Sample records for vi ccd photometry

  1. Southern Clusters for Standardizing CCD Photometry (United States)

    Moon, T. T.


    Standardizing photometric measurements typically involves undertaking all-sky photometry. This can be laborious and time-consuming and, for CCD photometry, particularly challenging. Transforming photometry to a standard system is, however, a crucial step when routinely measuring variable stars, as it allows photoelectric measurements from different observers to be combined. For observers in the northern hemisphere, standardized UBVRI values of stars in open clusters such as M67 and NGC 7790 have been established, greatly facilitating quick and accurate transformation of CCD measurements. Recently the AAVSO added the cluster NGC 3532 for southern hemisphere observers to similarly standardize their photometry. The availability of NGC 3532 standards was announced on the AAVSO Variable Star Observing, Photometry forum on 27 October 2016. Published photometry, along with some new measurements by the author, provide a means of checking these NGC 3532 standards which were determined through the AAVSO's Bright Star Monitor (BSM) program (see: New measurements of selected stars in the open clusters M25 and NGC 6067 are also included.

  2. CCD Photometry of bright stars using objective wire mesh

    Energy Technology Data Exchange (ETDEWEB)

    Kamiński, Krzysztof; Zgórz, Marika [Astronomical Observatory Institute, Faculty of Physics, A. Mickiewicz University, Słoneczna 36, 60-286 Poznań (Poland); Schwarzenberg-Czerny, Aleksander, E-mail: [Copernicus Astronomical Centre, ul. Bartycka 18, PL 00-716 Warsaw (Poland)


    Obtaining accurate photometry of bright stars from the ground remains problematic due to the danger of overexposing the target and/or the lack of suitable nearby comparison stars. The century-old method of using objective wire mesh to produce multiple stellar images seems promising for the precise CCD photometry of such stars. Furthermore, our tests on β Cep and its comparison star, differing by 5 mag, are very encouraging. Using a CCD camera and a 20 cm telescope with the objective covered by a plastic wire mesh, in poor weather conditions, we obtained differential photometry with a precision of 4.5 mmag per two minute exposure. Our technique is flexible and may be tuned to cover a range as big as 6-8 mag. We discuss the possibility of installing a wire mesh directly in the filter wheel.

  3. Multiband CCD Photometry of CY Aquarii Using the AAVSOnet (United States)

    Cowall, D. E.


    delta Scuti stars are a class of short-period pulsating variable stars that include CY Aquarii. Multiband CCD photometry was performed on that star using instruments in Massachusetts, New Mexico, and Australia from the AAVSO's global robotic telescope network. Rapid cadence, multi-hour time series yielded high precision light curves and 21 new maxima. Data analyses revealed a pulsation pattern consistent with the existing model that describes the origin of SXPHE stars.

  4. DOPHOT, a CCD photometry program: Description and tests (United States)

    Schechter, Paul L.; Mateo, Mario; Saha, Abhijit


    The design considerations and operational features of DOPHOT, a point-spread function (PSF) fitting photometry program, are described. Some relevant details of the PSF fitting are discussed. The quality of the photometry returned by DOPHOT is assessed via reductions of an 'artificial' globular cluster generated from a list of stars with known magnitudes and colors. Results from comparative tests between DOPHOT and DAOPHOT using this synthetic cluster and real data are also described.

  5. Jonckheere Double Star Photometry - Part VI: Auriga (United States)

    Knapp, Wilfried


    If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part of them has magnitudes which are obviously far too bright. This report covers the Jonckheere objects in the constellation Auriga. Only one image per object was taken as despite the risk of random effects even a single instance visual magnitude measurement is better than the currently usually given estimation although the J-objects in this constellation seem with some exceptions better covered with observations as usual for Jonckheere doubles.

  6. Autoguiding and Defocus Experiments for CCD Differential Photometry (United States)

    Sturm, E. J.


    A number of smaller observatories utilize relatively low-cost, off-the-shelf telescopes and CCD cameras to obtain differential photometric measurements of variable stars. Obtaining the best-possible differential photometric precision, as evidenced by the standard deviations of the comparison-check differentials, is often a vital goal. This series of experiments is investigating, for two different Meade LX-200 telescopes (each equipped with an SBIG ST-7XE camera), the relationship between: (1) autoguiding precision and differential photometric precision, and (2) focus precision and differential photometric precision. The effects of purposefully introducing both autoguiding "errors" (i.e. small telescope movements) and image defocus on differential photometric precision are being evaluated. Telescope time is being provided by the Orion and Dark Ridge Observatories. I acknowledge the assistance of Russell Genet (Orion Observatory), Thomas Smith (Dark Ridge Observatory), and John Mottmann (California Polytechnic State University), as well as the financial support by the Department of Physics, California Polytechnic State University for conference and travel expenses.

  7. An Intensive CCD Photometry Campaign to Observe DW Ursae Majoris (United States)

    Boyd, David; Gaensicke, Boris


    We report on a coordinated observing campaign in April and May 2008 to study the eclipsing dwarf nova DW Ursae Majoris. This belongs to the group of SW Sex stars, nova-like variables containing accretion disks which exhibit superhumps in their light curves suggesting that their accretion disks are elliptical and precessing on time scales of a few days due to tidal interactions with the companion star. It has been suggested that the changing geometry will cause the depth of eclipses to be modulated on the accretion disk precession period. The aim of this campaign was to provide for the first time sufficient continuous photometric coverage of an eclipsing super-humper to test this hypothesis. 26 experienced amateur CCD photometrists in 7 countries participated in the project and altogether made almost 55,000 magnitude measurements over a 4 week period, keeping DW UMa under observation for more than 50% of the time. The results provide direct measurements of the orbital, super-hump and disk precession periods, confirming unambiguously that the superhump signal is a beat between the orbital and precession periods. They also reveal modulation not only of the eclipse depth but also of the eclipse time of minimum and width on the accretion disk precession period. The project is a good example of cooperation between the amateur and professional communities to address an open research issue.

  8. Employing the Technology of Virtual Observatory as the Fundamental Framework for the CCD Photometry Survey (United States)

    Škoda, P.; Hroch, F.; Nádvorník, J.; Mikhailova, D.


    The project of Ondřejov Southern Photometry Survey (OSPS) is an attempt to exploit the wealth of temporal information contained in multi-colour CCD photometry obtained with 1.54m Danish telescope at La Silla in remote observing mode by several groups of Czech astronomers working on different scientific programs and various primary targets. The OSPS realizes the idea of an automatic extraction of multi-colour light curves from every celestial object identified in the frame, thus giving access to 99% of data normally disposed by the PI's, who usually measure only few targets in every CCD frame. The Virtual Observatory (VO) technology is exploited here as an integral part of previewing, data reduction, bookkeeping, method of analysis and publishing.

  9. CCD Photometry of Field RR Lyrae Stars. I. Period Changes of SV ERI and XX and

    Directory of Open Access Journals (Sweden)

    Jong-Myung Joo


    Full Text Available CCD time series photometry was performed for two Oosterhoff type II± field RR Lyrae stars, SV Eri and XX And, to construct light curves in B and V bands. The maximum light times from our observations were combined with those in the literature to construct phase shift diagrams, from which we determined the period change rates β. We obtained large positive period change rates for these stars, which are expected from current evolutionary models if these stars are evolving rapidly from blue to red toward the end of core helium burning phase.

  10. CCD photometry in the Vilnius photometric systems. II. Analysis of a region in Lyra

    Energy Technology Data Exchange (ETDEWEB)

    Smriglio, F.; Dasgupta, A.K. (Rome Univ. (IT). Ist. Astronomico); Nandy, K. (Royal Observatory, Edinburgh (UK)); Boyle, R.P. (Vatican Observatory, Rome (IT)); Straizys, V.; Janulis, R. (AN Litovskoj SSR, Vilnius (SU). Inst. Fiziki)


    Two-dimensional classification of 216 stars down to 17 mag based on their seven color photoelectric and CCD photometry in the Vilnius system is presented. Except for normal stars, several subdwarfs, metal-deficient giants, and stars of other peculiarities are suspected. Interstellar extinction is determined for normal stars in two areas north and south of globular cluster M56, as well as for a 1 square degree area around M56. The mean value of A{sub v} outside the galactic dust layer is {similar to} 0.75 mag.

  11. Direct measurement and calibration of the Kepler CCD Pixel Response Function for improved photometry and astrometry (United States)

    Ninkov, Zoran

    Stellar images taken with telescopes and detectors in space are usually undersampled, and to correct for this, an accurate pixel response function is required. The standard approach for HST and KEPLER has been to measure the telescope PSF combined ("convolved") with the actual pixel response function, super-sampled by taking into account dithered or offset observed images of many stars (Lauer [1999]). This combined response function has been called the "PRF" (Bryson et al. [2011]). However, using such results has not allowed astrometry from KEPLER to reach its full potential (Monet et al. [2010], [2014]). Given the precision of KEPLER photometry, it should be feasible to use a pre-determined detector pixel response function (PRF) and an optical point spread function (PSF) as separable quantities to more accurately correct photometry and astrometry for undersampling. Wavelength (i.e. stellar color) and instrumental temperature should be affecting each of these differently. Discussion of the PRF in the "KEPLER Instrument Handbook" is limited to an ad-hoc extension of earlier measurements on a quite different CCD. It is known that the KEPLER PSF typically has a sharp spike in the middle, and the main bulk of the PSF is still small enough to be undersampled, so that any substructure in the pixel may interact significantly with the optical PSF. Both the PSF and PRF are probably asymmetric. We propose to measure the PRF for an example of the CCD sensors used on KEPLER at sufficient sampling resolution to allow significant improvement of KEPLER photometry and astrometry, in particular allowing PSF fitting techniques to be used on the data archive.

  12. CCD Photometry of Six Asteroids from the Universidad de Monterry Observatory (United States)

    Sada, Pedro V.


    CCD photometry of six asteroids was obtained at the Universidad de Monterrey Observatory during January and February 2008. The resulting synodic rotation periods and amplitudes are as follows: 1292 Luce, 6.9541 ± 0.0002 h, 0.20 ± 0.01 mag; 1303 Luthera, 5.878 ± 0.003 h, 0.08 ± 0.01 mag; 1900 Katyusha, 9.4999 ± 0.0001 h, 0.72 ± 0.02 mag, 2807 Karl Marx, 8.842 ± 0.001 h, 0.40 ± 0.05 mag; 3409 Abramov, 7.791 ± 0.002 h, 0.55 ± 0.02 mag; and 9117 Aude, 2.8156 ± 0.0001 h, 0.20 ± 0.01 mag.

  13. Two-Color VR CCD Photometry of Old Nova V603 Aquilae

    Directory of Open Access Journals (Sweden)

    Ivan L. Andronov


    Full Text Available Results of 6 nights of CCD VR photometry of the nova-like variable V603 Aquilae (Nova Aquilae 1918 obtained at the Mallorcian 35-cm telescope in July 2004 are reported. The ephemeris for the superhump maximum is Max.HJD=2453213.60546(96 +0.14813(10E. The waves with 3.9d, 1.4d, 0.135d are statistically significant, which may be interpreted as the negative superhump-orbital, the beat periods (negative superhump - positive superhump and the negative superhump with low amplitude, respectively. Another possible time-scale is 0.8d, which has no coincidence with the beat periods. Quasi-periodic oscillations with an effective period of 18 minutes have been detected, which are close to 15.6 minutes reported by some authors. Their effective semi-amplitudes are 0.045m and 0.051m for V and R, respectively. This corresponds to the 0.12 mag excess in the color index V-R as compared with the mean color, which can be understood as the pulsed emission in the hotter inner parts of the accretion disk, similar to that observed in TT Ari and MV Lyr.

  14. VizieR Online Data Catalog: NGC 6811 CCD UBVRI photometry (Yontan+, 2015) (United States)

    Yontan, T.; Bilir, S.; Bostanc, Z. F.; Ak, T.; Karaali, S.; Guver, T.; Ak, S.; Duran, S.; Paunzen, E.


    CCD UBVRI observations of NGC 6811 were carried out on 18th July 2012 using the 1m Ritchey-Chretien telescope (T100) located at the TUBITAK National Observatory (TUG) in Bakirlitepe, Antalya/Turkey. (1 data file).

  15. VizieR Online Data Catalog: NGC 6819 CCD UBV photometry (Ak+, 2016) (United States)

    Ak, T.; Bostanci, Z. F.; Yontan, T.; Bilir, S.; Guver, T.; Ak, S.; Urgup, H.; Paunzen, E.


    CCD UBVRI images of the open cluster NGC 6819 and standard stars selected from Landolt (2009, Cat. J/AJ/137/4186) were acquired on 2015 May 18 using a 1-m Ritchey-Chretien telescope (T100) located at the TUBITAK National Observatory (TUG) in Bakirlitepe, Antalya/Turkey. (1 data file).

  16. VizieR Online Data Catalog: NGC 225 CCD UBV photometry (Bilir+, 2016) (United States)

    Bilir, S.; Bostanci, Z. F.; Yontan, T.; Guver, T.; Bakis, V.; Ak, T.; Ak, S.; Paunzen, E.; Eker, Z.


    CCD UBVRI images of the open cluster NGC 225 and standard stars selected from Landolt (2009, Cat. J/AJ/137/4186) were acquired on 2012 July 18 using a 1-m Ritchey-Chretien telescope (T100) located at the TUBITAK National Observatory (TUG) in Bakirlitepe, Antalya/Turkey. (1 data file).

  17. UPYZVS CCD-photometry for the IC 4665 open cluster sky area (Andrushivka AO). (United States)

    Andruk, V.; Bartashiute, S.; Butenko, G.; Gerashchenko, O.; Ivashchenko, Yu.; Kovalchuk, G.; Lokot', V.; Perekhod, A.; Samoylov, V.


    CCD observations of four sky area in the IC 4665 open cluster were made to examine the Zeiss-600 telescope photometric system (the Andrushivka AO, Ukraine) with the aim of the Vilnius system implementation. Magnitudes and coordinates of stars up to V=15.m6 were determinate for 23'.5x23'.5 overlapping fields. Equatorial coordinates of stars were obtained in the USNO-A2.0 catalog system. The CCD frame processing method is describe. It is based on a new technique for flat field elumination with the MIDAS/ROMAFOT software (the LINUX shell). The rms error of single determination of magnitude for the stars up to V=13m is ±0m.02/0m.03 for 60 s exposure. The photometric system of the telescope the UPYZVS Vilnius system is determined; the reduction accuracy is 0m.02/0m.10.

  18. Two-Color VR CCD Photometry of the Intermediate Polar 1RXS J062518.2+733433

    Directory of Open Access Journals (Sweden)

    Yonggi Kim


    Full Text Available Results of 7 nights of CCD VR photometry of the intermediate polar 1RXS J062518.2 +733433 obtained at the Korean 1.8m telescope are reported. The corrected ephemeris for the orbital minimum is BJD (Orb.min = 2453023.6159 (42+0.1966431 (33 (E- 1735. The corrected ephemeris for the spin maximum is BJD (spin max = 2452893 .78477 (10+0.01374116815 (17 (E-15382 (cycle numbering corresponds to that of Staude et al.~2003. The variations of the shape of the individual spin variations are highly correlated in V and R. The phase of the spin maximum is found to be dependent on the orbital phase. The corresponding semi-amplitude of sinusoidal variations of phase is 0.11±0.03. This new phenomenon is explained by the changing viewing conditions of the accreting magnetic white dwarf, and should be checked in further observations this star and for other intermediate polars. To avoid influence of this effect on the analysis of the long-term spin period variations, the runs of at least one orbital period are recommended. Results of time series analysis are presented in tables.

  19. Kottamia 74-inch telescope discovery of the new eclipsing binary 2MASS J20004638 + 0547475.: First CCD photometry and light curve analysis (United States)

    Darwish, M. S.; Shokry, A.; Saad, S. M.; El-Sadek, M. A.; Essam, A.; Ismail, M.


    A CCD photometric study is presented for the eclipsing binary system 2MASS J20004638 + 0547475. Observations of the system were obtained in the V, R and I colours with the 2Kx2K CCD attached to 1.88 m Kottamia Optical Telescope. New times of light minimum and new ephemeris were obtained. The V, R and I light curves were analyzed using the PHOEBE 0.31 program to determine geometrical and physical parameters of the system. The results show that 2MASS J20004638 + 0547475, is A-Type WUMa and is an overcontact binary with high fill-out factor = 69%. The current evolutionary status of the system indicates that the primary component lies very close to the main sequence while the secondary is evolved. The asymmetric maxima were studied and a modeling of the hot spot parameters is given.

  20. High frame rate imaging based photometry

    DEFF Research Database (Denmark)

    Harpsøe, Kennet Bomann West; Jørgensen, Uffe Gråe; Andersen, Michael Ingemann


    an EMCCD is not normally distributed. Also, the readout process generates spurious charges in any CCD, but in EMCCD data, these charges are visible as opposed to the conventional CCD. Furthermore we aim to eliminate the photon waste associated with lucky imaging by combining this method with shift...... of the photometry, corrected frames of a crowded field are reduced with a PSF fitting photometry package, where a lucky image is used as a reference. We find that it is possible to develop an algorithm that elegantly reduces EMCCD data and produces stable photometry at the 1% level in an extremely crowded field....

  1. CCD Camera (United States)

    Roth, Roger R.


    A CCD camera capable of observing a moving object which has varying intensities of radiation eminating therefrom and which may move at varying speeds is shown wherein there is substantially no overlapping of successive images and wherein the exposure times and scan times may be varied independently of each other.

  2. Asteroid photometry (United States)

    Li, Jian-Yang; Helfenstein, Paul; Buratti, Bonnie J.; Takir, Driss; Beth Ellen Clark,; Michel, Patrick; DeMeo, Francesca E.; Bottke, William F.


    Asteroid photometry has three major applications: providing clues about asteroid surface physical properties and compositions, facilitating photometric corrections, and helping design and plan ground-based and spacecraft observations. The most significant advances in asteroid photometry in the past decade were driven by spacecraft observations that collected spatially resolved imaging and spectroscopy data. In the mean time, laboratory measurements and theoretical developments are revealing controversies regarding the physical interpretations of models and model parameter values. We will review the new developments in asteroid photometry that have occurred over the past decade in the three complementary areas of observations, laboratory work, and theory. Finally we will summarize and discuss the implications of recent findings.

  3. CCD Parallaxes for 309 Late-type Dwarfs and Subdwarfs

    Energy Technology Data Exchange (ETDEWEB)

    Dahn, Conard C.; Harris, Hugh C.; Subasavage, John P.; Ables, Harold D.; Guetter, Harry H.; Harris, Fred H.; Luginbuhl, Christian B.; Monet, Alice B.; Monet, David G.; Munn, Jeffrey A.; Pier, Jeffrey R.; Stone, Ronald C.; Vrba, Frederick J.; Walker, Richard L.; Tilleman, Trudy M. [US Naval Observatory, Flagstaff Station, 10391 W. Naval Observatory Road, Flagstaff, AZ 86005-8521 (United States); Canzian, Blaise J. [L-3 Communications/Brashear, 615 Epsilon Drive, Pittsburgh, PA 15238-2807 (United States); Henden, Arne H. [AAVSO, Cambridge, MA 02138 (United States); Leggett, S. K. [Gemini Observatory, Northern Operations Center, 670 N. A’ohoku Place, Hilo, HI 96720 (United States); Levine, Stephen E., E-mail: [Lowell Observatory, 1400 W. Mars Hill Road, Flagstaff, AZ 86001-4499 (United States)


    New, updated, and/or revised CCD parallaxes determined with the Strand Astrometric Reflector at the Naval Observatory Flagstaff Station are presented. Included are results for 309 late-type dwarf and subdwarf stars observed over the 30+ years that the program operated. For 124 of the stars, parallax determinations from other investigators have already appeared in the literature and we compare the different results. Also included here are new or updated VI photometry on the Johnson–Kron-Cousins system for all but a few of the faintest targets. Together with 2MASS JHK{sub s} near-infrared photometry, a sample of absolute magnitude versus color and color versus color diagrams are constructed. Because large proper motion was a prime criterion for targeting the stars, the majority turn out to be either M-type subdwarfs or late M-type dwarfs. The sample also includes 50 dwarf or subdwarf L-type stars, and four T dwarfs. Possible halo subdwarfs are identified in the sample based on tangential velocity, subluminosity, and spectral type. Residuals from the solutions for parallax and proper motion for several stars show evidence of astrometric perturbations.

  4. Semiautomated Precise Photometry (United States)

    Dunham, Edward W.


    Application of the transit photometry method for detecting extrasolar giant inner planets requires acquisition of a large amount of photometric data on each of several thousand stars over a period of many weeks. The observational workload is very high if these data are obtained manually, so we have made a semiautomated system to carry out the observations at Lowell's Mars Hill location. This is a compromise between the observational effort of a manual system and the complexity of a robotic system. The equipment currently in use consists of a Loral 2Kx2K charged coupled device (CCD) mounted at the focal plane of an Aero-Ektarf/2.5 aerial camera lens with 30.5-centimeter (cm) focal length. The CCD camera system is the modified SNAPSHOT camera system. It is set up to take a large number of exposures unattended during the night. The camera and dewar are mounted on a Celestron Computstar 14 telescope mount and autoguided with an SBIG ST4 autoguider attached to a Celestron C90 guide telescope. The current system needs to be set up manually each night and stowed each morning. In addition, if the weather deteriorates during the night, the equipment must be manually stowed for protection. A proposed upgrade to the current hardware will allow these functions to be handled remotely. This in turn will allow the system to operate efficiently at Lowell's darker but more remote Anderson Mesa site.

  5. Astronomical Photometry Past, Present, and Future

    CERN Document Server

    Milone, Eugene F


    This book brings together experts in the field of astronomical photometry to discuss how their subfields provide the precision and accuracy in astronomical energy flux measurements that are needed to permit tests of astrophysical theories. Differential photometers and photometry, improvements in infrared precision, the improvements in precision and accuracy of CCD photometry, the absolute calibration of flux, the development of the Johnson UBVRI photometric system and other passband systems to measure and precisely classify specific types of stars and astrophysical quantities, and the current capabilities of spectrophotometry and polarimetry to provide precise and accurate data, are all discussed in this volume. The discussion of `differential’ or `two-star’ photometers ranges from early experiments in visual photometry through the Harvard and Princeton polarizing photometers to the pioneering work of Walraven and differential photometers designed to minimize effects of atmospheric extinction and to count...

  6. The OCA CCD Camera Controller (United States)


    multi CCD arrays for wide field telescopes with an array of 8x8 1K CCDs in use at Las Campanas Observatory in Chile . The same group is also involved...Verify key EPROM -292H VIH . VIH Program security bitl 1 29AH . VPP Program security’ bit 2 *. .298H -Vpp Verify security bits - 9HVIH ViI NOTE: 1...Pulsed from V.. to VIL and returned to VIH . EPROM PROGRAMMING AND VERIFICATION ..t= 21’C to-+27 ’rC:-VCC= 5V ±10%VS3 = OV. SYMBOL I .-- PARAMETER MIN MAX

  7. Surface photometry of new nearby dwarf galaxies


    Makarova, L. N.; Karachentsev, I. D.; Grebel, E. K.; Barsunova, O. Yu.


    We present CCD surface photometry of 16 nearby dwarf galaxies, many of which were only recently discovered. Our sample comprises both isolated galaxies and galaxies that are members of nearby galaxy groups. The observations were obtained in the Johnson B and V bands (and in some cases in Kron-Cousins I). We derive surface brightness profiles, total magnitudes, and integrated colors. For the 11 galaxies in our sample with distance estimates the absolute B magnitudes lie in the range of -10>Mb>...

  8. VizieR Online Data Catalog: BVRI differential photometry of GW Gem (Lee+, 2009) (United States)

    Lee, J. W.; Kim, S.-L.; Lee, C.-U.; Kim, H.-I.; Park, J.-H.; Park, S.-R.; Koch, R. H.


    Our CCD photometry of GW Gem was performed on 13 nights during the period 2007 December 20-2008 March 1 in order to obtain multicolor light curves. The observations were taken with a SITe 2K CCD camera and a BVRI filter set attached to the 61-cm reflector at Sobaeksan Optical Astronomy Observatory (SOAO) in Korea. (1 data file).

  9. A Practical Guide to Lightcurve Photometry and Analysis

    CERN Document Server

    Warner, Brian D


    A Practical Guide to Lightcurve Photometry and Analysis provides, for those with access to even a modest telescope and CCD camera, all the information needed to take part in the scientific study of asteroids and variable stars. Using commercially available equipment, amateur astronomers can determine the rotation rate, size, and shape of asteroids. Similarly, it is possible to discover the size, temperature, and orbits of stars in binary systems by using this powerful technique. A Practical Guide to Lightcurve Photometry and Analysis contains all the material needed for readers to understand the theory, and avoid the practical pitfalls of lightcurve photometry. Detailed examples are given for obtaining data, and of course for the exciting and rewarding task of analyzing the data to determine the physical properties of the object. Any college student or amateur astronomer who wants to go beyond mere imaging with a CCD camera and enter the challenging world of "real science" via the lightcurves of asteroids and...

  10. Advanced CCD camera developments

    Energy Technology Data Exchange (ETDEWEB)

    Condor, A. [Lawrence Livermore National Lab., CA (United States)


    Two charge coupled device (CCD) camera systems are introduced and discussed, describing briefly the hardware involved, and the data obtained in their various applications. The Advanced Development Group Defense Sciences Engineering Division has been actively designing, manufacturing, fielding state-of-the-art CCD camera systems for over a decade. These systems were originally developed for the nuclear test program to record data from underground nuclear tests. Today, new and interesting application for these systems have surfaced and development is continuing in the area of advanced CCD camera systems, with the new CCD camera that will allow experimenters to replace film for x-ray imaging at the JANUS, USP, and NOVA laser facilities.

  11. Detection of interstellar CCD (United States)

    Combes, F.; Boulanger, F.; Encrenaz, P. J.; Gerin, M.; Bogey, M.


    The first detection of interstellar CCD has been obtained in the N = 3-2, J = 7/2-5/2 line at 216.3732 GHz towards the Kleinman-Low nebula. An abundance ratio CCD/CCH of 0.045 is found, indicating in this molecule a deuterium enhancement similar to that found for HNC, but an order of magnitude higher than for HCN. Negative results towards DR 21(OH), NGC 2264, L 134N, TM Cl, Rho OphB2, and IRC 10216 rule out a stronger D enhancement for CCD than for other deuterated molecules in these sources. Predictions of currently developed ion-molecule reaction schemes are consistent with the CCD line detected and the negative results.

  12. BRITE Constellation: data processing and photometry (United States)

    Popowicz, A.; Pigulski, A.; Bernacki, K.; Kuschnig, R.; Pablo, H.; Ramiaramanantsoa, T.; Zocłońska, E.; Baade, D.; Handler, G.; Moffat, A. F. J.; Wade, G. A.; Neiner, C.; Rucinski, S. M.; Weiss, W. W.; Koudelka, O.; Orleański, P.; Schwarzenberg-Czerny, A.; Zwintz, K.


    Context. The BRIght Target Explorer (BRITE) mission is a pioneering space project aimed at the long-term photometric monitoring of the brightest stars in the sky by means of a constellation of nanosatellites. Its main advantage is high photometric accuracy and time coverage which are inaccessible from the ground. Its main drawback is the lack of cooling of the CCD detectors and the absence of good shielding that would protect them from energetic particles. Aims: The main aim of this paper is the presentation of procedures used to obtain high-precision photometry from a series of images acquired by the BRITE satellites in two modes of observing, stare and chopping. The other aim is a comparison of the photometry obtained with two different pipelines and a comparison of the real scatter with expectations. Methods: We developed two pipelines corresponding to the two modes of observing. They are based on aperture photometry with a constant aperture, circular for stare mode of observing and thresholded for chopping mode. Impulsive noise is a serious problem for observations made in the stare mode of observing and therefore in the pipeline developed for observations made in this mode, hot pixels are replaced using the information from shifted images in a series obtained during a single orbit of a satellite. In the other pipeline, the hot pixel replacement is not required because the photometry is made in difference images. Results: The assessment of the performance of both pipelines is presented. It is based on two comparisons, which use data from six runs of the UniBRITE satellite: (I) comparison of photometry obtained by both pipelines on the same data, which were partly affected by charge transfer inefficiency (CTI), (II) comparison of real scatter with theoretical expectations. It is shown that for CTI-affected observations, the chopping pipeline provides much better photometry than the other pipeline. For other observations, the results are comparable only for data


    Energy Technology Data Exchange (ETDEWEB)

    Hartkopf, William I.; Mason, Brian D.; Finch, Charlie T.; Zacharias, Norbert; Wycoff, Gary L.; Hsu, Danley, E-mail:, E-mail:, E-mail:, E-mail: [US Naval Observatory, Washington, DC 20392 (United States)


    The newly completed Fourth USNO CCD Astrographic Catalog (UCAC4) has proven to be a rich source of double star astrometry and photometry. Following initial comparisons of UCAC4 results against those obtained by speckle interferometry, the UCAC4 catalog was matched against known double stars in the Washington Double Star Catalog in order to provide additional differential astrometry and photometry for these pairs. Matches to 58,131 pairs yielded 61,895 astrometric and 68,935 photometric measurements. Finally, a search for possible new common proper motion (CPM) pairs was made using new UCAC4 proper motion data; this resulted in 4755 new potential CPM doubles (and an additional 27,718 astrometric and photometric measures from UCAC and other sources)

  14. CCD Stability Monitor (United States)

    Grogin, Norman


    A moderately crowded stellar field in the cluster 47 Tuc {6 arcmin West of the cluster core} is observed every four months with the WFC. The first visit exercises the full suite of broad and narrow band imaging filters and sub-array modes; following visits observe with only the six most popular Cycle 18 filters in full-frame mode. The positions and magnitudes of objects will be used to monitor local and large scale variations in the plate scale and the sensitivity of the detectors and to derive an independent measure of the detector CTE. One exposure in each sub-array mode with the WFC will allow us to verify that photometry obtained in full-frame and in sub-array modes are repeatable to better than 1%. This test is important for the ACS Photometric Cross-Calibration program, which uses sub-array exposures.

  15. Transmission electron microscope CCD camera (United States)

    Downing, Kenneth H.


    In order to improve the performance of a CCD camera on a high voltage electron microscope, an electron decelerator is inserted between the microscope column and the CCD. This arrangement optimizes the interaction of the electron beam with the scintillator of the CCD camera while retaining optimization of the microscope optics and of the interaction of the beam with the specimen. Changing the electron beam energy between the specimen and camera allows both to be optimized.

  16. Aperture Photometry Tool (United States)

    Laher, Russ R.; Gorjian, Varoujan; Rebull, Luisa M.; Masci, Frank J.; Fowler, John W.; Helou, George; Kulkarni, Shrinivas R.; Law, Nicholas M.


    Aperture Photometry Tool (APT) is software for astronomers and students interested in manually exploring the photometric qualities of astronomical images. It is a graphical user interface (GUI) designed to allow the image data associated with aperture photometry calculations for point and extended sources to be visualized and, therefore, more effectively analyzed. The finely tuned layout of the GUI, along with judicious use of color-coding and alerting, is intended to give maximal user utility and convenience. Simply mouse-clicking on a source in the displayed image will instantly draw a circular or elliptical aperture and sky annulus around the source and will compute the source intensity and its uncertainty, along with several commonly used measures of the local sky background and its variability. The results are displayed and can be optionally saved to an aperture-photometry-table file and plotted on graphs in various ways using functions available in the software. APT is geared toward processing sources in a small number of images and is not suitable for bulk processing a large number of images, unlike other aperture photometry packages (e.g., SExtractor). However, APT does have a convenient source-list tool that enables calculations for a large number of detections in a given image. The source-list tool can be run either in automatic mode to generate an aperture photometry table quickly or in manual mode to permit inspection and adjustment of the calculation for each individual detection. APT displays a variety of useful graphs with just the push of a button, including image histogram, x and y aperture slices, source scatter plot, sky scatter plot, sky histogram, radial profile, curve of growth, and aperture-photometry-table scatter plots and histograms. APT has many functions for customizing the calculations, including outlier rejection, pixel “picking” and “zapping,” and a selection of source and sky models. The radial-profile-interpolation source

  17. VizieR Online Data Catalog: Photometry of supernova iPTF13z (Nyholm+, 2017) (United States)

    Nyholm, A.; Sollerman, J.; Taddia, F.; Fremling, C.; Moriya, T. J.; Ofek, E. O.; Gal-Yam, A.; De Cia, A.; Roy, R.; Kasliwal, M. M.; Cao, Y.; Nugent, P. E.; Masci, F. J.


    The 1.2m Samuel Oschin telescope (also called P48) was equipped with the CFH12K (12Kx8K pixel) CCD camera and a Mould R filter. The 1.52m telescope (also called P60) was equipped with a 2048x2048 pixel CCD camera and Sloan Digital Sky Survey (SDSS) gri and Johnson B filters. We present AB magnitudes from PSF photometry (relative photometry based on SDSS) on host subtracted images. The magnitudes are given along with their statistical errors (1 sigma). The photometry was done using the FPipe pipeline (2016A&A...593A..68F). The times of the measurements are given both as MJD and relative to time of SN discovery (JD 2456324.98). For the dates given in Table 3, measurements made within 1 day are considered to be simultaneous. The observations were made during 2013 Feb - 2016 Jan. (2 data files).

  18. ARCHANGEL: Galaxy Photometry System (United States)

    Schombert, James


    ARCHANGEL is a Unix-based package for the surface photometry of galaxies. While oriented for large angular size systems (i.e. many pixels), its tools can be applied to any imaging data of any size. The package core contains routines to perform the following critical galaxy photometry functions: sky determination; frame cleaning; ellipse fitting; profile fitting; and total and isophotal magnitudes. The goal of the package is to provide an automated, assembly-line type of reduction system for galaxy photometry of space-based or ground-based imaging data. The procedures outlined in the documentation are flux independent, thus, these routines can be used for non-optical data as well as typical imaging datasets. ARCHANGEL has been tested on several current OS's (RedHat Linux, Ubuntu Linux, Solaris, Mac OS X). A tarball for installation is available at the download page. The main routines are Python and FORTRAN based, therefore, a current installation of Python and a FORTRAN compiler are required. The ARCHANGEL package also contains Python hooks to the PGPLOT package, an XML processor and network tools which automatically link to data archives (i.e. NED, HST, 2MASS, etc) to download images in a non-interactive manner.

  19. ACS CCD Stability Monitor (United States)

    Grogin, Norman


    A moderately crowded stellar field in the cluster 47 Tuc {6 arcmin West of the cluster core} is observed every four months with the WFC. The first visit exercises the full suite of broad and narrow band imaging filters and sub-array modes; following visits observe with only the six most popular Cycle 18 filters in full-frame mode. The positions and magnitudes of objects will be used to monitor local and large scale variations in the plate scale and the sensitivity of the detectors and to derive an independent measure of the detector CTE. One exposure in each sub-array mode with the WFC will allow us to verify that photometry obtained in full-frame and in sub-array modes are repeatable to better than 1%. This test is important for the ACS Photometric Cross-Calibration program, which uses sub-array exposures. This program may receive additional orbits to investigate ORIENT-dependent geometric distortion, which motivates the ORIENT and BETWEEN requirement on the first visit.

  20. Testing fully depleted CCD (United States)

    Casas, Ricard; Cardiel-Sas, Laia; Castander, Francisco J.; Jiménez, Jorge; de Vicente, Juan


    The focal plane of the PAU camera is composed of eighteen 2K x 4K CCDs. These devices, plus four spares, were provided by the Japanese company Hamamatsu Photonics K.K. with type no. S10892-04(X). These detectors are 200 μm thick fully depleted and back illuminated with an n-type silicon base. They have been built with a specific coating to be sensitive in the range from 300 to 1,100 nm. Their square pixel size is 15 μm. The read-out system consists of a Monsoon controller (NOAO) and the panVIEW software package. The deafualt CCD read-out speed is 133 kpixel/s. This is the value used in the calibration process. Before installing these devices in the camera focal plane, they were characterized using the facilities of the ICE (CSIC- IEEC) and IFAE in the UAB Campus in Bellaterra (Barcelona, Catalonia, Spain). The basic tests performed for all CCDs were to obtain the photon transfer curve (PTC), the charge transfer efficiency (CTE) using X-rays and the EPER method, linearity, read-out noise, dark current, persistence, cosmetics and quantum efficiency. The X-rays images were also used for the analysis of the charge diffusion for different substrate voltages (VSUB). Regarding the cosmetics, and in addition to white and dark pixels, some patterns were also found. The first one, which appears in all devices, is the presence of half circles in the external edges. The origin of this pattern can be related to the assembly process. A second one appears in the dark images, and shows bright arcs connecting corners along the vertical axis of the CCD. This feature appears in all CCDs exactly in the same position so our guess is that the pattern is due to electrical fields. Finally, and just in two devices, there is a spot with wavelength dependence whose origin could be the result of a defectous coating process.

  1. CCD Camera Observations (United States)

    Buchheim, Bob; Argyle, R. W.

    One night late in 1918, astronomer William Milburn, observing the region of Cassiopeia from Reverend T.H.E.C. Espin's observatory in Tow Law (England), discovered a hitherto unrecorded double star (Wright 1993). He reported it to Rev. Espin, who measured the pair using his 24-in. reflector: the fainter star was 6.0 arcsec from the primary, at position angle 162.4 ^{circ } (i.e. the fainter star was south-by-southeast from the primary) (Espin 1919). Some time later, it was recognized that the astrograph of the Vatican Observatory had taken an image of the same star-field a dozen years earlier, in late 1906. At that earlier epoch, the fainter star had been separated from the brighter one by only 4.8 arcsec, at position angle 186.2 ^{circ } (i.e. almost due south). Were these stars a binary pair, or were they just two unrelated stars sailing past each other? Some additional measurements might have begun to answer this question. If the secondary star was following a curved path, that would be a clue of orbital motion; if it followed a straight-line path, that would be a clue that these are just two stars passing in the night. Unfortunately, nobody took the trouble to re-examine this pair for almost a century, until the 2MASS astrometric/photometric survey recorded it in late 1998. After almost another decade, this amateur astronomer took some CCD images of the field in 2007, and added another data point on the star's trajectory, as shown in Fig. 15.1.

  2. LEMON: an (almost) completely automated differential-photometry pipeline (United States)

    Terrón, V.; Fernández, M.


    We present LEMON, the CCD differential-photometry pipeline, written in Python, developed at the Institute of Astrophysics of Andalusia (CSIC) and originally designed for its use at the 1.23 m CAHA telescope for automated variable stars detection and analysis. The aim of our tool is to make it possible to completely reduce thousands of images of time series in a matter of hours and with minimal user interaction, if not none at all, automatically detecting variable stars and presenting the results to the astronomer.

  3. A practical guide to lightcurve photometry and analysis

    CERN Document Server

    Warner, Brian D


    For those with access to even a modest telescope and CCD camera, this new and improved guide delivers all the information needed to take part in the scientific study of asteroids and variable stars. New techniques in photometry continue to be refined, and expert Brian Warner covers the developing territory in detail for those both new and experienced. Updated to reflect changes in telescope and CCD technology, it also includes an expanded chapter on the analysis of asteroid lightcurves to cover some of the common pitfalls that lead to incorrect answers as well as how to discover an asteroid satellite via lightcurves. With this information, amateur astronomers can use commercially available equipment to determine the rotation rate, size, and shape of asteroids. Similarly, it is possible to discover the size, temperature, and orbits of stars in binary systems by using this powerful technique. Brian Warner yet again delivers all the material needed for readers to understand the theory, and avoid the practical pi...

  4. UBVRI photometry in NGC6791

    DEFF Research Database (Denmark)

    Brogaard, K.; Vandenberg, D. A.; Bruntt, H.


    New reduction of photometric B, V, I observations from Stetson et al. (2003, Cat. J/PASP/115/413) with updated photometry zero-points according to Stetson et al. (2005PASP..117..563S), and the same photometry, but empirically corrected for differential reddening using the procedure described...


    Directory of Open Access Journals (Sweden)

    Alexandru Dan Toma


    Full Text Available Typically, the total amount of gases and particles in a column of atmosphere cannot be determined from measurements just at Earth's surface, by a single measurement essentially at the bottom of the atmosphere column. Balloons, airplanes, and rockets are all used to perform direct measurements in the atmosphere at altitudes up to and beyond the stratosphere. Satellite-based instruments provide global views, but it is difficult to infer surface and column distributions from space-based measurements, so such measurements must still be supplemented by ground-based measurements. Sun photometry is an important way of probing the atmosphere from the ground to measure the effects of the atmosphere on Sun radiation crossing through the atmosphere to Earth's surface. These indirect technique provide information about the entire atmosphere above the observer, not just the atmosphere that can be sampled directly close to Earth's surface.

  6. Photometry of Phoebe (United States)

    Kruse, S.; Klavetter, J. J.; Dunham, E. W.


    The nonsynchronous rotational period and light curve for Phoebe are analyzed. The variations in CCD chip pixel response, the intensity of the images, the sky background level, and the atmospheric effects and color response of the detector are examined. Consideration is also given to brightness variations and the solar phase function at small phase angles (0.2-1.2 deg) of the light curve. The Phoebe surface is compared with asteroid surfaces by fitting the data to a linear phase function. It is determined that the Phoebe's sidereal rotational period is refined to 9.282 + or - 0.015 hr, the light curve in V filter exhibits 20 percent brightness variations with weaker higher-order harmonics, and the solar phase coefficient at angles less than 1.2 deg is 0.180 + or 0.035 mag/deg. The Phoebe data at small phase angles correlated well with a phase function for C-type asteroids.

  7. CCD camera for an autoguider (United States)

    Schempp, William V.


    The requirements of a charge coupled device (CCD) autoguider camera and the specifications of a camera that we propose to build to meet those requirements will be discussed. The design goals of both the package and the electronics will be considered.

  8. CCD Corner-Turning Memory. (United States)


    devices and exhibits the characteristic 1-(0 + t/r )l transient with T- CL/ gmo -18 ns, where gmo Is the device transconductence at t - 0+. Figure 63(b...Diamon, A. M. Mohsen, and T. C. McGill, "Charge Transfer In Buried Channel CCD’s," ISSCC Philadelphia, Digest of Tech. Papers, 146 (1974). 14. See

  9. Geometry VI

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 8. Geometry VI - Space-the Final Frontier. Kapil H Paranjape. Series Article Volume 1 Issue 8 August 1996 pp 28-33. Fulltext. Click here to view fulltext PDF. Permanent link: ...

  10. VI KA’

    DEFF Research Database (Denmark)

    Sprogøe, Jonas


    Artiklen handler om hvordan man kan bruge et spil til at udvikle og måle kompetencer. Artiklen diskuterer forskellige forståelser kompetencebegrebet og diskuterer hvordan Vi Ka'-spillet bidrager til at indfange den mere aktive forståelse af kompetence, som noget du gør i en bestemt kontekst....

  11. Is Flat fielding Safe for Precision CCD Astronomy? (United States)

    Baumer, Michael; Davis, Christopher P.; Roodman, Aaron


    The ambitious goals of precision cosmology with wide-field optical surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope (LSST) demand precision CCD astronomy as their foundation. This in turn requires an understanding of previously uncharacterized sources of systematic error in CCD sensors, many of which manifest themselves as static effective variations in pixel area. Such variation renders a critical assumption behind the traditional procedure of flat fielding—that a sensor’s pixels comprise a uniform grid—invalid. In this work, we present a method to infer a curl-free model of a sensor’s underlying pixel grid from flat-field images, incorporating the superposition of all electrostatic sensor effects—both known and unknown—present in flat-field data. We use these pixel grid models to estimate the overall impact of sensor systematics on photometry, astrometry, and PSF shape measurements in a representative sensor from the Dark Energy Camera (DECam) and a prototype LSST sensor. Applying the method to DECam data recovers known significant sensor effects for which corrections are currently being developed within DES. For an LSST prototype CCD with pixel-response non-uniformity (PRNU) of 0.4%, we find the impact of “improper” flat fielding on these observables is negligible in nominal .7″ seeing conditions. These errors scale linearly with the PRNU, so for future LSST production sensors, which may have larger PRNU, our method provides a way to assess whether pixel-level calibration beyond flat fielding will be required.

  12. Signal-to-noise considerations for sky-subtracted CCD data (United States)

    Newberry, Michael V.


    The standard equation for calculating the uncertainty of photometry obtained from CCDs does not correctly consider the random errors, or 'noise', introduced into observations by procedures used in reducing the data. This paper presents a thorough derivation of the theoretical error equation that considers the contributions from all internal noise sources in the signal-to-noise ratio (S/N) of a sky-subtracted image. A simplified version used for estimating the internal errors from empirical data is also derived. The propagation of noise through the data-reduction process is illustrated through a series of equations for the change in S/N that results from a variety of different operations performed on a CCD frame. Comparing these effects with the results expected for an observation made with an ideal detector suggests a number of ways to improve the precision of photometry through the practices employed in obtaining and reducing the observations.

  13. CCD research. [design, fabrication, and applications (United States)

    Gassaway, J. D.


    The fundamental problems encountered in designing, fabricating, and applying CCD's are reviewed. Investigations are described and results and conclusions are given for the following: (1) the development of design analyses employing computer aided techniques and their application to the design of a grapped structure; (2) the role of CCD's in applications to electronic functions, in particular, signal processing; (3) extending the CCD to silicon films on sapphire (SOS); and (4) all aluminum transfer structure with low noise input-output circuits. Related work on CCD imaging devices is summarized.

  14. Photometry of Karin family asteroids

    NARCIS (Netherlands)

    Hahn, G.; Mottola, S.; Sen, A. K.; Harris, A. W.; Kührt, E.; Mueller, M.


    We have performed photometric observations in the V-band of two asteroids belonging to the Karin asteroid family, (11728) Einer and (93690) 2000 VE21 , using the 2-m Himalayan Chandra Telescope, Hanle and 2k ×4k pixels CCD imager. We obtained measurements during two nights (November 25 and 26, 2005)

  15. Mucopolysaccharidosis VI (United States)


    Mucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine), severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally sialidosis and mucolipidosis. Before enzyme replacement therapy (ERT) with galsulfase (Naglazyme®), clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided. PMID:20385007

  16. Mucopolysaccharidosis VI

    Directory of Open Access Journals (Sweden)

    Harmatz Paul


    Full Text Available Abstract Mucopolysaccharidosis VI (MPS VI is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine, severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally ARSB gene, located in chromosome 5 (5q13-5q14. Over 130 ARSB mutations have been reported, causing absent or reduced arylsulfatase B (N-acetylgalactosamine 4-sulfatase activity and interrupted dermatan sulfate and chondroitin sulfate degradation. Diagnosis generally requires evidence of clinical phenotype, arylsulfatase B enzyme activity ®, clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided.

  17. CCD-based vertex detectors

    CERN Document Server

    Damerell, C J S


    Over the past 20 years, CCD-based vertex detectors have been used to construct some of the most precise 'tracking microscopes' in particle physics. They were initially used by the ACCMOR collaboration for fixed target experiments in CERN, where they enabled the lifetimes of some of the shortest-lived charm particles to be measured precisely. The migration to collider experiments was accomplished in the SLD experiment, where the original 120 Mpixel detector was later upgraded to one with 307 Mpixels. This detector was used in a range of physics studies which exceeded the capability of the LEP detectors, including the most precise limit to date on the Bs mixing parameter. This success, and the high background hit densities that will inevitably be encountered at the future TeV-scale linear collider, have established the need for a silicon pixel-based vertex detector at this machine. The technical options have now been broadened to include a wide range of possible silicon imaging technologies as well as CCDs (mon...

  18. Cryostat and CCD for MEGARA at GTC (United States)

    Castillo-Domínguez, E.; Ferrusca, D.; Tulloch, S.; Velázquez, M.; Carrasco, E.; Gallego, J.; Gil de Paz, A.; Sánchez, F. M.; Vílchez Medina, J. M.


    MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is the new integral field unit (IFU) and multi-object spectrograph (MOS) instrument for the GTC. The spectrograph subsystems include the pseudo-slit, the shutter, the collimator with a focusing mechanism, pupil elements on a volume phase holographic grating (VPH) wheel and the camera joined to the cryostat through the last lens, with a CCD detector inside. In this paper we describe the full preliminary design of the cryostat which will harbor the CCD detector for the spectrograph. The selected cryogenic device is an LN2 open-cycle cryostat which has been designed by the "Astronomical Instrumentation Lab for Millimeter Wavelengths" at INAOE. A complete description of the cryostat main body and CCD head is presented as well as all the vacuum and temperature sub-systems to operate it. The CCD is surrounded by a radiation shield to improve its performance and is placed in a custom made mechanical mounting which will allow physical adjustments for alignment with the spectrograph camera. The 4k x 4k pixel CCD231 is our selection for the cryogenically cooled detector of MEGARA. The characteristics of this CCD, the internal cryostat cabling and CCD controller hardware are discussed. Finally, static structural finite element modeling and thermal analysis results are shown to validate the cryostat model.

  19. Kepler photometry of KIC10661783

    DEFF Research Database (Denmark)

    Southworth, J.; Pavlovski, K.; Smalley, B.


    We present Kepler satellite photometry of KIC 10661783, a short-period binary star system which shows total eclipses and multiperiodic δ Scuti pulsations. A frequency analysis of the eclipse-subtracted light curve reveals at least 68 frequencies, of which 55 or more can be attributed to pulsation...... of the two stars to be measured to high precision and hundreds of δ Scuti pulsation frequencies to be resolved. This could lead to unique constraints on theoretical models of δ Scuti stars, if the evolutionary history of KIC 10661783 can be accounted for....

  20. Development of CCD controller for scientific application (United States)

    Khan, M. S.; Pathan, F. M.; Shah, U. V., Prof; Makwana, D. H., Prof; Anandarao, B. G., Prof


    Photoelectric equipment has wide applications such as spectroscopy, temperature measurement in infrared region and in astronomical research etc. A photoelectric transducer converts radiant energy into electrical energy. There are two types of photoelectric transducers namely photo-multiplier tube (PMT) and charged couple device (CCD) are used to convert radiant energy into electrical signal. Now the entire modern instruments use CCD technology. We have designed and developed a CCD camera controller using camera chip CD47-10 of Marconi which has 1K × 1K pixel for space application only.

  1. CCD OBSERVATIONS V1.0 (United States)

    National Aeronautics and Space Administration — Charged Coupled Device (CCD) cameras from ESO were used by groups to observe the outburst of comet Halley using a variety of telescopes and chip sets.

  2. Silvaco ATLAS model of ESA's Gaia satellite e2v CCD91-72 pixels (United States)

    Seabroke, George; Holland, Andrew; Burt, David; Robbins, Mark


    The Gaia satellite is a high-precision astrometry, photometry and spectroscopic ESA cornerstone mission, currently scheduled for launch in 2012. Its primary science drivers are the composition, formation and evolution of the Galaxy. Gaia will achieve its unprecedented accuracy requirements with detailed calibration and correction for CCD radiation damage and CCD geometric distortion. In this paper, the third of the series, we present our 3D Silvaco ATLAS model of the Gaia e2v CCD91-72 pixel. We publish e2v's design model predictions for the capacities of one of Gaia's pixel features, the supplementary buried channel (SBC), for the first time. Kohley et al. (2009) measured the SBC capacities of a Gaia CCD to be an order of magnitude smaller than e2v's design. We have found the SBC doping widths that yield these measured SBC capacities. The widths are systematically 2 μm offset to the nominal widths. These offsets appear to be uncalibrated systematic offsets in e2v photolithography, which could either be due to systematic stitch alignment offsets or lateral ABD shield doping diffusion. The range of SBC capacities were used to derive the worst-case random stitch error between two pixel features within a stitch block to be +/-0.25 μm, which cannot explain the systematic offsets. It is beyond the scope of our pixel model to provide the manufacturing reason for the range of SBC capacities, so it does not allow us to predict how representative the tested CCD is. This open question has implications for Gaia's radiation damage and geometric calibration models.

  3. Modelling electron distributions within ESA's Gaia satellite CCD pixels to mitigate radiation damage (United States)

    Seabroke, G. M.; Holland, A. D.; Burt, D.; Robbins, M. S.


    The Gaia satellite is a high-precision astrometry, photometry and spectroscopic ESA cornerstone mission, currently scheduled for launch in 2012. Its primary science drivers are the composition, formation and evolution of the Galaxy. Gaia will achieve its unprecedented positional accuracy requirements with detailed calibration and correction for radiation damage. At L2, protons cause displacement damage in the silicon of CCDs. The resulting traps capture and emit electrons from passing charge packets in the CCD pixel, distorting the image PSF and biasing its centroid. Microscopic models of Gaia's CCDs are being developed to simulate this effect. The key to calculating the probability of an electron being captured by a trap is the 3D electron density within each CCD pixel. However, this has not been physically modelled for the Gaia CCD pixels. In Seabroke, Holland & Cropper (2008), the first paper of this series, we motivated the need for such specialised 3D device modelling and outlined how its future results will fit into Gaia's overall radiation calibration strategy. In this paper, the second of the series, we present our first results using Silvaco's physics-based, engineering software: the ATLAS device simulation framework. Inputting a doping profile, pixel geometry and materials into ATLAS and comparing the results to other simulations reveals that ATLAS has a free parameter, fixed oxide charge, that needs to be calibrated. ATLAS is successfully benchmarked against other simulations and measurements of a test device, identifying how to use it to model Gaia pixels and highlighting the affect of different doping approximations.

  4. Four Decades of TiO/CN Classification Photometry (United States)

    Wing, Robert F.


    Photometry on the writer's eight-color narrow-band system has entered its 40th year. This poster, in connection with the HAD Special Session on "Photometry: Past and Present," reviews the history of the system and its applications. Employing interference filters approximately 50 Å in width to measure the strongest bands of TiO, VO, and CN as well as continuum points in the 7000 -- 11000 Å spectral region, the system is used primarily to provide two-dimensional spectral classifications for M stars. A precision of 0.1 spectral subtype is routinely obtained for normal stars of type K4.0 or later. The first two sets of filters were manufactured in 1969, and the first observations were made with the Perkins 1.8-m telescope at Lowell Observatory. A decade later, after some of the original filters had deteriorated, new filter sets were made for several individuals and observatories including KPNO and CTIO. During the 1970s, observations were made with S-1 photomultipliers and the emphasis was on bright stars. Later, with the acquisition of the more sensitive Varian LSE photocells by both KPNO and CTIO, observations extended to red giant cluster members, K and M supergiants in the Magellanic Clouds, and faint suspected Galactic supergiants. Observations were briefly interrupted when the ASCAP photometer at CTIO was taken out of service in 2001, but were resumed in 2003 with the establishment of the SMARTS consortium. Large-format filters representing the first 6 filters of the 8-color system have been acquired to allow work by CCD imaging. At least 15 observers have contributed an estimated 16,000 sets of narrow-band data for approximately 5000 different stars to date.

  5. The calibration of read-out-streak photometry in the XMM-Newton Optical Monitor and the construction of a bright-source catalogue (United States)

    Page, M. J.; Chan, N.; Breeveld, A. A.; Talavera, A.; Yershov, V.; Kennedy, T.; Kuin, N. P. M.; Hancock, B.; Smith, P. J.; Carter, M.


    The dynamic range of the XMM-Newton Optical Monitor (XMM-OM) is limited at the bright end by coincidence loss, the superposition of multiple photons in the individual frames recorded from its micro-channel-plate (MCP) intensified charge-coupled device (CCD) detector. One way to overcome this limitation is to use photons that arrive during the frame transfer of the CCD, forming vertical read-out streaks for bright sources. We calibrate these read-out streaks for photometry of bright sources observed with XMM-OM. The bright-source limit for read-out-streak photometry is set by the recharge time of the MCPs. For XMM-OM, we find that the MCP recharge time is 5.5 × 10-4 s. We determine that the effective bright limits for read-out-streak photometry with XMM-OM are approximately 1.5 mag brighter than the bright-source limits for normal aperture photometry in full-frame images. This translates into bright-source limits in Vega magnitudes of UVW2=7.1, UVM2=8.0, UVW1=9.4, U=10.5, B=11.5, V=10.2, and White=12.5 for data taken early in the mission. The limits brighten by up to 0.2 mag, depending on filter, over the course of the mission as the detector ages. The method is demonstrated by deriving UVW1 photometry for the symbiotic nova RR Telescopii, and the new photometry is used to constrain the e-folding time of its decaying ultraviolet (UV) emission. Using the read-out-streak method, we obtain photometry for 50 per cent of the missing UV source measurements in version 2.1 of the XMM-Newton Serendipitous UV Source Survey catalogue.

  6. Cranial mononeuropathy VI (United States)

    ... Abducens palsy; Lateral rectus palsy; VIth nerve palsy; Cranial nerve VI palsy; Sixth nerve palsy; Neuropathy - sixth nerve ... Cranial mononeuropathy VI is damage to the sixth cranial nerve. This nerve is also called the abducens nerve. ...

  7. Active Pixel Sensors: Are CCD's Dinosaurs? (United States)

    Fossum, Eric R.


    Charge-coupled devices (CCD's) are presently the technology of choice for most imaging applications. In the 23 years since their invention in 1970, they have evolved to a sophisticated level of performance. However, as with all technologies, we can be certain that they will be supplanted someday. In this paper, the Active Pixel Sensor (APS) technology is explored as a possible successor to the CCD. An active pixel is defined as a detector array technology that has at least one active transistor within the pixel unit cell. The APS eliminates the need for nearly perfect charge transfer -- the Achilles' heel of CCDs. This perfect charge transfer makes CCD's radiation 'soft,' difficult to use under low light conditions, difficult to manufacture in large array sizes, difficult to integrate with on-chip electronics, difficult to use at low temperatures, difficult to use at high frame rates, and difficult to manufacture in non-silicon materials that extend wavelength response.

  8. Irregular Variability In Kepler Photometry (United States)

    Schlecker, Martin


    The transit method is the most successful tool for exoplanet discovery to date. With more than half of all known exoplanets discovered by Kepler using this method, the mission also revealed a number of objects with dimming events that defy the common explanations, the most prominent being KIC 8462852 aka ``Tabby's star''. I embarked on a search for objects with such irregular transit signatures in the data of K2, the two-wheeled successor mission of Kepler. My method is a combination of automated pre-selection of targets showing downward flux excursions and visual light curve inspection of the selected subset comprising about SI{1.5}% of the initial sample. In addition, I developed a tool to constrain the effective temperature of a planet-hosting star from photometry alone. This software finds broad application in any science case where a photometric spectral type estimate is necessary. I used existing transit models and Bayesian inference to perform a Markov Chain Monte Carlo (MCMC) analysis of a planetary candidate I discovered. This putative gas giant is in a SI{1.32}day circular orbit with an exceptionally tight orbital radius of a ≈ 0.012 AU. My analysis revealed a scaled planetary radius of R_{p}/R_star = 0.0927±0.0026 and an edge-on orientation with an inclination i=89.8+3.0-3.4. EPIC 217393088.01 is one of the closest-orbiting exoplanets ever detected and the first giant planet with such a small orbital radius. An additional major finding of my search is EPIC 220262993, which exhibits aperiodic, asymmetric dips in flux with rapid dimming rates and up to SI{˜25}% depth, lasting for SIrange{2}{4} day. In previous works based on optical and mid-infrared photometry, this object was inconsistently classified as a possible quasar or a white dwarf. We conducted follow-up observations both photometrically with GROND on the MPI/ESO SI{2.2} meter telescope in La Silla (Chile) and spectroscopically with FIRE on the Magellan/Baade SI{6.5} meter telescope. With

  9. First photometry results from Gaia (United States)

    Brown, Anthony


    An overview of the Gaia Photometric Processing is presented. The Gaia photometry consists of the white light (330-1050 nm) G-band, and low resolution spectrophotometry realized by two prisms dispersing all the light entering the field of view. One disperser - called BP for Blue Photometer- operates in the wavelength range 330-680 nm; the other - called RP for Red Photometer - covers the wavelength range 640-1050 nm. The light collected by BP and RP can also be integrated into two broad bands, G_BP and G_RP.This photometric data reduction is based on the overall principle of a self-calibrating system improved by iteration. The input data includes flux (G, G_BP, G_RP) and the low-resolution spectral data. The calibration models and algorithms used are described. Initial validation results are shown which indicate the photometric quality of the preliminary calibrated data. Expectations for the quality of the photometric data to be included in the first public data release (mid-2016) are discussed.

  10. Calibration of BVRI Photometry for the Wide Field Channel of the HST Advanced Camera for Surveys (United States)

    Saha, Abhijit; Shaw, Richard A.; Claver, Jennifer A.; Dolphin, Andrew E.


    We present new observations of two Galactic globular clusters, PAL4 and PAL14, using the Wide Field Channel of the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST) and reanalyze archival data from a third, NGC2419. We matched our photometry of hundreds of stars in these fields from the ACS images to existing ground-based photometry of faint sequences that were calibrated on the standard BVRI system of Landolt. These stars are significantly fainter than those generally used for HST calibration purposes and therefore are much better matched to supporting precision photometry of ACS science targets. We were able to derive more accurate photometric transformation coefficients for the commonly used ACS broadband filters, compared with those published by Sirianni et al., due to the use of a factor of several more calibration stars that span a greater range of color. We find that the inferred transformations from each cluster individually do not vary significantly from the average, except for a small offset of the photometric zero point in the F850LP filter. Our results suggest that the published prescriptions for the time-dependent correction of CCD charge transfer efficiency appear to work very well over the ˜3.5 yr interval that spans our observations of PAL4 and PAL14 and the archived images of NGC2419.

  11. The initial mass function for massive stars in the Magellanic Clouds. 1: UBV photometry and color-magnitude diagrams for 14 OB associations (United States)

    Hill, Robert J.; Madore, Barry F.; Freedman, Wendy L.


    UBV charge coupled device (CCD) photometry has been obtained for 14 OB associations in the Magellanic Clouds using the University of Toronto's 0.6 m telescope and the Carnegie Institution of Washington's 1.0 m reflector, both on Las Campanas, Chile. The data are presented and used to construct color-magnitude diagrams for the purposes of investigating the massive-star content of the associations.

  12. photPARTY: Python automated square-aperture photometry (United States)

    Symons, Teresa A.; Anthony-Twarog, Barbara J.


    As CCD’s have drastically increased the amount of information recorded per frame, so too have they increased the time and effort needed to sift through the data. For observations of a single star, information from millions of pixels needs to be distilled into one number: the magnitude. Various computer systems have been used to streamline this process over the years. The CCDPhot photometer, in use at the Kitt Peak 0.9-m telescope in the 1990’s, allowed for user settings and provided real time magnitudes during observation of single stars. It is this level of speed and convenience that inspired the development of the Python-based software analysis system photPARTY, which can quickly and efficiently produce magnitudes for a set of single-star or un-crowded field CCD frames. Seeking to remove the need for manual interaction after initial settings for a group of images, photPARTY automatically locates stars, subtracts the background, and performs square-aperture photometry. Rather than being a package of available functions, it is essentially a self-contained, one-click analysis system, with the capability to process several hundred frames in just a couple of minutes. Results of comparisons against present systems such as IRAF will be presented. The support of the National Science Foundation through grant AST-1211621 is gratefully acknowledged.

  13. Protein diffraction experiments with Atlas CCD detector

    Czech Academy of Sciences Publication Activity Database

    Dohnálek, Jan; Kovaľ, Tomáš; Dušek, Michal


    Roč. 64, Suppl. - abstracts (2008), C192 ISSN 0108-7673. [Congress of the International Union of Crystallography (IUCr) /21./. 23.08.2008-31.08.2008, Osaka] Institutional research plan: CEZ:AV0Z10100521 Keywords : x-ray data collection * CCD detectors * protein crystallography applications Subject RIV: BM - Solid Matter Physics ; Magnetism

  14. A Survey of Star Clusters in the M31 South-West Field. UBVRI Photometry and Multi-Band Maps


    Narbutis, D.; Vansevicius, V.; Kodaira, K.; Bridzius, A.; Stonkute, R.


    A new survey of star clusters in the South-West field of the M31 disk based on the high resolution Subaru Suprime-Cam observations is presented. The UBVRI aperture CCD photometry catalog of 285 objects (V < 20.5; 169 of them identified for the first time) is provided. Each object is supplemented with multi-band color maps presented in the electronic edition of the Astrophysical Journal Supplement. Seventy seven star cluster candidates from the catalog are located in the Hubble Space Telescope...

  15. Design of a multifunction astronomical CCD camera (United States)

    Yao, Dalei; Wen, Desheng; Xue, Jianru; Chen, Zhi; Wen, Yan; Jiang, Baotan; Xi, Jiangbo


    To satisfy the requirement of the astronomical observation, a novel timing sequence of frame transfer CCD is proposed. The multiple functions such as the adjustments of work pattern, exposure time and frame frequency are achieved. There are four work patterns: normal, standby, zero exposure and test. The adjustment of exposure time can set multiple exposure time according to the astronomical observation. The fame frequency can be adjusted when dark target is imaged and the maximum exposure time cannot satisfy the requirement. On the design of the video processing, offset correction and adjustment of multiple gains are proposed. Offset correction is used for eliminating the fixed pattern noise of CCD. Three gains pattern can improve the signal to noise ratio of astronomical observation. Finally, the images in different situations are collected and the system readout noise is calculated. The calculation results show that the designs in this paper are practicable.

  16. A self triggered intensified CCD (STIC) (United States)

    Charon, Y.; Laniece, P.; Bendali, M.; Gaillard, J. M.; Leblanc, M.; Mastrippolito, R.; Tricoire, H.; Valentin, L.


    We are developing a new device based on the results reported previously of the successful coincidence detection of β - particles with a high spatial resolution. The novelty of the device consists in triggering and intensified CCD, i.e. a CCD coupled to an image intensifier (II), by an electrical signal collected from the II itself. This is a suitable procedure for detecting low light and rare events with high efficiency and high resolution. The trigger pulse is obtained from the secondary electrons produced by multiplication in a double microchannel plate (MCP) and collected on the aluminized layer protecting the phosphor screen in the II. Triggering efficiencies up to 80% have already been achieved.

  17. Photometry of Damocloid Asteroid 2006 BZ8 (United States)

    Hergenrother, Carl W.


    Photometry of the Damocloid asteroid 2006 BZ8 was obtained on two nights in 2006 February with the University of Arizona Kuiper 1.54-m telescope. Lightcurve analysis yielded a rotation period of 5.960 ± 0.003 h and amplitude of 0.35 magnitudes. An analysis of photometry reported by the Catalina Sky Survey, Mount Lemmon Survey. and Siding Spring Survey to the Minor Planet Center found a steep phase function slope of b_V = 0.054 ± 0.008 which is consistent with 2006 BZ8 being a very low albedo object.

  18. Jonckheere Double Star Photometry - Part VII: Aquarius (United States)

    Knapp, Wilfried R. A.


    If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part of them with magnitudes obviously far too bright. This report covers the Jonckheere objects in the constellation Aquarius. One image per object was taken with V-filter to allow for visual magnitude measurement by differential pho-tometry. All objects were additionally checked for common proper motion by comparing 2MASS to GAIA DR1 positions and a rather surprisingly large part of the objects qualify indeed as potential CPM pairs. For a few objects also WDS position errors were found.

  19. VizieR Online Data Catalog: Optical & Spitzer photometry in IC 1805 (Sung+, 2017) (United States)

    Sung, H.; Bessell, M. S.; Chun, M.-Y.; Yi, J.; Naze, Y.; Lim, B.; Karimov, R.; Rauw, G.; Park, B.-G.; Hur, H.


    For a study of the IMF and the star-formation history of the young open cluster IC 1805, we obtained deep wide-field VRI and Hα images of IC 1805 using the CFH12K mosaic CCD camera of the CFHT on 2002 January 6 and 7. We also observed several regions in IC 1805, for a study of the reddening and massive star content, using the SITe 2000x800 CCD (Maidanak 2k CCD) and standard UBVRI filters of the AZT-22 1.5m telescope at the Maidanak Astronomical Observatory in Uzbekistan on 2003 August 18 and 2004 december 25,30. Later, we obtained additional images of the central region of IC 1805 with the Fairchild 486 CCD (SNUCam) and UBVI and Hα filters of the AZT-22 telescope on 2007 October 7 and 2009 January 19. The Spitzer mapping observations were performed on 2006 September 20 under program ID 20052 (PI: S. Wolff). For complete photometry of stars in the CFH12K FOV in 3.6 and 4.5um, we also downloaded and reduced the GLIMPSE360 data (AOR: 38753280, 38763264, 38769408, 38799104, 38798592, 38784512, PI: B. A. Whitney). MIPS scans of IC 1805 were obtained on 2005 August 31 and 2005 September 2 (PID 3234, PI: J. S. Greeves). The Chandra X-ray Observatory Observations of IC 1805 (ObsID: 7033, PI: L. Townley) were made on 2006 November 25. The total exposure time was about 79ks. The properties of 647 X-ray sources were published in Townsley+ (2014,J/ApJS/213/1). We searched for the optical and MIR counterparts of these X-ray sources with a matching radius of up to 1.5". (4 data files).

  20. Photometry of the Occator faculae on Ceres (United States)

    Longobardo, A.; Palomba, E.; De Sanctis, M. C.; Ciarniello, M.; Galliano, A.; Tosi, F.; Carrozzo, F. G.; Raponi, A.; Capria, M. T.; Zambon, F.; Ammannito, E.; Rognini, E.; Raymond, C. A.; Russell, C. T.


    We study the photometric behavior of reflectance and band depths on the Occator faculae on Ceres and compare it with the Ceres average. The different photometry between Occator and the rest of Ceres indicates that Occator is peculiar not only for the composition, but also for physical properties.


    NARCIS (Netherlands)



    Low surface brightness (LSB) galaxies are galaxies dominated by an exponential disc whose central surface brightness is much fainter than the value of mu(B)(0) = 21.65 +/- 0.30 mag arcsec(-2) found by Freeman. In this paper we present broadband photometry of a sample of 21 late-type LSB galaxies.

  2. NIR photometry of M31LRN 2015 (United States)

    Geier, Stefan; Pessev, Peter


    A new epoch JHKs NIR photometry of the stellar merger candidate MASTER OT J004207.99+405501.1 / M31N 2015-01a / M31LRN 2015 (Kurtenkov et al. 2015, Williams et al. 2015, ATel #6911, ATel #7150) has been obtained.

  3. A Remotely Operated Observatory for Minor Planet Photometry (United States)

    Ditteon, Richard


    In October of 2007 Rose-Hulman Institute of Technology in Terre Haute, Indiana began operating the Oakley Southern Sky Observatory (E09) located near Siding Spring Observatory in New South Wales, Australia. The observatory houses a 0.5-m, f/8.4 Ritchey-Chretien telescope mounted on a Paramount ME, German equatorial mount. Attached to the telescope is an STL-1001E CCD camera which has 1024 by 1024, 24 µm pixels, a two-stage thermoelectric cooler, and built in color filter wheel with BVRI and clear filters. Image scale is 1.2 arcseconds per pixel. A cloud sensor is used to monitor sky conditions. The observatory has a roll-off roof with limit switches to detect when the roof is fully open and fully closed. In addition, a switch has been added to the mount to detect when the telescope is parked and that it is safe to open or close the roof. All of the hardware is controlled by a custom program which reads a simple text file containing the sequence of images and targets to be collected each night. The text file is loaded onto the control computer once each day, then the software waits until sunset to determine if the sky is clear. When conditions are favorable, power is turned on, the roof opens, twilight flats, dark and bias frames are recorded, and when it is fully dark data frames are recorded. Images are transferred via the Internet back to Rose-Hulman by another program running in the background. The observatory closes itself before dawn or if it gets cloudy. Currently we are using the observatory for photometry of minor planets. Students are responsible for selecting targets, processing the returned images, determining the period and light curve of each minor planet and writing a paper for publication. Recent results will be presented.

  4. Enumerating Photography from Spot Meter to CCD


    Cubitt, Sean; Palmer, Daniel; Walkling, Les


    The transition from analogue to digital photography was not accomplished in a single step. It required a number of feeder technologies which enabled and structured the nature of digital photography. Among those traced in this article, the most important is the genesis of the raster grid, which is now hard-wired into the design of the most widely employed photographic chip, the charge-coupled device (CCD). In tracing this history from origins in half-tone printing, the authors argue that quali...

  5. The Dark Energy Survey CCD imager design

    Energy Technology Data Exchange (ETDEWEB)

    Cease, H.; DePoy, D.; Diehl, H.T.; Estrada, J.; Flaugher, B.; Guarino, V.; Kuk, K.; Kuhlmann, S.; Schultz, K.; Schmitt, R.L.; Stefanik, A.; /Fermilab /Ohio State U. /Argonne


    The Dark Energy Survey is planning to use a 3 sq. deg. camera that houses a {approx} 0.5m diameter focal plane of 62 2kx4k CCDs. The camera vessel including the optical window cell, focal plate, focal plate mounts, cooling system and thermal controls is described. As part of the development of the mechanical and cooling design, a full scale prototype camera vessel has been constructed and is now being used for multi-CCD readout tests. Results from this prototype camera are described.

  6. Vi, de civiliserede

    DEFF Research Database (Denmark)

    Nyemann, Dorthe


    Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?......Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?...

  7. CCD developed for scientific application by Hamamatsu

    CERN Document Server

    Miyaguchi, K; Dezaki, J; Yamamoto, K


    We have developed CCDs for scientific applications that feature a low readout noise of less than 5 e-rms and low dark current of 10-25 pA/cm sup 2 at room temperature. CCDs with these characteristics will prove extremely useful in applications such as spectroscopic measurement and dental radiography. In addition, a large-area CCD of 2kx4k pixels and 15 mu m square pixel size has recently been completed for optical use in astronomical observations. Applications to X-ray astronomy require the most challenging device performance in terms of deep depletion, high CTE, and focal plane size, among others. An abuttable X-ray CCD, having 1024x1024 pixels and 24 mu m square pixel size, is to be installed in an international space station (ISS). We are now striving to achieve the lowest usable cooling temperature by means of a built-in TEC with limited power consumption. Details on the development status are described in this report. We would also like to present our future plans for a large active area and deep depleti...

  8. CCD Camera Detection of HIV Infection. (United States)

    Day, John R


    Rapid and precise quantification of the infectivity of HIV is important for molecular virologic studies, as well as for measuring the activities of antiviral drugs and neutralizing antibodies. An indicator cell line, a CCD camera, and image-analysis software are used to quantify HIV infectivity. The cells of the P4R5 line, which express the receptors for HIV infection as well as β-galactosidase under the control of the HIV-1 long terminal repeat, are infected with HIV and then incubated 2 days later with X-gal to stain the infected cells blue. Digital images of monolayers of the infected cells are captured using a high resolution CCD video camera and a macro video zoom lens. A software program is developed to process the images and to count the blue-stained foci of infection. The described method allows for the rapid quantification of the infected cells over a wide range of viral inocula with reproducibility, accuracy and at relatively low cost.

  9. New Design Concept for Universal CCD Controller

    Directory of Open Access Journals (Sweden)

    Wonyong Han


    Full Text Available Currently, the CCDs are widely used in astronomical observations either in direct imaging use or spectroscopic mode. However according to the recent technical advances, new large format CCDs are rapidly developed which have better performances with higher quantum efficiency and sensitivity. In many cases, some microprocessors have been adopted to deal with necessary digital logic for a CCD imaging system. This could often lack the flexibility of a system for a user to upgrade with new devices, especially of it is a commercial product. A new design concept has been explored which could provide the opportunity to deal with any format of devices from ant manufactures effectively for astronomical purposes. Recently available PLD (Programmable Logic Devices technology makes it possible to develop such digital circuit design, which can be integrated into a single component, instead of using microprocessors. The design concept could dramatically increase the efficiency and flexibility of a CCD imaging system, particularly when new or large format devices are available and to upgrade the performance of a system. Some variable system control parameters can be selected by a user with a wider range of choice. The software can support such functional requirements very conveniently. This approach can be applied not only to astronomical purpose, but also to some related fields, such as remote sensing and industrial applications.

  10. The AAVSO Photoelectric Photometry Program in its Scientific and Socio-Historic Context (United States)

    Percy, John R.


    Photoelectric photometry began in the 1900s through the work of Guthnick, Stebbins, and others who constructed and used photometers based on the recently-discovered photoelectric effect. The mid 20th century saw a confluence of several areas of amateur interest: astronomy, telescope making, radio and electronics, and general interest in space. This is the time when AAVSO photoelectric photometry (PEP) began, with observers using mostly hand-built photometers on hand-built telescopes. The 1980s brought a revolution: affordable off-the-shelf solid-state photometers, and infrastructure such as the International Amateur-Professional Photoelectric Photometry (IAPPP) conferences, books, and journal. The AAVSO developed a formal PEP program in the early 1980s. Its emphasis was on long-term monitoring of pulsating red giants. It was competing, not always successfully, with programs such as active sun-like binaries (RS CVn stars) which offered "instant gratification" in the form of publicity and quick publications. Nevertheless, the AAVSO PEP program has, through careful organization, motivation, and feedback to observers, produced extensive scientific results. In this presentation, I shall describe, as examples, my own work, its scientific significance, its educational benefit to dozens of my students, and its satisfaction to the observers. To some extent, the AAVSO PEP program has been superceded by its CCD program, but there is still a useful place for ongoing PEP observations of thousands of variable stars. Reference: Acknowledgements: I thank NSERC Canada for research support, my students, and AAVSO staff and observers, especially Howard Landis.

  11. Optical photometry of TX0506+056 (United States)

    Keel, William; Santander, Marcos


    The blazar TX0506+056 has attracted recent attention through its location in the error box of a high-energy Ice Cube neutrino detection ( and gamma-ray flaring (Atel #10791) We report recent photometry of TX0506+056 obtained in Johnson V and Cousins R passbands using the 1-meter Kapteyn telescope at La Palma, operated remotely by the SARA consortium.

  12. Lightcurve Photometry Opportunities: 2017 July-September (United States)

    Warner, Brian D.; Harris, Alan W.; Durech, Josef; Benner, Lance A. M.


    We present lists of asteroid photometry opportunities for objects reaching a favorable apparition and having either none or poorly-defined lightcurve parameters. Additional data on these objects will help with shape and spin axis modeling via lightcurve inversion. We also include lists of objects that will be the target of radar observations. Lightcurves for these objects can help constrain pole solutions and/or remove rotation period ambiguities that might not come from using radar data alone.

  13. Lightcurve Photometry Opportunities: 2017 January-March (United States)

    Warner, Brian D.; Harris, Alan W.; Durech, Josef; Benner, Lance A. M.


    We present lists of asteroid photometry opportunities for objects reaching a favorable apparition and having either none or poorly-defined lightcurve parameters. Additional data on these objects will help with shape and spin axis modeling via lightcurve inversion. We also include lists of objects that will be the target of radar observations. Lightcurves for these objects can help constrain pole solutions and/or remove rotation period ambiguities that might not come from using radar data alone.

  14. Lightcurve Photometry Opportunities: 2017 October-December (United States)

    Warner, Brian D.; Harris, Alan W.; Durech, Josef; Benner, Lance A. M.


    We present lists of asteroid photometry opportunities for objects reaching a favorable apparition and having either none or poorly-defined lightcurve parameters. Additional data on these objects will help with shape and spin axis modeling via lightcurve inversion. We also include lists of objects that will be the target of radar observations. Lightcurves for these objects can help constrain pole solutions and/or remove rotation period ambiguities that might not come from using radar data alone.

  15. Lightcurve Photometry Opportunities: 2017 April-June (United States)

    Warner, Brian D.; Harris, Alan W.; Durech, Josef; Benner, Lance A. M.


    We present lists of asteroid photometry opportunities for objects reaching a favorable apparition and having either none or poorly-defined lightcurve parameters. Additional data on these objects will help with shape and spin axis modeling via lightcurve inversion. We also include lists of objects that will be the target of radar observations. Lightcurves for these objects can help constrain pole solutions and/or remove rotation period ambiguities that might not come from using radar data alone.

  16. Improved moving source photometry with TRIPPy (United States)

    Alexandersen, Mike; Fraser, Wesley Cristopher


    Photometry of moving sources is more complicated than for stationary sources, because the sources trail their signal out over more pixels than a point source of the same magnitude. Using a circular aperture of same size as would be appropriate for point sources can cut out a large amount of flux if a moving source moves substantially relative to the size of the aperture during the exposure, resulting in underestimated fluxes. Using a large circular aperture can mitigate this issue at the cost of a significantly reduced signal to noise compared to a point source, as a result of the inclusion of a larger background region within the aperture.Trailed Image Photometry in Python (TRIPPy) solves this problem by using a pill-shaped aperture: the traditional circular aperture is sliced in half perpendicular to the direction of motion and separated by a rectangle as long as the total motion of the source during the exposure. TRIPPy can also calculate the appropriate aperture correction (which will depend both on the radius and trail length of the pill-shaped aperture), and has features for selecting good PSF stars, creating a PSF model (convolved moffat profile + lookup table) and selecting a custom sky-background area in order to ensure no other sources contribute to the background estimate.In this poster, we present an overview of the TRIPPy features and demonstrate the improvements resulting from using TRIPPy compared to photometry obtained by other methods with examples from real projects where TRIPPy has been implemented in order to obtain the best-possible photometric measurements of Solar System objects. While TRIPPy has currently mainly been used for Trans-Neptunian Objects, the improvement from using the pill-shaped aperture increases with source motion, making TRIPPy highly relevant for asteroid and centaur photometry as well.

  17. Astrometrica: Astrometric data reduction of CCD images (United States)

    Raab, Herbert


    Astrometrica is an interactive software tool for scientific grade astrometric data reduction of CCD images. The current version of the software is for the Windows 32bit operating system family. Astrometrica reads FITS (8, 16 and 32 bit integer files) and SBIG image files. The size of the images is limited only by available memory. It also offers automatic image calibration (Dark Frame and Flat Field correction), automatic reference star identification, automatic moving object detection and identification, and access to new-generation star catalogs (PPMXL, UCAC 3 and CMC-14), in addition to online help and other features. Astrometrica is shareware, available for use for a limited period of time (100 days) for free; special arrangements can be made for educational projects.

  18. Programmable Clock Waveform Generation for CCD Readout

    Energy Technology Data Exchange (ETDEWEB)

    Vicente, J. de; Castilla, J.; Martinez, G.; Marin, J.


    Charge transfer efficiency in CCDs is closely related to the clock waveform. In this paper, an experimental framework to explore different FPGA based clock waveform generator designs is described. Two alternative design approaches for controlling the rise/fall edge times and pulse width of the CCD clock signal have been implemented: level-control and time-control. Both approaches provide similar characteristics regarding the edge linearity and noise. Nevertheless, dissimilarities have been found with respect to the area and frequency range of application. Thus, while the time-control approach consumes less area, the level control approach provides a wider range of clock frequencies since it does not suffer capacitor discharge effect. (Author) 8 refs.

  19. UBV photometry of the Ap variable UZ Psc = HD 10783 (United States)

    Hardie, Robert H.; Reichmann, Edwin J.; Burke, Edward W., Jr.; Hall, Douglas S.


    The photometric variability of the Ap star HD 10783 = UZ Psc is discussed. New UBV photometry, obtained between late 1965 and early 1969, is presented and it is combined with existing published photometry to derive an improved ephemeris for times of maximum brightness: 2439758.00 + 4d.1328 n. It is concluded that the results are not very sensitive to the small shifts applied to the blue photometry.

  20. Low-noise video amplifiers for imaging CCD's (United States)

    Scinicariello, F.


    Various techniques were developed which enable the CCD (charge coupled device) imaging array user to obtain optimum performance from the device. A CCD video channel was described, and detector-preamplifier interface requirements were examined. A noise model for the system was discussed at length and laboratory data presented and compared to predicted results.

  1. Jonckheere Double Star Photometry - Part IV: Cetus (United States)

    Knapp, Wilfried


    If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part of them have magnitudes which are obviously far too bright. This report covers the Jonckheere objects in the constellation Cet. Only one image per object was taken as despite the risk of random effects even a single measurement is better than the currently usually given estimation although the J-objects in this southern constellation are better covered with observations as usual for Jonckheere doubles.

  2. Jonckheere Double Star Photometry - Part V: Cancer (United States)

    Knapp, Wilfried


    If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part of them have magnitudes which are obviously far too bright. This report covers the Jonckheere objects in the constellation Cancer. Only one image per object was taken as despite the risk of random effects even a single measurement is better than the currently usually given estimation, although the J-objects in this constellation seem with some exceptions better covered with observations as usual for Jonckheere doubles.

  3. High-resolution CCD imagers using area-array CCD's for sensing spectral components of an optical line image (United States)

    Elabd, Hammam (Inventor); Kosonocky, Walter F. (Inventor)


    CCD imagers with a novel replicated-line-imager architecture are abutted to form an extended line sensor. The sensor is preceded by optics having a slit aperture and having an optical beam splitter or astigmatic lens for projecting multiple line images through an optical color-discriminating stripe filter to the CCD imagers. A very high resolution camera suitable for use in a satellite, for example, is thus provided. The replicated-line architecture of the imager comprises an area-array CCD, successive rows of which are illuminated by replications of the same line segment, as transmitted by respective color filter stripes. The charge packets formed by accumulation of photoresponsive charge in the area-array CCD are read out row by row. Each successive row of charge packets is then converted from parallel to serial format in a CCD line register and its amplitude sensed to generate a line of output signal.

  4. and dioxouranium(vi)

    African Journals Online (AJOL)


    Thorium(IV) and uranium(VI) with atomic radii of 1.65 and .... to ν(NH) vibrations. Practically no effect on these frequencies after complexation precludes the possibility of metal-coordination at this group. The absorptions at 1600 ... observation suggests involvement of unsaturated nitrogen atoms of the two azomethine groups.

  5. The RSA survey of dwarf galaxies, 1: Optical photometry (United States)

    Vader, J. Patricia; Chaboyer, Brian


    We present detailed surface photometry, based on broad B-band charge coupled device (CCD) images, of about 80 dwarf galaxies. Our sample represents approximately 10% of all dwarf galaxies identified in the vicinity of Revised Shapley-Ames (RSA) galaxies on high resolution blue photographic plates, referred to as the RSA survey of dwarf galaxies. We derive global properties and radial surface brightness profiles, and examine the morphologies. The radial surface brightness profiles of dwarf galaxies, whether early or late type, display the same varieties in shape and complexity as those of classical giant galaxies. Only a few are well described by a pure r(exp 1/4) law. Exponential profiles prevail. Features typical of giant disk galaxies, such as exponential profiles with a central depression, lenses, and even, in one case (IC 2041), a relatively prominent bulge are also found in dwarf galaxies. Our data suggest that the central region evolves from being bulge-like, with an r(exp 1/4) law profile, in bright galaxies to a lens-like structure in dwarf galaxies. We prove detailed surface photometry to be a helpful if not always sufficient tool in investigating the structure of dwarf galaxies. In many cases kinematic information is needed to complete the picture. We find the shapes of the surface brightness profiles to be loosely associated with morphological type. Our sample contains several new galaxies with properties intermediate between those of giant and dwarf ellipticals (but no M32-like objects). This shows that such intermediate galaxies exist so that at least a fraction of early-type dwarf ellipticals is structurally related to early-type giants instead of belonging to a totally unrelated, disjunct family. This supports an origin of early-type dwarf galaxies as originally more massive systems that acquired their current morphology as a result of substantial, presumable supernova-driven, mass loss. On the other hand, several early-type dwarfs in our sample are

  6. High-precision photometry by telescope defocussing - VI. WASP-24, WASP-25 and WASP-26

    DEFF Research Database (Denmark)

    Southworth, John; Hinse, T. C.; Burgdorf, M.


    We present time series photometric observations of 13 transits in the planetary systems WASP-24, WASP-25 and WASP-26. All three systems have orbital obliquity measurements, WASP-24 and WASP-26 have been observed with Spitzer, and WASP-25 was previously comparatively neglected. Our light curves we...

  7. Homogeneous Photometry VI: Variable Stars in the Leo I Dwarf Spheroidal Galaxy (United States)

    Stetson, Peter B.; Fiorentino, Giuliana; Bono, Giuseppe; Bernard, Edouard J.; Monelli, Matteo; Iannicola, Giacinto; Gallart, Carme; Ferraro, Ivan


    We have characterized the pulsation properties of 164 candidate RR Lyrae variables (RRLs) and 55 candidate Anomalous and/or short-period Cepheids in Leo I dwarf spheroidal galaxy. On the basis of its RRLs Leo I is confirmed to be an Oosterhoff-intermediate type galaxy, like several other dwarfs. We show that in their pulsation properties, the RRLs representing the oldest stellar population in the galaxy are not significantly different from those of five other nearby, isolated dwarf spheroidal galaxies. A similar result is obtained when comparing them to RR Lyrae stars in recently discovered ultra-faint dwarf galaxies. We are able to compare the period distributions and period-amplitude relations for a statistically significant sample of ab type RR Lyrae stars in dwarf galaxies (~1300stars) with those in the Galactic halo field (~14,000stars) and globular clusters (~1000stars). Field RRLs show a significant change in their period distribution when moving from the inner (dG14kpc) halo regions. This suggests that the halo formed from (at least) two dissimilar progenitors or types of progenitor. Considered together, the RRLs in classical dwarf spheroidal and ultra-faint dwarf galaxies-as observed today-do not appear to follow the well defined pulsation properties shown by those in either the inner or the outer Galactic halo, nor do they have the same properties as RRLs in globular clusters. In particular, the samples of fundamental-mode RRLs in dwarfs seem to lack High Amplitudes and Short Periods ("HASP":AV>1.0mag and P <0.48d) when compared with those observed in the Galactic halo field and globular clusters. The observed properties of RRLs do not support the idea that currently existing classical dwarf spheroidal and ultra-faint dwarf galaxies are surviving representative examples of the original building blocks of the Galactic halo.

  8. Radiation events in astronomical CCD images

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.R.; McDonald, R.J.; Hurley, D.L.; Holland, S.E.; Groom, D.E.; Brown, W.E.; Gilmore, D.K.; Stover, R.J.; Wei, M.


    The remarkable sensitivity of depleted silicon to ionizing radiation is a nuisance to astronomers. ''Cosmic rays'' degrade images because of struck pixels, leading to modified observing strategies and the development of algorithms to remove the unwanted artifacts. In the new-generation CCD's with thick sensitive regions, cosmic-ray muons make recognizable straight tracks and there is enhanced sensitivity to ambient gamma radiation via Compton-scattered electrons (''worms''). Beta emitters inside the dewar, for example high-potassium glasses such as BK7, also produce worm-like tracks. The cosmic-ray muon rate is irreducible and increases with altitude. The gamma rays are mostly by-products of the U and Th decay chains; these elements always appear as traces in concrete and other materials. The Compton recoil event rate can be reduced significantly by the choice of materials in the environment and dewar and by careful shielding. Telescope domes appear to be significantly cleaner than basement laboratories and Coude spectrograph rooms. Radiation sources inside the dewar can be eliminated by judicious choice of materials. Cosmogenic activation during high-altitude flights does not appear to be a problem. Our conclusions are supported by tests at the Lawrence Berkeley National Laboratory low-level counting facilities in Berkeley and at Oroville, California (180 m underground).

  9. Linearity measurement for image-intensified CCD (United States)

    Zhao, Yuhuan; Zhang, Liwei; Yan, Feng; Gu, Yongqiang; Wan, Liying


    To the characteristic of the ultraviolet CCD (UV ICCD), technique of the linearity measurement of the UV ICCD camera is studied based on the theory of radiometry. Approach of linearity measurement is discussed, and a kind of measurement system of the UV ICCD has been developed based on the method of neutral density filter. It is very important that the transmittance of the filter is independent of the wavelength in the method of neutral density filter. Black metal screen mesh with different transmittance is used in our system, and calibration of the filters' transmittance in different working positions has been done. Meanwhile, to assure the uniform of the received radiation on the target of the detector at any test points, an integrating sphere is placed behind the neutral filter to balance light. The whole measurement system mainly consists of a deuterium lamp with high stabilization, the attenuation film with transmission, integrating sphere, optical guide and electro-shift platform. Auto control is realized via special software during the test. With this instrument, the linearity of the UV ICCD was measured. Experimental results show that the nonlinearity of the UV ICCD under fixed-gain is less than 2% and the uncertainty of measurement system is less than 4%.

  10. II-VI semiconductor compounds

    CERN Document Server


    For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

  11. CCD charge collection efficiency and the photon transfer technique (United States)

    Janesick, J.; Klaasen, K.; Elliott, T.


    The charge-coupled device (CCD) has shown unprecendented performance as a photon detector in the areas of spectral response, charge transfer, and readout noise. Recent experience indicates, however, that the full potential for the CCD's charge collection efficiency (CCE) lies well beyond that which is realized in currently available devices. A definition of CCE performance is presented and a standard test tool (the photon transfer technique) for measuring and optimizing this important CCD parameter is introduced. CCE characteristics for different types of CCDs are compared; the primary limitations in achieving high CCE performance are discussed, and the prospects for future improvement are outlined.

  12. VizieR Online Data Catalog: BVR photometry of EPIC 211957146 (Sriram+, 2017) (United States)

    Sriram, K.; Malu, S.; Choi, C. S.; Vivekananda Rao, P.


    Photometric observations of the variable EPIC 211957146 in the R band were taken using the IUCAA-Girawali Observatory (IGO) 2m telescope from 2015 February 5-22, for 5 nights (specifications of IGO 2m telescope CCD are as discussed in Sriram et al. 2016AJ....151...69S). An exposure time of 20-30s was given for imaging. B and V band observations were taken from the JCBT 1.3m telescope at Vainu Bappu Observatory (VBO) during 2016 February 3-8 and 2016 March 25-April 3 for a total of 7 nights. The JCBT 1.3m DFM telescope at VBO uses a 2K*4K UKATC CCD having a gain of 0.745e-/ADU and a read out noise of 4.2e-. The plate scale is 0.3arcsec/pixel resulting in an image of 10'*20' and images of the source in the B and V bands were taken with an integration time of 120s. Differential photometry was performed on the variable, with the comparison and check stars (of similar brightness) lying close to the variable. This source was also observed by the Kepler K2 mission Campaign 5, and the data were acquired from the MAST portal and the NASA Exoplanet Archive. K2 campaign 5 monitored the sky for a duration of ~74days and was fixed upon a single boresight position of 08h40m38s, +16°49'47'' starting from 2015 April 27 to July 10. Spectroscopic observation of the variable was performed during the nights of 2016 January 29-30 using the 2m Himalaya Chandra Telescope (HCT, IAO) equipped with the Himalaya Faint Object Spectrograph Camera (HFOSC) having a 2K*4K CCD. Spectra were obtained with an exposure time of 1800-2700s for both variable and spectrophotometric standard stars (BD+08 2015). A few spectra were also taken on 2016 February 1 using the Optomechanics Research spectrograph mounted on the 2.3m Vainu Bappu Telescope using a 1K*1K CCD. A 600lines/mm grating spanning a wavelength range of 2000-8000Å with a dispersion of 2.6Å/pixel and a resolution of ~5.3Å was used. The same spectrophotometric standard as before was used for observation, and an exposure time of 2700s was

  13. Multiaperture U BV RIzJHK Photometry of Galaxies in the Coma Cluster

    Energy Technology Data Exchange (ETDEWEB)

    Eisenhardt, P R; De Propris, R; Gonzalez, A H; Stanford, S A; Dickinson, M; Wang, M C


    We present a set of UBV RIzJHKs photometry for 745 J +H band selected objects in a 22:5{prime} x 29:2{prime} region centered on the core of the Coma cluster. This includes 516 galaxies and is at least 80% complete to H = 16, with a spectroscopically complete sample of 111 cluster members (nearly all with morphological classification) for H < 14:5. For each object we present total Kron (1980) magnitudes and aperture photometry. As an example, we use these data to derive color-magnitude relations for Coma early-type galaxies, measure the intrinsic scatter of these relations and its dependence on galaxy mass, and address the issue of color gradients. We find that the color gradients are mild and that the intrinsic scatter about the color-magnitude relation is small ({approx} 0:05 mag in U-V and less than {approx} 0:03 in B-R, V-I, or J-K). There is no evidence that the intrinsic scatter varies with galaxy luminosity, suggesting that the cluster red sequence is established at early epochs over a range of {approx} 100 in stellar mass.

  14. Enzymatic study on AtCCD4 and AtCCD7 and their potential to form acyclic regulatory metabolites

    KAUST Repository

    Bruno, Mark


    The Arabidopsis carotenoid cleavage dioxygenase 4 (AtCCD4) is a negative regulator of the carotenoid content of seeds and has recently been suggested as a candidate for the generation of retrograde signals that are thought to derive from the cleavage of poly-cis-configured carotene desaturation intermediates. In this work, we investigated the activity of AtCCD4 in vitro and used dynamic modeling to determine its substrate preference. Our results document strict regional specificity for cleavage at the C9–C10 double bond in carotenoids and apocarotenoids, with preference for carotenoid substrates and an obstructing effect on hydroxyl functions, and demonstrate the specificity for all-trans-configured carotenes and xanthophylls. AtCCD4 cleaved substrates with at least one ionone ring and did not convert acyclic carotene desaturation intermediates, independent of their isomeric states. These results do not support a direct involvement of AtCCD4 in generating the supposed regulatory metabolites. In contrast, the strigolactone biosynthetic enzyme AtCCD7 converted 9-cis-configured acyclic carotenes, such as 9-cis-ζ-carotene, 9\\'-cis-neurosporene, and 9-cis-lycopene, yielding 9-cis-configured products and indicating that AtCCD7, rather than AtCCD4, is the candidate for forming acyclic retrograde signals.

  15. UV-sensitive scientific CCD image sensors (United States)

    Vishnevsky, Grigory I.; Kossov, Vladimir G.; Iblyaminova, A. F.; Lazovsky, Leonid Y.; Vydrevitch, Michail G.


    An investigation of probe laser irradiation interaction with substances containing in an environment has long since become a recognized technique for contamination detection and identification. For this purpose, a near and midrange-IR laser irradiation is traditionally used. However, as many works presented on last ecology monitoring conferences show, in addition to traditional systems, rapidly growing are systems with laser irradiation from near-UV range (250 - 500 nm). Use of CCD imagers is one of the prerequisites for this allowing the development of a multi-channel computer-based spectral research system. To identify and analyze contaminating impurities on an environment, such methods as laser fluorescence analysis, UV absorption and differential spectroscopy, Raman scattering are commonly used. These methods are used to identify a large number of impurities (petrol, toluene, Xylene isomers, SO2, acetone, methanol), to detect and identify food pathogens in real time, to measure a concentration of NH3, SO2 and NO in combustion outbursts, to detect oil products in a water, to analyze contaminations in ground waters, to define ozone distribution in the atmosphere profile, to monitor various chemical processes including radioactive materials manufacturing, heterogeneous catalytic reactions, polymers production etc. Multi-element image sensor with enhanced UV sensitivity, low optical non-uniformity, low intrinsic noise and high dynamic range is a key element of all above systems. Thus, so called Virtual Phase (VP) CCDs possessing all these features, seems promising for ecology monitoring spectral measuring systems. Presently, a family of VP CCDs with different architecture and number of pixels is developed and being manufactured. All CCDs from this family are supported with a precise slow-scan digital image acquisition system that can be used in various image processing systems in astronomy, biology, medicine, ecology etc. An image is displayed directly on a PC

  16. VI Nukitsa konkurss

    Index Scriptorium Estoniae


    VI Nukitsa konkursi auhinnad: Kirjanikud: I - Henno Käo ("Kusagil mujal"); II - Aidi Vallik ("Kuidas elad, Ann?"); III - Artur Jurin ("Piletijaht: uued segadused Kilulibeda teel"). Kunstnikud: I - Karel Korp (Leelo Tungla ja Karel Korbi "Tema amet"); II - Edgar Valter ("Kuidas õppida vaatama?"); III - Artur Jurin - ("Piletijaht: uued segadused Kilulibeda teel"). Täiskasvanute küsitluse võitis nii teksti kui piltidega Ene-Maris Tali ja Tarmo Tali "Tähtraamat. Aastaring Maarjamaal"

  17. Target Image Matching Algorithm Based on Binocular CCD Ranging

    Directory of Open Access Journals (Sweden)

    Dongming Li


    Full Text Available This paper proposed target image in a subpixel level matching algorithm for binocular CCD ranging, which is based on the principle of binocular CCD ranging. In the paper, firstly, we introduced the ranging principle of the binocular ranging system and deduced a binocular parallax formula. Secondly, we deduced the algorithm which was named improved cross-correlation matching algorithm and cubic surface fitting algorithm for target images matched, and it could achieve a subpixel level matching for binocular CCD ranging images. Lastly, through experiment we have analyzed and verified the actual CCD ranging images, then analyzed the errors of the experimental results and corrected the formula of calculating system errors. Experimental results showed that the actual measurement accuracy of a target within 3 km was higher than 0.52%, which meet the accuracy requirements of the high precision binocular ranging.


    National Aeronautics and Space Administration — This data set presents images of 26P/Grigg-Skjellerup obtained by various observers at several ground-based observatories using CCD instruments. These data have not...

  19. Micrometer and CCD measurements of double stars (Series 51

    Directory of Open Access Journals (Sweden)

    Popović G.M.


    Full Text Available 36 micrometric measurements of 20 double or multiple systems carried out with the Zeiss 65/1055 cm Refractor of Belgrade Observatory are communicated. Also 35 CCD measurements of 15 double or multiple systems are included.

  20. Correlation and image compression for limited-bandwidth CCD.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Douglas G.


    As radars move to Unmanned Aerial Vehicles with limited-bandwidth data downlinks, the amount of data stored and transmitted with each image becomes more significant. This document gives the results of a study to determine the effect of lossy compression in the image magnitude and phase on Coherent Change Detection (CCD). We examine 44 lossy compression types, plus lossless zlib compression, and test each compression method with over 600 CCD image pairs. We also derive theoretical predictions for the correlation for most of these compression schemes, which compare favorably with the experimental results. We recommend image transmission formats for limited-bandwidth programs having various requirements for CCD, including programs which cannot allow performance degradation and those which have stricter bandwidth requirements at the expense of CCD performance.

  1. Collection and processing data for high quality CCD images.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter


    Coherent Change Detection (CCD) with Synthetic Aperture Radar (SAR) images is a technique whereby very subtle temporal changes can be discerned in a target scene. However, optimal performance requires carefully matching data collection geometries and adjusting the processing to compensate for imprecision in the collection geometries. Tolerances in the precision of the data collection are discussed, and anecdotal advice is presented for optimum CCD performance. Processing considerations are also discussed.

  2. The NOAO Data Lab PHAT Photometry Database (United States)

    Olsen, Knut; Williams, Ben; Fitzpatrick, Michael; PHAT Team


    We present a database containing both the combined photometric object catalog and the single epoch measurements from the Panchromatic Hubble Andromeda Treasury (PHAT). This database is hosted by the NOAO Data Lab (, and as such exposes a number of data services to the PHAT photometry, including access through a Table Access Protocol (TAP) service, direct PostgreSQL queries, web-based and programmatic query interfaces, remote storage space for personal database tables and files, and a JupyterHub-based Notebook analysis environment, as well as image access through a Simple Image Access (SIA) service. We show how the Data Lab database and Jupyter Notebook environment allow for straightforward and efficient analyses of PHAT catalog data, including maps of object density, depth, and color, extraction of light curves of variable objects, and proper motion exploration.

  3. Supernova Classification Using Swift UVOT Photometry (United States)

    Smith, Madison; Brown, Peter J.


    With the great influx of supernova discoveries over the past few years, the observation time needed to acquire the spectroscopic data needed to classify supernova by type has become unobtainable. Instead, using the photometry of supernovae could greatly reduce the amount of time between discovery and classification. For this project we looked at the relationship between colors and supernova types through machine learning packages in Python. Using data from the Swift Ultraviolet/Optical Telescope (UVOT), each photometric point was assigned values corresponding to colors, absolute magnitudes, and the relative times from the peak brightness in several filters. These values were fed into three classifying methods, the nearest neighbors, decision tree, and random forest methods. We will discuss the success of these classification systems, the optimal filters for photometric classification, and ways to improve the classification.

  4. Extended Aperture Photometry of K2 RR Lyrae stars

    Directory of Open Access Journals (Sweden)

    Plachy Emese


    Full Text Available We present the method of the Extended Aperture Photometry (EAP that we applied on K2 RR Lyrae stars. Our aim is to minimize the instrumental variations of attitude control maneuvers by using apertures that cover the positional changes in the field of view thus contain the stars during the whole observation. We present example light curves that we compared to the light curves from the K2 Systematics Correction (K2SC pipeline applied on the automated Single Aperture Photometry (SAP and on the Pre-search Data Conditioning Simple Aperture Photometry (PDCSAP data.


    National Aeronautics and Space Administration — This data set contains aperture photometry of Kreutz sungrazing comets that were observed by the LASCO instrument on SOHO from 1996-2005. Apparent magnitude and the...


    National Aeronautics and Space Administration — This data set contains digitized photometry of the reflections off Io and Europa of the impact fireballs produced as the D, E, K, and N fragments of comet...


    National Aeronautics and Space Administration — This data set presents the photometry of comet 1P/Halley collected by the International Halley Watch (IHW) Infrared Studies Network (IRSN) over the period September...

  8. PHOBOS 2 MARS KRFM PHOTOMETRY V1.0 (United States)

    National Aeronautics and Space Administration — This data set consists of the set of visual and thermal infrared band photometry of Mars obtained by the KRFM experiment on the Phobos 2 spacecraft. The data are...


    National Aeronautics and Space Administration — This data set contains images of the Deep Space 1 target, comet 19P/Borrelly, and derived photometry from five consecutive nights of observing over 28 July - 1...

  10. Vi tror, vi forstår hinanden, men det gør vi ikke

    DEFF Research Database (Denmark)

    Boysen, Mikkel Snorre Wilms


    Vores verdensbillede er baseret på en tro på, at vi forstår hinanden. Men meget tyder på, at denne tro snarere er en illusion. Derfor må vi indstille os på, at der skal en særlig indsats til, hvis vi skal kunne forstå vores omverden og menneskene i den......Vores verdensbillede er baseret på en tro på, at vi forstår hinanden. Men meget tyder på, at denne tro snarere er en illusion. Derfor må vi indstille os på, at der skal en særlig indsats til, hvis vi skal kunne forstå vores omverden og menneskene i den...

  11. Visual enhancement of laparoscopic nephrectomies using the 3-CCD camera (United States)

    Crane, Nicole J.; Kansal, Neil S.; Dhanani, Nadeem; Alemozaffar, Mehrdad; Kirk, Allan D.; Pinto, Peter A.; Elster, Eric A.; Huffman, Scott W.; Levin, Ira W.


    Many surgical techniques are currently shifting from the more conventional, open approach towards minimally invasive laparoscopic procedures. Laparoscopy results in smaller incisions, potentially leading to less postoperative pain and more rapid recoveries . One key disadvantage of laparoscopic surgery is the loss of three-dimensional assessment of organs and tissue perfusion. Advances in laparoscopic technology include high-definition monitors for improved visualization and upgraded single charge coupled device (CCD) detectors to 3-CCD cameras, to provide a larger, more sensitive color palette to increase the perception of detail. In this discussion, we further advance existing laparoscopic technology to create greater enhancement of images obtained during radical and partial nephrectomies in which the assessment of tissue perfusion is crucial but limited with current 3-CCD cameras. By separating the signals received by each CCD in the 3-CCD camera and by introducing a straight forward algorithm, rapid differentiation of renal vessels and perfusion is accomplished and could be performed real time. The newly acquired images are overlaid onto conventional images for reference and comparison. This affords the surgeon the ability to accurately detect changes in tissue oxygenation despite inherent limitations of the visible light image. Such additional capability should impact procedures in which visual assessment of organ vitality is critical.

  12. Design, analysis, and testing of a CCD array mounting structure (United States)

    Sultana, John A.; O'Neill, Mark B.


    A method has been developed for mounting charge-coupled device (CCD) arrays in an optical telescope so as to minimize thermal defocusing errors. The mounting arrangement was developed for a six-inch aperture, visible band, off-axis reimaging telescope attached to an experimental satellite. The mounting arrangement consists of two pieces: a fiberglass frame which holds the actively cooled CCD package and provides thermal isolation from the telescope body; and a titanium flexure, which acts to minimize structural distortions caused by the difference in thermal expansion properties of the CCD array and the telescope body. This paper describes the design, analysis, and testing of this CCD array mounting arrangement. A detailed finite-element model of the CCD array and the mount was developed and used to predict thermally-induced defocus and gravity sag deformations, as well as natural frequencies. Experimental tests to verify the computer model results were performed using holographic interferometry. Vibration tests were also performed to verify the natural frequencies as well as structural integrity during launch. A comparison of the computer model predictions and the holographic interferometric measurements of thermally-induced defocussing indicates agreement to within 15 to 20%. Both the experimental and computer results indicate that the mounting structure provides focus stability over the operational temperature range of the telescope with sufficient structural integrity to survive the anticipated spacecraft launch loads.

  13. CCD Astrophotography High-Quality Imaging from the Suburbs

    CERN Document Server

    Stuart, Adam


    This is a reference book for amateur astronomers who have become interested in CCD imaging. Those glorious astronomical images found in astronomy magazines might seem out of reach to newcomers to CCD imaging, but this is not the case. Great pictures are attainable with modest equipment. Adam Stuart’s many beautiful images, reproduced in this book, attest to the quality of – initially – a beginner’s efforts. Chilled-chip astronomical CCD-cameras and software are also wonderful tools for cutting through seemingly impenetrable light-pollution. CCD Astrophotography from the Suburbs describes one man’s successful approach to the problem of getting high-quality astronomical images under some of the most light-polluted conditions. Here is a complete and thoroughly tested program that will help every CCD-beginner to work towards digital imaging of the highest quality. It is equally useful to astronomers who have perfect observing conditions, as to those who have to observe from light-polluted city skies.

  14. Purification and crystallization of Vibrio fischeri CcdB and its complexes with fragments of gyrase and CcdA

    Energy Technology Data Exchange (ETDEWEB)

    De Jonge, Natalie, E-mail:; Buts, Lieven; Vangelooven, Joris [Department of Molecular and Cellular Interactions, VIB, Pleinlaan 2, 1050 Brussels (Belgium); Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium); Mine, Natacha; Van Melderen, Laurence [Laboratoire de Génétique des Procaryotes, Institut de Biologie et de Médecine, Université Libre de Bruxelles, Gosselies (Belgium); Wyns, Lode; Loris, Remy [Department of Molecular and Cellular Interactions, VIB, Pleinlaan 2, 1050 Brussels (Belgium); Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium)


    A CcdB homologue from V. fischeri was overexpressed in E. coli and purified. The free protein was crystallized, as were its complexes with fragments of E. coli and V. fischeri gyrase and with the F-plasmid CcdA C-terminal domain. The ccd toxin–antitoxin module from the Escherichia coli F plasmid has a homologue on the Vibrio fischeri integron. The homologue of the toxin (CcdB{sub Vfi}) was crystallized in two different crystal forms. The first form belongs to space group I23 or I2{sub 1}3, with unit-cell parameter a = 84.5 Å, and diffracts to 1.5 Å resolution. The second crystal form belongs to space group C2, with unit-cell parameters a = 58.5, b = 43.6, c = 37.5 Å, β = 110.0°, and diffracts to 1.7 Å resolution. The complex of CcdB{sub Vfi} with the GyrA14{sub Vfi} fragment of V. fischeri gyrase crystallizes in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 53.5, b = 94.6, c = 58.1 Å, and diffracts to 2.2 Å resolution. The corresponding mixed complex with E. coli GyrA14{sub Ec} crystallizes in space group C2, with unit-cell parameters a = 130.1, b = 90.8, c = 58.1 Å, β = 102.6°, and diffracts to 1.95 Å. Finally, a complex between CcdB{sub Vfi} and part of the F-plasmid antitoxin CcdA{sub F} crystallizes in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 46.9, b = 62.6, c = 82.0 Å, and diffracts to 1.9 Å resolution.

  15. Photography and photographic-photometry of the solar aureole (United States)

    Deepak, A.; Adams, R. R.


    This paper describes procedures for taking solar aureole photographs with conventional small format (35- or 70-mm) cameras and films and discusses photographic-photometry techniques for obtaining accurate solar aureole radiance measurements from these photographs, the measurements being used for retrieving atmospheric aerosol characteristics. The photographic data reduction techniques discussed here include sensitometry, densitometry, off-axis illumination distribution measurement, photogrammetry and photometry relations, etc. Comparison tests show that photographic measurements of the solar aureole radiance agree well with simultaneous photoelectric measurements.

  16. CCD IMAGES OF 19P/BORRELLY, 1987-2002 (United States)

    National Aeronautics and Space Administration — This data set presents images and photometry of comet 19P/Borrelly 1 obtained by Karen Meech over 20 nights during the period 1987-08-21 to 2002-02-03. These data...

  17. Thinned back-illuminated CCD for x-ray microscopy (United States)

    Meyer-Ilse, Werner; Wilhein, Thomas; Guttmann, Peter


    X-ray microscopy requires image detectors for soft x-rays (2.4 nm to 4.5 nm wavelength) with high detective quantum efficiency for a low radiation dosage applied to the sample. A thinned backside illuminated CCD has been attached to the Gottingen x-ray microscope, which is installed at the BESSY electron storage ring in Berlin. The CCD was a commercially available device with 1024 by 1024 pixels (each 24 micrometers square) without the anti-reflecting coating, which is applied to the standard device. First experiments performed at the primarily used x- ray wavelength of 2.4 nm show a considerable reduction of exposure time compared to the previously used photographic emulsion. This greatly reduces the radiation dose applied to the sample specimen. There was no degradation in performance of the CCD detected after one week of operation.

  18. Noise analysis for CCD-based ultraviolet and visible spectrophotometry. (United States)

    Davenport, John J; Hodgkinson, Jane; Saffell, John R; Tatam, Ralph P


    We present the results of a detailed analysis of the noise behavior of two CCD spectrometers in common use, an AvaSpec-3648 CCD UV spectrometer and an Ocean Optics S2000 Vis spectrometer. Light sources used include a deuterium UV/Vis lamp and UV and visible LEDs. Common noise phenomena include source fluctuation noise, photoresponse nonuniformity, dark current noise, fixed pattern noise, and read noise. These were identified and characterized by varying light source, spectrometer settings, or temperature. A number of noise-limiting techniques are proposed, demonstrating a best-case spectroscopic noise equivalent absorbance of 3.5×10(-4)  AU for the AvaSpec-3648 and 5.6×10(-4)  AU for the Ocean Optics S2000 over a 30 s integration period. These techniques can be used on other CCD spectrometers to optimize performance.

  19. Photometry and imaging of Comet 103P/Hartley in the 2010-2011 apparition (United States)

    Milani, Giannantonio; Bryssinck, Erik; Nicolini, Martino; Mikuž, Herman; Sostero, Giovanni; Bacci, Paolo; Borghini, Walter; Castellano, Dario; Facchini, Mauro; Favero, Giancarlo; Galli, Gianni; Guido, Ernesto; Hausler, Bernhard; Hornoch, Kamil; Howes, Nick; Ligustri, Rolando; Perrella, Carmen; Prosperi, Enrico; Skvarč, Jure; Srba, Jiří; Trabatti, Roberto; Vinante, Carlo; Szabó, Gyula


    The results of a CARA (Cometary Archive for Afρ) campaign on Comet 103P/Hartley 2 are presented. The main goal was to monitor extensively the comet during the apparition with CCD R and I imaging and photometry, as a support of EPOXI mission. The Afρ quantity showed a progressively rising ascending branch, followed by an apparent flat maximum that lasted for 2 months, from about -10 to +50 days from perihelion. In this period, Afρ peaked at around 100 cm in R band with strong short term fluctuations between 70 and 140 cm. Early signs of activity were detectable well before perihelion (about 80-90 days before) and a random variability is also present in the descending branch after perihelion. Three post perihelion data points (between +55 and +61 days) from the 1997-1998 apparition show a bit higher Afρ value of our observation and a similar fast variation. The average Afρ behavior, corrected for the solar phase effect, is strongly asymmetric and shows a more steeper ascending branch, approaching to perihelion. Morphology and coma asymmetry, as well as the sunward and tailward profiles are examined. An average gradient indicatively between ˜ρ-0.7 and ρ-1 is observed in the inner coma (ρ < 2000 km). Ten small amplitude outbursts have been detected and two ones were suspected.

  20. DepAstroCCD an original astrometric tool

    Directory of Open Access Journals (Sweden)

    Stojanović I.


    Full Text Available A complex software for preparation and treatment of astro photographic plates and double-star observations recorded with CCD cameras is developed. The preparation interface contains a catalogue base for the choice of observation objects and an interface for bringing into accordance the telescope and CCD camera performance with the assumptions of the postprocessor interface. The processing is based on the original development of image gradient removing software and classical FFT method and autocorrelation. The software has been tested on several theoretical and real images of double stars.

  1. Technology validation of the PLATO CCD at ESA (United States)

    Prod'homme, Thibaut; Verhoeve, Peter; Beaufort, Thierry; Duvet, Ludovic; Lemmel, Frederic; Smit, Hans; Blommaert, Sander; Oosterbroek, Tim; van der Luijt, Cornelis; Visser, Ivo; Heijnen, Jerko; Butler, Bart


    PLATO { PLAnetary Transits and Oscillations of stars { is the third medium-class mission to be selected in the European Space Agency (ESA) Science and Robotic Exploration Cosmic Vision programme. Due for launch in 2025, the payload makes use of a large format (8 cm x 8 cm) Charge-Coupled Devices (CCDs) the e2v CCD270 operated at 4 MHz. The manufacture of such large device in large quantity constitutes an unprecedented effort. To de-risk the PLATO CCD procurement and aid the mission definition process, ESA's Payload Technology Validation team is characterizing the electro-optical performance of a number of PLATO devices before and after proton irradiation.

  2. ESA's CCD test bench for the PLATO mission (United States)

    Beaufort, Thierry; Duvet, Ludovic; Bloemmaert, Sander; Lemmel, Frederic; Prod'homme, Thibaut; Verhoeve, Peter; Smit, Hans; Butler, Bart; van der Luijt, Cornelis; Heijnen, Jerko; Visser, Ivo


    PLATO { PLAnetary Transits and Oscillations of stars { is the third medium-class mission to be selected in the European Space Agency (ESA) Science and Robotic Exploration Cosmic Vision programme. Due for launch in 2025, the payload makes use of a large format (8 cm x 8 cm) Charge-Coupled Devices (CCDs), the e2v CCD270 operated at 4 MHz and at -70 C. To de-risk the PLATO CCD qualification programme initiated in 2014 and support the mission definition process, ESA's Payload Technology Validation section from the Future Missions Office has developed a dedicated test bench.

  3. Digital Printing Quality Detection and Analysis Technology Based on CCD (United States)

    He, Ming; Zheng, Liping


    With the help of CCD digital printing quality detection and analysis technology, it can carry out rapid evaluation and objective detection of printing quality, and can play a certain control effect on printing quality. It can be said CDD digital printing quality testing and analysis of the rational application of technology, its digital printing and printing materials for a variety of printing equipments to improve the quality of a very positive role. In this paper, we do an in-depth study and discussion based on the CCD digital print quality testing and analysis technology.

  4. Investigating the Bright End of LSST Photometry (United States)

    Ojala, Elle; Pepper, Joshua; LSST Collaboration


    The Large Synoptic Survey Telescope (LSST) will begin operations in 2022, conducting a wide-field, synoptic multiband survey of the southern sky. Some fraction of objects at the bright end of the magnitude regime observed by LSST will overlap with other wide-sky surveys, allowing for calibration and cross-checking between surveys. The LSST is optimized for observations of very faint objects, so much of this data overlap will be comprised of saturated images. This project provides the first in-depth analysis of saturation in LSST images. Using the PhoSim package to create simulated LSST images, we evaluate saturation properties of several types of stars to determine the brightness limitations of LSST. We also collect metadata from many wide-field photometric surveys to provide cross-survey accounting and comparison. Additionally, we evaluate the accuracy of the PhoSim modeling parameters to determine the reliability of the software. These efforts will allow us to determine the expected useable data overlap between bright-end LSST images and faint-end images in other wide-sky surveys. Our next steps are developing methods to extract photometry from saturated images.This material is based upon work supported in part by the National Science Foundation through Cooperative Agreement 1258333 managed by the Association of Universities for Research in Astronomy (AURA), and the Department of Energy under Contract No. DE-AC02-76SF00515 with the SLAC National Accelerator Laboratory. Additional LSST funding comes from private donations, grants to universities, and in-kind support from LSSTC Institutional Members.Thanks to NSF grant PHY-135195 and the 2017 LSSTC Grant Award #2017-UG06 for making this project possible.

  5. Astrometric meaning and interpretation of high-precision time delay integration CCD data (United States)

    Bastian, U.; Biermann, M.


    We investigate the astrometric content of CCD charge images of stars collected in time delay integration (TDI) mode with a scanning (rotating) telescope. We focus on the ESA astrometric space mission Gaia, but the results are valid for other scanning telescopes too. The physical attitude of the telescope is shown to be unobservable. Instead, an effective astrometric attitude is observed which represents an average over the TDI exposure time. The effective astrometric attitudes “seen” by different instruments (in case of Gaia: Astro, Spectro, Astro with gates) differ in a non-trivial way. If e.g. the high-precision Astro attitude would be used for the astrometric exploitation of the Spectro data, the Spectro CCDs would be “seen” to float around on the focal plane by several milli-arcseconds. In addition we find that the TDI mode produces an attitude jitter with the period of TDI clocking. We prove that this is negligibly small in the case of Gaia. We point out that the effective instant of observation is not the instant of charge read-out from the CCDs, but about half an exposure time (i.e. up to a few seconds) earlier. This is particularly important for the astrometry of solar-system objects and for the photometry of rapidly varying objects. It is also relevant for all other objects because of the time dependence of aberration. It is not clear whether the differences between the astrometric attitudes of different instruments require separate attitude reconstructions, but an approximate transformation from Astro to Spectro probably will be sufficient.

  6. Astrometric CCD Observations of Three Double Stars Measurements (United States)

    Nand, Angela


    CCD astrometric observations of three double star groups from the Orion constellation were made. Position angles and separations of corresponding pairs were obtained from the data acquired and compared to previous observations listed in the Washington Double Star Catalog. Present data agrees with previous observational data.

  7. CCD Measurements of WDS 13510+6819 STTA127 (United States)

    Alzaben, Faisal; Vasilenko, Dmitrii; Ganbold, Gunbold; McClanahan, Stuart; Boyce, Pat; Boyce, Grady


    WDS 13510+6819, a three-star star system, discoverer code STTA 127, is imaged using CCD cameras for astrometric measurements in comparison to historic data contained in the Washington Double Star Catalog. The historical data outlines measurements between the A-B and the B-C components and the 2016 measurements support the trend outlined in the WDS Historical File.

  8. Developments in X-ray and astronomical CCD imagers

    CERN Document Server

    Gregory, J A; Kosicki, B B; Reich, R K


    There have been many recent developments in the attributes and capabilities of silicon-based CCD detectors for use in space and ground-based astronomy. The imagers used as X-ray detectors require very low noise and excellent quantum efficiency over the energy range of 200-10000 eV. This is achieved using a combination of front and back-illuminated imagers fabricated on a 5000 OMEGA-cm resistivity material. A requirement for ground-based imagers is very good sensitivity between 350 and 1000 nm, as well as low noise and a high degree of spatial uniformity. We will describe the fabrication and performance of these imagers. Special features integrated into the CCD pixel architecture have increased the capability of the imagers. A fast electronic shutter has been developed for a wavefront sensor in an adaptive optics system. An orthogonal transfer CCD has been designed to compensate for the image motion relative to the CCD focal plane. Also, an antiblooming drain process has been developed so bright sources do not...


    African Journals Online (AJOL)


    Jan 18, 2008 ... 3. Data Processing. The microcontroller, the CCD sensor, the stepper motor and the rest of the system are interfaced to the PC where data processing and overall control are done. A software program in. QUICKBASIC is used to process the pixels. First the 1024 pixels of an image line are received from the.

  10. Storage and compression design of high speed CCD (United States)

    Cai, Xichang; Zhai, LinPei


    In current field of CCD measurement, large area and high resolution CCD is used to obtain big measurement image, so that, speed and capacity of CCD requires high performance of later storage and process system. The paper discusses how to use SCSI hard disk to construct storage system and use DSPs and FPGA to realize image compression. As for storage subsystem, Because CCD is divided into multiplex output, SCSI array is used in RAID0 way. The storage system is com posed of high speed buffer, DM A controller, control M CU, SCSI protocol controller and SCSI hard disk. As for compression subsystem, according to requirement of communication and monitor system, the output is fixed resolution image and analog PA L signal. The compression means is JPEG 2000 standard, in which, 9/7 wavelets in lifting format is used. 2 DSPs and FPGA are used to com pose parallel compression system. The system is com posed of FPGA pre-processing module, DSP compression module, video decoder module, data buffer module and communication module. Firstly, discrete wavelet transform and quantization is realized in FPGA. Secondly, entropy coding and stream adaption is realized in DSPs. Last, analog PA L signal is output by Video decoder. Data buffer is realized in synchronous dual-port RAM and state of subsystem is transfer to controller. Through subjective and objective evaluation, the storage and compression system satisfies the requirement of system.

  11. Diagnostics of the CCD using the mesh experiment

    CERN Document Server

    Tsunemi, H; Mori, K; Yoshita, K; Miyata, E


    We present here the results of a mesh experiment with which we can measure the shape of a charge cloud generated by the photoabsorption of X-rays inside a charge-coupled device (CCD). The mesh used is made of gold of 13-mu m thickness, and has many holes of 1.4 mu m diameter spaced 48 mu m apart. The CCD used has 12 mu m square pixels. A new criterion with which we can determine the precise alignment in the experiment is introduced to eliminate uncertainties. We measured the charge cloud size at three X-ray energies: Al-K (1.5 keV), Mo-L (2.3 keV) and Ti-K (4.5 keV). The shapes can be well represented not by a point-symmetric Gaussian function, but by an axial symmetric Gaussian function with sigma of 0.7-1.5 mu m. The charge cloud size depends weakly on the mean absorption length in silicon. We find that the charge cloud size can be well explained by a simple model inside the CCD. We discuss that the knowledge of the charge cloud size will enable us to improve the position resolution of the CCD.

  12. A luminescence imaging system based on a CCD camera

    DEFF Research Database (Denmark)

    Duller, G.A.T.; Bøtter-Jensen, L.; Markey, B.G.


    described here has a maximum spatial resolution of 17 mu m; though this may be varied under software control to alter the signal-to-noise ratio. The camera has been mounted on a Riso automated TL/OSL reader, and both the reader and the CCD are under computer control. In the near u.v and blue part...

  13. Finding Exoplanets Using Point Spread Function Photometry on Kepler Data (United States)

    Amaro, Rachael Christina; Scolnic, Daniel; Montet, Ben


    The Kepler Mission has been able to identify over 5,000 exoplanet candidates using mostly aperture photometry. Despite the impressive number of discoveries, a large portion of Kepler’s data set is neglected due to limitations using aperture photometry on faint sources in crowded fields. We present an alternate method that overcomes those restrictions — Point Spread Function (PSF) photometry. This powerful tool, which is already used in supernova astronomy, was used for the first time on Kepler Full Frame Images, rather than just looking at the standard light curves. We present light curves for stars in our data set and demonstrate that PSF photometry can at least get down to the same photometric precision as aperture photometry. As a check for the robustness of this method, we change small variables (stamp size, interpolation amount, and noise correction) and show that the PSF light curves maintain the same repeatability across all combinations for one of our models. We also present our progress in the next steps of this project, including the creation of a PSF model from the data itself and applying the model across the entire data set at once.

  14. ViFiLite Project (United States)

    National Aeronautics and Space Administration — ViFiLite is a wireless infrastructure that utilizes the advantages of a V-band technology in supporting data gathering for structural health monitoring as well as...

  15. Precision Photometry and Astrometry from Pan-STARRS (United States)

    Magnier, Eugene A.; Pan-STARRS Team


    The Pan-STARRS 3pi Survey has been calibrated with excellent precision for both astrometry and photometry. The Pan-STARRS Data Release 1, opened to the public on 2016 Dec 16, provides photometry in 5 well-calibrated, well-defined bandpasses (grizy) astrometrically registered to the Gaia frame. Comparisons with other surveys illustrate the high quality of the calibration and provide tests of remaining systematic errors in both Pan-STARRS and those external surveys. With photometry and astrometry of roughly 3 billion astronomical objects, the Pan-STARRS DR1 has substantial overlap with Gaia, SDSS, 2MASS and other surveys. I will discuss the astrometric tie between Pan-STARRS DR1 and Gaia and show comparisons between Pan-STARRS and other large-scale surveys.

  16. Skal vi have flere krondyr?

    DEFF Research Database (Denmark)

    Pedersen, Jens Christian


    Vi kunne have væsentligt flere krondyr i den danske natur end vi har i øjeblikket. Den primære årsag er jagt. Det viser en ny undersøgelse fra Danmarks Miljøundersøgelser ved Aarhus Universitet. Bestanden af krondyr er ganske vist steget meget siden 1970, men der er både plads og føde til mange...

  17. Design of a novel spectrophotometer for water quality monitor based on holography concave grating and CCD (United States)

    Ren, Zhong; Liu, Guodong; Zeng, Lvming; Huang, Zhen


    With the rapid development of the society and living standard, the water resources have been polluted more and more seriously, which is threatening the health of people and producing of the industry and agriculture. To protect the sustainable water resource, the monitoring of the water quality became an urgent task. There are some methods used to monitor the water quality, including the liquid chromatograph(LC), electrolysis method, electrochemical method, colorimetry method, atomic absorption spectrometric method, etc. But some drawbacks are existed in these methods. So, a fluorescence spectrophotometry method is adopted into this paper. And a novel water quality monitor(WQM) is designed. Meanwhile, in order to improve the spectral resolution and prevision, an improved spectrophotometer(SPM) based on holography concave (HC)grating is designed. In addition, the linear CCD with combined data acquisition (DAQ) card is used as the spectral detection system and virtual instrument(VI) technology based on LabVIEW is used to control the spectral acquisition and analysis. Experimental results show that the performances of the novel SPM for WQM are improved, its resolution can reach 2nm, the stray-light is less and the checking prevision of this WQM is higher than others. Therefore, the novel SPM for WQM has the potential value in the water quality monitoring and biochemical application.

  18. The spotted contact binary SS ARIETIS - Spectroscopy and infrared photometry (United States)

    Rainger, P. P.; Bell, S. A.; Hilditch, R. W.


    The first infrared photometry for the W-UMa system SS Ari is presented. An analysis based on medium-resolution spectroscopy presented here shows that SS Ari is a W-type system with a mass ratio of 0.33. It seems certain that the asymmetry in the published light curves and those obtained for this study can be explained by the effect of spots on one or possibly both components of the system. The precise location, size and temperature of these spots require the use of Doppler Imaging techniques in conjunction with high-quality multiband photometry.

  19. Gold detector: modular CCD area detector for macromolecular crystallography (United States)

    Naday, Istvan; Ross, Stephan W.; Kanyo, Miklos; Westbrook, Mary L.; Westbrook, Edwin M.; Phillips, Walter C.; Stanton, Martin J.; O'Mara, Daniel M.


    We have designed, fabricated, and tested a modular CCD area detector system for macromolecular crystallography at synchrotron x-ray sources, code-named the `gold' detector system. The sensitive area of the detector is 150 mm X 150 mm, with 3,072 X 3,072 pixel sampling, resulting in roughly a 50 micrometers pixel raster. The x-ray image formed on the face of the detector is converted to visible light by a thin phosphor layer. This image is transferred optically to nine CCD sensors by nine square fiberoptic tapers (one for each CCD), arranged in a 3 X 3 array. Each taper demagnifies the image by a factor of approximately 2. Each CCD has a 1,024 X 1,024 pixel raster and is read out through two independent data channels. After each x-ray exposure period the x-ray shutter is closed and the electronic image is digitized (16-bit) and read out in 1.8s. Alteratively, the image may be binned 2 X 2 during readout, resulting in a 1,536 X 1,536 raster of 100 micrometers pixels; this image can be read out in 0.4s. The CCD sensors are operated at -40 degree(s)C to reduce electronic noise. The detector is operated under full computer control: all operational parameters (readout rates, CCD temperature, etc.) can be adjusted from the console. The image data (18 MByte/image) are transferred via a fast VME system to a control processor and ultimately to disk storage. During April 1994 we carried out a complete set of measurements at the Stanford Synchrotron Radiation Laboratory (SSRL) for a full characterization of the gold detector. Characterization includes quantitative evaluation of the instrument's conversion gain (signal level/x-ray photon); detective quantum efficiency (DQE); point-spread function; sensitivity as a function of x-ray energy; geometrical distortion of images; spatial uniformity; read noise; and dark image and dark image noise. Characterization parameters derived from these measurements show that this detector will be extraordinarily valuable for macromolecular

  20. VizieR Online Data Catalog: Photometry and spectroscopy of EPIC 201702477 (Bayliss+, 2017) (United States)

    Bayliss, D.; Hojjatpanah, S.; Santerne, A.; Dragomir, D.; Zhou, G.; Shporer, A.; Colon, K. D.; Almenara, J.; Armstrong, D. J.; Barrado, D.; Barros, S. C. C.; Bento, J.; Boisse, I.; Bouchy, F.; Brown, D. J. A.; Brown, T.; Cameron, A.; Cochran, W. D.; Demangeon, O.; Deleuil, M.; Diaz, R. F.; Fulton, B.; Horne, K.; Hebrard, G.; Lillo-Box, J.; Lovis, C.; Mawet, D.; Ngo, H.; Osborn, H.; Palle, E.; Petigura, E.; Pollacco, D.; Santos, N.; Sefako, R.; Siverd, R.; Sousa, S. G.; Tsantaki, M.


    The Las Cumbres Observatory Global Telescope (LCOGT) is a network of fully automated telescopes. Currently there are 10 LCOGT 1m telescopes operating as part of this network, eight of which are in the southern hemisphere: three at the Cerro Tololo Inter-American Observatory (CTIO) in Chile, three at the South African Astronomical Observatory (SAAO) in South Africa, and two at Siding Spring Observatory (SSO) in Australia. Each telescope is equipped with an imaging camera; either a "Sinistro" or an SBIG STX-16803. The Sinistro is LCOGT's custom built imaging camera that features a back-illuminated 4K*4K Fairchild Imaging CCD with 15μm pixels (CCD486 BI). With a plate scale of 0.387''/pixel, the Sinistro cameras deliver a FOV of 26.6'*26.6', which is important for monitoring a sufficient number of reference stars for high-precision differential photometry. The cameras are read out by four amplifiers with 1*1 binning, with a readout time of ~45s. The SBIG STX-16803 cameras are commercial CCD cameras which feature a frontside-illuminated 4K*4K CCD with 9μm pixels-giving a field of view of 15.8'*15.8'. These cameras are typically read out in 2*2 binning mode, which results in a read-out time of 12s. The Transiting Exoplanet CHaracterisation (TECH; project uses the 1m telescopes in the LCOGT network to photometrically characterize transiting planets and transiting planet candidates. The first transit event for EPIC201702477b monitored by the TECH project was on 2015 March 15 from CTIO. We observed the target from 01:00 UT to 08:13 UT using a Sinistro in the r-band. The exposure times were 240s, the observing conditions were photometric, and the airmass ranged from 2.3 to 1.2. We detected a full transit of EPIC 201702477b with a depth and duration consistent with that seen in the K2 data. The next transit event occurred 41 days later on 2015 April 28, and was observable from SAAO. EPIC201702477 was monitored between 17:00 UT

  1. The interaction of DNA gyrase with the bacterial toxin CcdB

    DEFF Research Database (Denmark)

    Kampranis, S C; Howells, A J; Maxwell, A


    CcdB is a bacterial toxin that targets DNA gyrase. Analysis of the interaction of CcdB with gyrase reveals two distinct complexes. An initial complex (alpha) is formed by direct interaction between GyrA and CcdB; this complex can be detected by affinity column and gel-shift analysis, and has...

  2. Galileo Photometry of Asteroid 951 Gaspra (United States)

    Helfenstein, P.; Veverka, J.; Thomas, P.C.; Simonelli, D.P.; Lee, P.; Klaasen, K.; Johnson, T.V.; Breneman, H.; Head, J.W.; Murchie, S.; Fanale, F.; Robinson, M.; Clark, B.; Granahan, J.; Garbeil, H.; McEwen, A.S.; Kirk, R.L.; Davies, M.; Neukum, G.; Mottola, S.; Wagner, R.; Belton, M.; Chapman, C.; Pilcher, C.


    Galileo images of Gaspra make it possible for the first time to determine a main-belt asteroid's photometric properties accurately by providing surface-resolved coverage over a wide range of incidence and emission angles and by extending the phase angle coverage to phases not observable from Earth. We combine Earth-based telescopic photometry over phase angles 2?? ??? ?? ??? 25?? with Galileo whole-disk and disk-resolved data at 33?? ??? ?? ??? 51?? to derive average global photometric properties in terms of Hapke's photometric model. The microscopic texture and particle phase-function behavior of Gaspra's surface are remarkably like those of other airless rocky bodies such as the Moon. The macroscopic surface roughness parameter, ??̄ = 29??, is slightly larger than that reported for typical lunar materials. The particle single scattering albedo, ??́0 = 0.36 ?? 0.07, is significantly larger than for lunar materials, and the opposition surge amplitude, B0 = 1.63 ?? 0.07, is correspondingly smaller. We determine a visual geometric albedo pv = 0.22 ?? 0.06 for Gaspra, in close agreement with pv = 0.22 ?? 0.03 estimated from Earth-based observations. Gaspra's phase integral is 0.47, and the bolometric Bond albedo is estimated to be 0.12 ?? 0.03. An albedo map derived by correcting Galileo images with our average global photometric function reveals subdued albedo contrasts of ??10% or less over Gaspra's northern hemisphere. Several independent classification algorithms confirm the subtle spectral heterogeneity reported earlier (S. Mottola, M. DiMartino, M. Gonano-Beurer, H. Hoffman, and G. Neukum, 1993, Asteroids, Comets, Meteors, pp. 421-424; M. J. S. Belton et al., 1992, Science 257, 1647-1652). Whole-disk colors (0.41 ??? ?? ??? 0.99 ??m) vary systematically with longitude by about ??5%, but color differences as large as 30% occur locally. Colors vary continuously between end-member materials whose areal distribution correlates with regional topography. Infrared

  3. Optimization of polarimetry sensitivity for X-ray CCD

    Energy Technology Data Exchange (ETDEWEB)

    Hayashida, K. E-mail:; Tanaka, S.; Tsunemi, H.; Hashimoto, Y.; Ohtani, M


    X-ray polarimetry with CCD has been performed using a polarized X-ray beam from an electron impact X-ray source. The standard data reduction method employing double-pixel events yields the modulation factor M of 0.14 at 27 keV and 0.24 at 43 keV for the 12 {mu}m pixel size CCD chip. We develop a new data reduction method, in which multi-pixel events are employed, and which approximates the charge spread as an oval shape. We optimize the reduction parameters, so that we improve the P{sub min} (minimum detectable polarization degree) by factor of three from the value obtained through the usual double-pixel event method.

  4. Optimization of polarimetry sensitivity for X-ray CCD

    CERN Document Server

    Hayashida, K; Tsunemi, H; Hashimoto, Y; Ohtani, M


    X-ray polarimetry with CCD has been performed using a polarized X-ray beam from an electron impact X-ray source. The standard data reduction method employing double-pixel events yields the modulation factor M of 0.14 at 27 keV and 0.24 at 43 keV for the 12 mu m pixel size CCD chip. We develop a new data reduction method, in which multi-pixel events are employed, and which approximates the charge spread as an oval shape. We optimize the reduction parameters, so that we improve the P sub m sub i sub n (minimum detectable polarization degree) by factor of three from the value obtained through the usual double-pixel event method.

  5. Stroboscope Based Synchronization of Full Frame CCD Sensors

    Directory of Open Access Journals (Sweden)

    Liang Shen


    Full Text Available The key obstacle to the use of consumer cameras in computer vision and computer graphics applications is the lack of synchronization hardware. We present a stroboscope based synchronization approach for the charge-coupled device (CCD consumer cameras. The synchronization is realized by first aligning the frames from different video sequences based on the smear dots of the stroboscope, and then matching the sequences using a hidden Markov model. Compared with current synchronized capture equipment, the proposed approach greatly reduces the cost by using inexpensive CCD cameras and one stroboscope. The results show that our method could reach a high accuracy much better than the frame-level synchronization of traditional software methods.

  6. PSF far wings and ``red halo" in the photometry of galaxies. One more source of errors (United States)

    Michard, R.


    PSF far wings have been measured in UBVRi at the 120 cm Newtonian telescope of Observatoire de Haute Provence, during 3 observing runs in 2000-1. The choice of appropriate star fields allowed us to extend the measurements up to a radius of nearly 3 arcmin, and down to a level of about 0.5*E-6 of the central peak. It was found that these wings, farther than a radius of 15 arcsec, do not change with atmospheric seeing, but are dependent on the spectral passband and the time elapsed since the coating of the mirrors. The most prominent spectral effect is the ``red halo" occurring with thinned CCDs, but PSF wings in U, B, and R may also stand above the V light wings. All PSF wings were greatly reinforced after 10 months of mirror ageing. The consequences of the far PSF wings for galaxy surface photometry and colorimetry have been studied by convolution of models with the measured PSF. Gray models of E-type objects acquire spurious colour gradients, large enough in V-i to reverse the classically measured ones, and sufficient in U-B or U-V to significantly bias the results. The colours along the major and minor axis are unequally affected for flattened objects. Experiments with a model of the lenticular NGC 3115 show that spurious disk colours may also be introduced. It has been verified that the effects of the ``red halo" on V-i colour gradients may be corrected by convolving the frame i with the V PSF and conversely, before measuring the colour distribution. The same is true for the lesser effects in other colours. These ``corrections" are made at the expense of resolution and cause further uncertainties in the results. Based on observations collected at the Observatoire de Haute-Provence.

  7. Series of CCD cameras for low-light-level applications (United States)

    Peri, Michal L.; Weaver, Daniel W.; Ambrose, Tom P.; Hirpara, Dan; Gallagher, Susan; Hall, Andrew M.; Bone, Gregg


    We describe a series of five CCD cameras designed by Gordian for low light-level applications. The first device is a low-cost non-imaging astronomical autoguiding tracker based on the Texas Instruments TC255 CCD chip and an MC6811 microcontroller. Mounting off-axis, it provides standardized tracking-motor signals for any telescope with a dual-axis drive corrector, automatically compensating for the mechanical peculiarities of the drive, set- up factors, and pointing errors. The tracker can guide to +/- 1 arcsec on an 8th magnitude star when used with an 8' aperture, f/10 telescope. The basic autoguider design has been extended to produce self-contained 8-bit and 16-bit imaging cameras with autoguiding functionality. Images are buffered in PSRAM, then relayed to a host PC via an RS-232 serial connection. The addition of regulated thermoelectric cooling reduces CCD thermal noise and alleviates dark current saturation. Gordian has also designed two high-resolution cameras based on the Kodak KAF-0400 and KAF-1600 CCDs. The cameras produce 16-bit images with 768 X 512 pixels or 1536 X 1024 pixels, respectively. Pixel size is 9 micrometers square. The camera head contains the CCD, thermoelectric cooling mechanism, analog electronics, and a custom-designed electromechanical shutter based on FlexinolTM actuator wire. A separate base unit houses a Motorola 68306 microprocessor and associated electronics for telescope control and on-board image processing. A stepper-motor based filter wheel can be attached directly to the camera head. The camera communicates with a personal computer via SCSI or serial connection. Software for the host PC provides additional control options, data storage, and image processing capability.

  8. Design, development, and performance of the STEREO SECCHI CCD cameras (United States)

    Waltham, Nick; Eyles, Chris


    We report the design, development and performance of the SECCHI (Sun Earth Connection Coronal and Heliospheric Investigation) CCD camera electronics on NASA's Solar Terrestrial Relations Observatory (STEREO). STEREO consists of two nearly identical space-based observatories; one ahead of Earth in its orbit, the other trailing behind to provide the first-ever stereoscopic (3D) measurements to study the Sun and the nature of its coronal mass ejections. The SECCHI instrument suite consists of five telescopes that will observe the solar corona, and inner heliosphere all the way from the surface of the Sun to the orbit of the Earth, and beyond. Each telescope contains a large-format science-grade CCD; two within the Heliospheric Imager (HI) instrument, and three in a separate instrument package (SCIP) consisting of two coronagraphs and an EUV imager. The CCDs are operated from two Camera Electronics Boxes. Constraints on the size, mass, and power available for the camera electronics required the development of a miniaturised solution employing digital and mixed-signal ASICs, FPGAs, and compact surface-mount construction. Operating more than one CCD from a single box also provides economy on the number of DC-DC converters and interface electronics required. We describe the requirements for the overall design and implementation, and in particular the design and performance of the camera's space-saving mixed-signal CCD video processing ASIC. The performance of the camera is reviewed together with sample images obtained since the STEREO mission was successfully launched on October 25 2006 from Cape Canaveral.

  9. CCD readout of GEM-based neutron detectors

    CERN Document Server

    Fraga, F A F; Fetal, S T G; Fraga, M; Guérard, B; Manzini, G; Margato, L M S; Oed, A; Policarpo, Armando; Vuure, T V


    We report on the optical readout of the gas electron multiplier (GEM) operated with a gaseous mixture suitable for the detection of thermal neutrons: sup 3 He-CF sub 4. A CCD system operating in the 400-1000 nm band was used to collect the light. Spectroscopic data on the visible and NIR scintillation of He-CF sub 4 are presented. Images of the tracks of the proton and triton recorded with a triple GEM detector are also shown.

  10. A CCD Photometric Study of Close Binary V445 Cep

    Directory of Open Access Journals (Sweden)

    Kyu-Dong Oh


    Full Text Available We present new BVR CCD photometric light curves for the close binary star V445 Cep. A new photometric solution and absolute physical dimensions of the system were derived by applying the Wilson-Devinney program to our observed light curves and radial velocity curves published by Pych et al. The evolutional status of V445 Cep was found to coincide with those of the general low mass ratio contact binary systems.

  11. Design of a CCD Camera for Space Surveillance (United States)


    demonstration of the SensorSat satellite to scan the geosynchronous- orbit belt from low Earth orbit . This mission is technology pathfinder follow-on for the...the geo belt from an equatorial orbit . This is done with a novel approach via microsatellite of only 120 Kg. The satellite will scan the belt...electronics design for observing satellites in the geo belt. The paper discusses the design overview, tactics for tuning operation of a CCD, and

  12. Ortho projection and drawing for archeological artifacts using CCD camera (United States)

    Yokoyama, Hiroshi; Chikatsu, Hirofumi; Miyatsuka, Yoshito


    In the compilation of archival records for archeological artifacts, true orthographic drawings of these artifacts have to be drawn by the archeologists themselves or part-timer, expending a great deal of time, labor, and skills. This paper describes the real time orthographic drawing system using a CCD camera. Finally, it demonstrates real time orthographic drawing results for Jomon pottery by using this system instead of the manual method which requires 3-4 hours.

  13. Analysis of Dark Current in BRITE Nanostellite CCD Sensors

    Directory of Open Access Journals (Sweden)

    Adam Popowicz


    Full Text Available The BRightest Target Explorer (BRITE is the pioneering nanosatellite mission dedicated for photometric observations of the brightest stars in the sky. The BRITE charge coupled device (CCD sensors are poorly shielded against extensive flux of energetic particles which constantly induce defects in the silicon lattice. In this paper we investigate the temporal evolution of the generation of the dark current in the BRITE CCDs over almost four years after launch. Utilizing several steps of image processing and employing normalization of the results, it was possible to obtain useful information about the progress of thermal activity in the sensors. The outcomes show a clear and consistent linear increase of induced damage despite the fact that only about 0.14% of CCD pixels were probed. By performing the analysis of temperature dependencies of the dark current, we identified the observed defects as phosphorus-vacancy (PV pairs, which are common in proton irradiated CCD matrices. Moreover, the Meyer-Neldel empirical rule was confirmed in our dark current data, yielding E M N = 24.8 meV for proton-induced PV defects.

  14. A Bridge Deflection Monitoring System Based on CCD

    Directory of Open Access Journals (Sweden)

    Baohua Shan


    Full Text Available For long-term monitoring of the midspan deflection of Songjiazhuang cloverleaf junction on 309 national roads in Zibo city, this paper proposes Zhang’s calibration-based DIC deflection monitoring method. CCD cameras are used to track the change of targets’ position, Zhang’s calibration algorithm is introduced to acquire the intrinsic and extrinsic parameters of CCD cameras, and the DIC method is combined with Zhang’s calibration algorithm to measure bridge deflection. The comparative test between Zhang’s calibration and scale calibration is conducted in lab, and experimental results indicate that the proposed method has higher precision. According to the deflection monitoring scheme, the deflection monitoring software for Songjiazhuang cloverleaf junction is developed by MATLAB, and a 4-channel CCD deflection monitoring system for Songjiazhuang cloverleaf junction is integrated in this paper. This deflection monitoring system includes functions such as image preview, simultaneous collection, camera calibration, deflection display, and data storage. In situ deflection curves show a consistent trend; this suggests that the proposed method is reliable and is suitable for the long-term monitoring of bridge deflection.

  15. Photometry of transients Gaia17dce and Gaia17dcv (United States)

    Simon, A.; Reshetnyk, V.; Sokolov, I.; Godunova, V.


    We report BVR photometry of transients Gaia17dce and Gaia17dcv performed with the 2-m RCC telescope at the Terskol Observatory. The bright blue hostless transient was discovered by Gaia on 2017-11-27 at magnitude G = 16.67.

  16. Taxonomic Classification of Asteroids via Broadband Near-Infrared Photometry

    NARCIS (Netherlands)

    Petersen, Eric; Thomas, C.; Trilling, D.; Emery, J.; Delbo, M.; Mueller, M.; Dave, R.


    For faint asteroids, it is not practical to obtain near-infrared spectra. However, it may be possible to use broadband photometry to infer spectral classifications and study composition. As a test of this, we processed SpeX near-infrared asteroid spectral data to simulate colors that would be

  17. The BVRI photometry of the UZ Equulei system (United States)

    Bahúl, V.; Gajtanska, M.; Hanisko, P.


    There are described and analyzed the results of the observations of the UZ Equulei system in the summer of the year 2016. The BVRI photometry had been used and the relevant light curves had been constructed. The classification of the system as the EB had been confirmed from two subsequent light curves.

  18. Milli-Magnitude Time-Resolved Photometry with BEST

    DEFF Research Database (Denmark)

    Karoff, Christoffer; Rauer, H.; Erikson, E.


    We present a comparative test of different photometry algorithms. The test has been made in order to optimize the number of stars for which light curves with milli-magnitude precision can be achieved in observations made by the Berlin Exoplanet Search Telescope (BEST), a small wide-angle telescop...

  19. Characterization of Transiting Exoplanets by Way of Differential Photometry (United States)

    Cowley, Michael; Hughes, Stephen


    This paper describes a simple activity for plotting and characterizing the light curve from an exoplanet transit event by way of differential photometry analysis. Using free digital imaging software, participants analyse a series of telescope images with the goal of calculating various exoplanet parameters, including size, orbital radius and…

  20. Surface photometry of nearby field galaxies : The data

    NARCIS (Netherlands)

    Jansen, RA; Franx, M; Fabricant, D; Caldwell, N

    We have obtained integrated spectra and multifilter photometry for a representative sample of similar to 200 nearby galaxies. These galaxies span the entire Hubble sequence in morphological type, as well as a wide range of luminosities (M(B) = -14 to -22) and colors (B-R = 0.4-1.8). Here we describe

  1. Research Note - Absolute UBV Photometry at the Zacatecas Observatory (United States)

    Schuster, W. J.; Parrao, L.; Gonazlez-Bedolla, S. F.; Rios-Herrera, M.; Berumen, M. R.


    Atmospheric extinction data, color coefficients, errors of observation and a list of standard and comparison stars are given for UB V photometry at the Astronomical Observatory in Zacatecas. Our observing and reduction procedures are discussed briefly, and our extinction coefficients and observing errors compared with previous values. The uses of these results are mentioned.

  2. C.C.D. Readout Of A Picosecond Streak Camera With An Intensified C.C.D. (United States)

    Lemonier, M.; Richard, J. C.; Cavailler, C.; Mens, A.; Raze, G.


    This paper deals with a digital streak camera readout device. The device consists in a low light level television camera made of a solid state C.C.D. array coupled to an image intensifier associated to a video-digitizer coupled to a micro-computer system. The streak camera images are picked-up as a video signal, digitized and stored. This system allows the fast recording and the automatic processing of the data provided by the streak tube. Starting from the output screen of the streak camera, the constitutive elements are : - A fiber optic taper (A.O. Scientific Instruments) set in contact with the fiber optic output window of the streak tube achieves the image demagnification ; - A double proximity focused image intensifier (RTC - XX1410 SP) achieves the bright-ness amplification without any distortion ; - A second fiber optic taper achieves the dimensional matching between intensifier output and C.C.D. sensitive area ;

  3. Optical and dark characterization of the PLATO CCD at ESA (United States)

    Verhoeve, Peter; Prod'homme, Thibaut; Oosterbroek, Tim; Duvet, Ludovic; Beaufort, Thierry; Blommaert, Sander; Butler, Bart; Heijnen, Jerko; Lemmel, Frederic; van der Luijt, Cornelis; Smit, Hans; Visser, Ivo


    PLATO - PLAnetary Transits and Oscillations of stars - is the third medium-class mission (M3) to be selected in the European Space Agency (ESA) Science and Robotic Exploration Cosmic Vision programme. It is due for launch in 2025 with the main objective to find and study terrestrial planets in the habitable zone around solar-like stars. The payload consists of >20 cameras; with each camera comprising 4 Charge-Coupled Devices (CCDs), a large number of flight model devices procured by ESA shall ultimately be integrated on the spacecraft. The CCD270 - specially designed and manufactured by e2v for the PLATO mission - is a large format (8 cm x 8 cm) back-illuminated device operating at 4 MHz pixel rate and coming in two variants: full frame and frame transfer. In order to de-risk the PLATO CCD procurement and aid the mission definition process, ESA's Payload Technology Validation section is currently validating the PLATO CCD270. This validation consists in demonstrating that the device achieves its specified electrooptical performance in the relevant environment: operated at 4 MHz, at cold and before and after proton irradiation. As part of this validation, CCD270 devices have been characterized in the dark as well as optically with respect to performance parameters directly relevant for the photometric application of the CCDs. Dark tests comprise the measurement of gain sensitivity to bias voltages, charge injection tests, and measurement of hot and variable pixels after irradiation. In addition, the results of measurements of Quantum Efficiency for a range of angles of incidence, intra- pixel response (non-)uniformity, and response to spot illumination, before and after proton irradiation. In particular, the effect of radiation induced degradation of the charge transfer efficiency on the measured charge in a star-like spot has been studied as a function of signal level and of position on the pixel grid, Also, the effect of various levels of background light on the

  4. Estimation of rice phenology date using integrated HJ-1 CCD and Landsat-8 OLI vegetation indices time-series images* (United States)

    Wang, Jing; Huang, Jing-Feng; Wang, Xiu-Zhen; Jin, Meng-Ting; Zhou, Zhen; Guo, Qiao-Ying; Zhao, Zhe-Wen; Huang, Wei-Jiao; Zhang, Yao; Song, Xiao-Dong


    Accurate estimation of rice phenology is of critical importance for agricultural practices and studies. However, the accuracy of phenological parameters extracted by remote sensing data cannot be guaranteed because of the influence of climate, e.g. the monsoon season, and limited available remote sensing data. In this study, we integrate the data of HJ-1 CCD and Landsat-8 operational land imager (OLI) by using the ordinary least-squares (OLS), and construct higher temporal resolution vegetation indices (VIs) time-series data to extract the phenological parameters of single-cropped rice. Two widely used VIs, namely the normalized difference vegetation index (NDVI) and 2-band enhanced vegetation index (EVI2), were adopted to minimize the influence of environmental factors and the intrinsic difference between the two sensors. Savitzky-Golay (S-G) filters were applied to construct continuous VI profiles per pixel. The results showed that, compared with NDVI, EVI2 was more stable and comparable between the two sensors. Compared with the observed phenological data of the single-cropped rice, the integrated VI time-series had a relatively low root mean square error (RMSE), and EVI2 showed higher accuracy compared with NDVI. We also demonstrate the application of phenology extraction of the single-cropped rice in a spatial scale in the study area. While the work is of general value, it can also be extrapolated to other regions where qualified remote sensing data are the bottleneck but where complementary data are occasionally available. PMID:26465131

  5. Estimation of rice phenology date using integrated HJ-1 CCD and Landsat-8 OLI vegetation indices time-series images. (United States)

    Wang, Jing; Huang, Jing-feng; Wang, Xiu-zhen; Jin, Meng-ting; Zhou, Zhen; Guo, Qiao-ying; Zhao, Zhe-wen; Huang, Wei-jiao; Zhang, Yao; Song, Xiao-dong


    Accurate estimation of rice phenology is of critical importance for agricultural practices and studies. However, the accuracy of phenological parameters extracted by remote sensing data cannot be guaranteed because of the influence of climate, e.g. the monsoon season, and limited available remote sensing data. In this study, we integrate the data of HJ-1 CCD and Landsat-8 operational land imager (OLI) by using the ordinary least-squares (OLS), and construct higher temporal resolution vegetation indices (VIs) time-series data to extract the phenological parameters of single-cropped rice. Two widely used VIs, namely the normalized difference vegetation index (NDVI) and 2-band enhanced vegetation index (EVI2), were adopted to minimize the influence of environmental factors and the intrinsic difference between the two sensors. Savitzky-Golay (S-G) filters were applied to construct continuous VI profiles per pixel. The results showed that, compared with NDVI, EVI2 was more stable and comparable between the two sensors. Compared with the observed phenological data of the single-cropped rice, the integrated VI time-series had a relatively low root mean square error (RMSE), and EVI2 showed higher accuracy compared with NDVI. We also demonstrate the application of phenology extraction of the single-cropped rice in a spatial scale in the study area. While the work is of general value, it can also be extrapolated to other regions where qualified remote sensing data are the bottleneck but where complementary data are occasionally available.

  6. VizieR Online Data Catalog: MOST photometry of Proxima (Kipping+, 2017) (United States)

    Kipping, D. M.; Cameron, C.; Hartman, J. D.; Davenport, J. R. A.; Matthews, J. M.; Sasselov, D.; Rowe, J.; Siverd, R. J.; Chen, J.; Sandford, E.; Bakos, G. A.; Jordan, A.; Bayliss, D.; Henning, T.; Mancini, L.; Penev, K.; Csubry, Z.; Bhatti, W.; da Silva Bento, J.; Guenther, D. B.; Kuschnig, R.; Moffat, A. F. J.; Rucinski, S. M.; Weiss, W. W.


    Microwave and Oscillations of STars (MOST) telescope is a 53kg satellite in low Earth orbit with a 15cm aperture visible band camera (35-750nm). MOST observed Proxima Centauri in 2014 May (beginning on HJD(2000) 2456793.18) for about 12.5 days. MOST again observed Proxima Centauri in 2015 May (starting on HJD(2000) 2457148.54), this time for a total of 31 days. Independent of the MOST observations, Proxima Cen was also monitored by the HATSouth ground-based telescope network. The network consists of six wide-field photometric instruments located at three observatories in the Southern Hemisphere (Las Campanas Observatory [LCO] in Chile, the High Energy Stereoscopic System [HESS] site in Namibia, and Siding Spring Observatory [SSO] in Australia), with two instruments per site. Each instrument consists of four 18cm diameter astrographs and associated 4K*4K backside-illuminated CCD cameras and Sloan r-band filters, placed on a common robotic mount. The four astrographs and cameras together cover a 8.2°*8.2° mosaic field of view at a pixel scale of 3.7''/pixel. Observations of a field containing Proxima Cen were collected as part of the general HATSouth transit survey, with a total of 11071 (this number does not count observations that were rejected as not useful for high-precision photometry, or those that produced large-amplitude outliers in the Proxima Cen light curve) composite 3*80s exposures gathered between 2012 June 14 and 2014 September 20. These include 3430 observations made with the HS-2 unit at LCO, 4630 observations made with the HS-4 unit at the HESS site, and 3011 observations made with the HS-6 unit at the SSO site. Due to weather and other factors, the cadence was nonuniform. The median time difference between consecutive observations in the full time series is 368s. (2 data files).


    Energy Technology Data Exchange (ETDEWEB)

    Amigo, P.; Catelan, M.; Zoccali, M. [Pontificia Universidad Católica de Chile, Instituto de Astrofísica, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago (Chile); Stetson, P. B. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Smith, H. A., E-mail:, E-mail:, E-mail:, E-mail:, E-mail: [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)


    We present new BVI photometry of the globular cluster NGC 6981, based mostly on ground-based CCD archival images. We present a new color-magnitude diagram (CMD) that reaches almost four magnitudes below the turn-off level. We performed new derivations of metallicity and morphological parameters of the evolved sequences, in good agreement with the results of previous authors, and obtain a value of [Fe/H] ≅ –1.50 in the new UVES scale. We also identify the cluster's blue straggler population. Comparing the radial distribution of these stars with the red giant branch population, we find that the blue stragglers are more centrally concentrated, as found in previous studies of blue stragglers in globular clusters. Taking advantage of the large field of view covered by our study, we analyzed the surface density profile of the cluster, and find extratidal main sequence stars out to r ≈ 14.'1, or about twice the tidal radius. We speculate that the presence of these stars may be due to tidal disruption in the course of NGC 6981's orbit, in which case tidal tails associated with the cluster may exist. We also take a fresh look at the variable stars in the cluster, recovering all previously known variables, including three SX Phoenicis stars. We also add three previously unknown RR Lyrae (one c-type and two ab-type) to the total census. Finally, comparing our CMD with unpublished data for M3 (NGC 5272), a cluster with a similar metallicity and horizontal branch morphology, we found that both objects are essentially coeval.

  8. Revisiting the photometry of (308635) 2005 YU_{55} in four colors at McDonald Observatory (United States)

    Ries, J.


    We have obtained wide-field CCD images of asteroid (308635) 2005 YU_{55} during November 13-18, 2011, using the McDonald Observatory 0.76-m telescope with a Prime Focus Corrector. The field of view of this instrument is 45' by 45', which allows reliable relative photometry in spite of the substantial sky motion of the object. We planned to take exposures through the B, V, R, and I filters, and spaced the timing to evenly sample the estimated 18-hour rotational period (based on Arecibo radar observations obtained in April 2010). We have also observed Landolt photometric standards on two separate nights under very good sky conditions to calibrate the target either directly or by calibrating the reference stars imaged with the target. We hoped to obtain color indexes and see how the color affects the lightcurve. Unfortunately, due to a glitch of new software installation at that time, the filter entries in the image headers were incorrect. It was easy to correctly identify the actual filters for the Landolt fields, but we had problems separating the V, R, and I images for the actual object. We are using only the images for which the identification is unambiguous, and we have approximately 100 images in R, 80 in V, 40 in B, and 20 in I. Using the phase parameter and the rotational period determined by other studies (Hicks, et al., Warner, et al.), we attempt to reconstruct the lightcurve in V and R and look for possible phase dependence in the (V-R) color index. Although the radar data favors the 19.31-h rotational period (Busch et al.), we will also check whether our data is consistent with the shorter 16.34-h solution. The results will be presented at the meeting.

  9. Protostars and Planets VI (United States)

    Beuther, Henrik; Klessen, Ralf S.; Dullemond, Cornelis P.; Henning, Thomas

    star and planet formation. They are used by students to dive into new topics, and they are much valued by experienced researchers as a comprehensive overview of the field with all its interactions. We hope that you will enjoy reading (and learning from) this book as much as we do. The organization of the Protostars and Planets conference was carried out in close collaboration between the Max Planck Institute for Astronomy and the Center for Astronomy of the University Heidelberg, with generous support from the German Science Foundation. This volume is a product of effort and care by many people. First and foremost, we want to acknowledge the 250 contributing authors, as it is only due to their expertise and knowledge that such a comprehensive review compendium in all its depth and breadth is possible. The Protostars and Planets VI conference and this volume was a major undertaking, with support and contributions by many people and institutions. We like to thank the members of the Scientific Advisory Committee who selected the 38 teams and chapters out of more than 120 submitted proposals. Similarly, we are grateful to the reviewers, who provided valuable input and help to the chapter authors. The book would also not have been possible without the great support of Renée Dotson and other staff from USRA’s Lunar and Planetary Institute, who handled the detailed processing of all manuscripts and the production of the book, and of Allyson Carter and other staff from the University of Arizona Press. We are also grateful to Richard Binzel, the General Editor of the Space Science Series, for his constant support during the long process, from the original concept to this final product. Finally, we would like to express a very special thank you to the entire conference local organizing committee, and in particular, Carmen Cuevas and Natali Jurina, for their great commitment to the project and for a very fruitful and enjoyable collaboration.

  10. VI Tallinna arhitektuuritriennaal / Leonhard Lapin

    Index Scriptorium Estoniae

    Lapin, Leonhard, 1947-


    15.-17. IX Tallinnas Niguliste kirikus toimuval VI Tallinna arhitektuuritriennaalil esinevad inglise arhitektuurikriitik Peter Davey, šveitsi arhitekt Peter Zumthor, soome arhitekt Juha Leviskä, eesti arhitekt Vilen Künnapu, eesti kunstiajaloolane Juhan Maiste jt. Külastatakse KUMU, tutvutab autor Pekka Vapaavuori

  11. (VI) oxide in acetic acid

    African Journals Online (AJOL)

    The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media was studied. The reaction products were analysed using infra red (IR) and gas chromatography coupled with mass (GC/MS) spectroscopy. The major products of the oxidation reaction in acetic acid medium were cyclohexanol, ...

  12. Rotational spectra of vibrationally excited CCH and CCD. (United States)

    Killian, T C; Gottlieb, C A; Thaddeus, P


    The millimeter-wave rotational spectra of the lowest bending and stretching vibrational levels of CCH and CCD were observed in a low pressure discharge through acetylene and helium. The rotational, centrifugal distortion, and fine structure constants were determined for the (02(0)0) and (02(2)0) bending states, the (100) and (001) stretching levels, and the (011) combination level of CCH. The same pure bending and stretching levels, and the (110) combination level were observed in CCD. Apparent anomalies in the spectroscopic constants in the bending states were shown to be due to l-type resonances. Hyperfine constants, which in CCH are sensitive to the degree of admixture of the A 2Pi excited electronic state, were determined in the excited vibrational levels of both isotopic species. Theoretical Fermi contact and dipole-dipole hyperfine constants calculated by Peric et al. [J. Mol. Spectrosc. 150, 70 (1991)] were found to be in excellent agreement with the measured constants. In CCD, new rotational lines tentatively assigned to the (100) level largely on the basis of the observed hyperfine structure support the assignment of the C-H stretching fundamental (nu1) by Stephens et al. [J. Mol. Struct. 190, 41 (1988)]. Rotational lines in the excited vibrational levels of CCH are fairly intense in our discharge source because the vibrational excitation temperatures of the bending vibrational levels and the (110) and (011) combination levels are only about 100 K higher than the gas kinetic temperature, unlike the higher frequency stretching vibrations, where the excitation temperatures are five to ten times higher.

  13. Apical dominance in saffron and the involvement of the branching enzymes CCD7 and CCD8 in the control of bud sprouting (United States)


    Background In saffron (Crocus sativus), new corms develop at the base of every shoot developed from the maternal corm, a globular underground storage stem. Since the degree of bud sprouts influences the number and size of new corms, and strigolactones (SLs) suppress growth of pre-formed axillary bud, it was considered appropriate to investigate SL involvement in physiology and molecular biology in saffron. We focused on two of the genes within the SL pathway, CCD7 and CCD8, encoding carotenoid cleavage enzymes required for the production of SLs. Results The CsCCD7 and CsCCD8 genes are the first ones isolated and characterized from a non-grass monocotyledonous plant. CsCCD7 and CsCCD8 expression showed some overlapping, although they were not identical. CsCCD8 was highly expressed in quiescent axillary buds and decapitation dramatically reduced its expression levels, suggesting its involvement in the suppression of axillary bud outgrowth. Furthermore, in vitro experiments showed also the involvement of auxin, cytokinin and jasmonic acid on the sprouting of axillary buds from corms in which the apical bud was removed. In addition, CsCCD8 expression, but not CsCCD7, was higher in the newly developed vascular tissue of axillary buds compared to the vascular tissue of the apical bud. Conclusions We showed that production and transport of auxin in saffron corms could act synergistically with SLs to arrest the outgrowth of the axillary buds, similar to the control of above-ground shoot branching. In addition, jasmonic acid seems to play a prominent role in bud dormancy in saffron. While cytokinins from roots promote bud outgrowth. In addition the expression results of CsCCD8 suggest that SLs could positively regulate procambial activity and the development of new vascular tissues connecting leaves with the mother corm. PMID:24947472

  14. Accurate wavelength calibration method for compact CCD spectrometer. (United States)

    Sun, Y C; Huang, C; Xia, G; Jin, S Q; Lu, H B


    Wavelength calibration is an important step in charge-coupled device (CCD) spectrometers. In this paper, an accurate calibration method is proposed. A model of a line profile spectrum is built at the beginning, followed by noise reduction, bandwidth correction, and automatic peak-seeking treatment. Experimental tests are conducted on the USB4000 spectrometer with a mercury-argon calibration light source. Compared with the traditional method, the results show that this wavelength calibration procedure obtains higher accuracy and the deviations are within 0.1 nm.

  15. A Lossy Method for Compressing Raw CCD Images


    Watson, Alan M.


    Se presenta un método para comprimir las imágenes en bruto de dispositivos como los CCD. El método es muy sencillo: cuantizaciòn con pérdida y luego compresión sin pérdida con herramientas de uso general como gzip o bzip2. Se convierten los archivos comprimidos a archivos de FITS descomprimiéndolos con gunzip o bunzip2, lo cual es una ventaja importante en la distribución de datos comprimidos. El grado de cuantizaciòn se elige para eliminar los bits de bajo orden, los cuales...

  16. 29 CFR 1926.1126 - Chromium (VI). (United States)


    ... 29 Labor 8 2010-07-01 2010-07-01 false Chromium (VI). 1926.1126 Section 1926.1126 Labor... Chromium (VI). (a) Scope. (1) This standard applies to occupational exposures to chromium (VI) in all forms... objective data demonstrating that a material containing chromium or a specific process, operation, or...

  17. 29 CFR 1915.1026 - Chromium (VI). (United States)


    ... 29 Labor 7 2010-07-01 2010-07-01 false Chromium (VI). 1915.1026 Section 1915.1026 Labor... § 1915.1026 Chromium (VI). (a) Scope. (1) This standard applies to occupational exposures to chromium (VI... cement; or (4) Where the employer has objective data demonstrating that a material containing chromium or...

  18. Absolute stellar photometry on moderate-resolution FPA images (United States)

    Stone, T.C.


    An extensive database of star (and Moon) images has been collected by the ground-based RObotic Lunar Observatory (ROLO) as part of the US Geological Survey program for lunar calibration. The stellar data are used to derive nightly atmospheric corrections for the observations from extinction measurements, and absolute calibration of the ROLO sensors is based on observations of Vega and published reference flux and spectrum data. The ROLO telescopes were designed for imaging the Moon at moderate resolution, thus imposing some limitations for the stellar photometry. Attaining accurate stellar photometry with the ROLO image data has required development of specialized processing techniques. A key consideration is consistency in discriminating the star core signal from the off-axis point spread function. The analysis and processing methods applied to the ROLO stellar image database are described. ?? 2009 BIPM and IOP Publishing Ltd.

  19. Fundamental performance differences of CMOS and CCD imagers: part V (United States)

    Janesick, James R.; Elliott, Tom; Andrews, James; Tower, John; Pinter, Jeff


    Previous papers delivered over the last decade have documented developmental progress made on large pixel scientific CMOS imagers that match or surpass CCD performance. New data and discussions presented in this paper include: 1) a new buried channel CCD fabricated on a CMOS process line, 2) new data products generated by high performance custom scientific CMOS 4T/5T/6T PPD pixel imagers, 3) ultimate CTE and speed limits for large pixel CMOS imagers, 4) fabrication and test results of a flight 4k x 4k CMOS imager for NRL's SoloHi Solar Orbiter Mission, 5) a progress report on ultra large stitched Mk x Nk CMOS imager, 6) data generated by on-chip sub-electron CDS signal chain circuitry used in our imagers, 7) CMOS and CMOSCCD proton and electron radiation damage data for dose levels up to 10 Mrd, 8) discussions and data for a new class of PMOS pixel CMOS imagers and 9) future CMOS development work planned.

  20. CCD Astrometry of Selected Compact Extragalactic Radio Sources (United States)

    Fedorov, P.; Velichko, F.; Filonenko, V.; Myznikov, A.; Sergeev, V.

    The 64 optical positions relative to the Catalog of Astrometric Standards (USNO-A2.0) and 9 optical positions relative to the Extragalactic Reference Link Catalog (de Vegt at al., 2001) had been obtained for the optical counterparts of 50 northern compact extragalactic radio sources (CERS). These positions were determined at the Kharkov Astronomical Observatory with use the CCD-camera ST-6 of the 0.7-m telescope AZT-8. More than 325 CCD-images of field 10.5' × 8' with optical counterparts of selected CERS had been obtained during 1997-2001. Positions of reference stars (from 6 to 12 stars for each CERS) were obtained from USNO-A2.0 catalogue, Extragalactic Reference Link Catalog and Nikolayev AMC catalogue (Pinigin & Shulga, 1999). The mean internal formal errors of the optical positions of these CERS are 100 mas in right ascension and 70 mas in declination. A comparison with VLBI radio positions for these sources is presented. The mean differences between radio and optical positions from our observations are not significantly differing from zero on the 0.05 significance level. The optical data which we obtained is potentially useful to possibly improve the current link of the Hipparcos reference frame to the ICRS. References de Vegt, C., Hindsley, R., Zacharias, N., Winter, L. 2001, AJ, 2815 Pinigin, G.I., Shulga A.V., 1999, Proc. JOURNESS 1999 & IX. Lohrmann-Kolloquium, Dresden (Germany), 64

  1. Precise CCD positions of Phoebe in 2011-2014 (United States)

    Peng, Q. Y.; Wang, N.; Vienne, A.; Zhang, Q. F.; Li, Z.; Meng, X. H.


    346 new CCD observations during the years 2011-2014 have been reduced to derive the precise positions of Phoebe, the ninth satellite of Saturn. The observations were made by the 2.4 m telescope at Yunnan Observatory over nine nights. Due to the use of a focal-reducer on the telescope, its significant geometric distortion is solved for and removed for each CCD field of view. The positions of Phoebe are measured with respect to the stars in UCAC2 catalogue. The theoretical position of Phoebe was retrieved from the Institute de Méchanique Céleste et de Calcul des Éphémérides ephemeris which includes the latest theory PH12 by Desmars et al., while the position of Saturn was obtained from the Jet Propulsion Laboratory ephemeris DE431. Our results show that the mean O-Cs (observed minus computed) are -0.02 and -0.07 arcsec in right ascension and declination, respectively. The dispersions of our observations are estimated at about 0.04 arcsec in each direction.

  2. Tractability gains in symmetry-adapted perturbation theory including coupled double excitations: CCD+ST(CCD) dispersion with natural orbital truncations (United States)

    Parrish, Robert M.; Hohenstein, Edward G.; Sherrill, C. David


    This work focuses on efficient and accurate treatment of the intermolecular dispersion interaction using the CCD+ST(CCD) dispersion approach formulated by Williams et al. [J. Chem. Phys. 103, 4586 (1995)]. We apply natural orbital truncation techniques to the solution of the monomer coupled-cluster double (CCD) equations, yielding substantial accelerations in this computationally demanding portion of the SAPT2+(CCD), SAPT2+(3)(CCD), and SAPT2+3(CCD) analyses. It is shown that the wholly rate-limiting dimer-basis particle-particle ladder term can be computed in a reduced natural virtual space which is essentially the same size as the monomer-basis virtual space, with an error on the order of a few thousandths of 1 kcal mol-1. Coupled with our existing natural orbital techniques for the perturbative triple excitation contributions [E. G. Hohenstein and C. D. Sherrill, J. Chem. Phys. 133, 104107 (2010)], this technique provides speedups of greater than an order of magnitude for the evaluation of the complete SAPT2+3(CCD) decomposition, with a total error of a few hundredths of 1 kcal mol-1. The combined approach yields tractability gains of almost 2× in the system size, allowing for SAPT2+3(CCD)/aug-cc-pVTZ analysis to be performed for systems such as adenine-thymine for the first time. Natural orbital based SAPT2+3(CCD)/aug-cc-pVTZ results are presented for stacked and hydrogen-bonded configurations of uracil dimer and the adenine-thymine dimer.

  3. Hvad bruger vi tiden til?

    DEFF Research Database (Denmark)

    Brichet, Nathalia Sofie; Hastrup, Frida


    I denne artikel kaster vi et antropologisk blik på samtidsarkæologi ved at diskutere måder, hvorpå antropologiske analyser kan adressere tid, fortidige hændelser og historiske processer. Vi argumenterer for, at en radikal nutidsorientering er en afgørende kvalitet ved det antropologiske feltarbej...... komplicerer en ide om fortidige (gamle eller nyere) objekter som nogle, der kan udgraves......., hvis sigte det er løbende at generere sit materiale nu og her med henblik på at skabe nye forståelser, historier og forslag til mangeartede sammenhænge. En implikation af dette er, at uanset hvor ’historisk’ et antropologisk materiale end måtte være, må det altid ses som samtidigt og ufærdigt, hvilket...

  4. An updated catalog of M33 clusters and candidates: $UBVRI$ photometry, and some statistical results


    Ma, Jun


    We present $UBVRI$ photometry for 392 star clusters and candidates in the field of M33, which are selected from the most recent star cluster catalog. In this catalog, the authors listed star clusters' parameters such as cluster positions, magnitudes and colors in the $UBVRIJHK_s$ filters, and so on. However, a large fraction of objects in this catalog do not have previously published photometry. Photometry is performed using archival images from the Local Group Galaxies Survey, which covers 0...

  5. CCD-based optical CT scanning of highly attenuating phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Al-Nowais, Shamsa [Department of Physics, University of Surrey, Guildford (United Kingdom); Doran, Simon J [CRUK Clinical MR Research Group, Institute of Cancer Research, Sutton (United Kingdom)], E-mail:


    The introduction of optical computed tomography (optical-CT) offers economic and easy to use 3-D optical readout for gel dosimeters. However, previous authors have noted some challenges regarding the accuracy of such imaging techniques at high values of optical density. In this paper, we take a closer look at the 'cupping' artefact evident in both light-scattering polymer systems and highly light absorbing phantoms using our CCD-based optical scanner. In addition, a technique is implemented whereby the maximum measurable optical absorbance is extended to correct for any errors that may have occurred in the estimated value of the dark current or ambient light reaching the detector. The results indicate that for absorbance values up to 2.0, the optical scanner results have good accuracy, whereas this is not the case at high absorbance values for reasons yet to be explained.

  6. Contribution of the Chromosomal ccdAB Operon to Bacterial Drug Tolerance. (United States)

    Gupta, Kritika; Tripathi, Arti; Sahu, Alishan; Varadarajan, Raghavan


    One of the first identified and best-studied toxin-antitoxin (TA) systems in Escherichia coli is the F-plasmid-based CcdAB system. This system is involved in plasmid maintenance through postsegregational killing. More recently, ccdAB homologs have been found on the chromosome, including in pathogenic strains of E. coli and other bacteria. However, the functional role of chromosomal ccdAB genes, if any, has remained unclear. We show that both the native ccd operon of the E. coli O157 strain (ccdO157) and the ccd operon from the F plasmid (ccdF), when inserted on the E. coli chromosome, lead to protection from cell death under multiple antibiotic stress conditions through formation of persisters, with the O157 operon showing higher protection. While the plasmid-encoded CcdB toxin is a potent gyrase inhibitor and leads to bacterial cell death even under fully repressed conditions, the chromosomally encoded toxin leads to growth inhibition, except at high expression levels, where some cell death is seen. This was further confirmed by transiently activating the chromosomal ccd operon through overexpression of an active-site inactive mutant of F-plasmid-encoded CcdB. Both the ccdF and ccdO157 operons may share common mechanisms for activation under stress conditions, eventually leading to multidrug-tolerant persister cells. This study clearly demonstrates an important role for chromosomal ccd systems in bacterial persistence.IMPORTANCE A large number of free-living and pathogenic bacteria are known to harbor multiple toxin-antitoxin systems, on plasmids as well as on chromosomes. The F-plasmid CcdAB system has been extensively studied and is known to be involved in plasmid maintenance. However, little is known about the function of its chromosomal counterpart, found in several pathogenic E. coli strains. We show that the native chromosomal ccd operon of the E. coli O157 strain is involved in drug tolerance and confers protection from cell death under multiple antibiotic

  7. Crowded Field Galaxy Photometry: Precision Colors in the CLASH Clusters (United States)

    Connor, Thomas; Donahue, Megan; Kelson, Daniel D.; Moustakas, John; Coe, Dan; Postman, Marc; Bradley, Larry D.; Koekemoer, Anton M.; Melchior, Peter; Umetsu, Keiichi; Voit, G. Mark


    We present a new method for photometering objects in galaxy clusters. We introduce a mode-filtering technique for removing spatially variable backgrounds, improving both detection and photometric accuracy (roughly halving the scatter in the red sequence compared to previous catalogs of the same clusters). This method is based on robustly determining the distribution of background pixel values and should provide comparable improvement in photometric analysis of any crowded fields. We produce new multiwavelength catalogs for the 25 CLASH cluster fields in all 16 bandpasses from the UV through the near-IR, as well as rest-frame magnitudes. A comparison with spectroscopic values from the literature finds a ˜ 30 % decrease in the redshift deviation from previously released CLASH photometry. This improvement in redshift precision, in combination with a detection scheme designed to maximize purity, yields a substantial upgrade in cluster member identification over the previous CLASH galaxy catalog. We construct luminosity functions for each cluster, reliably reaching depths of at least 4.5 mag below M* in every case, and deeper still in several clusters. We measure M* , α, and their redshift evolution, assuming the cluster populations are coeval, and find little to no evolution of α ,-0.9≲ ≲ -0.8, and M* values consistent with passive evolution. We present a catalog of galaxy photometry, photometric and spectroscopic redshifts, and rest-frame photometry for the full fields of view of all 25 CLASH clusters. Not only will our new photometric catalogs enable new studies of the properties of CLASH clusters, but mode-filtering techniques, such as those presented here, should greatly enhance the data quality of future photometric surveys of crowded fields.

  8. Galaxy properties from J-PAS narrow-band photometry (United States)

    Mejía-Narváez, A.; Bruzual, G.; Magris, C. G.; Alcaniz, J. S.; Benítez, N.; Carneiro, S.; Cenarro, A. J.; Cristóbal-Hornillos, D.; Dupke, R.; Ederoclite, A.; Marín-Franch, A.; de Oliveira, C. Mendes; Moles, M.; Sodre, L.; Taylor, K.; Varela, J.; Ramió, H. Vázquez


    We study the consistency of the physical properties of galaxies retrieved from spectral energy distribution (SED) fitting as a function of spectral resolution and signal-to-noise ratio (SNR). Using a selection of physically motivated star formation histories, we set up a control sample of mock galaxy spectra representing observations of the local Universe in high-resolution spectroscopy, and in 56 narrow-band and 5 broad-band photometry. We fit the SEDs at these spectral resolutions and compute their corresponding stellar mass, the mass- and luminosity-weighted age and metallicity, and the dust extinction. We study the biases, correlations and degeneracies affecting the retrieved parameters and explore the role of the spectral resolution and the SNR in regulating these degeneracies. We find that narrow-band photometry and spectroscopy yield similar trends in the physical properties derived, the former being considerably more precise. Using a galaxy sample from the Sloan Digital Sky Survey (SDSS), we compare more realistically the results obtained from high-resolution and narrow-band SEDs (synthesized from the same SDSS spectra) following the same spectral fitting procedures. We use results from the literature as a benchmark to our spectroscopic estimates and show that the prior probability distribution functions, commonly adopted in parametric methods, may introduce biases not accounted for in a Bayesian framework. We conclude that narrow-band photometry yields the same trend in the age-metallicity relation in the literature, provided it is affected by the same biases as spectroscopy, albeit the precision achieved with the latter is generally twice as large as with the narrow-band, at SNR values typical of the different kinds of data.

  9. Substrate promiscuity of RdCCD1, a carotenoid cleavage oxygenase from Rosa damascena. (United States)

    Huang, Fong-Chin; Horváth, Györgyi; Molnár, Péter; Turcsi, Erika; Deli, József; Schrader, Jens; Sandmann, Gerhard; Schmidt, Holger; Schwab, Wilfried


    Several of the key flavor compounds in rose essential oil are C(13)-norisoprenoids, such as beta-damascenone, beta-damascone, and beta-ionone which are derived from carotenoid degradation. To search for genes putatively responsible for the cleavage of carotenoids, cloning of carotenoid cleavage (di-)oxygenase (CCD) genes from Rosa damascena was carried out by a degenerate primer approach and yielded a full-length cDNA (RdCCD1). The RdCCD1 gene was expressed in Escherichia coli and recombinant protein was assayed for its cleavage activity with a multitude of carotenoid substrates. The RdCCD1 protein was able to cleave a variety of carotenoids at the 9-10 and 9'-10' positions to produce a C(14) dialdehyde and two C(13) products, which vary depending on the carotenoid substrates. RdCCD1 could also cleave lycopene at the 5-6 and 5'-6' positions to produce 6-methyl-5-hepten-2-one. Expression of RdCCD1 was studied by real-time PCR in different tissues of rose. The RdCCD1 transcript was present predominantly in rose flower, where high levels of volatile C(13)-norisoprenoids are produced. Thus, the accumulation of C(13)-norisoprenoids in rose flower is correlated to the expression of RdCCD1.

  10. OV Bootis: Forty Nights Of World-Wide Photometry (United States)

    Patterson, Joseph; de Miguel, Enrique; Barret, Douglas; Brincat, Stephen; Boardman, James, Jr.; Buczynski, Denis; Campbell, Tut; Cejudo, David; Cook, Lew; Cook, Michael J.; Collins, Donald; Cooney, Walt; Dubois, Franky; Dvorak, Shawn; Halpern, Jules P.; Kroes, Anthony J.; Lemay, Damien; Licchelli, Domenico; Mankel, Dylan; Marshall, Matt; Novak, Rudolf; Oksanen, Arto; Roberts, George; Seargeant, Jim; Sears, Huei; Silcox, Austin; Slauson, Douglas; Stone, Geoff; Thorstensen, J. R.; Ulowetz, Joe; Vanmunster, Tonny; Wallgren, John; Wood, Matt


    Among the 1000 known cataclysmic variables, only one appears to belong to the "Galactic halo" - the Population II stars. We report round-the-world photometry of this star (OV Boo) during March-April 2017, when it staged its first certified dwarf-nova outburst. The star is remarkable for its short binary period (66 minutes), high proper motion, metal-poor composition, substellar secondary, sharp white-dwarf eclipses, and nonradial pulsations. Something for everybody...... and it even had the good manners to erupt in northern springtime, when it transits near local midnight. Move over, SS Cyg and WZ Sge; there's a new celebrity in town!

  11. The Photometry Pipeline of the Watcher Robotic Telescope

    Directory of Open Access Journals (Sweden)

    A. Ferrero


    Full Text Available The Watcher robotic telescope was developed primarily to perform rapid optical follow-up observations of Gamma-Ray Bursts (GRBs. Secondary scientific goals include blazar monitoring and variable star studies. An automated photometry pipeline to rapidly analyse data from Watcher has been implemented. Details of the procedures to get image zero-point, source instrumental measurement, and limiting magnitude are presented. Sources of uncertainty are assessed and the performance of the pipeline is tested by comparison with a number of catalogue sources.

  12. Optical photometry and spectroscopy of Nova Del 2013 (United States)

    Tomov, T.; Ilkiewicz, K.; Swierczynski, E.; Belcheva, M.; Dimitrov, D.


    We report optical BV photometry and spectroscopy of Nova Del 2013, carried out between August 14.88 UT and August 15.08 UT. Using a 60 cm Cassegrain telescope at the Nicolaus Copernicus University Observatory (Torun, Poland) we estimated the V brightness of the Nova to be 6.31+/-0.02 mag and 6.18+/-0.03 mag on Aug. 14.94 UT and Aug. 15.02 UT respectively. HD 194113 (F2, V=8.00 mag) was used as a comparison star.

  13. Har vi brug for hovedregning?

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye


    Hvor ofte har vi brug for at regne noget i hoved? Har de fleste af os ikke altid et elektronisk hjælpemiddel ved hånden enten som en lille lommeregner eller telefonen? Selvom det umiddelbart kan synes unødvendigt at træne hovedregning, viser det sig, at netop træning af hovedregning støtter...... udvikling af hurtige regnestrategier, hvorfor det faktisk er en god ide at investere tid og energi i at træne netop dette....

  14. System for Digital 1D-Image Processing with 1024 Pixel CCD Sensor

    Directory of Open Access Journals (Sweden)

    J. Misun


    Full Text Available The conception of system for digital 1D-images processing with digital CCD camera is presented. The system is created from these three basic parts: the digital CCD camera with linear image sensor CCD L133C, 8-bit interface and a personal computer. The scanning digital CCD camera generated a video signals, which are processed in the analog signal processor. The output signal is continually converted to 8-bit data words in A/D converter. This data words maybe transfer over a bus driver to the operation memory of personal computer, by setting one of the three work regimes of digital CCD camera. Some application possibilities and basic technical parameters of this system are given.

  15. Study on enhancing dynamic range of CCD imaging based on digital micro-mirror device (United States)

    Zhou, Wang


    DMD used as SLM modulation area array CCD design is proposed in the paper. It can Solve a problem in exposing high-contrast scenes by ordinary CCD camera, with images appearing over-exposure or under exposure, bringing a loss of the details of the photo. The method adoptes a forecast imaging scene, CCD is purposely designed by way of more exposure regions and exposure times. Through modulation function of DMD micro-mirror, CCD is exposed with sub-region and time-sharing, at the same time a purposely designed structure of image data enhances the area CCD dynamic range. Experiments shows: This method not only improves visible quality of an image and clear details in the backlighting or highlight, but also enhances the dynamic range of image data. The high-quality image and high dynamic range data are real-time captured, the "fused" software is no longer required.

  16. High-Voltage Clock Driver for Photon-Counting CCD Characterization (United States)

    Baker, Robert


    A document discusses the CCD97 from e2v technologies as it is being evaluated at Goddard Space Flight Center's Detector Characterization Laboratory (DCL) for possible use in ultra-low background noise space astronomy applications, such as Terrestrial Planet Finder Coronagraph (TPF-C). The CCD97 includes a photoncounting mode where the equivalent output noise is less than one electron. Use of this mode requires a clock signal at a voltage level greater than the level achievable by the existing CCD (charge-coupled-device) electronics. A high-voltage waveform generator has been developed in code 660/601 to support the CCD97 evaluation. The unit generates required clock waveforms at voltage levels from -20 to +50 V. It deals with standard and arbitrary waveforms and supports pixel rates from 50 to 500 kHz. The system is designed to interface with existing Leach CCD electronics.

  17. CHEOPS: a space telescope for ultra-high precision photometry of exoplanet transits (United States)

    Cessa, V.; Beck, T.; Benz, W.; Broeg, C.; Ehrenreich, D.; Fortier, A.; Peter, G.; Magrin, D.; Pagano, I.; Plesseria, J.-Y.; Steller, M.; Szoke, J.; Thomas, N.; Ragazzoni, R.; Wildi, F.


    The CHaracterising ExOPlanet Satellite (CHEOPS) is a joint ESA-Switzerland space mission dedicated to search for exoplanet transits by means of ultra-high precision photometry whose launch readiness is expected end 2017. The CHEOPS instrument will be the first space telescope dedicated to search for transits on bright stars already known to host planets. By being able to point at nearly any location on the sky, it will provide the unique capability of determining accurate radii for a subset of those planets for which the mass has already been estimated from ground-based spectroscopic surveys. CHEOPS will also provide precision radii for new planets discovered by the next generation ground-based transits surveys (Neptune-size and smaller). The main science goals of the CHEOPS mission will be to study the structure of exoplanets with radii typically ranging from 1 to 6 Earth radii orbiting bright stars. With an accurate knowledge of masses and radii for an unprecedented sample of planets, CHEOPS will set new constraints on the structure and hence on the formation and evolution of planets in this mass range. To reach its goals CHEOPS will measure photometric signals with a precision of 20 ppm in 6 hours of integration time for a 9th magnitude star. This corresponds to a signal to noise of 5 for a transit of an Earth-sized planet orbiting a solar-sized star (0.9 solar radii). This precision will be achieved by using a single frame-transfer backside illuminated CCD detector cool down at 233K and stabilized within {10 mK . The CHEOPS optical design is based on a Ritchey-Chretien style telescope with 300 mm effective aperture diameter, which provides a defocussed image of the target star while minimizing straylight using a dedicated field stop and baffle system. As CHEOPS will be in a LEO orbit, straylight suppression is a key point to allow the observation of faint stars. The telescope will be the only payload on a spacecraft platform providing pointing stability of cost

  18. VizieR Online Data Catalog: New SDSS and Washington photometry in Segue 3 (Hughes+, 2017) (United States)

    Hughes, J.; Lacy, B.; Sakari, C.; Wallerstein, G.; Davis, C. E.; Schiefelbein, S.; Corrin, O.; Joudi, H.; Le, D.; Haynes, R. M.


    We used the Apache Point Observatory (APO) new Astrophysical Research Consortium Telescope Imaging Camera (ARCTIC) imager and the camera it replaced, Seaver Prototype Imaging camera (SPIcam) for our observations with the 3.5m telescope. The ARCTIC camera has a 4096*4096 STA chip giving 7.5'*7.5' as the FOV when the new 5-inch diameter circular filters are used. The older Washington filters are 3''*3'' and vigniette the FOV. SPIcam had a FOV of 4.8'*4.8'. We have several filter wheels that can handle up to ten 3*3 inch square filters (fewer in full-field mode), where binning 1*1 yields 0.11arcseconds/pixel. The fastest readout time in 2*2 binned mode is about 5s. The blue-UV sensitivity of ARCTIC is greater than that of SPIcam, which was a backside-illuminated SITe TK2048E 2048*2048 pixel CCD with 24 micron pixels, which we also binned (2*2), giving a plate scale of 0.28 arcsec per pixel. Where we combined the data sets, we binned ARCTIC 2*2 and slightly degraded its resolution. We found no irreducible color terms between frames taken with both imagers, internally. From 2013 to 2015, we had 11 half-nights total, and 102 frames had seeing better than 2'', many of which were under photometric conditions, and several nights had subarcsecond seeing. Some of the observations were repeated between SPIcam and ARCTIC, which served to test the new imager. We observed Seg 3 in the Washington filters (Canterna 1976AJ.....81..228C) C and T1 and SDSS ugri filters with both SPIcam and ARCTIC. The frames used are listed in Table1, the overlap between this paper and the Vr-data from Fadely et al. 2011 (Cat. J/AJ/142/88) (not the g and r mag values) and Ortolani et al. 2013 (Cat. J/MNRAS/433/1966) is detailed in Table2. Our photometry is presented in Table3 for all 218 objects detected in our field-of-view in CT1ugri-filters, where we required detections in all filters in order to produce spectral energy distributions (SEDs). We include the z-filter from SDSS DR13 and any 2MASS

  19. Catalog based two-color, relative photometry of NEOs at McDonald Observatory (United States)

    Barker, E. S.; Györgyey Ries, J.; Shelus, P. J.; Ricklefs, R. L.


    The McDonald Observatory astrometry group has been involved in Solar System positional observations since the early 1970's. Since 1995, it has evolved to a CCD-based, almost totally automated, astrometry package. We are focusing our observational program on Near Earth Objects (NEOs) as part of NASA's mission to discover and catalogue 90 percent of NEOs with diameters larger than 1 km by 2008. We carry out confirmation observations of newly discovered objects and contribute to orbit improvements of under-observed objects. Understanding the overall hazard that these objects pose to Earth requires their dynamical and physical characterization. We recently adopted the USNO-A2.0 catalogue to improve our astrometric results. The catalog, however, also provides stellar magnitudes in the standard Johnson R and B photometric bands. After completing the night’s observing program, we now regularly provide the IAU with R magnitudes in addition to astrometric positions. Our limiting magnitude in R is near 22 in a 15 minute exposure over a 46 arcmin field on the 0.8m prime focus camera. Typically, we are scheduled for 4 nights each lunation, but our semi-automated, IRAF/ICE based program can be used by other 0.8m users. We are testing procedures that will include B and V exposures as part of our standard confirmation triplet. We have confirmed that switching filters between exposures on standard fields does not compromise the astrometric accurary. Thus, we should be able to provide two color, sequential, relative photometry of any newly discovered asteroid, as part of the confirmation process. The time interval between exposures is less than 20 minutes, short compared to most asteroid rotation times. Consequently, a meaningful color index can be obtained in parallel with the astrometric positions. Although B-R is not the usual color index used in asteroid classification studies, we are testing whether we can use it as a quick diagnostic tool to roughly classify newly

  20. A Search for Transits of Proxima b in MOST Photometry (United States)

    Kipping, David M.


    The recent discovery of a potentially rocky planet in the habitable-zone of our nearest star presents exciting prospects for future detailed characterization of another world. If Proxima b transits its star, the road to characterization would be considerably eased. In 2014 and 2015, we monitored Proxima Centauri with the Canadian space telescope MOST for a total of 43 days. As expected, the star presents considerable photometric variability due to flares, which greatly complicate our analysis. Using Gaussian process regression and Bayesian model selection with informative priors for the time of transit of Proxima b, we do find evidence for a transit of the expected depth. However, relaxing the prior on the transit time to an uninformative one returns a distinct solution highlighting the high false-positive rate induced by flaring. Using ground-based photometry from HATSouth, we show that our candidate transit is unlikely to be genuine although a conclusive answer will likely require infrared photometry, such as that from Spitzer, where flaring should be suppressed.

  1. Orion Project: A Photometry and Spectroscopy Project for Small Observatories (United States)

    Hopkins, Jeffrey L.


    Orion, the hunter, is one of the most famous constellations. Its declination is such that it is visible from most of the civilized world. In addition, most of the stars of Orion are very bright and interesting. Originally this Project was called the Betelgeuse Campaign, but four more stars were added so the name was changed to the Orion Project. The Project now includes Betelgeuse, Rigel and the three stars of Orion's belt, Mintaka, Alnilam and Alnitak. Both photometry and spectroscopy provide data for the Project. The Project has several goals. First is to help beginners with photometry and spectroscopy. The second goal is the actual observations and data. Because these stars are very bright, they are seldom observed in detail. Their brightness also posses a problem for most professional observatories. It is hoped that by having observations over a long time, interesting changes can be seen that will warrant closer investigation. The AAVSO has an excellent archive of photometric data, but is still lacking a means of handling spectroscopic data. As a third goal it is hoped that the procedures refined in this Project for spectroscopic data may help promote a similar system for the AAVSO.

  2. APASS Landolt-Sloan BVgri Photometry of RAVE Stars. I. Data, Effective Temperatures, and Reddenings

    NARCIS (Netherlands)

    Munari, U.; Henden, A.; Frigo, A.; Zwitter, T.; Bienaymé, O.; Bland-Hawthorn, J.; Boeche, C.; Freeman, K. C.; Gibson, B. K.; Gilmore, G.; Grebel, E. K.; Helmi, A.; Kordopatis, G.; Levine, S. E.; Navarro, J. F.; Parker, Q. A.; Reid, W.; Seabroke, G. M.; Siebert, A.; Siviero, A.; Smith, T. C.; Steinmetz, M.; Templeton, M.; Terrell, D.; Welch, D. L.; Williams, M.; Wyse, R. F. G.


    We provide AAVSO Photometric All-Sky Survey (APASS) photometry in the Landolt BV and Sloan g'r'i' bands for all 425,743 stars included in the fourth RAVE Data Release. The internal accuracy of the APASS photometry of RAVE stars, expressed as the error of the mean of data obtained and separately

  3. MC-SPAM: Monte-Carlo Synthetic-Photometry/Atmosphere-Model (United States)

    Espinoza, Néstor; Jordán, Andrés


    MC-SPAM (Monte-Carlo Synthetic-Photometry/Atmosphere-Model) generates limb-darkening coefficients from models that are comparable to transit photometry; it extends the original SPAM algorithm by Howarth (2011) by taking in consideration the uncertainty on the stellar and transit parameters of the system under analysis.

  4. Design of a novel laser-induced fluorescence spectrophotometer for water quality monitor based on virtual instrument and linear CCD (United States)

    Ren, Zhong; Huang, Shuanggen; Liu, Guodong; Huang, Zhen; Zeng, Lvming


    Since the water resource is being seriously polluted with the development of the human society, the monitoring of the available water resource is an impending task. The concentration of the dissolved organic matter, oxygen and inorganic salt in water can be checked by means of some methods, e.g. electrolysis, electrochemical method, colorimetry. But because some drawbacks are existed in these methods, the laser-induced fluorescence (LIF) spectrophotometry method is adopted into this paper. And a novel LIF spectrophotometer for water quality monitor (WQM) is designed. In this WQM, the 3rd harmonic of the Q switched Nd:YAG laser is used as the induced fluorescence light-source. And for the splitting-light system of the spectrophotometer for WQM, in order to improve the resolution and light-passing efficiency, a novel volume holography transmissive(VHT) grating is used as the diffraction grating instead of the plane or holography grating. Meanwhile, the linear CCD with combined data acquisition (DAQ) card is used as the fluorescence spectral detection system and virtual instrument (VI) technology based on LabVIEW is used to control the spectral acquisition and analysis. Experimental results show that the spatial resolution of the novel spectrophotometer for WQM is improved, its resolution can reach 2nm. And the checking accuracy of this WQM is higher than others. Therefore, the novel LIF spectrophotometer for WQM has the potential value in the water quality monitoring and biochemical application.

  5. Vi tror ikke noget, vi undersøger det

    DEFF Research Database (Denmark)

    Hansen, Gitte Riis; Winther Johannsen, Inger


    I diskussionerne om, hvad der kan betegnes som god viden i forhold til udvikling af pædagogisk ud-vikling og kvalitet, er yderpunkterne kridtet op. Begreber som ”evidensbaseret” og ”datainformeret” synes at udfordre det pædagogiske felts egen forståelse af faglighed og pædagogisk kvalitet. I proj...... tager afsæt i det konkrete projekt og samarbejdet med døgntilbuddene. Vi viser, at arbejdet med datainformeret metode på denne måde ikke er en udradering af pædagogisk faglighed knyttet til fagprofessionel dømmekraft – snarere tværtimod...

  6. An Ultraviolet-Visible (UV Photometry System Based on the PDMS-based Microfluidic Chip

    Directory of Open Access Journals (Sweden)

    Xiang Changhua


    Full Text Available In order to avoid a problem remains with the low accuracy and poor portability of the photometry system, the system based on the photometry method and microfluidic chip technology was built. As the characteristics of cheap, solid and good transmission, Polydimethylsiloxane (PDMS was chosen as the material of the designed chip in the paper. To the designed UV photometry system, the light-emitting diode with wavelength of 580m is chosen as the light source. The experimental result indicates that there is no significant deviation between the designed UV photometry system and the conventional immuneturbidimetric assay, the correlation coefficient is 0.95 obtained by adopting the linear regression analysis. The linearity of the designed UV photometry system based on the PDMS-based microfluidic chip has increased by 17.3% in comparison with the system based on the silicon-based microfluidic chip.

  7. NIR spectrophotometric system based on a conventional CCD camera (United States)

    Vilaseca, Meritxell; Pujol, Jaume; Arjona, Montserrat


    The near infrared spectral region (NIR) is useful in many applications. These include agriculture, the food and chemical industry, and textile and medical applications. In this region, spectral reflectance measurements are currently made with conventional spectrophotometers. These instruments are expensive since they use a diffraction grating to obtain monochromatic light. In this work, we present a multispectral imaging based technique for obtaining the reflectance spectra of samples in the NIR region (800 - 1000 nm), using a small number of measurements taken through different channels of a conventional CCD camera. We used methods based on the Wiener estimation, non-linear methods and principal component analysis (PCA) to reconstruct the spectral reflectance. We also analyzed, by numerical simulation, the number and shape of the filters that need to be used in order to obtain good spectral reconstructions. We obtained the reflectance spectra of a set of 30 spectral curves using a minimum of 2 and a maximum of 6 filters under the influence of two different halogen lamps with color temperatures Tc1 = 2852K and Tc2 = 3371K. The results obtained show that using between three and five filters with a large spectral bandwidth (FWHM = 60 nm), the reconstructed spectral reflectance of the samples was very similar to that of the original spectrum. The small amount of errors in the spectral reconstruction shows the potential of this method for reconstructing spectral reflectances in the NIR range.

  8. Machine vision: recent advances in CCD video camera technology (United States)

    Easton, Richard A.; Hamilton, Ronald J.


    This paper describes four state-of-the-art digital video cameras, which provide advanced features that benefit computer image enhancement, manipulation, and analysis. These cameras were designed to reduce the complexity of imaging systems while increasing the accuracy, dynamic range, and detail enhancement of product inspections. Two cameras utilize progressive scan CCD sensors enabling the capture of high- resolution image of moving objects without the need for strobe lights or mechanical shutters. The second progressive scan camera has an unusually high resolution of 1280 by 1024 and a choice of serial or parallel digital interface for data and control. The other two cameras incorporate digital signal processing (DSP) technology for improved dynamic range, more accurate determination of color, white balance stability, and enhanced contrast of part features against the background. Successful applications and future product development trends are discussed. A brief description of analog and digital image capture devices will address the most common questions regarding interface requirements within a typical machine vision system overview.

  9. Constraints on the Bulk Composition of Uranus from Herschel PACS and ISO LWS Photometry, SOFIA FORCAST Photometry and Spectroscopy, and Ground-Based Photometry of its Thermal Emission (United States)

    Orton, Glenn; Mueller, Thomas; Burgdorf, Martin; Fletcher, Leigh; de Pater, Imke; Atreya, Sushil; Adams, Joseph; Herter, Terry; Keller, Luke; Sidher, Sunil; Sinclair, James; Fujiyoshi, Takuya


    We present thermal infrared observations of the disk of Uranus at 17-200 μm to deduce its global thermal structure and bulk composition. We combine 17-200 μm filtered photometric measurements by the Herschel PACS and ISO LWS instruments and 19-35 μm filtered photometry and spectroscopy by the SOFIA FORCAST instrument, supplemented by 17-25 μm ground-based photometric filtered imaging of Uranus. Previous analysis of infrared spectroscopic measurements of the disk of Uranus made by the Spitzer IRS instrument yielded a model for the disk-averaged temperature profile and stratospheric composition (Orton et al. 2014a Icarus 243,494; 2014b Icarus 243, 471) that were consistent with submillimeter spectroscopy by the Herschel SPIRE instrument (Swinyard et al. 2014, MNRAS 440, 3658). Our motivation to observe the 17-35 μm spectrum was to place more stringent constraints on the global para-H2 / ortho-H2 ratio in the upper troposphere and lower stratosphere than the ISO SWS results of Fouchet et al. (2003, Icarus 161, 127), who examined H2 quadrupole lines. We will discuss the consistency of these observations with a higher para-H2 fraction than implied by local thermal equilibrium, which would resolve a discrepancy between the Spitzer-based model and observations of HD lines by the Herschel PACS experiment (Feuchtgruber et al. 2013 Astron. & Astrophys. 551, A126). Constraints on the global para-H2 fraction allow for more precise analysis of the far-infrared spectrum, which is sensitive to the He:H2 ratio, a quantity that was not constrained by the Spitzer IRS spectra. The derived model, which assumed the ratio derived by the Voyager-2 IRIS/radio-science occultation experiment (Conrath et al. 1987 J. Geophys. Res. 92, 15003), is inconsistent with 70-200 μm PACS photometry (Mueller et al. 2016 Astron. & Astrophys. submittted) and ISO LWS photometric measurements. However, the model can be made consistent with the observations if the fraction of He relative to H2 were

  10. RCT photometry of the Hubble Classical Cepheid V19 in M33: Evidence for the Cessation of Pulsations - A Case of Stellar Evolution in Real Time (United States)

    Engle, Scott G.; Guinan, Edward F.; Macri, Lucas; Pellerin, Ann


    possible reasons for its apparent fast evolutionary changes. In this study we have combined the recent RCT CCD photometry with unpublished photometry secured a few years ago with the WIYN 3.5-m telescope as well as using the available photometry back to Hubble's original observations carried out during the mid-1920s. These data have been subjected to various period search routines to identify possible periods. We also discuss some possible scenarios to explain the strange behavior of the star. We gratefully acknowledge support from a NASA/HST grant and NSF/RUI grant AST-1009903. The RCT is operated by the RCT Consortium - a group of universities and research institutions who have assumed control of the 1.3-m (50-inch) telescope on Kitt Peak, Arizona. The Consortium members are Western Kentucky University, the Planetary Science Institute, South Carolina State University, and Villanova University.

  11. CCD TV focal plane guider development and comparison to SIRTF applications (United States)

    Rank, David M.


    It is expected that the SIRTF payload will use a CCD TV focal plane fine guidance sensor to provide acquisition of sources and tracking stability of the telescope. Work has been done to develop CCD TV cameras and guiders at Lick Observatory for several years and have produced state of the art CCD TV systems for internal use. NASA decided to provide additional support so that the limits of this technology could be established and a comparison between SIRTF requirements and practical systems could be put on a more quantitative basis. The results of work carried out at Lick Observatory which was designed to characterize present CCD autoguiding technology and relate it to SIRTF applications is presented. Two different design types of CCD cameras were constructed using virtual phase and burred channel CCD sensors. A simple autoguider was built and used on the KAO, Mt. Lemon and Mt. Hamilton telescopes. A video image processing system was also constructed in order to characterize the performance of the auto guider and CCD cameras.

  12. Mosaic CCD method: A new technique for observing dynamics of cometary magnetospheres (United States)

    Saito, T.; Takeuchi, H.; Kozuba, Y.; Okamura, S.; Konno, I.; Hamabe, M.; Aoki, T.; Minami, S.; Isobe, S.


    On April 29, 1990, the plasma tail of Comet Austin was observed with a CCD camera on the 105-cm Schmidt telescope at the Kiso Observatory of the University of Tokyo. The area of the CCD used in this observation is only about 1 sq cm. When this CCD is used on the 105-cm Schmidt telescope at the Kiso Observatory, the area corresponds to a narrow square view of 12 ft x 12 ft. By comparison with the photograph of Comet Austin taken by Numazawa (personal communication) on the same night, we see that only a small part of the plasma tail can be photographed at one time with the CCD. However, by shifting the view on the CCD after each exposure, we succeeded in imaging the entire length of the cometary magnetosphere of 1.6 x 106 km. This new technique is called 'the mosaic CCD method'. In order to study the dynamics of cometary plasma tails, seven frames of the comet from the head to the tail region were twice imaged with the mosaic CCD method and two sets of images were obtained. Six microstructures, including arcade structures, were identified in both the images. Sketches of the plasma tail including microstructures are included.

  13. Mens vi venter på finansloven ..

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove


    Vi må dog lufte en forsigtig optimisme over, at der kom signaler om opgør med detailstyring og knopskydningen af øremærket forskning.......Vi må dog lufte en forsigtig optimisme over, at der kom signaler om opgør med detailstyring og knopskydningen af øremærket forskning....

  14. Når vi taler om 68

    DEFF Research Database (Denmark)

    Jensen, Henrik; Metz, Georg

    Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi......Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi...


    National Research Council Canada - National Science Library

    Drake, Leigh


    The ViBe District in Virginia Beach is a hub for the local arts community. There is a fenced area in the ViBe District that features a whole row of murals created by professional artists, amateurs, and student groups from all over...

  16. The carotenoid cleavage dioxygenase CCD2 catalysing the synthesis of crocetin in spring crocuses and saffron is a plastidial enzyme. (United States)

    Ahrazem, Oussama; Rubio-Moraga, Angela; Berman, Judit; Capell, Teresa; Christou, Paul; Zhu, Changfu; Gómez-Gómez, Lourdes


    The apocarotenoid crocetin and its glycosylated derivatives, crocins, confer the red colour to saffron. Crocetin biosynthesis in saffron is catalysed by the carotenoid cleavage dioxygenase CCD2 (AIG94929). No homologues have been identified in other plant species due to the very limited presence of crocetin and its derivatives in the plant kingdom. Spring Crocus species with yellow flowers accumulate crocins in the stigma and tepals. Four carotenoid CCDs, namely CaCCD1, CaCCD2 and CaCCD4a/b and CaCCD4c were first cloned and characterized. CaCCD2 was localized in plastids, and a longer CCD2 version, CsCCD2L, was also localized in this compartment. The activity of CaCCD2 was assessed in Escherichia coli and in a stable rice gene function characterization system, demonstrating the production of crocetin in both systems. The expression of all isolated CCDs was evaluated in stigma and tepals at three key developmental stages in relation with apocarotenoid accumulation. CaCCD2 expression parallels crocin accumulation, but C14 apocarotenoids most likely are associated to the CaCCD1 activity in Crocus ancyrensis flowers. The specific CCD2 localization and its membrane interaction will contribute to the development of a better understanding of the mechanism of crocetin biosynthesis and regulation in the chromoplast. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  17. Fibromyalgia in patients with chronic CCD and CMD - A retrospective study of 555 patients. (United States)

    Losert-Bruggner, Brigitte; Hülse, Manfred; Hülse, Roland


    Craniomandibular dysfunction (CMD) and craniocervical dysfunction (CCD) are clearly defined musculoskeletal pain syndromes. Relationships with fibromyalgia syndrome (FMS) have not yet been investigated. The aim of the present study is to establish possible relationships between FMS and CMD/ CCD. In a retrospective study, 555 patients with CCD and CMD were investigated with respect to the diagnostic criteria of FMS. In addition to otolaryngologic and dental examination, an instrumental functional analysis for the diagnosis of CMD/CCD was performed. Three hundred fifty-one (63%) of the 555 patients evaluated met the diagnostic criteria for FMS. Seventy-two percent of the patients had a widespread pain index of at least 7 and a severity scale score of at least 5. Twenty-nine percent had a widespread pain index of 3-6 and a severity scale score of at least 9. Using myocentric bite splint therapy and therapy with oral orthesis in combination with neuromuscular relaxation measures, a good to very good improvement of physical symptoms was seen in 84% of CMD-FMS patients, and an improvement of the symptoms in the jaw was achieved in 77% of cases. The substantial proportion of CMD and CCD patients who meet the criteria for FMS emphasizes the complexity of the two diseases. It must be assumed that FMS is a crucial factor for the formation of CMD and CCD. Conversely, CMD/ CCD could also be responsible for diverse clinical pictures of the FMS. FMS patients with synchronous CCD/CMD benefit from an interdisciplinary CMD/CCD treatment.

  18. Econophys-Kolkata VI Conference

    CERN Document Server

    Chakrabarti, Bikas; Chakraborti, Anirban; Ghosh, Asim


    The primary goal of the book is to present the ideas and research findings of active researchers such as physicists, economists, mathematicians and financial engineers working in the field of “Econophysics,” who have undertaken the task of modeling and analyzing systemic risk, network dynamics and other topics. Of primary interest in these studies is the aspect of systemic risk, which has long been identified as a potential scenario in which financial institutions trigger a dangerous contagion mechanism, spreading from the financial economy to the real economy. This type of risk, long confined to the monetary market, has spread considerably in the recent past, culminating in the subprime crisis of 2008. As such, understanding and controlling systemic risk has become an extremely important societal and economic challenge. The Econophys-Kolkata VI conference proceedings are dedicated to addressing a number of key issues involved. Several leading researchers in these fields report on their recent work and al...

  19. KIC 8462852: Maria Mitchell Observatory Photographic Photometry 1930 to 1985 (United States)

    Castelaz, Michael; Barker, Thurburn


    KIC 8462852 is an F3V star which decreased 20% in visual brightness twice from 5 to 20 days (Boyajian et al., 2016, MNRAS, 457, 3988) in 2011 and again in 2013. New observations show decreases of a few percent in May 2017 (Waagen 2017, AAVSO Alert Notice, 579), and reanalysis of Kepler data shows a variation of 928.25 days and 22 dimming events (Kiefer et al. 2017, accepted). Photometry from the All-Sky Automated Survey for Supernovae and the All-Sky Automated Survey (ASAS) indicate two brightening episodes and a steady decrease in magnitude of 6.3 +/- 1.4 mmag/yr (Simon et al 2017, accepted). Photometric studies from photographic plate collections include a light curve from 1338 Harvard College Observatory plates over the period 1890 to 1989 (Schaefer 2016, ApJ, 822, L34) that indicates KIC 8462852 is dimming 0.164 +/- 0.013 magnitudes per century. Hippke et al. (2016, ApJ, 825, 73) present B and V light curves from photometry from the Sonneberg Observatory photographic plate collection (Brauer and Fuhrmann 1992, Die Sterne, 68, 19) covering the period from 1934 to 1995. The light curve suggests less than 3% or 0.03 magnitude per century decrease in brightness, consistent with the ASAS light curve and Kepler data.Another consistent set of astronomical photographic plates with KIC 8462852 are in the Maria Mitchell Observatory (MMO) collection (Strelnitski 2009 in ASP Conference Series Vol. 410 p. 96). This collection is located in the Astronomical Photographic Data Archive at the Pisgah Astronomical Research Institute. We extracted the photographic magnitudes of KIC 8462852 from 743 plates from 1930 to 1988. We chose 8 nearby comparison stars within one spectral subclass and within 0.05 magnitudes of KIC 8462852, and not identified as variables. The photometry is calibrated to the USNO B filter, closest in bandpass to the emulsion wavelength sensitivity. The light curve of KIC 8462852 suggests a trend of about 0.1 +/- 0.07 magnitudes per century decrease, an

  20. Coordinated Ultraviolet Spectroscopy and Optical Photometry of FK Comae (United States)

    Guinan, Edward F.

    FK Comae (HD 117555) is the prototype of a newly identified class of rapidly rotating, apparently single, cool giants which have strong chromospheric and coronal emission rivalling or surpassing those of the most active RS CVn stars. FK Com is the best studied member of the group. It has spectral type about G2 IIIp, a projected rotational velocity v sin i =120 km/s, and is a low amplitude variable with a 2.4d period. Photometry by Dorren, Guinan and McCook in 1982 shows for the first time that the light curve undergoes rapid changes in amplitude, shape, and phase of light minimum. Such behavior is known for the RS CVn stars, but is generally on longer timescales. Analyses of the 1982 light curves have been carried out and show that the light variations appear to be consistent with subluminous regions ("starspots") on the surface of the rapidly rotating giant. The overall spectroscopic and photometric properties are in general best explained by extreme surface activity induced by rapid rotation. Although rapidly rotating cool giants (v sin i about 20 - 50 km/s) are often members of close binary systems in which tidal effects have produced synchronous rotation, there is no evidence for duplicity in FK Com. This has led Bopp and Stencel to suggest that the FK Com stars are coalesced binaries possibly evolved from W UMa systems. We propose to obtain IUE observations at minimum and maximum of a fully developed photometric wave, when the active regions are facing and directed away from the observer respectively. The light variations will be monitored it Villanova during 1983-1984 to determine the optimum time for scheduling the lUE observations. The previous IUE observations of FK Com were made when no photometry was available or when the light variations were small. We also propose to observe during a flare. The flaring activity will be monitored b), H-alpha photometry. During 1982 at least three long-lived (3-10d) flare events were seen.

  1. Dissimilatory Reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas Isolates

    Energy Technology Data Exchange (ETDEWEB)

    Smith, William Aaron; Apel, William Arnold; Peyton, B. M.; Petersen, J. N.; Sani, R.


    The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain (Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

  2. Dissimilatory reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas isolates. (United States)

    Sani, R K; Peyton, B M; Smith, W A; Apel, W A; Petersen, J N


    The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain ( Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

  3. Genetics Home Reference: collagen VI-related myopathy (United States)

    ... Twitter Home Health Conditions Collagen VI-related myopathy Collagen VI-related myopathy Printable PDF Open All Close ... Javascript to view the expand/collapse boxes. Description Collagen VI-related myopathy is a group of disorders ...

  4. Finite difference simulation of biological chromium (VI) reduction in ...

    African Journals Online (AJOL)

    (VI) concentration profiles inside porous aquifer media columns. The model was thereafter used to calculate Cr(VI) removal rate for a range of Cr(VI) loadings. Internal concentration profiles were modelled against data collected from ...

  5. RI: CCD-FO Assembly for Spectroscopic Characterization of Flame Synthesis Processes (United States)


    involving thermite reactions with nano-Al. Specifically, the CCD-FO component of 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 15-02-2012 13...for nano-energetic applications involving thermite reactions with nano-Al. Specifically, the CCD-FO component of the detector is used as part of a...energetic applications involving thermite reactions with nano-Al. Specifically, the CCD-FO component of the detector is used as part of a laser-based

  6. Asteroid models from photometry and complementary data sources

    Energy Technology Data Exchange (ETDEWEB)

    Kaasalainen, Mikko [Department of Mathematics, Tampere University of Technology (Finland)


    I discuss inversion methods for asteroid shape and spin reconstruction with photometry (lightcurves) and complementary data sources such as adaptive optics or other images, occultation timings, interferometry, and range-Doppler radar data. These are essentially different sampling modes (generalized projections) of plane-of-sky images. An important concept in this approach is the optimal weighting of the various data modes. The maximum compatibility estimate, a multi-modal generalization of the maximum likelihood estimate, can be used for this purpose. I discuss the fundamental properties of lightcurve inversion by examining the two-dimensional case that, though not usable in our three-dimensional world, is simple to analyze, and it shares essentially the same uniqueness and stability properties as the 3-D case. After this, I review the main aspects of 3-D shape representations, lightcurve inversion, and the inclusion of complementary data.

  7. Time Resolved Precision Differential Photometry with OAFA's Double Astrograph (United States)

    González, E. P. A.; Podestá, F.; Podestá, R.; Pacheco, A. M.


    For the last 50 years, the Double Astrograph located at the Carlos U. Cesco station of the Observatorio Astronómico Félix Aguilar (OAFA), San Juan province, Argentina, was used for astrometric observations and research. The main programs involved the study of asteroid positions and proper motions of stars in the Southern hemisphere, being the latter a long time project that is near completion from which the SPM4 catalog is the most recent version (Girard et al. 2011). In this paper, new scientific applications in the field of photometry that can be accomplished with this telescope are presented. These first attempts show the potential of the instrument for such tasks.

  8. Further DA Photometry of I-Bootis Stars (United States)

    Maitzen, H. M.; Pavlovski, K.


    We report on further photometry in order to substantiate the findings of Maitzen and Pavlovski (1989). Although the spectroscopic definition of the λ Bootis stars, a group of chemically peculiar stars (CP) with heavy element underabundances, has not yet been worked out to general satisfaction, the photometric behaviour of a sample of now 45 λ Boo objects in the Δα system (measuring the flux around λ5200) exhibits a clear trend: two thirds show moderate, but significant negative Δα-values. Thus they show an inverse behaviour in comparison with CP2 (magnetic peculiar or Ap-) stars which have positive Δα-excesses and heavy element overabundances. This opens the way to test a theory predicting underabundances as a result of diffusion plus mass loss in chemically stratified atmospheres at the end of the main sequence life time. It is proposed to search for λ Boo stars in open clusters covering a wide range of ages.

  9. Photometry of High-Redshift Gravitationally Lensed Type Ia Supernovae (United States)

    Haynie, Annastasia


    Out of more than 1100 well-identified Type Ia Supernovae, only roughly 10 of them are at z> 1.5. High redshift supernovae are hard to detect but this is made easier by taking advantage of the effects of gravitational lensing, which magnifies objects in the background field of massive galaxy clusters. Supernova Nebra (z= ~1.8), among others, was discovered during observations taken as part of the RELICS survey, which focused on fields of view that experience strong gravitational lensing effects. SN Nebra, which sits behind galaxy cluster Abell 1763, is magnified and therefore appears closer and easier to see than with HST alone. Studying high-redshift supernovae like SN Nebra is an important step towards creating cosmological models that accurately describe the behavior of dark energy in the early Universe. Recent efforts have been focused on improving photometry and the building and fitting of preliminary light curves.

  10. Mapping Milky Way Dust in 3D with Stellar Photometry (United States)

    Green, Gregory Maurice

    I present a three-dimensional map of interstellar dust reddening, covering three-quarters of the sky out to a distance of several kiloparsecs, based on Pan-STARRS 1 and 2MASS photometry. The map reveals a wealth of detailed structure, from filaments to large cloud complexes. The map has a hybrid angular resolution, with most of the map at an angular resolution of 3.4' to 13.7', and a maximum distance resolution of ˜25%. The three-dimensional distribution of dust is determined in a fully probabilistic framework, yielding the uncertainty in the reddening distribution along each line of sight, as well as stellar distances, reddenings and classifications for 800 million stars detected by Pan-STARRS 1. The method developed here compares observed stellar photometry with empirical stellar templates, incorporating prior knowledge about the structure of the Galaxy. I validate the per-star reddening estimates by comparison with reddening estimates for stars with both SDSS photometry and SEGUE spectral classifications, finding per-star agreement to within ˜0.15 mag out to a stellar E( B-V) of 1 mag. I demonstrate the consistency of the resulting reddening estimates with those of two-dimensional emission-based maps of dust reddening. In particular, I find agreement with the Planck tau 353 GHz-based reddening map to within 0.05 mag in E(B-V ) to a depth of 0.5 mag, and explore systematics at reddenings less than E(B-V) ≈ 0.08 mag. I compare the 3D map developed here to two existing three-dimensional dust maps, by Marshall et al. (2006) and Lallement et al. (2013), exploring the strengths and weaknesses of the different 3D mapping methods. The map presented here has better angular resolution than both 3D maps compared, and it has better distance resolution than Marshall et al. (2006) within ˜3 kpc, but shows radial "finger-of-God" features not contained in Lallement et al. (2013). The map can be queried or downloaded at . I expect the three

  11. Characterizing exoplanets atmospheres with space photometry at optical wavelengths

    Directory of Open Access Journals (Sweden)

    Parmentier Vivien


    Full Text Available Space photometry such as performed by Kepler and CoRoT provides exoplanets radius and phase curves with an exquisite precision. The phase curve constrains the longitudinal variation of the albedo and shed light on the horizontal distribution of clouds. The planet radius constraints thermal evolution of the planet, potentially unveiling its atmospheric composition. We present how the atmospheric circulation can affect the cloud distribution of three different planets, HD209458b, Kepler-7b and HD189733b based on three-dimensional models and analytical calculations. Then we use an analytical atmospheric model coupled to a state-of-the-art interior evolution code to study the role of TiO in shaping the thermal evolution and final radius of the planet.

  12. Applied photometry, radiometry, and measurements of optical losses

    CERN Document Server

    Bukshtab, Michael


    Applied Photometry, Radiometry, and Measurements of Optical Losses reviews and analyzes physical concepts of radiation transfer, providing quantitative foundation for the means of measurements of optical losses, which affect propagation and distribution of light waves in various media and in diverse optical systems and components. The comprehensive analysis of advanced methodologies for low-loss detection is outlined in comparison with the classic photometric and radiometric observations, having a broad range of techniques examined and summarized: from interferometric and calorimetric, resonator and polarization, phase-shift and ring-down decay, wavelength and frequency modulation to pulse separation and resonant, acousto-optic and emissive - subsequently compared to direct and balancing methods for studying free-space and polarization optics, fibers and waveguides. The material is focused on applying optical methods and procedures for evaluation of transparent, reflecting, scattering, absorbing, and aggregat...

  13. Discriminação de variedades de citros em imagens CCD/CBERS-2 Discrimination of citrus varieties using CCD/CBERS-2 satellite imagery

    Directory of Open Access Journals (Sweden)

    Ieda Del'Arco Sanches


    Full Text Available O presente trabalho teve o objetivo de avaliar as imagens CCD/CBERS-2 quanto à possibilidade de discriminarem variedades de citros. A área de estudo localiza-se em Itirapina (SP e, para este estudo, foram utilizadas imagens CCD de três datas (30/05/2004, 16/08/2004 e 11/09/2004. Um modelo que integra os elementos componentes da cena citrícola sensoriada é proposto com o objetivo de explicar a variabilidade das respostas das parcelas de citros em imagens orbitais do tipo CCD/CBERS-2. Foram feitas classificações pelos algoritmos Isoseg e Maxver e, de acordo com o índice kappa, concluiu-se que é possível obterem-se exatidões qualificadas como muito boas, sendo que as melhores classificações foram conseguidas com imagens da estação seca.This paper was aimed at evaluating the possibility of discriminating citrus varieties in CCD imageries from CBERS-2 satellite ("China-Brazil Earth Resouces Satellite". The study area is located in Itirapina, São Paulo State. For this study, three CCD images from 2004 were acquired (May 30, August 16, and September 11. In order to acquire a better understanding and for explaining the variability of the spectral behavior of the citrus areas in orbital images (like as the CCD/CBERS-2 images a model that integrates the elements of the citrus scene is proposed and discussed. The images were classified by Isoseg and MaxVer classifiers. According to kappa index, it was possible to obtain classifications qualified as 'very good'. The best results were obtained with the images from the dry season.

  14. Photographic and CCD Sky Patrols with Small Telescopes (United States)

    Kroll, Peter

    Since the twenties of the last century Sonneberg Observatory runs in each clear night a photographic Sky Patrol with a system of small telescopes (55/250 mm) reaching 14m in the blue and 13m in the yellow-red. In addition, a so-called Field Patrol is run with 2 astrographs (400/2000 mm) and a Schmidt camera (500/700/1720 mm) covering 80 selected fields along or near the Milky Way. From these instruments an archive of alomost 300,000 photographic plates arose, documenting the history of the starry night over more than 75 years. Currently much effort is made to take over this photographic sky patrol by a system of electronic detectors. Owing to the fact, that wide-field systems need either large CCDs or arrays of CCDs in order to cover the whole field of view, the technical availability of large detectors was one of the central problems in past. We now invent the use of a PHILIPS 4K×7K chip in wide-field astronomy for Whole-Sky Patrol. Although the chip has a quantum efficiency of only about 30 %, its big size (12μm pixel size) of 48×84 mm offers, for the first time, the replacement of large photographic plates by a single CCD chip. We report our first experiences with this chip when using it with a super wide-angle objective for whole-sky imaging each minute down to ca. 10m for investigating different targets (variable stars, meteors, GRB counterparts, etc.) and first trial to use the large-size chip with other small telescopes (400 to 600 mm diameter) at Sonneberg Observatory.

  15. Gaia, an all-sky survey for standard photometry (United States)

    Carrasco, J. M.; Weiler, M.; Jordi, C.; Fabricius, C.


    Gaia ESA's space mission (launched in 2013) includes two low resolution spectroscopic instruments (one in the blue, BP, and another in the red, RP, wavelength domains) to classify and derive the astrophysical parameters of the observed sources. As it is well known, Gaia is a full-sky unbiased survey down to about 20th magnitude. The scanning law yields a rather uniform coverage of the sky over the full extent (a minimum of 5 years) of the mission. Gaia data reduction is a global one over the full mission. Both sky coverage and data reduction strategy ensure an unprecedented all-sky homogeneous spectrophotometric survey. Certainly, that survey is of interest for current and future on-ground and space projects, like LSST, PLATO, EUCLID and J-PAS/J-PLUS among others. These projects will benefit from the large amount (more than one billion) and wide variety of objects observed by Gaia with good quality spectrophotometry. Synthetic photometry derived from Gaia spectrophotometry for any passband can be used to expand the set of standard sources for these new instruments to come. In the current Gaia data release scenario, BP/RP spectrophotometric data will be available in the third release (in 2018, TBC). Current preliminary results allow us to estimate the precision of synthetic photometry derived from the Gaia data. This already allows the preparation of the on-going and future surveys and space missions. We discuss here the exploitation of the Gaia spectrophotometry as standard reference due to its full-sky coverage and its expected photometric uncertainties derived from the low resolution Gaia spectra.

  16. VizieR Online Data Catalog: Photometry and spectroscopy of KELT-11 (Pepper+, 2017) (United States)

    Pepper, J.; Rodriguez, J. E.; Collins, K. A.; Johnson, J. A.; Fulton, B. J.; Howard, A. W.; Beatty, T. G.; Stassun, K. G.; Isaacson, H.; Colon, K. D.; Lund, M. B.; Kuhn, R. B.; Siverd, R. J.; Gaudi, B. S.; Tan, T. G.; Curtis, I.; Stockdale, C.; Mawet, D.; Bottom, M.; James, D.; Zhou, G.; Bayliss, D.; Cargile, P.; Bieryla, A.; Penev, K.; Latham, D. W.; Labadie-Bartz, J.; Kielkopf, J.; Eastman, J. D.; Oberst, T. E.; Jensen, E. L. N.; Nelson, P.; Sliski, D. H.; Wittenmyer, R. A.; McCrady, N.; Wright, J. T.; Relles, H. M.; Stevens, D. J.; Joner, M. D.; Hintz, E.


    KELT-11b is located in the Kilodegree Extremely Little Telescope (KELT)-South field 23, which is centered at J2000 α=10h43m48s, δ=-20°00'00''. This field was monitored from UT 2010 March 12 to UT 2014 July 9, resulting in 3910 images after post-processing and removal of bad images. We obtained follow-up time-series photometry of KELT-11b. We obtained nine full or partial transits in multiple bands between 2015 January and 2016 February. We observed an ingress of KELT-11b from the Westminster College Observatory (WCO), PA, on UT 2015 January 1 in the I filter. The observations employed a 0.35m f/11 Celestron C14 Schmidt-Cassegrain telescope and SBIG STL-6303E CCD with a 3k*2k array of 9μm pixels, yielding a 24'*16' field of view and 1.4''/pixel image scale at 3*3 pixel binning. We observed a partial transit of KELT-11b using an 0.6m RCOS telescope at the Moore Observatory (MORC), operated by the University of Louisville. The telescope has an Apogee U16M 4K*4K CCD, giving a 26'*26' field of view and 0.39''/pixel. We observed the transit on UT 2015 February 08 in alternating Sloan g and i filters from before the ingress and past the mid-transit. We observed a transit of KELT-11b in the Sloan i-band using one of the Miniature Exoplanet Radial Velocity Array (MINERVA) Project telescopes (Swift et al. 2015JATIS...1b7002S) on the night of UT 2015 February 08. MINERVA used four 0.7m PlaneWave CDK-700 telescopes that are located on Mt. Hopkins, Arizona, at the Fred L. Whipple Observatory. While the four telescopes are normally used to feed a single spectrograph to discover and characterize exoplanets through radial velocity measurements, for the KELT-11 observations, we used a single MINERVA telescope in its photometric imaging mode. That telescope had an Andor iKON-L 2048*2048 camera, which gave a field of view of 20.9'*20.9' and a plate scale of 0.6''/pixel. The camera has a 2048*2048 back-illuminated deep depletion sensor with fringe suppression. Due to the


    Energy Technology Data Exchange (ETDEWEB)

    Matthews, Daniel J.; Newman, Jeffrey A. [Department of Physics and Astronomy, University of Pittsburgh, 3941 O' Hara Street, Pittsburgh, PA 15260 (United States); Coil, Alison L. [Department of Physics, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093 (United States); Cooper, Michael C. [Center for Galaxy Evolution, Department of Physics and Astronomy, University of California, Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States); Gwyn, Stephen D. J., E-mail:, E-mail:, E-mail:, E-mail:, E-mail: [Canadian Astronomical Data Centre, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, British Columbia V9E 2E7 (Canada)


    This paper describes a new catalog that supplements the existing DEEP2 Galaxy Redshift Survey photometric and spectroscopic catalogs with ugriz photometry from two other surveys: the Canada-France-Hawaii Legacy Survey (CFHTLS) and the Sloan Digital Sky Survey (SDSS). Each catalog is cross-matched by position on the sky in order to assign ugriz photometry to objects in the DEEP2 catalogs. We have recalibrated the CFHTLS photometry where it overlaps DEEP2 in order to provide a more uniform data set. We have also used this improved photometry to predict DEEP2 BRI photometry in regions where only poorer measurements were available previously. In addition, we have included improved astrometry tied to SDSS rather than USNO-A2.0 for all DEEP2 objects. In total this catalog contains {approx}27, 000 objects with full ugriz photometry as well as robust spectroscopic redshift measurements, 64% of which have r > 23. By combining the secure and accurate redshifts of the DEEP2 Galaxy Redshift Survey with ugriz photometry, we have created a catalog that can be used as an excellent testbed for future photo-z studies, including tests of algorithms for surveys such as LSST and DES.

  18. arXiv Single-electron and single-photon sensitivity with a silicon Skipper CCD

    CERN Document Server

    Tiffenberg, Javier; Drlica-Wagner, Alex; Essig, Rouven; Guardincerri, Yann; Holland, Steve; Volansky, Tomer; Yu, Tien-Tien


    We have developed ultralow-noise electronics in combination with repetitive, nondestructive readout of a thick, fully depleted charge-coupled device (CCD) to achieve an unprecedented noise level of 0.068  e- rms/pixel. This is the first time that discrete subelectron readout noise has been achieved reproducible over millions of pixels on a stable, large-area detector. This enables the contemporaneous, discrete, and quantized measurement of charge in pixels, irrespective of whether they contain zero electrons or thousands of electrons. Thus, the resulting CCD detector is an ultra-sensitive calorimeter. It is also capable of counting single photons in the optical and near-infrared regime. Implementing this innovative non-destructive readout system has a negligible impact on CCD design and fabrication, and there are nearly immediate scientific applications. As a particle detector, this CCD will have unprecedented sensitivity to low-mass dark matter particles and coherent neutrino-nucleus scattering, while ...


    National Aeronautics and Space Administration — This archive contains raw observations of the 2009-10-09 impact of the LCROSS spacecraft on the moon by the CCD47 camera on the MMT Observatory 6.5m telescope. The...

  20. Researchers develop CCD image sensor with 20ns per row parallel readout time

    CERN Multimedia

    Bush, S


    "Scientists at the Rutherford Appleton Laboratory (RAL) in Oxfordshire have developed what they claim is the fastest CCD (charge-coupled device) image sensor, with a readout time which is 20ns per row" (1/2 page)

  1. Emissions of chromium (VI) from arc welding. (United States)

    Heung, William; Yun, Myoung-Jin; Chang, Daniel P Y; Green, Peter G; Halm, Chris


    The presence of Cr in the +6 oxidation state (Cr[VI]) is still observed in ambient air samples in California despite steps taken to reduce emissions from plating operations. One known source of emission of Cr(VI) is welding, especially with high Cr-content materials, such as stainless steels. An experimental effort was undertaken to expand and update Cr(VI) emission factors by conducting tests on four types of arc-welding operations: gas-metal arc welding (GMAW), shielded metal arc welding (SMAW), fluxcore arc welding, and pulsed GMAW. Standard American Welding Society hood results were compared with a total enclosure method that permitted isokinetic sampling for particle size-cut measurement, as well as total collection of the aerosol. The fraction of Cr(VI) emitted per unit mass of Cr electrode consumed was determined. Consistent with AP-42 data, initial results indicate that a significant fraction of the total Cr in the aerosol is in the +6 oxidation state. The fraction of Cr(VI) and total aerosol mass produced by the different arc welding methods varies with the type of welding process used. Self-shielded electrodes that do not use a shield gas, for example, SMAW, produce greater amounts of Cr(VI) per unit mass of electrode consumed. The formation of Cr(VI) from standard electrode wires used for welding mild steel was below the method detection limit after eliminating an artifact in the analytical method used.

  2. Anaerobic bio-removal of uranium (VI) and chromium (VI): Comparison of microbial community structure

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande 1749-016 Lisboa (Portugal); Santos, Erika [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Maria Clara, E-mail: [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)


    Several microbial communities, obtained from uranium contaminated and non-contaminated samples, were investigated for their ability to remove uranium (VI) and the cultures capable for this removal were further assessed on their efficiency for chromium (VI) removal. The highest efficiency for removal of both metals was observed on a consortium from a non-contaminated soil collected in Monchique thermal place, which was capable to remove 91% of 22 mg L{sup -1} U(VI) and 99% of 13 mg L{sup -1} Cr(VI). This study revealed that uranium (VI) removing communities have also ability to remove chromium (VI), but when uranium (VI) was replaced by chromium (VI) several differences in the structure of all bacterial communities were observed. TGGE and phylogenetic analysis of 16S rRNA gene showed that the uranium (VI) removing bacterial consortia are mainly composed by members of Rhodocyclaceae family and Clostridium genus. On the other hand, bacteria from Enterobacteriaceae family were detected in the community with ability for chromium (VI) removal. The existence of members of Enterobacteriaceae and Rhodocyclaceae families never reported as chromium or uranium removing bacteria, respectively, is also a relevant finding, encouraging the exploitation of microorganisms with new abilities that can be useful for bioremediation.

  3. Colony Collapse Disorder (CCD) and bee age impact honey bee pathophysiology. (United States)

    vanEngelsdorp, Dennis; Traynor, Kirsten S; Andree, Michael; Lichtenberg, Elinor M; Chen, Yanping; Saegerman, Claude; Cox-Foster, Diana L


    Honey bee (Apis mellifera) colonies continue to experience high annual losses that remain poorly explained. Numerous interacting factors have been linked to colony declines. Understanding the pathways linking pathophysiology with symptoms is an important step in understanding the mechanisms of disease. In this study we examined the specific pathologies associated with honey bees collected from colonies suffering from Colony Collapse Disorder (CCD) and compared these with bees collected from apparently healthy colonies. We identified a set of pathological physical characteristics that occurred at different rates in CCD diagnosed colonies prior to their collapse: rectum distension, Malpighian tubule iridescence, fecal matter consistency, rectal enteroliths (hard concretions), and venom sac color. The multiple differences in rectum symptomology in bees from CCD apiaries and colonies suggest effected bees had trouble regulating water. To ensure that pathologies we found associated with CCD were indeed pathologies and not due to normal changes in physical appearances that occur as an adult bee ages (CCD colonies are assumed to be composed mostly of young bees), we documented the changes in bees of different ages taken from healthy colonies. We found that young bees had much greater incidences of white nodules than older cohorts. Prevalent in newly-emerged bees, these white nodules or cellular encapsulations indicate an active immune response. Comparing the two sets of characteristics, we determined a subset of pathologies that reliably predict CCD status rather than bee age (fecal matter consistency, rectal distension size, rectal enteroliths and Malpighian tubule iridescence) and that may serve as biomarkers for colony health. In addition, these pathologies suggest that CCD bees are experiencing disrupted excretory physiology. Our identification of these symptoms is an important first step in understanding the physiological pathways that underlie CCD and factors

  4. Colony Collapse Disorder (CCD) and bee age impact honey bee pathophysiology (United States)

    Traynor, Kirsten S.; Andree, Michael; Lichtenberg, Elinor M.; Chen, Yanping; Saegerman, Claude; Cox-Foster, Diana L.


    Honey bee (Apis mellifera) colonies continue to experience high annual losses that remain poorly explained. Numerous interacting factors have been linked to colony declines. Understanding the pathways linking pathophysiology with symptoms is an important step in understanding the mechanisms of disease. In this study we examined the specific pathologies associated with honey bees collected from colonies suffering from Colony Collapse Disorder (CCD) and compared these with bees collected from apparently healthy colonies. We identified a set of pathological physical characteristics that occurred at different rates in CCD diagnosed colonies prior to their collapse: rectum distension, Malpighian tubule iridescence, fecal matter consistency, rectal enteroliths (hard concretions), and venom sac color. The multiple differences in rectum symptomology in bees from CCD apiaries and colonies suggest effected bees had trouble regulating water. To ensure that pathologies we found associated with CCD were indeed pathologies and not due to normal changes in physical appearances that occur as an adult bee ages (CCD colonies are assumed to be composed mostly of young bees), we documented the changes in bees of different ages taken from healthy colonies. We found that young bees had much greater incidences of white nodules than older cohorts. Prevalent in newly-emerged bees, these white nodules or cellular encapsulations indicate an active immune response. Comparing the two sets of characteristics, we determined a subset of pathologies that reliably predict CCD status rather than bee age (fecal matter consistency, rectal distension size, rectal enteroliths and Malpighian tubule iridescence) and that may serve as biomarkers for colony health. In addition, these pathologies suggest that CCD bees are experiencing disrupted excretory physiology. Our identification of these symptoms is an important first step in understanding the physiological pathways that underlie CCD and factors

  5. Colony Collapse Disorder (CCD and bee age impact honey bee pathophysiology.

    Directory of Open Access Journals (Sweden)

    Dennis vanEngelsdorp

    Full Text Available Honey bee (Apis mellifera colonies continue to experience high annual losses that remain poorly explained. Numerous interacting factors have been linked to colony declines. Understanding the pathways linking pathophysiology with symptoms is an important step in understanding the mechanisms of disease. In this study we examined the specific pathologies associated with honey bees collected from colonies suffering from Colony Collapse Disorder (CCD and compared these with bees collected from apparently healthy colonies. We identified a set of pathological physical characteristics that occurred at different rates in CCD diagnosed colonies prior to their collapse: rectum distension, Malpighian tubule iridescence, fecal matter consistency, rectal enteroliths (hard concretions, and venom sac color. The multiple differences in rectum symptomology in bees from CCD apiaries and colonies suggest effected bees had trouble regulating water. To ensure that pathologies we found associated with CCD were indeed pathologies and not due to normal changes in physical appearances that occur as an adult bee ages (CCD colonies are assumed to be composed mostly of young bees, we documented the changes in bees of different ages taken from healthy colonies. We found that young bees had much greater incidences of white nodules than older cohorts. Prevalent in newly-emerged bees, these white nodules or cellular encapsulations indicate an active immune response. Comparing the two sets of characteristics, we determined a subset of pathologies that reliably predict CCD status rather than bee age (fecal matter consistency, rectal distension size, rectal enteroliths and Malpighian tubule iridescence and that may serve as biomarkers for colony health. In addition, these pathologies suggest that CCD bees are experiencing disrupted excretory physiology. Our identification of these symptoms is an important first step in understanding the physiological pathways that underlie CCD and

  6. Preliminary examination of a CCD camera with a scintillator coated fiber optic plate for neutron imaging (United States)

    Matsubayashi, Masahito; Soyama, Kazuhiko


    A charge coupled device (CCD) camera with a scintillator coated fiber optic plate (FOP) was examined for neutron imaging. The FOP coupling and the lens coupling in terms of efficient optical coupling with a CCD, and 6LiF:ZnS(Ag) and Gd 2O 2S(Tb) in terms of light emission efficiency and spatial resolution were discussed. The spatial resolution for each imaging system was obtained as edge spread functions or observations of modulation transfer function charts.

  7. Practical performance evaluation of a 10k × 10k CCD for electron cryo-microscopy. (United States)

    Bammes, Benjamin E; Rochat, Ryan H; Jakana, Joanita; Chiu, Wah


    Electron cryo-microscopy (cryo-EM) images are commonly collected using either charge-coupled devices (CCD) or photographic film. Both film and the current generation of 16 megapixel (4k × 4k) CCD cameras have yielded high-resolution structures. Yet, despite the many advantages of CCD cameras, more than two times as many structures of biological macromolecules have been published in recent years using photographic film. The continued preference to film, especially for subnanometer-resolution structures, may be partially influenced by the finer sampling and larger effective specimen imaging area offered by film. Large format digital cameras may finally allow them to overtake film as the preferred detector for cryo-EM. We have evaluated a 111-megapixel (10k × 10k) CCD camera with a 9 μm pixel size. The spectral signal-to-noise ratios of low dose images of carbon film indicate that this detector is capable of providing signal up to at least 2/5 Nyquist frequency potentially retrievable for 3D reconstructions of biological specimens, resulting in more than double the effective specimen imaging area of existing 4k × 4k CCD cameras. We verified our estimates using frozen-hydrated ε15 bacteriophage as a biological test specimen with previously determined structure, yielding a ∼7 Å resolution single particle reconstruction from only 80 CCD frames. Finally, we explored the limits of current CCD technology by comparing the performance of this detector to various CCD cameras used for recording data yielding subnanometer resolution cryo-EM structures submitted to the electron microscopy data bank ( Copyright © 2011 Elsevier Inc. All rights reserved.

  8. JAstroCam - A New Tool for Data Gathering with CCD (United States)

    Budyn, M.; Zola, S.; Wojcik, K.


    We present a new acquisition program for observations with CCD. The code is written in the JAVA language, currently supports Photometrics S300, SBIG, APOGEE and Andor CCDs. New hardware support can be extended by adding plugins for either a new type of CCD or a filter wheel. The software is capable of performing an on-line reduction of frames coming in real time either on non-processed or reduced for bias/dark/flat frames.

  9. Learning the vi and Vim Editor

    CERN Document Server

    Robbins, Arnold; Hannah, Elbert


    There's nothing that hard-core Unix and Linux users are more fanatical about than their text editor. Editors are the subject of adoration and worship, or of scorn and ridicule, depending upon whether the topic of discussion is your editor or someone else's. vi has been the standard editor for close to 30 years. Popular on Unix and Linux, it has a growing following on Windows systems, too. Most experienced system administrators cite vi as their tool of choice. And since 1986, this book has been the guide for vi. However, Unix systems are not what they were 30 years ago, and neither is this

  10. Mucopolissacaridose tipo VI: relato de caso


    Lais Orosco Bialon Santana; Carolina Ando Matsuno; Marta Wey Vieira


    Introdução: As mucopolissacaridoses são erros inatos do metabolismo de depósito lisossomal subclassificadas segundo a enzima deficiente. A arilsulfatase B (ARSB), responsável por degradar os glicosaminoglicanos (GAGs), que atuam no tecido conjuntivo, é deficiente na mucopolissacaridose tipo VI (MP VI). A MP VI tem clínica variável, sem anormalidades ao nascimento, evidenciando-se progressivamente ao acúmulo de GAGs. O diagnóstico se faz pela redução da atividade da ARSB ou da mutação genética...

  11. A Design and Development of Multi-Purpose CCD Camera System with Thermoelectric Cooling: Software

    Directory of Open Access Journals (Sweden)

    S. H. Oh


    Full Text Available We present a software which we developed for the multi-purpose CCD camera. This software can be used on the all 3 types of CCD - KAF-0401E (768×512, KAF-1602E (15367times;1024, KAF-3200E (2184×1472 made in KODAK Co.. For the efficient CCD camera control, the software is operated with two independent processes of the CCD control program and the temperature/shutter operation program. This software is designed to fully automatic operation as well as manually operation under LINUX system, and is controled by LINUX user signal procedure. We plan to use this software for all sky survey system and also night sky monitoring and sky observation. As our results, the read-out time of each CCD are about 15sec, 64sec, 134sec for KAF-0401E, KAF-1602E, KAF-3200E., because these time are limited by the data transmission speed of parallel port. For larger format CCD, the data transmission is required more high speed. we are considering this control software to one using USB port for high speed data transmission.

  12. High-Speed and Wide-Field Photometry with TORTORA

    Directory of Open Access Journals (Sweden)

    G. Greco


    Full Text Available We present the photometric analysis of the extended sky fields observed by the TORTORA optical monitoring system. The technology involved in the TORTORA camera is based on the use of a fast TV-CCD matrix with an image intensifier. This approach can both significantly reduce the readout noise and shorten the focal length following to monitor relatively large sky regions with high temporal resolution and adequate detection limit. The performance of the system has been tested using the relative magnitudes of standard stars by means of long image sequences collected at different airmasses and at various intensities of the moon illumination. As expected from the previous laboratory measurements, artifact sources are negligible and do not affect the photometric results. The following analysis is based on a large sample of images acquired by the TORTORA instrument since July 2006.

  13. ViSIT: Visitor Survey Information Tool (United States)

    US Fish and Wildlife Service, Department of the Interior — ViSIT is an interactive web tool created by USGS to visualize the data collected as part of the National Wildlife Refuge Visitor Survey. The national survey was...

  14. Derfor elsker og hader vi positiv psykologi

    DEFF Research Database (Denmark)

    Mehlsen, Camilla


    Hvorfor er positiv psykologi så populært? Er positiv psykologi ved at blive en religion? Asterisk har mødt tre fremtrædende forskere, der forklarer, hvorfor vi elsker og hader positiv psykolog.......Hvorfor er positiv psykologi så populært? Er positiv psykologi ved at blive en religion? Asterisk har mødt tre fremtrædende forskere, der forklarer, hvorfor vi elsker og hader positiv psykolog....

  15. Kan vi forebygge en kompliceret sorgreaktion?

    DEFF Research Database (Denmark)

    Nielsen, Mette Kjærgaard; Guldin, Mai-Britt


    Pårørende til alvorligt syge patienter er i en sårbar situation og risikerer selv at blive syge. Som sundhedsprofessionelle har vi mulighed for at støtte pårørende i palliative forløb, og vi vil i denne artikel beskrive mulige prædiktorer for kompliceret sorg og depression hos den pårørende efter...

  16. Hvad skal vi med Trump-satire?

    DEFF Research Database (Denmark)

    Møller, Mette


    Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til? Link:

  17. SaVi: satellite constellation visualization


    Wood, Lloyd


    SaVi, a program for visualizing satellite orbits, movement, and coverage, is maintained at the University of Surrey. This tool has been used for research in academic papers, and by industry companies designing and intending to deploy satellite constellations. It has also proven useful for demonstrating aspects of satellite constellations and their geometry, coverage and movement for educational and teaching purposes. SaVi is introduced and described briefly here.


    National Aeronautics and Space Administration — This data set contains raw and reduced mid-infrared images and photometry of comet 9P/Tempel 1, the target of the Deep Impact mission. Images were acquired on the...

  19. Intelligent real-time CCD data processing system based on variable frame rate (United States)

    Chen, Su-ting


    In order to meet the need of image shooting with CCD in unmanned aerial vehicles, a real-time high resolution CCD data processing system based on variable frame rate is designed. The system is consisted of three modules: CCD control module, data processing module and data display module. In the CCD control module, real-time flight parameters (e.g. flight height, velocity and longitude) should be received from GPS through UART (Universal Asynchronous Receiver Transmitter) and according to the corresponding flight parameters, the variable frame rate is calculated. Based on the calculated variable frame rate, CCD external synchronization control impulse signal is generated in the control of FPGA and then CCD data is read out. In the data processing module, data segmentation is designed to extract ROI (region of interest), whose resolution is equal to valid data resolution of HDTV standard conforming to SMPTE (1080i). On one hand, Ping-pong SRAM storage controller is designed in FPGA to real-time store ROI data. On the other hand, according to the need of intelligent observing, changeable window position is designed, and a flexible area of interest is obtained. In the real-time display module, a special video encoder is used to accomplish data format conversion. Data after storage is packeted to HDTV format by creating corresponding format information in FPGA. Through inner register configuration, high definition video analog signal is implemented. The entire system has been implemented in FPGA and validated. It has been used in various real-time CCD data processing situations.


    Energy Technology Data Exchange (ETDEWEB)

    Beky, Bence; Holman, Matthew J.; Noyes, Robert W.; Sasselov, Dimitar D. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 (United States); Gilliland, Ronald L. [Center for Exoplanets and Habitable Worlds, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Bakos, Gaspar A. [Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544 (United States); Winn, Joshua N., E-mail: [Department of Physics, and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 70 Vassar Street, Cambridge, MA 02139 (United States)


    We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph observations of two occultations of the transiting exoplanet HAT-P-1b. By measuring the planet to star flux ratio near opposition, we constrain the geometric albedo of the planet, which is strongly linked to its atmospheric temperature gradient. An advantage of HAT-P-1 as a target is its binary companion ADS 16402 A, which provides an excellent photometric reference, simplifying the usual steps in removing instrumental artifacts from HST time-series photometry. We find that without this reference star, we would need to detrend the lightcurve with the time of the exposures as well as the first three powers of HST orbital phase, and this would introduce a strong bias in the results for the albedo. However, with this reference star, we only need to detrend the data with the time of the exposures to achieve the same per-point scatter, therefore we can avoid most of the bias associated with detrending. Our final result is a 2{sigma} upper limit of 0.64 for the geometric albedo of HAT-P-1b between 577 and 947 nm.

  1. Integrated radar-photometry sensor based on constrained optical flow (United States)

    Fablet, Youenn; Agam, Gady; Cohen, Paul


    Robotic teleoperation is a major research area with numerous applications. Efficient teleoperation, however, greatly depends on the provided sensory information. In this paper, an integrated radar- photometry sensor is presented. The developed sensor relies on the strengths of the two main modalties: robust radar-based range data, and high resolution dynamic photometric imaging. While radar data has low resolution and depth from motion in photometric images is susceptible to poor visibility conditions, the integrated sensor compensates for the flaws of the individual components. The integration of the two modalities is achieved by us ing the radar based range data in order to constrain the optical flow estimation, and fusing the resulting depth maps. The optical flow computation is constrained by a model flow field based upon the radar data, by using a rigidity constraint, and by incorporating edge information into the optical flow estimation. The data fusion is based upon a confidence estimation of the image based depth computation. Results with simulated data demonstrate the good potential of the approach.

  2. GASPS Photometry of the Tucana-Horologium Association (United States)

    Roberge, Donaldson J.; Roberge, Aki


    The GASPS Open Time Key Programme on Herschel represents a new opportunity to sensitively probe protoplanetary and debris disks at far-IR wavelengths. We present preliminary PACS 70 and 160 micron photometry of eighteen stars in the 30 Myr-old Tucana-Horologium association. Of these eighteen, eight were detected in the 70 micron band. Four of these eight were also detected in the 160 micron band. We constructed SEDs for these systems using optical data from Hipparcos (B and V), near-IR data from 2MASS (J, H, and K), mid-IR data from IRAS and Spitzer MIPS (12 and 24 microns, respectively), and the new far-IR data from PACS. For the stars showing IR excess emission, we fit simple single-temperature blackbody curves to the IR excess in order to determine the rough dust abundances and temperatures. Dust observations at these wavelengths will also be important for comparison with upcoming Herschel PACS spectra that will search for gas in the disks. Our goal is to determine or limit the ever-allusive gas-to-dust ratio for these disk systems.

  3. Herschel Photometry of the Tucana-Horologium Association (United States)

    Donaldson, Jessica; Roberge, A.; Dent, W.


    The GASPS Open Time Key Programme for the Herschel Space Observatory represents a new opportunity to survey protoplanetary disks and young debris disks at far-IR wavelengths. We present preliminary PACS 70 and 160 micron photometry of eighteen stars in the 30 Myr-old Tucana-Horologium association. Of these eighteen, six were detected in the 70 micron band. Two were also detected in the 160 micron band. We constructed SEDs for these systems using optical data from Hipparcos (B and V), near-IR data from 2MASS (J, H, and K), mid-IR data from IRAS and Spitzer MIPS (12 and 24 microns, respectively), and the new far-IR data from PACS. For the stars showing IR excess emission, we fit the data using models of optically thin debris disks with realistic dust grain properties. Our SED fitting constrains six disk parameters: the disk mass, grain size distribution, minimum and maximum grain sizes, and the minimum and maximum radial distance of the disk. The best-fit parameters give us a sense of the dust abundance and spatial distribution in these systems.

  4. Accuracy of stellar parameters determined from multicolor photometry (United States)

    Sichevskij, S. G.; Mironov, A. V.; Malkov, O. Yu.


    The development and application of new methods for intelligent analysis and extraction of information from digital sky surveys carried out in various spectral domains have now become a popular field in astrophysical research and, in particular, in stellar studies. Modern large-scale photometric surveys provide data for 105-106 relatively faint objects, and the lack of spectroscopic data can be compensated by the cross identification of the objects followed by an analysis of all catalogued photometric data. In this paper we investigate the possibility of determining the effective temperature, surface gravity, total extinction, and the total-to-selective extinction ratio based on the photometry provided in the 2MASS, SDSS, and GALEX surveys, and estimate the accuracy of the inferred parameters. We use a library of theoretical spectra to compute the magnitudes of stars in the photometric bands of the above surveys for various sets of input parameters. We compare the differences between the computed magnitudes with the errors of the corresponding surveys. We find that stellar parameters can be computed over a sizable domain of the parameter space. We estimate the accuracy of the resulting parameters. We show that the presence of far-ultraviolet data in the available set of observed magnitudes increases the accuracy of the inferred parameters.

  5. macula: Rotational modulations in the photometry of spotted stars (United States)

    Kipping, David M.


    Photometric rotational modulations due to starspots remain the most common and accessible way to study stellar activity. Modelling rotational modulations allows one to invert the observations into several basic parameters, such as the rotation period, spot coverage, stellar inclination and differential rotation rate. The most widely used analytic model for this inversion comes from Budding (1977) and Dorren (1987), who considered circular, grey starspots for a linearly limb darkened star. That model is extended to be more suitable in the analysis of high precision photometry such as that by Kepler. Macula, a Fortran 90 code, provides several improvements, such as non-linear limb darkening of the star and spot, a single-domain analytic function, partial derivatives for all input parameters, temporal partial derivatives, diluted light compensation, instrumental offset normalisations, differential rotation, starspot evolution and predictions of transit depth variations due to unocculted spots. The inclusion of non-linear limb darkening means macula has a maximum photometric error an order-of-magnitude less than that of Dorren (1987) for Sun-like stars observed in the Kepler-bandpass. The code executes three orders-of-magnitude faster than comparable numerical codes making it well-suited for inference problems.

  6. Photometry of some more neglected bright cataclysmic variables and candidates (United States)

    Bruch, Albert


    As part of an effort to better characterize bright cataclysmic variables (CVs) and related systems which have received little attention in the past light curves of four systems (V504 Cen, KT Eri, Ret 1 and CTCV 2056-3014) are analyzed. For some of these stars no time resolved photometry has been published previously. While flickering is observed in all systems except Ret 1, it is particularly strong in V504 Cen and CTCV 2056-3014. In the latter star, a previously observed 15.4 m period, leading to its tentative classification as an intermediate polar, is probably spurious. Variations on time scales of hundredths of days observed in the pre-outburst light curve of the classical nova KT Eri continue after the outburst but appear not to be strictly periodic. Furthermore, the long term post-outburst light curve exhibits modulations with quasi-periods of quite different length. Thus, these variations cannot be due to aspect related variations in a system with a giant component similar to some recurrent novae. Instead, the system possibly exhibits variations with a period of 0.1952 d which may be orbital. However, any such conclusion still requires confirmation. The absence of flickering in Ret 1 indicates that the system probably does not contain an accretion disk. Instead, the observation of slow variations supports a previous suspicion of low amplitude variability with a period >12 h.

  7. Photometry of some neglected bright cataclysmic variables and candidates (United States)

    Bruch, Albert


    As part of an effort to better characterize bright cataclysmic variables (CVs) which have received little attention in the past light curves of four confirmed systems (CZ Aql, BO Cet, V380 Oph and EF Tuc) and one candidate (Lib 3) are analyzed. For none of these stars time resolved photometry has been published previously. While no variability was found in the case of Lib 3, which thus cannot be confirmed as a CV, the light curves of all other targets are dominated by strong flickering. Modulations on hourly time scales superimposed on the flickering can probably be related to orbital variations in BO Cet and V380 Oph, but not in CZ Aql and EF Tuc. Variations on the time scale of 10 min in CZ Aql, while not yet constituting convincing evidence, together with previous suspicions of a magnetically channeled accretion flow may point at an intermediate polar nature of this star. Some properties of the flickering are quantified in an effort to enlarge the data base for future comparative flickering studies in CVs and to refine the classification of the target stars.

  8. Development and evaluation of a CCD-based digital imaging system for mammography (United States)

    Piccaro, Michele F.; Toker, Emre


    We have developed a CCD-based, high performance, filmless imaging system for stereotactic biopsy procedures in mammography. The CCD camera is based on a 1024 X 1024 pixel format, full-frame, scientific grade, front-illuminated, MPP mode CCD, directly coupled to an X-ray intensifying screen via a 2:1 fiber optic reducer. The CCD is cooled to -10 degree(s)C, and is digitized in slow-scan, correlated double sampling mode at 500 Kpixels/second with 12-bit contrast resolution. X-ray images acquired with the system are processed and displayed on a high resolution monitor within 20 seconds of exposure. System design and specifications will be described, and evaluation of physical performance characteristics will be discussed. The system has been used in over 100 stereotactic breast biopsy procedures to date, and has been shown to significantly improve the speed and accuracy of the biopsy procedure, due to the near real-time acquisition and display of x-ray images. Initial results also indicate that the fiber optic coupled CCD-based imaging system provides superior detectability of low contrast breast lesions and microcalcifications at lower patient dose, as compared to conventional film-screen detectors.

  9. The DEdicated MONitor of EXotransits and Transients (DEMONEXT): a Robotic Observatory for Follow-Up of Transiting Exoplanets, Transients, and Time-Series Photometry (United States)

    Villanueva, Steven; Gaudi, B. Scott; Pogge, Richard; Stassun, Keivan G.; Eastman, Jason; Trueblood, Mark; Trueblood, Pat


    The DEdicated MONitor of EXotransits and Transients (DEMONEXT) is a 20 inch (0.5-m) robotic telescope that has been in operation since May 2016. Fully automated, DEMONEXT has observed over 150 transits of exoplanet candidates for the KELT survey, including confirmation observations of KELT-20b. DEMONEXT achieves 2-4 mmag precision with unbinned, 20-120 second exposures, on targets orbiting V<13 host stars. Millimagnitude precision can be achieved by binning the transits on 5-6 minute timescales. During observations of 8 hours with hundreds of consecutive exposures, DEMONEXT maintains sub-pixel (<0.5 pixels) target position stability on the CCD during good observing conditions, with degraded performance during poor observing conditions (<1 pixel). DEMONEXT achieves 1% photometry on targets with V<17 in 5 minute exposures, with detection limits of V~21. In addition to the 150 transits observed by DEMONEXT, 50 supernovae and transients haven been observed for the ASAS-SN supernovae group, as well as time-series observations of Galactic microlensing, active galactic nuclei, stellar variability, and stellar rotation.

  10. Quantum efficiency modeling for a thick back-illuminated astronomical CCD (United States)

    Groom, D. E.; Haque, S.; Holland, S. E.; Kolbe, W. F.


    The quantum efficiency and reflectivity of thick, back-illuminated CCD's being fabricated at the Lawrence Berkeley National Laboratory for astronomical applications are modeled and compared with experiments. The treatment differs from standard thin-film optics in that (a) absorption is permitted in any film, (b) the 200-500 μm thick silicon substrate is considered as a thin film in order to observe the fringing behavior at long wavelengths, and (c) by using approximate boundary conditions, absorption in the surface films is separated from absorption in the substrate. For quantum efficiency measurements, the CCD's are normally operated as CCD's, usually at T =-140 ° C, and at higher temperatures, as photodiodes. They are mounted on mechanical substrates. Reflectivity is measured on air-backed wafer samples at room temperature. The agreement between model expectation and quantum efficiency measurement is in general satisfactory.

  11. High-aperture monochromator-reflectometer and its usefulness for CCD calibration (United States)

    Vishnyakov, Eugene A.; Shcherbakov, Alexander V.; Pertsov, Andrei A.; Polkovnikov, Vladimir N.; Pestov, Alexey E.; Pariev, Dmitry E.; Chkhalo, Nikolai I.


    We present a laboratory high-aperture monochromator-reflectometer employing laser-plasma radiation source and three replaceable Schwarzschild objectives for a certain range of applications in the soft X-ray spectral waveband. Three sets of X-ray multilayer mirrors for the Schwarzschild objectives enable operation of the reflectometer at the wavelengths of 135, 171 and 304 Å, while a goniometer with three degrees of freedom allows different measurement modes. We have used the facility for a laboratory CCD calibration at the wavelengths specified. Combined with the results of the CCD sensitivity measurements conducted in the VUV spectral waveband, the total outcome provides a more comprehensive understanding of the CCD effectivity in a wide spectral range.

  12. Investigation of the radiation performance of CCD sensors in a vertex detector application

    CERN Document Server

    Stefanov, K D; Miyamoto, A; Sugimoto, Y; Tamura, N; Takahashi, S; Abe, K; Nagamine, T; Aso, T


    The radiation performance of a Hamamatsu S5466 and an EEV CCD02-06 silicon CCD sensors, working in a Multi-Pinned Phase (MPP) mode has been evaluated, in view of their possible use in the vertex detector of a future linear collider. We have examined the influence of the electron irradiation from a beta-source with fluencies up to 4.3x10 sup 1 sup 2 e sup - /cm sup 2 on the parameters of the CCD sensors such as dark current, dark current spikes, drive pulse voltages and charge transfer inefficiency (CTI). The changes of the parameters of the devices resulting from the irradiation are reported and discussed.

  13. Magneto-optic Kerr effect CCD imaging with polarization modulation technique

    Directory of Open Access Journals (Sweden)

    Satoru Nakayama


    Full Text Available We have developed a magneto-optic Kerr effect (MOKE imaging system with a charge-coupled-device (CCD camera by using the rotating compensator technique. We chose optimal conditions of the rotation frequency of the compensator with stable rotation along with a CCD camera frame rate that allowed precise control of the exposure timing in order to link with the angle of the compensator. Precise timing management of the CCD exposure enables us to carry out repeated experiments, which greatly improves the signal-to-noise ratio of the longitudinal MOKE signal. We applied the technique to the material characterization of the Ni81 Fe19 thin film and its microstructure, and succeeded in evaluating the spatial variation of the complex magneto-optic constant Q of the sample. Because of its attractive advantages such as high-speed and compactness, the present method provides a novel platform for investigating the domain structures in various magnetic materials.

  14. Magneto-optic Kerr effect CCD imaging with polarization modulation technique (United States)

    Nakayama, Satoru; Okano, Makoto; Nozaki, Yukio; Watanabe, Shinichi


    We have developed a magneto-optic Kerr effect (MOKE) imaging system with a charge-coupled-device (CCD) camera by using the rotating compensator technique. We chose optimal conditions of the rotation frequency of the compensator with stable rotation along with a CCD camera frame rate that allowed precise control of the exposure timing in order to link with the angle of the compensator. Precise timing management of the CCD exposure enables us to carry out repeated experiments, which greatly improves the signal-to-noise ratio of the longitudinal MOKE signal. We applied the technique to the material characterization of the Ni81 Fe19 thin film and its microstructure, and succeeded in evaluating the spatial variation of the complex magneto-optic constant Q of the sample. Because of its attractive advantages such as high-speed and compactness, the present method provides a novel platform for investigating the domain structures in various magnetic materials.

  15. Retrieval of absorption and backscattering coefficients from HJ-1A/CCD imagery in coastal waters. (United States)

    Chen, Jun; Quan, Wenting; Yao, Guoqing; Cui, Tingwei


    A simple semi-analytical model (SAB) was developed for computing a(560) and b(b)(550) from HJ-1A/CCD images. By comparison with field measurements, the SAB model produces 5.3-23.5% uncertainty for a(560) and b(b)(550) retrievals. The a(560) and b(b)(550) are also retrieved from satellite images. The match-up analysis results indicate that a(560) and b(b)(550) may be derived from the HJ-1A/CCD images with respective uncertainties of 29.84 and 21.35%. These findings imply that, provided that an atmospheric correction scheme for the green bands is available, the extensive database of HJ-1A/CCD imagery may be used for the quantitative monitoring of optical properties in coastal waters.

  16. U(VI) biosorption by bi-functionalized Pseudomonas putida @ chitosan bead: Modeling and optimization using RSM. (United States)

    Sohbatzadeh, Hozhabr; Keshtkar, Ali Reza; Safdari, Jaber; Fatemi, Faezeh


    In this work, Pseudomonas putida cells immobilized into chitosan beads (PICB) were synthesized to investigate the impact of microorganism entrapment on biosorption capacity of prepared biosorbent for U(VI) biosorption from aqueous solutions. Response Surface Methodology (RSM) based on Central Composite Design (CCD) was utilized to evaluate the performance of the PICB in comparison with chitosan beads (CB) under batch mode. Performing experiments under optimal condition sets viz. pH 5, initial U(VI) concentration 500mg/L, biosorbent dosage 0.4g/L and 20wt.% bacterial cells showed that the observed biosorption capacity enhanced by 1.27 times from 398mg/g (CB) to 504mg/g (PICB) that confirmed the effectiveness of cells immobilization process. FTIR and potentiometric titration were then utilized to characterize the prepared biosorbents. While the dominant functional group in the binding process was NH3(+) (4.78meq/g) in the CB, the functional groups of NH3(+), NH2, OH, COOH (6.00meq/g) were responsible for the PICB. The equilibrium and kinetic studies revealed that the Langmuir isotherm model and the pseudo-second-order kinetic model were in better fitness with the CB and PICB experimental data. In conclusion, the present study indicated that the PICB could be a suitable biosorbent for uranium (VI) biosorption from aqueous solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. DustPedia: Multiwavelength photometry and imagery of 875 nearby galaxies in 42 ultraviolet-microwave bands (United States)

    Clark, C. J. R.; Verstocken, S.; Bianchi, S.; Fritz, J.; Viaene, S.; Smith, M. W. L.; Baes, M.; Casasola, V.; Cassara, L. P.; Davies, J. I.; De Looze, I.; De Vis, P.; Evans, R.; Galametz, M.; Jones, A. P.; Lianou, S.; Madden, S.; Mosenkov, A. V.; Xilouris, M.


    Aims: The DustPedia project is capitalising on the legacy of the Herschel Space Observatory, using cutting-edge modelling techniques to study dust in the 875 DustPedia galaxies - representing the vast majority of extended galaxies within 3000 km s-1 that were observed by Herschel. This work requires a database of multiwavelength imagery and photometry that greatly exceeds the scope (in terms of wavelength coverage and number of galaxies) of any previous local-Universe survey. Methods: We constructed a database containing our own custom Herschel reductions, along with standardised archival observations from GALEX, SDSS, DSS, 2MASS, WISE, Spitzer, and Planck. Using these data, we performed consistent aperture-matched photometry, which we combined with external supplementary photometry from IRAS and Planck. Results: We present our multiwavelength imagery and photometry across 42 UV-microwave bands for the 875 DustPedia galaxies. Our aperture-matched photometry, combined with the external supplementary photometry, represents a total of 21 857 photometric measurements. A typical DustPedia galaxy has multiwavelength photometry spanning 25 bands. We also present the Comprehensive & Adaptable Aperture Photometry Routine (CAAPR), the pipeline we developed to carry out our aperture-matched photometry. CAAPR is designed to produce consistent photometry for the enormous range of galaxy and observation types in our data. In particular, CAAPR is able to determine robust cross-compatible uncertainties, thanks to a novel method for reliably extrapolating the aperture noise for observations that cover a very limited amount of background. Our rich database of imagery and photometry is being made available to the community. Photometry data tables are only available at the CDS via anonymous ftp to ( or via

  18. Time-series high-resolution spectroscopy and photometry of ɛ Aurigae from 2006-2013: Another brick in the wall (United States)

    Strassmeier, K. G.; Weber, M.; Granzer, T.; Schanne, L.; Bartus, J.; Ilyin, I.


    We present continuous and time-resolved R = 55 000 optical échelle spectroscopy of ɛ Aurigae from 2006-2013. Data were taken with the STELLA Echelle Spectrograph of the robotic STELLA facility at the Observatorio del Teide in Tenerife. Contemporaneous photometry with the Automatic Photoelectric Telescopes at Fairborn Observatory in Arizona is presented for the years 1996-2013. Spectroscopic observations started three years prior to the photometric eclipse and are still ongoing. A total of 474 high-resolution échelle spectra are analyzed and made available in this paper. We identify 368 absorption lines of which 161 lines show the characteristic sharp disk lines during eclipse. Another 207 spectral lines appeared nearly unaffected by the eclipse. From spectrum synthesis, we obtained the supergiant atmospheric parameters T_eff = 7395±70 K, log g≈ 1, and [Fe/H] = +0.02±0.2 with ξ_t = 9 km s-1 , ζ_RT = 13 km s-1 , and v sin i = 28±3 km s-1 . The residual average line broadening expressed in km s-1 varies with a period of 62.6±0.7 d, in particular at egress and after the eclipse. Two-dimensional line-profile periodograms show several periods, the strongest with ≈110 d evident in optically thin lines as well as in the Balmer lines. Center-of-intensity weighted radial velocities of individual spectral lines also show the 110-d period but, again, additional shorter and longer periods are evident and are different in the Balmer lines. The two main spectroscopic Hα periods, ≈ 116 d from the line core and ≈ 150 d from the center-of-intensity radial velocities, appear at 102 d and 139 d in the photometry. The Hβ and Johnson VI photometry on the other hand shows two well-defined and phase-coherent periods of 77 d and 132 d. We conclude that Hα is contaminated by changes in the circumstellar environment while the Hβ and VI photometry stems predominantly from the non radial pulsations of the F0 supergiant. We isolate the disk-rotation profile from 61

  19. Aperture Photometry Tool Versus SExtractor for Noncrowded Fields (United States)

    Laher, Russ R.; Rebull, Luisa M.; Gorjian, Varoujan; Masci, Frank J.; Fowler, John W.; Grillmair, Carl; Surace, Jason; Mattingly, Sean; Jackson, Ed; Hacopeans, Eugean; Hamam, Nouhad; Groom, Steve; Teplitz, Harry; Mi, Wei; Helou, George; van Eyken, Julian C.; Law, Nicholas M.; Dekany, Richard G.; Rahmer, Gustavo; Hale, David; Smith, Roger; Quimby, Robert M.; Ofek, Eran O.; Kasliwal, Mansi M.; Zolkower, Jeff; Velur, Viswa; Walters, Richard; Henning, John; Bui, Khahn; McKenna, Dan; Kulkarni, Shrinivas R.


    Outputs from new software program Aperture Photometry Tool (APT) are compared with similar outputs from SExtractor for sources extracted from R-band optical images acquired by the Palomar Transient Factory (PTF), infrared mosaics constructed from Spitzer Space Telescope images, and a processed visible/near-infrared image from the Hubble Legacy Archive (HLA). Two large samples from the PTF images are studied, each containing around 3 × 103 sources from noncrowded fields. The median values of source-intensity relative percentage differences between the two software programs, computed separately for two PTF samples, are +0.13% and +0.17%, with corresponding statistical dispersions of 1.43% and 1.84%, respectively. For the Spitzer mosaics, a similar large sample of extracted sources for each of channels 1-4 of Spitzer’s Infrared Array Camera (IRAC) are analyzed with two different sky annulus sizes, and we find that the median and modal values of source-intensity relative percentage differences between the two software programs are between -0.5% and +2.0%, and the corresponding statistical dispersions range from 1.4 to 6.7%, depending on the Spitzer IRAC channel and sky annulus. The results for the HLA image are mixed, as might be expected for a moderately crowded field. The comparisons for the three different kinds of images show that there is generally excellent agreement between APT and SExtractor. Differences in source-intensity uncertainty estimates for the PTF images amount to less than 3% for the PTF sources, and these are potentially caused by SExtractor’s omission of the sky background uncertainty term in the formula for source-intensity uncertainty, as well as differing methods of sky background estimation.

  20. Odd Harmonics in Exoplanet Photometry: Weather or Artifact? (United States)

    Cowan, Nicolas B.; Chayes, Victoria; Bouffard, Élie; Meynig, Max; Haggard, Hal M.


    In addition to the transits of a planet in front of its star and the eclipses of the planet by its star, researchers have reported flux variations at the orbital frequency and its harmonics: planetary reflection and/or emission and Doppler beaming of starlight produce one peak per orbit, while ellipsoidal variations of a tidally distorted star and/or planet produce two maxima per orbit. Researchers have also reported significant photometric variability at three times the orbital frequency, as yet unexplained. Reflected phase variations of homogeneous planets only contain power at the orbital frequency and its even harmonics. We show that odd harmonics can, however, be produced by an edge-on planet with a time-variable map, or an inclined planet with a north-south (N-S) asymmetric map. For tidally locked planets with thick atmospheres, either of these scenarios entail weather: planets with zero obliquity experience N-S symmetric stellar forcing. North-south asymmetry would therefore suggest stochastic localized features, I.e. weather. However, we find that previous claims of large-amplitude odd modes in Kepler photometry are artefacts of removing planetary transits rather than modelling them. The only reliable claims of odd harmonics remain HAT-P-7b and Kepler-13Ab, for which the third mode amplitude is 6-8 per cent of the planetary flux. Although time-variable albedo maps could in principle explain these odd harmonics, upper-limits on the infrared variability of other hot Jupiters make this scenario unlikely. We recommend further studying the tidal effects of close-in planets on their host stars, as this remains the only plausible hypothesis.

  1. High-precision ground-based photometry of exoplanets

    Directory of Open Access Journals (Sweden)

    de Mooij Ernst J.W.


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

  2. A New Look at Photometry of the Moon (United States)

    Goguen, Jay D.; Stone, T. C.; Kieffer, H. H.; Buratti, B. J.


    We test 2 very different models for light scattering by the lunar regolith: 1) TRLA - a Topographically Rough surface layer comprised of Low Albedo particles, and 2) RTE - a flat surface layer with the published size distribution and optical constants of Apollo soil particles, Mie calculation of the mean particle scattering matrix and rigorous solution of the Radiative Transfer Equation for all orders of scattering (Mishchenko et al 1999, JQRST 63, 409). For a typical lunar highland location (-17.21, 20.01), ROLO photometry (Kieffer & Stone 2005, Astron. J. 129, 2887) shows a distinct difference between the radiances measured before and after full moon (BFM, AFM) at the same 47.5 ± 2.5 degree phase angle, corresponding to incidence angles of 30 and 70 degrees, respectively. The TRLA model requires rms slopes of 34.1 ± 2.6 degrees to reproduce this BFM/AFM radiance difference, similar to previously published results. Analysis of Apollo ALSCC stereo images of in situ lunar regolith (Helfenstein and Shepard 1999, Icarus 141, 107) shows that such large rms slopes pertain to a sub-mm horizontal distance scale. The RTE model also reproduces the same BFM/AFM radiance difference, but as a direct consequence of multiple scattering between particles within the flat (zero topographic roughness) regolith layer. Approximately 80% of the radiance in the RTE model is contributed by photons scattered more than once. We conclude that topographic roughness of the regolith surface and multiple scattering between regolith particles can have a nearly identical effect on this BFM/AFM difference in the lunar radiance. Roughness and multiple scattering are strongly correlated parameters in the sense that any approximations regarding one of them will influence the value deduced for the other. A complete treatment of this work is published in Goguen et al 2010, Icarus 208, 548.

  3. Volumetric Diffuse Optical Tomography for Small Animals Using a CCD-Camera-Based Imaging System

    Directory of Open Access Journals (Sweden)

    Zi-Jing Lin


    Full Text Available We report the feasibility of three-dimensional (3D volumetric diffuse optical tomography for small animal imaging by using a CCD-camera-based imaging system with a newly developed depth compensation algorithm (DCA. Our computer simulations and laboratory phantom studies have demonstrated that the combination of a CCD camera and DCA can significantly improve the accuracy in depth localization and lead to reconstruction of 3D volumetric images. This approach may present great interests for noninvasive 3D localization of an anomaly hidden in tissue, such as a tumor or a stroke lesion, for preclinical small animal models.


    Energy Technology Data Exchange (ETDEWEB)

    Djafer, Djelloul [Unite de Recherche Appliquee en Energies Renouvelables, BP 88, Ghardaiea (Algeria); Irbah, Abdenour, E-mail:, E-mail: [Laboratoire Atmospheres, Milieux, Observations Spatiales (LATMOS), CNRS UMR8190, Universite Paris VI, Pierre et Marie Curie, Universite de Versailles Saint-Quentin-en-Yvelines INSU, 78280 Guyancourt (France)


    Photometric Sun diameter measurement is based on the calculation of the inflection point of the solar limb. In ground measurement, this point is located at a position on the solar limb where the signal-to-noise ratio is very high, which necessitates the appropriate filtering techniques to eliminate the noise while preserving its position. In this paper, we compare the filtering method currently in use to process the CCD solar astrolabe data, the FFTD method widely used, with a different method that we propose. Using the acquired data from the CCD astrolabe at Calern, France during 1997, we can obtain a mean difference of 130 mas in the measured radii.

  5. Processing Method Effect on Sun Diameter Measurement with CCD Solar Astrolabe (United States)

    Djafer, Djelloul; Irbah, Abdenour


    Photometric Sun diameter measurement is based on the calculation of the inflection point of the solar limb. In ground measurement, this point is located at a position on the solar limb where the signal-to-noise ratio is very high, which necessitates the appropriate filtering techniques to eliminate the noise while preserving its position. In this paper, we compare the filtering method currently in use to process the CCD solar astrolabe data, the FFTD method widely used, with a different method that we propose. Using the acquired data from the CCD astrolabe at Calern, France during 1997, we can obtain a mean difference of 130 mas in the measured radii.

  6. Preliminary examination of a CCD camera with a scintillator coated fiber optic plate for neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsubayashi, Masahito E-mail:; Soyama, Kazuhiko


    A charge coupled device (CCD) camera with a scintillator coated fiber optic plate (FOP) was examined for neutron imaging. The FOP coupling and the lens coupling in terms of efficient optical coupling with a CCD, and {sup 6}LiF:ZnS(Ag) and Gd{sub 2}O{sub 2}S(Tb) in terms of light emission efficiency and spatial resolution were discussed. The spatial resolution for each imaging system was obtained as edge spread functions or observations of modulation transfer function charts.

  7. Construction of a photochemical reactor combining a CCD spectrophotometer and a LED radiation source. (United States)

    Gombár, Melinda; Józsa, Éva; Braun, Mihály; Ősz, Katalin


    An inexpensive photoreactor using LED light sources and a fibre-optic CCD spectrophotometer as a detector was built by designing a special cell holder for standard 1.000 cm cuvettes. The use of this device was demonstrated by studying the aqueous photochemical reaction of 2,5-dichloro-1,4-benzoquinone. The developed method combines the highly quantitative data collection of CCD spectrophotometers with the possibility of illuminating the sample independently of the detecting light beam, which is a substantial improvement of the method using diode array spectrophotometers as photoreactors.


    National Aeronautics and Space Administration — This dataset contains photometric measurements of comet 9P/Tempel 1 from images taken with the Medium Resolution CCD Instrument during the approach phase of the Deep...

  9. New Deep HST/ACS Photometry of NGC 1569: Constraining the Evolution of the Strongest Starburst in the Nearby Universe (United States)

    Grocholski, Aaron J.; van der Marel, R. P.; Aloisi, A.; Mack, J.


    Massive starbursts drive the evolution of galaxies at high redshift, but they can only be studied in detail in the nearby Universe where they are much rarer. The dwarf irregular galaxy NGC 1569 has always been considered the closest example of a true starburst, with exceptionally high sustained star formation (SF) over the last Gyr. This recent SF has been extensively constrainted by HST studies that reached to near the presumed magnitude of the tip of the red giant branch (TRGB). These studies could not address the onset of the most ancient SF or the triggering mechanism of the current starburst. Here we present new deep HST ACS/WFC photometry of the resolved stars in NGC 1569 that goes some 4 mag deeper than any previous HST observations. These data allowed us to unequivocally detect and measure the TRGB for the first time and show that NGC 1569 is considerably farther away than previously believed. At ˜3 Mpc it is actually a member of the IC 342 group of galaxies, instead of being a starburst in isolation. In addition to the TRGB, our increased photometric depth also gives access to the fainter red clump and horizontal branch features in the I vs V-I color-magnitude diagram (CMD) of NGC 1569, allowing us to constrain for the first time even the most ancient SFH of this extreme starburst through the use of synthetic CMDs. The area sampled by our ACS/WFC observations is some 25 times larger than in previous HST studies, allowing us to characterize the spatial variations of the SFH, from the central star forming regions of NGC 1569 out into the older and more sparsely populated "halo". The results reveal the evolutionary status of this extreme starburst over cosmic time.

  10. Vi overser hjertepatienter med ondt i livet

    DEFF Research Database (Denmark)

    Ørsted-Rasmussen, Morten; Pedersen, Susanne S.; Zwisler, Ann Dorthe Olsen


    Sundhedsvæsenet har ved en målrettet indsats sikret markant øget overlevelse efter blodprop i hjertet. Men vi risikerer at skylle det hele ud med badevandet, hvis der ikke bliver taget hånd om de psykiske følger i den kroniske fase af sygdommen......Sundhedsvæsenet har ved en målrettet indsats sikret markant øget overlevelse efter blodprop i hjertet. Men vi risikerer at skylle det hele ud med badevandet, hvis der ikke bliver taget hånd om de psykiske følger i den kroniske fase af sygdommen...

  11. Disk-resolved photometry of Asteroid (2867) Steins (United States)

    Spjuth, S.; Jorda, L.; Lamy, P. L.; Keller, H. U.; Li, J.-Y.


    We present a new method to perform disk-resolved photometry in order to investigate the intrinsic photometric properties of the surface of small Solar System bodies. We adopt the standard approach where a shape model is combined with a photometric formalism - in practise the Hapke formalism - to remove the effects of topography and recover the photometric (Hapke) parameters of either the global surface or, in its most elaborated form, the spatial variations of these parameters across the surface. Our method operates in the space of the facets representing the three-dimensional shape of the body, whereas all past analysis have always been performed in the space of the image pixels although they are not intrinsic to the surface of the body. This has the advantage of automatically tracking the same local surface element on a series of images. We first apply our method to images of the nucleus of Comet 9P/Tempel 1 obtained by the High-Resolution Imager (HRI) instrument on board the Deep Impact spacecraft and our derived Hapke parameters are in good agreement with those published by Li et al. (Li, J.-Y. et al. [2007]. Icarus 187, 41-55) within their respective uncertainties. We confirm the presence of an extended region of higher roughness in the southern hemisphere of the nucleus and the higher albedo of the ice-rich regions identified by Sunshine et al. (Sunshine, J.M. et al. [2006]. Science 311, 1453-1455) near the equator. The photometric properties of Asteroid (2867) Steins are then studied from multi-spectral images obtained with the OSIRIS Wide Angle Camera (WAC) on board the Rosetta spacecraft during its flyby on 5 September 2008. Our analysis indicates that the surface is highly porous (∼84%) and that it exhibits both a shadow-hiding opposition effect (SHOE) and probably, a coherent-backscatter opposition effect (CBOE). The single scattering albedo is the highest (SSA = 0.57) ever observed among small bodies visited by spacecrafts. Our modelled roughness

  12. HiPERCAM: a high-speed quintuple-beam CCD camera for the study of rapid variability in the universe (United States)

    Dhillon, Vikram S.; Marsh, Thomas R.; Bezawada, Naidu; Black, Martin; Dixon, Simon; Gamble, Trevor; Henry, David; Kerry, Paul; Littlefair, Stuart; Lunney, David W.; Morris, Timothy; Osborn, James; Wilson, Richard W.


    HiPERCAM is a high-speed camera for the study of rapid variability in the Universe. The project is funded by a ɛ3.5M European Research Council Advanced Grant. HiPERCAM builds on the success of our previous instrument, ULTRACAM, with very significant improvements in performance thanks to the use of the latest technologies. HiPERCAM will use 4 dichroic beamsplitters to image simultaneously in 5 optical channels covering the u'g'r'I'z' bands. Frame rates of over 1000 per second will be achievable using an ESO CCD controller (NGC), with every frame GPS timestamped. The detectors are custom-made, frame-transfer CCDs from e2v, with 4 low noise (2.5e-) outputs, mounted in small thermoelectrically-cooled heads operated at 180 K, resulting in virtually no dark current. The two reddest CCDs will be deep-depletion devices with anti-etaloning, providing high quantum efficiencies across the red part of the spectrum with no fringing. The instrument will also incorporate scintillation noise correction via the conjugate-plane photometry technique. The opto-mechanical chassis will make use of additive manufacturing techniques in metal to make a light-weight, rigid and temperature-invariant structure. First light is expected on the 4.2m William Herschel Telescope on La Palma in 2017 (on which the field of view will be 10' with a 0.3"/pixel scale), with subsequent use planned on the 10.4m Gran Telescopio Canarias on La Palma (on which the field of view will be 4' with a 0.11"/pixel scale) and the 3.5m New Technology Telescope in Chile.

  13. CCD Astrometric Measurements and Historical Data Summary of WDS 12182-4251 (United States)

    Chaudhuri, Anushree; Boyce, Grady


    Precise astrometric coordinates, separation, and position angle of proposed binary system WDS 12182-4251 (DAM 1244) were determined from CCD (charge-coupled device) imaging analysis. The measurements acquired largely align with previously collected data available through databases such as the Washington Double Star (WDS) Catalog. Additionally, the historical data and other information available on this system have been gathered and examined.

  14. Applications in radiation therapy of a scintillating screen viewed by a CCD camera

    NARCIS (Netherlands)

    Schippers, J.M.; Boon, S.N.; van Luijk, P.


    A two-dimensional (2D) dosimetry system has been designed for position-sensitive dose-measurement applications in modem radiation therapy. The system consists of a scintillating screen (Gd2O2S:Tb), observed by a low-noise CCD camera with a long integration time. The system allows reliable and

  15. Subpixel translation of MEMS measured by discrete fourier transform analysis of CCD images

    NARCIS (Netherlands)

    Yamahata, C.; Sarajlic, Edin; Stranczl, M.; Krijnen, Gijsbertus J.M.; Gijs, M.A.M.


    We present a straightforward method for measuring in-plane linear displacements of microelectromechanical systems (MEMS) with subnanometer resolution. The technique is based on Fourier transform analysis of a video recorded with a Charge-Coupled Device (CCD) camera attached to an optical microscope

  16. A graph reader using a CCD image sensor | Seeti | Nigerian Journal ...

    African Journals Online (AJOL)

    Nigerian Journal of Physics. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 20, No 1 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. A graph reader using a CCD image sensor. ML Seeti. Abstract. No Abstract.

  17. Bifunctional lacZ alpha-ccdB genes for selective cloning of PCR products. (United States)

    Gabant, P; Drèze, P L; Van Reeth, T; Szpirer, J; Szpirer, C


    The use of PCR-amplified DNA-fragments is a classical approach to generate recombinant DNA. To facilitate the cloning of PCR products, we have constructed two new pKIL vectors that allow selection of recombinants. The multiple cloning sites (MCS) of these plasmids contain two adjacent Aspel sites and a unique HindII site. Cleavage of these vectors with Aspel produce linearized molecules with a single thymidine nucleotide at the 3' ends allowing TA cloning of Taq-amplified fragments. On the other hand, cleavage with HindII can be used for the cloning of blunt-ended PCR products generated by other DNA polymerases. The LacZ alpha-CcdB fusion protein produced by these plasmids has retained both the CcdB killer activity and the ability to alpha-complement the truncated LacZ delta M15. This bifunctionality allowed us to show that small PCR products (< 1000 bp) that do not disrupt lacZ alpha efficiently do inactivate CcdB, which demonstrates that the CcdB-based selection is well adapted for cloning of PCR products, especially for small size fragments.

  18. On the use of CCD area detectors for high-resolution specular X-ray reflectivity. (United States)

    Fenter, P; Catalano, J G; Park, C; Zhang, Z


    The use and application of charge coupled device (CCD) area detectors for high-resolution specular X-ray reflectivity is discussed. Direct comparison of high-resolution specular X-ray reflectivity data measured with CCD area detectors and traditional X-ray scintillator ('point') detectors demonstrates that the use of CCD detectors leads to a substantial (approximately 30-fold) reduction in data acquisition rates because of the elimination of the need to scan the sample to distinguish signal from background. The angular resolution with a CCD detector is also improved by a factor of approximately 3. The ability to probe the large dynamic range inherent to high-resolution X-ray reflectivity data in the specular reflection geometry was demonstrated with measurements of the orthoclase (001)- and alpha-Al2O3 (012)-water interfaces, with measured reflectivity signals varying by a factor of approximately 10(6) without the use of any beam attenuators. Statistical errors in the reflectivity signal are also derived and directly compared with the repeatability of the measurements.

  19. Single-Electron and Single-Photon Sensitivity with a Silicon Skipper CCD (United States)

    Tiffenberg, Javier; Sofo-Haro, Miguel; Drlica-Wagner, Alex; Essig, Rouven; Guardincerri, Yann; Holland, Steve; Volansky, Tomer; Yu, Tien-Tien


    We have developed ultralow-noise electronics in combination with repetitive, nondestructive readout of a thick, fully depleted charge-coupled device (CCD) to achieve an unprecedented noise level of 0.068 e- rms /pixel . This is the first time that discrete subelectron readout noise has been achieved reproducible over millions of pixels on a stable, large-area detector. This enables the contemporaneous, discrete, and quantized measurement of charge in pixels, irrespective of whether they contain zero electrons or thousands of electrons. Thus, the resulting CCD detector is an ultra-sensitive calorimeter. It is also capable of counting single photons in the optical and near-infrared regime. Implementing this innovative non-destructive readout system has a negligible impact on CCD design and fabrication, and there are nearly immediate scientific applications. As a particle detector, this CCD will have unprecedented sensitivity to low-mass dark matter particles and coherent neutrino-nucleus scattering, while future astronomical applications may include direct imaging and spectroscopy of exoplanets.

  20. Construction of a shortwave near-infrared spectrofluorometer with diode laser source and CCD detection (United States)

    Silzel, John W.; Obremski, Robert J.


    Spectrofluorometers employing xenon arc lamp excitation and photomultiplier tube detectors afford sensitivity over the UV/VIS spectral region for which these instruments were designed, but suffer sensitivity limitations in the short-wave near infrared (NIR) region (800 - 1000 nm) because of their limited source energy and low detector quantum efficiency. To achieve high sensitivity in the NIR region, a 30 mW diode laser source, an imaging spectrograph, and a cryogenically cooled charge-coupled device (CCD) have been combined in a spectrofluorometer specifically designed for use in the NIR region. The diode laser source incorporates integral source filters, optics, and a beam trap, and utilizes a vertical beam geometry which provides an illuminated volume oriented conveniently for the imaging of fluorescence emissions on the entrance slit of the spectrograph. Data is presented which demonstrates that the temporal and spectral stability of the source is equal or superior to that of an arc lamp for solution-phase fluorometry. In addition to spectral information, the CCD detector provides spatial resolution of fluorescence emissions along the vertical path of the excitation beam. An absolute photometric calibration of the CCD detector, and measurement of its read noise, fixed pattern noise, and linear dynamic range is performed using the photon transfer technique of Janesick, et al. Improvement in the instrument performance by more than six decades is demonstrated by measured LOD of NIR dyes using a commercial SLM 4800 instrument and the new diode laser/CCD arrangement. Origin of the present detection limits is discussed.

  1. 3D morphology reconstruction using linear array CCD binocular stereo vision imaging system (United States)

    Pan, Yu; Wang, Jinjiang


    Binocular vision imaging system, which has a small field of view, cannot reconstruct the 3-D shape of the dynamic object. We found a linear array CCD binocular vision imaging system, which uses different calibration and reconstruct methods. On the basis of the binocular vision imaging system, the linear array CCD binocular vision imaging systems which has a wider field of view can reconstruct the 3-D morphology of objects in continuous motion, and the results are accurate. This research mainly introduces the composition and principle of linear array CCD binocular vision imaging system, including the calibration, capture, matching and reconstruction of the imaging system. The system consists of two linear array cameras which were placed in special arrangements and a horizontal moving platform that can pick up objects. The internal and external parameters of the camera are obtained by calibrating in advance. And then using the camera to capture images of moving objects, the results are then matched and 3-D reconstructed. The linear array CCD binocular vision imaging systems can accurately measure the 3-D appearance of moving objects, this essay is of great significance to measure the 3-D morphology of moving objects.

  2. Single-electron and single-photon sensitivity with a silicon Skipper CCD

    Energy Technology Data Exchange (ETDEWEB)

    Tiffenberg, Javier [Fermilab; Sofo-Haro, Miguel [Balseiro Inst., San Carlos de Bariloche; Drlica-Wagner, Alex [Fermilab; Essig, Rouven [YITP, Stony Brook; Guardincerri, Yann [Fermilab; Holland, Steve [LBL, Berkeley; Volansky, Tomer [Tel Aviv U.; Yu, Tien-Tien [CERN


    We have developed a non-destructive readout system that uses a floating-gate amplifier on a thick, fully depleted charge coupled device (CCD) to achieve ultra-low readout noise of 0.068 e- rms/pix. This is the first time that discrete sub-electron readout noise has been achieved reproducibly over millions of pixels on a stable, large-area detector. This allows the precise counting of the number of electrons in each pixel, ranging from pixels with 0 electrons to more than 1500 electrons. The resulting CCD detector is thus an ultra-sensitive calorimeter. It is also capable of counting single photons in the optical and near-infrared regime. Implementing this innovative non-destructive readout system has a negligible impact on CCD design and fabrication, and there are nearly immediate scientific applications. As a particle detector, this CCD will have unprecedented sensitivity to low-mass dark matter particles and coherent neutrino-nucleus scattering, while astronomical applications include future direct imaging and spectroscopy of exoplanets.

  3. A toolkit for the characterization of CCD cameras for transmission electron microscopy

    NARCIS (Netherlands)

    Vulovic, M.; Rieger, B.; Van Vliet, L.J.; Koster, A.J.; Ravelli, R.B.G.


    Charge-coupled devices (CCD) are nowadays commonly utilized in transmission electron microscopy (TEM) for applications in life sciences. Direct access to digitized images has revolutionized the use of electron microscopy, sparking developments such as automated collection of tomographic data, focal

  4. The HST Medium Deep Survey: Steward BVRIJK and FASTTRAK JHK imaging and photometry of faint field galaxies from parallel WF/PC images (United States)

    Mutz, S. B.; Windhorst, R. A.; Ostrander, E. J.; Wittman, D.; Close, L.; McCarthy, D.; Griffiths, R. E.; Neuschaefer, L. W.


    We present ground-based optical (BVRI) and infrared (JHK) photometry for 15 galaxy fields previously observed with HST as part of the Medium-Deep Survey. We use the HST images to determine bulge and disk scale-lengths at 0.1 - 0.2'' FWHM for 70 galaxies in the V and I-bands. We constrain their star-formation history from their ground-based + HST BVRIJHK colors. For galaxies too faint for MMT spectroscopy, we use their BVRIJHK photometry to constrain their redshift-range through Bruzual's (1990) spectral evolution models. Comparing these photometric redshift estimates to spectroscopic redshifts for a brighter subsample, we find acceptable agreement.We conclude this is an efficient way of finding large numbers of field galaxies with z >= 0.8. Using photometric redshift estimates, we extend the Theta -z relation for HST bulges and disks (using world models with q_o = 0.0 - 1.0, see Mutz et al. 1994, ApJL, 434, L055) to z >= 0.8 (V >= 24 mag), beyond most ground-based spectroscopy. We also observed three brighter (17.5 <= I <= 19.0) galaxies with spectroscopic redshifts of z = 0.12 - 0.28 in the K-band with the Steward 90 inch FASTTRAC tip/tilt corrector system. Under seeing conditions of 1.75'' FWHM for a single image of 1.0 second, we derived K-band imaging with FWHM = 1.076'' for a stack of 158 60-second images. We present their V, I, and K-band light profiles, and V-I and I-K color gradients. The V-I and V-K color profiles show that the object at z = 0.12 is likely an early-type galaxy with an exponentially declining star formation parameter mu = 0.4. The object at z = 0.23 is an early-type galaxy with mu = 0.7. The object at z = 0.28 is a late-type disk galaxy seen nearly edge-on. We discuss using FASTTRAC under better seeing conditions and at telescopes with a more optimal ratio of Fried-parameter to mirror-diameter. This work was supported by NASA/HST grants GO-2684-0*-93A from STScI, which is operated by AURA, Inc., under NASA contract NAS5-26555.


    African Journals Online (AJOL)



    May 20, 2016 ... water and air. It affects the growth of flora and fauna which in turn affect human health negatively. Chromium could also bio-accumulate in plants and animals and this becomes ... The sorption kinetic models of Cr (VI) onto the biosorbents were examined with ... bulk density, moisture and ash contents.

  6. 76 FR 60593 - Title VI; Proposed Circular (United States)


    ... for FTA staff to make oral presentations about the two proposed Circulars and allow attendees an... proposed Circular would incorporate lessons learned from triennial reviews, discretionary Title VI... Implementation Plan for Limited English Proficient (LEP) persons now contains a summary of the DOT LEP guidance...

  7. Prospek pengembangan industri perkulitan pada pelita VI


    D. Karyadi


    The leather industry is one of the strong competitive industry, as it comes from renewable natural resources. Therefore, the leather industry has good prospect to develop at the Pelita VI to be the industrial products export competitive. To develop leather industry and leather products should be given closed attention and well managed, especially concerning raw material supply, quality and leather waste treatment.

  8. Resúmenes Presentaciones Orales VI ECAP


    Vargas Arana, Editor Gabriel


    En este artículo se pueden encontrar los resúmenes de las presentaciones orales del VI Ecuentro Científico de la Amazonía Peruana, desarrollado el 27 y 28 de cotubre de 2015 en la ciudad de Iquitos, Perú.

  9. Vi har selv designet naturens love

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose


    ForskerZonenNaturlovene er universelt gyldige i de flestes øjne. De gælder altid, uanset hvad vi tænker. Men dette billede står ikke uimodsagt i videnskabsfilosofien, og der er meget, der tyder på, at det ikke er specielt empirisk korrekt...

  10. Chromium(VI) bioremediation by probiotics. (United States)

    Younan, Soraia; Sakita, Gabriel Z; Albuquerque, Talita R; Keller, Rogéria; Bremer-Neto, Hermann


    Chromium is a common mineral in the earth's crust and can be released into the environment from anthropogenic sources. Intake of hexavalent chromium (Cr(VI)) through drinking water and food causes toxic effects, leading to serious diseases, and is a commonly reported environmental problem. Microorganisms can mitigate or prevent the toxic effects caused by heavy metals in addition to having effective resistance mechanisms to prevent cell damage and bind to these metals, sequestering them from the cell surface and removing them from the body. Species of Lactobacillus, Streptococcus, Bacillus and Bifidobacterium present in the human mouth and gut and in fermented foods have the ability to bind and detoxify some of these substances. This review address the primary topics related to Cr(VI) poisoning in animals and humans and the use of probiotics as a way to mitigate or prevent the toxic effects caused by Cr(VI). Further advances in the genetic knowledge of such microorganisms may lead to discoveries which will clarify the most active microorganisms that act as bioprotectants in bodies exposed to Cr(VI) and are an affordable option for people and animals intoxicated by the oral route. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. 77 FR 52116 - Title VI; Final Circular (United States)


    ... enforcement of Title VI disparate impact regulations, it did not undermine the validity of those regulations... streamlined this process. We have modified the definition of ``disparate impact'' for clarity. We decline to... process reengineering. In response, FTA will review the public engagement plan and its implementation when...

  12. Hvem er vi? Hvem er de?

    DEFF Research Database (Denmark)

    Kryger, Niels


    Kommentaren tager afsæt i initiativer i de pædagogiske faglige foreninger i Europa EERA) og i Norden (NERA) og argumenterer for at det er forpligtelse for os som nordiske og europæiske pædagogiske forskere at gå op imod de stadigt mere ekskluderende vi-konstruktioner, som er blevet formuleret i for...

  13. A comparative study on the observation of spontaneous nystagmus with Frenzel glasses and an infrared CCD camera. (United States)

    Baba, Shunkichi; Fukumoto, Akiko; Aoyagi, Mio; Koizumi, Yasuo; Ikezono, Tetsuo; Yagi, Toshiaki


    To compare the usefulness of a CCD camera with infrared illumination (IR-CCD camera) over Frenzel glasses (F Glasses) for the observation of spontaneous nystagmus, the incidence and direction of nystagmus, and the frequency, amplitude and slow phase of spontaneous nystagmus. One hundred vertiginous patients, fifty-three females and forty-seven males participated in this study. Before undergoing routine neurotological examination, their eye movements were recorded by electronystagmogram (ENG) in conjunction with observations of eye movements under F glasses and through an IR-CCD camera. The data was collected from patients who exhibited spontaneous nystagmus either under F glasses or the IR-CCD camera. Thirty-three patients showed spontaneous nystagmus under F glasses. On the other hand, under the IR-CCD camera, all patients examined exhibited spontaneous nystagmus. The frequency of nystagmus was not significantly different between these two systems. However, the amplitude and slow phase velocity exhibited significantly larger values under the IR-CCD camera in patients with spontaneous nystagmus both under the IR-CCD camera and F glasses. From these observations and evidence, the IR-CCD camera can be recommended as a more useful system and powerful tool for neurotological examination than F glasses.

  14. Laboratory precision photometry test results for the High-speed Imaging Photometer for Occultations (HIPO) (United States)

    Zangari, A. M.; Dunham, E.; Mandushev, G.; Person, M. J.; Collins, P.; Bida, T.; Taylor, B.; Zoonematkermani, S.


    We present the results of several laboratory precision photometry tests using the High-speed Imaging Photometer for Occultations (HIPO), one of seven first generation instruments of the Stratospheric Observatory For Infrared Astronomy (SOFIA). Using artificial stars illuminated by an integrating sphere, we have tested the stability of the photometry in the laboratory against variations in chip temperature, controller temperature, and power supply temperature. We find that changes in the controller temperature and the chip temperature correlate with millimag-level changes in differential photometry and sub-pixel changes in the centroid location of the artificial stars. We find that data can be averaged for up to 10 minutes and 0.1 millimag during times of temperature fluctuations if a single amplifier is used to take data without effecting the results. We make operating recommendations based on the test results and discuss the suitability of HIPO for research beyond occultations, such as exoplanet transits.

  15. A configurable distributed high-performance computing framework for satellite's TDI-CCD imaging simulation (United States)

    Xue, Bo; Mao, Bingjing; Chen, Xiaomei; Ni, Guoqiang


    This paper renders a configurable distributed high performance computing(HPC) framework for TDI-CCD imaging simulation. It uses strategy pattern to adapt multi-algorithms. Thus, this framework help to decrease the simulation time with low expense. Imaging simulation for TDI-CCD mounted on satellite contains four processes: 1) atmosphere leads degradation, 2) optical system leads degradation, 3) electronic system of TDI-CCD leads degradation and re-sampling process, 4) data integration. Process 1) to 3) utilize diversity data-intensity algorithms such as FFT, convolution and LaGrange Interpol etc., which requires powerful CPU. Even uses Intel Xeon X5550 processor, regular series process method takes more than 30 hours for a simulation whose result image size is 1500 * 1462. With literature study, there isn't any mature distributing HPC framework in this field. Here we developed a distribute computing framework for TDI-CCD imaging simulation, which is based on WCF[1], uses Client/Server (C/S) layer and invokes the free CPU resources in LAN. The server pushes the process 1) to 3) tasks to those free computing capacity. Ultimately we rendered the HPC in low cost. In the computing experiment with 4 symmetric nodes and 1 server , this framework reduced about 74% simulation time. Adding more asymmetric nodes to the computing network, the time decreased namely. In conclusion, this framework could provide unlimited computation capacity in condition that the network and task management server are affordable. And this is the brand new HPC solution for TDI-CCD imaging simulation and similar applications.

  16. Development of a CCD-based pyrometer for surface temperature measurement of casting billets (United States)

    Zhang, Yuzhong; Lang, Xianli; Hu, Zhenwei; Shu, Shuangbao


    In order to achieve high accuracy and good stability of temperature measurement results, an online vision-based temperature field measurement system for continuous casting billets is developed instead of the conventional single-point radiation pyrometer in this paper. This system is a hybrid temperature measurement system which consists of a monochrome array CCD camera with high resolution and a single spot colorimetric thermometer simultaneously. In this system, a narrow-band spectrum radiation temperature measurement model is established for the optical CCD-based pyrometer system, and the non-uniformity of the temperature field measurement due to the inter-element sensitivity deviations of the CCD-array detector and photometric distortion caused by the vignetting in the optical system is analyzed in detail and compensated. Furthermore, in order to eliminate the temperature fluctuation caused by the stripped iron oxide scale on billets, a temperature field reconstruction approach, which took full advantage of the high resolution characteristic of CCD and the distribution character of the surface temperature field of billets, is introduced in this system. Meanwhile, based on the narrow band spectral thermometry theory, the spot temperature measured by the colorimetric thermometer is used to correct the temperature field measured by the CCD camera on-line so as to reduce the temperature measurement error caused by the inconclusive absolute emissivity of different grades of steel and the interference of industrial dust. Currently, the system has been successfully applied and verified in some continuous casting production lines. Industrial trials indicate that the system could effectively eliminate false temperature variation caused by striped iron oxide scale and provide information about changes of processing parameters in the continuous casting production line in real time.

  17. [A quickly atmospheric correction method for HJ-1 CCD with deep blue algorithm]. (United States)

    Wang, Zhong-Ting; Wang, Hong-Mei; Li, Qing; Zhao, Shao-Hua; Li, Shen-Shen; Chen, Liang-Fu


    In the present, for the characteristic of HJ-1 CCD camera, after receiving aerosol optical depth (AOD) from deep blue algorithm which was developed by Hsu et al. assisted by MODerate-resolution imaging spectroradiometer (MODIS) surface reflectance database, bidirectional reflectance distribution function (BRDF) correction with Kernel-Driven Model, and the calculation of viewing geometry with auxiliary data, a new atmospheric correction method of HJ-1 CCD was developed which can be used over vegetation, soil and so on. And, when the CCD data is processed to correct atmospheric influence, with look up table (LUT) and bilinear interpolation, atmospheric correction of HJ-1 CCD is completed quickly by grid calculation of atmospheric parameters and matrix operations of interface define language (IDL). The experiment over China North Plain on July 3rd, 2012 shows that by our method, the atmospheric influence was corrected well and quickly (one CCD image of 1 GB can be corrected in eight minutes), and the reflectance after correction over vegetation and soil was close to the spectrum of vegetation and soil. The comparison with MODIS reflectance product shows that for the advantage of high resolution, the corrected reflectance image of HJ-1 is finer than that of MODIS, and the correlation coefficient of the reflectance over typical surface is greater than 0.9. Error analysis shows that the recognition error of aerosol type leads to 0. 05 absolute error of surface reflectance in near infrared band, which is larger than that in visual bands, and the 0. 02 error of reflectance database leads to 0.01 absolute error of surface reflectance of atmospheric correction in green and red bands.

  18. Jonckheere Double Star Photometry – Part VIII: Sextans (United States)

    Knapp, Wilfried


    If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part of them with magnitudes obviously far too bright. This report covers the Jonckheere objects in the constellation Sextans. One image per object was taken with V-filter to allow for visual magnitude measurement by differential photometry. All objects were additionally checked for common proper motion and a good part of the objects qualify indeed as potential CPM pairs.

  19. A transit timing analysis with combined ground- and space-based photometry

    Directory of Open Access Journals (Sweden)

    Raetz St.


    The CoRoT satellite looks back on six years of high precision photometry of a very high number of stars. Thousands of transiting events are detected from which 27 were confirmed to be transiting planets so far. In my research I search and analyze TTVs in the CoRoT sample and combine the unprecedented precision of the light curves with ground-based follow-up photometry. Because CoRoT can observe transiting planets only for a maximum duration of 150 days the ground-based follow-up can help to refine the ephemeris. Here we present first examples.

  20. Cloning and expression of a Vi mimotope of Salmonella enterica ...

    African Journals Online (AJOL)



    Sep 15, 2009 ... A recombinant His-Vi protein of Salmonella enterica serovar Typhi was successfully constructed and cloned into an expression vector ... recombinant protein can be used to detect specific anti-Vi antibody produced by typhoid patients. Overall, the His-Vi ... E-mail: Tel.:603-. 79676607.

  1. Bioreduction of Cr (VI) by potent novel chromate resistant alkaliphilic ...

    African Journals Online (AJOL)

    Isolation of Cr (VI) resistant alkaliphilic bacteria from sediment and water samples collected from Wadi Natrun hypersaline Soda lakes (located in northern Egypt), resulted in isolation of several alkaliphilic bacterial strains that can tolerate up to 2.94 g/l of Cr (VI) in alkaline medium. However, with increasing Cr (VI) ...

  2. [An Improved DDV Method to Retrieve AOT for HJ CCD Image in Typical Mountainous Areas]. (United States)

    Zhao, Zhi-qiang; Li, Ai-nong; Bian, Jin-hu; Huang, Cheng-quan


    Domestic HJ CCD imaging applications in environment and disaster monitoring and prediction has great potential. But, HJ CCD image lack of Mid-Nir band can not directly retrieve Aerosol Optical Thickness (AOT) by the traditional Dark Dense Vegetation (DDV) method, and the mountain AOT changes in space-time dramatically affected by the mountain environment, which reduces the accuracy of atmospheric correction. Based on wide distribution of mountainous dark dense forest, the red band histogram threshold method was introduced to identify the mountainous DDV pixels. Subsequently, the AOT of DDV pixels were retrieved by lookup table constructed by 6S radiative transfer model with assumption of constant ratio between surface reflectance in red and blue bands, and then were interpolated to whole image. MODIS aerosol product and the retrieved AOT by the proposed algorithm had very good consistency in spatial distribution, and HJ CCD image was more suitable for the remote sensing monitoring of aerosol in mountain areas, which had higher spatial resolution. Their fitting curve of scatterplot was y = 0.828 6x-0.01 and R2 was 0.984 3 respectively. Which indicate the improved DDV method can effectively retrieve AOT, and its precision can satisfy the atmospheric correction and terrain radiation correction for Hj CCD image in mountainous areas. The improvement of traditional DDV method can effectively solve the insufficient information problem of the HJ CCD image which have only visible light and near infrared band, when solving radiative transfer equation. Meanwhile, the improved method fully considered the influence of mountainous terrain environment. It lays a solid foundation for the HJ CCD image atmospheric correction in the mountainous areas, and offers the possibility for its automated processing. In addition, the red band histogram threshold method was better than NDVI method to identify mountain DDV pixels. And, the lookup table and ratio between surface reflectance

  3. Development of low-noise CCD drive electronics for the world space observatory ultraviolet spectrograph subsystem (United States)

    Salter, Mike; Clapp, Matthew; King, James; Morse, Tom; Mihalcea, Ionut; Waltham, Nick; Hayes-Thakore, Chris


    World Space Observatory Ultraviolet (WSO-UV) is a major Russian-led international collaboration to develop a large space-borne 1.7 m Ritchey-Chrétien telescope and instrumentation to study the universe at ultraviolet wavelengths between 115 nm and 320 nm, exceeding the current capabilities of ground-based instruments. The WSO Ultraviolet Spectrograph subsystem (WUVS) is led by the Institute of Astronomy of the Russian Academy of Sciences and consists of two high resolution spectrographs covering the Far-UV range of 115-176 nm and the Near-UV range of 174-310 nm, and a long-slit spectrograph covering the wavelength range of 115-305 nm. The custom-designed CCD sensors and cryostat assemblies are being provided by e2v technologies (UK). STFC RAL Space is providing the Camera Electronics Boxes (CEBs) which house the CCD drive electronics for each of the three WUVS channels. This paper presents the results of the detailed characterisation of the WUVS CCD drive electronics. The electronics include a novel high-performance video channel design that utilises Digital Correlated Double Sampling (DCDS) to enable low-noise readout of the CCD at a range of pixel frequencies, including a baseline requirement of less than 3 electrons rms readout noise for the combined CCD and electronics system at a readout rate of 50 kpixels/s. These results illustrate the performance of this new video architecture as part of a wider electronics sub-system that is designed for use in the space environment. In addition to the DCDS video channels, the CEB provides all the bias voltages and clocking waveforms required to operate the CCD and the system is fully programmable via a primary and redundant SpaceWire interface. The development of the CEB electronics design has undergone critical design review and the results presented were obtained using the engineering-grade electronics box. A variety of parameters and tests are included ranging from general system metrics, such as the power and mass

  4. The hard X-ray response of the XIS-CCD for Astro-E: qualification of the X-ray CCD detector

    CERN Document Server

    Nishiuchi, M; Awaki, H; Tsuru, T; Sakano, M; Hamaguchi, K; Murakami, H; Tsunemi, H; Hayashida, K; Kitamoto, S; Miyata, E; Dotani, T; Ozaki, M; Bautz, M; Doty, J; Kissel, S; Foster, R; Ricker, G


    We report on the hard X-ray response of the CCD detector for the X-ray imaging spectrometer (XIS), to be launched on the next Japanese X-ray Astronomical Satellite, ASTRO-E, in February 2000. XIS is prepared by an international team, comprised of MIT (USA), ISAS, Osaka University and Kyoto University (JAPAN). We have evaluated the X-ray response of the XIS in its high-energy band (1.5-10 keV). Data from the fluorescent line emission of Al, Cl, Ti, Ni, Fe, Zn, Se were used to construct the response function of the CCD detectors. Details of the response function - including the energy-scale, linearity, energy resolution, quantum efficiency -, are given as a function of incident X-ray energy. We find that the tail component of high-energy photopeaks are produced by events with incomplete charge collection. We also conclude that the size of the charge clouds can be estimated using the shapes of the tail components.

  5. Noget vi kan tro på

    DEFF Research Database (Denmark)

    Olsen, Jan Brødslev


    Situationen er alvorlig. Verden står over for enorme udfordringer med pres på naturressourcer, klima, befolkningsvækst, flygtninge og konflikter. Det er svært at se, hvordan disse problemer kan håndteres inden for den nuværende menneskelige bevidstheds rammer. Vi må derfor foretage et bevidstheds......Situationen er alvorlig. Verden står over for enorme udfordringer med pres på naturressourcer, klima, befolkningsvækst, flygtninge og konflikter. Det er svært at se, hvordan disse problemer kan håndteres inden for den nuværende menneskelige bevidstheds rammer. Vi må derfor foretage et...

  6. Hvad skal vi med Trump-satire?

    DEFF Research Database (Denmark)

    Møller, Mette


    Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?......Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?...


    Directory of Open Access Journals (Sweden)



    Full Text Available Cloud point extraction (CPE was used to extract uranium (VI from an aqueous solution in acetate media. The methodology used is based on the formation of uranyl-ionic liquid (I complexes and uranyl-D2EHPA soluble in a micellar phase of non-ionic surfactant (Triton X-100. The uranium (VI complexes are then extracted into the surfactant-rich phase at ambient temperature. The ionic liquid (IL used as a chelating agent was synthesized and characterized in this study. It is composed of N-butyl N’-triethoxy methyl imidazolium cation and diethylhexylphosphate (D2EHPA-H as anion. The effect of the IL on the extraction efficiency was studied in presence and in absence of IL’s cation in acetate medium.

  8. Application of a finite size of the charge cloud shape generated by an X-ray photon inside the CCD

    CERN Document Server

    Tsunemi, H; Miyata, E


    A mesh experiment enables us to specify the X-ray landing position on a charge-coupled device (CCD) with subpixel resolution. By this experiment, we find that the final charge cloud shape generated by Ti-K X-ray photons (4.5 keV) in the CCD is about 1.5x1.1 mu m sup 2 (standard deviation). An X-ray photon photoabsorbed in the CCD generates a number of electrons, forming an X-ray event. It becomes up to a 4-pixel-split event since the pixel size of the CCD used (12 mu m square pixel) is bigger than the charge cloud size. Using the mesh experiment, we can determine the X-ray landing position on the CCD. In this way, we can compare the estimated X-ray landing position with the actual landing position on the CCD. Employing the charge cloud shape, we can improve the position resolution of the X-ray CCD by referring to the X-ray event pattern. We find that the position accuracy of our method is about 1.0 mu m. We discuss our method, comparing it with the charge centroid method.

  9. VizieR Online Data Catalog: Photometry of EXors from Asiago plates (Jurdana-Sepic+, 2017) (United States)

    Jurdana-Sepic, R.; Munari, U.; Antoniucci, S.; Giannini, T.; Li Causi, G.; Lorenzetti, D.


    File table1 contains the BVRI photometry of NY, V1143, V1118 in Orion from the plates of the Asiago Observatory, Italy. Columns provide date and central UT of any exposure, plate emulsion, the adopted filter, the telescope, the plate number, and the magnitude derived for the three sources with the estimated error. See notes for further details. (2 data files).

  10. Photographic photometry of 16000 galaxies on ESO blue and red survey plates

    NARCIS (Netherlands)

    Lauberts, A.; Valentijn, E. A.


    An ongoing photometric survey of 16,000 galaxies on ESO red and blue plates is described. The galaxies of the ESO/Uppsala Catalog (Lauberts, 1982) are being PDS scanned, and the results are combined with existing photometry and supplementary observational data obtained at the 1-m ESO telescope to

  11. High-precision photometry by telescope defocusing - I. The transiting planetary system WASP-5

    DEFF Research Database (Denmark)

    Southworth, J.; Hinse, T. C.; Jørgensen, U. G.


    We present high-precision photometry of two transit events of the extrasolar planetary system WASP-5, obtained with the Danish 1.54-m telescope at European Southern Obseratory La Silla. In order to minimize both random and flat-fielding errors, we defocused the telescope so its point spread...

  12. Time-series Analysis of Broadband Photometry of Neptune from K2

    NARCIS (Netherlands)

    Rowe, Jason F.; Gaulme, Patrick; Lissauer, Jack J.; Marley, Mark S.; Simon, Amy A.; Hammel, Heidi B.; Silva Aguirre, Víctor; Barclay, Thomas; Benomar, Othman; Boumier, Patrick; Caldwell, Douglas A.; Casewell, Sarah L.; Chaplin, William J.; Colón, Knicole D.; Corsaro, Enrico; Davies, G. R.; Fortney, Jonathan J.; Garcia, Rafael A.; Gizis, John E.; Haas, Michael R.; Mosser, Benot; Schmider, Francois Xavier


    We report here on our search for excess power in photometry of Neptune collected by the K2 mission that may be due to intrinsic global oscillations of the planet Neptune. To conduct this search, we developed new methods to correct for instrumental effects such as intrapixel variability and gain

  13. ASAS-SN photometry of the Galactic nova TCP J17394608-2457555 (United States)

    Strader, J.; Chomiuk, L.; Brown, J. S.; Stanek, K. Z.; Holoien, T. W.-S.; Kochanek, C. S.; Shields, J.; Thompson, T. A.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, S.; Bose, S.; Chen, P.; Brimacombe, J.


    We report ASAS-SN photometry of the Galactic nova TCP J17394608-2457555 (CBAT; ATel #10366). ASAS-SN recovered the source with a first detection (V=14.9) on Apr 21.43 UT, 17 days before the discovery by K. Itagaki.


    National Aeronautics and Space Administration — This data set contains aperture photometry of known transiting planet systems GJ 436, HAT-P-4, HAT-P-7, TrES-2, TrES-3, and WASP-3 derived from radiance calibrated,...

  15. Corneal hysteresis in mucopolysaccharidosis I and VI. (United States)

    Fahnehjelm, Kristina Teär; Chen, Enping; Winiarski, Jacek


    High intraocular pressure (IOP) and glaucoma are often suspected in patients with mucopolysaccharidosis (MPS). To determine corneal hysteresis (CH) and IOP in children with mucopolysaccharidosis I-Hurler (MPS I-H) and MPS VI. Clinical measurements with ocular response analyzer (ORA). In seven patients, five with MPS I-H treated with stem cell transplantation (SCT), and two with MPS VI, one treated with SCT and the other with enzyme therapy, the IOP was examined with ORA. Ocular response analyzer measurements were made at a median age of 8.7 years in the patients with MPS I-H and at a median age of 9.3 years in the patients with MPS VI. Earlier measurements had raised suspicion of high IOP in one patient. The ORA showed an increased CH and a falsely high IOP values in all 14 eyes. The recalculated IOPs were normal in all 14 eyes. Mild to severe corneal opacities were present in all 14 eyes. Optic disc areas, borders and cupping were clinically normal in the 12 of 14 eyes that were possible to examine. Severe corneal opacities hampered optic disc evaluation in the older patient with MPS VI. Three eyes in two patients had normal thickness of the retinal nerve fibre layer measured with scanning laser polarimetry with corneal compensation (GDx VCC). No patient was diagnosed or treated for glaucoma. The IOPs are often falsely high because of an increased resistance of the cornea and correlate to the extent of corneal clouding. In this small, cross-sectional study, it appears that corneal resistance is directly correlated with corneal clouding, although a longitudinal study that evaluates resistance as the cornea clears with treatment would provide more direct evidence that corneal deposits are directly related to resistance. A correct measured IOP can avoid unnecessary medical or surgical hypotensive treatment. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  16. Prospek pengembangan industri perkulitan pada pelita VI

    Directory of Open Access Journals (Sweden)

    D Karyadi


    Full Text Available The leather industry is one of the strong competitive industry, as it comes from renewable natural resources. Therefore, the leather industry has good prospect to develop at the Pelita VI to be the industrial products export competitive. To develop leather industry and leather products should be given closed attention and well managed, especially concerning raw material supply, quality and leather waste treatment.

  17. Brayton Isotope Power System. Phase I. (Ground demonstration system) Configuration Control Document (CCD)

    Energy Technology Data Exchange (ETDEWEB)


    The configuration control document (CCD) defines the BIPS-GDS configuration. The GDS configuration is similar to a conceptual flight system design, referred to as the BIPS-FS, which is discussed in App. I. The BIPS is being developed by ERDA as a 500 to 2000 W(e), 7-y life, space power system utilizing a closed Brayton cycle gas turbine engine to convert thermal energy (from an isotope heat source) to electrical energy at a net efficiency exceeding 25 percent. The CCD relates to Phase I of an ERDA Program to qualify a dynamic system for launch in the early 1980's. Phase I is a 35-month effort to provide an FS conceptual design and GDS design, fabrication, and test. The baseline is a 7-year life, 450-pound, 4800 W(t), 1300 W(e) system which will use two multihundred watt (MHW) isotope heat sources being developed.

  18. Continuity of Care Document (CCD) Enables Delivery of Medication Histories to the Primary Care Clinician (United States)

    Simonaitis, Linas; Belsito, Anne; Cravens, Gary; Shen, Changyu; Overhage, J. Marc


    Introduction: The goal of the Enhanced Medication History (EMH) project is to provide medication histories to ambulatory primary care practices in the Indiana Network for Patient Care. Methods: Medications were aggregated from three different sources of pharmacy data (Medicaid, SureScripts, and the county health system of Indianapolis). Dispensing events were assembled into the Continuity of Care Document (CCD), and presented to clinicians as RxNorm Clinical Drugs. Results: The EMH project completed 46 weeks of operation in a community health center in Indianapolis. Medication Histories were generated for 10498 office visits for 4449 distinct patients. Seven (of nine) attending physicians responded to a written survey and found the Medication Histories useful (3.9±0.4 on a scale of 1 to 5). Conclusion: Implementation of the EMH project demonstrated the successful use (as well as the challenging aspects) of the CCD and the RxNorm terminology in the outpatient clinical setting. PMID:21347078

  19. BVRI Standardization of the CCD Photometric System of Sobaeksan Optical Astronomy Observatory

    Directory of Open Access Journals (Sweden)

    Jang Hae Jeong


    Full Text Available A total of 792 CCD images of V523 Cas were obtained on four nights of Jan. 2003 with the BVRI CCD photometric system attached to a 61cm reflector of Sobaeksan Optical Astronomy Observatory (SOAO. The 17 standard stars in the images were used to establish transformation relations between our BVRI system and the standard Johnson-Cousins BVRI system. We derived the tentative equations of transformation between two photometric systems as follows; V = v-0.0689(B-V+0.0063 B-V = 1.3197(b-v-0.1733 V-R = 0.9210(v-r-0.1309 R-I = 0.8892(r-i-0.1055. Using these equations standard V magnitudes and their color indexes (B-V, V-R, R-I for 57 stars in the field of the image were determined.

  20. BVR Standardization of the CCD Photometric System of Chungbuk National University Observatory

    Directory of Open Access Journals (Sweden)

    Jang-Hae Jeong


    Full Text Available BVR observations for 52 standard stars were performed using the 1-m reflecter with 2K CCD System of Chungbuk National University Observatory(CBNUO in 2008. We obtained 1,322 CCD images to establish a correlation between our bvr system and the standard Johnson-Cousins BVR system. We derived the tentative equations of transformation between then as follows; V = v-0.0303(B-V+0.0466 B-V = 1.3475(b-v-0.0251 V-R = 1.0641(v-r-0.0125 Using these equations the magnitudes in V, B-V, and V-R for 197 stars were obtained.

  1. 800 x 800 charge-coupled device /CCD/ camera for the Galileo Jupiter Orbiter mission (United States)

    Clary, M. C.; Klaasen, K. P.; Snyder, L. M.; Wang, P. K.


    During January 1982 the NASA space transportation system will launch a Galileo spacecraft composed of an orbiting bus and an atmospheric entry probe to arrive at the planet Jupiter in July 1985. A prime element of the orbiter's scientific instrument payload will be a new generation slow-scan planetary imaging system based on a newly developed 800 x 800 charge-coupled device (CCD) image sensor. Following Jupiter orbit insertion, the single, narrow-angle, CCD camera, designated the Solid State Imaging (SSI) Subsystem, will operate for 20 months as the orbiter makes repeated encounters with Jupiter and its Galilean Satellites. During this period the SSI will acquire 40,000 images of Jupiter's atmosphere and the surfaces of the Galilean Satellites. This paper describes the SSI, its operational modes, and science objectives.

  2. Puesta en marcha de un microdensitómetro automático basado en CCD (United States)

    Calderón, J. H.; Bustos Fierro, I. H.

    We present the commisioning of a CCD-based microdensitometer intended to perform astrometric measurements of photographic plates. The work done consisted in the installation of a CCD camera, the modification of the motion system, the construction of a new illumination device, the adaptation of the electronics, and the development of software. The instrument is intended to be used for the astrometric measurement mainly of plates of the Astrographic Catalog and Carte du Ciel collections from Córdoba Observatory. In this phase of the project we counted with the collaboration of the Instituto Provincial de Enseñanza Media No 59, 25 de Mayo, Cruz Alta (Province of Córdoba). The origin and importance of such collaboration is commented.

  3. [Atmospheric correction method for HJ-1 CCD imagery over waters based on radiative transfer model]. (United States)

    Xu, Hua; Gu, Xing-Fa; Li, Zheng-Qiang; Li, Li; Chen, Xing-Feng


    Atmospheric correction is a bottleneck in quantitative application of Chinese satellites HJ-1 data to remote sensing of water color. According to the characteristics of CCD sensors, the present paper made use of air-water coupled radiative transfer model to work out the look-up table (LUT) of atmospheric corrected parameters, and thereafter developed pixel-by-pixel atmospheric correction method over waters accomplishing the water-leaving remote sensing reflectance with accessorial meteorological input. The paper validates the HJ-1 CCD retrievals with MODIS and in-situ results. It was found that the accuracy in blue and green bands is good. However, the accuracy in red or NIR bands is much worse than blue or green ones. It was also demonstrated that the aerosol model is a sensitive factor to the atmospheric correction accuracy.

  4. Comparison of a CCD and an APS for soft X-ray diffraction (United States)

    Stewart, Graeme; Bates, R.; Blue, A.; Clark, A.; Dhesi, S. S.; Maneuski, D.; Marchal, J.; Steadman, P.; Tartoni, N.; Turchetta, R.


    We compare a new CMOS Active Pixel Sensor (APS) to a Princeton Instruments PIXIS-XO: 2048B Charge Coupled Device (CCD) with soft X-rays tested in a synchrotron beam line at the Diamond Light Source (DLS). Despite CCDs being established in the field of scientific imaging, APS are an innovative technology that offers advantages over CCDs. These include faster readout, higher operational temperature, in-pixel electronics for advanced image processing and reduced manufacturing cost. The APS employed was the Vanilla sensor designed by the MI3 collaboration and funded by an RCUK Basic technology grant. This sensor has 520 x 520 square pixels, of size 25 μm on each side. The sensor can operate at a full frame readout of up to 20 Hz. The sensor had been back-thinned, to the epitaxial layer. This was the first time that a back-thinned APS had been demonstrated at a beam line at DLS. In the synchrotron experiment soft X-rays with an energy of approximately 708 eV were used to produce a diffraction pattern from a permalloy sample. The pattern was imaged at a range of integration times with both sensors. The CCD had to be operated at a temperature of -55°C whereas the Vanilla was operated over a temperature range from 20°C to -10°C. We show that the APS detector can operate with frame rates up to two hundred times faster than the CCD, without excessive degradation of image quality. The signal to noise of the APS is shown to be the same as that of the CCD at identical integration times and the response is shown to be linear, with no charge blooming effects. The experiment has allowed a direct comparison of back thinned APS and CCDs in a real soft x-ray synchrotron experiment.

  5. Collony Collapse Disorder (CCD). A review of the possible Factors and Agents involved


    Espinosa del Alba, Laura


    Póster Colony collapse disorder is a complex phenomenon that affects managed honey bee (Apis mellifera) colonies, whose main trait is a rapid loss of adult worker bees. Adult worker bees are responsible of the majority of the hive tasks, so their absence means shortly after the collapse and dead of the colony. CCD has been reported mainly from USA, but also from Europe.

  6. Data Reduction and Control Software for Meteor Observing Stations Based on CCD Video Systems (United States)

    Madiedo, J. M.; Trigo-Rodriguez, J. M.; Lyytinen, E.


    The SPanish Meteor Network (SPMN) is performing a continuous monitoring of meteor activity over Spain and neighbouring countries. The huge amount of data obtained by the 25 video observing stations that this network is currently operating made it necessary to develop new software packages to accomplish some tasks, such as data reduction and remote operation of autonomous systems based on high-sensitivity CCD video devices. The main characteristics of this software are described here.

  7. Smear correction of highly variable, frame-transfer CCD images with application to polarimetry. (United States)

    Iglesias, Francisco A; Feller, Alex; Nagaraju, Krishnappa


    Image smear, produced by the shutterless operation of frame-transfer CCD detectors, can be detrimental for many imaging applications. Existing algorithms used to numerically remove smear do not contemplate cases where intensity levels change considerably between consecutive frame exposures. In this report, we reformulate the smearing model to include specific variations of the sensor illumination. The corresponding desmearing expression and its noise properties are also presented and demonstrated in the context of fast imaging polarimetry.

  8. Versatile ultrafast pump-probe imaging with high sensitivity CCD camera


    Pezeril, Thomas; Klieber, Christoph; Temnov, Vasily; Huntzinger, Jean-Roch; Anane, Abdelmadjid


    International audience; A powerful imaging technique based on femtosecond time-resolved measurements with a high dynamic range, commercial CCD camera is presented. Ultrafast phenomena induced by a femtosecond laser pump are visualized through the lock-in type acquisition of images recorded by a femtosecond laser probe. This technique allows time-resolved measurements of laser excited phenomena at multiple probe wavelengths (spectrometer mode) or conventional imaging of the sample surface (ima...

  9. CCD measurements of double and multiple stars at NAO Rozhen. III

    Directory of Open Access Journals (Sweden)

    Cvetković Z.


    Full Text Available Using the 2-m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 55 multiple stars were carried out during one night, December 16/17. 2006. This is the third series of CCD measurements of double and multiple stars carried out at Rozhen. In the paper we present the results for the position angle and separation for 49 multiple stars (67 pairs which could be measured. .

  10. CCD measurements of double and multiple stars at NAO Rozhen. IV

    Directory of Open Access Journals (Sweden)

    Cvetković Zorica


    Full Text Available Using the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen observations of 30 double or multiple stars were carried out during two half nights on July 20 and 21, 2009. This is the fourth series of measurements of CCD frames of double and multiple stars obtained at Rozhen. In this paper we present the results for the position angle and separation for 23 double and 5 multiple stars (35 pairs which could have been measured.

  11. CCD Measurements of Double and Multiple Stars at NAO Rozhen. IV

    Directory of Open Access Journals (Sweden)

    Boeva, S.


    Full Text Available Using the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen observations of 30 double or multiple stars were carried out during two half nights on July 20and 21, 2009. This is the fourth series of measurements of CCD frames of double and multiple stars obtained at Rozhen. In this paper we present the results for the position angle and separation for 23 double and 5 multiple stars (35 pairs which could have been measured.

  12. Miniature CCD X-Ray Imaging Camera Technology Final Report CRADA No. TC-773-94

    Energy Technology Data Exchange (ETDEWEB)

    Conder, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mummolo, F. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    The goal of the project was to develop a compact, large active area, high spatial resolution, high dynamic range, charge-coupled device (CCD) camera to replace film for digital imaging of visible light, ultraviolet radiation, and soft to penetrating X-rays. The camera head and controller needed to be capable of operation within a vacuum environment and small enough to be fielded within the small vacuum target chambers at LLNL.

  13. A toolkit for the characterization of CCD cameras for transmission electron microscopy. (United States)

    Vulovic, M; Rieger, B; van Vliet, L J; Koster, A J; Ravelli, R B G


    Charge-coupled devices (CCD) are nowadays commonly utilized in transmission electron microscopy (TEM) for applications in life sciences. Direct access to digitized images has revolutionized the use of electron microscopy, sparking developments such as automated collection of tomographic data, focal series, random conical tilt pairs and ultralarge single-particle data sets. Nevertheless, for ultrahigh-resolution work photographic plates are often still preferred. In the ideal case, the quality of the recorded image of a vitrified biological sample would solely be determined by the counting statistics of the limited electron dose the sample can withstand before beam-induced alterations dominate. Unfortunately, the image is degraded by the non-ideal point-spread function of the detector, as a result of a scintillator coupled by fibre optics to a CCD, and the addition of several inherent noise components. Different detector manufacturers provide different types of figures of merit when advertising the quality of their detector. It is hard for most laboratories to verify whether all of the anticipated specifications are met. In this report, a set of algorithms is presented to characterize on-axis slow-scan large-area CCD-based TEM detectors. These tools have been added to a publicly available image-processing toolbox for MATLAB. Three in-house CCD cameras were carefully characterized, yielding, among others, statistics for hot and bad pixels, the modulation transfer function, the conversion factor, the effective gain and the detective quantum efficiency. These statistics will aid data-collection strategy programs and provide prior information for quantitative imaging. The relative performance of the characterized detectors is discussed and a comparison is made with similar detectors that are used in the field of X-ray crystallography.

  14. A faint-object grism spectrograph with multiple slits and CCD detector (United States)

    Geary, John C.; Huchra, John P.; Latham, David W.


    A high-efficiency spectrograph for research on faint astronomical objects has been successfully built and is in regular use on the Multiple-Mirror Telescope (MMT). It is equipped with a motorized multi-slit mechanism to allow simultaneous observations of several objects. The combination of high throughput, multiple object capability, and low-noise CCD detector has allowed routine work to be extended to objects of V magnitude 23 and fainter.

  15. 3D measurement for archeological artifact using CCD camera and line laser beam (United States)

    Yokoyama, Hiroshi; Hatano, Katsuhiro; Chikatsu, Hirofumi


    In the compilation of archival records for archeological artifacts, true ortho-graphic drawings of these artifacts have to be drawn by the archaeologists themselves or part- timers, taking a great deal of time, labor and skill. For saving the labor, the authors have developed ortho projection system using CCD camera. 3D measurement system using ortho projection system are described in this paper. Finally, it demonstrates wireframe model for jomon-pottery by using this system.

  16. Mucopolissacaridose tipo VI: relato de caso

    Directory of Open Access Journals (Sweden)

    Lais Orosco Bialon Santana


    Full Text Available Introdução: As mucopolissacaridoses são erros inatos do metabolismo de depósito lisossomal subclassificadas segundo a enzima deficiente. A arilsulfatase B (ARSB, responsável por degradar os glicosaminoglicanos (GAGs, que atuam no tecido conjuntivo, é deficiente na mucopolissacaridose tipo VI (MP VI. A MP VI tem clínica variável, sem anormalidades ao nascimento, evidenciando-se progressivamente ao acúmulo de GAGs. O diagnóstico se faz pela redução da atividade da ARSB ou da mutação genética. A principal causa de óbito é insuficiência cardíaca, ocorrendo na segunda ou terceira década de vida. Relato de Caso: Masculino, 4 anos, portador de MP VI, há 3 dias com febre e sinais flogísticos em sítio de acesso central, colocado para reposição enzimática, com flutuação e saída de material purulento. Ultrassom evidenciou coleção laminar e borramento de planos gordurosos. Ecocardiograma demonstra hipertensão pulmonar discreta decorrente de prolapso valvar mitral com refluxo discreto, além de endocardite da valva mitral. Optou-se por retirada cirúrgica do dispositivo e administração de vancomicina e amicacina. Durante internação, evoluiu bem, sem complicações pós operatórias. Conclusão: A MP VI têm inteligência preservada, baixa estatura e alterações osteomusculares, como no caso relatado. Não há correlação entre a gravidade clínica e a atividade residual enzimática. Dificuldade respiratória pode levar a hipóxia crônica, hipertensão pulmonar e insuficiência cardíaca congestiva. Das alterações cardíacas, encontramos valvulopatias, insuficiência cardíaca e hipertensão pulmonar, observadas no caso. O tratamento se faz com transplante de células-tronco hematopoiéticas e terapia de reposição enzimática.

  17. Dynamic Mapping of Rice Growth Parameters Using HJ-1 CCD Time Series Data

    Directory of Open Access Journals (Sweden)

    Jing Wang


    Full Text Available The high temporal resolution (4-day charge-coupled device (CCD cameras onboard small environment and disaster monitoring and forecasting satellites (HJ-1A/B with 30 m spatial resolution and large swath (700 km have substantially increased the availability of regional clear sky optical remote sensing data. For the application of dynamic mapping of rice growth parameters, leaf area index (LAI and aboveground biomass (AGB were considered as plant growth indicators. The HJ-1 CCD-derived vegetation indices (VIs showed robust relationships with rice growth parameters. Cumulative VIs showed strong performance for the estimation of total dry AGB. The cross-validation coefficient of determination ( R C V 2 was increased by using two machine learning methods, i.e., a back propagation neural network (BPNN and a support vector machine (SVM compared with traditional regression equations of LAI retrieval. The LAI inversion accuracy was further improved by dividing the rice growth period into before and after heading stages. This study demonstrated that continuous rice growth monitoring over time and space at field level can be implemented effectively with HJ-1 CCD 10-day composite data using a combination of proper VIs and regression models.

  18. Precise CCD positions of Himalia using Gaia DR1 in 2015-2016 (United States)

    Peng, H. W.; Peng, Q. Y.; Wang, N.


    In order to obtain high-precision CCD positions of Himalia, the sixth Jovian satellite, a total of 598 CCD observations have been obtained during the years 2015-2016. The observations were made by using the 2.4 and 1 m telescopes administered by Yunnan Observatories over 27 nights. Several factors that would influence the positional precision of Himalia were analysed, including the reference star catalogue used, the geometric distortion and the phase effect. By taking advantage of its unprecedented positional precision, the recently released catalogue Gaia Data Release 1 was chosen to match reference stars in the CCD frames of both Himalia and open clusters, which were observed for deriving the geometric distortion. The latest version of sofa library was used to calculate the positions of reference stars. The theoretical positions of Himalia were retrieved from the Jet Propulsion Laboratory Horizons System that includes the satellite ephemeris JUP300, while the positions of Jupiter were based on the planetary ephemeris DE431. Our results showed that the means of observed minus computed (O - C) residuals are 0.071 and -0.001 arcsec in right ascension and declination, respectively. Their standard deviations are estimated at about 0.03 arcsec in each direction.

  19. Atmospheric correction of HJ-1 CCD imagery over turbid lake waters. (United States)

    Zhang, Minwei; Tang, Junwu; Dong, Qing; Duan, Hongtao; Shen, Qian


    We have presented an atmospheric correction algorithm for HJ-1 CCD imagery over Lakes Taihu and Chaohu with highly turbid waters. The Rayleigh scattering radiance (Lr) is calculated using the hyperspectral Lr with a wavelength interval 1nm. The hyperspectral Lr is interpolated from Lr in the central wavelengths of MODIS bands, which are converted from the band response-averaged Lr calculated using the Rayleigh look up tables (LUTs) in SeaDAS6.1. The scattering radiance due to aerosol (La) is interpolated from La at MODIS band 869nm, which is derived from MODIS imagery using a shortwave infrared atmospheric correction scheme. The accuracy of the atmospheric correction algorithm is firstly evaluated by comparing the CCD measured remote sensing reflectance (Rrs) with MODIS measurements, which are validated by the in situ data. The CCD measured Rrs is further validated by the in situ data for a total of 30 observation stations within ± 1h time window of satellite overpass and field measurements. The validation shows the mean relative errors about 0.341, 0.259, 0.293 and 0.803 at blue, green, red and near infrared bands.

  20. Cooling System for a Frame-Store PN-CCD Detector for Low Background Application

    CERN Document Server

    Pereira, H; Santos Silva, P; Kuster, M; Lang, P


    The astroparticle physics experiment CERN Axion Solar Telescope (CAST) aims to detect hypothetical axions or axion-like particles produced in the Sun by the Primakoff process. A Large Hadron Collider (LHC) prototype superconducting dipole magnet provides a 9 T transverse magnetic field for the conversion of axions into detectable X-ray photons. These photons are detected with an X-ray telescope and a novel type of frame-store CCD detector built from radio-pure materials, installed in the optics focal plane. A novel type of cooling system has been designed and built based on krypton-filled cryogenic heat pipes, made out of oxygen-free radiopure copper, and a Stirling cryocooler as cold source. The heat pipes provide an efficient thermal coupling between the cryocooler and the CCD which is kept at stable temperatures between 150 and 230 K within an accuracy of 0.1 K. A graded-Z radiation shield, also serving as a gas cold-trap operated at 120 K, is implemented to reduce the surface contamination of the CCD wind...

  1. Heat dissipation schemes in QCLs monitored by CCD thermoreflectance (Conference Presentation) (United States)

    Pierscinski, Kamil; Pierścińska, Dorota; Morawiec, Magdalena; Gutowski, Piotr; Karbownik, Piotr; Serebrennikova, Olga; Bugajski, Maciej


    In this paper we present the development of the instrumentation for accurate evaluation of the thermal characteristics of quantum cascade lasers based on CCD thermoreflectance (CCD TR). This method allows rapid thermal characterization of QCLs, as the registration of high-resolution map of the whole device facet lasts only several seconds. The capabilities of the CCD TR are used to study temperature dissipation schemes in different designs of QCLs. We report on the investigation of thermal performance of QCLs developed at the Institute of Electron Technology, with an emphasis on the influence of different material system, processing technology and device designs. We investigate and compare AlInAs/InGaAs/InP QCLs (lattice matched and strain compensated) of different architectures, i.e., double trench and buried heterostructure (BH) in terms of thermal management. Experimental results are in very good agreement with numerical predictions of heat dissipation in various device constructions. Numerical model is based on FEM model solved by commercial software package. The model assumes anisotropic thermal conductivity in the AR layers as well as the temperature dependence of thermal conductivities of all materials in the project. We have observed experimentally improvement of thermal properties of devices based on InP materials, especially for buried heterostructure type. The use of buried heterostructure enhanced the lateral heat dissipation from the active region of QCLs. The BH structure and epilayer-down bonding help dissipate the heat generated from active core of the QCL.

  2. Functional Expression of Aquaporin-2 Tagged with Photoconvertible Fluorescent Protein in mpkCCD Cells

    Directory of Open Access Journals (Sweden)

    Kay-Pong Yip


    Full Text Available Background: Vasopressin induced trafficking of aquaporin-2 (AQP2 containing vesicles has been studied in kidney cell lines using conventional fluorescent proteins as tags. However, trafficking of fluorescent tagged AQP2, which resembles the vectorial translocation of native AQP2 from cytoplasm to apical membrane has not been demonstrated at real time. Using a photoconvertible fluorescent protein tag on AQP2 might allow the simultaneous tracking of two separate populations of AQP2 vesicle after subcellular local photoconversion. Methods: A spacer was used to link a photoconvertible fluorescent protein (mEos2 to the amino-terminus of AQP2. The DNA constructs were expressed in mpkCCD cells. The trafficking of chimeric protein was visualized with high speed confocal microscopy in 4 dimensions. Results: Chimeric AQP2 expressed in mpkCCD cell conferred osmotic water permeability to the cells. Subcellular photoconversion with a 405 nm laser pulse converted green chimeras to red chimeras locally. Forskolin stimulation triggered chimeric AQP2 to translocate from acidic organelles to apical plasma membrane. By serendipity, the rate of apical accumulation was found to increase when mEos2 was tagged to the carboxyl-terminus in at least one of the AQP2 molecules within the tetramer. Conclusion: Functional photoconvertible chimeric AQP2 was successfully expressed in mpkCCD cells, in which forskolin induced apical trafficking and accumulation of chimeric AQP2. The proof-of-concept to monitor two populations of AQP2 vesicle simultaneously was demonstrated.

  3. Evaluation of diagnostic ability of CCD digital radiography in the detection of incipient dental caries

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Wan; Lee, Byung Do [Wonkwang University College of Medicine, Iksan (Korea, Republic of)


    The purpose of this experiment was to evaluate the diagnostic ability of a CCD-based digital system (CDX-2000HQ) in the detection of incipient dental caries. 93 extracted human teeth with sound proximal surfaces and interproximal artificial cavities were radiographed using 4 imaging methods. Automatically processed No.2 Insight film (Eastman Kodak Co., U.S.A.) was used for conventional radiography, scanned images of conventional radiograms for indirect digital radiography were used. For the direct digital radiography, the CDX-2000HQ CCD system (Biomedisys Co. Korea) was used. The subtraction images were made from two direct digital images by Sunny program in the CDX-2000HQ system. Two radiologists and three endodontists examined the presence of lesions using a five-point confidence scale and compared the diagnostic ability by ROC (Receiver Operating Characteristic) analysis and one way ANOVA test. The mean ROC areas of conventional radiography, indirect digital radiography, direct digital radiography, and digital subtraction radiography were 0.9093, 0.9102, 0.9184, and 0.9056, respectively. The diagnostic ability of direct digital radiography was better than the other imaging modalities, but there were no statistical differences among these imaging modalities (p>0.05). These results indicate that new CCD-based digital systems (CDX-2000HQ) have the potential to serve as an alternative to conventional radiography in the detection of incipient dental caries.

  4. An Overview on Production and Applications of Ferrate(VI

    Directory of Open Access Journals (Sweden)



    Full Text Available Context Coagulation, chemical oxidation and disinfection are essential processes in water and waste treatment. A chemical that can be applied for all the above mentioned purposes is ferrate(VI. Although there are many studies about ferrate(VI, no comprehensive review paper can be found about ferrate(VI from production to applications. The aim of this study was to review ferrate(VI production, measurement, stability and utilization in water and wastewater treatment. Evidence Acquisition In acidic conditions, the oxidation and reduction capacity of ferrate(VI is superior to all currently utilized oxidizers and disinfectants in water and wastewater treatment. New researches have provided the technology of using ferrate(VI for coagulation, chemical oxidation and disinfection of water and wastewater in a reactor simultaneously, which can reduce the size of water and wastewater treatment plants and increase the treatment efficiency. Results Despite the existence of these technologies, there is no full-scale application of ferrate(VI in the water and wastewater industry which it is due to difficulties associated with I, the lack of adequate researches that have demonstrated its capabilities and advantages over the existing water and wastewater treatment methods; ii, the instability of ferrate(VI depending on its method of preparation, and iii, the relatively low yield of ferrate(VI. Conclusions To solve the above mentioned difficulties, fundamental study most be carried out to discover the novel methods of ferrate(VI production, focusing on increasing the product stability and the production yield.

  5. Cramer-Rao lower bound optimization of an EM-CCD-based scintillation gamma camera. (United States)

    Korevaar, Marc A N; Goorden, Marlies C; Beekman, Freek J


    Scintillation gamma cameras based on low-noise electron multiplication (EM-)CCDs can reach high spatial resolutions. For further improvement of these gamma cameras, more insight is needed into how various parameters that characterize these devices influence their performance. Here, we use the Cramer-Rao lower bound (CRLB) to investigate the sensitivity of the energy and spatial resolution of an EM-CCD-based gamma camera to several parameters. The gamma camera setup consists of a 3 mm thick CsI(Tl) scintillator optically coupled by a fiber optic plate to the E2V CCD97 EM-CCD. For this setup, the position and energy of incoming gamma photons are determined with a maximum-likelihood detection algorithm. To serve as the basis for the CRLB calculations, accurate models for the depth-dependent scintillation light distribution are derived and combined with a previously validated statistical response model for the EM-CCD. The sensitivity of the lower bounds for energy and spatial resolution to the EM gain and the depth-of-interaction (DOI) are calculated and compared to experimentally obtained values. Furthermore, calculations of the influence of the number of detected optical photons and noise sources in the image area on the energy and spatial resolution are presented. Trends predicted by CRLB calculations agree with experiments, although experimental values for spatial and energy resolution are typically a factor of 1.5 above the calculated lower bounds. Calculations and experiments both show that an intermediate EM gain setting results in the best possible spatial or energy resolution and that the spatial resolution of the gamma camera degrades rapidly as a function of the DOI. Furthermore, calculations suggest that a large improvement in gamma camera performance is achieved by an increase in the number of detected photons or a reduction of noise in the image area. A large noise reduction, as is possible with a new generation of EM-CCD electronics, may improve the

  6. Response surface methodological approach for the optimization of adsorption process in the removal of Cr(VI) ions by Cu2(OH)2CO3 nanoparticles (United States)

    Srivastava, Varsha; Sharma, Y. C.; Sillanpää, Mika


    Cu2(OH)2CO3 nanoparticles were synthesized and characterized by XRD, TEM, SEM and ATR-FTIR. SEM suggested the porous nature of nanoparticles. BET surface area of nanoparticles was measured to be 87 m2 g-1. Cu2(OH)2CO3 nanoparticles were used as adsorbent for the removal of Cr(VI) ions from aqueous solutions and wastewater of the printing press. The central composite design (CCD) of the response surface methodology was employed to optimize important adsorption parameters viz. initial Cr(VI) concentration, pH and dose. Analysis of variance (ANOVA) of the quadratic model suggested that experimental data were excellently fitted to the quadratic model. Optimum conditions for approximately 99% removal of Cr(VI) from synthetic wastewater were determined to be pH 6.5, initial concentration of 550 mg/L, adsorbent dose 0.69 g. The kinetic data for Cr(VI) adsorption were best fitted to the pseudo second order model. The Langmuir adsorption capacity of the adsorbent was determined as 87.72 mg/g. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. Desorption study confirms its reusability up to four adsorption-desorption cycles. Cu2(OH)2CO3 nanoparticles also showed efficient removal in presence of anions like SO42-, PO43-, NO32- and Cl-. Findings of the present study suggest that Cu2(OH)2CO3 is a suitable adsorbent material for the removal of Cr(VI) from aqueous solutions and wastewater.

  7. A multiple CCD X-ray detector and its first operation with synchrotron radiation X-ray beam

    CERN Document Server

    Suzuki, M; Kumasaka, T; Sato, K; Toyokawa, H; Aries, I F; Jerram, P A; Ueki, T


    A 4x4 array structure of 16 identical CCD X-ray detector modules, called the multiple CCD X-ray detector system (MCCDX), was submitted to its first synchrotron radiation experiment at the protein crystallography station of the RIKEN beamline (BL45XU) at the SPring-8 facility. An X-ray diffraction pattern of cholesterol powder was specifically taken in order to investigate the overall system performance.

  8. High time resolution CCD camera with X-ray image intensifier for SPring-8 BL40XU

    CERN Document Server

    Oka, T; Yagi, N


    SPring-8 BL40XU is designed to use high flux X-ray for small angle X-ray scattering and multi purpose. The flux at the experimental hutch is about 1 x 10 sup 1 sup 5 photons/sec at 12.4 KeV, which is larger 2 approx 3 figures than other beamlines at SPring-8. To utilize the high flux X-ray efficiently, new high-speed detector is needed. Therefore, a high frame rate CCD camera C7770 (Hamamatsu) and a new 6-inch X-ray image intensifier V5445P (Hamamatsu) were developed for BL40XU. The CCD camera has three CCD chips to increase the readout speed. Three identical images are created by a prism system in the CCD camera and projected onto the three chips. The pixel number of the CCD is 640 x 480 and the frame rate is 291 frames/sec. Reduction of the number of horizontal lines leads to a faster frame rate up to a few thousands. The combination of the CCD and with an X-ray shutter also leads to faster discrete data acquisition. (author)

  9. A comparison of film and 3 digital imaging systems for natural dental caries detection: CCD, CMOS, PSP and film

    Energy Technology Data Exchange (ETDEWEB)

    Han, Won Jeong [Dankook University College of Medicine, Seoul (Korea, Republic of)


    To evaluate the diagnostic accuracy of occlusal and proximal caries detection using CCD, CMOS, PSP and film system. 32 occlusal and 30 proximal tooth surfaces were radiographed under standardized conditions using 3 digital systems; CCD (CDX-2000HQ, Biomedysis Co., Seoul, Korea), CMOS (Schick, Schick Inc., Long Island, USA), PSP (Digora FMX, Orion Co./Soredex, Helsinki, Finland) and 1 film system (Kodak Insight, Eastman Kodak, Rochester, USA). 5 observers examined the radiographs for occlusal and proximal caries using a 5-point confidence scale. The presence of caries was validated histologically and radiographically. Diagnostic accuracy was evaluated using ROC curve areas (AZ). Analysis using ROC curves revealed the area under each curve which indicated a diagnostic accuracy. For occlusal caries, Kodak Insight film had an Az of 0.765, CCD one of 0.730, CMOS one of 0.742 and PSP one of 0.735. For proximal caries, Kodak Insight film had an Az of 0.833, CCD one of 0.832, CMOS one of 0.828 and PSP one of 0.868. No statistically significant difference was noted between any of the imaging modalities. CCD, CMOS, PSP and film performed equally well in the detection of occlusal and proximal dental caries. CCD, CMOS and PSP-based digital images provided a level of diagnostic performance comparable to Kodak Insight film.

  10. Farvel til globaliseringen som vi kendte den

    DEFF Research Database (Denmark)

    Böss, Michael


    Vi er endt med en krise, som rækker langt ud over det globale monetære system, fordi den ideologiske ortodoksi, der skabte den, har ført til udflytning af millioner af arbejdspladser, tæring af nationalstaternes sammenhængskraft og overgreb på naturen. Kronikken refererer bl.a. til John Maynard...... Keynes og en artikel af økonomen Robert Skidelsky i The American Prospect. Udgivelsesdato: 12. januar 2009...



    Svendsen, Nana Lysbo; Birksholm, Sarah Schlander; Rosendahl, Rasmus; Albrechtsen, Nadja Loran


    This study consists of a rhetorical analysis of how the Danish Broadcasting Corporation argues for the compulsory license fee in their campaign video: ’Licens er noget vi giver til hinanden’. On the assumption that a visual product can argue on equal terms with the spoken language, the paper will look at the specific visual tools that are used in the argumentation and the portrayal of the concept of public service and the license fee. In extension to this the paper will examine if the vid...

  12. Discovery of a Probable Nova in M81 and Photometry of Three M81 Novae (United States)

    Hornoch, K.; Errmann, R.; Carlisle, Ch.; Vaduvescu, O.


    We report the discovery of a probable nova in M81 on a co-added 1600-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.6" seeing on 2015 Jan.

  13. Oral–Facial–Digital Syndrome type VI with self mutilations

    Directory of Open Access Journals (Sweden)

    Rabah M. Shawky


    Full Text Available We report the case of a 2.5 year old female, 2nd in order of birth of 1st cousin consanguineous marriage, with the typical features of Oral–Facial–Digital Syndrome type VI (OFDS VI including midline pseudo cleft upper lip, sublingual nodule, molar tooth sign by MRI brain, bilateral mesoaxial polydactyly (hexadactyly, and developmental delay. The patient had self mutilations which was not reported before in OFDS VI except once.

  14. Environmental survey of Region VI, Haltenbanken, 2009; Miljoeundersoekelse i Region VI, Haltenbanken, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Holm, May-Helen; Cochrane, Sabine; Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen


    There has been an environmental investigation in Region VI Halten Bank. This report presents the results of the chemical and biological assays performed on samples from a total of 316 stations in 16 fields and 15 regional stations. A status of environmental conditions in the region is given at the end of the report. (AG)

  15. Environmental Survey in Region VI, Haltenbanken, 2009. Summary report; Miljoeundersoekelse i Region VI, Haltenbanken, 2009. Sammendragsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen


    An environmental survey of Region VI, Haltenbanken, has been carried out. This report presents the results from the analyses carried out on samples from a total of 316 stations at 16 fields and 15 regional stations. A status of the environmental conditions in the region is given at the end of the report. (Author)

  16. Fremtidens lavenergibyggeri - kan vi gøre som vi plejer?

    DEFF Research Database (Denmark)

    Larsen, Tine Steen


    Stramninger af kravene til energiforbruget i vores boliger medfører stor fokus på energiberegningen, men erfaringer fra lavenergiboliger opført i dag viser, at vi, for at sikre succes for fremtidens boliger, også skal inddrage dokumentation af indeklimaet og forbedre samarbejdet mellem arkitekter...

  17. Vi lider af prætraumatisk stress

    DEFF Research Database (Denmark)

    Hansen, Brian Benjamin


    Vi lider af prætraumatisk stress. Vi vil nemlig nå det hele og presser konstant nye aftaler ind i vores kalender. Det eneste, der hjælper, er at ’gøre intet’ – men kan man overhovedet det? Udgivelsesdato: 30.09.09......Vi lider af prætraumatisk stress. Vi vil nemlig nå det hele og presser konstant nye aftaler ind i vores kalender. Det eneste, der hjælper, er at ’gøre intet’ – men kan man overhovedet det? Udgivelsesdato: 30.09.09...

  18. Behaviour of chromium(VI) in stormwater soil infiltration systems

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Ingvertsen, Simon T.; Jensen, Marina B.


    The ability of stormwater infiltration systems to retain Cr(VI) was tested by applying a synthetic stormwater runoff solution with a neutral pH and high Cr(VI) concentrations to four intact soil columns excavated from two roadside infiltration swales in Germany. Inlet flow rates mimicked normal (10......, while under extreme rain events approximately 20% of Cr(VI) was retained. In both cases effluent concentrations of Cr(VI) would exceed the threshold value of 3.4 mu g/L if the infiltrated water were introduced to freshwater environments. More knowledge on the composition of the stormwater runoff...

  19. Remediation of Cr(VI) in solution using vitamin C*


    LIU, Yong; Xu, Xin-hua; He, Ping


    The effectiveness of vitamin C in treating Cr(VI)-contaminated water is being evaluated. Cr(VI) is an identified pollutant of some soils and groundwater. Vitamin C, an important biological reductant in humans and animals, can be used to transform Cr(VI) to essentially nontoxic Cr(III). The removal efficiency was 89% when the mass concentration of vitamin C was 80 mg/L in 60 min, and nearly 100% Cr(VI) was removed when the mass concentration was 100 mg/L. Our data demonstrated that the removal...

  20. Heterogeneity of collagens in rabbit cornea: type VI collagen

    National Research Council Canada - National Science Library

    Cintron, C; Hong, BS


    .... These physical characteristics, together with the susceptibility of these polypeptides to collagenase and their amino acid composition, identified the high molecular weight aggregate as type VI collagen...

  1. Jonckheere Double Star Photometry – Part IX: Sagitta (United States)

    Knapp, Wilfried


    If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part with magnitudes obviously far too bright. This report covers a part of the Jonckheere objects in the constellation Sagitta including a check if physical by means of UCAC5 proper motion data. In most cases only one image per object is taken for differential photometry as even a single image based measurement is better than the currently often given mere estimation. As by-product a new CPM candidate pair was discovered and as appendix the UCAC5 proper motion data quality was counter-checked with GAIA DR1 (TGAS).

  2. Photometric study of selected cataclysmic variables II. Time-series photometry of nine systems. (United States)

    Papadaki, C.; Boffin, H. M. J.; Stanishev, V.; Boumis, P.; Akras, S.; Sterken, C.


    We present time-series photometry of nine cataclysmic variables: EI UMa, V844 Her, V751 Cyg, V516 Cyg, GZ Cnc, TY Psc, V1315 Aql, ASAS J002511+1217.2, V1315 Aql and LN UMa. The observations were conducted at various observatories, covering 170 hours and comprising 7,850 data points in total. For the majority of targets we confirm previously reported periodicities and for some of them we give, for the first time through photometry, their underlying spectroscopic orbital period. For those dwarf-nova systems which we observed during both quiescence and outburst, the increase in brightness was accompanied by a decrease in the level of flickering. For the eclipsing system V1315 Aql we have covered 9 eclipses, and obtained a refined orbital ephemeris. We find that, during this long baseline of observations, no change in the orbital period of this system has occurred. V1315 Aql also shows eclipses of variable depth.

  3. Multi-Epoch Photometry of Luminous Stars in M31 and M33 (United States)

    Martin, John C.; Humphreys, Roberta M.


    Typically, the characteristics of supernovae and supernovae impostor progenitors are pieced together post-hoc from disparate sources after the event. Regular monitoring of luminous stars in nearby galaxies provides a more detailed and uniform source of information about those stars leading up to a significant event.We present Johnson/Cousins BVRI photometry from the first four years (2012 - 2016) of a targeted ground-based monitoring campaign of luminous stars in M31 and M33 including: likely supernovae and supernovae impostor progenitors, luminous infrared sources, classical LBVs, and warm and cool hypergiants. We have constructed a pipeline capable of quickly mining our images for photometry of additional targets.The survey will continue to image most of M31 and M33 on an annual basis for the foreseeable future.

  4. Late Neanderthals at Jarama VI (central Iberia)? (United States)

    Kehl, Martin; Burow, Christoph; Hilgers, Alexandra; Navazo, Marta; Pastoors, Andreas; Weniger, Gerd-Christian; Wood, Rachel; Jordá Pardo, Jesús F.


    Previous geochronological and archaeological studies on the rock shelter Jarama VI suggested a late survival of Neanderthals in central Iberia and the presence of lithic assemblages of Early Upper Paleolithic affinity. New data on granulometry, mineralogical composition, geochemical fingerprints and micromorphology of the sequence corroborate the previous notion that the archaeological units JVI.2.1 to JVI.2.3 are slackwater deposits of superfloods, which did not experience significant post-depositional changes, whereas the artifact-rich units JVI.3 and JVI.1 mainly received sediment inputs by sheetwash and cave spall. New AMS radiocarbon measurements on three samples of cut-marked bone using the ultrafiltration technique yielded ages close to, or beyond, the limit of radiocarbon dating at ca. 50 14C ka BP, and hence suggest much higher antiquity than assumed previously. Furthermore, elevated temperature post-IR IRSL luminescence measurements on K feldspars yielded burial ages for subunits JVI.2.2 and JVI.2.3 between 50 and 60 ka. Finally, our reappraisal of the stone industry strongly suggests that the whole sequence is of Mousterian affinity. In conclusion, Jarama VI most probably does not document a late survival of Neanderthals nor an Early Upper Paleolithic occupation in central Iberia, but rather indicates an occupation breakdown after the Middle Paleolithic.

  5. Investigation of uranium (VI) adsorption by polypyrrole. (United States)

    Abdi, S; Nasiri, M; Mesbahi, A; Khani, M H


    The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride as an oxidant in the aqueous solution. The effect of various surfactants on the synthesized polymers and their performance as the uranium adsorbent were investigated. Adsorbent properties were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The effect of different parameters such as pH, contact time, initial metal ion concentrations, adsorbent dose, and the temperature was investigated in the batch system for uranium adsorption process. It has been illustrated that the adsorption equilibrium time is 7min. The results showed that the Freundlich model had the best agreement and the maximum adsorption capacity of polypyrrole for uranium (VI) was determined 87.72mg/g from Langmuir isotherm. In addition, the mentioned adsorption process was fast and the kinetic data were fitted to the Pseudo first and second order models. The adsorption kinetic data followed the pseudo-second-order kinetic model. Moreover, the thermodynamic parameters ΔG(0), ΔH(0) and ΔS(0) showed that the uranium adsorption process by polypyrrole was endothermic and spontaneous. Copyright © 2017. Published by Elsevier B.V.

  6. On-Line High Dose-Rate Gamma Ray Irradiation Test of the CCD/CMOS Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)


    In this paper, test results of gamma ray irradiation to CCD/CMOS cameras are described. From the CAMS (containment atmospheric monitoring system) data of Fukushima Dai-ichi nuclear power plant station, we found out that the gamma ray dose-rate when the hydrogen explosion occurred in nuclear reactors 1{approx}3 is about 160 Gy/h. If assumed that the emergency response robot for the management of severe accident of the nuclear power plant has been sent into the reactor area to grasp the inside situation of reactor building and to take precautionary measures against releasing radioactive materials, the CCD/CMOS cameras, which are loaded with the robot, serve as eye of the emergency response robot. In the case of the Japanese Quince robot system, which was sent to carry out investigating the unit 2 reactor building refueling floor situation, 7 CCD/CMOS cameras are used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. In the preceding assumptions, a major problem which arises when dealing with CCD/CMOS cameras in the severe accident situations of the nuclear power plant is the presence of high dose-rate gamma irradiation fields. In the case of the DBA (design basis accident) situations of the nuclear power plant, in order to use a CCD/CMOS camera as an ad-hoc monitoring unit in the vicinity of high radioactivity structures and components of the nuclear reactor area, a robust survivability of this camera in such intense gamma-radiation fields therefore should be verified. The CCD/CMOS cameras of various types were gamma irradiated at a

  7. Interaction of monosaccharides and related compounds with oxocations of Mo(VI), W(VI) and U(VI) studied by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Geraldes, C.F.G.C.; Castro, M.M.C.A.; Saraiva, M.E.; Aureliano, M.; Dias, B.A.


    Proton, /sup 13/C and /sup 31/P nuclear magnetic resonance spectroscopy has been used to study the complexation of Mo(VI), W(VI) and U(VI) oxocations with various aldoses, cyclic polyols and ribose-5-phosphate in aqueous solution. The aldoses D-mannose, D-lyxose and D-ribose form tridentate complexes with Mo(VI) and W(VI) at pH similarly ordered 5, via the 1,2,3-hydroxyl groups, which are cis to each other in these sugars. Other aldoses, like D-arabinose, D-glucose, D-xylose and D-galactose form weaker bidentate complexes with those ions because they can only use the 1 and 3-cis hydroxyl groups in metal binding. These bidentate interactions also take place in the binding of U(VI) to D-mannose and D-ribose, at pH similarly ordered 10. However, sugars having 1,3,5-hydroxyl groups in the cis position do not form stable chelates with these oxocations, possibly due to steric crowding. In the case of ribose-5-phosphate, the phosphate group is the exclusive binding site for the three oxocations, except for U(VI) at very basic pH (pH > 10), where the hydroxyl groups also interact with UO/sub 2//sup 2 +/.

  8. APASS Landolt-Sloan BVgri photometry of Rave stars. I. Data, effective temperatures, and reddenings

    Energy Technology Data Exchange (ETDEWEB)

    Munari, U.; Siviero, A. [INAF Osservatorio Astronomico di Padova, I-36012 Asiago (VI) (Italy); Henden, A. [AAVSO, Cambridge, MA (United States); Frigo, A. [ANS Collaboration, c/o Astronomical Observatory, Padova (Italy); Zwitter, T. [Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana (Slovenia); Bienaymé, O.; Siebert, A. [Observatoire Astronomique, Université de Strasbourg, CNRS, 11 rue de l' université F-67000 Strasbourg (France); Bland-Hawthorn, J. [Sydney Institute for Astronomy, University of Sydney, NSW 2006 (Australia); Boeche, C.; Grebel, E. K. [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, D-69120 Heidelberg (Germany); Freeman, K. C. [Mount Stromlo Observatory, RSAA, Australian National University, Weston Creek, Canberra, ACT 2611 (Australia); Gibson, B. K. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston, PR1 2HE (United Kingdom); Gilmore, G.; Kordopatis, G. [Institute of Astronomy, Cambridge University, Madingley Road, Cambridge CB3 0HA (United Kingdom); Helmi, A. [Kapteyn Astronomical Institute, University of Groningen, PO Box 800, 9700 AV Groningen (Netherlands); Levine, S. E. [Lowell Observatory, Flagstaff, AZ (United States); Navarro, J. F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 5C2 (Canada); Parker, Q. A.; Reid, W. [Department of Physics and Astronomy, Macquarie University, NSW 2109 (Australia); Seabroke, G. M. [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, RH5 6NT (United Kingdom); and others


    We provide AAVSO Photometric All-Sky Survey (APASS) photometry in the Landolt BV and Sloan g'r'i' bands for all 425,743 stars included in the fourth RAVE Data Release. The internal accuracy of the APASS photometry of RAVE stars, expressed as the error of the mean of data obtained and separately calibrated over a median of four distinct observing epochs and distributed between 2009 and 2013, is 0.013, 0.012, 0.012, 0.014, and 0.021 mag for the B, V, g', r', and i' bands, respectively. The equally high external accuracy of APASS photometry has been verified on secondary Landolt and Sloan photometric standard stars not involved in the APASS calibration process and on a large body of literature data on field and cluster stars, confirming the absence of offsets and trends. Compared with the Carlsberg Meridian Catalog (CMC-15), APASS astrometry of RAVE stars is accurate to a median value of 0.098 arcsec. Brightness distribution functions for the RAVE stars have been derived in all bands. APASS photometry of RAVE stars, augmented by 2MASS JHK infrared data, has been χ{sup 2} fitted to a densely populated synthetic photometric library designed to widely explore temperature, surface gravity, metallicity, and reddening. Resulting T {sub eff} and E {sub B–V}, computed over a range of options, are provided and discussed, and will be kept updated in response to future APASS and RAVE data releases. In the process, we find that the reddening caused by a homogeneous slab of dust, extending for 140 pc on either side of the Galactic plane and responsible for E{sub B−V}{sup poles} = 0.036 ± 0.002 at the Galactic poles, is a suitable approximation of the actual reddening encountered at Galactic latitudes |b| ≥ 25°.

  9. Determination of palladium by flame photometry; Determinacion de paladio por fotometria de llama

    Energy Technology Data Exchange (ETDEWEB)

    Parallada Bellod, R.


    A study on the determination of palladium by lame photometry, fixing the most convent experimental conditions and using solvents to increase the emission of this elements is carried out. Among the organic solvents, acetone has been found the most efficient. The interferences produced by anions and cations have also been studied and an analytical method is related, in which lines of calibration of 0 to 100 ppm palladium re used. (Author) 7 refs.

  10. Photometry-based estimation of the total number of stars in the Universe. (United States)

    Manojlović, Lazo M


    A novel photometry-based estimation of the total number of stars in the Universe is presented. The estimation method is based on the energy conservation law and actual measurements of the extragalactic background light levels. By assuming that every radiated photon is kept within the Universe volume, i.e., by approximating the Universe as an integrating cavity without losses, the total number of stars in the Universe of about 6×1022 has been obtained.

  11. Optimal Stellar Photometry for Multi-conjugate Adaptive Optics Systems Using Science-based Metrics (United States)

    Turri, P.; McConnachie, A. W.; Stetson, P. B.; Fiorentino, G.; Andersen, D. R.; Bono, G.; Massari, D.; Véran, J.-P.


    We present a detailed discussion of how to obtain precise stellar photometry in crowded fields using images from multi-conjugate adaptive optics (MCAO) systems, with the intent of informing the scientific development of this key technology for the Extremely Large Telescopes. We use deep J and K s exposures of NGC 1851 taken with the Gemini Multi-Conjugate Adaptive Optics System (GeMS) on Gemini South to quantify the performance of the instrument and to develop an optimal strategy for stellar photometry using point-spread function (PSF)-fitting techniques. We judge the success of the various methods we employ by using science-based metrics, particularly the width of the main sequence turnoff region. We also compare the GeMS photometry with the exquisite HST data in the visible of the same target. We show that the PSF produced by GeMS possesses significant spatial and temporal variability that must be accounted for during the analysis. We show that the majority of the variation of the PSF occurs within the “control radius” of the MCAO system and that the best photometry is obtained when the PSF radius is chosen to closely match this spatial scale. We identify photometric calibration as a critical issue for next-generation MCAO systems such as those on the Thirty Meter Telescope and European Extremely Large Telescope. Our final CMDs reach K s ˜ 22—below the main sequence knee—making it one of the deepest for a globular cluster available from the ground. Theoretical isochrones are in remarkable agreement with the stellar locus in our data from below the main sequence knee to the upper red giant branch.

  12. Comparing simulations and test data of a radiation damaged CCD for the Euclid mission (United States)

    Skottfelt, Jesper; Hall, David; Gow, Jason; Murray, Neil; Holland, Andrew; Prod'homme, Thibaut


    The radiation damage effects from the harsh radiative environment outside the Earth's atmosphere can be a cause for concern for most space missions. With the science goals becoming ever more demanding, the requirements on the precision of the instruments on board these missions also increases, and it is therefore important to investigate how the radiation induced damage affects the Charge-Coupled Devices (CCDs) that most of these instruments rely on. The primary goal of the Euclid mission is to study the nature of dark matter and dark energy using weak lensing and baryonic acoustic oscillation techniques. The weak lensing technique depends on very precise shape measurements of distant galaxies obtained by a large CCD array. It is anticipated that over the 6 year nominal lifetime of mission, the CCDs will be degraded to an extent that these measurements will not be possible unless the radiation damage effects are corrected. We have therefore created a Monte Carlo model that simulates the physical processes taking place when transferring signal through a radiation damaged CCD. The software is based on Shockley-Read-Hall theory, and is made to mimic the physical properties in the CCD as close as possible. The code runs on a single electrode level and takes charge cloud size and density, three dimensional trap position, and multi-level clocking into account. A key element of the model is that it takes device specific simulations of electron density as a direct input, thereby avoiding to make any analytical assumptions about the size and density of the charge cloud. This paper illustrates how test data and simulated data can be compared in order to further our understanding of the positions and properties of the individual radiation-induced traps.

  13. Development of large-area CCD-based x-ray detector for macromolecular crystallography (United States)

    Pokric, M.; Allinson, Nigel M.; Jorden, Anthony R.; Cox, Matthew P.; Marshall, Andrew R.; Long, P. G.; Moon, Kevin; Jerram, Paul; Pool, Peter J.; Nave, Colin; Derbyshire, Gareth E.; Helliwell, John R.


    The design and development of an area CCD-based X-ray detector system, using the first CCD imagers specially designed for macromolecular crystallography, is presented. The system is intended to produce the highest quality data for physically small crystals at synchrotron sources through the use of large CCDs--that is approaching wafer scale. This work is part of a large research and development program for advanced X-ray sensor technology, funded by industry and the Particle Physics and Astronomy Research Council in the UK. The detector has been optimized by increasing its efficiency at low X-ray energies for conventional laboratory sources, and offers fast readout and high dynamic range needed for efficient measurements at synchrotron sources. The detector consists of CCDs optically coupled to a X-ray sensitive phosphor via skewed fiber-optic studs. The individual three- sides buttable CCD consists of 2048 X 1536 27 micrometers square pixels (55.3 X 41.5 mm). The pixel size has been optimized to match diffraction spot profiling needs and the high dynamic range required for such applications. The multiple amplifier outputs possess switched responsivity to maximize the trade-off between signal handling capabilities and linearity. The readout noise is 5 electrons rms at a 1 MHz pixel rate at the high responsivity setting. A prototype detector system comprising two close-butted cooled CCDs is being developed. This system employs a high-efficiency scintillator with very low point spread function, skewed optical-fiber studs (instead of the more usual demagnifying tapers) to maximize the system's detective quantum efficiency and minimize optical distortions. Full system specifications and a novel crystallographic data processing are presented.

  14. Multi-Site Simultaneous Time-Resolved Photometry with a Low Cost Electro-Optics System. (United States)

    Gasdia, Forrest; Barjatya, Aroh; Bilardi, Sergei


    Sunlight reflected off of resident space objects can be used as an optical signal for astrometric orbit determination and for deducing geometric information about the object. With the increasing population of small satellites and debris in low Earth orbit, photometry is a powerful tool in operational support of space missions, whether for anomaly resolution or object identification. To accurately determine size, shape, spin rate, status of deployables, or attitude information of an unresolved resident space object, multi-hertz sample rate photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. OSCOM, which stands for Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a low cost and portable telescope system capable of time-resolved small satellite photometry, and is field deployable on short notice for simultaneous observation from multiple sites. We present the electro-optical design principles behind OSCOM and light curves of the 1.5 U DICE-2 CubeSat and simultaneous observations of the main body of the ASTRO-H satellite after its fragmentation event.

  15. VizieR Online Data Catalog: Three O-type binaries photometry in LMC (Morrell+, 2014) (United States)

    Morrell, N. I.; Massey, P.; Neugent, K. F.; Penny, L. R.; Gies, D. R.


    We will concentrate on the presentation and discussion of our photometric and spectroscopic observations of 3 binary systems containing the earliest type components among the observed sample of 17 binaries in the LMC, namely, LMC 169782, LMC 171520, and [P93] 921. All three systems belong to the 30 Dor region, which harbors some of the most massive stars known to date (Crowther et al. 2010MNRAS.408..731C; Schnurr et al. 2009MNRAS.395..823S).Time-resolved photometry was carried out for all three systems in order to provide the light curves needed to establish periods and calculate orbital inclinations. As described in Paper I (Massey et al. 2012ApJ...748...96M), this was carried out using simple aperture photometry as opposed to point-spread-function fitting; tests showed that we obtained equally accurate results with aperture photometry, which was expected given that our targets are not overly crowded. In order to compute the observed absolute magnitudes for our targets, we have assumed a distance modulus of 18.50 (50 kpc) for the LMC following van den Bergh (2000, The Galaxies of the Local Group (Cambridge: Cambridge Univ. Press)), and we have used the intrinsic colors given by FitzGerald (1970A&A.....4..234F) and a normal reddening law with Rv = 3.1. (3 data files).

  16. Multi-Site Simultaneous Time-Resolved Photometry with a Low Cost Electro-Optics System

    Directory of Open Access Journals (Sweden)

    Forrest Gasdia


    Full Text Available Sunlight reflected off of resident space objects can be used as an optical signal for astrometric orbit determination and for deducing geometric information about the object. With the increasing population of small satellites and debris in low Earth orbit, photometry is a powerful tool in operational support of space missions, whether for anomaly resolution or object identification. To accurately determine size, shape, spin rate, status of deployables, or attitude information of an unresolved resident space object, multi-hertz sample rate photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. OSCOM, which stands for Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a low cost and portable telescope system capable of time-resolved small satellite photometry, and is field deployable on short notice for simultaneous observation from multiple sites. We present the electro-optical design principles behind OSCOM and light curves of the 1.5 U DICE-2 CubeSat and simultaneous observations of the main body of the ASTRO-H satellite after its fragmentation event.

  17. The research of digital circuit system for high accuracy CCD of portable Raman spectrometer (United States)

    Yin, Yu; Cui, Yongsheng; Zhang, Xiuda; Yan, Huimin


    The Raman spectrum technology is widely used for it can identify various types of molecular structure and material. The portable Raman spectrometer has become a hot direction of the spectrometer development nowadays for its convenience in handheld operation and real-time detection which is superior to traditional Raman spectrometer with heavy weight and bulky size. But there is still a gap for its measurement sensitivity between portable and traditional devices. However, portable Raman Spectrometer with Shell-Isolated Nanoparticle-Enhanced Raman Spectroscopy (SHINERS) technology can enhance the Raman signal significantly by several orders of magnitude, giving consideration in both measurement sensitivity and mobility. This paper proposed a design and implementation of driver and digital circuit for high accuracy CCD sensor, which is core part of portable spectrometer. The main target of the whole design is to reduce the dark current generation rate and increase signal sensitivity during the long integration time, and in the weak signal environment. In this case, we use back-thinned CCD image sensor from Hamamatsu Corporation with high sensitivity, low noise and large dynamic range. In order to maximize this CCD sensor's performance and minimize the whole size of the device simultaneously to achieve the project indicators, we delicately designed a peripheral circuit for the CCD sensor. The design is mainly composed with multi-voltage circuit, sequential generation circuit, driving circuit and A/D transition parts. As the most important power supply circuit, the multi-voltage circuits with 12 independent voltages are designed with reference power supply IC and set to specified voltage value by the amplifier making up the low-pass filter, which allows the user to obtain a highly stable and accurate voltage with low noise. What's more, to make our design easy to debug, CPLD is selected to generate sequential signal. The A/D converter chip consists of a correlated

  18. Determining the Spectral Resolution of a Charge-Coupled Device (CCD) Raman Instrument

    DEFF Research Database (Denmark)

    Liu, Chuan; Berg, Rolf W.


    A new method based on dispersion equations is described to express the spectral resolution of an applied charge-coupled device (CCD) Czerny-Turner Raman instrument entirely by means of one equation and principal factors determined by the actual setup. The factors involved are usual quantities...... widths is also provided. A final finding was that the known significant changes in spectral resolution along the Raman shift axis make static recording and synchronous (extended) scanning modes differ significantly with respect to their resolution properties; this feature has been often overlooked...

  19. CCD measurements of double and multiple stars at NAO Rozhen: II

    Directory of Open Access Journals (Sweden)

    Cvetković Z.


    Full Text Available Using the 2-m telescope of the Bulgarian National Astronomical Observatory at Rozhen observations of twenty multiple stars were carried out during one whole night - October 30/31, and, also, during the first half of the next one - October 31. 2005. This is the second series of CCD measurements of double and multiple stars done at Rozhen. In the paper we present the results for the position angle and separation for eleven multiple stars (35 pairs which could have been measured.

  20. A CCD Photometric Study and Search for Pulsations in RZ Dra and EG Cep (United States)

    Pazhouhesh, R.; Liakos, A.; Niarchos, P.


    This paper presents CCD observations of the Algol-type eclipsing binaries RZ Dra and EG Cep. The light curves have been analyzed with the PHOEBE software and Wilson-Devinney code (2003 version). A detailed photometric analysis, based on these observations, is presented for both binarity and pulsation. The results indicate semidetached systems where the secondary component fills its Roche lobe. After the subtraction of the theoretical light curve, a frequency analysis was performed in order to check for pulsations of the primary component of each system. Moreover, a period analysis was performed for each case in order to search for additional components around the eclipsing pairs.

  1. The overlapping plates method applied to CCD observations of 243 Ida (United States)

    Owen, W. M., Jr.; Yeomans, D. K.


    The overlapping plates method has been applied to crossing-point Charge Coupled Device (CCD) observations of minor planet 243 Ida to produce absolute position measurements precise to better than 0.1 sec and differential position measurements precise to better than 0.06 sec. Although these observations numbered only 17 out of the 520 that produced the final ground-based Ida ephemeris for the Galileo spacecraft flyby, their inclusion decreased Ida's downtrack error from 78 to 60 km and its out-of-plane error from 58 to 44 km.

  2. Measurement of charge of heavy ions in emulsion using a CCD camera

    CERN Document Server

    Kudzia, D; Dabrowska, A; Deines-Jones, P; Holynski, R; Olszewski, A; Nilsen, B S; Sen-Gupta, K; Szarska, M; Trzupek, A; Waddington, C J; Wefel, J P; Wilczynska, B; Wilczynski, H; Wolter, W; Wosiek, B; Wozniak, K


    A system has been developed for semi-automated determination of the charges of heavy ions recorded in nuclear emulsions. The profiles of various heavy ion tracks in emulsion, both accelerator beam ions and fragments of heavy projectiles, were obtained with a CCD camera mounted on a microscope. The dependence of track profiles on illumination, emulsion grain size and density, background in emulsion, and track geometry was analyzed. Charges of the fragments of heavy projectiles were estimated independently by the delta ray counting method. A calibration of both width and height of track profiles against ion charges was made with ions of known charges ranging from helium to gold nuclei. (author)

  3. Measurement of charge of heavy ions in emulsion using a CCD camera

    Energy Technology Data Exchange (ETDEWEB)

    Kudzia, D.; Cherry, M.L.; Dabrowska, A.; Deines-Jones, P.; Holynski, R.; Olszewski, A.; Nilsen, B.S.; Sengupta, K.; Szarska, M.; Trzupek, A.; Waddington, C.J.; Wefel, J.P.; Wilczynska, B.; Wilczynski, H. E-mail:; Wolter, W.; Wosiek, B.; Wozniak, K


    A system has been developed for semi-automated determination of the charges of heavy ions recorded in nuclear emulsions. The profiles of various heavy ion tracks in emulsion, both accelerator beam ions and fragments of heavy projectiles, were obtained with a CCD camera mounted on a microscope. The dependence of track profiles on illumination, emulsion grain size and density, background in emulsion, and track geometry was analyzed. Charges of the fragments of heavy projectiles were estimated independently by the delta ray counting method. A calibration of both width and height of track profiles against ion charges was made with ions of known charges ranging from helium to gold nuclei. (author)

  4. Exploration of multidimensional interactive classroom teaching for CCD principle and application course (United States)

    Fu, Xinghu; Tan, Ailing; Zhang, Baojun; Fu, Guangwei; Bi, Weihong


    The CCD principle and application course is professional and comprehensive. It involves many subject contents. The course content includes eight aspects. In order to complete the teaching tasks within a limited time, improve the classroom teaching quality and prompt students master the course content faster and better, so the multidimensional interactive classroom teaching is proposed. In the teaching practice, the interactive relationship between the frontier science, scientific research project, living example and classroom content is researched detailedly. Finally, it has been proved practically that the proposed multidimensional interactive classroom teaching can achieved good teaching effect.

  5. Hvad skal vi med skønlitteraturen?

    DEFF Research Database (Denmark)

    Bundsgaard, Jeppe; Oksbjerg, Marianne


    didaktiske læremidler, der produceres i disse år, lægges der ikke op til en udnyttelse af skønlitteraturens potentiale for at danne eleverne til demokratiske borgere. I denne artikel beskriver vi, hvad der er galt med læremidlerne. Desuden skitserer vi kriterier for formulering af elevopgaver, der lægger op...

  6. Detoxification of chromium (VI) in coastal water using lignocellulosic ...

    African Journals Online (AJOL)

    In the present study, attempts have been made to harness lignocellulosic agricultural waste material (bagasse) for the removal of chromium (VI) from highly saline coastal water used for aquacultural practices using brackish water. Five different products prepared from bagasse were evaluated for the detoxification of Cr(VI) ...

  7. Biosorption of chromium(VI) using immobilized Bacillius subtilis and ...

    African Journals Online (AJOL)

    Therefore, the batch removal of Cr (VI) from environment water bodies becomes necessary. Its removal from aqueous solution using immobilized Bacillus subtilis (IBBS), Pseudomonas aeruginosa (IPBS), mixed biomass (IMBS) and Alginate alone (IABS) was carried out. The conditions of influence of initial Cr (VI) ...

  8. Predicting chromium (VI) adsorption rate in the treatment of liquid ...

    African Journals Online (AJOL)

    The adsorption rate of chromium (VI) on commercial activated carbon during the treatment of the flocculation effluent of liquid-phase oil-based drill-cuttings has been investigated in terms of contact time and initial chromium (VI) ion concentration. Homogenizing 1 g of the activated carbon with 100 ml of the flocculation ...

  9. Moderate selenium dosing inhibited chromium (VI) toxicity in chicken liver. (United States)

    Wang, Yang; Liu, Yongxia; Wan, Huiyu; Zhu, Yiran; Chen, Peng; Hao, Pan; Cheng, Ziqiang; Liu, Jianzhu


    This study aimed to clarify the effect of selenium (Se) on chromium (VI) [Cr(VI)]-induced damage in chicken liver. A total of 105 chickens were randomly divided into seven groups of 15. Group I received deionized water; group II received Cr(VI) (7.83 mg/kg/d) alone; and other groups orally received both Cr(VI) (7.83 mg/kg/d) and Se of different doses (0.14, 0.29, 0.57, 1.14, and 2.28 mg/kg/d). The levels of superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), Ca2+ -ATPase, and mitochondrial membrane potential (MMP) were measured. Results showed that Cr(VI) increased MDA content and decreased GSH content, T-SOD activity, Ca2+ -ATPase activity, and MMP level. Meanwhile, Se co-treatment (0.14, 0.29, and 0.57 mg/kg/d) increased the viability of the above indicators compared with Cr(VI)-treatment alone. In addition, histopathologic examination revealed that Cr(VI) can cause liver damage, whereas Se supplementation of moderate dose inhibited this damage. This study confirmed that Se exerted protective effect against Cr(VI)-induced liver damage. © 2017 Wiley Periodicals, Inc.

  10. Kandinsky's "Composition VI": Heideggerian Poetry in Noah's Ark (United States)

    Hall, Joshua M.


    The author will begin his investigation of Wassily Kandinsky's painting "Composition VI" with Kandinsky's own commentary on the painting. He will then turn to the analysis of Kandinsky and the "Compositions" in John Sallis's book "Shades." Using this analysis as his point of departure, the author will consider how "Composition VI" resonates with…

  11. Museo del oro: viñetas

    Directory of Open Access Journals (Sweden)

    Les Field


    Full Text Available En enero de 2011 convocamos a un grupo internacional de académicos/activistas para discutir en Colombia las complejidades de la relación entre arqueología, excavaciones “ilícitas”, museos y comunidades indígenas desde una mirada comparativa. El taller de tres días tuvo lugar en Bogotá y Villa de Leyva. Uno de los eventos programados durante los dos días de la parte bogotana del taller fue una visita al Museo del Oro. En el restaurante del museo conversamos sobre lo que acabábamos de ver, sentir y pensar, y surgieron estas impresiones en las que el estupor convive con un fuerte deseo por decir algo. En Villa de Leyva nació la idea de que cada uno de nosotros transcribiera sus emociones en formato de viñeta.

  12. A Video Tour through ViSta 6.4

    Directory of Open Access Journals (Sweden)

    J. Gabriel Molina


    Full Text Available This paper offers a visual tour throughout ViSta 6.4, a freeware statistical program based on Lisp-Stat and focused on techniques for statistical visualization (Young 2004. This travel around ViSta is based on screen recordings that illustrate the main features of the program in action. The following aspects of ViSta 6.4 are displayed: the program's interface (ViSta's desktop, menubar and pop-up menus, help system; its data management capabilities (data input and editing, data transformations; features associated to data analysis (data description, statistical modeling; and the options for Lisp-Stat development in ViSta. The video recordings associated to this tour (.wmv files can be visualized at using the Internet Explorer navigator, or by clicking on the figures in the paper.

  13. Biosorption of uranium (VI) by immobilized Aspergillus fumigatus beads

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jingsong, E-mail: [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China) and Hunan Key Laboratory of Pollution Control and Resource Reuse, University of South China, Henyang, Hunan 421001 (China); Hu Xinjiang [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China); College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Liu Yunguo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Xie Shuibo [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China); Hunan Key Laboratory of Pollution Control and Resource Reuse, University of South China, Henyang, Hunan 421001 (China); Bao Zhenglei [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China)


    Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L{sup -1}. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model.

  14. Development of photoelectric balanced car based on the linear CCD sensor

    Directory of Open Access Journals (Sweden)

    Wang Feng


    Full Text Available The smart car is designed based on Freescale’s MC9S12XS128 and a linear CCD camera. The linear CCD collects the road information and sends it to MCU through the operational amplifier. The PID control algorithm, the proportional–integral–derivative control algorithm, is adopted synthetically to control the smart car. First, the smart car’s inclination and angular velocity are detect through the accelerometers and gyro sensors, then the PD control algorithm, the proportional–derivative control algorithm, is employed to make the smart car have the ability of two-wheeled self-balancing. Second, the speed of wheel obtained by the encoder is fed back to the MCU by way of pulse signal, then the PI control algorithm, the proportional–integral control algorithm, is employed to make the speed of smart car reach the set point in the shortest possible time and stabilize at the set point. Finally, the PD control algorithm is used to regulate the smart car’s turning angle to make the smart car respond quickly while the smart car is passing the curve path. The smart car can realize the self-balancing control of two wheels and track automatically the black and while lines to march.

  15. A comparison of EMCCD, CCD and emerging technologies optimized for low light spectroscopy applications. (United States)

    O'Grady, Antoinette


    Electron multiplying CCDs have revolutionized the world of low light imaging by bringing improved detection limits along with high readout rates; however, it remains to be seen whether they offer any benefits to the world of spectroscopy. Here we review the performance of current CCD and EMCCD detectors and compare their performance for low light level spectroscopy applications. In particular, we look at the detection limits of both technologies for real applications and examine all the parameters that affect these limits in a practical situation. We compare sensitivities, dark signal, noise factors and readout noise with the latter two as the ultimate limitations for detection. We also look at emerging new technology for low light spectroscopy applications which optimizes the parameters discussed without the disadvantages of the current technologies. Theoretical signal to noise data comparing conventional CCD and EMCCD technologies is presented and discussed. Experimental signal to noise comparisons are made for Raman spectra obtained using both conventional and electron multiplying CCDs in conjunction with a confocal Raman microscope. It is concluded that traditional CCDs have a superior detection limit and equal sensitivity to that of EMCCDs and are far superior for high quality quantitative data measurements.

  16. Improving quantum efficiency and spectral resolution of a CCD through direct manipulation of the depletion region (United States)

    Brown, Craig; Ambrosi, Richard M.; Abbey, Tony; Godet, Olivier; O'Brien, R.; Turner, M. J. L.; Holland, Andrew; Pool, Peter J.; Burt, David; Vernon, David


    Future generations of X-ray astronomy instruments will require position sensitive detectors in the form of charge-coupled devices (CCDs) for X-ray spectroscopy and imaging with the ability to probe the X-ray universe with greater efficiency. This will require the development of CCDs with structures that will improve their quantum efficiency over the current state of the art. The quantum efficiency improvements would have to span a broad energy range (0.2 keV to >15 keV). These devices will also have to be designed to withstand the harsh radiation environments associated with orbits that extend beyond the Earth's magnetosphere. This study outlines the most recent work carried out at the University of Leicester focused on improving the quantum efficiency of an X-ray sensitive CCD through direct manipulation of the device depletion region. It is also shown that increased spectral resolution is achieved using this method due to a decrease in the number of multi-pixel events. A Monte Carlo and analytical models of the CCD have been developed and used to determine the depletion depths achieved through variation of the device substrate voltage, Vss. The models are also used to investigate multi-pixel event distributions and quantum efficiency as a function of depletion depth.

  17. First observations from a CCD all-sky spectrograph at Barentsburg (Spitsbergen

    Directory of Open Access Journals (Sweden)

    S. A. Chernouss


    Full Text Available A digital CCD all-sky spectrograph was made by the Polar Geophysical Institute (PGI to support IPY activity in auroral research. The device was tested at the Barentsburg observatory of PGI during the winter season of 2005–2006. The spectrograph is based on a cooled CCD and a transmission grating. The main features of this spectrograph are: a wide field of view (~180°, a wide spectral range (380–740 nm, a spectral resolution of 0.6 nm, a background level of about 100 R at 1-min exposure time. Several thousand spectra of nightglow and aurora were recorded during the observation season. It was possible to register both the strong auroral emissions, as well as weak ones. Spectra of aurora, including nitrogen and oxygen molecular and atomic emissions, as well as OH emissions of the nightglow are shown. A comparison has been conducted of auroral spectra obtained by the film all-sky spectral camera C-180-S at Spitsbergen during IGY, with spectra obtained at Barentsburg during the last winter season. The relationship between the red (630.0 nm and green (557.7 nm auroral emissions shows that the green emission is dominant near the minimum of the solar cycle activity (2005–2006. The opposite situation is observed during 1958–1959, with a maximum solar cycle activity.

  18. The X-ray mirror telescope and the pn-CCD detector of CAST

    CERN Document Server

    Kuster, M; Englhauser, J; Franz, J; Friedrich, P; Hartmann, R; Kang, D; Kotthaus, R; Lutz, Gerhard; Moralez, J; Serber, W; Strüder, L


    The Cern Axion Solar Telescope - CAST - uses a prototype 9 Tesla LHC superconducting dipole magnet to search for a hypothetical pseudoscalar particle, the axion, which was proposed by theory in the 1980s to solve the strong CP problem and which could be a dark matter candidate. In CAST a strong magnetic field is used to convert the solar axions to detectable photons via inverse Primakoff effect. The resulting X-rays are thermally distributed in the energy range of 1-7 keV and can be observed with conventional X-ray detectors. The most sensitive detector system of CAST is a pn-CCD detector originally developed for XMM-Newton combined with a Wolter I type X-ray mirror system. The combination of a focusing X-ray optics and a state of the art pn-CCD detector which combines high quantum efficiency, good spacial and energy resolution, and low background improves the sensitivity of the CAST experiment such that for the first time the axion photon coupling constant can be probed beyond the best astrophysical constrai...

  19. Proton radiation damage assessment of a CCD for use in a Ultraviolet and Visible Spectrometer (United States)

    Gow, J. P. D.; Mason, J.; Leese, M.; Hathi, B.; Patel, M.


    This paper describes the radiation environment and radiation damage analysis performed for the Nadir and Occultation for MArs Discovery (NOMAD) Ultraviolet and Visible Spectrometer (UVIS) channel launched onboard the ExoMars Trace Gas Orbiter (TGO) in 2016. The aim of the instrument is to map the temporal and spatial variation of trace gases such as ozone and dust/cloud aerosols in the atmosphere of Mars. The instrument consists of a set of two miniature telescope viewing optics which allow for selective input onto the optical bench, where an e2v technologies CCD30-11 will be used as the detector. A Geometry Description Markup Language model of the spacecraft and instrument box was created and through the use of ESA's SPace ENVironment Information System (SPENVIS) an estimate of the 10 MeV equivalent proton fluence was made at a number of radiation sensitive regions within NOMAD, including that of the CCD30-11 which is the focus of this paper. The end of life 10 MeV equivalent proton fluence at the charge coupled device was estimated to be 4.7 × 109 three devices were irradiated at different levels up a 10 MeV equivalent fluence of 9.4 × 109 The dark current, charge transfer inefficiency, charge storage, and cosmetic quality of the devices was investigated pre- and post-irradiation, determining that the devices will continue to provide excellent science throughout the mission.

  20. Multi-spectral CCD camera system for ocean water color and seacoast observation (United States)

    Zhu, Min; Chen, Shiping; Wu, Yanlin; Huang, Qiaolin; Jin, Weiqi


    One of the earth observing instruments on HY-1 Satellite which will be launched in 2001, the multi-spectral CCD camera system, is developed by Beijing Institute of Space Mechanics & Electricity (BISME), Chinese Academy of Space Technology (CAST). In 798 km orbit, the system can provide images with 250 m ground resolution and a swath of 500 km. It is mainly used for coast zone dynamic mapping and oceanic watercolor monitoring, which include the pollution of offshore and coast zone, plant cover, watercolor, ice, terrain underwater, suspended sediment, mudflat, soil and vapor gross. The multi- spectral camera system is composed of four monocolor CCD cameras, which are line array-based, 'push-broom' scanning cameras, and responding for four spectral bands. The camera system adapts view field registration; that is, each camera scans the same region at the same moment. Each of them contains optics, focal plane assembly, electrical circuit, installation structure, calibration system, thermal control and so on. The primary features on the camera system are: (1) Offset of the central wavelength is better than 5 nm; (2) Degree of polarization is less than 0.5%; (3) Signal-to-noise ratio is about 1000; (4) Dynamic range is better than 2000:1; (5) Registration precision is better than 0.3 pixel; (6) Quantization value is 12 bit.


    Directory of Open Access Journals (Sweden)

    Y. Liu


    Full Text Available Rational Function Model (RFM is a generic geometric model that has been widely used in geometric processing of high-resolution earth-observation satellite images, due to its generality and excellent capability of fitting complex rigorous sensor models. In this paper, the feasibility and precision of RFM for geometric modeling of China's Chang'E-1 (CE-1 lunar orbiter images is presented. The RFM parameters of forward-, nadir- and backward-looking CE-1 images are generated though least squares solution using virtual control points derived from the rigorous sensor model. The precision of the RFM is evaluated by comparing with the rigorous sensor model in both image space and object space. Experimental results using nine images from three orbits show that RFM can precisely fit the rigorous sensor model of CE-1 CCD images with a RMS residual error of 1/100 pixel level in image space and less than 5 meters in object space. This indicates that it is feasible to use RFM to describe the imaging geometry of CE-1 CCD images and spacecraft position and orientation. RFM will enable planetary data centers to have an option to supply RFM parameters of orbital images while keeping the original orbit trajectory data confidential.

  2. [Atmospheric correction of HJ-1 CCD data for water imagery based on dark object model]. (United States)

    Zhou, Li-Guo; Ma, Wei-Chun; Gu, Wan-Hua; Huai, Hong-Yan


    The CCD multi-band data of HJ-1A has great potential in inland water quality monitoring, but the precision of atmospheric correction is a premise and necessary procedure for its application. In this paper, a method based on dark pixel for water-leaving radiance retrieving is proposed. Beside the Rayleigh scattering, the aerosol scattering is important to atmospheric correction, the water quality of inland lakes always are case II water and the value of water leaving radiance is not zero. So the synchronous MODIS shortwave infrared data was used to obtain the aerosol parameters, and in virtue of the characteristic that aerosol scattering is relative stabilized in 560 nm, the water-leaving radiance for each visible and near infrared band were retrieved and normalized, accordingly the remotely sensed reflectance of water was computed. The results show that the atmospheric correction method based on the imagery itself is more effective for the retrieval of water parameters for HJ-1A CCD data.

  3. [Retrieval and validation of the surface reflectance using HJ-1-CCD data]. (United States)

    Li, Shen-Shen; Chen, Liang-Fu; Tao, Jin-Hua; Han, Dong; Wang, Zhong-Ting; He, Bao-Hua


    The potentiality of the retrieval of surface reflectance using CCD camera aboard HJ-1A/B satellite was studied. It is very difficult to use dark targets in atmospheric correction due to the lack of near infrared band. The alternative normalized difference vegetation index (NDVI) and the red/blue reflectance ratio are detected from the spectral experiment in Beijing and the Pearl River Delta. Ground-based spectral data including grass, dense vegetation, water body, soil, residential roof and bright building etc. were used to validate the surface reflectance in Beijing, and the relative error in red, blue band is under 38.7% and 37.2% respectively. Uncertainties of the surface reflectance retrievals were analyzed. The comparison of MODIS surface reflectance product showed that there is a good agreement in the dense targets, and the correlation coefficient (R2) in red, blue band is as high as 0.809 4 and 0.723 9 respectively. HJ-1-CCD data can effectively reduce pixel-mixed impact on the cement roof and bright buildings, and the inversion accuracy is higher than MODIS products.

  4. Design of Frame-transferred Surface Array CCD Imaging System for Dark Objects (United States)

    Zhang, Yu-heng; Yan, Yi-hua


    In order to realize the requirement of low-noise observations of dark objects in deep-space explorations, the design method for a simple and stable space camera imaging system is proposed in this paper. Based on the back-illuminated frame-transferred surface array CCD (CCD47-20AIMO) produced by the British E2V company, the circuitry design is given for the every part of the system. In which the applications of the correlated double-sampling analog-digital converter (AD) and the synchronous dynamic random access memory (SDRAM) can effectively suppress the correlated noise in the image signal. In addition, a drive control method favorable to the adjustment of exposure time is proposed, in the light-sensing stage it provides the exposure time with an independent and adjustable time delay to make the imaging system satisfy the requirement of long exposure time setting. The imaging system adopts the Cyclone III-series EP3C25Q240C8 field programable gate array produced by the Altera company as the kernel control device, and the drives are programmed in modules according to the function of the every device, in favor of transplantation. The simulative and experimental results indicate that the drive circuitry works normally, and that the system design can satisfy the preset requirement.

  5. Applications in radiation therapy of a scintillating screen viewed by a CCD camera

    CERN Document Server

    Schippers, J M; Luijk, P V


    A two-dimensional (2D) dosimetry system has been designed for position-sensitive dose-measurement applications in modern radiation therapy. The system consists of a scintillating screen (Gd sub 2 O sub 2 S : Tb), observed by a low-noise CCD camera with a long integration time. The system allows reliable and accurate simultaneous 2D imaging of therapeutic dose distributions in the scintillator with sub millimeter spatial resolution. This system has been applied successfully at different applications in radiation therapy. Results of dose measurements in a treatment modality using a scanning proton beam are reported. It is shown that a quick and reliable measurement can be done. The screen+CCD system has proven to perform accurate dosimetry in applications where beams with a small (1-5 mm) diameter are used and where absolute dosimetry by means of standard ionization chambers is not possible due to their relatively large size. For the routine measurements of the alignment of therapeutic beams with respect to the...

  6. Investigation of uranium (VI) adsorption by polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Abdi, S. [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Nasiri, M., E-mail: [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Mesbahi, A. [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Khani, M.H. [Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, 14395-836 (Iran, Islamic Republic of)


    Highlights: • The adsorbent (polypyrrole) was synthesized by a chemical method using PEG, DBSNa and CTAB as the surfactant. • The solution pH was one of the most important parameters affecting the adsorption of uranium. • The CTAB provided higher removal percentage compared with the other surfactants. • The maximum adsorption capacity obtained from Langmuir isotherm was 87.72 mg/g. • The pseudo second-order model fitted well with the adsorption kinetic of polypyrrole to uranium. - Abstract: The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride as an oxidant in the aqueous solution. The effect of various surfactants on the synthesized polymers and their performance as the uranium adsorbent were investigated. Adsorbent properties were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The effect of different parameters such as pH, contact time, initial metal ion concentrations, adsorbent dose, and the temperature was investigated in the batch system for uranium adsorption process. It has been illustrated that the adsorption equilibrium time is 7 min. The results showed that the Freundlich model had the best agreement and the maximum adsorption capacity of polypyrrole for uranium (VI) was determined 87.72 mg/g from Langmuir isotherm. In addition, the mentioned adsorption process was fast and the kinetic data were fitted to the Pseudo first and second order models. The adsorption kinetic data followed the pseudo-second-order kinetic model. Moreover, the thermodynamic parameters ΔG{sup 0}, ΔH{sup 0} and ΔS{sup 0} showed that the uranium adsorption process by polypyrrole was endothermic and spontaneous.

  7. Six-fold Coordinated Carbon Dioxide VI

    Energy Technology Data Exchange (ETDEWEB)

    Iota, V; Yoo, C; Klepeis, J; Jenei, Z


    Under standard conditions, carbon dioxide (CO{sub 2}) is a simple molecular gas and an important atmospheric constituent while silicon dioxide (SiO{sub 2}) is a covalent solid, and represents one of the fundamental minerals of the planet. The remarkable dissimilarity between these two group IV oxides is diminished at higher pressures and temperatures as CO{sub 2} transforms to a series of solid phases, from simple molecular to a fully covalent extended-solid V, structurally analogous to SiO{sub 2} tridymite. Here, we present the discovery of a new extended-solid phase of carbon dioxide (CO{sub 2}): a six-fold coordinated stishovite-like phase VI, obtained by isothermal compression of associated CO{sub 2}-II above 50GPa at 530-650K. Together with the previously reported CO{sub 2}-V and a-carbonia, this new extended phase indicates a fundamental similarity between CO{sub 2}--a prototypical molecular solid, and SiO{sub 2}--one of Earth's fundamental building blocks. The phase diagram suggests a limited stability domain for molecular CO{sub 2}-I, and proposes that the conversion to extended-network solids above 40-50 GPa occurs via intermediate phases II, III, and IV. The crystal structure of phase VI suggests strong disorder along the caxis in stishovite-like P4{sub 2}/mnm, with carbon atoms manifesting an average six-fold coordination within the framework of sp{sup 3} hybridization.

  8. Contrast reduction in digital images due to x-ray induced damage to a TV camera's CCD image receptor. (United States)

    Okkalides, D


    The CCD image receptor in a monochrome TV camera was irradiated in the dark with a single-phase 80 kVp narrow beam carrying an additional 0.5 mm Al filter. It was found that the CCD responded to the x-rays with a transient signal which would reach a maximum value at about 70 mR per image frame. The signal's contrast would reach a maximum of about 7%, but was detectable at much lower exposure rates. Continuous irradiation of the CCD image receptor created a 'lesion' at the point of incidence that remained after the x-ray beam was switched off. This signal seemed to be due to permanent damage to the CCD and could be detected after a cumulative exposure of less than 20 R. It was shown that such damage could be created much more effectively if the TV camera was switched off rather than on and the maximum contrast was achieved with about 75 R and 220 R respectively. The maximum contrast achieved was about 8%. Further increase in the cumulative exposure of a particular location on the CCD image receptor was not investigated but it seemed reasonable that much higher contrast values could be reached if irradiation was continued. The latter damage described here was found to persist for at least several weeks and hence it will probably prevent any normal use of the TV camera in the future.

  9. cGMP-activating peptides do not regulate electrogenic electrolyte transport in principal cells of rat CCD. (United States)

    Schlatter, E; Cermak, R; Forssmann, W G; Hirsch, J R; Kleta, R; Kuhn, M; Sun, D; Schafer, J A


    K+ channels in the basolateral membrane of rat cortical collecting duct (CCD) are regulated by a cGMP-dependent protein kinase (J. Hirsch and E. Schlatter. Pfluegers Arch. 429: 338-344, 1995). Conflicting data exist on the effects of cGMP-activating agonists on Na+ transport in these cells. Thus we tested members of the family of peptides that increase intracellular cGMP [cardiodilatin/atrial natriuretic peptide (CDD/ANP), brain natriuretic peptide, C-type natriuretic peptide, urodilatin, guanylin, and uroguanylin], as well as bradykinin +/- CDD/ANP on membrane voltages (Vm) of principal cells of isolated rat CCD using the slow whole cell patch-clamp technique (E. Schlatter, U. Fröbe, and R. Greger. Pfluegers Arch. 421: 381-387, 1992). None of the agonists tested changed Vm significantly. There was also no effect of dibutyryl guanosine 3',5'-cyclic monophosphate (DBcGMP) on AVP-dependent lumen-to-bath Na+ flux, transepithelial voltage, or osmotic water permeability in isolated perfused rat CCD. Finally, CDD/ANP increased intracellular cGMP only in glomeruli but not in CCD. Thus the findings provide no evidence for control of electrogenic electrolyte transport by these natriuretic peptides in principal cells of rat CCD, and the agonist that physiologically regulates the cGMP-dependent K+ channels remains to be identified.


    Directory of Open Access Journals (Sweden)

    Rasti Januarita


    Full Text Available The effect of initial concentration of Cr(VI on adsorption to black water of Gambut, District of Banjar, South Borneo has been investigated, as well as interaction between Cr(VI species and functional black water organic fraction. The initial work was optimization of Cr(VI determination using UV-Visible Spectrophotometry with diphenylcarbacide as complexing agent and preparation of black water using mixture of 2% HCl and 5% HF with HCl-HF ratio of 1 : 1 (v/v. The quantity of Cr(VI species adsorbed on black water was calculated by determining the amount of Cr(VI species in solution before and after interaction. The functional groups in interaction between Cr(VI species and black water organic fraction was studied qualitatively using infrared spectroscopy. The results showed that optimum condition for Cr(VI species analysis using UV-Visible spectrophotometry with diphenylcarbacide as complexing agent was at wave length of 540 nm, pH 1,5, 15 - 60 minutes at which complex remain stable, and minimum mol ratio of diphenylcarbacide : Cr(VI 45 : 1, and has a sensitivity of 1.134 mg/L and detection limit of 0.00495 mg/L. The analysis was not affected by the presence of Cr(III in concentration less than 40 times of Cr(VI concentration. After treatment with HCl-HF the quantity of black water organic fraction showing humic acid properties decreased 0,1998 percent. Organic fraction of black water used adsorpted Cr(VIwith capacity of 4,050 mg/g.   Keywords: Adsorption, Cr(VI, Black Water

  11. Technology-derived storage solutions for stabilizing insulin in extreme weather conditions I: the ViViCap-1 device. (United States)

    Pfützner, Andreas; Pesach, Gidi; Nagar, Ron


    Injectable life-saving drugs should not be exposed to temperatures 30°C/86°F. Frequently, weather conditions exceed these temperature thresholds in many countries. Insulin is to be kept at 4-8°C/~ 39-47°F until use and once opened, is supposed to be stable for up to 31 days at room temperature (exception: 42 days for insulin levemir). Extremely hot or cold external temperature can lead to insulin degradation in a very short time with loss of its glucose-lowering efficacy. Combined chemical and engineering solutions for heat protection are employed in ViViCap-1 for disposable insulin pens. The device works based on vacuum insulation and heat consumption by phase-change material. Laboratory studies with exposure of ViViCap-1 to hot outside conditions were performed to evaluate the device performance. ViViCap-1 keeps insulin at an internal temperature change process and 'recharges' the device for further use. ViViCap-1 performed within its specifications. The small and convenient device maintains the efficacy and safety of using insulin even when carried under hot weather conditions.

  12. A Survey of Local Group Galaxies Currently Forming Stars. I. UBVRI Photometry of Stars in M31 and M33 (United States)

    Massey, Philip; Olsen, K. A. G.; Hodge, Paul W.; Strong, Shay B.; Jacoby, George H.; Schlingman, Wayne; Smith, R. C.


    We present UBVRI photometry obtained from Mosaic images of M31 and M33 using the Kitt Peak National Observatory 4 m telescope. We describe our data reduction and automated photometry techniques in some detail, as we will shortly perform a similar analysis of other Local Group galaxies. The present study covered 2.2 deg2 along the major axis of M31 and 0.8 deg2 on M33, chosen so as to include all of the regions currently active in forming massive stars. We calibrated our data using photometry from the Lowell 1.1 m telescope, and this external method resulted in millimagnitude differences in the photometry of overlapping fields, providing some assurance that our photometry is reliable. The final catalog contains 371,781 and 146,622 stars in M31 and M33, respectively, where every star has a counterpart in (at least) the B, V, and R passbands. Our survey goes deep enough to achieve 1%-2% photometry at 21 mag (corresponding to stars more massive than 20 Msolar) and achieves projects, we demonstrate the success of our photometry in being able to distinguish M31/M33 members from foreground Galactic stars. Finally, we present the results of a single night of spectroscopy on the WIYN 3.5 m telescope, examining the brightest likely members of M31. The spectra identify 34 newly confirmed members, including B-A supergiants, the earliest O star known in M31, and two new luminous blue variable candidates whose spectra are similar to that of P Cygni. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. These observations are associated with program GO-9794.

  13. Optical photometry of GM Cep: evidence for UXor type of variability


    Semkov, E. H.; Peneva, S. P.


    Results from optical photometric observations of the pre-main sequence star GM Cep are reported in the paper. The star is located in the field of the young open cluster Trumpler 37 - a region of active star formation. GM Cep shows a large amplitude rapid variability interpreted as a possible outburst from EXor type in previous studies. Our data from BVRI CCD photometric observations of the star are collected from June 2008 to February 2011 in Rozhen observatory (Bulgaria) and Skinakas observa...

  14. The FUSE Survey of 0 VI in the Galactic Halo (United States)

    Sonneborn, George; Savage, B. D.; Wakker, B. P.; Sembach, K. R.; Jenkins, E. B.; Moos, H. W.; Shull, J. M.


    This paper summarizes the results of the Far-Ultraviolet Spectroscopic Explorer (FUSE) program to study 0 VI in the Milky Way halo. Spectra of 100 extragalactic objects and two distant halo stars are analyzed to obtain measures of O VI absorption along paths through the Milky Way thick disk/halo. Strong O VI absorption over the velocity range from -100 to 100 km/s reveals a widespread but highly irregular distribution of O VI, implying the existence of substantial amounts of hot gas with T approx. 3 x 10(exp 5) K in the Milky Way thick disk/halo. The overall distribution of O VI is not well described by a symmetrical plane-parallel layer of patchy O VI absorption. The simplest departure from such a model that provides a reasonable fit to the observations is a plane-parallel patchy absorbing layer with an average O VI mid-plane density of n(sub 0)(O VI) = 1.7 x 10(exp -2)/cu cm, a scale height of approx. 2.3 kpc, and a approx. 0.25 dex excess of O VI in the northern Galactic polar region. The distribution of O VI over the sky is poorly correlated with other tracers of gas in the halo, including low and intermediate velocity H I, Ha emission from the warm ionized gas at approx. l0(exp 4) K, and hot X-ray emitting gas at approx. l0(exp 6) K . The O VI has an average velocity dispersion, b approx. 60 km/s and standard deviation of 15 km/s. Thermal broadening alone cannot explain the large observed profile widths. A combination of models involving the radiative cooling of hot fountain gas, the cooling of supernova bubbles in the halo, and the turbulent mixing of warm and hot halo gases is required to explain the presence of O VI and other highly ionized atoms found in the halo. The preferential venting of hot gas from local bubbles and superbubbles into the northern Galactic polar region may explain the enhancement of O VI in the North.

  15. A highly selective sorbent for removal of Cr(VI) from aqueous solutions based on Fe{sub 3}O{sub 4}/poly(methyl methacrylate) grafted Tragacanth gum nanocomposite: Optimization by experimental design

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, Susan, E-mail:; Rad, Fatemeh Alavi; Moghaddam, Ali Zeraatkar


    In this work, poly(methyl methacrylate) grafted Tragacanth gum modified Fe{sub 3}O{sub 4} magnetic nanoparticles (P(MMA)-g-TG-MNs) were developed for the selective removal of Cr(VI) species from aqueous solutions in the presence of Cr(III). The sorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), and thermo-gravimetric analysis (TGA). A screening study on operational variables was performed using a two-level full factorial design. Based on the analysis of variance (ANOVA) with 95% confidence limit, the significant variables were found. The central composite design (CCD) has also been employed for statistical modeling and analysis of the effects and interactions of significant variables dealing with the Cr(VI) uptake process by the developed sorbent. The predicted optimal conditions were situated at a pH of 5.5, contact time of 3.4 h, and 3.0 g L{sup −1} dose. The Langmuir, Freundlich, and Temkin isotherm models were used to describe the equilibrium sorption of Cr(VI) by the absorbent, and the Langmuir isotherm showed the best concordance as an equilibrium model. The adsorption process was followed by a pseudo-second-order kinetic model. Thermodynamic investigations showed that the biosorption process was spontaneous and exothermic. - Highlights: • Fe3O4 nanoparticles were modified with Poly(methyl methacrylate) grafted Tragacanth gum • P(MMA)-g-TG -MNPs can preferentially adsorb Cr(VI) in the presence of Cr(III) • The effects of operational parameters on Cr(VI) removal were evaluated by RSM • Adsorption mechanism, kinetics, and isotherm have been explored • The sorbent was successfully used to remove Cr(VI) from different water samples.

  16. VizieR Online Data Catalog: Spectroscopy and photometry for HAT-P-50--HAT-P-53 (Hartman+, 2015) (United States)

    Hartman, J. D.; Bhatti, W.; Bakos, G. A.; Bieryla, A.; Kovacs, G.; Latham, D. W.; Csubry, Z.; de Val-Borro, M.; Penev, K.; Buchhave, L. A.; Torres, G.; Howard, A. W.; Marcy, G. W.; Johnson, J. A.; Isaacson, H.; Sato, B.; Boisse, I.; Falco, E.; Everett, M. E.; Szklenar, T.; Fulton, B. J.; Shporer, A.; Kovacs, T.; Hansen, T.; Beky, B.; Noyes, R. W.; Lazar, J.; Papp, I.; Sari, P.


    The HATNet network consists of six identical fully automated instruments, with four at Fred Lawrence Whipple Observatory (FLWO) in AZ, and two on the roof of the Submillimeter Array Hangar Building at Mauna Kea Observatory (MKO) in HI. The light-gathering elements of each instrument include an 11cm diameter telephoto lens, a Sloan r filter, and a 4K*4K front-side-illuminated CCD camera. Observations made in 2007 and early 2008 were carried out using a Cousins R filter. The instruments have a field of view of 10.6°*10.6° and a pixel scale of 9"/pixel at the center of an image. Additional time-series photometric measurements were obtained for all four of the systems using Keplercam on the FLWO 1.2m telescope. For HAT-P-50 we also obtained follow-up photometry with the CCD imager on the Byrne Observatory at Sedgwick (BOS) 0.8m telescope, located at Sedgwick Reserve in Santa Ynez Valley, CA, and operated by the Las Cumbres Observatory Global Telescope institute (LCOGT). HAT-P-50 was observed with HAT-10/G316 on 2008 Nov-2009 May, with HAT-5/G364 on 2009 May, with HAT-9/G364 on 2008 Dec-2009 May, with BOS on 2012 Feb 15, on 2012 Feb 21 and on 2012 Apr 08, and with Keplercam on 2012 Feb 18, on 2012 Nov 28, on 2012 Dec 23, on 2013 Jan 14, and on 2013 Jan 17. HAT-P-51 was observed with HAT-6/G164 on 2007 Sep-2008 Feb, with HAT-9/G164 on 2007 Sep-2008 Feb, with HAT-10/G165 on 2010 Sep-2011 Jan, with HAT-5/G165 on 2010 Nov-2011 Feb, with HAT-8/G165 on 2010 Nov-2011 Feb, with HAT-6/G209 on 2010 Nov-2011 Feb, with HAT-9/G209 on 2010 Nov-2011 Feb, with HAT-7/G210 on 2010 Nov-2011 Jan, and with Keplercam on 2011 Oct 21, on 2012 Jan 05, on 2012 Oct 05, on 2012 Oct 26, and on 2012 Nov 12. HAT-P-52 was observed with HAT-5/G212 on 2010 Sep-Nov, with HAT-8/G212 on 2010 Aug-Nov, and with Keplercam on 2010 Dec 23, on 2011 Sep 05, on 2011 Sep 27, on 2011 Nov 21, and on 2012 Jan 07. HAT-P-53 was observed with HAT-6/G164 on 2007 Sep-2008 Feb, with HAT-9/G164 on 2007 Sep-2008 Feb, with

  17. Improvement in the light sensitivity of the ultrahigh-speed high-sensitivity CCD with a microlens array (United States)

    Hayashida, T.,; Yonai, J.; Kitamura, K.; Arai, T.; Kurita, T.; Tanioka, K.; Maruyama, H.; Etoh, T. Goji; Kitagawa, S.; Hatade, K.; Yamaguchi, T.; Takeuchi, H.; Iida, K.


    We are advancing the development of ultrahigh-speed, high-sensitivity CCDs for broadcast use that are capable of capturing smooth slow-motion videos in vivid colors even where lighting is limited, such as at professional baseball games played at night. We have already developed a 300,000 pixel, ultrahigh-speed CCD, and a single CCD color camera that has been used for sports broadcasts and science programs using this CCD. However, there are cases where even higher sensitivity is required, such as when using a telephoto lens during a baseball broadcast or a high-magnification microscope during science programs. This paper provides a summary of our experimental development aimed at further increasing the sensitivity of CCDs using the light-collecting effects of a microlens array.

  18. Realization of the Vilnius photometric system for CCD-observations of selected sky areas at the Andrushivka Astronomical Observatory (United States)

    Andruk, V.; Butenko, G.; Gerashchenko, O.; Ivashchenko, Yu.; Kovalchuk, G.; Lokot', V.; Samoylov, V.


    We describe a set of glass UPXYZVS filters of the Vilnius photometric system of the Andrushivka Astronomical Observatory in Zhytomyr Region (Ukraine) [7]. They are installed at the Zeiss-600 Cassegrain reflector together with the 15-bit 1024×1024 CCD-camera S1C-017. The response curves of instrumental photometric systems are presented and a comparison of them with a standard system are analysed. Test observations in the Vilnius system of the star cluster IC 4665 with the Andrushivka filters were carried out in May--June 2003. The MIDAS/ROMAFOT and ASTROIMAGE software is adapted for digital processing of CCD-images of stellar fields. Comprehensive ground-based observations are being planned to design a catalogue of primary UPXYZVS CCD-standards in selected areas of the sky where are with radio sources, globular and open clusters, etc.

  19. Realization of Vilnius UPXYZVS photometric system for AltaU42 CCD camera at the MAO NAS of Ukraine (United States)

    Vid'Machenko, A. P.; Andruk, V. M.; Samoylov, V. S.; Delets, O. S.; Nevodovsky, P. V.; Ivashchenko, Yu. M.; Kovalchuk, G. U.


    The description of two-inch glass filters of the Vilnius UPXYZVS photometric system, which are made at the Main Astronomical Observatory of NAS of Ukraine for AltaU42 CCD camera with format of 2048×2048 pixels, is presented in the paper. Reaction curves of instrumental system are shown. Estimations of minimal star's magnitudes for each filter's band in comparison with the visual V one are obtained. New software for automation of CCD frames processing is developed in program shell of LINUX/MIDAS/ROMAFOT. It is planned to carry out observations with the purpose to create the catalogue of primary UPXYZVS CCD standards in selected field of the sky for some radio-sources, globular and open clusters, etc. Numerical estimations of astrometric and photometric accuracy are obtained.

  20. A method of immediate detection of objects with a near-zero apparent motion in series of CCD-frames (United States)

    Savanevych, V. E.; Khlamov, S. V.; Vavilova, I. B.; Briukhovetskyi, A. B.; Pohorelov, A. V.; Mkrtichian, D. E.; Kudak, V. I.; Pakuliak, L. K.; Dikov, E. N.; Melnik, R. G.; Vlasenko, V. P.; Reichart, D. E.


    The paper deals with a computational method for detection of the solar system minor bodies (SSOs), whose inter-frame shifts in series of CCD-frames during the observation are commensurate with the errors in measuring their positions. These objects have velocities of apparent motion between CCD-frames not exceeding three rms errors (3σ) of measurements of their positions. About 15% of objects have a near-zero apparent motion in CCD-frames, including the objects beyond the Jupiter's orbit as well as the asteroids heading straight to the Earth. The proposed method for detection of the object's near-zero apparent motion in series of CCD-frames is based on the Fisher f-criterion instead of using the traditional decision rules that are based on the maximum likelihood criterion. We analyzed the quality indicators of detection of the object's near-zero apparent motion applying statistical and in situ modeling techniques in terms of the conditional probability of the true detection of objects with a near-zero apparent motion. The efficiency of method being implemented as a plugin for the Collection Light Technology (CoLiTec) software for automated asteroids and comets detection has been demonstrated. Among the objects discovered with this plugin, there was the sungrazing comet C/2012 S1 (ISON). Within 26 min of the observation, the comet's image has been moved by three pixels in a series of four CCD-frames (the velocity of its apparent motion at the moment of discovery was equal to 0.8 pixels per CCD-frame; the image size on the frame was about five pixels). Next verification in observations of asteroids with a near-zero apparent motion conducted with small telescopes has confirmed an efficiency of the method even in bad conditions (strong backlight from the full Moon). So, we recommend applying the proposed method for series of observations with four or more frames.

  1. Optical system design of multi-spectral and large format color CCD aerial photogrammetric camera (United States)

    Qian, Yixian; Sun, Tianxiang; Gao, Xiaodong; Liang, Wei


    Multi-spectrum and high spatial resolution is the vital problem for optical design of aerial photogrammetric camera all the time. It is difficult to obtain an outstanding optical system with high modulation transfer function (MTF) as a result of wide band. At the same time, for acquiring high qualified image, chromatic distortion in optical system must be expected to be controlled below 0.5 pixels; it is a trouble thing because of wide field and multi-spectrum. In this paper, MTF and band of the system are analyzed. A Russar type photogrammetric objective is chosen as the basic optical structure. A novel optical system is presented to solve the problem. The new optical photogrammetric system, which consists of panchromatic optical system and chromatic optical system, is designed. The panchromatic optical system, which can obtain panchromatic image, makes up of a 9k×9k large format CCD and high-accuracy photographic objective len, its focal length is 69.83mm, field angle is 60°×60°, the size of CCD pixels is 8.75um×8.75um, spectral scope is from 0.43um to 0.74um, modulation transfer function is all above 0.4 in whole field when spatial frequency is at 60lp/mm, distortion is less than 0.007%. In a chromatic optical system, three 2k×2k array CCDs combine individually three same photographic objectives, the high resolution chromatic image is acquired by the synthesis of red, green, blue image data information delivered by three CCD sensors. For the chromatic system, their focal length is 24.83mm and they have the same spectral range of 0.39um to 0.74um. A difference is that they are coated in different film on their protect glass. The pixel number is 2048 × 2048; its MTF exceeds 0.4 in full field when spatial frequency is 30lp/mm. The advantages of digital aerial photogrammetric camera comparison with traditional film camera are described. It is considered that the two development trends on digital aerial photogrammetric camera are high-spectral resolution and

  2. Multiple-wavelength double random phase encoding with CCD-plane sparse-phase multiplexing for optical information verification. (United States)

    Chen, Wen


    A novel method is proposed by using multiple-wavelength double random phase encoding (MW-DRPE) with CCD-plane sparse-phase multiplexing for optical information verification. Two different strategies are applied to conduct sparse-phase multiplexing in the CCD plane. The results demonstrate that large capacity can be achieved for optical multiple-image verification. The proposed optical verification strategy is implemented based on optical encoding, and the keys generated by optical encryption can further guarantee the safety of the designed optical multiple-image verification system. The proposed method provides a novel alternative for DRPE-based optical information verification.

  3. Optical manifestations of mass outflows from young stars - At atlas of CCD images of Herbig-Haro objects (United States)

    Strom, K. M.; Strom, S. E.; Wenz, M.; Wolff, S. C.; Morgan, J.


    An attempt is made to provide deep CCD images suitable for tracing the shock-excited and scattered-light components characterizing extended Herbig-Haro complexes. Tabular data include astrometric positions for all stars, shock-excited emission knots, prominent scattered-light patches, as well as an identification for all H-alpha emission objects within the CCD images. It is concluded that: (1) optical outflows are not always accompanied by molecular flows, (2) optical outflows show a higher degree of collimation than their molecular counterparts, and (3) the Herbig-Haro phenomenon is not restricted to low-mass young stellar objects.

  4. VizieR Online Data Catalog: UBV photometry of MWC560 (Tomov+, 1996) (United States)

    Tomov, T.; Kolev, D.; Ivanov, M.; Antov, A.; Jones, A.; Mikolajewski, M.; Lepardo, A.; Passuello, R.; Saccavino, S.; Sostero, G.; Valentinuzzi, T.; Bellas-Velidis, Y.; Dapergolas, A.; Munari, U.


    We present results of an extensive photometric monitoring campaign of the peculiar emission star MWC 560 that covers the range 1990-1995. The time interval corresponds to the length of the proposed orbital period of this highly peculiar binary, which attracted considerable interest in January-April 1990, when absorption components, shifted by -6000km/s from corresponding emission lines, were observed. Here we present photometric data secured during: 113 nights of conventional UBV photoelectric photometry, 45 nights of high speed UBV photoelectric photometry to study the flickering activity, and 682 visual photometric estimates. MWC 560 has experienced a decrease in magnitude since the bright (V=9.2mag) phase in 1990. After the minimum reached in May 1994 (V=10.7mag), the star is currently increasing slowly in brightness. The decrease has been accompanied in all bands by large fluctuations superimposed on the mean trend. The B-V colour has shown a steady increase by 0.0.33mag/yr. U-B has remained stable at -0.07mag since late 1990. In all the observing nights devoted to high speed photometry we observed flickering activity in MWC 560. The data show that the flickering amplitude {DELTA}U increases with the decrease of the U magnitude. Quasi-periodic variations have always been detected. A period of ~70min has been observed in ~13 nights which is close to the ~60min quasi-period reported by Michalitsianos et al. (1993). However, no coherent variability is traceable throughout the whole set of flickering data. (2 data files).

  5. First evidence of multiple populations along the AGB from Strömgren photometry (United States)

    Gruyters, Pieter; Casagrande, Luca; Milone, Antonino P.; Hodgkin, Simon T.; Serenelli, Aldo; Feltzing, Sofia


    Spectroscopic studies have demonstrated that nearly all Galactic globular clusters (GCs) harbour multiple stellar populations with different chemical compositions. Moreover, colour-magnitude diagrams based exclusively on Strömgrem photometry have allowed us to identify and characterise multiple populations along the RGB of a large number of clusters. In this paper we show for the first time that Strömgren photometry is also very efficient at identifying multiple populations along the AGB, and demonstrate that the AGB of M 3, M 92, NGC 362, NGC 1851, and NGC 6752 are not consistent with a single stellar population. We also provide a catalogue of RGB and AGB stars photometrically identified in these clusters for further spectroscopic follow-up studies. We combined photometry and elemental abundances from the literature for RGB and AGB stars in NGC 6752 where the presence of multiple populations along the AGB has been widely debated. We find that, while the MS, SGB, and RGB host three stellar populations with different helium and light element abundances, only two populations of AGB stars are present in the cluster. These results are consistent with standard evolutionary theory. Based on observations made with the Isaac Newton Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.Full Tables B.1 and B.2 are only available at the CDS via anonymous ftp to ( or via

  6. Shape models of asteroids reconstructed from WISE data and sparse photometry (United States)

    Durech, Josef; Hanus, Josef; Ali-Lagoa, Victor


    By combining sparse-in-time photometry from the Lowell Observatory photometry database with WISE observations, we reconstructed convex shape models for about 700 new asteroids and for other ~850 we derived 'partial' models with unconstrained ecliptic longitude of the spin axis direction. In our approach, the WISE data were treated as reflected light, which enabled us to directly join them with sparse photometry into one dataset that was processed by the lightcurve inversion method. This simplified treatment of thermal infrared data turned out to provide correct results, because in most cases the phase offset between optical and thermal lightcurves was small and the correct sidereal rotation period was determined. The spin and shape parameters derived from only optical data and from a combination of optical and WISE data were very similar. The new models together with those already available in the Database of Asteroid Models from Inversion Techniques (DAMIT) represent a sample of ~1650 asteroids. When including also partial models, the total sample is about 2500 asteroids, which significantly increases the number of models with respect to those that have been available so far. We will show the distribution of spin axes for different size groups and also for several collisional families. These observed distributions in general agree with theoretical expectations proving that smaller asteroids are more affected by YORP/Yarkovsky evolution. In asteroid families, we see a clear bimodal distribution of prograde/retrograde rotation that correlates with the position to the right/left from the center of the family measured by the semimajor axis.

  7. Polarimetry and photometry of the peculiar main-belt object 7968 = 133P/Elst-Pizarro (United States)

    Bagnulo, S.; Tozzi, G. P.; Boehnhardt, H.; Vincent, J.-B.; Muinonen, K.


    Context. Photometry and polarimetry have been extensively used as a diagnostic tool for characterizing the activity of comets when they approach the Sun, the surface structure of asteroids, Kuiper-Belt objects, and, more rarely, cometary nuclei. Aims: 133P/Elst-Pizarro is an object that has been described as either an active asteroid or a cometary object in the main asteroid belt. Here we present a photometric and polarimetric study of this object in an attempt to infer additional information about its origin. Methods: With the FORS1 instrument of the ESO VLT, we have performed during the 2007 apparition of 133P/Elst-Pizarro quasi-simultaneous photometry and polarimetry of its nucleus at nine epochs in the phase angle range ~ 0° - 20°. For each observing epoch, we also combined all available frames to obtain a deep image of the object, to seek signatures of weak cometary activity. Polarimetric data were analysed by means of a novel physical interference modelling. Results: The object brightness was found to be highly variable over timescales <1 h, a result fully consistent with previous studies. Using the albedo-polarization relationships for asteroids and our photometric results, we found for our target an albedo of about 0.06-0.07 and a mean radius of about 1.6 km. Throughout the observing epochs, our deep imaging of the comet detects a tail and an anti-tail. Their temporal variations are consistent with an activity profile starting around mid May 2007 of minimum duration of four months. Our images show marginal evidence of a coma around the nucleus. The overall light scattering behaviour (photometry and polarimetry) resembles most closely that of F-type asteroids. Based on observations made with ESO Telescopes at the Paranal Observatory under programme ID 079.C-0653 (PI = Tozzi).

  8. Another neon nova - Early infrared photometry and spectroscopy of Nova Cygni 1992 (United States)

    Hayward, T. L.; Gehrz, R. D.; Miles, J. W.; Houck, J. R.


    Infrared photometry and spectrophotometry of Nova Cygni 1992 taken within 54 days of its eruption show a strong 12.8-micron Ne II forbidden emission line as well as hydrogen recombination lines. Spectra with lambda/Delta lambda of about 2000 resolve the Ne II forbidden and 12.37-micron Hu-alpha lines with about 2200 km/s (FWHM). The Ne II forbidden line shows multiple velocity components. The amount of forbidden Ne II required to produce the observed emission feature exceeds the solar abundance of neon by at least a factor of 4.

  9. Rapid photometry of EZ Canis Majoris - Searching for flare activity in Wolf-Rayet stars (United States)

    Matthews, J. M.; Moffat, A. F. J.; Marchenko, S. V.


    EZ CMa was chosen for a trial run of high-speed photometry to search for flare activity in W-R stars. Data were collected during UT November 27-December 2, 1991 with the 1.0-telescope + ASCAP photometer and the 0.6-m telescope + manual photometer of the Cerro Tololo Inter-American Observatory. A period near 22.7 min was found. A brightness increase of about 1 percent, lasting for about 10 min in the otherwise smooth light curve, was observed. Fourier analysis of the data sets an upper limit of 0.0005 mag on any variations with periods less than about 10 min.

  10. Infrared photometry of the RS CVn short-period systems - XY UMa and WY Cnc

    Energy Technology Data Exchange (ETDEWEB)

    Arevalo, M.J.; Lazaro, C. (Instituto de Astrofisica de Canarias, La Laguna (Spain))


    Infrared J and K light curves of two RS CVn short-period systems, XY UMa and WY Cnc, are presented. Both systems show similar variability in the infrared to that observed in the visual. From the colors an infrared excess is inferred for the primary component of both systems. A new determination of their geometrical elements is presented and the resulting parameters are compared to those previously obtained from visible photometry. The light curves show peculiarities that may indicate the presence of gas streams in the systems. 27 refs.

  11. Photon counting imaging and centroiding with an electron-bombarded CCD using single molecule localisation software

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, Liisa M.; Barber, Matthew J.; Suhling, Klaus, E-mail:


    Photon event centroiding in photon counting imaging and single-molecule localisation in super-resolution fluorescence microscopy share many traits. Although photon event centroiding has traditionally been performed with simple single-iteration algorithms, we recently reported that iterative fitting algorithms originally developed for single-molecule localisation fluorescence microscopy work very well when applied to centroiding photon events imaged with an MCP-intensified CMOS camera. Here, we have applied these algorithms for centroiding of photon events from an electron-bombarded CCD (EBCCD). We find that centroiding algorithms based on iterative fitting of the photon events yield excellent results and allow fitting of overlapping photon events, a feature not reported before and an important aspect to facilitate an increased count rate and shorter acquisition times.

  12. CCD Astrometric Measurements of Double Stars BAL 746, BPM 342, KU 92, and STF 897 (United States)

    Smith, Schuyler


    Double stars WDS 06589-0106 (BAL 746), WDS 06579+1430 (BPM 342), WDS 07006+0921 (KU 92), and WDS 06224+2640 (STF 897) were measured as part of a science fair project for the 2016 Greater San Diego Science and Engineering Fair. The goal was to measure the separation and position angles of stars by using a telescope with a charge-coupled device (CCD) on the iTelescope network. Five images were taken of each of the stars. These images were plate solved with Visual PinPoint and measured using Aladin Sky Atlas. Measurements for all five doubles compare well to the more recent values in the Washington Double Star Catalog.

  13. Advanced CCD imager technology for use from 1 to 10,000 A (United States)

    Twichell, J. C.; Burke, B. E.; Reich, R. K.; Mcgonagle, W. H.; Huang, C. M.


    A low-noise, high-sensitivity charge-coupled-device (CCD) technology for imaging applications extending from the soft X-ray (1 A) to the near-infrared (10,000 A) regimes was developed together with a fabrication technology for making back-illuminated versions of these devices with quantum efficiencies as high as 90 percent from 5000 to 7000 A. The efforts have focused on two devices, a 64 x 64 pixel back-illuminated imager with two output ports that operates at 2000 frames per second with 23 electrons read noise, and a larger device, with 420 x 420 pixel format, designed for lower frame rates with noise as low as 1.5 electrons and used at visible, UV, and X-ray wavelengths. Applications to plasma diagnostics include Thomson scattering and high-frame-rate imaging in the visible, as well as X-ray imaging and bolometry.

  14. Observaciones CCD de los cúmulos abiertos Melotte 105, Ruprecht~75 y Pismis 7 (United States)

    Ahumada, J.; Lapasset, E.

    Se presentan los resultados preliminares de observaciones CCD en cinco colores (UBVRI) de campos de ~2,5' de radio centrados en los cúmulos abiertos Melotte 105, Ruprecht 75 y Pismis 7. Los datos fueron adquiridos en abril de 1996 con el telescopio de 60 cm de la Universidad de Toronto en Las Campanas (Chile), y el detector PM512 en su modo directo. Se muestran los diagramas color-magnitud y color-color preliminares de los cúmulos. Mediante criterios fotométricos se hace una selección de los posibles miembros. También se determinan enrojecimientos, distancias y edades de los cúmulos.

  15. Charge-coupled device /CCD/ visible light sensor for the Teal Ruby Experiment (United States)

    Roberts, A.

    The Teal Ruby Experiment (TRE), employing a Space-Shuttle-launched infrared telescope, will mark a major milestone in the application of mosaic infrared detectors in space. However, it is generally recognized that supplemental overview imagery acquired in the visible portion of the spectrum is necessary to assist in accurately interpreting the data generated by the infrared focal plane. For this purpose, the TRE will be equipped with a Charge Coupled Device (CCD) Visible Light Sensor (VLS) that will yield the cloud and ground truth data needed to assist in pointing and scene verification. The optical format of the VLS is designed to overlay the TRE footprint on the earth from a distance of 1000 nautical miles. The VLS is designed, built and will be qualified to meet the environmental and reliability requirements for an on-orbit mission in excess of one year. The TRE/VLS is tentatively scheduled for launch in mid 1983.

  16. A compact CCD-monitored atomic force microscope with optical vision and improved performances. (United States)

    Mingyue, Liu; Haijun, Zhang; Dongxian, Zhang


    A novel CCD-monitored atomic force microscope (AFM) with optical vision and improved performances has been developed. Compact optical paths are specifically devised for both tip-sample microscopic monitoring and cantilever's deflection detecting with minimized volume and optimal light-amplifying ratio. The ingeniously designed AFM probe with such optical paths enables quick and safe tip-sample approaching, convenient and effective tip-sample positioning, and high quality image scanning. An image stitching method is also developed to build a wider-range AFM image under monitoring. Experiments show that this AFM system can offer real-time optical vision for tip-sample monitoring with wide visual field and/or high lateral optical resolution by simply switching the objective; meanwhile, it has the elegant performances of nanometer resolution, high stability, and high scan speed. Furthermore, it is capable of conducting wider-range image measurement while keeping nanometer resolution. Copyright © 2013 Wiley Periodicals, Inc.

  17. CCD Video Observation of Microgravity Crystallization of Lysozyme and Correlation with Accelerometer Data (United States)

    Snell, E. H.; Boggon, T. J.; Helliwell, J. R.; Moskowitz, M. E.; Nadarajah, A.


    Lysozyme has been crystallized using the ESA Advanced Protein Crystallization Facility onboard the NASA Space Shuttle Orbiter during the IML-2 mission. CCD video monitoring was used to follow the crystallization process and evaluate the growth rate. During the mission some tetragonal crystals were observed moving over distances of up to 200 micrometers. This was correlated with microgravity disturbances caused by firings of vernier jets on the Orbiter. Growth-rate measurement of a stationary crystal (which had nucleated on the growth reactor wall) showed spurts and lulls correlated with an onboard activity; astronaut exercise. The stepped growth rates may be responsible for the residual mosaic block structure seen in crystal mosaicity and topography measurements.

  18. Soft X-ray response of a CCD with a grating spectrometer

    CERN Document Server

    Shouho, M; Katayama, H; Kohmura, T; Tsunemi, H; Kitamoto, S; Hayashida, K; Miyata, E; Hashimotodani, K; Yoshita, K; Koyama, K; Ricker, G; Bautz, M W; Foster, R; Kissel, S


    We calibrate the X-ray imaging spectrometers, which are CCD cameras installed on the ASTRO-E satellite, by using dispersed continuous soft X-rays from a grating spectrometer. We obtained the signal-pulse height and energy-resolution as a function of X-ray energies continuously. However, the wings of the line spread function of the grating distorts the center of the signal-pulse height derived by a simple analysis. An estimation of this distortion is presented. We also describe two methods of extracting the pure signal-pulse-height distribution from the data using the spectrometer. A brief description of the low-energy tail is presented.

  19. Quantum efficiency of the CCD camera (XIS) for the ASTRO-E mission

    CERN Document Server

    Katayama, H; Kohmura, T; Katayama, K; Yoshita, K; Tsunemi, H; Kitamoto, S; Hayashida, K; Miyata, E; Hashimotodani, K; Koyama, K; Ricker, G; Bautz, M W; Foster, R; Kissel, S


    We measured the optical and the X-ray transmission of the optical blocking filters for the X-ray Imaging Spectrometers (XISs) which are the X-ray CCD cameras of the ASTRO-E satellite. We conclude that the oxidation of the aluminum reduces the optical transmission down to approx 60-70% of the theoretical value of the aluminum. We achieved optical transmission below 5x10 sup - sup 5 in the range from 4000 to 9500 A by using aluminum thickness of 1200 A, while the theoretical calculation requires 800 A. The measurement of absolute quantum efficiency of XIS is also performed at several particular energies. We confirmed 20% quantum efficiency at 0.5 keV for the XIS engineering model (XIS EM).

  20. Design of a fast multi-hit position sensitive detector based on a CCD camera

    CERN Document Server

    Renaud, L; Da Costa, G; Deconihout, B


    A new position sensitive detector has been designed for time-of-flight mass spectrometry. It combines a double micro-channel plate stage with a phosphor screen, the conductive coating of which is divided into an array of strip-like-shaped anodes. Time-of-flight signals are measured on the strip array with a 0.5 ns resolution, while a CCD camera records light-spots generated by ion impacts on the phosphor screen. With this particular imaging device, it is possible to accurately assign time-of-flight to positions recorded by the camera. This paper describes the main features of this new position sensitive detector and results obtained with a three-dimensional atom probe are presented.

  1. A GPRS Based Monitoring and Management System for Classification Results of Image by CCD Camera

    Directory of Open Access Journals (Sweden)

    Cheng Kun Guo


    Full Text Available Data acquisition plays an important role in the field of modern industry. In many cases, remote data should be transferred to monitor center which is far away from the manufacturing field. This paper presents a remote transmission system for the classification results of images which are got by a CCD sensor. The utilization of web application framework gives this system the advantage of minimum research work on the monitor center. A GPRS DTU treated as an information transmitting terminal was used to transmit a custom format of the classified images. In the system, The Users can use the browser anywhere to log on the website of the system so as to view and manage the experimental stations, sensors and users’ information of the system. The results shows that the system can transmit and management the figures classified by Support Vector Machines (SVM. The figures those use other classified method will be tested in the future.

  2. Cinética e equilíbrio de adsorção dos oxiânions Cr (VI, Mo (VI e Se (VI pelo sal de amônio quaternário de quitosana Kinetics and equilibrium of adsorption of oxyanions Cr (VI, Mo (VI and Se (VI by quaternary ammonium chitosan salt

    Directory of Open Access Journals (Sweden)

    Viviane A. Spinelli


    Full Text Available O sal quaternário de quitosana foi sintetizado com cloreto de glicidil trimetil amônio. A modificação química foi caracterizada por espectrometria no IV, RMN de 13C e ¹H, e mmol/g de grupos quaternários presentes na matriz polimérica por condutimetria. A remoção de Cr (VI, Mo (VI e Se (VI, em meio aquoso, foi investigada em processo de batelada. A adsorção mostrou ser dependente do pH para o Cr (VI e Se (VI, com um pH ótimo de adsorção, entre 4,0 a 6,0. Para o Mo (VI a adsorção manteve-se quase constante no intervalo de pH entre 4,0 e 11,5. O modelo de isoterma de Langmuir descreveu melhor os dados de equilíbrio na faixa de concentração investigada. No presente estudo, um grama do sal quaternário de quitosana reticulado com glutaraldeído adsorveu 68,3 mg de Cr, 63,4 mg de Mo e 90,0 mg de Se. A velocidade de adsorção, no processo, segue a equação cinética de pseudo segunda-ordem, sendo que o equilíbrio para os três íons foi alcançado próximo aos 200 minutos. A análise dispersiva de raios-X para o Cr (VI mostrou que o principal mecanismo de adsorção é a troca iônica entre os íons Cl- da superfície do polímero pelos oxiânions. O trocador aniônico apresentou a seguinte ordem de seletividade: Cr (VI > Mo (VI > Se (VI.Quaternary chitosan salt was synthesized in the presence of glycidyl trimetyl ammonium chloride. The polymer was characterized by spectroscopic techniques: infrared, 13C and ¹H NMR, while the amount of quaternary ammonium groups was obtained by condutimetry. The removal of Cr (VI, Mo (VI and Se (VI from aqueous solutions was carried out in batch adsorption processes. The process seemed to be pH dependent for Cr (VI and Se (VI with an optimum pH ranging from 4.0 to 6.0; while for Mo (VI the adsorption remained almost constant within the range between 4.0 and 11.5. The Langmuir isotherm model provided the best fit of the equilibrium data over the whole concentration investigated. In the experiment

  3. On-ground and in-orbit characterisation plan for the PLATO CCD normal cameras (United States)

    Gow, J. P. D.; Walton, D.; Smith, A.; Hailey, M.; Curry, P.; Kennedy, T.


    PLAnetary Transits and Ocillations (PLATO) is the third European Space Agency (ESA) medium class mission in ESA's cosmic vision programme due for launch in 2026. PLATO will carry out high precision un-interrupted photometric monitoring in the visible band of large samples of bright solar-type stars. The primary mission goal is to detect and characterise terrestrial exoplanets and their systems with emphasis on planets orbiting in the habitable zone, this will be achieved using light curves to detect planetary transits. PLATO uses a novel multi- instrument concept consisting of 26 small wide field cameras The 26 cameras are made up of a telescope optical unit, four Teledyne e2v CCD270s mounted on a focal plane array and connected to a set of Front End Electronics (FEE) which provide CCD control and readout. There are 2 fast cameras with high read-out cadence (2.5 s) for magnitude ~ 4–8 stars, being developed by the German Aerospace Centre and 24 normal (N) cameras with a cadence of 25 s to monitor stars with a magnitude greater than 8. The N-FEEs are being developed at University College London's Mullard Space Science Laboratory (MSSL) and will be characterised along with the associated CCDs. The CCDs and N-FEEs will undergo rigorous on-ground characterisation and the performance of the CCDs will continue to be monitored in-orbit. This paper discusses the initial development of the experimental arrangement, test procedures and current status of the N-FEE. The parameters explored will include gain, quantum efficiency, pixel response non-uniformity, dark current and Charge Transfer Inefficiency (CTI). The current in-orbit characterisation plan is also discussed which will enable the performance of the CCDs and their associated N-FEE to be monitored during the mission, this will include measurements of CTI giving an indication of the impact of radiation damage in the CCDs.

  4. A 14-bit 40-MHz analog front end for CCD application (United States)

    Jingyu, Wang; Zhangming, Zhu; Shubin, Liu


    A 14-bit, 40-MHz analog front end (AFE) for CCD scanners is analyzed and designed. The proposed system incorporates a digitally controlled wideband variable gain amplifier (VGA) with nearly 42 dB gain range, a correlated double sampler (CDS) with programmable gain functionality, a 14-bit analog-to-digital converter and a programmable timing core. To achieve the maximum dynamic range, the VGA proposed here can linearly amplify the input signal in a gain range from -1.08 to 41.06 dB in 6.02 dB step with a constant bandwidth. A novel CDS takes image information out of noise, and further amplifies the signal accurately in a gain range from 0 to 18 dB in 0.035 dB step. A 14-bit ADC is adopted to quantify the analog signal with optimization in power and linearity. An internal timing core can provide flexible timing for CCD arrays, CDS and ADC. The proposed AFE was fabricated in SMIC 0.18 μm CMOS process. The whole circuit occupied an active area of 2.8 × 4.8 mm2 and consumed 360 mW. When the frequency of input signal is 6.069 MHz, and the sampling frequency is 40 MHz, the signal to noise and distortion (SNDR) is 70.3 dB, the effective number of bits is 11.39 bit. Project supported by the National Natural Science Foundation of China (Nos. 61234002, 61322405, 61306044, 61376033), the National High-Tech Program of China (No. 2013AA014103), and the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (No. ZHD201302).

  5. Picosecond Raman spectroscopy with a fast intensified CCD camera for depth analysis of diffusely scattering media. (United States)

    Ariese, Freek; Meuzelaar, Heleen; Kerssens, Marleen M; Buijs, Joost B; Gooijer, Cees


    A spectroscopic depth profiling approach is demonstrated for layers of non-transparent, diffusely scattering materials. The technique is based on the temporal discrimination between Raman photons emitted from the surface and Raman photons originating from a deeper layer. Excitation was carried out with a frequency-doubled, 3 ps Ti:sapphire laser system (398 nm; 76 MHz repetition rate). Time-resolved detection was carried out with an intensified CCD camera that can be gated with a 250 ps gate width. The performance of the system was assessed using 1 mm and 2 mm pathlength cuvettes with powdered PMMA and trans-stilbene (TS) crystals, respectively, or solid white polymer blocks: Arnite (polyethylene terephthalate), Delrin (polyoxymethylene), polythene (polyethylene) and Teflon (polytetrafluoroethylene). These samples were pressed together in different configurations and Raman photons were collected in backscatter mode in order to study the time difference in such media corresponding with several mm of extra net photon migration distance. We also studied the lateral contrast between two different second layers. The results demonstrate that by means of a picosecond laser system and the time discrimination of a gated intensified CCD camera, molecular spectroscopic information can be obtained through a turbid surface layer. In the case of the PMMA/TS two-layer system, time-resolved detection with a 400 ps delay improved the relative intensity of the Raman bands of the second layer with a factor of 124 in comparison with the spectrum recorded with a 100 ps delay (which is more selective for the first layer) and with a factor of 14 in comparison with a non-gated setup. Possible applications will be discussed, as well as advantages/disadvantages over other Raman techniques for diffusely scattering media.

  6. An adaptive threshold method for improving astrometry of space debris CCD images (United States)

    Sun, Rong-yu; Zhao, Chang-yin


    Optical survey is a main technique for observing space debris, and precisely measuring the positions of space debris is of great importance. Due to several factors, e.g. the angle object normal to the observer, the shape as well as the attitude of the object, the variations of observed characteristics for low earth orbital space debris are distinct. When we look at optical CCD images of observed objects, the size and brightness are varying, hence it’s difficult to decide the threshold during centroid measurement and precise astrometry. Traditionally the threshold is given empirically and constantly in data reduction, and obviously it’s not suitable for data reduction of space debris. Here we offer a solution to provide the threshold. Our method assumes that the PSF (point spread function) is Gaussian and estimates the signal flux by a directly two-dimensional Gaussian fit, then a cubic spline interpolation is performed to divide each initial pixel into several sub-pixels, at last the threshold is determined by the estimation of signal flux and the sub-pixels above threshold are separated to estimate the centroid. A trail observation of the fast spinning satellite Ajisai is made and the CCD frames are obtained to test our algorithm. The calibration precision of various threshold is obtained through the comparison between the observed equatorial position and the reference one, the latter are obtained from the precise ephemeris of the satellite. The results indicate that our method reduces the total errors of measurements, it works effectively in improving the centering precision of space debris images.

  7. In-flight absolute calibration of the CBERS-2 CCD sensor data

    Directory of Open Access Journals (Sweden)

    Flávio J. Ponzoni


    Full Text Available Since the first images of the sensors on board of CBERS-2 (China-Brazil Earth Resources Satellite satellite were made available by the National Institute for Space Research (INPE, users have asked information about the conversion of image digital numbers to physical data (radiance or reflectance. This paper describes the main steps that were carried out to calculate the in-flight absolute calibration coefficients for CBERS-2 CCD level 2 (radiometric and geometric correction images considering the reflectance-based method. Remarks about the preliminary evaluation of these coefficients application are also presented.Desde o início da distribuição de imagens dos sensores do satélite CBERS-2 (China-Brazil Earth Resources Satellite por parte do Instituto Nacional de Pesquisas Espaciais (INPE, a comunidade de usuários solicitava informação sobre a conversão dos números digitais em valores físicos (radiância ou reflectância. Este artigo descreve os principais passos adotados no cálculo dos coeficientes de calibração absoluta para as imagens disponibilizadas no nível 2 de correção (correções radiométrica e geométrica da câmera CBERS-2 CCD, considerando o método baseado na reflectância de uma superfície de referência. São apresentados também alguns resultados da avaliação preliminar da aplicação desses coeficientes na conversão mencionada.

  8. Vi behøver innovation

    DEFF Research Database (Denmark)

    McAloone, Tim C.


    . Især hvad angår vores forbrugsmønstre. Her er der behov for at kongeriget Danmark med sine 13 ton CO2-emission pr. person om året lytter. I landet hvor kraftvarmeproduk­tion, vindturbiner og industrial ecology i form af Kalundborg eksperimentet blev født, bør vi ikke også ride på denne nye miljøbølge......? Den amerikanske videnskabsmand Jeremy Rifkin beskriver i sin seneste bog, The European Dream, hvordan europæisk energipolitik, -forskning, -udvikling og relateret industri kan hjælpe os til at bremse vores for øjeblikket eksponentielt stigende CO2-produktion - og hvordan vores globaliseringstankegang...... rent faktisk kan fremme denne indsats. Den eneste udfordring er, at nogen skal igangsætte en økonomisk/industriel revolution, for at drømmen går i opfyldelse. Hvem skal tage ansvar for at sætte denne revolution i gang, og hvordan skal den opnås? Rifkin's patentløsning er inspirerende. Den er kort...

  9. [VI Symposium on "Chemistry of Proteolytic Enzymes"]. (United States)

    Rumsh, L D; Rotanova, T V


    The VI Symposium on the Chemistry of Proteolytic Enzymes took place in Moscow on April 23-25, 2007. It was dedicated to the memory of Corresponding Member of the Russian Academy of Sciences Vladimir Konstantinovich Antonov. At the symposium, 40 reports were delivered and 103 posters were presented in the following sections: (1) expression of genes, isolation and general characterization of proteases; (2) structure-function studies of proteases; (3) regulation of the activity of proteolytic enzymes; (4) regulatory functions of proteolytic enzymes; (5) proteases in biotechnology, protein engineering, and peptide synthesis; and (6) proteolysis and medicine. In addition to Russian scientists, researchers from the United States, the Netherlands, France, Ukraine, Belarus, Azerbaijan and Uzbekistan took part in the work of the symposium. Note that, in the five years since the V Symposium, the geography of Russian scientific centers working in the area of proteolysis has been considerably extended. Participating in the forum were researchers from, Novosibirsk, Tomsk, Penza, and Stavropol in addition to scientists from Moscow, Saint Petersburg, Petrozavodsk, Kazan, Nizhni Novgorod, and Krasnodar.

  10. Wind tunnel test of musi VI bridge (United States)

    Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra


    Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

  11. A Case of Aplasia Cutis Congenita Type VI: Bart Syndrome

    National Research Council Canada - National Science Library

    Yasmin Alfayez; Sahar Alsharif; Adel Santli


    Aplasia cutis congenita type VI, also known as Bart syndrome, is a rare genetic mechanobullous disorder characterized by congenital localized absence of skin, mucocutaneous blistering lesions, and nail abnormalities...

  12. Stark broadening parameter tables for F VI and Cl VII

    Directory of Open Access Journals (Sweden)

    Dimitrijević M.S.


    Full Text Available Using a semiclassical approach, we have calculated electron−, proton−, and He III−impact line widths and shifts for 2 F VI and 10 Cl VII multiplets as a function of temperature and perturber density.


    Energy Technology Data Exchange (ETDEWEB)

    A.P. Deditius; S. Utsunomiya; R.C. Ewing


    Uranium-(VI) phases are the primary alteration products of the UO{sub 2} in spent nuclear fuel and the UO{sub 2+x}, in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO{sub 2}{sup 2+} polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO{sub 2+x}, to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements.

  14. Expression and distribution of type VI collagen in gynecomastia. (United States)

    Lanzafame, S; Magro, G; Colombatti, A


    We investigated the distribution of type VI collagen in 36 cases of routinely fixed and paraffin-embedded gynecomastia using an immunoperoxidase method for light microscopic visualization. Four samples of normal male mammary gland tissue were also included as controls. A protease predigestion was essential for the visualization of this extracellular matrix (ECM) glycoprotein. In normal male breast, no immunoreaction for type VI collagen was detected in the stroma surrounding the ducts. Gynecomastia was classified into three histological types: florid (type I), fibrous (type II), and intermediate (type III). Type VI collagen was differentially expressed in the periductal stroma of all types. This collagen was markedly expressed at the early disease stage (type I) when the periductal stroma is highly cellular and vascular. Its expression decreased when periductal stroma undergoing fibrotic transformation (type III) and completely disappeared from the dense periductal stroma of fibrous stage (type II). These findings suggest that type VI collagen is involved in the ECM remodelling occurring in gynecomastia.

  15. INTELSAT VI artist concept drawing titled 'Ocean Bridge' (United States)


    International Telecommunications Satellite Organization (INTELSAT) VI artist concept drawing titled 'Ocean Bridge' shows satellite built by Hughes Aircraft Company and owned and operated by INTELSAT, a 122-nation cooperative, orbiting the Earth.

  16. Mechanism of uranium (VI) removal by two anaerobic bacterial communities

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, FCT, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Ana M. Rosa da [Centro de Investigacao em Quimica do Algarve, Universidade do Algarve, FCT, DQF, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande, 1749-016 Lisboa (Portugal); Matos, Antonio Pedro [Servico de Anatomia Patologica, Hospital Curry Cabral, Lisboa (Portugal); Costa, Maria Clara, E-mail: [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal)


    The mechanism of uranium (VI) removal by two anaerobic bacterial consortia, recovered from an uncontaminated site (consortium A) and other from an uranium mine (consortium U), was investigated. The highest efficiency of U (VI) removal by both consortia (97%) occurred at room temperature and at pH 7.2. Furthermore, it was found that U (VI) removal by consortium A occurred by enzymatic reduction and bioaccumulation, while the enzymatic process was the only mechanism involved in metal removal by consortium U. FTIR analysis suggested that after U (VI) reduction, U (IV) could be bound to carboxyl, phosphate and amide groups of bacterial cells. Phylogenetic analysis of 16S rRNA showed that community A was mainly composed by bacteria closely related to Sporotalea genus and Rhodocyclaceae family, while community U was mainly composed by bacteria related to Clostridium genus and Rhodocyclaceae family.

  17. Thermodynamical analysis of the fission product release in the ORNL VI-3 and VI-5 tests; Analyse thermodynamique du relachement des produits de fission dans les essais ORNL VI-3 et VI-5

    Energy Technology Data Exchange (ETDEWEB)

    Defoort, J.; Froment, K


    The thermodynamical equilibrium hypothesis has been applied to the tests ORNL (Oak Ridge National Laboratory) VI-3 and VI-5 (Vertical Induction heated), to study fission release products. Irradiated fuel samples were heated under oxidizing (VI-3) and reducing (VI-5) controlled atmosphere. They can be compared to the Vercors 4 and 5 tests. The thermodynamical calculus results of barium and ruthenium fission products release, agree in the lump with measures, whatever the gas phase nature. The strontium release calculus under reducing atmosphere, is largely upper than those measured and correctly evaluated under oxidizing atmosphere. These results confirm those obtained for Vercors 4 and 5 and show the interest of the select model. (A.L.B.)

  18. Quasisynthetic Photometry (United States)

    Tsymbal, V.

    The brief description of new ideas for the flux calibration of stellar spectra are presented. Described approach lets us to produce a lot of reference stars both for ground and space observations. The metodology also opens possibilities to determine the angular diameters from high resolution stellar spectra and analyze the interstellar medium in the direction of a star.

  19. VI Congrés Internacional de Conflictologia


    Planell Estany, Josep A.


    Discurs del rector de la Universitat Oberta de Catalunya, Josep A. Planell Estany, amb motiu del VI Congrés Internacional de Conflictologia. Discurso del rector de la Universitat Oberta de Catalunya, Josep A. Planell Estany, con motivo del VI Congreso Internacional de Conflictología. Speech by the president of the Universitat Oberta de Catalunya, Josep A. Planell Estany,on the occasion of the Sixth International Congress on Conflict Resolution.

  20. Hubble Space Telescope STIS Observations of GRB 000301C: CCD Imaging and Near-Ultraviolet MAMA Spectroscopy

    NARCIS (Netherlands)

    Smette, A.; Fruchter, A.S.; Gull, Th.R.; Sahu, K.C.; Petro, L.; Ferguson, H.; Rhoads, J.; Lindler, D.J.; Wijers, R.A.M.J.


    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the gamma-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R~=21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150