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Sample records for 6-m telescope description

  1. The EMCCD-Based Speckle Interferometer of the BTA 6-m Telescope: Description and First Results

    Maksimov, A F; Dyachenko, V V; Malogolovets, E V; Rastegaev, D A; Semernikov, E A

    2009-01-01

    The description is given for the speckle interferometer of the BTA 6-m telescope of the SAO RAS based on a new detector with an electron multiplication CCD. The main components of the instrument are microscope objectives, interference filters and atmospheric dispersion correction prisms. The PhotonMAX-512B CCD camera using a back-illuminated CCD97 allows up to 20 speckle images (with 512$\\times$512 pix resolution) per second storage on the hard drive. Due to high quantum efficiency (93% in the maximum at 550 nm), and high transmission of its optical elements, the new camera can be used for diffraction-limited (0.02$''$) image reconstruction of $15^{m}$ stars under good seeing conditions. The main advantages of the new system over the previous generation BTA speckle interferometer are examined.

  2. Analysis of Thermal Conditions of the 6-m BTA Telescope Elements and the Telescope Dome Space

    Emelianov, E. V.

    2015-01-01

    The results obtained using the temperature monitoring systems of the 6-m BTA telescope primary mirror, dome space, and external environment are reported. We consider the factors that affect the development of microturbulence in the near-mirror air layer and inside the dome space, variation of the telescope focal length with the temperature of its structures, variation of seeing due to temperature gradients inside the primary mirror of the 6-m telescope. The methods used in various observatori...

  3. Analysis of Thermal Conditions of the 6-m BTA Telescope Elements and the Telescope Dome Space

    Emelianov, E V

    2015-01-01

    The results obtained using the temperature monitoring systems of the 6-m BTA telescope primary mirror, dome space, and external environment are reported. We consider the factors that affect the development of microturbulence in the near-mirror air layer and inside the dome space, variation of the telescope focal length with the temperature of its structures, variation of seeing due to temperature gradients inside the primary mirror of the 6-m telescope. The methods used in various observatories for reducing microturbulence are analyzed. We formulate suggestions concerning the improvement of the temperature monitoring system currently in operation and the system of automatic adjustment of the telescope focal length to compensate the thermal drift of the focus during observations.

  4. Influence of Wind Buffeting on the 3.6 m Telescope

    Griffin, S.; Haar, S.; Walker, E.; Whiting, A.; Williams, S.

    2013-09-01

    Unsteady wind loading is the largest dynamic loading on most large ground telescopes. The maximum operational windspeed not only sets requirements on the wind load rejection performance of the mount control system but also is a significant driver for tracker error rejection. In addition, turbulence due to the wind contributes to wavefront distortion. With the recent interest in daylight imaging, introduction of a baffle that reduces background light during the day may further accentuate wind loading on the 3.6 m telescope. The initial daylight configuration of the telescope has been to operate without a baffle and to use operational constraints to avoid angles close to the sun. This configuration offers reasonable daylight performance but is susceptible to stray light that limits achievable signal-to-noise ratio. Also under test is a unique baffled configuration where the telescope is shrouded to increase target signal-to-noise ratio. Traditional baffles increase jitter and wind loading due to increased exposed area to the wind and increase wavefront distortion due to thermal gradients introduced by the baffle. The 3.6 m telescope baffle has been designed out of an opaque fabric to limit the negative impacts on jitter and wavefront distortion while increasing signal-to-noise ratio for daylight imaging. The intent of the design is to limit high frequency transmission of wind loading by the relatively compliant fabric and to allow some circulation using the fabric's porosity to limit thermal gradients. The fabric design also facilitates the extension to a deployable design, since it is relatively easy to deploy and stow compared to a traditional approach. This paper will present analytical results predicting jitter and mount control performance with and without the baffle as well as signal-to-noise ratio predictions with and without the baffle. The jitter results will use measured wind loading in conjunction with a system line-of-sight model for performance

  5. Internal Kinematics of Galaxies: 3D Spectroscopy on Russian 6m Telescope

    Moiseev, A V

    2006-01-01

    We have considered some results concerning gas and stars kinematics of nearby galaxies recently obtained on the SAO RAS 6m telescope using the panoramic spectroscopy methods. The circumnuclear regions of the galaxies were observed with integral-field spectrograph MPFS. The large-scale ionized gas kinematics was studied with the scanning Fabry-Perot interferometer (FPI) in the multi-mode focal reducer SCORPIO. The main attention is given for kinematically decoupled regions in the galaxies: bars, spirals, polar disks and rings.

  6. KMTNET: A Network of 1.6 m Wide-Field Optical Telescopes Installed at Three Southern Observatories

    Kim, Seung-Lee; Lee, Chung-Uk; Park, Byeong-Gon; Kim, Dong-Jin; Cha, Sang-Mok; Lee, Yongseok; Han, Cheongho; Chun, Moo-Young; Yuk, Insoo

    2016-02-01

    The Korea Microlensing Telescope Network (KMTNet) is a wide-field photometric system installed by the Korea Astronomy and Space Science Institute (KASI). Here, we present the overall technical specifications of the KMTNet observation system, test observation results, data transfer and image processing procedure, and finally, the KMTNet science programs. The system consists of three 1.6 m wide-field optical telescopes equipped with mosaic CCD cameras of 18k by 18k pixels. Each telescope provides a 2.0 by 2.0 square degree field of view. We have finished installing all three telescopes and cameras sequentially at the Cerro-Tololo Inter-American Observatory (CTIO) in Chile, the South African Astronomical Observatory (SAAO) in South Africa, and the Siding Spring Observatory (SSO) in Australia. This network of telescopes, which is spread over three different continents at a similar latitude of about -30 degrees, enables 24-hour continuous monitoring of targets observable in the Southern Hemisphere. The test observations showed good image quality that meets the seeing requirement of less than 1.0 arcsec in I-band. All of the observation data are transferred to the KMTNet data center at KASI via the international network communication and are processed with the KMTNet data pipeline. The primary scientific goal of the KMTNet is to discover numerous extrasolar planets toward the Galactic bulge by using the gravitational microlensing technique, especially earth-mass planets in the habitable zone. During the non-bulge season, the system is used for wide-field photometric survey science on supernovae, asteroids, and external galaxies.

  7. Ultra-narrow Negative Flare Front Observed in Helium-10830~\\AA\\ using the 1.6 m New Solar Telescope

    Xu, Yan; Ding, Mingde; Kleint, Lucia; Su, Jiangtao; Liu, Chang; Ji, Haisheng; Chae, Jongchul; Jing, Ju; Cho, Kyuhyoun; Cho, Kyungsuk; Gary, Dale; Wang, Haimin

    2016-01-01

    Solar flares are sudden flashes of brightness on the Sun and are often associated with coronal mass ejections and solar energetic particles which have adverse effects in the near Earth environment. By definition, flares are usually referred to bright features resulting from excess emission. Using the newly commissioned 1.6~m New Solar Telescope at Big Bear Solar Observatory, here we show a striking "negative" flare with a narrow, but unambiguous "dark" moving front observed in He I 10830 \\AA, which is as narrow as 340 km and is associated with distinct spectral characteristics in H-alpha and Mg II lines. Theoretically, such negative contrast in He I 10830 \\AA\\ can be produced under special circumstances, by nonthermal-electron collisions, or photoionization followed by recombination. Our discovery, made possible due to unprecedented spatial resolution, confirms the presence of the required plasma conditions and provides unique information in understanding the energy release and radiative transfer in astronomi...

  8. Ultra-Narrow Negative Flare Front Observed in Helium-10830 Å Using the1.6m New Solar Telescope

    Xu, Yan; Cao, Wenda; Ding, Mingde; Kleint, Lucia; Su, Jiangtao; Liu, Chang; Ji, Haisheng; Chae, Jongchul; Jing, Ju; Cho, Kyuhyoun; Cho, Kyung-Suk; Gary, Dale E.; Wang, Haimin

    2016-05-01

    Solar flares are sudden flashes of brightness on the Sun and are often associated with coronal mass ejections and solar energetic particles that have adverse effects on the near-Earth environment. By definition, flares are usually referred to as bright features resulting from excess emission. Using the newly commissioned 1.6-m New Solar Telescope at Big Bear Solar Observatory, we show a striking “negative” flare with a narrow but unambiguous “dark” moving front observed in He I 10830 Å, which is as narrow as 340 km and is associated with distinct spectral characteristics in Hα and Mg II lines. Theoretically, such negative contrast in He I 10830 Å can be produced under special circumstances by nonthermal electron collisions or photoionization followed by recombination. Our discovery, made possible due to unprecedented spatial resolution, confirms the presence of the required plasma conditions and provides unique information in understanding the energy release and radiative transfer in solar flares.

  9. Unprecedented Fine Structure of a Solar Flare Revealed by the 1.6~m New Solar Telescope

    Jing, Ju; Cao, Wenda; Liu, Chang; Gary, Dale; Wang, Haimin

    2016-01-01

    Solar flares signify the sudden release of magnetic energy and are sources of so called space weather. The fine structures (below 500 km) of flares are rarely observed and are accessible to only a few instruments world-wide. Here we present observation of a solar flare using exceptionally high resolution images from the 1.6~m New Solar Telescope (NST) equipped with high order adaptive optics at Big Bear Solar Observatory (BBSO). The observation reveals the process of the flare in unprecedented detail, including the flare ribbon propagating across the sunspots, coronal rain (made of condensing plasma) streaming down along the post-flare loops, and the chromosphere's response to the impact of coronal rain, showing fine-scale brightenings at the footpoints of the falling plasma. Taking advantage of the resolving power of the NST, we measure the cross-sectional widths of flare ribbons, post-flare loops and footpoint brighenings, which generally lie in the range of 80-200 km, well below the resolution of most curr...

  10. Unprecedented Fine Structure of a Solar Flare Revealed by the 1.6~m New Solar Telescope

    Jing, Ju; Xu, Yan; Cao, Wenda; Liu, Chang; Gary, Dale E.; Wang, Haimin

    2016-05-01

    Solar flares signify the sudden release of magnetic energy and are sources of so called space weather. The fine structures (below 500 km) of flares are rarely observed and are accessible to only a few instruments world-wide. Here we present observation of a solar flare using exceptionally high resolution images from the 1.6~m New Solar Telescope (NST) equipped with high order adaptive optics at Big Bear Solar Observatory (BBSO). The observation reveals the process of the flare in unprecedented detail, including the flare ribbon propagating across the sunspots, coronal rain (made of condensing plasma) streaming down along the post-flare loops, and the chromosphere's response to the impact of coronal rain, showing fine-scale brightenings at the footpoints of the falling plasma. Taking advantage of the resolving power of the NST, we measure the cross-sectional widths of flare ribbons, post-flare loops and footpoint brighenings, which generally lie in the range of 80-200 km, well below the resolution of most current instruments used for flare studies. Confining the scale of such fine structure provides an essential piece of information in modeling the energy transport mechanism of flares, which is an important issue in solar and plasma physics.

  11. Innovative and Improved Efficiency on the Design of a control System SOftware for CBSS 6m Radio Telescope using LabView in Nigeria

    EKEOMA Opara, Fidelis

    2015-08-01

    Software has been provided for controlling the antenna and selection of sources in a 6m radio telescope. In this work the most challenging aspect is the maintainance of the pointing accuracy of the final structure with pointing tolerance of about 0.0003 or 1 arcsecond. Using LabView, the voltage through the I/Q is read with a DAQ virtual instrument. The values are then calculated with the dish at its zero position, hence the control system is fully implemented and tested to work at full efficiency.

  12. InnoPOL: an EMCCD imaging polarimeter and 85-element curvature AO system on the 3.6-m AEOS telescope for cost effective polarimetric speckle suppression

    Harrington, David; Chun, Mark; Ftaclas, Christ; Gisler, Daniel; Kuhn, Jeff

    2016-01-01

    The Hokupa'a-85 curvature adaptive optics system components have been adapted to create a new AO-corrected coud\\'{e} instrument at the 3.67m Advanced Electro-Optical System (AEOS) telescope. This new AO-corrected optical path is designed to deliver an f/40 diffraction-limited focus at wavelengths longer than 800nm. A new EMCCD-based dual-beam imaging polarimeter called InnoPOL has been designed and is presently being installed behind this corrected f/40 beam. The InnoPOL system is a flexible platform for optimizing polarimetric performance using commercial solutions and for testing modulation strategies. The system is designed as a technology test and demonstration platform as the coud\\'{e} path is built using off-the-shelf components wherever possible. Models of the polarimetric performance after AO correction show that polarization modulation at rates as slow as 200Hz can cause speckle correlations in brightness and focal plane location sufficient enough to change the speckle suppression behavior of the mod...

  13. Age -- Metallicity relation in the MCs clusters (Based on observations made with the Danish 1.54 m and ESO 3.6m Telescopes at La Silla Observatory, Chile)

    Livanou, E; Kontizas, M; Nordström, B; Kontizas, E; Andersen, J; Dirsch, B; Karampelas, A

    2013-01-01

    Aims: To investigate a possible dependence between age and metallicity in the Magellanic Clouds (MCs) from a study of small open star clusters, using Str\\"{o}mgren photometry. Our goal is to trace evidence of an age metallicity relation (AMR) and correlate it with the mutual interactions of the two MCs. Our aim is also to correlate the AMR with the spatial distribution of the clusters. In the Large Magellanic Cloud (LMC), the majority of the selected clusters are young (up to 1 Gyr) and our aim is to search for an AMR at this epoch which has not been much studied. Methods: We report on results for 15 LMC and 8 Small Magellanic Cloud (SMC) clusters, scattered all over the area of these galaxies, to cover a wide spatial distribution and metallicity range. The selected LMC clusters were observed with the 1.54m Danish Telescope in Chile, using the Danish Faint Object Spectrograph and Camera (DFOSC) with a single 2kx2k CCD, whereas the SMC clusters were observed with the ESO 3.6m Telescope also in Chile with the E...

  14. Sardinia Radio Telescope: General Description, Technical Commissioning and First Light

    Bolli, P; Stringhetti, L; Orfei, A; Righini, S; Ambrosini, R; Bartolini, M; Bortolotti, C; Buffa, F; Buttu, M; Cattani, A; D'Amico, N; Deiana, G; Fara, A; Fiocchi, F; Gaudiomonte, F; Maccaferri, A; Mariotti, S; Marongiu, P; Melis, A; Migoni, C; Morsiani, M; Nanni, M; Nasyr, F; Pellizzoni, A; Pisanu, T; Poloni, M; Poppi, S; Porceddu, I; Prandoni, I; Roda, J; Roma, M; Scalambra, A; Serra, G; Trois, A; Valente, G; Vargiu, G P; Zacchiroli, G

    2016-01-01

    In the period 2012 June - 2013 October, the Sardinia Radio Telescope (SRT) went through the technical commissioning phase. The characterization involved three first-light receivers, ranging in frequency between 300MHz and 26GHz, connected to a Total Power back-end. It also tested and employed the telescope active surface installed in the main reflector of the antenna. The instrument status and performance proved to be in good agreement with the expectations in terms of surface panels alignment (at present 300 um rms to be improved with microwave holography), gain (~0.6 K/Jy in the given frequency range), pointing accuracy (5 arcsec at 22 GHz) and overall single-dish operational capabilities. Unresolved issues include the commissioning of the receiver centered at 350 MHz, which was compromised by several radio frequency interferences, and a lower-than-expected aperture efficiency for the 22-GHz receiver when pointing at low elevations. Nevertheless, the SRT, at present completing its Astronomical Validation ph...

  15. The camera of the fifth H.E.S.S. telescope. Part I: System description

    In July 2012, as the four ground-based gamma-ray telescopes of the H.E.S.S. (High Energy Stereoscopic System) array reached their tenth year of operation in Khomas Highlands, Namibia, a fifth telescope took its first data as part of the system. This new Cherenkov detector, comprising a 614.5 m2 reflector with a highly pixelized camera in its focal plane, improves the sensitivity of the current array by a factor two and extends its energy domain down to a few tens of GeV. The present part I of the paper gives a detailed description of the fifth H.E.S.S. telescope's camera, presenting the details of both the hardware and the software, emphasizing the main improvements as compared to previous H.E.S.S. camera technology

  16. The camera of the fifth H.E.S.S. telescope. Part I: System description

    Bolmont, J; Gauron, P; Ghislain, P; Goffin, C; Riveros, L Guevara; Huppert, J -F; Martineau-Huynh, O; Nayman, P; Parraud, J -M; Tavernet, J -P; Toussenel, F; Vincent, D; Vincent, P; Bertoli, W; Espigat, P; Punch, M; Besin, D; Delagnes, E; Glicenstein, J -F; Moudden, Y; Venault, P; Zaghia, H; Brunetti, L; Dubois, J-M; Fiasson, A; Geffroy, N; Monteiro, I Gomes; Journet, L; Krayzel, F; Lamanna, G; Flour, T Le; Lees, S; Lieunard, B; Maurin, G; Mugnier, P; Panazol, J-L; Prast, J; Chounet, L -M; Edy, E; Fontaine, G; Giebels, B; Hormigos, S; Khélifi, B; Manigot, P; Maritaz, P; de Naurois, M; Compin, M; Feinstein, F; Fernandez, D; Mehault, J; Rivoire, S; Royer, S; Sanguillon, M; Vasileiadis, G

    2013-01-01

    In July 2012, as the four ground-based gamma-ray telescopes of the H.E.S.S. (High Energy Stereoscopic System) array reached their tenth year of operation in Khomas Highlands, Namibia, a fifth telescope took its first data as part of the system. This new Cherenkov detector, comprising a 614.5 m$^2$ reflector with a highly pixellized camera in its focal plane, improves the sensitivity of the current array by a factor two and extends its energy domain down to a few tens of GeV. The present part I of the paper gives a detailed description of the fifth H.E.S.S. telescope's camera, presenting the details of both the hardware and the software, emphasizing the main improvements as compared to previous H.E.S.S. camera technology.

  17. The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX): Description and Early Pilot Survey Results

    Hill, G. J.; Gebhardt, K.; Komatsu, E.; Drory, N.; MacQueen, P. J.; Adams, J.(Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch, New Zealand); Blanc, G.A.; Koehler, R.; Rafal, M.; Roth, M. M.; Kelz, A.; Gronwall, C.; Ciardullo, R.; Schneider, D P

    2008-01-01

    The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) will outfit the 10 m HET with a new wide field and an array of 150 integral-field spectrographs to survey a 420 sq. deg. area in the north Galactic cap. Each fiber-coupled unit spectrograph will cover 350-550 nm, simultaneously. This instrument, called VIRUS, will produce ~34,000 spectra per exposure, and will open up the emission-line universe to large surveys for the first time. The survey will detect 0.8 million Lyman-alpha emittin...

  18. Calibration of the ZEUS 6 m tagger

    In the last period of the HERA running, data were taken with the ZEUS detector to measure directly the longitudinal structure function of the proton and to determine the total photoproduction cross section. The identification of electrons from photoproduction events, in which an electron interacts with a proton and is scattered at very small angles, is essential for both the measurements. The electrons were detected using a small electromagnetic calorimeter, the 6 m tagger, which as located near the beam pipe at ∼ 6m from the ep interaction point. A method for the calibration and reconstruction of electromagnetic showers in the 6m tagger was developed and the energy acceptance range and the resolution of the 6 m tagger was measured. Furthermore, the photon acceptance and the energy resolution of a different electromagnetic calorimeter used for the luminosity measurement at ZEUS were analyzed using the 6 m tagger. (orig.)

  19. Legacy extragalactic UV survey (LEGUS) with the Hubble space telescope. I. Survey description

    Calzetti, D.; Andrews, J. E. [Department of Astronomy, University of Massachusetts–Amherst, Amherst, MA 01003 (United States); Lee, J. C.; Sabbi, E.; Ubeda, L.; Bright, S. N.; Aloisi, A.; Brown, T. M.; Christian, C.; Cignoni, M. [Space Telescope Science Institute, Baltimore, MD (United States); Adamo, A. [Department of Astronomy, The Oskar Klein Centre, Stockholm University, Stockholm (Sweden); Smith, L. J. [European Space Agency/Space Telescope Science Institute, Baltimore, MD (United States); Thilker, D. [Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD (United States); Chandar, R. [Department of Physics and Astronomy, University of Toledo, Toledo, OH (United States); Clayton, G. C. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA (United States); Silva, R. da [Department of Astronomy and Astrophysics, University of California—Santa Cruz, Santa Cruz, CA (United States); Mink, S. E. de [Astronomical Institute Anton Pannekoek, Amsterdam University, Amsterdam (Netherlands); Dobbs, C. [School of Physics and Astronomy, University of Exeter, Exeter (United Kingdom); Elmegreen, B. G. [IBM Research Division, T. J. Watson Research Center, Yorktown Heights, NY (United States); Elmegreen, D. M., E-mail: calzetti@astro.umass.edu [Department of Physics and Astronomy, Vassar College, Poughkeepsie, NY (United States); and others

    2015-02-01

    The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope aimed at the investigation of star formation and its relation with galactic environment in nearby galaxies, from the scales of individual stars to those of ∼kiloparsec-size clustered structures. Five-band imaging from the near-ultraviolet to the I band with the Wide-Field Camera 3 (WFC3), plus parallel optical imaging with the Advanced Camera for Surveys (ACS), is being collected for selected pointings of 50 galaxies within the local 12 Mpc. The filters used for the observations with the WFC3 are F275W(λ2704 Å), F336W(λ3355 Å), F438W(λ4325 Å), F555W(λ5308 Å), and F814W(λ8024 Å); the parallel observations with the ACS use the filters F435W(λ4328 Å), F606W(λ5921 Å), and F814W(λ8057 Å). The multiband images are yielding accurate recent (≲50 Myr) star formation histories from resolved massive stars and the extinction-corrected ages and masses of star clusters and associations. The extensive inventories of massive stars and clustered systems will be used to investigate the spatial and temporal evolution of star formation within galaxies. This will, in turn, inform theories of galaxy evolution and improve the understanding of the physical underpinning of the gas–star formation relation and the nature of star formation at high redshift. This paper describes the survey, its goals and observational strategy, and the initial scientific results. Because LEGUS will provide a reference survey and a foundation for future observations with the James Webb Space Telescope and with ALMA, a large number of data products are planned for delivery to the community.

  20. Legacy extragalactic UV survey (LEGUS) with the Hubble space telescope. I. Survey description

    The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope aimed at the investigation of star formation and its relation with galactic environment in nearby galaxies, from the scales of individual stars to those of ∼kiloparsec-size clustered structures. Five-band imaging from the near-ultraviolet to the I band with the Wide-Field Camera 3 (WFC3), plus parallel optical imaging with the Advanced Camera for Surveys (ACS), is being collected for selected pointings of 50 galaxies within the local 12 Mpc. The filters used for the observations with the WFC3 are F275W(λ2704 Å), F336W(λ3355 Å), F438W(λ4325 Å), F555W(λ5308 Å), and F814W(λ8024 Å); the parallel observations with the ACS use the filters F435W(λ4328 Å), F606W(λ5921 Å), and F814W(λ8057 Å). The multiband images are yielding accurate recent (≲50 Myr) star formation histories from resolved massive stars and the extinction-corrected ages and masses of star clusters and associations. The extensive inventories of massive stars and clustered systems will be used to investigate the spatial and temporal evolution of star formation within galaxies. This will, in turn, inform theories of galaxy evolution and improve the understanding of the physical underpinning of the gas–star formation relation and the nature of star formation at high redshift. This paper describes the survey, its goals and observational strategy, and the initial scientific results. Because LEGUS will provide a reference survey and a foundation for future observations with the James Webb Space Telescope and with ALMA, a large number of data products are planned for delivery to the community.

  1. The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX): Description and Early Pilot Survey Results

    Hill, G J; Komatsu, E; Drory, N; MacQueen, P J; Adams, J; Blanc, G A; Köhler, R; Rafal, M; Roth, M M; Kelz, A; Gronwall, C; Ciardullo, R; Schneider, D P

    2008-01-01

    The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) will outfit the 10 m HET with a new wide field and an array of 150 integral-field spectrographs to survey a 420 sq. deg. area in the north Galactic cap. Each fiber-coupled unit spectrograph will cover 350-550 nm, simultaneously. This instrument, called VIRUS, will produce ~34,000 spectra per exposure, and will open up the emission-line universe to large surveys for the first time. The survey will detect 0.8 million Lyman-alpha emitting (LAE) galaxies with 1.9

  2. Legacy ExtraGalactic UV Survey (LEGUS) with The Hubble Space Telescope. I. Survey Description

    Calzetti, D; Sabbi, E; Adamo, A; Smith, L J; Andrews, J E; Ubeda, L; Bright, S N; Thilker, D; Aloisi, A; Brown, T M; Chandar, R; Christian, C; Cignoni, M; Clayton, G C; da Silva, R; de Mink, S E; Dobbs, C; Elmegreen, B G; Elmegreen, D M; Evans, A S; Fumagalli, M; Gallagher, J S; Gouliermis, D A; Grebel, E K; Herrero, A; Hunter, D A; Johnson, K E; Kennicutt, R C; Kim, H; Krumholz, M R; Lennon, D; Levay, K; Martin, C; Nair, P; Nota, A; Oestlin, G; Pellerin, A; Prieto, J; Regan, M W; Ryon, J E; Schaerer, D; Schiminovich, D; Tosi, M; Van Dyk, S D; Walterbos, R; Whitmore, B C; Wofford, A; .,

    2014-01-01

    The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope, aimed at the investigation of star formation and its relation with galactic environment in nearby galaxies, from the scales of individual stars to those of ~kpc-size clustered structures. Five-band imaging, from the near-ultraviolet to the I-band, with the Wide Field Camera 3, plus parallel optical imaging with the Advanced Camera for Surveys, is being collected for selected pointings of 50 galaxies within the local 12 Mpc. The filters used for the observations with the Wide Field Camera 3 are: F275W(2,704 A), F336W(3,355 A), F438W(4,325 A), F555W(5,308 A), and F814W(8,024 A); the parallel observations with the Advanced Camera for Surveys use the filters: F435W(4,328 A), F606W(5,921 A), and F814W(8,057 A). The multi-band images are yielding accurate recent (<~50 Myr) star formation histories from resolved massive stars and the extinction-corrected ages and masses of star clusters and associations. The e...

  3. The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX): Description and Early Pilot Survey Results

    Hill, G. J.; Gebhardt, K.; Komatsu, E.; Drory, N.; MacQueen, P. J.; Adams, J.; Blanc, G. A.; Koehler, R.; Rafal, M.; Roth, M. M.; Kelz, A.; Gronwall, C.; Ciardullo, R.; Schneider, D. P.

    2008-10-01

    The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) will outfit the 10 m HET with a new wide field and an array of 150 integral-field spectrographs to survey a 420 deg^2 area in the north Galactic cap. Each fiber-coupled unit spectrograph will cover 350-550 nm, simultaneously. This instrument, called VIRUS, will produce ˜34,000 spectra per exposure, and will open up the emission-line universe to large surveys for the first time. The survey will detect 0.8 million Lyman-alpha emitting (LAE) galaxies with 1.9

  4. 0.6-M Antennae for the Amiba Interferometry Array

    Koch, P.; Raffin, P. A.; Proty Wu, J.-H.; et al.

    2006-10-01

    The Array for Microwave Background Anisotropy (AMiBA) is a hexapod telescope for astronomy. The fully steerable platform can accommodate up to 19 dishes. We present the design, simulation, manufacturing and performance verification for the 0.6m Cassegrain antennae. The primary and secondary mirrors are carbon fiber sandwich structures, manufactured by CoTec Inc., in Taichung, Taiwan. They are aluminium coated with a final surface rms of 20-30 and 10 μm, respectively. Simulated load conditions for the mirrors show maximum rms surface errors of less than 10 μm. The measured antenna beam pattern confirms the expected performance.

  5. The OFP-6M transport jet

    Alexander, Kelly; Heneghan, Brian; Holmes, Joules; Hughes, Bret; Kettering, Mark; Wells, Jennifer; Whelan, Todd

    1994-01-01

    This report presents a preliminary design of a commercial jet transport that meets the criteria of the Request For Proposal presented by the American Institute of Aeronautics and Astronauts (AIAA). The proposal requires an innovative design of a low cost domestic commercial transport that will reduce operating costs for airline companies while still meeting present and future requirements of the Federal Aviation Regulations for this type of aircraft. Specifications for the design include a mixed class, 153 passenger aircraft, traveling a range of 3000 nm. The intent of the project is to identify factors that reduce cost and to design within the limits of these constraints. The project includes techniques or options that incorporate new technologies but do not override practicality, alternative design approaches, and a comparison between the new design and current aircraft in its class. The OFP-6M is an alternative design approach to the conventional commercial transport jet and is geared towards customer satisfaction through efficiency and reliability. The goals of the OFP-6M transport design are to provide original, sensible, and practical solutions by combining essential preliminary design factors with growing technology. The design focus of the OFP-6M reduces costs by simplifying systems where significant weight or maintenance savings can be achieved, and by integrating advanced technology for improved performance. Key aspects of the OFP-6M design are efficient use of materials like composites, and efficient advanced ducted high bypass turbofan engines. The high bypass engines lower fuel consumption and aid in reducing costs and meeting future noise emission restrictions. Composites are used for most structural components, including flooring and wing box. Although composites are an emerging technology and presently, a high maintenance material, they can be cost effective and an alternative to aluminum structures when correct manufacturing and design strategies

  6. ElevationSlope_SLOPE1p6M

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Addison County 2012 1.6m; Missisquoi Upper 2010 1.6m; Missisquoi Lower 2008 1.6m and related SLOPE...

  7. ElevationDEM_DEM1p6M

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Addison County 2012 1.6m; Missisquoi Upper 2010 1.6m; Missisquoi Lower 2008 1.6m and Digital Elevation...

  8. IR Spectrometer Project for the BTA Telescope

    Afanasiev, V.L.; Emelianov, E. V.; Murzin, V. A.; Vdovin, V. F.

    2013-01-01

    We introduce a project of new cooled infrared spectrometer-photometer for 6-m telescope BTA (Special Astrophysical Observatory of Russian Science Academy). The device would extend the wavelength range accessible for observations on the 6-m BTA telescope toward near infrared (0.8-2.5 um).

  9. The Allen Telescope Array Pi GHz Sky Survey I. Survey Description and Static Catalog Results for the Bootes Field

    Bower, Geoffrey C; Keating, Garrett; Whysong, David; Ackermann, Rob; Atkinson, Shannon; Backer, Don; Backus, Peter; Barott, Billy; Bauermeister, Amber; Blitz, Leo; Bock, Douglas; Bradford, Tucker; Cheng, Calvin; Cork, Chris; Davis, Mike; DeBoer, Dave; Dexter, Matt; Dreher, John; Engargiola, Greg; Fields, Ed; Fleming, Matt; Forster, R James; Gutierrez-Kraybill, Colby; Harp, G R; Heiles, Carl; Helfer, Tamara; Hull, Chat; Jordan, Jane; Jorgensen, Susanne; Kilsdonk, Tom; Law, Casey; van Leeuwen, Joeri; Lugten, John; MacMahon, Dave; McMahon, Peter; Milgrome, Oren; Pierson, Tom; Randall, Karen; Ross, John; Shostak, Seth; Siemion, Andrew; Smolek, Ken; Tarter, Jill; Thornton, Douglas; Urry, Lynn; Vitouchkine, Artyom; Wadefalk, Niklas; Weinreb, Sandy; Welch, Jack; Werthimer, Dan; Williams, Peter K G; Wright, Melvyn

    2010-01-01

    The Pi GHz Sky Survey (PiGSS) is a key project of the Allen Telescope Array. PiGSS is a 3.1 GHz survey of radio continuum emission in the extragalactic sky with an emphasis on synoptic observations that measure the static and time-variable properties of the sky. During the 2.5-year campaign, PiGSS will twice observe ~250,000 radio sources in the 10,000 deg^2 region of the sky with b > 30 deg to an rms sensitivity of ~1 mJy. Additionally, sub-regions of the sky will be observed multiple times to characterize variability on time scales of days to years. We present here observations of a 10 deg^2 region in the Bootes constellation overlapping the NOAO Deep Wide Field Survey field. The PiGSS image was constructed from 75 daily observations distributed over a 4-month period and has an rms flux density between 200 and 250 microJy. This represents a deeper image by a factor of 4 to 8 than we will achieve over the entire 10,000 deg^2. We provide flux densities, source sizes, and spectral indices for the 425 sources d...

  10. ElevationSlope_SLOPE1p6M2010

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Upper 2010 1.6m and related SLOPE datasets. Created using ArcGIS "SLOPE" command to produce...

  11. ElevationDEM_DEM1p6M2008

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Lower 2008 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  12. ElevationDEM_DEM1p6M2010

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Upper 2010 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  13. ElevationDEM_DEM1p6M2012

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Addison County 2012 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  14. Instrumental facilities of the 6 m telescope as of October 1994.

    Galazutdinov, G. A.; Klochkova, V. G.; Shtol', V. G.; Najdenov, I. D.; Neizvestnyj, S. I.; Plokhotnichenko, V. L.; Kopylov, A. I.; Burenkov, A. I.; Vlasyuk, V. V.; Afanas'ev, V. L.; Maximov, A. F.; Bychkov, V. D.

    Contents: 1. Echelle-spectrometer of moderate resolution (ZEBRA). 2. Echelle-spectrometer for the red wavelength range (LYNX). 3. Hydrogen-line magnetometer-spectropolarimeter. 4. Magnetometer with a Fabry-Perot interferometer. 5. Spectrophotometric system in the Nasmyth-1 focus. 6. Multichannel analyser of intensity variations - MANIA. 7. CCD camera for direct imaging. 8. Fast long-slit spectrograph (FS). 9. Multi-object fibre spectrograph (MOFS) - MEDUZA. 10. Multi-pupil field spectrograph (MPFS). 11. Digital speckle interferometer. 12. Polarimeter "MINIPOL".

  15. FRAM—The Robotic Telescope for the Monitoring of the Wavelength Dependence of the Extinction: Description of Hardware, Data Analysis, and Results

    Michael Prouza; Martin Jelínek; Petr Kubánek; Jan Ebr; Petr Trávníček; Radomír Šmída

    2010-01-01

    FRAM—F/(Ph)otometric Robotic Atmospheric Monitor is one of the atmospheric monitoring instruments at the Pierre Auger Observatory in Argentina. FRAM is an optical telescope equipped with CCD cameras and photometer, and it automatically observes a set of selected standard stars. Primarily, FRAM observations are used to obtain the wavelength dependence of the light extinction. FRAM telescope is also able to observe secondary astronomical targets, and namely the detection of optical ...

  16. Drop Tests of 325 Pound 6M Specification Packages

    Testing of 6M specification packages, performed in response to concerns over the integrity of the clamp-ring closure, showed that the clamp-ring was unable to retain the top in thirty foot drop tests of packages having the maximum allowed weight (290 kg or 640 lb). To determine if the clamp-ring closure was adequate for packages with lower contents weight, a series of tests were performed on packages weighing 147 kg (325 lb) at a range of impact angles. The results showed that the standard clamp-ring closure was unable to retain the top in tests of standard 6M packages weighing 147 kg (325 lb). A test employing a plywood disk enhanced closure with impact at 6.5 degrees retained its top successfully

  17. Space Telescope.

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    This pamphlet describes the Space Telescope, an unmanned multi-purpose telescope observatory planned for launch into orbit by the Space Shuttle in the 1980s. The unique capabilities of this telescope are detailed, the major elements of the telescope are described, and its proposed mission operations are outlined. (CS)

  18. Observatory wins GBP 10.6m contract

    Dalton, A W

    2003-01-01

    Funding has been secured for a revolutionary GBP 10.6 million telescope camera, SCUBA 2, to be built in Edinburgh. The instrument will be able to track much larger areas of sky more quickly and will replace the original Sub-millimetre Common User Bolometer Array camera which was also built in Edinburgh (1/2 page).

  19. Neutrino telescopes

    Carr, J

    2002-01-01

    This review presents the scientific objectives and status of Neutrino Telescope Projects. The science program of these projects covers: neutrino astronomy, dark matter searches and measurements of neutrino oscillations. The two neutrino telescopes in operation: AMANDA and BAIKAL will be described together with the ANTARES neutrino telescope being built in the Mediterranean. (18 refs).

  20. Drop Tests for the 6M Specification Package Closure Investigation

    Results of tests of drum-type RAM packages employing conventional clamp-ring closures have caused concern within the DOE Complex over the Department of Transportation 6M Specification Package. To clarify these issues, the Savannah River Site's Radioactive Material Packaging Technology Group was commissioned to conduct a series of tests to determine the response of the clamp-ring closure to the regulatory Hypothetical Accident Condition drop tests, for packages at maximum allowable weight, 640 lb. Additionally, three enhanced closure designs were also tested: the Clamshell, plywood disk reinforcement, and J-Clip. The results of the tests showed that the standard closure was unable to retain its lid for both Center-of-Gravity-Over-Corner and Shallow-Angle cases, for the standard package, at its maximum allowed weight. Similar results were found for packages dropped from a reduced height. The Clamshell design provided the best performance of the enhanced closures

  1. The VATLY radio telescope

    A small radio telescope (SRT) has been installed on the roof of the Hanoi astrophysics laboratory VATLY. It is equipped with a 2.6 m diameter mobile parabolic dish remotely controlled in elevation and azimuth and with super-heterodyne detection around the 21 cm hydrogen line. First results of observations of the Sun and of the centre of the Milky Way are presented. They demonstrate the high quality of the telescope performance and are used to evaluate lobe size, signal to noise ratios, anthropogenic interferences and measurement accuracies. Particular attention is given to the measurement of the pointing accuracy. The rich measurement programme that is now at hand is briefly sketched. (author)

  2. Robotic and Survey Telescopes

    Woźniak, Przemysław

    Robotic telescopes are revolutionizing the way astronomers collect their dataand conduct sky surveys. This chapter begins with a discussion of principles thatguide the process of designing, constructing, and operating telescopes andobservatories that offer a varying degree of automation, from instruments remotelycontrolled by observers to fully autonomous systems requiring no humansupervision during their normal operations. Emphasis is placed on designtrade-offs involved in building end-to-end systems intended for a wide range ofscience applications. The second part of the chapter contains descriptions ofseveral projects and instruments, both existing and currently under development.It is an attempt to provide a representative selection of actual systems thatillustrates state of the art in technology, as well as important ideas and milestonesin the development of the field. The list of presented instruments spans the fullrange in size starting from small all-sky monitors, through midrange robotic andsurvey telescopes, and finishing with large robotic instruments and surveys.Explosive growth of telescope networking is enabling entirely new modesof interaction between the survey and follow-up observing. Increasingimportance of standardized communication protocols and software is stressed.These developments are driven by the fusion of robotic telescope hardware,massive storage and databases, real-time knowledge extraction, and datacross-correlation on a global scale. The chapter concludes with examplesof major science results enabled by these new technologies and futureprospects.

  3. Space Telescopes

    Rigby, Jane R.

    2011-01-01

    The science of astronomy depends on modern-day temples called telescopes. Astronomers make pilgrimages to remote mountaintops where these large, intricate, precise machines gather light that rains down from the Universe. Bit, since Earth is a bright, turbulent planet, our finest telescopes are those that have been launched into the dark stillness of space. These space telescopes, named after heroes of astronomy (Hubble, Chandra, Spitzer, Herschel), are some of the best ideas our species has ever had. They show us, over 13 billion years of cosmic history, how galaxies and quasars evolve. They study planets orbiting other stars. They've helped us determine that 95% of the Universe is of unknown composition. In short, they tell us about our place in the Universe. The next step in this journey is the James Webb Space Telescope, being built by NASA, Europe, and Canada for a 2018 launch; Webb will reveal the first galaxies that ever formed.

  4. SNAP telescope

    Lampton, Michael L.; Akerlof, C.W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Bercovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers Jr., W.C.; Commins, E.D.; Day, C.; Deustua, S.E.; DiGennaro, R.; Ealet, A.; Ellis,R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar,A.; Groom, D.; Harris, S.E.; Harvey, P.R.; Heetderks, H.D.; Holland,S.E.; Huterer, D.; Karcher, A.; Kim, A.G.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, M.E.; Levin, D.S.; Linder, E.V.; Loken,S.C.; Malina, R.; Massey, R.; McKay, T.; McKee, S.P.; Miquel, R.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi,H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto,E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tarle, G.; Tomasch,A.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, G.; Wang, G.

    2002-07-29

    The SuperNova/Acceleration Probe (SNAP) mission will require a two-meter class telescope delivering diffraction limited images spanning a one degree field in the visible and near infrared wavelength regime. This requirement, equivalent to nearly one billion pixel resolution, places stringent demands on its optical system in terms of field flatness, image quality, and freedom from chromatic aberration. We discuss the advantages of annular-field three-mirror anastigmat (TMA) telescopes for applications such as SNAP, and describe the features of the specific optical configuration that we have baselined for the SNAP mission. We discuss the mechanical design and choice of materials for the telescope. Then we present detailed ray traces and diffraction calculations for our baseline optical design. We briefly discuss stray light and tolerance issues, and present a preliminary wavefront error budget for the SNAP Telescope. We conclude by describing some of tasks to be carried out during the upcoming SNAP research and development phase.

  5. Quantum telescopes

    Kellerer, Aglae

    2014-01-01

    In the 20th century, quantum mechanics connected the particle and wave concepts of light and thereby made mechanisms accessible that had never been imagined before. Processes such as stimulated emission and quantum entanglement have revolutionized modern technology. But even though astronomical observations rely on novel technologies, the optical layout of telescopes has fundamentally remained unchanged. While there is no doubt that Huyghens and Newton would be astounded by the size of our modern telescopes, they would nevertheless understand their optical design. The time may now have come to consider quantum telescopes, that make use of the fundamental scientific changes brought along by quantum mechanics. While one aim is to entertain our reader, our main purpose is to explore the possible future evolution of telescopes.

  6. HARPS3 for a Roboticized Isaac Newton Telescope

    Thompson, Samantha J; Baraffe, Isabelle; Brake, Martyn; Dolgopolov, Andrey; Fisher, Martin; Fleury, Michel; Geelhoed, Joost; Hall, Richard; Hernandez, Jonay I Gonzalez; ter Horst, Rik; Kragt, Jan; Navarro, Ramon; Naylor, Tim; Pepe, Francesco; Piskunov, Nikolai; Rebolo, Rafael; Sander, Louis; Segransan, Damien; Seneta, Eugene; Sing, David; Snellen, Ignas; Snik, Frans; Spronck, Julien; Stempels, Eric; Sun, Xiaowei; Tschudi, Samuel Santana; Young, John

    2016-01-01

    We present a description of a new instrument development, HARPS3, planned to be installed on an upgraded and roboticized Isaac Newton Telescope by end-2018. HARPS3 will be a high resolution (R = 115,000) echelle spectrograph with a wavelength range from 380-690 nm. It is being built as part of the Terra Hunting Experiment - a future 10 year radial velocity measurement programme to discover Earth-like exoplanets. The instrument design is based on the successful HARPS spectrograph on the 3.6m ESO telescope and HARPS-N on the TNG telescope. The main changes to the design in HARPS3 will be: a customised fibre adapter at the Cassegrain focus providing a stabilised beam feed and on-sky fibre diameter ~ 1.4 arcsec, the implementation of a new continuous flow cryostat to keep the CCD temperature very stable, detailed characterisation of the HARPS3 CCD to map the effective pixel positions and thus provide an improved accuracy wavelength solution, an optimised integrated polarimeter and the instrument integrated into a...

  7. VST telescope dynamic analisys and position control algorithms

    Schipani, P.; Mancini, D.

    2001-01-01

    The VST (VLT Survey Telescope) is a 2.6 m class Alt-Az telescope to be installed on Cerro Paranal in the Atacama desert, Northern Chile, in the European Southern Observatory (ESO) site. The VST is a wide-field imaging facility planned to supply databases for the ESO Very Large Telescope (VLT) science and carry out stand-alone observations in the UV to I spectral range. So far no telescope has been dedicated entirely to surveys; the VST will be the first survey telescope to start the operation...

  8. The Robotic Super-LOTIS Telescope: Results & Future Plans

    Williams, G. G.; Milne, P. A.; Park, H. S.; Barthelmy, S. D.; Hartmann, D. H.; Updike, A.; Hurley, K.

    2008-01-01

    We provide an overview of the robotic Super-LOTIS (Livermore Optical Transient Imaging System) telescope and present results from gamma-ray burst (GRB) afterglow observations using Super-LOTIS and other Steward Observatory telescopes. The 0.6-m Super-LOTIS telescope is a fully robotic system dedicated to the measurement of prompt and early time optical emission from GRBs. The system began routine operations from its Steward Observatory site atop Kitt Peak in April 2000 and currently operates ...

  9. The Robotic Super-LOTIS Telescope: Results & Future Plans

    Williams, G. G.; Milne, P. A.; Park, H. S.; Barthelmy, S. D.; Hartmann, D. H.; Updike, A.; Hurley, K.

    2008-05-01

    We provide an overview of the robotic Super-LOTIS (Livermore Optical Transient Imaging System) telescope and present results from gamma-ray burst (GRB) afterglow observations using Super-LOTIS and other Steward Observatory telescopes. The 0.6-m Super-LOTIS telescope is a fully robotic system dedicated to the measurement of prompt and early time optical emission from GRBs. The system began routine operations from its Steward Observatory site atop Kitt Peak in April 2000 and currently operates every clear night. The telescope is instrumented with an optical CCD camera and a four position filter wheel. It is capable of observing Swift Burst Alert Telescope (BAT) error boxes as early or earlier than the Swift UV/Optical Telescope (UVOT). Super-LOTIS complements the UVOT observations by providing early R- and I-band imaging. We also use the suite of Steward Observatory telescopes including the 1.6-m Kuiper, the 2.3-m Bok, the 6.5-m MMT, and the 8.4-m Large Binocular Telescope to perform follow-up optical and near infrared observations of GRB afterglows. These follow-up observations have traditionally required human intervention but we are currently working to automate the 1.6-m Kuiper telescope to minimize its response time.

  10. NRO 10-m submillimeter telescope

    Ukita, Nobuharu; Kawabe, Ryohei; Ishiguro, Masato; Ezawa, Hajime; Sekimoto, Yutaro; Hasegawa, Tatsuo; Yamamoto, Satoshi; Miyawaki, Keizo; Matsumoto, Soichi

    2000-07-01

    A 10-m submillimeter telescope designed for interferometric observations at bands from 3 to 0.3 mm has constructed at Nobeyama Radio Observatory. The telescope is an engineering model for a large millimeter and sub-millimeter array, and will be operated for developments of sub-millimeter observation techniques at a remote site. We have fabricated lightweight machined aluminum panels (15 kg m-2) that have a surface accuracy of 5 micrometer rms. They have a typical size of 0.8 m X 0.6 m, and are supported with three motorized screws. The back-up structure is constructed of a central hub of low thermal expansion alloy, and CFRP honeycomb boards and tubes. Holography measurements will be made with a nearby transmitter at 3 mm. The overall surface accuracy is expected to be telescope of 10-cm diameter mounted on the center hub will be used to characterize pointing and tracking accuracy. Thermal effects on the pointing and surface accuracy will be investigated using temperature measurements and FEM analyses. The fast position switching capability is also demanded to cancel atmospheric fluctuations. The antenna is able to drive both axes at a maximum velocity of 3 deg s-2 with a maximum acceleration of 6 deg. s-2. The telescope is currently equipped with SIS receivers for 100, 150, 230, and 345 GHz and a continuum backend and an FX-type digital autocorrelator with an instantaneous bandwidth of 512 MHz and 1024 channel outputs.

  11. Autonomous Dome for Robotic Telescope

    Kumar, Akash; Ganesh, Shashikiran

    2016-01-01

    Physical Research Laboratory operates a 50cm robotic observatory at Mount Abu. This Automated Telescope for Variability Studies (ATVS) makes use of Remote Telescope System 2 (RTS2) for autonomous operations. The observatory uses a 3.5m dome from Sirius Observatories. We have developed electronics using Arduino electronic circuit boards with home grown logic and software to control the dome operations. We are in the process of completing the drivers to link our Arduino based dome controller with RTS2. This document is a short description of the various phases of the development and their integration to achieve the required objective.

  12. Optical measurements with high spectral resolution on HT-6M tokamak

    The principle and technique of high-resolution optical measurement on HT-6M tokamak with a scanning Fabry-Perot interferometer is described. Applications of the techniques on HT-6M tokamak, including measurement of H/H + D ratio for determining the energy absorption mechanism of ICRH, ion temperature from line broadening and recycling of edge plasma, are reported. (6 figs., 1 tab.)

  13. A review of the safety features of 6M packagings for DOE programs

    This report, prepared by a US Department of Energy (DOE) Task Force and organized for clarity into two-page modules, argues that the US Department of Transportation (DOT) Specification-6M packagings (hereafter referred to as 6M packaging, or simply 6M) merit continued DOE use and, if necessary, DOE certification. This report is designed to address the specific requirements of a Safety Analysis Report for Packaging (SARP). While not a SARP, this report constitutes a compilation of all available documentation on 6M packagings. The authors individually, and the Task Force collectively, believe their investigation provides justification for the continued use of 6M packagings because they meet criteria for quality assurance and for safety under normal and accident conditions as defined by the US Nuclear Regulatory Commission (NRC) regulations. This report may be used by DOE managers to assist in deliberations on future requirements for 6M packagings as they are required to support DOE programs. For the purpose of ready evaluation, this report includes categorical topics found in Nuclear Regulatory Guide 7.9, the topical guideline for SARPs. The format, however, will (it is hoped) pleasantly surprise customary reader expectations. For, while maintaining categorical headings and subheadings found in SARPs as a skeleton, the Task Force chose to adopt the document design principles developed by Hughes Aircraft in the 1960s, ''Sequential Thematic Organization of Publications'' (STOP). 37 figs

  14. Bonding and magnetism in nanosized graphene molecules: Singlet states of zigzag edged hexangulenes C6m2H6m(m =2,3,…,10)

    Philpott, Michael R.; Kawazoe, Yoshiyuki

    2009-12-01

    A novel molecular phenomenon is predicted on the basis of trends identified in an ab initio density functional theory study of the electronic and geometric structure of the hexagonal shaped zigzag edged graphene hydrocarbon molecules C6m2H6m(m =2,…,10). Electrons in the interior organize to form a graphene core that grows with edge size m. Electrons in the highest occupied molecular orbital levels, localized primarily on the perimeter carbons, polarize the interior atoms with a intensity that decays rapidly with distance from the perimeter. Three distinctive bond length patterns emerge: (i) a central graphene core that grows with size m; (ii) shape-similar transverse and radial bond length patterns on interior rows close to the edges; and (iii) quinoidal bonds radiating from each apex that link adjacent edges. Concomitant with these changes are: (i) a monotonic decrease in atomic charge from center to perimeter and (ii) relegation of spin in diradical states to the outer atomic rows of the bipartite lattice.

  15. Bonding and magnetism in nanosized graphene molecules: Singlet states of zigzag edged hexangulenes C(6m(2) )H(6m)(m=2,3,...,10).

    Philpott, Michael R; Kawazoe, Yoshiyuki

    2009-12-01

    A novel molecular phenomenon is predicted on the basis of trends identified in an ab initio density functional theory study of the electronic and geometric structure of the hexagonal shaped zigzag edged graphene hydrocarbon molecules C(6m(2) )H(6m)(m=2,...,10). Electrons in the interior organize to form a graphene core that grows with edge size m. Electrons in the highest occupied molecular orbital levels, localized primarily on the perimeter carbons, polarize the interior atoms with a intensity that decays rapidly with distance from the perimeter. Three distinctive bond length patterns emerge: (i) a central graphene core that grows with size m; (ii) shape-similar transverse and radial bond length patterns on interior rows close to the edges; and (iii) quinoidal bonds radiating from each apex that link adjacent edges. Concomitant with these changes are: (i) a monotonic decrease in atomic charge from center to perimeter and (ii) relegation of spin in diradical states to the outer atomic rows of the bipartite lattice. PMID:19968359

  16. The Experiment of Modulated Toroidal Current on HT-7 and HT-6M Tokamak

    2003-01-01

    The Experiments of Modulated Toroidal Current were done on the HT-6M tokamakand HT-7 superconducting tokamak. The toroidal current was modulated by programming theOhmic heating field. Modulation of the plasma current has been used successfully to suppressMHD activity in discharges near the density limit where large MHD m = 2 tearing modes weresuppressed by sufficiently large plasma current oscillations. The improved Ohmic confinementphase was observed during modulating toroidal current (MTC) on the Hefei Tokamak-6M (HT-6M) and Hefei superconducting Tokamak-7 (HT-7). A toroidal frequency-modulated current,induced by a modulated loop voltage, was added on the plasma equilibrium current. The ratio ofA.C. amplitude of plasma current to the main plasma current △Ip/Ip is about 12% ~ 30%. Thedifferent formats of the frequency-modulated toroidal current were compared.

  17. Development and tests of interferometry facility in 6-m diameter radiometer thermal vacuum chamber in Tsukuba Space Center

    Suganuma, Masahiro; Katayama, Haruyoshi; Naitoh, Masataka; Imai, Tadashi; Miyamoto, Masashi; Maruyama, Kenta; Kaneda, Hidehiro; Tange, Yoshio; Nakagawa, Takao

    2010-07-01

    We present a test of optical metrology for 800-mm spaceborne optics in the 6-m radiometer thermal vacuum chamber at JAXA's Tsukuba Space Center of JAXA. Under the framework of the JAXA's large-optics study program for astronomy and Earth observations, we developed a test bench for interferometric metrology of large optics with an auto-collimation method in the chamber. The optical system was aligned in a horizontal light-axis configuration within the facility limit to handle a 3.5-m aperture telescope like SPICA. A high-speed interferometer was contained in an aluminum and titanmade pressure vessel, which was mounted on the five-axis stage. We tested the 800-mm lightweight C/SiC optics using a 900-mm diameter flat mirror. Alignment changes in tilts of about ten arcseconds were observed as pressure went down from 1 atm to vacuum. After we re-aligned the interferometer and flat mirror, the wavefronts through the optics under vacuum were observed to increase in astigmatism aberration by 0.07λRMS at λ=633nm from under atmosphere, which might be caused by a deformation in the test optics or flat mirror.

  18. Safety analysis report for packaging: the ORNL DOT specification 6M - special form package

    The ORNL DOT Specification 6M - Special Form Package was fabricated at the Oak Ridge Nation al Laboratory (ORNL) for the transport of Type B solid non-fissile radioactive materials in special form. The package was evaluated on the basis of tests performed by the Dow Chemical Company, Rocky Flats Division, on the DOT-6M container and special form tests performed on a variety of stainless steel capsules at ORNL by Operations Division personnel. The results of these evaluations demonstrate that the package is in compliance with the applicable regulations for the transport of Type B quantities in special form of non-fissile radioactive materials

  19. A Signature of Self-Organized Criticality in the HT-6M Edge Plasma Turbulence

    WANG Wen-Hao; YU Chang-Xuan; WEN Yi-Zhi; XU Yu-Hong; LING Bi-Li; GONG Xian-Zu; LIU Bao-Hua; WAN Bao-Nian

    2001-01-01

    ower spectra of electron density and floating potential fluctuations in the velocity shear layer of the HT-6M edge region have been measured and analysed. All the spectra have three distinct frequency regions with the spectral decay indices typical of self-organized criticality systems (0, -1 and -4) when Doppler shift effects induced by the plasma E × B flow velocity have been taken into account. These results are consistent with the predictions of the self-organized criticality models, which may be an indication of edge plasma turbulence in the HT-6M tokamak evolving into a critical state independent of local plasma parameters.

  20. Chemical Bond Parameters in Sr3MRhO6 (M=Rare earth)

    2000-01-01

    Chemical bond parameters, that is, bond covalency, bond valence, macroscopic linear susceptibility, and oxidation states of elements in Sr3MRhO6 (M=Sm, Eu, Tb, Dy, Ho, Er, Yb) have been calculated. The results indicate that the bond covalency of M-O decreases sharply with the decrease of ionic radius of M3+ from Sm to Yb, while no obvious trend has been found for Rh-O and Sr-O bonds. The global instability index indicates that the crystal structures of Sr3MrhO6 (M = Sm, Eu, Tb, Dy, Ho) have strained bonds.

  1. Safety analysis report for packaging: the ORNL DOT specification 6M - tritium trap package

    The ORNL DOT Specification 6M--Tritium Trap Package was fabricated at the Oak Ridge National Laboratory (ORNL) for the transport of Type B quantities of tritium as solid uranium tritide. The package was evaluated on the basis of tests performed by the Dow Chemical Company, Rocky Flats Division, on the DOT-6M container, a drop test performed by the ORNL Operations Division, and International Atomic Energy Agency (IAEA) approvals on a similar tritium transport container. The results of these evaluations demonstrate that the package is in compliance with the applicable regulations for the transport of Type B quantities of tritium. 4 references, 8 figures

  2. OVERVIEW OF THE ATACAMA COSMOLOGY TELESCOPE: RECEIVER, INSTRUMENTATION, AND TELESCOPE SYSTEMS

    The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the cosmic microwave background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco in the Atacama Desert, at an altitude of 5190 m. A 6 m off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three 1000-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space millimeter-wave optics. Each frequency band has a field of view of approximately 22' x 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

  3. The Robotic Super-LOTIS Telescope: Results & Future Plans

    Williams, G G; Park, H S; Barthelmy, S D; Hartmann, D H; Updike, A; Hurley, K

    2008-01-01

    We provide an overview of the robotic Super-LOTIS (Livermore Optical Transient Imaging System) telescope and present results from gamma-ray burst (GRB) afterglow observations using Super-LOTIS and other Steward Observatory telescopes. The 0.6-m Super-LOTIS telescope is a fully robotic system dedicated to the measurement of prompt and early time optical emission from GRBs. The system began routine operations from its Steward Observatory site atop Kitt Peak in April 2000 and currently operates every clear night. The telescope is instrumented with an optical CCD camera and a four position filter wheel. It is capable of observing Swift Burst Alert Telescope (BAT) error boxes as early or earlier than the Swift UV/Optical Telescope (UVOT). Super-LOTIS complements the UVOT observations by providing early R- and I-band imaging. We also use the suite of Steward Observatory telescopes including the 1.6-m Kuiper, the 2.3-m Bok, the 6.5-m MMT, and the 8.4-m Large Binocular Telescope to perform follow-up optical and near ...

  4. Measuring Atmospheric Neutrino Oscillations with Neutrino Telescopes

    Albuquerque, Ivone F. M.; Smoot, George F.

    2001-01-01

    Neutrino telescopes with large detection volumes can demonstrate that the current indications of neutrino oscillation are correct or if a better description can be achieved with non-standard alternatives. Observations of contained muons produced by atmospheric neutrinos can better constrain the allowed region for oscillations or determine the relevant parameters of non-standard models. We analyze the possibility of neutrino telescopes measuring atmospheric neutrino oscillations. We suggest ad...

  5. Complete $\\alpha^6\\,m$ corrections to the ground state of H$_2$

    Puchalski, Mariusz; Czachorowski, Pawel; Pachucki, Krzysztof

    2016-01-01

    We perform the calculation of all relativistic and quantum electrodynamic corrections of the order of $\\alpha^6\\,m$ to the ground electronic state of a hydrogen molecule and present improved results for the dissociation and the fundamental transitions energies. These results open the window for the high-precision spectroscopy of H$_2$ and related low-energy tests of fundamental interactions.

  6. Taiwan Automated Telescope Network

    Shuhrat Ehgamberdiev; Alexander Serebryanskiy; Antonio Jimenez; Li-Han Wang; Ming-Tsung Sun; Javier Fernandez Fernandez; Dean-Yi Chou

    2010-01-01

    A global network of small automated telescopes, the Taiwan Automated Telescope (TAT) network, dedicated to photometric measurements of stellar pulsations, is under construction. Two telescopes have been installed in Teide Observatory, Tenerife, Spain and Maidanak Observatory, Uzbekistan. The third telescope will be installed at Mauna Loa Observatory, Hawaii, USA. Each system uses a 9-cm Maksutov-type telescope. The effective focal length is 225 cm, corresponding to an f-ratio of 25. The field...

  7. The Taiwanese-American Occultation Survey: The Multi-Telescope Robotic Observatory

    Lehner, M J; Wang, J -H; Marshall, S L; Schwamb, M E; Zhang, Z -W; Bianco, F B; Giammarco, J; Porrata, R; Alcock, C; Axelrod, T; Byun, Y -I; Chen, W P; Cook, K H; Davé, R; King, S -K; Lee, T; Lin, H -C; Wang, S -Y

    2008-01-01

    The Taiwanese-American Occultation Survey (TAOS) operates four telescopes to search for occultations of stars by Kuiper Belt Objects. This paper provides a detailed description of the TAOS multi-telescope system.

  8. Effects of high Z probe on plasma behavior in HT-6M tokamak

    Molybdenum and tungsten probes have been tested in HT-6M tokamak under various discharge conditions aiming to find out the conditions in which high Z PFC can be used without serious degradation of core plasma performance. In normal OH discharges, the degradation of core plasma performance was found only when the probe was inserted beyond 3.0 cm inside the last closed flux surface (LCFS). The plasma performance did not change with positive biasing to the probe, whereas central Te degraded during negative biasing of -100 V. The insertion of the Mo probe to 1.5 cm inside the LCFS made a change in the threshold power of the L-H transition in EOH discharges. These results suggest a certain operation range of the H-mode in the EOH discharge with the Mo probe in HT-6M. (author)

  9. Effects of high Z probe on plasma behavior in HT-6M tokamak

    Molybdenum and tungsten probes have been tested in HT-6M tokamak under various discharge conditions aiming to find out the conditions in which high Z PFC can be used without serious degradation of core plasma performance. In normal OH discharges, the degradation of core plasma performance was found only when the probe was inserted beyond 3.0 cm inside the last closed flux surface (LCFS). The plasma performance did not change with positive biasing to the probe, whereas central Te degraded during negative biasing of -100 V. The insertion of the Mo probe to 1.5 cm inside the LCFS made a change in the threshold power of the L-H transition in EOH discharges. These results suggest a certain operation range of the H-mode in the EOH discharge with the Mo probe in HT-6M. (orig.)

  10. Effects of high Z probe on plasma behavior in HT-6M tokamak

    Li, J.; Gong, X.; Luo, L.; Yin, F. X.; Noda, N.; Wan, B.; Xu, W.; Gao, X.; Yin, F.; Jiang, J. G.; Wu, Z.; Zhao, J. Y.; Wu, M.; Liu, S.; Han, Y.

    1997-02-01

    Molybdenum and tungsten probes have been tested in HT-6M tokamak under various discharge conditions aiming to find out the conditions in which high Z PFC can be used without serious degradation of core plasma performance. In normal OH discharges, the degradation of core plasma performance was found only when the probe was inserted beyond 3.0 cm inside the last closed flux surface (LCFS). The plasma performance did not change with positive biasing to the probe, whereas central Te degraded during negative biasing of -100 V. The insertion of the Mo probe to 1.5 cm inside the LCFS made a change in the threshold power of the L-H transition in EOH discharges. These results suggest a certain operation range of the H-mode in the EOH discharge with the Mo probe in HT-6M.

  11. 'n Evaluering van die 6M-Simulasie opleidingkursus vir oningewyde swart werkers

    R. van Niekerk

    1984-11-01

    Full Text Available Evaluation of the 6M Simulation Training Course is discussed with reference to mastery of course content, influence of training on job performance and reaction of course attendants to the course. Results indicate a significant increase in knowledge, irrespective of variables such as age, educational qualifications, years of service, home language, place of origin and job category. A positive change in 34 items related to the job situation and a positive reaction to the course content and training techniques were also found. .Opsomming'n Evaluering van die 6M-Simulasie Opleidingskursus word bespreek met verwysing na die bemeestering van kursusinhoud, die invloed van opleiding op werkprestasie en reaksie van kursusgangers. Resultate dui op 'n beduidende toename in kennis ongeag tussenkomende veranderlikes soos ouderdom, opvoedkundige kwalifikasies, jare diens, huistaal, geboorteplek en werkkategorie. 'n Positiewe reaksie op 34 vrae wat verband hou met die werksituasie, en op die kursusinhoud en opleidingstegnieke word ook gerapporteer.

  12. Syntheses, structures, and optical properties of Ba4MInSe6 (M=Cu, Ag)

    Two new quaternary chalcogenides, namely Ba4MInSe6 (M=Cu, Ag), were synthesized by solid state reactions. These two isostructural compounds adopt the Ba2MnS3 structure type in the orthorhombic space group Pnma. In the structure, the M and In atoms randomly occupy one crystallographic unique metal position with the molar ratio of 1:1 The (M/In)Se4 tetrahedra are connected to each other by corner-sharing to form one-dimensional chains along the b direction, which are separated by mono-capped trigonal prismatically coordinated Ba atoms. Based on the diffuse reflectance spectrum, the optical band gaps were determined to be 2.23(2) and 2.41(2) eV for Ba4CuInSe6 and Ba4AgInSe6, respectively. - Graphical abstract: In the structure of Ba4MInSe6 (M=Cu, Ag), the (M/In)Se4 tetrahedra are connected by corner-sharing to form chains along the b direction, which are separated by Ba atoms. Highlights: ► Two new quaternary chalcogenides, Ba4MInSe6 (M=Cu, Ag), were synthesized. ► Ba4MInSe6 (M=Cu, Ag) are isostructural and crystallize in the Ba2MnS3 structure type ► The (M/In)Se4 tetrahedra are connected by corner-sharing to form chains along the b direction. ► The chains are separated by mono-capped trigonal prismatically coordinated Ba atoms. ► The optical band gaps are 2.23(2) and 2.41(2) eV for Ba4CuInSe6 and Ba4AgInSe6, respectively.

  13. The Dutch Open Telescope

    Rutten, R. J.; Hammerschlag, R.H.; Bettonvil, F.C.M.

    2001-01-01

    The Dutch Open Telescope is a new and novel optical solar telescope on La Palma. It aims at high resolution by combining an excel- lent site on La Palma with an open tower and an open telescope and leads the way to large-aperture high resolution telescopes. We brie y review the DOT principle, structure and goals. More information is found at the DOT website.

  14. The SOFIA Telescope

    Krabbe, Alfred

    2000-01-01

    The SOFIA telescope as the heart of the observatory is a major technological challenge. I present an overview on the astro-nomical and scientific requirements for such a big airborne observatory and demonstrate the impact of these requirements on the layout of SOFIA, in particular on the telescope design as it is now. Selected components of the telescope will be de-scribed in their context and functionality. The current status of the telescope is presented.

  15. The Green Bank Telescope

    Prestage, R. M.; Constantikes, K. T.; Hunter, T. R.; King, L. J.; Lacasse, R. J.; Lockman, F. J.; Norrod, R. D.

    2009-08-01

    The Robert C. Byrd Green Bank Telescope of the National Radio Astronomy Observatory is the world's premiere single-dish radio telescope operating at centimeter to long millimeter wavelengths. This paper describes the history, construction, and main technical features of the telescope.

  16. Auto Adjusting Astronomical Telescope

    Rohit R. Ghalsasi; Prof. N. D. Dhoot

    2014-01-01

    Astronomical telescope is powerful and basic tool for star or celestial observation. Here we proposed integrated system using Raspberry Pi for auto adjusting astronomical telescope. This integrated circuit helps to control stellar monitoring, stellar targeting, and tracking functions of telescope. Astro compass gives the direction of the celestial objects.

  17. The MAGIC Telescope

    Bigongiari, Ciro

    2005-01-01

    MAGIC (Major Atmospheric Gamma Imaging Cherenkov telescope) is presently the largest ground-based gamma ray telescope. MAGIC has been taking data regularly since October 2004 at the Roque de los Muchachos Observatory on the island of La Palma. In this paper the MAGIC telescope status, its performances and some preliminary results on observed gamma ray sources are presented.

  18. Auto Adjusting Astronomical Telescope

    Rohit R. Ghalsasi

    2014-04-01

    Full Text Available Astronomical telescope is powerful and basic tool for star or celestial observation. Here we proposed integrated system using Raspberry Pi for auto adjusting astronomical telescope. This integrated circuit helps to control stellar monitoring, stellar targeting, and tracking functions of telescope. Astro compass gives the direction of the celestial objects.

  19. ATST telescope mount: telescope of machine tool

    Jeffers, Paul; Stolz, Günter; Bonomi, Giovanni; Dreyer, Oliver; Kärcher, Hans

    2012-09-01

    The Advanced Technology Solar Telescope (ATST) will be the largest solar telescope in the world, and will be able to provide the sharpest views ever taken of the solar surface. The telescope has a 4m aperture primary mirror, however due to the off axis nature of the optical layout, the telescope mount has proportions similar to an 8 meter class telescope. The technology normally used in this class of telescope is well understood in the telescope community and has been successfully implemented in numerous projects. The world of large machine tools has developed in a separate realm with similar levels of performance requirement but different boundary conditions. In addition the competitive nature of private industry has encouraged development and usage of more cost effective solutions both in initial capital cost and thru-life operating cost. Telescope mounts move relatively slowly with requirements for high stability under external environmental influences such as wind buffeting. Large machine tools operate under high speed requirements coupled with high application of force through the machine but with little or no external environmental influences. The benefits of these parallel development paths and the ATST system requirements are being combined in the ATST Telescope Mount Assembly (TMA). The process of balancing the system requirements with new technologies is based on the experience of the ATST project team, Ingersoll Machine Tools who are the main contractor for the TMA and MT Mechatronics who are their design subcontractors. This paper highlights a number of these proven technologies from the commercially driven machine tool world that are being introduced to the TMA design. Also the challenges of integrating and ensuring that the differences in application requirements are accounted for in the design are discussed.

  20. Ultra high tip speed (670.6 m/sec) fan stage with composite rotor: Aerodynamic and mechanical design

    Halle, J. E.; Burger, G. D.; Dundas, R. E.

    1977-01-01

    A highly loaded, single-stage compressor having a tip speed of 670.6 m/sec was designed for the purpose of investigating very high tip speeds and high aerodynamic loadings to obtain high stage pressure ratios at acceptable levels of efficiency. The design pressure ratio is 2.8 at an adiabatic efficiency of 84.4%. Corrected design flow is 83.4 kg/sec; corrected design speed is 15,200 rpm; and rotor inlet tip diameter is 0.853 m. The rotor uses multiple-circular-arc airfoils from 0 to 15% span, precompression airfoils assuming single, strong oblique shocks from 21 to 43% span, and precompression airfoils assuming multiple oblique shocks from 52% span to the tip. Because of the high tip speeds, the rotor blades are designed to be fabricated of composite materials. Two composite materials were investigated: Courtaulds HTS graphite fiber in a Kerimid 601 polyimide matrix and the same fibers in a PMR polyimide matrix. In addition to providing a description of the aerodynamic and mechanical design of the 670.0 m/sec fan, discussion is presented of the results of structural tests of blades fabricated with both types of matrices.

  1. Hα line shape in front of the limiter in HT-6M tokamak

    In this paper Hα line shape in front of the limiter in HT-6M tokamak is analyzed by multi-Gaussian fitting. The energy distribution of neutral hydrogen atoms reveals that Hα radiation is contributed by Frank-Condon (FC) atoms, atoms reflected at the limiter surface and charge exchange. Dissociation of hydrogen molecules and reflection of particles at the limiter surface are dominant in edge recycling. To lower particle reflection at the limiter surface is an important issue for controlling edge recycling. The measured profiles of neutral hydrogen atom density are reproduced by particle continue equation and a simplified one-dimension Monte-Carlo simulation code. (author)

  2. Cosmic ray tests of a 4.6 m-long test drift chamber for JLC

    Kurihara, Y; Sudo, S; Abe, T; Fujii, K; Ishihara, N; Khalatyan, N; Matsui, T; Nitoh, O; Ohama, T; Okuno, H; Sugiyama, A; Takahashi, K; Watanabe, T; Yoshida, T

    2000-01-01

    Performance of a 4.6 m-long drift chamber filled with a CO sub 2 iso-butane (90:10) mixture was studied using cosmic-ray data, in the course of detector R and D for JLC. After correcting the data for wire displacements due to gravitational and electrostatic forces, a spatial resolution of 100 mu m per wire was achieved over the full length of the chamber. The relation between wire efficiency and oxygen remnant in the chamber gas is also discussed.

  3. Cosmic ray tests of a 4.6 m-long test drift chamber for JLC

    Performance of a 4.6 m-long drift chamber filled with a CO2 iso-butane (90:10) mixture was studied using cosmic-ray data, in the course of detector R and D for JLC. After correcting the data for wire displacements due to gravitational and electrostatic forces, a spatial resolution of 100 μm per wire was achieved over the full length of the chamber. The relation between wire efficiency and oxygen remnant in the chamber gas is also discussed

  4. Zn/gelled 6 M KOH/O 2 zinc-air battery

    Mohamad, A. A.

    The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6 M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50 mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell.

  5. Satellite description

    Gillett, F. C.; Clegg, P. E.; Neugebauer, G.; Langford, D.; Pouw, A.; Irace, W.; Houck, J.

    The onboard computers and their associated software, the attitude control system, and data recording and the communication links of the infrared astronomy satellite (TRAS) are discussed. The IRAS telescope system is considered in detail. Attention is directed towards the cryogenics, thermal control, optics, focal plane assembly, and electronics associated with the telescope system.

  6. New ferromagnetic semiconductor double perovskites: La2FeMO6 (M = Co, Rh, and Ir)

    Highlights: • The La2FeCoO6 is a potential candidate for ferromagnetic semiconductor. • The FM semiconductor originates from the exchange effect between Fe and Co. • We calculate the 406 combinations of possible La2MM′O6 compounds here. - Abstract: Density functional theory with generalized gradient approximation (GGA) plus onsite Coulomb interaction (GGA + U) was used to calculate physical proprieties of new ferromagnetic semiconductor materials of the La2FeMO6 (M = Co, Rh, and Ir). We calculate the 406 (C229) La2MM′O6 compounds which MM′ can be any pair taken from the 29 transition metal elements except La. La2FeCoO6 is a potential candidate for ferromagnetic semiconductor. For the GGA + U scheme, La2FeCo6 remains a stable FM semiconductor, whereas La2FeRhO6 and La2FeIrO6 are shown the FM and AFM states of which are degenerate with each other. The FM semiconductor gap remains in existence under tensile or compressive strain in La2FeRhO6 and La2FeIrO6. The superexchange interaction in ferromagnetic La2FeMO6 (M = Co, Rh, and Ir) is high spin (HS) Fe completely empty eg orbital hopping to the half-filled (LS) Co (Rh and Ir) empty eg orbital

  7. Alignment techniques for calibration and installation of a 6-m Toroidal Grating Monochromator

    Wallace, Daniel J.; Hansen, Roger W. C.; Perkins, F. Keith; Pruett, Charles H.; Welnak, John

    1990-05-01

    The University of Wisconsin Synchrotron Radiation Center Optics Group has recently completed the installation of three 6-m Toroidal Grating Monochromator (TGM) beamlines on the Aladdin ring. Two of these beamlines image bending-magnet radiation and the third images radiation from the 30-period undulator on loan to the Synchrotron Radiation Center from the Stanford Synchrotron Radiation Laboratory and Lawrence Berkeley Laboratory. Each beamline required an accurate alignment strategy. This is due to the long source-to-final-image distance and the five independent critical elements: entrance mirror, entrance slit, grating chamber, exit slit, and exit mirror. The TGM grating chamber houses up to six gratings on a revolving carousel which is scanned with a sine-drive. We will describe grating stability checks and adjustments to linearize the grating scan calibration. We will also outline the basic alignment procedures from the source point, through the grating chamber, to the final focus. The procedure we have used provided sufficiently accurate alignment to realize the high throughput and resolution capabilities of the 6-m TGMs. The methods also allow later checks on critical degrees of freedom of the optical components.

  8. Alignment techniques for calibration and installation of a 6-m toroidal grating monochromator

    The University of Wisconsin Synchrotron Radiation Center Optics Group has recently completed the installation of three 6-m Toroidal Grating Monochromator (TGM) beamlines on the Aladdin ring. Two of these beamlines image bending-magnet radiation and the third images radiation from the 30-period undulator on loan to the Synchrotron Radiation Center from the Standford Synchrotron Radiation Laboratory and Lawrence Berkeley Laboratory. Each beamline required an accurate alignment strategy. This is due to the long source-to-final-image distance and the five independent critical elements: entrance mirror, entrance slit, grating chamber, exit slit, and exit mirror. The TGM grating chamber houses up to six gratings on a revolving carousel which is scanned with a sine-drive. We will describe grating stability checks and adjustments to linearize the grating scan calibration. We will also outline the basic alignment procedures from the source point, through the grating chamber, to the final focus. The procedure we have used provided sufficiently accurate alignment to realize the high throughput and resolution capabilities of the 6-m TGMs. The methods also allow later checks on critical degrees of freedom of the optical components. (orig.)

  9. JWST Pathfinder Telescope Integration

    Matthews, Gary W.; Kennard, Scott H.; Broccolo, Ronald T.; Ellis, James M.; Daly, Elizabeth A.; Hahn, Walter G.; Amon, John N.; Mt. Pleasant, Stephen M.; Texter, Scott; Atkinson, Charles B.; McKay, Andrew; Levi, Joshua; Keski-Kuha, Ritva; Feinberg, Lee

    2015-01-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. In 2014, a major risk reduction effort related to the Alignment, Integration, and Test (AI&T) of the segmented telescope was completed. The Pathfinder telescope includes two Primary Mirror Segment Assemblies (PMSA's) and the Secondary Mirror Assembly (SMA) onto a flight-like composite telescope backplane. This pathfinder allowed the JWST team to assess the alignment process and to better understand the various error sources that need to be accommodated in the flight build. The successful completion of the Pathfinder Telescope provides a final integration roadmap for the flight operations that will start in August 2015.

  10. Automated telescope scheduling

    Johnston, Mark D.

    1988-08-01

    With the ever increasing level of automation of astronomical telescopes the benefits and feasibility of automated planning and scheduling are becoming more apparent. Improved efficiency and increased overall telescope utilization are the most obvious goals. Automated scheduling at some level has been done for several satellite observatories, but the requirements on these systems were much less stringent than on modern ground or satellite observatories. The scheduling problem is particularly acute for Hubble Space Telescope: virtually all observations must be planned in excruciating detail weeks to months in advance. Space Telescope Science Institute has recently made significant progress on the scheduling problem by exploiting state-of-the-art artificial intelligence software technology. What is especially interesting is that this effort has already yielded software that is well suited to scheduling groundbased telescopes, including the problem of optimizing the coordinated scheduling of more than one telescope.

  11. JWST pathfinder telescope integration

    Matthews, Gary W.; Kennard, Scott H.; Broccolo, Ronald T.; Ellis, James M.; Daly, Elizabeth A.; Hahn, Walter G.; Amon, John N.; Mt. Pleasant, Stephen M.; Texter, Scott; Atkinson, Charles B.; McKay, Andrew; Levi, Joshua; Keski-Kuha, Ritva; Feinberg, Lee

    2015-08-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. In 2014, a major risk reduction effort related to the Alignment, Integration, and Test (AI and T) of the segmented telescope was completed. The Pathfinder telescope includes two Primary Mirror Segment Assemblies (PMSA's) and the Secondary Mirror Assembly (SMA) onto a flight-like composite telescope backplane. This pathfinder allowed the JWST team to assess the alignment process and to better understand the various error sources that need to be accommodated in the flight build. The successful completion of the Pathfinder Telescope provides a final integration roadmap for the flight operations that will start in August 2015.

  12. Construction and Test of 3.6 m Nb3Sn Racetrack Coils for LARP

    Wanderer, P.; Ambrosio, G.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Cheng, D. W.; Cozzolino, J.; Dietderich, D.R.; Escallier, J.; Feher, S.; Ferracin, P.; Ganetis, G.; Ghosh, A. K.; Gupta, R. C.; Hafalia,, A. R.; Hannaford, C. R.; Joshi, P.; Kovach, P.; Lietzke, A. F.; Lizarazo, J.; Louie, W.; Marone, A.; McInturff, A.D.; Muratore, J.; Nobrega, F.; Sabbi, G.; Schmalzle, J.; Thomas, R.; Turrioni, D.

    2008-06-01

    Development of high-performance Nb{sub 3}Sn quadrupoles is one of the major goals of the LHC Accelerator Research Program (LARP). As part of this program, long racetrack magnets were made in order to check the fabrication steps for long Nb{sub 3}Sn coils, that the changes in coil length that take place during reaction and cooldown are correctly accounted for in the quadrupole design, and the use of a long aluminum shell for the support structure. This paper reports the construction of the first long Nb{sub 3}Sn magnet with racetrack coils 3.6 m long. The magnet reached a nominal 'plateau' at 9596 A after five quenches. This is about 90% of the estimated conductor limit. The peak field in the coils at this current was 11 T.

  13. Density fluctuation in HT-6M tokamak by CO2 laser scattering

    The small scale density fluctuations in the interior of HT-6M Ohmic plasma have been studied by CO2 laser collective scattering system in deuterium discharges covering a wide range of bar nqa (chord-average density times safety factor at the limiter) and energy confinement time. The relative density fluctuation level in the interior is inversely proportional to the toroidal magnetic field and average density, and the energy confinement time τE decreases with the fluctuation level increasing in the region where τE linearly increases with bar nq0.5a and satisfies the Goldston scaling law. It is suggested that the microturbulence in the interior zone is responsible for anomalous transport in tokamaks

  14. Drop Simulation of 6M Drum with Locking-Ring Closure and Liquid Contents

    This paper presents the dynamic simulation of the 6M drum with a locking-ring type closure subjected to a 4.9-foot drop. The drum is filled with water to 98 percent of overflow capacity. A three dimensional finite-element model consisting of metallic, liquid and rubber gasket components is used in the simulation. The water is represented by a hydrodynamic material model in which the material's volume strength is determined by an equation of state. The explicit numerical method based on the theory of wave propagation is used to determine the combined structural response to the torque load for tightening the locking-ring closure and to the impact load due to the drop

  15. ICRF experiments and synergy with LHCD on HT-6M tokamak

    The successful ion cyclotron heating (ICRH) experiment with high power density of nearly 1MW/m3 was carried out in HT-6M tokamak. The good heating efficiency was achieved by using different wall conditioning techniques, such as He GDC, Ti gettering and boronization. With 300kW injected RF power, the ion temperature reach about 750eV and Te increases from 700eV to about 1keV. Synergy effects between lower hybrid current drive (LHCD) and ICRH have some unique features. The current driven efficiency improved in full current drive case from 0.8x1019AW-1M-2 (without ICRH) to 1.75x1019AW-1M-2 (with ICRH). The reason for this high current driven efficiency may because the mode conversion at ion-ion hybrid resonance to an Ion Bernstein Wave (IBW) which is damped on the fast electron. (author)

  16. Zn/gelled 6M KOH/O{sub 2} zinc-air battery

    Mohamad, A.A. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)

    2006-09-13

    The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell. (author)

  17. The great Melbourne telescope

    Gillespie, Richard

    2011-01-01

    Erected at Melbourne Observatory in 1869, the telescope was the second largest in the world, designed to explore the nature of the nebulae in the southern skies. Richard Gillespie, head of the History and Technology department at the Melbourne museum has written an entertaining account of the telescope's extraordinary history and tells the story through an amazing cast of characters whose lives intersected with the telescope.

  18. Gravitational lensing studies with the 4-m International Liquid Mirror Telescope (ILMT)

    Jean, C; Claeskens, Jean-François; Surdej, Jean

    1999-01-01

    A 4-m International Liquid Mirror Telescope (ILMT) is being built in the north of Chile by an international consortium and will become operational in two years from now. We present here a short description of the telescope as well as estimates of the microlensing, macrolensing and weak lensing effects expected from a deep, multicolor imaging survey made with such a telescope.

  19. Active optics system of the VLT Survey Telescope.

    Schipani, Pietro; Noethe, Lothar; Magrin, Demetrio; Kuijken, Konrad; Arcidiacono, Carmelo; Argomedo, Javier; Capaccioli, Massimo; Dall'Ora, Massimo; D'Orsi, Sergio; Farinato, Jacopo; Fierro, Davide; Holzlöhner, Ronald; Marty, Laurent; Molfese, Cesare; Perrotta, Francesco; Ragazzoni, Roberto; Savarese, Salvatore; Rakich, Andrew; Umbriaco, Gabriele

    2016-03-01

    This paper describes the active optics system of the VLT Survey Telescope, the 2.6-m survey telescope designed for visible wavelengths of the European Southern Observatory at Cerro Paranal, in the Atacama desert. The telescope is characterized by a wide field of view (1.42 deg diameter), leading to tighter active optics than in conventional telescopes, in particular for the alignment requirements. We discuss the effects of typical error sources on the image quality and present the specific solutions adopted for wavefront sensing and correction of the aberrations, which are based on the shaping of a monolithic primary mirror and the positioning of the secondary in five degrees of freedom. PMID:26974616

  20. Measuring atmospheric neutrino oscillations with neutrino telescopes

    Neutrino telescopes with large detection volumes can demonstrate whether the current indications of neutrino oscillation are correct or if a better description can be achieved with nonstandard alternatives. Observations of contained muons produced by atmospheric neutrinos can better constrain the allowed region for oscillations or determine the relevant parameters of nonstandard models. We analyze the possibility of neutrino telescopes measuring atmospheric neutrino oscillations. We suggest adjustments to improve this potential. An addition of four densely instrumented strings to the AMANDA II detector makes oscillation observations feasible. Such a configuration is competitive with current and proposed experiments

  1. Measuring Atmospheric Neutrino Oscillations with Neutrino Telescopes

    Albuquerque, I F M; Albuquerque, Ivone F.M.; Smoot, George F.

    2001-01-01

    Neutrino telescopes with large detection volumes can demonstrate that the current indications of neutrino oscillation are correct or if a better description can be achieved with non-standard alternatives. Observations of contained muons produced by atmospheric neutrinos can better constrain the allowed region for oscillations or determine the relevant parameters of non-standard models. We analyze the possibility of neutrino telescopes measuring atmospheric neutrino oscillations. We suggest adjustments to improve this potential. An addition of four densely-instrumented strings to the AMANDA II detector makes observations feasible. Such a configuration is competitive with current and proposed experiments.

  2. Measuring atmospheric neutrino oscillations with neutrino telescopes

    Albuquerque, Ivone F. M.; Smoot, George F.

    2001-09-01

    Neutrino telescopes with large detection volumes can demonstrate whether the current indications of neutrino oscillation are correct or if a better description can be achieved with nonstandard alternatives. Observations of contained muons produced by atmospheric neutrinos can better constrain the allowed region for oscillations or determine the relevant parameters of nonstandard models. We analyze the possibility of neutrino telescopes measuring atmospheric neutrino oscillations. We suggest adjustments to improve this potential. An addition of four densely instrumented strings to the AMANDA II detector makes oscillation observations feasible. Such a configuration is competitive with current and proposed experiments.

  3. Wind responses of Giant Magellan telescope

    Irarrazaval, Benjamin; Buleri, Christine; Johns, Matt

    2014-08-01

    The Giant Magellan Telescope (GMT) is 25 meter diameter extremely large ground based infrared/optical telescope being built by an international consortium of universities and research institutions. It will be located at the Las Campanas Observatory in Chile. The GMT primary mirror consists of seven 8.4 meter diameter borosilicate mirror segments. Two seven segment Gregorian secondary mirror systems will be built; an Adaptive Secondary Mirror (ASM) to support adaptive optics modes and a Fast-steering Secondary Mirror (FSM) with monolithic segments to support natural seeing modes when the ASM is being serviced. Wind excitation results in static deformation and vibration in the telescope structure that affects alignment and image jitter performance. The telescope mount will reject static and lower frequency windshake, while each of the Faststeering Secondary Mirror (FSM) segments will be used to compensate for the higher frequency wind-shake, up to 20 Hz. Using a finite element model of the GMT, along with CFD modeling of the wind loading on the telescope structure, wind excitation scenarios were created to study the performance of the FSM and telescope against wind-induced jitter. A description of the models, methodology and results of the analyses are presented.

  4. Environmental description

    Lahtinen, Riitta; Palmer, Russ

    2012-01-01

    Environmental description is the description of general, physical, personal and social space and action, where visual, auditory and other sensory information is shared with the receiver in spoken, written or sign language, either vocally, i.e. producing sounds or in another form (pointing, touching, drawing). It can be divided into the expression of basic characteristics, basic description, precise and extended description, and it can be carried out physically on the spot (clos...

  5. High resolution telescope

    Massie, Norbert A.; Oster, Yale

    1992-01-01

    A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employs speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by an electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activites. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

  6. Athermal laser launch telescopes

    Kamphues, F.G.; Henselmans, R.; Rijnveld, N.; Lemmen, M.H.J.; Doelman, N.J.; Nijkerk, M.D.

    2011-01-01

    ESO has developed a concept for a compact laser guide star unit for use in future Adaptive Optics (AO) systems. A small powerful laser is combined with a telescope that launches the beam, creating a single modular unit that can be mounted directly on a large telescope. This approach solves several o

  7. Implementation and Evaluation of Technology Mentoring Program Developed for Teacher Educators: A 6M-Framework

    Selim Gunuc

    2015-06-01

    Full Text Available The purpose of this basic research is to determine the problems experienced in the Technology Mentoring Program (TMP, and the study discusses how these problems affect the process in general. The implementation was carried out with teacher educators in the education faculty. 8 doctorate students (mentors provided technology mentoring implementation for one academic term to 9 teacher educators (mentees employed in the Education Faculty. The data were collected via the mentee and the mentor interview form, mentor reflections and organization meeting reflections. As a result, the problems based on the mentor, on the mentee and on the organization/institution were determined. In order to carry out TMP more effectively and successfully, a 6M-framework (Modifying, Meeting, Matching, Managing, Mentoring - Monitoring was suggested within the scope of this study. It could be stated that fewer problems will be encountered and that the process will be carried out more effectively and successfully when the structure in this framework is taken into consideration.

  8. Half sandwich structures of MCF6- (M = Ag and Au): An experimental and theoretical study

    Sun, Zhang; Tang, Zichao; Gao, Zhen

    2013-01-01

    The metal-hexafluorobenzene anionic complexes of [MC6F6]- (M = Ag and Au) were produced from the reactions between metal cluster generated by laser ablation and the hexafluorobenzene seeded in argon carrier gas, and were studied by photoelectron spectroscopy (PES) and density functional theory (DFT). The adiabatic electron affinities (EAs) of these corresponding complexes are measured from the experimental PE spectra at 193 nm photon energy. Also, the calculated EAs and the calculated density of states (DOS) spectra of these complexes in the ground state are conducted, which are in good agreement with their experimental PE spectra. The most possible structures of the anions [AgC6F6]- and [AuC6F6]- are the half-sandwich structures with C6v symmetry, in which the metal atom is above the center of the C6F6 plane. Furthermore, the molecular orbital (MO) analysis of these species indicates that the additional electron of the anions binds on the metal.

  9. Continuous synthesis process of hexagonal nanoplates of P6m ordered mesoporous silica.

    Jammaer, Jasper; van Erp, Titus S; Aerts, Alexander; Kirschhock, Christine E A; Martens, Johan A

    2011-08-31

    Hexagonally ordered mesoporous silica coined COK-12 was synthesized in a continuous process by combining streams of sodium silicate and citric acid/sodium citrate buffered solution of (ethylene oxide)(20)-(propylene oxide)(70)-(ethylene oxide)(20) triblock copolymer (Pluronic P123) from separate reservoirs. COK-12 precipitated spontaneously upon combining both streams at nearly neutral pH and ambient temperature. Stable intermediates of the COK-12 formation process could be prepared by limiting sodium silicate addition. Investigation of these intermediates using small-angle X-ray scattering revealed COK-12 formed via an assembly process departing from spherical uncharged core-shell P123-silica micelles. The sterical stabilization of these micelles decreased upon accumulation of silicate oligomers in their shell. Aggregation of the spherical micelles led to cylindrical micelles, which aligned and adopted the final hexagonal organization. This unprecedentedly fast formation of P6m ordered mesoporous silica was caused by two factors in the synthesis medium: the neutral pH favoring uncharged silicate oligomers and the high salt concentration promoting hydrophobic interactions with surfactant micelles leading to silica accumulation in the PEO shell. The easy continuous synthesis process is convenient for large-scale production. The platelet particle morphology with short and identical internal channels will be advantageous for many applications such as pore replication, nanotube or fiber growth, catalytic functionalization, drug delivery, film and sensor development, and in nano dyes as well as for investigation of pore diffusion phenomena. PMID:21790195

  10. Platform Deformation Refined Pointing and Phase Correction for the AMiBA Hexapod Telescope

    Koch, Patrick M.; Kesteven, Michael; Chang, Yu-Yen; Huang, Yau-De; Raffin, Philippe; Chen, Ke-Yung; Chereau, Guillaume; Chen, Ming-Tang; Ho, Paul T. P.; Huang, Chih-Wie; Ibanez-Romano, Fabiola; Jiang, Homin; Liao, Yu-Wei; Lin, Kai-Yang; Liu, Guo-Chin

    2009-01-01

    The Array for Microwave Background Anisotropy (AMiBA) is a radio interferometer for research in cosmology, currently operating 7 0.6m diameter antennas co-mounted on a 6m diameter platform driven by a hexapod mount. AMiBA is currently the largest hexapod telescope. We briefly summarize the hexapod operation with the current pointing error model. We then focus on the upcoming 13-element expansion with its potential difficulties and solutions. Photogrammetry measurements of the platform reveal ...

  11. A ribonucleoprotein complex protects the interleukin-6 mRNA from degradation by distinct herpesviral endonucleases.

    Mandy Muller

    2015-05-01

    Full Text Available During lytic Kaposi's sarcoma-associated herpesvirus (KSHV infection, the viral endonuclease SOX promotes widespread degradation of cytoplasmic messenger RNA (mRNA. However, select mRNAs escape SOX-induced cleavage and remain robustly expressed. Prominent among these is interleukin-6 (IL-6, a growth factor important for survival of KSHV infected B cells. IL-6 escape is notable because it contains a sequence within its 3' untranslated region (UTR that can confer protection when transferred to a SOX-targeted mRNA, and thus overrides the endonuclease targeting mechanism. Here, we pursued how this protective RNA element functions to maintain mRNA stability. Using affinity purification and mass spectrometry, we identified a set of proteins that associate specifically with the protective element. Although multiple proteins contributed to the escape mechanism, depletion of nucleolin (NCL most severely impacted protection. NCL was re-localized out of the nucleolus during lytic KSHV infection, and its presence in the cytoplasm was required for protection. After loading onto the IL-6 3' UTR, NCL differentially bound to the translation initiation factor eIF4H. Disrupting this interaction, or depleting eIF4H, reinstated SOX targeting of the RNA, suggesting that interactions between proteins bound to distant regions of the mRNA are important for escape. Finally, we found that the IL-6 3' UTR was also protected against mRNA degradation by the vhs endonuclease encoded by herpes simplex virus, despite the fact that its mechanism of mRNA targeting is distinct from SOX. These findings highlight how a multitude of RNA-protein interactions can impact endonuclease targeting, and identify new features underlying the regulation of the IL-6 mRNA.

  12. A ribonucleoprotein complex protects the interleukin-6 mRNA from degradation by distinct herpesviral endonucleases.

    Muller, Mandy; Hutin, Stephanie; Marigold, Oliver; Li, Kathy H; Burlingame, Al; Glaunsinger, Britt A

    2015-05-01

    During lytic Kaposi's sarcoma-associated herpesvirus (KSHV) infection, the viral endonuclease SOX promotes widespread degradation of cytoplasmic messenger RNA (mRNA). However, select mRNAs escape SOX-induced cleavage and remain robustly expressed. Prominent among these is interleukin-6 (IL-6), a growth factor important for survival of KSHV infected B cells. IL-6 escape is notable because it contains a sequence within its 3' untranslated region (UTR) that can confer protection when transferred to a SOX-targeted mRNA, and thus overrides the endonuclease targeting mechanism. Here, we pursued how this protective RNA element functions to maintain mRNA stability. Using affinity purification and mass spectrometry, we identified a set of proteins that associate specifically with the protective element. Although multiple proteins contributed to the escape mechanism, depletion of nucleolin (NCL) most severely impacted protection. NCL was re-localized out of the nucleolus during lytic KSHV infection, and its presence in the cytoplasm was required for protection. After loading onto the IL-6 3' UTR, NCL differentially bound to the translation initiation factor eIF4H. Disrupting this interaction, or depleting eIF4H, reinstated SOX targeting of the RNA, suggesting that interactions between proteins bound to distant regions of the mRNA are important for escape. Finally, we found that the IL-6 3' UTR was also protected against mRNA degradation by the vhs endonuclease encoded by herpes simplex virus, despite the fact that its mechanism of mRNA targeting is distinct from SOX. These findings highlight how a multitude of RNA-protein interactions can impact endonuclease targeting, and identify new features underlying the regulation of the IL-6 mRNA. PMID:25965334

  13. Hubble Space Telescope

    1990-02-01

    An overview of the mission of the Hubble Space Telescope, a joint project between NASA and the European Space Agency which will be used to study deep space, as well as our solar system is presented. The video contains animations depicting the Hubble Space Telescope in orbit, as well as footage of scientists at the Space Telescope Science Institute making real time observations. The images Hubble acquires will be downloaded into a database that contains images of over 19,000,0000 celestial objects called the Star Catalog.

  14. The Dutch Open Telescope

    Rutten, R. J.; Hammerschlag, R.H.; Bettonvil, F.C.M.

    2001-01-01

    The Utrecht Open Tower Telescope, recently renamed into \\Dutch Open Telescope", is now being installed at the Roque de los Muchachos Observatory on La Palma (Fig. 1). Like THEMIS, the DOT is a solar telescope of novel design, is located at a superior site, aims at high spatial resolution, is suited to polarimetry, has been long in the making, and should start its scientic career in 1997. Unlike THEMIS, the DOT has no dome, no vacuum enclosure, no post-focus equipment, and no long-term funding.

  15. The Dutch Open Telescope

    Rutten, R. J.; Hammerschlag, R.H.; Bettonvil, F.C.M.

    2001-01-01

    The Utrecht Open Tower Telescope, recently renamed into "Dutch Open Telescope", is now being installed at the Roque de los Muchachos Observatory on La Palma (Fig. 1). Like THEMIS, the DOT is a solar telescope of novel design, is located at a superior site, aims at high spatial resolution, is suited to polarimetry, has been long in the making, and should start its scientific career in 1997. Unlike THEMIS, the DOT has no dome, no vacuum enclosure, no post-focus equipment, and no long-term funding.

  16. The AMiBA Hexapod Telescope Mount

    Koch, Patrick M.; Kesteven, Michael; Nishioka, Hiroaki; Jiang, Homin; Lin, Kai-Yang; Umetsu, Keiichi; Huang, Yau-De; Raffin, Philippe; Chen, Ke-Jung; Ibanez-Romano, Fabiola; Chereau, Guillaume; Huang, Chih-Wei Locutus; Chen, Ming-Tang; Ho, Paul T. P.; Pausch, Konrad

    2009-01-01

    AMiBA is the largest hexapod astronomical telescope in current operation. We present a description of this novel hexapod mount with its main mechanical components -- the support cone, universal joints, jack screws, and platform -- and outline the control system with the pointing model and the operating modes that are supported. The AMiBA hexapod mount performance is verified based on optical pointing tests and platform photogrammetry measurements. The photogrammetry results show that the defo...

  17. Goddard Robotic Telescope (GRT)

    National Aeronautics and Space Administration — Since it is not possible to predict when a Gamma-Ray Burst (GRB) occurs, the follow-up ground telescopes must be distributed as uniform as possible all over the...

  18. The Dark Matter Telescope

    Tyson, J A; Angel, J R P; Wittman, David

    2001-01-01

    Weak gravitational lensing enables direct reconstruction of dark matter maps over cosmologically significant volumes. This research is currently telescope-limited. The Dark Matter Telescope (DMT) is a proposed 8.4 m telescope with a 3 degree field of view, with an etendue of 260 $(m. degree)^2$, ten times greater than any other current or planned telescope. With its large etendue and dedicated observational mode, the DMT fills a nearly unexplored region of parameter space and enables projects that would take decades on current facilities. The DMT will be able to reach 10-sigma limiting magnitudes of 27-28 magnitude in the wavelength range .3 - 1 um over a 7 square degree field in 3 nights of dark time. Here we review its unique weak lensing cosmology capabilities and the design that enables those capabilities.

  19. The Nordic Optical Telescope

    Djupvik, Anlaug Amanda; Andersen, Johannes

    2009-01-01

    An overview of the Nordic Optical Telescope (NOT) is presented. Emphasis is on current capabilities of direct interest to the scientific user community, including instruments. Educational services and prospects and strategies for the future are discussed briefly as well.

  20. Hubble Space Telescope

    The characteristics and capabilities of the Hubble Space Telescope (HST) are described. The telescope can provide an angular resolution of about 0.1 arcsec, a faint stellar limiting magnitude of about 28 mag, and UV observations greater than or equal to 1150 A. The scientific instruments on the HST include: a wide-field and planetary camera, a faint object spectrograph, a faint object camera, a high speed photometer, a high resolution spectrograph, and three fine guidance sensors. The role of the Space Telescope Science Institute in managing and distributing the HST data is examined. The application of the telescope to the study of cosmology, evolution, QSOs and AGNs, galaxies and cluster, stars and the interstellar medium, and planetary astronomy is proposed

  1. The Cherenkov Telescope Array

    Bigongiari, Ciro

    2016-01-01

    The Cherenkov Telescope Array (CTA) is planned to be the next generation ground based observatory for very high energy (VHE) gamma-ray astronomy. Gamma-rays provide a powerful insight into the non-thermal universe and hopefully a unique probe for new physics. Imaging Cherenkov telescopes have already discovered more than 170 VHE gamma-ray emitters providing plentiful of valuable data and clearly demonstrating the power of this technique. In spite of the impressive results there are indication...

  2. The Atacama Cosmology Telescope

    Kosowsky, Arthur

    2004-01-01

    The Atacama Cosmology Telescope (ACT) project is described. This multi-institution collaboration aims to produce arcminute-resolution and micro-Kelvin sensitivity maps of the microwave background temperature over 200 square degrees of the sky in three frequency bands. We give a brief overview of the scientific motivations for such a map, followed by a design outline of our six-meter custom telescope, an overview of our proposed bolometer array detector technology, and site considerations and ...

  3. Hubble Space Telescope Configuration

    1985-01-01

    This image illustrates the overall Hubble Space Telescope (HST) configuration. The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  4. Alignment telescope for Antares

    The Antares Automatic Alignment System employs a specially designed telescope for alignment of its laser beamlines. There are two telescopes in the system, and since each telescope is a primary alignment reference, stringent boresight accuracy and stability over the focus range were required. Optical and mechanical designs, which meet this requirement as well as that of image quality over a wide wavelength band, are described. Special test techniques for initial assembly and alignment of the telescope are also presented. The telescope, which has a 180-mm aperture FK51-KZF2 type glass doublet objective, requires a boresight accuracy of 2.8 μrad at two focal lengths, and object distances between 11 meters and infinity. Travel of a smaller secondary doublet provides focus from 11 m to infinity with approximately 7.8 m effective focal length. By flipping in a third doublet, the effective focal length is reduced to 2.5 m. Telescope alignment was accomplished by using a rotary air bearing to establish an axis in front of the system and placing the focus of a Laser Unequal Path Interferometer (LUPI) at the image plane

  5. 6M32型氮氢压缩机连杆大瓦失效分析及处理%Analysis and treatment of 6M32-type HN-compressor connecting rod big-tile failure

    陈西国

    2014-01-01

    The paper analyzes causes of connecting rod big-tile failure in 6M32 (50)-160/320 type nitrogen and hydrogen compressor, takes corresponding measures for improvement, and achieves good results.%对6M32(50)-160/320型氮氢压缩机连杆大瓦失效的原因进行分析,采取了相应的改进措施,取得了良好效果。

  6. Far Sidelobes Measurement of the Atacama Cosmology Telescope

    Duenner, Rolando; Gallardo, Patricio; Wollack, Ed; Henriquez, Fernando; Jerez-Hanckes, Carlos

    2012-01-01

    The Atacama Cosmology Telescope (ACT) is a 6m telescope designed to map the Cosmic Microwave Background (CMB) simultaneously at 145GHz, 220 GHz and 280 GHz. Its off-axis Gregorian design is intended to minimize and control the off-axis sidelobe response, which is critical for scientific purposes. The expected sidelobe level for this kind of design is less than -50 dB and can be challenging to measure. Here we present a measurement of the 145 GHz far sidelobes of ACT done on the near-field of the telescope. We used a 1 mW microwave source placed 13 meters away from the telescope and a chopper wheel to produce a varying signal that could be detected by the camera for different orientations of the telescope. The source feed was designed to produce a wide beam profile. Given that the coupling is expected to be dominated by diffraction over the telescope shielding structure, when combined with a measurements of the main beam far field response, these measurement can be used to validate elements of optical design and constrain the level of spurious coupling at large angles. Our results show that the diffractive coupling beyond the ground screen is consistently below -75 dB, satisfying the design expectations.

  7. The South Pole Telescope

    Ruhl, J.E.; Ade, P.A.R.; Carlstrom, J.E.; Cho, H.M.; Crawford,T.; Dobbs, M.; Greer, C.H.; Halverson, N.W.; Holzapfel, W.L.; Lanting,T.M.; Lee, A.T.; Leitch, E.M.; Leong, J.; Lu, W.; Lueker, M.; Mehl, J.; Meyer, S.S.; Mohr, J.J.; Padin, S.; Plagge, T.; Pryke, C.; Runyan, M.C.; Schwan, D.; Sharp, M.K.; Spieler, H.; Staniszewski, Z.; Stark, A.A.

    2004-11-04

    A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required sensitivity and resolution, the telescope design employs an off-axis primary with a 10 m diameter clear aperture. The full aperture and the associated optics will have a combined surface accuracy of better than 20 microns rms to allow precision operation in the submillimeter atmospheric windows. The telescope will be surrounded with a large reflecting ground screen to reduce sensitivity to thermal emission from the ground and local interference. The optics of the telescope will support a square degree field of view at 2mm wavelength and will feed a new 1000-element micro-lithographed planar bolometric array with superconducting transition-edge sensors and frequency-multiplexed readouts. The first key project will be to conduct a survey over 4000 degrees for galaxy clusters using the Sunyaev-Zeldovich Effect. This survey should find many thousands of clusters with a mass selection criteria that is remarkably uniform with redshift. Armed with redshifts obtained from optical and infrared follow-up observations, it is expected that the survey will enable significant constraints to be placed on the equation of state of the dark energy.

  8. Towers for Antarctic Telescopes

    Hammerschlag, R. H.; Bettonvil, F. C. M.; Jägers, A. P. L.; Nielsen, G.

    To take advantage of the exceptional seeing above the boundary layer on Antarctic sites, a high-resolution telescope must be mounted on a support tower. An open transparent tower of framework minimizes the upward temperature-disturbed airflow. A typical minimum height is 30m. The tower platform has to be extremely stable against wind-induced rotational motions, which have to be less than fractions of an arc second, unusually small from a mechanical engineering viewpoint. In a traditional structure, structural deflections result in angular deflections of the telescope platform, which introduce tip and tilt motions in the telescope. However, a structure that is designed to deflect with parallel motion relative to the horizontal plane will undergo solely translation deflections in the telescope platform and thus will not degrade the image. The use of a parallel motion structure has been effectively demonstrated in the design of the 15-m tower for the Dutch Open Telescope (DOT) on La Palma. Special framework geometries are developed, which make it possible to construct high towers in stories having platforms with extreme stability against wind-induced tilt. These geometric solutions lead to constructions, being no more massive than a normal steel framework carrying the same load. Consequently, these lightweight towers are well suited to difficult sites as on Antarctica. A geometry with 4 stories has been worked out.

  9. The Travelling Telescope

    Murabona Oduori, Susan

    2015-08-01

    The telescope has been around for more than 400 years, and through good use of it scientists have made many astonishing discoveries and begun to understand our place in the universe. Most people, however, have never looked through one. Yet it is a great tool for cool science and observation especially in a continent and country with beautifully dark skies. The Travelling Telescope project aims to invite people outside under the stars to learn about those curious lights in the sky.The Travelling Telescope aims to promote science learning to a wide range of Kenyan schools in various locations exchanging knowledge about the sky through direct observations of celestial bodies using state of the art telescopes. In addition to direct observing we also teach science using various hands-on activities and astronomy software, ideal for explaining concepts which are hard to understand, and for a better grasp of the sights visible through the telescope. We are dedicated to promoting science using astronomy especially in schools, targeting children from as young as 3 years to the youth, teachers, their parents and members of the public. Our presentation focuses on the OAD funded project in rural coastal Kenya.

  10. INFLUENCE OF THERMAL DIFFUSION CARBONITRATION AND STRUCTURE OF DIFFUSION COATINGS ON MECHANICAL PROPERTIES OF P6M5 TOOL STEEL

    N. G. Kouhareva

    2014-12-01

    Full Text Available The paper investigates micro-structure, distribution of chemical elements in diffusion carbonitride coatings on P6M5 steel that have been obtained in powder cyanoless media at temperature 450–550 °C, distribution of micro-hardness and also results of the experiments on wear resistance executed at loads of 50 and 400 MPa.Influence of  machining temperature on  dimension and shape of  hardening phases is shown in the paper. The paper also considers influence of these characteristics on mechanical properties of carbonitrated P6M5 steel.

  11. Descriptive Research

    Wigram, Anthony Lewis

    2003-01-01

    starts will allow effect size calculations to be made in order to evaluate effect over time. Given the difficulties in undertaking controlled experimental studies in the creative arts therapies, descriptive research methods offer a way of quantifying effect through descriptive statistical analysis......Descriptive research is described by Lathom-Radocy and Radocy (1995) to include Survey research, ex post facto research, case studies and developmental studies. Descriptive research also includes a review of the literature in order to provide both quantitative and qualitative evidence of the effect...... of music therapy with a specific population (Gold, Voracek & Wigram, Wigram, 2002). The collection of such evidence, through surveys of the literature and documentation of music therapy studies that show effect with a specified population are becoming increasingly important in order to underpin music...

  12. Telescopes and Techniques

    Kitchin, C R

    2013-01-01

    Telescopes and Techniques has proved itself in its first two editions, having become probably one of the most widely used astronomy texts, both for amateur astronomers and astronomy and astrophysics undergraduates. Both earlier editions of the book were widely used for introductory practical astronomy courses in many universities. In this Third Edition the author guides the reader through the mathematics, physics and practical techniques needed to use today's telescopes (from the smaller models to the larger instruments installed in many colleges) and how to find objects in the sky. Most of the physics and engineering involved is described fully and requires little prior knowledge or experience. Both visual and electronic imaging techniques are covered, together with an introduction to how data (measurements) should be processed and analyzed. A simple introduction to radio telescopes is also included. Brief coverage of the more advanced topics of photometry and spectroscopy are included, but mainly to enable ...

  13. Integrated Modeling of Telescopes

    Andersen, Torben

    2011-01-01

    With increasingly complex and costly opto-mechanical systems, there is a growing need for reliable computer modeling and simulation. The field of integrated modeling, combining optics, mechanics, control engineering, and other disciplines, is the subject of this book. Although the book primarily focuses on ground-based optical telescopes, the techniques introduced are applicable also to other wavelengths and to other opto-mechanical applications on the ground or in space. Basic tools of integrated modeling are introduced together with concepts of ground-based telescopes. Modeling of optical systems, structures, wavefront control systems with emphasis on segmented mirror control, and active and adaptive optics are described together with a variety of noise sources; many examples are included in this book. Integrated Modeling of Telescopes is a text for physicists and engineers working in the field of opto-mechanical design and wavefront control, but it will also be valuable as a textbook for PhD students.

  14. The Sardinia Radio Telescope

    D'Amico, Nichi

    2011-08-01

    We present the status of the Sardinia Radio Telescope (SRT) project, a new general purpose, fully steerable 64 m diameter parabolic radio telescope under construction in Sardinia. The instrument is funded by Italian Ministry of University and Research (MIUR), by the Sardinia Regional Government (RAS), and by the Italian Space Agency (ASI), and it is charge to three research structures of the National Institute for Astrophysics (INAF): the Institute of Radio Astronomy of Bologna, the Cagliari Astronomical Observatory (in Sardinia), and the Arcetri Astrophysical Observatory in Florence. The radio telescope has a shaped Gregorian optical configuration with a 8 m diameter secondary mirror and additional Beam-Wave Guide (BWG) mirrors. One of the most challenging feature of SRT is the active surface of the primary reflector which provides good efficiency up to about 100 GHz. This paper reports on the most recent advances of the construction.

  15. Configurable Aperture Space Telescope

    Ennico, Kimberly; Bendek, Eduardo

    2015-01-01

    In December 2014, we were awarded Center Innovation Fund to evaluate an optical and mechanical concept for a novel implementation of a segmented telescope based on modular, interconnected small sats (satlets). The concept is called CAST, a Configurable Aperture Space Telescope. With a current TRL is 2 we will aim to reach TLR 3 in Sept 2015 by demonstrating a 2x2 mirror system to validate our optical model and error budget, provide straw man mechanical architecture and structural damping analyses, and derive future satlet-based observatory performance requirements. CAST provides an alternative access to visible and/or UV wavelength space telescope with 1-meter or larger aperture for NASA SMD Astrophysics and Planetary Science community after the retirement of HST

  16. A nomogram calculating the features of the astronomical telescope (French Title: Nomogramme pour le calcul des caracteristiques de l'astroscope)

    Pelat, A.

    2006-10-01

    This article focuses on the theoretical study, drawing up and use of a cartesian nomogram to calculate the features of an astronomical telescope.It also includes a description of Christiaan Huygens's 'pipeless' astronomical telescope.

  17. New Vacuum Solar Telescope

    2011-01-01

    With its pure aperture up to 985mm, the New Vacuum Solar Telescope of China (NVST) has become the world's biggest vacuum solar telescope. The main science task of NVST is the high-resolution observation of photosphere and chromosphere including their fine structure of magnetic field on the sun. The NVST was equipped with many new technologies and powerful instruments, such as an adaptive optical system, a polarization analyzer, two vertical spectrographs, a high-resolution image system and a very narrow Ha filter (0.125A).

  18. Athermal laser launch telescopes

    Kamphues, F.G.; Henselmans, R.; Rijnveld, N.; Lemmen, M.H.J.; Doelman, N.J.; Nijkerk, M.D.

    2011-01-01

    ESO has developed a concept for a compact laser guide star unit for use in future Adaptive Optics (AO) systems. A small powerful laser is combined with a telescope that launches the beam, creating a single modular unit that can be mounted directly on a large telescope. This approach solves several of the stability problems experienced with a number of first generation laser guide star systems around the world. Four of these compact laser guide stars will be used for the new VLT 4LGSF Adaptive...

  19. The MAGIC Telescope Project

    Up to now the 20-300 GeV energy range has been inaccessible to gamma-ray astronomy. Here we report on a design for a 17-m φ air Cerenkov telescope, dubbed MAGIC telescope, which will have a threshold of 20 GeV, a large collection area of > 105 m2 and a high gamma/hadron separation power. It is estimated that the hardware investments would be about 3.5 M$ and 2.5-3.5 years would be needed for the construction. (author)

  20. Proton beam of 2 MeV 1.6 mA on a tandem accelerator with vacuum insulation

    A source of epithermal neutrons based on a tandem accelerator with vacuum insulation for boron neutron capture therapy of malignant tumors was proposed and constructed. Stationary proton beam with 2 MeV energy, 1.6 mA current, 0.1% energy monochromaticity and 0.5% current stability has just been obtained

  1. Taiwan Automated Telescope Network

    Dean-Yi Chou

    2010-01-01

    can be operated either interactively or fully automatically. In the interactive mode, it can be controlled through the Internet. In the fully automatic mode, the telescope operates with preset parameters without any human care, including taking dark frames and flat frames. The network can also be used for studies that require continuous observations for selected objects.

  2. A Simple "Tubeless" Telescope

    Straulino, S.; Bonechi, L.

    2010-01-01

    Two lenses make it possible to create a simple telescope with quite large magnification. The set-up is very simple and can be reproduced in schools, provided the laboratory has a range of lenses with different focal lengths. In this article, the authors adopt the Keplerian configuration, which is composed of two converging lenses. This instrument,…

  3. The Telescope (to 1950)

    Jarrell, R.; Murdin, P.

    2000-11-01

    The TELESCOPE was the single greatest technical innovation in the history of astronomy, transforming it from a naked-eye study of celestial motions into a physical science. It revealed to humans a far richer and more complex universe than ever imagined. Its history proceeded in stages: a technological discovery led to a series of improvements until an impasse was reached. Another discovery would ...

  4. Exploring Galileo's Telescope

    Straulino, Samuele; Terzuoli, Alessandra

    2010-01-01

    In the first months of 2009, the International Year of Astronomy, the authors developed an educational project for middle-level students connected with the first astronomical discoveries that Galileo Galilei (1564-1642) made 400 years ago. The project included the construction of a basic telescope and the observation of the Moon. The project, if…

  5. The Liverpool Telescope

    Smith, Robert J.; Bates, S. D.; Clay, Neil R.; Fraser, Stephen N.; Marchant, J. M.; Mottram, C. J.; Steele, I. A.; Tomlinson, M. D.

    2011-03-01

    The Liverpool Telescope (LT) is a fully robotic 2m optical telescope at a world-class observatory site. It runs autonomously without direct human control either on site or remotely. It is not operated primarily for a single science project, but rather is a common-user facility, time allocated by an open, peer-review process and conducting a variety of optical and IR imaging, spectroscopic and polarimetric programs. This paper describes some of aspects of the site infrastructure and instrument suite designed specifically to support robust and reliable unsupervised operations. Aside from the telescope hardware, the other aspect of robotic operations is the mechanisms whereby users interact with the telescope and its automated scheduler. We describe how these have been implemented for the LT. Observing routinely since 2004, the LT has demonstrated it is possible to operate a large, common-user robotic observatory. Making the most of the flexibility afforded by fully robotic operations, development continues in collaboration with both observers and other observatories to develop observing modes to enable new science across the broad discipline of time-domain astrophysics.

  6. THE LARGE MILLIMETER TELESCOPE

    D. H. Hughes

    2009-01-01

    Full Text Available This paper, presented on behalf of the Large Millimeter Telescope (LMT project team, describes the status and near-term plans for the telescope and its initial instrumentation. The LMT is a bi-national collaboration between M xico and the USA, led by the Instituto Nacional de Astrof sica, ptica y Electr nica (INAOE and the University of Massachusetts at Amherst, to construct, commission and operate a 50 m diameter millimeterwave radio telescope. Construction activities are nearly complete at the LMT site, at an altitude of 4600 m on the summit of Sierra Negra, an extinct volcano in the Mexican state of Puebla. Full movement of the telescope, under computer control in both azimuth and elevation, has been achieved. First-light at centimeter wavelengths on astronomical sources was obtained in November 2006. Installation of precision surface segments for millimeter-wave operation is underway, with the inner 32 m diameter of the surface now complete and ready to be used to obtain rst-light at millimeter wavelengths in 2008. Installation of the remainder of the re ector will continue during the next year and be completed in 2009 for nal commissioning of the antenna. The full LMT antenna, out ted with its initial complement of scienti c instruments, will be a world-leading scienti c research facility for millimeter-wave astronomy.

  7. Hubble Space Telescope: The Telescope, the Observations & the Servicing Mission

    1999-11-01

    NICMOS enabling it to resume operation, and install a new set of solar panels. Replacement of the thermal insulation will continue and the telescope will be reboosted to a higher orbit. The plans for the fourth Servicing Mission are preliminary at this time, but two new science instruments are being developed for that mission: Cosmic Origins Spectrograph (COS), which will replace COSTAR, and Wide Field Camera 3 (WFC3), which will replace WFPC2. It is planned to retrieve Hubble at the end of its life (around 2010) and bring it back to Earth. In the future ESA may have the opportunity to continue its collaboration with NASA on the Next Generation Space Telescope (NGST), which in many ways can be seen as Hubble's successor. The plan is to launch NGST in 2008, and ESA is currently considering a possible role in the project. Piero Benvenuti concludes: "The European Space Agency, in deciding to join NASA on the HST Project, made a very successful investment on behalf of European science. Today, NASA would not consider proceeding alone on the continued operation of HST or on the design of NGST. Not just because of the benefit of shared cost, but mainly because of the intellectual contribution by the European astronomers, who have made such effective scientific use of HST." Hubble Space Telescope - Fact sheet Description The Hubble Space Telescope (HST) is a co-operation between ESA and NASA. It is a long-term space-based observatory. Its observations are carried out in visible, infrared and ultraviolet light. HST has in many ways revolutionised modern astronomy, being a highly efficient tool for making new discoveries, but also by driving astronomical research in general. Objective HST was designed to take advantage of being above the Earth's disturbing atmosphere, and thereby providing astronomers with observations of very high resolution - opening new windows on planets, stars and galaxies. HST was designed as a flagship mission of the highest standard, and has served to pave

  8. The Greenland Telescope

    Grimes, Paul; Blundell, Raymond

    2012-09-01

    In the spring of 2010, the Academia Sinica Institute of Astronomy and Astrophysics, and the Smithsonian Astrophysical Observatory, acquired the ALMA North America prototype antenna - a state-of-the-art 12-m diameter dish designed for submillimeter astronomy. Together with the MIT-Haystack Observatory and the National Radio Astronomy Observatory, the plan is to retrofit this antenna for cold-weather operation and equip it with a suite of instruments designed for a variety of scientific experiments and observations. The primary scientific goal is to image the shadow of the Super-Massive Black Hole in M87 in order to test Einstein’s theory of relativity under extreme gravity. This requires the highest angular resolution, which can only be achieved by linking this antenna with others already in place to form a telescope almost the size of the Earth. We are therefore developing plans to install this antenna at the peak of the Greenland ice-sheet. This location will produce an equivalent North-South separation of almost 9,000 km when linked to the ALMA telescope in Northern Chile, and an East-West separation of about 6,000 km when linked to SAO and ASIAA’s Submillimeter Array on Mauna Kea, Hawaii, and will provide an angular resolution almost 1000 times higher than that of the most powerful optical telescopes. Given the quality of the atmosphere at the proposed telescope location, we also plan to make observations in the atmospheric windows at 1.3 and 1.5 THz. We will present plans to retrofit the telescope for cold-weather operation, and discuss potential instrumentation and projected time-line.

  9. Southern Fireworks above ESO Telescopes

    1999-05-01

    - the PLANET observers turned their telescope and quickly obtained a series of CCD images in visual light of the sky region where the gamma-ray burst was detected, then shipped them off electronically to their Dutch colleagues [3]. Comparing the new photos with earlier ones in the digital sky archive, Vreeswijk, Galama and Rol almost immediately discovered a new, relatively bright visual source in the region of the gamma-ray burst, which they proposed as the optical counterpart of the burst, cf. their dedicated webpage at http://www.astro.uva.nl/~titus/grb990510/. The team then placed a message on the international Gamma-Ray Burster web-noteboard ( GCN Circular 310), thereby alerting their colleagues all over the world. One hour later, the narrow-field instruments on BeppoSax identified a new X-Ray source at the same location ( GCN Circular 311), thus confirming the optical identification. All in all, a remarkable synergy of human and satellite resources! Observations of GRB 990510 at ESO Vreeswijk, Galama and Rol, in collaboration with Nicola Masetti, Eliana Palazzi and Elena Pian of the BeppoSAX GRB optical follow-up team (led by Filippo Frontera ) and the Huntsville optical follow-up team (led by Chryssa Kouveliotou ), also contacted the European Southern Observatory (ESO). Astronomers at this Organization's observatories in Chile were quick to exploit this opportunity and crucial data were soon obtained with several of the main telescopes at La Silla and Paranal, less than 14 hours after the first detection of this event by the satellite. ESO PR Photo 22a/99 ESO PR Photo 22a/99 [Preview - JPEG: 211 x 400 pix - 72k] [Normal - JPEG: 422 x 800 pix - 212k] [High-Res - JPEG: 1582 x 3000 pix - 2.6M] ESO PR Photo 22b/99 ESO PR Photo 22b/99 [Preview - JPEG: 400 x 437 pix - 297k] [Normal - JPEG: 800 x 873 pix - 1.1M] [High-Res - JPEG: 2300 x 2509 pix - 5.9M] Caption to PR Photo 22a/99 : This wide-field photo was obtained with the Wide-Field Imager (WFI) at the MPG/ESO 2.2-m

  10. Ultra high throughput four-reflection x-ray telescope for high resolution spectroscopy

    Tawara, Yuzuru; Mitsuishi, Ikuyuki; Babazaki, Yasunori; Nakamichi, Ren; Bandai, Ayako

    2015-09-01

    The first application of four-times reflection X-ray optics is planned for the DIOS mission, in which very soft X-ray observation is expected. On the other hand, effective area of the telescope for higher X-ray energy (E < 10 keV) including iron K emission lines has been so far limited to about 1000 cm2 for assumed several meter focal length. However, if we introduce four-reflection optics to this energy range, we can get several times large effective area for single telescope with same several meter focal length. To prove this possibility, we performed ray tracing simulation for four-reflection telescope with 6 m focal length and found that effective area of 3100 cm2 at 6 keV can be obtained for single telescope. In this paper, we will discuss about other telescope performances, mechanical properties and application to fine spectroscopic mission using X-ray micro-calorimeter.

  11. Research on Marching of 6M552C Diesel Engine with Turbocharger%6M552C 型柴油机与增压器匹配试验研究

    夏纯耀

    2014-01-01

    With the requirement of mechanical equipment replacement,based on the marching theory of diesel engine and turbocharger,the marching calculation flow and relative parameters are defined in the paper,which can be used to select the size and type of the desired turbocharger for 6M552C diesel engine.The test results are analyzed and it shows that the selected turbocharger works well.This successful marching of 6M552C diesel engine and turbocharger can provide some reference and guid-ance to the marching work.%面对机械设备更新的要求,基于柴油机和涡轮增压器匹配的理论,确定了匹配计算的参数和流程,并进行了相关的计算,选出了6M552C 型柴油机合适的替代增压器,并对试验结果进行了比较,表明所选增压器符合要求。

  12. NRAO Green Bank Telescope (GBT)

    Federal Laboratory Consortium — The largest fully steerable telescope in the world - the Robert C. Byrd Green Bank Telescope, began observations in Green Bank, West Virginia in 2000and is a wonder...

  13. Optical Space Telescope Assembly Project

    National Aeronautics and Space Administration — The Optical Space Telescope Assembly (OSTA) task is to demonstrate the technology readiness of assembling large space telescopes on orbit in 2015. This task is an...

  14. Anaphoric Descriptions

    Beller, Charley

    2013-01-01

    The study of definite descriptions has been a central part of research in linguistics and philosophy of language since Russell's seminal work "On Denoting" (Russell 1905). In that work Russell quickly dispatches analyses of denoting expressions with forms like "no man," "some man," "a man," and "every…

  15. Platform Deformation Refined Pointing and Phase Correction for the AMiBA Hexapod Telescope

    Koch, Patrick M; Chang, Yu-Yen; Huang, Yau-De; Raffin, Philippe; Chen, Ke-Yung; Chereau, Guillaume; Chen, Ming-Tang; Ho, Paul T P; Huang, Chih-Wie; Ibanez-Romano, Fabiola; Jiang, Homin; Liao, Yu-Wei; Lin, Kai-Yang; Liu, Guo-Chin; Molnar, Sandor M; Nishioka, Hiroaki; Umetsu, Keiichi; Wang, Fu-Cheng; Wu, Jiun-Huei Proty; Altamirano, Pablo; Chang, Chia-Hao; Chang, Shu-Hao; Chang, Su-Wei; Han, Chi-Chiang; Kubo, Derek; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter

    2009-01-01

    The Array for Microwave Background Anisotropy (AMiBA) is a radio interferometer for research in cosmology, currently operating 7 0.6m diameter antennas co-mounted on a 6m diameter platform driven by a hexapod mount. AMiBA is currently the largest hexapod telescope. We briefly summarize the hexapod operation with the current pointing error model. We then focus on the upcoming 13-element expansion with its potential difficulties and solutions. Photogrammetry measurements of the platform reveal deformations at a level which can affect the optical pointing and the receiver radio phase. In order to prepare for the 13-element upgrade, two optical telescopes are installed on the platform to correlate optical pointing tests. Being mounted on different locations, the residuals of the two sets of pointing errors show a characteristic phase and amplitude difference as a function of the platform deformation pattern. These results depend on the telescope's azimuth, elevation and polarization position. An analytical model ...

  16. Progress in Space Solar Telescope

    2009-01-01

    In this paper we will summarize the progress in the development of the Chinese Space Solar Telescope (SST) during the past few years. The main scientific objective of SST is to observe the fundamental structure of solar magnetic field with its 1-m optical telescope. The success of 1-m Swedish Solar Telescope and Hinode underscores the importance of this 1-m space telescope. In addition, some key technical problems have been solved.

  17. Lunar transit telescope lander design

    Omar, Husam A.

    The Program Development group at NASA's Marshall Space Flight Center has been involved in studying the feasibility of placing a 16 meter telescope on the lunar surface to scan the skies using visible/ Ultraviolet/ Infrared light frequencies. The precursor telescope is now called the TRANSIT LUNAR TELESCOPE (LTT). The Program Development Group at Marshall Space Flight Center has been given the task of developing the basic concepts and providing a feasibility study on building such a telescope. The telescope should be simple with minimum weight and volume to fit into one of the available launch vehicles. The preliminary launch date is set for 2005. A study was done to determine the launch vehicle to be used to deliver the telescope to the lunar surface. The TITAN IV/Centaur system was chosen. The engineering challenge was to design the largest possible telescope to fit into the TITAN IV/Centaur launch system. The telescope will be comprised of the primary, secondary and tertiary mirrors and their supporting system in addition to the lander that will land the telescope on the lunar surface and will also serve as the telescope's base. The lunar lander should be designed integrally with the telescope in order to minimize its weight, thus allowing more weight for the telescope and its support components. The objective of this study were to design a lander that meets all the constraints of the launching system. The basic constraints of the TITAN IV/Centaur system are given.

  18. Decrease in transient receptor potential melastatin 6 mRNA stability caused by rapamycin in renal tubular epithelial cells.

    Ikari, Akira; Sanada, Ayumi; Sawada, Hayato; Okude, Chiaki; Tonegawa, Chie; Sugatani, Junko

    2011-06-01

    Rapamycin, an inhibitor of mammalian target of rapamycin (mTOR), is used in treatments for transplantation and cancer. Rapamycin causes hypomagnesemia, although precisely how has not been examined. Here, we investigated the effect of rapamycin on the expression of transient receptor potential melastatin 6 (TRPM6), a Mg2+ channel. Rapamycin and LY-294002, an inhibitor of phosphatidilinositol-3 kinase (PI3K) located upstream of mTOR, inhibited epidermal growth factor (EGF)-induced expression of the TRPM6 protein without affecting TRPM7 expression in rat renal NRK-52E epithelial cells. Both rapamycin and LY-294002 decreased EGF-induced Mg2+ influx. U0126, a MEK inhibitor, inhibited EGF-induced increases in c-Fos, p-ERK, and TRPM6 levels. In contrast, neither rapamycin nor LY-294002 inhibited EGF-induced increases in p-ERK and c-Fos levels. EGF increased p-Akt level, an effect inhibited by LY-294002 and 1L-6-hydroxymethyl-chiro-inositol2-[(R)-2-O-methyl-3-O-octadecylcarbonate] (Akt inhibitor). Akt inhibitor decreased TRPM6 level similar to rapamycin and LY-294002. These results suggest that a PI3K/Akt/mTOR pathway is involved in the regulation of TRPM6 expression. Rapamycin inhibited the EGF-induced increase in TRPM6 mRNA but did not inhibit human TRPM6 promoter activity. In the presence of actinomycin D, a transcriptional inhibitor, rapamycin accelerated the decrease in TRPM6 mRNA. Rapamycin decreased the expression and activity of a luciferase linked with the 3'-untranslated region of human TRPM6 mRNA. These results suggest that TRPM6 expression is up-regulated by a PI3K/Akt/mTOR pathway and rapamycin reduces TRPM6 mRNA stability, resulting in a decrease in the reabsorption of Mg2+. PMID:21073857

  19. Everyday Radio Telescope

    Mandal, Pranshu; Kumar, Pratik; Yelikar, Anjali; Soni, Kanchan; T, Vineeth Krishna

    2016-01-01

    We have developed an affordable, portable college level radio telescope for amateur radio astronomy which can be used to provide hands-on experience with the fundamentals of a radio telescope and an insight into the realm of radio astronomy. With our set-up one can measure brightness temperature and flux of the Sun at 11.2 GHz and calculate the beam width of the antenna. The set-up uses commercially available satellite television receiving system and parabolic dish antenna. We report the detection of point sources like Saturn and extended sources like the galactic arm of the Milky way. We have also developed python pipeline, which are available for free download, for data acquisition and visualization.

  20. Telescopic horizon scanning.

    Koenderink, Jan

    2014-12-20

    The problem of "distortionless" viewing with terrestrial telescopic systems (mainly "binoculars") remains problematic. The so called "globe effect" is only partially counteracted in modern designs. Theories addressing the phenomenon have never reached definitive closure. In this paper, we show that exact distortionless viewing with terrestrial telescopic systems is not possible in general, but that it is in principle possible in-very frequent in battle field and marine applications-the case of horizon scanning. However, this involves cylindrical optical elements. For opto-electronic systems, a full solution is more readily feasible. The solution involves a novel interpretation of the relevant constraints and objectives. For final design decisions, it is not necessary to rely on a corpus of psychophysical (or ergonomic) data, although one has to decide whether the instrument is intended as an extension of the eye or as a "pictorial" device. PMID:25608206

  1. Telescope enclosure flow visualization

    Forbes, Fred F.; Wong, Woon-Yin; Baldwin, Jack; Siegmund, Walter A.; Limmongkol, Siriluk; Comfort, Charles H.

    1991-12-01

    Dome-induced thermal disturbances that degrade seeing can originate when temperature differences exist between the interior and exterior of a telescope enclosure. It is important to design enclosures which minimize the effect. One design aid is to model the enclosure and study the flow patterns in and around the model at various angles to the flow direction. We have used a water tunnel and models of spherical, octagonal, and rectangular enclosures to investigate the flow characteristics as a function of angle and venting configuration. In addition to a large video data-base, numerical results yield flushing times for all models and all venting arrangements. We have also investigated the comparative merits of passive venting as opposed to active forced flow circulation for the 4m telescope enclosure at the NOAO Cerro Tololo Interamerican Observatory at La Serena, Chile. Finally, the flow characteristics of a tracking half-shroud were studied as a possible shield for the enclosureless case.

  2. Comparing NEO Search Telescopes

    Myhrvold, Nathan

    2015-01-01

    Multiple terrestrial and space-based telescopes have been proposed for detecting and tracking near-Earth objects (NEOs). Detailed simulations of the search performance of these systems have used complex computer codes that are not widely available, which hinders accurate cross- comparison of the proposals and obscures whether they have consistent assumptions. Moreover, some proposed instruments would survey infrared (IR) bands, whereas others would operate in the visible band, and differences among asteroid thermal and visible light models used in the simulations further complicate like-to-like comparisons. I use simple physical principles to estimate basic performance metrics for the ground-based Large Synoptic Survey Telescope and three space-based instruments - Sentinel, NEOCam, and a Cubesat constellation. The performance is measured against two different NEO distributions, the Bottke et al. distribution of general NEOs, and the Veres et al. distribution of earth impacting NEO. The results of the comparis...

  3. The Bionic Telescope

    Woolf, Neville

    2009-05-01

    Four hundred years after children in a spectacle makers workshop accidentally discovered the telescope, the development of this device has been a continuous replacement of the ``natural'' by the deliberate. The human eye is gone. The lens is gone. The tube is gone. The dome is on the verge of going. The size of the optics are ceasing to be set by transportation limits. Adaptive optics are preferred to stable optics. We deliberately break the Lagrange invariant. We focus on lasers instead of stars, and natural observing environments are being replaced by adaptive environments. The goals for the new ground based telescope encompass the oldest and newest ideas, to find signs of life elsewhere, and to find how all the universe developed.

  4. The ANTARES Neutrino Telescope

    Perrina, Chiara

    2015-01-01

    At about 40 km off the coast of Toulon (France), anchored at 2475 m deep in the Mediterranean Sea, there is ANTARES: the first undersea neutrino telescope and the only one currently operating. The detector consists of 885 photomultiplier tubes arranged into 12 strings of 450-metres high, with the aim to detect the Cherenkov light induced by the charged superluminal interaction products of neutrinos. Its main scientific target is the search for high-energy (TeV and beyond) neutrinos from cosmic accelerators, as predicted by hadronic interaction models, and the measurement of the cosmic neutrino diffuse flux, focusing in particular on events coming from below the horizon (up-going events) in order to significantly reduce the atmospheric muons background. Thanks to the development of a strategy for the identification of neutrinos coming from above the horizon (down-going events) the field of view of the telescope will be extended.

  5. [Galileo and his telescope].

    Strebel, Christoph

    2006-01-01

    Galileo's publication of observations made with his newly reinvented telescope provoked a fierce debate. In April 1610 Martinus Horky, a young Bohemian astronomer, had an opportunity to make his own observations with Galileo's telescope in the presence of Antonio Magini and other astronomers. Horky and the other witnesses denied the adequacy of Galileo's telescope and therefore the bona fides of his discoveries. Kepler conjectured Horky as well as all his witnesses to be myopic. But Kepler's objection could not stop the publication of Horky's Peregrinatio contra nuncium sidereum (Modena, 1610), the first printed refutation of Galileo's Sidereus nuncius. In his treatise, Horky adresses four questions: 1) Do the four newly observed heavenly bodies actually exist? Horky denies their existence on various grounds: a) God, as every astronomer teaches, has created only seven moveable heavenly bodies and astronomical knowledge originates in God, too. b) Heavenly bodies are either stars or planets. Galileo's moveable heavenly bodies fit into neither category. c) If they do exist, why have they not already been observed by other scholars? Horky concludes that there are no such heavenly bodies. 2) What are these phenomena? They are purely artefactual, and produced by Galileo's telescope. 3) How are they like? Galileo's "stars" are so small as to be almost invisible. Galileo claims that he has measured their distances from each other. This however is impossible due to their diminutive size and other observational problems. Hence, Galileo's claim is a further proof that he is a fraud. 4) Why are they? For Galileo they are a chance to earn money but for astronomers like Horky they are a reason to offer thanks and honour to God. Horky's treatise was favourably received by the enemies of Galileo. But Kepler's critique was devastating. After calling on Kepler in Prague, Horky had to revoke the contents of his book. PMID:16929794

  6. TELESCOPE sipping in PWRs

    Due to the experience accumulated at ABB Atom in the early seventies, the company could use the know-how and available data for further development work and in the nineties introduced an advanced burst can detection method, the TELESCOPE sipping. The device and the method were successfully tested in November 1996 in pilot tests performed at the Grohnde nuclear power plant using a number of suitable fuel assemblies. (orig./CB)

  7. Workshop: Neutrino telescopes

    Despite being the most elusive of the known particles, neutrinos provide vital new physics insights. Most neutrino knowledge so far has come from studies using beams from reactors and accelerators, but in recent years important new contributions have resulted from investigation of natural neutrinos from cosmic rays, nearby stars (the sun), or distant sources, such as the 1987 supernova. The supernova observations marked the start of a new era in neutrino astronomy, but neutrino telescopes were anyway assured of an important ongoing role

  8. Offset guider for the prime focus of the 3.9-meter Anglo-Australian telescope

    The automatic offset guider at the prime focus of the AAT is described. A description of the guider and its organization in the telescope's computerized drive system is followed by the initial results obtained with it

  9. The GCT camera for the Cherenkov Telescope Array

    Brown, Anthony M; Allan, D; Amans, J P; Armstrong, T P; Balzer, A; Berge, D; Boisson, C; Bousquet, J -J; Bryan, M; Buchholtz, G; Chadwick, P M; Costantini, H; Cotter, G; Daniel, M K; De Franco, A; De Frondat, F; Dournaux, J -L; Dumas, D; Fasola, G; Funk, S; Gironnet, J; Graham, J A; Greenshaw, T; Hervet, O; Hidaka, N; Hinton, J A; Huet, J -M; Jegouzo, I; Jogler, T; Kraus, M; Lapington, J S; Laporte, P; Lefaucheur, J; Markoff, S; Melse, T; Mohrmann, L; Molyneux, P; Nolan, S J; Okumura, A; Osborne, J P; Parsons, R D; Rosen, S; Ross, D; Rowell, G; Sato, Y; Sayede, F; Schmoll, J; Schoorlemmer, H; Servillat, M; Sol, H; Stamatescu, V; Stephan, M; Stuik, R; Sykes, J; Tajima, H; Thornhill, J; Tibaldo, L; Trichard, C; Vink, J; Watson, J J; White, R; Yamane, N; Zech, A; Zink, A; Zorn, J

    2016-01-01

    The Gamma-ray Cherenkov Telescope (GCT) is proposed for the Small-Sized Telescope component of the Cherenkov Telescope Array (CTA). GCT's dual-mirror Schwarzschild-Couder (SC) optical system allows the use of a compact camera with small form-factor photosensors. The GCT camera is ~0.4 m in diameter and has 2048 pixels; each pixel has a ~0.2 degree angular size, resulting in a wide field-of-view. The design of the GCT camera is high performance at low cost, with the camera housing 32 front-end electronics modules providing full waveform information for all of the camera's 2048 pixels. The first GCT camera prototype, CHEC-M, was commissioned during 2015, culminating in the first Cherenkov images recorded by a SC telescope and the first light of a CTA prototype. In this contribution we give a detailed description of the GCT camera and present preliminary results from CHEC-M's commissioning.

  10. The first GCT camera for the Cherenkov Telescope Array

    De Franco, A.; Allan, D.; Armstrong, T.; Ashton, T.; Balzer, A.; Berge, D.; Bose, R.; Brown, A.M.; Buckley, J.; Chadwick, P.M.; Cooke, P.; Cotter, G.; Daniel, M.K.; Funk, S.; Greenshaw, T.; Hinton, J.; Kraus, M.; Lapington, J.; Molyneux, P.; Moore, P.; Nolan, S.; Okumura, A.; Ross, D.; Rulten, C.; Schmoll, J.; Schoorlemmer, H.; Stephan, M.; Sutcliffe, P.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Varner, G.; Watson, J.; Zink, A.

    2015-01-01

    The Gamma Cherenkov Telescope (GCT) is proposed to be part of the Small Size Telescope (SST) array of the Cherenkov Telescope Array (CTA). The GCT dual-mirror optical design allows the use of a compact camera of diameter roughly 0.4 m. The curved focal plane is equipped with 2048 pixels of ~0.2{\\deg} angular size, resulting in a field of view of ~9{\\deg}. The GCT camera is designed to record the flashes of Cherenkov light from electromagnetic cascades, which last only a few tens of nanoseconds. Modules based on custom ASICs provide the required fast electronics, facilitating sampling and digitisation as well as first level of triggering. The first GCT camera prototype is currently being commissioned in the UK. On-telescope tests are planned later this year. Here we give a detailed description of the camera prototype and present recent progress with testing and commissioning.

  11. GREGOR: the New German Solar Telescope

    Balthasar, H.; von der Lühe, O.; Kneer, F.; Staude, J.; Volkmer, R.; Berkefeld, T.; Caligari, P.; Collados, M.; Halbgewachs, C.; Heidecke, F.; Hofmann, A.; Klvaňa, Miroslav; Nicklas, H.; Popow, E.; Puschmann, K.G.; Schmidt, W.; Sobotka, Michal; Soltau, D.; Strassmeier, K.G.; Wittmann, A.

    San Francisco: Astronomical Society of the Pacific, 2007 - (Heinzel, P.; Dorotovič, I.; Rutten, R.), s. 605-610. (ASP Conference Series. 368). ISBN 978-1-583812-36-5. [Solar Physics Meeting. Coimbra (PT), 09.10.2006-13.10.2006] Grant ostatní: EU(XE) HPRN-CT-2002-00313 Institutional research plan: CEZ:AV0Z10030501 Source of funding: V - iné verejné zdroje Keywords : telescope * description Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  12. Spitzer Space Telescope : observatory desciption and performance

    Patel, Keyur C.; Spath, Stuart R.

    2004-01-01

    The Spitzer Space Telescope, the last of the four Great Observatories commissioned by the National Aeronautics and Space Administration, was successfully launched on August 25, 2003 from Kennedy Space Center. The engineering systems for Spitzer were developed by the Jet Propulsion Laboratory, Lockheed Martin Space Systems Company, and Ball Aerospace & Technology Corp. This paper provides an overview of Spitzer, a technical description of all the engineering subsystems, and the associated challenges involved in developing them to satisfy the mission requirements. In addition, this paper describes the performance of the engineering subsystems during the In-Orbit Checkout phase, the Science Verification phase, and the early portions of the Nominal Mission.

  13. Star tracker for the Apollo telescope mount

    Lee, C. E.

    1971-01-01

    The star tracker for the Apollo Telescope Mount (ATM) has been designed specifically to meet the requirements of the Skylab vehicle and mission. The functions of the star tracker are presented, as well as descriptions of the optical-mechanical assembly (OMA) and the star tracker electronics (STE). Also included are the electronic and mechanical specifications, interface and operational requirements, support equipment and test requirements, and occultation information. Laboratory functional tests, environmental qualification tests, and life tests have provided a high confidence factor in the performance of the star tracker in the laboratory and on the Skylab mission.

  14. Description Logics

    Baader, Franz

    Description Logics (DLs) are a well-investigated family of logic-based knowledge representation formalisms, which can be used to represent the conceptual knowledge of an application domain in a structured and formally well-understood way. They are employed in various application domains, such as natural language processing, configuration, and databases, but their most notable success so far is the adoption of the DL-based language OWL as standard ontology language for the semantic web.

  15. Scientific impact of large telescopes

    Sánchez, S F

    2000-01-01

    The scientific impacts of telescopes worldwide have been compared on the basis of their contributions to (a) the 1000 most-cited astronomy papers published 1991-8 (125 from each year), and (b) the 452 astronomy papers published in Nature 1989-98. 1-m and 2-m ground-based telescopes account for \\~5% of the citations to the top-cited papers, 4-m telescopes 10%, Keck I/II 4%, sub-mm and radio telescopes 4%, HST 8%, other space telescopes 23%. The remaining citations are mainly to theoretical and review papers. The strong showing by 1-m and 2-m telescopes in the 1990s augurs well for the continued scientific impact of 4-m telescopes in the era of 8-m telescopes. The impact of individual ground-based optical telescopes is proportional to collecting area (and approximately proportional to capital cost). The impacts of the various 4-m telescopes are similar, with CFHT leading in citation counts, and WHT in Nature papers. HST has about 15 times the citation impact of a 4-m ground-based telescope, but cost >100 times ...

  16. The Planck Telescope reflectors

    Stute, Thomas

    2004-09-01

    The mechanical division of EADS-Astrium GmbH, Friedrichshafen is currently engaged with the development, manufacturing and testing of the advanced dimensionally stable composite reflectors for the ESA satellite borne telescope Planck. The objective of the ESA mission Planck is to analyse the first light that filled the universe, the cosmic microwave background radiation. Under contract of the Danish Space Research Institute and ESA EADS-Astrium GmbH is developing the all CFRP primary and secondary reflectors for the 1.5-metre telescope which is the main instrument of the Planck satellite. The operational frequency ranges from to 25 GHz to 1000 GHz. The demanding high contour accuracy and surface roughness requirements are met. The design provides the extreme dimensional stability required by the cryogenic operational environment at around 40 K. The elliptical off-axis reflectors display a classical lightweight sandwich design with CFRP core and facesheets. Isostatic mounts provide the interfaces to the telescope structure. Protected VDA provides the reflecting surface. The manufacturing is performed at the Friedrichshafen premises of EADS-Space Transportation GmbH, the former Dornier composite workshops. Advanced manufacturing technologies like true angle lay-up by CNC fibre placement and filament winding are utilized. The protected coating is applied at the CAHA facilities at the Calar Alto Observatory, Spain. The exhaustive environmental testing is performed at the facilities of IABG, Munich (mechanical testing) and for the cryo-optical tests at CSL Liege. The project is in advanced state with both Qualification Models being under environmental testing. The flight models will be delivered in 2004. The paper gives an overview over the requirements and the main structural features how these requirements are met. Special production aspects and available test results are reported.

  17. Comparing NEO Search Telescopes

    Myhrvold, Nathan

    2016-04-01

    Multiple terrestrial and space-based telescopes have been proposed for detecting and tracking near-Earth objects (NEOs). Detailed simulations of the search performance of these systems have used complex computer codes that are not widely available, which hinders accurate cross-comparison of the proposals and obscures whether they have consistent assumptions. Moreover, some proposed instruments would survey infrared (IR) bands, whereas others would operate in the visible band, and differences among asteroid thermal and visible-light models used in the simulations further complicate like-to-like comparisons. I use simple physical principles to estimate basic performance metrics for the ground-based Large Synoptic Survey Telescope and three space-based instruments—Sentinel, NEOCam, and a Cubesat constellation. The performance is measured against two different NEO distributions, the Bottke et al. distribution of general NEOs, and the Veres et al. distribution of Earth-impacting NEO. The results of the comparison show simplified relative performance metrics, including the expected number of NEOs visible in the search volumes and the initial detection rates expected for each system. Although these simplified comparisons do not capture all of the details, they give considerable insight into the physical factors limiting performance. Multiple asteroid thermal models are considered, including FRM, NEATM, and a new generalized form of FRM. I describe issues with how IR albedo and emissivity have been estimated in previous studies, which may render them inaccurate. A thermal model for tumbling asteroids is also developed and suggests that tumbling asteroids may be surprisingly difficult for IR telescopes to observe.

  18. Telescope Time Allocation Tool

    Alves, J.

    2005-03-01

    TaToo is ESO's new Time Allocation Tool. This software scheduler is a combination of a user-friendly graphical user interface and an intelligent constraint-programming engine fine-tuned to ESO's scheduling problem. TaToo is able to produce a high quality and reliable schedule taking into consideration all constraints of the recommended programs for all telescopes in about 15 minutes. This performance allows schedulers at ESO-VISAS to simulate and evaluate different scenarios, optimize the scheduling of engineering activities at the observatories, and in the end construct the most science efficient schedule possible.

  19. Reynolds Stress and Sheared Poloidal Flow in the Edge Plasma Region of the HT-6M Tokamak

    WANG Wen-Hao; YU Chang-Xuan; XU Yu-Hong; LING Bi-Li; GONG Xian-Zu; LIU Bao-Hua; WAN Bao-Nian

    2001-01-01

    High spatial resolution measurements of the electrostatic Reynolds stress, radial electric field and poloidal phase velocity of fluctuations in the edge region of the HT-6M tokamak are carried out. The Reynolds stress shows a radial gradient in proximity to the poloidal velocity shear. A comparison of the profiles between the Reynolds stress gradient and the poloidal velocity damping reveals some similarity in their magnitude and radial structure. These facts suggest that the turbulence-induced Reynolds stress may play a significant role in generating the poloidal flow in the plasma edge region.

  20. The Cherenkov Telescope Array

    Bigongiari, Ciro

    2016-01-01

    The Cherenkov Telescope Array (CTA) is planned to be the next generation ground based observatory for very high energy (VHE) gamma-ray astronomy. Gamma-rays provide a powerful insight into the non-thermal universe and hopefully a unique probe for new physics. Imaging Cherenkov telescopes have already discovered more than 170 VHE gamma-ray emitters providing plentiful of valuable data and clearly demonstrating the power of this technique. In spite of the impressive results there are indications that the known sources represent only the tip of the iceberg. A major step in sensitivity is needed to increase the number of detected sources, observe short time-scale variability and improve morphological studies of extended sources. An extended energy coverage is advisable to observe far-away extragalactic objects and improve spectral analysis. CTA aims to increase the sensitivity by an order of magnitude compared to current facilities, to extend the accessible gamma-ray energies from a few tens of GeV to a hundred o...

  1. Antares Reference Telescope System

    Viswanathan, V.K.; Kaprelian, E.; Swann, T.; Parker, J.; Wolfe, P.; Woodfin, G.; Knight, D.

    1983-01-01

    Antares is a 24-beam, 40-TW carbon-dioxide laser-fusion system currently nearing completion at the Los Alamos National Laboratory. The 24 beams will be focused onto a tiny target (typically 300 to 1000 ..mu..m in diameter) located approximately at the center of a 7.3-m-diameter by 9.3-m-long vacuum (10/sup -6/ torr) chamber. The design goal is to position the targets to within 10 ..mu..m of a selected nominal position, which may be anywhere within a fixed spherical region 1 cm in diameter. The Antares Reference Telescope System is intended to help achieve this goal for alignment and viewing of the various targets used in the laser system. The Antares Reference Telescope System consists of two similar electro-optical systems positioned in a near orthogonal manner in the target chamber area of the laser. Each of these consists of four subsystems: (1) a fixed 9X optical imaging subsystem which produces an image of the target at the vidicon; (2) a reticle projection subsystem which superimposes an image of the reticle pattern at the vidicon; (3) an adjustable front-lighting subsystem which illuminates the target; and (4) an adjustable back-lighting subsystem which also can be used to illuminate the target. The various optical, mechanical, and vidicon design considerations and trade-offs are discussed. The final system chosen (which is being built) and its current status are described in detail.

  2. Antares Reference Telescope System

    Antares is a 24-beam, 40-TW carbon-dioxide laser-fusion system currently nearing completion at the Los Alamos National Laboratory. The 24 beams will be focused onto a tiny target (typically 300 to 1000 μm in diameter) located approximately at the center of a 7.3-m-diameter by 9.3-m-long vacuum (10-6 torr) chamber. The design goal is to position the targets to within 10 μm of a selected nominal position, which may be anywhere within a fixed spherical region 1 cm in diameter. The Antares Reference Telescope System is intended to help achieve this goal for alignment and viewing of the various targets used in the laser system. The Antares Reference Telescope System consists of two similar electro-optical systems positioned in a near orthogonal manner in the target chamber area of the laser. Each of these consists of four subsystems: (1) a fixed 9X optical imaging subsystem which produces an image of the target at the vidicon; (2) a reticle projection subsystem which superimposes an image of the reticle pattern at the vidicon; (3) an adjustable front-lighting subsystem which illuminates the target; and (4) an adjustable back-lighting subsystem which also can be used to illuminate the target. The various optical, mechanical, and vidicon design considerations and trade-offs are discussed. The final system chosen (which is being built) and its current status are described in detail

  3. Upgrade of the MAGIC telescopes

    Mazin, Daniel; Garczarczyk, Markus; Giavitto, Gianluca; Sitarek, Julian

    2014-01-01

    The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. With 17m diameter mirror dishes and ultra-fast electronics, they provide an energy threshold as low as 50 GeV for observations at low zenith angles. The first MAGIC telescope was taken in operation in 2004 whereas the second one joined in 2009. In 2011 we started a major upgrade program to improve and to unify the stereoscopic system of the two similar but at that time different telescopes. Here we report on the upgrade of the readout electronics and digital trigger of the two telescopes, the upgrade of the camera of the MAGIC I telescope as well as the commissioning of the system after this major upgrade.

  4. An 11-bit 22-MS/s 0.6 mW SAR ADC with parasitic capacitance compensation

    This paper presents an 11-bit 22-MS/s 0.6-mW successive approximation register (SAR) analog-to-digital converter (ADC) using SMIC 65-nm low leakage (LL) CMOS technology with a 1.2 V supply voltage. To reduce the total capacitance and core area the split capacitor architecture is adopted. But in high resolution ADCs the parasitic capacitance in the LSB-side would decrease the linearity of the ADC and it is hard to calibrate. This paper proposes a parasitic capacitance compensation technique to cancel the effect with no calibration circuits. Moreover, dynamic circuits are used to minimize the switching power of the digital logic and also can reduce the latency time. The prototype chip realized an 11-bit SAR ADC fabricated in SMIC 65-nm CMOS technology with a core area of 300 × 200 μm2. It shows a sampling rate of 22 MS/s and low power dissipation of 0.6 mW at a 1.2 V supply voltage. At low input frequency the signal-to-noise-and-distortion ratio (SNDR) is 59.3 dB and the spurious-free dynamic range is 72.2 dB. The peak figure-of-merit is 36.4 fJ/conversion-step. (semiconductor integrated circuits)

  5. Formation of non-equilibrium structures in R6M5 steel under strong pulse beams action

    Formation of non-equilibrium structures in R6M5 steel surface layer in the supply state under irradiation by strong pulse beams (SPB) is examined. Cylindric samples with diameter 10 mm and height 15 mm of R6M5 fast-cutting steel with following content (weight %): 0.85% C, 0.4% Mn, 0.5% Si, 4.0 Cr; 2.1% V; 5.3% Mo, 6.0% W; 0.4% Ni, Fe (the rest) were examined. Irradiation by SPB was conducted on the 'TEMP' modified accelerator operating in a technological regime with carbon beams parameters: energy from 0.3 up o 0.4 MeV, beam density in an impulse from 20 to 250 A/cm2, pulse duration from 60 tp 100 ns. The beam consists of 70 % carbon ions and 30 % hydrogen ions. Phase identification and its structural phase analysis have been studied on the DRON-3 X-ray diffractometer of common assignment. Topography of metallographic specimen surface has been examined on the REM-200 scanning electron microscope. Doping elements redistribution and phases quantitative characteristics after SPB action were studied with help of the X-ray spectral microanalysis (XRSA) on the MS-46 Camebax microanalyzer. Character of doping elements redistribution in the alloy (XRSA data) show its appreciably redistribution, moreover in the melted zone the increased content of molybdenum, tungsten, vanadium is observing, and in the zone of thermal action its increase relatively to matrix values

  6. Expression of CC Chemokine Ligand 20 and CC Chemokine Receptor 6 mRNA in Patients with Psoriasis Vulgaris

    吴艳; 李家文

    2004-01-01

    Summary: In order to explore the possible role of CC chemokine ligand 20 (CCL20) and its receptor CC chemokine receptor 6 (CCR6) in the pathogenesis of psoriasis, the expression levels of mRNA of them in psoriatic lesions were investigated. The skin biopsies were collected from skin lesions in 35 cases of psoriasis vulgaris and 18 normal controls. RT-PCR was used to semi-quantitatively analyze the mRNA expression of CCL20 and CCR6 in the psoriatic lesions and the normal skin tissues.The results showed that the mRNA of CCL20 and CCR6 was present in every specimen. The expression levels of CCL20 mRNA in skin lesions were 1. 1397±0. 0521, which were greatly higher than those in normal controls (0.8681±0.0308) (P<0. 001). The expression levels of CCR6 mRNA in skin lesions were 1.1103±0.0538, significantly higher than in the controls (0.9131±0.0433, P<0. 001). These findings indicate that up-regulated expression of CCL20 and CCR6 mRNA might be related to the pathogenesis of psoriasis.

  7. Construction of a Schwarzschild-Couder telescope as a candidate for the Cherenkov Telescope Array: status of the optical system

    Rousselle, J; Cameron, R; Connaughton, V; Errando, M; Guarino, V; Humensky, T B; Jenke, P; Kieda, D; Mukherjee, R; Nieto, D; Okumura, A; Petrashyk, A; Vassiliev, V

    2015-01-01

    We present the design and the status of procurement of the optical system of the prototype Schwarzschild-Couder telescope (pSCT), for which construction is scheduled to begin in fall at the Fred Lawrence Whipple Observatory in southern Arizona, USA. The Schwarzschild-Couder telescope is a candidate for the medium-sized telescopes of the Cherenkov Telescope Array, which utilizes imaging atmospheric Cherenkov techniques to observe gamma rays in the energy range of 60Gev-60TeV. The pSCT novel aplanatic optical system is made of two segmented aspheric mirrors. The primary mirror has 48 mirror panels with an aperture of 9.6 m, while the secondary, made of 24 panels, has an diameter of 5.4 m. The resulting point spread function (PSF) is required to be better than 4 arcmin within a field of view of 6.4 degrees (80% of the field of view), which corresponds to a physical size of 6.4 mm on the focal plane. This goal represents a challenge for the inexpensive fabrication of aspheric mirror panels and for the precise ali...

  8. A medium sized telescope prototype for the Cherenkov Telescope Array

    The CTA (Cherenkov Telescope Array) is a proposed next generation instrument to observe very high energy (VHE) gamma-rays at ground level. The array will consist of 3 sizes of telescope covering a wide photon energy range: small (4m diameter) telescopes sensitive to the highest energy photons, medium sized telescopes (12 m) operating in the mid energy range, and a small number of large telescopes (24 m) with high sensitivity to low energy photons. Current Cherenkov Telescope experiments consist of up to 5 telescopes; CTA will be made up of an order of magnitude more, which will greatly enhance the number of photons that can be detected as well as increasing the number of views of each cascade, bringing significantly improved angular resolution and background suppression. The observatory is currently in the planning and development phase. A prototype CTA medium sized telescope (MST) is being built in Adlershof (Berlin). This talk focuses on plans for CTA and the design and construction of the MST prototype, as well as its operation, instrumentation and early measurement results.

  9. First measurements with a new 6m long violin-bow marine heat probe off Costa Rica

    Gennerich, H.-H.; Grevemeyer, I.; Heesemann, B.; Heesemann, M.; Kaul, N.; Müller, M.; Villinger, H.

    2003-04-01

    The design of a new 6m long violin-bow marine heat probe, first successful tests and data collected off Costa Rica during cruise M54-2 on RV METEOR in August 2002 are presented. The mechanically robust heat probe is designed for the operation in a pogo-style mode with a wide application range from 6000m deep sea trenches with mostly soft sediments to the upper continental slope where sediments are often sandy and difficult to penetrate. Due to the 6m length of its temperature sensor string undisturbed temperature gradients can be determined in shallow water with seasonal bottom water temperature variations. The heat probe is constructed in the classical "violin bow" design, with 22 thermistors equidistantly distributed inside an oil filled hydraulic tube attached to the strength member. The sensor tube also contains a heater wire for the generation of a calibrated heat pulse for in situ thermal conductivity measurements. The signal of the temperature sensors is measured with a resolution of 20-bits at a sample rate of 1 sec, resulting in a final temperature resolution of less than 1 mK at ambient sea floor temperatures. A carefully calibrated seawater sensor on top of the weight stand allows to measure the absolute bottom water temperature. Inclination and acceleration of the probe is measured also with a 1 sec sample rate to monitor the penetration process into the sediments and potential disturbances during the measurement period while the probe sits in the sediment. Data from a pressure sensor in conjunction with an acoustic altimeter allow the exact absolute measurement of the final penetration depth of the probe. The complete data set is stored in the probe but also transmitted via coax cable on board in real time which allows operational decisions during long term deployments of the probe. In addition the heat probe can be operated in a completely autonomous mode with internal storage and automated heat pulses. The battery capacity allows for 3 days

  10. The neutrino telescope ANTARES

    Gleixner Andreas

    2014-04-01

    Full Text Available The ANTARES neutrino telescope is currently the largest neutrino detector in the Northern Hemisphere. The detector consists of a three-dimensional array of 885 photomultiplier tubes, distributed along 12 lines, located at a depth of 2500 m in the Mediterranean Sea. The purpose of the experiment is the detection of high-energy cosmic neutrinos. The detection principle is based on the observation of Cherenkov-Light emitted by muons resulting from charged-current interactions of muon neutrinos in the vicinity of the detection volume. The main scientific targets of ANTARES include the search for astrophysical neutrino point sources, the measurement of the diffuse neutrino flux and the indirect search for dark matter.

  11. Spectroradiometry with Space Telescopes

    Pauluhn, Anuschka; Smith, Peter L; Colina, Luis

    2015-01-01

    Radiometry has been of fundamental importance in astronomy from the early beginnings. Initially, astronomers had their own radiometric system, based on extraterrestrial standards, namely the irradiance of stars expressed in visual magnitudes. Observing and comparing magnitudes in specific spectral bands then led to the astronomical spectrophotometry. The advent of astronomical high-resolution spectroscopy offered the possibility to interpret observations through physical models of stellar atmospheres. Such models had to be constructed based on physics-related units, and such units, rather than magnitudes, were then used for observational tests of the models. In this review, we provide an overview of how to achieve a valid laboratory calibration, and discuss ways to reliably extend this calibration to the spectroscopic telescope's performance in space. Recently, the quest for independent calibrations traceable to laboratory standards has become a well-supported aim, and has led to plans for now also launching ...

  12. The Travelling Telescope

    Owen, Daniel

    2015-08-01

    The telescope has been around for over 400 years, yet most people have never looked though one. We invite people outside under the stars to learn about those curious lights in the sky, and have a close encounter with the cosmos.Our main aim is to promote science, technology, engineering, and mathematics to the young minds by inspiring, empowering and engaging them using astronomy and astrophysics tools and concepts. We would like to see Africa compete with the rest of the world and we believe this can happen through having a scientifically literate society. We also work closely wit teachers, parents and the general public to further our objectives. We will present on our recently awarded project to work with schools in rural coastal Kenya, a very poor area of the country. We will also present on other work we continue to do with schools to make our project sustainable even after the OAD funding.

  13. The ANTARES neutrino telescope

    Zornoza, Juan de Dios

    2012-01-01

    The ANTARES collaboration completed the installation of the first neutrino detector in the sea in 2008. It consists of a three dimensional array of 885 photomultipliers to gather the Cherenkov photons induced by relativistic muons produced in charged-current interactions of high energy neutrinos close to/in the detector. The scientific scope of neutrino telescopes is very broad: the origin of cosmic rays, the origin of the TeV photons observed in many astrophysical sources or the nature of dark matter. The data collected up to now have allowed us to produce a rich output of physics results, including the map of the neutrino sky of the Southern hemisphere, search for correlations with GRBs, flaring sources, gravitational waves, limits on the flux produced by dark matter self-annihilations, etc. In this paper a review of these results is presented.

  14. Composite telescope technology

    Chen, Peter C.; Rabin, Douglas

    2014-07-01

    We report the development of optical mirrors based on polymer matrix composite materials. Advantages of this technology are low cost and versatility. By using appropriate combinations of polymers and various metallic and nonmetallic particles and fibers, the properties of the materials can be tailored to suit a wide variety of applications. We report the fabrication and testing of flat and curved mirrors made with metal powders, multiple mirrors replicated with high degree of uniformity from the same mandrels, cryogenic testing, mirrors made of ferromagnetic materials that can be actively or adaptively controlled by non-contact actuation, optics with very smooth surfaces made by replication, and by spincasting. We discuss development of a new generation of ultra-compact, low power active optics and 3D printing of athermal telescopes.

  15. Microoptical telescope compound eye.

    Duparré, Jacques; Schreiber, Peter; Matthes, André; Pshenay-Severin, Ekaterina; Bräuer, Andreas; Tünnermann, Andreas; Völkel, Reinhard; Eisner, Martin; Scharf, Toralf

    2005-02-01

    A new optical concept for compact digital image acquisition devices with large field of view is developed and proofed experimentally. Archetypes for the imaging system are compound eyes of small insects and the Gabor-Superlens. A paraxial 3x3 matrix formalism is used to describe the telescope arrangement of three microlens arrays with different pitch to find first order parameters of the imaging system. A 2mm thin imaging system with 21x3 channels, 70 masculinex10 masculine field of view and 4.5mm x 0.5mm image size is optimized and analyzed using sequential and non-sequential raytracing and fabricated by microoptics technology. Anamorphic lenses, where the parameters are a function of the considered optical channel, are used to achieve a homogeneous optical performance over the whole field of view. Captured images are presented and compared to simulation results. PMID:19494951

  16. 友善用脑教学法保持课堂动力的6M

    王精华

    2010-01-01

    本文归纳出友善用脑教学法保持课堂动力的6M,印:Music音乐--用来激发良好的身体/大脑状态;Movement运动--协调身体/大脑和缓减压力;Multisensory多感官教学--多样化的教学方式,激发学生思维;Mindmapping思维导图--更多的个人记忆参照物;Meditation冥想--另外一种使课堂融洽的放松和记忆方法;Mimmow("Making it memorable my own way") "以我自己的方式记忆".

  17. Perovskite LaPbMSbO6 (M=Co, Ni): Structural distortion, magnetic and dielectric properties

    The B-site ordered double perovskite oxides LaPbMSbO6 (M=Co, Ni) have been synthesized via the modified Sol–Gel precursor two-step route. Rietveld refinements reveal strong abnormal structural distortion and BO6 octahedral deformation appearing along the ab plane. Owing to the cooperative Jahn–Teller effect of Co2+ and Pb2+ ions, the Co-related compound exhibits almost complete Co2+–Sb5+ order. For magnetic properties, spin-canted antiferromagnetic state with high extent of magnetic frustration is confirmed. The Ni-related compound presents heavier magnetic frustration for introducing tiny disorder on site occupation accompanied with valence state and further enhancing the complexity of magnetic competition. Dielectric measurements present a considerable temperature dependent dielectric relaxation with great dc-like loss feature in the LaPbCoSbO6. For LaPbNiSbO6, however, the permittivity with low dielectric loss is shown to be insensitive to either temperature or frequency. The corresponding electronic active energy manifests that the weakly bounded 3d-electron is prone to hop in a more distorted Co–Sb sublattice. - Graphical abstract: XRD Rietveld refinement result of LaPbCoSbO6 presented a large BO6 octahedral distortion along the ab plane. Based upon the variations from Co–O–Sb bond angles, a fierce competition from many extended magnetic coupling routes (M–O–O–M) would induce a considerably large magnetic frustration and electron hopping restriction. - Highlights: • Highly ordered LaPbMSbO6 (M=Co, Ni) were synthesized. • Abnormal structural distortion appeared in the ab plane. • Strong magnetic frustration was confirmed via M2+–O–O–M2+ route. • Dielectric measurements presented a large difference between Co and Ni samples. • 3d-electronic structure determines lattice distortion and physical properties

  18. Building the Hubble Space Telescope

    The development of the design for the Hubble Space Telescope (HST) is discussed. The HST optical system is described and illustrated. The financial and policy issues related to the development of the HST are considered. The actual construction of the HST optical telescope is examined. Also, consideration is given to the plans for the HST launch

  19. GREGOR telescope: start of commissioning

    Volkmer, R.; von der Lühe, O.; Denker, C.; Solanki, S.K.; Balthasar, H.; Berkefeld, T.; Caligari, P.; Collados, M.; Halbgewachs, C.; Heidecke, F.; Hofmann, A.; Klvaňa, Miroslav; Kneer, F.; Lagg, A.; Popow, E.; Schmidt, D.; Schmidt, W.; Sobotka, Michal; Soltau, D.; Strassmeier, K.G.

    Bellingham: SPIE, 2010 - (Stepp, L.), 77330K-1-77330K-9. (Proceedings of SPIE. 7733). ISBN 9780819482235. [Ground-based and Airborne Telescopes III. San Diego (US), 27.06.2010-02.07.2010] Institutional research plan: CEZ:AV0Z10030501 Keywords : GREGOR telescope Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  20. Infrared up-conversion telescope

    2014-01-01

    There is presented to an up-conversion infrared telescope (110) arranged for imaging an associated scene (130), wherein the up-conversion infrared telescope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein a first optical...

  1. Telescoping phenomenon in pathological gambling

    Grant, Jon E; Odlaug, Brian Lawrence; Mooney, Marc E

    2012-01-01

    The course of pathological gambling (PG) in women has been described as having a later age of initiation but a shorter time to problematic gambling ("telescoped"). This study examined evidence for telescoping and its relationship with comorbidities. Seventy-one treatment-seeking individuals with PG...

  2. Schwarzschild-Couder Telescope for the Cherenkov Telescope Array

    Meagher, Kevin J.

    2014-01-01

    The Cherenkov Telescope Array (CTA) is the next major ground-based observatory for gamma-ray astronomy. With CTA gamma-ray sources will be studied in the very-high energy gamma-ray range of a few tens of GeV to 100 TeV with up to ten times better sensitivity than available with current generation instruments. We discuss the proposed US contribution to CTA that comprises imaging atmospheric Cherenkov telescope with Schwarzschild-Couder (SC) optics. Key features of the SC telescope are a wide f...

  3. On the capabilities of survey telescopes of moderate size

    Terebizh, V Yu

    2016-01-01

    To explore capabilities of moderate-size optical telescopes in surveys, the set of 9 new wide-field designs having apertures up to 1 m is considered. All but one systems have angular field of view in a range 3.5-10 degrees and flat focal surface; the field of the last system is 45 degrees in diameter at the 0.5 m aperture and spherical focal surface. The complete description of the optical layouts is given in the Appendix. Relations between the expected limiting magnitude, survey speed and exposure time allow to choose the system that is most suitable for a particular task of observations. In principle, a single wide-field telescope with the aperture of approximately 1 m can detect objects brighter than 22.5 magnitude over the entire hemisphere within one night, however, the reliability of acquired data can be significantly increased by using a hierarchic observational network comprised of telescopes with optimized parameters.

  4. Dutch Open Telescope: Status and Prospects

    Rutten, R. J.; Hammerschlag, R.H.; Bettonvil, F.C.M.

    2001-01-01

    The Dutch Open Telescope represents a new solar telescope concept. Being open rather than evacuated, it leads the way to large- aperture high resolution telescopes. It is now being installed on La Palma.

  5. SOFIA: Flying the Telescope

    Asher, Troy; Cumming, Steve

    2012-01-01

    The Stratospheric Observatory For Infrared Astronomy (SOFIA) is an international cooperative development and operations program between the United States National Aeronautics and Space Administration (NASA) and the German Space Agency, DLR (Deutsches Zentrum fuer Luft-und Raumfahrt). SOFIA is a 2.5 meter, optical/infrared/sub-millimeter telescope mounted in a Boeing model 747SP-21 aircraft and will be used for many basic astronomical observations performed at stratospheric altitudes. It will accommodate installation of different focal plane instruments with in-flight accessibility provided by investigators selected from the international science community. The Facility operational lifetime is planned to be greater than 20 years. This presentation will present the results of developmental testing of SOFIA, including analysis, envelope expansion and the first operational mission. It will describe a brief history of open cavities in flight, how NASA designed and tested SOFIAs cavity, as well as flight test results. It will focus on how the test team achieved key milestones by systematically and efficiently reducing the number of test points to only those absolutely necessary to achieve mission requirements, thereby meeting all requirements and saving the potential loss of program funding. Finally, it will showcase examples of the observatory in action and the first operational mission of the observatory, illustrating the usefulness of the system to the international scientific community. Lessons learned on how to whittle a mountain of test points into a manageable sum will be presented at the conclusion.

  6. Global Astrophysical Telescope System - GATS

    Polińska, M.; Kamiński, K.; Dimitrov, W.; Fagas, M.; Borczyk, W.; Kwiatkowski, T.; Baranowski, R.; Bartczak, P.; Schwarzenberg-Czerny, A.

    2014-02-01

    The Global Astronomical Telescope System is a project managed by the Astronomical Observatory Institute of Adam Mickiewicz University in Poznań (Poland) and it is primarily intended for stellar medium/high resolution spectroscopy. The system will be operating as a global network of robotic telescopes. The GATS consists of two telescopes: PST 1 in Poland (near Poznań) and PST 2 in the USA (Arizona). The GATS project is also intended to cooperate with the BRITE satellites and supplement their photometry with spectroscopic observations.

  7. Polarimetry with multiple mirror telescopes

    West, S. C.

    1986-01-01

    The polarizations of multiple mirror telescopes are calculated using Mueller calculus. It is found that the Multiple Mirror Telescope (MMT) produces a constant depolarization that is a function of wavelength and independent of sky position. The efficiency and crosstalk are modeled and experimentally verified. The two- and four-mirror new generation telescopes are found to produce sinusoidal depolarization for which an accurate interpretation of the incident Stokes vector requires inverse matrix calculations. Finally, the depolarization of f/1 paraboloids is calculated and found to be less than 0.1 percent at 3000 A.

  8. Analysis concepts for large telescope structures under earthquake load

    Koch, Franz

    1997-03-01

    The very large telescope (VLT) of ESO will be placed on Cerro Paranal in the Atacama desert in northern Chile. This site provides excellent conditions for astronomical observations. However, it is likely that important seismic activities occur. The telescope structure and its components have to resist the largest earthquakes expected during their lifetime. Therefore, design specifications and structural analyses have to take into account loads caused by such earthquakes. The present contribution shows some concepts and techniques in the assessment of earthquake resistant telescope design by the finite element method (FEM). After establishing the general design criteria and the geological and geotechnical characteristics of the site location, the seismic action can be defined. A description of various representations of the seismic action and the procedure to define the commonly used response spectrum are presented in more detail. A brief description of the response spectrum analysis method and of the result evaluation procedure follows. Additionally, some calculation concepts for parts of the entire telescope structure under seismic loads are provided. Finally, a response spectrum analysis of the entire VLT structure performed at ESO is presented to show a practical application of the analysis method and evaluation procedure mentioned above.

  9. Bhavnagar Telescope: the most widely travelled telescope in the country

    Rao, N Kameswara; Vagiswari, A

    2014-01-01

    In the last decade of the 19th century Maharaja Takhtasingji Observatory was built at Poona (1888-1912) under the supervision of K.D.Naegamavala, with the grant from Maharaja of Bhavnagar (from where the name Bhavnagar Telescope must have originated. The story of this telescope from its inception to the current status is traced. IIA Archives has been extensively used to resource information for this note.

  10. The small size telescope projects for the Cherenkov Telescope Array

    ,

    2015-01-01

    The small size telescopes (SSTs), spread over an area of several square km, dominate the CTA sensitivity in the photon energy range from a few TeV to over 100 TeV, enabling for the detailed exploration of the very high energy gamma-ray sky. The proposed telescopes are innovative designs providing a wide field of view. Two of them, the ASTRI (Astrophysics con Specchi a Tecnologia Replicante Italiana) and the GCT (Gamma-ray Cherenkov Telescope) telescopes, are based on dual mirror Schwarzschild-Couder optics, with primary mirror diameters of 4 m. The third, SST-1M, is a Davies-Cotton design with a 4 m diameter mirror. Progress with the construction and testing of prototypes of these telescopes is presented. The SST cameras use silicon photomultipliers, with preamplifier and readout/trigger electronics designed to optimize the performance of these sensors for (atmospheric) Cherenkov light. The status of the camera developments is discussed. The SST sub-array will consist of about 70 telescopes at the CTA souther...

  11. Structural stability and electronic properties of Ba2MIrO6 (M = La, Y) by first principles

    We investigate the structural stability and electronic properties of ordered perovskite-type compounds Ba2MIrO6 (M = La, Y) by use of density functional theory. Cubic (Fm-3m), rhombohedral (R-3) and monoclinic (P21/n) phases are considered for each compound. It was found that the most energetically stable phase for Ba2YIrO6 and Ba2LaIrO6 is P21/n and R-3, respectively. It is also interesting to find that Ba2YIrO6 in R-3 phase, which was not reported in experiment, has a slightly lower energy than experimentally observed cubic Fm-3m phase. The calculated results also show that Ba2YIrO6 in Fm-3m, R-3 and P21/n phases and Ba2LaIrO6 in Fm-3m phase are half metallic, while Ba2LaIrO6 in R-3 and P21/n phases show semiconducting behavior. The calculated spin magnetic moments indicate that the pentavalent iridium ion has a low spin configuration (t2g4) both in Ba2YIrO6 and Ba2LaIrO6

  12. The Hopkins Ultraviolet Telescope: The Final Archive

    Dixon, William V.; Blair, William P.; Kruk, Jeffrey W.; Romelfanger, Mary L.

    2013-01-01

    The Hopkins Ultraviolet Telescope (HUT) was a 0.9 m telescope and moderate-resolution (Delta)lambda equals 3 A) far-ultraviolet (820-1850 Å) spectrograph that flew twice on the space shuttle, in 1990 December (Astro-1, STS-35) and 1995 March (Astro-2, STS-67). The resulting spectra were originally archived in a nonstandard format that lacked important descriptive metadata. To increase their utility, we have modified the original datareduction software to produce a new and more user-friendly data product, a time-tagged photon list similar in format to the Intermediate Data Files (IDFs) produced by the Far Ultraviolet Spectroscopic Explorer calibration pipeline. We have transferred all relevant pointing and instrument-status information from locally-archived science and engineering databases into new FITS header keywords for each data set. Using this new pipeline, we have reprocessed the entire HUT archive from both missions, producing a new set of calibrated spectral products in a modern FITS format that is fully compliant with Virtual Observatory requirements. For each exposure, we have generated quicklook plots of the fully-calibrated spectrum and associated pointing history information. Finally, we have retrieved from our archives HUT TV guider images, which provide information on aperture positioning relative to guide stars, and converted them into FITS-format image files. All of these new data products are available in the new HUT section of the Mikulski Archive for Space Telescopes (MAST), along with historical and reference documents from both missions. In this article, we document the improved data-processing steps applied to the data and show examples of the new data products.

  13. Lightweighted ZERODUR for telescopes

    Westerhoff, T.; Davis, M.; Hartmann, P.; Hull, T.; Jedamzik, R.

    2014-07-01

    The glass ceramic ZERODUR® from SCHOTT has an excellent reputation as mirror blank material for earthbound and space telescope applications. It is known for its extremely low coefficient of thermal expansion (CTE) at room temperature and its excellent CTE homogeneity. Recent improvements in CNC machining at SCHOTT allow achieving extremely light weighted substrates up to 90% incorporating very thin ribs and face sheets. In 2012 new ZERODUR® grades EXPANSION CLASS 0 SPECIAL and EXTREME have been released that offer the tightest CTE grades ever. With ZERODUR® TAILORED it is even possible to offer ZERODUR® optimized for customer application temperature profiles. In 2013 SCHOTT started the development of a new dilatometer setup with the target to drive the industrial standard of high accuracy thermal expansion metrology to its limit. In recent years SCHOTT published several paper on improved bending strength of ZERODUR® and lifetime evaluation based on threshold values derived from 3 parameter Weibull distribution fitted to a multitude of stress data. ZERODUR® has been and is still being successfully used as mirror substrates for a large number of space missions. ZERODUR® was used for the secondary mirror in HST and for the Wolter mirrors in CHANDRA without any reported degradation of the optical image quality during the lifetime of the missions. Some years ago early studies on the compaction effects of electron radiation on ZERODUR® were re analyzed. Using a more relevant physical model based on a simplified bimetallic equation the expected deformation of samples exposed in laboratory and space could be predicted in a much more accurate way. The relevant ingredients for light weighted mirror substrates are discussed in this paper: substrate material with excellent homogeneity in its properties, sufficient bending strengths, space radiation hardness and CNC machining capabilities.

  14. The AMiBA Hexapod Telescope Mount

    Koch, Patrick M.; Kesteven, Michael; Nishioka, Hiroaki; Jiang, Homin; Lin, Kai-Yang; Umetsu, Keiichi; Huang, Yau-De; Raffin, Philippe; Chen, Ke-Jung; Ibañez-Romano, Fabiola; Chereau, Guillaume; Huang, Chih-Wei Locutus; Chen, Ming-Tang; Ho, Paul T. P.; Pausch, Konrad; Willmeroth, Klaus; Altamirano, Pablo; Chang, Chia-Hao; Chang, Shu-Hao; Chang, Su-Wei; Han, Chih-Chiang; Kubo, Derek; Li, Chao-Te; Liao, Yu-Wei; Liu, Guo-Chin; Martin-Cocher, Pierre; Oshiro, Peter; Wang, Fu-Cheng; Wei, Ta-Shun; Wu, Jiun-Huei Proty; Birkinshaw, Mark; Chiueh, Tzihong; Lancaster, Katy; Lo, Kwok Yung; Martin, Robert N.; Molnar, Sandor M.; Patt, Ferdinand; Romeo, Bob

    2009-04-01

    The Array for Microwave Background Anisotropy (AMiBA) is the largest hexapod astronomical telescope in current operation. We present a description of this novel hexapod mount with its main mechanical components—the support cone, universal joints, jack screws, and platform—and outline the control system with the pointing model and the operating modes that are supported. The AMiBA hexapod mount performance is verified based on optical pointing tests and platform photogrammetry measurements. The photogrammetry results show that the deformations in the inner part of the platform are less than 120 μm rms. This is negligible for optical pointing corrections, radio alignment, and radio phase errors for the currently operational seven-element compact configuration. The optical pointing error in azimuth and elevation is successively reduced by a series of corrections to about 0farcm 4 rms which meets our goal for the seven-element target specifications.

  15. The AMiBA Hexapod Telescope Mount

    Koch, Patrick M; Nishioka, Hiroaki; Jiang, Homin; Lin, Kai-Yang; Umetsu, Keiichi; Huang, Yau-De; Raffin, Philippe; Chen, Ke-Jung; Ibanez-Romano, Fabiola; Chereau, Guillaume; Chen, Ming-Tang; Ho, Paul T P; Pausch, Konrad; Willmeroth, Klaus; Altamirano, Pablo; Chang, Chia-Hao; Chang, Shu-Hao; Chang, Su-Wei; Han, Chih-Chiang; Kubo, Derek; Li, Chao-Te; Liu, Guo-Chin; Martin-Cocher, Pierre; Oshiro, Peter; Wei, Ta-Shun; Birkinshaw, Mark; Lancaster, Katy; Lo, Kwok Yung; Martin, Robert N; Molnar, Sandor M; Patt, Ferdinand; Romeo, Bob

    2009-01-01

    AMiBA is the largest hexapod astronomical telescope in current operation. We present a description of this novel hexapod mount with its main mechanical components -- the support cone, universal joints, jack screws, and platform -- and outline the control system with the pointing model and the operating modes that are supported. The AMiBA hexapod mount performance is verified based on optical pointing tests and platform photogrammetry measurements. The photogrammetry results show that the deformations in the inner part of the platform are less than 120 micron rms. This is negligible for optical pointing corrections, radio alignment and radio phase errors for the currently operational 7-element compact configuration. The optical pointing error in azimuth and elevation is successively reduced by a series of corrections to about 0.4 arcmin rms which meets our goal for the 7-element target specifications.

  16. Hartung's Astronomical Objects for Southern Telescopes

    Malin, David; Frew, David J.

    1995-10-01

    Many of the most spectacular astronomical objects are found in the southern skies. With this up-to-date, superbly illustrated handbook, both the amateur with binoculars and the expert with a telescope can make discoveries about new and interesting objects. Professor E. J. Hartung first produced his comprehensive and highly respected guide in 1968. Now the book has been greatly expanded and thoroughly revised, enhancing its character as an indispensable information source. With over 150 illustrations, new material is included on constellations and celestial coordinate systems as well as more modern descriptions of stars, nebulae and galaxies. The authors have included a new "southern Messier" list of objects. The authors' passion for their subject make this a unique and inspirational book. Many of the beautiful photographs were taken by David Malin, the world's leading astronomical photographer. The result will fascinate active and armchair astronomers alike.

  17. The Hopkins Ultraviolet Telescope: The Final Archive

    Dixon, William V; Kruk, Jeffrey W; Romelfanger, Mary L

    2013-01-01

    The Hopkins Ultraviolet Telescope (HUT) was a 0.9 m telescope and moderate-resolution (~3 A) far-ultraviolet (820-1850 A) spectrograph that flew twice on the space shuttle, in 1990 December (Astro-1, STS-35) and 1995 March (Astro-2, STS-67). The resulting spectra were originally archived in a non-standard format that lacked important descriptive metadata. To increase their utility, we have modified the original data-reduction software to produce a new and more user-friendly data product, a time-tagged photon list similar in format to the Intermediate Data Files (IDFs) produced by the {\\it Far Ultraviolet Spectroscopic Explorer} calibration pipeline. We have transferred all relevant pointing and instrument-status information from locally-archived science and engineering databases into new FITS header keywords for each data set. Using this new pipeline, we have reprocessed the entire HUT archive from both missions, producing a new set of calibrated spectral products in a modern FITS format that is fully complia...

  18. Telescopic arm with automatic advance

    By means of the telescopic arm TV cameras, tools or the like can be moved in and out of reactor pressure vessels. For pressure and traction driving element a curved steel band is used which is guided in the central axis of the telescopic arm by means of one adapting element each per telescopic member. On advancing the steel band, which can absorb considerable bending moments, is drawn out of a cartridge with a spool, by meanes of friction rollers. A nozzle-shaped device in front of the cartridge is flattering the steel band before winding it up. The free buckling length of the stell band is never greater than the distance between two adapting elements (part in the shape of a parallelpiped with a slot for guiding the steel band) resp. the length of a telescopic member. (UWI)

  19. The Chinese Giant Solar Telescope

    Liu, Zhong; Deng, Yuanyong; Ji, Haisheng

    2014-01-01

    Chinese Giant Solar Telescope is the next generation ground-based solar telescope. The main science task of this telescope is to observe the ultra fine structures of the solar magnetic field and dynamic field. Due to the advantages in polarization detection and thermal controlling with a symmetrical circular system, the current design of CGST is a 6~8 meter circular symmetrical telescope. The results of simulations and analysis showed that the current design could meet the demands of most science cases not only in infrared bands but also in near infrared bands and even in visible bands. The prominences and the filaments are very important science cases of CGST. The special technologies for prominence observation will be developed, including the day time laser guide star and MCAO. CGST is proposed by all solar observatories and several institutes and universities in China. It is supported by CAS and NSFC (National Natural Science Foundation of China) as a long term astronomical project.

  20. Future High Energy Neutrino Telescopes

    Spiering, C

    2000-01-01

    This talk summarizes the main physics goals and basic methods of telescopes for high energy neutrinos. It reviews the present status of deep underwater telescopes and sketches the ICECUBE project as an example for a cube kilometer detector. It is suggested to develop techniques for radio and acoustic detection hand in hand with big optical arrays. These large arrays should be complemented by medium-size detectors in the Megaton range.

  1. The Submillimeter Telescope (SMT) project

    To exploit the potential of submillimeter astronomy, the Submillimeter Telescope (SMT) will be located at an altitude of 3178 meters on Emerald Peak 75 miles northeast of Tucson in Southern Arizona. The instrument is an altazimuth mounted f/13.8 Cassegrain homology telescope with two Nasmyth and bent Cassegrain foci. It will have diffraction limited performance at a wavelength of 300 microns and an operating overall figure accuracy of 15 microns rms. An important feature of the SMT is the construction of the primary and secondary reflectors out of aluminum-core CFRP face sheet sandwich panels, and the reflector backup structure and secondary support out of CFRP structural elements. This modern technology provides both a means for reaching the required precision of the SMT for both night and day operation (basically because of the low coefficient of thermal expansion and high strength-to-weight ratio of CFRP) and a potential route for the realization of lightweight telescopes of even greater accuracy in the future. The SMT will be the highest accuracy radio telescope ever built (at least a factor of 2 more accurate than existing telescopes). In addition, the SMT will be the first 10 m-class submillimeter telescope with a surface designed for efficient measurements at the important 350 microns wavelength atmospheric window. 9 refs

  2. The upgraded MAGIC Cherenkov telescopes

    Tescaro, D., E-mail: dtescaro@iac.es [Instituto de Astrofísica de Canarias (IAC), E-38205 La Laguna, Tenerife (Spain); Universidad de La Laguna (ULL), Dept. Astrofísica, E-38206 La Laguna, Tenerife (Spain)

    2014-12-01

    The MAGIC Cherenkov telescopes underwent a major upgrade in 2011 and 2012. A new 1039-pixel camera and a larger area digital trigger system were installed in MAGIC-I, making it essentially identical to the newer MAGIC-II telescope. The readout systems of both telescopes were also upgraded, with fully programmable receiver boards and DRS4-chip-based digitization systems. The upgrade eased the operation and maintenance of the telescopes and also improved significantly their performance. The system has now an integral sensitivity as good as 0.6% of the Crab Nebula flux (for E>400GeV), with an effective analysis threshold at 70 GeV. This allows MAGIC to secure one of the leading roles among the current major ground-based Imaging Atmospheric Cherenkov telescopes for the next 5–10 years. - Highlights: • In 2011 and 2012 the MAGIC telescopes underwent a two-stage major upgrade. • The new camera of MAGIC-I allows us to exploit a 1.4 larger trigger area. • The novel DRS4-based readout systems allow a cost-effective ultra-fast digitization. • The upgrade greatly improved the maintainability of the system. • MAGIC has now an optimal integral sensitivity of 0.6% of the Crab Nebula flux.

  3. The upgraded MAGIC Cherenkov telescopes

    The MAGIC Cherenkov telescopes underwent a major upgrade in 2011 and 2012. A new 1039-pixel camera and a larger area digital trigger system were installed in MAGIC-I, making it essentially identical to the newer MAGIC-II telescope. The readout systems of both telescopes were also upgraded, with fully programmable receiver boards and DRS4-chip-based digitization systems. The upgrade eased the operation and maintenance of the telescopes and also improved significantly their performance. The system has now an integral sensitivity as good as 0.6% of the Crab Nebula flux (for E>400GeV), with an effective analysis threshold at 70 GeV. This allows MAGIC to secure one of the leading roles among the current major ground-based Imaging Atmospheric Cherenkov telescopes for the next 5–10 years. - Highlights: • In 2011 and 2012 the MAGIC telescopes underwent a two-stage major upgrade. • The new camera of MAGIC-I allows us to exploit a 1.4 larger trigger area. • The novel DRS4-based readout systems allow a cost-effective ultra-fast digitization. • The upgrade greatly improved the maintainability of the system. • MAGIC has now an optimal integral sensitivity of 0.6% of the Crab Nebula flux

  4. Experimental and theoretical characterization of acoustic noise from a 7.6 m diameter yaw controlled teetered rotor wind turbine

    Moroz, E. [Univ. of Texas at El Paso, Dept. of Mechanical and Industrial Engineering, El Paso, TX (United States)

    1997-12-31

    An experimental investigation into the acoustic noise from a small (7.6 m diameter) teetered rotor wind turbine, set at various yaw angles up to 90 degrees of yaw, was conducted. The results revealed a 1/3 octave spectra which was dominated by a broad peak in the higher frequency range, at all yaw angles investigated. This prompted a theoretical investigation to reveal the mechanisms producing the dominant feature in the experimentally obtained noise spectra and resulted in the development of a wind turbine aerodynamic noise prediction coce, WTNOISE. The location near busy roads and the relatively rough terrain of the wind test site caused difficulties in obtaining useful noise spectral information below 500Hz. However, sufficiently good data was obtained above 500Hz to clearly show a dominant `hump` in the spectrum, centered between 3000 and 4000Hz. Although the local Reynolds number for the blade elements was around 500,000 and one might expect Laminar flow over a significant portion of the blade, the data did not match the noise spectra predicted when Laminar flow was assumed. Given the relatively poor surface quality of the rotor blades and the high turbulence of the test site it was therefore assumed that the boundary layer on the blade may have tripped relatively early and that the turbulent flow setting should be used. This assumption led to a much better correlation between experiment and predictions. The WTNOISE code indicated that the broad peak in the spectrum was most likely caused by trailing edge bluntness noise. Unfortunately time did not allow for modifications to the trailing edge to be investigated. (au)

  5. SOFIA: Flying the Telescope

    Asher, Troy A.; Cumming, Stephen B.

    2012-01-01

    and a proof of concept mission for which SOFIA was opportunely positioned is showcased. Success on this time-critical mission to observe a rare astronomical event proved the usefulness of an airborne observatory and the value in waiting for the capability provided by SOFIA. Finally, lessons learned in the test program are presented with emphasis on how lessons from previous aircraft and successful test programs were applied to SOFIA. Effective application of these lessons was crucial to the success of the SOFIA flight test program. SOFIA is an international cooperative program between NASA and the German Space Agency, DLR. It is a 2.5 meter (100-inch) telescope mounted in a Boeing 747SP aircraft used for astronomical observations at altitudes above 35,000 feet. SOFIA will accommodate a host of scientific instruments from the international science community and has a planned operational lifespan of more than 20 years.

  6. The Research Productivity of Small Telescopes and Space Telescopes

    Ringwald, F A; Lovell, R L; Kays, S A; Torres, Y V A

    2003-01-01

    We present statistics on the research productivity of astronomical telescopes. These were compiled by finding papers in which new data were presented, noting which telescopes were used, and then counting the number of papers, number of pages, and other statistics. The journals used were the Astronomical Journal, the Astrophysical Journal (including the Letters and Supplements), and the Publications of the Astronomical Society of the Pacific. We also compiled citations from the Science Citation Index. This work was designed to be similar to that of Trimble (1995), except that more recent journals (from 1995) and citations (from 1998) were used. We also did not restrict our sample to large telescopes only: we included all telescopes from which new data were presented, the smallest of which was a 0.1-m. The data were gathered by first-year work-study undergraduates, who were instructed to include data for all telescopes for which they found new data were included in the journals. A by-product of this research wa...

  7. Alignment and phasing of deployable telescopes

    Woolf, N. J.; Ulich, B. L.

    1983-01-01

    The experiences in coaligning and phasing the Multi-Mirror Telescope (MMT), together with studies in setting up radio telescopes, are presented. These experiences are discussed, and on the basis they furnish, schemes are suggested for coaligning and phasing four large future telescopes with complex primary mirror systems. These telescopes are MT2, a 15-m-equivalent MMT, the University of California Ten Meter Telescope, the 10 m sub-mm wave telescope of the University of Arizona and the Max Planck Institute for Radioastronomy, and the Large Deployable Reflector, a future space telescope for far-IR and sub-mm waves.

  8. The Search for Optical and NIR Counterparts of GRBs with the Super-LOTIS Telescope

    Williams, G. G.; Park, H. S.; Barthelmy, S.; Hartmann, D.; Lindsay, K.; Bradshaw, M.

    2003-05-01

    The 0.6-m Super-LOTIS (Livermore Optical Transient Imaging System) telescope is a fully robotic system dedicated to the search for prompt optical emission from gamma-ray bursts. The telescope began routine operations from its Steward Observatory site atop Kitt Peak in April 2000. An overview of its predecessors, the GROCSE and LOTIS telescopes, will be presented. We will summarize the current capabilities of the system and present recent scientific results. A progress report will be given on the upgrade of the system to allow for simultaneous near-infrared and optical imaging. This upgrade will be completed to coincide with the launch of the Swift GRB explorer mission in late fall 2003.

  9. Space Telescope maintenance and refurbishment

    Trucks, H. F.

    1983-01-01

    The Space Telescope (ST) represents a new concept regarding spaceborne astronomical observatories. Maintenance crews will be brought to the orbital worksite to make repairs and replace scientific instruments. For major overhauls the telescope can be temporarily returned to earth with the aid of the Shuttle. It will, thus, be possible to conduct astronomical studies with the ST for two decades or more. The five first-generation scientific instruments used with the ST include a wide field/planetary camera, a faint object camera, a faint object spectrograph, a high resolution spectrograph, and a high speed photometer. Attention is given to the optical telescope assembly, the support systems module, aspects of mission and science operations, unscheduled maintenance, contingency orbital maintenance, planned on-orbit maintenance, ground maintenance, ground refurbishment, and ground logistics.

  10. FAMOUS. The fluorescence telescope prototype

    Schumacher, Johannes; Bretz, Thomas; Hebbeker, Thomas; Lauscher, Markus; Middendorf, Lukas; Niggemann, Tim; Peters, Christine; Sommer, Dominik; Stephan, Maurice [III. Physikalisches Institut A, RWTH Aachen University (Germany); Auffenberg, Jan; Schaufel, Merlin [III. Physikalisches Institut B, RWTH Aachen University (Germany)

    2015-07-01

    One of the most successful techniques for the detection of air showers produced by ultra-high-energy cosmic rays are fluorescence telescopes. The light produced by de-exciting nitrogen in the atmosphere is typically detected by photomultiplier tubes (PMTs). This technique has been successfully used by the Pierre Auger Observatory in Argentina for many years. Silicon photomultipliers (SiPMs) promise higher photon detection efficiencies than PMTs. This and other advantages motivate the construction of the fluorescence telescope prototype FAMOUS (First Auger Multi-pixel photon counter camera for the Observation of Ultra-high-energy air Showers) which makes use of SiPMs. In this talk we discuss the FAMOUS telescope with a new 64-pixel camera including power supply and DAQ.

  11. FAMOUS. The fluorescence telescope prototype

    One of the most successful techniques for the detection of air showers produced by ultra-high-energy cosmic rays are fluorescence telescopes. The light produced by de-exciting nitrogen in the atmosphere is typically detected by photomultiplier tubes (PMTs). This technique has been successfully used by the Pierre Auger Observatory in Argentina for many years. Silicon photomultipliers (SiPMs) promise higher photon detection efficiencies than PMTs. This and other advantages motivate the construction of the fluorescence telescope prototype FAMOUS (First Auger Multi-pixel photon counter camera for the Observation of Ultra-high-energy air Showers) which makes use of SiPMs. In this talk we discuss the FAMOUS telescope with a new 64-pixel camera including power supply and DAQ.

  12. Quantum telescope: feasibility and constraints.

    Kurek, A R; Pięta, T; Stebel, T; Pollo, A; Popowicz, A

    2016-03-15

    The quantum telescope is a recent idea aimed at beating the diffraction limit of spaceborne telescopes and possibly other distant target imaging systems. There is no agreement yet on the best setup of such devices, but some configurations have already been proposed. In this Letter we characterize the predicted performance of quantum telescopes and their possible limitations. Our extensive simulations confirm that the presented model of such instruments is feasible and the device can provide considerable gains in the angular resolution of imaging in the UV, optical, and infrared bands. We argue that it is generally possible to construct and manufacture such instruments using the latest or soon to be available technology. We refer to the latest literature to discuss the feasibility of the proposed QT system design. PMID:26977642

  13. Scientific management of Space Telescope

    Odell, C. R.

    1981-01-01

    A historical summay is given on the science management of the Space Telescope, the inception of which began in 1962, when scientists and engineers first recommended the development of a nearly diffraction limited substantial-size optical telescope. Phase A, the feasibility requirements generation phase, began in 1971 and consisted largely of NASA scientists and a NASA design. Phase B, the preliminary design phase, established a tiered structure of scientists, led by the Large Space Telescope operations and Management Work Group. A Mission Operations Working Group headed six instrument definition teams to develop the essential instrument definitions. Many changes took place during Phase B, before design and development, which began in 1978 and still continues today.

  14. Construction of prototype two-mirror Schwartzchild-Couder Imaging Air Cherenkov Telescope (IACT) for VHE gamma-ray astronomy

    Kieda, David; CTA-US Collaboration Collaboration

    2016-03-01

    Next generation ground-based VHE gamma-ray observatories such as the Cherenkov Telescope Array (CTA) will employ an array of different sized IACTs distributed across square kilometer areas. During 2015-2016, the CTA-US collaboration is constructing a prototype 9.6 m primary diameter Schwartzchild-Couder IACT (SCT) at the FL Whipple Observatory, Amado, AZ USA. The two-mirror SCT design provides 8 degree field of view with 0.067 degree pixel size. The SCT uses a high resolution (11,328 pixel) Silicon PhotoMultiplier (SiPM) camera to record atmospheric Cherenkov light images generated by gamma-ray and cosmic ray primaries. Incorporation of SCT telescopes into a CTA-type observatory can provide superior angular resolution (30 % improvement) and point source sensitivity (30-50 %). In this talk, I will describe the capabilities of the SCT telescope, and the construction and commissioning of the prototype SCT telescope during 2016.

  15. Apollo Telescope Mount Spar Assembly

    1969-01-01

    The Apollo Telescope Mount (ATM), designed and developed by the Marshall Space Flight Center, served as the primary scientific instrument unit aboard the Skylab. The ATM contained eight complex astronomical instruments designed to observe the Sun over a wide spectrum from visible light to x-rays. This image shows the ATM spar assembly. All solar telescopes, the fine Sun sensors, and some auxiliary systems are mounted on the spar, a cruciform lightweight perforated metal mounting panel that divides the 10-foot long canister lengthwise into four equal compartments. The spar assembly was nested inside a cylindrical canister that fit into the rack, a complex frame, and was protected by the solar shield.

  16. Wide field of view telescope

    Ackermann, Mark R.; McGraw, John T.; Zimmer, Peter C.

    2008-01-15

    A wide field of view telescope having two concave and two convex reflective surfaces, each with an aspheric surface contour, has a flat focal plane array. Each of the primary, secondary, tertiary, and quaternary reflective surfaces are rotationally symmetric about the optical axis. The combination of the reflective surfaces results in a wide field of view in the range of approximately 3.8.degree. to approximately 6.5.degree.. The length of the telescope along the optical axis is approximately equal to or less than the diameter of the largest of the reflective surfaces.

  17. Telescope sipping impact refuelling outages

    Based on world wide leading technology in fuel leak detection ABB Nuclear Services developed a new sipping method for Boiling Water Reactors during early nineties, the so called ''TELESCOPE sipping''. The method is today recognised as a reliable and the fastest sipping method and has been used in six BWR sipping projects, where the fuel bundles in the reactor core were tested and all leaking fuel assemblies were identified. Today the TELESCOPE sipping method is also developed for Pressurized Water Reactors as an improvement or replacement alternative of the so called ''INMAST sipping'' method. Patents are pending for both applications. (Author). 3 figs

  18. LISA telescope spacer design investigations

    Sanjuan, Josep; Mueller, Guido; Livas, Jeffrey; Preston, Alix; Arsenovic, Petar; Castellucci, Kevin; Generie, Joseph; Howard, Joseph; Stebbins, Robin

    The Laser Interferometer Space Antenna (LISA) is a space-based gravitational wave observa-tory with the goal of observing Gravitational Waves (GWs) from astronomical sources in a frequency range from 30 µHz to 0.1 Hz. The detection of GWs at such low frequency requires measurements of distances at the pico-meter level between bodies separated by 5 million kilo-meters. The LISA mission consists of three identical spacecraft (SC) separated by 5 × 106 km forming an equilateral triangle. Each SC contains two optical assemblies and two vacuum en-closures housing one proof mass (PM) in geodesic (free fall) motion each. The two assemblies on one SC are each pointing towards an identical assembly on each of the other two SC to form a non-equal arm interferometer. The measurement of the GW strain is done by measuring the change in the length of the optical path between the PMs of one arm relative to the other arms caused by the pass of a GW. An important element of the Interferometric Measurement System (IMS) is the telescope which, on one hand, gathers the light coming from the far SC (˜100 pW) and, on the other hand, expands and collimates the small outgoing beam ( 1 W) and sends it to the far SC. Due to the very demanding sensitivity requirements care must be taken in the design and validation of the telescope not to degrade the IMS performance. For instance, the diameter of the telescope sets the the shot noise of the IMS and depends critically on the diameter of the primary and the divergence angle of the outgoing beam. As the telescope is rather fast telescope, the divergence angle is a critical function of the overall separation between the primary and secondary. Any long term changes of the distance of more than a a few micro-meter would be detrimental to the LISA mission. Similarly challenging are the requirements on the in-band path-length noise for the telescope which has to be kept below 1 pm Hz-1/2 in the LISA band. Different configurations (on-axis/off axis

  19. Technology development for cryogenic deployable telescope structures and mechanisms

    Atkinson, Charles B.; Gilman, Larry; Reynolds, Paul

    2003-12-01

    At 6-7 meters in diameter, the James Webb Space Telescope (JWST) will require structures that remain stable to levels that are on the order of 10 nanometers under dynamic and thermal loading while operating at cryogenic temperatures. Moreover, the JWST will be the first telescope in space that is deployed, resulting in an aperture that is not only segmented, but has hinge-lines and the associated joining systems or latches in it. In order to understand the behavior and reduce the risk associated with very large, deployed structures and the stability of the associated structure and latches, we developed and tested the largest cryogenic structure ever built and then characterized its stability. This paper presents a description of the design of the Development Optical Telescope Assembly (DOTA), the testing performed, and the results of the testing performed on it. We discuss the material selection and characterization processes, give a description of the test configurations, describe the metrology equipment and the validation process for it, provide the test results, and summarize the conclusions drawn from the results. The testing and associated results include characterization of the thermal stability of the large-scale structure, characterization of the micro-dynamic stability of the latching system, and measurements of the deployment capability of the mechanisms. We also describe how the DOTA design relates to the JWST design and how the test results relate to the JWST requirements.

  20. Direct Detection 1.6?m DIAL / Doppler Lidar for Measurements of CO2 Concentration and Wind Profiles (Invited)

    Shibata, Y.; Nagasawa, C.; Abo, M.

    2013-12-01

    Knowledge of present carbon sources and sinks including their spatial distribution and their variation in time is one of the essential information for predicting future CO2 atmospheric concentration levels. Moreover, wind information is an important parameter for transport simulations and inverse estimation of surface CO2 flux. The differential absorption lidar (DIAL) and the Doppler wind lidar with the range resolution is expected to measure atmospheric CO2 profiles and wind profiles in the atmospheric boundary layer and lower troposphere from a ground platform. We have succeeded to develop a scanning 1.6 μm DIAL and incoherent Doppler lidar system for simultaneously measuring CO2 concentration and wind speed profiles. Our 1.6 μm DIAL system consists of the Optical Parametric Generator (OPG) transmitter that excited by the LD pumped Nd: YAG laser with high repetition rate (500 Hz) and the receiving optics that included the near-infrared photomultiplier tube with high quantum efficiency operating at the photon counting mode, a fiber Bragg grating (FBG) filter to detect a Doppler shift, and a 25 cm telescope [1] [2]. We had developed an optical parametric oscillator (OPO) system for 1.6 μm CO2 DIAL[3]. To achieve continuous tuning of the resonant OPO output without mode hopping, it is necessary to vary the OPO cavity length synchronously with the seed-frequency. On the other hand, the OPG does not require a cavity and instead rely on sufficient conversion efficiency to be obtained with a single pass through the crystal. The single-frequency oscillation of the OPG was achieved by injection seeding. The CO2-DIAL was operated with the range-height indicator (RHI) mode, and the 2-D measurement provided inhomogeneity in the boundary layer. Vertical CO2 concentration profiles and wind profiles were also measured simultaneously. The elevation angle was fixed at 52 deg and CO2 concentration profiles were obtained up to 1 km altitude with 200 m height resolution. Vertical

  1. Implementing a Description Grammar Interpreter: A Notation for Descriptions and Description Rules

    Stouffs, R.M.F.

    2015-01-01

    Description grammars represent a formalism for generating verbal descriptions of designs, used in conjunction with shape grammars. A description grammar constitutes a set of description rules that define a language of descriptions. A description grammar interpreter implements the mechanisms to interpret descriptions and description rules, apply description rules to descriptions to derive new descriptions, and generate the members of the corresponding language of descriptions. In this paper, w...

  2. Monster telescope hunts blue planets

    Leake, J

    2003-01-01

    BRITAIN is to back a project to build the world's biggest telescope - so powerful that it could see life-bearing planets in other solar systems. It will need the largest mirror ever built at about 100 metres in diameter (1/2 page).

  3. Topological complexity of the telescope

    Franc, Aleksandra

    2015-01-01

    We use an alternative definition of topological complexity to show that the topological complexity of the mapping telescope of a sequence $X_1\\rightarrow X_2\\rightarrow X_3\\rightarrow...$ is bounded above by $2max{TC(X_i); i=1,2,...}$.

  4. Push-To Telescope Mathematics

    Teets, Donald

    2012-01-01

    Two coordinate systems are related here, one defined by the earth's equator and north pole, the other by the orientation of a telescope at some location on the surface of the earth. Applying an interesting though somewhat obscure property of orthogonal matrices and using the cross-product simplifies this relationship, revealing that a surprisingly…

  5. Characteristics and performance of the GAW experiment for a large field of view Cerenkov γ rays telescope

    The GAW project aims to test the feasibility of a new generation of Imaging Atmospheric Cherenkov Telescopes that join high flux sensitivity with Large Field of View capability. It consists of an array of 3 imaging Cherenkov telescopes each equipped with a Fresnel refractive lens of about 3.6 m2 geometrical area and an array of multi-anode photomultipliers at the focal surface operating in single photoelectron counting mode. Pointing along different North-South directions, GAW would reach a survey of 360 deg. x 60 deg. region of the sky. GAW is a collaboration effort of Research Institutes in Italy, Portugal and Spain

  6. The reflecting surface of the MAGIC-II Telescope

    Bastieri, D; Baixeras, C; Citterio, O; Dazzi, F; De Lotto, B; Doro, M; Ghigo, M; Giro, E; Göbel, F; Kosyra, R; Lorenz, E; Mariotti, M; Mirzoyan, R; Paoletti, R; Pareschi, G; Pascoli, D; Pepato, Adriano; Peruzzo, L; Saggion, A; Sartori, P; Sillanpää, A

    2007-01-01

    The MAGIC Collaboration is building a second telescope, MAGIC II, improving the design of the current MAGIC Telescope. MAGIC II is being built at 85 m of distance from MAGIC I, and will also feature a huge reflecting surface of ~240 m$^2$ of area. One of the improvement is the design for the mirror of MAGIC II, that are lighter and larger, being square of 1 m of side and weighting around 15 kg. For the development and production of the new mirrors, two different techniques, both reliable and affordable in price, were selected: the diamond milling of aluminium surfaces and the cold slumping of thin glass panes. As tests for the second one are still ongoing, we present a description of the diamond milling technique, and its application and performance to the produced mirrors.

  7. Segment Alignment Maintenance System for the Hobby-Eberly Telescope

    Rakoczy, John; Burdine, Robert (Technical Monitor)

    2001-01-01

    NASA's Marshall Space Flight Center, in collaboration with Blue Line Engineering of Colorado Springs, Colorado, is developing a Segment Alignment Maintenance System (SAMS) for McDonald Observatory's Hobby-Eberly Telescope (HET). The SAMS shall sense motions of the 91 primary mirror segments and send corrections to HET's primary mirror controller as the mirror segments misalign due to thermo -elastic deformations of the mirror support structure. The SAMS consists of inductive edge sensors. All measurements are sent to the SAMS computer where mirror motion corrections are calculated. In October 2000, a prototype SAMS was installed on a seven-segment cluster of the HET. Subsequent testing has shown that the SAMS concept and architecture are a viable practical approach to maintaining HET's primary mirror figure, or the figure of any large segmented telescope. This paper gives a functional description of the SAMS sub-array components and presents test data to characterize the performance of the subarray SAMS.

  8. New type of ferromagnetic insulator: Double perovskite La2NiMO6 (M=Mn, Tc, Re, Ti, Zr, and Hf)

    Electronic structures of transition metal pnictides double perovskite La2NiMO6 (M=Mn, Tc, Re, Ti, Zr, and Hf) were shown as ferromagnetic (FM) insulators based on density functional calculation results. The FM state observed in La2NiMO6 (M=Mn, Tc, and Re) was most likely a mixture of high spin (HS) and low spin (LS) states; the electrons were transferred from the filled LS Ni eg states to the half-filled HS Mn (Tc). On the other hand, the FM state in La2NiMO6 (M=Ti, Zr, and Hf) was caused by the electron transfer from the half-filled LS Ti (Zr and Hf) eg orbital of HS Ni to the empty eg orbital of LS Ti (Zr and Hf). The FM insulating state of La2NiMO6 (M=Mn. Tc, Ti, Zr, and Hf) remained the same, whereas it changed from metal to insulator for La2NiReO6 based on the generalized gradient approximation+U calculation

  9. Auxiliary full-disc telescope for the European Solar Telescope

    Sobotka, Michal; Klvaňa, Miroslav; Melich, Zbyněk; Rail, Zdeněk; Bettonvil, F.; Gelly, B.

    Bellingham : SPIE, 2010 - (McLean, I.), 77351Z-1-77351Z-8 ISBN 9780819482259. - (Proceedings of SPIE. 7735). [Ground-based and Airborne Instrumentation for Astronomy III. San Diego (US), 27.06.2010-02.07.2010] Grant ostatní: EU(XE) 212482 Institutional research plan: CEZ:AV0Z10030501; CEZ:AV0Z20430508 Keywords : auxiliary full-disc telescope * principal functions Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  10. Platform deformation refined pointing and phase correction for the AMiBA hexapod telescope

    Koch, Patrick; Kesteven, Michael; Chang, Yu-Yen; Huang, Yau-De; Raffin, Philippe; Chen, Ke-Yung; Chereau, Guillaume; Chen, Ming-Tang; Ho, Paul T. P.; Huang, Chih-Wie; Ibañez-Romano, Fabiola; Jiang, Homin; Liao, Yu-Wei; Lin, Kai-Yang; Liu, Guo-Chin; Molnar, Sandor; Nishioka, Hiroaki; Umetsu, Keiichi; Wang, Fu-Cheng; Wu, Jiun-Huei Proty; Altamirano, Pablo; Chang, Chiao-Hao; Chang, Shu-Hao; Chang, Su-Wei; Han, Chi-Chiang; Kubo, Derek; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter

    2008-07-01

    The Array for Microwave Background Anisotropy (AMiBA) is a radio interferometer for research in cosmology, currently operating 7 0.6m diameter antennas co-mounted on a 6m diameter platform driven by a hexapod mount. AMiBA is currently the largest hexapod telescope. We briefly summarize the hexapod operation with the current pointing error model. We then focus on the upcoming 13-element expansion with its potential difficulties and solutions. Photogrammetry measurements of the platform reveal deformations at a level which can affect the optical pointing and the receiver radio phase. In order to prepare for the 13-element upgrade, two optical telescopes are installed on the platform to correlate optical pointing tests. Being mounted on different locations, the residuals of the two sets of pointing errors show a characteristic phase and amplitude difference as a function of the platform deformation pattern. These results depend on the telescope's azimuth, elevation and polarization position. An analytical model for the deformation is derived in order to separate the local deformation induced error from the real hexapod pointing error. Similarly, we demonstrate that the deformation induced radio phase error can be reliably modeled and calibrated, which allows us to recover the ideal synthesized beam in amplitude and shape of up to 90% or more. The resulting array efficiency and its limits are discussed based on the derived errors.

  11. The Hubble Space Telescope: Problems and Solutions.

    Villard, Ray

    1990-01-01

    Presented is the best understanding of the flaw discovered in the optics of the Hubble Space Telescope and the possible solutions to the problems. The spherical aberration in the telescope's mirror and its effect on the quality of the telescope's imaging ability is discussed. (CW)

  12. The Baikal Neutrino Telescope: Status and plans

    Wischnewski, R; Baikal Collaboration

    2007-01-01

    The high energy neutrino telescope NT200+ is currently in operation in Lake Baikal. We review the status of the Baikal the Baikal Neutrino Telescope, and describe recent progress on key components of the next generation kilometer-cube (km3) Lake Baikal detector, like investigation of new large area phototubes, integrated into the telescope.

  13. 2m class telescope project at Lijiang

    Chen, Dong; Wang, Jian-Cheng; Xu, Jun; Zhang, Bai-Rong; Luo, Guo-Quan; Liu, Zhong; Tan, Hui-Song

    Supported by the ministry of science and technology, government of Yunnan Province and Chinese Academy of Sciences, a 2m class telescope project was granted. In this paper, we will first review the site, Gaomeigu, briefly, then give the details of 2m class telescope project, and finally discuss the future plans of this new telescope.

  14. The Optimal Gravitational Lens Telescope

    Surdej, J; Coleman, P; Dominik, M; Habraken, S; Hanot, C; Coroller, H Le; Mawet, D; Quintana, H; Sadibekova, T; Sluse, D; 10.1088/0004-6256/139/5/1935

    2010-01-01

    Given an observed gravitational lens mirage produced by a foreground deflector (cf. galaxy, quasar, cluster,...), it is possible via numerical lens inversion to retrieve the real source image, taking full advantage of the magnifying power of the cosmic lens. This has been achieved in the past for several remarkable gravitational lens systems. Instead, we propose here to invert an observed multiply imaged source directly at the telescope using an ad-hoc optical instrument which is described in the present paper. Compared to the previous method, this should allow one to detect fainter source features as well as to use such an optimal gravitational lens telescope to explore even fainter objects located behind and near the lens. Laboratory and numerical experiments illustrate this new approach.

  15. Focusing Telescopes in Nuclear Astrophysics

    Ballmoos, Peter von

    2007-01-01

    This volume is the first of its kind on focusing gamma-ray telescopes. Forty-eight refereed papers provide a comprehensive overview of the scientific potential and technical challenges of this nascent tool for nuclear astrophysics. The book features articles dealing with pivotal technologies such as grazing incident mirrors, multilayer coatings, Laue- and Fresnel-lenses - and even an optic using the curvature of space-time. The volume also presents an overview of detectors matching the ambitious objectives of gamma ray optics, and facilities for operating such systems on the ground and in space. The extraordinary scientific potential of focusing gamma-ray telescopes for the study of the most powerful sources and the most violent events in the Universe is emphasized in a series of introductory articles. Practicing professionals, and students interested in experimental high-energy astrophysics, will find this book a useful reference

  16. Cherenkov Telescope Array Data Management

    Lamanna, G; Contreras, J L; Knödlseder, J; Kosack, K; Neyroud, N; Aboudan, A; Arrabito, L; Barbier, C; Bastieri, D; Boisson, C; Brau-Nogué, S; Bregeon, J; Bulgarelli, A; Carosi, A; Costa, A; De Cesare, G; Reyes, R de los; Fioretti, V; Gallozzi, S; Jacquemier, J; Khelifi, B; Kocot, J; Lombardi, S; Lucarelli, F; Lyard, E; Maier, G; Massimino, P; Osborne, J P; Perri, M; Rico, J; Sanchez, D A; Satalecka, K; Siejkowski, H; Stolarczyk, T; Szepieniec, T; Testa, V; Walter, R; Ward, J E; Zoli, A

    2015-01-01

    Very High Energy gamma-ray astronomy with the Cherenkov Telescope Array (CTA) is evolving towards the model of a public observatory. Handling, processing and archiving the large amount of data generated by the CTA instruments and delivering scientific products are some of the challenges in designing the CTA Data Management. The participation of scientists from within CTA Consortium and from the greater worldwide scientific community necessitates a sophisticated scientific analysis system capable of providing unified and efficient user access to data, software and computing resources. Data Management is designed to respond to three main issues: (i) the treatment and flow of data from remote telescopes; (ii) "big-data" archiving and processing; (iii) and open data access. In this communication the overall technical design of the CTA Data Management, current major developments and prototypes are presented.

  17. Reconstruction of the HSFA telescopes

    Klvaňa, Miroslav; Kotrč, Pavel; Knížek, Miloslav; Sobotka, Michal; Heinzel, Petr

    2001-01-01

    Roč. 322, 5-6 (2001), s. 371-374. ISSN 0004-6337 R&D Projects: GA ČR GA205/01/0658; GA AV ČR KSK2043105; GA ČR GA205/00/1726 Institutional research plan: CEZ:AV0Z1003909 Keywords : solar horizontal telescope * spectrograph Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.503, year: 2001

  18. Fuzzy Description Logic Programs

    Straccia, Umberto

    2005-01-01

    emph{Description Logic Programs} (DLPs), which combine the expressive power of classical description logics and logic programs, are emerging as an important ontology description language paradigm. In this work, we present fuzzy DLPs, which extend DLPs by allowing the representation of vague/imprecise information.

  19. Acquisition of teleological descriptions

    Franke, David W.

    1992-03-01

    Teleology descriptions capture the purpose of an entity, mechanism, or activity with which they are associated. These descriptions can be used in explanation, diagnosis, and design reuse. We describe a technique for acquiring teleological descriptions expressed in the teleology language TeD. Acquisition occurs during design by observing design modifications and design verification. We demonstrate the acquisition technique in an electronic circuit design.

  20. Academic Training: Deep Space Telescopes

    Françoise Benz

    2006-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 20, 21, 22, 23, 24 February from 11:00 to 12:00 - Council Chamber on 20, 21, 23, 24 February, TH Auditorium, bldg 4 - 3-006, on 22 February Deep Space Telescopes G. BIGNAMI / CNRS, Toulouse, F & Univ. di Pavia, I The short series of seminars will address results and aims of current and future space astrophysics as the cultural framework for the development of deep space telescopes. It will then present such new tools, as they are currently available to, or imagined by, the scientific community, in the context of the science plans of ESA and of all major world space agencies. Ground-based astronomy, in the 400 years since Galileo's telescope, has given us a profound phenomenological comprehension of our Universe, but has traditionally been limited to the narrow band(s) to which our terrestrial atmosphere is transparent. Celestial objects, however, do not care about our limitations, and distribute most of the information about their physics thro...

  1. EUSO-TA prototype telescope

    Bisconti, Francesca

    2016-07-01

    EUSO-TA is one of the prototypes developed for the JEM-EUSO project, a space-based large field-of-view telescope to observe the fluorescence light emitted by cosmic ray air showers in the atmosphere. EUSO-TA is a ground-based prototype located at the Telescope Array (TA) site in Utah, USA, where an Electron Light Source and a Central Laser Facility are installed. The purpose of the EUSO-TA project is to calibrate the prototype with the TA fluorescence detector in presence of well-known light sources and cosmic ray air showers. In 2015, the detector started the first measurements and tests using the mentioned light sources have been performed successfully. A first cosmic ray candidate has been observed, as well as stars of different magnitude and color index. Since Silicon Photo-Multipliers (SiPMs) are very promising for fluorescence telescopes of next generation, they are under consideration for the realization of a new prototype of EUSO Photo Detector Module (PDM). The response of this sensor type is under investigation through simulations and laboratory experimentation.

  2. The space telescope: A study of NASA, science, technology, and politics

    Smith, Robert William

    1989-01-01

    Scientific, technological, economic, and political aspects of NASA efforts to orbit a large astronomical telescope are examined in a critical historical review based on extensive interviews with participants and analysis of published and unpublished sources. The scientific advantages of large space telescopes are explained; early plans for space observatories are summarized; the history of NASA and its major programs is surveyed; the redesign of the original Large Space Telescope for Shuttle deployability is discussed; the impact of the yearly funding negotiations with Congress on the development of the final Hubble Space Telescope (HST) is described; and the implications of the HST story for the future of large space science projects are explored. Drawings, photographs, a description of the HST instruments and systems, and lists of the major contractors and institutions participating in the HST program are provided.

  3. Cost Modeling for Space Optical Telescope Assemblies

    Stahl, H. Philip; Henrichs, Todd; Luedtke, Alexander; West, Miranda

    2011-01-01

    Parametric cost models are used to plan missions, compare concepts and justify technology investments. This paper reviews an on-going effort to develop cost modes for space telescopes. This paper summarizes the methodology used to develop cost models and documents how changes to the database have changed previously published preliminary cost models. While the cost models are evolving, the previously published findings remain valid: it costs less per square meter of collecting aperture to build a large telescope than a small telescope; technology development as a function of time reduces cost; and lower areal density telescopes cost more than more massive telescopes.

  4. Hard X-ray Modulation Telescope

    LU Fangjun

    2011-01-01

    The Hard X-ray Modulation Telescope (HXMT) will be China's first astronomical satellite. On board HXMT there are three kinds of slat-collimated telescopes, the High Energy X-ray Telescope (HE, 20-250 keV, 5000 cm^2), the Medium Energy X-ray Telescope (ME, 5-30 keV, 952 cm^2), and the Low Energy X-ray Telescope (LE, 1-15 keV, 384 cm^2).

  5. Astrophysical results of the Mauritius radio telescope

    One of the first scientific justifications of building the Mauritius Radio Telescope (hereafter referred to as MRT) was to complement the Cambridge 6C survey, which is a radio map of most of the northern sky at 150 MHz [1]; the MRT would then be the equivalent of the 6C survey for the southern sky and together we would obtain a whole sky radio map at 150 MHz. When the MRT was built, there were no radio surveys of the southern sky at frequencies less than 408 MHz; the frequency of 150 MHz was also chosen to complement the other radio surveys of the southern sky, which have been done at higher frequencies. Furthermore low radio frequencies like 150 MHz are bound to see new sources that would have been missed at higher frequencies due to the form of their spectra. Interesting features of resolved objects can also be studied in more details. In this paper, a brief description of the MRT will be made as well as the observations and imaging with the MRT data, and some astrophysical results obtained since its commissioning in 1992 (20 years of existence this year 2012).

  6. 研华推出Atom双核ARK-6320-6M01E无风扇嵌入式工控机

    2010-01-01

    面对工控行业的低功耗趋势,研华推出了紧凑、低功耗、功能强大的Mini-ITX嵌入式工控机ARK-6320—6M01E。ARK-6320—6M01采用了双核IntelAtomTMD510处理器,工作静音,并可在恶劣环境中稳定运行。它具有很强的扩展能力,是热门的多合一嵌入式工控机,适合于工业自动化、KIOSK/POS.数字标牌(DSA)以及其他嵌入式应用。

  7. 研华推出Atom双核ARK-6320—6M01E无风扇嵌入式工控机

    2010-01-01

    研华近期推出了紧凑、低功耗、功能强大的Mini—ITX嵌入式工控机ARK-6320—6M01E。ARK-6320—6M01采用了双核Intel?Atom TM D510处理器,工作静音,并可在恶劣环境中稳定运行。它具有很强的扩展能力,是最热门的多合一嵌入式工控机,适合于工业自动化、KIOSK/POS,数字标牌(DSA)以及其他嵌入式应用。

  8. Correlation Between Mucosal IL-6 mRNA Expression Level and Virulence Factors of Helicobacter pylori in Iranian Adult Patients With Chronic Gastritis

    Azadegan-Dehkordi, Fatemeh; Bagheri, Nader; Shirzad, Mahsa; Sanei, Mohammad Hossein; Hashemzadeh-Chaleshtori, Morteza; Rafieian-Kopaei, Mahmoud; Tabatabaiefar, Mohammad Amin; Shirzad, Hedayatollah

    2015-01-01

    Background: Helicobacter pylori infection is associated with gastritis and marked infiltration of the gastric mucosa by several cytokines secreting inflammatory cells that contribute to sustained local inflammation. In this study, we sought to examine IL-6 expression in H. pylori-infected and uninfected gastric mucosa and elucidate the implication in the pathogenesis of H. pylori-associated gastritis in human. Objectives: The current study aimed to determine mucosal IL-6 mRNA expression level...

  9. Mechanical properties and electronic structures of M{sub 23}C{sub 6} (M = Fe, Cr, Mn)-type multicomponent carbides

    Liu, Yangzhen [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650093 (China); State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an, Shaanxi, 710049 (China); Jiang, Yehua, E-mail: jiangyehua@kmust.edu.cn [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650093 (China); Xing, Jiandong [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an, Shaanxi, 710049 (China); Zhou, Rong [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650093 (China); Feng, Jing, E-mail: jfeng@seas.harvard.edu [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650093 (China); School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02318 (United States)

    2015-11-05

    The mechanical and electronic properties of M{sub 23}C{sub 6}- (M = Fe, Cr, Mn) and M{sub 23}C{sub 6}-type multicomponent carbides are investigated systematically by first-principles calculations. The values of cohesive energy and formation enthalpy exhibited thermodynamically stable structures of these carbides. The stress–strain method and Voigt-Reuss-Hill approximation were used to calculate the elastic constants and moduli, respectively. The mechanical properties of the doped Fe or Mo in M{sub 23}C{sub 6} compounds are superior to the pure phases of Cr{sub 23}C{sub 6}, Mn{sub 23}C{sub 6} and Fe{sub 23}C{sub 6}. Mechanical anisotropy of these compounds was illustrated from the anisotropic index and different shapes of the surface contour by Young's modulus. Moreover, the total density of states of M{sub 23}C{sub 6} compounds indicated that the bonding behaviors of M{sub 23}C{sub 6} compounds were combinations of metallic and covalent bonds. - Graphical abstract: The crystal structure of M{sub 23}C{sub 6} (M = Cr, Mn, Fe, Mo, W), which formed in different heat treatment of many iron-based alloys can dramatically influence the mechanical properties of materials such as extreme hardness, high melting point, wear resistance, corrosion resistance and high thermal conductivity, etc. - Highlights: • The mechanical properties of M{sub 23}C{sub 6} (M = Fe, Cr, Mn) multicomponent carbides are estimated. • The anisotropy of M{sub 23}C{sub 6} carbides are discussed with regards to bonding and density of states. • M{sub 23}C{sub 6} (M = Fe, Cr, Mn) multicomponent carbides are thermodynamically stable.

  10. The cellular uptake of antisense oligonucleotid of E6 mRNA into cervical cancer cells by DOPE-modified hydroxyapatite nanoparticles

    Negin Saffarzadeh; Seyed Mehdi Kalantar; Ali Jebali; Seyed Hossein Hekmatimoghaddam; Mohammad Hassan Sheikhha; Ehsan Farashahi

    2014-01-01

    Objective(s): Although several chemical and physical methods for gene delivery have been introduced, their cytotoxicity, non-specific immune responses and the lack of biodegradability remain the main issues. In this study, hydroxyapatite nanoparticles (NPs) and 1,2-dioleoyl-sn-glycero-3-phosphoethanol​amine (DOPE)-modified hydroxyapatite NPs was coated with antisense oligonucleotide of E6 mRNA, and their uptakes into the cervical cancer cell line were evaluated. Materials and Methods: Calcium...

  11. Status of the Cherenkov Telescope Array's Large Size Telescopes

    Cortina, J

    2015-01-01

    The Cherenkov Telescope Array (CTA) observatory, will be deployed over two sites in the two hemispheres. Both sites will be equipped with four Large Size Telescopes (LSTs), which are crucial to achieve the science goals of CTA in the 20-200 GeV energy range. Each LST is equipped with a primary tessellated mirror dish of 23 m diameter, supported by a structure made mainly of carbon fibre reinforced plastic tubes and aluminum joints. This solution guarantees light weight (around 100 tons), essential for fast repositioning to any position in the sky in <20 seconds. The camera is composed of 1855 PMTs and embeds the control, readout and trigger electronics. The detailed design is now complete and production of the first LST, which will serve as a prototype for the remaining seven, is well underway. In 2016 the first LST will be installed at the Roque de los Muchachos Observatory on the Canary island of La Palma (Spain). In this talk we will outline the technical solutions adopted to fulfill the design requirem...

  12. The Northwest Indiana Robotic Telescope

    Slavin, Shawn D.; Rengstorf, A. W.; Aros, J. C.; Segally, W. B.

    2011-01-01

    The Northwest Indiana Robotic (NIRo) Telescope is a remote, automated observing facility recently built by Purdue University Calumet (PUC) at a site in Lowell, IN, approximately 30 miles from the PUC campus. The recently dedicated observatory will be used for broadband and narrowband optical observations by PUC students and faculty, as well as pre-college students through the implementation of standards-based, middle-school modules developed by PUC astronomers and education faculty. The NIRo observatory and its web portal are the central technical elements of a project to improve astronomy education at Purdue Calumet and, more broadly, to improve science education in middle schools of the surrounding region. The NIRo Telescope is a 0.5-meter (20-inch) Ritchey-Chrétien design on a Paramount ME robotic mount, featuring a seven-position filter wheel (UBVRI, Hα, Clear), Peltier (thermoelectrically) cooled CCD camera with 3056 x 3056, square, 12 μm pixels, and off-axis guiding. It provides a coma-free imaging field of 0.5 degrees square, with a plate scale of 0.6 arcseconds per pixel. The observatory has a wireless internet connection, local weather station which publishes data to an internet weather site, and a suite of CCTV security cameras on an IP-based, networked video server. Control of power to every piece of instrumentation is maintained via internet-accessible power distribution units. The telescope can be controlled on-site, or off-site in an attended fashion via an internet connection, but will be used primarily in an unattended mode of automated observation, where queued observations will be scheduled daily from a database of requests. Completed observational data from queued operation will be stored on a campus-based server, which also runs the web portal and observation database. Partial support for this work was provided by the National Science Foundation's Course, Curriculum, and Laboratory Improvement (CCLI) program under Award No. 0736592.

  13. LLCD operations using the Optical Communications Telescope Laboratory (OCTL)

    Biswas, Abhijit; Kovalik, Joseph M.; Wright, Malcolm W.; Roberts, William T.; Cheng, Michael K.; Quirk, Kevin J.; Srinivasan, Meera; Shaw, Matthew D.; Birnbaum, Kevin M.

    2014-03-01

    The Optical Communications Telescope Laboratory (OCTL) located on Table Mountain near Wrightwood, CA served as an alternate ground terminal to the Lunar Laser Communications Demonstration (LLCD), the first free-space laser communication demonstration from lunar distances. The Lunar Lasercom OCTL Terminal (LLOT) Project utilized the existing 1m diameter OCTL telescope by retrofitting: (i) a multi-beam 1568 nm laser beacon transmitter; (ii) a tungsten silicide (WSi) superconducting nanowire single photon detector (SNSPD) receiver for 1550 nm downlink; (iii) a telescope control system with the functionality required for laser communication operations; and (iv) a secure network connection to the Lunar Lasercom Operations Center (LLOC) located at the Lincoln Laboratory, Massachusetts Institute of Technology (LL-MIT). The laser beacon transmitted from Table Mountain was acquired by the Lunar Lasercom Space Terminal (LLST) on-board the Lunar Atmospheric Dust Environment Explorer (LADEE) spacecraft and a 1550 nm downlink at 39 and 78 Mb/s was returned to LLOT. Link operations were coordinated by LLOC. During October and November of 2013, twenty successful links were accomplished under diverse conditions. In this paper, a brief system level description of LLOT along with the concept of operations and selected results are presented.

  14. The stellar scintillation on large and extremely large telescopes

    Kornilov, Victor

    2012-01-01

    The accuracy of ground-based astronomical photometry is limited by two factors: photon statistics and stellar scintillation arising when star light passes through Earth's atmosphere. This paper examines the theoretical role of the outer scale $L_0$ of the optical turbulence (OT) which suppresses the low-frequency component of scintillation. It is shown that for typical values of $L_0 \\sim 25 - 50$ m, this effect becomes noticeable for a telescopes of diameter around 4 m. On extremely large, $30 - 40$ m, telescopes with exposures longer than a few seconds, the inclusion of the outer scale in the calculation reduces the scintillation power by more than a factor of 10 relative to conventional estimates. The details of this phenomenon are discussed for various models of non-Kolmogorov turbulence. Also, a quantitative description of the influence of the telescope central obscuration on the measured scintillation noise is introduced and combined with the effect of the outer scale. Evaluation of the scintillation no...

  15. Future Plans of Telescope Array

    The Telescope Array (TA) experiment is the only ultra high energy cosmic ray observatory in the northern hemisphere. In addition, it will be the world's first air shower detector to be directly calibrated by an on-site accelerator beam. For wider and deeper understanding of cosmic rays by via high precision measurements, we have undertaken the study of extension plans for TA. One extension plan will extend the sensitive energy range of TA down to 1017 eV. A second plan would extend of the aperture area of the SD array. These plans are described in this note.

  16. Scientific Potential of Einstein Telescope

    Sathyaprakash, B; Acernese, F; Andersson, P Amaro-Seoane N; Arun, K; Barone, F; Barr, B; Barsuglia, M; Beveridge, M Beker N; Birindelli, S; Bose, S; Bosi, L; Braccini, S; Bradaschia, C; Bulik, T; Calloni, E; Cella, G; Mottin, E Chassande; Chelkowski, S; Chincarini, A; Clark, J; Coccia, E; Colacino, C; Colas, J; Cumming, A; Cunningham, L; Cuoco, E; Danilishin, S; Danzmann, K; Salvo, R De; Dent, T; Rosa, R De; Fiore, L Di; Virgilio, A Di; Doets, M; Fafone, V; Falferi, P; Flaminio, R; Franc, J; Frasconi, F; Freise, A; Friedrich, D; Fulda, P; Gair, J; Gemme, G; Genin, E; Gennai, A; Giazotto, A; Glampedakis, K; Gräf, C; Granata, M; Grote, H; Guidi, G; Gurkovsky, A; Hammond, G; Hannam, M; Harms, J; Heinert, D; Hendry, M; Heng, I; Hennes, E; Hild, S; Hough, J; Husa, S; Huttner, S; Jones, G; Khalili, F; Kokeyama, K; Kokkotas, K; Krishnan, B; Li, T G F; Lorenzini, M; Lück, H; Majorana, E; Mandel, I; Mandic, V; Mantovani, M; Martin, I; Michel, C; Minenkov, Y; Morgado, N; Mosca, S; Mours, B; Müller--Ebhardt, H; Murray, P; Nawrodt, R; Nelson, J; Oshaughnessy, R; Ott, C D; Palomba, C; Paoli, A; Parguez, G; Pasqualetti, A; Passaquieti, R; Passuello, D; Pinard, L; Plastino, W; Poggiani, R; Popolizio, P; Prato, M; Punturo, M; Puppo, P; Rabeling, D; Racz, I; Rapagnani, P; Read, J; Regimbau, T; Rehbein, H; Reid, S; Rezzolla, L; Ricci, F; Richard, F; Rocchi, A; Rowan, S; Rüdiger, A; Santamaría, L; Sassolas, B; Schnabe, R; Schwarz, C; Seidel, P; Sintes, A; Somiya, K; Speirits, F; Strain, K; Strigin, S; Sutton, P; Tarabrin, S; Thüring, A; Brand, J van den; Veggel, M van; Broeck, C van den; Vecchio, A; Veitch, J; Vetrano, F; Vicere, A; Vyatchanin, S; Willke, B; Woan, G; Yamamoto, K

    2011-01-01

    Einstein gravitational-wave Telescope (ET) is a design study funded by the European Commission to explore the technological challenges of and scientific benefits from building a third generation gravitational wave detector. The three-year study, which concluded earlier this year, has formulated the conceptual design of an observatory that can support the implementation of new technology for the next two to three decades. The goal of this talk is to introduce the audience to the overall aims and objectives of the project and to enumerate ET's potential to influence our understanding of fundamental physics, astrophysics and cosmology.

  17. Space Telescope performance and verification

    Wright, W. F.

    1980-01-01

    The verification philosophy for the Space Telescope (ST) has evolved from years of experience with multispacecraft programs modified by the new factors introduced by the Space Transportation System. At the systems level of test, the ST will undergo joint qualification/acceptance tests with environment simulation using Lockheed's large spacecraft test facilities. These tests continue the process of detecting workmanship defects and module interface incompatibilities. The test program culminates in an 'all up' ST environmental test verification program resulting in a 'ready to launch' ST.

  18. Milord II. Language description.

    Puyol-Gruart, Josep; Sierra, Carles

    1997-01-01

    In this paper we describe the language Milord II. The description is made in terms of computer language concepts and not in terms of the logical semantics underlying it. In this sense the paper complements others in which the focus of the description has been either the object level multi-valued language description, or the reflective component of the architecture, or even the several applications built using it. All the necessary elements to understand how a system programmed in Milord II ex...

  19. Milord II: language description

    Puyol-Gruart, Josep; Sierra Garriga, Carlos

    1997-01-01

    In this paper we describe the language Milord. The description is made in terms of computer language concepts and not in terms of the logical semantics underlying it. In this sense the paper complements others in which the focus of the description has been either the object level multi-valued language description, or the reflective component of the architecture, or even the several applications built using it. All the necessary elements to understand how a system programmed in Milord e...

  20. Multimedia content description framework

    Bergman, Lawrence David (Inventor); Kim, Michelle Yoonk Yung (Inventor); Li, Chung-Sheng (Inventor); Mohan, Rakesh (Inventor); Smith, John Richard (Inventor)

    2003-01-01

    A framework is provided for describing multimedia content and a system in which a plurality of multimedia storage devices employing the content description methods of the present invention can interoperate. In accordance with one form of the present invention, the content description framework is a description scheme (DS) for describing streams or aggregations of multimedia objects, which may comprise audio, images, video, text, time series, and various other modalities. This description scheme can accommodate an essentially limitless number of descriptors in terms of features, semantics or metadata, and facilitate content-based search, index, and retrieval, among other capabilities, for both streamed or aggregated multimedia objects.

  1. ANTARES: An Undersea Neutrino telescope

    2002-01-01

    The ANTARES (Astronomy with a Neutrino Telescope and ${Abyss}$ environmental RESearch) deep-sea neutrino telescope is designed to search for neutrinos of astrophysical origin. Neutrinos are unique probes of the high energy universe; being neutral they are not deflected by magnetic fields and interacting weakly they can readily escape from the densest regions of the universe. Potential sources of neutrino are galactic (e.g supernova remnants, micro-quasars) and extra-galactic (e.g active galactic nuclei, gamma-ray bursters). Annihilation of dark matter particles in the Sun or Galactic Centre is another well motivated potential source of extra terrestrial neutrinos. The ANTARES detector is located 40 km off the coast of Toulon (France) at a depth of 2475m in the Mediterranean Sea. Being located in the Northern hemisphere it studies the Southern sky and in particular has the Galactic Centre in its field of view. Since 2006, the detector has operated continuously in a partial configuration. The detector was compl...

  2. TMT telescope structure thermal model

    Vogiatzis, Konstantinos; Sadjadpour, Amir; Roberts, Scott

    2014-08-01

    The thermal behavior of the Thirty Meter Telescope (TMT) Telescope Structure (STR) and the STR mounted subsystems depends on the heat load of the System, the thermal properties of component materials and the environment as well as their interactions through convection, conduction and radiation. In this paper the thermal environment is described and the latest three-dimensional Computational Solid Dynamics (CSD) model is presented. The model tracks the diurnal temperature variation of the STR and the corresponding deformations. The resulting displacements are fed into the TMT Merit Function Routine (MFR), which converts them into translations and rotations of the optical surfaces. They, in turn, are multiplied by the TMT optical sensitivity matrix that delivers the corresponding pointing error. Thus the thermal performance of the structure can be assessed for requirement compliance, thermal drift correction strategies and look-up tables can be developed and design guidance can be provided. Results for a representative diurnal cycle based on measured temperature data from the TMT site on Mauna Kea and CFD simulations are presented and conclusions are drawn.

  3. JWST Telescope Integration and Test Progress

    Matthews, Gary W.; Whitman, Tony L.; Feinberg, Lee D.; Voyton, Mark F.; Lander, Juli A.; Keski-Kuha, Ritva

    2016-01-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. The JWST Optical Telescope Element (Telescope) integration and test program is well underway. The telescope was completed in the spring of 2016 and the cryogenic test equipment has been through two optical test programs leading up to the final flight verification program. The details of the telescope mirror integration will be provided along with the current status of the flight observatory. In addition, the results of the two optical ground support equipment cryo tests will be shown and how these plans fold into the flight verification program.

  4. An Overview of Integration and Test of the James Webb Space Telescope Integrated Science Instrument Module

    Drury, Michael; Becker, Neil; Bos, Brent; Davila, Pamela; Frey, Bradley; Hylan, Jason; Marsh, James; McGuffey, Douglas; Novak, Maria; Ohl, Raymond; Redman, Kevin; Sampler, Henry; Sullivan, Joseph; Walker, Ian; Wright, Geraldine; Young, Philip

    2007-01-01

    The James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (approx.40K). The JWST Observatory architecture includes the Optical Telescope Element (OTE) and the Integrated Science Instrument Module (ISIM) element that contains four science instruments (SI) including a Guider. The SIs and Guider are mounted to a composite metering structure with outer dimensions of 2.1x2.2x1.9m. The SI and Guider units are integrated to the ISIM structure and optically tested at NASA/Goddard Space Flight Center as an instrument suite using a high-fidelity, cryogenic JWST telescope simulator that features a 1.5m diameter powered mirror. The SIs are integrated and aligned to the structure under ambient, clean room conditions. SI performance, including focus, pupil shear and wavefront error, is evaluated at the operating temperature. We present an overview of the ISIM integration within the context of Observatory-level construction. We describe the integration and verification plan for the ISIM element, including an overview of our incremental verification approach, ambient mechanical integration and test plans and optical alignment and cryogenic test plans. We describe key ground support equipment and facilities.

  5. ANTARES: The first undersea neutrino telescope

    The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given.

  6. ANTARES: The first undersea neutrino telescope

    Ageron, M. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Aguilar, J.A. [IFIC-Instituto de Fisica Corpuscular, Edificios Investigacion de Paterna, CSIC-Universitat de Valencia, Apdo. de Correos 22085, 46071 Valencia (Spain); Al Samarai, I. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Albert, A. [GRPHE-Institut universitaire de technologie de Colmar, 34 rue du Grillenbreit BP 50568, 68008 Colmar (France); Ameli, F. [INFN-Sezione di Roma, P.le Aldo Moro 2, 00185 Roma (Italy); Andre, M. [Technical University of Catalonia, Laboratory of Applied Bioacoustics, Rambla Exposicio, 08800 Vilanova i la Geltru, Barcelona (Spain); Anghinolfi, M. [INFN-Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Anton, G. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Anvar, S. [Direction des Sciences de la Matiere-Institut de recherche sur les lois fondamentales de l' Univers-Service d' Electronique des Detecteurs et d' Informatique, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); Ardid, M. [Institut d' Investigacio per a la Gestio Integrada de Zones Costaneres (IGIC)-Universitat Politecnica de Valencia. C/Paranimf 1., 46730 Gandia (Spain); Arnaud, K.; Aslanides, E. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Assis Jesus, A.C.; Astraatmadja, T. [Nikhef, Science Park, Amsterdam (Netherlands); Aubert, J.-J. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Auer, R. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Barbarito, E. [INFN-Sezione di Bari, Via E. Orabona 4, 70126 Bari (Italy); Baret, B. [APC-Laboratoire AstroParticule et Cosmologie, UMR 7164 (CNRS, Universite Paris 7 Diderot, CEA, Observatoire de Paris), 10 rue Alice Domon et Leonie Duquet, 75205 Paris Cedex 13 (France); and others

    2011-11-11

    The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given.

  7. EUDET Telescope Geometry and Resolution Studies

    ZARNECKI, A F; Niezurawski, P.

    2007-01-01

    Construction of EUDET pixel telescope will significantly improve the test beam infrastructure for the ILC vertex detector studies. The telescope, based on the Monolithic Active Pixel Sensors (MAPS), will consist of up to six readout planes and will be initially installed at an electron beam line at DESY. A dedicated study was performed to understand the position measurement in the telescope and optimize its performance by suggesting the best plane setup. The approach based on the analytical t...

  8. ANTARES: The first undersea neutrino telescope

    Ageron, M.; H. van Haren; ANTARES Collaboration

    2011-01-01

    The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given.

  9. The Dutch Open Telescope: History, Status, Prospects

    Rutten, R. J.

    2001-01-01

    After many years of persistent telescope design and telescope construction, R.H. Hammerschlag has installed his Dutch Open Telescope (DOT) on La Palma. I brie y review its history and design. The future of optical solar physics at Utrecht hinges on a recently-funded three- year DOT science validation period. The initial aim is to obtain high- resolution image sequences in the G band, Ca II K and H as proxy- magnetometry in support of SOHO and TRACE.

  10. How to focus a Cherenkov telescope

    Hofmann, Werner

    2001-01-01

    Cherenkov telescopes image the Cherenkov emission from air showers. A priori, it is not obvious if the `best' images are achieved by measuring Cherenkov photon angles, i.e. focusing the telescope at infinity, or by considering the air shower as an object to be imaged, in which case one might focus the telescope on the central region of the shower. The issue is addressed using shower simulations.

  11. Herschel SPIRE FTS telescope model correction

    Hopwood, Rosalind; Fulton, Trevor; Polehampton, Edward T.; Valtchanov, Ivan; Benielli, Dominique; Imhof, Peter; Lim, Tanya; Lu, Nanyao; Marchili, Nicola; Pearson, Chris P.; Swinyard, Bruce M.

    2014-01-01

    Emission from the Herschel telescope is the dominant source of radiation for the majority of SPIRE Fourier transform spectrometer (FTS) observations, despite the exceptionally low emissivity of the primary and secondary mirrors. Accurate modelling and removal of the telescope contribution is, therefore, an important and challenging aspect of FTS calibration and data reduction pipeline. A dust-contaminated telescope model with time invariant mirror emissivity was adopted before the Herschel la...

  12. The Timepix Telescope for high performance particle tracking

    Akiba, K. [Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Ronning, P. [CERN, The European Organisation for Nuclear Research, Geneva (Switzerland); Beuzekom, M. van; Beveren, V. van [NIKHEF, Amsterdam (Netherlands); Borghi, S. [University of Manchester, Manchester, Lancashire (United Kingdom); Boterenbrood, H. [NIKHEF, Amsterdam (Netherlands); Buytaert, J.; Collins, P. [CERN, The European Organisation for Nuclear Research, Geneva (Switzerland); Dosil Suárez, A. [Universidade de Santiago de Compostela, Santiago de Compostela (Spain); Dumps, R. [CERN, The European Organisation for Nuclear Research, Geneva (Switzerland); Eklund, L. [Glasgow University, Glasgow, Lanarkshire (United Kingdom); Esperante, D.; Gallas, A. [Universidade de Santiago de Compostela, Santiago de Compostela (Spain); Gordon, H. [University of Oxford, Oxfordshire (United Kingdom); Heijden, B. van der [NIKHEF, Amsterdam (Netherlands); Hombach, C. [University of Manchester, Manchester, Lancashire (United Kingdom); Hynds, D. [Glasgow University, Glasgow, Lanarkshire (United Kingdom); John, M. [University of Oxford, Oxfordshire (United Kingdom); Leflat, A. [Lomonosov Moscow State University, Moscow (Russian Federation); Li, Y. [University of Oxford, Oxfordshire (United Kingdom); and others

    2013-09-21

    The Timepix particle tracking telescope has been developed as part of the LHCb VELO Upgrade project, supported by the Medipix Collaboration and the AIDA framework. It is a primary piece of infrastructure for the VELO Upgrade project and is being used for the development of new sensors and front end technologies for several upcoming LHC trackers and vertexing systems. The telescope is designed around the dual capability of the Timepix ASICs to provide information about either the deposited charge or the timing information from tracks traversing the 14×14 mm matrix of 55×55μm pixels. The rate of reconstructed tracks available is optimised by taking advantage of the shutter driver readout architecture of the Timepix chip, operated with existing readout systems. Results of tests conducted in the SPS North Area beam facility at CERN show that the telescope typically provides reconstructed track rates during the beam spills of between 3.5 and 7.5 kHz, depending on beam conditions. The tracks are time stamped with 1 ns resolution with an efficiency of above 98% and provide a pointing resolution at the centre of the telescope of ∼1.6μm. By dropping the time stamping requirement the rate can be increased to ∼15kHz, at the expense of a small increase in background. The telescope infrastructure provides CO{sub 2} cooling and a flexible mechanical interface to the device under test, and has been used for a wide range of measurements during the 2011–2012 data taking campaigns. -- Highlights: • We provide a technical description of the Timepix Telescope for particle tracking applications. • We demonstrate the spatial and timing resolution to be 2μm and 1 ns respectively. • The maximum particle rate is 7.5 kHz with highly resolved timing and spacing. • The maximum particle rate is 15 kHz with only highly resolved spacing. • We briefly describe the software and tracking algorithms used to achieve this.

  13. GRANITE- A steroscopic imaging Chernkov telescope system

    A second 10 meter class imaging telescope was constructed on Mt. Hopkins, Arizona, the site of the original 10 meter Whipple Cherenkov telescope. The twin telescope system with a 140 meter base line will allow both a reduction in the energy threshold and an improvement in the rejection of the hardonic background. The new telescope started operation in December 1991. With the final completion of the first installation stage (GRANITE I) during spring 92, it is now operating simultaneously with the orginal reflector. We describe in this paper design and construction of the new instrument and demonstrate the capability of the experiment to record coincident events

  14. European Extremely Large Telescope: progress report

    Tamai, R.; Spyromilio, J.

    2014-07-01

    The European Extremely Large Telescope is a project of the European Southern Observatory to build and operate a 40-m class optical near-infrared telescope. The telescope design effort is largely concluded and construction contracts are being placed with industry and academic/research institutes for the various components. The siting of the telescope in Northern Chile close to the Paranal site allows for an integrated operation of the facility providing significant economies. The progress of the project in various areas is presented in this paper and references to other papers at this SPIE meeting are made.

  15. Descriptive set theory

    Moschovakis, YN

    1987-01-01

    Now available in paperback, this monograph is a self-contained exposition of the main results and methods of descriptive set theory. It develops all the necessary background material from logic and recursion theory, and treats both classical descriptive set theory and the effective theory developed by logicians.

  16. Re-t2g-splitting-driven semiconductor gaps in ferrimagnetic double perovskite Ca2MReO6 (M=Cr,Fe) from first principles

    Gong, Sai; Guo, San-Dong; Chen, Peng; Liu, Bang-Gui

    2014-01-01

    Motivated by the observation of nonmetallic nature in double perovskite Ca2CrReO6 and Ca2FeReO6 with high magnetic Curie temperatures of 360 and 522 K, we systematically investigate the structural, electronic, and magnetic properties of Ca2MReO6 (M=Cr,Fe) using the full-potential linear augmented plane wave (FP-LAPW) method within the density functional theory. Our full optimization confirms the stable ground-state structure with $P2_1/n$ symmetry. The modified Becke-Johnson (mBJ) exchange po...

  17. Tracheal overexpression of IL-1β, IRAK-1 and TRAF-6 mRNA in obese-asthmatic male Wistar rats

    Mohammad Reza Aslani; Rana Keyhanmanesh; Amir Mehdi Khamaneh; Mehran Mesgari Abbasi; Maryam Fallahi; Mohammad Reza Alipour

    2016-01-01

    Objective(s): Human and animal studies have shown a close relationship between obesity and asthma severity. Here, we examined the effects of diet-induced obesity (DIO) on the expression levels of IL-1β, IRAK-1 and TRAF-6 mRNA in male Wistar rats tracheal after sensitization with ovalbumin (OVA). Materials and Methods:Twenty male Wistar rats divided to four groups, included, control group with normal diet (C+ND), OVA-sensitized group with normal diet (S+ND), control group with high-fat diet...

  18. Structure and Physical properties of New layered oxypnictides $Sr_4Sc_2O_6M_2As_2$ (M=Fe and Co)

    Xie, Y. L.; Liu, R. H.; Wu, T; G Wu; Song, Y. A.; Tan, D; Wang, X F; Chen, H.; Ying, J. J.; Y. J. Yan; Li, Q. J.; Chen, X. H.

    2009-01-01

    We have successfully prepared the new layered oxypnictides $Sr_4Sc_2O_6M_2As_2$ (M=Fe and Co). They adopt the tetragonal structure, being the same as that of $Sr_4Sc_2O_6Fe_2P_2$. The lattice constants are a=0.4045 nm and c= 0.5802 nm for M=Fe, and a=0.4045 nm and c=1.5695 nm for M=Co, respectively. Their transport and magnetic properties have been systematically studied. The temperature dependence of Hall coefficient and thermoelectric powder for $Sr_4Sc_2O_6Fe_2As_2$ compound show complicat...

  19. SkyView Virtual Telescope:

    McGlynn, Thomas A.; McDonald, Laura M.; Scollick, Keith A.

    2015-11-01

    The SkyView Virtual telescope provides access to survey datasets ranging from radio through the gamma-ray regimes. Over 100 survey datasets are currently available. The SkyView library referenced here is used as the basis for the SkyView web site (at http://skvyiew.gsfc.nasa.gov) but is designed for individual use by researchers as well. SkyView's approach to access surveys is distinct from most other toolkits. Rather than providing links to the original data, SkyView attempts to immediately re-render the source data in the user-requested reference frame, projection, scaling, orientation, etc. The library includes a set of geometry transformation and mosaicking tools that may be integrated into other applications independent of SkyView.

  20. Adaptive Optics for Large Telescopes

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments

  1. Recent Results from Telescope Array

    Fukushima, M

    2015-01-01

    The Telescope Array (TA) is an experiment to observe Ultra-High Energy Cosmic Rays (UHECRs). TA's recent results, the energy spectrum and anisotropy based on the 6-year surface array data, and the primary composition obtained from the shower maximum Xmax are reported. The spectrum demonstrates a clear dip and cutoff. The shape of the spectrum is well described by the energy loss of extra-galactic protons interacting with the cosmic microwave background (CMB). Above the cutoff, a medium-scale (20 degrees radius) flux enhancement was observed near the Ursa-Major. A chance probability of creating this hotspot from the isotropic flux is 4.0 sigma. The measured Xmax is consistent with the primary being proton or light nuclei for energies 10^18.2 eV - 10^19.2 eV.

  2. Adaptive Optics for Large Telescopes

    Olivier, S

    2008-06-27

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments.

  3. Effect of glucose and insulin on the expression of 1L-6 mRNA in 4T1 cells%葡萄糖和胰岛素对4T1肿瘤细胞IL-6mRNA表达的影响

    孙凤娥; 刘玉霞; 许郑林; 胡洁

    2011-01-01

    Objective To investigate the effect of glucose and insulin at different concentrations on the expression of IL-6 mRNA in 4T1 cells. Methods The 4T1 tumor cells were cultured in vitro,and according to the concentrations of glucose and insulin in culture medium,the cells were divided into 15 groups,with double-pored in each group. The cells were cultured for 48h in saturated humidity incubator,with 5% CO2 at 37℃. The expressions of IL-6 was detected by RT-PCR and the detection was repeated for three times. Results In group D and group E,the levels of IL-6 mRNA were signifieantly higher than those in group A. However there were no significant differences in the expression levels of IL-6 between group B, poup C and group A ( P > 0.05). As compared with group A, there was no statistical difference in the expression of IL-6 mRNA in 4T1 cells in group F, G, H, I and J. In group M, N, O, the levels of IL-6 mRNA were signitieantly higher than those of group A ( P < 0. 05 ). However there were no significant differences in the levels of IL-6 mRNA between group K,group L and group A ( P >0.05). Conclusion The high concentration of gluense can up-regulate the expression of IL-6 mRNA in 4T1 tumor cells, however,different concentrations of insulin have no effects on the expression of IL-6 mRNA in 4T1 tumor cells.%目的 研究不同浓度的葡萄糖和胰岛素对4T1肿瘤细胞IL-6 mRNA表达的影响.方法 体外常规培养4T1肿瘤细胞,根据所用培养液外加葡萄糖和胰岛素浓度的不同,将实验所用细胞分为15组.每组设双复孔,置37℃,5%CO2饱和湿度的培养箱培养48 h,收集细胞后抽提总RNA,RT-PCR同时扩增目的 片段IL-6和内参照β-actin,琼脂糖凝胶电泳,扩增产物在凝胶成像系统上扫描分析,计算IL-6 mRNA相对表达量.整个实验过程均重复3次.结果 D、E组IL-6 mRNA的表达高于A组(P<0.05);而B、C组IL-6 mRNA的表达与A组比较差异无统计学意义(P>0.05).F、G、H、I、J组4

  4. Design, optimization and characterization of the light concentrators of the single-mirror small size telescopes of the Cherenkov Telescope Array

    Aguilar, J A; Boccone, V; Cadoux, F; Christov, A; della Volpe, D; Montaruli, T; Platos, L; Rameez, M

    2014-01-01

    The focal-plane camera of $\\gamma$-ray telescopes frequently uses light concentrators in front of light sensors. The purpose of these concentrators is to increase the effective area of the camera as well as to reduce the stray light coming at large incident angles. These light concentrators are usually based on the Winston cone design. In this contribution we present the design of an hexagonal hollow light concentrator with a lateral profile optimized using a cubic B\\'ezier function to achieve a higher collection efficiency in the angular region of interest. The design presented here is optimized for a Davies-Cotton telescope with primary mirror of about 4 meters of diameter and focal length of 5.6 m. The described concentrators are part of an innovative camera made up of silicon-photomultipliers sensors, although a similar approach can be used for other sizes of single-mirror telescopes with different camera sensors, including photomultipliers. The challenge of our approach is to achieve a cost-effective des...

  5. Design, optimization and characterization of the light concentrators of the single-mirror small size telescopes of the Cherenkov Telescope Array

    Aguilar, J. A.; Basili, A.; Boccone, V.; Cadoux, F.; Christov, A.; della Volpe, D.; Montaruli, T.; Płatos, Ł.; Rameez, M.

    2015-01-01

    The focal-plane cameras of γ -ray telescopes frequently use light concentrators in front of the light sensors. The purpose of these concentrators is to increase the effective area of the camera as well as to reduce the stray light coming at large incident angles. These light concentrators are usually based on the Winston cone design. In this contribution we present the design of a hexagonal hollow light concentrator with a lateral profile optimized using a cubic Bézier function to achieve a higher collection efficiency in the angular region of interest. The design presented here is optimized for a Davies-Cotton telescope with a primary mirror of about 4 m in diameter and a focal length of 5.6 m. The described concentrators are part of an innovative camera made up of silicon-photomultiplier sensors, although a similar approach can be used for other sizes of single-mirror telescopes with different camera sensors, including photomultipliers. The challenge of our approach is to achieve a cost-effective design suitable for standard industrial production of both the plastic concentrator substrate and the reflective coating. At the same time we maximize the optical performance. In this paper we also describe the optical set-up to measure the absolute collection efficiency of the light concentrators and demonstrate our good understanding of the measured data using a professional ray-tracing simulation.

  6. Implementing a Description Grammar Interpreter: A Notation for Descriptions and Description Rules

    Stouffs, R.M.F.

    2015-01-01

    Description grammars represent a formalism for generating verbal descriptions of designs, used in conjunction with shape grammars. A description grammar constitutes a set of description rules that define a language of descriptions. A description grammar interpreter implements the mechanisms to inter

  7. Mirror illumination and spillover measurements of the Atacama Cosmology Telescope

    Gallardo, Patricio; Dünner, Rolando; Wollack, Edward; Henriquez, Fernando; Jerez-Hanckes, Carlos

    2012-09-01

    The Atacama Cosmology Telescope (ACT) is a 6 m telescope designed to map the Cosmic Microwave Background (CMB) simultaneously at 145 GHz, 220 GHz and 280GHz. The receiver in ACT, the Millimeter Bolometer Array Camera, features 1000 TES bolometers in each band. The detector performance depends critically on the total optical loading, requiring the spillover contributions from the optics to be minimal. This inspired the use of a cold Lyot stop to limit the illumination of the primary and the use of guard rings surrounding the primary and secondary reflectors. Here, we present a direct measurement of the illumination aperture for both reflectors and of the attenuation level outside the main optical path. We used a 145 GHz, 1mW source and a chopper wheel to produce a time-varying signal with a broad beam profile. We sampled the response of the camera for different locations of the source, placed in front and beside the primary and secondary mirrors. The aperture of the primary was measured to be 5.72 ± 0.17m in diameter (95 ± 3% of its geometrical size), while the aperture of the secondary yielded 2 ± 0.12m in diameter. Both apertures are consistent with the optical design. Comparing to previous measurements of the beam solid angle from planet observations, we estimate an optical efficiency of 72.3 ± 4.8%. We found that the attenuation outside the primary aperture was -16 ± 2 dB, which is below the theoretical expectations, and -22 ± 1 dB outside the secondary aperture, which is consistent with simulations. These results motivated the extension of the baffles surrounding the secondary mirror, with the following reduction in detector optical loading from 2.24pW to 1.88 pW.

  8. Mirror Illumination and Spillover Measurements of the Atacama Cosmology Telescope

    Gallardo, Patricio; Dunner, Rolando; Wollack, Ed; Jerez-Hanckes, Carlos

    2012-01-01

    The Atacama Cosmology Telescope (ACT) is a 6 m telescope designed to map the Cosmic Microwave Background (CMB) simultaneously at 145 GHz, 220GHz and 280GHz, The receiver in ACT, the Millimeter Bolometer Array Camera, features 1000 TES bolometers in each band, The detector performance depends critically on the total optical loading, requiring the spmover contributions from the optics to be minimal. This inspired the use of a cold Lyot stop to limit the illumination of the primary and the use of guard rings surrounding the primary and secondary reflectors. Here, we present a direct measurement of the illumination aperture for both reflectors and of the attenuation level outside the main optical path. We used a 145 GHz, 1 m W source and a chopper wheel to produce a time-varying signal with a broad heam proflle, We sampled the response of the camera for different locations of the source, placed in front and beside the primary and secondary mirrors. The aperture of the primary was measured to be 5,72 plus or minus 0,17m in diameter (95 plus or minus 3% of its geometrical size), while the aperture of the secondary yielded 2 plus or minus 0.12m in diameter. Both apertures are consistent with the optical design. Comparing to previous measurements of the beam solid angle from planet observations, we estimate an optical efficiency of 72.3 plus or minus 4,8%. We found that the attenuation outside the primary aperture was -16 plus or minus 2dB, which is below the theoretical expectations, and -22 plus or minus 1 dB outside the secondary aperture, which is consistent with simulations. These results motivated the extension of the baffles surrounding the secondary mirror, with the following reduction in detector optical loading from 2,24 pW to 188pW.

  9. Magnetic and electrical properties of flux grown single crystals of Ln6M4Al43 (Ln=Gd, Yb; M=Cr, Mo, W)

    Millimeter-sized single crystals of Ln6M4Al43 (Ln=Gd, Yb; M=Cr, Mo, W) were successfully grown with a molten aluminum flux. Synthetic conditions and physical properties for single crystals of all six analogs are discussed. The compounds exhibit metallic resistivity with room temperature values between 0.1 and 0.6 mΩ-cm. The Yb analogs are Pauli paramagnets with the Yb ion adopting the nonmagnetic divalent configuration (Yb2+). Gd6Cr4Al43, Gd6Mo4Al43, and Gd6W4Al43 appear to order antiferromagnetically at 19, 15, and 15 K, respectively. - Graphical abstract: The crystal structure of Yb6Cr4Al43. The light and dark green polyhedra show the chromium sublattice. Highlights: ► Single crystals up to 0.5 cm in length were grown with a molten aluminum flux. ► Physical property measurements were conducted on single crystals. ► Gadolinium analogs appear to order antiferromagnetically with positive θ. ► All analogs show metallic resistivity.

  10. Detection of Human Papilloma Virus Type 16 E6 mRNA in Laryngeal Squamous Cell Carcinoma by In Situ Hybridization

    Hai-rong Jiang; Peng Wang; Yong Li; Tao Ning; Xiao-song Rao; Bao-guoLiu

    2010-01-01

    Objective:Laryngeal squamous cell carcinoma(LSCC)is a common malignant tumor in Northeast China and is frequently associated with well-established risk factors like smoking and alcohol abuse.Human papilloma virus(HPV)is an epitheliotropic oncogenic virus that has been detected in a variety of head and neck tumors including LSCC.This retrospective study was to investigate the prevalence of HPV infection in patients with LSCC.Methods:In situ hybridization was performed in 99 patients with LSCC to detect the expression of HPV-16 E6mRNA.Results:The positive rate of HPV16 E6 mRNA was 36.36%(36/99)in laryngeal squamous cell carcinoma(LSCC),whereas only 3 of 50(6%)specimens of the normal laryngeal mucosa as a control group showed positive results(P0.05).Conclusion:The results suggest that the increased prevalence of HPV infection compared to normal laryngeal mucosa and the fact that high-risk HPV types(especially type 16)were the most frequently identified do not allow the exclusion of HPV as a risk factor in laryngeal squamous cell carcinoma.However,their clinical value remains to be further investigated.

  11. Detection of Human Papilloma Virus Type 16 E6 mRNA in Laryngeal Squamous Cell Carcinoma by In Situ Hybridization

    Hai-rong Jiang; Peng Wang; Yong Li; Tao Ning; Xiao-song Rao; Bao-guoLiu

    2011-01-01

    Objective: Laryngeal squamous cell carcinoma(LSCC) is a common malignant tumor in Northeast China and is frequently associated with well-established risk factors like smoking and alcohol abuse.Human papilloma virus (HPV) is an epitheliotropic oncogenic virus that has been detected in a variety of head and neck tumors including LSCC.This retrospective study was to investigate the prevalence of HPV infection in patients with LSCC.Methods: In situ hybridization was performed in 99 patients with LSCC to detect the expression of HPV-16 E6 mRNA.Results: The positive rate of HPV 16 E6 mRNA was 36.36%(36/99) in laryngeal squamous cell carcinoma (LSCC),whereas only 3 of 50(6%) specimens of the normal laryngeal mucosa as a control group showed positive results(P0.05).Conclusion: The results suggest that the increased prevalence of HPV infection compared to normal laryngeal mucosa and the fact that high-risk HPV types(especially type 16) were the most frequently identified do not allow the exclusion of HPV as a risk factor in laryngeal squamous cell carcinoma.However,their clinical value remains to be further investigated.

  12. In humans IL-6 is released from the brain during and after exercise and paralleled by enhanced IL-6 mRNA expression in the hippocampus of mice

    Rasmussen, P; Vedel, J-C; Olesen, J; Adser, Helle; Pedersen, M V; Hart, E; Secher, N H; Pilegaard, H

    2011-01-01

    Aim: Plasma interleukin-6 (IL-6) increases during exercise by release from active muscles and during prolonged exercise also from the brain. The IL-6 release from muscles continues into recovery and we tested whether the brain also releases IL-6 in recovery from prolonged exercise in humans....... Additionally, it was evaluated in mice whether brain release of IL-6 reflected enhanced IL-6 mRNA expression in the brain as modulated by brain glycogen levels. Methods: Nine healthy male subjects completed 4 h of ergometer rowing while the arterio-jugular venous difference (a-v diff) for IL-6 was determined....... The IL-6 mRNA and the glycogen content were determined in mouse hippocampus, cerebellum and cortex before and after 2 h treadmill running (N = 8). Results: At rest, the IL-6 a-v diff was negligible but decreased to -2.2 ± 1.9 pg ml(-1) at the end of exercise and remained low (-2.1 ± 2.1 pg ml(-1) ) 1...

  13. The AMANDA-II Neutrino-Telescope

    Wischnewski, R; collaboration, for the AMANDA

    2002-01-01

    The AMANDA-II telescope at the South Pole is constructed of 677 optical modules at 19 strings. We describe the observation of atmospheric neutrinos with the first stage 10-string detector AMANDA-B10, which establishes AMANDA as a working neutrino telescope. The expected performance for the AMANDA-II detector is discussed.

  14. Hard x-ray telescope mission

    Gorenstein, P.; Worrall, D.; Joensen, K.D.; Romaine, S.E.; Weisskopf, M.C.; Ramsey, B.D.; Bilbro, J.W.; Kroeger, R.A.; Gehrels, N.A.; Parsons, A.M.; Smither, R.K.; Christensen, Finn Erland; Citterio, O.; von Ballmoos, P.

    The Hard X-Ray Telescope was selected for study as a possible new intermediate size mission for the early 21st century. Its principal attributes are: (1) multiwavelength observing with a system of focussing telescopes that collectively observe from the UV to over 1 MeV, (2) much higher sensitivity...

  15. A Mechanical Analogue of the Refracting Telescope

    Vannoni, Maurizio; Molesini, Giuseppe; Sordini, Andrea; Straulino, Samuele

    2011-01-01

    The recent celebration of the discoveries made by Galileo four centuries ago has attracted new attention to the refracting telescope and to its use as an instrument for the observation of the night sky. This has offered the opportunity for addressing in the classroom the basic principles explaining the operation of the telescope. When doing so, a…

  16. Technology and the Hubble Space Telescope

    The components of the Hubble Space Telescope which is a 13.1 m long, 4.27 m in diameter, and weighs 11,000 kg are described. The telescope will be placed in a 600-km circular orbit of 28.5 deg inclination and it has an expected service life of 15 years. The optical telescope assembly contains the hyperbolic Ritchey-Chretin type primary and secondary mirrors and the optical control system. The telescope is to have a field of view of 28 arcmin in diameter. The use of the fine guidance sensors for pointing stability is examined. The optical and scientific system of the telescope are contained in the support system module. A wide-field/planetary camera, ESA-furnished faint object camera, the high-speed photometer, faint-object spectrograph, high resolution spectrograph, and ESA-furnished solar arrays are located on the telescope. The maintenance and refurbishment of the telescope are discussed. The precise lambda/20 optics, stringent cleanliness, and stable pointing of the telescope produce good image quality for astronomical and solar system science studies. 6 references

  17. Longer-Baseline Telescopes Using Quantum Repeaters

    Gottesman, Daniel; Jennewein, Thomas; Croke, Sarah

    2011-01-01

    We present an approach to building interferometric telescopes using ideas of quantum information. Current optical interferometers have limited baseline lengths, and thus limited resolution, because of noise and loss of signal due to the transmission of photons between the telescopes. The technology of quantum repeaters has the potential to eliminate this limit, allowing in principle interferometers with arbitrarily long baselines.

  18. CFRP lightweight structures for extremely large telescopes

    Jessen, Niels Christian; Nørgaard-Nielsen, Hans Ulrik; Schroll, J.

    2008-01-01

    Telescope structures are traditionally built out of steel. To improve the possibility of realizing the ambitious extremely large telescopes, materials with a higher specific stiffness and a lower coefficient of thermal expansion are needed. An important possibility is Carbon Fibre Reinforced Plas...

  19. A sensor architecture for neutrino telescopes

    In the Mediterranean Sea the ANTARES telescope is operating since 2006. Building on the success of this telescope and on the experiences of the DUMAND, IceCube, NEMO and NESTOR projects, a design for a new generation deep-sea neutrino telescope has been developed, which relies on the paradigm of the neutrino telescope as a giant sensor. Slender flexible strings with optical sensors form the basic building blocks for the telescope. The sensor concept has been implemented using photonic technologies for readout, data acquisition and communication, which allow for migration of functionalities from the deep-sea to the shore. This is one of the detector designs options developed during the EU funded KM3NeT Design Study. We will present its concept and implications for the detector as a whole.

  20. The Gemini 8-Meter Telescopes Project

    Boroson, Todd A.

    1995-05-01

    The Gemini 8-Meter Telescopes Project is an international partnership to build and operate two 8-meter telescopes, one on Mauna Kea, Hawaii, and one on Cerro Pachon, Chile. The telescopes will be international facilities, open to the scientific communities of the six member countries, the United States (50%), the United Kingdom (25%), Canada (15%), Chile (5%), Argentina (2.5%), and Brazil (2.5%). The telescopes are designed to exploit the best atmospheric conditions at these excellent sites. Near diffraction limited performance will be delivered at 2.2 microns and longward, with minimal degradation of the best seeing conditions at shorter wavelengths. The telescopes and facilities are designed to achieve emissivity division of the National Optical Astronomy Observatories. NOAO is operated by AURA, Inc. under cooperative agreement with the National Science Foundation.

  1. NLST: India's National Large Solar Telescope

    Hasan, S. S.; Soltau, D.; Kärcher, H.; Süß, M.; Berkefeld, T.

    2010-06-01

    This article introduces the new Indian 2 m telescope which has been designed by MT Mechatronics in a detailed conceptual design study for the Indian Institute of Astrophysics, Bangalore. We describe the background of the project and the science goals which shall be addressed with this telescope. NLST is a solar telescope with high optical throughput and will be equipped with an integrated Adaptive Optics system. It is optimized for a site with the kind of seeing and wind conditions as they are expected at a lake site in the Himalayan mountains. The telescope can also be used for certain night time applications. We also give the scientific rationale for this class of telescope.

  2. Calibration of the Cherenkov Telescope Array

    Gaug, Markus; Berge, David; Reyes, Raquel de los; Doro, Michele; Foerster, Andreas; Maccarone, Maria Concetta; Parsons, Dan; van Eldik, Christopher

    2015-01-01

    The construction of the Cherenkov Telescope Array is expected to start soon. We will present the baseline methods and their extensions currently foreseen to calibrate the observatory. These are bound to achieve the strong requirements on allowed systematic uncertainties for the reconstructed gamma-ray energy and flux scales, as well as on the pointing resolution, and on the overall duty cycle of the observatory. Onsite calibration activities are designed to include a robust and efficient calibration of the telescope cameras, and various methods and instruments to achieve calibration of the overall optical throughput of each telescope, leading to both inter-telescope calibration and an absolute calibration of the entire observatory. One important aspect of the onsite calibration is a correct understanding of the atmosphere above the telescopes, which constitutes the calorimeter of this detection technique. It is planned to be constantly monitored with state-of-the-art instruments to obtain a full molecular and...

  3. Monitoring LMXBs with the Faulkes Telescope

    Lewis, F; Fender, R P; Roche, P; Lewis, Fraser; Russell, David M.; Fender, Rob P.; Roche, Paul

    2006-01-01

    The Faulkes Telescope Project is the educational arm of the Las Cumbres Observatory Global Telescope Network (LCOGT). It currently has two 2-metre robotic telescopes, located at Haleakala on Maui (FT North) and Siding Spring in Australia (FT South). It is planned to increase this to six 2-metre telescopes in the future, complemented by a network of 30-40 smaller (0.4-1 metre) telescopes providing 24 hour coverage of both northern and southern hemispheres. We are undertaking a study of 10 low-mass X-ray binaries (LMXBs) using FT North to study the optical continuum behaviour of X-ray transients in quiescence. The introduction of FT South in September 2006 allows us to extend this monitoring to include 17 southern hemisphere LMXBs. With new instrumentation, we also intend to expand this monitoring to include both infrared wavelengths and spectroscopy.

  4. Layout design studies for medium-sized telescopes within the Cherenkov Telescope Array

    Hassan, T; Nieto, D; Wood, M

    2015-01-01

    The Cherenkov Telescope Array (CTA) is an international project for a next-generation ground-based gamma-ray observatory. CTA, conceived as an array of tens of imaging atmospheric Cherenkov telescopes, comprising small, medium and large-size telescopes, is aiming to improve on the sensitivity of current-generation experiments by an order of magnitude and provide energy coverage from 20 GeV to more than 300 TeV. In this study we explore how the medium-sized telescopes layout design and composition impacts the overall CTA performance by analyzing Monte Carlo simulations including Davies-Cotton and Schwarzschild-Couder medium-sized telescopes.

  5. Description of vegetation types

    US Fish and Wildlife Service, Department of the Interior — This document provides descriptions of five vegetation types found in Iowa- oak savannah, mature hardwoods, floodplain woods, scrub woods, and riparian woods. Oak...

  6. Hardware description languages

    Tucker, Jerry H.

    1994-01-01

    Hardware description languages are special purpose programming languages. They are primarily used to specify the behavior of digital systems and are rapidly replacing traditional digital system design techniques. This is because they allow the designer to concentrate on how the system should operate rather than on implementation details. Hardware description languages allow a digital system to be described with a wide range of abstraction, and they support top down design techniques. A key feature of any hardware description language environment is its ability to simulate the modeled system. The two most important hardware description languages are Verilog and VHDL. Verilog has been the dominant language for the design of application specific integrated circuits (ASIC's). However, VHDL is rapidly gaining in popularity.

  7. Monte Carlo Studies of medium-size telescope designs for the Cherenkov Telescope Array

    Wood, M; Dumm, J; Funk, S

    2015-01-01

    We present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parameters including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters repre...

  8. Upregulation of TNF-αand IL-6 mRNA in mouse liver induced by bacille Calmette-Guerin plus lipopolysaccharide

    Dao-fang LIU; Wei WEI; Li-hua SONG

    2006-01-01

    Aim:To investigate the mechanism of immunological liver injury induced by bacille Calmette-Guerin (BCG) plus lipopolysaccharide (LPS).Methods:Mice were injected via the tail vein with 125 mg/kg BCG,and 12 d later,the mice were injected intravenously with different doses of LPS (125,250.or 375 μg/kg).Serum alanine aminotransferase (ALT) activity and liver pathological changes were examined.The expression of tumor necrosis factor (TNF)-α,interleukin (IL)-6,lipopolysaccharide binding protein (LBP) and CD14 mRNA,and NF-κB and IκB-α protein in mouse liver at difierent time points after BCG and LPS injection were measured using RT-PCR,immunohistochemistry and Western blotting analysis,respectively.Results:The activity of serum ALT in mice treated witll BCG and LPS was significantly increased.Different degrees of liver injury,such as inflammatory cell infiltration,spotty necrosis,piecemeal necrosis,even bridging necrosis,could be seen in liver sections from mice after BCG and LPS administration.Furthermore,the levels of TNF-α and IL-6 mRNA in mouse liver were significantly elevated after administration of BCG plus LPS (P<0.05).The levels of LBP and CD14 mRNA in mouse liver were markedly upregulated after treatment with BCG and LPS.and treatment with BCG alone led to an increase in CD14 mRNA in mouse liver.Finally.immunoreactivity for NF-κB p65 was predominantly detected in hepatocyte nuclei from mice treated with BCG plus LPS,compared with the normal group.Protein levels of IκB-α were strikingly decreased by LPS or BCG plus LPS treatment.compared with the normal group or BCG group.Conclusion:TNF-α and IL-6 mRNA were partially involved in early immunological liver injury induced by chal lenge with small doses of LPS after BCG priming.Upregulation of TNF-α and IL6 mRNA might be related to increases in LBP and CD14 mRNA expression and activation of NF-kB.Furthermore,BCG priming in immunological liver injury may occur via upregulation of CD14 mRNA expression in

  9. Structural, electronic and magnetic properties of Mo (4d)-based complex perovskites Ba{sub 2}MMoO{sub 6} (M=Cr and Fe)

    Musa Saad H E, M., E-mail: musa.1964@gmail.com [Department of Physics, College of Science, Qassim University, Buridah 51452 (Saudi Arabia); El-Hagary, M. [Physics Department, Faculty of Science, Helwan University, Helwan, Cairo (Egypt); Institut für Festkörperphysik, TU Wien, A-1040 Wien (Austria)

    2014-06-01

    We report a study of crystallographic parameters of the Mo-based complex perovskites Ba{sub 2}MMoO{sub 6} (M=Cr and Fe) obtained from analysis of X-ray diffraction (XRD) data and the electronic and magnetic properties prediction using the magnetic measurements and the full-potential linearized muffin–tin orbitals within the plane-wave approximation (LMTO–PLW). The Ba{sub 2}MMoO{sub 6} materials were prepared by the solid state reaction method. XRD analysis reveals that Ba{sub 2}MMoO{sub 6} crystalline in a cubic structure (space group Fm-3m) with lattice parameters (a=8.013 Å) for M=Cr and (a=8.061 Å) for M=Fe. XRD results present a matching of 98% with the theoretical results. The densities of states were calculated using the local spin density approximation (LSDA) and LSDA+U methods. LDOS results show a half-metallic-ferrimagnetic ground state for Ba{sub 2}MMoO{sub 6}, which is in majority due to the 4d-t{sub 2g} and 3d-t{sub 2g} characters. The structural, electronic and magnetic calculation results are in excellent agreement with the experimental and previous theoretical results. - Highlights: • Mo-based complex perovskites Ba{sub 2}MMoO{sub 6} (M=Cr and Fe) have been studied. • XRD analysis revealed Ba{sub 2}MMoO{sub 6} crystalline in cubic structures (Fm-3m). • Full-potential linear muffin–tin orbital (LMTO) calculations have been carried out. • The DOSs were calculated using the LSDA and correlated LSDA+U methods. • Ba{sub 2}MMoO{sub 6} (M=Cr and Fe) shows HM–FiM nature due to 3d-t{sub 2g}–4d-t{sub 2g} characters.

  10. Schwarzschild-Couder two-mirror telescope for ground-based gamma-ray astronomy

    Vasilev, V V

    2007-01-01

    Schwarzschild-type aplanatic telescopes with two aspheric mirrors, configured to correct spherical and coma aberrations, are considered for application in gamma-ray astronomy utilizing the ground-based atmospheric Cherenkov technique. We use analytical descriptions for the figures of primary and secondary mirrors and, by means of numerical ray-tracing, we find telescope configurations which minimize astigmatism and maximize effective light collecting area. It is shown that unlike the traditional prime-focus Davies-Cotton design, such telescopes provide a solution for wide field of view gamma-ray observations. The designs are isochronous, can be optimized to have no vignetting across the field, and allow for significant reduction of the plate scale, making them compatible with finely-pixilated cameras, which can be constructed from modern, cost-effective image sensors such as multi-anode PMTs, SiPMs, or image intensifiers.

  11. Self-organized criticality properties of the turbulence-induced particle flux at the plasma edge of the HT-6M tokamak

    The power spectrum and the probability distribution function (PDF) of the turbulence-induced particle flux Γ in the velocity shear layer of the HT-6M edge region have been measured and analysed. Three regions of frequency dependence (f0, f-1, f-4) have been observed in the spectrum of the flux. The PDF of the flux displays a Γ-1 scaling over one decade in Γ. Using the rescaled-range statistical technique, the authors find that the degree of the self-similarity (Hurst exponent) of the particle flux in the measured region ranges from 0.64 to 0.83. All of these results may mean that the plasma transport is in a state characterized by self-organized criticality

  12. Partial Replacement of the 6 m Coke oven Column%6米焦炉焦侧炉柱局部更换实践

    郭涛

    2015-01-01

    结合山钢股份莱芜分公司焦化厂5#、6#焦炉104#焦侧炉柱变形情况的测量分析,介绍了6米焦炉焦侧炉柱局部更换过程,为类似作业提供经验。%According to the measurement analysis of deformation of the coke column of NO .104 coking chamber of NO .5/NO.6 coke oven in coking plant of Shandong Iron and Steel Ltd .Laiwu Branch, we introduce how to replace the part of the 6m coke oven’s column.This thesis provides valuable experience for the future similar works .

  13. A 3-10 GHz IR-UWB CMOS Pulse Generator With 6-mW Peak Power Dissipation Using A Slow-Charge Fast-Discharge Technique

    Shen, Ming; Yin, Ying-Zheng; Jiang, Hao;

    2014-01-01

    This letter proposes a UWB pulse generator topology featuring low peak power dissipation for applications with stringent instantaneous power requirements. This is accomplished by employing a new slow-charge fast-discharge approach to extend the time duration of the generator's peak current so that...... of 1 Gpps, a minimum peak power consumption of 6 mW, and a low energy consumption of 5 pJ/pulse. The fabricated pulse generator measures 0.16 mm2....... the peak value of the current is significantly reduced, while maintaining the waveform of the generated UWB pulse signal. A prototype pulse generator has been implemented using the UMC 0.18 μm CMOS process for validation. The pulse generator offers a 3-10 GHz bandwidth, a maximum pulse repetitive rate...

  14. Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO4 at 303 K

    This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pCH values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

  15. Optical Testing and Verification Methods for the James Webb Space Telescope Integrated Science Instrument Module Element

    Antonille, Scott R.; Miskey, Cherie L.; Ohl, Raymond G.; Rohrbach, Scott O.; Aronstein, David L.; Bartoszyk, Andrew E.; Bowers, Charles W.; Cofie, Emmanuel; Collins, Nicholas R.; Comber, Brian J.; Eichhorn, William L.; Glasse, Alistair C.; Gracey, Renee; Hartig, George F.; Howard, Joseph M.; Kelly, Douglas M.; Kimble, Randy A.; Kirk, Jeffrey R.; Kubalak, David A.; Landsman, Wayne B.; Lindler, Don J.; Malumuth, Eliot M.; Maszkiewicz, Michael; Rieke, Marcia J.; Rowlands, Neil; Sabatke, Derek S.; Smith, Corbett T.; Smith, J. Scott; Sullivan, Joseph F.; Telfer, Randal C.; Plate, Maurice Te; Vila, M. Begona; Warner, Gerry D.; Wright, Raymond H.; Wright, David; Zhou, Julia; Zielinski, Thomas P.

    2016-01-01

    NASA's James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (40K). The JWST Observatory includes the Optical Telescope Element (OTE) and the Integrated Science Instrument Module (ISIM) that contains four science instruments (SI) and the fine guider. The SIs are mounted to a composite metering structure. The SI and guider units were integrated to the ISIM structure and optically tested at the NASA Goddard Space Flight Center as a suite using the Optical Telescope Element SIMulator (OSIM). OSIM is a full field, cryogenic JWST telescope simulator. SI performance, including alignment and wave front error, were evaluated using OSIM. We describe test and analysis methods for optical performance verification of the ISIM Element, with an emphasis on the processes used to plan and execute the test. The complexity of ISIM and OSIM drove us to develop a software tool for test planning that allows for configuration control of observations, associated scripts, and management of hardware and software limits and constraints, as well as tools for rapid data evaluation, and flexible re-planning in response to the unexpected. As examples of our test and analysis approach, we discuss how factors such as the ground test thermal environment are compensated in alignment. We describe how these innovative methods for test planning and execution and post-test analysis were instrumental in the verification program for the ISIM element, with enough information to allow the reader to consider these innovations and lessons learned in this successful effort in their future testing for other programs.

  16. ALMA Telescope Reaches New Heights

    2009-09-01

    ball at a distance of nine miles, and to keep their smooth reflecting surfaces accurate to less than the thickness of a human hair. Once the transporter reached the high plateau it carried the antenna to a concrete pad -- a docking station with connections for power and fiber optics -- and positioned it with an accuracy of a small fraction of an inch. The transporter is guided by a laser steering system and, just like some cars, also has ultrasonic collision detectors. These sensors ensure the safety of the state-of-the-art antennas as the transporter drives them across what will soon be a rather crowded plateau. Ultimately, ALMA will have at least 66 antennas distributed over about 200 pads, spread over distances of up to 11.5 miles and operating as a single, giant telescope. Even when ALMA is fully operational, the transporters will be used to move the antennas between pads to reconfigure the telescope for different kinds of observations. This first ALMA antenna at the high site will soon be joined by others, and the ALMA team looks forward to making their first observations from the Chajnantor plateau. They plan to link three antennas by early 2010, and to make the first scientific observations with ALMA in the second half of 2011. ALMA will help astronomers answer important questions about our cosmic origins. The telescope will observe the Universe using light with millimeter and submillimeter wavelengths, between infrared light and radio waves in the electromagnetic spectrum. Light at these wavelengths comes from some of the coldest, and from some of the most distant objects in the cosmos. These include cold clouds of gas and dust where new stars are being born, or remote galaxies towards the edge of the observable universe. The Universe is relatively unexplored at submillimeter wavelengths, as the telescopes need extremely dry atmospheric conditions, such as those at Chajnantor, and advanced detector technology. The Atacama Large Millimeter/submillimeter Array

  17. Proposed National Large Solar Telescope

    Jagdev Singh

    2008-03-01

    Sun’s atmosphere is an ideal place to study and test many magnetohydrodynamic (MHD) processes controlling turbulent plasma. We wish to resolve some of the finest solar features (which remain unresolved presently) and study their dynamics. Indian Institute of Astrophysics has proposed to design, fabricate and install a 2-meter class solar telescope at a suitable site in India to resolve features on the Sun of the size of about 0.1 arcsec. The focal plane instruments will include a high resolution polarimeteric package to measure polarization with an accuracy of 0.01 per cent; a high spectral resolution spectrograph to obtain spectra in 5 widely separated absorption lines simultaneously and high spatial resolution narrow band imagers in various lines. The Himalayan region appears to be a good choice keeping in view the prevailing dry and clear weather conditions. We have started detailed analysis of the weather conditions in the area and at some other locations in India. The site characterization will be done using the Sun-photometer, S-DIMM and SHABAR techniques to determine the seeing conditions.

  18. Seismic analysis of the LSST telescope

    Neill, Douglas R.

    2012-09-01

    The Large Synoptic Survey Telescope (LSST) will be located on the seismically active Chilean mountain of Cerro Pachón. The accelerations resulting from seismic events produce the most demanding load cases the telescope and its components must withstand. Seismic ground accelerations were applied to a comprehensive finite element analysis (FEA) model which included the telescope, its pier and the mountain top. Response accelerations for specific critical components (camera and secondary mirror assembly) on the telescope were determined by applying seismic accelerations in the form of Power Spectral Densities (PSD) to the FEA model. The PSDs were chosen based on the components design lives. Survival level accelerations were determined utilizing PSDs for seismic events with return periods 10 times the telescope's design life which is equivalent to a 10% chance of occurring over the lifetime. Since the telescope has a design life of 30 years it was analyzed for a return period of 300 years. Operational level seismic accelerations were determined using return periods of 5 times the lifetimes. Since the seismic accelerations provided by the Chilean design codes were provided in the form of Peak Spectral Accelerations (PSA), a method to convert between the two forms was developed. The accelerations are also affected by damping level. The LSST incorporates added damping to meets its rapid slew and settle requirements. This added damping also reduces the components' seismic accelerations. The analysis was repeated for the telescope horizon and zenith pointing. Closed form solutions were utilized to verify the results.

  19. Thermal investigation of a large lunar telescope

    Walker, Sherry T.

    1992-01-01

    Recent interest in construction of a large telescope on the lunar surface (Nein and Davis, 1991; Bely, Burrows, and Illingworth, 1989) has prompted this feasibility study of a thermal control system for a 16 meter diameter telescope located near the lunar equator. In addition to detailed analyses for a telescope located in a flat area near the equator, the thermal effect of locating the telescope in a crater, on a hill, and at higher latitude sites is discussed. Because an unprotected telescope experiences a wide range of temperature swings, several thermal protection schemes have been examined, including domes, sunshades, and ground shields to limit the temperature excursions of the primary mirror. Results of these analyses indicate that mirror temperature excursions can be limited to less than 100 Kelvin (K) per lunar cycle with an appropriate passive thermal protection system (dome), and that the telescope primary mirror can be maintained at less than 100 K for at least 7 days of each lunar cycle. However, such a dome precludes observations during the lunar day. Mirror temperature excursions can be reduced by incorporating thermal enclosures or shades in the design or by placing the telescope at a higher latitude.

  20. Parametric Cost Models for Space Telescopes

    Stahl, H. Philip; Henrichs, Todd; Dollinger, Courtney

    2010-01-01

    Multivariable parametric cost models for space telescopes provide several benefits to designers and space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there is no definitive space telescope cost model. In fact, published models vary greatly [1]. Thus, there is a need for parametric space telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric space telescope cost models based on the latest available data and applying rigorous analytical techniques. Specific cost estimating relationships (CERs) have been developed which show that aperture diameter is the primary cost driver for large space telescopes; technology development as a function of time reduces cost at the rate of 50% per 17 years; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and increasing mass reduces cost.

  1. Optoelectronic behavior of Quaternary Uranium Chalcogenides Rb{sub 2}Pd{sub 3}UM{sub 6} (M = S, Se): A first principle study

    Din, Haleem Ud [Department of Physics, Hazara University, Mansehra (Pakistan); Azam, Sikander; Khan, Saleem Ayaz [New Technologies – Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique et de Modélisation Mathématique (LPQ3M), Département de Technologie, Université de Mascara, Mascara 29000 (Algeria)

    2014-12-05

    Highlights: • The Fermi surface and optoelectronic properties for Rb{sub 2}Pd{sub 3}UM{sub 6} (M = S, Se) compounds are investigated for the first time. • The electronic band structure calculations reveal a metallic nature for the herein studied compounds. • The bonding nature between different atoms is discussed. • Considerable anisotropy was found between the principal complex tensor components for the two compounds. - Abstract: First principle calculations of electronic, Fermi surface, electronic charge density and optical properties of Quaternary Uranium Chalcogenides Rb{sub 2}Pd{sub 3}UM{sub 6} (M = S, Se) are performed using full potential linear augmented plane wave (FP-LAPW) method within the frame work of density functional theory. Using mBJ method, the electronic band curves overlap at Fermi level and show metallic band structure for both compounds. The calculated densities of states (DOS) spectra show that the valence band is mainly attributed to Rb-p, Pd-d and S-s/p or Se-s/p states; conduction band is mainly attributed to Pd-d, U-f and S-p or Se-p/d states. From the electronic charge density spectrum, it is revealed that a strong covalent bond exists between Pd and S, and Pd or Se while charge transfer between U and S, U and Se, Rb and S, and Rb and Se atoms results in ionic bond nature. It is noted from Fermi surface calculations that both compounds comprise same number of fast velocity electrons but differs in slow or intermediate velocity of electrons. The calculated frequency dependent dielectric function, energy loss function and reflectivity show a considerable anisotropy for both compounds.

  2. Implication of Xenobiotic Metabolizing Enzyme gene (CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 Polymorphisms in Breast Carcinoma

    Gabbouj Sallouha

    2008-04-01

    Full Text Available Abstract Background Xenobiotic Metabolizing Enzymes (XMEs contribute to the detoxification of numerous cancer therapy-induced products. This study investigated the susceptibility and prognostic implications of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene polymorphisms in breast carcinoma patients. Methods The authors used polymerase chain reaction and restriction enzyme digestion to characterize the variation of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene in a total of 560 unrelated subjects (246 controls and 314 patients. Results The mEH (C/C mutant and the NAT2 slow acetylator genotypes were significantly associated with breast carcinoma risk (p = 0.02; p = 0.01, respectively. For NAT2 the association was more pronounced among postmenopausal patients (p = 0.006. A significant association was found between CYP2D6 (G/G wild type and breast carcinoma risk only in postmenopausal patients (p = 0.04. Association studies of genetic markers with the rates of breast carcinoma specific overall survival (OVS and the disease-free survival (DFS revealed among all breast carcinoma patients no association to DFS but significant differences in OVS only with the mEH gene polymorphisms (p = 0.02. In addition, the mEH wild genotype showed a significant association with decreased OVS in patients with axillary lymph node-negative patients (p = 0.03 and with decreasesd DFS in patients with axillary lymph node-positive patients (p = 0.001. However, the NAT2 intermediate acetylator genotype was associated with decreased DFS in axillary lymph node-negative patients. Conclusion The present study may prove that polymorphisms of some XME genes may predict the onset of breast carcinoma as well as survival after treatment.

  3. Structural, electronic, and magnetic properties of double perovskite Pb2CrMO6 (M=Mo, W and Re) from first-principles investigation

    We use first-principles methods to study double perovskite Pb2CrMO6 (M: some 4d and 5d transition metals), and find that a magnetic I4/m structure is lowest in total energy per formula unit for M=Mo, W, and Re. Our electronic structure investigation shows that the three double perovskite compounds are half-metallic ferrimagnets with total magnetic moments of 2μB, 2μB and 1μB per formula unit, respectively. With the spin–orbit coupling included, our calculations show the high magnetocrystalline anisotropy (MCA) in Pb2CrReO6. Fortunately, the spin polarization of Pb2CrMO6 at the Fermi level remains 90% ∼99%. The orbital moments of 3d Cr and 4d Mo are small, but the 5d ions of W and Re have large unquenched orbital moments, which can be attributed stronger spin–orbit coupling in the 5d orbitals than in 3d/4d ones. In addition, these results are confirmed by using improved exchange–correlation functionals. Furthermore, we calculate the spin exchange constants of the three Pb2CrMO6, and our Monte Carlo simulated Curie temperatures for them are at least 480 K. These materials, when synthesized, should be useful in spintronics. - Highlights: • Our first-principles calculation show that a magnetic I4/m structure is lowest in total energy per formula unit for Pb2CrMO6 (M=Mo, W, and Re). • With spin–orbit coupling included, the spin polarization of Pb2CrMO6 at the Fermi level remains 90%–99%. • The simulated Curie temperature (Tc) values by Monte Carlo method are at least 480 K, which is favorable for potential spintronic applications

  4. Ground-Based Telescope Parametric Cost Model

    Stahl, H. Philip; Rowell, Ginger Holmes

    2004-01-01

    A parametric cost model for ground-based telescopes is developed using multi-variable statistical analysis, The model includes both engineering and performance parameters. While diameter continues to be the dominant cost driver, other significant factors include primary mirror radius of curvature and diffraction limited wavelength. The model includes an explicit factor for primary mirror segmentation and/or duplication (i.e.. multi-telescope phased-array systems). Additionally, single variable models based on aperture diameter are derived. This analysis indicates that recent mirror technology advances have indeed reduced the historical telescope cost curve.

  5. Development of an X-ray Telescope with a Large Effective Area for the Iron K Line Band

    Matsumoto, Hironori; Tachibana, Sasagu; Yoshikawa, Shun; Tamura, Keisuke; Mori, Hideyuki; Mitsuishi, Ikuyuki; Tawara, Yuzuru; Kunieda, Hideyo; Yamashita, Kojun

    2015-08-01

    X-ray micro-calorimeters such as the Soft X-ray Spectrometer (SXS) on board ASTRO-H will enable precise spectroscopy of iron K lines even for spatially extended objects. To exploit the full power of the high-energy resolution, X-ray telescopes with a large effective area around 6 keV are essentially important. Conventional Wolter-I X-ray telescopes aimed at X-rays below 10 keV have used the principle of total reflection to collect the X-rays. Enlarging the diameter of this type of telescopes is not effective to obtain the large effective area, since the incident angle of X-rays for the outer part of the telescope exceeds the critical angle, and the X-ray reflectivity of the outer part is significantly low. For example, the critical angle of Ir for an X-ray of 6 keV is 0.748 deg. Thus if we assume a focal length of 6 m for a Wolter-I optics using mirrors covered with Ir as a reflector, the mirrors the radial position of which are larger than 34 cm cannot reflect X-rays above 6 keV effectively. If multi-layer mirrors are applied to the outer part of the telescope, however, the X-ray reflectivity can be enhanced significantly by the principle of Bragg reflection. Our objective is to develop a Wolter-I X-ray telescope with an aperture of 110 cm and a focal length of 6 m, and make all mirrors in the telescope can reflect X-rays around 6 keV effectively by utilizing the multi-layer mirrors. The size of the telescope is determined by a boundary condition that can be launched by the epsilon rocket of ISAS/JAXA. The multi-layer is designed to enhance the reflectivity at 6.4 keV, 6.7 keV, or 6.9 keV. Our simulation suggests that the effective area averaged in the 5.7-7.7 keV band could be 2000 cm2, whichis comparable to the effective area of Athena launched in 2028 by ESA. Furthermore, we showed that the Ir/C multi-layers produced by our DC magnetron sputtering machine has a surface roughness of less than 4 angstrom. This value is smaller than the average surface roughness

  6. Flavor distribution of UHE cosmic neutrino oscillations at neutrino telescopes

    Xing, Zhi-Zhong

    2009-04-01

    If the ultrahigh-energy (UHE) cosmic neutrinos produced from a distant astrophysical source can be measured at a km-size neutrino telescope such as the IceCube or KM3NeT, they will open a new window to understand the nature of flavor mixing and to probe possible new physics. Considering the conventional UHE cosmic neutrino source with the flavor ratio φe:φμ:φτ=1:2:0, I point out two sets of conditions for the flavor democracy φeT:φμT:φτT=1:1:1 to show up at neutrino telescopes: either θ13=0 and θ23=π/4 (CP invariance) or δ=±π/2 and θ23=π/4 (CP violation) in the standard parametrization of the 3×3 neutrino mixing matrix V. Allowing for slight μ-τ symmetry breaking effects characterized by Δ∈[-0.1,+0.1], I find φeT:φμT:φτT=(1-2Δ):(1+Δ):(1+Δ) as a good approximation. Another possibility to constrain Δ is to detect the ν flux of E≈6.3PeV via the Glashow resonance channel νe→W→anything. I also give some brief comments on (1) possible non-unitarity of V in the seesaw framework and its effects on the flavor distribution at neutrino telescopes and (2) a generic description and determination of the cosmic neutrino flavor composition at distant astrophysical sources.

  7. The Zadko Telescope: the Australian Node of a Global Network of Fully Robotic Follow-up Telescopes

    Coward, David,; Laas-Bourez, Myrtille; Todd, Michael

    2010-01-01

    The Zadko Telescope (ZT) - see Coward et al. (2010), is a purpose built 1 meter, robotic telescope, located about 80 km north of Perth, Western Australia. It was designed to monitor a previously unchartered region of the "transient sky". The Zadko Telescope is the only meter class telescope capable of deep imaging between the east coast of Australia and South Africa at similar latitude. The Zadko Telescope, operated by UWA, is the Australian "node" of the TAROT robotic telescope network. As t...

  8. The MAGIC telescope project for gamma ray astronomy in the 15 to 300 GeV energy range

    In gamma ray astronomy the energy range between 15 and 300 GeV is up to now inaccessible for both satellite borne γ detectors and ground based air Cherenkov telescopes. It is expected that in this energy range the universe is highly transparent and sources such as active galactic nuclei at red shifts of up to ∝2.8 can be observed. The detection of gamma ray bursts would allow one to place a limit on their distance. A short description of a project to build a new, high sensitivity, 17 m, air Cherenkov telescope, dubbed the MAGIC telescope, and an overview of its physics potential will be given. The telescope is based upon a 17 m decommissioned solar concentrator. (orig.)

  9. Observations of SN 1987A at the Anglo-Australian Telescope

    Since outburst, about 15% of all time on the 3.9 m Anglo-Australian telescope (AAT) has been devoted to observing SN 1987A. In this report the author describes these observations, first discussing the policy and organization adopted for making them followed by a description of the various types of observation made. The author presents some of the highlights which have emerged from these observations

  10. Testing and data reduction of the Chinese Small Telescope Array (CSTAR) for Dome A, Antarctica

    The Chinese Small Telescope Array (CSTAR) is the first Chinese astronomical instrument on the Antarctic ice cap. The low temperature and low pressure testing of the data acquisition system was carried out in a laboratory refrigerator and on the 4500 m Pamirs high plateau, respectively. The results from the final four nights of test observations demonstrated that CSTAR was ready for operation at Dome A, Antarctica. In this paper, we present a description of CSTAR and the performance derived from the test observations.

  11. Career Path Descriptions

    Charkiewicz, A

    2000-01-01

    Before the Career Path system, jobs were classified according to grades with general statutory definitions, guided by the "Job Catalogue" which defined 6 evaluation criteria with example illustrations in the form of "typical" job descriptions. Career Paths were given concise statutory definitions necessitating a method of description and evaluation adapted to their new wider-band salary concept. Evaluations were derived from the same 6 criteria but the typical descriptions became unusable. In 1999, a sub-group of the Standing Concertation Committee proposed a new guide for describing Career Paths, adapted to their wider career concept by expanding the 6 evaluation criteria into 9. For each criterion several levels were established tracing the expected evolution of job level profiles and personal competencies over their longer salary ranges. While providing more transparency to supervisors and staff, the Guide's official use would be by services responsible for vacancy notices, Career Path evaluations and rela...

  12. Cosmology with liquid mirror telescopes

    Hogg, David W.; Gibson, Brad K.; Hickson, Paul

    1993-01-01

    Liquid mirrors provide an exciting means to obtain large optical telescopes for substantially lower costs than conventional technologies. The liquid mirror concept has been demonstrated in the lab with the construction of a diffraction limited 1.5 m mirror. The mirror surface, using liquid mercury, forms a perfect parabolic shape when the mirror cell is rotated at a uniform velocity. A liquid mirror must be able to support a heavy mercury load with minimal flexure and have a fundamental resonant frequency that is as high as possible, to suppress the amplitude of surface waves caused by small vibrations transmitted to the mirror. To minimize the transmission of vibrations to the liquid surface, the entire mirror rests on an air bearing. This necessitates the mirror cell being lightweight, due to the limited load capabilities of the air bearing. The mirror components must also have physical characteristics which minimize the effects of thermal expansion with ambient temperature fluctuations in the observatory. In addition, the 2.7 m mirror construction is designed so that the techniques used may be readily extended to the construction of large mirrors. To attain the goals of a lightweight, rigid mirror, a composite laminant construction was used. The mirror consists of a foam core cut to the desired parabolic shape, with an accuracy of a few mm. An aluminum hub serves as an anchor for the foam and skin, and allows precise centering of the mirror on the air bearing and drive system. Several plys of Kevlar, covered in an epoxy matrix, are then applied to the foam. A final layer of pure epoxy is formed by spin casting. This final layer is parabolic to within a fraction of a mm. An aluminum ring bonded to the circumference of the mirror retains the mercury, and incorporates stainless-steel hard-points for the attachment of balance weights.

  13. The Telescope Array Middle Drum fluorescence detector simulation on GPUs

    In recent years, the Graphics Processing Unit (GPU) has been recognized and widely used as an accelerator for many scientific calculations. In general, problems amenable to parallelization are ones that benefit most from the use of GPUs. The Monte Carlo simulation of fluorescence detector response to air showers presents many opportunities for parallelization. In this paper we report on a Monte Carlo program used for the simulation of the Telescope Array Fluorescence Detector located at the Middle Drum site which uses GPU acceleration. All of the physics simulation from shower development, light production and atmospheric attenuation, as well as, the realistic detector optics and electronics simulations are done on the GPU. A detailed description of the code implementation is given, and results on the accuracy and performance of the simulation are presented as well. Improvements in computational throughput in excess of 50× are reported and the accuracy of the results is on par with the CPU implementation of the simulation.

  14. Design constraints on Cherenkov telescopes with Davies-Cotton reflectors

    Bretz, Thomas

    2013-01-01

    This paper discusses the construction of high-performance ground-based gamma-ray Cherenkov telescopes with a Davies-Cotton reflector. For the design of such telescopes, usually physics constrains the field-of-view, while the photo-sensor size is defined by limited options. Including the effect of light-concentrators in front of the photo sensor, it is demonstrated that these constraints are enough to mutually constrain all other design parameters. The dependability of the various design parameters naturally arises once a relationship between the value of the point-spread functions at the edge of the field-of-view and the pixel field-of-view is introduced. To be able to include this constraint into a system of equations, an analytical description for the point-spread function of a tessellated Davies-Cotton reflector is derived from Taylor developments and ray-tracing simulations. Including higher order terms renders the result precise on the percent level. Design curves are provided within the typical phase sp...

  15. The Atacama Cosmology Telescope: Data Characterization and Map Making

    Dünner, Rolando; Marriage, Tobias A; Sievers, Jon; Acquaviva, Viviana; Addison, Graeme E; Ade, Peter A R; Aguirre, Paula; Amiri, Mandana; Appel, John William; Barrientos, L Felipe; Battistelli, Elia S; Bond, J Richard; Brown, Ben; Burger, Bryce; Calabarese, Erminia; Chervenak, Jay; Das, Sudeep; Devlin, Mark J; Dicker, Simon R; Doriese, W Bertrand; Dunkley, Joanna; Essinger-Hileman, Thomas; Fisher, Ryan P; Gralla, Megan B; Fowler, Joseph W; Hajian, Amir; Halpern, Mark; Hernández-Monteagudo, Carlos; Hilton, Gene C; Hilton, Matt; Hincks, Adam D; Hlozek, Renée; Huffenberger, Kevin M; Hughes, David H; Hughes, John P; Infante, Leopoldo; Irwin, Kent D; Juin, Jean Baptiste; Kaul, Madhuri; Klein, Jeff; Kosowsky, Arthur; Lau, Judy M; Limon, Michele; Lin, Yen-Ting; Louis, Thibaut; Lupton, Robert H; Marsden, Danica; Martocci, Krista; Mauskopf, Phil; Menanteau, Felipe; Moodley, Kavilan; Moseley, Harvey; Netterfield, Calvin B; Niemack, Michael D; Nolta, Michael R; Page, Lyman A; Parker, Lucas; Partridge, Bruce; Quintana, Hernán; Reid, Beth; Sehgal, Neelima; Sherwin, Blake D; Spergel, David N; Staggs, Suzanne T; Swetz, Daniel S; Switzer, Eric R; Thornton, Robert; Trac, Hy; Tucker, Carole; Warne, Ryan; Wilson, Grant; Wollack, Ed; Zhao, Yue

    2012-01-01

    We present a description of the data reduction and mapmaking pipeline used for the 2008 observing season of the Atacama Cosmology Telescope (ACT). The data presented here at 148 GHz represent 12% of the 90 TB collected by ACT from 2007 to 2010. In 2008 we observed for 136 days, producing a total of 1423 hours of data (11 TB for the 148 GHz band only), with a daily average of 10.5 hours of observation. From these, 1085 hours were devoted to a 850 deg^2 stripe (11.2 hours by 9.1 deg) centered on a declination of -52.7 deg, while 175 hours were devoted to a 280 deg^2 stripe (4.5 hours by 4.8 deg) centered at the celestial equator. We discuss sources of statistical and systematic noise, calibration, telescope pointing, and data selection. Out of 1260 survey hours and 1024 detectors per array, 816 hours and 593 effective detectors remain after data selection for this frequency band, yielding a 38% survey efficiency. The total sensitivity in 2008, determined from the noise level between 5 Hz and 20 Hz in the time-o...

  16. Introduction to the Solar Space Telescope

    G. Ai; S. Jin; S. Wang; B. Ye; S. Yang

    2000-09-01

    The design of the space solar telescope (SST) (phase B) has been completed. The manufacturing is under development. At the end of 2000, it will be assembled. The basic aspect will be introduced in this paper.

  17. W.M. Keck Telescope control system

    Lupton, William; Lewis, Hilton; Honey, Allan

    1994-06-01

    The computing environment and major components of the Keck telescope control system are discussed. This is followed by a discussion of calibration procedures and a review of current status and problems.

  18. Lightweight composite mirrors for telescopes Project

    National Aeronautics and Space Administration — Lightweight, steady and stiff mirrors are necessary to decrease cost of telescopes such as IXO and GenX used in special NASA missions. Low-density materials are...

  19. Wide-Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets coronagraphic operations: lessons learned from the Hubble Space Telescope and the James Webb Space Telescope

    Debes, John H.; Ygouf, Marie; Choquet, Elodie; Hines, Dean C.; Perrin, Marshall D.; Golimowski, David A.; Lajoie, Charles-Phillipe; Mazoyer, Johan; Pueyo, Laurent; Soummer, Rémi; van der Marel, Roeland

    2016-01-01

    The coronagraphic instrument (CGI) currently proposed for the Wide-Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets (WFIRST-AFTA) mission will be the first example of a space-based coronagraph optimized for extremely high contrasts that are required for the direct imaging of exoplanets reflecting the light of their host star. While the design of this instrument is still in progress, this early stage of development is a particularly beneficial time to consider the operation of such an instrument. We review current or planned operations on the Hubble Space Telescope and the James Webb Space Telescope with a focus on which operational aspects will have relevance to the planned WFIRST-AFTA CGI. We identify five key aspects of operations that will require attention: (1) detector health and evolution, (2) wavefront control, (3) observing strategies/postprocessing, (4) astrometric precision/target acquisition, and (5) polarimetry. We make suggestions on a path forward for each of these items.

  20. The new 800mm reflecting telescope

    Teske, Hans-Joachim

    The design and capabilities of the 800-mm Ritchey-Chretien system are described. The optical system of the telescope has an aperture ratio of 1:8; is suitable for photography in a 1.5 deg field with photoplates of 16 x 16 cm; and consists of primary and secondary hyperbolically deformed mirrors. The attachment of the mirrors, position rotator, and offset guider to the tube, which is a truss structure, is examined. The mount for the telescope is an equatorial fork type. The electronic control system is a 16-bit microcomputer system; the functions of the control system are discussed. The 8-m polyester dome of the telescope consists of a supporting steel structure carrying shell elements of glass fiber-reinforced polyester resins. Consideration is given to the auxiliary devices of the telescope.

  1. Beam Combination for Sparse Aperture Telescopes Project

    National Aeronautics and Space Administration — This proposal is for funding to continue development of an alternative beam combiner for Stellar Imager (SI), a 30-aperture, interferometric telescope chosen as one...

  2. Beam Combination for Sparse Aperture Telescopes Project

    National Aeronautics and Space Administration — The Stellar Imager, an ultraviolet, sparse-aperture telescope, was one of the fifteen Vision Missions chosen for a study completed last year. Stellar Imager will...

  3. Olkiluoto site description 2011

    NONE

    2012-12-15

    This fourth version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2008 with the data and knowledge obtained up to December 2010. A descriptive model of the site (the Site Descriptive Model, SDM), i.e. a model describing the geological and hydrogeological structure of the site, properties of the bedrock and the groundwater and its flow, and the associated interacting processes and mechanisms. The SDM is divided into six parts: surface system, geology, rock mechanics, hydrogeology, hydrogeochemistry and transport properties.

  4. Polemic and Descriptive Negations

    Horslund, Camilla Søballe

    2011-01-01

    semantics and pragmatics, negations can be used in three different ways, which gives rise to a typology of three different types of negations: 1) the descriptive negation, 2) the polemic negation, and 3) the meta-linguistic negation (Nølke 1999, 4). This typology illuminates the fact that the negation as...... meaning of the utterance (as in polemic negations), the negation will be articulated prominently in order to emphasise this importance. Likewise, if the negation is not central to the meaning of the utterance, it should not be articulated prominently. Moreover, it is plausible to expect descriptive...

  5. CRAC2 model description

    The CRAC2 computer code is a revised version of CRAC (Calculation of Reactor Accident Consequences) which was developed for the Reactor Safety Study. This document provides an overview of the CRAC2 code and a description of each of the models used. Significant improvements incorporated into CRAC2 include an improved weather sequence sampling technique, a new evacuation model, and new output capabilities. In addition, refinements have been made to the atmospheric transport and deposition model. Details of the modeling differences between CRAC2 and CRAC are emphasized in the model descriptions

  6. Olkiluoto site description 2011

    This fourth version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2008 with the data and knowledge obtained up to December 2010. A descriptive model of the site (the Site Descriptive Model, SDM), i.e. a model describing the geological and hydrogeological structure of the site, properties of the bedrock and the groundwater and its flow, and the associated interacting processes and mechanisms. The SDM is divided into six parts: surface system, geology, rock mechanics, hydrogeology, hydrogeochemistry and transport properties

  7. Planck intermediate results. XXVI. Optical identification and redshifts of Planck clusters with the RTT150 telescope

    Ade, P A R; Arnaud, M; Ashdown, M; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Barrena, R; Bartolo, N; Battaner, E; Benabed, K; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bikmaev, I; Böhringer, H; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Burenin, R; Burigana, C; Butler, R C; Calabrese, E; Carvalho, P; Catalano, A; Chamballu, A; Chiang, H C; Chon, G; Christensen, P R; Churazov, E; Clements, D L; Colombo, L P L; Comis, B; Couchot, F; Curto, A; Cuttaia, F; Dahle, H; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Diego, J M; Dole, H; Doré, O; Douspis, M; Ducout, A; Dupac, X; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Finelli, F; Flores-Cacho, I; Forni, O; Frailis, M; Franceschi, E; Frejsel, A; Fromenteau, S; Galeotta, S; Ganga, K; Génova-Santos, R T; Giard, M; Gilfanov, M; Giraud-Héraud, Y; Gjerløw, E; González-Nuevo, J; Górski, K M; Gruppuso, A; Hansen, F K; Hanson, D; Harrison, D L; Hempel, A; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Holmes, W A; Hornstrup, A; Hovest, W; Huffenberger, K M; Hurier, G; Jaffe, T R; Jones, W C; Juvela, M; Keihanen, E; Keskitalo, R; Khamitov, I; Kisner, T S; Kneissl, R; Knoche, J; Kunz, M; Kurki-Suonio, H; Lagache, G; Lasenby, A; Lattanzi, M; Lawrence, C R; Leonardi, R; Levrier, F; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Mac\\'\\ias-Pérez, J F; Maino, D; Mandolesi, N; Maris, M; Martin, P G; Mart\\'\\inez-González, E; Masi, S; Matarrese, S; Mazzotta, P; Melin, J -B; Mendes, L; Mennella, A; Migliaccio, M; Miville-Deschenes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Nørgaard-Nielsen, H U; Novikov, D; Novikov, I; Oxborrow, C A; Pagano, L; Pajot, F; Paoletti, D; Pasian, F; Perdereau, O; Perotto, L; Perrotta, F; Pettorino, V; Piacentini, F; Piat, M; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Popa, L; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Reinecke, M; Remazeilles, M; Renault, C; Ricciardi, S; Ristorcelli, I; Rocha, G; Roman, M; Rosset, C; Rossetti, M; Roudier, G; Rubiño-Mart\\'\\in, J A; Rusholme, B; Sandri, M; Scott, D; Spencer, L D; Stolyarov, V; Sudiwala, R; Sunyaev, R; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Terenzi, L; Toffolatti, L; Tomasi, M; Tristram, M; Tucci, M; Valenziano, L; Valiviita, J; Van Tent, B; Vibert, L; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Wehus, I K; Yvon, D; Zacchei, A; Zonca, A

    2014-01-01

    We present the results of approximately three years of observations of Planck Sunyaev-Zeldovich (SZ) sources with the Russian-Turkish 1.5-m telescope (RTT150), as a part of the optical follow-up programme undertaken by the Planck collaboration. During this time period approximately 20% of all dark and grey clear time available at the telescope was devoted to observations of Planck objects. Some observations of distant clusters were also done at the 6-m Bolshoy Telescope Azimutal'ny (BTA) of the Special Astrophysical Observatory of the Russian Academy of Sciences. In total, deep, direct images of more than one hundred fields were obtained in multiple filters. We identified 47 previously unknown galaxy clusters, 41 of which are included in the Planck catalogue of SZ sources. The redshifts of 65 Planck clusters were measured spectroscopically and 14 more were measured photometrically. We discuss the details of cluster optical identifications and redshift measurements. We also present new spectroscopic redhifts f...

  8. SuperHERO: The Next Generation Hard X-Ray HEROES Telescope

    Wilson-Hodge, Colleen A.; Gaskin, Jessica A.; Christe, Steven D.; Elsner, Ronald F.; Ramsey, Brian D.; Seller, Paul; Shih, Albert Y.; Stuchlik, David W.; Swartz, Douglas A.; Tenant, Allyn F.; Wilson, Matthew D.

    2014-01-01

    SuperHERO is a new high-sensitivity Long Duration Balloon (LDB)-capable, hard-x-ray (20-75 keV) telescope for making novel astrophysics and heliophysics observations. The proposed SuperHERO payload will be developed jointly by the Astrophysics Office at NASA Marshall Space Flight Center, the Solar Physics Laboratory and Wallops Flight Facility at NASA Goddard Space Flight Center. SuperHERO is a follow-on payload to the High Energy Replicated Optics to Explore the Sun (HEROES) balloon-borne telescope that recently launched from Fort Sumner, NM in September of 2013. The HEROES core instrument is a hard x-ray telescope consisting of x-ray 109 optics configured into 8 modules. Each module is aligned to a matching gas-filled detector at a focal length of 6 m. SuperHERO will make significant improvements to the HEROES payload, including: new solid-state multi-pixel CdTe detectors, additional optics, the Wallops Arc-Second Pointer, alignment monitoring systems and lighter gondola.

  9. The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

    Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Henderson, S. W.; Hilton, G. C.; Hubmayr, J.; Koopman, B. J.; Lanen, J. V.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Ward, J. T.; Wollack, E. J.; Vavagiakis, E. M.

    2016-03-01

    The Atacama Cosmology Telescope Polarimeter (ACTPol) is a polarization sensitive receiver for the 6-m Atacama Cosmology Telescope (ACT) and measures the small angular scale polarization anisotropies in the cosmic microwave background (CMB). The full focal plane is composed of three detector arrays, containing over 3000 transition edge sensors (TES detectors) in total. The first two detector arrays, observing at 146 GHz, were deployed in 2013 and 2014, respectively. The third and final array is composed of multichroic pixels sensitive to both 90 and 146 GHz and saw first light in February 2015. Fabricated at NIST, this dichroic array consists of 255 pixels, with a total of 1020 polarization sensitive bolometers and is coupled to the telescope with a monolithic array of broad-band silicon feedhorns. The detectors are read out using time-division SQUID multiplexing and cooled by a dilution refrigerator at 110 mK. We present an overview of the assembly and characterization of this multichroic array in the lab, and the initial detector performance in Chile. The detector array has a TES detector electrical yield of 85 %, a total array sensitivity of less than 10 \\upmu K√{s} , and detector time constants and saturation powers suitable for ACT CMB observations.

  10. TALON - The Telescope Alert Operation Network System: Intelligent Linking of Distributed Autonomous Robotic Telescopes

    White, R R; Davis, H; Galassi, M; Starr, D; Vestrand, W T; Wozniak, P

    2004-01-01

    The internet has brought about great change in the astronomical community, but this interconnectivity is just starting to be exploited for use in instrumentation. Utilizing the internet for communicating between distributed astronomical systems is still in its infancy, but it already shows great potential. Here we present an example of a distributed network of telescopes that performs more efficiently in synchronous operation than as individual instruments. RAPid Telescopes for Optical Response (RAPTOR) is a system of telescopes at LANL that has intelligent intercommunication, combined with wide-field optics, temporal monitoring software, and deep-field follow-up capability all working in closed-loop real-time operation. The Telescope ALert Operations Network (TALON) is a network server that allows intercommunication of alert triggers from external and internal resources and controls the distribution of these to each of the telescopes on the network. TALON is designed to grow, allowing any number of telescope...

  11. Solar Rejection Filter for Large Telescopes

    Hemmati, Hamid; Lesh, James

    2009-01-01

    To reject solar radiation photons at the front aperture for large telescopes, a mosaic of large transmission mode filters is placed in front of the telescope or at the aperture of the dome. Filtering options for effective rejection of sunlight include a smaller filter down-path near the focus of the telescope, and a large-diameter filter located in the front of the main aperture. Two types of large filters are viable: reflectance mode and transmittance mode. In the case of reflectance mode, a dielectric coating on a suitable substrate (e.g. a low-thermal-expansion glass) is arranged to reflect only a single, narrow wavelength and to efficiently transmit all other wavelengths. These coatings are commonly referred to as notch filter. In this case, the large mirror located in front of the telescope aperture reflects the received (signal and background) light into the telescope. In the case of transmittance mode, a dielectric coating on a suitable substrate (glass, sapphire, clear plastic, membrane, and the like) is arranged to transmit only a single wavelength and to reject all other wavelengths (visible and near IR) of light. The substrate of the large filter will determine its mass. At first glance, a large optical filter with a diameter of up to 10 m, located in front of the main aperture, would require a significant thickness to avoid sagging. However, a segmented filter supported by a structurally rugged grid can support smaller filters. The obscuration introduced by the grid is minimal because the total area can be made insignificant. This configuration can be detrimental to a diffraction- limited telescope due to diffraction effects at the edges of each sub-panel. However, no discernable degradation would result for a 20 diffraction-limit telescope (a photon bucket). Even the small amount of sagging in each subpanel should have minimal effect in the performance of a non-diffraction limited telescope because the part has no appreciable optical power. If the

  12. A high resolution silicon beam telescope

    We describe the design and present the performances of a charged particle telescope used for high resolution silicon pixel developments. A telescope made of four x and four y single-sided silicon microstrip layers was built, providing an r.m.s. position resolution of 1 μm for high energy charged particles. A signal over noise ratio of 130 was achieved with minimum ionizing particles

  13. Neutrino Telescopes' Sensitivity to Dark Matter

    Albuquerque, Ivone F. M.; Lamoureux, Jodi; Smoot, George F.

    2002-01-01

    The nature of the dark matter of the Universe is yet unknown and most likely is connected with new physics. The search for its composition is under way through direct and indirect detection. Fundamental physical aspects such as energy threshold, geometry and location are taken into account to investigate proposed neutrino telescopes of km^3 volume sensitivities to dark matter. These sensitivities are just sufficient to test a few WIMP scenarios. Telescopes of km^3 volume, such as IceCube, can...

  14. Thirty Meter Telescope Detailed Science Case: 2015

    Skidmore, Warren; Dell'Antonio, Ian; Fukugawa, Misato; Goswami, Aruna; Hao, Lei; Jewitt, David; Laughlin, Greg; Steidel, Charles; Hickson, Paul; Simard, Luc; Schöck, Matthias; Treu, Tommaso; Cohen, Judith; Anupama, G. C; Dickinson, Mark

    2015-01-01

    The TMT Detailed Science Case describes the transformational science that the Thirty Meter Telescope will enable. Planned to begin science operations in 2024, TMT will open up opportunities for revolutionary discoveries in essentially every field of astronomy, astrophysics and cosmology, seeing much fainter objects much more clearly than existing telescopes. Per this capability, TMT's science agenda fills all of space and time, from nearby comets and asteroids, to exoplanets, to the most dist...

  15. Practical considerations for pointing a binocular telescope

    De La Peña, Michele D.; Terrett, David L.; Thompson, David; Biddick, Christopher J.

    2010-07-01

    The Large Binocular Telescope (LBT) consists of two 8.4-meter primary mirrors on a common mount. When the telescope is complete, to complement the two primaries there will be two 0.9-meter adaptive secondaries and two tertiary mirror flats that all work to support a variety of Gregorian focal stations, as well as prime focus. A fundamental goal of the telescope is to perform interferometric observations, and therefore, there is a critical need for the ability to co-point the individual telescopes to high precision. Further, a unique aspect of the LBT is the comparatively large range over which the optics can be adjusted which provides flexibility for the acquisition of targets. In the most general case, an observer could be performing an observation using different targets, within constraints, with different instruments on each of the two telescope sides, with different observing duty cycles. As a consequence of the binocular nature of the telescope and the number of possible observing combinations, there are unique requirements imposed on the Telescope Control System (TCS), and in particular, on the Pointing Control Subsystem (PCS). It is the responsibility of the PCS to arbitrate the pointing requests made on the two sides of the telescope by the observers, incorporate guide updates, and generate tracking trajectories for the mount and the rotators, in conjunction with providing tip/tilt demands on the subsystem controlling the optical elements, and ensure each target remains on the specified location (i.e., pointing origin) in the focal plane during an active observation. This paper describes the current design and implementation of the LBT PCS.

  16. Novel optics for X-ray telescopes

    Hudec, René; Pína, L.; Semencová, V.; Inneman, A.; Skulinová, Michaela; Nekola, Martin

    Berlin : Springer, 2009 - (Brandl, B.), s. 1-8 ISBN 978-90-481-2232-5. [400 Years of Astronomical Telescopes. Leiden (NL), 29.09.2008-02.10.2008] R&D Projects: GA AV ČR IAAX01220701; GA ČR GP202/07/P510 Institutional research plan: CEZ:AV0Z10030501 Keywords : X-ray telescopes * X-ray optics * X-ray astronomy Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  17. Zone generator for Large Space Telescope technology

    Erickson, K. E.

    1974-01-01

    A concept is presented for monitoring the optical adjustment and performance of a Large Space Telescope which consists of a 1.2m diameter turntable with a laser stylus to operate at speeds up to 30 rpm. The focus of the laser stylus is under closed loop control. A technique for scribing zones of suitable depth, width, and uniformity applicable to large telescope mirrors is also reported.

  18. Giant Magellan Telescope Site Testing Summary

    Thomas-Osip, Joanna E.; McCarthy, Patrick; Prieto, Gabriel; Phillips, Mark M.; Johns, Matt

    2011-01-01

    Cerro Las Campanas located at Las Campanas Observatory (LCO) in Chile has been selected as the site for the Giant Magellan Telescope. We report results obtained since the commencement, in 2005, of a systematic site testing survey of potential GMT sites at LCO. Meteorological (cloud cover, temperature, pressure, wind, and humidity) and DIMM seeing data have been obtained at three potential sites, and are compared with identical data taken at the site of the twin Magellan 6.5m telescopes. In ad...

  19. James Webb Space Telescope (JWST) Optical Telescope Element (OTE) Development Status

    Feinberg, Lee D.

    2004-01-01

    The James Webb Space Telescope (JWST) Optical Telescope Element (OTE) is a segmented, cryogenic telescope scheduled for launch in 2011. In September of 2002, NASA selected prime contractor Northrop Grumman Space Technology (NGST) to build the observatory including management of the OTE. NGST is teamed with subcontractors Ball Aerospace, Alliant Techsystems (ATK). and Kodak. The team has completed several significant design, technology, architecture definition, and manufacturing milestones in the past year that are summarized in this paper.

  20. Large Size Telescope camera support structures for the Cherenkov Telescope Array

    Deleglise, G.; Geffroy, N.; Lamanna, G.; Consortium, for The Cherenkov Telescope Array

    2013-01-01

    The design of the camera support structures for the Cherenkov Telescope Array (CTA) Large Size Telescopes (LSTs) is based on an elliptical arch geometry reinforced along its orthogonal projection by two symmetric sets of stabilizing ropes. The main requirements in terms of minimal camera displacement, minimal weight, minimal shadowing on the telescope mirror, maximal strength of the structures and fast dynamical stabilization have led to the application of Carbon Fibre Plastic Reinforced (CFP...

  1. New rock salt-related oxides Li{sub 3}M{sub 2}RuO{sub 6} (M=Co, Ni): Synthesis, structure, magnetism and electrochemistry

    Laha, S. [Departamento de Químicas Inorganica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India); Morán, E., E-mail: emoran@quim.ucm.es [Departamento de Químicas Inorganica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Sáez-Puche, R.; Alario-Franco, M.Á.; Dos santos-Garcia, A.J. [Departamento de Químicas Inorganica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Gonzalo, E.; Kuhn, A.; García-Alvarado, F. [Universidad CEU San Pablo, Facultad de Farmacia, Departamento de Química, 28668 Boadilla del Monte, Madrid (Spain); Sivakumar, T.; Tamilarasan, S.; Natarajan, S.; Gopalakrishnan, J. [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India)

    2013-07-15

    We describe the synthesis, crystal structure, magnetic and electrochemical characterization of new rock salt-related oxides of formula, Li{sub 3}M{sub 2}RuO{sub 6} (M=Co, Ni). The M=Co oxide adopts the LiCoO{sub 2} (R-3m) structure, where sheets of LiO{sub 6} and (Co{sub 2}/Ru)O{sub 6} octahedra are alternately stacked along the c-direction. The M=Ni oxide also adopts a similar layered structure related to Li{sub 2}TiO{sub 3}, where partial mixing of Li and Ni/Ru atoms lowers the symmetry to monoclinic (C2/c). Magnetic susceptibility measurements reveal that in Li{sub 3}Co{sub 2}RuO{sub 6}, the oxidation states of transition metal ions are Co{sup 3+} (S=0), Co{sup 2+} (S=1/2) and Ru{sup 4+} (S=1), all of them in low-spin configuration and at 10 K, the material orders antiferromagnetically. Analogous Li{sub 3}Ni{sub 2}RuO{sub 6} presents a ferrimagnetic behavior with a Curie temperature of 100 K. The differences in the magnetic behavior have been explained in terms of differences in the crystal structure. Electrochemical studies correlate well with both magnetic properties and crystal structure. Li-transition metal intermixing may be at the origin of the more impeded oxidation of Li{sub 3}Ni{sub 2}RuO{sub 6} when compared to Li{sub 3}Co{sub 2}RuO{sub 6}. Interestingly high first charge capacities (between ca. 160 and 180 mAh g{sup −1}) corresponding to ca. 2/3 of theoretical capacity are reached albeit, in both cases, capacity retention and cyclability are not satisfactory enough to consider these materials as alternatives to LiCoO{sub 2}. - Graphical abstract: Two new rock salt related oxides of formula, Li{sub 3}M{sub 2}RuO{sub 6}, (M=Co, Ni) have been prepared. The M=Co oxide adopts the LiCoO{sub 2} (R-3m) structure and the M=Ni oxide adopts a similar layered structure related to Li{sub 2}TiO{sub 3,} monoclinic (C2/c), with partial mixing of Li and Ni/Ru atoms. For Li{sub 3}Co{sub 2}RuO{sub 6}, oxidation state for Ru is 4+ and antiferromagnetic (AFM) order is

  2. New rock salt-related oxides Li3M2RuO6 (M=Co, Ni): Synthesis, structure, magnetism and electrochemistry

    We describe the synthesis, crystal structure, magnetic and electrochemical characterization of new rock salt-related oxides of formula, Li3M2RuO6 (M=Co, Ni). The M=Co oxide adopts the LiCoO2 (R-3m) structure, where sheets of LiO6 and (Co2/Ru)O6 octahedra are alternately stacked along the c-direction. The M=Ni oxide also adopts a similar layered structure related to Li2TiO3, where partial mixing of Li and Ni/Ru atoms lowers the symmetry to monoclinic (C2/c). Magnetic susceptibility measurements reveal that in Li3Co2RuO6, the oxidation states of transition metal ions are Co3+ (S=0), Co2+ (S=1/2) and Ru4+ (S=1), all of them in low-spin configuration and at 10 K, the material orders antiferromagnetically. Analogous Li3Ni2RuO6 presents a ferrimagnetic behavior with a Curie temperature of 100 K. The differences in the magnetic behavior have been explained in terms of differences in the crystal structure. Electrochemical studies correlate well with both magnetic properties and crystal structure. Li-transition metal intermixing may be at the origin of the more impeded oxidation of Li3Ni2RuO6 when compared to Li3Co2RuO6. Interestingly high first charge capacities (between ca. 160 and 180 mAh g−1) corresponding to ca. 2/3 of theoretical capacity are reached albeit, in both cases, capacity retention and cyclability are not satisfactory enough to consider these materials as alternatives to LiCoO2. - Graphical abstract: Two new rock salt related oxides of formula, Li3M2RuO6, (M=Co, Ni) have been prepared. The M=Co oxide adopts the LiCoO2 (R-3m) structure and the M=Ni oxide adopts a similar layered structure related to Li2TiO3, monoclinic (C2/c), with partial mixing of Li and Ni/Ru atoms. For Li3Co2RuO6, oxidation state for Ru is 4+ and antiferromagnetic (AFM) order is found below 10 K while for the analogous Li3Ni2RuO6 , Ru oxidation state is 5+ and a ferrimagnetic (FM) behavior with a Curie temperature of 100 K is found. Electrochemical studies correlate well with both

  3. Reliability-centered maintenance for ground-based large optical telescopes and radio antenna arrays

    Marchiori, G.; Formentin, F.; Rampini, F.

    2014-07-01

    In the last years, EIE GROUP has been more and more involved in large optical telescopes and radio antennas array projects. In this frame, the paper describes a fundamental aspect of the Logistic Support Analysis (LSA) process, that is the application of the Reliability-Centered Maintenance (RCM) methodology for the generation of maintenance plans for ground-based large optical telescopes and radio antennas arrays. This helps maintenance engineers to make sure that the telescopes continue to work properly, doing what their users require them to do in their present operating conditions. The main objective of the RCM process is to establish the complete maintenance regime, with the safe minimum required maintenance, carried out without any risk to personnel, telescope and subsystems. At the same time, a correct application of the RCM allows to increase the cost effectiveness, telescope uptime and items availability, and to provide greater understanding of the level of risk that the organization is managing. At the same time, engineers shall make a great effort since the initial phase of the project to obtain a telescope requiring easy maintenance activities and simple replacement of the major assemblies, taking special care on the accesses design and items location, implementation and design of special lifting equipment and handling devices for the heavy items. This maintenance engineering framework is based on seven points, which lead to the main steps of the RCM program. The initial steps of the RCM process consist of: system selection and data collection (MTBF, MTTR, etc.), definition of system boundaries and operating context, telescope description with the use of functional block diagrams, and the running of a FMECA to address the dominant causes of equipment failure and to lay down the Critical Items List. In the second part of the process the RCM logic is applied, which helps to determine the appropriate maintenance tasks for each identified failure mode. Once

  4. Evaluation of Ca3(Co,M2O6 (M=Co, Fe, Mn, Ni as new cathode materials for solid-oxide fuel cells

    Fushao Li

    2015-10-01

    Full Text Available Series compounds Ca3(Co0.9M0.12O6 (M=Co, Fe, Mn, Ni with hexagonal crystal structure were prepared by sol–gel route as the cathode materials for solid oxide fuel cells (SOFCs. Effects of the varied atomic compositions on the structure, electrical conductivity, thermal expansion and electrochemical performance were systematically evaluated. Experimental results showed that the lattice parameters of Ca3(Co0.9Fe0.12O6 and Ca3(Co0.9Mn0.12O6 were both expanded to certain degree. Electron-doping and hole-doping effects were expected in Ca3(Co0.9Mn0.12O6 and Ca3(Co0.9Ni0.12O6 respectively according to the chemical states of constituent elements and thermal-activated behavior of electrical conductivity. Thermal expansion coefficients (TEC of Ca3(Co0.9M0.12O6 were measured to be distributed around 16×10−6 K−1, and compositional elements of Fe, Mn, and Ni were especially beneficial for alleviation of the thermal expansion problem of cathode materials. By using Ca3(Co0.9M0.12O6 as the cathodes operated at 800 °C, the interfacial area-specific resistance varied in the order of M=Co6 (M=Co, Fe, Mn, Ni can be used as the cost-effective cathode materials for SOFCs.

  5. Transfection with the ribozyme targeting HPVE6 mRNA results in growth inhibition of E6-expressing cervical carcinoma cells

    郑燕芳; 张积仁

    2003-01-01

    Objective: To acquire a ribozyme against the E6 gene of human papillomaviruses type 16 (HPV16E6) and investigate its effects on the phenotypes and gene expression of cervical cancer cell line. Methods: Anti-HPV16E6 ribozyme (HRz) was designed by computer programs and its activity identified by cleavage experiment in vitro before its transfection via lipofectin into CaSKi cells with the empty eucaryotic expression plasmid transfection of the cells also performed, the resultant cells designated as CaSKi-R, CaSKi-P respectively. The morphology and the soft agar forming ability were studied in CaSKi cells and the transfected cells, and the expression of E6, proliferating cell nuclear antigen (PCNA) and C-erbB-2 genes assayed by flow cytometry. The tumorgenicity of each cell line was evaluated in nude mice receiving inoculations of CaSKi, CaSKi-R and CaSKi-P cells separately, while in one group, both CaSKi and CaSKi-R cells were inoculated on different sides of the mice. Results: HRz was able to cleave HPV16E6 mRNA in a site-specific manner and could be expressed stably in transfected CaSKi cells. Northern blot analysis showed that E6 mRNA was less in CaSKi-R than in CaSKi cells, and no significant difference in the morphology and growth rate was observed between CaSKi and CaSKi-P cells, but the growth rate CaSKi-R was lowered. The colony-forming rate of CaSKi-P in soft agar was similar to that of CaSKi cells, while that of CaSKi-R was decreased. Flow cytometry showed that anti-HPV16E6 ribozyme reduced the expression of E6, PCNA and C-erbB-2 genes in CaSKi-R cells, but not in CaSKi-P cells. The tumorgenicity of CaSKi-R in nude mice was decreased compared with CaSKi cells. Conclusion: HRz can partially reverse the malignant phenotype of CaSKi cells, possibly due to decreased E6 gene expression, and the consequent decrease of PCNA and C-erbB-2 gene expressions.

  6. The Description of Polarization

    Mweene, Habatwa V.

    2005-01-01

    In this paper, we extend to polarization the method we have recently employed to treat spin. We are led to a generalization of its treatment. Thus, we are able to connect its matrix treatment to first principles, and we obtain the most generalized probability amplitudes and operators for its description.

  7. Erasure Multiple Descriptions

    Ahmed, Ebad

    2010-01-01

    We consider a binary erasure version of the n-channel multiple descriptions problem with symmetric descriptions, i.e., the rates of the n descriptions are the same and the distortion constraint depends only on the number of messages received. We consider the case where there is no excess rate for every k out of n descriptions. Our goal is to characterize the achievable distortions D_1, D_2,...,D_n. We measure the fidelity of reconstruction using two distortion criteria: an average-case distortion criterion, under which distortion is measured by taking the average of the per-letter distortion over all source sequences, and a worst-case distortion criterion, under which distortion is measured by taking the maximum of the per-letter distortion over all source sequences. We present achievability schemes, based on random binning for average-case distortion and systematic MDS (maximum distance separable) codes for worst-case distortion, and prove optimality results for the corresponding achievable distortion region...

  8. Tore Supra: technical description

    This report is aimed, after a brief recall of physics and technologic perspectives of Tore Supra, at giving a detailed description of the basic machine; details of each component are defined. Volume 1 is specifically concerned with the general aspects of Tore Supra and the toroidal field system

  9. Generalizing: The descriptive struggle

    Barney G. Glaser, Ph.D.; Hon Ph.D.

    2006-11-01

    Full Text Available The literature is not kind to the use of descriptive generalizations. Authors struggle and struggle to find and rationalize a way to use them and then fail in spite of trying a myriad of work-arounds. And then we have Lincoln and Guba’s famous statement: “The only generalization is: there is no generalization” in referring to qualitative research. (op cit, p. 110 They are referring to routine QDA yielding extensive descriptions, but which tacitly include conceptual generalizations without any real thought of knowledge about them. In this chapter I wish to explore this struggle for the purpose of explaining that the various contra arguments to using descriptive generalizations DO NOT apply to the ease of using conceptual generalizations yielded in SGT and especially FGT. I will not argue for the use of descriptive generalization. I agree with Lincoln and Guba with respect to QDA, “the only generalization is: there is no generalization.” It is up to the QDA methodologists, of whom there are many; to continue the struggle and I wish them well.

  10. Descriptions of Earthworms

    Horst, R.

    1887-01-01

    During his last journey in Liberia, my colleague Mr. Büttiköfer had the opportunity to collect a number of earthworms under a mouldering palm-tree. Among them I met with some specimens of Ac. Büttikoferi, a species which I briefly described in this Journal, Vol. VI, p. 105. However this description

  11. Descriptive sensory evaluations

    Dehlholm, Christian

    . The new methods were compared to the Flash Profile, Napping and conventional descriptive profiling. Furthermore, an approach for applying confidence ellipses to Multiple Factor Analysis (MFA) results from the statistical package R were suggested for the graphical validation and comparisons. PN allowed...

  12. A Description Logic Primer

    Krötzsch, Markus; Horrocks, Ian

    2012-01-01

    This paper provides a self-contained first introduction to description logics (DLs). The main concepts and features are explained with examples before syntax and semantics of the DL SROIQ are defined in detail. Additional sections review light-weight DL languages, discuss the relationship to the Web Ontology Language OWL and give pointers to further reading.

  13. Synthesis, characterization of double perovskite Ca2MSbO6 (M = Dy, Fe, Cr, Al) materials via sol–gel auto-combustion and their catalytic properties

    Double perovskite-type oxide Ca2MSbO6 materials, where M = Dy, Fe, Cr, and Al, were prepared by using the sol–gel auto-combustion method. The role of different B-site cations on their synthesis, structures, morphologies and catalytic properties was investigated. The progress of double-perovskite type structure formation and the disappearance of the organic phases were monitored by infrared absorption spectroscopy (FTIR). Double perovskite oxide structures were evaluated using X-ray diffraction (XRD), while the microstructure of obtained compounds was studied using scanning electron microscopy (SEM). Also, BET surface areas were measured at the liquid nitrogen temperature by nitrogen adsorption. Catalytic properties of the obtained compounds were evaluated by test reaction of hydrogen peroxide decomposition. - Highlights: • Ca2MSbO6 double perovskites were obtained by sol–gel auto-combustion method. • Ca2MSbO6 (M = Dy, Fe, Cr and Al) as catalysts in H2O2 decomposition • Strong relationship between particles' shape, BET area and catalytic performance • Ca2FeSbO6 spherical grains show superior catalytic activity

  14. Linhuan Coke oven Cleaner Production 6m Comprehensiv%临涣焦化6m焦炉清洁生产的综合治理

    李峰

    2011-01-01

    The company adopts the new type JN60 6 m coke oven,the production task more nervous,smoke control in the production of absence of difficulty is large.According to the coke oven cleaner production requirements,the company put forward for clean,coking coal "smoke-free,purification tasteless",establishing comprehensive environmental protection to the new concept.First through the search the problems that exist,according to establish management plan,problems with close the technical innovation,to adjust,and the comprehensive management measures,coke oven management to a large volume of coke oven secondary standard.%我公司采用新型JN60型6 m焦炉,生产任务比较紧张,生产中的烟尘逸散控制难度较大。根据焦炉清洁生产要求,公司提出了"备煤无尘、炼焦无烟、净化无味",创建全方位环保新概念。首先通过查找存在的问题,根据问题确立治理方案,装满拉平、技改创新、以调代修等措施综合治理,焦炉管理达到大容积焦炉二级标准。

  15. Critical heat flux and post-critical heat flux performance of a 6-m, 37-element fully segmented bundle cooled by Freon-12

    A 6-m, 37-element, electrically heated bundle with full end plate simulation, cooled by Freon-12, has been tested for CHF (critical heat flux) and post-CHF conditions in the MR-3 Freon loop. The bundle was tested in a horizontal attitude and had a uniform axial heat flux distribution and radial heat flux depression. A total of 110 CHF points have been collected over the following range of water equivalent conditions: exit pressure 8.27 - 11.03 MPa, mass flux 1.38 - 8.14 Mg.m-2.s-1, inlet subcooling 0 - 500 kJ.kg-1, outlet quality 10% - 37%. The data have been correlated on both a systems and local conditions basis over a limited mass flux range to within 2.8% rms. Significant CHF increases over smooth bundle results have been observed along with significant CHF improvement over a two end plate bundle simulation in the lower mass flux ranges. A satisfactory axial drypatch spreading correlation has been determined and extensive drypatch wall superheat mapping has been performed

  16. Structural and magnetic properties of Prussian blue analogue molecular magnet Fe1.5[Cr(CN)6].mH2O

    Bhatt, Pramod; Meena, S. S.; Mukadam, M. D.; Yusuf, S. M.

    2016-05-01

    Molecular magnets, based on Prussian blue analogues, Fe1.5[Cr(CN)6].mH2O have been synthesized in the bulk as well as nanoparticle forms using a co-precipitation method, and their structural and magnetic properties have been investigated using x-ray diffraction (XRD) Mössbauer spectroscopy and dc magnetization. The XRD study confirms the single phase crystalline and nanoparticle nature of the compounds with a face centered cubic (fcc) structure of space group Fm3m. The values of lattice constant are found to be ~10.18(5) Å and ~9.98(9)Å, for the bulk and nanoparticle samples, respectively. The dc magnetization shows a Curie temperature (TC) of ~17 K and ~5 K for the bulk and nanopartcile samples, respectively. The Mossouber spectroscopy reveal that the compound shows spin flipping from the high spin (HS) Fe (CrIII-C≡N-FeII) to low spin (LS) FeII ions (CrIII-N≡C-FeII). Moreover, the TC and the HS state of the Fe ions decreases (converts to its LS states) with time as well as in the nanoparticle form compared to bulk.

  17. Monte Carlo studies of medium-size telescope designs for the Cherenkov Telescope Array

    Wood, M.; Jogler, T.; Dumm, J.; Funk, S.

    2016-01-01

    We present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parameters including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters representative of the proposed Davies-Cotton (DC) and Schwarzchild-Couder (SC) MST designs, we compare the performance of the arrays by examining the gamma-ray angular resolution and differential point-source sensitivity. We further investigate the array performance under a wide range of conditions, determining the impact of the number of telescopes, telescope separation, night sky background, and geomagnetic field. We find a 30-40% improvement in the gamma-ray angular resolution at all energies when comparing arrays with an equal number of SC and DC telescopes, significantly enhancing point-source sensitivity in the MST energy range. We attribute the increase in point-source sensitivity to the improved optical point-spread function and smaller pixel size of the SC telescope design.

  18. Fiber Optics at ESO - Part Two - Fiber Optics Multiple Object Spectroscopy at the 3.6-METER Telescope

    Enard, D.; Lund, G.; Tarenghi, M.

    1983-09-01

    During a 6-day test period late in November 1982, a prototype optical fiber device (nicknamed "Fiber Optopus") was tested at the 3.6 m telescope Cassegrain focus. The principle of this device, described in more detail in the following paragraphs, is such that the light from up to 50 randomly separated points on the sky (within the Cassegrain focus field of view) can be simultaneously guided via separate flexible optical fibers to the entrance slit of the B&C spectrograph. By making use of a two-dimensional detector such as a CCO the individual spectra, corresponding to each sampled point on the field, can be recorded simultaneously. When fully operational, the Fiber Optopus should enable a very strong reduction in telescope time to be achieved in observing programmes involving low resolution spectral mapping of extended fields. This feature will be of great interest to astronomers wishing to observe clusters of faint objects requiring long integration periods.

  19. New Radio Telescope Makes First Scientific Observations

    2001-05-01

    The world's two largest radio telescopes have combined to make detailed radar images of the cloud-shrouded surface of Venus and of a tiny asteroid that passed near the Earth. The images mark the first scientific contributions from the National Science Foundation's (NSF) new Robert C. Byrd Green Bank Telescope in West Virginia, which worked with the NSF's recently-upgraded Arecibo telescope in Puerto Rico. The project used the radar transmitter on the Arecibo telescope and the huge collecting areas of both telescopes to receive the echoes. GBT-Arecibo Radar Image of Maxwell Montes on Venus "These images are the first of many scientific contributions to come from the Robert C. Byrd Green Bank Telescope, and a great way for it to begin its scientific career," said Paul Vanden Bout, director of the National Radio Astronomy Observatory (NRAO). "Our congratulations go to the scientists involved in this project as well as to the hard-working staffs at Green Bank and Arecibo who made this accomplishment possible," Vanden Bout added. To the eye, Venus hides behind a veil of brilliant white clouds, but these clouds can be penetrated by radar waves, revealing the planet's surface. The combination of the Green Bank Telescope (GBT), the world's largest fully-steerable radio telescope, and the Arecibo telescope, the world's most powerful radar, makes an unmatched tool for studying Venus and other solar-system bodies. "Having a really big telescope like the new Green Bank Telescope to receive the radar echoes from small asteroids that are really close to the Earth and from very distant objects like Titan, the large moon of Saturn, will be a real boon to radar studies of the solar system." said Cornell University professor Donald Campbell, leader of the research team. Ten years ago, the radar system on NASA's Magellan spacecraft probed though the clouds of Venus to reveal in amazing detail the surface of the Earth's twin planet. These new studies using the GBT and Arecibo, the

  20. Multidimensional nonlinear descriptive analysis

    Nishisato, Shizuhiko

    2006-01-01

    Quantification of categorical, or non-numerical, data is a problem that scientists face across a wide range of disciplines. Exploring data analysis in various areas of research, such as the social sciences and biology, Multidimensional Nonlinear Descriptive Analysis presents methods for analyzing categorical data that are not necessarily sampled randomly from a normal population and often involve nonlinear relations. This reference not only provides an overview of multidimensional nonlinear descriptive analysis (MUNDA) of discrete data, it also offers new results in a variety of fields. The first part of the book covers conceptual and technical preliminaries needed to understand the data analysis in subsequent chapters. The next two parts contain applications of MUNDA to diverse data types, with each chapter devoted to one type of categorical data, a brief historical comment, and basic skills peculiar to the data types. The final part examines several problems and then concludes with suggestions for futu...

  1. RETRIEVAL EQUIPMENT DESCRIPTIONS

    The objective and the scope of this document are to list and briefly describe the major mobile equipment necessary for waste package (WP) retrieval from the proposed subsurface nuclear waste repository at Yucca Mountain. Primary performance characteristics and some specialized design features of the equipment are explained and summarized in the individual subsections of this document. There are no quality assurance requirements or QA controls in this document. Retrieval under normal conditions is accomplished with the same fleet of equipment as is used for emplacement. Descriptions of equipment used for retrieval under normal conditions is found in Emplacement Equipment Descriptions, DI: BCAF00000-01717-5705-00002 (a document in progress). Equipment used for retrieval under abnormal conditions is addressed in this document and consists of the following: (1) Inclined Plane Hauler; (2) Bottom Lift Transporter; (3) Load Haul Dump (LHD) Loader; (4) Heavy Duty Forklift for Emplacement Drifts; (5) Covered Shuttle Car; (6) Multipurpose Vehicle; and (7) Scaler

  2. Robotic Astronomy with the Faulkes Telescopes and Las Cumbres Observatory Global Telescope

    Lewis, Fraser; Roche, Paul; Stroud, Vanessa; Russell, David M

    2009-01-01

    We present results from ongoing science projects conducted by members of the Faulkes Telescope (FT) team and Las Cumbres Observatory Global Telescope (LCOGT). Many of these projects incorporate observations carried out and analysed by FT users, comprising amateur astronomers and schools. We also discuss plans for the further development of the LCOGT network.

  3. Robotic Astronomy with the Faulkes Telescopes and Las Cumbres Observatory Global Telescope

    Vanessa Stroud; Russell, David M.; Paul Roche; Fraser Lewis; Rachel Street

    2010-01-01

    We present results from ongoing science projects conducted by members of the Faulkes Telescope (FT) team and Las Cumbres Observatory Global Telescope (LCOGT). Many of these projects incorporate observations carried out and analysed by FT users, comprising amateur astronomers and schools. We also discuss plans for the further development of the LCOGT network.

  4. Monte Carlo comparison of mid-size telescope designs for the Cherenkov Telescope Array

    Jogler, T; Dumm, J

    2012-01-01

    The Cherenkov Telescope Array (CTA) is a future very high energy gamma-ray observatory. CTA will be comprised of small-, medium- and large-size telescopes covering an energy range from tens of GeV to hundreds of TeV and will surpass existing telescopes in sensitivity by an order of magnitude. The aim of our study is to find the optimal design for the medium-size telescopes (MSTs), which will determine the sensitivity in the key energy range between a few hundred GeV to about ten TeV. To study the effect of the telescope design parameters on the array performance, we simulated arrays of 61 MSTs with 120 m spacing and a variety of telescope configurations. We investigated the influence of the primary telescope characteristics including optical resolution, pixel size, and light collection area on the total array performance with a particular emphasis on telescope configurations with imaging performance similar to the proposed Davis-Cotton (DC) and Schwarzschild-Couder (SC) MST designs. We compare the performance...

  5. Monte Carlo comparison of medium-size telescope designs for the Cherenkov Telescope Array

    Jogler, T; Dumm, J

    2013-01-01

    The Cherenkov Telescope Array (CTA) is a future very high energy gamma-ray observatory. CTA will be comprised of small-,medium- and large-size telescopes covering an energy range from tens of GeV to hundreds of TeV and will surpass existing telescopes in sensitivity by an order of magnitude. The aim of our study is to find the optimal design for the medium-size telescopes (MSTs), which will determine the sensitivity in the key energy range between a few hundred GeV to about ten TeV. To study the effect of the telescope design parameters on the array performance, we simulated arrays of 61 MSTs with 120 m spacing and a variety of telescope configurations. We investigated the influence of the primary telescope characteristics including optical resolution, pixel size, and light collection area on the total array performance with a particular emphasis on telescope configurations with imaging performance similar to the proposed Davies-Cotton (DC) and Schwarzschild-Couder (SC) MST designs. We compare the performance...

  6. From description to prescription

    McQuaid, Sara Dybris

    From Description to Prescription: Politics of Recognition, Consociational Theory and the Conflict in Northern Ireland. Within academic discourses on Northern Ireland the politics of recognition and particularly the theory of consociational democracy has made a profound impact. First introduced by...... theory to its current prominent position within the academy. Structuring these interpretations alongside evolving constitutional policy, the paper will argue that although consociationalism has developed as an indeterminate research design, the inherent logic of managing diversity on the basis of...

  7. Humanoid Motion Description Language

    Choi, Ben; Chen, Yanbing

    2002-01-01

    In this paper we propose a description language for specifying motions for humanoid robots and for allowing humanoid robots to acquire motor skills. Locomotion greatly increases our ability to interact with our environments, which in turn increases our mental abilities. This principle also applies to humanoid robots. However, there are great difficulties to specify humanoid motions and to represent motor skills, which in most cases require four-dimensional space representations. We propose a ...

  8. TMACS system description

    This document provides a description of the Tank Monitor and Control System (TMACS). It is intended as an introduction for those persons unfamiliar with the system as well as a reference document for the users, maintenance personnel, and system designers. In addition to describing the system, the document outlines the associated drawing documentation, provides maintenance and spare parts information, and discusses other TMACS documents that provide additional detail

  9. Olkiluoto site description 2006

    This second version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2004 (Posiva 2005) with the data and knowledge obtained up to December 2005. The main product of the modelling has been to develop a descriptive model of the site (the Site Descriptive Model), i.e. a model describing the geometry, properties of the bedrock and the water and the associated interacting processes and mechanisms. For practical reasons, the Site Descriptive Model is divided into five parts: surface system, geology, rock mechanics, hydrogeology and hydrogeochemistry, which are presented in individual chapters. Four separated models are presented: the geological, rock mechanics, hydrogeological and hydrogeochemical models. The consistency between the hydrogeological and hydrogeochemical models is assessed in a joint chapter. Chapter 1 presents an outline of the report, explains the background to its development and sets out its objectives and scope. It is also introduces and explains the integrated modelling methodology, the nomenclature used in the descriptions of the models and the prediction/outcome studies. Chapter 2 provides a brief overview of the data used for producing the Site Description. Chapters 3 to 8 present the descriptive modelling, which involves interpreting data, interpolating or extrapolating between measurement points and calibrating the model against data, based on the various assumptions made about each conceptual model. Chapter 9 presents the results of the prediction/outcome studies performed during 2005 and Chapter 10 the overall consistency and confidence assessment. Overall conclusions are provided in Chapter 11. The main advances since Site Report 2004 are: A new geological model is presented in Chapter 4, representing a significant change from Bedrock Model 2003/1. There has been extensive use of geological data, whereas hydrogeological data have deliberately not been used and more

  10. XML Diagnostics Description Standard

    A standard for the self-description of fusion plasma diagnostics will be presented, based on the Extensible Markup Language (XML). The motivation is to maintain and organise the information on all the components of a laboratory experiment, from the hardware to the access security, to save time and money when problems arises. Since there is no existing standard to organise this kind of information, every Association stores and organises each experiment in different ways. This can lead to severe problems when the organisation schema is poorly documented or written in national languages. The exchange of scientists, researchers and engineers between laboratories is a common practice nowadays. Sometimes they have to install new diagnostics or to update existing ones and frequently they lose a great deal of time trying to understand the currently installed system. The most common problems are: no documentation available; the person who understands it has left; documentation written in the national language. Standardisation is the key to solving all the problems mentioned. From the commercial information on the diagnostic (component supplier; component price) to the hardware description (component specifications; drawings) to the operation of the equipment (finite state machines) through change control (who changed what and when) and internationalisation (information at least in the native language and in English), a common XML schema will be proposed. This paper will also discuss an extension of these ideas to the self-description of ITER plant systems, since the problems will be identical. (author)

  11. Roughness tolerances for Cherenkov telescope mirrors

    Tayabaly, K.; Spiga, D.; Canestrari, R.; Bonnoli, G.; Lavagna, M.; Pareschi, G.

    2015-09-01

    The Cherenkov Telescope Array (CTA) is a forthcoming international ground-based observatory for very high-energy gamma rays. Its goal is to reach sensitivity five to ten times better than existing Cherenkov telescopes such as VERITAS, H.E.S.S. or MAGIC and extend the range of observation to energies down to few tens of GeV and beyond 100 TeV. To achieve this goal, an array of about 100 telescopes is required, meaning a total reflective surface of several thousands of square meters. Thence, the optimal technology used for CTA mirrors' manufacture should be both low-cost (~1000 euros/m2) and allow high optical performances over the 300-550 nm wavelength range. More exactly, a reflectivity higher than 85% and a PSF (Point Spread Function) diameter smaller than 1 mrad. Surface roughness can significantly contribute to PSF broadening and limit telescope performances. Fortunately, manufacturing techniques for mirrors are now available to keep the optical scattering well below the geometrically-predictable effect of figure errors. This paper determines first order surface finish tolerances based on a surface microroughness characterization campaign, using Phase Shift Interferometry. That allows us to compute the roughness contribution to Cherenkov telescope PSF. This study is performed for diverse mirror candidates (MAGIC-I and II, ASTRI, MST) varying in manufacture technologies, selected coating materials and taking into account the degradation over time due to environmental hazards.

  12. Schwarzschild-Couder telescope for the Cherenkov Telescope Array: Development of the Optical System

    Rousselle, Julien; Errando, Manel; Humensky, Brian; Mukherjee, Reshmi; Nieto, Daniel; Okumura, Akira; Vassiliev, Vladimir

    2013-01-01

    The CTA (Cherenkov Telescope Array) is the next generation ground-based experiment for very high-energy (VHE) gamma-ray observations. It will integrate several tens of imaging atmospheric Cherenkov telescopes (IACTs) with different apertures into a single astronomical instrument. The US part of the CTA collaboration has proposed and is developing a novel IACT design with a Schwarzschild-Couder (SC) aplanatic two mirror optical system. In comparison with the traditional single mirror Davies-Cotton IACT the SC telescope, by design, can accommodate a wide field-of-view, with significantly improved imaging resolution. In addition, the reduced plate scale of an SC telescope makes it compatible with highly integrated cameras assembled from silicon photo multipliers. In this submission we report on the status of the development of the SC optical system, which is part of the effort to construct a full-scale prototype telescope of this type at the Fred Lawrence Whipple Observatory in southern Arizona.

  13. Single-Mirror Small-Size Telescope structure for the Cherenkov Telescope Array

    Niemiec, Jacek; Dyrda, Michał; Kochański, Wojciech; Ludwin, Jaromir; Stodulski, Marek; Ziółkowski, Paweł

    2013-01-01

    A single-mirror small-size (1M-SST) Davies-Cotton telescope has been proposed for the southern observatory of the Cherenkov Telescope Array (CTA) by a consortium of scientific institutions from Poland, Switzerland, and Germany. The telescope has a 4 m diameter reflector and will be equipped with a fully digital camera based on Geiger avalanche photodiodes (APDs). Such a design is particularly interesting for CTA because it represents a very simple, reliable, and cheap solution for a SST. Here we present the design and the characteristics of the mechanical structure of the 1M-SST telescope and its drive system. We also discuss the results of a finite element method analysis in order to demonstrate the conformance of the design with the CTA specifications and scientific objectives. In addition, we report on the current status of the construction of a prototype telescope structure at the Institute of Nuclear Physics PAS in Krakow.

  14. Hydrogen storage properties of LaMgNi3.6M0.4 (M = Ni, Co, Mn, Cu, Al) alloys

    Highlights: • La–Mg–Ni system AB2-type alloys were prepared by induction melting. • Structures and lattice parameters were analysed by XRD. • Hydrogen absorption/desorption performances were studied. • Mechanisms of hydrogen absorption capacity fading were investigated. - Abstract: LaMgNi3.6M0.4 (M = Ni, Co, Mn, Cu, Al) alloys were prepared through induction melting process. The phase compositions and crystal structures were characterised via X-ray diffraction (XRD). The hydrogen storage properties, including activation performance, hydrogen absorption capacity, cycle stability, alloy particle pulverisation and plateau pressure, were systemically investigated. Results show that Ni, Co, Mn and Cu substitution alloys exhibit multiphase structures comprising the main phase LaMgNi4 and the secondary phase LaNi5. However, the secondary phase of the Al substitution alloy changes into LaAlNi4. The lattice parameters and cell volumes of the LaMgNi4 phase follow the order Ni < Co < Al < Cu < Mn. Activation is simplified through partial substitution of Ni with Al, Cu and Co. The hydrogen absorption capacities of all of the alloys are approximately 1.7 wt.% at the first activation process; however, they rapidly decrease with increasing cycle number. In addition, the stabilities of hydriding and dehydriding cycles decrease in the order Al > Co > Ni > Cu > Mn. Hydriding processes result in numerous cracks and amorphisation of the LaMgNi4 phase in the alloys. The p–c isotherms were determined by a Sieverts-type apparatus. Two plateaus were observed for the Ni, Co and Al substitution alloys, whereas only one plateau was found for Mn and Cu. This result was caused by the amorphisation of the LaMgNi4 phase during the hydriding cycles. Reversible absorption and desorption of hydrogen are difficult to achieve. Substitutions of Ni with Co, Mn, Cu and Al significantly influence the reduction of hysteresis between hydriding and dehydriding

  15. Model construction and superconductivity analysis of organic conductors β-(BDA-TTP)2MF6 (M = P, As, Sb and Ta) based on first-principles band calculation

    Aizawa, H.; Kuroki, K.; Yasuzuka, S.; Yamada, J.

    2012-11-01

    We perform a first-principles band calculation for a group of quasi-two-dimensional organic conductors β-(BDA-TTP)2MF6 (M = P, As, Sb and Ta). The ab-initio calculation shows that the density of states is correlated with the bandwidth of the singly occupied (highest) molecular orbital, while it is not necessarily correlated with the unit-cell volume. The direction of the major axis of the cross section of the Fermi surface lies in the Γ-B-direction, which differs from that obtained by the extended Hückel calculation. Then, we construct a tight-binding model which accurately reproduces the ab-initio band structure. The obtained transfer energies give a smaller dimerization than in the extended Hückel band. As to the difference in the anisotropy of the Fermi surface, the transfer energies along the inter-stacking direction are smaller than those obtained in the extended Hückel calculation. Assuming spin-fluctuation-mediated superconductivity, we apply random phase approximation to a two-band Hubbard model. This two-band Hubbard model is composed of the tight-binding model derived from the first-principles band structure and an on-site (intra-molecule) repulsive interaction taken as a variable parameter. The obtained superconducting gap changes sign four times along the Fermi surface like in a d-wave gap, and the nodal direction is different from that obtained in the extended Hückel model. Anion dependence of Tc is qualitatively consistent with the experimental observation.

  16. Flower-like nanostructure MNb2O6 (M = Mn, Zn) with high surface area: Hydrothermal synthesis and enhanced photocatalytic performance

    Graphical abstract: - Highlights: • MNb2O6 was prepared by a mild two-step hydrothermal method. • Their flower-like nanostructure morphology was studied by SEM and TEM. • High BET surface areas for MnNb2O6 (∼50 m2/g) and ZnNb2O6 (∼100 m2/g). • Band gap energies were estimated by UV–vis diffuse reflectance spectra. • Photocatalytic activities were evaluated under UV-light irradiation. - Abstract: Nano-scaled MNb2O6 (M = Mn, Zn) was successfully synthesized via a two-step hydrothermal method. It is important to control the exact pH of the reaction solution in order to obtain pure products. The as-prepared samples both crystallize in the columbite structure. Interestingly, the products possess a flower-like morphology in a pseudo-six-fold symmetry, which is in fact arrayed by two-dimensional nanosheets. Their surface areas (51 m2/g for MnNb2O6 and 103 m2/g for ZnNb2O6) are about 25–50 times of those prepared by solid state reaction. UV–vis diffuse reflectance spectra show the nano-scaled sample has a stronger absorption and a narrower band gap than its bulk form. The estimated band gap energies are 2.70 eV (MnNb2O6) and 3.77 eV (ZnNb2O6), respectively. The nano-scaled ZnNb2O6 exhibits a double enhancement of photocatalytic activity in the decolorization of methylene blue than bulk ZnNb2O6

  17. Recent Developments in the Alignment and Test Plans for the James Webb Space Telescope Integrated Science Instrument Module

    Ohl, Raymond

    2008-01-01

    The James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (approximately 40K). The JWST Observatory architecture includes the Optical Telescope Element (OTE) and the Integrated Science Instrument Module (ISIM) element that contains four science instruments (SI) including a Guider. The SIs and Guider are mounted to a composite metering structure with outer dimensions of 2.1 x 2.2 x 1.9m. The SI and Guider units are integrated to the ISIM structure and optically tested at NASA/Goddard Space Flight Center as an instrument suite using an OTE SIMulator (OSIM). OSIM is a high-fidelity, cryogenic JWST telescope simulator that features a approximately 1.5m diameter powered mirror. The SIs are aligned to the structure's coordinate system under ambient, clean room conditions using laser tracker and theodolite metrology. Temperature-induced mechanical SI alignment and structural changes are measured using a photogrammetric measurement system at ambient and cryogenic temperatures. OSIM is aligned to the ISIM mechanical coordinate system at the cryogenic operating temperature via internal mechanisms and feedback from alignment sensors in six degrees of freedom. SI performance, including focus, pupil shear and wavefront error, is evaluated at the operating temperature using OSIM. We present an updated plan for the assembly and ambient and cryogenic optical alignment, test and verification of the ISIM element.

  18. Accurate Telescope Mount Positioning with MEMS Accelerometers

    Mészáros, László; Pál, András; Csépány, Gergely

    2014-01-01

    This paper describes the advantages and challenges of applying microelectromechanical accelerometer systems (MEMS accelerometers) in order to attain precise, accurate and stateless positioning of telescope mounts. This provides a completely independent method from other forms of electronic, optical, mechanical or magnetic feedback or real-time astrometry. Our goal is to reach the sub-arcminute range which is well smaller than the field-of-view of conventional imaging telescope systems. Here we present how this sub-arcminute accuracy can be achieved with very cheap MEMS sensors and we also detail how our procedures can be extended in order to attain even finer measurements. In addition, our paper discusses how can a complete system design be implemented in order to be a part of a telescope control system.

  19. Neutrino telescopes' sensitivity to dark matter

    The nature of the dark matter of the Universe is yet unknown and most likely is connected with new physics. The search for its composition is underway through direct and indirect detection. Fundamental physical aspects such as energy threshold, geometry and location are taken into account to investigate proposed neutrino telescopes of km3 volume sensitivities to dark matter. These sensitivities are just sufficient to test a few weakly interacting massive particle scenarios. Telescopes of km3 volume, such as IceCube, can definitely discover or exclude superheavy (M>1010 GeV) strong interacting massive particles (simpzillas). Smaller neutrino telescopes such as ANTARES, AMANDA-II and NESTOR can probe a large region of simpzilla parameter space

  20. Mirror Development for the Cherenkov Telescope Array

    Förster, A; Baba, H; Bähr, J; Bonardi, A; Bonnoli, G; Brun, P; Canestrari, R; Chadwick, P; Chikawa, M; Carton, P -H; De Souza, V; Dipold, J; Doro, M; Durand, D; Dyrda, M; Giro, E; Glicenstein, J -F; Hanabata, Y; Hayashida, M; Hrabovski, M; Jeanney, C; Kagaya, M; Katagiri, H; Lessio, L; MANDAT, D; Mariotti, M; Medina, C; Michałowski, J; Micolon, P; Nakajima, D; Niemiec, J; Nozato, A; Palatka, M; Pareschi, G; Pech, M; Peyaud, B; Pühlhofer, G; Rataj, M; Rodeghiero, G; Rojas, G; Rousselle, J; Sakonaka, R; Schovanek, P; Seweryn, K; Schultz, C; Shu, S; Stinzing, F; Stodulski, M; Teshima, M; Travniczek, P; Van Eldik, C; Vassiliev, V; Wiśniewski, Ł; Wörnlein, A; Yoshida, T

    2013-01-01

    The Cherenkov Telescope Array (CTA) is a planned observatory for very-high energy gamma-ray astronomy. It will consist of several tens of telescopes of different sizes, with a total mirror area of up to 10,000 square meters. Most mirrors of current installations are either polished glass mirrors or diamond-turned aluminium mirrors, both labour intensive technologies. For CTA, several new technologies for a fast and cost-efficient production of light-weight and reliable mirror substrates have been developed and industrial pre-production has started for most of them. In addition, new or improved aluminium-based and dielectric surface coatings have been developed to increase the reflectance over the lifetime of the mirrors compared to those of current Cherenkov telescope instruments.

  1. Tracking subsystem of the SOFIA telescope

    Bittner, Hermann; Braeuninger, Christoph; Dierks, Andreas; Erdmann, Matthias; Erhard, Markus; Lattner, Klaus; Schmolke, Juergen

    2000-06-01

    The Tracking Subsystem of the SOFIA telescope consists of three high performance imagers and a dedicated tracking control unit. There are two boresighted imagers for target acquisition and tracking, one with a wide (6 degrees) and one with a fine (70 arcmin) field-of-view, and one main- telescope-optics sharing imager with a narrow field-of-view (8 arcmin) for high performance tracking. From the recorded stellar images, tracking error signals are generated by the tracker controller. The tracker controller has several features to support various tracking schemes such as tracking the telescope as an inertial platform, on- axis/offset tracking, and limb tracking. The tracker has three modes, i.e. positioning, tracking and `override'. Special features are the handling of so-called areas-of- interest in the inertial reference frame and the external imager synchronization. The paper presents the design and functional/operational performance of the imagers and the tracking control unit.

  2. Adaptive Real Time Imaging Synthesis Telescopes

    Wright, Melvyn

    2012-01-01

    The digital revolution is transforming astronomy from a data-starved to a data-submerged science. Instruments such as the Atacama Large Millimeter Array (ALMA), the Large Synoptic Survey Telescope (LSST), and the Square Kilometer Array (SKA) will measure their accumulated data in petabytes. The capacity to produce enormous volumes of data must be matched with the computing power to process that data and produce meaningful results. In addition to handling huge data rates, we need adaptive calibration and beamforming to handle atmospheric fluctuations and radio frequency interference, and to provide a user environment which makes the full power of large telescope arrays accessible to both expert and non-expert users. Delayed calibration and analysis limit the science which can be done. To make the best use of both telescope and human resources we must reduce the burden of data reduction. Our instrumentation comprises of a flexible correlator, beam former and imager with digital signal processing closely coupled...

  3. The Sooner: a Large Robotic Telescope

    Chincarini, G; Covino, S; Molinari, E; Benetti, S; Vitali, F; Bonoli, C; Bortoletto, F; Cascone, E; Cosentino, R; D'Alessio, F; D'Avanzo, P; De Caprio, V; Della Valle, M; Fernandez-Soto, A; Fugazza, D; Giro, E; Gomboc, A; Guidorzi, C; Magrin, D; Malaspina, G; Mankiewicz, L; Margutti, R; Mazzoleni, R; Nicastro, L; Riva, A; Riva, M; Salvaterra, R; Spano, P; Sperandio, M; Stefanon, M; Tosti, G; Testa, V

    2010-01-01

    The approach of Observational Astronomy is mainly aimed at the construction of larger aperture telescopes, more sensitive detectors and broader wavelength coverage. Certainly fruitful, this approach turns out to be not completely fulfilling the needs when phenomena related to the formation of black holes (BH), neutron stars (NS) and relativistic stars in general are concerned. Recently, mainly through the Vela, Beppo-SAX and Swift satellites, we reached a reasonable knowledge of the most violent events in the Universe and of some of the processes we believe are leading to the formation of black holes (BH). We plan to open a new window of opportunity to study the variegated physics of very fast astronomical transients, particularly the one related to extreme compact objects. The innovative approach is based on three cornerstones: 1) the design (the conceptual design has been already completed) of a 3m robotic telescope and related focal plane instrumentation characterized by the unique features: "No telescope ...

  4. An Automated Telescope for Education and Outreach

    Burks, G. S.; Guzik, T. G.; Tohline, J. E.; Landolt, A.

    1997-12-01

    In this time of limited resources, the problem of providing an up to date facility for education and outreach needs to be addressed. One solution to this problem is a joint venture between Louisiana State University, BREC (the Park and creation Commission of East Baton Rouge Parish), and BRAS (the Baton Rouge Astronomical Society). The result of this collaboration is a facility with outreach and educational space, a 20 inch Ritchey-Chretien telescope with CCD camera, and volunteers from the amateur community for help with the outreach mission. We present an overview of the project, and show how the telescope will be completely automated to allow use of the telescope by LSU students and our outreach partners on the Internet. We explore the possibility for use of this facility by a world wide audience over the web.

  5. An Overview of Extremely Large Telescopes Projects

    Carlberg, R G

    2005-01-01

    IAU Symposium 232 allows a snapshot of ELTs at a stage when design work in several critical mass projects has been seriously underway for two to three years. The status and som eof the main initial design choices are reviewed for the North American Giant Magellan Telescope (GMT) and the Thirty Meter Telescope (TMT) projects and the European Euro50 and the Overwhelmingly Large (OWL) projects. All the projects are drawing from the same "basket" of science requirements, although each project has somewhat different ambitions. The role of the project offices in creating the balance between project scope, timeline and cost, the "iron triangle" of project management, is emphasized with the OWL project providing a striking demonstration at this meeting. There is a reasonable case that the very broad range of science would be most effectively undertaken on several complementary telescopes.

  6. TCS software for the SONG telescope

    Wang, Hai; Ren, Changzhi

    2014-07-01

    Stellar Observations Network Group, SONG, is a Danish led international collaboration project to construct a global network of small 1m telescope around the globe. The second 1 meter SONG node telescope designed by NIAOT is installed at Delingha site in west China. TCS hardware is based on PC, UMAC, tape encoder, motor and driver. TCS software is developed in powerful Qt Creator environment under stable Debian 6.0 operation system. The design rules are modularity and simplification. Several software modules work together to realize telescope usual function . Tracking algorithm is comprised of two parts. One is UMAC motion program, another is tracking thread in PC program. Communication between TCS and OCS is complicated. The method to process remote command is described.

  7. Cooling Technology for Large Space Telescopes

    DiPirro, Michael; Cleveland, Paul; Durand, Dale; Klavins, Andy; Muheim, Daniella; Paine, Christopher; Petach, Mike; Tenerelli, Domenick; Tolomeo, Jason; Walyus, Keith

    2007-01-01

    NASA's New Millennium Program funded an effort to develop a system cooling technology, which is applicable to all future infrared, sub-millimeter and millimeter cryogenic space telescopes. In particular, this technology is necessary for the proposed large space telescope Single Aperture Far-Infrared Telescope (SAFIR) mission. This technology will also enhance the performance and lower the risk and cost for other cryogenic missions. The new paradigm for cooling to low temperatures will involve passive cooling using lightweight deployable membranes that serve both as sunshields and V-groove radiators, in combination with active cooling using mechanical coolers operating down to 4 K. The Cooling Technology for Large Space Telescopes (LST) mission planned to develop and demonstrate a multi-layered sunshield, which is actively cooled by a multi-stage mechanical cryocooler, and further the models and analyses critical to scaling to future missions. The outer four layers of the sunshield cool passively by radiation, while the innermost layer is actively cooled to enable the sunshield to decrease the incident solar irradiance by a factor of more than one million. The cryocooler cools the inner layer of the sunshield to 20 K, and provides cooling to 6 K at a telescope mounting plate. The technology readiness level (TRL) of 7 will be achieved by the active cooling technology following the technology validation flight in Low Earth Orbit. In accordance with the New Millennium charter, tests and modeling are tightly integrated to advance the technology and the flight design for "ST-class" missions. Commercial off-the-shelf engineering analysis products are used to develop validated modeling capabilities to allow the techniques and results from LST to apply to a wide variety of future missions. The LST mission plans to "rewrite the book" on cryo-thermal testing and modeling techniques, and validate modeling techniques to scale to future space telescopes such as SAFIR.

  8. Two VLT 8.2-m Unit Telescopes in Action

    1999-04-01

    -Res - JPEG: 1985 x 2148 pix - 2.0M] ESO PR Photo 19b/99 ESO PR Photo 19b/99 [Preview - JPEG: 400 x 478 pix - 165k] [Normal - JPEG: 800 x 956 pix - 594k] [High-Res - JPEG: 3000 x 3583 pix - 7.1M] Caption to PR Photo 19a/99 : This photo was obtained with VLT KUEYEN on April 4, 1999. It is reproduced from an excellent 60-second R(ed)-band exposure of the innermost region of a globular cluster, Messier 68 (NGC 4590) , in the southern constellation Hydra (The Water-Snake). The distance to this 8-mag cluster is about 35,000 light years, and the diameter is about 140 light-years. The excellent image quality is 0.38 arcsec , demonstrating a good optical and mechanical state of the telescope, already at this early stage of the commissioning phase. The field measures about 90 x 90 arcsec 2. The original scale is 0.0455 pix/arcsec and there are 2048x2048 pixels in one frame. North is up and East is left. Caption to PR Photo 19b/99 : This photo shows the central region of spiral galaxy ESO 269-57 , located in the southern constellation Centaurus at a distance of about 150 million light-years. Many galaxies are seen in this direction at about the same distance, forming a loose cluster; there are also some fainter, more distant ones in the background. The designation refers to the ESO/Uppsala Survey of the Southern Sky in the 1970's during which over 15,000 southern galaxies were catalogued. ESO 269-57 is a tightly bound object of type Sar , the "r" referring to the "ring" that surrounds the bright centre, that is overexposed here. The photo is a composite, based on three exposures (Blue - 600 sec; Yellow-Green - 300 sec; Red - 300 sec) obtained with KUEYEN on March 28, 1999. The image quality is 0.7 arcsec and the field is 90 x 90 arcsec 2. North is up and East is left. ESO PR Photo 19c/99 ESO PR Photo 19c/99 [Preview - JPEG: 400 x 478 pix - 132k] [Normal - JPEG: 800 x 956 pix - 446k] [High-Res - JPEG: 3000 x 3583 pix - 4.6M] ESO PR Photo 19d/99 ESO PR Photo 19d/99 [Preview - JPEG: 400 x

  9. Subsystems of the ISON Telescopes for GEO, HEO and LEO Observations

    Molotov, T.; Agapov, V.

    2012-09-01

    International Scientific Optical Network (ISON) represents one of largest systems specializing in observation of space objects. ISON project is continuously developing and is joining now the 27 observation facilities in 12 countries with 42 telescopes of different class (apertures from 12.5 cm to 2.6 m). 3.5 millions of measurements in 450 thousands of tracks are collected for about 3000 objects in 2011. 168 new high-orbits objects are discovered during 2011 and orbits for 1704 GEO region objects are maintained in the ISON database. Three ISON subsystems are formed - for survey observations of bright objects at GEO-region; ephemerides observations of high-orbit faint fragments and ephemerides observations of bright GEO and HEO objects. Two more subsystems are in development - for surveying the HEO-objects and observations of LEO-objects. Few series of dedicated telescopes with large FOV and automated mounts were elaborated for them. Ten 22-cm aperture instruments with FOV of 4° and four 25-cm aperture instruments with FOV of 3° were installed in observing facilities around the World in order to survey the GEO region in global scale both by longitude (0°-360°) and inclination (0°-20°) and provide main data stream for the orbital archive maintenance. First unites of 40-cm and 50-cm aperture instruments with FOV of 2° were produced for the surveying and tracking observations of faint objects (first such telescopes are installed in Kitab, Ussuriysk and Kislovodsk). Lot of 19.2-cm aperture instruments with FOV of 7° is produced and in installation now for surveying the HEO-objects, including double and quadruple systems with more large FOV (first such telescopes are installed in Sanglok and Kislovodsk) . Four 12.5-cm aperture instruments with FOV of 10° will be used for LEO-objects observations (first such telescope is installed in Tiraspol). It was elaborated and tested few survey modes and algorithm permitting to find correlation between short arc tracks of

  10. Performance of a time-of-flight silicon strip telescope in the temperature range 20 C to -55 C

    Codino, A. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Brunetti, M.T. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Federico, C. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Grimani, C. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Macchiaiolo, T. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Menichelli, M. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Minelli, G. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Miozza, M. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Plouin, F. [Laboratoire National Saturne, Gif-Sur-Yvette, Saclay (France)

    1995-10-15

    A cold silicon strip telescope for time-of-flight determination operating at -55 C has been tested using a hadron beam at Saturne II, Saclay. We present performance tests of the telescope, the time-of-flight distributions between pairs of silicon hodoscopes and their dependence on temperature. A detailed description of the apparatus, the refrigerator system and the calibration procedures is also reported. A linear relationship between the time resolution and the temperature of the apparatus is measured. An improvement of a factor 2 in the time-of-flight resolution is observed when the temperature decreases from +20 C to -55 C. (orig.).

  11. Performance of a time-of-flight silicon strip telescope in the temperature range 20 C to -55 C

    A cold silicon strip telescope for time-of-flight determination operating at -55 C has been tested using a hadron beam at Saturne II, Saclay. We present performance tests of the telescope, the time-of-flight distributions between pairs of silicon hodoscopes and their dependence on temperature. A detailed description of the apparatus, the refrigerator system and the calibration procedures is also reported. A linear relationship between the time resolution and the temperature of the apparatus is measured. An improvement of a factor 2 in the time-of-flight resolution is observed when the temperature decreases from +20 C to -55 C. (orig.)

  12. VERITAS Telescope 1 Relocation: Details and Improvements

    Perkins, Jeremy S

    2009-01-01

    The first VERITAS telescope was installed in 2002-2003 at the Fred Lawrence Whipple Observatory and was originally operated as a prototype instrument. Subsequently the decision was made to locate the full array at the same site, resulting in an asymmetric array layout. As anticipated, this resulted in less than optimal sensitivity due to the loss in effective area and the increase in background due to local muon initiated triggers. In the summer of 2009, the VERITAS collaboration relocated Telescope 1 to improve the overall array layout. This has provided a 30% improvement in sensitivity corresponding to a 60% change in the time needed to detect a source.

  13. Fermi Large Area Telescope first source catalog

    2010-01-01

    We present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), during the first 11 months of the science phase of the mission, which began on 2008 August 4. The First Fermi-LAT catalog (1FGL) contains 1451 sources detected and characterized in the 100 MeV to 100 GeV range. Source detection was based on the average flux over the 11-month period, and the threshold likelihood Test St...

  14. Fermi Large Area Telescope Third Source Catalog

    The Fermi-LAT Collaboration

    2015-01-01

    We present the third Fermi Large Area Telescope source catalog (3FGL) of sources in the 100 MeV-300 GeV range. Based on the first four years of science data from the Fermi Gamma-ray Space Telescope mission, it is the deepest yet in this energy range. Relative to the 2FGL catalog, the 3FGL catalog incorporates twice as much data as well as a number of analysis improvements, including improved calibrations at the event reconstruction level, an updated model for Galactic diffuse gamma-ray emissi...

  15. FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG

    Nolan, P. L.; Abdo, A. A.; Ackermann et al., M.

    2012-01-01

    We present the second catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24 months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24-month period. The Second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% conf...

  16. Multiple-mirror telescope systems in astronomy

    The function of a telescope is to optimize the transfer of the information of interest from a source of finite angular size to the analytical device which is going to extract it. It is far from obvious that the conventional large telescope is the optimum fore-optical system for looking through a turbulent atmosphere. There are considerable scientific and financial advantages in going to multiple-imaging-elements and several groups in different parts of the world are working in this direction. (orig.)

  17. Searching for tau neutrinos with Cherenkov telescopes

    Gora, D.; Bernardini, E.; Kappes, A.

    2015-01-01

    Cherenkov telescopes have the capability of detecting high energy tau neutrinos in the energy range of 1--1000 PeV by searching for very inclined showers. If a tau lepton, produced by a tau neutrino, escapes from the Earth or a mountain, it will decay and initiate a shower in the air which can be detected by an air shower fluorescence or Cherenkov telescope. In this paper, we present detailed Monte Carlo simulations of corresponding event rates for the VERITAS and two proposed Cherenkov Teles...

  18. DESTINY, The Dark Energy Space Telescope

    Pasquale, Bert A.; Woodruff, Robert A.; Benford, Dominic J.; Lauer, Tod

    2007-01-01

    We have proposed the development of a low-cost space telescope, Destiny, as a concept for the NASA/DOE Joint Dark Energy Mission. Destiny is a 1.65m space telescope, featuring a near-infrared (0.85-1.7m) survey camera/spectrometer with a moderate flat-field field of view (FOV). Destiny will probe the properties of dark energy by obtaining a Hubble diagram based on Type Ia supernovae and a large-scale mass power spectrum derived from weak lensing distortions of field galaxies as a function of redshift.

  19. Young Astronomers' Observe with ESO Telescopes

    1995-11-01

    Today, forty 16-18 year old students and their teachers are concluding a one-week, educational `working visit' to the ESO Headquarters in Garching (See ESO Press Release 14/95 of 8 November 1995). They are the winners of the Europe-wide contest `Europe Towards the Stars', organised by ESO with the support of the European Union, under the auspices of the Third European Week for Scientific and Technological Culture. From November 14-20, they have worked with professional ESO astronomers in order to get insight into the methods and principles of modern astronomy and astrophysics, as carried out at one of the world's foremost international centres. This included very successful remote observations with the ESO 3.5-m New Technology Telescope (NTT) and the 1.4-m Coude Auxiliary Telescope (CAT) via a satellite link between the ESO Headquarters and the La Silla observatory in Chile, 12,000 kilometres away. After a general introduction to modern astronomy on the first day of the visit, the participants divided into six teams, according to their interests. Some chose to observe distant galaxies, others prefered to have a closer look on binary stars, and one team decided to investigate a star which is thought to be surrounded by a proto-planetary system. Each team was supported by an experienced ESO astronomer. Then followed the observations at the remote consoles during three nights, the first at the NTT and the following at the CAT. Each team had access to the telescope during half a night. Although the work schedule - exactly as in `real' science - was quite hard, especially during the following data reduction and interpretative phase, all teams managed extremely well and in high spirits. The young astronomers' observations were favoured by excellent atmospheric conditions. At the NTT, the seeing was better than 0.5 arcsecond during several hours, an exceptional value that allows very good images to be obtained. All observations represent solid and interesting science, and

  20. Distributed multiple description coding

    Bai, Huihui; Zhao, Yao

    2011-01-01

    This book examines distributed video coding (DVC) and multiple description coding (MDC), two novel techniques designed to address the problems of conventional image and video compression coding. Covering all fundamental concepts and core technologies, the chapters can also be read as independent and self-sufficient, describing each methodology in sufficient detail to enable readers to repeat the corresponding experiments easily. Topics and features: provides a broad overview of DVC and MDC, from the basic principles to the latest research; covers sub-sampling based MDC, quantization based MDC,

  1. Description logic rules

    Krötzsch, M

    2010-01-01

    Ontological modelling today is applied in many areas of science and technology,including the Semantic Web. The W3C standard OWL defines one of the most important ontology languages based on the semantics of description logics. An alternative is to use rule languages in knowledge modelling, as proposed in the W3C's RIF standard. So far, it has often been unclear how to combine both technologies without sacrificing essential computational properties. This book explains this problem and presents new solutions that have recently been proposed. Extensive introductory chapters provide the necessary

  2. A. Variable descriptions

    Hohmann, Sebastian

    2012-01-01

    The appendix lists all variables, or component variables in the case of the institutional variables w and s, together with sources. Detailed descriptions, the wording of which is taken, if possible, directly from the original sources, are also given. Economic variables – dependent name:external_debt_cris source: Reinhart, Camen M. and Kenneth S. Rogoff, From Financial Crash to Debt Crisis, NBER Working Paper 15795, March 2010. Forthcoming in American Economic Review http://terpconnect.umd.edu...

  3. 4 m Davies-Cotton telescope for the Cherenkov Telescope Array

    Moderski, R; Barnacka, A; Basili, A; Boccone, V; Bogacz, L; Cadoux, F; Christov, A; Della Volpe, M; Dyrda, M; Frankowski, A; Grudzińska, M; Janiak, M; Karczewski, M; Kasperek, J; Kochański, W; Korohoda, P; Kozioł, J; Lubiński, P; Ludwin, J; Lyard, E; Marszałek, A; Michałowski, J; Montaruli, T; Nicolau-Kukliński, J; Niemiec, J; Ostrowski, M; Płatos, Ł; Rajda, P J; Rameez, M; Romaszkan, W; Rupiński, M; Seweryn, K; Stodulska, M; Stodulski, M; Walter, R; Winiarski, K; Wiśniewski, Ł; Zagdański, A; Zietara, K; Ziółkowski, P; Żychowski, P

    2013-01-01

    The Cherenkov Telescope Array (CTA) is the next generation very high energy gamma-ray observatory. It will consist of three classes of telescopes, of large, medium and small sizes. The small telescopes, of 4 m diameter, will be dedicated to the observations of the highest energy gamma-rays, above several TeV. We present the technical characteristics of a single mirror, 4 m diameter, Davies-Cotton telescope for the CTA and the performance of the sub-array consisting of the telescopes of this type. The telescope will be equipped with a fully digital camera based on custom made, hexagonal Geiger-mode avalanche photodiodes. The development of cameras based on such devices is an RnD since traditionally photomultipliers are used. The photodiodes are now being characterized at various institutions of the CTA Consortium. Glass mirrors will be used, although an alternative is being considered: composite mirrors that could be adopted if they meet the project requirements. We present a design of the telescope structure,...

  4. Three new alternative splicing variants of human cytochrome P450 2D6 mRNA in human extratumoral liver tissue

    Jian Zhuge; Ying-Nian Yu

    2004-01-01

    AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing.METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcription-polymerase chain reaction (RT-PCR) from a human extratumoral liver tissue and cloned into pGEM-T vector. The cDNA was sequenced.Exons from 1 to 4 of human CYP2D6 cDNAs were also amplificated by RT-PCR from extratumoral liver tissues of17 human hepatocellular carcinomas. Some RT-PCR products were sequenced. Exons 1 to 4 of CYP2D6 gene were amplified by PCR from extratumoral liver tissue DNA.Two PCR products from extratumoral liver tissues expressing skipped mRNA were partially sequenced.RESULTS: One of the CYP2D6cDNAs had 470 nucleotides from 79 to 548 (3' portion of exons 1 to 5' portion of exon 4),and was skipped. Exons 1 to 4 of CYP2D6 cDNA were assayed with RT-PCR in 17 extratumoral liver tissues. Both wild type and skipped mRNAs were expressed in 4 samples,only wild type mRNA was expressed in 5 samples, and only skipped mRNA was expressed in 8 samples. Two more variants were identified by sequencing the RT-PCR products of exons 1 to 4 of CYP2D6cDNA. The second variant skipped 411 nucleotides from 175 to 585. This variant was identified in 4 different liver tissues by sequencing the RT-PCR products. We sequenced partially 2 of the PCR products amplified of CYP2D6 exon 1 to exon 4 from extratumoral liver tissue genomic DNA that only expressed skipped mRNA by RT-PCR. No point mutations around exon 1, intron 1, and exon 4, and no deletion in CYP2D6gene were detected. The third variant was the skipped exon 3, and 153 bp was lost.CONCLUSION: Three new alternative splicing variants of CYP2D6 mRNA have been identified. They may not be caused by gene mutation and may lose CYP2D6 activity and act as a down-regulator of CYP2D6.

  5. Hydrogen storage properties of LaMgNi{sub 3.6}M{sub 0.4} (M = Ni, Co, Mn, Cu, Al) alloys

    Yang, Tai [Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081 (China); Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010 (China); Zhai, Tingting; Yuan, Zeming; Bu, Wengang [Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081 (China); Xu, Sheng [Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010 (China); Zhang, Yanghuan, E-mail: zhangyh59@sina.com [Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081 (China); Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010 (China)

    2014-12-25

    Highlights: • La–Mg–Ni system AB{sub 2}-type alloys were prepared by induction melting. • Structures and lattice parameters were analysed by XRD. • Hydrogen absorption/desorption performances were studied. • Mechanisms of hydrogen absorption capacity fading were investigated. - Abstract: LaMgNi{sub 3.6}M{sub 0.4} (M = Ni, Co, Mn, Cu, Al) alloys were prepared through induction melting process. The phase compositions and crystal structures were characterised via X-ray diffraction (XRD). The hydrogen storage properties, including activation performance, hydrogen absorption capacity, cycle stability, alloy particle pulverisation and plateau pressure, were systemically investigated. Results show that Ni, Co, Mn and Cu substitution alloys exhibit multiphase structures comprising the main phase LaMgNi{sub 4} and the secondary phase LaNi{sub 5}. However, the secondary phase of the Al substitution alloy changes into LaAlNi{sub 4}. The lattice parameters and cell volumes of the LaMgNi{sub 4} phase follow the order Ni < Co < Al < Cu < Mn. Activation is simplified through partial substitution of Ni with Al, Cu and Co. The hydrogen absorption capacities of all of the alloys are approximately 1.7 wt.% at the first activation process; however, they rapidly decrease with increasing cycle number. In addition, the stabilities of hydriding and dehydriding cycles decrease in the order Al > Co > Ni > Cu > Mn. Hydriding processes result in numerous cracks and amorphisation of the LaMgNi{sub 4} phase in the alloys. The p–c isotherms were determined by a Sieverts-type apparatus. Two plateaus were observed for the Ni, Co and Al substitution alloys, whereas only one plateau was found for Mn and Cu. This result was caused by the amorphisation of the LaMgNi{sub 4} phase during the hydriding cycles. Reversible absorption and desorption of hydrogen are difficult to achieve. Substitutions of Ni with Co, Mn, Cu and Al significantly influence the reduction of hysteresis between

  6. Prototype of the SST-1M Telescope Structure for the Cherenkov Telescope Array

    Niemiec, J; Błocki, J; Bogacz, L; Borkowski, J; Bulik, T; Cadoux, F; Christov, A; Curyło, M; della Volpe, D; Dyrda, M; Favre, Y; Frankowski, A; Grudnik, Ł; Grudzińska, M; Heller, M; Idźkowski, B; Jamrozy, M; Janiak, M; Kasperek, J; Lalik, K; Lyard, E; Mach, E; Mandat, D; Marszałek, A; Michałowski, J; Moderski, R; Montaruli, T; Neronov, A; Ostrowski, M; Paśko, P; Pech, M; Porcelli, A; Prandini, E; Rajda, P; Rameez, M; Schioppa, E jr; Schovanek, P; Seweryn, K; Skowron, K; Sliusar, V; Sowiński, M; Stawarz, Ł; Stodulska, M; Stodulski, M; Pujadas, I Troyano; Toscano, S; Walter, R; Wiȩcek, M; Zagdański, A; Ziȩtara, K

    2015-01-01

    A single-mirror small-size (SST-1M) Davies-Cotton telescope with a dish diameter of 4 m has been built by a consortium of Polish and Swiss institutions as a prototype for one of the proposed small-size telescopes for the southern observatory of the Cherenkov Telescope Array (CTA). The design represents a very simple, reliable, and cheap solution. The mechanical structure prototype with its drive system is now being tested at the Institute of Nuclear Physics PAS in Krakow. Here we present the design of the prototype and results of the performance tests of the structure and the drive and control system.

  7. Silicon Photomultiplier Research and Development Studies for the Large Size Telescope of the Cherenkov Telescope Array

    Rando, Riccardo; Corti, Daniele; Dazzi, Francesco; de Angelis, Alessandro; Dettlaff, Antonios; Dorner, Daniela; Fink, David; Fouque, Nadia; Grundner, Felix; Haberer, Werner; Hahn, Alexander; Hermel, Richard; Korpar, Samo; Mezek, Gašper Kukec; Maier, Ronald

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the the next generation facility of imaging atmospheric Cherenkov telescopes; two sites will cover both hemispheres. CTA will reach unprecedented sensitivity, energy and angular resolution in very-high-energy gamma-ray astronomy. Each CTA array will include four Large Size Telescopes (LSTs), designed to cover the low-energy range of the CTA sensitivity ($\\sim$20 GeV to 200 GeV). In the baseline LST design, the focal-plane camera will be instrumented with...

  8. SST-GATE: A dual mirror telescope for the Cherenkov Telescope Array

    Zech, A.; Amans, J.-P.; Blake, S; Boisson, C.; Costille, C.; De-Frondat, F.; Dournaux, J. -L.; Dumas, D.; Fasola, G.; T. Greenshaw; Hervet, O.; Huet, J. -M.; Laporte, P.; Rulten, C.; Savoie, D.

    2013-01-01

    The Cherenkov Telescope Array (CTA) will be the world's first open observatory for very high energy gamma-rays. Around a hundred telescopes of different sizes will be used to detect the Cherenkov light that results from gamma-ray induced air showers in the atmosphere. Amongst them, a large number of Small Size Telescopes (SST), with a diameter of about 4 m, will assure an unprecedented coverage of the high energy end of the electromagnetic spectrum (above ~1TeV to beyond 100 TeV) and will ope...

  9. Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO{sub 4} at 303 K; Determinacion de las constantes de hidrolisis del Europio (III), en medios de fuerza ionica 4, 5 y 6 M de NaClO{sub 4} a 303 K

    Alvarado B, A.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pC{sub H} values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

  10. Study on fault diagnose expert system for large astronomy telescope

    Liu, Jia-jing; Luo, Ming-Cheng; Tang, Peng-yi; Wu, Wen-qing; Zhang, Guang-yu; Zhang, Hong-fei; Wang, Jian

    2014-08-01

    The development of astronomical techniques and telescopes currently entered a new vigorous period. The telescopes have trends of the giant, complex, diversity of equipment and wide span of control despite of optical, radio space telescopes. That means, for telescope observatory, the control system must have these specifications: flexibility, scalability, distributive, cross-platform and real-time, especially the fault locating and fault processing is more important when fault or exception arise. Through the analysis of the structure of large telescopes, fault diagnosis expert system of large telescope based on the fault tree and distributed log service is given.

  11. Structure Model Analysis of the Kashima 34m Telescope

    Nakajima, Junichi; Nakamura, Toshio; Saita, Takeshi; Horiguchi, Junji; Yuge, Kouhei

    2001-03-01

    Deformation analysis of the Kashima 34-m radio telescope is performed. Although the telescope has a large aperture and accurate reflector panels, the dish support structures determine the high-frequency performance. Especially in millimeter wavelength, deformations above 1-mm affect the telescope efficiency seriously. We have modeled 34-m telescopes into elements and used a finite element method FEM to simulate accurate telescope deformations. The first results we obtained agreed well with the realistic deformation. Future analysis and telescope evaluations based on computer simulations are possible with this FEM model.

  12. VISTA Telescope opto-mechanical integration

    Jeffers, Paul; Henry, David

    2010-07-01

    VISTA1 is an infrared survey telescope which delivers 0.5 arc second images over a 1.65 degree diameter unvignetted field of view. The project was split into separate work-packages, which after successful individual acceptance, were integrated by the project office. The main mechanical integration is the matching up of two sides of a controlled interface and should be a straightforward process. This covers the mounting of the M2 Hexapod, the installation of the M2 mirror assembly onto the M2 Hexapod, the M1 attachment to the M1 support system components and installation of the instrument mass simulator. The second stage of this integration is the mechanical alignment of the optical elements (i.e. M1 & M2) to the telescope mechanical axis. This is achieved through use of jigs and alignment equipment combined with the inbuilt adjustment in both the M2 on it's Hexapod and the manual adjustment of the M1 on its positional definers. This then leaves the telescope in a state ready to start optical commissioning using a Shack Hartman wavefront sensor. This paper deals with the mechanical integration and alignment of the telescope components up to the start of optical commissioning. There will be discussion of the build-up of information through the separate component acceptance details, to the equipment methodology, preparation and actual integration of the different systems. There will also be discussion of lessons learned.

  13. Searching for tau neutrinos with Cherenkov telescopes

    Gora, D; Kappes, A

    2014-01-01

    Cherenkov telescopes have the capability of detecting high energy tau neutrinos in the energy range of 1--1000 PeV by searching for very inclined showers. If a tau lepton, produced by a tau neutrino, escapes from the Earth or a mountain, it will decay and initiate a shower in the air which can be detected by an air shower fluorescence or Cherenkov telescope. In this paper, we present detailed Monte Carlo simulations of corresponding event rates for the VERITAS and two proposed Cherenkov Telescope Array sites: Meteor Crater and Yavapai Ranch, which use representative AGN neutrino flux models and take into account topographic conditions of the detector sites. The calculated neutrino sensitivities depend on the observation time and the shape of the energy spectrum, but in some cases are comparable or even better than corresponding neutrino sensitivities of the IceCube detector. For VERITAS and the considered Cherenkov Telescope Array sites the expected neutrino sensitivities are up to factor 3 higher than for th...

  14. The Lake Baikal telescope NT-36

    Since April 13th, 1993 the underwater Cherenkov telescope NT-36 consisting of 36 photomultipliers attached to 3 strings, is operated in lake Baikal. We describe this first stationary underwater multistring array and present results from the first months of operation. (orig.)

  15. Go-To Telescopes Under Suburban Skies

    Monks, Neale

    2010-01-01

    For the last four centuries stargazers have turned their telescopes to the night skies to look at its wonders, but only in this age of computers has it become possible to let the telescope find for you the object you are looking for! So-called “go-to” telescopes are programmed with the locations of thousands of objects, including dazzling distant Suns, stunning neighboring galaxies, globular and open star clusters, the remnants of past supernovae, and many other breathtaking sights. This book does not tell you how to use your Go-to telescope. Your manual will help you do that. It tells you what to look for in the deep sky and why, and what equipment to best see it with. Organized broadly by what is best for viewing in the northern hemisphere in different seasons, Monks further divides the sights of each season into groupings such as “Showpiece Objects,” “Interesting Deep Sky Objects,” and “Obscure and Challenging Deep Sky Objects.” He also tells what objects are visible even in light-polluted ...

  16. Choosing and Using a Refracting Telescope

    English, Neil

    2011-01-01

    The refracting telescope has a long and illustrious past. Here’s what the author says about early telescopes and today’s refractors: “Four centuries ago, a hitherto obscure Italian scientist turned a home-made spyglass towards the heavens. The lenses he used were awful by modern standards, inaccurately figured and filled with the scars of their perilous journey from the furnace to the finishing workshop. Yet, despite these imperfections, they allowed him to see what no one had ever seen before – a universe far more complex and dynamic than anyone had dared imagine. But they also proved endlessly useful in the humdrum of human affairs. For the first time ever, you could spy on your neighbor from a distance, or monitor the approach of a war-mongering army, thus deciding the fate of nations. “The refractor is without doubt the prince of telescopes. Compared with all other telescopic designs, the unobstructed view of the refractor enables it to capture the sharpest, highest contrast images and the wides...

  17. The ANTARES telescope neutrino alert system

    Ageron, M.; Aguilar, J. A.; Al Samarai, I.; Albert, A.; Andre, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Jesus, A. C. Assis; Astraatmadja, T.; Aubert, J. -J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Carloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, Ph.; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Curtil, C.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhoefer, A.; Ernenwein, J-P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J-L.; Galata, S.; Gay, P.; Giacomelli, G.; Giordano, V.; Gomez-Gonzalez, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A. J.; Hello, Y.; Hernandez-Rey, J. J.; Herold, B.; Hoessl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lefevre, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Palioselitis, D.; Pavalas, G. E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Richardt, C.; Richter, R.; Riviere, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Salesa, F.; Sapienza, P.; Schoeck, F.; Schuller, J-P.; Schuessler, F.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Sanchez-Losa, A.; Taiuti, M.; Tamburini, C.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zuniga, J.

    2012-01-01

    The ANTARES telescope has the capability to detect neutrinos produced in astrophysical transient sources. Potential sources include gamma-ray bursts, core collapse supernovae, and flaring active galactic nuclei. To enhance the sensitivity of ANTARES to such sources, a new detection method based on c

  18. Review of the solar array telescopes

    Smith, D. A.

    2005-01-01

    For several years the only experiments sensitive to astrophysical gamma rays with energies beyond the reach of EGRET but below that the Cherenkov imaging telescopes have been the "solar towar" detectors. They use > 2000 m$^{2}$ mirror areas to sample the Cherenkov wavefront generated by

  19. Imaging capabilities of the SODART telescopes

    Christensen, Finn Erland; Hornstrup, Allan; Pedersen, Kristian; Frederiksen, Peter; Westergaard, Niels Jørgen Stenfeldt

    The on- and off-axis imaging properties and effective area of the two SODART flight telescopes have been measured using the expanded beam X-ray facility at the Daresbury synchrotron. Following measurements have been done for both Flight Model 1 & 2, at three energies: 6.627 keV, 8.837 keV and 11...

  20. The telescope conjecture for semihereditary commutative rings

    Bazzoni, Silvana

    2013-01-01

    The paper has been withdrawn, since there is a mistake in Proposition 5.2. The result on the telescope conjecture for semihereditary rings is correct, but the characterization of the smashing subcategories of the derived category of commutative rings is not complete.

  1. The GREGOR Solar Telescope on Tenerife

    Schmidt, W.; von der Lühe, O.; Volkmer, R.; Denker, C.; Solanki, S.K.; Balthasar, H.; Bello González, N.; Berkefeld, T.; Collados Vera, M.; Hofmann, A.; Kneer, F.; Lagg, A.; Puschmann, K.G.; Schmidt, D.; Sobotka, Michal; Soltau, D.; Strassmeier, K.G.

    San Francisco : Astronomical Society otf the Pacific, 2012 - (Rimmele, T.), s. 365-376 ISBN 9781583818084. - (ASP Conference Series. 463). [ATST - EAST Workshop in Solar Physics /2./. Washington (US), 09.11.2011-11.11.2011] Institutional support: RVO:67985815 Keywords : telescope GREGOR * configuration Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  2. Teaching with Internet Telescopes: Some Lessons Learned

    Stencel, Robert

    Observational astronomy is often difficult for pre-college students and teachers because: (1) school occurs in daytime and visual observing at night; (2) light pollution hides the stars from students living in cities; (3) few schools have teachers trained to use and maintain astronomy equipment; (4) there is lack of access to expertise when needed; (5) physically disabled students cannot easily access a telescope eypiece. Internet access to computer controlled telescopes with digital cameras can solve many of these difficulties. The Web enables students and teachers to access well-maintained internet-controllable telescopes at dark-site locations and to consult more readily with experts. This paper reports on a three-month pilot project exploring this situation conducted Feb-May 2002 which allowed high school students to access a CCD-equipped accurately-pointing and tracking telescope located in New Mexico controllable over the Web with a user-friendly skymap browser tool. User interest proved phenomenal and user statistics proved diverse. There were distinct lessons learned about how to enhance student participation in the research process. Details available at website www.du.edu/~rstencel/stn.htm. We thank the ICSRC for a grant to Denver University and acknowledge in-kind support from the estate of William Herschel Womble.

  3. Telescope-sipping in PWR plants

    Based on the experience gathered in the beginning of the 70s, ABB Atom has introduced an improved fuel leak detection system, the Telescope Sipping. A successful pilot test of this sytem was carried out in November 1996 on selected fuel assemblies at Grohnde nuclear power plant. (orig.)

  4. Pulsar Observations with Radio Telescope FAST

    Nan, Ren-Dong; Wang, Qi-Ming; Zhu, Li-Chun; Zhu, Wen-Bai; Jin, Cheng-Jin; Gan, Heng-Qian

    2006-12-01

    FAST, Five hundred meter Aperture Spherical Telescope, is the Chinese effort for the international project SKA, Square Kilometer Array. An innovative engineering concept and design pave a new road to realizing huge single dish in the most effective way. Three outstanding features of the telescope are the unique karst depressions as the sites, the active main reflector which corrects spherical aberration on the ground to achieve full polarization and wide band without involving complex feed system, and the light focus cabin driven by cables and servomechanism plus a parallel robot as secondary adjustable system to carry the most precise parts of the receivers. Besides a general coverage of those critical technologies involved in FAST concept, the progresses in demonstrating model being constructed at the Miyun Radio Observatory of the NAOC is introduced. Being the most sensitive radio telescope, FAST will enable astronomers to jumpstart many of science goals, for example, the natural hydrogen line surveying in distant galaxies, looking for the first generation of shining objects, hearing the possible signal from other civilizations, etc. Among these subjects, the most striking one could be pulsar study. Large scale survey by FAST will not only improve the statistics of the pulsar population, but also may offer us a good fortune to pick up more of the most exotic, even unknown types like a sub-millisecond pulsar or a neutron star -- black hole binary as the telescope is put into operation.

  5. Modeling and control of antennas and telescopes

    Gawronski, Wodek

    2008-01-01

    The book shows, step-by-step, the design, implementation, and testing of the antenna/telescope control system, from the design stage (analytical model) to fine tuning of the RF beam pointing (monopulse and conscan). It includes wide use of Matlab and Simulink..

  6. Thirty meter telescope observatory software architecture

    The Thirty Meter Telescope (TMT) will be a ground-based, 30-m optical-IR telescope with a highly segmented primary mirror located on the summit of Mauna Kea in Hawaii. The TMT Observatory Software (OSW) system will deliver the software applications and infrastructure necessary to integrate all TMT software into a single system and implement a minimal end-to-end science operations system. At the telescope, OSW is focused on the task of integrating and efficiently controlling and coordinating the telescope, adaptive optics, science instruments, and their subsystems during observation execution. From the software architecture viewpoint, the software system is viewed as a set of software components distributed across many machines that are integrated using a shared software base and a set of services that provide communications and other needed functionality. This paper describes the current state of the TMT Observatory Software focusing on its unique requirements, architecture, and the use of middle-ware technologies and solutions that enable the OSW design. (authors)

  7. XSPECT telescopes on the SRG: optical performance

    Westergaard, Niels Jørgen Stenfeldt; Polny, Josef; Christensen, Finn Erland; Nørgaard-Nielsen, Hans Ulrik; Schnopper, Herbert W.

    1994-01-01

    The XSPECT, thin foil, multiply nested telescope on SRG has been designed to achieve a large effective area at energies between 6 and 15 keV. The design goal for the angular resolution is 2 arcmin (HPD). Results of foil figure error measurements are presented. A ray tracing analysis was performed...

  8. The Science and Art of Using Telescopes

    Pugh, Philip

    2009-01-01

    Explains how to select equipment that is at the 'next level', and describes how to use more advanced telescopes and accessories. This book includes a section on imaging and equipment that range from regular digital cameras, through web cams, to specialized chilled-chip CCD cameras

  9. Hydrodynamic experiments on dacryoconarid shell telescoping

    Hladil, Jindřich; Šimčík, Miroslav; Růžička, Marek; Kulaviak, Lukáš; Lisý, Pavel

    2014-01-01

    Roč. 47, č. 3 (2014), s. 376-396. ISSN 0024-1164 R&D Projects: GA ČR GAP210/10/2351 Institutional support: RVO:67985831 ; RVO:67985858 Keywords : dacryoconarid shells * experimental fluid mechanics * narrow cones * Palaeozoic * telescoping Subject RIV: DB - Geology ; Mineralogy; CI - Industrial Chemistry, Chemical Engineering (UCHP-M) Impact factor: 1.454, year: 2014

  10. Fundamental and exotic physics with Cherenkov telescopes

    De Angelis, A., E-mail: alessandro.de.angelis@cern.c [Dipartimento di Fisica dell' Universita di Udine and INFN, Udine (Italy); De Lotto, B. [Dipartimento di Fisica dell' Universita di Udine and INFN, Udine (Italy); Roncadelli, M. [INFN Pavia (Italy)

    2011-02-21

    The detection of high-energy {gamma} rays from astrophysical sources, using the Fermi/LAT detector and in the very-high-energy limit the Cherenkov telescopes MAGIC, H.E.S.S. and VERITAS, can provide tests of fundamental physics with unprecedented sensitivity, and possibly allows to probe new and exotic scenarios.

  11. The Atacama Cosmology Telescope: Data Characterization and Map Making

    Duenner, Rolando; Hasselfield, Matthew; Marriage, Tobias A.; Sievers, Jon; Acquaviva, Viviana; Addison, Graeme E.; Ade, Peter A. R.; Aguirre, Paula; Amiri, Mandana; Appel, John William; Barrientos, L. Felipe; Battistelli, Elia S.; Bond, J. Richard; Brown, Ben; Burger, Bryce; Chervenak, Jay; Calabrese, Erminia; Das, Sudeep; Devlin, Mark J.; Dicker, Simon R.; Doriese, W. Bertrand; Dunkley, Joanna; Essinger-Hileman, Thomas; Moseley, Harvey; Wollack, Ed

    2012-01-01

    We present a description of the data reduction and mapmaking pipeline used for the 2008 observing season of the Atacama Cosmology Telescope (ACT). The data presented here at 148 GHz represent 12% or the 90 TB collected by ACT from 2007 to 2010. In 2008 we observed for 136 days, producing a total of 142h of data (11 TB for the 148 GHz band only), with a daily average of 10.5 h of observation. From these, 108.5 h were devoted to 850 sq deg stripe (11.2 h by 9 deg.1) centered on a declination of -52 deg.7, while 175 h were devoted to a 280 square deg stripe (4.5 h by 4 deg.8) centered at the celestial equator. We discuss sources of statistical and systematic noise, calibration, telescope pointing and data selection. Out of 1260 survey hours and 1024 detectors per array, 816 h and 593 effective detectors remain after data selection for this frequency band, yielding a 38 % survey efficiency. The total sensitivity in 2008, determined from the noise level between 5 Hz and 20 Hz in the time-ordered data stream (TOD), is 32 muK square root of s in CMB units. Atmospheric brightness fluctuations constitute the main contaminant in the data and dominate the detector and noise covariance at low frequencies in the TOD. The maps were made by solving the lease squares problem using the Preconditioned Conjugate Gradient method, incorporating the details of the detector and noise correlations. Cross-correlation with WMAP sky maps as well as analysis from simulations reveal the our maps are unbiased at l > 300. This paper accompanies the public release of the 148 GHz southern stripe maps from 2008. The techniques described here will be applied to future maps and data releases.

  12. THE ATACAMA COSMOLOGY TELESCOPE: DATA CHARACTERIZATION AND MAPMAKING

    Duenner, Rolando; Aguirre, Paula; Barrientos, L. Felipe [Departamento de Astronomia y Astrofisica, Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Hasselfield, Matthew; Amiri, Mandana; Battistelli, Elia S.; Burger, Bryce [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z4 (Canada); Marriage, Tobias A.; Acquaviva, Viviana; Das, Sudeep [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States); Sievers, Jon; Appel, John William [Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544 (United States); Addison, Graeme E.; Calabrese, Erminia [Department of Astrophysics, Oxford University, Oxford OX1 3RH (United Kingdom); Ade, Peter A. R. [School of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA (United Kingdom); Bond, J. Richard [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada); Brown, Ben [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Chervenak, Jay [Code 553/665, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Devlin, Mark J.; Dicker, Simon R. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); and others

    2013-01-01

    We present a description of the data reduction and mapmaking pipeline used for the 2008 observing season of the Atacama Cosmology Telescope (ACT). The data presented here at 148 GHz represent 12% of the 90 TB collected by ACT from 2007 to 2010. In 2008 we observed for 136 days, producing a total of 1423 hr of data (11 TB for the 148 GHz band only), with a daily average of 10.5 hr of observation. From these, 1085 hr were devoted to an 850 deg{sup 2} stripe (11.2 hr by 9. Degree-Sign 1) centered on a declination of -52. Degree-Sign 7, while 175 hr were devoted to a 280 deg{sup 2} stripe (4.5 hr by 4. Degree-Sign 8) centered at the celestial equator. The remaining 163 hr correspond to calibration runs. We discuss sources of statistical and systematic noise, calibration, telescope pointing, and data selection. For the 148 GHz band, out of 1260 survey hours and 1024 detectors in the array, 816 hr and 593 effective detectors remain after data selection, yielding a 38% survey efficiency. The total sensitivity in 2008, determined from the noise level between 5 Hz and 20 Hz in the time-ordered data stream (TOD), is 32 {mu}K{radical}s in cosmic microwave background units. Atmospheric brightness fluctuations constitute the main contaminant in the data and dominate the detector noise covariance at low frequencies in the TOD. The maps were made by solving the least-squares problem using the Preconditioned Conjugate Gradient method, incorporating the details of the detector and noise correlations. Simulations, as well as cross-correlations with Wilkinson Microwave Anisotropy Probe sky maps on large angular scales, reveal that our maps are unbiased at multipoles l > 300. This paper accompanies the public release of the 148 GHz southern stripe maps from 2008. The techniques described here will be applied to future maps and data releases.

  13. THE ATACAMA COSMOLOGY TELESCOPE: DATA CHARACTERIZATION AND MAPMAKING

    We present a description of the data reduction and mapmaking pipeline used for the 2008 observing season of the Atacama Cosmology Telescope (ACT). The data presented here at 148 GHz represent 12% of the 90 TB collected by ACT from 2007 to 2010. In 2008 we observed for 136 days, producing a total of 1423 hr of data (11 TB for the 148 GHz band only), with a daily average of 10.5 hr of observation. From these, 1085 hr were devoted to an 850 deg2 stripe (11.2 hr by 9.°1) centered on a declination of –52.°7, while 175 hr were devoted to a 280 deg2 stripe (4.5 hr by 4.°8) centered at the celestial equator. The remaining 163 hr correspond to calibration runs. We discuss sources of statistical and systematic noise, calibration, telescope pointing, and data selection. For the 148 GHz band, out of 1260 survey hours and 1024 detectors in the array, 816 hr and 593 effective detectors remain after data selection, yielding a 38% survey efficiency. The total sensitivity in 2008, determined from the noise level between 5 Hz and 20 Hz in the time-ordered data stream (TOD), is 32 μK√s in cosmic microwave background units. Atmospheric brightness fluctuations constitute the main contaminant in the data and dominate the detector noise covariance at low frequencies in the TOD. The maps were made by solving the least-squares problem using the Preconditioned Conjugate Gradient method, incorporating the details of the detector and noise correlations. Simulations, as well as cross-correlations with Wilkinson Microwave Anisotropy Probe sky maps on large angular scales, reveal that our maps are unbiased at multipoles l > 300. This paper accompanies the public release of the 148 GHz southern stripe maps from 2008. The techniques described here will be applied to future maps and data releases.

  14. Neutral Buoyancy Test - NB23 - Space Telescope

    1979-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. And construction methods had to be efficient due to limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. Included in the plans for the space station was a space telescope. This telescope would be attached to the space station and directed towards outerspace. Astronomers hoped that the space telescope would provide a look at space that is impossible to see from Earth because of Earth's atmosphere and other man made influences. In an effort to make replacement and repairs easier on astronauts the space telescope was designed to be modular. Practice makes perfect as demonstrated in this photo: an astronaut practices moving modular pieces of the space telescope in the Neutral

  15. The Student Telescope Network (STN) experiment

    Hannahoe, Ryan M.; Stencel, Robert E.; Bisque, Steve; Rice, Mike

    2003-02-01

    Several factors make observational astronomy difficult for pre-college students and teachers. (1) not many schools have teachers trained to use and maintain astronomy equipment; (2) school usually happens during the day and observing normally is a night-time activity; (3) the scourge of light pollution has hidden the stars from many students living in or near cities; (4) there is a general lack of access to expertise when needed. In addition, physically disabled students cannot climb ladders, to access the telescope eyepiece. Internet access to computer-controlled telescopes equipped with digital cameras can solve many of these difficulties. This enables students and their teachers to access well-maintained, robust Internet-controllable telescopes in dark-site locations and to consult more readily with experts. We present the results of technical solutions to Internet-control of telescopes, by Software Bisque, the New Mexico Skies Guest Observatory and the Youth Activities Committee of the Astronomical League in collaboration with Denver University Astronomy. We jointly submitted a funding proposal to the Institute for Connecting Science Research to the Classroom, and conducted a pilot program allowing high school students to access a CCD-equipped, accurately-pointing and tracking telescope, controllable over the Web, with a user-friendly skymap browser tool. With suitably placed telescopes worldwide, observing from the classroom in daylight will become feasible, as we have demonstrated with Australian and Eurasian student users of the New Mexico Skies Internet telescope. We report here on a three-month pilot project exploring this solution, conducted Feb-May 2002. User interest proved phenomenal, while user statistics proved diverse and there were distinct lessons learned about how to enhance student participation in the research process. We thank the Institute for Connecting Science Research to the Classroom for a grant to the University of Denver in partial

  16. Future perspectives for ground-based telescopes

    Full text: Technological developments now make it possible to observe planets orbiting other stars, peer deeper than ever into the universe, use particles and gravitational waves to study celestial sources, and to carry out in situ exploration of solar system objects. This promises tremendous progress towards answering key astronomical questions such as the nature of dark matter and dark energy; physics under extreme conditions including black holes, supernovae and gamma-ray bursts; the formation and evolution of galaxies from first light to the present, and the formation of stars and planets including the origin of our own solar system and the beginning of life. These are amongst the most fundamental scientific questions and are of enormous interest to the general public. A wide range of general purpose and dedicated observatories, on the ground and in space, is presently in operation or under development. Plans are being drawn up for a next generation of facilities, including extremely large telescopes for the optical and infrared, a radio telescope with very large collecting area, survey telescopes which would provide deep imaging of the sky every few nights, an advanced technology solar telescope, wide-field imagers in space, advanced planetary and solar missions, experiments to detect particles and gravitational waves, large x-ray telescopes, and space missions devoted to characterizing extra-solar planets. Construction of these facilities will require substantial investment by national funding agencies over the next decades. At their request, an integrated science vision was developed which identifies the most promising techniques and facilities needed to make substantial progress, followed by a road map for the development of the required infrastructure. The talk will discuss future ground-based facilities and highlight the role of ESO. (author)

  17. Hubble Space Telescope, Wide Field Planetary Camera

    1981-01-01

    This illustration is a diagram of the Hubble Space Telescope's (HST's), Wide Field Planetary Camera (WF/PC), one of the five Scientific Instruments. The WF/PC uses a four-sided pyramid mirror to split a light image into quarters. It then focuses each quadrant onto one of two sets of four sensors. The sensors are charge-coupled detectors and function as the electronic equivalent of extremely sensitive photographic plates. The WF/PC operates in two modes. The Wide-Field mode that will view 7.2-arcmin sections of the sky, and the Planetary mode that will look at narrower fields of view, such as planets or areas within other galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Cornecticut, developed the optical system and guidance sensors.

  18. The Spacewatch 1.8-meter Telescope

    Perry, M. L.; McMillan, R. S.; Barr, L. D.; Bressi, T. H.; Gehrels, T.

    1996-09-01

    The largest telescope in the world dedicated to the search for Earth-approaching asteroids and other previously unknown members of the solar system will soon be operational. Its 1.8-m aperture, large and sensitive CCD, and dedication to surveying will make it possible to find as many as 80,000 new asteroids per year. The mechanical design by Barr is optimized by finite-element analysis to provide high resonant frequencies. The mount is an altitude-azimuth type for compatibility with the mirror support cell contributed by the Multi-Mirror Telescope Observatory. Both axes are driven by DC servo motors directly coupled to friction rollers. The CCD instrument stage will also be rotated under computer control. The telescope was fabricated in the University Research Instrumentation Center (URIC). Construction of the building began on Kitt Peak on July 1, 1996. The optical configuration is f/2.7 folded prime focus with a flat secondary that locates the focal plane in the center of the optical truss near the altitude axis. This shortened the telescope enough to make the dome building affordable, and the flat secondary preserves the fast f/number of the primary mirror. The coma corrector designed by R. A. Buchroeder is a modified Klee design of 5 spherical lens elements plus a filter transmitting longward of the B bandpass. The filter greatly simplifies lens design and reduces sky background while not significantly reducing the brightness of asteroids. The distortion-free, flat, unvignetted field of view is 0.8 deg in diameter and the image scale is 1.0 arcsec/24 micron pixel. Construction of the Spacewatch Telescope has been funded by grants from the DoD Clementine Program, NASA, the University of Arizona Foundation, and other private and corporate donors.

  19. A Medium Sized Schwarzschild-Couder Cherenkov Telescope Mechanical Design Proposed for the Cherenkov Telescope Array

    Byrum, K; Benbow, W; Cameron, R; Criswell, S; Errando, M; Guarino, V; Kaaret, P; Kieda, D; Mukherjee, R; Naumann, D; Nieto, D; Northrop, R; Okumura, A; Roache, E; Rousselle, J; Schlenstedt, S; Sternberger, R; Vassiliev, V; Wakely, S; Zhao, H

    2015-01-01

    The Cherenkov Telescope Array (CTA) is an international next-generation ground-based gamma-ray observatory. CTA will be implemented as southern and northern hemisphere arrays of tens of small, medium and large-sized imaging Cherenkov telescopes with the goal of improving the sensitivity over the current-generation experiments by an order of magnitude. CTA will provide energy coverage from ~20 GeV to more than 300 TeV. The Schwarzschild-Couder (SC) medium size (9.5m) telescopes will feature a novel aplanatic two-mirror optical design capable of accommodating a wide field-of-view with significantly improved angular resolution as compared to the traditional Davies-Cotton optical design. A full-scale prototype SC medium size telescope structure has been designed and will be constructed at the Fred Lawrence Whipple Observatory in southern Arizona during the fall of 2015. concentrate on the novel features of the design.

  20. Looking Back in Time: Building the James Webb Space Telescope (JWST) Optical Telescope Element

    Feinberg, Lee

    2016-01-01

    When it launches in 2018, the James Webb Space Telescope (JWST) will look back in time at the earliest stars and galaxies forming in the universe. This talk will look back in time at the development of the JWST telescope. This will include a discussion of the design, technology development, mirror development, wave front sensing and control algorithms, lightweight cryogenic deployable structure, pathfinder telescope, and integration and test program evolution and status. The talk will provide the engineering answers on why the mirrors are made of Beryllium, why there are 18 segments, where and how the mirrors were made, how the mirrors get aligned using the main science camera, and how the telescope is being tested. It will also look back in time at the many dedicated people all over the country who helped build it.

  1. Status of the Medium-Sized Telescope for the Cherenkov Telescope Array

    ,

    2015-01-01

    The Cherenkov Telescope Array (CTA), is an international project for the next generation ground- based observatory for gamma-ray astronomy in the energy range from 20 GeV to 300 TeV. The sensitivity in the core energy range will be dominated by up to 40 Medium-Sized Telescopes (MSTs). The MSTs, of Davies-Cotton type with a 12 m diameter reflector are currently in the prototype phase. A full-size mechanical telescope structure has been assembled in Berlin. The telescope is partially equipped with different mirror prototypes, which are currently being tested and evaluated for performances characteristics. A report concentrating on the details of the tele- scope structure, the drive assemblies and the optics of the MST prototype will be given.

  2. Obstructed Telescopes vs Unobstructed Telescopes for Wide Field Survey - A Quantitative Analysis

    Singaravelu, Balasubramanian

    2014-01-01

    Telescopes with unobstructed pupil are known to deliver clean point spread function (PSF) to their focal plane, in contrast to traditional telescopes with obstructed pupil. Recent progress in the manufacturing aspheric surfaces and mounting accuracy favors unobstructed telescopes over obstructed telescopes for science cases that demand stable and clean PSF over the entire field-of-view. In this paper we compare the image quality of an unobstructed Three-Mirror-Anastigmat (TMA) design with that of an obstructed TMA. Both the designs have the same primary mirror, effective focal length, field-of-view and detector characteristics. We demonstrate using simulated images of faint elliptical galaxies imaged through the two designs, that both the designs can measure morphological parameters with same precision, if the PSF is reconstructed within 12 arc-minutes of the source. We also demonstrate that, the unobstructed design delivers desirable precision even if the PSF is reconstructed 50 arc-minutes away from the sou...

  3. THULE: A detailed description

    This report describes the THULE scheme of lattice physics calculation which has been developed in FORTRAN for the IBM 7090. This scheme predicts the neutron flux over energy and space, for many groups and regions, together with reactivity and reaction rate edits for both a single lattice cell and a reactor core. This report describes in detail the input requirements for the THULE programme which forms the main part of the scheme. Brief descriptions of the 7090 programmes TED 6 and NOAH are included as appendices. TED 6 will produce the THULE edits from a WDSN output tape and NOAH is a version of the METHUSELAH programme which contains many of the THULE edits and will also produce input cards for THULE. (author)

  4. Task Description Language

    Simmons, Reid; Apfelbaum, David

    2005-01-01

    Task Description Language (TDL) is an extension of the C++ programming language that enables programmers to quickly and easily write complex, concurrent computer programs for controlling real-time autonomous systems, including robots and spacecraft. TDL is based on earlier work (circa 1984 through 1989) on the Task Control Architecture (TCA). TDL provides syntactic support for hierarchical task-level control functions, including task decomposition, synchronization, execution monitoring, and exception handling. A Java-language-based compiler transforms TDL programs into pure C++ code that includes calls to a platform-independent task-control-management (TCM) library. TDL has been used to control and coordinate multiple heterogeneous robots in projects sponsored by NASA and the Defense Advanced Research Projects Agency (DARPA). It has also been used in Brazil to control an autonomous airship and in Canada to control a robotic manipulator.

  5. Mechanical design of SST-GATE, a dual-mirror telescope for the Cherenkov Telescope Array

    Dournaux, Jean-Laurent; Huet, Jean-Michel; Amans, Jean-Philippe; Dumas, Delphine; Laporte, Philippe; Sol, Hélène; Blake, Simon

    2014-07-01

    The Cherenkov Telescope Array (CTA) project aims to create the next generation Very High Energy (VHE) gamma-ray telescope array. It will be devoted to the observation of gamma rays over a wide band of energy, from a few tens of GeV to more than 100 TeV. Two sites are foreseen to view the whole sky where about 100 telescopes, composed of three different classes, related to the specific energy region to be investigated, will be installed. Among these, the Small Size class of Telescopes, SSTs, are devoted to the highest energy region, to beyond 100 TeV. Due to the large number of SSTs, their unit cost is an important parameter. At the Observatoire de Paris, we have designed a prototype of a Small Size Telescope named SST-GATE, based on the dual-mirror Schwarzschild-Couder optical formula, which has never before been implemented in the design of a telescope. Over the last two years, we developed a mechanical design for SST-GATE from the optical and preliminary mechanical designs made by the University of Durham. The integration of this telescope is currently in progress. Since the early stages of mechanical design of SST-GATE, finite element method has been used employing shape and topology optimization techniques to help design several elements of the telescope. This allowed optimization of the mechanical stiffness/mass ratio, leading to a lightweight and less expensive mechanical structure. These techniques and the resulting mechanical design are detailed in this paper. We will also describe the finite element analyses carried out to calculate the mechanical deformations and the stresses in the structure under observing and survival conditions.

  6. India’s Participation in the Thirty-Meter Telescope Project

    B. Eswar Reddy

    2013-06-01

    In 2010, the Department of Science and Technology (DST), Govt. of India, approved astronomers’ proposal of India joining the international consortium of the USA, Japan, Canada and China to build and operate the next generation mega ground based optical and infrared telescope known as the Thirty-Meter Telescope (TMT) after its aperture size of 30-meter diameter. Since then, India is engaged in many aspects of the TMT project, both at technical and policy levels. In this article, I confine to the description of India’s efforts leading up to the decision to join the consortium, and the progress made since then with respect to India’s technical contributions to the project.

  7. Correlated Oscillations Due to Similar Multipath Effects Seen in Two Widely Separated Radio Telescopes

    Diep, P. N.; Phuong, N. T.; Darriulat, P.; Nhung, P. T.; Anh, P. T.; Dong, P. N.; Hoai, D. T.; Thao, N. T.

    2014-07-01

    A multipath mechanism similar to that used in Australia sixty years ago by the Sea-cliff Interferometer is shown to generate correlations between the periods of oscillations observed by two distant radio telescopes pointed to the Sun. The oscillations are the result of interferences between the direct wave detected in the main antenna lobe and its reflection on ground detected in a side lobe. A model is made of such oscillations in the case of two observatories located at equal longitudes and opposite tropical latitudes, respectively in Ha Noi (Viet Nam) and Learmonth (Australia), where similar radio telescopes are operated at 1.4 GHz. Simple specular reflection from ground is found to give a good description of the observed oscillations and to explain correlations that had been previously observed and for which no satisfactory interpretation, instrumental or other, had been found.

  8. Status of the eROSITA Telescope testing and calibrating the x-ray mirror assemblies

    Burwitz, Vadim; Predehl, Peter; Bräuninger, Heinrich; Burkert, Wolfgang; Dennerl, Konrad; Eder, Josef; Friedrich, Peter; Fürmetz, Maria; Grisoni, Gabriele; Hartner, Gisela; Marioni, Fabio; Menz, Benedikt; Pfeffermann, Elmar; Valsecchi, Giuseppe

    2013-09-01

    The eROSITA X-ray observatory that will be launched on board the Russian Spectrum-RG mission comprises seven X-ray telescopes, each with its own mirror assembly (mirror module + X-ray baffle), electron deflector, filter wheel, and CCD camera with its control electronics. The completed flight mirror modules are undergoing many thorough X-ray tests at the PANTHER X-ray test facility after delivery, after being mated with the X-ray baffle, and again after both the vibration and thermal-vacuum tests. A description of the work done with mirror modules/assemblies and the test results obtained will be reported here. We report also on the environmental tests that have been performed on the eROSITA telescope qualification model.

  9. Primary Mirror Figure Maintenance of the Hobby-Eberly Telescope using the Segment Alignment Maintenance System

    Rakoczy, John; Hall, Drew; Howard, Ricky; Ly, William; Weir, John; Montgomery, Edward; Brantley, Lott W. (Technical Monitor)

    2002-01-01

    The Segment Alignment Maintenance System (SAMs) was installed on McDonald Observatory's Hobby-Eberly Telescope (HET) in August 2001. The SAMs became fully operational in October 2001. The SAMs uses a system of 480 inductive edge sensors to correct misalignments of the HET's 91 primary mirror segments when the segments are perturbed from their aligned reference positions. A special observer estimated and corrects for the global radius of curvature (GroC) mode, a mode unobservable by the edge sensors. The SAMs edge sensor system and (GroC) estimator are able to maintain HET's primary figure for much longer durations than previously had been observed. Telescope image quality has improved, and the amount of overhead time required from primary mirror alignment has been reduced. This paper gives a functional description of the SAMs control system and presents performance verification data. This paper also describes how the SAMs has improved the operational efficiency of the HET.

  10. YUCCA MOUNTAIN SITE DESCRIPTION

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  11. YUCCA MOUNTAIN SITE DESCRIPTION

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel

  12. Olkiluoto site description 2004

    This Olkiluoto Site Description 2004 is a description of the Olkiluoto site, in which the various disciplines have been integrated to produce a coherent picture, and is based on the data available prior to the start of the underground excavation of the ONKALO facility. This report is the first version of such a Site Report and supplements the site syntheses that have already been published. Further Site Reports will be produced on a regular basis and it is planned that the Site Report should form the geoscientific basis of the Safety Case in a future licence application. The report updates the Baseline report published in 2003 and is designed to produce an integrated site model, by focusing on interdisciplinary interactions, and also by including new data obtained during 2003 and 2004. The report has been produced by the OMTF (Olkiluoto Modelling Task Force), which covers the areas of geology, rock mechanics, hydrogeology and hydrogeochemistry. In addition to discussing the input from these four disciplines, the Site Report also includes a description of the surface conditions. Formally, the surface conditions are not within the remit of the OMTF, which is concentrating on modelling the bedrock around the ONKALO and the future repository. The influence of the surface conditions to the overall system and to the conditions at depth is recognised, however, and thus a summary of climate, ecosystems and overburden properties is also included in this report. Chapter 1 sets out the methodology to be used in the modelling, describes the various discipline-specific models which are developed and the modelled areas which are used, and also describes two important processes - the prediction/outcome studies and the uncertainty and confidence assessment. The difference between the estimate (the prediction) and the result (the outcome) indicates the level of knowledge and the prevailing uncertainties in the models. Chapter 2 presents the applied investigation data, which are

  13. NASA 3D Models: James Webb Space Telescope

    National Aeronautics and Space Administration — The James Webb Space Telescope (JWST) will be a large infrared telescope with a 6.5-meter primary mirror. The project is working to a 2018 launch date. The JWST...

  14. Pointing Calibration for the Cherenkov Telescope Array Medium Size Telescope Prototype

    Oakes, Louise; Baehr, Juergen; Gruenewald, Sandra; Raeck, Tobias; Schlenstedt, Stefan; Schubert, Anja; Schwanke, Ullrich

    2013-01-01

    Pointing calibration is an offline correction applied in order to obtain the true pointing direction of a telescope. The Cherenkov Telescope Array (CTA) aims to have the precision to determine the position of point-like as well as slightly extended sources, with the goal of systematic errors less than 7 arc seconds in space angle. This poster describes the pointing calibration concept being developed for the CTA Medium Size Telescope (MST) prototype at Berlin-Adlershof, showing test results and preliminary measurements. The MST pointing calibration method uses two CCD cameras, mounted on the telescope dish, to determine the true pointing of the telescope. The "Lid CCD" is aligned to the optical axis of the telescope, calibrated with LEDs on the dummy gamma-camera lid; the "Sky CCD" is pre-aligned to the Lid CCD and the transformation between the Sky and Lid CCD camera fields of view is precisely modelled with images from special pointing runs which are also used to determine the pointing model. During source ...

  15. Construction Milestone Announced on Green Bank Telescope

    2000-04-01

    The National Radio Astronomy Observatory announces completion of a major construction milestone on the world's largest fully steerable radio telescope - the National Science Foundation's Green Bank Telescope (GBT). The last of 2,004 aluminum surface panels was recently installed on the GBT's two-acre (100 m x 110 m) collecting dish. The telescope is located at NRAO's Green Bank site, in rural Pocahontas County, West Virginia. The GBT will be used to study everything from the formation of galaxies in the early universe, to the chemical make-up of the dust and gas inside galaxies and in the voids that separate them, to the birth processes of stars. In conjunction with other instruments, it will help make highly accurate radar maps of some familiar objects in our own solar system. The GBT is an engineering marvel. At 485 feet tall, it is comparable in height to the Washington Monument. It weighs 16 million pounds, yet by swiveling the dish in both azimuth and elevation, it can be pointed to any point in the sky with exquisite accuracy. Additionally, the telescope's two-acre collecting dish has many novel features. Most radio telescopes in use today use receivers suspended above the dish by four struts. These struts block some of the surface of the dish, scattering some of the incoming radio waves from celestial objects under study. The GBT's offset feedarm has no struts to block incoming radio waves. The GBT also boasts an active surface. The surface of the dish is composed of 2,004 panels. On the underside of the dish, actuators are located at each corner (i.e., intersection of four panels). These actuators are motors that move the surface panels up and down, keeping the (paraboloid) shape of the dish precisely adjusted, no matter what the tilt of the telescope. The combination of its unblocked aperture and active surface promise that the GBT will display extremely high sensitivity to faint radio signals. The GBT itself is not the only precious national resource in

  16. Optimal Survey Strategies and Predicted Planet Yields for the Korean Microlensing Telescope Network

    Henderson, Calen B; Han, Cheongho; Skowron, Jan; Penny, Matthew T; Nataf, David; Gould, Andrew P

    2014-01-01

    The Korean Microlensing Telescope Network (KMTNet) will consist of three 1.6m telescopes each with a 4 deg^{2} field of view (FoV) and will be dedicated to monitoring the Galactic Bulge to detect exoplanets via gravitational microlensing. KMTNet's combination of aperture size, FoV, cadence, and longitudinal coverage will provide a unique opportunity to probe exoplanet demographics in an unbiased way. Here we present simulations that optimize the observing strategy for, and predict the planetary yields of, KMTNet. We find preferences for four target fields located in the central Bulge and an exposure time of t_{exp} = 120s, leading to the detection of ~2,200 microlensing events per year. We estimate the planet detection rates for planets with mass and separation across the ranges 0.1 <= M_{p}/M_{Earth} <= 1000 and 0.4 <= a/AU <= 16, respectively. Normalizing these rates to the cool-planet mass function of Cassan (2012), we predict KMTNet will be approximately uniformly sensitive to planets with mas...

  17. Primary Beam and Dish Surface Characterization at the Allen Telescope Array by Radio Holography

    Atkinson, Shannon; Backus, P R; Barott, William; Bauermeister, Amber; Blitz, Leo; Bock, D C -J; Bower, Geoffrey C; Bradford, Tucker; Cheng, Calvin; Croft, Steve; Dexter, Matt; Dreher, John; Engargiola, Greg; Fields, Ed; Heiles, Carl; Helfer, Tamara; Jordan, Jane; Jorgensen, Susan; Kilsdonk, Tom; Gutierrez-Kraybill, Colby; Keating, Garrett; Law, Casey; Lugten, John; MacMahon, D H E; McMahon, Peter; Milgrome, Oren; Siemion, Andrew; Smolek, Ken; Thornton, Douglas; Pierson, Tom; Randall, Karen; Ross, John; Shostak, Seth; Tarter, J C; Urry, Lynn; Werthimer, Dan; Williams, Peter K G; Whysong, David; Harp, G R; Ackermann, R F; Nadler, Z J; Blair, Samantha K; Davis, M M; Wright, M C H; Forster, J R; DeBoer, D R; Welch, W J

    2012-01-01

    The Allen Telescope Array (ATA) is a cm-wave interferometer in California, comprising 42 antenna elements with 6-m diameter dishes. We characterize the antenna optical accuracy using two-antenna interferometry and radio holography. The distortion of each telescope relative to the average is small, with RMS differences of 1 percent of beam peak value. Holography provides images of dish illumination pattern, allowing characterization of as-built mirror surfaces. The ATA dishes can experience mm-scale distortions across -2 meter lengths due to mounting stresses or solar radiation. Experimental RMS errors are 0.7 mm at night and 3 mm under worst case solar illumination. For frequencies 4, 10, and 15 GHz, the nighttime values indicate sensitivity losses of 1, 10 and 20 percent, respectively. The ATA.s exceptional wide-bandwidth permits observations over a continuous range 0.5 to 11.2 GHz, and future retrofits may increase this range to 15 GHz. Beam patterns show a slowly varying focus frequency dependence. We prob...

  18. Telescope Aiming Point Tracking Method for Bioptic Driving Surveillance

    Fu, Xianping; Luo, Gang; Peli, Eli

    2010-01-01

    A bioptic telescope is a visual aid used by people with impaired vision when driving in many US states, though bioptic driving remains controversial. Objective data on how and when bioptic drivers use the telescope and what they look at with it are crucial to understanding the bioptic telescope's effect on driving. A video-based technique to track the telescope's aiming point is presented in this paper. With three infrared retro-reflective markers pasted on the bioptic spectacles' frame, its ...

  19. The Formation of Condensation on Cherenkov Telescope Mirrors

    Chadwick, P M; Dyrda, M; Förster, A; Michalowski, J; Niemiec, J; Schultz, C; Stodulski, M

    2013-01-01

    The mirrors of imaging atmospheric Cherenkov telescopes are different from those of conventional astronomical telescopes in several ways, not least in that they are exposed to the elements. One of the issues which may arise is condensation forming on the mirrors during observing under certain atmospheric conditions, which has important consequences for the operation of the telescopes. This contribution discusses why telescope mirrors suffer condensation and describes the atmospheric conditions and mirror designs which are likely to be problematic.

  20. Formal description technique SDL for manufacturing systems specification and description

    Sousa, Rui M.; Putnik, Goran D.

    1999-01-01

    This paper addresses the formal specification and description of manufacturing systems. It is considered the use of SDL (Specification and Description Language), a standard FDT (Formal Description Technique), to model the behaviour, data and structure aspects of a manufacturing system. SDL was originally developed for telecommunication systems (protocol specification and data processing). The adequacy of FDTs, namely SDL, for the manufacturing systems domain is investigated by developing the ...