were graded into four categories; i.e. LD (T1,2a, with limited disease, i.e. disease confined to nasopharynx), LRD (T2b, with limited residual disease), ERD (T2b, with extensive residual disease), or patients initially diagnosed with T3,4 tumors. Dose distributions for ECBT (Plato-BPS v. 13.3, Nucletron) were compared to parallel-opposed three-dimensional conformal radiation therapy (Cadplan, Varian Dosetek v. 3.1), intensity modulated radiation therapy (IMRT) (Helios, Varian) and stereotactic radiotherapy (SRT) (X-plan, Radionics v. 2.02). For stage T1,2N0,1 tumors, at 2 years local control of 96% and overall survival of 80% were observed. For the poorest subset of patients, well/moderate/poorly differentiated T3,4 tumors, local control and overall survival at 2 years with CHT were 67 and 67%, respectively, vs. local control of 20% and overall survival of 12% without CHT. For LD and LRD, conformal target coverage and optimal sparing can be obtained with brachytherapy. For T2b-ERD and T3,4 tumors, these planning goals are better achieved with SRT and/or IMRT. The dosimetric findings, ease of application of the brachytherapy procedure, and the clinical results in early staged NPC, necessitates ERT combined with brachytherapy boost

  12. High precision measurements of the diamond Hugoniot in and above the melt region

    SciTech Connect

    Hicks, D; Boehly, T; Celliers, P; Bradley, D; Eggert, J; McWilliams, R S; Collins, G

    2008-08-05

    High precision laser-driven shock wave measurements of the diamond principal Hugoniot have been made at pressures between 6 and 19 Mbar. Shock velocities were determined with 0.3-1.1% precision using a velocity interferometer. Impedance matching analysis, incorporating systematic errors in the equation-of-state of the quartz standard, was used to determine the Hugoniot with 1.2-2.7% precision in density. The results are in good agreement with published ab initio calculations which predict a small negative melt slope along the Hugoniot, but disagree with previous laser-driven shock wave experiments which had observed a large density increase in the melt region. In the extensive solid-liquid coexistence regime between 6 and 10 Mbar these measurements indicate that the mixed phase may be slightly more dense than would be expected from a simple interpolation between liquid and solid Hugoniots.

  13. High precision tuning of state for memristive devices by adaptable variation-tolerant algorithm

    NASA Astrophysics Data System (ADS)

    Alibart, Fabien; Gao, Ligang; Hoskins, Brian D.; Strukov, Dmitri B.

    2012-02-01

    Using memristive properties common for titanium dioxide thin film devices, we designed a simple write algorithm to tune device conductance at a specific bias point to 1% relative accuracy (which is roughly equivalent to seven-bit precision) within its dynamic range even in the presence of large variations in switching behavior. The high precision state is nonvolatile and the results are likely to be sustained for nanoscale memristive devices because of the inherent filamentary nature of the resistive switching. The proposed functionality of memristive devices is especially attractive for analog computing with low precision data. As one representative example we demonstrate hybrid circuitry consisting of an integrated circuit summing amplifier and two memristive devices to perform the analog multiply-and-add (dot-product) computation, which is a typical bottleneck operation in information processing.

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

    PubMed

    Yin, Xuebing; Zhao, Huijie; Zeng, Junyu; Qu, Yufu

    2007-05-20

    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.

  15. High-precision branching ratio measurement for the superallowed {beta}{sup +} emitter {sup 62}Ga

    SciTech Connect

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

    2008-08-15

    A high-precision branching ratio measurement for the superallowed {beta}{sup +} decay of {sup 62}Ga was performed at the Isotope Separator and Accelerator (ISAC) radioactive ion beam facility. The 8{pi} spectrometer, an array of 20 high-purity germanium detectors, was employed to detect the {gamma} rays emitted following Gamow-Teller and nonanalog Fermi {beta}{sup +} decays of {sup 62}Ga, and the SCEPTAR plastic scintillator array was used to detect the emitted {beta} particles. Thirty {gamma} rays were identified following {sup 62}Ga 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 {sup 62}Ga, this branching ratio yields an ft value of 3074.3{+-}1.1 s, making {sup 62}Ga among the most precisely determined superallowed ft values. Comparison between the superallowed ft value determined in this work and the world-average corrected Ft value allows the large nuclear-structure-dependent correction for {sup 62}Ga 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.

  16. Development of high precision laser measurement to Space Debris and Applications in SHAO

    NASA Astrophysics Data System (ADS)

    Zhang, Zhongping; Chen, Juping; Xiong, Yaoheng; Han, Xingwei

    2016-07-01

    Artificial space debris has become the focus during the space exploration because of producing the damage for the future active spacecrafts and high precision measurement for space debris are required for debris surveillance and collision avoidance. Laser ranging technology is inherently high accurate and will play an important role in precise orbit determination, accurate catalog of space debris. Shanghai Astronomical Observatory (SHAO) of CAS, has been developing the technology of laser measurement to space debris for several years. According to characteristics of laser echoes from space debris and the experiences of relevant activities, high repetition rate, high power laser system and low dark noise APD detector with high quantum efficiency and high transmissivity of narrow bandwidth spectral filter are applied to laser measurement to space debris in SHAO. With these configurations, great achievements of laser measurement to space debris are made with hundreds of passes of laser data from space debris in the distance between 500km and 2500km with Radar Cross Section (RCS) of more than 10 m^{2} to less than 0.5m^{2} at the measuring precision of less than 1m (RMS). For better application of laser ranging technology, Chinese Space Debris Observation network, consisting of Shanghai, Changchun and Kunming station, has been preliminary developed and the coordinated observation has been performed to increase the measuring efficiency for space debris. It is referred from data that laser ranging technology can be as the essential high accuracy measurement technology in the study of space debris.

  17. A high-precision method for measurement of paleoatmospheric CO2 in small polar ice samples

    NASA Astrophysics Data System (ADS)

    Ahn, Jinho; Brook, Edward J.; Howell, Kate

    We describe a high-precision method, now in use in our laboratory, for measuring the CO2 mixing ratio of ancient air trapped in polar ice cores. Occluded air in ice samples weighing ˜8-15 g is liberated by crushing with steel pins at -35°C and trapped at -263°C in a cryogenic cold trap. CO2 in the extracted air is analyzed using gas chromatography. Replicate measurements for several samples of high-quality ice from the Siple Dome and Taylor Dome Antarctic ice cores have pooled standard deviations of <0.9 ppm. This high-precision technique is directly applicable to high-temporal-resolution studies for detection of small CO2 variations, for example CO2 variations of a few parts per million on millennial to decadal scales.

  18. A Radiometer for Precision Coherent Radiation Measurements

    PubMed Central

    Thomas, Douglas B.; Zalewski, Edward F.

    1992-01-01

    A radiometer has been designed for precision colierent radiation measurements and tested for long-term repeatability at wavelengths of 488 and 633 nm. The radiometer consists of a pn silicon photodiode maintained in a nitrogen atmosphere with a quartz window designed to eliminate interference problems. Ratio measurements between the radiometer and an absolute type detector were made over a period of 215 d. At 0.5 mW, the standard deviations were 0.008% and 0.009% at 488 and 633 nm, respectively. The maximum deviations from the mean were 0.016% and 0.015% at the respective wavelengths. Measurements were also made on the radiometer with respect to angular and spatial uniformity and linearity. The high precision, simplicity, and portability of the radiometer suggest it for use as a transfer standard for radiometric measurements. PMID:28053435

  19. A high-precision tunable millimeter-wave photonic LO reference for the ALMA telescope

    NASA Astrophysics Data System (ADS)

    Shillue, W.; Grammer, W.; Jacques, C.; Meadows, H.; Castro, J.; Banda, J.; Treacy, R.; Masui, Y.; Brito, R.; Huggard, P.; Ellison, B.; Cliche, J.-F.; Ayotte, S.; Babin, A.; Costin, F.; Latrasse, C.; Pelletier, F.; Picard, M.-J.; Poulin, M.; Poulin, P.

    2013-06-01

    The Atacama Large Millimeter Array is a radio telescope array of 66 antennas designed for high performance scientific imaging, covering a frequency range of 27-950 GHz. Each antenna has a front end with ten receiving bands, and each band has a local oscillator which is synchronized between all antennas. We describe a high precision tunable millimeter-wave photonic local oscillator reference system, which is used as the synchronizing reference for all ten bands on each receiver.

  20. Development of the Portable Synchrotron MIRRORCLE-CV for High Precision Non-Destructive Testing

    SciTech Connect

    Hasegawa, Daisuke; Toyosugi, Norio; Noh, Young Deok; Yamada, Takanori; Morita, Masaki; Mantey, Edward; Masaoka, Sei; Yamada, Hironari

    2007-01-19

    We started the development of the portable synchrotron MIRRORCLE-CV series, which provides a high quality x-ray beam for high precision non-destructive testing (NDT). Computer simulations for the magnetic field design and electron dynamics reveal that the outer diameter of the synchrotron magnet can be as small as 30 cm. This synchrotron size approaches that of a conventional x-ray tube.

  1. Extended- and Point-Source Radiometric Program

    DTIC Science & Technology

    1962-08-08

    Radiometric Measurements of Cs1 37 Sources Made with NaI Detector. . 60 6.2 Aerial Radiometric Measurements of Co 60 Sources Made with Bioplastic ...Hanford aircraft consisted of an NaI scintillator, bioplastic scintillator, and a 40-liter ionization chamber. The aircraft employed was a twin-engine...supply, amplifier, and count rate, was transistorized portable equipment designed and fabricated at Hanford. The bioplastic instrument consisted of a 5

  2. Lansat MSS, Radiometric Processing Improvement

    NASA Astrophysics Data System (ADS)

    Saunier, Sebastien; Salgues, Germain; Gascon, Ferran; Biaasutti, Roberto

    2016-08-01

    The reprocessing campaigns of Landsat European Space Agency (ESA) data archive have been initiated since 3 years [1]. As part of this project, the processing algorithms have been upgraded. This article focuses on the radiometric processing of historical data observed with the Multi Spectral Scanner (MSS) instruments on board Landsat 1, 2, 3, 4 and 5.The Landsat MSS data have been recorded data from 1972 up to 1990. The MSS instruments have been designed with four visible bands covering the near / infrared regions of the electromagnetic spectrum, allowing the spatial sampling of our Earth surface at 60 meter.The current calibration method has shown some limitations in case of data observed out of mid latitude areas, where the Earth surface is bright because of desert or snow. The resulting image data suffers from saturations and is not fit for the potential application purposes.Although, when saturation exist, further investigations have shown that the radiometry of the raw data involved in the production of the Level 1 images is generally correct. As consequences, experiments have been undertaken to adapt the current processing in order to produce image data saturation free products.

  3. Radiometric calibration updates to the Landsat collection

    NASA Astrophysics Data System (ADS)

    Micijevic, Esad; Haque, Md. Obaidul; Mishra, Nischal

    2016-09-01

    The Landsat Project is planning to implement a new collection management strategy for Landsat products generated at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center. The goal of the initiative is to identify a collection of consistently geolocated and radiometrically calibrated images across the entire Landsat archive that is readily suitable for time-series analyses. In order to perform an accurate land change analysis, the data from all Landsat sensors must be on the same radiometric scale. Landsat 7 Enhanced Thematic Mapper Plus (ETM+) is calibrated to a radiance standard and all previous sensors are cross-calibrated to its radiometric scale. Landsat 8 Operational Land Imager (OLI) is calibrated to both radiance and reflectance standards independently. The Landsat 8 OLI reflectance calibration is considered to be most accurate. To improve radiometric calibration accuracy of historical data, Landsat 1-7 sensors also need to be cross-calibrated to the OLI reflectance scale. Results of that effort, as well as other calibration updates including the absolute and relative radiometric calibration and saturated pixel replacement for Landsat 8 OLI and absolute calibration for Landsat 4 and 5 Thematic Mappers (TM), will be implemented into Landsat products during the archive reprocessing campaign planned within the new collection management strategy. This paper reports on the planned radiometric calibration updates to the solar reflective bands of the new Landsat collection.

  4. High-Precision 40Ar/39Ar dating of the Deccan Traps

    NASA Astrophysics Data System (ADS)

    Sprain, C. J.; Renne, P. R.; Richards, M. A.; Self, S.; Vanderkluysen, L.; Pande, K.; Morgan, L. E.; Cosca, M. A.

    2015-12-01

    The Deccan Traps (DT) have been strongly implicated over the past thirty years as a potential cause of the mass extinctions at the Cretaceous-Paleogene boundary (KPB). While a broad coincidence between the DT eruptions and the KPB is increasingly clear, variables such as tempo, volume of eruptions, and amount of associated climate-modifying volatiles, are too poorly constrained to properly assess causality. In order to appropriately test whether the DT played a role in the mass extinctions a high-precision geochronologic framework defining the timing and tempo of volcanic eruptions is needed. Recent high-precision U/Pb dating of zircons from inferred paleosols (red boles) and melt segregation horizons is the only available geochronology of the DT that is sufficiently precise to resolve age differences of less than 100 ka (Schoene et al., 2015). While this technique can achieve high-precision dates for individual zircon crystals, protracted age distributions may not include the actual eruption age. Moreover, the applicability of U/Pb dating in the DT is limited as suitable material is only sporadically present and therefore the technique is unlikely to achieve the resolution necessary to assess the tempo of DT eruptions. To mediate these limitations, we present new high-precision 40Ar/39Ar ages for plagioclase separated from the lava flows sampled from each of ten chemostratigraphically-defined formations within the Western Ghats. Multiple (N = 1-4) plateau ages from each sample and detailed neutron fluence monitoring during irradiation yield ages with precision commonly better than 100 ka (1 sigma). Results provide the first precise location of the KPB within the DT eruption sequence, which approximately coincides with major changes in eruption frequency, flow-field volumes, extent of crustal contamination, and degree of fractionation. Collectively, these results suggest that a state shift occurred in the DT magma system within ~50 ka of the Chicxulub impact

  5. High-precision optical systems with inexpensive hardware: a unified alignment and structural design approach

    NASA Astrophysics Data System (ADS)

    Winrow, Edward G.; Chavez, Victor H.

    2011-09-01

    High-precision opto-mechanical structures have historically been plagued by high costs for both hardware and the associated alignment and assembly process. This problem is especially true for space applications where only a few production units are produced. A methodology for optical alignment and optical structure design is presented which shifts the mechanism of maintaining precision from tightly toleranced, machined flight hardware to reusable, modular tooling. Using the proposed methodology, optical alignment error sources are reduced by the direct alignment of optics through their surface retroreflections (pips) as seen through a theodolite. Optical alignment adjustments are actualized through motorized, sub-micron precision actuators in 5 degrees of freedom. Optical structure hardware costs are reduced through the use of simple shapes (tubes, plates) and repeated components. This approach produces significantly cheaper hardware and more efficient assembly without sacrificing alignment precision or optical structure stability. The design, alignment plan and assembly of a 4" aperture, carbon fiber composite, Schmidt-Cassegrain concept telescope is presented.

  6. High precision mobile location framework and its service based on virtual reference station of GPS

    NASA Astrophysics Data System (ADS)

    Liu, Chun; Sun, Liangyu; Yao, Lianbi

    2008-10-01

    The wireless communication technology and space technology are synchronously developed in recent years, which bring up the development of location based service (LBS). At present, many location technology methods were developed. However, all these methods can only provide a relative poor location precision and depend on high cost. The technology of Virtual Reference Station (VRS) of GPS is then involved in this paper. One of the objective in this paper is aim to give the LBS position structure to improve the mobile location position when a mobile position instrument is connected with VRS network. The cheaper GPS built-in Personal Designer Aid (PDA) is then used to achieve a higher precision by using RTCM data from existing VRS network. In order to obtain a high precision position when using the low-cost GPS receiver as a rover, the infrusture of the mobile differential correction system is then put forward. According to network transportation of RTCM via internet protocol (NTRIP), the message is communicated through wireless network, such as GPRS, CDMA and so on. The rough coordinate information is sent to VRS control center continuously, and then the VRS correction information is replied to rover in the data format of RTCM3.1. So the position will be updated based on mathematic solution after the decoding of RTCM3.1 data. The thought of LBS position can improve the precision, and can speed the LBS.

  7. Development and simulation of microfluidic Wheatstone bridge for high-precision sensor

    NASA Astrophysics Data System (ADS)

    Shipulya, N. D.; Konakov, S. A.; Krzhizhanovskaya, V. V.

    2016-08-01

    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.

  8. A study on using image serving technology for high precision mechanical positioning

    NASA Astrophysics Data System (ADS)

    Lin, Chuen-Horng; Hsiao, Muh-Don; Lai, Kuo-Jung

    2016-12-01

    This paper focused on using image server technology for high precision mechanical positioning. Rapid and precise positioning systems depend on the correct positions of CCD (Charge Coupled Device) video cameras, as well as on pattern matching modes. This study deals with four different positions captured by an automatic detection system employing a CCD video camera. According to a variety of hybrid image registration systems, this study proposes an entire set of methods for achieving optimal hybrid pattern matching. First, the four different position detections captured by the CCD video camera in low-resolution were examined. Next, the original position detection was carried out in high-resolution, in order to derive a precise set of CCD video camera positions. The fiducial mark (FM) was then divided into two types in the optimal option for pattern matching: the "fiducial mark" and "non-fiducial mark", which were then used for sampling. The automatic detection method is able to achieve the first pattern matching detection for recognized images. Unrecognized images or images that cannot have an FM were subjected to fine pattern matching detection. When it is not possible to find more than one FM after the proposed detection method, this suggests that the position of the CCD video camera should be reset. In this paper, the results of the experiment regarding the CCD camera precision location and the segmentation of fiducial patterns or insignificant fiducial patterns can detect and segment more unique areas and areas with unique features.

  9. Radiometric-microbiologic assay of niacin using Kloeckera brevis: analysis of human blood and food

    SciTech Connect

    Guilarte, T.R.; Pravlik, K.

    1983-12-01

    Kloeckera brevis, a yeast, was used as the test organism for the development of a radiometric-microbiologic (RMA) assay for niacin. The assay was determined to be sensitive to the 2 ng niacin per vial level and specific for the biologically active forms of this vitamin. The method was shown to be simple, accurate, and precise in the analysis of niacin in human blood and food. The application of the radiometric technique eliminates some of the problems encountered with conventional turbidimetric-microbiologic assay.

  10. Process influences and correction possibilities for high precision injection molded freeform optics

    NASA Astrophysics Data System (ADS)

    Dick, Lars; Risse, Stefan; Tünnermann, Andreas

    2016-08-01

    Modern injection molding processes offer a cost-efficient method for manufacturing high precision plastic optics for high volume applications. Besides form deviation of molded freeform optics, internal material stress is a relevant influencing factor for the functionality of a freeform optics in an optical system. This paper illustrates dominant influence parameters of an injection molding process relating to form deviation and internal material stress based on a freeform demonstrator geometry. Furthermore, a deterministic and efficient way for 3D mold correcting of systematic, asymmetrical shrinkage errors is shown to reach micrometer range shape accuracy at diameters up to 40 mm. In a second case, a stress-optimized parameter combination using unusual molding conditions was 3D corrected to reach high precision and low stress freeform polymer optics.

  11. High Precision Isotope Analyses Using Multi-Collector SIMS: Applications to Earth and Planetary Science.

    NASA Astrophysics Data System (ADS)

    Kita, N. T.; Ushikubo, T.; Valley, J. W.

    2008-05-01

    The CAMECA IMS-1280 large radius, multicollector ion microprobe at the Wisc-SIMS National Facility is capable of high accuracy and precision for in situ analysis of isotope ratios. With improved hardware stability and software capability, high precision isotope analyses are routinely performed, typically 5 min per spot. We have developed analytical protocols for stable isotope analyses of oxygen, carbon, Mg, Si and Sulfur using multi-collector Faraday Cups (MCFC) and achieved precision of 0.1-0.2 ‰ (1SD) from a typically 10μm spot analyses. A number of isotopically homogeneous mineral standards have been prepared and calibrated in order to certify the accuracy of analyses in the same level. When spatial resolution is critical, spot size is reduced down to sub- μm for δ 18O to obtain better than 0.5‰ (1SD) precision by using electron multiplier (EM) on multi-collection system. Multi-collection EM analysis is also applied at 10 ppm level to Li isotope ratios in zircon with precision better than 2‰ (1SD). A few applications will be presented. (1) Oxygen three isotope analyses of chondrules in ordinary chondrites revealed both mass dependent and mass independent oxygen isotope fractionations among chondrules as well as within individual chondrules. The results give constraints on the process of chondrule formation and origin of isotope reservoirs in the early solar system. (2) High precision 26Al-26Mg (half life of 0.73 Ma) chronology is applied to zoned melilite and anorthite from Ca, Al-rich inclusions (CAI) in Leoville meteorite, and a well-defined internal isochron is obtained. The results indicate the Al- Mg system was remained closed within 40ky of the crystallization of melilite and anorthite in this CAI. (3) Sub- μm spot analyses of δ18O in isotopically zoned zircon from high-grade metamorphism reveals a diffusion profile of ~6‰ over 2μm, indicating slow diffusion of oxygen in zircon. This result also implies that old Archean detrital zircons (> 4

  12. Precision of volumetric assessment of proximal femur microarchitecture from high-resolution 3T MRI.

    PubMed

    Hotca, Alexandra; Ravichandra, Shreyas; Mikheev, Artem; Rusinek, Henry; Chang, Gregory

    2015-01-01

    To evaluate the precision of measures of bone volume and bone volume fraction derived from high-resolution 3T MRI of proximal femur bone microarchitecture using non-uniformity correction. This HIPAA compliant, institutional review board approved study was conducted on six volunteers (mean age 56 ± 13 years), and written informed consent was obtained. All volunteers underwent a 3T FLASH MRI hip scan at three time points: baseline, second scan same day (intra-scans), and third scan one week later (inter-scans). Segmentation of femur images and values for total proximal femur volume (T), bone volume (B), and bone volume fraction (BVF) were calculated using in-house developed software, FireVoxel. Two types of non-uniformity corrections were applied to images (N3 and BiCal). Precision values were calculated using absolute percent error (APE). Statistical analysis was carried out using one-sample one-sided t test to observe the consistency of the precision and paired t test to compare between the various methods and scans. No significant differences in bone volume measurements were observed for intra- and inter-scans. When using non-uniformity correction and assessing all subjects uniformly at the level of the lesser trochanter, precision values overall improved, especially significantly (p < 0.05) when measuring bone volume, B . B values using the combination of N3 or BiCal with CLT had a significant consistent APE values of less than 2.5 %, while BVF values were all consistently and significantly lower than 2.5 % APE. Our results demonstrate the precision of high-resolution 3D MRI measures were comparable to that of dual-energy X-ray absorptiometry. Additional corrections to the analysis technique by cropping at the lesser trochanter or using non-uniformity corrections helped to improve precision. The high precision values from these MRI scans provide evidence for MRI of the proximal femur as a promising tool for osteoporosis diagnosis and treatment.

  13. High-precision reflectometry of multilayer coatings for extreme ultraviolet lithography

    SciTech Connect

    Wedowski, M; Underwood, J H; Gullikson, E M; Bajt, S; Folta, J A; Kearney, P A; Montcalm, C; Spiller, E

    1999-12-29

    Synchrotron-based reflectometry is an important technique for the precise determination of optical properties of reflective multilayer coatings for Extreme Ultraviolet Lithography (EUVL). Multilayer coatings enable normal incidence reflectances of more than 65% in the wavelength range between 11 and 15 nm. In order to achieve high resolution and throughput of EUVL systems, stringent requirements not only apply to their mechanical and optical layout, but also apply to the optical properties of the multilayer coatings. Therefore, multilayer deposition on near-normal incidence optical surfaces of projection optics, condenser optics and reflective masks requires suitable high-precision metrology. Most important, due to their small bandpass on the order of only 0.5 nm, all reflective multilayer coatings in EUVL systems must be wavelength-matched to within {+-}0.05 nm. In some cases, a gradient of the coating thickness is necessary for wavelength matching at variable average angle of incidence in different locations on the optical surfaces. Furthermore, in order to preserve the geometrical figure of the optical substrates, reflective multilayer coatings need to be uniform to within 0.01 nm in their center wavelength. This requirement can only be fulfilled with suitable metrology, which provides a precision of a fraction of this value. In addition, for the detailed understanding and the further development of reflective multilayer coatings a precision in the determination of peak reflectances is desirable on the order of 0.1%. Substrates up to 200 mm in diameter and 15 kg in mass need to be accommodated. Above requirements are fulfilled at beamline 6.3.2 of the Advanced Light Source (ALS) in Berkeley. This beamline proved to be precise within 0.2% (ms) for reflectance and 0.002 nm (rms) for wavelength.

  14. High-Precision Superallowed Fermi β Decay Measurements at TRIUMF-ISAC

    NASA Astrophysics Data System (ADS)

    Svensson, C. E.

    2016-09-01

    High-precision measurements of the ft -values for superallowed Fermi β decays between nuclear isobaric analogue states provide demanding tests of the electroweak Standard Model, including confirmation of the Conserved Vector Current hypothesis at the level of 1 . 2 ×10-4 , the most stringent limits on weak scalar currents, and the most precise determination of the Vud element of the CKM quark-mixing matrix. The Isotope Separator and Accelerator (ISAC) facility at TRIUMF produces high-quality beams of several of the superallowed emitters with world-record intensities and hosts a suite of state-of-the-art spectrometers for the measurement of superallowed half-lives, branching ratios, QEC values, and charge-radii. Recent highlights from the superallowed program at ISAC, including high-precision half-life measurements for the light superallowed emitters 10C, 14O, 18Ne, and 26mAl and branching-ratio measurements for the heavy superallowed emitters 62Ga and 74Rb will be presented. The impact of these measurements on tests of the Standard Model, and future developments in the superallowed program at ISAC with the new high-efficiency GRIFFIN γ - ray spectrometer, will be discussed. Research supported by the Natural Sciences and Engineering Research Council of Canada, the Canada Foundation for Innovation, and the Canada Research Chairs Program. TRIUMF receives federal funding via the National Research Council of Canada.

  15. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage.

    PubMed

    Yang, Z; Chen, H; Yu, T; Li, B

    2016-08-01

    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.

  16. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Chen, H.; Yu, T.; Li, B.

    2016-08-01

    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.

  17. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

    SciTech Connect

    Yang, Z. Yu, T.; Chen, H.; Li, B.

    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.

  18. Direct high-precision measurement of the magnetic moment of the proton.

    PubMed

    Mooser, A; Ulmer, S; Blaum, K; Franke, K; Kracke, H; Leiteritz, C; Quint, W; Rodegheri, C C; Smorra, C; Walz, J

    2014-05-29

    One of the fundamental properties of the proton is its magnetic moment, µp. So far µp has been measured only indirectly, by analysing the spectrum of an atomic hydrogen maser in a magnetic field. Here we report the direct high-precision measurement of the magnetic moment of a single proton using the double Penning-trap technique. We drive proton-spin quantum jumps by a magnetic radio-frequency field in a Penning trap with a homogeneous magnetic field. The induced spin transitions are detected in a second trap with a strong superimposed magnetic inhomogeneity. This enables the measurement of the spin-flip probability as a function of the drive frequency. In each measurement the proton's cyclotron frequency is used to determine the magnetic field of the trap. From the normalized resonance curve, we extract the particle's magnetic moment in terms of the nuclear magneton: μp = 2.792847350(9)μN. This measurement outperforms previous Penning-trap measurements in terms of precision by a factor of about 760. It improves the precision of the forty-year-old indirect measurement, in which significant theoretical bound state corrections were required to obtain µp, by a factor of 3. By application of this method to the antiproton magnetic moment, the fractional precision of the recently reported value can be improved by a factor of at least 1,000. Combined with the present result, this will provide a stringent test of matter/antimatter symmetry with baryons.

  19. High Precision Calculations of the Lennard-Jones Lattice Constants for Five Lattices

    NASA Astrophysics Data System (ADS)

    Stein, Matthew

    2017-01-01

    The total potential energy of a crystal as described by the Lennard-Jones (L-J) potential depends in part upon the calculation of lattice constants. Knowing these constants to high precision is useful for prediction of the lattice type and simulation of crystals such as rare-gas solids or germanium detectors, but reaching higher precision is computationally costly and challenging. Presented here is the extension of the precision of the lattice constants, Lp, up to 32 decimal digits, and in some cases corrections from previous publication. The Lp terms are given for 4 <= p <= 30 in the simple cubic, face-centered cubic, body-centered cubic, hexagonal-close-pack, and diamond lattices. This precision was obtained through the use of careful parallelization technique, exploitation of the symmetries of each lattice, and the ``onionization'' of the simulated crystal. The results of this computation, along with the tools and algorithm strategies to make this computation possible, are explained in detail graphically.

  20. Direct high-precision measurement of the magnetic moment of the proton

    NASA Astrophysics Data System (ADS)

    Mooser, A.; Ulmer, S.; Blaum, K.; Franke, K.; Kracke, H.; Leiteritz, C.; Quint, W.; Rodegheri, C. C.; Smorra, C.; Walz, J.

    2014-05-01

    One of the fundamental properties of the proton is its magnetic moment, µp. So far µp has been measured only indirectly, by analysing the spectrum of an atomic hydrogen maser in a magnetic field. Here we report the direct high-precision measurement of the magnetic moment of a single proton using the double Penning-trap technique. We drive proton-spin quantum jumps by a magnetic radio-frequency field in a Penning trap with a homogeneous magnetic field. The induced spin transitions are detected in a second trap with a strong superimposed magnetic inhomogeneity. This enables the measurement of the spin-flip probability as a function of the drive frequency. In each measurement the proton's cyclotron frequency is used to determine the magnetic field of the trap. From the normalized resonance curve, we extract the particle's magnetic moment in terms of the nuclear magneton: μp = 2.792847350(9)μN. This measurement outperforms previous Penning-trap measurements in terms of precision by a factor of about 760. It improves the precision of the forty-year-old indirect measurement, in which significant theoretical bound state corrections were required to obtain µp, by a factor of 3. By application of this method to the antiproton magnetic moment, the fractional precision of the recently reported value can be improved by a factor of at least 1,000. Combined with the present result, this will provide a stringent test of matter/antimatter symmetry with baryons.

  1. High-precision image aided inertial navigation with known features: observability analysis and performance evaluation.

    PubMed

    Jiang, Weiping; Wang, Li; Niu, Xiaoji; Zhang, Quan; Zhang, Hui; Tang, Min; Hu, Xiangyun

    2014-10-17

    A high-precision image-aided inertial navigation system (INS) is proposed as an alternative to the carrier-phase-based differential Global Navigation Satellite Systems (CDGNSSs) when satellite-based navigation systems are unavailable. In this paper, the image/INS integrated algorithm is modeled by a tightly-coupled iterative extended Kalman filter (IEKF). Tightly-coupled integration ensures that the integrated system is reliable, even if few known feature points (i.e., less than three) are observed in the images. A new global observability analysis of this tightly-coupled integration is presented to guarantee that the system is observable under the necessary conditions. The analysis conclusions were verified by simulations and field tests. The field tests also indicate that high-precision position (centimeter-level) and attitude (half-degree-level)-integrated solutions can be achieved in a global reference.

  2. High-Precision Image Aided Inertial Navigation with Known Features: Observability Analysis and Performance Evaluation

    PubMed Central

    Jiang, Weiping; Wang, Li; Niu, Xiaoji; Zhang, Quan; Zhang, Hui; Tang, Min; Hu, Xiangyun

    2014-01-01

    A high-precision image-aided inertial navigation system (INS) is proposed as an alternative to the carrier-phase-based differential Global Navigation Satellite Systems (CDGNSSs) when satellite-based navigation systems are unavailable. In this paper, the image/INS integrated algorithm is modeled by a tightly-coupled iterative extended Kalman filter (IEKF). Tightly-coupled integration ensures that the integrated system is reliable, even if few known feature points (i.e., less than three) are observed in the images. A new global observability analysis of this tightly-coupled integration is presented to guarantee that the system is observable under the necessary conditions. The analysis conclusions were verified by simulations and field tests. The field tests also indicate that high-precision position (centimeter-level) and attitude (half-degree-level)-integrated solutions can be achieved in a global reference. PMID:25330046

  3. Determination of the half-life of 213Fr with high precision

    NASA Astrophysics Data System (ADS)

    Fisichella, M.; Musumarra, A.; Farinon, F.; Nociforo, C.; Del Zoppo, A.; Figuera, P.; La Cognata, M.; Pellegriti, M. G.; Scuderi, V.; Torresi, D.; Strano, E.

    2013-07-01

    High-precision measurement of half-life and Qα value of neutral and highly charged α emitters is a major subject of investigation currently. In this framework, we recently pushed half-life measurements of neutral emitters to a precision of a few per mil. This result was achieved by using different techniques and apparatuses at Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud (INFN-LNS) and GSI Darmstadt. Here we report on 213Fr half-life determination [T1/2(213Fr) = 34.14±0.06 s] at INFN-LNS, detailing the measurement protocol used. Direct comparison with the accepted value in the literature shows a discrepancy of more than three sigma. We propose this new value as a reference, discussing previous experiments.

  4. Geometrical aspects of laser-drilled high precision holes for flow control applications

    NASA Astrophysics Data System (ADS)

    Giedl, Roswitha; Helml, H.-J.; Wagner, F. X.; Wild, Michael J.

    2003-11-01

    Laser drilling has become a valuable tool for the manufacture of high precision micro holes in a variety of materials. Laser drilled precision holes have applications in the automotive, aerospace, medical and sensor industry for flow control applications. The technology is competing with conventional machining micro electro-discharge machining in the field of fuel injection nozzle for combustion engines. Depending on the application, laser and optics have to be chosen which suits the requirements. In this paper, the results achieved with different lasers and drilling techniques will be compared to the hole specifications in flow control applications. The issue of geometry control of high aspect ratio laser drilled holes in metals will be investigated. The comparison of flow measurement results to microscopic hole dimension measurement show that flow characteristics strongly depend on cavitation number during flow.

  5. Optical timing receiver for the NASA laser ranging system. Part 2: High precision time interval digitizer

    NASA Technical Reports Server (NTRS)

    Leskovar, B.; Turko, B.

    1977-01-01

    The development of a high precision time interval digitizer is described. The time digitizer is a 10 psec resolution stop watch covering a range of up to 340 msec. The measured time interval is determined as a separation between leading edges of a pair of pulses applied externally to the start input and the stop input of the digitizer. Employing an interpolation techniques and a 50 MHz high precision master oscillator, the equivalent of a 100 GHz clock frequency standard is achieved. Absolute accuracy and stability of the digitizer are determined by the external 50 MHz master oscillator, which serves as a standard time marker. The start and stop pulses are fast 1 nsec rise time signals, according to the Nuclear Instrument means of tunnel diode discriminators. Firing level of the discriminator define start and stop points between which the time interval is digitized.

  6. Application of a scattered-light radiometric power meter.

    PubMed

    Caron, James N; DiComo, Gregory P; Ting, Antonio C; Fischer, Richard P

    2011-04-01

    The power measurement of high-power continuous-wave laser beams typically calls for the use of water-cooled thermopile power meters. Large thermopile meters have slow response times that can prove insufficient to conduct certain tests, such as determining the influence of atmospheric turbulence on transmitted beam power. To achieve faster response times, we calibrated a digital camera to measure the power level as the optical beam is projected onto a white surface. This scattered-light radiometric power meter saves the expense of purchasing a large area power meter and the required water cooling. In addition, the system can report the power distribution, changes in the position, and the spot size of the beam. This paper presents the theory of the scattered-light radiometric power meter and demonstrates its use during a field test at a 2.2 km optical range. © 2011 American Institute of Physics

  7. On the Mitigation of Solar Index Variability for High Precision Orbit Determination in Low Earth Orbit

    DTIC Science & Technology

    2016-09-16

    and ANal- ysis ( OCEAN ) tool to evaluate solution accuracy and predictive capabilities of each combination. In all test cases examined, using either the...Orbit Covariance Estimation and ANalysis ( OCEAN ) high precision orbit deter- mination tool in order to determine the suitability of each model for...the National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center (SWPC). There is an extensive body of work studying the

  8. Laser interferometric high-precision geometry (angle and length) monitor for JASMINE

    NASA Astrophysics Data System (ADS)

    Niwa, Y.; Arai, K.; Ueda, A.; Sakagami, M.; Gouda, N.; Kobayashi, Y.; Yamada, Y.; Yano, T.

    2008-07-01

    The telescope geometry of JASMINE should be stabilized and monitored with the accuracy of about 10 to 100 pm or 10 to 100 prad of rms over about 10 hours. For this purpose, a high-precision interferometric laser metrology system is employed. Useful techniques for measuring displacements on extremely small scales are the wave-front sensing method and the heterodyne interferometrical method. Experiments for verification of measurement principles are well advanced.

  9. Approach for designing and developing high-precision integrative systems for strip flatness detection.

    PubMed

    Ouyang, Qi; Wen, Cong; Song, Yongduan; Dong, Xingchen; Zhang, Xinglan

    2015-10-01

    In this paper, we propose an approach for designing and developing high-precision integrative systems for strip flatness detection. Algorithms are developed for camera calibration, which are more accurate than the general method calculating all the camera parameters. On the basis of this method, a detection system is developed including an integrative device for easy calculation and repeated usage. On-site experiment results confirm that the proposed method works well under hostile environmental conditions in mills.

  10. VizieR Online Data Catalog: High-precision abundances for stars with planets (Ramirez+, 2014)

    NASA Astrophysics Data System (ADS)

    Ramirez, I.; Melendez, J.; Asplund, M.

    2013-11-01

    High-precision stellar parameters and chemical abundances are presented for 111 stars; 52 of them are late-F type dwarfs and 59 are metal-rich solar analogs. The atomic linelist employed in the derivation of chemical abundances is also given. This linelist includes hyperfine structure parameters for some species. The stars' isochrone masses and ages are also reported, along with estimates of chromospheric activity. (5 data files).

  11. Usefulness of precise time stamping for exposing network characteristics on high-speed links

    NASA Astrophysics Data System (ADS)

    Kitatsuji, Yoshinori; Tsuru, Masato; Katsuno, Satoshi; Oie, Yuji

    2004-09-01

    To expose network characteristics by active/passive measurements, measuring some timing issues such as one-way delay, one-way queuing delay, and inter-packet time is essential, and is conducted by time-stamping for packets passing through an observation point. However, emerging high-speed networks require very high precision of time-stamping, far beyond the precision of conventional software-based time-stamping systems such as 'tcpdump'. For example, the inter-packet time of two consecutive 64-byte length packets on a giga-bit link can be less than 0.001 msec. In this paper, to demonstrate the usefulness and strong necessity of precise time-stamping on high-speed links, experiments of network measurements over a nation-wide IPv6 testbed in Japan have been performed, using a hardware-based time-stamping system that can synchronize to GPS with a high resolution of 0.0001 msec and within a small error of 0.0003 msec. In our experiments, several interesting results are seen, e.g., i) the distribution of one-way queuing delay exhibits a considerable difference depending on the size and the type (UDP/ICMP) of packets; ii) the minimal one-way delays for various sizes of UDP/ICMP packets give an accurate estimate of the transmission delay and the propagation delay; iii) the correlation between interpacket times at the sender and the receiver sides in a sequence of TCP ACK packets clearly shows the degree of ACK compression; iv) the inter-packet time in a UDP stream generated by a DV streaming application shows three dominant sending rates and a very rare peak rate, which might provide crucial information to bandwidth dimensioning; all of which would indicate the usefulness of precise time-stamping.

  12. A highly efficient, compact Yb:KYW laser for mobile precision systems

    SciTech Connect

    Kuznetsov, S A; Pivtsov, V S

    2014-05-30

    We have developed a promising scheme of a multimodediode-pumped ytterbium laser. The Yb:KYW laser in the cw regime demonstrates record-high differential (40%) and total optical (35%) efficiencies. Mode locking is realised, which allows the scheme to be used for the development of compact laser systems, such as mobile femtosecond precision synthesisers. The peculiarities of the laser operation and ways of further improving its efficiency are discussed. (lasers)

  13. A high precision gamma-ray spectrometer for the Mars-94 mission

    SciTech Connect

    Mitrofanov, I.G.; Anfimov, D.S.; Chernenko, A.M.

    1994-06-01

    The high precision gamma-ray spectrometer (PGS) is scheduled to be launched on the Mars-94 mission in October 1994, and to go into an elliptical polar orbit around Mars. The PGS consists of two high-purity germanium (Ge) detectors, associated electronics, and a passive cooler and will be mounted on one of the solar panels. The PGS will measure nuclear gamma-ray emissions from the martian surface, cosmic gamma-ray bursts, and the high-energy component of solar flares in the broad energy range from 50 KeV to 8 MeV using 4096 energy channels.

  14. A Novel Gravity Compensation Method for High Precision Free-INS Based on "Extreme Learning Machine".

    PubMed

    Zhou, Xiao; Yang, Gongliu; Cai, Qingzhong; Wang, Jing

    2016-11-29

    In recent years, with the emergency of high precision inertial sensors (accelerometers and gyros), gravity compensation has become a major source influencing the navigation accuracy in inertial navigation systems (INS), especially for high-precision INS. This paper presents preliminary results concerning the effect of gravity disturbance on INS. Meanwhile, this paper proposes a novel gravity compensation method for high-precision INS, which estimates the gravity disturbance on the track using the extreme learning machine (ELM) method based on measured gravity data on the geoid and processes the gravity disturbance to the height where INS has an upward continuation, then compensates the obtained gravity disturbance into the error equations of INS to restrain the INS error propagation. The estimation accuracy of the gravity disturbance data is verified by numerical tests. The root mean square error (RMSE) of the ELM estimation method can be improved by 23% and 44% compared with the bilinear interpolation method in plain and mountain areas, respectively. To further validate the proposed gravity compensation method, field experiments with an experimental vehicle were carried out in two regions. Test 1 was carried out in a plain area and Test 2 in a mountain area. The field experiment results also prove that the proposed gravity compensation method can significantly improve the positioning accuracy. During the 2-h field experiments, the positioning accuracy can be improved by 13% and 29% respectively, in Tests 1 and 2, when the navigation scheme is compensated by the proposed gravity compensation method.

  15. The interferometric method for measuring the generatrix straightness of high precision cone

    NASA Astrophysics Data System (ADS)

    Kang, Yanhui; Li, Huailu; Diao, Xiaofei; Zhang, Heng

    2015-10-01

    Cone parts are widely used in advanced manufacturing and precision mechanics, providing air proof, torque transmission and so on. The straightness of generatrix is one of the important parameters, and the required accuracy can be up to submicrometers. In order to realize the rapid and high precision generatrix measurement of smooth surface cone, a laser interferometric method is proposed based on the structure of typical Fizeau interferometer. The high precision optical flat is used for reference standard, and the surface of cone is the measured object. Two cylindrical lenses with different focal lengths realize unidirectional expansion of parallel beam, solving the problem of CCD camera fringe resolution. The interference fringes are curved because of the cone angle, and the peak is the basis for accurate determination of the generatrix. Two fringe processing techniques are described in detail, which are single-frame and phase-shifting methods. Single-frame method includes two steps, i.e. the calculation of integral part and decimal part. The advantage of this method is the simple measurement structure. Phase-shifting method needs piezoelectric transducer (PZT) to generate several steps for phase calculation, with the advantage of high accuracy. The experimental results show that the straightness measurement accuracy can be better than 0.2 μm.

  16. Next generation KATRIN high precision voltage divider for voltages up to 65kV

    NASA Astrophysics Data System (ADS)

    Bauer, S.; Berendes, R.; Hochschulz, F.; Ortjohann, H.-W.; Rosendahl, S.; Thümmler, T.; Schmidt, M.; Weinheimer, C.

    2013-10-01

    The KATRIN (KArlsruhe TRItium Neutrino) experiment aims to determine the mass of the electron antineutrino with a sensitivity of 200 meV by precisely measuring the electron spectrum of the tritium beta decay. This will be done by the use of a retarding spectrometer of the MAC-E-Filter type. To achieve the desired sensitivity the stability of the retarding potential of -18.6 kV has to be monitored with a precision of 3 ppm over at least two months. Since this is not feasible with commercial devices, two ppm-class high voltage dividers were developed, following the concept of the standard divider for DC voltages of up to 100 kV of the Physikalisch-Technische Bundesanstalt (PTB). In order to reach such high accuracies different effects have to be considered. The two most important ones are the temperature dependence of resistance and leakage currents, caused by insulators or corona discharges. For the second divider improvements were made concerning the high-precision resistors and the thermal design of the divider. The improved resistors are the result of a cooperation with the manufacturer. The design improvements, the investigation and the selection of the resistors, the built-in ripple probe and the calibrations at PTB will be reported here. The latter demonstrated a stability of about 0.1 ppm/month over a period of two years.

  17. High precision U-PB geochronology and implications for the tectonic evolution of the Superior Province

    NASA Technical Reports Server (NTRS)

    Davis, D. W.; Corfu, F.; Krogh, T. E.

    1986-01-01

    The underlying mechanisms of Archean tectonics and the degree to which modern plate tectonic models are applicable early in Earth's history continue to be a subject of considerable debate. A precise knowledge of the timing of geological events is of the utmost importance in studying this problem. The high precision U-Pb method has been applied in recent years to rock units in many areas of the Superior Province. Most of these data have precisions of about + or - 2-3 Ma. The resulting detailed chronologies of local igneous development and the regional age relationships furnish tight constraints on any Archean tectonic model. Superior province terrains can be classified into 3 types: (1) low grade areas dominated by meta-volcanic rocks (greenstone belts); (2) high grade, largely metaplutonic areas with abundant orthogneiss and foliated to massive I-type granitoid bodies; and (3) high grade areas with abundant metasediments, paragneiss and S-type plutons. Most of the U-Pb age determinations have been done on type 1 terrains with very few having been done in type 3 terrains. A compilation of over 120 ages indicates that the major part of igneous activity took place in the period 2760-2670 Ma, known as the Kenoran event. This event was ubiquitous throughout the Superior Province.

  18. Accurate time delay technology in simulated test for high precision laser range finder

    NASA Astrophysics Data System (ADS)

    Chen, Zhibin; Xiao, Wenjian; Wang, Weiming; Xue, Mingxi

    2015-10-01

    With the continuous development of technology, the ranging accuracy of pulsed laser range finder (LRF) is higher and higher, so the maintenance demand of LRF is also rising. According to the dominant ideology of "time analog spatial distance" in simulated test for pulsed range finder, the key of distance simulation precision lies in the adjustable time delay. By analyzing and comparing the advantages and disadvantages of fiber and circuit delay, a method was proposed to improve the accuracy of the circuit delay without increasing the count frequency of the circuit. A high precision controllable delay circuit was designed by combining the internal delay circuit and external delay circuit which could compensate the delay error in real time. And then the circuit delay accuracy could be increased. The accuracy of the novel circuit delay methods proposed in this paper was actually measured by a high sampling rate oscilloscope actual measurement. The measurement result shows that the accuracy of the distance simulated by the circuit delay is increased from +/- 0.75m up to +/- 0.15m. The accuracy of the simulated distance is greatly improved in simulated test for high precision pulsed range finder.

  19. Direct high-precision measurement of the magnetic moment of the proton

    NASA Astrophysics Data System (ADS)

    Quint, Wolfgang

    2015-05-01

    The challenge to measure the properties of the proton with great precision inspires very different branches of physics. The magnetic moment of the proton is a fundamental property of this particle. So far it has only been measured indirectly, by analyzing the spectrum of an atomic hydrogen maser in a magnetic field. Here we report the direct high-precision measurement of the magnetic moment of a single proton using the double Penning-trap technique. We drive proton-spin quantum jumps by a radio-frequency field in a Penning trap with a homogeneous magnetic field. The induced spin transitions are detected in a second trap with a strong superimposed magnetic inhomogeneity. This enables the measurement of the spin-flip probability as a function of the drive frequency. In each measurement the proton's cyclotron frequency is used to determine the magnetic field of the trap. From the normalized resonance curve, we extract the particle's magnetic moment in terms of the nuclear magneton: μp = 2.792 847 350 (9) μN. This measurement outperforms previous Penning-trap measurements in terms of precision by a factor of about 760. It improves the precision of the forty year-old indirect measurement by D. Kleppner et al., in which significant theoretical bound-state corrections were required to obtain μp, by a factor of 3. By application of this method to the antiproton magnetic moment, the fractional precision of the recently reported value can be improved by a factor of at least 1,000. Combined with the present result, this will provide a stringent test of matter/antimatter symmetry with baryons. Deutsche Forschungsgemeinschaft, grant QU122/3.

  20. Laboratory-Based BRDF Calibration of Radiometric Tarps

    NASA Technical Reports Server (NTRS)

    Georgiev, Georgi T.; Butler, James J.

    2007-01-01

    The current study provides the remote sensing community with important high accuracy laboratory-based BRDF calibration of radiometric tarps. The results illustrate the dependence of tarps' weft and warp threads orientation on BRDF. The study was done at incident angles of 0deg, 10deg, and 30deg; scatter zenith angles from 0deg to 60deg, and scatter azimuth angles of 0deg, 45deg, 90deg, 135deg, and 180deg. The wavelengths were 485nm, 550nm, 633nm and 800nm. The dependence is well defined at all measurement geometries and wavelengths. It can be as high as 8% at 0deg incident angle and 2% at 30deg incident angle. The fitted BRDF data show a very small discrepancy from the measured ones. New data on the forward and backscatter properties of radiometric tarps is reported. The backward scatter is well pronounced for the white samples. The black sample has well pronounced forward scatter. The BRDF characterization of radiometric tarps can be successfully extended to other structured surface fabric samples. The results are NIST traceable.

  1. All-digital precision processing of ERTS images

    NASA Technical Reports Server (NTRS)

    Bernstein, R. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Digital techniques have been developed and used to apply precision-grade radiometric and geometric corrections to ERTS MSS and RBV scenes. Geometric accuracies sufficient for mapping at 1:250,000 scale have been demonstrated. Radiometric quality has been superior to ERTS NDPF precision products. A configuration analysis has shown that feasible, cost-effective all-digital systems for correcting ERTS data are easily obtainable. This report contains a summary of all results obtained during this study and includes: (1) radiometric and geometric correction techniques, (2) reseau detection, (3) GCP location, (4) resampling, (5) alternative configuration evaluations, and (6) error analysis.

  2. Laser-generated ultrasound for high-precision cutting of tissue-mimicking gels (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    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 (<100 um). However, the previous demonstration used cells and tissues cultured on glass substrates. The glass substrates were found to be critical to cavitation, because ultrasound amplitude doubles due to the reflection from the substrate, thus allowing for reaching pressure amplitude to cavitation threshold. In other words, without the sound reflecting substrate, pressure amplitude may not be strong enough to create cavitation, thus limiting its application to only cultured biomaterials on the rigid substrates. By using laser-generated focused ultrasound without relying on sound-reflecting substrates, we demonstrate free-field cavitation in water and its application to high-precision cutting of tissue-mimicking gels. In the absence of a rigid boundary, strong pressure for cavitation was enabled by recently optimized photoacoustic lens with increased focal gain (>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).

  3. High-precision comparison of the antiproton-to-proton charge-to-mass ratio

    NASA Astrophysics Data System (ADS)

    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.

    2015-08-01

    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 to that for the proton and obtain . 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 <720 parts per trillion. By following the arguments of ref. 11, our result can be interpreted as a stringent test of the weak equivalence principle of general relativity using baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of < 8.7 × 10-7.

  4. High-precision comparison of the antiproton-to-proton charge-to-mass ratio.

    PubMed

    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 <720 parts per trillion. By following the arguments of ref. 11, our result can be interpreted as a stringent test of the weak equivalence principle of general relativity using baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of |α − 1| < 8.7 × 10(-7).

  5. Progress Towards a High-Precision Infrared Spectroscopic Survey of the H_3^+ Ion

    NASA Astrophysics Data System (ADS)

    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.

  6. A Review of LIDAR Radiometric Processing: From Ad Hoc Intensity Correction to Rigorous Radiometric Calibration

    PubMed Central

    Kashani, Alireza G.; Olsen, Michael J.; Parrish, Christopher E.; Wilson, Nicholas

    2015-01-01

    In addition to precise 3D coordinates, most light detection and ranging (LIDAR) systems also record “intensity”, loosely defined as the strength of the backscattered echo for each measured point. To date, LIDAR intensity data have proven beneficial in a wide range of applications because they are related to surface parameters, such as reflectance. While numerous procedures have been introduced in the scientific literature, and even commercial software, to enhance the utility of intensity data through a variety of “normalization”, “correction”, or “calibration” techniques, the current situation is complicated by a lack of standardization, as well as confusing, inconsistent use of terminology. In this paper, we first provide an overview of basic principles of LIDAR intensity measurements and applications utilizing intensity information from terrestrial, airborne topographic, and airborne bathymetric LIDAR. Next, we review effective parameters on intensity measurements, basic theory, and current intensity processing methods. We define terminology adopted from the most commonly-used conventions based on a review of current literature. Finally, we identify topics in need of further research. Ultimately, the presented information helps lay the foundation for future standards and specifications for LIDAR radiometric calibration. PMID:26561813

  7. A Review of LIDAR Radiometric Processing: From Ad Hoc Intensity Correction to Rigorous Radiometric Calibration.

    PubMed

    Kashani, Alireza G; Olsen, Michael J; Parrish, Christopher E; Wilson, Nicholas

    2015-11-06

    In addition to precise 3D coordinates, most light detection and ranging (LIDAR) systems also record "intensity", loosely defined as the strength of the backscattered echo for each measured point. To date, LIDAR intensity data have proven beneficial in a wide range of applications because they are related to surface parameters, such as reflectance. While numerous procedures have been introduced in the scientific literature, and even commercial software, to enhance the utility of intensity data through a variety of "normalization", "correction", or "calibration" techniques, the current situation is complicated by a lack of standardization, as well as confusing, inconsistent use of terminology. In this paper, we first provide an overview of basic principles of LIDAR intensity measurements and applications utilizing intensity information from terrestrial, airborne topographic, and airborne bathymetric LIDAR. Next, we review effective parameters on intensity measurements, basic theory, and current intensity processing methods. We define terminology adopted from the most commonly-used conventions based on a review of current literature. Finally, we identify topics in need of further research. Ultimately, the presented information helps lay the foundation for future standards and specifications for LIDAR radiometric calibration.

  8. Development and Validation of High Precision Thermal, Mechanical, and Optical Models for the Space Interferometry Mission

    NASA Technical Reports Server (NTRS)

    Lindensmith, Chris A.; Briggs, H. Clark; Beregovski, Yuri; Feria, V. Alfonso; Goullioud, Renaud; Gursel, Yekta; Hahn, Inseob; Kinsella, Gary; Orzewalla, Matthew; Phillips, Charles

    2006-01-01

    SIM Planetquest (SIM) is a large optical interferometer for making microarcsecond measurements of the positions of stars, and to detect Earth-sized planets around nearby stars. To achieve this precision, SIM requires stability of optical components to tens of picometers per hour. The combination of SIM s large size (9 meter baseline) and the high stability requirement makes it difficult and costly to measure all aspects of system performance on the ground. To reduce risks, costs and to allow for a design with fewer intermediate testing stages, the SIM project is developing an integrated thermal, mechanical and optical modeling process that will allow predictions of the system performance to be made at the required high precision. This modeling process uses commercial, off-the-shelf tools and has been validated against experimental results at the precision of the SIM performance requirements. This paper presents the description of the model development, some of the models, and their validation in the Thermo-Opto-Mechanical (TOM3) testbed which includes full scale brassboard optical components and the metrology to test them at the SIM performance requirement levels.

  9. Algorithm research of high-precision optical interferometric phase demodulation based on FPGA

    NASA Astrophysics Data System (ADS)

    Zhi, Chunxiao; Sun, Jinghua

    2012-11-01

    Optical interferometric phase demodulation algorithm is provided based on the principle of phase generated carrier (PGC), which can realize the optical interference measurement of high-precision signal demodulation, applied to optical fiber displacement, vibration sensor. Modulated photoelectric detection signal is performanced by interval 8 frequency multiplication sampling. The samples calculate the phase modulation depth and phase error through a feedback loop to achieve optimum working point control. On the other hand the results of sampling calculate precision of numerical of the phase. The algorithm uses the addition and subtraction method instead of correlation filtering and other related complex calculation process of the traditional PGC digital demodulation, making full use of FPGA data processing with advantage of high speed and parallel; This method can give full play to the advantage of FPGA performance. Otherwise, the speed at the same time, FPGA can also ensure that the phase demodulation precision, wide dynamic range, and give full play to the advantage of completing the data access by single clock cycle.

  10. Design, performance, and early results from extremely high Doppler precision instruments in a global network

    NASA Astrophysics Data System (ADS)

    Ge, Jian; Zhao, Bo; Groot, John; Chang, Liang; Varosi, Frank; Wan, Xiaoke; Powell, Scott; Jiang, Peng; Hanna, Kevin; Wang, Ji; Pais, Rohan; Liu, Jian; Dou, Liming; Schofield, Sidney; McDowell, Shaun; Costello, Erin; Delgado-Navarro, Adriana; Fleming, Scott; Lee, Brian; Bollampally, Sandeep R.; Bosman, Troy; Jakeman, Hali; Fletcher, Adam; Marquez, Gabriel

    2010-07-01

    We report design, performance and early results from two of the Extremely High Precision Extrasolar Planet Tracker Instruments (EXPERT) as part of a global network for hunting for low mass planets in the next decade. EXPERT is a combination of a thermally compensated monolithic Michelson interferometer and a cross-dispersed echelle spectrograph for extremely high precision Doppler measurements for nearby bright stars (e.g., 1m/s for a V=8 solar type star in 15 min exposure). It has R=18,000 with a 72 micron slit and a simultaneous coverage of 390-694 nm. The commissioning results show that the instrument has already produced a Doppler precision of about 1 m/s for a solar type star with S/N~100 per pixel. The instrument has reached ~4 mK (P-V) temperature stability, ~1 mpsi pressure stability over a week and a total instrument throughput of ~30% at 550 nm from the fiber input to the detector. EXPERT also has a direct cross-dispersed echelle spectroscopy mode fed with 50 micron fibers. It has spectral resolution of R=27,000 and a simultaneous wavelength coverage of 390-1000 nm.

  11. High Precision Oxygen Three Isotope Analysis of Wild-2 Particles and Anhydrous Chondritic Interplanetary Dust Particles

    NASA Technical Reports Server (NTRS)

    Nakashima, D.; Ushikubo, T.; Zolensky, Michael E.; Weisberg, M. K.; Joswiak, D. J.; Brownlee, D. E.; Matrajt, G.; Kita, N. T.

    2011-01-01

    One of the most important discoveries from comet Wild-2 samples was observation of crystalline silicate particles that resemble chondrules and CAIs in carbonaceous chondrites. Previous oxygen isotope analyses of crystalline silicate terminal particles showed heterogeneous oxygen isotope ratios with delta(sup 18)O to approx. delta(sup 17)O down to -50% in the CAI-like particle Inti, a relict olivine grain in Gozen-sama, and an olivine particle. However, many Wild-2 particles as well as ferromagnesian silicates in anhydrous interplanetary dust particles (IDPs) showed Delta(sup 17)O values that cluster around -2%. In carbonaceous chondrites, chondrules seem to show two major isotope reservoirs with Delta(sup 17)O values at -5% and -2%. It was suggested that the Delta(sup 17)O = -2% is the common oxygen isotope reservoir for carbonaceous chondrite chondrules and cometary dust, from the outer asteroid belt to the Kuiper belt region. However, a larger dataset with high precision isotope analyses (+/-1-2%) is still needed to resolve the similarities or distinctions among Wild-2 particles, IDPs and chondrules in meteorites. We have made signifi-cant efforts to establish routine analyses of small particles (< or =10micronsm) at 1-2% precision using IMS-1280 at WiscSIMS laboratory. Here we report new results of high precision oxygen isotope analyses of Wild-2 particles and anhydrous chondritic IDPs, and discuss the relationship between the cometary dust and carbonaceous chondrite chondrules.

  12. The high-precision videometrics methods to determining absolute vertical benchmark

    NASA Astrophysics Data System (ADS)

    Liu, Jinbo; Zhu, Zhaokun

    2013-01-01

    The mobile measurement equipment plays an important role in engineering measurement tasks and its measuring device is fixed with the vehicle platform. Therefore, how to correct the measured error in time that caused by swayed platform is a basic problem. Videometrics has its inherent advantages in solving this problem. First of all, videometrics technology is non-contact measurement, which has no effect on the target's structural characteristics and motion characteristics. Secondly, videometrics technology has high precision especially for surface targets and linear targets in the field of view. Thirdly, videometrics technology has the advantages of automatic, real-time and dynamic. This paper is mainly for mobile theodolite.etc that works under the environment of absolute vertical benchmark and proposed two high-precision methods to determine vertical benchmark: Direct-Extracting, which is based on the intersection of plats under the help of two cameras; Benchmark-Transformation, which gets the vertical benchmark by reconstructing the level-plat. Two methods both have the precision of under 10 seconds by digital simulation and physical experiments. The methods proposed by this paper have significance both on the theory and application.

  13. Rapid radiometric serum test for antibiotic activity.

    PubMed

    D'Antonio, R G; Camargo, E E; Gedra, T; Wagner, H N; Charache, P

    1982-02-01

    We have developed a 4-h radiometric method to predict the bacteriostatic endpoint by the tube dilution method. A mixture of [U-14C] glucose, [guanido-14C] arginine, and [U-14C] glycine was used to monitor the metabolic activity of both gram-positive and gram-negative organisms. The tube dilution method and the radiometric method were performed in parallel in 18 clinical serum samples. In the radiometric method, the samples were separated into control and test portions and serially diluted in Mueller-Hinton broth. Antibiotics in the control portion were inactivated with penicillinase or cellulose phosphate or both. The radioactive mixture and a 1-h culture of the patient's infecting organisms were added to all vials. The 14CO2 production after a 3-h incubation at 37 degrees C was measured, and the percent inhibition was determined for each vial by using the control vials as reference (no inhibition). Radiometric dose-response curves obtained for all samples showed that, by using a greater than or equal to 60% inhibition at 1:8 dilution, the radiometric method correctly predicted the outcome of the tube dilution method in 16 or 18 clinical samples.

  14. Interacting sources for high-precision atom interferometry - a theoretical study

    NASA Astrophysics Data System (ADS)

    Posso Trujillo, Katerine; Ahlers, Holger; Schubert, Christian; Ertmer, Wolfgang; Rasel, Ernst; Gaaloul, Naceur

    2014-05-01

    We theoretically study the possibilities to use binary quantum mixtures as sources for high-precision atom interferometers with interferometry times ranging over several seconds. Such schemes are of timely interest in the context of inertial navigation or fundamental physics laws tests. The mixture expansion dynamics are solved by integrating a set of two coupled Gross-Pitaevskii equations. In order to satisfy the severe requirements of a precise differential interferometer, a common delta-kick cooling stage is applied to the two ensembles simultaneously to induce ultra-slow expansion (~ 50 pk regime). Other systematic effects are analysed and mitigation strategies identified. To illustrate this study, we consider the case of three mixtures of 87Rb/85Rb, 87Rb/39Kand87Rb/41K widely used in atom interferometry measurements. The advantages and drawbacks of every pair are highlighted and discussed. K. Posso-Trujillo. thanks the German Academic Exchange Service - DAAD (research grant No. A/10/74250).

  15. The flare Package for High Dimensional Linear Regression and Precision Matrix Estimation in R

    PubMed Central

    Li, Xingguo; Zhao, Tuo; Yuan, Xiaoming; Liu, Han

    2016-01-01

    This paper describes an R package named flare, which implements a family of new high dimensional regression methods (LAD Lasso, SQRT Lasso, ℓq Lasso, and Dantzig selector) and their extensions to sparse precision matrix estimation (TIGER and CLIME). These methods exploit different nonsmooth loss functions to gain modeling exibility, estimation robustness, and tuning insensitiveness. The developed solver is based on the alternating direction method of multipliers (ADMM), which is further accelerated by the multistage screening approach. The package flare is coded in double precision C, and called from R by a user-friendly interface. The memory usage is optimized by using the sparse matrix output. The experiments show that flare is efficient and can scale up to large problems.

  16. Precision Measurement of the Proton Elastic Cross Section at High Q2

    NASA Astrophysics Data System (ADS)

    Ou, Longwu; E12-07-108 Collaboration

    2017-01-01

    The measurement of proton electromagnetic form factors (FF) is a powerful way to understand the internal structure of proton and gain insight into the nature of the strong interaction. Current data of FF at high Q2 have large statistical and systematic uncertainties, which translate into large uncertainties in the extracted cross section in this kinematic range. The GMp experiment in Hall A at Jefferson Lab, starting from 2014, performed precision measurements of elastic ep scattering cross section in the Q2 range from 7 to 14 (GeV / c) 2. These measurements will improve the precision on the cross section in the covered Q2 range to about 2 % . They represent a great complement to the world's cross section data set and will be key inputs for future electromagnetic form factor experiments at similar kinematics. In this talk, the instrumentation and techniques used in the experiment will be described, and the current status of the analysis will be presented.

  17. Limiting Energy Dissipation Induces Glassy Kinetics in Single-Cell High-Precision Responses.

    PubMed

    Das, Jayajit

    2016-03-08

    Single cells often generate precise responses by involving dissipative out-of-thermodynamic-equilibrium processes in signaling networks. The available free energy to fuel these processes could become limited depending on the metabolic state of an individual cell. How does limiting dissipation affect the kinetics of high-precision responses in single cells? I address this question in the context of a kinetic proofreading scheme used in a simple model of early-time T cell signaling. Using exact analytical calculations and numerical simulations, I show that limiting dissipation qualitatively changes the kinetics in single cells marked by emergence of slow kinetics, large cell-to-cell variations of copy numbers, temporally correlated stochastic events (dynamic facilitation), and ergodicity breaking. Thus, constraints in energy dissipation, in addition to negatively affecting ligand discrimination in T cells, can create a fundamental difficulty in determining single-cell kinetics from cell-population results. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  18. Limiting Energy Dissipation Induces Glassy Kinetics in Single-Cell High-Precision Responses

    PubMed Central

    Das, Jayajit

    2016-01-01

    Single cells often generate precise responses by involving dissipative out-of-thermodynamic-equilibrium processes in signaling networks. The available free energy to fuel these processes could become limited depending on the metabolic state of an individual cell. How does limiting dissipation affect the kinetics of high-precision responses in single cells? I address this question in the context of a kinetic proofreading scheme used in a simple model of early-time T cell signaling. Using exact analytical calculations and numerical simulations, I show that limiting dissipation qualitatively changes the kinetics in single cells marked by emergence of slow kinetics, large cell-to-cell variations of copy numbers, temporally correlated stochastic events (dynamic facilitation), and ergodicity breaking. Thus, constraints in energy dissipation, in addition to negatively affecting ligand discrimination in T cells, can create a fundamental difficulty in determining single-cell kinetics from cell-population results. PMID:26958894

  19. High-precision masses of neutron-deficient rubidium isotopes using a Penning trap mass spectrometer

    SciTech Connect

    Kellerbauer, A.; Audi, G.; Guenaut, C.; Lunney, D.; Beck, D.; Herfurth, F.; Kluge, H.-J.; Weber, C.; Yazidjian, C.; Blaum, K.; Bollen, G.; Schwarz, S.; Herlert, A.; Schweikhard, L.

    2007-10-15

    The atomic masses of the neutron-deficient radioactive rubidium isotopes {sup 74-77,79,80,83}Rb have been measured with the Penning trap mass spectrometer ISOLTRAP. Using the time-of-flight cyclotron resonance technique, relative mass uncertainties ranging from 1.6x10{sup -8} to 5.6x10{sup -8} were achieved. In all cases, the mass precision was significantly improved as compared with the prior Atomic-Mass Evaluation; no significant deviations from the literature values were observed. The exotic nuclide {sup 74}Rb, with a half-life of only 65 ms, is the shortest-lived nuclide on which a high-precision mass measurement in a Penning trap has been carried out. The significance of these measurements for a check of the conserved-vector-current hypothesis of the weak interaction and the unitarity of the Cabibbo-Kobayashi-Maskawa matrix is discussed.

  20. Precision roll-winding equipment for high-reliability liquid-filled plastic-film capacitors

    SciTech Connect

    Mauldin, G.H.; Reichenbach, M.L.; Sena, A.A.; Walter, J.K.S. Jr.

    1983-01-01

    Sandia National Laboratories has developed a precision capacitor-roll-winding technology which we believe is essential to high-reliability designs using plastic-film dielectrics. The need for this winding capability developed during the research and development phase of the perfluorocarbon-capacitor technology described earlier. It has been found during the research and development phase of this technology that a number of winding parameters are critical to the electrical performance of plastic-film capacitors. For example, controlling the looseness of the winding is critical to electrical performance. Small differences in looseness can result in orders of magnitude change in discharge life. Excessive wander of the extended aluminum foils creates a difficult electroding problem. This paper justifies the need for this precision winding technology, summarizes the features required, and describes two machine designs incorporating these features.

  1. Design of a Laser Ablation Ion Source for High-Precision Penning Trap Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Hunt, Curtis; Ratnayake, Ishara; Hawks, Paul; Bryce, Richard; Redshaw, Matthew

    2014-05-01

    High-precision atomic mass measurements provide important data for a wide range of fields including atomic, nuclear and neutrino physics, determination of fundamental constants, and metrology. At Central Michigan University we are building a Penning trap system that will utilize ions produced by external ion sources to allow access to a wide range of isotopes, including long-lived radioactive isotopes and isotopes with low natural abundances. The ions will be transported to a ``capture'' trap, before being transferred to double precision-measurement trap structure. In this poster we will present the design of a laser ablation ion source and the ion extraction and transport optics. We will report on the current status of the construction and operation of the ion source and the CMU Penning trap. This work supported in part by NSF award no. 1307233.

  2. High-precision machining of materials for manufacturing applications using diode-pumped solid state lasers

    NASA Astrophysics Data System (ADS)

    Nikumb, Suwas K.; Islam, M. U.

    2000-02-01

    While developments in the field of diode pumped solid state lasers provide a foundation for precision machining of parts with high accuracy and small feature sizes, this promise can not be realized without considering the interactions of individual processes, systems and material parameters. This paper presents our results on the precision machining of small features in various materials using diode pumped solid state lasers. The machined features are characterized geometrically by using optical inspection techniques and the tolerance data is analyzed statistically. Machining parameters relevant to motion system and tool path compensation are discussed along with their relevance to machined feature geometry. The effect of laser beam polarization on the machined kerf width, kerf surface and feature dimensions is reported.

  3. Using High Precision Stellar Observations to Constrain the Physics of Convection in Stars

    NASA Astrophysics Data System (ADS)

    Carleton, Timothy; Meakin, C.

    2011-05-01

    Arguably the most significant barrier to our full comprehension of stellar structure and evolution is the uncertainty in our understanding of stellar convection and its attendant mixing. Our current understanding of stellar convection, mixing length theory (MLT), describes convection as a process in which warmer pockets of fluid flow to the surface through a temperature gradient. The efficiency at which this transfers heat is dependent on the ratio of the surface area to the volume of the globule, gml. We use the stellar evolution simulation package MESA (Modules for Experiments in Stellar Astrophysics) together with new high precision observations of non-interacting binaries to constrain convection physics in low mass stars (M<1.2 Msun), specifically gml. Our data set contains 45 stars with precision mass, temperature and luminosity measurements (uncertainties at the few percent level) as well as observed relationships between turbulent surface velocity, surface gravity, and luminosity. This research was supported by the Arizona Space Grant Consortium.

  4. Towards a high-precision measurement of the antiproton magnetic moment

    NASA Astrophysics Data System (ADS)

    Smorra, C.; Blaum, K.; Franke, K.; Matsuda, Y.; Mooser, A.; Nagahama, H.; Ospelkaus, C.; Quint, W.; Schneider, G.; Van Gorp, S.; Walz, J.; Yamazaki, Y.; Ulmer, S.

    2014-02-01

    The recent observation of single spins flips with a single proton in a Penning trap opens the way to measure the proton magnetic moment with high precision. Based on this success, which has been achieved with our apparatus at the University of Mainz, we demonstrated recently the first application of the so called double Penning-trap method with a single proton. This is a major step towards a measurement of the proton magnetic moment with ppb precision. To apply this method to a single trapped antiproton our collaboration is currently setting up a companion experiment at the antiproton decelerator of CERN. This effort is recognized as the Baryon Antibaryon Symmetry Experiment (BASE). A comparison of both magnetic moment values will provide a stringent test of CPT invariance with baryons.

  5. What can we learn from high precision measurements of neutrino mixing angles?

    NASA Astrophysics Data System (ADS)

    Mohapatra, R. N.

    2004-12-01

    Many experiments are being planned to measure the neutrino mixing angles more precisely. In this note, the theoretical significance of a high precision measurement of these parameters is discussed. It is emphasized that they can provide crucial information about different ways to understand the origin of large atmospheric neutrino mixing and move us closer towards determining the neutrino mass matrix. They may also be able to throw light on the question of lepton-quark unification as well as the existence of any leptonic symmetries. For instance if exact m i symmetry in the neutrino mass matrix is assumed to be the reason for maximal nm-ni mixing, one gets q13 = 0 and theta_{13} simeq sqrt{Delta m_{dotcircle}^2/Delta_A^2} or theta_{13} simeq Delta m_{dotcircle}^2/Delta_A^2 can provide information about the way the m i symmetry breaking manifests in the case of normal hierarchy.

  6. Fabrication of high precision metallic freeform mirrors with magnetorheological finishing (MRF)

    NASA Astrophysics Data System (ADS)

    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.

  7. Computational Calorimetry: High-Precision Calculation of Host-Guest Binding Thermodynamics.

    PubMed

    Henriksen, Niel M; Fenley, Andrew T; Gilson, Michael K

    2015-09-08

    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.

  8. Computational Calorimetry: High-Precision Calculation of Host–Guest Binding Thermodynamics

    PubMed Central

    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

  9. Precision blood-leak detector with high long-time stability

    NASA Astrophysics Data System (ADS)

    Georgiadis, Christos; Kleuver, Wolfram

    1999-11-01

    With this publication a precision blood-leak-detector is presented. The blood-leak-detector is used for recognition of fractures in the dialyzer of a kidney-machine. It has to detect safely a blood flow of ml/min to exclude any risk for the patient. A lot of systems exist for blood-leak-detection. All of them use the same principle. They detect the light absorption in the dialyze fluid. The actual used detectors are inferior to the new developed sensor in resolution and long-time stability. Regular test of the existing systems and high failure rates are responsible for the high maintenance.

  10. High precision long-term stable fiber-based optical synchronization system

    NASA Astrophysics Data System (ADS)

    Li, Yurong; Wang, Xiaochao; Jiang, Youen; Qiao, Zhi; Li, Rao; Fan, Wei

    2016-10-01

    A fiber-based high precision long-term stable time synchronization system for multi-channel laser pulses is presented using fiber pulse stacker combined with high-speed optical-electrical conversion and electronics processing technology. This scheme is used to synchronize two individual lasers including a mode-lock laser and a time shaping pulse laser system. The relative timing jitter between two laser pulses achieved with this system is 970 fs (rms) in five minutes and 3.5 ps (rms) in five hours. The synchronization system is low cost and can work at over several tens of MHz repetition rate.

  11. Development of a custom high precision motion system to manipulate a 7 ton press

    NASA Astrophysics Data System (ADS)

    Deyhim, A.; Van Every, E.

    2013-03-01

    In this paper ADC will discuss the design and test results for a custom high precision motion system to manipulate a 7 ton press (fabricated by Rockland Research Corporation). The system was installed at Beamline X17B2 NSLS for High Pressure Mineral Physics research. The beamline contains 0.391 mm of graphite filters, .500 mm silicon filter, and 2.0 mm of beryllium windows. The experimental apparatus consists of a large volume (~1 cu mm) multi-anvil press in either cubic or octahedral mode, providing pressures up to 29 GPa and temperatures up to 2000 K.

  12. High-precision lattice calculation of the decay constants fB and fBs

    NASA Astrophysics Data System (ADS)

    Detar, Carleton; Bazavov, Alexei; Bernard, Claude; Bouchard, Christopher; Brown, Nathan; Du, Daping; El Khadra, Aida; Freeland, Elizabeth; Gamiz, Elvira; Gottlieb, Steven; Na, Heechang; Heller, Urs; Komijani, Javad; Kronfeld, Andreas; Laiho, John; MacKenzie, Paul; Neil, Ethan; Simone, James; Sugar, Robert; Toussaint, Douglas; van de Water, Ruth; Zhou, Ran; Fermilab Lattice Collaboration; MILC Collaboration

    2016-03-01

    We present preliminary, high-precision results for the hadronic decay constants of the B and the Bs mesons from lattice QCD simulations using a highly improved quark formulation for both heavy and light valence quarks. Calculations are carried out with several heavy valence-quark masses on lattice ensembles with 2+1+1 flavors of HISQ sea quarks at five lattice spacings and three light sea quark mass ratios mud /ms , including approximately physical sea quark masses. This range of parameters provides excellent control of the continuum limit and of heavy-quark discretization errors. Present affiliation: Ohio Supercomputer Center.

  13. Lightweight Metal Matrix Composite Segmented for Manufacturing High-Precision Mirrors

    NASA Technical Reports Server (NTRS)

    Vudler, Vladimir

    2012-01-01

    High-precision mirrors for space applications are traditionally manufactured from one piece of material, such as lightweight glass sandwich or beryllium. The purpose of this project was to develop and test the feasibility of a manufacturing process capable of producing mirrors out of welded segments of AlBeMet(Registered Trademark) (AM162H). AlBeMet(Registered Trademark) is a HIP'd (hot isostatic pressed) material containing approximately 62% beryllium and 38% aluminum. As a result, AlBeMet shares many of the benefits of both of those materials for use in high performance mirrors, while minimizing many of their weaknesses.

  14. Novel techniques for the analysis of the TOA radiometric uncertainty

    NASA Astrophysics Data System (ADS)

    Gorroño, Javier; Banks, Andrew; Gascon, Ferran; Fox, Nigel P.; Underwood, Craig I.

    2016-10-01

    In the framework of the European Copernicus programme, the European Space Agency (ESA) has launched the Sentinel-2 (S2) Earth Observation (EO) mission which provides optical high spatial -resolution imagery over land and coastal areas. As part of this mission, a tool (named S2-RUT, from Sentinel-2 Radiometric Uncertainty Tool) estimates the radiometric uncertainties associated to each pixel using as input the top-of-atmosphere (TOA) reflectance factor images provided by ESA. The initial version of the tool has been implemented — code and user guide available1 — and integrated as part of the Sentinel Toolbox. The tool required the study of several radiometric uncertainty sources as well as the calculation and validation of the combined standard uncertainty in order to estimate the TOA reflectance factor uncertainty per pixel. Here we describe the recent research in order to accommodate novel uncertainty contributions to the TOA reflectance uncertainty estimates in future versions of the tool. The two contributions that we explore are the radiometric impact of the spectral knowledge and the uncertainty propagation of the resampling associated to the orthorectification process. The former is produced by the uncertainty associated to the spectral calibration as well as the spectral variations across the instrument focal plane and the instrument degradation. The latter results of the focal plane image propagation into the provided orthoimage. The uncertainty propagation depends on the radiance levels on the pixel neighbourhood and the pixel correlation in the temporal and spatial dimensions. Special effort has been made studying non-stable scenarios and the comparison with different interpolation methods.

  15. Blast investigation by fast multispectral radiometric analysis

    NASA Astrophysics Data System (ADS)

    Devir, A. D.; Bushlin, Y.; Mendelewicz, I.; Lessin, A. B.; Engel, M.

    2011-06-01

    Knowledge regarding the processes involved in blasts and detonations is required in various applications, e.g. missile interception, blasts of high-explosive materials, final ballistics and IED identification. Blasts release large amount of energy in short time duration. Some part of this energy is released as intense radiation in the optical spectral bands. This paper proposes to measure the blast radiation by a fast multispectral radiometer. The measurement is made, simultaneously, in appropriately chosen spectral bands. These spectral bands provide extensive information on the physical and chemical processes that govern the blast through the time-dependence of the molecular and aerosol contributions to the detonation products. Multi-spectral blast measurements are performed in the visible, SWIR and MWIR spectral bands. Analysis of the cross-correlation between the measured multi-spectral signals gives the time dependence of the temperature, aerosol and gas composition of the blast. Farther analysis of the development of these quantities in time may indicate on the order of the detonation and amount and type of explosive materials. Examples of analysis of measured explosions are presented to demonstrate the power of the suggested fast multispectral radiometric analysis approach.

  16. SMILETRAP—A Penning trap facility for precision mass measurements using highly charged ions

    NASA Astrophysics Data System (ADS)

    Bergström, I.; Carlberg, C.; Fritioff, T.; Douysset, G.; Schönfelder, J.; Schuch, R.

    2002-07-01

    The precision of mass measurements in a Penning trap increases linearly with the charge of the ion. Therefore we have attached a Penning trap, named SMILETRAP, to the electron beam ion source CRYSIS at MSL. CRYSIS is via an isotope separator connected to an ion source that can deliver singly charged ions of practically any element. In CRYSIS charge state breeding occurs by intense electron bombardment. We have shown that it is possible to produce, catch and measure the cyclotron frequencies of ions in the charge region 1+ to 52+. The relevant observable in mass measurements using a Penning trap is the ratio of the cyclotron frequencies of the ion of interest and ion used as a mass reference. High precision requires that the two frequencies are measured after one another in the shortest possible time. For reasons of convenience the precision trap operates at room temperature. So far it has been believed that warm traps working at 4 K are required for high mass precision with exactly one ion in the trap at a time. In this paper we demonstrate that mass precision of a few parts in 10 10 also can be obtained in a warm trap at a pressure of about 5×10 -12 mbar by stabilizing the pressure in the He-dewar, the trap temperature and the frequency synthesizer. In order to reduce the influence of changes of the magnetic field to a level below 10 -10, the scanning of the frequencies close to the resonances of both the ion of interest and the reference ion is done in a total time <2 min. Trapping of ions is a statistical procedure, allowing more than one ion to be trapped in each measurement cycle. However, after completing the measurements it is possible to reject all information except for events based on 1 and 2 trapped ions. The procedures of producing, transporting, catching, exciting and measuring the cyclotron resonance frequencies of highly charged ions and the mass reference ions with the time-of-flight method are described. In routine measurements with 1 s excitation

  17. ACT3: A High-speed, High-Precision Electrical Impedance Tomograph

    PubMed Central

    Cook, Raymond D.; Saulnier, Gary J.; Gisser, David G.; Goble, John C.; Newell, JC.; Isaacson, David

    2016-01-01

    This paper presents the design, implementation, and performance of Rensselaer’s third-generation Adaptive Current Tomograph, ACT3. This system uses 32 current sources and 32 phase-sensitive voltmeters to make a 32-electrode system that is capable of applying arbitrary spatial patterns of current. The instrumentation provides 16 b precision on both the current values and the real and reactive voltage readings and can collect the data for a single image in 133 ms. Additionally, the instrument is able to automatically calibrate its voltmeters and current sources and adjust the current source output impedance under computer control. The major system components are discussed in detail and performance results are given. Images obtained using stationary agar targets and a moving pendulum in a phantom as well as in vivo resistivity profiles showing human respiration are shown. PMID:7927393

  18. High-precision orbit determination for high-earth elliptical orbiters using the Global Positioning System

    NASA Technical Reports Server (NTRS)

    Lichten, S. M.; Estefan, J. A.

    1990-01-01

    Orbit covariance analyses pertaining to the Japanese VLBI Space Observatory Program (VSOP) MUSES-B satellite and to the International VLBI Satellite are presented. It is determined that a combination of Doppler and GPS measurements can provide the orbit accuracy required to support advanced radio interferometric experiments. For the VSOP, the required orbit accuracy of 130 m is easily met with two-way Doppler as the primary type of data; the 0.4 cm/s VSOP velocity requirement is also feasible provided that precise ground calibrations of tropospheric delays and station coordinates are available. It is concluded that combining the data from a VSOP GPS flight instrument with the ground GPS and two-way Doppler data will significantly enhance orbit determination accuracy in position and velocity.

  19. Rapid radiometric susceptibility testing of Mycobacterium tuberculosis.

    PubMed

    Kertcher, J A; Chen, M F; Charache, P; Hwangbo, C C; Camargo, E E; McIntyre, P A; Wagner, H N

    1978-04-01

    A 48-hour radiometric test for determining the drug susceptibility of Mycobacterium tuberculosis has been developed. The test is based on the measurement of 14CO2 produced by the oxidation of formate labeled with carbon-14. The test system uses 5 X 10(7) organisms in 1 ml of Middlebrook 7H9 medium plus albumin-dextrose-catalase enrichment and 1 muCi of [14C]formate. The 14CO2 produced is measured in an ionization chamber at 24-, 48-, and 72-hour intervals, with and without the addition of antituberculous drugs. Isoniazid, streptomycin, rifampin, and ethambutol were each tested at 3 concentrations by the radiometric method and the reference (agar dilution) method. Six standard strains and 21 patient isolates were compared by both methods. Production of 14CO2 was quantitatively decreased in the presence of drugs that inhibit the organism. The radiometric method requires 2 days; the agar dilution, 14 to 21 days.

  20. A multi-channel radiometric profiler of temperature, humidity and cloud liquid.

    SciTech Connect

    Ware, R.; Carpenter, R.; Guldner, J.; Liljegren, J.; Nehrkorn, T.; Solheim, F.; Vandenberghe, F.; Environmental Research; Radiometrics Corp.; Univ. Corp. for Atmospheric Research; Weather Decision Technologies Inc.; Atmospheric and Environmental Research Inc.; National Center for Atmospheric Research

    2003-07-31

    A microwave radiometer is described that provides continuous thermodynamic (temperature, water vapor, and moisture) soundings during clear and cloudy conditions. The radiometric profiler observes radiation intensity at 12 microwave frequencies, along with zenith infrared and surface meteorological measurements. Historical radiosonde and neural network or regression methods are used for profile retrieval. We compare radiometric, radiosonde, and forecast soundings and evaluate the accuracy of radiometric temperature and water vapor soundings on the basis of statistical comparison with radiosonde soundings. We find that radiometric soundings are equivalent in accuracy to radiosonde soundings when used in numerical weather forecasting. A case study is described that demonstrates improved fog forecasting on the basis of variational assimilation of radiometric soundings. The accuracy of radiometric cloud liquid soundings is evaluated by comparison with cloud liquid sensors carried by radiosondes. Accurate high-resolution three-dimensional water vapor and wind analysis is described on the basis of assimilation of simulated thermodynamic and wind soundings along with GPS slant delays. Examples of mobile thermodynamic and wind profilers are shown. Thermodynamic profiling, particularly when combined with wind profiling and slant GPS, provides continuous atmospheric soundings for improved weather and dispersion forecasting.

  1. High-precision measurement of magnetic penetration depth in superconducting films

    SciTech Connect

    He, X.; Gozar, A.; Sundling, R.; Božović, I.

    2016-11-01

    We report that the magnetic penetration depth (λ) in thin superconducting films is usually measured by the mutual inductance technique. The accuracy of this method has been limited by uncertainties in the geometry of the solenoids and in the film position and thickness, by parasitic coupling between the coils, etc. Here, we present several improvements in the apparatus and the method. To ensure the precise thickness of the superconducting layer, we engineer the films at atomic level using atomic-layer-by-layer molecular beam epitaxy. In this way, we also eliminate secondary-phase precipitates, grain boundaries, and pinholes that are common with other deposition methods and that artificially increase the field transmission and thus the apparent λ. For better reproducibility, the thermal stability of our closed-cycle cryocooler used to control the temperature of the mutual inductance measurement has been significantly improved by inserting a custom-built thermal conductivity damper. Next, to minimize the uncertainties in the geometry, we fused a pair of small yet precisely wound coils into a single sapphire block machined to a high precision. Lastly, the sample is spring-loaded to exactly the same position with respect to the solenoids. Altogether, we can measure the absolute value of λ with the accuracy better than ±1%.

  2. High-precision measurement of magnetic penetration depth in superconducting films

    DOE PAGES

    He, X.; Gozar, A.; Sundling, R.; ...

    2016-11-01

    We report that the magnetic penetration depth (λ) in thin superconducting films is usually measured by the mutual inductance technique. The accuracy of this method has been limited by uncertainties in the geometry of the solenoids and in the film position and thickness, by parasitic coupling between the coils, etc. Here, we present several improvements in the apparatus and the method. To ensure the precise thickness of the superconducting layer, we engineer the films at atomic level using atomic-layer-by-layer molecular beam epitaxy. In this way, we also eliminate secondary-phase precipitates, grain boundaries, and pinholes that are common with other depositionmore » methods and that artificially increase the field transmission and thus the apparent λ. For better reproducibility, the thermal stability of our closed-cycle cryocooler used to control the temperature of the mutual inductance measurement has been significantly improved by inserting a custom-built thermal conductivity damper. Next, to minimize the uncertainties in the geometry, we fused a pair of small yet precisely wound coils into a single sapphire block machined to a high precision. Lastly, the sample is spring-loaded to exactly the same position with respect to the solenoids. Altogether, we can measure the absolute value of λ with the accuracy better than ±1%.« less

  3. High-precision measurement of magnetic penetration depth in superconducting films

    NASA Astrophysics Data System (ADS)

    He, X.; Gozar, A.; Sundling, R.; Božović, I.

    2016-11-01

    The magnetic penetration depth (λ) in thin superconducting films is usually measured by the mutual inductance technique. The accuracy of this method has been limited by uncertainties in the geometry of the solenoids and in the film position and thickness, by parasitic coupling between the coils, etc. Here, we present several improvements in the apparatus and the method. To ensure the precise thickness of the superconducting layer, we engineer the films at atomic level using atomic-layer-by-layer molecular beam epitaxy. In this way, we also eliminate secondary-phase precipitates, grain boundaries, and pinholes that are common with other deposition methods and that artificially increase the field transmission and thus the apparent λ. For better reproducibility, the thermal stability of our closed-cycle cryocooler used to control the temperature of the mutual inductance measurement has been significantly improved by inserting a custom-built thermal conductivity damper. Next, to minimize the uncertainties in the geometry, we fused a pair of small yet precisely wound coils into a single sapphire block machined to a high precision. The sample is spring-loaded to exactly the same position with respect to the solenoids. Altogether, we can measure the absolute value of λ with the accuracy better than ±1%.

  4. High-numerical-aperture cryogenic light microscopy for increased precision of superresolution reconstructions.

    PubMed

    Nahmani, Marc; Lanahan, Conor; DeRosier, David; Turrigiano, Gina G

    2017-04-11

    Superresolution microscopy has fundamentally altered our ability to resolve subcellular proteins, but improving on these techniques to study dense structures composed of single-molecule-sized elements has been a challenge. One possible approach to enhance superresolution precision is to use cryogenic fluorescent imaging, reported to reduce fluorescent protein bleaching rates, thereby increasing the precision of superresolution imaging. Here, we describe an approach to cryogenic photoactivated localization microscopy (cPALM) that permits the use of a room-temperature high-numerical-aperture objective lens to image frozen samples in their native state. We find that cPALM increases photon yields and show that this approach can be used to enhance the effective resolution of two photoactivatable/switchable fluorophore-labeled structures in the same frozen sample. This higher resolution, two-color extension of the cPALM technique will expand the accessibility of this approach to a range of laboratories interested in more precise reconstructions of complex subcellular targets.

  5. Multifrequency high precise subTHz-THz-IR spectroscopy for exhaled breath research

    NASA Astrophysics Data System (ADS)

    Vaks, Vladimir L.; Domracheva, Elena G.; Pripolzin, Sergey I.; Chernyaeva, Mariya B.

    2016-09-01

    Nowadays the development of analytical spectroscopy with high performance, sensitivity and spectral resolution for exhaled breath research is attended. The method of two-frequency high precise THz spectroscopy and the method of high precise subTHz-THz-IR spectroscopy are presented. Development of a subTHz-THz-IR gas analyzer increases the number of gases that can be identified and the reliability of the detection by confirming the signature in both THz and MIR ranges. The testing measurements have testified this new direction of analytical spectroscopy to open widespread trends of its using for various problems of medicine and biology. First of all, there are laboratory investigations of the processes in exhaled breath and studying of their dynamics. Besides, the methods presented can be applied for detecting intermediate and short time living products of reactions in exhaled breath. The spectrometers have been employed for investigations of acetone, methanol and ethanol in the breath samples of healthy volunteers and diabetes patients. The results have demonstrated an increased concentration of acetone in breath of diabetes patients. The dynamic of changing the acetone concentration before and after taking the medicines is discovered. The potential markers of pre-cancer states and oncological diseases of gastrointestinal tract organs have been detected. The changes in the NO concentration in exhaled breath of cancer patients during radiotherapy as well as increase of the NH3 concentration at gastrointestinal diseases have been revealed. The preliminary investigations of biomarkers in three frequency ranges have demonstrated the advantages of the multifrequency high precise spectroscopy for noninvasive medical diagnostics.

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

    SciTech Connect

    d'Enterria, David; Skands, Peter Z.

    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.

  7. A Detailed Radiometric Chronological Framework for Nordic Seas Ocean-Ice Sheet Interactions Spanning 50-150 Ka BP

    NASA Astrophysics Data System (ADS)

    Brendryen, J.; Edwards, R. L.; Haflidason, H.; Cheng, H.; Grasmo, K. J.; Sejrup, H. P.

    2014-12-01

    Chronological control of sedimentary deposits is a key to do paleoclimatic interpretations of proxy records and to compare them with records from other archives. Beyond the reach of radiocarbon dating there are however few options for developing chronological control. We present a detailed radiometrical-based chronological framework of a Norwegian Sea core archive that records ocean-ice sheet interactions in the Nordic Seas covering the time span 50-150 ka BP. The chronology is based on a detailed multi-proxy and multi-archive alignment of high resolution records from the Norwegian Sea and precisely radiometric dated speleothem δ18O record from both China and the Alps. This approach utilizes the close and well documented millennial and multi-centennial scale coupling between the North Atlantic climate variability (recorded in the Norwegian Sea records, the Greenland ice cores and in the Alpine speleothems) and the Asian Monsoon system recorded in the Chinese speleothem δ18O. One intriguing feature of the Norwegian Sea record is that it often is more similar to the Chinese speleothem records than to the Greenland ice core records. The alignment is aided by a tephrostratigraphic link to the Greenland ice cores which provide an independent test of the age model and alignment. Uncertainties are addressed by Bayesian age-depth modeling. The radiometric-based age model and the quantified uncertainties enable an independent comparison between the Nordic Seas ocean-ice sheet interaction and other absolutely dated records such as U/Th dated sea-level indices and orbital parameters. This improves our ability to interpret the ocean-ice sheet interactions of the polar north in a global context over this time span that comprises a glacial-interglacial cycle.

  8. High-precision determination of iron oxidation state in silicate glasses using XANES

    SciTech Connect

    Cottrell, Elizabeth; Kelley, Katherine A.; Lanzirotti, Antonio; Fischer, Rebecca A.

    2009-11-04

    Fe K-edge X-ray absorption near-edge structure (XANES) and Moessbauer spectra were collected on natural basaltic glasses equilibrated over a range of oxygen fugacity (QFM - 3.5 to QFM + 4.5). The basalt compositions and fO{sub 2} conditions were chosen to bracket the natural range of redox conditions expected for basalts from mid-ocean ridge, ocean island, back-arc basin, and arc settings, in order to develop a high-precision calibration for the determination of Fe{sup 3+}/{Sigma}Fe in natural basalts. The pre-edge centroid energy, corresponding to the 1s {yields} 3d transition, was determined to be the most robust proxy for Fe oxidation state, affording significant advantages compared to the use of other spectral features. A second-order polynomial models the correlation between the centroid and Fe{sup 3+}/{Sigma}Fe, yielding a precision of {+-} 0.0045 in Fe{sup 3+}/{Sigma}Fe for glasses with Fe{sup 3+}/{Sigma}Fe > 8%, which is comparable to the precision of wet chemistry. This high precision relies on a Si (311) monochromator to better define the Fe{sup 2+} and Fe{sup 3+} transitions, accurate and robust modeling of the pre-edge feature, dense fO{sub 2}-coverage and compositional appropriateness of reference glasses, and application of a non-linear drift correction. Through re-analysis of the reference glasses across three synchrotron beam sessions, we show that the quoted precision can be achieved (i.e., analyses are reproducible) across multiple synchrotron beam sessions, even when spectral collection conditions (detector parameters or sample geometry) change. Rhyolitic glasses were also analyzed and yield a higher centroid energy at a given Fe{sup 3+}/{Sigma}Fe than basalts, implying that major variations in melt structure affect the relationship between centroid position and Fe{sup 3+}/{Sigma}Fe, and that separate calibrations are needed for the determination of oxidation state in basalts and rhyolites.

  9. Indirect Terahertz Spectroscopy of Molecular Ions Using Highly Accurate and Precise Mid-Ir Spectroscopy

    NASA Astrophysics Data System (ADS)

    Mills, Andrew A.; Ford, Kyle B.; Kreckel, Holger; Perera, Manori; Crabtree, Kyle N.; McCall, Benjamin J.

    2009-06-01

    With the advent of Herschel and SOFIA, laboratory methods capable of providing molecular rest frequencies in the terahertz and sub-millimeter regime are increasingly important. As of yet, it has been difficult to perform spectroscopy in this wavelength region due to the limited availability of radiation sources, optics, and detectors. Our goal is to provide accurate THz rest frequencies for molecular ions by combining previously recorded microwave transitions with combination differences obtained from high precision mid-IR spectroscopy. We are constructing a Sensitive Resolved Ion Beam Spectroscopy setup which will harness the benefits of kinematic compression in a molecular ion beam to enable very high resolution spectroscopy. This ion beam is interrogated by continuous-wave cavity ringdown spectroscopy using a home-made widely tunable difference frequency laser that utilizes two near-IR lasers and a periodically-poled lithium niobate crystal. Here, we report our efforts to optimize our ion beam spectrometer and to perform high-precision and high-accuracy frequency measurements using an optical frequency comb. footnote

  10. Maintaining high precision of isotope ratio analysis over extended periods of time.

    PubMed

    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.

  11. AIRS radiometric calibration validation for climate research

    NASA Technical Reports Server (NTRS)

    Aumann, Hartmut H.; Pagano, Thomas S.; Elliott, Denis; Gaiser, Steve; Gregorich, Dave; Broberg, Steve

    2005-01-01

    Climate research using data from satellite based radiometers makes extreme demands on the traceability and stability of the radiometric calibration. The selection of a cooled grating array spectrometer for the Atmospheric Infrared Sounder, AIRS, is key, but does not ensured that AIRS data will be of climate quality. Additional design features, plus additional pre-launch testing, and extensive on-orbit calibration subsystem monitoring beyond what would suffice for application of the data to weather forecasting were required to ensure the radiometric data quality required for climate research. Validation that climate data quality are being generated makes use of the sea surface skin temperatures (SST and (obs-calc).

  12. High-Precision Marine Sr Isotope Geochronology in Deep Time: Permian Tuffs and Conodonts

    NASA Astrophysics Data System (ADS)

    Schmitz, M. D.; Davydov, V. I.; Snyder, W. S.

    2007-12-01

    Stratigraphic sections of the Southern Urals containing abundant and well-preserved fauna for precise biostratigraphic correlation and common instratified volcanic ash beds dated by U-Pb zircon geochronology offer a unique opportunity to constrain a temporally accurate Late Pennsylvanian-Early Permian seawater Sr curve. The 87Sr/86Sr compositions of conodonts (biogenic apatite) were measured by high-precision thermal ionization mass spectrometry following rigorous pretreatment protocols, and plotted within an age model calibrated by 13 high-precision U-Pb zircon ash bed ages. The resulting seawater Sr curve shows a significant reduction in data scatter by comparison to earlier curves (Denison et al., 1994; Veizer et al., 1999; Bruckschen et al., 1999; Korte et al., 2006), suggesting that our conodont pre-dissolution treatment was highly effective for retrieving the original seawater Sr signal. The relatively flat Late Moscovian through mid-Ghzelian seawater Sr curve of this study is generally consistent with that of Bruckschen et al. (1999). Beginning in the mid-Ghzelian, our data define a decreasing trend in 87Sr/86Sr through the mid-Sakmarian, consistent with the data of Korte et al. (2006). By combining our high precision 87Sr/86Sr measurements and U-Pb age calibration, the resolution of Sr isotope geochronology approaches 0.5 Ma in this interval. This highly resolved seawater 87Sr/86Sr record obtained for the Late Moscovian through mid-Sakmarian will aid in global carbonate chemostratigraphic correlation and contribute to our understanding of the timing of Late Paleozoic glacial and tectonic events. References: Bruckschen, P., Oesmann, S., Veizer, J., 1999. Isotope stratigraphy of the European Carboniferous: proxy signals for ocean chemistry, climate and tectonics. Chemical Geology 161, p. 127-163. Denison, R.E., Koepnick, R.B., Burke, W.H., Hetherington, E.A., Fletcher, A., 1994. Construction of the Mississippian, Pennsylvanian and Permian seawater 87Sr/86Sr

  13. High-Precision Distribution of Highly Stable Optical Pulse Trains with 8.8 × 10−19 instability

    PubMed Central

    Ning, B.; Zhang, S. Y.; Hou, D.; Wu, J. T.; Li, Z. B.; Zhao, J. Y.

    2014-01-01

    The high-precision distribution of optical pulse trains via fibre links has had a considerable impact in many fields. In most published work, the accuracy is still fundamentally limited by unavoidable noise sources, such as thermal and shot noise from conventional photodiodes and thermal noise from mixers. Here, we demonstrate a new high-precision timing distribution system that uses a highly precise phase detector to obviously reduce the effect of these limitations. Instead of using photodiodes and microwave mixers, we use several fibre Sagnac-loop-based optical-microwave phase detectors (OM-PDs) to achieve optical-electrical conversion and phase measurements, thereby suppressing the sources of noise and achieving ultra-high accuracy. The results of a distribution experiment using a 10-km fibre link indicate that our system exhibits a residual instability of 2.0 × 10−15 at1 s and8.8 × 10−19 at 40,000 s and an integrated timing jitter as low as 3.8 fs in a bandwidth of 1 Hz to 100 kHz. This low instability and timing jitter make it possible for our system to be used in the distribution of optical-clock signals or in applications that require extremely accurate frequency/time synchronisation. PMID:24870442

  14. Optical vortex beam based optical fan for high-precision optical measurements and optical switching.

    PubMed

    Zhou, Zhi-Yuan; Li, Yan; Ding, Dong-Sheng; Zhang, Wei; Shi, Shuai; Shi, Bao-Sen

    2014-09-01

    The polarization and orbital angular momentum properties of light are of great importance in optical science and technology in the fields of high-precision optical measurements and high-capacity and high-speed optical communications. Here we show a method for the construction of a simple and robust scheme to rotate a light beam such as a fan, which is based on a combination of these two properties and using the thermal-dispersion and electro-optical effect of birefringent crystals. Using a computer-based digital image-processing technique, we determine the temperature and thermal-dispersion difference of the crystal with high resolution. We also use the rotation phenomenon to realize thermo-optic and electro-optic switches. The basic operating principles for measurement and switching processes are presented in detail. The methods developed here will have wide practical applicability in various fields, including remote sensing, materials science, and optical communication networks.

  15. High-Precision Dispensing of Nanoliter Biofluids on Glass Pedestal Arrays for Ultrasensitive Biomolecule Detection.

    PubMed

    Chen, Xiaoxiao; Liu, Yang; Xu, QianFeng; Zhu, Jing; Poget, Sébastien F; Lyons, Alan M

    2016-05-04

    Precise dispensing of nanoliter droplets is necessary for the development of sensitive and accurate assays, especially when the availability of the source solution is limited. Conventional approaches are limited by imprecise positioning, large shear forces, surface tension effects, and high costs. To address the need for precise and economical dispensing of nanoliter volumes, we developed a new approach where the dispensed volume is dependent on the size and shape of defined surface features, thus freeing the dispensing process from pumps and fine-gauge needles requiring accurate positioning. The surface we fabricated, called a nanoliter droplet virtual well microplate (nVWP), achieves high-precision dispensing (better than ±0.5 nL or ±1.6% at 32 nL) of 20-40 nL droplets using a small source drop (3-10 μL) on isolated hydrophilic glass pedestals (500 μm on a side) bonded to arrays of polydimethylsiloxane conical posts. The sharp 90° edge of the glass pedestal pins the solid-liquid-vapor triple contact line (TCL), averting the wetting of the glass sidewalls while the fluid is prevented from receding from the edge. This edge creates a sufficiently large energy barrier such that microliter water droplets can be poised on the glass pedestals, exhibiting contact angles greater >150°. This approach relieves the stringent mechanical alignment tolerances required for conventional dispensing techniques, shifting the control of dispensed volume to the area circumscribed by the glass edge. The effects of glass surface chemistry and dispense velocity on droplet volume were studied using optical microscopy and high-speed video. Functionalization of the glass pedestal surface enabled the selective adsorption of specific peptides and proteins from synthetic and natural biomolecule mixtures, such as venom. We further demonstrate how the nVWP dispensing platform can be used for a variety of assays, including sensitive detection of proteins and peptides by fluorescence

  16. Uplift and Exhumation Rate of High-Pressure Metaophiolite Units From Nw-Alps (Italy): Radiometric Constraints from the Voltri Group and the Tertiary Piemontese Basin

    NASA Astrophysics Data System (ADS)

    Federico, L.; Crispini, L.; Capponi, G.; Scambelluri, M.; Villa, I. M.

    2003-04-01

    The Voltri Massif metaophiolites (Ligurian Western Alps) underwent alpine high-pressure metamorphism (550^oC, 18-19 kbar) and are overlain by late to post-orogenic conglomerates of Tertiary Piedmontese Basin (TPB). Combined 39Ar/40Ar step-heating dating and electron microprobe studies of high pressure phengites from the Voltri eclogite to blueschist-facies metabasites and metasediments and from eclogite clasts of the TPB conglomerates were performed to date the high-pressure metamorphism in rocks from these two settings. The basal conglomerates of the TPB were paleontologically dated at the Lower Oligocene (around 30 Ma). As very young ages, in part overlapping to Lower Oligocene, have recently been obtained for the high-pressure metamorphism in the Western Alps (Duchêne et al. 1997; Gebauer et al. 1997; Tilton et al. 1991) and in the Voltri Massif itself (34±1 Ma; Rubatto &Scambelluri, 2002), the comparison between the age of high-pressure metamorphism of belt eclogites and of eclogite clasts in sediments is particularly intriguing to constrain the tectonic history of uplift and exhumation of these rocks. Phengites from the eclogite clasts display homogeneous Si4+contents up to 7.38 p.f.u. All analyzed micas of the Voltri mafic rocks correspond to blueschist-facies phengites with Si4+ ranging between 7.16 and 6.63 p.f.u. Two Voltri metasediments contain partially retrogressed micas with Si4+ 7.66-6.30 p.f.u. We obtained 39Ar/40Ar ages of 48.7±0.4 Ma for the eclogite clast, a younger age of 40.0±0.4 Ma for the blueschist phengites. The metasediments are characterized by more disturbed argon release spectra; nevertheless they suggest an event older than 46-47 Ma, followed by a greenschist facies stage, at about 33 Ma or younger. These new data support an age of 48-49 Ma for the high-pressure event in the Ligurian Alps. As eclogite clasts are embedded in 30 Ma old conglomerates, the high-pressure rocks have been exhumed from ca. 63 Km in about 19 Ma, suggesting

  17. A High Precision Scanning Control System For A VUV Fourier Transform Spectrometer

    SciTech Connect

    De Oliveira, N.; Nahon, L.; Polack, F.; Joyeux, D.; Phalippou, D.; Rodier, J. C.; Vervloeet, M.

    2007-01-19

    A VUV Fourier transform spectrometer based on a wavefront division interferometer has been built. Our ultimate goal is to provide a high resolution absorption spectrometer in the 140 - 40 nm range using the new third generation French synchrotron source Soleil as the background continuum. Here, we present the design and latest performance of the instrument scanning control system. It is based on multiple reflections of a monomode, frequency-stabilized HeNe laser between two plane mirrors allowing the required sensitivity on the displacement of the interferometer mobile arm. The experimental results on the sampling precision show an rms error below 5 nm for a travel length of 7.5 mm.

  18. Development of laser interferometric high-precision geometry monitor for JASMINE

    NASA Astrophysics Data System (ADS)

    Niwa, Yoshito; Arai, Koji; Ueda, Akitoshi; Sakagami, Masaaki; Gouda, Naoteru; Kobayashi, Yukiyasu; Yamada, Yoshiyuki; Yano, Taihei

    2008-07-01

    The telescope geometry of JASMINE should be stabilized and monitored with the accuracy of about 10 to 100 picometer or 10 to 100 picoradian in root-mean-square over about 10 hours. For this purpose, a high-precision interferometric laser metrology system is employed. One of useful techniques for measuring displacements in extremely minute scales is the heterodyne interferometrical method. Experiment for verification of multi degree of freedom measurement was performed and mirror motions were successfully monitored with three degree of freedom.

  19. Precise Access to the Molecular-Frame Complex Recombination Dipole through High-Harmonic Spectroscopy

    NASA Astrophysics Data System (ADS)

    Schoun, S. B.; Camper, A.; Salières, P.; Lucchese, R. R.; Agostini, P.; DiMauro, L. F.

    2017-01-01

    We report on spectral intensity and group delay measurements of the highest-occupied molecular-orbital (HOMO) recombination dipole moment of N2 in the molecular-frame using high harmonic spectroscopy. We take advantage of the long-wavelength 1.3 μ m driving laser to isolate the HOMO in the near threshold region, 19-67 eV. The precision of our group delay measurements reveals previously unseen angle-resolved spectral features associated with autoionizing resonances, and allows quantitative comparison with cutting-edge correlated 8-channel photoionization dipole moment calculations.

  20. High-precision resistance measurements on amorphous CuTi down to 15 mK

    NASA Astrophysics Data System (ADS)

    Fan, R.; Pratt, W. P., Jr.; Greig, D.

    1992-11-01

    We have developed a new method for making high-precision resistance measurements on amorphous-metal ribbons with very reliable thermometry down to 15 mK. In our technique the measuring current flows perpendicular to the plane of the metal ribbon and potassium metal is used to thermally anchor the ribbon to the thermometers and refrigerator. We have been able to obtain very good fits of the weak-localization and enhanced electron-electron interaction theories to the CuTi data in zero field.